From: David Woodhouse <dwmw2@infradead.org>
To: qemu-devel@nongnu.org
Cc: "Paolo Bonzini" <pbonzini@redhat.com>,
"Paul Durrant" <paul@xen.org>,
"Joao Martins" <joao.m.martins@oracle.com>,
"Ankur Arora" <ankur.a.arora@oracle.com>,
"Philippe Mathieu-Daudé" <philmd@linaro.org>,
"Thomas Huth" <thuth@redhat.com>,
"Alex Bennée" <alex.bennee@linaro.org>,
"Juan Quintela" <quintela@redhat.com>,
"Dr . David Alan Gilbert" <dgilbert@redhat.com>,
"Claudio Fontana" <cfontana@suse.de>,
"Julien Grall" <julien@xen.org>
Subject: [RFC PATCH v1 05/15] hw/xen: Add foreignmem operations to allow redirection to internal emulation
Date: Tue, 10 Jan 2023 12:37:44 +0000 [thread overview]
Message-ID: <20230110123754.1564465-6-dwmw2@infradead.org> (raw)
In-Reply-To: <20230110123754.1564465-1-dwmw2@infradead.org>
From: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
---
hw/char/xen_console.c | 8 ++--
hw/display/xenfb.c | 20 +++++-----
hw/xen/xen-operations.c | 63 ++++++++++++++++++++++++++++++++
include/hw/xen/xen_backend_ops.h | 26 +++++++++++++
include/hw/xen/xen_common.h | 13 -------
softmmu/globals.c | 1 +
6 files changed, 105 insertions(+), 26 deletions(-)
diff --git a/hw/char/xen_console.c b/hw/char/xen_console.c
index 19ad6c946a..e9cef3e1ef 100644
--- a/hw/char/xen_console.c
+++ b/hw/char/xen_console.c
@@ -237,9 +237,9 @@ static int con_initialise(struct XenLegacyDevice *xendev)
if (!xendev->dev) {
xen_pfn_t mfn = con->ring_ref;
- con->sring = xenforeignmemory_map(xen_fmem, con->xendev.dom,
- PROT_READ | PROT_WRITE,
- 1, &mfn, NULL);
+ con->sring = qemu_xen_foreignmem_map(con->xendev.dom, NULL,
+ PROT_READ | PROT_WRITE,
+ 1, &mfn, NULL);
} else {
con->sring = xen_be_map_grant_ref(xendev, con->ring_ref,
PROT_READ | PROT_WRITE);
@@ -269,7 +269,7 @@ static void con_disconnect(struct XenLegacyDevice *xendev)
if (con->sring) {
if (!xendev->dev) {
- xenforeignmemory_unmap(xen_fmem, con->sring, 1);
+ qemu_xen_foreignmem_unmap(con->sring, 1);
} else {
xen_be_unmap_grant_ref(xendev, con->sring, con->ring_ref);
}
diff --git a/hw/display/xenfb.c b/hw/display/xenfb.c
index 260eb38a76..2c4016fcbd 100644
--- a/hw/display/xenfb.c
+++ b/hw/display/xenfb.c
@@ -98,8 +98,9 @@ static int common_bind(struct common *c)
if (xenstore_read_fe_int(&c->xendev, "event-channel", &c->xendev.remote_port) == -1)
return -1;
- c->page = xenforeignmemory_map(xen_fmem, c->xendev.dom,
- PROT_READ | PROT_WRITE, 1, &mfn, NULL);
+ c->page = qemu_xen_foreignmem_map(c->xendev.dom, NULL,
+ PROT_READ | PROT_WRITE, 1, &mfn,
+ NULL);
if (c->page == NULL)
return -1;
@@ -115,7 +116,7 @@ static void common_unbind(struct common *c)
{
xen_pv_unbind_evtchn(&c->xendev);
if (c->page) {
- xenforeignmemory_unmap(xen_fmem, c->page, 1);
+ qemu_xen_foreignmem_unmap(c->page, 1);
c->page = NULL;
}
}
@@ -500,15 +501,16 @@ static int xenfb_map_fb(struct XenFB *xenfb)
fbmfns = g_new0(xen_pfn_t, xenfb->fbpages);
xenfb_copy_mfns(mode, n_fbdirs, pgmfns, pd);
- map = xenforeignmemory_map(xen_fmem, xenfb->c.xendev.dom,
- PROT_READ, n_fbdirs, pgmfns, NULL);
+ map = qemu_xen_foreignmem_map(xenfb->c.xendev.dom, NULL, PROT_READ,
+ n_fbdirs, pgmfns, NULL);
if (map == NULL)
goto out;
xenfb_copy_mfns(mode, xenfb->fbpages, fbmfns, map);
- xenforeignmemory_unmap(xen_fmem, map, n_fbdirs);
+ qemu_xen_foreignmem_unmap(map, n_fbdirs);
- xenfb->pixels = xenforeignmemory_map(xen_fmem, xenfb->c.xendev.dom,
- PROT_READ, xenfb->fbpages, fbmfns, NULL);
+ xenfb->pixels = qemu_xen_foreignmem_map(xenfb->c.xendev.dom, NULL,
+ PROT_READ, xenfb->fbpages,
+ fbmfns, NULL);
if (xenfb->pixels == NULL)
goto out;
@@ -927,7 +929,7 @@ static void fb_disconnect(struct XenLegacyDevice *xendev)
* Replacing the framebuffer with anonymous shared memory
* instead. This releases the guest pages and keeps qemu happy.
*/
- xenforeignmemory_unmap(xen_fmem, fb->pixels, fb->fbpages);
+ qemu_xen_foreignmem_unmap(fb->pixels, fb->fbpages);
fb->pixels = mmap(fb->pixels, fb->fbpages * XC_PAGE_SIZE,
PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANON,
-1, 0);
diff --git a/hw/xen/xen-operations.c b/hw/xen/xen-operations.c
index 73dabac8e5..4c6b305cc4 100644
--- a/hw/xen/xen-operations.c
+++ b/hw/xen/xen-operations.c
@@ -22,6 +22,7 @@
*/
#undef XC_WANT_COMPAT_EVTCHN_API
#undef XC_WANT_COMPAT_GNTTAB_API
+#undef XC_WANT_COMPAT_MAP_FOREIGN_API
#include <xenctrl.h>
@@ -56,10 +57,13 @@ typedef xc_gnttab xengnttab_handle;
#define xengnttab_map_domain_grant_refs(h, c, d, r, p) \
xc_gnttab_map_domain_grant_refs(h, c, d, r, p)
+typedef xc_interface xenforeignmemory_handle;
+
#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40701 */
#include <xenevtchn.h>
#include <xengnttab.h>
+#include <xenforeignmemory.h>
#endif
@@ -218,6 +222,64 @@ static struct gnttab_backend_ops libxengnttab_backend_ops = {
.unmap = libxengnttab_backend_unmap,
};
+#if CONFIG_XEN_CTRL_INTERFACE_VERSION < 40701
+
+static void *libxenforeignmem_backend_map(uint32_t dom, void *addr, int prot,
+ size_t pages,
+ uint64_t *pfns, int *errs)
+{
+ if (errs)
+ return xc_map_foreign_bulk(xen_xc, dom, prot, arr, err, pages);
+ else
+ return xc_map_foreign_pages(xen_xc, dom, prot, arr, pages);
+}
+
+static int libxenforeignmem_backend_unmap(void *addr, size_t pages)
+{
+ return munmap(addr, pages * XC_PAGE_SIZE);
+}
+
+#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40701 */
+
+static void *libxenforeignmem_backend_map(uint32_t dom, void *addr, int prot,
+ size_t pages,
+ uint64_t *pfns, int *errs)
+{
+ xen_pfn_t *xen_pfns;
+ void *ptr = NULL;
+
+ if (sizeof(pfns[0]) == sizeof(xen_pfn_t)) {
+ xen_pfns = (xen_pfn_t *)pfns;
+ } else {
+ int i;
+ xen_pfns = g_new0(xen_pfn_t, pages);
+ for (i = 0; i < pages; i++) {
+ xen_pfns[i] = pfns[i];
+ if (xen_pfns[i] != pfns[i]) {
+ goto out;
+ }
+ }
+ }
+ ptr = xenforeignmemory_map2(xen_fmem, dom, addr, prot, 0, pages, xen_pfns, errs);
+ out:
+ if ((void *)xen_pfns != (void *)pfns) {
+ g_free(xen_pfns);
+ }
+ return ptr;
+}
+
+static int libxenforeignmem_backend_unmap(void *addr, size_t pages)
+{
+ return xenforeignmemory_unmap(xen_fmem, addr, pages);
+}
+
+#endif
+
+struct foreignmem_backend_ops libxenforeignmem_backend_ops = {
+ .map = libxenforeignmem_backend_map,
+ .unmap = libxenforeignmem_backend_unmap,
+};
+
void setup_xen_backend_ops(void)
{
#if CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40800
@@ -232,4 +294,5 @@ void setup_xen_backend_ops(void)
#endif
xen_evtchn_ops = &libxenevtchn_backend_ops;
xen_gnttab_ops = &libxengnttab_backend_ops;
+ xen_foreignmem_ops = &libxenforeignmem_backend_ops;
}
diff --git a/include/hw/xen/xen_backend_ops.h b/include/hw/xen/xen_backend_ops.h
index 3e9392d3fa..5bbe7bbc01 100644
--- a/include/hw/xen/xen_backend_ops.h
+++ b/include/hw/xen/xen_backend_ops.h
@@ -207,6 +207,32 @@ static inline int qemu_xen_gnttab_unmap(xengnttab_handle *xgt,
return xen_gnttab_ops->unmap(xgt, start_address, refs, count);
}
+struct foreignmem_backend_ops {
+ void *(*map)(uint32_t dom, void *addr, int prot, size_t pages,
+ uint64_t *pfns, int *errs);
+ int (*unmap)(void *addr, size_t pages);
+};
+
+extern struct foreignmem_backend_ops *xen_foreignmem_ops;
+
+static inline void *qemu_xen_foreignmem_map(uint32_t dom, void *addr, int prot,
+ size_t pages,
+ uint64_t *pfns, int *errs)
+{
+ if (!xen_foreignmem_ops) {
+ return NULL;
+ }
+ return xen_foreignmem_ops->map(dom, addr, prot, pages, pfns, errs);
+}
+
+static inline int qemu_xen_foreignmem_unmap(void *addr, size_t pages)
+{
+ if (!xen_foreignmem_ops) {
+ return -ENOSYS;
+ }
+ return xen_foreignmem_ops->unmap(addr, pages);
+}
+
void setup_xen_backend_ops(void);
#endif /* QEMU_XEN_BACKEND_OPS_H */
diff --git a/include/hw/xen/xen_common.h b/include/hw/xen/xen_common.h
index 1a334e498e..4440c2b245 100644
--- a/include/hw/xen/xen_common.h
+++ b/include/hw/xen/xen_common.h
@@ -32,19 +32,6 @@ typedef xc_interface xenforeignmemory_handle;
#define xenforeignmemory_open(l, f) xen_xc
#define xenforeignmemory_close(h)
-static inline void *xenforeignmemory_map(xc_interface *h, uint32_t dom,
- int prot, size_t pages,
- const xen_pfn_t arr[/*pages*/],
- int err[/*pages*/])
-{
- if (err)
- return xc_map_foreign_bulk(h, dom, prot, arr, err, pages);
- else
- return xc_map_foreign_pages(h, dom, prot, arr, pages);
-}
-
-#define xenforeignmemory_unmap(h, p, s) munmap(p, s * XC_PAGE_SIZE)
-
#else /* CONFIG_XEN_CTRL_INTERFACE_VERSION >= 40701 */
#include <xenforeignmemory.h>
diff --git a/softmmu/globals.c b/softmmu/globals.c
index 23bb27f0f6..dda32986f7 100644
--- a/softmmu/globals.c
+++ b/softmmu/globals.c
@@ -67,3 +67,4 @@ enum xen_mode xen_mode = XEN_DISABLED;
bool xen_domid_restrict;
struct evtchn_backend_ops *xen_evtchn_ops;
struct gnttab_backend_ops *xen_gnttab_ops;
+struct foreignmem_backend_ops *xen_foreignmem_ops;
--
2.35.3
next prev parent reply other threads:[~2023-01-10 13:10 UTC|newest]
Thread overview: 94+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-10 12:19 [PATCH v6 00/51] Xen support under KVM David Woodhouse
2023-01-10 12:19 ` [PATCH v6 01/51] include: import Xen public headers to include/standard-headers/ David Woodhouse
2023-01-10 12:19 ` [PATCH v6 02/51] xen: add CONFIG_XENFV_MACHINE and CONFIG_XEN_EMU options for Xen emulation David Woodhouse
2023-01-10 12:19 ` [PATCH v6 03/51] xen: Add XEN_DISABLED mode and make it default David Woodhouse
2023-01-10 12:19 ` [PATCH v6 04/51] i386/kvm: Add xen-version KVM accelerator property and init KVM Xen support David Woodhouse
2023-01-10 12:19 ` [PATCH v6 05/51] i386/kvm: handle Xen HVM cpuid leaves David Woodhouse
2023-01-10 12:19 ` [PATCH v6 06/51] i386/hvm: Set Xen vCPU ID in KVM David Woodhouse
2023-01-10 12:19 ` [PATCH v6 07/51] xen-platform: exclude vfio-pci from the PCI platform unplug David Woodhouse
2023-01-10 12:19 ` [PATCH v6 08/51] xen-platform: allow its creation with XEN_EMULATE mode David Woodhouse
2023-01-16 16:20 ` Paul Durrant
2023-01-16 17:56 ` David Woodhouse
2023-01-10 12:20 ` [PATCH v6 09/51] i386/xen: handle guest hypercalls David Woodhouse
2023-01-16 16:24 ` Paul Durrant
2023-01-16 17:57 ` David Woodhouse
2023-01-10 12:20 ` [PATCH v6 10/51] i386/xen: implement HYPERVISOR_xen_version David Woodhouse
2023-01-10 12:20 ` [PATCH v6 11/51] i386/xen: implement HYPERVISOR_sched_op, SCHEDOP_shutdown David Woodhouse
2023-01-16 16:27 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 12/51] i386/xen: Implement SCHEDOP_poll and SCHEDOP_yield David Woodhouse
2023-01-16 16:36 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 13/51] hw/xen: Add xen_overlay device for emulating shared xenheap pages David Woodhouse
2023-01-16 16:57 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 14/51] i386/xen: add pc_machine_kvm_type to initialize XEN_EMULATE mode David Woodhouse
2023-01-16 17:17 ` Paul Durrant
2023-01-16 19:45 ` David Woodhouse
2023-01-10 12:20 ` [PATCH v6 15/51] i386/xen: manage and save/restore Xen guest long_mode setting David Woodhouse
2023-01-16 17:20 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 16/51] i386/xen: implement HYPERVISOR_memory_op David Woodhouse
2023-01-16 17:28 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 17/51] i386/xen: implement XENMEM_add_to_physmap_batch David Woodhouse
2023-01-16 17:36 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 18/51] i386/xen: implement HYPERVISOR_hvm_op David Woodhouse
2023-01-16 17:39 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 19/51] i386/xen: implement HYPERVISOR_vcpu_op David Woodhouse
2023-01-16 17:40 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 20/51] i386/xen: handle VCPUOP_register_vcpu_info David Woodhouse
2023-01-16 17:46 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 21/51] i386/xen: handle VCPUOP_register_vcpu_time_info David Woodhouse
2023-01-16 17:53 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 22/51] i386/xen: handle VCPUOP_register_runstate_memory_area David Woodhouse
2023-01-16 17:56 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 23/51] i386/xen: implement HYPERVISOR_event_channel_op David Woodhouse
2023-01-16 17:59 ` Paul Durrant
2023-01-16 19:54 ` David Woodhouse
2023-01-10 12:20 ` [PATCH v6 24/51] i386/xen: implement HVMOP_set_evtchn_upcall_vector David Woodhouse
2023-01-10 12:20 ` [PATCH v6 25/51] i386/xen: implement HVMOP_set_param David Woodhouse
2023-01-16 18:00 ` Paul Durrant
2023-01-10 12:20 ` [PATCH v6 26/51] hw/xen: Add xen_evtchn device for event channel emulation David Woodhouse
2023-01-10 12:20 ` [PATCH v6 27/51] i386/xen: Add support for Xen event channel delivery to vCPU David Woodhouse
2023-01-10 12:20 ` [PATCH v6 28/51] hw/xen: Implement EVTCHNOP_status David Woodhouse
2023-01-10 12:20 ` [PATCH v6 29/51] hw/xen: Implement EVTCHNOP_close David Woodhouse
2023-01-10 12:20 ` [PATCH v6 30/51] hw/xen: Implement EVTCHNOP_unmask David Woodhouse
2023-01-10 12:20 ` [PATCH v6 31/51] hw/xen: Implement EVTCHNOP_bind_virq David Woodhouse
2023-01-10 12:20 ` [PATCH v6 32/51] hw/xen: Implement EVTCHNOP_bind_ipi David Woodhouse
2023-01-10 12:20 ` [PATCH v6 33/51] hw/xen: Implement EVTCHNOP_send David Woodhouse
2023-01-10 12:20 ` [PATCH v6 34/51] hw/xen: Implement EVTCHNOP_alloc_unbound David Woodhouse
2023-01-10 12:20 ` [PATCH v6 35/51] hw/xen: Implement EVTCHNOP_bind_interdomain David Woodhouse
2023-01-10 12:20 ` [PATCH v6 36/51] hw/xen: Implement EVTCHNOP_bind_vcpu David Woodhouse
2023-01-10 12:20 ` [PATCH v6 37/51] hw/xen: Implement EVTCHNOP_reset David Woodhouse
2023-01-10 12:20 ` [PATCH v6 38/51] i386/xen: add monitor commands to test event injection David Woodhouse
2023-01-11 14:28 ` Dr. David Alan Gilbert
2023-01-11 14:57 ` David Woodhouse
2023-01-10 12:20 ` [PATCH v6 39/51] hw/xen: Support HVM_PARAM_CALLBACK_TYPE_GSI callback David Woodhouse
2023-01-10 12:20 ` [PATCH v6 40/51] hw/xen: Support HVM_PARAM_CALLBACK_TYPE_PCI_INTX callback David Woodhouse
2023-01-10 12:20 ` [PATCH v6 41/51] kvm/i386: Add xen-gnttab-max-frames property David Woodhouse
2023-01-10 12:20 ` [PATCH v6 42/51] hw/xen: Add xen_gnttab device for grant table emulation David Woodhouse
2023-01-10 12:20 ` [PATCH v6 43/51] hw/xen: Support mapping grant frames David Woodhouse
2023-01-10 12:20 ` [PATCH v6 44/51] i386/xen: Implement HYPERVISOR_grant_table_op and GNTTABOP_[gs]et_verson David Woodhouse
2023-01-10 12:20 ` [PATCH v6 45/51] hw/xen: Implement GNTTABOP_query_size David Woodhouse
2023-01-10 12:20 ` [PATCH v6 46/51] i386/xen: handle PV timer hypercalls David Woodhouse
2023-01-10 12:20 ` [PATCH v6 47/51] i386/xen: Reserve Xen special pages for console, xenstore rings David Woodhouse
2023-01-10 12:20 ` [PATCH v6 48/51] i386/xen: handle HVMOP_get_param David Woodhouse
2023-01-10 12:20 ` [PATCH v6 49/51] hw/xen: Add backend implementation of interdomain event channel support David Woodhouse
2023-01-10 12:20 ` [PATCH v6 50/51] hw/xen: Add xen_xenstore device for xenstore emulation David Woodhouse
2023-01-10 12:20 ` [PATCH v6 51/51] hw/xen: Add basic ring handling to xenstore David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 00/15] Xen PV backend support for KVM/Xen guests David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 01/15] hw/xen: Add evtchn operations to allow redirection to internal emulation David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 02/15] hw/xen: Add emulated evtchn ops David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 03/15] hw/xen: Add gnttab operations to allow redirection to internal emulation David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 04/15] hw/xen: Pass grant ref to gnttab unmap David Woodhouse
2023-01-10 12:37 ` David Woodhouse [this message]
2023-01-10 12:37 ` [RFC PATCH v1 06/15] hw/xen: Add xenstore operations to allow redirection to internal emulation David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 07/15] hw/xen: Move xenstore_store_pv_console_info to xen_console.c David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 08/15] hw/xen: Use XEN_PAGE_SIZE in PV backend drivers David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 09/15] hw/xen: Rename xen_common.h to xen_native.h David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 10/15] hw/xen: Build PV backend drivers for XENFV_MACHINE David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 11/15] hw/xen: Map guest XENSTORE_PFN grant in emulated Xenstore David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 12/15] hw/xen: Add backend implementation of grant table operations David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 13/15] hw/xen: Implement soft reset for emulated gnttab David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 14/15] hw/xen: Remove old version of Xen headers David Woodhouse
2023-01-10 12:37 ` [RFC PATCH v1 15/15] i386/xen: Initialize XenBus and legacy backends from pc_init1() David Woodhouse
2023-01-10 15:43 ` [RFC PATCH v1 00/15] Xen PV backend support for KVM/Xen guests Joao Martins
2023-01-10 15:47 ` Joao Martins
2023-01-10 16:52 ` David Woodhouse
2023-01-10 17:26 ` Joao Martins
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