* [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: peter.maydell, sstabellini, groug, Stefano Stabellini, stefanha,
pbonzini, anthony.perard, xen-devel, rth
CONFIG_XEN_BACKEND is currently set when the host supports Xen,
regardless of the chosen targets. As a consequence, Xen backends can be
enabled even on targets that don't support Xen.
Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
support Xen.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: groug@kaod.org
CC: groug@kaod.org
CC: pbonzini@redhat.com
CC: peter.maydell@linaro.org
CC: rth@twiddle.net
CC: stefanha@redhat.com
---
configure | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/configure b/configure
index 6c21975..6d8f752 100755
--- a/configure
+++ b/configure
@@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
fi
if test "$xen" = "yes" ; then
- echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
if test "$xen_pv_domain_build" = "yes" ; then
echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
@@ -6028,6 +6027,7 @@ case "$target_name" in
i386|x86_64)
if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
echo "CONFIG_XEN=y" >> $config_target_mak
+ echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
if test "$xen_pci_passthrough" = yes; then
echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
fi
--
1.9.1
_______________________________________________
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Xen-devel@lists.xen.org
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^ permalink raw reply related [flat|nested] 72+ messages in thread* [Qemu-devel] [PATCH v2 2/9] xen: import ring.h from xen
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:55 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross
Do not use the ring.h header installed on the system. Instead, import
the header into the QEMU codebase. This avoids problems when QEMU is
built against a Xen version too old to provide all the ring macros.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
---
NB: The new macros have not been committed to Xen yet. Do not apply this
patch until they do.
---
---
hw/block/xen_blkif.h | 2 +-
hw/usb/xen-usb.c | 2 +-
include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 457 insertions(+), 2 deletions(-)
create mode 100644 include/hw/xen/io/ring.h
diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
index 3300b6f..3e6e1ea 100644
--- a/hw/block/xen_blkif.h
+++ b/hw/block/xen_blkif.h
@@ -1,7 +1,7 @@
#ifndef XEN_BLKIF_H
#define XEN_BLKIF_H
-#include <xen/io/ring.h>
+#include "hw/xen/io/ring.h"
#include <xen/io/blkif.h>
#include <xen/io/protocols.h>
diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
index 8e676e6..370b3d9 100644
--- a/hw/usb/xen-usb.c
+++ b/hw/usb/xen-usb.c
@@ -33,7 +33,7 @@
#include "qapi/qmp/qint.h"
#include "qapi/qmp/qstring.h"
-#include <xen/io/ring.h>
+#include "hw/xen/io/ring.h"
#include <xen/io/usbif.h>
/*
diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
new file mode 100644
index 0000000..cf01fc3
--- /dev/null
+++ b/include/hw/xen/io/ring.h
@@ -0,0 +1,455 @@
+/******************************************************************************
+ * ring.h
+ *
+ * Shared producer-consumer ring macros.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Tim Deegan and Andrew Warfield November 2004.
+ */
+
+#ifndef __XEN_PUBLIC_IO_RING_H__
+#define __XEN_PUBLIC_IO_RING_H__
+
+#if __XEN_INTERFACE_VERSION__ < 0x00030208
+#define xen_mb() mb()
+#define xen_rmb() rmb()
+#define xen_wmb() wmb()
+#endif
+
+typedef unsigned int RING_IDX;
+
+/* Round a 32-bit unsigned constant down to the nearest power of two. */
+#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
+#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
+#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
+#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
+#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
+
+/*
+ * Calculate size of a shared ring, given the total available space for the
+ * ring and indexes (_sz), and the name tag of the request/response structure.
+ * A ring contains as many entries as will fit, rounded down to the nearest
+ * power of two (so we can mask with (size-1) to loop around).
+ */
+#define __CONST_RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
+ sizeof(((struct _s##_sring *)0)->ring[0])))
+/*
+ * The same for passing in an actual pointer instead of a name tag.
+ */
+#define __RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
+
+/*
+ * Macros to make the correct C datatypes for a new kind of ring.
+ *
+ * To make a new ring datatype, you need to have two message structures,
+ * let's say request_t, and response_t already defined.
+ *
+ * In a header where you want the ring datatype declared, you then do:
+ *
+ * DEFINE_RING_TYPES(mytag, request_t, response_t);
+ *
+ * These expand out to give you a set of types, as you can see below.
+ * The most important of these are:
+ *
+ * mytag_sring_t - The shared ring.
+ * mytag_front_ring_t - The 'front' half of the ring.
+ * mytag_back_ring_t - The 'back' half of the ring.
+ *
+ * To initialize a ring in your code you need to know the location and size
+ * of the shared memory area (PAGE_SIZE, for instance). To initialise
+ * the front half:
+ *
+ * mytag_front_ring_t front_ring;
+ * SHARED_RING_INIT((mytag_sring_t *)shared_page);
+ * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ *
+ * Initializing the back follows similarly (note that only the front
+ * initializes the shared ring):
+ *
+ * mytag_back_ring_t back_ring;
+ * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ */
+
+#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
+ \
+/* Shared ring entry */ \
+union __name##_sring_entry { \
+ __req_t req; \
+ __rsp_t rsp; \
+}; \
+ \
+/* Shared ring page */ \
+struct __name##_sring { \
+ RING_IDX req_prod, req_event; \
+ RING_IDX rsp_prod, rsp_event; \
+ union { \
+ struct { \
+ uint8_t smartpoll_active; \
+ } netif; \
+ struct { \
+ uint8_t msg; \
+ } tapif_user; \
+ uint8_t pvt_pad[4]; \
+ } pvt; \
+ uint8_t __pad[44]; \
+ union __name##_sring_entry ring[1]; /* variable-length */ \
+}; \
+ \
+/* "Front" end's private variables */ \
+struct __name##_front_ring { \
+ RING_IDX req_prod_pvt; \
+ RING_IDX rsp_cons; \
+ unsigned int nr_ents; \
+ struct __name##_sring *sring; \
+}; \
+ \
+/* "Back" end's private variables */ \
+struct __name##_back_ring { \
+ RING_IDX rsp_prod_pvt; \
+ RING_IDX req_cons; \
+ unsigned int nr_ents; \
+ struct __name##_sring *sring; \
+}; \
+ \
+/* Syntactic sugar */ \
+typedef struct __name##_sring __name##_sring_t; \
+typedef struct __name##_front_ring __name##_front_ring_t; \
+typedef struct __name##_back_ring __name##_back_ring_t
+
+/*
+ * Macros for manipulating rings.
+ *
+ * FRONT_RING_whatever works on the "front end" of a ring: here
+ * requests are pushed on to the ring and responses taken off it.
+ *
+ * BACK_RING_whatever works on the "back end" of a ring: here
+ * requests are taken off the ring and responses put on.
+ *
+ * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
+ * This is OK in 1-for-1 request-response situations where the
+ * requestor (front end) never has more than RING_SIZE()-1
+ * outstanding requests.
+ */
+
+/* Initialising empty rings */
+#define SHARED_RING_INIT(_s) do { \
+ (_s)->req_prod = (_s)->rsp_prod = 0; \
+ (_s)->req_event = (_s)->rsp_event = 1; \
+ (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
+ (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
+} while(0)
+
+#define FRONT_RING_INIT(_r, _s, __size) do { \
+ (_r)->req_prod_pvt = 0; \
+ (_r)->rsp_cons = 0; \
+ (_r)->nr_ents = __RING_SIZE(_s, __size); \
+ (_r)->sring = (_s); \
+} while (0)
+
+#define BACK_RING_INIT(_r, _s, __size) do { \
+ (_r)->rsp_prod_pvt = 0; \
+ (_r)->req_cons = 0; \
+ (_r)->nr_ents = __RING_SIZE(_s, __size); \
+ (_r)->sring = (_s); \
+} while (0)
+
+/* How big is this ring? */
+#define RING_SIZE(_r) \
+ ((_r)->nr_ents)
+
+/* Number of free requests (for use on front side only). */
+#define RING_FREE_REQUESTS(_r) \
+ (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
+
+/* Test if there is an empty slot available on the front ring.
+ * (This is only meaningful from the front. )
+ */
+#define RING_FULL(_r) \
+ (RING_FREE_REQUESTS(_r) == 0)
+
+/* Test if there are outstanding messages to be processed on a ring. */
+#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+ ((_r)->sring->rsp_prod - (_r)->rsp_cons)
+
+#ifdef __GNUC__
+#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
+ unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
+ unsigned int rsp = RING_SIZE(_r) - \
+ ((_r)->req_cons - (_r)->rsp_prod_pvt); \
+ req < rsp ? req : rsp; \
+})
+#else
+/* Same as above, but without the nice GCC ({ ... }) syntax. */
+#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
+ ((((_r)->sring->req_prod - (_r)->req_cons) < \
+ (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
+ ((_r)->sring->req_prod - (_r)->req_cons) : \
+ (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
+#endif
+
+/* Direct access to individual ring elements, by index. */
+#define RING_GET_REQUEST(_r, _idx) \
+ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
+
+/*
+ * Get a local copy of a request.
+ *
+ * Use this in preference to RING_GET_REQUEST() so all processing is
+ * done on a local copy that cannot be modified by the other end.
+ *
+ * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
+ * to be ineffective where _req is a struct which consists of only bitfields.
+ */
+#define RING_COPY_REQUEST(_r, _idx, _req) do { \
+ /* Use volatile to force the copy into _req. */ \
+ *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
+} while (0)
+
+#define RING_GET_RESPONSE(_r, _idx) \
+ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
+
+/* Loop termination condition: Would the specified index overflow the ring? */
+#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
+ (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
+
+/* Ill-behaved frontend determination: Can there be this many requests? */
+#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
+ (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
+
+#define RING_PUSH_REQUESTS(_r) do { \
+ xen_wmb(); /* back sees requests /before/ updated producer index */ \
+ (_r)->sring->req_prod = (_r)->req_prod_pvt; \
+} while (0)
+
+#define RING_PUSH_RESPONSES(_r) do { \
+ xen_wmb(); /* front sees resps /before/ updated producer index */ \
+ (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
+} while (0)
+
+/*
+ * Notification hold-off (req_event and rsp_event):
+ *
+ * When queueing requests or responses on a shared ring, it may not always be
+ * necessary to notify the remote end. For example, if requests are in flight
+ * in a backend, the front may be able to queue further requests without
+ * notifying the back (if the back checks for new requests when it queues
+ * responses).
+ *
+ * When enqueuing requests or responses:
+ *
+ * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
+ * is a boolean return value. True indicates that the receiver requires an
+ * asynchronous notification.
+ *
+ * After dequeuing requests or responses (before sleeping the connection):
+ *
+ * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
+ * The second argument is a boolean return value. True indicates that there
+ * are pending messages on the ring (i.e., the connection should not be put
+ * to sleep).
+ *
+ * These macros will set the req_event/rsp_event field to trigger a
+ * notification on the very next message that is enqueued. If you want to
+ * create batches of work (i.e., only receive a notification after several
+ * messages have been enqueued) then you will need to create a customised
+ * version of the FINAL_CHECK macro in your own code, which sets the event
+ * field appropriately.
+ */
+
+#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
+ RING_IDX __old = (_r)->sring->req_prod; \
+ RING_IDX __new = (_r)->req_prod_pvt; \
+ xen_wmb(); /* back sees requests /before/ updated producer index */ \
+ (_r)->sring->req_prod = __new; \
+ xen_mb(); /* back sees new requests /before/ we check req_event */ \
+ (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
+ (RING_IDX)(__new - __old)); \
+} while (0)
+
+#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
+ RING_IDX __old = (_r)->sring->rsp_prod; \
+ RING_IDX __new = (_r)->rsp_prod_pvt; \
+ xen_wmb(); /* front sees resps /before/ updated producer index */ \
+ (_r)->sring->rsp_prod = __new; \
+ xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
+ (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
+ (RING_IDX)(__new - __old)); \
+} while (0)
+
+#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
+ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+ if (_work_to_do) break; \
+ (_r)->sring->req_event = (_r)->req_cons + 1; \
+ xen_mb(); \
+ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+} while (0)
+
+#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
+ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+ if (_work_to_do) break; \
+ (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
+ xen_mb(); \
+ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+} while (0)
+
+
+/*
+ * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
+ * functions to check if there is data on the ring, and to read and
+ * write to them.
+ *
+ * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
+ * does not define the indexes page. As different protocols can have
+ * extensions to the basic format, this macro allow them to define their
+ * own struct.
+ *
+ * XEN_FLEX_RING_SIZE
+ * Convenience macro to calculate the size of one of the two rings
+ * from the overall order.
+ *
+ * $NAME_mask
+ * Function to apply the size mask to an index, to reduce the index
+ * within the range [0-size].
+ *
+ * $NAME_read_packet
+ * Function to read data from the ring. The amount of data to read is
+ * specified by the "size" argument.
+ *
+ * $NAME_write_packet
+ * Function to write data to the ring. The amount of data to write is
+ * specified by the "size" argument.
+ *
+ * $NAME_get_ring_ptr
+ * Convenience function that returns a pointer to read/write to the
+ * ring at the right location.
+ *
+ * $NAME_data_intf
+ * Indexes page, shared between frontend and backend. It also
+ * contains the array of grant refs.
+ *
+ * $NAME_queued
+ * Function to calculate how many bytes are currently on the ring,
+ * ready to be read. It can also be used to calculate how much free
+ * space is currently on the ring (ring_size - $NAME_queued()).
+ */
+#define XEN_FLEX_RING_SIZE(order) \
+ (1UL << (order + PAGE_SHIFT - 1))
+
+#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
+struct name##_data_intf { \
+ RING_IDX in_cons, in_prod; \
+ \
+ uint8_t pad1[56]; \
+ \
+ RING_IDX out_cons, out_prod; \
+ \
+ uint8_t pad2[56]; \
+ \
+ RING_IDX ring_order; \
+ grant_ref_t ref[]; \
+}; \
+DEFINE_XEN_FLEX_RING(name);
+
+#define DEFINE_XEN_FLEX_RING(name) \
+static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
+{ \
+ return (idx & (ring_size - 1)); \
+} \
+ \
+static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
+{ \
+ return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
+} \
+ \
+static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
+ RING_IDX idx, \
+ RING_IDX ring_order) \
+{ \
+ return buf + name##_mask_order(idx, ring_order); \
+} \
+ \
+static inline void name##_read_packet(const unsigned char *buf, \
+ RING_IDX masked_prod, RING_IDX *masked_cons, \
+ RING_IDX ring_size, void *opaque, size_t size) { \
+ if (*masked_cons < masked_prod || \
+ size <= ring_size - *masked_cons) { \
+ memcpy(opaque, buf + *masked_cons, size); \
+ } else { \
+ memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
+ memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
+ size - (ring_size - *masked_cons)); \
+ } \
+ *masked_cons = name##_mask(*masked_cons + size, ring_size); \
+} \
+ \
+static inline void name##_write_packet(unsigned char *buf, \
+ RING_IDX *masked_prod, RING_IDX masked_cons, \
+ RING_IDX ring_size, const void *opaque, size_t size) { \
+ if (*masked_prod < masked_cons || \
+ size <= ring_size - *masked_prod) { \
+ memcpy(buf + *masked_prod, opaque, size); \
+ } else { \
+ memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
+ memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
+ size - (ring_size - *masked_prod)); \
+ } \
+ *masked_prod = name##_mask(*masked_prod + size, ring_size); \
+} \
+ \
+struct name##_data { \
+ unsigned char *in; /* half of the allocation */ \
+ unsigned char *out; /* half of the allocation */ \
+}; \
+ \
+ \
+static inline RING_IDX name##_queued(RING_IDX prod, \
+ RING_IDX cons, RING_IDX ring_size) \
+{ \
+ RING_IDX size; \
+ \
+ if (prod == cons) \
+ return 0; \
+ \
+ prod = name##_mask(prod, ring_size); \
+ cons = name##_mask(cons, ring_size); \
+ \
+ if (prod == cons) \
+ return ring_size; \
+ \
+ if (prod > cons) \
+ size = prod - cons; \
+ else \
+ size = ring_size - (cons - prod); \
+ return size; \
+};
+
+#endif /* __XEN_PUBLIC_IO_RING_H__ */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 2/9] xen: import ring.h from xen
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, anthony.perard,
xen-devel
Do not use the ring.h header installed on the system. Instead, import
the header into the QEMU codebase. This avoids problems when QEMU is
built against a Xen version too old to provide all the ring macros.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
---
NB: The new macros have not been committed to Xen yet. Do not apply this
patch until they do.
---
---
hw/block/xen_blkif.h | 2 +-
hw/usb/xen-usb.c | 2 +-
include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 457 insertions(+), 2 deletions(-)
create mode 100644 include/hw/xen/io/ring.h
diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
index 3300b6f..3e6e1ea 100644
--- a/hw/block/xen_blkif.h
+++ b/hw/block/xen_blkif.h
@@ -1,7 +1,7 @@
#ifndef XEN_BLKIF_H
#define XEN_BLKIF_H
-#include <xen/io/ring.h>
+#include "hw/xen/io/ring.h"
#include <xen/io/blkif.h>
#include <xen/io/protocols.h>
diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
index 8e676e6..370b3d9 100644
--- a/hw/usb/xen-usb.c
+++ b/hw/usb/xen-usb.c
@@ -33,7 +33,7 @@
#include "qapi/qmp/qint.h"
#include "qapi/qmp/qstring.h"
-#include <xen/io/ring.h>
+#include "hw/xen/io/ring.h"
#include <xen/io/usbif.h>
/*
diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
new file mode 100644
index 0000000..cf01fc3
--- /dev/null
+++ b/include/hw/xen/io/ring.h
@@ -0,0 +1,455 @@
+/******************************************************************************
+ * ring.h
+ *
+ * Shared producer-consumer ring macros.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Tim Deegan and Andrew Warfield November 2004.
+ */
+
+#ifndef __XEN_PUBLIC_IO_RING_H__
+#define __XEN_PUBLIC_IO_RING_H__
+
+#if __XEN_INTERFACE_VERSION__ < 0x00030208
+#define xen_mb() mb()
+#define xen_rmb() rmb()
+#define xen_wmb() wmb()
+#endif
+
+typedef unsigned int RING_IDX;
+
+/* Round a 32-bit unsigned constant down to the nearest power of two. */
+#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
+#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
+#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
+#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
+#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
+
+/*
+ * Calculate size of a shared ring, given the total available space for the
+ * ring and indexes (_sz), and the name tag of the request/response structure.
+ * A ring contains as many entries as will fit, rounded down to the nearest
+ * power of two (so we can mask with (size-1) to loop around).
+ */
+#define __CONST_RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
+ sizeof(((struct _s##_sring *)0)->ring[0])))
+/*
+ * The same for passing in an actual pointer instead of a name tag.
+ */
+#define __RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
+
+/*
+ * Macros to make the correct C datatypes for a new kind of ring.
+ *
+ * To make a new ring datatype, you need to have two message structures,
+ * let's say request_t, and response_t already defined.
+ *
+ * In a header where you want the ring datatype declared, you then do:
+ *
+ * DEFINE_RING_TYPES(mytag, request_t, response_t);
+ *
+ * These expand out to give you a set of types, as you can see below.
+ * The most important of these are:
+ *
+ * mytag_sring_t - The shared ring.
+ * mytag_front_ring_t - The 'front' half of the ring.
+ * mytag_back_ring_t - The 'back' half of the ring.
+ *
+ * To initialize a ring in your code you need to know the location and size
+ * of the shared memory area (PAGE_SIZE, for instance). To initialise
+ * the front half:
+ *
+ * mytag_front_ring_t front_ring;
+ * SHARED_RING_INIT((mytag_sring_t *)shared_page);
+ * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ *
+ * Initializing the back follows similarly (note that only the front
+ * initializes the shared ring):
+ *
+ * mytag_back_ring_t back_ring;
+ * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ */
+
+#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
+ \
+/* Shared ring entry */ \
+union __name##_sring_entry { \
+ __req_t req; \
+ __rsp_t rsp; \
+}; \
+ \
+/* Shared ring page */ \
+struct __name##_sring { \
+ RING_IDX req_prod, req_event; \
+ RING_IDX rsp_prod, rsp_event; \
+ union { \
+ struct { \
+ uint8_t smartpoll_active; \
+ } netif; \
+ struct { \
+ uint8_t msg; \
+ } tapif_user; \
+ uint8_t pvt_pad[4]; \
+ } pvt; \
+ uint8_t __pad[44]; \
+ union __name##_sring_entry ring[1]; /* variable-length */ \
+}; \
+ \
+/* "Front" end's private variables */ \
+struct __name##_front_ring { \
+ RING_IDX req_prod_pvt; \
+ RING_IDX rsp_cons; \
+ unsigned int nr_ents; \
+ struct __name##_sring *sring; \
+}; \
+ \
+/* "Back" end's private variables */ \
+struct __name##_back_ring { \
+ RING_IDX rsp_prod_pvt; \
+ RING_IDX req_cons; \
+ unsigned int nr_ents; \
+ struct __name##_sring *sring; \
+}; \
+ \
+/* Syntactic sugar */ \
+typedef struct __name##_sring __name##_sring_t; \
+typedef struct __name##_front_ring __name##_front_ring_t; \
+typedef struct __name##_back_ring __name##_back_ring_t
+
+/*
+ * Macros for manipulating rings.
+ *
+ * FRONT_RING_whatever works on the "front end" of a ring: here
+ * requests are pushed on to the ring and responses taken off it.
+ *
+ * BACK_RING_whatever works on the "back end" of a ring: here
+ * requests are taken off the ring and responses put on.
+ *
+ * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
+ * This is OK in 1-for-1 request-response situations where the
+ * requestor (front end) never has more than RING_SIZE()-1
+ * outstanding requests.
+ */
+
+/* Initialising empty rings */
+#define SHARED_RING_INIT(_s) do { \
+ (_s)->req_prod = (_s)->rsp_prod = 0; \
+ (_s)->req_event = (_s)->rsp_event = 1; \
+ (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
+ (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
+} while(0)
+
+#define FRONT_RING_INIT(_r, _s, __size) do { \
+ (_r)->req_prod_pvt = 0; \
+ (_r)->rsp_cons = 0; \
+ (_r)->nr_ents = __RING_SIZE(_s, __size); \
+ (_r)->sring = (_s); \
+} while (0)
+
+#define BACK_RING_INIT(_r, _s, __size) do { \
+ (_r)->rsp_prod_pvt = 0; \
+ (_r)->req_cons = 0; \
+ (_r)->nr_ents = __RING_SIZE(_s, __size); \
+ (_r)->sring = (_s); \
+} while (0)
+
+/* How big is this ring? */
+#define RING_SIZE(_r) \
+ ((_r)->nr_ents)
+
+/* Number of free requests (for use on front side only). */
+#define RING_FREE_REQUESTS(_r) \
+ (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
+
+/* Test if there is an empty slot available on the front ring.
+ * (This is only meaningful from the front. )
+ */
+#define RING_FULL(_r) \
+ (RING_FREE_REQUESTS(_r) == 0)
+
+/* Test if there are outstanding messages to be processed on a ring. */
+#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+ ((_r)->sring->rsp_prod - (_r)->rsp_cons)
+
+#ifdef __GNUC__
+#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
+ unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
+ unsigned int rsp = RING_SIZE(_r) - \
+ ((_r)->req_cons - (_r)->rsp_prod_pvt); \
+ req < rsp ? req : rsp; \
+})
+#else
+/* Same as above, but without the nice GCC ({ ... }) syntax. */
+#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
+ ((((_r)->sring->req_prod - (_r)->req_cons) < \
+ (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
+ ((_r)->sring->req_prod - (_r)->req_cons) : \
+ (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
+#endif
+
+/* Direct access to individual ring elements, by index. */
+#define RING_GET_REQUEST(_r, _idx) \
+ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
+
+/*
+ * Get a local copy of a request.
+ *
+ * Use this in preference to RING_GET_REQUEST() so all processing is
+ * done on a local copy that cannot be modified by the other end.
+ *
+ * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
+ * to be ineffective where _req is a struct which consists of only bitfields.
+ */
+#define RING_COPY_REQUEST(_r, _idx, _req) do { \
+ /* Use volatile to force the copy into _req. */ \
+ *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
+} while (0)
+
+#define RING_GET_RESPONSE(_r, _idx) \
+ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
+
+/* Loop termination condition: Would the specified index overflow the ring? */
+#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
+ (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
+
+/* Ill-behaved frontend determination: Can there be this many requests? */
+#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
+ (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
+
+#define RING_PUSH_REQUESTS(_r) do { \
+ xen_wmb(); /* back sees requests /before/ updated producer index */ \
+ (_r)->sring->req_prod = (_r)->req_prod_pvt; \
+} while (0)
+
+#define RING_PUSH_RESPONSES(_r) do { \
+ xen_wmb(); /* front sees resps /before/ updated producer index */ \
+ (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
+} while (0)
+
+/*
+ * Notification hold-off (req_event and rsp_event):
+ *
+ * When queueing requests or responses on a shared ring, it may not always be
+ * necessary to notify the remote end. For example, if requests are in flight
+ * in a backend, the front may be able to queue further requests without
+ * notifying the back (if the back checks for new requests when it queues
+ * responses).
+ *
+ * When enqueuing requests or responses:
+ *
+ * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
+ * is a boolean return value. True indicates that the receiver requires an
+ * asynchronous notification.
+ *
+ * After dequeuing requests or responses (before sleeping the connection):
+ *
+ * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
+ * The second argument is a boolean return value. True indicates that there
+ * are pending messages on the ring (i.e., the connection should not be put
+ * to sleep).
+ *
+ * These macros will set the req_event/rsp_event field to trigger a
+ * notification on the very next message that is enqueued. If you want to
+ * create batches of work (i.e., only receive a notification after several
+ * messages have been enqueued) then you will need to create a customised
+ * version of the FINAL_CHECK macro in your own code, which sets the event
+ * field appropriately.
+ */
+
+#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
+ RING_IDX __old = (_r)->sring->req_prod; \
+ RING_IDX __new = (_r)->req_prod_pvt; \
+ xen_wmb(); /* back sees requests /before/ updated producer index */ \
+ (_r)->sring->req_prod = __new; \
+ xen_mb(); /* back sees new requests /before/ we check req_event */ \
+ (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
+ (RING_IDX)(__new - __old)); \
+} while (0)
+
+#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
+ RING_IDX __old = (_r)->sring->rsp_prod; \
+ RING_IDX __new = (_r)->rsp_prod_pvt; \
+ xen_wmb(); /* front sees resps /before/ updated producer index */ \
+ (_r)->sring->rsp_prod = __new; \
+ xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
+ (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
+ (RING_IDX)(__new - __old)); \
+} while (0)
+
+#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
+ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+ if (_work_to_do) break; \
+ (_r)->sring->req_event = (_r)->req_cons + 1; \
+ xen_mb(); \
+ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+} while (0)
+
+#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
+ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+ if (_work_to_do) break; \
+ (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
+ xen_mb(); \
+ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+} while (0)
+
+
+/*
+ * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
+ * functions to check if there is data on the ring, and to read and
+ * write to them.
+ *
+ * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
+ * does not define the indexes page. As different protocols can have
+ * extensions to the basic format, this macro allow them to define their
+ * own struct.
+ *
+ * XEN_FLEX_RING_SIZE
+ * Convenience macro to calculate the size of one of the two rings
+ * from the overall order.
+ *
+ * $NAME_mask
+ * Function to apply the size mask to an index, to reduce the index
+ * within the range [0-size].
+ *
+ * $NAME_read_packet
+ * Function to read data from the ring. The amount of data to read is
+ * specified by the "size" argument.
+ *
+ * $NAME_write_packet
+ * Function to write data to the ring. The amount of data to write is
+ * specified by the "size" argument.
+ *
+ * $NAME_get_ring_ptr
+ * Convenience function that returns a pointer to read/write to the
+ * ring at the right location.
+ *
+ * $NAME_data_intf
+ * Indexes page, shared between frontend and backend. It also
+ * contains the array of grant refs.
+ *
+ * $NAME_queued
+ * Function to calculate how many bytes are currently on the ring,
+ * ready to be read. It can also be used to calculate how much free
+ * space is currently on the ring (ring_size - $NAME_queued()).
+ */
+#define XEN_FLEX_RING_SIZE(order) \
+ (1UL << (order + PAGE_SHIFT - 1))
+
+#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
+struct name##_data_intf { \
+ RING_IDX in_cons, in_prod; \
+ \
+ uint8_t pad1[56]; \
+ \
+ RING_IDX out_cons, out_prod; \
+ \
+ uint8_t pad2[56]; \
+ \
+ RING_IDX ring_order; \
+ grant_ref_t ref[]; \
+}; \
+DEFINE_XEN_FLEX_RING(name);
+
+#define DEFINE_XEN_FLEX_RING(name) \
+static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
+{ \
+ return (idx & (ring_size - 1)); \
+} \
+ \
+static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
+{ \
+ return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
+} \
+ \
+static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
+ RING_IDX idx, \
+ RING_IDX ring_order) \
+{ \
+ return buf + name##_mask_order(idx, ring_order); \
+} \
+ \
+static inline void name##_read_packet(const unsigned char *buf, \
+ RING_IDX masked_prod, RING_IDX *masked_cons, \
+ RING_IDX ring_size, void *opaque, size_t size) { \
+ if (*masked_cons < masked_prod || \
+ size <= ring_size - *masked_cons) { \
+ memcpy(opaque, buf + *masked_cons, size); \
+ } else { \
+ memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
+ memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
+ size - (ring_size - *masked_cons)); \
+ } \
+ *masked_cons = name##_mask(*masked_cons + size, ring_size); \
+} \
+ \
+static inline void name##_write_packet(unsigned char *buf, \
+ RING_IDX *masked_prod, RING_IDX masked_cons, \
+ RING_IDX ring_size, const void *opaque, size_t size) { \
+ if (*masked_prod < masked_cons || \
+ size <= ring_size - *masked_prod) { \
+ memcpy(buf + *masked_prod, opaque, size); \
+ } else { \
+ memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
+ memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
+ size - (ring_size - *masked_prod)); \
+ } \
+ *masked_prod = name##_mask(*masked_prod + size, ring_size); \
+} \
+ \
+struct name##_data { \
+ unsigned char *in; /* half of the allocation */ \
+ unsigned char *out; /* half of the allocation */ \
+}; \
+ \
+ \
+static inline RING_IDX name##_queued(RING_IDX prod, \
+ RING_IDX cons, RING_IDX ring_size) \
+{ \
+ RING_IDX size; \
+ \
+ if (prod == cons) \
+ return 0; \
+ \
+ prod = name##_mask(prod, ring_size); \
+ cons = name##_mask(cons, ring_size); \
+ \
+ if (prod == cons) \
+ return ring_size; \
+ \
+ if (prod > cons) \
+ size = prod - cons; \
+ else \
+ size = ring_size - (cons - prod); \
+ return size; \
+};
+
+#endif /* __XEN_PUBLIC_IO_RING_H__ */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
--
1.9.1
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Xen-devel@lists.xen.org
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^ permalink raw reply related [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 2/9] xen: import ring.h from xen
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-15 8:00 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 8:00 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini, jgross
[-- Attachment #1: Type: text/plain, Size: 27539 bytes --]
On Mon, 13 Mar 2017 16:55:53 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Do not use the ring.h header installed on the system. Instead, import
> the header into the QEMU codebase. This avoids problems when QEMU is
> built against a Xen version too old to provide all the ring macros.
>
What kind of problems ?
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> ---
> NB: The new macros have not been committed to Xen yet. Do not apply this
> patch until they do.
Why ? Does this break compat with older Xen ?
> ---
> ---
> hw/block/xen_blkif.h | 2 +-
> hw/usb/xen-usb.c | 2 +-
> include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 457 insertions(+), 2 deletions(-)
> create mode 100644 include/hw/xen/io/ring.h
>
> diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> index 3300b6f..3e6e1ea 100644
> --- a/hw/block/xen_blkif.h
> +++ b/hw/block/xen_blkif.h
> @@ -1,7 +1,7 @@
> #ifndef XEN_BLKIF_H
> #define XEN_BLKIF_H
>
> -#include <xen/io/ring.h>
> +#include "hw/xen/io/ring.h"
> #include <xen/io/blkif.h>
> #include <xen/io/protocols.h>
>
> diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> index 8e676e6..370b3d9 100644
> --- a/hw/usb/xen-usb.c
> +++ b/hw/usb/xen-usb.c
> @@ -33,7 +33,7 @@
> #include "qapi/qmp/qint.h"
> #include "qapi/qmp/qstring.h"
>
> -#include <xen/io/ring.h>
> +#include "hw/xen/io/ring.h"
> #include <xen/io/usbif.h>
>
> /*
> diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> new file mode 100644
> index 0000000..cf01fc3
> --- /dev/null
> +++ b/include/hw/xen/io/ring.h
> @@ -0,0 +1,455 @@
> +/******************************************************************************
> + * ring.h
> + *
> + * Shared producer-consumer ring macros.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to
> + * deal in the Software without restriction, including without limitation the
> + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> + * sell copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + * DEALINGS IN THE SOFTWARE.
> + *
> + * Tim Deegan and Andrew Warfield November 2004.
> + */
> +
> +#ifndef __XEN_PUBLIC_IO_RING_H__
> +#define __XEN_PUBLIC_IO_RING_H__
> +
> +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> +#define xen_mb() mb()
> +#define xen_rmb() rmb()
> +#define xen_wmb() wmb()
> +#endif
> +
> +typedef unsigned int RING_IDX;
> +
> +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> +
> +/*
> + * Calculate size of a shared ring, given the total available space for the
> + * ring and indexes (_sz), and the name tag of the request/response structure.
> + * A ring contains as many entries as will fit, rounded down to the nearest
> + * power of two (so we can mask with (size-1) to loop around).
> + */
> +#define __CONST_RING_SIZE(_s, _sz) \
> + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> + sizeof(((struct _s##_sring *)0)->ring[0])))
> +/*
> + * The same for passing in an actual pointer instead of a name tag.
> + */
> +#define __RING_SIZE(_s, _sz) \
> + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> +
> +/*
> + * Macros to make the correct C datatypes for a new kind of ring.
> + *
> + * To make a new ring datatype, you need to have two message structures,
> + * let's say request_t, and response_t already defined.
> + *
> + * In a header where you want the ring datatype declared, you then do:
> + *
> + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> + *
> + * These expand out to give you a set of types, as you can see below.
> + * The most important of these are:
> + *
> + * mytag_sring_t - The shared ring.
> + * mytag_front_ring_t - The 'front' half of the ring.
> + * mytag_back_ring_t - The 'back' half of the ring.
> + *
> + * To initialize a ring in your code you need to know the location and size
> + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> + * the front half:
> + *
> + * mytag_front_ring_t front_ring;
> + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> + *
> + * Initializing the back follows similarly (note that only the front
> + * initializes the shared ring):
> + *
> + * mytag_back_ring_t back_ring;
> + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> + */
> +
> +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> + \
> +/* Shared ring entry */ \
> +union __name##_sring_entry { \
> + __req_t req; \
> + __rsp_t rsp; \
> +}; \
> + \
> +/* Shared ring page */ \
> +struct __name##_sring { \
> + RING_IDX req_prod, req_event; \
> + RING_IDX rsp_prod, rsp_event; \
> + union { \
> + struct { \
> + uint8_t smartpoll_active; \
> + } netif; \
> + struct { \
> + uint8_t msg; \
> + } tapif_user; \
> + uint8_t pvt_pad[4]; \
> + } pvt; \
> + uint8_t __pad[44]; \
> + union __name##_sring_entry ring[1]; /* variable-length */ \
> +}; \
> + \
> +/* "Front" end's private variables */ \
> +struct __name##_front_ring { \
> + RING_IDX req_prod_pvt; \
> + RING_IDX rsp_cons; \
> + unsigned int nr_ents; \
> + struct __name##_sring *sring; \
> +}; \
> + \
> +/* "Back" end's private variables */ \
> +struct __name##_back_ring { \
> + RING_IDX rsp_prod_pvt; \
> + RING_IDX req_cons; \
> + unsigned int nr_ents; \
> + struct __name##_sring *sring; \
> +}; \
> + \
> +/* Syntactic sugar */ \
> +typedef struct __name##_sring __name##_sring_t; \
> +typedef struct __name##_front_ring __name##_front_ring_t; \
> +typedef struct __name##_back_ring __name##_back_ring_t
> +
> +/*
> + * Macros for manipulating rings.
> + *
> + * FRONT_RING_whatever works on the "front end" of a ring: here
> + * requests are pushed on to the ring and responses taken off it.
> + *
> + * BACK_RING_whatever works on the "back end" of a ring: here
> + * requests are taken off the ring and responses put on.
> + *
> + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> + * This is OK in 1-for-1 request-response situations where the
> + * requestor (front end) never has more than RING_SIZE()-1
> + * outstanding requests.
> + */
> +
> +/* Initialising empty rings */
> +#define SHARED_RING_INIT(_s) do { \
> + (_s)->req_prod = (_s)->rsp_prod = 0; \
> + (_s)->req_event = (_s)->rsp_event = 1; \
> + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> +} while(0)
> +
> +#define FRONT_RING_INIT(_r, _s, __size) do { \
> + (_r)->req_prod_pvt = 0; \
> + (_r)->rsp_cons = 0; \
> + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> + (_r)->sring = (_s); \
> +} while (0)
> +
> +#define BACK_RING_INIT(_r, _s, __size) do { \
> + (_r)->rsp_prod_pvt = 0; \
> + (_r)->req_cons = 0; \
> + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> + (_r)->sring = (_s); \
> +} while (0)
> +
> +/* How big is this ring? */
> +#define RING_SIZE(_r) \
> + ((_r)->nr_ents)
> +
> +/* Number of free requests (for use on front side only). */
> +#define RING_FREE_REQUESTS(_r) \
> + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> +
> +/* Test if there is an empty slot available on the front ring.
> + * (This is only meaningful from the front. )
> + */
> +#define RING_FULL(_r) \
> + (RING_FREE_REQUESTS(_r) == 0)
> +
> +/* Test if there are outstanding messages to be processed on a ring. */
> +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> +
> +#ifdef __GNUC__
> +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> + unsigned int rsp = RING_SIZE(_r) - \
> + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> + req < rsp ? req : rsp; \
> +})
> +#else
> +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> + ((_r)->sring->req_prod - (_r)->req_cons) : \
> + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> +#endif
> +
> +/* Direct access to individual ring elements, by index. */
> +#define RING_GET_REQUEST(_r, _idx) \
> + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> +
> +/*
> + * Get a local copy of a request.
> + *
> + * Use this in preference to RING_GET_REQUEST() so all processing is
> + * done on a local copy that cannot be modified by the other end.
> + *
> + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> + * to be ineffective where _req is a struct which consists of only bitfields.
> + */
> +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> + /* Use volatile to force the copy into _req. */ \
> + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> +} while (0)
> +
> +#define RING_GET_RESPONSE(_r, _idx) \
> + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> +
> +/* Loop termination condition: Would the specified index overflow the ring? */
> +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> +
> +/* Ill-behaved frontend determination: Can there be this many requests? */
> +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> +
> +#define RING_PUSH_REQUESTS(_r) do { \
> + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> +} while (0)
> +
> +#define RING_PUSH_RESPONSES(_r) do { \
> + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> +} while (0)
> +
> +/*
> + * Notification hold-off (req_event and rsp_event):
> + *
> + * When queueing requests or responses on a shared ring, it may not always be
> + * necessary to notify the remote end. For example, if requests are in flight
> + * in a backend, the front may be able to queue further requests without
> + * notifying the back (if the back checks for new requests when it queues
> + * responses).
> + *
> + * When enqueuing requests or responses:
> + *
> + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> + * is a boolean return value. True indicates that the receiver requires an
> + * asynchronous notification.
> + *
> + * After dequeuing requests or responses (before sleeping the connection):
> + *
> + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> + * The second argument is a boolean return value. True indicates that there
> + * are pending messages on the ring (i.e., the connection should not be put
> + * to sleep).
> + *
> + * These macros will set the req_event/rsp_event field to trigger a
> + * notification on the very next message that is enqueued. If you want to
> + * create batches of work (i.e., only receive a notification after several
> + * messages have been enqueued) then you will need to create a customised
> + * version of the FINAL_CHECK macro in your own code, which sets the event
> + * field appropriately.
> + */
> +
> +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> + RING_IDX __old = (_r)->sring->req_prod; \
> + RING_IDX __new = (_r)->req_prod_pvt; \
> + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> + (_r)->sring->req_prod = __new; \
> + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> + (RING_IDX)(__new - __old)); \
> +} while (0)
> +
> +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> + RING_IDX __old = (_r)->sring->rsp_prod; \
> + RING_IDX __new = (_r)->rsp_prod_pvt; \
> + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> + (_r)->sring->rsp_prod = __new; \
> + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> + (RING_IDX)(__new - __old)); \
> +} while (0)
> +
> +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> + if (_work_to_do) break; \
> + (_r)->sring->req_event = (_r)->req_cons + 1; \
> + xen_mb(); \
> + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> +} while (0)
> +
> +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> + if (_work_to_do) break; \
> + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> + xen_mb(); \
> + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> +} while (0)
> +
> +
> +/*
> + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> + * functions to check if there is data on the ring, and to read and
> + * write to them.
> + *
> + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> + * does not define the indexes page. As different protocols can have
> + * extensions to the basic format, this macro allow them to define their
> + * own struct.
> + *
> + * XEN_FLEX_RING_SIZE
> + * Convenience macro to calculate the size of one of the two rings
> + * from the overall order.
> + *
> + * $NAME_mask
> + * Function to apply the size mask to an index, to reduce the index
> + * within the range [0-size].
> + *
> + * $NAME_read_packet
> + * Function to read data from the ring. The amount of data to read is
> + * specified by the "size" argument.
> + *
> + * $NAME_write_packet
> + * Function to write data to the ring. The amount of data to write is
> + * specified by the "size" argument.
> + *
> + * $NAME_get_ring_ptr
> + * Convenience function that returns a pointer to read/write to the
> + * ring at the right location.
> + *
> + * $NAME_data_intf
> + * Indexes page, shared between frontend and backend. It also
> + * contains the array of grant refs.
> + *
> + * $NAME_queued
> + * Function to calculate how many bytes are currently on the ring,
> + * ready to be read. It can also be used to calculate how much free
> + * space is currently on the ring (ring_size - $NAME_queued()).
> + */
> +#define XEN_FLEX_RING_SIZE(order) \
> + (1UL << (order + PAGE_SHIFT - 1))
> +
> +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> +struct name##_data_intf { \
> + RING_IDX in_cons, in_prod; \
> + \
> + uint8_t pad1[56]; \
> + \
> + RING_IDX out_cons, out_prod; \
> + \
> + uint8_t pad2[56]; \
> + \
> + RING_IDX ring_order; \
> + grant_ref_t ref[]; \
> +}; \
> +DEFINE_XEN_FLEX_RING(name);
> +
> +#define DEFINE_XEN_FLEX_RING(name) \
> +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> +{ \
> + return (idx & (ring_size - 1)); \
> +} \
> + \
> +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> +{ \
> + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> +} \
> + \
> +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> + RING_IDX idx, \
> + RING_IDX ring_order) \
> +{ \
> + return buf + name##_mask_order(idx, ring_order); \
> +} \
> + \
> +static inline void name##_read_packet(const unsigned char *buf, \
> + RING_IDX masked_prod, RING_IDX *masked_cons, \
> + RING_IDX ring_size, void *opaque, size_t size) { \
> + if (*masked_cons < masked_prod || \
> + size <= ring_size - *masked_cons) { \
> + memcpy(opaque, buf + *masked_cons, size); \
> + } else { \
> + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> + size - (ring_size - *masked_cons)); \
> + } \
> + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> +} \
> + \
> +static inline void name##_write_packet(unsigned char *buf, \
> + RING_IDX *masked_prod, RING_IDX masked_cons, \
> + RING_IDX ring_size, const void *opaque, size_t size) { \
> + if (*masked_prod < masked_cons || \
> + size <= ring_size - *masked_prod) { \
> + memcpy(buf + *masked_prod, opaque, size); \
> + } else { \
> + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> + size - (ring_size - *masked_prod)); \
> + } \
> + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> +} \
> + \
> +struct name##_data { \
> + unsigned char *in; /* half of the allocation */ \
> + unsigned char *out; /* half of the allocation */ \
> +}; \
> + \
> + \
> +static inline RING_IDX name##_queued(RING_IDX prod, \
> + RING_IDX cons, RING_IDX ring_size) \
> +{ \
> + RING_IDX size; \
> + \
> + if (prod == cons) \
> + return 0; \
> + \
> + prod = name##_mask(prod, ring_size); \
> + cons = name##_mask(cons, ring_size); \
> + \
> + if (prod == cons) \
> + return ring_size; \
> + \
> + if (prod > cons) \
> + size = prod - cons; \
> + else \
> + size = ring_size - (cons - prod); \
> + return size; \
> +};
> +
> +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> +
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * tab-width: 4
> + * indent-tabs-mode: nil
> + * End:
> + */
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 2/9] xen: import ring.h from xen
@ 2017-03-15 8:00 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 8:00 UTC (permalink / raw)
To: Stefano Stabellini
Cc: anthony.perard, xen-devel, Stefano Stabellini, qemu-devel, jgross
[-- Attachment #1.1: Type: text/plain, Size: 27539 bytes --]
On Mon, 13 Mar 2017 16:55:53 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Do not use the ring.h header installed on the system. Instead, import
> the header into the QEMU codebase. This avoids problems when QEMU is
> built against a Xen version too old to provide all the ring macros.
>
What kind of problems ?
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> ---
> NB: The new macros have not been committed to Xen yet. Do not apply this
> patch until they do.
Why ? Does this break compat with older Xen ?
> ---
> ---
> hw/block/xen_blkif.h | 2 +-
> hw/usb/xen-usb.c | 2 +-
> include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 457 insertions(+), 2 deletions(-)
> create mode 100644 include/hw/xen/io/ring.h
>
> diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> index 3300b6f..3e6e1ea 100644
> --- a/hw/block/xen_blkif.h
> +++ b/hw/block/xen_blkif.h
> @@ -1,7 +1,7 @@
> #ifndef XEN_BLKIF_H
> #define XEN_BLKIF_H
>
> -#include <xen/io/ring.h>
> +#include "hw/xen/io/ring.h"
> #include <xen/io/blkif.h>
> #include <xen/io/protocols.h>
>
> diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> index 8e676e6..370b3d9 100644
> --- a/hw/usb/xen-usb.c
> +++ b/hw/usb/xen-usb.c
> @@ -33,7 +33,7 @@
> #include "qapi/qmp/qint.h"
> #include "qapi/qmp/qstring.h"
>
> -#include <xen/io/ring.h>
> +#include "hw/xen/io/ring.h"
> #include <xen/io/usbif.h>
>
> /*
> diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> new file mode 100644
> index 0000000..cf01fc3
> --- /dev/null
> +++ b/include/hw/xen/io/ring.h
> @@ -0,0 +1,455 @@
> +/******************************************************************************
> + * ring.h
> + *
> + * Shared producer-consumer ring macros.
> + *
> + * Permission is hereby granted, free of charge, to any person obtaining a copy
> + * of this software and associated documentation files (the "Software"), to
> + * deal in the Software without restriction, including without limitation the
> + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> + * sell copies of the Software, and to permit persons to whom the Software is
> + * furnished to do so, subject to the following conditions:
> + *
> + * The above copyright notice and this permission notice shall be included in
> + * all copies or substantial portions of the Software.
> + *
> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> + * DEALINGS IN THE SOFTWARE.
> + *
> + * Tim Deegan and Andrew Warfield November 2004.
> + */
> +
> +#ifndef __XEN_PUBLIC_IO_RING_H__
> +#define __XEN_PUBLIC_IO_RING_H__
> +
> +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> +#define xen_mb() mb()
> +#define xen_rmb() rmb()
> +#define xen_wmb() wmb()
> +#endif
> +
> +typedef unsigned int RING_IDX;
> +
> +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> +
> +/*
> + * Calculate size of a shared ring, given the total available space for the
> + * ring and indexes (_sz), and the name tag of the request/response structure.
> + * A ring contains as many entries as will fit, rounded down to the nearest
> + * power of two (so we can mask with (size-1) to loop around).
> + */
> +#define __CONST_RING_SIZE(_s, _sz) \
> + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> + sizeof(((struct _s##_sring *)0)->ring[0])))
> +/*
> + * The same for passing in an actual pointer instead of a name tag.
> + */
> +#define __RING_SIZE(_s, _sz) \
> + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> +
> +/*
> + * Macros to make the correct C datatypes for a new kind of ring.
> + *
> + * To make a new ring datatype, you need to have two message structures,
> + * let's say request_t, and response_t already defined.
> + *
> + * In a header where you want the ring datatype declared, you then do:
> + *
> + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> + *
> + * These expand out to give you a set of types, as you can see below.
> + * The most important of these are:
> + *
> + * mytag_sring_t - The shared ring.
> + * mytag_front_ring_t - The 'front' half of the ring.
> + * mytag_back_ring_t - The 'back' half of the ring.
> + *
> + * To initialize a ring in your code you need to know the location and size
> + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> + * the front half:
> + *
> + * mytag_front_ring_t front_ring;
> + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> + *
> + * Initializing the back follows similarly (note that only the front
> + * initializes the shared ring):
> + *
> + * mytag_back_ring_t back_ring;
> + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> + */
> +
> +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> + \
> +/* Shared ring entry */ \
> +union __name##_sring_entry { \
> + __req_t req; \
> + __rsp_t rsp; \
> +}; \
> + \
> +/* Shared ring page */ \
> +struct __name##_sring { \
> + RING_IDX req_prod, req_event; \
> + RING_IDX rsp_prod, rsp_event; \
> + union { \
> + struct { \
> + uint8_t smartpoll_active; \
> + } netif; \
> + struct { \
> + uint8_t msg; \
> + } tapif_user; \
> + uint8_t pvt_pad[4]; \
> + } pvt; \
> + uint8_t __pad[44]; \
> + union __name##_sring_entry ring[1]; /* variable-length */ \
> +}; \
> + \
> +/* "Front" end's private variables */ \
> +struct __name##_front_ring { \
> + RING_IDX req_prod_pvt; \
> + RING_IDX rsp_cons; \
> + unsigned int nr_ents; \
> + struct __name##_sring *sring; \
> +}; \
> + \
> +/* "Back" end's private variables */ \
> +struct __name##_back_ring { \
> + RING_IDX rsp_prod_pvt; \
> + RING_IDX req_cons; \
> + unsigned int nr_ents; \
> + struct __name##_sring *sring; \
> +}; \
> + \
> +/* Syntactic sugar */ \
> +typedef struct __name##_sring __name##_sring_t; \
> +typedef struct __name##_front_ring __name##_front_ring_t; \
> +typedef struct __name##_back_ring __name##_back_ring_t
> +
> +/*
> + * Macros for manipulating rings.
> + *
> + * FRONT_RING_whatever works on the "front end" of a ring: here
> + * requests are pushed on to the ring and responses taken off it.
> + *
> + * BACK_RING_whatever works on the "back end" of a ring: here
> + * requests are taken off the ring and responses put on.
> + *
> + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> + * This is OK in 1-for-1 request-response situations where the
> + * requestor (front end) never has more than RING_SIZE()-1
> + * outstanding requests.
> + */
> +
> +/* Initialising empty rings */
> +#define SHARED_RING_INIT(_s) do { \
> + (_s)->req_prod = (_s)->rsp_prod = 0; \
> + (_s)->req_event = (_s)->rsp_event = 1; \
> + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> +} while(0)
> +
> +#define FRONT_RING_INIT(_r, _s, __size) do { \
> + (_r)->req_prod_pvt = 0; \
> + (_r)->rsp_cons = 0; \
> + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> + (_r)->sring = (_s); \
> +} while (0)
> +
> +#define BACK_RING_INIT(_r, _s, __size) do { \
> + (_r)->rsp_prod_pvt = 0; \
> + (_r)->req_cons = 0; \
> + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> + (_r)->sring = (_s); \
> +} while (0)
> +
> +/* How big is this ring? */
> +#define RING_SIZE(_r) \
> + ((_r)->nr_ents)
> +
> +/* Number of free requests (for use on front side only). */
> +#define RING_FREE_REQUESTS(_r) \
> + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> +
> +/* Test if there is an empty slot available on the front ring.
> + * (This is only meaningful from the front. )
> + */
> +#define RING_FULL(_r) \
> + (RING_FREE_REQUESTS(_r) == 0)
> +
> +/* Test if there are outstanding messages to be processed on a ring. */
> +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> +
> +#ifdef __GNUC__
> +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> + unsigned int rsp = RING_SIZE(_r) - \
> + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> + req < rsp ? req : rsp; \
> +})
> +#else
> +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> + ((_r)->sring->req_prod - (_r)->req_cons) : \
> + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> +#endif
> +
> +/* Direct access to individual ring elements, by index. */
> +#define RING_GET_REQUEST(_r, _idx) \
> + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> +
> +/*
> + * Get a local copy of a request.
> + *
> + * Use this in preference to RING_GET_REQUEST() so all processing is
> + * done on a local copy that cannot be modified by the other end.
> + *
> + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> + * to be ineffective where _req is a struct which consists of only bitfields.
> + */
> +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> + /* Use volatile to force the copy into _req. */ \
> + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> +} while (0)
> +
> +#define RING_GET_RESPONSE(_r, _idx) \
> + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> +
> +/* Loop termination condition: Would the specified index overflow the ring? */
> +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> +
> +/* Ill-behaved frontend determination: Can there be this many requests? */
> +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> +
> +#define RING_PUSH_REQUESTS(_r) do { \
> + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> +} while (0)
> +
> +#define RING_PUSH_RESPONSES(_r) do { \
> + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> +} while (0)
> +
> +/*
> + * Notification hold-off (req_event and rsp_event):
> + *
> + * When queueing requests or responses on a shared ring, it may not always be
> + * necessary to notify the remote end. For example, if requests are in flight
> + * in a backend, the front may be able to queue further requests without
> + * notifying the back (if the back checks for new requests when it queues
> + * responses).
> + *
> + * When enqueuing requests or responses:
> + *
> + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> + * is a boolean return value. True indicates that the receiver requires an
> + * asynchronous notification.
> + *
> + * After dequeuing requests or responses (before sleeping the connection):
> + *
> + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> + * The second argument is a boolean return value. True indicates that there
> + * are pending messages on the ring (i.e., the connection should not be put
> + * to sleep).
> + *
> + * These macros will set the req_event/rsp_event field to trigger a
> + * notification on the very next message that is enqueued. If you want to
> + * create batches of work (i.e., only receive a notification after several
> + * messages have been enqueued) then you will need to create a customised
> + * version of the FINAL_CHECK macro in your own code, which sets the event
> + * field appropriately.
> + */
> +
> +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> + RING_IDX __old = (_r)->sring->req_prod; \
> + RING_IDX __new = (_r)->req_prod_pvt; \
> + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> + (_r)->sring->req_prod = __new; \
> + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> + (RING_IDX)(__new - __old)); \
> +} while (0)
> +
> +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> + RING_IDX __old = (_r)->sring->rsp_prod; \
> + RING_IDX __new = (_r)->rsp_prod_pvt; \
> + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> + (_r)->sring->rsp_prod = __new; \
> + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> + (RING_IDX)(__new - __old)); \
> +} while (0)
> +
> +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> + if (_work_to_do) break; \
> + (_r)->sring->req_event = (_r)->req_cons + 1; \
> + xen_mb(); \
> + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> +} while (0)
> +
> +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> + if (_work_to_do) break; \
> + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> + xen_mb(); \
> + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> +} while (0)
> +
> +
> +/*
> + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> + * functions to check if there is data on the ring, and to read and
> + * write to them.
> + *
> + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> + * does not define the indexes page. As different protocols can have
> + * extensions to the basic format, this macro allow them to define their
> + * own struct.
> + *
> + * XEN_FLEX_RING_SIZE
> + * Convenience macro to calculate the size of one of the two rings
> + * from the overall order.
> + *
> + * $NAME_mask
> + * Function to apply the size mask to an index, to reduce the index
> + * within the range [0-size].
> + *
> + * $NAME_read_packet
> + * Function to read data from the ring. The amount of data to read is
> + * specified by the "size" argument.
> + *
> + * $NAME_write_packet
> + * Function to write data to the ring. The amount of data to write is
> + * specified by the "size" argument.
> + *
> + * $NAME_get_ring_ptr
> + * Convenience function that returns a pointer to read/write to the
> + * ring at the right location.
> + *
> + * $NAME_data_intf
> + * Indexes page, shared between frontend and backend. It also
> + * contains the array of grant refs.
> + *
> + * $NAME_queued
> + * Function to calculate how many bytes are currently on the ring,
> + * ready to be read. It can also be used to calculate how much free
> + * space is currently on the ring (ring_size - $NAME_queued()).
> + */
> +#define XEN_FLEX_RING_SIZE(order) \
> + (1UL << (order + PAGE_SHIFT - 1))
> +
> +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> +struct name##_data_intf { \
> + RING_IDX in_cons, in_prod; \
> + \
> + uint8_t pad1[56]; \
> + \
> + RING_IDX out_cons, out_prod; \
> + \
> + uint8_t pad2[56]; \
> + \
> + RING_IDX ring_order; \
> + grant_ref_t ref[]; \
> +}; \
> +DEFINE_XEN_FLEX_RING(name);
> +
> +#define DEFINE_XEN_FLEX_RING(name) \
> +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> +{ \
> + return (idx & (ring_size - 1)); \
> +} \
> + \
> +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> +{ \
> + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> +} \
> + \
> +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> + RING_IDX idx, \
> + RING_IDX ring_order) \
> +{ \
> + return buf + name##_mask_order(idx, ring_order); \
> +} \
> + \
> +static inline void name##_read_packet(const unsigned char *buf, \
> + RING_IDX masked_prod, RING_IDX *masked_cons, \
> + RING_IDX ring_size, void *opaque, size_t size) { \
> + if (*masked_cons < masked_prod || \
> + size <= ring_size - *masked_cons) { \
> + memcpy(opaque, buf + *masked_cons, size); \
> + } else { \
> + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> + size - (ring_size - *masked_cons)); \
> + } \
> + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> +} \
> + \
> +static inline void name##_write_packet(unsigned char *buf, \
> + RING_IDX *masked_prod, RING_IDX masked_cons, \
> + RING_IDX ring_size, const void *opaque, size_t size) { \
> + if (*masked_prod < masked_cons || \
> + size <= ring_size - *masked_prod) { \
> + memcpy(buf + *masked_prod, opaque, size); \
> + } else { \
> + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> + size - (ring_size - *masked_prod)); \
> + } \
> + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> +} \
> + \
> +struct name##_data { \
> + unsigned char *in; /* half of the allocation */ \
> + unsigned char *out; /* half of the allocation */ \
> +}; \
> + \
> + \
> +static inline RING_IDX name##_queued(RING_IDX prod, \
> + RING_IDX cons, RING_IDX ring_size) \
> +{ \
> + RING_IDX size; \
> + \
> + if (prod == cons) \
> + return 0; \
> + \
> + prod = name##_mask(prod, ring_size); \
> + cons = name##_mask(cons, ring_size); \
> + \
> + if (prod == cons) \
> + return ring_size; \
> + \
> + if (prod > cons) \
> + size = prod - cons; \
> + else \
> + size = ring_size - (cons - prod); \
> + return size; \
> +};
> +
> +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> +
> +/*
> + * Local variables:
> + * mode: C
> + * c-file-style: "BSD"
> + * c-basic-offset: 4
> + * tab-width: 4
> + * indent-tabs-mode: nil
> + * End:
> + */
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 2/9] xen: import ring.h from xen
2017-03-15 8:00 ` Greg Kurz
@ 2017-03-15 18:36 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 18:36 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard,
Stefano Stabellini, jgross
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:53 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Do not use the ring.h header installed on the system. Instead, import
> > the header into the QEMU codebase. This avoids problems when QEMU is
> > built against a Xen version too old to provide all the ring macros.
> >
>
> What kind of problems ?
The FLEX macros are only available in Xen 4.9+ (still unreleased).
However, aside from these macros, the Xen 9pfs frontends and backends
could work fine on any Xen releases. In fact, the Xen public/io headers
are only provided as reference.
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > ---
> > NB: The new macros have not been committed to Xen yet. Do not apply this
> > patch until they do.
>
> Why ? Does this break compat with older Xen ?
No, it does not break compatibility. But I think it is a good idea to
commit the header to QEMU only after the corresponding Xen header has
been accepted. I don't want the two to diverge.
> > ---
> > ---
> > hw/block/xen_blkif.h | 2 +-
> > hw/usb/xen-usb.c | 2 +-
> > include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 457 insertions(+), 2 deletions(-)
> > create mode 100644 include/hw/xen/io/ring.h
> >
> > diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> > index 3300b6f..3e6e1ea 100644
> > --- a/hw/block/xen_blkif.h
> > +++ b/hw/block/xen_blkif.h
> > @@ -1,7 +1,7 @@
> > #ifndef XEN_BLKIF_H
> > #define XEN_BLKIF_H
> >
> > -#include <xen/io/ring.h>
> > +#include "hw/xen/io/ring.h"
> > #include <xen/io/blkif.h>
> > #include <xen/io/protocols.h>
> >
> > diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> > index 8e676e6..370b3d9 100644
> > --- a/hw/usb/xen-usb.c
> > +++ b/hw/usb/xen-usb.c
> > @@ -33,7 +33,7 @@
> > #include "qapi/qmp/qint.h"
> > #include "qapi/qmp/qstring.h"
> >
> > -#include <xen/io/ring.h>
> > +#include "hw/xen/io/ring.h"
> > #include <xen/io/usbif.h>
> >
> > /*
> > diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> > new file mode 100644
> > index 0000000..cf01fc3
> > --- /dev/null
> > +++ b/include/hw/xen/io/ring.h
> > @@ -0,0 +1,455 @@
> > +/******************************************************************************
> > + * ring.h
> > + *
> > + * Shared producer-consumer ring macros.
> > + *
> > + * Permission is hereby granted, free of charge, to any person obtaining a copy
> > + * of this software and associated documentation files (the "Software"), to
> > + * deal in the Software without restriction, including without limitation the
> > + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> > + * sell copies of the Software, and to permit persons to whom the Software is
> > + * furnished to do so, subject to the following conditions:
> > + *
> > + * The above copyright notice and this permission notice shall be included in
> > + * all copies or substantial portions of the Software.
> > + *
> > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> > + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> > + * DEALINGS IN THE SOFTWARE.
> > + *
> > + * Tim Deegan and Andrew Warfield November 2004.
> > + */
> > +
> > +#ifndef __XEN_PUBLIC_IO_RING_H__
> > +#define __XEN_PUBLIC_IO_RING_H__
> > +
> > +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> > +#define xen_mb() mb()
> > +#define xen_rmb() rmb()
> > +#define xen_wmb() wmb()
> > +#endif
> > +
> > +typedef unsigned int RING_IDX;
> > +
> > +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> > +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> > +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> > +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> > +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> > +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> > +
> > +/*
> > + * Calculate size of a shared ring, given the total available space for the
> > + * ring and indexes (_sz), and the name tag of the request/response structure.
> > + * A ring contains as many entries as will fit, rounded down to the nearest
> > + * power of two (so we can mask with (size-1) to loop around).
> > + */
> > +#define __CONST_RING_SIZE(_s, _sz) \
> > + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> > + sizeof(((struct _s##_sring *)0)->ring[0])))
> > +/*
> > + * The same for passing in an actual pointer instead of a name tag.
> > + */
> > +#define __RING_SIZE(_s, _sz) \
> > + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> > +
> > +/*
> > + * Macros to make the correct C datatypes for a new kind of ring.
> > + *
> > + * To make a new ring datatype, you need to have two message structures,
> > + * let's say request_t, and response_t already defined.
> > + *
> > + * In a header where you want the ring datatype declared, you then do:
> > + *
> > + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> > + *
> > + * These expand out to give you a set of types, as you can see below.
> > + * The most important of these are:
> > + *
> > + * mytag_sring_t - The shared ring.
> > + * mytag_front_ring_t - The 'front' half of the ring.
> > + * mytag_back_ring_t - The 'back' half of the ring.
> > + *
> > + * To initialize a ring in your code you need to know the location and size
> > + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> > + * the front half:
> > + *
> > + * mytag_front_ring_t front_ring;
> > + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> > + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > + *
> > + * Initializing the back follows similarly (note that only the front
> > + * initializes the shared ring):
> > + *
> > + * mytag_back_ring_t back_ring;
> > + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > + */
> > +
> > +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> > + \
> > +/* Shared ring entry */ \
> > +union __name##_sring_entry { \
> > + __req_t req; \
> > + __rsp_t rsp; \
> > +}; \
> > + \
> > +/* Shared ring page */ \
> > +struct __name##_sring { \
> > + RING_IDX req_prod, req_event; \
> > + RING_IDX rsp_prod, rsp_event; \
> > + union { \
> > + struct { \
> > + uint8_t smartpoll_active; \
> > + } netif; \
> > + struct { \
> > + uint8_t msg; \
> > + } tapif_user; \
> > + uint8_t pvt_pad[4]; \
> > + } pvt; \
> > + uint8_t __pad[44]; \
> > + union __name##_sring_entry ring[1]; /* variable-length */ \
> > +}; \
> > + \
> > +/* "Front" end's private variables */ \
> > +struct __name##_front_ring { \
> > + RING_IDX req_prod_pvt; \
> > + RING_IDX rsp_cons; \
> > + unsigned int nr_ents; \
> > + struct __name##_sring *sring; \
> > +}; \
> > + \
> > +/* "Back" end's private variables */ \
> > +struct __name##_back_ring { \
> > + RING_IDX rsp_prod_pvt; \
> > + RING_IDX req_cons; \
> > + unsigned int nr_ents; \
> > + struct __name##_sring *sring; \
> > +}; \
> > + \
> > +/* Syntactic sugar */ \
> > +typedef struct __name##_sring __name##_sring_t; \
> > +typedef struct __name##_front_ring __name##_front_ring_t; \
> > +typedef struct __name##_back_ring __name##_back_ring_t
> > +
> > +/*
> > + * Macros for manipulating rings.
> > + *
> > + * FRONT_RING_whatever works on the "front end" of a ring: here
> > + * requests are pushed on to the ring and responses taken off it.
> > + *
> > + * BACK_RING_whatever works on the "back end" of a ring: here
> > + * requests are taken off the ring and responses put on.
> > + *
> > + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> > + * This is OK in 1-for-1 request-response situations where the
> > + * requestor (front end) never has more than RING_SIZE()-1
> > + * outstanding requests.
> > + */
> > +
> > +/* Initialising empty rings */
> > +#define SHARED_RING_INIT(_s) do { \
> > + (_s)->req_prod = (_s)->rsp_prod = 0; \
> > + (_s)->req_event = (_s)->rsp_event = 1; \
> > + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> > + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> > +} while(0)
> > +
> > +#define FRONT_RING_INIT(_r, _s, __size) do { \
> > + (_r)->req_prod_pvt = 0; \
> > + (_r)->rsp_cons = 0; \
> > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > + (_r)->sring = (_s); \
> > +} while (0)
> > +
> > +#define BACK_RING_INIT(_r, _s, __size) do { \
> > + (_r)->rsp_prod_pvt = 0; \
> > + (_r)->req_cons = 0; \
> > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > + (_r)->sring = (_s); \
> > +} while (0)
> > +
> > +/* How big is this ring? */
> > +#define RING_SIZE(_r) \
> > + ((_r)->nr_ents)
> > +
> > +/* Number of free requests (for use on front side only). */
> > +#define RING_FREE_REQUESTS(_r) \
> > + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> > +
> > +/* Test if there is an empty slot available on the front ring.
> > + * (This is only meaningful from the front. )
> > + */
> > +#define RING_FULL(_r) \
> > + (RING_FREE_REQUESTS(_r) == 0)
> > +
> > +/* Test if there are outstanding messages to be processed on a ring. */
> > +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> > + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> > +
> > +#ifdef __GNUC__
> > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> > + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> > + unsigned int rsp = RING_SIZE(_r) - \
> > + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> > + req < rsp ? req : rsp; \
> > +})
> > +#else
> > +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> > + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> > + ((_r)->sring->req_prod - (_r)->req_cons) : \
> > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> > +#endif
> > +
> > +/* Direct access to individual ring elements, by index. */
> > +#define RING_GET_REQUEST(_r, _idx) \
> > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> > +
> > +/*
> > + * Get a local copy of a request.
> > + *
> > + * Use this in preference to RING_GET_REQUEST() so all processing is
> > + * done on a local copy that cannot be modified by the other end.
> > + *
> > + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> > + * to be ineffective where _req is a struct which consists of only bitfields.
> > + */
> > +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> > + /* Use volatile to force the copy into _req. */ \
> > + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> > +} while (0)
> > +
> > +#define RING_GET_RESPONSE(_r, _idx) \
> > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> > +
> > +/* Loop termination condition: Would the specified index overflow the ring? */
> > +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> > + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> > +
> > +/* Ill-behaved frontend determination: Can there be this many requests? */
> > +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> > + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> > +
> > +#define RING_PUSH_REQUESTS(_r) do { \
> > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> > +} while (0)
> > +
> > +#define RING_PUSH_RESPONSES(_r) do { \
> > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> > +} while (0)
> > +
> > +/*
> > + * Notification hold-off (req_event and rsp_event):
> > + *
> > + * When queueing requests or responses on a shared ring, it may not always be
> > + * necessary to notify the remote end. For example, if requests are in flight
> > + * in a backend, the front may be able to queue further requests without
> > + * notifying the back (if the back checks for new requests when it queues
> > + * responses).
> > + *
> > + * When enqueuing requests or responses:
> > + *
> > + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> > + * is a boolean return value. True indicates that the receiver requires an
> > + * asynchronous notification.
> > + *
> > + * After dequeuing requests or responses (before sleeping the connection):
> > + *
> > + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> > + * The second argument is a boolean return value. True indicates that there
> > + * are pending messages on the ring (i.e., the connection should not be put
> > + * to sleep).
> > + *
> > + * These macros will set the req_event/rsp_event field to trigger a
> > + * notification on the very next message that is enqueued. If you want to
> > + * create batches of work (i.e., only receive a notification after several
> > + * messages have been enqueued) then you will need to create a customised
> > + * version of the FINAL_CHECK macro in your own code, which sets the event
> > + * field appropriately.
> > + */
> > +
> > +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> > + RING_IDX __old = (_r)->sring->req_prod; \
> > + RING_IDX __new = (_r)->req_prod_pvt; \
> > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > + (_r)->sring->req_prod = __new; \
> > + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> > + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> > + (RING_IDX)(__new - __old)); \
> > +} while (0)
> > +
> > +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> > + RING_IDX __old = (_r)->sring->rsp_prod; \
> > + RING_IDX __new = (_r)->rsp_prod_pvt; \
> > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > + (_r)->sring->rsp_prod = __new; \
> > + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> > + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> > + (RING_IDX)(__new - __old)); \
> > +} while (0)
> > +
> > +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > + if (_work_to_do) break; \
> > + (_r)->sring->req_event = (_r)->req_cons + 1; \
> > + xen_mb(); \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > +} while (0)
> > +
> > +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > + if (_work_to_do) break; \
> > + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> > + xen_mb(); \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > +} while (0)
> > +
> > +
> > +/*
> > + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> > + * functions to check if there is data on the ring, and to read and
> > + * write to them.
> > + *
> > + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> > + * does not define the indexes page. As different protocols can have
> > + * extensions to the basic format, this macro allow them to define their
> > + * own struct.
> > + *
> > + * XEN_FLEX_RING_SIZE
> > + * Convenience macro to calculate the size of one of the two rings
> > + * from the overall order.
> > + *
> > + * $NAME_mask
> > + * Function to apply the size mask to an index, to reduce the index
> > + * within the range [0-size].
> > + *
> > + * $NAME_read_packet
> > + * Function to read data from the ring. The amount of data to read is
> > + * specified by the "size" argument.
> > + *
> > + * $NAME_write_packet
> > + * Function to write data to the ring. The amount of data to write is
> > + * specified by the "size" argument.
> > + *
> > + * $NAME_get_ring_ptr
> > + * Convenience function that returns a pointer to read/write to the
> > + * ring at the right location.
> > + *
> > + * $NAME_data_intf
> > + * Indexes page, shared between frontend and backend. It also
> > + * contains the array of grant refs.
> > + *
> > + * $NAME_queued
> > + * Function to calculate how many bytes are currently on the ring,
> > + * ready to be read. It can also be used to calculate how much free
> > + * space is currently on the ring (ring_size - $NAME_queued()).
> > + */
> > +#define XEN_FLEX_RING_SIZE(order) \
> > + (1UL << (order + PAGE_SHIFT - 1))
> > +
> > +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> > +struct name##_data_intf { \
> > + RING_IDX in_cons, in_prod; \
> > + \
> > + uint8_t pad1[56]; \
> > + \
> > + RING_IDX out_cons, out_prod; \
> > + \
> > + uint8_t pad2[56]; \
> > + \
> > + RING_IDX ring_order; \
> > + grant_ref_t ref[]; \
> > +}; \
> > +DEFINE_XEN_FLEX_RING(name);
> > +
> > +#define DEFINE_XEN_FLEX_RING(name) \
> > +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> > +{ \
> > + return (idx & (ring_size - 1)); \
> > +} \
> > + \
> > +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> > +{ \
> > + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> > +} \
> > + \
> > +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> > + RING_IDX idx, \
> > + RING_IDX ring_order) \
> > +{ \
> > + return buf + name##_mask_order(idx, ring_order); \
> > +} \
> > + \
> > +static inline void name##_read_packet(const unsigned char *buf, \
> > + RING_IDX masked_prod, RING_IDX *masked_cons, \
> > + RING_IDX ring_size, void *opaque, size_t size) { \
> > + if (*masked_cons < masked_prod || \
> > + size <= ring_size - *masked_cons) { \
> > + memcpy(opaque, buf + *masked_cons, size); \
> > + } else { \
> > + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> > + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> > + size - (ring_size - *masked_cons)); \
> > + } \
> > + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> > +} \
> > + \
> > +static inline void name##_write_packet(unsigned char *buf, \
> > + RING_IDX *masked_prod, RING_IDX masked_cons, \
> > + RING_IDX ring_size, const void *opaque, size_t size) { \
> > + if (*masked_prod < masked_cons || \
> > + size <= ring_size - *masked_prod) { \
> > + memcpy(buf + *masked_prod, opaque, size); \
> > + } else { \
> > + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> > + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> > + size - (ring_size - *masked_prod)); \
> > + } \
> > + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> > +} \
> > + \
> > +struct name##_data { \
> > + unsigned char *in; /* half of the allocation */ \
> > + unsigned char *out; /* half of the allocation */ \
> > +}; \
> > + \
> > + \
> > +static inline RING_IDX name##_queued(RING_IDX prod, \
> > + RING_IDX cons, RING_IDX ring_size) \
> > +{ \
> > + RING_IDX size; \
> > + \
> > + if (prod == cons) \
> > + return 0; \
> > + \
> > + prod = name##_mask(prod, ring_size); \
> > + cons = name##_mask(cons, ring_size); \
> > + \
> > + if (prod == cons) \
> > + return ring_size; \
> > + \
> > + if (prod > cons) \
> > + size = prod - cons; \
> > + else \
> > + size = ring_size - (cons - prod); \
> > + return size; \
> > +};
> > +
> > +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> > +
> > +/*
> > + * Local variables:
> > + * mode: C
> > + * c-file-style: "BSD"
> > + * c-basic-offset: 4
> > + * tab-width: 4
> > + * indent-tabs-mode: nil
> > + * End:
> > + */
>
>
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 2/9] xen: import ring.h from xen
@ 2017-03-15 18:36 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 18:36 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:53 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Do not use the ring.h header installed on the system. Instead, import
> > the header into the QEMU codebase. This avoids problems when QEMU is
> > built against a Xen version too old to provide all the ring macros.
> >
>
> What kind of problems ?
The FLEX macros are only available in Xen 4.9+ (still unreleased).
However, aside from these macros, the Xen 9pfs frontends and backends
could work fine on any Xen releases. In fact, the Xen public/io headers
are only provided as reference.
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > ---
> > NB: The new macros have not been committed to Xen yet. Do not apply this
> > patch until they do.
>
> Why ? Does this break compat with older Xen ?
No, it does not break compatibility. But I think it is a good idea to
commit the header to QEMU only after the corresponding Xen header has
been accepted. I don't want the two to diverge.
> > ---
> > ---
> > hw/block/xen_blkif.h | 2 +-
> > hw/usb/xen-usb.c | 2 +-
> > include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 457 insertions(+), 2 deletions(-)
> > create mode 100644 include/hw/xen/io/ring.h
> >
> > diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> > index 3300b6f..3e6e1ea 100644
> > --- a/hw/block/xen_blkif.h
> > +++ b/hw/block/xen_blkif.h
> > @@ -1,7 +1,7 @@
> > #ifndef XEN_BLKIF_H
> > #define XEN_BLKIF_H
> >
> > -#include <xen/io/ring.h>
> > +#include "hw/xen/io/ring.h"
> > #include <xen/io/blkif.h>
> > #include <xen/io/protocols.h>
> >
> > diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> > index 8e676e6..370b3d9 100644
> > --- a/hw/usb/xen-usb.c
> > +++ b/hw/usb/xen-usb.c
> > @@ -33,7 +33,7 @@
> > #include "qapi/qmp/qint.h"
> > #include "qapi/qmp/qstring.h"
> >
> > -#include <xen/io/ring.h>
> > +#include "hw/xen/io/ring.h"
> > #include <xen/io/usbif.h>
> >
> > /*
> > diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> > new file mode 100644
> > index 0000000..cf01fc3
> > --- /dev/null
> > +++ b/include/hw/xen/io/ring.h
> > @@ -0,0 +1,455 @@
> > +/******************************************************************************
> > + * ring.h
> > + *
> > + * Shared producer-consumer ring macros.
> > + *
> > + * Permission is hereby granted, free of charge, to any person obtaining a copy
> > + * of this software and associated documentation files (the "Software"), to
> > + * deal in the Software without restriction, including without limitation the
> > + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> > + * sell copies of the Software, and to permit persons to whom the Software is
> > + * furnished to do so, subject to the following conditions:
> > + *
> > + * The above copyright notice and this permission notice shall be included in
> > + * all copies or substantial portions of the Software.
> > + *
> > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> > + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> > + * DEALINGS IN THE SOFTWARE.
> > + *
> > + * Tim Deegan and Andrew Warfield November 2004.
> > + */
> > +
> > +#ifndef __XEN_PUBLIC_IO_RING_H__
> > +#define __XEN_PUBLIC_IO_RING_H__
> > +
> > +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> > +#define xen_mb() mb()
> > +#define xen_rmb() rmb()
> > +#define xen_wmb() wmb()
> > +#endif
> > +
> > +typedef unsigned int RING_IDX;
> > +
> > +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> > +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> > +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> > +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> > +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> > +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> > +
> > +/*
> > + * Calculate size of a shared ring, given the total available space for the
> > + * ring and indexes (_sz), and the name tag of the request/response structure.
> > + * A ring contains as many entries as will fit, rounded down to the nearest
> > + * power of two (so we can mask with (size-1) to loop around).
> > + */
> > +#define __CONST_RING_SIZE(_s, _sz) \
> > + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> > + sizeof(((struct _s##_sring *)0)->ring[0])))
> > +/*
> > + * The same for passing in an actual pointer instead of a name tag.
> > + */
> > +#define __RING_SIZE(_s, _sz) \
> > + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> > +
> > +/*
> > + * Macros to make the correct C datatypes for a new kind of ring.
> > + *
> > + * To make a new ring datatype, you need to have two message structures,
> > + * let's say request_t, and response_t already defined.
> > + *
> > + * In a header where you want the ring datatype declared, you then do:
> > + *
> > + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> > + *
> > + * These expand out to give you a set of types, as you can see below.
> > + * The most important of these are:
> > + *
> > + * mytag_sring_t - The shared ring.
> > + * mytag_front_ring_t - The 'front' half of the ring.
> > + * mytag_back_ring_t - The 'back' half of the ring.
> > + *
> > + * To initialize a ring in your code you need to know the location and size
> > + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> > + * the front half:
> > + *
> > + * mytag_front_ring_t front_ring;
> > + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> > + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > + *
> > + * Initializing the back follows similarly (note that only the front
> > + * initializes the shared ring):
> > + *
> > + * mytag_back_ring_t back_ring;
> > + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > + */
> > +
> > +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> > + \
> > +/* Shared ring entry */ \
> > +union __name##_sring_entry { \
> > + __req_t req; \
> > + __rsp_t rsp; \
> > +}; \
> > + \
> > +/* Shared ring page */ \
> > +struct __name##_sring { \
> > + RING_IDX req_prod, req_event; \
> > + RING_IDX rsp_prod, rsp_event; \
> > + union { \
> > + struct { \
> > + uint8_t smartpoll_active; \
> > + } netif; \
> > + struct { \
> > + uint8_t msg; \
> > + } tapif_user; \
> > + uint8_t pvt_pad[4]; \
> > + } pvt; \
> > + uint8_t __pad[44]; \
> > + union __name##_sring_entry ring[1]; /* variable-length */ \
> > +}; \
> > + \
> > +/* "Front" end's private variables */ \
> > +struct __name##_front_ring { \
> > + RING_IDX req_prod_pvt; \
> > + RING_IDX rsp_cons; \
> > + unsigned int nr_ents; \
> > + struct __name##_sring *sring; \
> > +}; \
> > + \
> > +/* "Back" end's private variables */ \
> > +struct __name##_back_ring { \
> > + RING_IDX rsp_prod_pvt; \
> > + RING_IDX req_cons; \
> > + unsigned int nr_ents; \
> > + struct __name##_sring *sring; \
> > +}; \
> > + \
> > +/* Syntactic sugar */ \
> > +typedef struct __name##_sring __name##_sring_t; \
> > +typedef struct __name##_front_ring __name##_front_ring_t; \
> > +typedef struct __name##_back_ring __name##_back_ring_t
> > +
> > +/*
> > + * Macros for manipulating rings.
> > + *
> > + * FRONT_RING_whatever works on the "front end" of a ring: here
> > + * requests are pushed on to the ring and responses taken off it.
> > + *
> > + * BACK_RING_whatever works on the "back end" of a ring: here
> > + * requests are taken off the ring and responses put on.
> > + *
> > + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> > + * This is OK in 1-for-1 request-response situations where the
> > + * requestor (front end) never has more than RING_SIZE()-1
> > + * outstanding requests.
> > + */
> > +
> > +/* Initialising empty rings */
> > +#define SHARED_RING_INIT(_s) do { \
> > + (_s)->req_prod = (_s)->rsp_prod = 0; \
> > + (_s)->req_event = (_s)->rsp_event = 1; \
> > + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> > + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> > +} while(0)
> > +
> > +#define FRONT_RING_INIT(_r, _s, __size) do { \
> > + (_r)->req_prod_pvt = 0; \
> > + (_r)->rsp_cons = 0; \
> > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > + (_r)->sring = (_s); \
> > +} while (0)
> > +
> > +#define BACK_RING_INIT(_r, _s, __size) do { \
> > + (_r)->rsp_prod_pvt = 0; \
> > + (_r)->req_cons = 0; \
> > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > + (_r)->sring = (_s); \
> > +} while (0)
> > +
> > +/* How big is this ring? */
> > +#define RING_SIZE(_r) \
> > + ((_r)->nr_ents)
> > +
> > +/* Number of free requests (for use on front side only). */
> > +#define RING_FREE_REQUESTS(_r) \
> > + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> > +
> > +/* Test if there is an empty slot available on the front ring.
> > + * (This is only meaningful from the front. )
> > + */
> > +#define RING_FULL(_r) \
> > + (RING_FREE_REQUESTS(_r) == 0)
> > +
> > +/* Test if there are outstanding messages to be processed on a ring. */
> > +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> > + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> > +
> > +#ifdef __GNUC__
> > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> > + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> > + unsigned int rsp = RING_SIZE(_r) - \
> > + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> > + req < rsp ? req : rsp; \
> > +})
> > +#else
> > +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> > + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> > + ((_r)->sring->req_prod - (_r)->req_cons) : \
> > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> > +#endif
> > +
> > +/* Direct access to individual ring elements, by index. */
> > +#define RING_GET_REQUEST(_r, _idx) \
> > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> > +
> > +/*
> > + * Get a local copy of a request.
> > + *
> > + * Use this in preference to RING_GET_REQUEST() so all processing is
> > + * done on a local copy that cannot be modified by the other end.
> > + *
> > + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> > + * to be ineffective where _req is a struct which consists of only bitfields.
> > + */
> > +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> > + /* Use volatile to force the copy into _req. */ \
> > + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> > +} while (0)
> > +
> > +#define RING_GET_RESPONSE(_r, _idx) \
> > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> > +
> > +/* Loop termination condition: Would the specified index overflow the ring? */
> > +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> > + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> > +
> > +/* Ill-behaved frontend determination: Can there be this many requests? */
> > +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> > + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> > +
> > +#define RING_PUSH_REQUESTS(_r) do { \
> > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> > +} while (0)
> > +
> > +#define RING_PUSH_RESPONSES(_r) do { \
> > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> > +} while (0)
> > +
> > +/*
> > + * Notification hold-off (req_event and rsp_event):
> > + *
> > + * When queueing requests or responses on a shared ring, it may not always be
> > + * necessary to notify the remote end. For example, if requests are in flight
> > + * in a backend, the front may be able to queue further requests without
> > + * notifying the back (if the back checks for new requests when it queues
> > + * responses).
> > + *
> > + * When enqueuing requests or responses:
> > + *
> > + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> > + * is a boolean return value. True indicates that the receiver requires an
> > + * asynchronous notification.
> > + *
> > + * After dequeuing requests or responses (before sleeping the connection):
> > + *
> > + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> > + * The second argument is a boolean return value. True indicates that there
> > + * are pending messages on the ring (i.e., the connection should not be put
> > + * to sleep).
> > + *
> > + * These macros will set the req_event/rsp_event field to trigger a
> > + * notification on the very next message that is enqueued. If you want to
> > + * create batches of work (i.e., only receive a notification after several
> > + * messages have been enqueued) then you will need to create a customised
> > + * version of the FINAL_CHECK macro in your own code, which sets the event
> > + * field appropriately.
> > + */
> > +
> > +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> > + RING_IDX __old = (_r)->sring->req_prod; \
> > + RING_IDX __new = (_r)->req_prod_pvt; \
> > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > + (_r)->sring->req_prod = __new; \
> > + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> > + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> > + (RING_IDX)(__new - __old)); \
> > +} while (0)
> > +
> > +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> > + RING_IDX __old = (_r)->sring->rsp_prod; \
> > + RING_IDX __new = (_r)->rsp_prod_pvt; \
> > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > + (_r)->sring->rsp_prod = __new; \
> > + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> > + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> > + (RING_IDX)(__new - __old)); \
> > +} while (0)
> > +
> > +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > + if (_work_to_do) break; \
> > + (_r)->sring->req_event = (_r)->req_cons + 1; \
> > + xen_mb(); \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > +} while (0)
> > +
> > +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > + if (_work_to_do) break; \
> > + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> > + xen_mb(); \
> > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > +} while (0)
> > +
> > +
> > +/*
> > + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> > + * functions to check if there is data on the ring, and to read and
> > + * write to them.
> > + *
> > + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> > + * does not define the indexes page. As different protocols can have
> > + * extensions to the basic format, this macro allow them to define their
> > + * own struct.
> > + *
> > + * XEN_FLEX_RING_SIZE
> > + * Convenience macro to calculate the size of one of the two rings
> > + * from the overall order.
> > + *
> > + * $NAME_mask
> > + * Function to apply the size mask to an index, to reduce the index
> > + * within the range [0-size].
> > + *
> > + * $NAME_read_packet
> > + * Function to read data from the ring. The amount of data to read is
> > + * specified by the "size" argument.
> > + *
> > + * $NAME_write_packet
> > + * Function to write data to the ring. The amount of data to write is
> > + * specified by the "size" argument.
> > + *
> > + * $NAME_get_ring_ptr
> > + * Convenience function that returns a pointer to read/write to the
> > + * ring at the right location.
> > + *
> > + * $NAME_data_intf
> > + * Indexes page, shared between frontend and backend. It also
> > + * contains the array of grant refs.
> > + *
> > + * $NAME_queued
> > + * Function to calculate how many bytes are currently on the ring,
> > + * ready to be read. It can also be used to calculate how much free
> > + * space is currently on the ring (ring_size - $NAME_queued()).
> > + */
> > +#define XEN_FLEX_RING_SIZE(order) \
> > + (1UL << (order + PAGE_SHIFT - 1))
> > +
> > +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> > +struct name##_data_intf { \
> > + RING_IDX in_cons, in_prod; \
> > + \
> > + uint8_t pad1[56]; \
> > + \
> > + RING_IDX out_cons, out_prod; \
> > + \
> > + uint8_t pad2[56]; \
> > + \
> > + RING_IDX ring_order; \
> > + grant_ref_t ref[]; \
> > +}; \
> > +DEFINE_XEN_FLEX_RING(name);
> > +
> > +#define DEFINE_XEN_FLEX_RING(name) \
> > +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> > +{ \
> > + return (idx & (ring_size - 1)); \
> > +} \
> > + \
> > +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> > +{ \
> > + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> > +} \
> > + \
> > +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> > + RING_IDX idx, \
> > + RING_IDX ring_order) \
> > +{ \
> > + return buf + name##_mask_order(idx, ring_order); \
> > +} \
> > + \
> > +static inline void name##_read_packet(const unsigned char *buf, \
> > + RING_IDX masked_prod, RING_IDX *masked_cons, \
> > + RING_IDX ring_size, void *opaque, size_t size) { \
> > + if (*masked_cons < masked_prod || \
> > + size <= ring_size - *masked_cons) { \
> > + memcpy(opaque, buf + *masked_cons, size); \
> > + } else { \
> > + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> > + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> > + size - (ring_size - *masked_cons)); \
> > + } \
> > + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> > +} \
> > + \
> > +static inline void name##_write_packet(unsigned char *buf, \
> > + RING_IDX *masked_prod, RING_IDX masked_cons, \
> > + RING_IDX ring_size, const void *opaque, size_t size) { \
> > + if (*masked_prod < masked_cons || \
> > + size <= ring_size - *masked_prod) { \
> > + memcpy(buf + *masked_prod, opaque, size); \
> > + } else { \
> > + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> > + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> > + size - (ring_size - *masked_prod)); \
> > + } \
> > + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> > +} \
> > + \
> > +struct name##_data { \
> > + unsigned char *in; /* half of the allocation */ \
> > + unsigned char *out; /* half of the allocation */ \
> > +}; \
> > + \
> > + \
> > +static inline RING_IDX name##_queued(RING_IDX prod, \
> > + RING_IDX cons, RING_IDX ring_size) \
> > +{ \
> > + RING_IDX size; \
> > + \
> > + if (prod == cons) \
> > + return 0; \
> > + \
> > + prod = name##_mask(prod, ring_size); \
> > + cons = name##_mask(cons, ring_size); \
> > + \
> > + if (prod == cons) \
> > + return ring_size; \
> > + \
> > + if (prod > cons) \
> > + size = prod - cons; \
> > + else \
> > + size = ring_size - (cons - prod); \
> > + return size; \
> > +};
> > +
> > +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> > +
> > +/*
> > + * Local variables:
> > + * mode: C
> > + * c-file-style: "BSD"
> > + * c-basic-offset: 4
> > + * tab-width: 4
> > + * indent-tabs-mode: nil
> > + * End:
> > + */
>
>
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 2/9] xen: import ring.h from xen
2017-03-15 18:36 ` Stefano Stabellini
@ 2017-03-15 19:00 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 19:00 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini, jgross
[-- Attachment #1: Type: text/plain, Size: 30341 bytes --]
On Wed, 15 Mar 2017 11:36:12 -0700 (PDT)
Stefano Stabellini <sstabellini@kernel.org> wrote:
> On Wed, 15 Mar 2017, Greg Kurz wrote:
> > On Mon, 13 Mar 2017 16:55:53 -0700
> > Stefano Stabellini <sstabellini@kernel.org> wrote:
> >
> > > Do not use the ring.h header installed on the system. Instead, import
> > > the header into the QEMU codebase. This avoids problems when QEMU is
> > > built against a Xen version too old to provide all the ring macros.
> > >
> >
> > What kind of problems ?
>
> The FLEX macros are only available in Xen 4.9+ (still unreleased).
> However, aside from these macros, the Xen 9pfs frontends and backends
> could work fine on any Xen releases. In fact, the Xen public/io headers
> are only provided as reference.
>
Ok.
>
> > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > CC: anthony.perard@citrix.com
> > > CC: jgross@suse.com
> > > ---
> > > NB: The new macros have not been committed to Xen yet. Do not apply this
> > > patch until they do.
> >
> > Why ? Does this break compat with older Xen ?
>
> No, it does not break compatibility. But I think it is a good idea to
> commit the header to QEMU only after the corresponding Xen header has
> been accepted. I don't want the two to diverge.
>
Fair enough but this will put the entire patchset on hold then. When Xen 4.9
is supposed to be released ?
>
> > > ---
> > > ---
> > > hw/block/xen_blkif.h | 2 +-
> > > hw/usb/xen-usb.c | 2 +-
> > > include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> > > 3 files changed, 457 insertions(+), 2 deletions(-)
> > > create mode 100644 include/hw/xen/io/ring.h
> > >
> > > diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> > > index 3300b6f..3e6e1ea 100644
> > > --- a/hw/block/xen_blkif.h
> > > +++ b/hw/block/xen_blkif.h
> > > @@ -1,7 +1,7 @@
> > > #ifndef XEN_BLKIF_H
> > > #define XEN_BLKIF_H
> > >
> > > -#include <xen/io/ring.h>
> > > +#include "hw/xen/io/ring.h"
> > > #include <xen/io/blkif.h>
> > > #include <xen/io/protocols.h>
> > >
> > > diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> > > index 8e676e6..370b3d9 100644
> > > --- a/hw/usb/xen-usb.c
> > > +++ b/hw/usb/xen-usb.c
> > > @@ -33,7 +33,7 @@
> > > #include "qapi/qmp/qint.h"
> > > #include "qapi/qmp/qstring.h"
> > >
> > > -#include <xen/io/ring.h>
> > > +#include "hw/xen/io/ring.h"
> > > #include <xen/io/usbif.h>
> > >
> > > /*
> > > diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> > > new file mode 100644
> > > index 0000000..cf01fc3
> > > --- /dev/null
> > > +++ b/include/hw/xen/io/ring.h
> > > @@ -0,0 +1,455 @@
> > > +/******************************************************************************
> > > + * ring.h
> > > + *
> > > + * Shared producer-consumer ring macros.
> > > + *
> > > + * Permission is hereby granted, free of charge, to any person obtaining a copy
> > > + * of this software and associated documentation files (the "Software"), to
> > > + * deal in the Software without restriction, including without limitation the
> > > + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> > > + * sell copies of the Software, and to permit persons to whom the Software is
> > > + * furnished to do so, subject to the following conditions:
> > > + *
> > > + * The above copyright notice and this permission notice shall be included in
> > > + * all copies or substantial portions of the Software.
> > > + *
> > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> > > + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> > > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> > > + * DEALINGS IN THE SOFTWARE.
> > > + *
> > > + * Tim Deegan and Andrew Warfield November 2004.
> > > + */
> > > +
> > > +#ifndef __XEN_PUBLIC_IO_RING_H__
> > > +#define __XEN_PUBLIC_IO_RING_H__
> > > +
> > > +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> > > +#define xen_mb() mb()
> > > +#define xen_rmb() rmb()
> > > +#define xen_wmb() wmb()
> > > +#endif
> > > +
> > > +typedef unsigned int RING_IDX;
> > > +
> > > +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> > > +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> > > +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> > > +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> > > +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> > > +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> > > +
> > > +/*
> > > + * Calculate size of a shared ring, given the total available space for the
> > > + * ring and indexes (_sz), and the name tag of the request/response structure.
> > > + * A ring contains as many entries as will fit, rounded down to the nearest
> > > + * power of two (so we can mask with (size-1) to loop around).
> > > + */
> > > +#define __CONST_RING_SIZE(_s, _sz) \
> > > + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> > > + sizeof(((struct _s##_sring *)0)->ring[0])))
> > > +/*
> > > + * The same for passing in an actual pointer instead of a name tag.
> > > + */
> > > +#define __RING_SIZE(_s, _sz) \
> > > + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> > > +
> > > +/*
> > > + * Macros to make the correct C datatypes for a new kind of ring.
> > > + *
> > > + * To make a new ring datatype, you need to have two message structures,
> > > + * let's say request_t, and response_t already defined.
> > > + *
> > > + * In a header where you want the ring datatype declared, you then do:
> > > + *
> > > + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> > > + *
> > > + * These expand out to give you a set of types, as you can see below.
> > > + * The most important of these are:
> > > + *
> > > + * mytag_sring_t - The shared ring.
> > > + * mytag_front_ring_t - The 'front' half of the ring.
> > > + * mytag_back_ring_t - The 'back' half of the ring.
> > > + *
> > > + * To initialize a ring in your code you need to know the location and size
> > > + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> > > + * the front half:
> > > + *
> > > + * mytag_front_ring_t front_ring;
> > > + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> > > + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > + *
> > > + * Initializing the back follows similarly (note that only the front
> > > + * initializes the shared ring):
> > > + *
> > > + * mytag_back_ring_t back_ring;
> > > + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > + */
> > > +
> > > +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> > > + \
> > > +/* Shared ring entry */ \
> > > +union __name##_sring_entry { \
> > > + __req_t req; \
> > > + __rsp_t rsp; \
> > > +}; \
> > > + \
> > > +/* Shared ring page */ \
> > > +struct __name##_sring { \
> > > + RING_IDX req_prod, req_event; \
> > > + RING_IDX rsp_prod, rsp_event; \
> > > + union { \
> > > + struct { \
> > > + uint8_t smartpoll_active; \
> > > + } netif; \
> > > + struct { \
> > > + uint8_t msg; \
> > > + } tapif_user; \
> > > + uint8_t pvt_pad[4]; \
> > > + } pvt; \
> > > + uint8_t __pad[44]; \
> > > + union __name##_sring_entry ring[1]; /* variable-length */ \
> > > +}; \
> > > + \
> > > +/* "Front" end's private variables */ \
> > > +struct __name##_front_ring { \
> > > + RING_IDX req_prod_pvt; \
> > > + RING_IDX rsp_cons; \
> > > + unsigned int nr_ents; \
> > > + struct __name##_sring *sring; \
> > > +}; \
> > > + \
> > > +/* "Back" end's private variables */ \
> > > +struct __name##_back_ring { \
> > > + RING_IDX rsp_prod_pvt; \
> > > + RING_IDX req_cons; \
> > > + unsigned int nr_ents; \
> > > + struct __name##_sring *sring; \
> > > +}; \
> > > + \
> > > +/* Syntactic sugar */ \
> > > +typedef struct __name##_sring __name##_sring_t; \
> > > +typedef struct __name##_front_ring __name##_front_ring_t; \
> > > +typedef struct __name##_back_ring __name##_back_ring_t
> > > +
> > > +/*
> > > + * Macros for manipulating rings.
> > > + *
> > > + * FRONT_RING_whatever works on the "front end" of a ring: here
> > > + * requests are pushed on to the ring and responses taken off it.
> > > + *
> > > + * BACK_RING_whatever works on the "back end" of a ring: here
> > > + * requests are taken off the ring and responses put on.
> > > + *
> > > + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> > > + * This is OK in 1-for-1 request-response situations where the
> > > + * requestor (front end) never has more than RING_SIZE()-1
> > > + * outstanding requests.
> > > + */
> > > +
> > > +/* Initialising empty rings */
> > > +#define SHARED_RING_INIT(_s) do { \
> > > + (_s)->req_prod = (_s)->rsp_prod = 0; \
> > > + (_s)->req_event = (_s)->rsp_event = 1; \
> > > + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> > > + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> > > +} while(0)
> > > +
> > > +#define FRONT_RING_INIT(_r, _s, __size) do { \
> > > + (_r)->req_prod_pvt = 0; \
> > > + (_r)->rsp_cons = 0; \
> > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > + (_r)->sring = (_s); \
> > > +} while (0)
> > > +
> > > +#define BACK_RING_INIT(_r, _s, __size) do { \
> > > + (_r)->rsp_prod_pvt = 0; \
> > > + (_r)->req_cons = 0; \
> > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > + (_r)->sring = (_s); \
> > > +} while (0)
> > > +
> > > +/* How big is this ring? */
> > > +#define RING_SIZE(_r) \
> > > + ((_r)->nr_ents)
> > > +
> > > +/* Number of free requests (for use on front side only). */
> > > +#define RING_FREE_REQUESTS(_r) \
> > > + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> > > +
> > > +/* Test if there is an empty slot available on the front ring.
> > > + * (This is only meaningful from the front. )
> > > + */
> > > +#define RING_FULL(_r) \
> > > + (RING_FREE_REQUESTS(_r) == 0)
> > > +
> > > +/* Test if there are outstanding messages to be processed on a ring. */
> > > +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> > > + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> > > +
> > > +#ifdef __GNUC__
> > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> > > + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> > > + unsigned int rsp = RING_SIZE(_r) - \
> > > + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> > > + req < rsp ? req : rsp; \
> > > +})
> > > +#else
> > > +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> > > + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> > > + ((_r)->sring->req_prod - (_r)->req_cons) : \
> > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> > > +#endif
> > > +
> > > +/* Direct access to individual ring elements, by index. */
> > > +#define RING_GET_REQUEST(_r, _idx) \
> > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> > > +
> > > +/*
> > > + * Get a local copy of a request.
> > > + *
> > > + * Use this in preference to RING_GET_REQUEST() so all processing is
> > > + * done on a local copy that cannot be modified by the other end.
> > > + *
> > > + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> > > + * to be ineffective where _req is a struct which consists of only bitfields.
> > > + */
> > > +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> > > + /* Use volatile to force the copy into _req. */ \
> > > + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> > > +} while (0)
> > > +
> > > +#define RING_GET_RESPONSE(_r, _idx) \
> > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> > > +
> > > +/* Loop termination condition: Would the specified index overflow the ring? */
> > > +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> > > + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> > > +
> > > +/* Ill-behaved frontend determination: Can there be this many requests? */
> > > +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> > > + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> > > +
> > > +#define RING_PUSH_REQUESTS(_r) do { \
> > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> > > +} while (0)
> > > +
> > > +#define RING_PUSH_RESPONSES(_r) do { \
> > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> > > +} while (0)
> > > +
> > > +/*
> > > + * Notification hold-off (req_event and rsp_event):
> > > + *
> > > + * When queueing requests or responses on a shared ring, it may not always be
> > > + * necessary to notify the remote end. For example, if requests are in flight
> > > + * in a backend, the front may be able to queue further requests without
> > > + * notifying the back (if the back checks for new requests when it queues
> > > + * responses).
> > > + *
> > > + * When enqueuing requests or responses:
> > > + *
> > > + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> > > + * is a boolean return value. True indicates that the receiver requires an
> > > + * asynchronous notification.
> > > + *
> > > + * After dequeuing requests or responses (before sleeping the connection):
> > > + *
> > > + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> > > + * The second argument is a boolean return value. True indicates that there
> > > + * are pending messages on the ring (i.e., the connection should not be put
> > > + * to sleep).
> > > + *
> > > + * These macros will set the req_event/rsp_event field to trigger a
> > > + * notification on the very next message that is enqueued. If you want to
> > > + * create batches of work (i.e., only receive a notification after several
> > > + * messages have been enqueued) then you will need to create a customised
> > > + * version of the FINAL_CHECK macro in your own code, which sets the event
> > > + * field appropriately.
> > > + */
> > > +
> > > +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > + RING_IDX __old = (_r)->sring->req_prod; \
> > > + RING_IDX __new = (_r)->req_prod_pvt; \
> > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > + (_r)->sring->req_prod = __new; \
> > > + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> > > + (RING_IDX)(__new - __old)); \
> > > +} while (0)
> > > +
> > > +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > + RING_IDX __old = (_r)->sring->rsp_prod; \
> > > + RING_IDX __new = (_r)->rsp_prod_pvt; \
> > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > + (_r)->sring->rsp_prod = __new; \
> > > + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> > > + (RING_IDX)(__new - __old)); \
> > > +} while (0)
> > > +
> > > +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > + if (_work_to_do) break; \
> > > + (_r)->sring->req_event = (_r)->req_cons + 1; \
> > > + xen_mb(); \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > +} while (0)
> > > +
> > > +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > + if (_work_to_do) break; \
> > > + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> > > + xen_mb(); \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > +} while (0)
> > > +
> > > +
> > > +/*
> > > + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> > > + * functions to check if there is data on the ring, and to read and
> > > + * write to them.
> > > + *
> > > + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> > > + * does not define the indexes page. As different protocols can have
> > > + * extensions to the basic format, this macro allow them to define their
> > > + * own struct.
> > > + *
> > > + * XEN_FLEX_RING_SIZE
> > > + * Convenience macro to calculate the size of one of the two rings
> > > + * from the overall order.
> > > + *
> > > + * $NAME_mask
> > > + * Function to apply the size mask to an index, to reduce the index
> > > + * within the range [0-size].
> > > + *
> > > + * $NAME_read_packet
> > > + * Function to read data from the ring. The amount of data to read is
> > > + * specified by the "size" argument.
> > > + *
> > > + * $NAME_write_packet
> > > + * Function to write data to the ring. The amount of data to write is
> > > + * specified by the "size" argument.
> > > + *
> > > + * $NAME_get_ring_ptr
> > > + * Convenience function that returns a pointer to read/write to the
> > > + * ring at the right location.
> > > + *
> > > + * $NAME_data_intf
> > > + * Indexes page, shared between frontend and backend. It also
> > > + * contains the array of grant refs.
> > > + *
> > > + * $NAME_queued
> > > + * Function to calculate how many bytes are currently on the ring,
> > > + * ready to be read. It can also be used to calculate how much free
> > > + * space is currently on the ring (ring_size - $NAME_queued()).
> > > + */
> > > +#define XEN_FLEX_RING_SIZE(order) \
> > > + (1UL << (order + PAGE_SHIFT - 1))
> > > +
> > > +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> > > +struct name##_data_intf { \
> > > + RING_IDX in_cons, in_prod; \
> > > + \
> > > + uint8_t pad1[56]; \
> > > + \
> > > + RING_IDX out_cons, out_prod; \
> > > + \
> > > + uint8_t pad2[56]; \
> > > + \
> > > + RING_IDX ring_order; \
> > > + grant_ref_t ref[]; \
> > > +}; \
> > > +DEFINE_XEN_FLEX_RING(name);
> > > +
> > > +#define DEFINE_XEN_FLEX_RING(name) \
> > > +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> > > +{ \
> > > + return (idx & (ring_size - 1)); \
> > > +} \
> > > + \
> > > +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> > > +{ \
> > > + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> > > +} \
> > > + \
> > > +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> > > + RING_IDX idx, \
> > > + RING_IDX ring_order) \
> > > +{ \
> > > + return buf + name##_mask_order(idx, ring_order); \
> > > +} \
> > > + \
> > > +static inline void name##_read_packet(const unsigned char *buf, \
> > > + RING_IDX masked_prod, RING_IDX *masked_cons, \
> > > + RING_IDX ring_size, void *opaque, size_t size) { \
> > > + if (*masked_cons < masked_prod || \
> > > + size <= ring_size - *masked_cons) { \
> > > + memcpy(opaque, buf + *masked_cons, size); \
> > > + } else { \
> > > + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> > > + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> > > + size - (ring_size - *masked_cons)); \
> > > + } \
> > > + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> > > +} \
> > > + \
> > > +static inline void name##_write_packet(unsigned char *buf, \
> > > + RING_IDX *masked_prod, RING_IDX masked_cons, \
> > > + RING_IDX ring_size, const void *opaque, size_t size) { \
> > > + if (*masked_prod < masked_cons || \
> > > + size <= ring_size - *masked_prod) { \
> > > + memcpy(buf + *masked_prod, opaque, size); \
> > > + } else { \
> > > + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> > > + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> > > + size - (ring_size - *masked_prod)); \
> > > + } \
> > > + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> > > +} \
> > > + \
> > > +struct name##_data { \
> > > + unsigned char *in; /* half of the allocation */ \
> > > + unsigned char *out; /* half of the allocation */ \
> > > +}; \
> > > + \
> > > + \
> > > +static inline RING_IDX name##_queued(RING_IDX prod, \
> > > + RING_IDX cons, RING_IDX ring_size) \
> > > +{ \
> > > + RING_IDX size; \
> > > + \
> > > + if (prod == cons) \
> > > + return 0; \
> > > + \
> > > + prod = name##_mask(prod, ring_size); \
> > > + cons = name##_mask(cons, ring_size); \
> > > + \
> > > + if (prod == cons) \
> > > + return ring_size; \
> > > + \
> > > + if (prod > cons) \
> > > + size = prod - cons; \
> > > + else \
> > > + size = ring_size - (cons - prod); \
> > > + return size; \
> > > +};
> > > +
> > > +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> > > +
> > > +/*
> > > + * Local variables:
> > > + * mode: C
> > > + * c-file-style: "BSD"
> > > + * c-basic-offset: 4
> > > + * tab-width: 4
> > > + * indent-tabs-mode: nil
> > > + * End:
> > > + */
> >
> >
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 2/9] xen: import ring.h from xen
@ 2017-03-15 19:00 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 19:00 UTC (permalink / raw)
To: Stefano Stabellini
Cc: anthony.perard, xen-devel, Stefano Stabellini, qemu-devel, jgross
[-- Attachment #1.1: Type: text/plain, Size: 30341 bytes --]
On Wed, 15 Mar 2017 11:36:12 -0700 (PDT)
Stefano Stabellini <sstabellini@kernel.org> wrote:
> On Wed, 15 Mar 2017, Greg Kurz wrote:
> > On Mon, 13 Mar 2017 16:55:53 -0700
> > Stefano Stabellini <sstabellini@kernel.org> wrote:
> >
> > > Do not use the ring.h header installed on the system. Instead, import
> > > the header into the QEMU codebase. This avoids problems when QEMU is
> > > built against a Xen version too old to provide all the ring macros.
> > >
> >
> > What kind of problems ?
>
> The FLEX macros are only available in Xen 4.9+ (still unreleased).
> However, aside from these macros, the Xen 9pfs frontends and backends
> could work fine on any Xen releases. In fact, the Xen public/io headers
> are only provided as reference.
>
Ok.
>
> > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > CC: anthony.perard@citrix.com
> > > CC: jgross@suse.com
> > > ---
> > > NB: The new macros have not been committed to Xen yet. Do not apply this
> > > patch until they do.
> >
> > Why ? Does this break compat with older Xen ?
>
> No, it does not break compatibility. But I think it is a good idea to
> commit the header to QEMU only after the corresponding Xen header has
> been accepted. I don't want the two to diverge.
>
Fair enough but this will put the entire patchset on hold then. When Xen 4.9
is supposed to be released ?
>
> > > ---
> > > ---
> > > hw/block/xen_blkif.h | 2 +-
> > > hw/usb/xen-usb.c | 2 +-
> > > include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> > > 3 files changed, 457 insertions(+), 2 deletions(-)
> > > create mode 100644 include/hw/xen/io/ring.h
> > >
> > > diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> > > index 3300b6f..3e6e1ea 100644
> > > --- a/hw/block/xen_blkif.h
> > > +++ b/hw/block/xen_blkif.h
> > > @@ -1,7 +1,7 @@
> > > #ifndef XEN_BLKIF_H
> > > #define XEN_BLKIF_H
> > >
> > > -#include <xen/io/ring.h>
> > > +#include "hw/xen/io/ring.h"
> > > #include <xen/io/blkif.h>
> > > #include <xen/io/protocols.h>
> > >
> > > diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> > > index 8e676e6..370b3d9 100644
> > > --- a/hw/usb/xen-usb.c
> > > +++ b/hw/usb/xen-usb.c
> > > @@ -33,7 +33,7 @@
> > > #include "qapi/qmp/qint.h"
> > > #include "qapi/qmp/qstring.h"
> > >
> > > -#include <xen/io/ring.h>
> > > +#include "hw/xen/io/ring.h"
> > > #include <xen/io/usbif.h>
> > >
> > > /*
> > > diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> > > new file mode 100644
> > > index 0000000..cf01fc3
> > > --- /dev/null
> > > +++ b/include/hw/xen/io/ring.h
> > > @@ -0,0 +1,455 @@
> > > +/******************************************************************************
> > > + * ring.h
> > > + *
> > > + * Shared producer-consumer ring macros.
> > > + *
> > > + * Permission is hereby granted, free of charge, to any person obtaining a copy
> > > + * of this software and associated documentation files (the "Software"), to
> > > + * deal in the Software without restriction, including without limitation the
> > > + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> > > + * sell copies of the Software, and to permit persons to whom the Software is
> > > + * furnished to do so, subject to the following conditions:
> > > + *
> > > + * The above copyright notice and this permission notice shall be included in
> > > + * all copies or substantial portions of the Software.
> > > + *
> > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> > > + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> > > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> > > + * DEALINGS IN THE SOFTWARE.
> > > + *
> > > + * Tim Deegan and Andrew Warfield November 2004.
> > > + */
> > > +
> > > +#ifndef __XEN_PUBLIC_IO_RING_H__
> > > +#define __XEN_PUBLIC_IO_RING_H__
> > > +
> > > +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> > > +#define xen_mb() mb()
> > > +#define xen_rmb() rmb()
> > > +#define xen_wmb() wmb()
> > > +#endif
> > > +
> > > +typedef unsigned int RING_IDX;
> > > +
> > > +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> > > +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> > > +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> > > +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> > > +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> > > +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> > > +
> > > +/*
> > > + * Calculate size of a shared ring, given the total available space for the
> > > + * ring and indexes (_sz), and the name tag of the request/response structure.
> > > + * A ring contains as many entries as will fit, rounded down to the nearest
> > > + * power of two (so we can mask with (size-1) to loop around).
> > > + */
> > > +#define __CONST_RING_SIZE(_s, _sz) \
> > > + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> > > + sizeof(((struct _s##_sring *)0)->ring[0])))
> > > +/*
> > > + * The same for passing in an actual pointer instead of a name tag.
> > > + */
> > > +#define __RING_SIZE(_s, _sz) \
> > > + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> > > +
> > > +/*
> > > + * Macros to make the correct C datatypes for a new kind of ring.
> > > + *
> > > + * To make a new ring datatype, you need to have two message structures,
> > > + * let's say request_t, and response_t already defined.
> > > + *
> > > + * In a header where you want the ring datatype declared, you then do:
> > > + *
> > > + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> > > + *
> > > + * These expand out to give you a set of types, as you can see below.
> > > + * The most important of these are:
> > > + *
> > > + * mytag_sring_t - The shared ring.
> > > + * mytag_front_ring_t - The 'front' half of the ring.
> > > + * mytag_back_ring_t - The 'back' half of the ring.
> > > + *
> > > + * To initialize a ring in your code you need to know the location and size
> > > + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> > > + * the front half:
> > > + *
> > > + * mytag_front_ring_t front_ring;
> > > + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> > > + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > + *
> > > + * Initializing the back follows similarly (note that only the front
> > > + * initializes the shared ring):
> > > + *
> > > + * mytag_back_ring_t back_ring;
> > > + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > + */
> > > +
> > > +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> > > + \
> > > +/* Shared ring entry */ \
> > > +union __name##_sring_entry { \
> > > + __req_t req; \
> > > + __rsp_t rsp; \
> > > +}; \
> > > + \
> > > +/* Shared ring page */ \
> > > +struct __name##_sring { \
> > > + RING_IDX req_prod, req_event; \
> > > + RING_IDX rsp_prod, rsp_event; \
> > > + union { \
> > > + struct { \
> > > + uint8_t smartpoll_active; \
> > > + } netif; \
> > > + struct { \
> > > + uint8_t msg; \
> > > + } tapif_user; \
> > > + uint8_t pvt_pad[4]; \
> > > + } pvt; \
> > > + uint8_t __pad[44]; \
> > > + union __name##_sring_entry ring[1]; /* variable-length */ \
> > > +}; \
> > > + \
> > > +/* "Front" end's private variables */ \
> > > +struct __name##_front_ring { \
> > > + RING_IDX req_prod_pvt; \
> > > + RING_IDX rsp_cons; \
> > > + unsigned int nr_ents; \
> > > + struct __name##_sring *sring; \
> > > +}; \
> > > + \
> > > +/* "Back" end's private variables */ \
> > > +struct __name##_back_ring { \
> > > + RING_IDX rsp_prod_pvt; \
> > > + RING_IDX req_cons; \
> > > + unsigned int nr_ents; \
> > > + struct __name##_sring *sring; \
> > > +}; \
> > > + \
> > > +/* Syntactic sugar */ \
> > > +typedef struct __name##_sring __name##_sring_t; \
> > > +typedef struct __name##_front_ring __name##_front_ring_t; \
> > > +typedef struct __name##_back_ring __name##_back_ring_t
> > > +
> > > +/*
> > > + * Macros for manipulating rings.
> > > + *
> > > + * FRONT_RING_whatever works on the "front end" of a ring: here
> > > + * requests are pushed on to the ring and responses taken off it.
> > > + *
> > > + * BACK_RING_whatever works on the "back end" of a ring: here
> > > + * requests are taken off the ring and responses put on.
> > > + *
> > > + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> > > + * This is OK in 1-for-1 request-response situations where the
> > > + * requestor (front end) never has more than RING_SIZE()-1
> > > + * outstanding requests.
> > > + */
> > > +
> > > +/* Initialising empty rings */
> > > +#define SHARED_RING_INIT(_s) do { \
> > > + (_s)->req_prod = (_s)->rsp_prod = 0; \
> > > + (_s)->req_event = (_s)->rsp_event = 1; \
> > > + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> > > + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> > > +} while(0)
> > > +
> > > +#define FRONT_RING_INIT(_r, _s, __size) do { \
> > > + (_r)->req_prod_pvt = 0; \
> > > + (_r)->rsp_cons = 0; \
> > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > + (_r)->sring = (_s); \
> > > +} while (0)
> > > +
> > > +#define BACK_RING_INIT(_r, _s, __size) do { \
> > > + (_r)->rsp_prod_pvt = 0; \
> > > + (_r)->req_cons = 0; \
> > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > + (_r)->sring = (_s); \
> > > +} while (0)
> > > +
> > > +/* How big is this ring? */
> > > +#define RING_SIZE(_r) \
> > > + ((_r)->nr_ents)
> > > +
> > > +/* Number of free requests (for use on front side only). */
> > > +#define RING_FREE_REQUESTS(_r) \
> > > + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> > > +
> > > +/* Test if there is an empty slot available on the front ring.
> > > + * (This is only meaningful from the front. )
> > > + */
> > > +#define RING_FULL(_r) \
> > > + (RING_FREE_REQUESTS(_r) == 0)
> > > +
> > > +/* Test if there are outstanding messages to be processed on a ring. */
> > > +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> > > + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> > > +
> > > +#ifdef __GNUC__
> > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> > > + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> > > + unsigned int rsp = RING_SIZE(_r) - \
> > > + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> > > + req < rsp ? req : rsp; \
> > > +})
> > > +#else
> > > +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> > > + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> > > + ((_r)->sring->req_prod - (_r)->req_cons) : \
> > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> > > +#endif
> > > +
> > > +/* Direct access to individual ring elements, by index. */
> > > +#define RING_GET_REQUEST(_r, _idx) \
> > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> > > +
> > > +/*
> > > + * Get a local copy of a request.
> > > + *
> > > + * Use this in preference to RING_GET_REQUEST() so all processing is
> > > + * done on a local copy that cannot be modified by the other end.
> > > + *
> > > + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> > > + * to be ineffective where _req is a struct which consists of only bitfields.
> > > + */
> > > +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> > > + /* Use volatile to force the copy into _req. */ \
> > > + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> > > +} while (0)
> > > +
> > > +#define RING_GET_RESPONSE(_r, _idx) \
> > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> > > +
> > > +/* Loop termination condition: Would the specified index overflow the ring? */
> > > +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> > > + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> > > +
> > > +/* Ill-behaved frontend determination: Can there be this many requests? */
> > > +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> > > + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> > > +
> > > +#define RING_PUSH_REQUESTS(_r) do { \
> > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> > > +} while (0)
> > > +
> > > +#define RING_PUSH_RESPONSES(_r) do { \
> > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> > > +} while (0)
> > > +
> > > +/*
> > > + * Notification hold-off (req_event and rsp_event):
> > > + *
> > > + * When queueing requests or responses on a shared ring, it may not always be
> > > + * necessary to notify the remote end. For example, if requests are in flight
> > > + * in a backend, the front may be able to queue further requests without
> > > + * notifying the back (if the back checks for new requests when it queues
> > > + * responses).
> > > + *
> > > + * When enqueuing requests or responses:
> > > + *
> > > + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> > > + * is a boolean return value. True indicates that the receiver requires an
> > > + * asynchronous notification.
> > > + *
> > > + * After dequeuing requests or responses (before sleeping the connection):
> > > + *
> > > + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> > > + * The second argument is a boolean return value. True indicates that there
> > > + * are pending messages on the ring (i.e., the connection should not be put
> > > + * to sleep).
> > > + *
> > > + * These macros will set the req_event/rsp_event field to trigger a
> > > + * notification on the very next message that is enqueued. If you want to
> > > + * create batches of work (i.e., only receive a notification after several
> > > + * messages have been enqueued) then you will need to create a customised
> > > + * version of the FINAL_CHECK macro in your own code, which sets the event
> > > + * field appropriately.
> > > + */
> > > +
> > > +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > + RING_IDX __old = (_r)->sring->req_prod; \
> > > + RING_IDX __new = (_r)->req_prod_pvt; \
> > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > + (_r)->sring->req_prod = __new; \
> > > + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> > > + (RING_IDX)(__new - __old)); \
> > > +} while (0)
> > > +
> > > +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > + RING_IDX __old = (_r)->sring->rsp_prod; \
> > > + RING_IDX __new = (_r)->rsp_prod_pvt; \
> > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > + (_r)->sring->rsp_prod = __new; \
> > > + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> > > + (RING_IDX)(__new - __old)); \
> > > +} while (0)
> > > +
> > > +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > + if (_work_to_do) break; \
> > > + (_r)->sring->req_event = (_r)->req_cons + 1; \
> > > + xen_mb(); \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > +} while (0)
> > > +
> > > +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > + if (_work_to_do) break; \
> > > + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> > > + xen_mb(); \
> > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > +} while (0)
> > > +
> > > +
> > > +/*
> > > + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> > > + * functions to check if there is data on the ring, and to read and
> > > + * write to them.
> > > + *
> > > + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> > > + * does not define the indexes page. As different protocols can have
> > > + * extensions to the basic format, this macro allow them to define their
> > > + * own struct.
> > > + *
> > > + * XEN_FLEX_RING_SIZE
> > > + * Convenience macro to calculate the size of one of the two rings
> > > + * from the overall order.
> > > + *
> > > + * $NAME_mask
> > > + * Function to apply the size mask to an index, to reduce the index
> > > + * within the range [0-size].
> > > + *
> > > + * $NAME_read_packet
> > > + * Function to read data from the ring. The amount of data to read is
> > > + * specified by the "size" argument.
> > > + *
> > > + * $NAME_write_packet
> > > + * Function to write data to the ring. The amount of data to write is
> > > + * specified by the "size" argument.
> > > + *
> > > + * $NAME_get_ring_ptr
> > > + * Convenience function that returns a pointer to read/write to the
> > > + * ring at the right location.
> > > + *
> > > + * $NAME_data_intf
> > > + * Indexes page, shared between frontend and backend. It also
> > > + * contains the array of grant refs.
> > > + *
> > > + * $NAME_queued
> > > + * Function to calculate how many bytes are currently on the ring,
> > > + * ready to be read. It can also be used to calculate how much free
> > > + * space is currently on the ring (ring_size - $NAME_queued()).
> > > + */
> > > +#define XEN_FLEX_RING_SIZE(order) \
> > > + (1UL << (order + PAGE_SHIFT - 1))
> > > +
> > > +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> > > +struct name##_data_intf { \
> > > + RING_IDX in_cons, in_prod; \
> > > + \
> > > + uint8_t pad1[56]; \
> > > + \
> > > + RING_IDX out_cons, out_prod; \
> > > + \
> > > + uint8_t pad2[56]; \
> > > + \
> > > + RING_IDX ring_order; \
> > > + grant_ref_t ref[]; \
> > > +}; \
> > > +DEFINE_XEN_FLEX_RING(name);
> > > +
> > > +#define DEFINE_XEN_FLEX_RING(name) \
> > > +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> > > +{ \
> > > + return (idx & (ring_size - 1)); \
> > > +} \
> > > + \
> > > +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> > > +{ \
> > > + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> > > +} \
> > > + \
> > > +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> > > + RING_IDX idx, \
> > > + RING_IDX ring_order) \
> > > +{ \
> > > + return buf + name##_mask_order(idx, ring_order); \
> > > +} \
> > > + \
> > > +static inline void name##_read_packet(const unsigned char *buf, \
> > > + RING_IDX masked_prod, RING_IDX *masked_cons, \
> > > + RING_IDX ring_size, void *opaque, size_t size) { \
> > > + if (*masked_cons < masked_prod || \
> > > + size <= ring_size - *masked_cons) { \
> > > + memcpy(opaque, buf + *masked_cons, size); \
> > > + } else { \
> > > + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> > > + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> > > + size - (ring_size - *masked_cons)); \
> > > + } \
> > > + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> > > +} \
> > > + \
> > > +static inline void name##_write_packet(unsigned char *buf, \
> > > + RING_IDX *masked_prod, RING_IDX masked_cons, \
> > > + RING_IDX ring_size, const void *opaque, size_t size) { \
> > > + if (*masked_prod < masked_cons || \
> > > + size <= ring_size - *masked_prod) { \
> > > + memcpy(buf + *masked_prod, opaque, size); \
> > > + } else { \
> > > + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> > > + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> > > + size - (ring_size - *masked_prod)); \
> > > + } \
> > > + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> > > +} \
> > > + \
> > > +struct name##_data { \
> > > + unsigned char *in; /* half of the allocation */ \
> > > + unsigned char *out; /* half of the allocation */ \
> > > +}; \
> > > + \
> > > + \
> > > +static inline RING_IDX name##_queued(RING_IDX prod, \
> > > + RING_IDX cons, RING_IDX ring_size) \
> > > +{ \
> > > + RING_IDX size; \
> > > + \
> > > + if (prod == cons) \
> > > + return 0; \
> > > + \
> > > + prod = name##_mask(prod, ring_size); \
> > > + cons = name##_mask(cons, ring_size); \
> > > + \
> > > + if (prod == cons) \
> > > + return ring_size; \
> > > + \
> > > + if (prod > cons) \
> > > + size = prod - cons; \
> > > + else \
> > > + size = ring_size - (cons - prod); \
> > > + return size; \
> > > +};
> > > +
> > > +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> > > +
> > > +/*
> > > + * Local variables:
> > > + * mode: C
> > > + * c-file-style: "BSD"
> > > + * c-basic-offset: 4
> > > + * tab-width: 4
> > > + * indent-tabs-mode: nil
> > > + * End:
> > > + */
> >
> >
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 2/9] xen: import ring.h from xen
2017-03-15 19:00 ` Greg Kurz
@ 2017-03-15 19:04 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 19:04 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard,
Stefano Stabellini, jgross
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Wed, 15 Mar 2017 11:36:12 -0700 (PDT)
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > On Wed, 15 Mar 2017, Greg Kurz wrote:
> > > On Mon, 13 Mar 2017 16:55:53 -0700
> > > Stefano Stabellini <sstabellini@kernel.org> wrote:
> > >
> > > > Do not use the ring.h header installed on the system. Instead, import
> > > > the header into the QEMU codebase. This avoids problems when QEMU is
> > > > built against a Xen version too old to provide all the ring macros.
> > > >
> > >
> > > What kind of problems ?
> >
> > The FLEX macros are only available in Xen 4.9+ (still unreleased).
> > However, aside from these macros, the Xen 9pfs frontends and backends
> > could work fine on any Xen releases. In fact, the Xen public/io headers
> > are only provided as reference.
> >
>
> Ok.
>
> >
> > > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > > CC: anthony.perard@citrix.com
> > > > CC: jgross@suse.com
> > > > ---
> > > > NB: The new macros have not been committed to Xen yet. Do not apply this
> > > > patch until they do.
> > >
> > > Why ? Does this break compat with older Xen ?
> >
> > No, it does not break compatibility. But I think it is a good idea to
> > commit the header to QEMU only after the corresponding Xen header has
> > been accepted. I don't want the two to diverge.
> >
>
> Fair enough but this will put the entire patchset on hold then. When Xen 4.9
> is supposed to be released ?
In a few months, but I don't think we need to wait until the release,
just for the reviewed-by on the new macros, that should come soon.
> > > > ---
> > > > ---
> > > > hw/block/xen_blkif.h | 2 +-
> > > > hw/usb/xen-usb.c | 2 +-
> > > > include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> > > > 3 files changed, 457 insertions(+), 2 deletions(-)
> > > > create mode 100644 include/hw/xen/io/ring.h
> > > >
> > > > diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> > > > index 3300b6f..3e6e1ea 100644
> > > > --- a/hw/block/xen_blkif.h
> > > > +++ b/hw/block/xen_blkif.h
> > > > @@ -1,7 +1,7 @@
> > > > #ifndef XEN_BLKIF_H
> > > > #define XEN_BLKIF_H
> > > >
> > > > -#include <xen/io/ring.h>
> > > > +#include "hw/xen/io/ring.h"
> > > > #include <xen/io/blkif.h>
> > > > #include <xen/io/protocols.h>
> > > >
> > > > diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> > > > index 8e676e6..370b3d9 100644
> > > > --- a/hw/usb/xen-usb.c
> > > > +++ b/hw/usb/xen-usb.c
> > > > @@ -33,7 +33,7 @@
> > > > #include "qapi/qmp/qint.h"
> > > > #include "qapi/qmp/qstring.h"
> > > >
> > > > -#include <xen/io/ring.h>
> > > > +#include "hw/xen/io/ring.h"
> > > > #include <xen/io/usbif.h>
> > > >
> > > > /*
> > > > diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> > > > new file mode 100644
> > > > index 0000000..cf01fc3
> > > > --- /dev/null
> > > > +++ b/include/hw/xen/io/ring.h
> > > > @@ -0,0 +1,455 @@
> > > > +/******************************************************************************
> > > > + * ring.h
> > > > + *
> > > > + * Shared producer-consumer ring macros.
> > > > + *
> > > > + * Permission is hereby granted, free of charge, to any person obtaining a copy
> > > > + * of this software and associated documentation files (the "Software"), to
> > > > + * deal in the Software without restriction, including without limitation the
> > > > + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> > > > + * sell copies of the Software, and to permit persons to whom the Software is
> > > > + * furnished to do so, subject to the following conditions:
> > > > + *
> > > > + * The above copyright notice and this permission notice shall be included in
> > > > + * all copies or substantial portions of the Software.
> > > > + *
> > > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> > > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> > > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> > > > + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> > > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> > > > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> > > > + * DEALINGS IN THE SOFTWARE.
> > > > + *
> > > > + * Tim Deegan and Andrew Warfield November 2004.
> > > > + */
> > > > +
> > > > +#ifndef __XEN_PUBLIC_IO_RING_H__
> > > > +#define __XEN_PUBLIC_IO_RING_H__
> > > > +
> > > > +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> > > > +#define xen_mb() mb()
> > > > +#define xen_rmb() rmb()
> > > > +#define xen_wmb() wmb()
> > > > +#endif
> > > > +
> > > > +typedef unsigned int RING_IDX;
> > > > +
> > > > +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> > > > +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> > > > +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> > > > +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> > > > +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> > > > +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> > > > +
> > > > +/*
> > > > + * Calculate size of a shared ring, given the total available space for the
> > > > + * ring and indexes (_sz), and the name tag of the request/response structure.
> > > > + * A ring contains as many entries as will fit, rounded down to the nearest
> > > > + * power of two (so we can mask with (size-1) to loop around).
> > > > + */
> > > > +#define __CONST_RING_SIZE(_s, _sz) \
> > > > + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> > > > + sizeof(((struct _s##_sring *)0)->ring[0])))
> > > > +/*
> > > > + * The same for passing in an actual pointer instead of a name tag.
> > > > + */
> > > > +#define __RING_SIZE(_s, _sz) \
> > > > + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> > > > +
> > > > +/*
> > > > + * Macros to make the correct C datatypes for a new kind of ring.
> > > > + *
> > > > + * To make a new ring datatype, you need to have two message structures,
> > > > + * let's say request_t, and response_t already defined.
> > > > + *
> > > > + * In a header where you want the ring datatype declared, you then do:
> > > > + *
> > > > + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> > > > + *
> > > > + * These expand out to give you a set of types, as you can see below.
> > > > + * The most important of these are:
> > > > + *
> > > > + * mytag_sring_t - The shared ring.
> > > > + * mytag_front_ring_t - The 'front' half of the ring.
> > > > + * mytag_back_ring_t - The 'back' half of the ring.
> > > > + *
> > > > + * To initialize a ring in your code you need to know the location and size
> > > > + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> > > > + * the front half:
> > > > + *
> > > > + * mytag_front_ring_t front_ring;
> > > > + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> > > > + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > > + *
> > > > + * Initializing the back follows similarly (note that only the front
> > > > + * initializes the shared ring):
> > > > + *
> > > > + * mytag_back_ring_t back_ring;
> > > > + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > > + */
> > > > +
> > > > +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> > > > + \
> > > > +/* Shared ring entry */ \
> > > > +union __name##_sring_entry { \
> > > > + __req_t req; \
> > > > + __rsp_t rsp; \
> > > > +}; \
> > > > + \
> > > > +/* Shared ring page */ \
> > > > +struct __name##_sring { \
> > > > + RING_IDX req_prod, req_event; \
> > > > + RING_IDX rsp_prod, rsp_event; \
> > > > + union { \
> > > > + struct { \
> > > > + uint8_t smartpoll_active; \
> > > > + } netif; \
> > > > + struct { \
> > > > + uint8_t msg; \
> > > > + } tapif_user; \
> > > > + uint8_t pvt_pad[4]; \
> > > > + } pvt; \
> > > > + uint8_t __pad[44]; \
> > > > + union __name##_sring_entry ring[1]; /* variable-length */ \
> > > > +}; \
> > > > + \
> > > > +/* "Front" end's private variables */ \
> > > > +struct __name##_front_ring { \
> > > > + RING_IDX req_prod_pvt; \
> > > > + RING_IDX rsp_cons; \
> > > > + unsigned int nr_ents; \
> > > > + struct __name##_sring *sring; \
> > > > +}; \
> > > > + \
> > > > +/* "Back" end's private variables */ \
> > > > +struct __name##_back_ring { \
> > > > + RING_IDX rsp_prod_pvt; \
> > > > + RING_IDX req_cons; \
> > > > + unsigned int nr_ents; \
> > > > + struct __name##_sring *sring; \
> > > > +}; \
> > > > + \
> > > > +/* Syntactic sugar */ \
> > > > +typedef struct __name##_sring __name##_sring_t; \
> > > > +typedef struct __name##_front_ring __name##_front_ring_t; \
> > > > +typedef struct __name##_back_ring __name##_back_ring_t
> > > > +
> > > > +/*
> > > > + * Macros for manipulating rings.
> > > > + *
> > > > + * FRONT_RING_whatever works on the "front end" of a ring: here
> > > > + * requests are pushed on to the ring and responses taken off it.
> > > > + *
> > > > + * BACK_RING_whatever works on the "back end" of a ring: here
> > > > + * requests are taken off the ring and responses put on.
> > > > + *
> > > > + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> > > > + * This is OK in 1-for-1 request-response situations where the
> > > > + * requestor (front end) never has more than RING_SIZE()-1
> > > > + * outstanding requests.
> > > > + */
> > > > +
> > > > +/* Initialising empty rings */
> > > > +#define SHARED_RING_INIT(_s) do { \
> > > > + (_s)->req_prod = (_s)->rsp_prod = 0; \
> > > > + (_s)->req_event = (_s)->rsp_event = 1; \
> > > > + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> > > > + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> > > > +} while(0)
> > > > +
> > > > +#define FRONT_RING_INIT(_r, _s, __size) do { \
> > > > + (_r)->req_prod_pvt = 0; \
> > > > + (_r)->rsp_cons = 0; \
> > > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > > + (_r)->sring = (_s); \
> > > > +} while (0)
> > > > +
> > > > +#define BACK_RING_INIT(_r, _s, __size) do { \
> > > > + (_r)->rsp_prod_pvt = 0; \
> > > > + (_r)->req_cons = 0; \
> > > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > > + (_r)->sring = (_s); \
> > > > +} while (0)
> > > > +
> > > > +/* How big is this ring? */
> > > > +#define RING_SIZE(_r) \
> > > > + ((_r)->nr_ents)
> > > > +
> > > > +/* Number of free requests (for use on front side only). */
> > > > +#define RING_FREE_REQUESTS(_r) \
> > > > + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> > > > +
> > > > +/* Test if there is an empty slot available on the front ring.
> > > > + * (This is only meaningful from the front. )
> > > > + */
> > > > +#define RING_FULL(_r) \
> > > > + (RING_FREE_REQUESTS(_r) == 0)
> > > > +
> > > > +/* Test if there are outstanding messages to be processed on a ring. */
> > > > +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> > > > + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> > > > +
> > > > +#ifdef __GNUC__
> > > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> > > > + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> > > > + unsigned int rsp = RING_SIZE(_r) - \
> > > > + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> > > > + req < rsp ? req : rsp; \
> > > > +})
> > > > +#else
> > > > +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> > > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> > > > + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> > > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> > > > + ((_r)->sring->req_prod - (_r)->req_cons) : \
> > > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> > > > +#endif
> > > > +
> > > > +/* Direct access to individual ring elements, by index. */
> > > > +#define RING_GET_REQUEST(_r, _idx) \
> > > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> > > > +
> > > > +/*
> > > > + * Get a local copy of a request.
> > > > + *
> > > > + * Use this in preference to RING_GET_REQUEST() so all processing is
> > > > + * done on a local copy that cannot be modified by the other end.
> > > > + *
> > > > + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> > > > + * to be ineffective where _req is a struct which consists of only bitfields.
> > > > + */
> > > > +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> > > > + /* Use volatile to force the copy into _req. */ \
> > > > + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_GET_RESPONSE(_r, _idx) \
> > > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> > > > +
> > > > +/* Loop termination condition: Would the specified index overflow the ring? */
> > > > +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> > > > + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> > > > +
> > > > +/* Ill-behaved frontend determination: Can there be this many requests? */
> > > > +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> > > > + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> > > > +
> > > > +#define RING_PUSH_REQUESTS(_r) do { \
> > > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > > + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> > > > +} while (0)
> > > > +
> > > > +#define RING_PUSH_RESPONSES(_r) do { \
> > > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > > + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> > > > +} while (0)
> > > > +
> > > > +/*
> > > > + * Notification hold-off (req_event and rsp_event):
> > > > + *
> > > > + * When queueing requests or responses on a shared ring, it may not always be
> > > > + * necessary to notify the remote end. For example, if requests are in flight
> > > > + * in a backend, the front may be able to queue further requests without
> > > > + * notifying the back (if the back checks for new requests when it queues
> > > > + * responses).
> > > > + *
> > > > + * When enqueuing requests or responses:
> > > > + *
> > > > + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> > > > + * is a boolean return value. True indicates that the receiver requires an
> > > > + * asynchronous notification.
> > > > + *
> > > > + * After dequeuing requests or responses (before sleeping the connection):
> > > > + *
> > > > + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> > > > + * The second argument is a boolean return value. True indicates that there
> > > > + * are pending messages on the ring (i.e., the connection should not be put
> > > > + * to sleep).
> > > > + *
> > > > + * These macros will set the req_event/rsp_event field to trigger a
> > > > + * notification on the very next message that is enqueued. If you want to
> > > > + * create batches of work (i.e., only receive a notification after several
> > > > + * messages have been enqueued) then you will need to create a customised
> > > > + * version of the FINAL_CHECK macro in your own code, which sets the event
> > > > + * field appropriately.
> > > > + */
> > > > +
> > > > +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > > + RING_IDX __old = (_r)->sring->req_prod; \
> > > > + RING_IDX __new = (_r)->req_prod_pvt; \
> > > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > > + (_r)->sring->req_prod = __new; \
> > > > + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> > > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> > > > + (RING_IDX)(__new - __old)); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > > + RING_IDX __old = (_r)->sring->rsp_prod; \
> > > > + RING_IDX __new = (_r)->rsp_prod_pvt; \
> > > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > > + (_r)->sring->rsp_prod = __new; \
> > > > + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> > > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> > > > + (RING_IDX)(__new - __old)); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > > + if (_work_to_do) break; \
> > > > + (_r)->sring->req_event = (_r)->req_cons + 1; \
> > > > + xen_mb(); \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > > + if (_work_to_do) break; \
> > > > + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> > > > + xen_mb(); \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > > +} while (0)
> > > > +
> > > > +
> > > > +/*
> > > > + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> > > > + * functions to check if there is data on the ring, and to read and
> > > > + * write to them.
> > > > + *
> > > > + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> > > > + * does not define the indexes page. As different protocols can have
> > > > + * extensions to the basic format, this macro allow them to define their
> > > > + * own struct.
> > > > + *
> > > > + * XEN_FLEX_RING_SIZE
> > > > + * Convenience macro to calculate the size of one of the two rings
> > > > + * from the overall order.
> > > > + *
> > > > + * $NAME_mask
> > > > + * Function to apply the size mask to an index, to reduce the index
> > > > + * within the range [0-size].
> > > > + *
> > > > + * $NAME_read_packet
> > > > + * Function to read data from the ring. The amount of data to read is
> > > > + * specified by the "size" argument.
> > > > + *
> > > > + * $NAME_write_packet
> > > > + * Function to write data to the ring. The amount of data to write is
> > > > + * specified by the "size" argument.
> > > > + *
> > > > + * $NAME_get_ring_ptr
> > > > + * Convenience function that returns a pointer to read/write to the
> > > > + * ring at the right location.
> > > > + *
> > > > + * $NAME_data_intf
> > > > + * Indexes page, shared between frontend and backend. It also
> > > > + * contains the array of grant refs.
> > > > + *
> > > > + * $NAME_queued
> > > > + * Function to calculate how many bytes are currently on the ring,
> > > > + * ready to be read. It can also be used to calculate how much free
> > > > + * space is currently on the ring (ring_size - $NAME_queued()).
> > > > + */
> > > > +#define XEN_FLEX_RING_SIZE(order) \
> > > > + (1UL << (order + PAGE_SHIFT - 1))
> > > > +
> > > > +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> > > > +struct name##_data_intf { \
> > > > + RING_IDX in_cons, in_prod; \
> > > > + \
> > > > + uint8_t pad1[56]; \
> > > > + \
> > > > + RING_IDX out_cons, out_prod; \
> > > > + \
> > > > + uint8_t pad2[56]; \
> > > > + \
> > > > + RING_IDX ring_order; \
> > > > + grant_ref_t ref[]; \
> > > > +}; \
> > > > +DEFINE_XEN_FLEX_RING(name);
> > > > +
> > > > +#define DEFINE_XEN_FLEX_RING(name) \
> > > > +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> > > > +{ \
> > > > + return (idx & (ring_size - 1)); \
> > > > +} \
> > > > + \
> > > > +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> > > > +{ \
> > > > + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> > > > +} \
> > > > + \
> > > > +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> > > > + RING_IDX idx, \
> > > > + RING_IDX ring_order) \
> > > > +{ \
> > > > + return buf + name##_mask_order(idx, ring_order); \
> > > > +} \
> > > > + \
> > > > +static inline void name##_read_packet(const unsigned char *buf, \
> > > > + RING_IDX masked_prod, RING_IDX *masked_cons, \
> > > > + RING_IDX ring_size, void *opaque, size_t size) { \
> > > > + if (*masked_cons < masked_prod || \
> > > > + size <= ring_size - *masked_cons) { \
> > > > + memcpy(opaque, buf + *masked_cons, size); \
> > > > + } else { \
> > > > + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> > > > + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> > > > + size - (ring_size - *masked_cons)); \
> > > > + } \
> > > > + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> > > > +} \
> > > > + \
> > > > +static inline void name##_write_packet(unsigned char *buf, \
> > > > + RING_IDX *masked_prod, RING_IDX masked_cons, \
> > > > + RING_IDX ring_size, const void *opaque, size_t size) { \
> > > > + if (*masked_prod < masked_cons || \
> > > > + size <= ring_size - *masked_prod) { \
> > > > + memcpy(buf + *masked_prod, opaque, size); \
> > > > + } else { \
> > > > + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> > > > + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> > > > + size - (ring_size - *masked_prod)); \
> > > > + } \
> > > > + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> > > > +} \
> > > > + \
> > > > +struct name##_data { \
> > > > + unsigned char *in; /* half of the allocation */ \
> > > > + unsigned char *out; /* half of the allocation */ \
> > > > +}; \
> > > > + \
> > > > + \
> > > > +static inline RING_IDX name##_queued(RING_IDX prod, \
> > > > + RING_IDX cons, RING_IDX ring_size) \
> > > > +{ \
> > > > + RING_IDX size; \
> > > > + \
> > > > + if (prod == cons) \
> > > > + return 0; \
> > > > + \
> > > > + prod = name##_mask(prod, ring_size); \
> > > > + cons = name##_mask(cons, ring_size); \
> > > > + \
> > > > + if (prod == cons) \
> > > > + return ring_size; \
> > > > + \
> > > > + if (prod > cons) \
> > > > + size = prod - cons; \
> > > > + else \
> > > > + size = ring_size - (cons - prod); \
> > > > + return size; \
> > > > +};
> > > > +
> > > > +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> > > > +
> > > > +/*
> > > > + * Local variables:
> > > > + * mode: C
> > > > + * c-file-style: "BSD"
> > > > + * c-basic-offset: 4
> > > > + * tab-width: 4
> > > > + * indent-tabs-mode: nil
> > > > + * End:
> > > > + */
> > >
> > >
>
>
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 2/9] xen: import ring.h from xen
@ 2017-03-15 19:04 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 19:04 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Wed, 15 Mar 2017 11:36:12 -0700 (PDT)
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > On Wed, 15 Mar 2017, Greg Kurz wrote:
> > > On Mon, 13 Mar 2017 16:55:53 -0700
> > > Stefano Stabellini <sstabellini@kernel.org> wrote:
> > >
> > > > Do not use the ring.h header installed on the system. Instead, import
> > > > the header into the QEMU codebase. This avoids problems when QEMU is
> > > > built against a Xen version too old to provide all the ring macros.
> > > >
> > >
> > > What kind of problems ?
> >
> > The FLEX macros are only available in Xen 4.9+ (still unreleased).
> > However, aside from these macros, the Xen 9pfs frontends and backends
> > could work fine on any Xen releases. In fact, the Xen public/io headers
> > are only provided as reference.
> >
>
> Ok.
>
> >
> > > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > > CC: anthony.perard@citrix.com
> > > > CC: jgross@suse.com
> > > > ---
> > > > NB: The new macros have not been committed to Xen yet. Do not apply this
> > > > patch until they do.
> > >
> > > Why ? Does this break compat with older Xen ?
> >
> > No, it does not break compatibility. But I think it is a good idea to
> > commit the header to QEMU only after the corresponding Xen header has
> > been accepted. I don't want the two to diverge.
> >
>
> Fair enough but this will put the entire patchset on hold then. When Xen 4.9
> is supposed to be released ?
In a few months, but I don't think we need to wait until the release,
just for the reviewed-by on the new macros, that should come soon.
> > > > ---
> > > > ---
> > > > hw/block/xen_blkif.h | 2 +-
> > > > hw/usb/xen-usb.c | 2 +-
> > > > include/hw/xen/io/ring.h | 455 +++++++++++++++++++++++++++++++++++++++++++++++
> > > > 3 files changed, 457 insertions(+), 2 deletions(-)
> > > > create mode 100644 include/hw/xen/io/ring.h
> > > >
> > > > diff --git a/hw/block/xen_blkif.h b/hw/block/xen_blkif.h
> > > > index 3300b6f..3e6e1ea 100644
> > > > --- a/hw/block/xen_blkif.h
> > > > +++ b/hw/block/xen_blkif.h
> > > > @@ -1,7 +1,7 @@
> > > > #ifndef XEN_BLKIF_H
> > > > #define XEN_BLKIF_H
> > > >
> > > > -#include <xen/io/ring.h>
> > > > +#include "hw/xen/io/ring.h"
> > > > #include <xen/io/blkif.h>
> > > > #include <xen/io/protocols.h>
> > > >
> > > > diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
> > > > index 8e676e6..370b3d9 100644
> > > > --- a/hw/usb/xen-usb.c
> > > > +++ b/hw/usb/xen-usb.c
> > > > @@ -33,7 +33,7 @@
> > > > #include "qapi/qmp/qint.h"
> > > > #include "qapi/qmp/qstring.h"
> > > >
> > > > -#include <xen/io/ring.h>
> > > > +#include "hw/xen/io/ring.h"
> > > > #include <xen/io/usbif.h>
> > > >
> > > > /*
> > > > diff --git a/include/hw/xen/io/ring.h b/include/hw/xen/io/ring.h
> > > > new file mode 100644
> > > > index 0000000..cf01fc3
> > > > --- /dev/null
> > > > +++ b/include/hw/xen/io/ring.h
> > > > @@ -0,0 +1,455 @@
> > > > +/******************************************************************************
> > > > + * ring.h
> > > > + *
> > > > + * Shared producer-consumer ring macros.
> > > > + *
> > > > + * Permission is hereby granted, free of charge, to any person obtaining a copy
> > > > + * of this software and associated documentation files (the "Software"), to
> > > > + * deal in the Software without restriction, including without limitation the
> > > > + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
> > > > + * sell copies of the Software, and to permit persons to whom the Software is
> > > > + * furnished to do so, subject to the following conditions:
> > > > + *
> > > > + * The above copyright notice and this permission notice shall be included in
> > > > + * all copies or substantial portions of the Software.
> > > > + *
> > > > + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> > > > + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> > > > + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
> > > > + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> > > > + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
> > > > + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
> > > > + * DEALINGS IN THE SOFTWARE.
> > > > + *
> > > > + * Tim Deegan and Andrew Warfield November 2004.
> > > > + */
> > > > +
> > > > +#ifndef __XEN_PUBLIC_IO_RING_H__
> > > > +#define __XEN_PUBLIC_IO_RING_H__
> > > > +
> > > > +#if __XEN_INTERFACE_VERSION__ < 0x00030208
> > > > +#define xen_mb() mb()
> > > > +#define xen_rmb() rmb()
> > > > +#define xen_wmb() wmb()
> > > > +#endif
> > > > +
> > > > +typedef unsigned int RING_IDX;
> > > > +
> > > > +/* Round a 32-bit unsigned constant down to the nearest power of two. */
> > > > +#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
> > > > +#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
> > > > +#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
> > > > +#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
> > > > +#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
> > > > +
> > > > +/*
> > > > + * Calculate size of a shared ring, given the total available space for the
> > > > + * ring and indexes (_sz), and the name tag of the request/response structure.
> > > > + * A ring contains as many entries as will fit, rounded down to the nearest
> > > > + * power of two (so we can mask with (size-1) to loop around).
> > > > + */
> > > > +#define __CONST_RING_SIZE(_s, _sz) \
> > > > + (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
> > > > + sizeof(((struct _s##_sring *)0)->ring[0])))
> > > > +/*
> > > > + * The same for passing in an actual pointer instead of a name tag.
> > > > + */
> > > > +#define __RING_SIZE(_s, _sz) \
> > > > + (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
> > > > +
> > > > +/*
> > > > + * Macros to make the correct C datatypes for a new kind of ring.
> > > > + *
> > > > + * To make a new ring datatype, you need to have two message structures,
> > > > + * let's say request_t, and response_t already defined.
> > > > + *
> > > > + * In a header where you want the ring datatype declared, you then do:
> > > > + *
> > > > + * DEFINE_RING_TYPES(mytag, request_t, response_t);
> > > > + *
> > > > + * These expand out to give you a set of types, as you can see below.
> > > > + * The most important of these are:
> > > > + *
> > > > + * mytag_sring_t - The shared ring.
> > > > + * mytag_front_ring_t - The 'front' half of the ring.
> > > > + * mytag_back_ring_t - The 'back' half of the ring.
> > > > + *
> > > > + * To initialize a ring in your code you need to know the location and size
> > > > + * of the shared memory area (PAGE_SIZE, for instance). To initialise
> > > > + * the front half:
> > > > + *
> > > > + * mytag_front_ring_t front_ring;
> > > > + * SHARED_RING_INIT((mytag_sring_t *)shared_page);
> > > > + * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > > + *
> > > > + * Initializing the back follows similarly (note that only the front
> > > > + * initializes the shared ring):
> > > > + *
> > > > + * mytag_back_ring_t back_ring;
> > > > + * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
> > > > + */
> > > > +
> > > > +#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
> > > > + \
> > > > +/* Shared ring entry */ \
> > > > +union __name##_sring_entry { \
> > > > + __req_t req; \
> > > > + __rsp_t rsp; \
> > > > +}; \
> > > > + \
> > > > +/* Shared ring page */ \
> > > > +struct __name##_sring { \
> > > > + RING_IDX req_prod, req_event; \
> > > > + RING_IDX rsp_prod, rsp_event; \
> > > > + union { \
> > > > + struct { \
> > > > + uint8_t smartpoll_active; \
> > > > + } netif; \
> > > > + struct { \
> > > > + uint8_t msg; \
> > > > + } tapif_user; \
> > > > + uint8_t pvt_pad[4]; \
> > > > + } pvt; \
> > > > + uint8_t __pad[44]; \
> > > > + union __name##_sring_entry ring[1]; /* variable-length */ \
> > > > +}; \
> > > > + \
> > > > +/* "Front" end's private variables */ \
> > > > +struct __name##_front_ring { \
> > > > + RING_IDX req_prod_pvt; \
> > > > + RING_IDX rsp_cons; \
> > > > + unsigned int nr_ents; \
> > > > + struct __name##_sring *sring; \
> > > > +}; \
> > > > + \
> > > > +/* "Back" end's private variables */ \
> > > > +struct __name##_back_ring { \
> > > > + RING_IDX rsp_prod_pvt; \
> > > > + RING_IDX req_cons; \
> > > > + unsigned int nr_ents; \
> > > > + struct __name##_sring *sring; \
> > > > +}; \
> > > > + \
> > > > +/* Syntactic sugar */ \
> > > > +typedef struct __name##_sring __name##_sring_t; \
> > > > +typedef struct __name##_front_ring __name##_front_ring_t; \
> > > > +typedef struct __name##_back_ring __name##_back_ring_t
> > > > +
> > > > +/*
> > > > + * Macros for manipulating rings.
> > > > + *
> > > > + * FRONT_RING_whatever works on the "front end" of a ring: here
> > > > + * requests are pushed on to the ring and responses taken off it.
> > > > + *
> > > > + * BACK_RING_whatever works on the "back end" of a ring: here
> > > > + * requests are taken off the ring and responses put on.
> > > > + *
> > > > + * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
> > > > + * This is OK in 1-for-1 request-response situations where the
> > > > + * requestor (front end) never has more than RING_SIZE()-1
> > > > + * outstanding requests.
> > > > + */
> > > > +
> > > > +/* Initialising empty rings */
> > > > +#define SHARED_RING_INIT(_s) do { \
> > > > + (_s)->req_prod = (_s)->rsp_prod = 0; \
> > > > + (_s)->req_event = (_s)->rsp_event = 1; \
> > > > + (void)memset((_s)->pvt.pvt_pad, 0, sizeof((_s)->pvt.pvt_pad)); \
> > > > + (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
> > > > +} while(0)
> > > > +
> > > > +#define FRONT_RING_INIT(_r, _s, __size) do { \
> > > > + (_r)->req_prod_pvt = 0; \
> > > > + (_r)->rsp_cons = 0; \
> > > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > > + (_r)->sring = (_s); \
> > > > +} while (0)
> > > > +
> > > > +#define BACK_RING_INIT(_r, _s, __size) do { \
> > > > + (_r)->rsp_prod_pvt = 0; \
> > > > + (_r)->req_cons = 0; \
> > > > + (_r)->nr_ents = __RING_SIZE(_s, __size); \
> > > > + (_r)->sring = (_s); \
> > > > +} while (0)
> > > > +
> > > > +/* How big is this ring? */
> > > > +#define RING_SIZE(_r) \
> > > > + ((_r)->nr_ents)
> > > > +
> > > > +/* Number of free requests (for use on front side only). */
> > > > +#define RING_FREE_REQUESTS(_r) \
> > > > + (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
> > > > +
> > > > +/* Test if there is an empty slot available on the front ring.
> > > > + * (This is only meaningful from the front. )
> > > > + */
> > > > +#define RING_FULL(_r) \
> > > > + (RING_FREE_REQUESTS(_r) == 0)
> > > > +
> > > > +/* Test if there are outstanding messages to be processed on a ring. */
> > > > +#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
> > > > + ((_r)->sring->rsp_prod - (_r)->rsp_cons)
> > > > +
> > > > +#ifdef __GNUC__
> > > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
> > > > + unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
> > > > + unsigned int rsp = RING_SIZE(_r) - \
> > > > + ((_r)->req_cons - (_r)->rsp_prod_pvt); \
> > > > + req < rsp ? req : rsp; \
> > > > +})
> > > > +#else
> > > > +/* Same as above, but without the nice GCC ({ ... }) syntax. */
> > > > +#define RING_HAS_UNCONSUMED_REQUESTS(_r) \
> > > > + ((((_r)->sring->req_prod - (_r)->req_cons) < \
> > > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt))) ? \
> > > > + ((_r)->sring->req_prod - (_r)->req_cons) : \
> > > > + (RING_SIZE(_r) - ((_r)->req_cons - (_r)->rsp_prod_pvt)))
> > > > +#endif
> > > > +
> > > > +/* Direct access to individual ring elements, by index. */
> > > > +#define RING_GET_REQUEST(_r, _idx) \
> > > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
> > > > +
> > > > +/*
> > > > + * Get a local copy of a request.
> > > > + *
> > > > + * Use this in preference to RING_GET_REQUEST() so all processing is
> > > > + * done on a local copy that cannot be modified by the other end.
> > > > + *
> > > > + * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
> > > > + * to be ineffective where _req is a struct which consists of only bitfields.
> > > > + */
> > > > +#define RING_COPY_REQUEST(_r, _idx, _req) do { \
> > > > + /* Use volatile to force the copy into _req. */ \
> > > > + *(_req) = *(volatile typeof(_req))RING_GET_REQUEST(_r, _idx); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_GET_RESPONSE(_r, _idx) \
> > > > + (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
> > > > +
> > > > +/* Loop termination condition: Would the specified index overflow the ring? */
> > > > +#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
> > > > + (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
> > > > +
> > > > +/* Ill-behaved frontend determination: Can there be this many requests? */
> > > > +#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
> > > > + (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
> > > > +
> > > > +#define RING_PUSH_REQUESTS(_r) do { \
> > > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > > + (_r)->sring->req_prod = (_r)->req_prod_pvt; \
> > > > +} while (0)
> > > > +
> > > > +#define RING_PUSH_RESPONSES(_r) do { \
> > > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > > + (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
> > > > +} while (0)
> > > > +
> > > > +/*
> > > > + * Notification hold-off (req_event and rsp_event):
> > > > + *
> > > > + * When queueing requests or responses on a shared ring, it may not always be
> > > > + * necessary to notify the remote end. For example, if requests are in flight
> > > > + * in a backend, the front may be able to queue further requests without
> > > > + * notifying the back (if the back checks for new requests when it queues
> > > > + * responses).
> > > > + *
> > > > + * When enqueuing requests or responses:
> > > > + *
> > > > + * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
> > > > + * is a boolean return value. True indicates that the receiver requires an
> > > > + * asynchronous notification.
> > > > + *
> > > > + * After dequeuing requests or responses (before sleeping the connection):
> > > > + *
> > > > + * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
> > > > + * The second argument is a boolean return value. True indicates that there
> > > > + * are pending messages on the ring (i.e., the connection should not be put
> > > > + * to sleep).
> > > > + *
> > > > + * These macros will set the req_event/rsp_event field to trigger a
> > > > + * notification on the very next message that is enqueued. If you want to
> > > > + * create batches of work (i.e., only receive a notification after several
> > > > + * messages have been enqueued) then you will need to create a customised
> > > > + * version of the FINAL_CHECK macro in your own code, which sets the event
> > > > + * field appropriately.
> > > > + */
> > > > +
> > > > +#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > > + RING_IDX __old = (_r)->sring->req_prod; \
> > > > + RING_IDX __new = (_r)->req_prod_pvt; \
> > > > + xen_wmb(); /* back sees requests /before/ updated producer index */ \
> > > > + (_r)->sring->req_prod = __new; \
> > > > + xen_mb(); /* back sees new requests /before/ we check req_event */ \
> > > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
> > > > + (RING_IDX)(__new - __old)); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
> > > > + RING_IDX __old = (_r)->sring->rsp_prod; \
> > > > + RING_IDX __new = (_r)->rsp_prod_pvt; \
> > > > + xen_wmb(); /* front sees resps /before/ updated producer index */ \
> > > > + (_r)->sring->rsp_prod = __new; \
> > > > + xen_mb(); /* front sees new resps /before/ we check rsp_event */ \
> > > > + (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
> > > > + (RING_IDX)(__new - __old)); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > > + if (_work_to_do) break; \
> > > > + (_r)->sring->req_event = (_r)->req_cons + 1; \
> > > > + xen_mb(); \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
> > > > +} while (0)
> > > > +
> > > > +#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > > + if (_work_to_do) break; \
> > > > + (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
> > > > + xen_mb(); \
> > > > + (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
> > > > +} while (0)
> > > > +
> > > > +
> > > > +/*
> > > > + * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
> > > > + * functions to check if there is data on the ring, and to read and
> > > > + * write to them.
> > > > + *
> > > > + * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
> > > > + * does not define the indexes page. As different protocols can have
> > > > + * extensions to the basic format, this macro allow them to define their
> > > > + * own struct.
> > > > + *
> > > > + * XEN_FLEX_RING_SIZE
> > > > + * Convenience macro to calculate the size of one of the two rings
> > > > + * from the overall order.
> > > > + *
> > > > + * $NAME_mask
> > > > + * Function to apply the size mask to an index, to reduce the index
> > > > + * within the range [0-size].
> > > > + *
> > > > + * $NAME_read_packet
> > > > + * Function to read data from the ring. The amount of data to read is
> > > > + * specified by the "size" argument.
> > > > + *
> > > > + * $NAME_write_packet
> > > > + * Function to write data to the ring. The amount of data to write is
> > > > + * specified by the "size" argument.
> > > > + *
> > > > + * $NAME_get_ring_ptr
> > > > + * Convenience function that returns a pointer to read/write to the
> > > > + * ring at the right location.
> > > > + *
> > > > + * $NAME_data_intf
> > > > + * Indexes page, shared between frontend and backend. It also
> > > > + * contains the array of grant refs.
> > > > + *
> > > > + * $NAME_queued
> > > > + * Function to calculate how many bytes are currently on the ring,
> > > > + * ready to be read. It can also be used to calculate how much free
> > > > + * space is currently on the ring (ring_size - $NAME_queued()).
> > > > + */
> > > > +#define XEN_FLEX_RING_SIZE(order) \
> > > > + (1UL << (order + PAGE_SHIFT - 1))
> > > > +
> > > > +#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
> > > > +struct name##_data_intf { \
> > > > + RING_IDX in_cons, in_prod; \
> > > > + \
> > > > + uint8_t pad1[56]; \
> > > > + \
> > > > + RING_IDX out_cons, out_prod; \
> > > > + \
> > > > + uint8_t pad2[56]; \
> > > > + \
> > > > + RING_IDX ring_order; \
> > > > + grant_ref_t ref[]; \
> > > > +}; \
> > > > +DEFINE_XEN_FLEX_RING(name);
> > > > +
> > > > +#define DEFINE_XEN_FLEX_RING(name) \
> > > > +static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
> > > > +{ \
> > > > + return (idx & (ring_size - 1)); \
> > > > +} \
> > > > + \
> > > > +static inline RING_IDX name##_mask_order(RING_IDX idx, RING_IDX ring_order) \
> > > > +{ \
> > > > + return (idx & (XEN_FLEX_RING_SIZE(ring_order) - 1)); \
> > > > +} \
> > > > + \
> > > > +static inline unsigned char* name##_get_ring_ptr(unsigned char *buf, \
> > > > + RING_IDX idx, \
> > > > + RING_IDX ring_order) \
> > > > +{ \
> > > > + return buf + name##_mask_order(idx, ring_order); \
> > > > +} \
> > > > + \
> > > > +static inline void name##_read_packet(const unsigned char *buf, \
> > > > + RING_IDX masked_prod, RING_IDX *masked_cons, \
> > > > + RING_IDX ring_size, void *opaque, size_t size) { \
> > > > + if (*masked_cons < masked_prod || \
> > > > + size <= ring_size - *masked_cons) { \
> > > > + memcpy(opaque, buf + *masked_cons, size); \
> > > > + } else { \
> > > > + memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
> > > > + memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
> > > > + size - (ring_size - *masked_cons)); \
> > > > + } \
> > > > + *masked_cons = name##_mask(*masked_cons + size, ring_size); \
> > > > +} \
> > > > + \
> > > > +static inline void name##_write_packet(unsigned char *buf, \
> > > > + RING_IDX *masked_prod, RING_IDX masked_cons, \
> > > > + RING_IDX ring_size, const void *opaque, size_t size) { \
> > > > + if (*masked_prod < masked_cons || \
> > > > + size <= ring_size - *masked_prod) { \
> > > > + memcpy(buf + *masked_prod, opaque, size); \
> > > > + } else { \
> > > > + memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
> > > > + memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
> > > > + size - (ring_size - *masked_prod)); \
> > > > + } \
> > > > + *masked_prod = name##_mask(*masked_prod + size, ring_size); \
> > > > +} \
> > > > + \
> > > > +struct name##_data { \
> > > > + unsigned char *in; /* half of the allocation */ \
> > > > + unsigned char *out; /* half of the allocation */ \
> > > > +}; \
> > > > + \
> > > > + \
> > > > +static inline RING_IDX name##_queued(RING_IDX prod, \
> > > > + RING_IDX cons, RING_IDX ring_size) \
> > > > +{ \
> > > > + RING_IDX size; \
> > > > + \
> > > > + if (prod == cons) \
> > > > + return 0; \
> > > > + \
> > > > + prod = name##_mask(prod, ring_size); \
> > > > + cons = name##_mask(cons, ring_size); \
> > > > + \
> > > > + if (prod == cons) \
> > > > + return ring_size; \
> > > > + \
> > > > + if (prod > cons) \
> > > > + size = prod - cons; \
> > > > + else \
> > > > + size = ring_size - (cons - prod); \
> > > > + return size; \
> > > > +};
> > > > +
> > > > +#endif /* __XEN_PUBLIC_IO_RING_H__ */
> > > > +
> > > > +/*
> > > > + * Local variables:
> > > > + * mode: C
> > > > + * c-file-style: "BSD"
> > > > + * c-basic-offset: 4
> > > > + * tab-width: 4
> > > > + * indent-tabs-mode: nil
> > > > + * End:
> > > > + */
> > >
> > >
>
>
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Xen-devel@lists.xen.org
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^ permalink raw reply [flat|nested] 72+ messages in thread
* [Qemu-devel] [PATCH v2 3/9] xen: introduce the header file for the Xen 9pfs transport protocol
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:55 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross
It uses the new ring.h macros to declare rings and interfaces.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
---
hw/9pfs/xen_9pfs.h | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
create mode 100644 hw/9pfs/xen_9pfs.h
diff --git a/hw/9pfs/xen_9pfs.h b/hw/9pfs/xen_9pfs.h
new file mode 100644
index 0000000..c4e8901
--- /dev/null
+++ b/hw/9pfs/xen_9pfs.h
@@ -0,0 +1,20 @@
+#ifndef XEN_9PFS_H
+#define XEN_9PFS_H
+
+#include "hw/xen/io/ring.h"
+#include <xen/io/protocols.h>
+
+struct xen_9pfs_header {
+ uint32_t size;
+ uint8_t id;
+ uint16_t tag;
+
+ /* uint8_t sdata[]; */
+} __attribute__((packed));
+
+#define PAGE_SHIFT XC_PAGE_SHIFT
+#define XEN_9PFS_RING_ORDER 6
+#define XEN_9PFS_RING_SIZE XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
+DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
+
+#endif
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 3/9] xen: introduce the header file for the Xen 9pfs transport protocol
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, anthony.perard,
xen-devel
It uses the new ring.h macros to declare rings and interfaces.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
---
hw/9pfs/xen_9pfs.h | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
create mode 100644 hw/9pfs/xen_9pfs.h
diff --git a/hw/9pfs/xen_9pfs.h b/hw/9pfs/xen_9pfs.h
new file mode 100644
index 0000000..c4e8901
--- /dev/null
+++ b/hw/9pfs/xen_9pfs.h
@@ -0,0 +1,20 @@
+#ifndef XEN_9PFS_H
+#define XEN_9PFS_H
+
+#include "hw/xen/io/ring.h"
+#include <xen/io/protocols.h>
+
+struct xen_9pfs_header {
+ uint32_t size;
+ uint8_t id;
+ uint16_t tag;
+
+ /* uint8_t sdata[]; */
+} __attribute__((packed));
+
+#define PAGE_SHIFT XC_PAGE_SHIFT
+#define XEN_9PFS_RING_ORDER 6
+#define XEN_9PFS_RING_SIZE XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
+DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
+
+#endif
--
1.9.1
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^ permalink raw reply related [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 3/9] xen: introduce the header file for the Xen 9pfs transport protocol
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-15 9:06 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 9:06 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini, jgross
[-- Attachment #1: Type: text/plain, Size: 1903 bytes --]
On Mon, 13 Mar 2017 16:55:54 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> It uses the new ring.h macros to declare rings and interfaces.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> ---
> hw/9pfs/xen_9pfs.h | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
> create mode 100644 hw/9pfs/xen_9pfs.h
>
This header file has only one user: please move its content to
hw/9pfs/xen-9p-backend.c (except the 9P header structure, see
below).
> diff --git a/hw/9pfs/xen_9pfs.h b/hw/9pfs/xen_9pfs.h
> new file mode 100644
> index 0000000..c4e8901
> --- /dev/null
> +++ b/hw/9pfs/xen_9pfs.h
> @@ -0,0 +1,20 @@
> +#ifndef XEN_9PFS_H
> +#define XEN_9PFS_H
> +
> +#include "hw/xen/io/ring.h"
> +#include <xen/io/protocols.h>
> +
> +struct xen_9pfs_header {
> + uint32_t size;
> + uint8_t id;
> + uint16_t tag;
> +
> + /* uint8_t sdata[]; */
This doesn't seem useful.
> +} __attribute__((packed));
> +
A few remarks:
- this is a 9P message header actually, which is also used with virtio,
- QEMU coding style requires a typedef in CamelCase,
- the 9P protocol explicitely uses little-endian ordering. Since we
don't have endian-specific types, it makes sense to indicate that
when naming the fields.
- we have a QEMU_PACKED macro which seems to be used a lot more than
the gcc syntax
Please define a new type in hw/9pfs/9p.h and use it in both transports.
Something like:
typedef struct {
uint32_t size_le;
uint8_t id;
uint16_t tag_le;
} QEMU_PACKED P9MsgHeader;
> +#define PAGE_SHIFT XC_PAGE_SHIFT
I don't see any user for this in hw/9pfs/xen-9p-backend.c
> +#define XEN_9PFS_RING_ORDER 6
> +#define XEN_9PFS_RING_SIZE XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
> +DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
> +
> +#endif
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 3/9] xen: introduce the header file for the Xen 9pfs transport protocol
@ 2017-03-15 9:06 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 9:06 UTC (permalink / raw)
To: Stefano Stabellini
Cc: anthony.perard, xen-devel, Stefano Stabellini, qemu-devel, jgross
[-- Attachment #1.1: Type: text/plain, Size: 1903 bytes --]
On Mon, 13 Mar 2017 16:55:54 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> It uses the new ring.h macros to declare rings and interfaces.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> ---
> hw/9pfs/xen_9pfs.h | 20 ++++++++++++++++++++
> 1 file changed, 20 insertions(+)
> create mode 100644 hw/9pfs/xen_9pfs.h
>
This header file has only one user: please move its content to
hw/9pfs/xen-9p-backend.c (except the 9P header structure, see
below).
> diff --git a/hw/9pfs/xen_9pfs.h b/hw/9pfs/xen_9pfs.h
> new file mode 100644
> index 0000000..c4e8901
> --- /dev/null
> +++ b/hw/9pfs/xen_9pfs.h
> @@ -0,0 +1,20 @@
> +#ifndef XEN_9PFS_H
> +#define XEN_9PFS_H
> +
> +#include "hw/xen/io/ring.h"
> +#include <xen/io/protocols.h>
> +
> +struct xen_9pfs_header {
> + uint32_t size;
> + uint8_t id;
> + uint16_t tag;
> +
> + /* uint8_t sdata[]; */
This doesn't seem useful.
> +} __attribute__((packed));
> +
A few remarks:
- this is a 9P message header actually, which is also used with virtio,
- QEMU coding style requires a typedef in CamelCase,
- the 9P protocol explicitely uses little-endian ordering. Since we
don't have endian-specific types, it makes sense to indicate that
when naming the fields.
- we have a QEMU_PACKED macro which seems to be used a lot more than
the gcc syntax
Please define a new type in hw/9pfs/9p.h and use it in both transports.
Something like:
typedef struct {
uint32_t size_le;
uint8_t id;
uint16_t tag_le;
} QEMU_PACKED P9MsgHeader;
> +#define PAGE_SHIFT XC_PAGE_SHIFT
I don't see any user for this in hw/9pfs/xen-9p-backend.c
> +#define XEN_9PFS_RING_ORDER 6
> +#define XEN_9PFS_RING_SIZE XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
> +DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
> +
> +#endif
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 3/9] xen: introduce the header file for the Xen 9pfs transport protocol
2017-03-15 9:06 ` Greg Kurz
@ 2017-03-15 19:02 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 19:02 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard,
Stefano Stabellini, jgross
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:54 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > It uses the new ring.h macros to declare rings and interfaces.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > ---
> > hw/9pfs/xen_9pfs.h | 20 ++++++++++++++++++++
> > 1 file changed, 20 insertions(+)
> > create mode 100644 hw/9pfs/xen_9pfs.h
> >
>
> This header file has only one user: please move its content to
> hw/9pfs/xen-9p-backend.c (except the 9P header structure, see
> below).
OK, I can do that. There is going to be a very similar header in the Xen
tree under xen/include/public/io
(http://marc.info/?l=xen-devel&m=148952997709142), but from QEMU point
of view, it makes sense to fold it in xen-9p-backend.c.
> > diff --git a/hw/9pfs/xen_9pfs.h b/hw/9pfs/xen_9pfs.h
> > new file mode 100644
> > index 0000000..c4e8901
> > --- /dev/null
> > +++ b/hw/9pfs/xen_9pfs.h
> > @@ -0,0 +1,20 @@
> > +#ifndef XEN_9PFS_H
> > +#define XEN_9PFS_H
> > +
> > +#include "hw/xen/io/ring.h"
> > +#include <xen/io/protocols.h>
> > +
> > +struct xen_9pfs_header {
> > + uint32_t size;
> > + uint8_t id;
> > + uint16_t tag;
> > +
> > + /* uint8_t sdata[]; */
>
> This doesn't seem useful.
I'll remove
> > +} __attribute__((packed));
> > +
>
> A few remarks:
> - this is a 9P message header actually, which is also used with virtio,
> - QEMU coding style requires a typedef in CamelCase,
> - the 9P protocol explicitely uses little-endian ordering. Since we
> don't have endian-specific types, it makes sense to indicate that
> when naming the fields.
> - we have a QEMU_PACKED macro which seems to be used a lot more than
> the gcc syntax
>
> Please define a new type in hw/9pfs/9p.h and use it in both transports.
> Something like:
>
> typedef struct {
> uint32_t size_le;
> uint8_t id;
> uint16_t tag_le;
> } QEMU_PACKED P9MsgHeader;
OK
> > +#define PAGE_SHIFT XC_PAGE_SHIFT
>
> I don't see any user for this in hw/9pfs/xen-9p-backend.c
PAGE_SHIFT is used by the macros below, but the original Xen headers
don't have the PAGE_SHIFT definition, so, for the sake of keeping the
two in sync, I didn't add it there.
> > +#define XEN_9PFS_RING_ORDER 6
> > +#define XEN_9PFS_RING_SIZE XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
> > +DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
> > +
> > +#endif
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 3/9] xen: introduce the header file for the Xen 9pfs transport protocol
@ 2017-03-15 19:02 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 19:02 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:54 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > It uses the new ring.h macros to declare rings and interfaces.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > ---
> > hw/9pfs/xen_9pfs.h | 20 ++++++++++++++++++++
> > 1 file changed, 20 insertions(+)
> > create mode 100644 hw/9pfs/xen_9pfs.h
> >
>
> This header file has only one user: please move its content to
> hw/9pfs/xen-9p-backend.c (except the 9P header structure, see
> below).
OK, I can do that. There is going to be a very similar header in the Xen
tree under xen/include/public/io
(http://marc.info/?l=xen-devel&m=148952997709142), but from QEMU point
of view, it makes sense to fold it in xen-9p-backend.c.
> > diff --git a/hw/9pfs/xen_9pfs.h b/hw/9pfs/xen_9pfs.h
> > new file mode 100644
> > index 0000000..c4e8901
> > --- /dev/null
> > +++ b/hw/9pfs/xen_9pfs.h
> > @@ -0,0 +1,20 @@
> > +#ifndef XEN_9PFS_H
> > +#define XEN_9PFS_H
> > +
> > +#include "hw/xen/io/ring.h"
> > +#include <xen/io/protocols.h>
> > +
> > +struct xen_9pfs_header {
> > + uint32_t size;
> > + uint8_t id;
> > + uint16_t tag;
> > +
> > + /* uint8_t sdata[]; */
>
> This doesn't seem useful.
I'll remove
> > +} __attribute__((packed));
> > +
>
> A few remarks:
> - this is a 9P message header actually, which is also used with virtio,
> - QEMU coding style requires a typedef in CamelCase,
> - the 9P protocol explicitely uses little-endian ordering. Since we
> don't have endian-specific types, it makes sense to indicate that
> when naming the fields.
> - we have a QEMU_PACKED macro which seems to be used a lot more than
> the gcc syntax
>
> Please define a new type in hw/9pfs/9p.h and use it in both transports.
> Something like:
>
> typedef struct {
> uint32_t size_le;
> uint8_t id;
> uint16_t tag_le;
> } QEMU_PACKED P9MsgHeader;
OK
> > +#define PAGE_SHIFT XC_PAGE_SHIFT
>
> I don't see any user for this in hw/9pfs/xen-9p-backend.c
PAGE_SHIFT is used by the macros below, but the original Xen headers
don't have the PAGE_SHIFT definition, so, for the sake of keeping the
two in sync, I didn't add it there.
> > +#define XEN_9PFS_RING_ORDER 6
> > +#define XEN_9PFS_RING_SIZE XEN_FLEX_RING_SIZE(XEN_9PFS_RING_ORDER)
> > +DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
> > +
> > +#endif
_______________________________________________
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Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* [Qemu-devel] [PATCH v2 4/9] xen/9pfs: introduce Xen 9pfs backend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:55 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross, Aneesh Kumar K.V
Introduce the Xen 9pfs backend: add struct XenDevOps to register as a
Xen backend and add struct V9fsTransport to register as v9fs transport.
All functions are empty stubs for now.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 96 insertions(+)
create mode 100644 hw/9pfs/xen-9p-backend.c
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
new file mode 100644
index 0000000..35032d3
--- /dev/null
+++ b/hw/9pfs/xen-9p-backend.c
@@ -0,0 +1,96 @@
+/*
+ * Xen 9p backend
+ *
+ * Copyright Aporeto 2017
+ *
+ * Authors:
+ * Stefano Stabellini <stefano@aporeto.com>
+ *
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/hw.h"
+#include "hw/9pfs/9p.h"
+#include "hw/xen/xen_backend.h"
+#include "xen_9pfs.h"
+#include "qemu/config-file.h"
+#include "fsdev/qemu-fsdev.h"
+
+typedef struct Xen9pfsDev {
+ struct XenDevice xendev; /* must be first */
+} Xen9pfsDev;
+
+static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
+ size_t offset,
+ const char *fmt,
+ va_list ap)
+{
+ return 0;
+}
+
+static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
+ size_t offset,
+ const char *fmt,
+ va_list ap)
+{
+ return 0;
+}
+
+static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
+ struct iovec **piov,
+ unsigned int *pniov)
+{
+}
+
+static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
+ struct iovec **piov,
+ unsigned int *pniov,
+ size_t size)
+{
+}
+
+static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
+{
+}
+
+static const struct V9fsTransport xen_9p_transport = {
+ .pdu_vmarshal = xen_9pfs_pdu_vmarshal,
+ .pdu_vunmarshal = xen_9pfs_pdu_vunmarshal,
+ .init_in_iov_from_pdu = xen_9pfs_init_in_iov_from_pdu,
+ .init_out_iov_from_pdu = xen_9pfs_init_out_iov_from_pdu,
+ .push_and_notify = xen_9pfs_push_and_notify,
+};
+
+static int xen_9pfs_init(struct XenDevice *xendev)
+{
+ return 0;
+}
+
+static int xen_9pfs_free(struct XenDevice *xendev)
+{
+ return -1;
+}
+
+static int xen_9pfs_connect(struct XenDevice *xendev)
+{
+ return 0;
+}
+
+static void xen_9pfs_alloc(struct XenDevice *xendev)
+{
+}
+
+static void xen_9pfs_disconnect(struct XenDevice *xendev)
+{
+}
+
+struct XenDevOps xen_9pfs_ops = {
+ .size = sizeof(Xen9pfsDev),
+ .flags = DEVOPS_FLAG_NEED_GNTDEV,
+ .alloc = xen_9pfs_alloc,
+ .init = xen_9pfs_init,
+ .initialise = xen_9pfs_connect,
+ .disconnect = xen_9pfs_disconnect,
+ .free = xen_9pfs_free,
+};
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 4/9] xen/9pfs: introduce Xen 9pfs backend
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
Introduce the Xen 9pfs backend: add struct XenDevOps to register as a
Xen backend and add struct V9fsTransport to register as v9fs transport.
All functions are empty stubs for now.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 96 insertions(+)
create mode 100644 hw/9pfs/xen-9p-backend.c
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
new file mode 100644
index 0000000..35032d3
--- /dev/null
+++ b/hw/9pfs/xen-9p-backend.c
@@ -0,0 +1,96 @@
+/*
+ * Xen 9p backend
+ *
+ * Copyright Aporeto 2017
+ *
+ * Authors:
+ * Stefano Stabellini <stefano@aporeto.com>
+ *
+ */
+
+#include "qemu/osdep.h"
+
+#include "hw/hw.h"
+#include "hw/9pfs/9p.h"
+#include "hw/xen/xen_backend.h"
+#include "xen_9pfs.h"
+#include "qemu/config-file.h"
+#include "fsdev/qemu-fsdev.h"
+
+typedef struct Xen9pfsDev {
+ struct XenDevice xendev; /* must be first */
+} Xen9pfsDev;
+
+static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
+ size_t offset,
+ const char *fmt,
+ va_list ap)
+{
+ return 0;
+}
+
+static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
+ size_t offset,
+ const char *fmt,
+ va_list ap)
+{
+ return 0;
+}
+
+static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
+ struct iovec **piov,
+ unsigned int *pniov)
+{
+}
+
+static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
+ struct iovec **piov,
+ unsigned int *pniov,
+ size_t size)
+{
+}
+
+static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
+{
+}
+
+static const struct V9fsTransport xen_9p_transport = {
+ .pdu_vmarshal = xen_9pfs_pdu_vmarshal,
+ .pdu_vunmarshal = xen_9pfs_pdu_vunmarshal,
+ .init_in_iov_from_pdu = xen_9pfs_init_in_iov_from_pdu,
+ .init_out_iov_from_pdu = xen_9pfs_init_out_iov_from_pdu,
+ .push_and_notify = xen_9pfs_push_and_notify,
+};
+
+static int xen_9pfs_init(struct XenDevice *xendev)
+{
+ return 0;
+}
+
+static int xen_9pfs_free(struct XenDevice *xendev)
+{
+ return -1;
+}
+
+static int xen_9pfs_connect(struct XenDevice *xendev)
+{
+ return 0;
+}
+
+static void xen_9pfs_alloc(struct XenDevice *xendev)
+{
+}
+
+static void xen_9pfs_disconnect(struct XenDevice *xendev)
+{
+}
+
+struct XenDevOps xen_9pfs_ops = {
+ .size = sizeof(Xen9pfsDev),
+ .flags = DEVOPS_FLAG_NEED_GNTDEV,
+ .alloc = xen_9pfs_alloc,
+ .init = xen_9pfs_init,
+ .initialise = xen_9pfs_connect,
+ .disconnect = xen_9pfs_disconnect,
+ .free = xen_9pfs_free,
+};
--
1.9.1
_______________________________________________
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Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 4/9] xen/9pfs: introduce Xen 9pfs backend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-14 7:11 ` Juergen Gross
-1 siblings, 0 replies; 72+ messages in thread
From: Juergen Gross @ 2017-03-14 7:11 UTC (permalink / raw)
To: Stefano Stabellini, qemu-devel
Cc: xen-devel, anthony.perard, groug, Stefano Stabellini, Aneesh Kumar K.V
On 14/03/17 00:55, Stefano Stabellini wrote:
> Introduce the Xen 9pfs backend: add struct XenDevOps to register as a
> Xen backend and add struct V9fsTransport to register as v9fs transport.
>
> All functions are empty stubs for now.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> Reviewed-by: Greg Kurz <groug@kaod.org>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 96 insertions(+)
> create mode 100644 hw/9pfs/xen-9p-backend.c
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> new file mode 100644
> index 0000000..35032d3
> --- /dev/null
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -0,0 +1,96 @@
> +/*
> + * Xen 9p backend
> + *
> + * Copyright Aporeto 2017
> + *
> + * Authors:
> + * Stefano Stabellini <stefano@aporeto.com>
> + *
> + */
> +
> +#include "qemu/osdep.h"
> +
> +#include "hw/hw.h"
> +#include "hw/9pfs/9p.h"
> +#include "hw/xen/xen_backend.h"
> +#include "xen_9pfs.h"
> +#include "qemu/config-file.h"
> +#include "fsdev/qemu-fsdev.h"
> +
> +typedef struct Xen9pfsDev {
> + struct XenDevice xendev; /* must be first */
> +} Xen9pfsDev;
> +
> +static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> + size_t offset,
> + const char *fmt,
> + va_list ap)
> +{
> + return 0;
> +}
> +
> +static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> + size_t offset,
> + const char *fmt,
> + va_list ap)
> +{
> + return 0;
> +}
> +
> +static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> + struct iovec **piov,
> + unsigned int *pniov)
> +{
> +}
> +
> +static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> + struct iovec **piov,
> + unsigned int *pniov,
> + size_t size)
> +{
> +}
> +
> +static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> +{
> +}
> +
> +static const struct V9fsTransport xen_9p_transport = {
> + .pdu_vmarshal = xen_9pfs_pdu_vmarshal,
> + .pdu_vunmarshal = xen_9pfs_pdu_vunmarshal,
> + .init_in_iov_from_pdu = xen_9pfs_init_in_iov_from_pdu,
> + .init_out_iov_from_pdu = xen_9pfs_init_out_iov_from_pdu,
> + .push_and_notify = xen_9pfs_push_and_notify,
> +};
> +
> +static int xen_9pfs_init(struct XenDevice *xendev)
> +{
> + return 0;
> +}
> +
> +static int xen_9pfs_free(struct XenDevice *xendev)
> +{
> + return -1;
> +}
> +
> +static int xen_9pfs_connect(struct XenDevice *xendev)
> +{
> + return 0;
> +}
> +
> +static void xen_9pfs_alloc(struct XenDevice *xendev)
> +{
> +}
> +
> +static void xen_9pfs_disconnect(struct XenDevice *xendev)
> +{
> +}
> +
> +struct XenDevOps xen_9pfs_ops = {
> + .size = sizeof(Xen9pfsDev),
> + .flags = DEVOPS_FLAG_NEED_GNTDEV,
> + .alloc = xen_9pfs_alloc,
> + .init = xen_9pfs_init,
> + .initialise = xen_9pfs_connect,
Alignment?
> + .disconnect = xen_9pfs_disconnect,
> + .free = xen_9pfs_free,
> +};
>
Juergen
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 4/9] xen/9pfs: introduce Xen 9pfs backend
@ 2017-03-14 7:11 ` Juergen Gross
0 siblings, 0 replies; 72+ messages in thread
From: Juergen Gross @ 2017-03-14 7:11 UTC (permalink / raw)
To: Stefano Stabellini, qemu-devel
Cc: anthony.perard, xen-devel, Stefano Stabellini, groug, Aneesh Kumar K.V
On 14/03/17 00:55, Stefano Stabellini wrote:
> Introduce the Xen 9pfs backend: add struct XenDevOps to register as a
> Xen backend and add struct V9fsTransport to register as v9fs transport.
>
> All functions are empty stubs for now.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> Reviewed-by: Greg Kurz <groug@kaod.org>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 96 insertions(+)
> create mode 100644 hw/9pfs/xen-9p-backend.c
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> new file mode 100644
> index 0000000..35032d3
> --- /dev/null
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -0,0 +1,96 @@
> +/*
> + * Xen 9p backend
> + *
> + * Copyright Aporeto 2017
> + *
> + * Authors:
> + * Stefano Stabellini <stefano@aporeto.com>
> + *
> + */
> +
> +#include "qemu/osdep.h"
> +
> +#include "hw/hw.h"
> +#include "hw/9pfs/9p.h"
> +#include "hw/xen/xen_backend.h"
> +#include "xen_9pfs.h"
> +#include "qemu/config-file.h"
> +#include "fsdev/qemu-fsdev.h"
> +
> +typedef struct Xen9pfsDev {
> + struct XenDevice xendev; /* must be first */
> +} Xen9pfsDev;
> +
> +static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> + size_t offset,
> + const char *fmt,
> + va_list ap)
> +{
> + return 0;
> +}
> +
> +static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> + size_t offset,
> + const char *fmt,
> + va_list ap)
> +{
> + return 0;
> +}
> +
> +static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> + struct iovec **piov,
> + unsigned int *pniov)
> +{
> +}
> +
> +static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> + struct iovec **piov,
> + unsigned int *pniov,
> + size_t size)
> +{
> +}
> +
> +static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> +{
> +}
> +
> +static const struct V9fsTransport xen_9p_transport = {
> + .pdu_vmarshal = xen_9pfs_pdu_vmarshal,
> + .pdu_vunmarshal = xen_9pfs_pdu_vunmarshal,
> + .init_in_iov_from_pdu = xen_9pfs_init_in_iov_from_pdu,
> + .init_out_iov_from_pdu = xen_9pfs_init_out_iov_from_pdu,
> + .push_and_notify = xen_9pfs_push_and_notify,
> +};
> +
> +static int xen_9pfs_init(struct XenDevice *xendev)
> +{
> + return 0;
> +}
> +
> +static int xen_9pfs_free(struct XenDevice *xendev)
> +{
> + return -1;
> +}
> +
> +static int xen_9pfs_connect(struct XenDevice *xendev)
> +{
> + return 0;
> +}
> +
> +static void xen_9pfs_alloc(struct XenDevice *xendev)
> +{
> +}
> +
> +static void xen_9pfs_disconnect(struct XenDevice *xendev)
> +{
> +}
> +
> +struct XenDevOps xen_9pfs_ops = {
> + .size = sizeof(Xen9pfsDev),
> + .flags = DEVOPS_FLAG_NEED_GNTDEV,
> + .alloc = xen_9pfs_alloc,
> + .init = xen_9pfs_init,
> + .initialise = xen_9pfs_connect,
Alignment?
> + .disconnect = xen_9pfs_disconnect,
> + .free = xen_9pfs_free,
> +};
>
Juergen
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https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 4/9] xen/9pfs: introduce Xen 9pfs backend
2017-03-14 7:11 ` Juergen Gross
@ 2017-03-14 20:07 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 20:07 UTC (permalink / raw)
To: Juergen Gross
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard, groug,
Stefano Stabellini, Aneesh Kumar K.V
On Tue, 14 Mar 2017, Juergen Gross wrote:
> On 14/03/17 00:55, Stefano Stabellini wrote:
> > Introduce the Xen 9pfs backend: add struct XenDevOps to register as a
> > Xen backend and add struct V9fsTransport to register as v9fs transport.
> >
> > All functions are empty stubs for now.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > Reviewed-by: Greg Kurz <groug@kaod.org>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 96 insertions(+)
> > create mode 100644 hw/9pfs/xen-9p-backend.c
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > new file mode 100644
> > index 0000000..35032d3
> > --- /dev/null
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -0,0 +1,96 @@
> > +/*
> > + * Xen 9p backend
> > + *
> > + * Copyright Aporeto 2017
> > + *
> > + * Authors:
> > + * Stefano Stabellini <stefano@aporeto.com>
> > + *
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +
> > +#include "hw/hw.h"
> > +#include "hw/9pfs/9p.h"
> > +#include "hw/xen/xen_backend.h"
> > +#include "xen_9pfs.h"
> > +#include "qemu/config-file.h"
> > +#include "fsdev/qemu-fsdev.h"
> > +
> > +typedef struct Xen9pfsDev {
> > + struct XenDevice xendev; /* must be first */
> > +} Xen9pfsDev;
> > +
> > +static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > + size_t offset,
> > + const char *fmt,
> > + va_list ap)
> > +{
> > + return 0;
> > +}
> > +
> > +static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> > + size_t offset,
> > + const char *fmt,
> > + va_list ap)
> > +{
> > + return 0;
> > +}
> > +
> > +static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> > + struct iovec **piov,
> > + unsigned int *pniov)
> > +{
> > +}
> > +
> > +static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> > + struct iovec **piov,
> > + unsigned int *pniov,
> > + size_t size)
> > +{
> > +}
> > +
> > +static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> > +{
> > +}
> > +
> > +static const struct V9fsTransport xen_9p_transport = {
> > + .pdu_vmarshal = xen_9pfs_pdu_vmarshal,
> > + .pdu_vunmarshal = xen_9pfs_pdu_vunmarshal,
> > + .init_in_iov_from_pdu = xen_9pfs_init_in_iov_from_pdu,
> > + .init_out_iov_from_pdu = xen_9pfs_init_out_iov_from_pdu,
> > + .push_and_notify = xen_9pfs_push_and_notify,
> > +};
> > +
> > +static int xen_9pfs_init(struct XenDevice *xendev)
> > +{
> > + return 0;
> > +}
> > +
> > +static int xen_9pfs_free(struct XenDevice *xendev)
> > +{
> > + return -1;
> > +}
> > +
> > +static int xen_9pfs_connect(struct XenDevice *xendev)
> > +{
> > + return 0;
> > +}
> > +
> > +static void xen_9pfs_alloc(struct XenDevice *xendev)
> > +{
> > +}
> > +
> > +static void xen_9pfs_disconnect(struct XenDevice *xendev)
> > +{
> > +}
> > +
> > +struct XenDevOps xen_9pfs_ops = {
> > + .size = sizeof(Xen9pfsDev),
> > + .flags = DEVOPS_FLAG_NEED_GNTDEV,
> > + .alloc = xen_9pfs_alloc,
> > + .init = xen_9pfs_init,
> > + .initialise = xen_9pfs_connect,
>
> Alignment?
I'll fix, thanks
> > + .disconnect = xen_9pfs_disconnect,
> > + .free = xen_9pfs_free,
> > +};
> >
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 4/9] xen/9pfs: introduce Xen 9pfs backend
@ 2017-03-14 20:07 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 20:07 UTC (permalink / raw)
To: Juergen Gross
Cc: Stefano Stabellini, qemu-devel, groug, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Tue, 14 Mar 2017, Juergen Gross wrote:
> On 14/03/17 00:55, Stefano Stabellini wrote:
> > Introduce the Xen 9pfs backend: add struct XenDevOps to register as a
> > Xen backend and add struct V9fsTransport to register as v9fs transport.
> >
> > All functions are empty stubs for now.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > Reviewed-by: Greg Kurz <groug@kaod.org>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 96 ++++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 96 insertions(+)
> > create mode 100644 hw/9pfs/xen-9p-backend.c
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > new file mode 100644
> > index 0000000..35032d3
> > --- /dev/null
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -0,0 +1,96 @@
> > +/*
> > + * Xen 9p backend
> > + *
> > + * Copyright Aporeto 2017
> > + *
> > + * Authors:
> > + * Stefano Stabellini <stefano@aporeto.com>
> > + *
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +
> > +#include "hw/hw.h"
> > +#include "hw/9pfs/9p.h"
> > +#include "hw/xen/xen_backend.h"
> > +#include "xen_9pfs.h"
> > +#include "qemu/config-file.h"
> > +#include "fsdev/qemu-fsdev.h"
> > +
> > +typedef struct Xen9pfsDev {
> > + struct XenDevice xendev; /* must be first */
> > +} Xen9pfsDev;
> > +
> > +static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > + size_t offset,
> > + const char *fmt,
> > + va_list ap)
> > +{
> > + return 0;
> > +}
> > +
> > +static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> > + size_t offset,
> > + const char *fmt,
> > + va_list ap)
> > +{
> > + return 0;
> > +}
> > +
> > +static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> > + struct iovec **piov,
> > + unsigned int *pniov)
> > +{
> > +}
> > +
> > +static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> > + struct iovec **piov,
> > + unsigned int *pniov,
> > + size_t size)
> > +{
> > +}
> > +
> > +static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> > +{
> > +}
> > +
> > +static const struct V9fsTransport xen_9p_transport = {
> > + .pdu_vmarshal = xen_9pfs_pdu_vmarshal,
> > + .pdu_vunmarshal = xen_9pfs_pdu_vunmarshal,
> > + .init_in_iov_from_pdu = xen_9pfs_init_in_iov_from_pdu,
> > + .init_out_iov_from_pdu = xen_9pfs_init_out_iov_from_pdu,
> > + .push_and_notify = xen_9pfs_push_and_notify,
> > +};
> > +
> > +static int xen_9pfs_init(struct XenDevice *xendev)
> > +{
> > + return 0;
> > +}
> > +
> > +static int xen_9pfs_free(struct XenDevice *xendev)
> > +{
> > + return -1;
> > +}
> > +
> > +static int xen_9pfs_connect(struct XenDevice *xendev)
> > +{
> > + return 0;
> > +}
> > +
> > +static void xen_9pfs_alloc(struct XenDevice *xendev)
> > +{
> > +}
> > +
> > +static void xen_9pfs_disconnect(struct XenDevice *xendev)
> > +{
> > +}
> > +
> > +struct XenDevOps xen_9pfs_ops = {
> > + .size = sizeof(Xen9pfsDev),
> > + .flags = DEVOPS_FLAG_NEED_GNTDEV,
> > + .alloc = xen_9pfs_alloc,
> > + .init = xen_9pfs_init,
> > + .initialise = xen_9pfs_connect,
>
> Alignment?
I'll fix, thanks
> > + .disconnect = xen_9pfs_disconnect,
> > + .free = xen_9pfs_free,
> > +};
> >
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* [Qemu-devel] [PATCH v2 5/9] xen/9pfs: connect to the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:55 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross, Aneesh Kumar K.V
Write the limits of the backend to xenstore. Connect to the frontend.
Upon connection, allocate the rings according to the protocol
specification.
Initialize a QEMUBH to schedule work upon receiving an event channel
notification from the frontend.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 158 insertions(+), 1 deletion(-)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 35032d3..0e4a133 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -17,8 +17,35 @@
#include "qemu/config-file.h"
#include "fsdev/qemu-fsdev.h"
+#define VERSIONS "1"
+#define MAX_RINGS 8
+#define MAX_RING_ORDER 8
+
+struct Xen9pfsRing {
+ struct Xen9pfsDev *priv;
+
+ int ref;
+ xenevtchn_handle *evtchndev;
+ int evtchn;
+ int local_port;
+ struct xen_9pfs_data_intf *intf;
+ unsigned char *data;
+ struct xen_9pfs_data ring;
+
+ QEMUBH *bh;
+
+ /* local copies, so that we can read/write PDU data directly from
+ * the ring */
+ RING_IDX out_cons, out_size, in_cons;
+ bool inprogress;
+};
+
typedef struct Xen9pfsDev {
struct XenDevice xendev; /* must be first */
+ V9fsState state;
+
+ int num_rings;
+ struct Xen9pfsRing *rings;
} Xen9pfsDev;
static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
@@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
return 0;
}
+static void xen_9pfs_bh(void *opaque)
+{
+}
+
+static void xen_9pfs_evtchn_event(void *opaque)
+{
+}
+
static int xen_9pfs_free(struct XenDevice *xendev)
{
- return -1;
+ int i;
+ struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
+
+ for (i = 0; i < xen_9pdev->num_rings; i++) {
+ if (xen_9pdev->rings[i].data != NULL) {
+ xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
+ xen_9pdev->rings[i].data,
+ (1 << XEN_9PFS_RING_ORDER));
+ }
+ if (xen_9pdev->rings[i].intf != NULL) {
+ xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
+ xen_9pdev->rings[i].intf,
+ 1);
+ }
+ if (xen_9pdev->rings[i].evtchndev > 0) {
+ qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
+ NULL, NULL, NULL);
+ xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
+ }
+ if (xen_9pdev->rings[i].bh != NULL) {
+ qemu_bh_delete(xen_9pdev->rings[i].bh);
+ }
+ }
+ g_free(xen_9pdev->rings);
+ return 0;
}
static int xen_9pfs_connect(struct XenDevice *xendev)
{
+ int i;
+ struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
+ V9fsState *s = &xen_9pdev->state;
+ QemuOpts *fsdev;
+ char *security_model, *path;
+
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
+ &xen_9pdev->num_rings) == -1 ||
+ xen_9pdev->num_rings > MAX_RINGS) {
+ return -1;
+ }
+
+ xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
+ for (i = 0; i < xen_9pdev->num_rings; i++) {
+ char str[16];
+
+ xen_9pdev->rings[i].priv = xen_9pdev;
+ xen_9pdev->rings[i].evtchn = -1;
+ xen_9pdev->rings[i].local_port = -1;
+
+ sprintf(str, "ring-ref%u", i);
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
+ &xen_9pdev->rings[i].ref) == -1) {
+ goto out;
+ }
+ sprintf(str, "event-channel-%u", i);
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
+ &xen_9pdev->rings[i].evtchn) == -1) {
+ goto out;
+ }
+
+ xen_9pdev->rings[i].intf = xengnttab_map_grant_ref(
+ xen_9pdev->xendev.gnttabdev,
+ xen_9pdev->xendev.dom,
+ xen_9pdev->rings[i].ref,
+ PROT_READ | PROT_WRITE);
+ if (!xen_9pdev->rings[i].intf) {
+ goto out;
+ }
+ xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
+ xen_9pdev->xendev.gnttabdev,
+ (1 << XEN_9PFS_RING_ORDER),
+ xen_9pdev->xendev.dom,
+ xen_9pdev->rings[i].intf->ref,
+ PROT_READ | PROT_WRITE);
+ if (!xen_9pdev->rings[i].data) {
+ goto out;
+ }
+ xen_9pdev->rings[i].ring.in = xen_9pdev->rings[i].data;
+ xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data + XEN_9PFS_RING_SIZE;
+
+ xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]);
+ xen_9pdev->rings[i].out_cons = 0;
+ xen_9pdev->rings[i].out_size = 0;
+ xen_9pdev->rings[i].inprogress = false;
+
+
+ xen_9pdev->rings[i].evtchndev = xenevtchn_open(NULL, 0);
+ if (xen_9pdev->rings[i].evtchndev == NULL) {
+ goto out;
+ }
+ fcntl(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), F_SETFD, FD_CLOEXEC);
+ xen_9pdev->rings[i].local_port = xenevtchn_bind_interdomain
+ (xen_9pdev->rings[i].evtchndev, xendev->dom, xen_9pdev->rings[i].evtchn);
+ if (xen_9pdev->rings[i].local_port == -1) {
+ xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed port=%d\n",
+ xen_9pdev->rings[i].evtchn);
+ goto out;
+ }
+ xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
+ qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
+ xen_9pfs_evtchn_event, NULL, &xen_9pdev->rings[i]);
+ }
+
+ security_model = xenstore_read_be_str(xendev, "security_model");
+ path = xenstore_read_be_str(xendev, "path");
+ s->fsconf.fsdev_id = g_malloc(strlen("xen9p") + 6);
+ sprintf(s->fsconf.fsdev_id, "xen9p%d", xendev->dev);
+ s->fsconf.tag = xenstore_read_fe_str(xendev, "tag");
+ v9fs_register_transport(s, &xen_9p_transport);
+ fsdev = qemu_opts_create(qemu_find_opts("fsdev"),
+ s->fsconf.tag,
+ 1, NULL);
+ qemu_opt_set(fsdev, "fsdriver", "local", NULL);
+ qemu_opt_set(fsdev, "path", path, NULL);
+ qemu_opt_set(fsdev, "security_model", security_model, NULL);
+ qemu_opts_set_id(fsdev, s->fsconf.fsdev_id);
+ qemu_fsdev_add(fsdev);
+ v9fs_device_realize_common(s, NULL);
+
return 0;
+
+out:
+ xen_9pfs_free(xendev);
+ return -1;
}
static void xen_9pfs_alloc(struct XenDevice *xendev)
{
+ xenstore_write_be_str(xendev, "versions", VERSIONS);
+ xenstore_write_be_int(xendev, "max-rings", MAX_RINGS);
+ xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER);
}
static void xen_9pfs_disconnect(struct XenDevice *xendev)
{
+ /* Dynamic hotplug of PV filesystems at runtime is not supported. */
}
struct XenDevOps xen_9pfs_ops = {
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 5/9] xen/9pfs: connect to the frontend
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
Write the limits of the backend to xenstore. Connect to the frontend.
Upon connection, allocate the rings according to the protocol
specification.
Initialize a QEMUBH to schedule work upon receiving an event channel
notification from the frontend.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 158 insertions(+), 1 deletion(-)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 35032d3..0e4a133 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -17,8 +17,35 @@
#include "qemu/config-file.h"
#include "fsdev/qemu-fsdev.h"
+#define VERSIONS "1"
+#define MAX_RINGS 8
+#define MAX_RING_ORDER 8
+
+struct Xen9pfsRing {
+ struct Xen9pfsDev *priv;
+
+ int ref;
+ xenevtchn_handle *evtchndev;
+ int evtchn;
+ int local_port;
+ struct xen_9pfs_data_intf *intf;
+ unsigned char *data;
+ struct xen_9pfs_data ring;
+
+ QEMUBH *bh;
+
+ /* local copies, so that we can read/write PDU data directly from
+ * the ring */
+ RING_IDX out_cons, out_size, in_cons;
+ bool inprogress;
+};
+
typedef struct Xen9pfsDev {
struct XenDevice xendev; /* must be first */
+ V9fsState state;
+
+ int num_rings;
+ struct Xen9pfsRing *rings;
} Xen9pfsDev;
static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
@@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
return 0;
}
+static void xen_9pfs_bh(void *opaque)
+{
+}
+
+static void xen_9pfs_evtchn_event(void *opaque)
+{
+}
+
static int xen_9pfs_free(struct XenDevice *xendev)
{
- return -1;
+ int i;
+ struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
+
+ for (i = 0; i < xen_9pdev->num_rings; i++) {
+ if (xen_9pdev->rings[i].data != NULL) {
+ xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
+ xen_9pdev->rings[i].data,
+ (1 << XEN_9PFS_RING_ORDER));
+ }
+ if (xen_9pdev->rings[i].intf != NULL) {
+ xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
+ xen_9pdev->rings[i].intf,
+ 1);
+ }
+ if (xen_9pdev->rings[i].evtchndev > 0) {
+ qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
+ NULL, NULL, NULL);
+ xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
+ }
+ if (xen_9pdev->rings[i].bh != NULL) {
+ qemu_bh_delete(xen_9pdev->rings[i].bh);
+ }
+ }
+ g_free(xen_9pdev->rings);
+ return 0;
}
static int xen_9pfs_connect(struct XenDevice *xendev)
{
+ int i;
+ struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
+ V9fsState *s = &xen_9pdev->state;
+ QemuOpts *fsdev;
+ char *security_model, *path;
+
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
+ &xen_9pdev->num_rings) == -1 ||
+ xen_9pdev->num_rings > MAX_RINGS) {
+ return -1;
+ }
+
+ xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
+ for (i = 0; i < xen_9pdev->num_rings; i++) {
+ char str[16];
+
+ xen_9pdev->rings[i].priv = xen_9pdev;
+ xen_9pdev->rings[i].evtchn = -1;
+ xen_9pdev->rings[i].local_port = -1;
+
+ sprintf(str, "ring-ref%u", i);
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
+ &xen_9pdev->rings[i].ref) == -1) {
+ goto out;
+ }
+ sprintf(str, "event-channel-%u", i);
+ if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
+ &xen_9pdev->rings[i].evtchn) == -1) {
+ goto out;
+ }
+
+ xen_9pdev->rings[i].intf = xengnttab_map_grant_ref(
+ xen_9pdev->xendev.gnttabdev,
+ xen_9pdev->xendev.dom,
+ xen_9pdev->rings[i].ref,
+ PROT_READ | PROT_WRITE);
+ if (!xen_9pdev->rings[i].intf) {
+ goto out;
+ }
+ xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
+ xen_9pdev->xendev.gnttabdev,
+ (1 << XEN_9PFS_RING_ORDER),
+ xen_9pdev->xendev.dom,
+ xen_9pdev->rings[i].intf->ref,
+ PROT_READ | PROT_WRITE);
+ if (!xen_9pdev->rings[i].data) {
+ goto out;
+ }
+ xen_9pdev->rings[i].ring.in = xen_9pdev->rings[i].data;
+ xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data + XEN_9PFS_RING_SIZE;
+
+ xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]);
+ xen_9pdev->rings[i].out_cons = 0;
+ xen_9pdev->rings[i].out_size = 0;
+ xen_9pdev->rings[i].inprogress = false;
+
+
+ xen_9pdev->rings[i].evtchndev = xenevtchn_open(NULL, 0);
+ if (xen_9pdev->rings[i].evtchndev == NULL) {
+ goto out;
+ }
+ fcntl(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), F_SETFD, FD_CLOEXEC);
+ xen_9pdev->rings[i].local_port = xenevtchn_bind_interdomain
+ (xen_9pdev->rings[i].evtchndev, xendev->dom, xen_9pdev->rings[i].evtchn);
+ if (xen_9pdev->rings[i].local_port == -1) {
+ xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed port=%d\n",
+ xen_9pdev->rings[i].evtchn);
+ goto out;
+ }
+ xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
+ qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
+ xen_9pfs_evtchn_event, NULL, &xen_9pdev->rings[i]);
+ }
+
+ security_model = xenstore_read_be_str(xendev, "security_model");
+ path = xenstore_read_be_str(xendev, "path");
+ s->fsconf.fsdev_id = g_malloc(strlen("xen9p") + 6);
+ sprintf(s->fsconf.fsdev_id, "xen9p%d", xendev->dev);
+ s->fsconf.tag = xenstore_read_fe_str(xendev, "tag");
+ v9fs_register_transport(s, &xen_9p_transport);
+ fsdev = qemu_opts_create(qemu_find_opts("fsdev"),
+ s->fsconf.tag,
+ 1, NULL);
+ qemu_opt_set(fsdev, "fsdriver", "local", NULL);
+ qemu_opt_set(fsdev, "path", path, NULL);
+ qemu_opt_set(fsdev, "security_model", security_model, NULL);
+ qemu_opts_set_id(fsdev, s->fsconf.fsdev_id);
+ qemu_fsdev_add(fsdev);
+ v9fs_device_realize_common(s, NULL);
+
return 0;
+
+out:
+ xen_9pfs_free(xendev);
+ return -1;
}
static void xen_9pfs_alloc(struct XenDevice *xendev)
{
+ xenstore_write_be_str(xendev, "versions", VERSIONS);
+ xenstore_write_be_int(xendev, "max-rings", MAX_RINGS);
+ xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER);
}
static void xen_9pfs_disconnect(struct XenDevice *xendev)
{
+ /* Dynamic hotplug of PV filesystems at runtime is not supported. */
}
struct XenDevOps xen_9pfs_ops = {
--
1.9.1
_______________________________________________
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Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 5/9] xen/9pfs: connect to the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-14 7:17 ` Juergen Gross
-1 siblings, 0 replies; 72+ messages in thread
From: Juergen Gross @ 2017-03-14 7:17 UTC (permalink / raw)
To: Stefano Stabellini, qemu-devel
Cc: xen-devel, anthony.perard, groug, Stefano Stabellini, Aneesh Kumar K.V
On 14/03/17 00:55, Stefano Stabellini wrote:
> Write the limits of the backend to xenstore. Connect to the frontend.
> Upon connection, allocate the rings according to the protocol
> specification.
>
> Initialize a QEMUBH to schedule work upon receiving an event channel
> notification from the frontend.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 158 insertions(+), 1 deletion(-)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 35032d3..0e4a133 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -17,8 +17,35 @@
> #include "qemu/config-file.h"
> #include "fsdev/qemu-fsdev.h"
>
> +#define VERSIONS "1"
> +#define MAX_RINGS 8
> +#define MAX_RING_ORDER 8
> +
> +struct Xen9pfsRing {
> + struct Xen9pfsDev *priv;
> +
> + int ref;
> + xenevtchn_handle *evtchndev;
> + int evtchn;
> + int local_port;
> + struct xen_9pfs_data_intf *intf;
> + unsigned char *data;
> + struct xen_9pfs_data ring;
> +
> + QEMUBH *bh;
> +
> + /* local copies, so that we can read/write PDU data directly from
> + * the ring */
> + RING_IDX out_cons, out_size, in_cons;
> + bool inprogress;
> +};
> +
> typedef struct Xen9pfsDev {
> struct XenDevice xendev; /* must be first */
> + V9fsState state;
> +
> + int num_rings;
> + struct Xen9pfsRing *rings;
> } Xen9pfsDev;
>
> static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static void xen_9pfs_bh(void *opaque)
> +{
> +}
> +
> +static void xen_9pfs_evtchn_event(void *opaque)
> +{
> +}
> +
> static int xen_9pfs_free(struct XenDevice *xendev)
> {
> - return -1;
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> +
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + if (xen_9pdev->rings[i].data != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].data,
> + (1 << XEN_9PFS_RING_ORDER));
> + }
> + if (xen_9pdev->rings[i].intf != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].intf,
> + 1);
> + }
> + if (xen_9pdev->rings[i].evtchndev > 0) {
> + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> + NULL, NULL, NULL);
> + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> + }
> + if (xen_9pdev->rings[i].bh != NULL) {
> + qemu_bh_delete(xen_9pdev->rings[i].bh);
> + }
> + }
> + g_free(xen_9pdev->rings);
> + return 0;
> }
>
> static int xen_9pfs_connect(struct XenDevice *xendev)
> {
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> + V9fsState *s = &xen_9pdev->state;
> + QemuOpts *fsdev;
> + char *security_model, *path;
> +
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> + &xen_9pdev->num_rings) == -1 ||
> + xen_9pdev->num_rings > MAX_RINGS) {
What if num_rings is < 1?
> + return -1;
> + }
> +
> + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + char str[16];
> +
> + xen_9pdev->rings[i].priv = xen_9pdev;
> + xen_9pdev->rings[i].evtchn = -1;
> + xen_9pdev->rings[i].local_port = -1;
> +
> + sprintf(str, "ring-ref%u", i);
use g_strdup_printf()?
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> + &xen_9pdev->rings[i].ref) == -1) {
> + goto out;
> + }
> + sprintf(str, "event-channel-%u", i);
use g_strdup_printf()?
Juergen
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 5/9] xen/9pfs: connect to the frontend
@ 2017-03-14 7:17 ` Juergen Gross
0 siblings, 0 replies; 72+ messages in thread
From: Juergen Gross @ 2017-03-14 7:17 UTC (permalink / raw)
To: Stefano Stabellini, qemu-devel
Cc: anthony.perard, xen-devel, Stefano Stabellini, groug, Aneesh Kumar K.V
On 14/03/17 00:55, Stefano Stabellini wrote:
> Write the limits of the backend to xenstore. Connect to the frontend.
> Upon connection, allocate the rings according to the protocol
> specification.
>
> Initialize a QEMUBH to schedule work upon receiving an event channel
> notification from the frontend.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 158 insertions(+), 1 deletion(-)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 35032d3..0e4a133 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -17,8 +17,35 @@
> #include "qemu/config-file.h"
> #include "fsdev/qemu-fsdev.h"
>
> +#define VERSIONS "1"
> +#define MAX_RINGS 8
> +#define MAX_RING_ORDER 8
> +
> +struct Xen9pfsRing {
> + struct Xen9pfsDev *priv;
> +
> + int ref;
> + xenevtchn_handle *evtchndev;
> + int evtchn;
> + int local_port;
> + struct xen_9pfs_data_intf *intf;
> + unsigned char *data;
> + struct xen_9pfs_data ring;
> +
> + QEMUBH *bh;
> +
> + /* local copies, so that we can read/write PDU data directly from
> + * the ring */
> + RING_IDX out_cons, out_size, in_cons;
> + bool inprogress;
> +};
> +
> typedef struct Xen9pfsDev {
> struct XenDevice xendev; /* must be first */
> + V9fsState state;
> +
> + int num_rings;
> + struct Xen9pfsRing *rings;
> } Xen9pfsDev;
>
> static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static void xen_9pfs_bh(void *opaque)
> +{
> +}
> +
> +static void xen_9pfs_evtchn_event(void *opaque)
> +{
> +}
> +
> static int xen_9pfs_free(struct XenDevice *xendev)
> {
> - return -1;
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> +
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + if (xen_9pdev->rings[i].data != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].data,
> + (1 << XEN_9PFS_RING_ORDER));
> + }
> + if (xen_9pdev->rings[i].intf != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].intf,
> + 1);
> + }
> + if (xen_9pdev->rings[i].evtchndev > 0) {
> + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> + NULL, NULL, NULL);
> + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> + }
> + if (xen_9pdev->rings[i].bh != NULL) {
> + qemu_bh_delete(xen_9pdev->rings[i].bh);
> + }
> + }
> + g_free(xen_9pdev->rings);
> + return 0;
> }
>
> static int xen_9pfs_connect(struct XenDevice *xendev)
> {
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> + V9fsState *s = &xen_9pdev->state;
> + QemuOpts *fsdev;
> + char *security_model, *path;
> +
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> + &xen_9pdev->num_rings) == -1 ||
> + xen_9pdev->num_rings > MAX_RINGS) {
What if num_rings is < 1?
> + return -1;
> + }
> +
> + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + char str[16];
> +
> + xen_9pdev->rings[i].priv = xen_9pdev;
> + xen_9pdev->rings[i].evtchn = -1;
> + xen_9pdev->rings[i].local_port = -1;
> +
> + sprintf(str, "ring-ref%u", i);
use g_strdup_printf()?
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> + &xen_9pdev->rings[i].ref) == -1) {
> + goto out;
> + }
> + sprintf(str, "event-channel-%u", i);
use g_strdup_printf()?
Juergen
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 5/9] xen/9pfs: connect to the frontend
2017-03-14 7:17 ` Juergen Gross
@ 2017-03-14 20:14 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 20:14 UTC (permalink / raw)
To: Juergen Gross
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard, groug,
Stefano Stabellini, Aneesh Kumar K.V
On Tue, 14 Mar 2017, Juergen Gross wrote:
> On 14/03/17 00:55, Stefano Stabellini wrote:
> > Write the limits of the backend to xenstore. Connect to the frontend.
> > Upon connection, allocate the rings according to the protocol
> > specification.
> >
> > Initialize a QEMUBH to schedule work upon receiving an event channel
> > notification from the frontend.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 158 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 35032d3..0e4a133 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -17,8 +17,35 @@
> > #include "qemu/config-file.h"
> > #include "fsdev/qemu-fsdev.h"
> >
> > +#define VERSIONS "1"
> > +#define MAX_RINGS 8
> > +#define MAX_RING_ORDER 8
> > +
> > +struct Xen9pfsRing {
> > + struct Xen9pfsDev *priv;
> > +
> > + int ref;
> > + xenevtchn_handle *evtchndev;
> > + int evtchn;
> > + int local_port;
> > + struct xen_9pfs_data_intf *intf;
> > + unsigned char *data;
> > + struct xen_9pfs_data ring;
> > +
> > + QEMUBH *bh;
> > +
> > + /* local copies, so that we can read/write PDU data directly from
> > + * the ring */
> > + RING_IDX out_cons, out_size, in_cons;
> > + bool inprogress;
> > +};
> > +
> > typedef struct Xen9pfsDev {
> > struct XenDevice xendev; /* must be first */
> > + V9fsState state;
> > +
> > + int num_rings;
> > + struct Xen9pfsRing *rings;
> > } Xen9pfsDev;
> >
> > static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static void xen_9pfs_bh(void *opaque)
> > +{
> > +}
> > +
> > +static void xen_9pfs_evtchn_event(void *opaque)
> > +{
> > +}
> > +
> > static int xen_9pfs_free(struct XenDevice *xendev)
> > {
> > - return -1;
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> > +
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + if (xen_9pdev->rings[i].data != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].data,
> > + (1 << XEN_9PFS_RING_ORDER));
> > + }
> > + if (xen_9pdev->rings[i].intf != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].intf,
> > + 1);
> > + }
> > + if (xen_9pdev->rings[i].evtchndev > 0) {
> > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> > + NULL, NULL, NULL);
> > + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> > + }
> > + if (xen_9pdev->rings[i].bh != NULL) {
> > + qemu_bh_delete(xen_9pdev->rings[i].bh);
> > + }
> > + }
> > + g_free(xen_9pdev->rings);
> > + return 0;
> > }
> >
> > static int xen_9pfs_connect(struct XenDevice *xendev)
> > {
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> > + V9fsState *s = &xen_9pdev->state;
> > + QemuOpts *fsdev;
> > + char *security_model, *path;
> > +
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> > + &xen_9pdev->num_rings) == -1 ||
> > + xen_9pdev->num_rings > MAX_RINGS) {
>
> What if num_rings is < 1?
Good point, I'll add a check for that
> > + return -1;
> > + }
> > +
> > + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + char str[16];
> > +
> > + xen_9pdev->rings[i].priv = xen_9pdev;
> > + xen_9pdev->rings[i].evtchn = -1;
> > + xen_9pdev->rings[i].local_port = -1;
> > +
> > + sprintf(str, "ring-ref%u", i);
>
> use g_strdup_printf()?
OK
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> > + &xen_9pdev->rings[i].ref) == -1) {
> > + goto out;
> > + }
> > + sprintf(str, "event-channel-%u", i);
>
> use g_strdup_printf()?
Sure
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 5/9] xen/9pfs: connect to the frontend
@ 2017-03-14 20:14 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 20:14 UTC (permalink / raw)
To: Juergen Gross
Cc: Stefano Stabellini, qemu-devel, groug, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Tue, 14 Mar 2017, Juergen Gross wrote:
> On 14/03/17 00:55, Stefano Stabellini wrote:
> > Write the limits of the backend to xenstore. Connect to the frontend.
> > Upon connection, allocate the rings according to the protocol
> > specification.
> >
> > Initialize a QEMUBH to schedule work upon receiving an event channel
> > notification from the frontend.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 158 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 35032d3..0e4a133 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -17,8 +17,35 @@
> > #include "qemu/config-file.h"
> > #include "fsdev/qemu-fsdev.h"
> >
> > +#define VERSIONS "1"
> > +#define MAX_RINGS 8
> > +#define MAX_RING_ORDER 8
> > +
> > +struct Xen9pfsRing {
> > + struct Xen9pfsDev *priv;
> > +
> > + int ref;
> > + xenevtchn_handle *evtchndev;
> > + int evtchn;
> > + int local_port;
> > + struct xen_9pfs_data_intf *intf;
> > + unsigned char *data;
> > + struct xen_9pfs_data ring;
> > +
> > + QEMUBH *bh;
> > +
> > + /* local copies, so that we can read/write PDU data directly from
> > + * the ring */
> > + RING_IDX out_cons, out_size, in_cons;
> > + bool inprogress;
> > +};
> > +
> > typedef struct Xen9pfsDev {
> > struct XenDevice xendev; /* must be first */
> > + V9fsState state;
> > +
> > + int num_rings;
> > + struct Xen9pfsRing *rings;
> > } Xen9pfsDev;
> >
> > static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static void xen_9pfs_bh(void *opaque)
> > +{
> > +}
> > +
> > +static void xen_9pfs_evtchn_event(void *opaque)
> > +{
> > +}
> > +
> > static int xen_9pfs_free(struct XenDevice *xendev)
> > {
> > - return -1;
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> > +
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + if (xen_9pdev->rings[i].data != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].data,
> > + (1 << XEN_9PFS_RING_ORDER));
> > + }
> > + if (xen_9pdev->rings[i].intf != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].intf,
> > + 1);
> > + }
> > + if (xen_9pdev->rings[i].evtchndev > 0) {
> > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> > + NULL, NULL, NULL);
> > + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> > + }
> > + if (xen_9pdev->rings[i].bh != NULL) {
> > + qemu_bh_delete(xen_9pdev->rings[i].bh);
> > + }
> > + }
> > + g_free(xen_9pdev->rings);
> > + return 0;
> > }
> >
> > static int xen_9pfs_connect(struct XenDevice *xendev)
> > {
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> > + V9fsState *s = &xen_9pdev->state;
> > + QemuOpts *fsdev;
> > + char *security_model, *path;
> > +
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> > + &xen_9pdev->num_rings) == -1 ||
> > + xen_9pdev->num_rings > MAX_RINGS) {
>
> What if num_rings is < 1?
Good point, I'll add a check for that
> > + return -1;
> > + }
> > +
> > + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + char str[16];
> > +
> > + xen_9pdev->rings[i].priv = xen_9pdev;
> > + xen_9pdev->rings[i].evtchn = -1;
> > + xen_9pdev->rings[i].local_port = -1;
> > +
> > + sprintf(str, "ring-ref%u", i);
>
> use g_strdup_printf()?
OK
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> > + &xen_9pdev->rings[i].ref) == -1) {
> > + goto out;
> > + }
> > + sprintf(str, "event-channel-%u", i);
>
> use g_strdup_printf()?
Sure
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
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^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 5/9] xen/9pfs: connect to the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-15 9:48 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 9:48 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini,
jgross, Aneesh Kumar K.V
[-- Attachment #1: Type: text/plain, Size: 8246 bytes --]
On Mon, 13 Mar 2017 16:55:56 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Write the limits of the backend to xenstore. Connect to the frontend.
> Upon connection, allocate the rings according to the protocol
> specification.
>
> Initialize a QEMUBH to schedule work upon receiving an event channel
> notification from the frontend.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 158 insertions(+), 1 deletion(-)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 35032d3..0e4a133 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -17,8 +17,35 @@
> #include "qemu/config-file.h"
> #include "fsdev/qemu-fsdev.h"
>
> +#define VERSIONS "1"
> +#define MAX_RINGS 8
> +#define MAX_RING_ORDER 8
> +
> +struct Xen9pfsRing {
> + struct Xen9pfsDev *priv;
> +
> + int ref;
> + xenevtchn_handle *evtchndev;
> + int evtchn;
> + int local_port;
> + struct xen_9pfs_data_intf *intf;
> + unsigned char *data;
> + struct xen_9pfs_data ring;
> +
> + QEMUBH *bh;
> +
> + /* local copies, so that we can read/write PDU data directly from
> + * the ring */
> + RING_IDX out_cons, out_size, in_cons;
> + bool inprogress;
> +};
> +
QEMU Coding style requires a typedef. FWIW, maybe you could also convert
other structured types like XenDevice or XenDevOps.
> typedef struct Xen9pfsDev {
> struct XenDevice xendev; /* must be first */
> + V9fsState state;
> +
> + int num_rings;
> + struct Xen9pfsRing *rings;
> } Xen9pfsDev;
>
> static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static void xen_9pfs_bh(void *opaque)
> +{
> +}
> +
> +static void xen_9pfs_evtchn_event(void *opaque)
> +{
> +}
> +
> static int xen_9pfs_free(struct XenDevice *xendev)
> {
> - return -1;
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> +
Coding style.
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + if (xen_9pdev->rings[i].data != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].data,
> + (1 << XEN_9PFS_RING_ORDER));
> + }
> + if (xen_9pdev->rings[i].intf != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].intf,
> + 1);
> + }
> + if (xen_9pdev->rings[i].evtchndev > 0) {
> + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> + NULL, NULL, NULL);
> + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> + }
> + if (xen_9pdev->rings[i].bh != NULL) {
> + qemu_bh_delete(xen_9pdev->rings[i].bh);
> + }
> + }
> + g_free(xen_9pdev->rings);
> + return 0;
> }
>
> static int xen_9pfs_connect(struct XenDevice *xendev)
> {
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
Coding style.
> + V9fsState *s = &xen_9pdev->state;
> + QemuOpts *fsdev;
> + char *security_model, *path;
> +
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> + &xen_9pdev->num_rings) == -1 ||
> + xen_9pdev->num_rings > MAX_RINGS) {
> + return -1;
> + }
> +
> + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + char str[16];
> +
> + xen_9pdev->rings[i].priv = xen_9pdev;
> + xen_9pdev->rings[i].evtchn = -1;
> + xen_9pdev->rings[i].local_port = -1;
> +
> + sprintf(str, "ring-ref%u", i);
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> + &xen_9pdev->rings[i].ref) == -1) {
> + goto out;
> + }
> + sprintf(str, "event-channel-%u", i);
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> + &xen_9pdev->rings[i].evtchn) == -1) {
> + goto out;
> + }
> +
> + xen_9pdev->rings[i].intf = xengnttab_map_grant_ref(
> + xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->xendev.dom,
> + xen_9pdev->rings[i].ref,
> + PROT_READ | PROT_WRITE);
> + if (!xen_9pdev->rings[i].intf) {
> + goto out;
> + }
> + xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
> + xen_9pdev->xendev.gnttabdev,
> + (1 << XEN_9PFS_RING_ORDER),
> + xen_9pdev->xendev.dom,
> + xen_9pdev->rings[i].intf->ref,
> + PROT_READ | PROT_WRITE);
> + if (!xen_9pdev->rings[i].data) {
> + goto out;
> + }
> + xen_9pdev->rings[i].ring.in = xen_9pdev->rings[i].data;
> + xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data + XEN_9PFS_RING_SIZE;
> +
> + xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]);
> + xen_9pdev->rings[i].out_cons = 0;
> + xen_9pdev->rings[i].out_size = 0;
> + xen_9pdev->rings[i].inprogress = false;
> +
> +
> + xen_9pdev->rings[i].evtchndev = xenevtchn_open(NULL, 0);
> + if (xen_9pdev->rings[i].evtchndev == NULL) {
> + goto out;
> + }
> + fcntl(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), F_SETFD, FD_CLOEXEC);
> + xen_9pdev->rings[i].local_port = xenevtchn_bind_interdomain
> + (xen_9pdev->rings[i].evtchndev, xendev->dom, xen_9pdev->rings[i].evtchn);
> + if (xen_9pdev->rings[i].local_port == -1) {
> + xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed port=%d\n",
> + xen_9pdev->rings[i].evtchn);
> + goto out;
> + }
> + xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
> + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> + xen_9pfs_evtchn_event, NULL, &xen_9pdev->rings[i]);
> + }
> +
> + security_model = xenstore_read_be_str(xendev, "security_model");
> + path = xenstore_read_be_str(xendev, "path");
> + s->fsconf.fsdev_id = g_malloc(strlen("xen9p") + 6);
> + sprintf(s->fsconf.fsdev_id, "xen9p%d", xendev->dev);
Please use g_strdup_printf().
> + s->fsconf.tag = xenstore_read_fe_str(xendev, "tag");
> + v9fs_register_transport(s, &xen_9p_transport);
> + fsdev = qemu_opts_create(qemu_find_opts("fsdev"),
> + s->fsconf.tag,
> + 1, NULL);
> + qemu_opt_set(fsdev, "fsdriver", "local", NULL);
> + qemu_opt_set(fsdev, "path", path, NULL);
> + qemu_opt_set(fsdev, "security_model", security_model, NULL);
> + qemu_opts_set_id(fsdev, s->fsconf.fsdev_id);
> + qemu_fsdev_add(fsdev);
> + v9fs_device_realize_common(s, NULL);
> +
> return 0;
> +
> +out:
> + xen_9pfs_free(xendev);
> + return -1;
> }
>
> static void xen_9pfs_alloc(struct XenDevice *xendev)
> {
> + xenstore_write_be_str(xendev, "versions", VERSIONS);
> + xenstore_write_be_int(xendev, "max-rings", MAX_RINGS);
> + xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER);
> }
>
> static void xen_9pfs_disconnect(struct XenDevice *xendev)
> {
> + /* Dynamic hotplug of PV filesystems at runtime is not supported. */
Does this mean that this function is never called ? Or that it should
report an error ? Or print one ?
In any case, it looks weird that it doesn't free the fsdev_id that
was allocated in xen_9pfs_connect().
> }
>
> struct XenDevOps xen_9pfs_ops = {
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 5/9] xen/9pfs: connect to the frontend
@ 2017-03-15 9:48 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 9:48 UTC (permalink / raw)
To: Stefano Stabellini
Cc: jgross, qemu-devel, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
[-- Attachment #1.1: Type: text/plain, Size: 8246 bytes --]
On Mon, 13 Mar 2017 16:55:56 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Write the limits of the backend to xenstore. Connect to the frontend.
> Upon connection, allocate the rings according to the protocol
> specification.
>
> Initialize a QEMUBH to schedule work upon receiving an event channel
> notification from the frontend.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 158 insertions(+), 1 deletion(-)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 35032d3..0e4a133 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -17,8 +17,35 @@
> #include "qemu/config-file.h"
> #include "fsdev/qemu-fsdev.h"
>
> +#define VERSIONS "1"
> +#define MAX_RINGS 8
> +#define MAX_RING_ORDER 8
> +
> +struct Xen9pfsRing {
> + struct Xen9pfsDev *priv;
> +
> + int ref;
> + xenevtchn_handle *evtchndev;
> + int evtchn;
> + int local_port;
> + struct xen_9pfs_data_intf *intf;
> + unsigned char *data;
> + struct xen_9pfs_data ring;
> +
> + QEMUBH *bh;
> +
> + /* local copies, so that we can read/write PDU data directly from
> + * the ring */
> + RING_IDX out_cons, out_size, in_cons;
> + bool inprogress;
> +};
> +
QEMU Coding style requires a typedef. FWIW, maybe you could also convert
other structured types like XenDevice or XenDevOps.
> typedef struct Xen9pfsDev {
> struct XenDevice xendev; /* must be first */
> + V9fsState state;
> +
> + int num_rings;
> + struct Xen9pfsRing *rings;
> } Xen9pfsDev;
>
> static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static void xen_9pfs_bh(void *opaque)
> +{
> +}
> +
> +static void xen_9pfs_evtchn_event(void *opaque)
> +{
> +}
> +
> static int xen_9pfs_free(struct XenDevice *xendev)
> {
> - return -1;
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> +
Coding style.
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + if (xen_9pdev->rings[i].data != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].data,
> + (1 << XEN_9PFS_RING_ORDER));
> + }
> + if (xen_9pdev->rings[i].intf != NULL) {
> + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->rings[i].intf,
> + 1);
> + }
> + if (xen_9pdev->rings[i].evtchndev > 0) {
> + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> + NULL, NULL, NULL);
> + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> + }
> + if (xen_9pdev->rings[i].bh != NULL) {
> + qemu_bh_delete(xen_9pdev->rings[i].bh);
> + }
> + }
> + g_free(xen_9pdev->rings);
> + return 0;
> }
>
> static int xen_9pfs_connect(struct XenDevice *xendev)
> {
> + int i;
> + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
Coding style.
> + V9fsState *s = &xen_9pdev->state;
> + QemuOpts *fsdev;
> + char *security_model, *path;
> +
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> + &xen_9pdev->num_rings) == -1 ||
> + xen_9pdev->num_rings > MAX_RINGS) {
> + return -1;
> + }
> +
> + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> + for (i = 0; i < xen_9pdev->num_rings; i++) {
> + char str[16];
> +
> + xen_9pdev->rings[i].priv = xen_9pdev;
> + xen_9pdev->rings[i].evtchn = -1;
> + xen_9pdev->rings[i].local_port = -1;
> +
> + sprintf(str, "ring-ref%u", i);
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> + &xen_9pdev->rings[i].ref) == -1) {
> + goto out;
> + }
> + sprintf(str, "event-channel-%u", i);
> + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> + &xen_9pdev->rings[i].evtchn) == -1) {
> + goto out;
> + }
> +
> + xen_9pdev->rings[i].intf = xengnttab_map_grant_ref(
> + xen_9pdev->xendev.gnttabdev,
> + xen_9pdev->xendev.dom,
> + xen_9pdev->rings[i].ref,
> + PROT_READ | PROT_WRITE);
> + if (!xen_9pdev->rings[i].intf) {
> + goto out;
> + }
> + xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
> + xen_9pdev->xendev.gnttabdev,
> + (1 << XEN_9PFS_RING_ORDER),
> + xen_9pdev->xendev.dom,
> + xen_9pdev->rings[i].intf->ref,
> + PROT_READ | PROT_WRITE);
> + if (!xen_9pdev->rings[i].data) {
> + goto out;
> + }
> + xen_9pdev->rings[i].ring.in = xen_9pdev->rings[i].data;
> + xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data + XEN_9PFS_RING_SIZE;
> +
> + xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]);
> + xen_9pdev->rings[i].out_cons = 0;
> + xen_9pdev->rings[i].out_size = 0;
> + xen_9pdev->rings[i].inprogress = false;
> +
> +
> + xen_9pdev->rings[i].evtchndev = xenevtchn_open(NULL, 0);
> + if (xen_9pdev->rings[i].evtchndev == NULL) {
> + goto out;
> + }
> + fcntl(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), F_SETFD, FD_CLOEXEC);
> + xen_9pdev->rings[i].local_port = xenevtchn_bind_interdomain
> + (xen_9pdev->rings[i].evtchndev, xendev->dom, xen_9pdev->rings[i].evtchn);
> + if (xen_9pdev->rings[i].local_port == -1) {
> + xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed port=%d\n",
> + xen_9pdev->rings[i].evtchn);
> + goto out;
> + }
> + xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
> + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> + xen_9pfs_evtchn_event, NULL, &xen_9pdev->rings[i]);
> + }
> +
> + security_model = xenstore_read_be_str(xendev, "security_model");
> + path = xenstore_read_be_str(xendev, "path");
> + s->fsconf.fsdev_id = g_malloc(strlen("xen9p") + 6);
> + sprintf(s->fsconf.fsdev_id, "xen9p%d", xendev->dev);
Please use g_strdup_printf().
> + s->fsconf.tag = xenstore_read_fe_str(xendev, "tag");
> + v9fs_register_transport(s, &xen_9p_transport);
> + fsdev = qemu_opts_create(qemu_find_opts("fsdev"),
> + s->fsconf.tag,
> + 1, NULL);
> + qemu_opt_set(fsdev, "fsdriver", "local", NULL);
> + qemu_opt_set(fsdev, "path", path, NULL);
> + qemu_opt_set(fsdev, "security_model", security_model, NULL);
> + qemu_opts_set_id(fsdev, s->fsconf.fsdev_id);
> + qemu_fsdev_add(fsdev);
> + v9fs_device_realize_common(s, NULL);
> +
> return 0;
> +
> +out:
> + xen_9pfs_free(xendev);
> + return -1;
> }
>
> static void xen_9pfs_alloc(struct XenDevice *xendev)
> {
> + xenstore_write_be_str(xendev, "versions", VERSIONS);
> + xenstore_write_be_int(xendev, "max-rings", MAX_RINGS);
> + xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER);
> }
>
> static void xen_9pfs_disconnect(struct XenDevice *xendev)
> {
> + /* Dynamic hotplug of PV filesystems at runtime is not supported. */
Does this mean that this function is never called ? Or that it should
report an error ? Or print one ?
In any case, it looks weird that it doesn't free the fsdev_id that
was allocated in xen_9pfs_connect().
> }
>
> struct XenDevOps xen_9pfs_ops = {
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 5/9] xen/9pfs: connect to the frontend
2017-03-15 9:48 ` Greg Kurz
@ 2017-03-15 21:30 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:30 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard,
Stefano Stabellini, jgross, Aneesh Kumar K.V
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:56 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Write the limits of the backend to xenstore. Connect to the frontend.
> > Upon connection, allocate the rings according to the protocol
> > specification.
> >
> > Initialize a QEMUBH to schedule work upon receiving an event channel
> > notification from the frontend.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 158 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 35032d3..0e4a133 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -17,8 +17,35 @@
> > #include "qemu/config-file.h"
> > #include "fsdev/qemu-fsdev.h"
> >
> > +#define VERSIONS "1"
> > +#define MAX_RINGS 8
> > +#define MAX_RING_ORDER 8
> > +
> > +struct Xen9pfsRing {
> > + struct Xen9pfsDev *priv;
> > +
> > + int ref;
> > + xenevtchn_handle *evtchndev;
> > + int evtchn;
> > + int local_port;
> > + struct xen_9pfs_data_intf *intf;
> > + unsigned char *data;
> > + struct xen_9pfs_data ring;
> > +
> > + QEMUBH *bh;
> > +
> > + /* local copies, so that we can read/write PDU data directly from
> > + * the ring */
> > + RING_IDX out_cons, out_size, in_cons;
> > + bool inprogress;
> > +};
> > +
>
> QEMU Coding style requires a typedef.
OK
> FWIW, maybe you could also convert
> other structured types like XenDevice or XenDevOps.
I'll do in a separate series
> > typedef struct Xen9pfsDev {
> > struct XenDevice xendev; /* must be first */
> > + V9fsState state;
> > +
> > + int num_rings;
> > + struct Xen9pfsRing *rings;
> > } Xen9pfsDev;
> >
> > static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static void xen_9pfs_bh(void *opaque)
> > +{
> > +}
> > +
> > +static void xen_9pfs_evtchn_event(void *opaque)
> > +{
> > +}
> > +
> > static int xen_9pfs_free(struct XenDevice *xendev)
> > {
> > - return -1;
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> > +
>
> Coding style.
OK
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + if (xen_9pdev->rings[i].data != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].data,
> > + (1 << XEN_9PFS_RING_ORDER));
> > + }
> > + if (xen_9pdev->rings[i].intf != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].intf,
> > + 1);
> > + }
> > + if (xen_9pdev->rings[i].evtchndev > 0) {
> > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> > + NULL, NULL, NULL);
> > + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> > + }
> > + if (xen_9pdev->rings[i].bh != NULL) {
> > + qemu_bh_delete(xen_9pdev->rings[i].bh);
> > + }
> > + }
> > + g_free(xen_9pdev->rings);
> > + return 0;
> > }
> >
> > static int xen_9pfs_connect(struct XenDevice *xendev)
> > {
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
>
> Coding style.
OK
> > + V9fsState *s = &xen_9pdev->state;
> > + QemuOpts *fsdev;
> > + char *security_model, *path;
> > +
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> > + &xen_9pdev->num_rings) == -1 ||
> > + xen_9pdev->num_rings > MAX_RINGS) {
> > + return -1;
> > + }
> > +
> > + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + char str[16];
> > +
> > + xen_9pdev->rings[i].priv = xen_9pdev;
> > + xen_9pdev->rings[i].evtchn = -1;
> > + xen_9pdev->rings[i].local_port = -1;
> > +
> > + sprintf(str, "ring-ref%u", i);
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> > + &xen_9pdev->rings[i].ref) == -1) {
> > + goto out;
> > + }
> > + sprintf(str, "event-channel-%u", i);
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> > + &xen_9pdev->rings[i].evtchn) == -1) {
> > + goto out;
> > + }
> > +
> > + xen_9pdev->rings[i].intf = xengnttab_map_grant_ref(
> > + xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->xendev.dom,
> > + xen_9pdev->rings[i].ref,
> > + PROT_READ | PROT_WRITE);
> > + if (!xen_9pdev->rings[i].intf) {
> > + goto out;
> > + }
> > + xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
> > + xen_9pdev->xendev.gnttabdev,
> > + (1 << XEN_9PFS_RING_ORDER),
> > + xen_9pdev->xendev.dom,
> > + xen_9pdev->rings[i].intf->ref,
> > + PROT_READ | PROT_WRITE);
> > + if (!xen_9pdev->rings[i].data) {
> > + goto out;
> > + }
> > + xen_9pdev->rings[i].ring.in = xen_9pdev->rings[i].data;
> > + xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data + XEN_9PFS_RING_SIZE;
> > +
> > + xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]);
> > + xen_9pdev->rings[i].out_cons = 0;
> > + xen_9pdev->rings[i].out_size = 0;
> > + xen_9pdev->rings[i].inprogress = false;
> > +
> > +
> > + xen_9pdev->rings[i].evtchndev = xenevtchn_open(NULL, 0);
> > + if (xen_9pdev->rings[i].evtchndev == NULL) {
> > + goto out;
> > + }
> > + fcntl(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), F_SETFD, FD_CLOEXEC);
> > + xen_9pdev->rings[i].local_port = xenevtchn_bind_interdomain
> > + (xen_9pdev->rings[i].evtchndev, xendev->dom, xen_9pdev->rings[i].evtchn);
> > + if (xen_9pdev->rings[i].local_port == -1) {
> > + xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed port=%d\n",
> > + xen_9pdev->rings[i].evtchn);
> > + goto out;
> > + }
> > + xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
> > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> > + xen_9pfs_evtchn_event, NULL, &xen_9pdev->rings[i]);
> > + }
> > +
> > + security_model = xenstore_read_be_str(xendev, "security_model");
> > + path = xenstore_read_be_str(xendev, "path");
> > + s->fsconf.fsdev_id = g_malloc(strlen("xen9p") + 6);
> > + sprintf(s->fsconf.fsdev_id, "xen9p%d", xendev->dev);
>
> Please use g_strdup_printf().
I'll do
> > + s->fsconf.tag = xenstore_read_fe_str(xendev, "tag");
> > + v9fs_register_transport(s, &xen_9p_transport);
> > + fsdev = qemu_opts_create(qemu_find_opts("fsdev"),
> > + s->fsconf.tag,
> > + 1, NULL);
> > + qemu_opt_set(fsdev, "fsdriver", "local", NULL);
> > + qemu_opt_set(fsdev, "path", path, NULL);
> > + qemu_opt_set(fsdev, "security_model", security_model, NULL);
> > + qemu_opts_set_id(fsdev, s->fsconf.fsdev_id);
> > + qemu_fsdev_add(fsdev);
> > + v9fs_device_realize_common(s, NULL);
> > +
> > return 0;
> > +
> > +out:
> > + xen_9pfs_free(xendev);
> > + return -1;
> > }
> >
> > static void xen_9pfs_alloc(struct XenDevice *xendev)
> > {
> > + xenstore_write_be_str(xendev, "versions", VERSIONS);
> > + xenstore_write_be_int(xendev, "max-rings", MAX_RINGS);
> > + xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER);
> > }
> >
> > static void xen_9pfs_disconnect(struct XenDevice *xendev)
> > {
> > + /* Dynamic hotplug of PV filesystems at runtime is not supported. */
>
> Does this mean that this function is never called ? Or that it should
> report an error ? Or print one ?
This function is called, but only at shutdown.
> In any case, it looks weird that it doesn't free the fsdev_id that
> was allocated in xen_9pfs_connect().
I'll free it in xen_9pfs_free
> > }
> >
> > struct XenDevOps xen_9pfs_ops = {
>
>
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 5/9] xen/9pfs: connect to the frontend
@ 2017-03-15 21:30 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:30 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:56 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Write the limits of the backend to xenstore. Connect to the frontend.
> > Upon connection, allocate the rings according to the protocol
> > specification.
> >
> > Initialize a QEMUBH to schedule work upon receiving an event channel
> > notification from the frontend.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++-
> > 1 file changed, 158 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 35032d3..0e4a133 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -17,8 +17,35 @@
> > #include "qemu/config-file.h"
> > #include "fsdev/qemu-fsdev.h"
> >
> > +#define VERSIONS "1"
> > +#define MAX_RINGS 8
> > +#define MAX_RING_ORDER 8
> > +
> > +struct Xen9pfsRing {
> > + struct Xen9pfsDev *priv;
> > +
> > + int ref;
> > + xenevtchn_handle *evtchndev;
> > + int evtchn;
> > + int local_port;
> > + struct xen_9pfs_data_intf *intf;
> > + unsigned char *data;
> > + struct xen_9pfs_data ring;
> > +
> > + QEMUBH *bh;
> > +
> > + /* local copies, so that we can read/write PDU data directly from
> > + * the ring */
> > + RING_IDX out_cons, out_size, in_cons;
> > + bool inprogress;
> > +};
> > +
>
> QEMU Coding style requires a typedef.
OK
> FWIW, maybe you could also convert
> other structured types like XenDevice or XenDevOps.
I'll do in a separate series
> > typedef struct Xen9pfsDev {
> > struct XenDevice xendev; /* must be first */
> > + V9fsState state;
> > +
> > + int num_rings;
> > + struct Xen9pfsRing *rings;
> > } Xen9pfsDev;
> >
> > static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > @@ -67,22 +94,152 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static void xen_9pfs_bh(void *opaque)
> > +{
> > +}
> > +
> > +static void xen_9pfs_evtchn_event(void *opaque)
> > +{
> > +}
> > +
> > static int xen_9pfs_free(struct XenDevice *xendev)
> > {
> > - return -1;
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
> > +
>
> Coding style.
OK
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + if (xen_9pdev->rings[i].data != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].data,
> > + (1 << XEN_9PFS_RING_ORDER));
> > + }
> > + if (xen_9pdev->rings[i].intf != NULL) {
> > + xengnttab_unmap(xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->rings[i].intf,
> > + 1);
> > + }
> > + if (xen_9pdev->rings[i].evtchndev > 0) {
> > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> > + NULL, NULL, NULL);
> > + xenevtchn_unbind(xen_9pdev->rings[i].evtchndev, xen_9pdev->rings[i].local_port);
> > + }
> > + if (xen_9pdev->rings[i].bh != NULL) {
> > + qemu_bh_delete(xen_9pdev->rings[i].bh);
> > + }
> > + }
> > + g_free(xen_9pdev->rings);
> > + return 0;
> > }
> >
> > static int xen_9pfs_connect(struct XenDevice *xendev)
> > {
> > + int i;
> > + struct Xen9pfsDev *xen_9pdev = container_of(xendev, struct Xen9pfsDev, xendev);
>
> Coding style.
OK
> > + V9fsState *s = &xen_9pdev->state;
> > + QemuOpts *fsdev;
> > + char *security_model, *path;
> > +
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
> > + &xen_9pdev->num_rings) == -1 ||
> > + xen_9pdev->num_rings > MAX_RINGS) {
> > + return -1;
> > + }
> > +
> > + xen_9pdev->rings = g_malloc0(xen_9pdev->num_rings * sizeof(struct Xen9pfsRing));
> > + for (i = 0; i < xen_9pdev->num_rings; i++) {
> > + char str[16];
> > +
> > + xen_9pdev->rings[i].priv = xen_9pdev;
> > + xen_9pdev->rings[i].evtchn = -1;
> > + xen_9pdev->rings[i].local_port = -1;
> > +
> > + sprintf(str, "ring-ref%u", i);
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> > + &xen_9pdev->rings[i].ref) == -1) {
> > + goto out;
> > + }
> > + sprintf(str, "event-channel-%u", i);
> > + if (xenstore_read_fe_int(&xen_9pdev->xendev, str,
> > + &xen_9pdev->rings[i].evtchn) == -1) {
> > + goto out;
> > + }
> > +
> > + xen_9pdev->rings[i].intf = xengnttab_map_grant_ref(
> > + xen_9pdev->xendev.gnttabdev,
> > + xen_9pdev->xendev.dom,
> > + xen_9pdev->rings[i].ref,
> > + PROT_READ | PROT_WRITE);
> > + if (!xen_9pdev->rings[i].intf) {
> > + goto out;
> > + }
> > + xen_9pdev->rings[i].data = xengnttab_map_domain_grant_refs(
> > + xen_9pdev->xendev.gnttabdev,
> > + (1 << XEN_9PFS_RING_ORDER),
> > + xen_9pdev->xendev.dom,
> > + xen_9pdev->rings[i].intf->ref,
> > + PROT_READ | PROT_WRITE);
> > + if (!xen_9pdev->rings[i].data) {
> > + goto out;
> > + }
> > + xen_9pdev->rings[i].ring.in = xen_9pdev->rings[i].data;
> > + xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data + XEN_9PFS_RING_SIZE;
> > +
> > + xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]);
> > + xen_9pdev->rings[i].out_cons = 0;
> > + xen_9pdev->rings[i].out_size = 0;
> > + xen_9pdev->rings[i].inprogress = false;
> > +
> > +
> > + xen_9pdev->rings[i].evtchndev = xenevtchn_open(NULL, 0);
> > + if (xen_9pdev->rings[i].evtchndev == NULL) {
> > + goto out;
> > + }
> > + fcntl(xenevtchn_fd(xen_9pdev->rings[i].evtchndev), F_SETFD, FD_CLOEXEC);
> > + xen_9pdev->rings[i].local_port = xenevtchn_bind_interdomain
> > + (xen_9pdev->rings[i].evtchndev, xendev->dom, xen_9pdev->rings[i].evtchn);
> > + if (xen_9pdev->rings[i].local_port == -1) {
> > + xen_pv_printf(xendev, 0, "xenevtchn_bind_interdomain failed port=%d\n",
> > + xen_9pdev->rings[i].evtchn);
> > + goto out;
> > + }
> > + xen_pv_printf(xendev, 2, "bind evtchn port %d\n", xendev->local_port);
> > + qemu_set_fd_handler(xenevtchn_fd(xen_9pdev->rings[i].evtchndev),
> > + xen_9pfs_evtchn_event, NULL, &xen_9pdev->rings[i]);
> > + }
> > +
> > + security_model = xenstore_read_be_str(xendev, "security_model");
> > + path = xenstore_read_be_str(xendev, "path");
> > + s->fsconf.fsdev_id = g_malloc(strlen("xen9p") + 6);
> > + sprintf(s->fsconf.fsdev_id, "xen9p%d", xendev->dev);
>
> Please use g_strdup_printf().
I'll do
> > + s->fsconf.tag = xenstore_read_fe_str(xendev, "tag");
> > + v9fs_register_transport(s, &xen_9p_transport);
> > + fsdev = qemu_opts_create(qemu_find_opts("fsdev"),
> > + s->fsconf.tag,
> > + 1, NULL);
> > + qemu_opt_set(fsdev, "fsdriver", "local", NULL);
> > + qemu_opt_set(fsdev, "path", path, NULL);
> > + qemu_opt_set(fsdev, "security_model", security_model, NULL);
> > + qemu_opts_set_id(fsdev, s->fsconf.fsdev_id);
> > + qemu_fsdev_add(fsdev);
> > + v9fs_device_realize_common(s, NULL);
> > +
> > return 0;
> > +
> > +out:
> > + xen_9pfs_free(xendev);
> > + return -1;
> > }
> >
> > static void xen_9pfs_alloc(struct XenDevice *xendev)
> > {
> > + xenstore_write_be_str(xendev, "versions", VERSIONS);
> > + xenstore_write_be_int(xendev, "max-rings", MAX_RINGS);
> > + xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER);
> > }
> >
> > static void xen_9pfs_disconnect(struct XenDevice *xendev)
> > {
> > + /* Dynamic hotplug of PV filesystems at runtime is not supported. */
>
> Does this mean that this function is never called ? Or that it should
> report an error ? Or print one ?
This function is called, but only at shutdown.
> In any case, it looks weird that it doesn't free the fsdev_id that
> was allocated in xen_9pfs_connect().
I'll free it in xen_9pfs_free
> > }
> >
> > struct XenDevOps xen_9pfs_ops = {
>
>
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^ permalink raw reply [flat|nested] 72+ messages in thread
* [Qemu-devel] [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:55 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross, Aneesh Kumar K.V
Upon receiving an event channel notification from the frontend, schedule
the bottom half. From the bottom half, read one request from the ring,
create a pdu and call pdu_submit to handle it.
For now, only handle one request per ring at a time.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 47 insertions(+)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 0e4a133..741dd31 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
return 0;
}
+static int xen_9pfs_receive(struct Xen9pfsRing *ring)
+{
+ struct xen_9pfs_header h;
+ RING_IDX cons, prod, masked_prod, masked_cons;
+ V9fsPDU *pdu;
+
+ if (ring->inprogress) {
+ return 0;
+ }
+
+ cons = ring->intf->out_cons;
+ prod = ring->intf->out_prod;
+ xen_rmb();
+
+ if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
+ return 0;
+ }
+ ring->inprogress = true;
+
+ masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
+ masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
+
+ xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
+ XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
+
+ pdu = pdu_alloc(&ring->priv->state);
+ pdu->size = h.size;
+ pdu->id = h.id;
+ pdu->tag = h.tag;
+ ring->out_size = h.size;
+ ring->out_cons = cons + h.size;
+
+ qemu_co_queue_init(&pdu->complete);
+ pdu_submit(pdu);
+
+ return 0;
+}
+
static void xen_9pfs_bh(void *opaque)
{
+ struct Xen9pfsRing *ring = opaque;
+ xen_9pfs_receive(ring);
}
static void xen_9pfs_evtchn_event(void *opaque)
{
+ struct Xen9pfsRing *ring = opaque;
+ evtchn_port_t port;
+
+ port = xenevtchn_pending(ring->evtchndev);
+ xenevtchn_unmask(ring->evtchndev, port);
+
+ qemu_bh_schedule(ring->bh);
}
static int xen_9pfs_free(struct XenDevice *xendev)
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
Upon receiving an event channel notification from the frontend, schedule
the bottom half. From the bottom half, read one request from the ring,
create a pdu and call pdu_submit to handle it.
For now, only handle one request per ring at a time.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 47 insertions(+)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 0e4a133..741dd31 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
return 0;
}
+static int xen_9pfs_receive(struct Xen9pfsRing *ring)
+{
+ struct xen_9pfs_header h;
+ RING_IDX cons, prod, masked_prod, masked_cons;
+ V9fsPDU *pdu;
+
+ if (ring->inprogress) {
+ return 0;
+ }
+
+ cons = ring->intf->out_cons;
+ prod = ring->intf->out_prod;
+ xen_rmb();
+
+ if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
+ return 0;
+ }
+ ring->inprogress = true;
+
+ masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
+ masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
+
+ xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
+ XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
+
+ pdu = pdu_alloc(&ring->priv->state);
+ pdu->size = h.size;
+ pdu->id = h.id;
+ pdu->tag = h.tag;
+ ring->out_size = h.size;
+ ring->out_cons = cons + h.size;
+
+ qemu_co_queue_init(&pdu->complete);
+ pdu_submit(pdu);
+
+ return 0;
+}
+
static void xen_9pfs_bh(void *opaque)
{
+ struct Xen9pfsRing *ring = opaque;
+ xen_9pfs_receive(ring);
}
static void xen_9pfs_evtchn_event(void *opaque)
{
+ struct Xen9pfsRing *ring = opaque;
+ evtchn_port_t port;
+
+ port = xenevtchn_pending(ring->evtchndev);
+ xenevtchn_unmask(ring->evtchndev, port);
+
+ qemu_bh_schedule(ring->bh);
}
static int xen_9pfs_free(struct XenDevice *xendev)
--
1.9.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-15 10:51 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 10:51 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini,
jgross, Aneesh Kumar K.V
[-- Attachment #1: Type: text/plain, Size: 2807 bytes --]
On Mon, 13 Mar 2017 16:55:57 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Upon receiving an event channel notification from the frontend, schedule
> the bottom half. From the bottom half, read one request from the ring,
> create a pdu and call pdu_submit to handle it.
>
> For now, only handle one request per ring at a time.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 47 insertions(+)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 0e4a133..741dd31 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
Coding style for structured types.
> +{
> + struct xen_9pfs_header h;
> + RING_IDX cons, prod, masked_prod, masked_cons;
> + V9fsPDU *pdu;
> +
> + if (ring->inprogress) {
> + return 0;
> + }
> +
> + cons = ring->intf->out_cons;
> + prod = ring->intf->out_prod;
> + xen_rmb();
> +
> + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> + return 0;
> + }
> + ring->inprogress = true;
> +
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> +
> + pdu = pdu_alloc(&ring->priv->state);
pdu_alloc() can theoretically return NULL. Maybe add a comment to
indicate this won't happen because "for now [we] only handle one
request per ring at a time".
> + pdu->size = h.size;
> + pdu->id = h.id;
> + pdu->tag = h.tag;
> + ring->out_size = h.size;
> + ring->out_cons = cons + h.size;
> +
> + qemu_co_queue_init(&pdu->complete);
> + pdu_submit(pdu);
> +
> + return 0;
> +}
> +
> static void xen_9pfs_bh(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
Coding style for structured types.
> + xen_9pfs_receive(ring);
> }
>
> static void xen_9pfs_evtchn_event(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
Coding style for structured types.
> + evtchn_port_t port;
> +
> + port = xenevtchn_pending(ring->evtchndev);
> + xenevtchn_unmask(ring->evtchndev, port);
> +
> + qemu_bh_schedule(ring->bh);
> }
>
> static int xen_9pfs_free(struct XenDevice *xendev)
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
@ 2017-03-15 10:51 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 10:51 UTC (permalink / raw)
To: Stefano Stabellini
Cc: jgross, qemu-devel, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
[-- Attachment #1.1: Type: text/plain, Size: 2807 bytes --]
On Mon, 13 Mar 2017 16:55:57 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Upon receiving an event channel notification from the frontend, schedule
> the bottom half. From the bottom half, read one request from the ring,
> create a pdu and call pdu_submit to handle it.
>
> For now, only handle one request per ring at a time.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 47 insertions(+)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 0e4a133..741dd31 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
Coding style for structured types.
> +{
> + struct xen_9pfs_header h;
> + RING_IDX cons, prod, masked_prod, masked_cons;
> + V9fsPDU *pdu;
> +
> + if (ring->inprogress) {
> + return 0;
> + }
> +
> + cons = ring->intf->out_cons;
> + prod = ring->intf->out_prod;
> + xen_rmb();
> +
> + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> + return 0;
> + }
> + ring->inprogress = true;
> +
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> +
> + pdu = pdu_alloc(&ring->priv->state);
pdu_alloc() can theoretically return NULL. Maybe add a comment to
indicate this won't happen because "for now [we] only handle one
request per ring at a time".
> + pdu->size = h.size;
> + pdu->id = h.id;
> + pdu->tag = h.tag;
> + ring->out_size = h.size;
> + ring->out_cons = cons + h.size;
> +
> + qemu_co_queue_init(&pdu->complete);
> + pdu_submit(pdu);
> +
> + return 0;
> +}
> +
> static void xen_9pfs_bh(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
Coding style for structured types.
> + xen_9pfs_receive(ring);
> }
>
> static void xen_9pfs_evtchn_event(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
Coding style for structured types.
> + evtchn_port_t port;
> +
> + port = xenevtchn_pending(ring->evtchndev);
> + xenevtchn_unmask(ring->evtchndev, port);
> +
> + qemu_bh_schedule(ring->bh);
> }
>
> static int xen_9pfs_free(struct XenDevice *xendev)
[-- Attachment #1.2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
[-- Attachment #2: Type: text/plain, Size: 127 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
2017-03-15 10:51 ` Greg Kurz
@ 2017-03-15 21:56 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:56 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, jgross, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:57 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Upon receiving an event channel notification from the frontend, schedule
> > the bottom half. From the bottom half, read one request from the ring,
> > create a pdu and call pdu_submit to handle it.
> >
> > For now, only handle one request per ring at a time.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 47 insertions(+)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 0e4a133..741dd31 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
>
> Coding style for structured types.
I'll fix
> > +{
> > + struct xen_9pfs_header h;
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > + V9fsPDU *pdu;
> > +
> > + if (ring->inprogress) {
> > + return 0;
> > + }
> > +
> > + cons = ring->intf->out_cons;
> > + prod = ring->intf->out_prod;
> > + xen_rmb();
> > +
> > + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> > + return 0;
> > + }
> > + ring->inprogress = true;
> > +
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> > + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> > +
> > + pdu = pdu_alloc(&ring->priv->state);
>
> pdu_alloc() can theoretically return NULL. Maybe add a comment to
> indicate this won't happen because "for now [we] only handle one
> request per ring at a time".
OK
> > + pdu->size = h.size;
> > + pdu->id = h.id;
> > + pdu->tag = h.tag;
> > + ring->out_size = h.size;
> > + ring->out_cons = cons + h.size;
> > +
> > + qemu_co_queue_init(&pdu->complete);
> > + pdu_submit(pdu);
> > +
> > + return 0;
> > +}
> > +
> > static void xen_9pfs_bh(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
>
> Coding style for structured types.
OK
> > + xen_9pfs_receive(ring);
> > }
> >
> > static void xen_9pfs_evtchn_event(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
>
> Coding style for structured types.
OK
> > + evtchn_port_t port;
> > +
> > + port = xenevtchn_pending(ring->evtchndev);
> > + xenevtchn_unmask(ring->evtchndev, port);
> > +
> > + qemu_bh_schedule(ring->bh);
> > }
> >
> > static int xen_9pfs_free(struct XenDevice *xendev)
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
@ 2017-03-15 21:56 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:56 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:57 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Upon receiving an event channel notification from the frontend, schedule
> > the bottom half. From the bottom half, read one request from the ring,
> > create a pdu and call pdu_submit to handle it.
> >
> > For now, only handle one request per ring at a time.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 47 insertions(+)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 0e4a133..741dd31 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
>
> Coding style for structured types.
I'll fix
> > +{
> > + struct xen_9pfs_header h;
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > + V9fsPDU *pdu;
> > +
> > + if (ring->inprogress) {
> > + return 0;
> > + }
> > +
> > + cons = ring->intf->out_cons;
> > + prod = ring->intf->out_prod;
> > + xen_rmb();
> > +
> > + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> > + return 0;
> > + }
> > + ring->inprogress = true;
> > +
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> > + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> > +
> > + pdu = pdu_alloc(&ring->priv->state);
>
> pdu_alloc() can theoretically return NULL. Maybe add a comment to
> indicate this won't happen because "for now [we] only handle one
> request per ring at a time".
OK
> > + pdu->size = h.size;
> > + pdu->id = h.id;
> > + pdu->tag = h.tag;
> > + ring->out_size = h.size;
> > + ring->out_cons = cons + h.size;
> > +
> > + qemu_co_queue_init(&pdu->complete);
> > + pdu_submit(pdu);
> > +
> > + return 0;
> > +}
> > +
> > static void xen_9pfs_bh(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
>
> Coding style for structured types.
OK
> > + xen_9pfs_receive(ring);
> > }
> >
> > static void xen_9pfs_evtchn_event(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
>
> Coding style for structured types.
OK
> > + evtchn_port_t port;
> > +
> > + port = xenevtchn_pending(ring->evtchndev);
> > + xenevtchn_unmask(ring->evtchndev, port);
> > +
> > + qemu_bh_schedule(ring->bh);
> > }
> >
> > static int xen_9pfs_free(struct XenDevice *xendev)
_______________________________________________
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Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-15 11:53 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 11:53 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini,
jgross, Aneesh Kumar K.V
[-- Attachment #1: Type: text/plain, Size: 2743 bytes --]
On Mon, 13 Mar 2017 16:55:57 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Upon receiving an event channel notification from the frontend, schedule
> the bottom half. From the bottom half, read one request from the ring,
> create a pdu and call pdu_submit to handle it.
>
> For now, only handle one request per ring at a time.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
Oops, one more remark I forgot in my the previous mail. See below.
> hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 47 insertions(+)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 0e4a133..741dd31 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
> +{
> + struct xen_9pfs_header h;
> + RING_IDX cons, prod, masked_prod, masked_cons;
> + V9fsPDU *pdu;
> +
> + if (ring->inprogress) {
> + return 0;
> + }
> +
> + cons = ring->intf->out_cons;
> + prod = ring->intf->out_prod;
> + xen_rmb();
> +
> + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> + return 0;
> + }
> + ring->inprogress = true;
> +
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> +
> + pdu = pdu_alloc(&ring->priv->state);
> + pdu->size = h.size;
9P uses little-endian, so this should be:
pdu->size = le32_to_cpu(h.size);
> + pdu->id = h.id;
> + pdu->tag = h.tag;
and:
pdu->tag = le16_to_cpu(h.tag);
> + ring->out_size = h.size;
> + ring->out_cons = cons + h.size;
Same here.
> +
> + qemu_co_queue_init(&pdu->complete);
> + pdu_submit(pdu);
> +
> + return 0;
> +}
> +
> static void xen_9pfs_bh(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
> + xen_9pfs_receive(ring);
> }
>
> static void xen_9pfs_evtchn_event(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
> + evtchn_port_t port;
> +
> + port = xenevtchn_pending(ring->evtchndev);
> + xenevtchn_unmask(ring->evtchndev, port);
> +
> + qemu_bh_schedule(ring->bh);
> }
>
> static int xen_9pfs_free(struct XenDevice *xendev)
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
@ 2017-03-15 11:53 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 11:53 UTC (permalink / raw)
To: Stefano Stabellini
Cc: jgross, qemu-devel, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
[-- Attachment #1.1: Type: text/plain, Size: 2743 bytes --]
On Mon, 13 Mar 2017 16:55:57 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Upon receiving an event channel notification from the frontend, schedule
> the bottom half. From the bottom half, read one request from the ring,
> create a pdu and call pdu_submit to handle it.
>
> For now, only handle one request per ring at a time.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
Oops, one more remark I forgot in my the previous mail. See below.
> hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 47 insertions(+)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 0e4a133..741dd31 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> return 0;
> }
>
> +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
> +{
> + struct xen_9pfs_header h;
> + RING_IDX cons, prod, masked_prod, masked_cons;
> + V9fsPDU *pdu;
> +
> + if (ring->inprogress) {
> + return 0;
> + }
> +
> + cons = ring->intf->out_cons;
> + prod = ring->intf->out_prod;
> + xen_rmb();
> +
> + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> + return 0;
> + }
> + ring->inprogress = true;
> +
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> +
> + pdu = pdu_alloc(&ring->priv->state);
> + pdu->size = h.size;
9P uses little-endian, so this should be:
pdu->size = le32_to_cpu(h.size);
> + pdu->id = h.id;
> + pdu->tag = h.tag;
and:
pdu->tag = le16_to_cpu(h.tag);
> + ring->out_size = h.size;
> + ring->out_cons = cons + h.size;
Same here.
> +
> + qemu_co_queue_init(&pdu->complete);
> + pdu_submit(pdu);
> +
> + return 0;
> +}
> +
> static void xen_9pfs_bh(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
> + xen_9pfs_receive(ring);
> }
>
> static void xen_9pfs_evtchn_event(void *opaque)
> {
> + struct Xen9pfsRing *ring = opaque;
> + evtchn_port_t port;
> +
> + port = xenevtchn_pending(ring->evtchndev);
> + xenevtchn_unmask(ring->evtchndev, port);
> +
> + qemu_bh_schedule(ring->bh);
> }
>
> static int xen_9pfs_free(struct XenDevice *xendev)
[-- Attachment #1.2: OpenPGP digital signature --]
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[-- Attachment #2: Type: text/plain, Size: 127 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
2017-03-15 11:53 ` Greg Kurz
@ 2017-03-15 22:03 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 22:03 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, jgross, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:57 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Upon receiving an event channel notification from the frontend, schedule
> > the bottom half. From the bottom half, read one request from the ring,
> > create a pdu and call pdu_submit to handle it.
> >
> > For now, only handle one request per ring at a time.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
>
> Oops, one more remark I forgot in my the previous mail. See below.
>
> > hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 47 insertions(+)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 0e4a133..741dd31 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
> > +{
> > + struct xen_9pfs_header h;
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > + V9fsPDU *pdu;
> > +
> > + if (ring->inprogress) {
> > + return 0;
> > + }
> > +
> > + cons = ring->intf->out_cons;
> > + prod = ring->intf->out_prod;
> > + xen_rmb();
> > +
> > + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> > + return 0;
> > + }
> > + ring->inprogress = true;
> > +
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> > + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> > +
> > + pdu = pdu_alloc(&ring->priv->state);
> > + pdu->size = h.size;
>
> 9P uses little-endian, so this should be:
>
> pdu->size = le32_to_cpu(h.size);
>
> > + pdu->id = h.id;
> > + pdu->tag = h.tag;
>
> and:
>
> pdu->tag = le16_to_cpu(h.tag);
>
> > + ring->out_size = h.size;
> > + ring->out_cons = cons + h.size;
>
> Same here.
OK, thanks. Xen doesn't support big endian today, but they don't hurt.
> > +
> > + qemu_co_queue_init(&pdu->complete);
> > + pdu_submit(pdu);
> > +
> > + return 0;
> > +}
> > +
> > static void xen_9pfs_bh(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
> > + xen_9pfs_receive(ring);
> > }
> >
> > static void xen_9pfs_evtchn_event(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
> > + evtchn_port_t port;
> > +
> > + port = xenevtchn_pending(ring->evtchndev);
> > + xenevtchn_unmask(ring->evtchndev, port);
> > +
> > + qemu_bh_schedule(ring->bh);
> > }
> >
> > static int xen_9pfs_free(struct XenDevice *xendev)
>
>
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 6/9] xen/9pfs: receive requests from the frontend
@ 2017-03-15 22:03 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 22:03 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:57 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Upon receiving an event channel notification from the frontend, schedule
> > the bottom half. From the bottom half, read one request from the ring,
> > create a pdu and call pdu_submit to handle it.
> >
> > For now, only handle one request per ring at a time.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
>
> Oops, one more remark I forgot in my the previous mail. See below.
>
> > hw/9pfs/xen-9p-backend.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
> > 1 file changed, 47 insertions(+)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 0e4a133..741dd31 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -94,12 +94,59 @@ static int xen_9pfs_init(struct XenDevice *xendev)
> > return 0;
> > }
> >
> > +static int xen_9pfs_receive(struct Xen9pfsRing *ring)
> > +{
> > + struct xen_9pfs_header h;
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > + V9fsPDU *pdu;
> > +
> > + if (ring->inprogress) {
> > + return 0;
> > + }
> > +
> > + cons = ring->intf->out_cons;
> > + prod = ring->intf->out_prod;
> > + xen_rmb();
> > +
> > + if (xen_9pfs_queued(prod, cons, XEN_9PFS_RING_SIZE) < sizeof(h)) {
> > + return 0;
> > + }
> > + ring->inprogress = true;
> > +
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + xen_9pfs_read_packet(ring->ring.out, masked_prod, &masked_cons,
> > + XEN_9PFS_RING_SIZE, (uint8_t*) &h, sizeof(h));
> > +
> > + pdu = pdu_alloc(&ring->priv->state);
> > + pdu->size = h.size;
>
> 9P uses little-endian, so this should be:
>
> pdu->size = le32_to_cpu(h.size);
>
> > + pdu->id = h.id;
> > + pdu->tag = h.tag;
>
> and:
>
> pdu->tag = le16_to_cpu(h.tag);
>
> > + ring->out_size = h.size;
> > + ring->out_cons = cons + h.size;
>
> Same here.
OK, thanks. Xen doesn't support big endian today, but they don't hurt.
> > +
> > + qemu_co_queue_init(&pdu->complete);
> > + pdu_submit(pdu);
> > +
> > + return 0;
> > +}
> > +
> > static void xen_9pfs_bh(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
> > + xen_9pfs_receive(ring);
> > }
> >
> > static void xen_9pfs_evtchn_event(void *opaque)
> > {
> > + struct Xen9pfsRing *ring = opaque;
> > + evtchn_port_t port;
> > +
> > + port = xenevtchn_pending(ring->evtchndev);
> > + xenevtchn_unmask(ring->evtchndev, port);
> > +
> > + qemu_bh_schedule(ring->bh);
> > }
> >
> > static int xen_9pfs_free(struct XenDevice *xendev)
>
>
_______________________________________________
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Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* [Qemu-devel] [PATCH v2 7/9] xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:55 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross, Aneesh Kumar K.V
Implement xen_9pfs_init_in/out_iov_from_pdu and
xen_9pfs_pdu_vmarshal/vunmarshall by creating new sg pointing to the
data on the ring.
This is safe as we only handle one request per ring at any given time.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 89 insertions(+), 2 deletions(-)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 741dd31..d72a749 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -48,12 +48,77 @@ typedef struct Xen9pfsDev {
struct Xen9pfsRing *rings;
} Xen9pfsDev;
+static void xen_9pfs_in_sg(struct Xen9pfsRing *ring,
+ struct iovec *in_sg,
+ int *num,
+ uint32_t idx,
+ uint32_t size)
+{
+ RING_IDX cons, prod, masked_prod, masked_cons;
+
+ cons = ring->intf->in_cons;
+ prod = ring->intf->in_prod;
+ xen_rmb();
+ masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
+ masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
+
+ if (masked_prod < masked_cons) {
+ in_sg[0].iov_base = ring->ring.in + masked_prod;
+ in_sg[0].iov_len = masked_cons - masked_prod;
+ *num = 1;
+ } else {
+ in_sg[0].iov_base = ring->ring.in + masked_prod;
+ in_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_prod;
+ in_sg[1].iov_base = ring->ring.in;
+ in_sg[1].iov_len = masked_cons;
+ *num = 2;
+ }
+}
+
+static void xen_9pfs_out_sg(struct Xen9pfsRing *ring,
+ struct iovec *out_sg,
+ int *num,
+ uint32_t idx)
+{
+ RING_IDX cons, prod, masked_prod, masked_cons;
+
+ cons = ring->intf->out_cons;
+ prod = ring->intf->out_prod;
+ xen_rmb();
+ masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
+ masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
+
+ if (masked_cons < masked_prod) {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = ring->out_size;
+ *num = 1;
+ } else {
+ if (ring->out_size > (XEN_9PFS_RING_SIZE - masked_cons)) {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_cons;
+ out_sg[1].iov_base = ring->ring.out;
+ out_sg[1].iov_len = ring->out_size - (XEN_9PFS_RING_SIZE - masked_cons);
+ *num = 2;
+ } else {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = ring->out_size;
+ *num = 1;
+ }
+ }
+}
+
static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
size_t offset,
const char *fmt,
va_list ap)
{
- return 0;
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct iovec in_sg[2];
+ int num;
+
+ xen_9pfs_in_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
+ in_sg, &num, pdu->idx, ROUND_UP(offset + 128, 512));
+ return v9fs_iov_vmarshal(in_sg, num, offset, 0, fmt, ap);
}
static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
@@ -61,13 +126,27 @@ static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
const char *fmt,
va_list ap)
{
- return 0;
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct iovec out_sg[2];
+ int num;
+
+ xen_9pfs_out_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
+ out_sg, &num, pdu->idx);
+ return v9fs_iov_vunmarshal(out_sg, num, offset, 0, fmt, ap);
}
static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
struct iovec **piov,
unsigned int *pniov)
{
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
+ struct iovec *sg = g_malloc0(sizeof(*sg)*2);
+ int num;
+
+ xen_9pfs_out_sg(ring, sg, &num, pdu->idx);
+ *piov = sg;
+ *pniov = num;
}
static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
@@ -75,6 +154,14 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
unsigned int *pniov,
size_t size)
{
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
+ struct iovec *sg = g_malloc0(sizeof(*sg)*2);
+ int num;
+
+ xen_9pfs_in_sg(ring, sg, &num, pdu->idx, size);
+ *piov = sg;
+ *pniov = num;
}
static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 7/9] xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
Implement xen_9pfs_init_in/out_iov_from_pdu and
xen_9pfs_pdu_vmarshal/vunmarshall by creating new sg pointing to the
data on the ring.
This is safe as we only handle one request per ring at any given time.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++--
1 file changed, 89 insertions(+), 2 deletions(-)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 741dd31..d72a749 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -48,12 +48,77 @@ typedef struct Xen9pfsDev {
struct Xen9pfsRing *rings;
} Xen9pfsDev;
+static void xen_9pfs_in_sg(struct Xen9pfsRing *ring,
+ struct iovec *in_sg,
+ int *num,
+ uint32_t idx,
+ uint32_t size)
+{
+ RING_IDX cons, prod, masked_prod, masked_cons;
+
+ cons = ring->intf->in_cons;
+ prod = ring->intf->in_prod;
+ xen_rmb();
+ masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
+ masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
+
+ if (masked_prod < masked_cons) {
+ in_sg[0].iov_base = ring->ring.in + masked_prod;
+ in_sg[0].iov_len = masked_cons - masked_prod;
+ *num = 1;
+ } else {
+ in_sg[0].iov_base = ring->ring.in + masked_prod;
+ in_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_prod;
+ in_sg[1].iov_base = ring->ring.in;
+ in_sg[1].iov_len = masked_cons;
+ *num = 2;
+ }
+}
+
+static void xen_9pfs_out_sg(struct Xen9pfsRing *ring,
+ struct iovec *out_sg,
+ int *num,
+ uint32_t idx)
+{
+ RING_IDX cons, prod, masked_prod, masked_cons;
+
+ cons = ring->intf->out_cons;
+ prod = ring->intf->out_prod;
+ xen_rmb();
+ masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
+ masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
+
+ if (masked_cons < masked_prod) {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = ring->out_size;
+ *num = 1;
+ } else {
+ if (ring->out_size > (XEN_9PFS_RING_SIZE - masked_cons)) {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_cons;
+ out_sg[1].iov_base = ring->ring.out;
+ out_sg[1].iov_len = ring->out_size - (XEN_9PFS_RING_SIZE - masked_cons);
+ *num = 2;
+ } else {
+ out_sg[0].iov_base = ring->ring.out + masked_cons;
+ out_sg[0].iov_len = ring->out_size;
+ *num = 1;
+ }
+ }
+}
+
static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
size_t offset,
const char *fmt,
va_list ap)
{
- return 0;
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct iovec in_sg[2];
+ int num;
+
+ xen_9pfs_in_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
+ in_sg, &num, pdu->idx, ROUND_UP(offset + 128, 512));
+ return v9fs_iov_vmarshal(in_sg, num, offset, 0, fmt, ap);
}
static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
@@ -61,13 +126,27 @@ static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
const char *fmt,
va_list ap)
{
- return 0;
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct iovec out_sg[2];
+ int num;
+
+ xen_9pfs_out_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
+ out_sg, &num, pdu->idx);
+ return v9fs_iov_vunmarshal(out_sg, num, offset, 0, fmt, ap);
}
static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
struct iovec **piov,
unsigned int *pniov)
{
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
+ struct iovec *sg = g_malloc0(sizeof(*sg)*2);
+ int num;
+
+ xen_9pfs_out_sg(ring, sg, &num, pdu->idx);
+ *piov = sg;
+ *pniov = num;
}
static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
@@ -75,6 +154,14 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
unsigned int *pniov,
size_t size)
{
+ struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
+ struct iovec *sg = g_malloc0(sizeof(*sg)*2);
+ int num;
+
+ xen_9pfs_in_sg(ring, sg, &num, pdu->idx, size);
+ *piov = sg;
+ *pniov = num;
}
static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
--
1.9.1
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^ permalink raw reply related [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 7/9] xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-15 10:58 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 10:58 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini,
jgross, Aneesh Kumar K.V
[-- Attachment #1: Type: text/plain, Size: 5897 bytes --]
On Mon, 13 Mar 2017 16:55:58 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Implement xen_9pfs_init_in/out_iov_from_pdu and
> xen_9pfs_pdu_vmarshal/vunmarshall by creating new sg pointing to the
> data on the ring.
>
> This is safe as we only handle one request per ring at any given time.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 89 insertions(+), 2 deletions(-)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 741dd31..d72a749 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -48,12 +48,77 @@ typedef struct Xen9pfsDev {
> struct Xen9pfsRing *rings;
> } Xen9pfsDev;
>
> +static void xen_9pfs_in_sg(struct Xen9pfsRing *ring,
Coding style for structured types.
> + struct iovec *in_sg,
> + int *num,
> + uint32_t idx,
> + uint32_t size)
> +{
> + RING_IDX cons, prod, masked_prod, masked_cons;
> +
> + cons = ring->intf->in_cons;
> + prod = ring->intf->in_prod;
> + xen_rmb();
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + if (masked_prod < masked_cons) {
> + in_sg[0].iov_base = ring->ring.in + masked_prod;
> + in_sg[0].iov_len = masked_cons - masked_prod;
> + *num = 1;
> + } else {
> + in_sg[0].iov_base = ring->ring.in + masked_prod;
> + in_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_prod;
> + in_sg[1].iov_base = ring->ring.in;
> + in_sg[1].iov_len = masked_cons;
> + *num = 2;
> + }
> +}
> +
> +static void xen_9pfs_out_sg(struct Xen9pfsRing *ring,
Coding style for structured types.
> + struct iovec *out_sg,
> + int *num,
> + uint32_t idx)
> +{
> + RING_IDX cons, prod, masked_prod, masked_cons;
> +
> + cons = ring->intf->out_cons;
> + prod = ring->intf->out_prod;
> + xen_rmb();
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + if (masked_cons < masked_prod) {
> + out_sg[0].iov_base = ring->ring.out + masked_cons;
> + out_sg[0].iov_len = ring->out_size;
> + *num = 1;
> + } else {
> + if (ring->out_size > (XEN_9PFS_RING_SIZE - masked_cons)) {
> + out_sg[0].iov_base = ring->ring.out + masked_cons;
> + out_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_cons;
> + out_sg[1].iov_base = ring->ring.out;
> + out_sg[1].iov_len = ring->out_size - (XEN_9PFS_RING_SIZE - masked_cons);
> + *num = 2;
> + } else {
> + out_sg[0].iov_base = ring->ring.out + masked_cons;
> + out_sg[0].iov_len = ring->out_size;
> + *num = 1;
> + }
> + }
> +}
> +
> static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> size_t offset,
> const char *fmt,
> va_list ap)
> {
> - return 0;
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
Coding style for structured types.
> + struct iovec in_sg[2];
> + int num;
> +
> + xen_9pfs_in_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> + in_sg, &num, pdu->idx, ROUND_UP(offset + 128, 512));
> + return v9fs_iov_vmarshal(in_sg, num, offset, 0, fmt, ap);
> }
>
> static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> @@ -61,13 +126,27 @@ static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> const char *fmt,
> va_list ap)
> {
> - return 0;
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
Coding style for structured types.
> + struct iovec out_sg[2];
> + int num;
> +
> + xen_9pfs_out_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> + out_sg, &num, pdu->idx);
> + return v9fs_iov_vunmarshal(out_sg, num, offset, 0, fmt, ap);
> }
>
> static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> struct iovec **piov,
> unsigned int *pniov)
> {
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
Coding style for structured types.
> + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> + int num;
> +
> + xen_9pfs_out_sg(ring, sg, &num, pdu->idx);
> + *piov = sg;
> + *pniov = num;
> }
>
> static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> @@ -75,6 +154,14 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> unsigned int *pniov,
> size_t size)
> {
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
Coding style for structured types.
> + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> + int num;
> +
> + xen_9pfs_in_sg(ring, sg, &num, pdu->idx, size);
> + *piov = sg;
> + *pniov = num;
> }
>
> static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 7/9] xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
@ 2017-03-15 10:58 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 10:58 UTC (permalink / raw)
To: Stefano Stabellini
Cc: jgross, qemu-devel, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
[-- Attachment #1.1: Type: text/plain, Size: 5897 bytes --]
On Mon, 13 Mar 2017 16:55:58 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Implement xen_9pfs_init_in/out_iov_from_pdu and
> xen_9pfs_pdu_vmarshal/vunmarshall by creating new sg pointing to the
> data on the ring.
>
> This is safe as we only handle one request per ring at any given time.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 89 insertions(+), 2 deletions(-)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index 741dd31..d72a749 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -48,12 +48,77 @@ typedef struct Xen9pfsDev {
> struct Xen9pfsRing *rings;
> } Xen9pfsDev;
>
> +static void xen_9pfs_in_sg(struct Xen9pfsRing *ring,
Coding style for structured types.
> + struct iovec *in_sg,
> + int *num,
> + uint32_t idx,
> + uint32_t size)
> +{
> + RING_IDX cons, prod, masked_prod, masked_cons;
> +
> + cons = ring->intf->in_cons;
> + prod = ring->intf->in_prod;
> + xen_rmb();
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + if (masked_prod < masked_cons) {
> + in_sg[0].iov_base = ring->ring.in + masked_prod;
> + in_sg[0].iov_len = masked_cons - masked_prod;
> + *num = 1;
> + } else {
> + in_sg[0].iov_base = ring->ring.in + masked_prod;
> + in_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_prod;
> + in_sg[1].iov_base = ring->ring.in;
> + in_sg[1].iov_len = masked_cons;
> + *num = 2;
> + }
> +}
> +
> +static void xen_9pfs_out_sg(struct Xen9pfsRing *ring,
Coding style for structured types.
> + struct iovec *out_sg,
> + int *num,
> + uint32_t idx)
> +{
> + RING_IDX cons, prod, masked_prod, masked_cons;
> +
> + cons = ring->intf->out_cons;
> + prod = ring->intf->out_prod;
> + xen_rmb();
> + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> +
> + if (masked_cons < masked_prod) {
> + out_sg[0].iov_base = ring->ring.out + masked_cons;
> + out_sg[0].iov_len = ring->out_size;
> + *num = 1;
> + } else {
> + if (ring->out_size > (XEN_9PFS_RING_SIZE - masked_cons)) {
> + out_sg[0].iov_base = ring->ring.out + masked_cons;
> + out_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_cons;
> + out_sg[1].iov_base = ring->ring.out;
> + out_sg[1].iov_len = ring->out_size - (XEN_9PFS_RING_SIZE - masked_cons);
> + *num = 2;
> + } else {
> + out_sg[0].iov_base = ring->ring.out + masked_cons;
> + out_sg[0].iov_len = ring->out_size;
> + *num = 1;
> + }
> + }
> +}
> +
> static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> size_t offset,
> const char *fmt,
> va_list ap)
> {
> - return 0;
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
Coding style for structured types.
> + struct iovec in_sg[2];
> + int num;
> +
> + xen_9pfs_in_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> + in_sg, &num, pdu->idx, ROUND_UP(offset + 128, 512));
> + return v9fs_iov_vmarshal(in_sg, num, offset, 0, fmt, ap);
> }
>
> static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> @@ -61,13 +126,27 @@ static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> const char *fmt,
> va_list ap)
> {
> - return 0;
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
Coding style for structured types.
> + struct iovec out_sg[2];
> + int num;
> +
> + xen_9pfs_out_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> + out_sg, &num, pdu->idx);
> + return v9fs_iov_vunmarshal(out_sg, num, offset, 0, fmt, ap);
> }
>
> static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> struct iovec **piov,
> unsigned int *pniov)
> {
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
Coding style for structured types.
> + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> + int num;
> +
> + xen_9pfs_out_sg(ring, sg, &num, pdu->idx);
> + *piov = sg;
> + *pniov = num;
> }
>
> static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> @@ -75,6 +154,14 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> unsigned int *pniov,
> size_t size)
> {
> + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
Coding style for structured types.
> + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> + int num;
> +
> + xen_9pfs_in_sg(ring, sg, &num, pdu->idx, size);
> + *piov = sg;
> + *pniov = num;
> }
>
> static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
[-- Attachment #1.2: OpenPGP digital signature --]
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[-- Attachment #2: Type: text/plain, Size: 127 bytes --]
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 7/9] xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
2017-03-15 10:58 ` Greg Kurz
@ 2017-03-15 21:58 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:58 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, jgross, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:58 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Implement xen_9pfs_init_in/out_iov_from_pdu and
> > xen_9pfs_pdu_vmarshal/vunmarshall by creating new sg pointing to the
> > data on the ring.
> >
> > This is safe as we only handle one request per ring at any given time.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++--
> > 1 file changed, 89 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 741dd31..d72a749 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -48,12 +48,77 @@ typedef struct Xen9pfsDev {
> > struct Xen9pfsRing *rings;
> > } Xen9pfsDev;
> >
> > +static void xen_9pfs_in_sg(struct Xen9pfsRing *ring,
>
> Coding style for structured types.
OK
> > + struct iovec *in_sg,
> > + int *num,
> > + uint32_t idx,
> > + uint32_t size)
> > +{
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > +
> > + cons = ring->intf->in_cons;
> > + prod = ring->intf->in_prod;
> > + xen_rmb();
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + if (masked_prod < masked_cons) {
> > + in_sg[0].iov_base = ring->ring.in + masked_prod;
> > + in_sg[0].iov_len = masked_cons - masked_prod;
> > + *num = 1;
> > + } else {
> > + in_sg[0].iov_base = ring->ring.in + masked_prod;
> > + in_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_prod;
> > + in_sg[1].iov_base = ring->ring.in;
> > + in_sg[1].iov_len = masked_cons;
> > + *num = 2;
> > + }
> > +}
> > +
> > +static void xen_9pfs_out_sg(struct Xen9pfsRing *ring,
>
> Coding style for structured types.
OK
> > + struct iovec *out_sg,
> > + int *num,
> > + uint32_t idx)
> > +{
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > +
> > + cons = ring->intf->out_cons;
> > + prod = ring->intf->out_prod;
> > + xen_rmb();
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + if (masked_cons < masked_prod) {
> > + out_sg[0].iov_base = ring->ring.out + masked_cons;
> > + out_sg[0].iov_len = ring->out_size;
> > + *num = 1;
> > + } else {
> > + if (ring->out_size > (XEN_9PFS_RING_SIZE - masked_cons)) {
> > + out_sg[0].iov_base = ring->ring.out + masked_cons;
> > + out_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_cons;
> > + out_sg[1].iov_base = ring->ring.out;
> > + out_sg[1].iov_len = ring->out_size - (XEN_9PFS_RING_SIZE - masked_cons);
> > + *num = 2;
> > + } else {
> > + out_sg[0].iov_base = ring->ring.out + masked_cons;
> > + out_sg[0].iov_len = ring->out_size;
> > + *num = 1;
> > + }
> > + }
> > +}
> > +
> > static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > size_t offset,
> > const char *fmt,
> > va_list ap)
> > {
> > - return 0;
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
>
> Coding style for structured types.
OK
> > + struct iovec in_sg[2];
> > + int num;
> > +
> > + xen_9pfs_in_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> > + in_sg, &num, pdu->idx, ROUND_UP(offset + 128, 512));
> > + return v9fs_iov_vmarshal(in_sg, num, offset, 0, fmt, ap);
> > }
> >
> > static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> > @@ -61,13 +126,27 @@ static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> > const char *fmt,
> > va_list ap)
> > {
> > - return 0;
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
>
> Coding style for structured types.
OK
> > + struct iovec out_sg[2];
> > + int num;
> > +
> > + xen_9pfs_out_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> > + out_sg, &num, pdu->idx);
> > + return v9fs_iov_vunmarshal(out_sg, num, offset, 0, fmt, ap);
> > }
> >
> > static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> > struct iovec **piov,
> > unsigned int *pniov)
> > {
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> > + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
>
> Coding style for structured types.
OK
> > + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> > + int num;
> > +
> > + xen_9pfs_out_sg(ring, sg, &num, pdu->idx);
> > + *piov = sg;
> > + *pniov = num;
> > }
> >
> > static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> > @@ -75,6 +154,14 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> > unsigned int *pniov,
> > size_t size)
> > {
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> > + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
>
> Coding style for structured types.
OK :-)
> > + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> > + int num;
> > +
> > + xen_9pfs_in_sg(ring, sg, &num, pdu->idx, size);
> > + *piov = sg;
> > + *pniov = num;
> > }
> >
> > static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
>
>
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 7/9] xen/9pfs: implement in/out_iov_from_pdu and vmarshal/vunmarshal
@ 2017-03-15 21:58 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:58 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:58 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Implement xen_9pfs_init_in/out_iov_from_pdu and
> > xen_9pfs_pdu_vmarshal/vunmarshall by creating new sg pointing to the
> > data on the ring.
> >
> > This is safe as we only handle one request per ring at any given time.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 91 ++++++++++++++++++++++++++++++++++++++++++++++--
> > 1 file changed, 89 insertions(+), 2 deletions(-)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index 741dd31..d72a749 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -48,12 +48,77 @@ typedef struct Xen9pfsDev {
> > struct Xen9pfsRing *rings;
> > } Xen9pfsDev;
> >
> > +static void xen_9pfs_in_sg(struct Xen9pfsRing *ring,
>
> Coding style for structured types.
OK
> > + struct iovec *in_sg,
> > + int *num,
> > + uint32_t idx,
> > + uint32_t size)
> > +{
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > +
> > + cons = ring->intf->in_cons;
> > + prod = ring->intf->in_prod;
> > + xen_rmb();
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + if (masked_prod < masked_cons) {
> > + in_sg[0].iov_base = ring->ring.in + masked_prod;
> > + in_sg[0].iov_len = masked_cons - masked_prod;
> > + *num = 1;
> > + } else {
> > + in_sg[0].iov_base = ring->ring.in + masked_prod;
> > + in_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_prod;
> > + in_sg[1].iov_base = ring->ring.in;
> > + in_sg[1].iov_len = masked_cons;
> > + *num = 2;
> > + }
> > +}
> > +
> > +static void xen_9pfs_out_sg(struct Xen9pfsRing *ring,
>
> Coding style for structured types.
OK
> > + struct iovec *out_sg,
> > + int *num,
> > + uint32_t idx)
> > +{
> > + RING_IDX cons, prod, masked_prod, masked_cons;
> > +
> > + cons = ring->intf->out_cons;
> > + prod = ring->intf->out_prod;
> > + xen_rmb();
> > + masked_prod = xen_9pfs_mask(prod, XEN_9PFS_RING_SIZE);
> > + masked_cons = xen_9pfs_mask(cons, XEN_9PFS_RING_SIZE);
> > +
> > + if (masked_cons < masked_prod) {
> > + out_sg[0].iov_base = ring->ring.out + masked_cons;
> > + out_sg[0].iov_len = ring->out_size;
> > + *num = 1;
> > + } else {
> > + if (ring->out_size > (XEN_9PFS_RING_SIZE - masked_cons)) {
> > + out_sg[0].iov_base = ring->ring.out + masked_cons;
> > + out_sg[0].iov_len = XEN_9PFS_RING_SIZE - masked_cons;
> > + out_sg[1].iov_base = ring->ring.out;
> > + out_sg[1].iov_len = ring->out_size - (XEN_9PFS_RING_SIZE - masked_cons);
> > + *num = 2;
> > + } else {
> > + out_sg[0].iov_base = ring->ring.out + masked_cons;
> > + out_sg[0].iov_len = ring->out_size;
> > + *num = 1;
> > + }
> > + }
> > +}
> > +
> > static ssize_t xen_9pfs_pdu_vmarshal(V9fsPDU *pdu,
> > size_t offset,
> > const char *fmt,
> > va_list ap)
> > {
> > - return 0;
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
>
> Coding style for structured types.
OK
> > + struct iovec in_sg[2];
> > + int num;
> > +
> > + xen_9pfs_in_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> > + in_sg, &num, pdu->idx, ROUND_UP(offset + 128, 512));
> > + return v9fs_iov_vmarshal(in_sg, num, offset, 0, fmt, ap);
> > }
> >
> > static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> > @@ -61,13 +126,27 @@ static ssize_t xen_9pfs_pdu_vunmarshal(V9fsPDU *pdu,
> > const char *fmt,
> > va_list ap)
> > {
> > - return 0;
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
>
> Coding style for structured types.
OK
> > + struct iovec out_sg[2];
> > + int num;
> > +
> > + xen_9pfs_out_sg(&xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings],
> > + out_sg, &num, pdu->idx);
> > + return v9fs_iov_vunmarshal(out_sg, num, offset, 0, fmt, ap);
> > }
> >
> > static void xen_9pfs_init_out_iov_from_pdu(V9fsPDU *pdu,
> > struct iovec **piov,
> > unsigned int *pniov)
> > {
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> > + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
>
> Coding style for structured types.
OK
> > + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> > + int num;
> > +
> > + xen_9pfs_out_sg(ring, sg, &num, pdu->idx);
> > + *piov = sg;
> > + *pniov = num;
> > }
> >
> > static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> > @@ -75,6 +154,14 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> > unsigned int *pniov,
> > size_t size)
> > {
> > + struct Xen9pfsDev *xen_9pfs = container_of(pdu->s, struct Xen9pfsDev, state);
> > + struct Xen9pfsRing *ring = &xen_9pfs->rings[pdu->tag % xen_9pfs->num_rings];
>
> Coding style for structured types.
OK :-)
> > + struct iovec *sg = g_malloc0(sizeof(*sg)*2);
> > + int num;
> > +
> > + xen_9pfs_in_sg(ring, sg, &num, pdu->idx, size);
> > + *piov = sg;
> > + *pniov = num;
> > }
> >
> > static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
>
>
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* [Qemu-devel] [PATCH v2 8/9] xen/9pfs: send responses back to the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:55 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross, Aneesh Kumar K.V
Once a request is completed, xen_9pfs_push_and_notify gets called. In
xen_9pfs_push_and_notify, update the indexes (data has already been
copied to the sg by the common code) and send a notification to the
frontend.
Schedule the bottom-half to check if we already have any other requests
pending.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index d72a749..fed369f 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -166,6 +166,22 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
{
+ RING_IDX prod;
+ struct Xen9pfsDev *priv = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct Xen9pfsRing *ring = &priv->rings[pdu->tag % priv->num_rings];
+
+ ring->intf->out_cons = ring->out_cons;
+ xen_wmb();
+
+ prod = ring->intf->in_prod;
+ xen_rmb();
+ ring->intf->in_prod = prod + pdu->size;
+ xen_wmb();
+
+ ring->inprogress = false;
+ xenevtchn_notify(ring->evtchndev, ring->local_port);
+
+ qemu_bh_schedule(ring->bh);
}
static const struct V9fsTransport xen_9p_transport = {
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 8/9] xen/9pfs: send responses back to the frontend
@ 2017-03-13 23:55 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:55 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
Once a request is completed, xen_9pfs_push_and_notify gets called. In
xen_9pfs_push_and_notify, update the indexes (data has already been
copied to the sg by the common code) and send a notification to the
frontend.
Schedule the bottom-half to check if we already have any other requests
pending.
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/xen-9p-backend.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index d72a749..fed369f 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -166,6 +166,22 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
{
+ RING_IDX prod;
+ struct Xen9pfsDev *priv = container_of(pdu->s, struct Xen9pfsDev, state);
+ struct Xen9pfsRing *ring = &priv->rings[pdu->tag % priv->num_rings];
+
+ ring->intf->out_cons = ring->out_cons;
+ xen_wmb();
+
+ prod = ring->intf->in_prod;
+ xen_rmb();
+ ring->intf->in_prod = prod + pdu->size;
+ xen_wmb();
+
+ ring->inprogress = false;
+ xenevtchn_notify(ring->evtchndev, ring->local_port);
+
+ qemu_bh_schedule(ring->bh);
}
static const struct V9fsTransport xen_9p_transport = {
--
1.9.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 8/9] xen/9pfs: send responses back to the frontend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-15 10:59 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 10:59 UTC (permalink / raw)
To: Stefano Stabellini
Cc: qemu-devel, xen-devel, anthony.perard, Stefano Stabellini,
jgross, Aneesh Kumar K.V
[-- Attachment #1: Type: text/plain, Size: 1667 bytes --]
On Mon, 13 Mar 2017 16:55:59 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Once a request is completed, xen_9pfs_push_and_notify gets called. In
> xen_9pfs_push_and_notify, update the indexes (data has already been
> copied to the sg by the common code) and send a notification to the
> frontend.
>
> Schedule the bottom-half to check if we already have any other requests
> pending.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index d72a749..fed369f 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -166,6 +166,22 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
>
> static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> {
> + RING_IDX prod;
> + struct Xen9pfsDev *priv = container_of(pdu->s, struct Xen9pfsDev, state);
> + struct Xen9pfsRing *ring = &priv->rings[pdu->tag % priv->num_rings];
> +
Coding style for structured types.
> + ring->intf->out_cons = ring->out_cons;
> + xen_wmb();
> +
> + prod = ring->intf->in_prod;
> + xen_rmb();
> + ring->intf->in_prod = prod + pdu->size;
> + xen_wmb();
> +
> + ring->inprogress = false;
> + xenevtchn_notify(ring->evtchndev, ring->local_port);
> +
> + qemu_bh_schedule(ring->bh);
> }
>
> static const struct V9fsTransport xen_9p_transport = {
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^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 8/9] xen/9pfs: send responses back to the frontend
@ 2017-03-15 10:59 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 10:59 UTC (permalink / raw)
To: Stefano Stabellini
Cc: jgross, qemu-devel, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
[-- Attachment #1.1: Type: text/plain, Size: 1667 bytes --]
On Mon, 13 Mar 2017 16:55:59 -0700
Stefano Stabellini <sstabellini@kernel.org> wrote:
> Once a request is completed, xen_9pfs_push_and_notify gets called. In
> xen_9pfs_push_and_notify, update the indexes (data has already been
> copied to the sg by the common code) and send a notification to the
> frontend.
>
> Schedule the bottom-half to check if we already have any other requests
> pending.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: anthony.perard@citrix.com
> CC: jgross@suse.com
> CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> CC: Greg Kurz <groug@kaod.org>
> ---
> hw/9pfs/xen-9p-backend.c | 16 ++++++++++++++++
> 1 file changed, 16 insertions(+)
>
> diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> index d72a749..fed369f 100644
> --- a/hw/9pfs/xen-9p-backend.c
> +++ b/hw/9pfs/xen-9p-backend.c
> @@ -166,6 +166,22 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
>
> static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> {
> + RING_IDX prod;
> + struct Xen9pfsDev *priv = container_of(pdu->s, struct Xen9pfsDev, state);
> + struct Xen9pfsRing *ring = &priv->rings[pdu->tag % priv->num_rings];
> +
Coding style for structured types.
> + ring->intf->out_cons = ring->out_cons;
> + xen_wmb();
> +
> + prod = ring->intf->in_prod;
> + xen_rmb();
> + ring->intf->in_prod = prod + pdu->size;
> + xen_wmb();
> +
> + ring->inprogress = false;
> + xenevtchn_notify(ring->evtchndev, ring->local_port);
> +
> + qemu_bh_schedule(ring->bh);
> }
>
> static const struct V9fsTransport xen_9p_transport = {
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_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [Qemu-devel] [PATCH v2 8/9] xen/9pfs: send responses back to the frontend
2017-03-15 10:59 ` Greg Kurz
@ 2017-03-15 21:59 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:59 UTC (permalink / raw)
To: Greg Kurz
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard,
Stefano Stabellini, jgross, Aneesh Kumar K.V
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:59 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Once a request is completed, xen_9pfs_push_and_notify gets called. In
> > xen_9pfs_push_and_notify, update the indexes (data has already been
> > copied to the sg by the common code) and send a notification to the
> > frontend.
> >
> > Schedule the bottom-half to check if we already have any other requests
> > pending.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 16 ++++++++++++++++
> > 1 file changed, 16 insertions(+)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index d72a749..fed369f 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -166,6 +166,22 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> >
> > static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> > {
> > + RING_IDX prod;
> > + struct Xen9pfsDev *priv = container_of(pdu->s, struct Xen9pfsDev, state);
> > + struct Xen9pfsRing *ring = &priv->rings[pdu->tag % priv->num_rings];
> > +
>
> Coding style for structured types.
Yep
> > + ring->intf->out_cons = ring->out_cons;
> > + xen_wmb();
> > +
> > + prod = ring->intf->in_prod;
> > + xen_rmb();
> > + ring->intf->in_prod = prod + pdu->size;
> > + xen_wmb();
> > +
> > + ring->inprogress = false;
> > + xenevtchn_notify(ring->evtchndev, ring->local_port);
> > +
> > + qemu_bh_schedule(ring->bh);
> > }
> >
> > static const struct V9fsTransport xen_9p_transport = {
>
>
^ permalink raw reply [flat|nested] 72+ messages in thread* Re: [PATCH v2 8/9] xen/9pfs: send responses back to the frontend
@ 2017-03-15 21:59 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 21:59 UTC (permalink / raw)
To: Greg Kurz
Cc: jgross, Stefano Stabellini, qemu-devel, Stefano Stabellini,
Aneesh Kumar K.V, anthony.perard, xen-devel
On Wed, 15 Mar 2017, Greg Kurz wrote:
> On Mon, 13 Mar 2017 16:55:59 -0700
> Stefano Stabellini <sstabellini@kernel.org> wrote:
>
> > Once a request is completed, xen_9pfs_push_and_notify gets called. In
> > xen_9pfs_push_and_notify, update the indexes (data has already been
> > copied to the sg by the common code) and send a notification to the
> > frontend.
> >
> > Schedule the bottom-half to check if we already have any other requests
> > pending.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: anthony.perard@citrix.com
> > CC: jgross@suse.com
> > CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
> > CC: Greg Kurz <groug@kaod.org>
> > ---
> > hw/9pfs/xen-9p-backend.c | 16 ++++++++++++++++
> > 1 file changed, 16 insertions(+)
> >
> > diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
> > index d72a749..fed369f 100644
> > --- a/hw/9pfs/xen-9p-backend.c
> > +++ b/hw/9pfs/xen-9p-backend.c
> > @@ -166,6 +166,22 @@ static void xen_9pfs_init_in_iov_from_pdu(V9fsPDU *pdu,
> >
> > static void xen_9pfs_push_and_notify(V9fsPDU *pdu)
> > {
> > + RING_IDX prod;
> > + struct Xen9pfsDev *priv = container_of(pdu->s, struct Xen9pfsDev, state);
> > + struct Xen9pfsRing *ring = &priv->rings[pdu->tag % priv->num_rings];
> > +
>
> Coding style for structured types.
Yep
> > + ring->intf->out_cons = ring->out_cons;
> > + xen_wmb();
> > +
> > + prod = ring->intf->in_prod;
> > + xen_rmb();
> > + ring->intf->in_prod = prod + pdu->size;
> > + xen_wmb();
> > +
> > + ring->inprogress = false;
> > + xenevtchn_notify(ring->evtchndev, ring->local_port);
> > +
> > + qemu_bh_schedule(ring->bh);
> > }
> >
> > static const struct V9fsTransport xen_9p_transport = {
>
>
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* [Qemu-devel] [PATCH v2 9/9] xen/9pfs: build and register Xen 9pfs backend
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-13 23:56 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:56 UTC (permalink / raw)
To: qemu-devel
Cc: xen-devel, sstabellini, anthony.perard, groug,
Stefano Stabellini, jgross, Aneesh Kumar K.V
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/Makefile.objs | 1 +
hw/xen/xen_backend.c | 3 +++
include/hw/xen/xen_backend.h | 3 +++
3 files changed, 7 insertions(+)
diff --git a/hw/9pfs/Makefile.objs b/hw/9pfs/Makefile.objs
index da0ae0c..673f9f9 100644
--- a/hw/9pfs/Makefile.objs
+++ b/hw/9pfs/Makefile.objs
@@ -5,5 +5,6 @@ common-obj-y += coth.o cofs.o codir.o cofile.o
common-obj-y += coxattr.o 9p-synth.o
common-obj-$(CONFIG_OPEN_BY_HANDLE) += 9p-handle.o
common-obj-y += 9p-proxy.o
+common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
obj-y += virtio-9p-device.o
diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c
index 6c21c37..fe737e9 100644
--- a/hw/xen/xen_backend.c
+++ b/hw/xen/xen_backend.c
@@ -585,6 +585,9 @@ void xen_be_register_common(void)
xen_be_register("console", &xen_console_ops);
xen_be_register("vkbd", &xen_kbdmouse_ops);
xen_be_register("qdisk", &xen_blkdev_ops);
+#ifdef CONFIG_VIRTFS
+ xen_be_register("9pfs", &xen_9pfs_ops);
+#endif
#ifdef CONFIG_USB_LIBUSB
xen_be_register("qusb", &xen_usb_ops);
#endif
diff --git a/include/hw/xen/xen_backend.h b/include/hw/xen/xen_backend.h
index 4f4799a..7b72f1a 100644
--- a/include/hw/xen/xen_backend.h
+++ b/include/hw/xen/xen_backend.h
@@ -49,6 +49,9 @@ extern struct XenDevOps xen_console_ops; /* xen_console.c */
extern struct XenDevOps xen_kbdmouse_ops; /* xen_framebuffer.c */
extern struct XenDevOps xen_framebuffer_ops; /* xen_framebuffer.c */
extern struct XenDevOps xen_blkdev_ops; /* xen_disk.c */
+#ifdef CONFIG_VIRTFS
+extern struct XenDevOps xen_9pfs_ops; /* xen-9p-backend.c */
+#endif
extern struct XenDevOps xen_netdev_ops; /* xen_nic.c */
#ifdef CONFIG_USB_LIBUSB
extern struct XenDevOps xen_usb_ops; /* xen-usb.c */
--
1.9.1
^ permalink raw reply related [flat|nested] 72+ messages in thread* [PATCH v2 9/9] xen/9pfs: build and register Xen 9pfs backend
@ 2017-03-13 23:56 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-13 23:56 UTC (permalink / raw)
To: qemu-devel
Cc: jgross, sstabellini, groug, Stefano Stabellini, Aneesh Kumar K.V,
anthony.perard, xen-devel
Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
CC: anthony.perard@citrix.com
CC: jgross@suse.com
CC: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
CC: Greg Kurz <groug@kaod.org>
---
hw/9pfs/Makefile.objs | 1 +
hw/xen/xen_backend.c | 3 +++
include/hw/xen/xen_backend.h | 3 +++
3 files changed, 7 insertions(+)
diff --git a/hw/9pfs/Makefile.objs b/hw/9pfs/Makefile.objs
index da0ae0c..673f9f9 100644
--- a/hw/9pfs/Makefile.objs
+++ b/hw/9pfs/Makefile.objs
@@ -5,5 +5,6 @@ common-obj-y += coth.o cofs.o codir.o cofile.o
common-obj-y += coxattr.o 9p-synth.o
common-obj-$(CONFIG_OPEN_BY_HANDLE) += 9p-handle.o
common-obj-y += 9p-proxy.o
+common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
obj-y += virtio-9p-device.o
diff --git a/hw/xen/xen_backend.c b/hw/xen/xen_backend.c
index 6c21c37..fe737e9 100644
--- a/hw/xen/xen_backend.c
+++ b/hw/xen/xen_backend.c
@@ -585,6 +585,9 @@ void xen_be_register_common(void)
xen_be_register("console", &xen_console_ops);
xen_be_register("vkbd", &xen_kbdmouse_ops);
xen_be_register("qdisk", &xen_blkdev_ops);
+#ifdef CONFIG_VIRTFS
+ xen_be_register("9pfs", &xen_9pfs_ops);
+#endif
#ifdef CONFIG_USB_LIBUSB
xen_be_register("qusb", &xen_usb_ops);
#endif
diff --git a/include/hw/xen/xen_backend.h b/include/hw/xen/xen_backend.h
index 4f4799a..7b72f1a 100644
--- a/include/hw/xen/xen_backend.h
+++ b/include/hw/xen/xen_backend.h
@@ -49,6 +49,9 @@ extern struct XenDevOps xen_console_ops; /* xen_console.c */
extern struct XenDevOps xen_kbdmouse_ops; /* xen_framebuffer.c */
extern struct XenDevOps xen_framebuffer_ops; /* xen_framebuffer.c */
extern struct XenDevOps xen_blkdev_ops; /* xen_disk.c */
+#ifdef CONFIG_VIRTFS
+extern struct XenDevOps xen_9pfs_ops; /* xen-9p-backend.c */
+#endif
extern struct XenDevOps xen_netdev_ops; /* xen_nic.c */
#ifdef CONFIG_USB_LIBUSB
extern struct XenDevOps xen_usb_ops; /* xen-usb.c */
--
1.9.1
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
2017-03-13 23:55 ` Stefano Stabellini
@ 2017-03-14 10:02 ` Paolo Bonzini
-1 siblings, 0 replies; 72+ messages in thread
From: Paolo Bonzini @ 2017-03-14 10:02 UTC (permalink / raw)
To: Stefano Stabellini, qemu-devel
Cc: xen-devel, anthony.perard, groug, Stefano Stabellini,
peter.maydell, rth, stefanha
On 14/03/2017 00:55, Stefano Stabellini wrote:
> CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> regardless of the chosen targets. As a consequence, Xen backends can be
> enabled even on targets that don't support Xen.
>
> Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> support Xen.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: groug@kaod.org
> CC: groug@kaod.org
> CC: pbonzini@redhat.com
> CC: peter.maydell@linaro.org
> CC: rth@twiddle.net
> CC: stefanha@redhat.com
> ---
> configure | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/configure b/configure
> index 6c21975..6d8f752 100755
> --- a/configure
> +++ b/configure
> @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> fi
> if test "$xen" = "yes" ; then
> - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> if test "$xen_pv_domain_build" = "yes" ; then
> echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> @@ -6028,6 +6027,7 @@ case "$target_name" in
> i386|x86_64)
> if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> echo "CONFIG_XEN=y" >> $config_target_mak
> + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> if test "$xen_pci_passthrough" = yes; then
> echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> fi
>
This messes up a bit the way xen_nic.o and friends are compiled, I
think, because they are common-obj-y but they are only found when
compiling in the target subdirectories. So you end up building
x86_64-softmmu/../hw/net/xen_nic.o
If you're unlucky, I believe this can lead to a link failure where a
target is building xen_nic.o, while the other tries to link to a
partially written object file.
I think the files should be changed from
common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN). Then you
add to Makefile:
CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
+CONFIG_XEN := $(CONFIG_XEN_BACKEND)
CONFIG_ALL=y
-include config-all-devices.mak
-include config-all-disas.mak
The Makefile change ensures that they are built before descending in the
target-specific directories. The Makefile.objs change ensures that Xen
backends are not enabled on targets that support Xen.
Paolo
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
@ 2017-03-14 10:02 ` Paolo Bonzini
0 siblings, 0 replies; 72+ messages in thread
From: Paolo Bonzini @ 2017-03-14 10:02 UTC (permalink / raw)
To: Stefano Stabellini, qemu-devel
Cc: peter.maydell, groug, Stefano Stabellini, stefanha,
anthony.perard, xen-devel, rth
On 14/03/2017 00:55, Stefano Stabellini wrote:
> CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> regardless of the chosen targets. As a consequence, Xen backends can be
> enabled even on targets that don't support Xen.
>
> Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> support Xen.
>
> Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> CC: groug@kaod.org
> CC: groug@kaod.org
> CC: pbonzini@redhat.com
> CC: peter.maydell@linaro.org
> CC: rth@twiddle.net
> CC: stefanha@redhat.com
> ---
> configure | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/configure b/configure
> index 6c21975..6d8f752 100755
> --- a/configure
> +++ b/configure
> @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> fi
> if test "$xen" = "yes" ; then
> - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> if test "$xen_pv_domain_build" = "yes" ; then
> echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> @@ -6028,6 +6027,7 @@ case "$target_name" in
> i386|x86_64)
> if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> echo "CONFIG_XEN=y" >> $config_target_mak
> + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> if test "$xen_pci_passthrough" = yes; then
> echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> fi
>
This messes up a bit the way xen_nic.o and friends are compiled, I
think, because they are common-obj-y but they are only found when
compiling in the target subdirectories. So you end up building
x86_64-softmmu/../hw/net/xen_nic.o
If you're unlucky, I believe this can lead to a link failure where a
target is building xen_nic.o, while the other tries to link to a
partially written object file.
I think the files should be changed from
common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN). Then you
add to Makefile:
CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
+CONFIG_XEN := $(CONFIG_XEN_BACKEND)
CONFIG_ALL=y
-include config-all-devices.mak
-include config-all-disas.mak
The Makefile change ensures that they are built before descending in the
target-specific directories. The Makefile.objs change ensures that Xen
backends are not enabled on targets that support Xen.
Paolo
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
2017-03-14 10:02 ` Paolo Bonzini
@ 2017-03-14 19:07 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 19:07 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Stefano Stabellini, qemu-devel, xen-devel, anthony.perard, groug,
Stefano Stabellini, peter.maydell, rth, stefanha
On Tue, 14 Mar 2017, Paolo Bonzini wrote:
> On 14/03/2017 00:55, Stefano Stabellini wrote:
> > CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> > regardless of the chosen targets. As a consequence, Xen backends can be
> > enabled even on targets that don't support Xen.
> >
> > Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> > support Xen.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: groug@kaod.org
> > CC: groug@kaod.org
> > CC: pbonzini@redhat.com
> > CC: peter.maydell@linaro.org
> > CC: rth@twiddle.net
> > CC: stefanha@redhat.com
> > ---
> > configure | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/configure b/configure
> > index 6c21975..6d8f752 100755
> > --- a/configure
> > +++ b/configure
> > @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> > echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> > fi
> > if test "$xen" = "yes" ; then
> > - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> > echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> > if test "$xen_pv_domain_build" = "yes" ; then
> > echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> > @@ -6028,6 +6027,7 @@ case "$target_name" in
> > i386|x86_64)
> > if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> > echo "CONFIG_XEN=y" >> $config_target_mak
> > + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> > if test "$xen_pci_passthrough" = yes; then
> > echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> > fi
> >
>
> This messes up a bit the way xen_nic.o and friends are compiled, I
> think, because they are common-obj-y but they are only found when
> compiling in the target subdirectories. So you end up building
> x86_64-softmmu/../hw/net/xen_nic.o
>
> If you're unlucky, I believe this can lead to a link failure where a
> target is building xen_nic.o, while the other tries to link to a
> partially written object file.
>
> I think the files should be changed from
> common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN).
>
> The Makefile.objs change ensures that Xen backends are not enabled on
> targets that support Xen.
Actually I thought about doing that instead of the configure change. It
makes sense to me.
> Then you add to Makefile:
>
> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> CONFIG_ALL=y
> -include config-all-devices.mak
> -include config-all-disas.mak
>
> The Makefile change ensures that they are built before descending in the
> target-specific directories.
But I don't understand this. Please correct me if I am wrong, but this
change looks like it would end up setting CONFIG_XEN every time that
CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
would end up setting CONFIG_XEN whenever the host supports Xen, even for
non-x86 and non-ARM targets. What am I missing?
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
@ 2017-03-14 19:07 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 19:07 UTC (permalink / raw)
To: Paolo Bonzini
Cc: peter.maydell, Stefano Stabellini, qemu-devel, groug,
Stefano Stabellini, stefanha, anthony.perard, xen-devel, rth
On Tue, 14 Mar 2017, Paolo Bonzini wrote:
> On 14/03/2017 00:55, Stefano Stabellini wrote:
> > CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> > regardless of the chosen targets. As a consequence, Xen backends can be
> > enabled even on targets that don't support Xen.
> >
> > Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> > support Xen.
> >
> > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > CC: groug@kaod.org
> > CC: groug@kaod.org
> > CC: pbonzini@redhat.com
> > CC: peter.maydell@linaro.org
> > CC: rth@twiddle.net
> > CC: stefanha@redhat.com
> > ---
> > configure | 2 +-
> > 1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/configure b/configure
> > index 6c21975..6d8f752 100755
> > --- a/configure
> > +++ b/configure
> > @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> > echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> > fi
> > if test "$xen" = "yes" ; then
> > - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> > echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> > if test "$xen_pv_domain_build" = "yes" ; then
> > echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> > @@ -6028,6 +6027,7 @@ case "$target_name" in
> > i386|x86_64)
> > if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> > echo "CONFIG_XEN=y" >> $config_target_mak
> > + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> > if test "$xen_pci_passthrough" = yes; then
> > echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> > fi
> >
>
> This messes up a bit the way xen_nic.o and friends are compiled, I
> think, because they are common-obj-y but they are only found when
> compiling in the target subdirectories. So you end up building
> x86_64-softmmu/../hw/net/xen_nic.o
>
> If you're unlucky, I believe this can lead to a link failure where a
> target is building xen_nic.o, while the other tries to link to a
> partially written object file.
>
> I think the files should be changed from
> common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN).
>
> The Makefile.objs change ensures that Xen backends are not enabled on
> targets that support Xen.
Actually I thought about doing that instead of the configure change. It
makes sense to me.
> Then you add to Makefile:
>
> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> CONFIG_ALL=y
> -include config-all-devices.mak
> -include config-all-disas.mak
>
> The Makefile change ensures that they are built before descending in the
> target-specific directories.
But I don't understand this. Please correct me if I am wrong, but this
change looks like it would end up setting CONFIG_XEN every time that
CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
would end up setting CONFIG_XEN whenever the host supports Xen, even for
non-x86 and non-ARM targets. What am I missing?
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
2017-03-14 19:07 ` Stefano Stabellini
@ 2017-03-14 20:23 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 20:23 UTC (permalink / raw)
To: Stefano Stabellini
Cc: Paolo Bonzini, qemu-devel, xen-devel, anthony.perard, groug,
Stefano Stabellini, peter.maydell, rth, stefanha
On Tue, 14 Mar 2017, Stefano Stabellini wrote:
> On Tue, 14 Mar 2017, Paolo Bonzini wrote:
> > On 14/03/2017 00:55, Stefano Stabellini wrote:
> > > CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> > > regardless of the chosen targets. As a consequence, Xen backends can be
> > > enabled even on targets that don't support Xen.
> > >
> > > Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> > > support Xen.
> > >
> > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > CC: groug@kaod.org
> > > CC: groug@kaod.org
> > > CC: pbonzini@redhat.com
> > > CC: peter.maydell@linaro.org
> > > CC: rth@twiddle.net
> > > CC: stefanha@redhat.com
> > > ---
> > > configure | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/configure b/configure
> > > index 6c21975..6d8f752 100755
> > > --- a/configure
> > > +++ b/configure
> > > @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> > > echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> > > fi
> > > if test "$xen" = "yes" ; then
> > > - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> > > echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> > > if test "$xen_pv_domain_build" = "yes" ; then
> > > echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> > > @@ -6028,6 +6027,7 @@ case "$target_name" in
> > > i386|x86_64)
> > > if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> > > echo "CONFIG_XEN=y" >> $config_target_mak
> > > + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> > > if test "$xen_pci_passthrough" = yes; then
> > > echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> > > fi
> > >
> >
> > This messes up a bit the way xen_nic.o and friends are compiled, I
> > think, because they are common-obj-y but they are only found when
> > compiling in the target subdirectories. So you end up building
> > x86_64-softmmu/../hw/net/xen_nic.o
> >
> > If you're unlucky, I believe this can lead to a link failure where a
> > target is building xen_nic.o, while the other tries to link to a
> > partially written object file.
> >
> > I think the files should be changed from
> > common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN).
> >
> > The Makefile.objs change ensures that Xen backends are not enabled on
> > targets that support Xen.
>
> Actually I thought about doing that instead of the configure change. It
> makes sense to me.
>
>
> > Then you add to Makefile:
> >
> > CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> > CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> > +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> > CONFIG_ALL=y
> > -include config-all-devices.mak
> > -include config-all-disas.mak
> >
> > The Makefile change ensures that they are built before descending in the
> > target-specific directories.
>
> But I don't understand this. Please correct me if I am wrong, but this
> change looks like it would end up setting CONFIG_XEN every time that
> CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
> would end up setting CONFIG_XEN whenever the host supports Xen, even for
> non-x86 and non-ARM targets. What am I missing?
FYI I made the following changes:
diff --git a/Makefile b/Makefile
index 1c4c04f..b246138 100644
--- a/Makefile
+++ b/Makefile
@@ -26,6 +26,7 @@ endif
CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
+CONFIG_XEN := $(CONFIG_XEN_BACKEND)
CONFIG_ALL=y
-include config-all-devices.mak
-include config-all-disas.mak
diff --git a/hw/block/Makefile.objs b/hw/block/Makefile.objs
index d4c3ab7..e0ed980 100644
--- a/hw/block/Makefile.objs
+++ b/hw/block/Makefile.objs
@@ -4,7 +4,7 @@ common-obj-$(CONFIG_SSI_M25P80) += m25p80.o
common-obj-$(CONFIG_NAND) += nand.o
common-obj-$(CONFIG_PFLASH_CFI01) += pflash_cfi01.o
common-obj-$(CONFIG_PFLASH_CFI02) += pflash_cfi02.o
-common-obj-$(CONFIG_XEN_BACKEND) += xen_disk.o
+common-obj-$(CONFIG_XEN) += xen_disk.o
common-obj-$(CONFIG_ECC) += ecc.o
common-obj-$(CONFIG_ONENAND) += onenand.o
common-obj-$(CONFIG_NVME_PCI) += nvme.o
diff --git a/hw/char/Makefile.objs b/hw/char/Makefile.objs
index 6ea76fe..725fdc4 100644
--- a/hw/char/Makefile.objs
+++ b/hw/char/Makefile.objs
@@ -7,7 +7,7 @@ common-obj-$(CONFIG_SERIAL_ISA) += serial-isa.o
common-obj-$(CONFIG_SERIAL_PCI) += serial-pci.o
common-obj-$(CONFIG_VIRTIO) += virtio-console.o
common-obj-$(CONFIG_XILINX) += xilinx_uartlite.o
-common-obj-$(CONFIG_XEN_BACKEND) += xen_console.o
+common-obj-$(CONFIG_XEN) += xen_console.o
common-obj-$(CONFIG_CADENCE) += cadence_uart.o
obj-$(CONFIG_EXYNOS4) += exynos4210_uart.o
diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs
index 063889b..3d02e8b 100644
--- a/hw/display/Makefile.objs
+++ b/hw/display/Makefile.objs
@@ -5,7 +5,7 @@ common-obj-$(CONFIG_JAZZ_LED) += jazz_led.o
common-obj-$(CONFIG_PL110) += pl110.o
common-obj-$(CONFIG_SSD0303) += ssd0303.o
common-obj-$(CONFIG_SSD0323) += ssd0323.o
-common-obj-$(CONFIG_XEN_BACKEND) += xenfb.o
+common-obj-$(CONFIG_XEN) += xenfb.o
common-obj-$(CONFIG_VGA_PCI) += vga-pci.o
common-obj-$(CONFIG_VGA_ISA) += vga-isa.o
diff --git a/hw/net/Makefile.objs b/hw/net/Makefile.objs
index 610ed3e..6a95d92 100644
--- a/hw/net/Makefile.objs
+++ b/hw/net/Makefile.objs
@@ -1,5 +1,5 @@
common-obj-$(CONFIG_DP8393X) += dp8393x.o
-common-obj-$(CONFIG_XEN_BACKEND) += xen_nic.o
+common-obj-$(CONFIG_XEN) += xen_nic.o
# PCI network cards
common-obj-$(CONFIG_NE2000_PCI) += ne2000.o
diff --git a/hw/usb/Makefile.objs b/hw/usb/Makefile.objs
index 98b5c9d..5958be8 100644
--- a/hw/usb/Makefile.objs
+++ b/hw/usb/Makefile.objs
@@ -40,5 +40,5 @@ common-obj-$(CONFIG_USB_REDIR) += redirect.o quirks.o
common-obj-y += $(patsubst %,host-%.o,$(HOST_USB))
ifeq ($(CONFIG_USB_LIBUSB),y)
-common-obj-$(CONFIG_XEN_BACKEND) += xen-usb.o
+common-obj-$(CONFIG_XEN) += xen-usb.o
endif
diff --git a/hw/xen/Makefile.objs b/hw/xen/Makefile.objs
index 591cdc2..4be3ec9 100644
--- a/hw/xen/Makefile.objs
+++ b/hw/xen/Makefile.objs
@@ -1,5 +1,5 @@
# xen backend driver support
-common-obj-$(CONFIG_XEN_BACKEND) += xen_backend.o xen_devconfig.o xen_pvdev.o
+common-obj-$(CONFIG_XEN) += xen_backend.o xen_devconfig.o xen_pvdev.o
obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen_pt.o xen_pt_config_init.o xen_pt_graphics.o xen_pt_msi.o
I applied the rest of the series and did
./configure --enable-virtfs --enable-xen; make -j5
I got the following error:
LINK aarch64-softmmu/qemu-system-aarch64
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
/local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
/local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
collect2: error: ld returned 1 exit status
make[1]: *** [qemu-system-arm] Error 1
make: *** [subdir-arm-softmmu] Error 2
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
/local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
/local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
collect2: error: ld returned 1 exit status
make[1]: *** [qemu-system-aarch64] Error 1
make: *** [subdir-aarch64-softmmu] Error 2
^ permalink raw reply related [flat|nested] 72+ messages in thread
* Re: [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
@ 2017-03-14 20:23 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-14 20:23 UTC (permalink / raw)
To: Stefano Stabellini
Cc: peter.maydell, groug, qemu-devel, Stefano Stabellini, stefanha,
xen-devel, anthony.perard, Paolo Bonzini, rth
On Tue, 14 Mar 2017, Stefano Stabellini wrote:
> On Tue, 14 Mar 2017, Paolo Bonzini wrote:
> > On 14/03/2017 00:55, Stefano Stabellini wrote:
> > > CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> > > regardless of the chosen targets. As a consequence, Xen backends can be
> > > enabled even on targets that don't support Xen.
> > >
> > > Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> > > support Xen.
> > >
> > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > CC: groug@kaod.org
> > > CC: groug@kaod.org
> > > CC: pbonzini@redhat.com
> > > CC: peter.maydell@linaro.org
> > > CC: rth@twiddle.net
> > > CC: stefanha@redhat.com
> > > ---
> > > configure | 2 +-
> > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/configure b/configure
> > > index 6c21975..6d8f752 100755
> > > --- a/configure
> > > +++ b/configure
> > > @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> > > echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> > > fi
> > > if test "$xen" = "yes" ; then
> > > - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> > > echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> > > if test "$xen_pv_domain_build" = "yes" ; then
> > > echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> > > @@ -6028,6 +6027,7 @@ case "$target_name" in
> > > i386|x86_64)
> > > if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> > > echo "CONFIG_XEN=y" >> $config_target_mak
> > > + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> > > if test "$xen_pci_passthrough" = yes; then
> > > echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> > > fi
> > >
> >
> > This messes up a bit the way xen_nic.o and friends are compiled, I
> > think, because they are common-obj-y but they are only found when
> > compiling in the target subdirectories. So you end up building
> > x86_64-softmmu/../hw/net/xen_nic.o
> >
> > If you're unlucky, I believe this can lead to a link failure where a
> > target is building xen_nic.o, while the other tries to link to a
> > partially written object file.
> >
> > I think the files should be changed from
> > common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN).
> >
> > The Makefile.objs change ensures that Xen backends are not enabled on
> > targets that support Xen.
>
> Actually I thought about doing that instead of the configure change. It
> makes sense to me.
>
>
> > Then you add to Makefile:
> >
> > CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> > CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> > +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> > CONFIG_ALL=y
> > -include config-all-devices.mak
> > -include config-all-disas.mak
> >
> > The Makefile change ensures that they are built before descending in the
> > target-specific directories.
>
> But I don't understand this. Please correct me if I am wrong, but this
> change looks like it would end up setting CONFIG_XEN every time that
> CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
> would end up setting CONFIG_XEN whenever the host supports Xen, even for
> non-x86 and non-ARM targets. What am I missing?
FYI I made the following changes:
diff --git a/Makefile b/Makefile
index 1c4c04f..b246138 100644
--- a/Makefile
+++ b/Makefile
@@ -26,6 +26,7 @@ endif
CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
+CONFIG_XEN := $(CONFIG_XEN_BACKEND)
CONFIG_ALL=y
-include config-all-devices.mak
-include config-all-disas.mak
diff --git a/hw/block/Makefile.objs b/hw/block/Makefile.objs
index d4c3ab7..e0ed980 100644
--- a/hw/block/Makefile.objs
+++ b/hw/block/Makefile.objs
@@ -4,7 +4,7 @@ common-obj-$(CONFIG_SSI_M25P80) += m25p80.o
common-obj-$(CONFIG_NAND) += nand.o
common-obj-$(CONFIG_PFLASH_CFI01) += pflash_cfi01.o
common-obj-$(CONFIG_PFLASH_CFI02) += pflash_cfi02.o
-common-obj-$(CONFIG_XEN_BACKEND) += xen_disk.o
+common-obj-$(CONFIG_XEN) += xen_disk.o
common-obj-$(CONFIG_ECC) += ecc.o
common-obj-$(CONFIG_ONENAND) += onenand.o
common-obj-$(CONFIG_NVME_PCI) += nvme.o
diff --git a/hw/char/Makefile.objs b/hw/char/Makefile.objs
index 6ea76fe..725fdc4 100644
--- a/hw/char/Makefile.objs
+++ b/hw/char/Makefile.objs
@@ -7,7 +7,7 @@ common-obj-$(CONFIG_SERIAL_ISA) += serial-isa.o
common-obj-$(CONFIG_SERIAL_PCI) += serial-pci.o
common-obj-$(CONFIG_VIRTIO) += virtio-console.o
common-obj-$(CONFIG_XILINX) += xilinx_uartlite.o
-common-obj-$(CONFIG_XEN_BACKEND) += xen_console.o
+common-obj-$(CONFIG_XEN) += xen_console.o
common-obj-$(CONFIG_CADENCE) += cadence_uart.o
obj-$(CONFIG_EXYNOS4) += exynos4210_uart.o
diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs
index 063889b..3d02e8b 100644
--- a/hw/display/Makefile.objs
+++ b/hw/display/Makefile.objs
@@ -5,7 +5,7 @@ common-obj-$(CONFIG_JAZZ_LED) += jazz_led.o
common-obj-$(CONFIG_PL110) += pl110.o
common-obj-$(CONFIG_SSD0303) += ssd0303.o
common-obj-$(CONFIG_SSD0323) += ssd0323.o
-common-obj-$(CONFIG_XEN_BACKEND) += xenfb.o
+common-obj-$(CONFIG_XEN) += xenfb.o
common-obj-$(CONFIG_VGA_PCI) += vga-pci.o
common-obj-$(CONFIG_VGA_ISA) += vga-isa.o
diff --git a/hw/net/Makefile.objs b/hw/net/Makefile.objs
index 610ed3e..6a95d92 100644
--- a/hw/net/Makefile.objs
+++ b/hw/net/Makefile.objs
@@ -1,5 +1,5 @@
common-obj-$(CONFIG_DP8393X) += dp8393x.o
-common-obj-$(CONFIG_XEN_BACKEND) += xen_nic.o
+common-obj-$(CONFIG_XEN) += xen_nic.o
# PCI network cards
common-obj-$(CONFIG_NE2000_PCI) += ne2000.o
diff --git a/hw/usb/Makefile.objs b/hw/usb/Makefile.objs
index 98b5c9d..5958be8 100644
--- a/hw/usb/Makefile.objs
+++ b/hw/usb/Makefile.objs
@@ -40,5 +40,5 @@ common-obj-$(CONFIG_USB_REDIR) += redirect.o quirks.o
common-obj-y += $(patsubst %,host-%.o,$(HOST_USB))
ifeq ($(CONFIG_USB_LIBUSB),y)
-common-obj-$(CONFIG_XEN_BACKEND) += xen-usb.o
+common-obj-$(CONFIG_XEN) += xen-usb.o
endif
diff --git a/hw/xen/Makefile.objs b/hw/xen/Makefile.objs
index 591cdc2..4be3ec9 100644
--- a/hw/xen/Makefile.objs
+++ b/hw/xen/Makefile.objs
@@ -1,5 +1,5 @@
# xen backend driver support
-common-obj-$(CONFIG_XEN_BACKEND) += xen_backend.o xen_devconfig.o xen_pvdev.o
+common-obj-$(CONFIG_XEN) += xen_backend.o xen_devconfig.o xen_pvdev.o
obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen_pt.o xen_pt_config_init.o xen_pt_graphics.o xen_pt_msi.o
I applied the rest of the series and did
./configure --enable-virtfs --enable-xen; make -j5
I got the following error:
LINK aarch64-softmmu/qemu-system-aarch64
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
/local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
/local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
collect2: error: ld returned 1 exit status
make[1]: *** [qemu-system-arm] Error 1
make: *** [subdir-arm-softmmu] Error 2
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
/local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
/local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
/local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
/local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
/local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
collect2: error: ld returned 1 exit status
make[1]: *** [qemu-system-aarch64] Error 1
make: *** [subdir-aarch64-softmmu] Error 2
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply related [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
2017-03-14 20:23 ` Stefano Stabellini
@ 2017-03-15 1:03 ` Greg Kurz
-1 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 1:03 UTC (permalink / raw)
To: Stefano Stabellini
Cc: Paolo Bonzini, qemu-devel, xen-devel, anthony.perard,
Stefano Stabellini, peter.maydell, rth, stefanha
[-- Attachment #1: Type: text/plain, Size: 10191 bytes --]
On Tue, 14 Mar 2017 13:23:09 -0700 (PDT)
Stefano Stabellini <sstabellini@kernel.org> wrote:
> On Tue, 14 Mar 2017, Stefano Stabellini wrote:
> > On Tue, 14 Mar 2017, Paolo Bonzini wrote:
> > > On 14/03/2017 00:55, Stefano Stabellini wrote:
> > > > CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> > > > regardless of the chosen targets. As a consequence, Xen backends can be
> > > > enabled even on targets that don't support Xen.
> > > >
> > > > Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> > > > support Xen.
> > > >
> > > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > > CC: groug@kaod.org
> > > > CC: groug@kaod.org
> > > > CC: pbonzini@redhat.com
> > > > CC: peter.maydell@linaro.org
> > > > CC: rth@twiddle.net
> > > > CC: stefanha@redhat.com
> > > > ---
> > > > configure | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/configure b/configure
> > > > index 6c21975..6d8f752 100755
> > > > --- a/configure
> > > > +++ b/configure
> > > > @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> > > > echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> > > > fi
> > > > if test "$xen" = "yes" ; then
> > > > - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> > > > echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> > > > if test "$xen_pv_domain_build" = "yes" ; then
> > > > echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> > > > @@ -6028,6 +6027,7 @@ case "$target_name" in
> > > > i386|x86_64)
> > > > if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> > > > echo "CONFIG_XEN=y" >> $config_target_mak
> > > > + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> > > > if test "$xen_pci_passthrough" = yes; then
> > > > echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> > > > fi
> > > >
> > >
> > > This messes up a bit the way xen_nic.o and friends are compiled, I
> > > think, because they are common-obj-y but they are only found when
> > > compiling in the target subdirectories. So you end up building
> > > x86_64-softmmu/../hw/net/xen_nic.o
> > >
> > > If you're unlucky, I believe this can lead to a link failure where a
> > > target is building xen_nic.o, while the other tries to link to a
> > > partially written object file.
> > >
> > > I think the files should be changed from
> > > common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN).
> > >
> > > The Makefile.objs change ensures that Xen backends are not enabled on
> > > targets that support Xen.
> >
> > Actually I thought about doing that instead of the configure change. It
> > makes sense to me.
> >
> >
> > > Then you add to Makefile:
> > >
> > > CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> > > CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> > > +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> > > CONFIG_ALL=y
> > > -include config-all-devices.mak
> > > -include config-all-disas.mak
> > >
> > > The Makefile change ensures that they are built before descending in the
> > > target-specific directories.
> >
> > But I don't understand this. Please correct me if I am wrong, but this
> > change looks like it would end up setting CONFIG_XEN every time that
> > CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
> > would end up setting CONFIG_XEN whenever the host supports Xen, even for
> > non-x86 and non-ARM targets. What am I missing?
>
> FYI I made the following changes:
>
> diff --git a/Makefile b/Makefile
> index 1c4c04f..b246138 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -26,6 +26,7 @@ endif
>
> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> CONFIG_ALL=y
> -include config-all-devices.mak
> -include config-all-disas.mak
> diff --git a/hw/block/Makefile.objs b/hw/block/Makefile.objs
> index d4c3ab7..e0ed980 100644
> --- a/hw/block/Makefile.objs
> +++ b/hw/block/Makefile.objs
> @@ -4,7 +4,7 @@ common-obj-$(CONFIG_SSI_M25P80) += m25p80.o
> common-obj-$(CONFIG_NAND) += nand.o
> common-obj-$(CONFIG_PFLASH_CFI01) += pflash_cfi01.o
> common-obj-$(CONFIG_PFLASH_CFI02) += pflash_cfi02.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_disk.o
> +common-obj-$(CONFIG_XEN) += xen_disk.o
> common-obj-$(CONFIG_ECC) += ecc.o
> common-obj-$(CONFIG_ONENAND) += onenand.o
> common-obj-$(CONFIG_NVME_PCI) += nvme.o
> diff --git a/hw/char/Makefile.objs b/hw/char/Makefile.objs
> index 6ea76fe..725fdc4 100644
> --- a/hw/char/Makefile.objs
> +++ b/hw/char/Makefile.objs
> @@ -7,7 +7,7 @@ common-obj-$(CONFIG_SERIAL_ISA) += serial-isa.o
> common-obj-$(CONFIG_SERIAL_PCI) += serial-pci.o
> common-obj-$(CONFIG_VIRTIO) += virtio-console.o
> common-obj-$(CONFIG_XILINX) += xilinx_uartlite.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_console.o
> +common-obj-$(CONFIG_XEN) += xen_console.o
> common-obj-$(CONFIG_CADENCE) += cadence_uart.o
>
> obj-$(CONFIG_EXYNOS4) += exynos4210_uart.o
> diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs
> index 063889b..3d02e8b 100644
> --- a/hw/display/Makefile.objs
> +++ b/hw/display/Makefile.objs
> @@ -5,7 +5,7 @@ common-obj-$(CONFIG_JAZZ_LED) += jazz_led.o
> common-obj-$(CONFIG_PL110) += pl110.o
> common-obj-$(CONFIG_SSD0303) += ssd0303.o
> common-obj-$(CONFIG_SSD0323) += ssd0323.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xenfb.o
> +common-obj-$(CONFIG_XEN) += xenfb.o
>
> common-obj-$(CONFIG_VGA_PCI) += vga-pci.o
> common-obj-$(CONFIG_VGA_ISA) += vga-isa.o
> diff --git a/hw/net/Makefile.objs b/hw/net/Makefile.objs
> index 610ed3e..6a95d92 100644
> --- a/hw/net/Makefile.objs
> +++ b/hw/net/Makefile.objs
> @@ -1,5 +1,5 @@
> common-obj-$(CONFIG_DP8393X) += dp8393x.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_nic.o
> +common-obj-$(CONFIG_XEN) += xen_nic.o
>
> # PCI network cards
> common-obj-$(CONFIG_NE2000_PCI) += ne2000.o
> diff --git a/hw/usb/Makefile.objs b/hw/usb/Makefile.objs
> index 98b5c9d..5958be8 100644
> --- a/hw/usb/Makefile.objs
> +++ b/hw/usb/Makefile.objs
> @@ -40,5 +40,5 @@ common-obj-$(CONFIG_USB_REDIR) += redirect.o quirks.o
> common-obj-y += $(patsubst %,host-%.o,$(HOST_USB))
>
> ifeq ($(CONFIG_USB_LIBUSB),y)
> -common-obj-$(CONFIG_XEN_BACKEND) += xen-usb.o
> +common-obj-$(CONFIG_XEN) += xen-usb.o
> endif
> diff --git a/hw/xen/Makefile.objs b/hw/xen/Makefile.objs
> index 591cdc2..4be3ec9 100644
> --- a/hw/xen/Makefile.objs
> +++ b/hw/xen/Makefile.objs
> @@ -1,5 +1,5 @@
> # xen backend driver support
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_backend.o xen_devconfig.o xen_pvdev.o
> +common-obj-$(CONFIG_XEN) += xen_backend.o xen_devconfig.o xen_pvdev.o
>
> obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
> obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen_pt.o xen_pt_config_init.o xen_pt_graphics.o xen_pt_msi.o
>
> I applied the rest of the series and did
>
> ./configure --enable-virtfs --enable-xen; make -j5
>
> I got the following error:
>
> LINK aarch64-softmmu/qemu-system-aarch64
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
It looks like hw/9pfs/Makefile.objs may still have:
common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
instead of:
common-obj-$(CONFIG_XEN) += xen-9p-backend.o
... which builds like a charm.
Cheers.
--
Greg
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-arm] Error 1
> make: *** [subdir-arm-softmmu] Error 2
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-aarch64] Error 1
> make: *** [subdir-aarch64-softmmu] Error 2
>
[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
@ 2017-03-15 1:03 ` Greg Kurz
0 siblings, 0 replies; 72+ messages in thread
From: Greg Kurz @ 2017-03-15 1:03 UTC (permalink / raw)
To: Stefano Stabellini
Cc: peter.maydell, qemu-devel, Stefano Stabellini, stefanha,
xen-devel, anthony.perard, Paolo Bonzini, rth
[-- Attachment #1.1: Type: text/plain, Size: 10191 bytes --]
On Tue, 14 Mar 2017 13:23:09 -0700 (PDT)
Stefano Stabellini <sstabellini@kernel.org> wrote:
> On Tue, 14 Mar 2017, Stefano Stabellini wrote:
> > On Tue, 14 Mar 2017, Paolo Bonzini wrote:
> > > On 14/03/2017 00:55, Stefano Stabellini wrote:
> > > > CONFIG_XEN_BACKEND is currently set when the host supports Xen,
> > > > regardless of the chosen targets. As a consequence, Xen backends can be
> > > > enabled even on targets that don't support Xen.
> > > >
> > > > Fix the issue by setting CONFIG_XEN_BACKEND only for targets that
> > > > support Xen.
> > > >
> > > > Signed-off-by: Stefano Stabellini <stefano@aporeto.com>
> > > > CC: groug@kaod.org
> > > > CC: groug@kaod.org
> > > > CC: pbonzini@redhat.com
> > > > CC: peter.maydell@linaro.org
> > > > CC: rth@twiddle.net
> > > > CC: stefanha@redhat.com
> > > > ---
> > > > configure | 2 +-
> > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > >
> > > > diff --git a/configure b/configure
> > > > index 6c21975..6d8f752 100755
> > > > --- a/configure
> > > > +++ b/configure
> > > > @@ -5442,7 +5442,6 @@ if test "$virglrenderer" = "yes" ; then
> > > > echo "VIRGL_LIBS=$virgl_libs" >> $config_host_mak
> > > > fi
> > > > if test "$xen" = "yes" ; then
> > > > - echo "CONFIG_XEN_BACKEND=y" >> $config_host_mak
> > > > echo "CONFIG_XEN_CTRL_INTERFACE_VERSION=$xen_ctrl_version" >> $config_host_mak
> > > > if test "$xen_pv_domain_build" = "yes" ; then
> > > > echo "CONFIG_XEN_PV_DOMAIN_BUILD=y" >> $config_host_mak
> > > > @@ -6028,6 +6027,7 @@ case "$target_name" in
> > > > i386|x86_64)
> > > > if test "$xen" = "yes" -a "$target_softmmu" = "yes" ; then
> > > > echo "CONFIG_XEN=y" >> $config_target_mak
> > > > + echo "CONFIG_XEN_BACKEND=y" >> $config_target_mak
> > > > if test "$xen_pci_passthrough" = yes; then
> > > > echo "CONFIG_XEN_PCI_PASSTHROUGH=y" >> "$config_target_mak"
> > > > fi
> > > >
> > >
> > > This messes up a bit the way xen_nic.o and friends are compiled, I
> > > think, because they are common-obj-y but they are only found when
> > > compiling in the target subdirectories. So you end up building
> > > x86_64-softmmu/../hw/net/xen_nic.o
> > >
> > > If you're unlucky, I believe this can lead to a link failure where a
> > > target is building xen_nic.o, while the other tries to link to a
> > > partially written object file.
> > >
> > > I think the files should be changed from
> > > common-obj-$(CONFIG_XEN_BACKEND) to common-obj-$(CONFIG_XEN).
> > >
> > > The Makefile.objs change ensures that Xen backends are not enabled on
> > > targets that support Xen.
> >
> > Actually I thought about doing that instead of the configure change. It
> > makes sense to me.
> >
> >
> > > Then you add to Makefile:
> > >
> > > CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> > > CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> > > +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> > > CONFIG_ALL=y
> > > -include config-all-devices.mak
> > > -include config-all-disas.mak
> > >
> > > The Makefile change ensures that they are built before descending in the
> > > target-specific directories.
> >
> > But I don't understand this. Please correct me if I am wrong, but this
> > change looks like it would end up setting CONFIG_XEN every time that
> > CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
> > would end up setting CONFIG_XEN whenever the host supports Xen, even for
> > non-x86 and non-ARM targets. What am I missing?
>
> FYI I made the following changes:
>
> diff --git a/Makefile b/Makefile
> index 1c4c04f..b246138 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -26,6 +26,7 @@ endif
>
> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> CONFIG_ALL=y
> -include config-all-devices.mak
> -include config-all-disas.mak
> diff --git a/hw/block/Makefile.objs b/hw/block/Makefile.objs
> index d4c3ab7..e0ed980 100644
> --- a/hw/block/Makefile.objs
> +++ b/hw/block/Makefile.objs
> @@ -4,7 +4,7 @@ common-obj-$(CONFIG_SSI_M25P80) += m25p80.o
> common-obj-$(CONFIG_NAND) += nand.o
> common-obj-$(CONFIG_PFLASH_CFI01) += pflash_cfi01.o
> common-obj-$(CONFIG_PFLASH_CFI02) += pflash_cfi02.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_disk.o
> +common-obj-$(CONFIG_XEN) += xen_disk.o
> common-obj-$(CONFIG_ECC) += ecc.o
> common-obj-$(CONFIG_ONENAND) += onenand.o
> common-obj-$(CONFIG_NVME_PCI) += nvme.o
> diff --git a/hw/char/Makefile.objs b/hw/char/Makefile.objs
> index 6ea76fe..725fdc4 100644
> --- a/hw/char/Makefile.objs
> +++ b/hw/char/Makefile.objs
> @@ -7,7 +7,7 @@ common-obj-$(CONFIG_SERIAL_ISA) += serial-isa.o
> common-obj-$(CONFIG_SERIAL_PCI) += serial-pci.o
> common-obj-$(CONFIG_VIRTIO) += virtio-console.o
> common-obj-$(CONFIG_XILINX) += xilinx_uartlite.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_console.o
> +common-obj-$(CONFIG_XEN) += xen_console.o
> common-obj-$(CONFIG_CADENCE) += cadence_uart.o
>
> obj-$(CONFIG_EXYNOS4) += exynos4210_uart.o
> diff --git a/hw/display/Makefile.objs b/hw/display/Makefile.objs
> index 063889b..3d02e8b 100644
> --- a/hw/display/Makefile.objs
> +++ b/hw/display/Makefile.objs
> @@ -5,7 +5,7 @@ common-obj-$(CONFIG_JAZZ_LED) += jazz_led.o
> common-obj-$(CONFIG_PL110) += pl110.o
> common-obj-$(CONFIG_SSD0303) += ssd0303.o
> common-obj-$(CONFIG_SSD0323) += ssd0323.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xenfb.o
> +common-obj-$(CONFIG_XEN) += xenfb.o
>
> common-obj-$(CONFIG_VGA_PCI) += vga-pci.o
> common-obj-$(CONFIG_VGA_ISA) += vga-isa.o
> diff --git a/hw/net/Makefile.objs b/hw/net/Makefile.objs
> index 610ed3e..6a95d92 100644
> --- a/hw/net/Makefile.objs
> +++ b/hw/net/Makefile.objs
> @@ -1,5 +1,5 @@
> common-obj-$(CONFIG_DP8393X) += dp8393x.o
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_nic.o
> +common-obj-$(CONFIG_XEN) += xen_nic.o
>
> # PCI network cards
> common-obj-$(CONFIG_NE2000_PCI) += ne2000.o
> diff --git a/hw/usb/Makefile.objs b/hw/usb/Makefile.objs
> index 98b5c9d..5958be8 100644
> --- a/hw/usb/Makefile.objs
> +++ b/hw/usb/Makefile.objs
> @@ -40,5 +40,5 @@ common-obj-$(CONFIG_USB_REDIR) += redirect.o quirks.o
> common-obj-y += $(patsubst %,host-%.o,$(HOST_USB))
>
> ifeq ($(CONFIG_USB_LIBUSB),y)
> -common-obj-$(CONFIG_XEN_BACKEND) += xen-usb.o
> +common-obj-$(CONFIG_XEN) += xen-usb.o
> endif
> diff --git a/hw/xen/Makefile.objs b/hw/xen/Makefile.objs
> index 591cdc2..4be3ec9 100644
> --- a/hw/xen/Makefile.objs
> +++ b/hw/xen/Makefile.objs
> @@ -1,5 +1,5 @@
> # xen backend driver support
> -common-obj-$(CONFIG_XEN_BACKEND) += xen_backend.o xen_devconfig.o xen_pvdev.o
> +common-obj-$(CONFIG_XEN) += xen_backend.o xen_devconfig.o xen_pvdev.o
>
> obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen-host-pci-device.o
> obj-$(CONFIG_XEN_PCI_PASSTHROUGH) += xen_pt.o xen_pt_config_init.o xen_pt_graphics.o xen_pt_msi.o
>
> I applied the rest of the series and did
>
> ./configure --enable-virtfs --enable-xen; make -j5
>
> I got the following error:
>
> LINK aarch64-softmmu/qemu-system-aarch64
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
It looks like hw/9pfs/Makefile.objs may still have:
common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
instead of:
common-obj-$(CONFIG_XEN) += xen-9p-backend.o
... which builds like a charm.
Cheers.
--
Greg
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-arm] Error 1
> make: *** [subdir-arm-softmmu] Error 2
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-aarch64] Error 1
> make: *** [subdir-aarch64-softmmu] Error 2
>
[-- Attachment #1.2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]
[-- Attachment #2: Type: text/plain, Size: 127 bytes --]
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
2017-03-14 20:23 ` Stefano Stabellini
@ 2017-03-15 7:41 ` Paolo Bonzini
-1 siblings, 0 replies; 72+ messages in thread
From: Paolo Bonzini @ 2017-03-15 7:41 UTC (permalink / raw)
To: Stefano Stabellini
Cc: peter.maydell, groug, qemu-devel, Stefano Stabellini, stefanha,
xen-devel, anthony.perard, rth
On 14/03/2017 21:23, Stefano Stabellini wrote:
> On Tue, 14 Mar 2017, Stefano Stabellini wrote:
>>> Then you add to Makefile:
>>>
>>> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
>>> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
>>> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
>>> CONFIG_ALL=y
>>> -include config-all-devices.mak
>>> -include config-all-disas.mak
>>>
>>> The Makefile change ensures that they are built before descending in the
>>> target-specific directories.
>>
>> But I don't understand this. Please correct me if I am wrong, but this
>> change looks like it would end up setting CONFIG_XEN every time that
>> CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
>> would end up setting CONFIG_XEN whenever the host supports Xen, even for
>> non-x86 and non-ARM targets. What am I missing?
This CONFIG_XEN assignment applies to the toplevel only, i.e. to files
that are built once. Targets will still take CONFIG_XEN from
config-target.mak, and it will not be set for non-x86/non-ARM targets.
This CONFIG_XEN assignment applies to files that are compiled once.
The issue you reported here:
> LINK aarch64-softmmu/qemu-system-aarch64
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
is because you need this in patch 9:
-common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
+common-obj-$(CONFIG_XEN) += xen-9p-backend.o
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-arm] Error 1
> make: *** [subdir-arm-softmmu] Error 2
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-aarch64] Error 1
> make: *** [subdir-aarch64-softmmu] Error 2
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> https://lists.xen.org/xen-devel
>
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
@ 2017-03-15 7:41 ` Paolo Bonzini
0 siblings, 0 replies; 72+ messages in thread
From: Paolo Bonzini @ 2017-03-15 7:41 UTC (permalink / raw)
To: Stefano Stabellini
Cc: peter.maydell, groug, qemu-devel, Stefano Stabellini, stefanha,
anthony.perard, xen-devel, rth
On 14/03/2017 21:23, Stefano Stabellini wrote:
> On Tue, 14 Mar 2017, Stefano Stabellini wrote:
>>> Then you add to Makefile:
>>>
>>> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
>>> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
>>> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
>>> CONFIG_ALL=y
>>> -include config-all-devices.mak
>>> -include config-all-disas.mak
>>>
>>> The Makefile change ensures that they are built before descending in the
>>> target-specific directories.
>>
>> But I don't understand this. Please correct me if I am wrong, but this
>> change looks like it would end up setting CONFIG_XEN every time that
>> CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
>> would end up setting CONFIG_XEN whenever the host supports Xen, even for
>> non-x86 and non-ARM targets. What am I missing?
This CONFIG_XEN assignment applies to the toplevel only, i.e. to files
that are built once. Targets will still take CONFIG_XEN from
config-target.mak, and it will not be set for non-x86/non-ARM targets.
This CONFIG_XEN assignment applies to files that are compiled once.
The issue you reported here:
> LINK aarch64-softmmu/qemu-system-aarch64
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
is because you need this in patch 9:
-common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
+common-obj-$(CONFIG_XEN) += xen-9p-backend.o
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-arm] Error 1
> make: *** [subdir-arm-softmmu] Error 2
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_connect':
> /local/qemu/hw/9pfs/xen-9p-backend.c:292: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:313: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:357: undefined reference to `xen_pv_printf'
> /local/qemu/hw/9pfs/xen-9p-backend.c:307: undefined reference to `xenstore_read_fe_int'
> /local/qemu/hw/9pfs/xen-9p-backend.c:362: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:363: undefined reference to `xenstore_read_be_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:366: undefined reference to `xenstore_read_fe_str'
> /local/qemu/hw/9pfs/xen-9p-backend.c:353: undefined reference to `xen_pv_printf'
> ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> /local/qemu/hw/9pfs/xen-9p-backend.c:389: undefined reference to `xenstore_write_be_int'
> collect2: error: ld returned 1 exit status
> make[1]: *** [qemu-system-aarch64] Error 1
> make: *** [subdir-aarch64-softmmu] Error 2
>
>
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xen.org
> https://lists.xen.org/xen-devel
>
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [Qemu-devel] [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
2017-03-15 7:41 ` Paolo Bonzini
@ 2017-03-15 18:42 ` Stefano Stabellini
-1 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 18:42 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Stefano Stabellini, peter.maydell, groug, qemu-devel,
Stefano Stabellini, stefanha, xen-devel, anthony.perard, rth
On Wed, 15 Mar 2017, Paolo Bonzini wrote:
> On 14/03/2017 21:23, Stefano Stabellini wrote:
> > On Tue, 14 Mar 2017, Stefano Stabellini wrote:
> >>> Then you add to Makefile:
> >>>
> >>> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> >>> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> >>> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> >>> CONFIG_ALL=y
> >>> -include config-all-devices.mak
> >>> -include config-all-disas.mak
> >>>
> >>> The Makefile change ensures that they are built before descending in the
> >>> target-specific directories.
> >>
> >> But I don't understand this. Please correct me if I am wrong, but this
> >> change looks like it would end up setting CONFIG_XEN every time that
> >> CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
> >> would end up setting CONFIG_XEN whenever the host supports Xen, even for
> >> non-x86 and non-ARM targets. What am I missing?
>
> This CONFIG_XEN assignment applies to the toplevel only, i.e. to files
> that are built once. Targets will still take CONFIG_XEN from
> config-target.mak, and it will not be set for non-x86/non-ARM targets.
> This CONFIG_XEN assignment applies to files that are compiled once.
>
> The issue you reported here:
>
> > LINK aarch64-softmmu/qemu-system-aarch64
> > ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> > /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> > /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
>
> is because you need this in patch 9:
>
> -common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
> +common-obj-$(CONFIG_XEN) += xen-9p-backend.o
>
/me shakes his head in shame.
Thank you for the explanation!
^ permalink raw reply [flat|nested] 72+ messages in thread
* Re: [PATCH v2 1/9] configure: change CONFIG_XEN_BACKEND to be a target property
@ 2017-03-15 18:42 ` Stefano Stabellini
0 siblings, 0 replies; 72+ messages in thread
From: Stefano Stabellini @ 2017-03-15 18:42 UTC (permalink / raw)
To: Paolo Bonzini
Cc: peter.maydell, Stefano Stabellini, groug, qemu-devel,
Stefano Stabellini, stefanha, anthony.perard, xen-devel, rth
On Wed, 15 Mar 2017, Paolo Bonzini wrote:
> On 14/03/2017 21:23, Stefano Stabellini wrote:
> > On Tue, 14 Mar 2017, Stefano Stabellini wrote:
> >>> Then you add to Makefile:
> >>>
> >>> CONFIG_SOFTMMU := $(if $(filter %-softmmu,$(TARGET_DIRS)),y)
> >>> CONFIG_USER_ONLY := $(if $(filter %-user,$(TARGET_DIRS)),y)
> >>> +CONFIG_XEN := $(CONFIG_XEN_BACKEND)
> >>> CONFIG_ALL=y
> >>> -include config-all-devices.mak
> >>> -include config-all-disas.mak
> >>>
> >>> The Makefile change ensures that they are built before descending in the
> >>> target-specific directories.
> >>
> >> But I don't understand this. Please correct me if I am wrong, but this
> >> change looks like it would end up setting CONFIG_XEN every time that
> >> CONFIG_XEN_BACKEND is set. Without the configure change at the top, it
> >> would end up setting CONFIG_XEN whenever the host supports Xen, even for
> >> non-x86 and non-ARM targets. What am I missing?
>
> This CONFIG_XEN assignment applies to the toplevel only, i.e. to files
> that are built once. Targets will still take CONFIG_XEN from
> config-target.mak, and it will not be set for non-x86/non-ARM targets.
> This CONFIG_XEN assignment applies to files that are compiled once.
>
> The issue you reported here:
>
> > LINK aarch64-softmmu/qemu-system-aarch64
> > ../hw/9pfs/xen-9p-backend.o: In function `xen_9pfs_alloc':
> > /local/qemu/hw/9pfs/xen-9p-backend.c:387: undefined reference to `xenstore_write_be_str'
> > /local/qemu/hw/9pfs/xen-9p-backend.c:388: undefined reference to `xenstore_write_be_int'
>
> is because you need this in patch 9:
>
> -common-obj-$(CONFIG_XEN_BACKEND) += xen-9p-backend.o
> +common-obj-$(CONFIG_XEN) += xen-9p-backend.o
>
/me shakes his head in shame.
Thank you for the explanation!
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel
^ permalink raw reply [flat|nested] 72+ messages in thread