From: "Michael S. Tsirkin" <mst@redhat.com>
To: qemu-devel@nongnu.org
Cc: Peter Maydell <peter.maydell@linaro.org>,
Eduardo Habkost <ehabkost@redhat.com>,
qemu-block@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>,
Cornelia Huck <cornelia.huck@de.ibm.com>,
Paolo Bonzini <pbonzini@redhat.com>
Subject: [Qemu-devel] [PULL 08/49] virtio: introduce virtqueue_alloc_element
Date: Thu, 4 Feb 2016 23:51:28 +0200 [thread overview]
Message-ID: <1454612376-7072-9-git-send-email-mst@redhat.com> (raw)
In-Reply-To: <1454612376-7072-1-git-send-email-mst@redhat.com>
From: Paolo Bonzini <pbonzini@redhat.com>
Allocate the arrays for in_addr/out_addr/in_sg/out_sg outside the
VirtQueueElement. For now, virtqueue_pop and vring_pop keep
allocating a very large VirtQueueElement.
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
include/hw/virtio/virtio.h | 9 ++--
hw/virtio/dataplane/vring.c | 3 +-
hw/virtio/virtio.c | 110 +++++++++++++++++++++++++++++++++++++++-----
3 files changed, 105 insertions(+), 17 deletions(-)
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index 44da9a8..108cdb0 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -46,10 +46,10 @@ typedef struct VirtQueueElement
unsigned int index;
unsigned int out_num;
unsigned int in_num;
- hwaddr in_addr[VIRTQUEUE_MAX_SIZE];
- hwaddr out_addr[VIRTQUEUE_MAX_SIZE];
- struct iovec in_sg[VIRTQUEUE_MAX_SIZE];
- struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
+ hwaddr *in_addr;
+ hwaddr *out_addr;
+ struct iovec *in_sg;
+ struct iovec *out_sg;
} VirtQueueElement;
#define VIRTIO_QUEUE_MAX 1024
@@ -143,6 +143,7 @@ VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
void virtio_del_queue(VirtIODevice *vdev, int n);
+void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num);
void virtqueue_push(VirtQueue *vq, const VirtQueueElement *elem,
unsigned int len);
void virtqueue_flush(VirtQueue *vq, unsigned int count);
diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c
index 4fb84bb..57ada3b 100644
--- a/hw/virtio/dataplane/vring.c
+++ b/hw/virtio/dataplane/vring.c
@@ -403,8 +403,7 @@ void *vring_pop(VirtIODevice *vdev, Vring *vring, size_t sz)
goto out;
}
- assert(sz >= sizeof(VirtQueueElement));
- elem = g_malloc(sz);
+ elem = virtqueue_alloc_element(sz, VIRTQUEUE_MAX_SIZE, VIRTQUEUE_MAX_SIZE);
/* Initialize elem so it can be safely unmapped */
elem->in_num = elem->out_num = 0;
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 28fa7fe..661a1e1 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -494,11 +494,30 @@ static void virtqueue_map_iovec(struct iovec *sg, hwaddr *addr,
void virtqueue_map(VirtQueueElement *elem)
{
virtqueue_map_iovec(elem->in_sg, elem->in_addr, &elem->in_num,
- MIN(ARRAY_SIZE(elem->in_sg), ARRAY_SIZE(elem->in_addr)),
- 1);
+ VIRTQUEUE_MAX_SIZE, 1);
virtqueue_map_iovec(elem->out_sg, elem->out_addr, &elem->out_num,
- MIN(ARRAY_SIZE(elem->out_sg), ARRAY_SIZE(elem->out_addr)),
- 0);
+ VIRTQUEUE_MAX_SIZE, 0);
+}
+
+void *virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num)
+{
+ VirtQueueElement *elem;
+ size_t in_addr_ofs = QEMU_ALIGN_UP(sz, __alignof__(elem->in_addr[0]));
+ size_t out_addr_ofs = in_addr_ofs + in_num * sizeof(elem->in_addr[0]);
+ size_t out_addr_end = out_addr_ofs + out_num * sizeof(elem->out_addr[0]);
+ size_t in_sg_ofs = QEMU_ALIGN_UP(out_addr_end, __alignof__(elem->in_sg[0]));
+ size_t out_sg_ofs = in_sg_ofs + in_num * sizeof(elem->in_sg[0]);
+ size_t out_sg_end = out_sg_ofs + out_num * sizeof(elem->out_sg[0]);
+
+ assert(sz >= sizeof(VirtQueueElement));
+ elem = g_malloc(out_sg_end);
+ elem->out_num = out_num;
+ elem->in_num = in_num;
+ elem->in_addr = (void *)elem + in_addr_ofs;
+ elem->out_addr = (void *)elem + out_addr_ofs;
+ elem->in_sg = (void *)elem + in_sg_ofs;
+ elem->out_sg = (void *)elem + out_sg_ofs;
+ return elem;
}
void *virtqueue_pop(VirtQueue *vq, size_t sz)
@@ -513,8 +532,7 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
}
/* When we start there are none of either input nor output. */
- assert(sz >= sizeof(VirtQueueElement));
- elem = g_malloc(sz);
+ elem = virtqueue_alloc_element(sz, VIRTQUEUE_MAX_SIZE, VIRTQUEUE_MAX_SIZE);
elem->out_num = elem->in_num = 0;
max = vq->vring.num;
@@ -541,14 +559,14 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
struct iovec *sg;
if (vring_desc_flags(vdev, desc_pa, i) & VRING_DESC_F_WRITE) {
- if (elem->in_num >= ARRAY_SIZE(elem->in_sg)) {
+ if (elem->in_num >= VIRTQUEUE_MAX_SIZE) {
error_report("Too many write descriptors in indirect table");
exit(1);
}
elem->in_addr[elem->in_num] = vring_desc_addr(vdev, desc_pa, i);
sg = &elem->in_sg[elem->in_num++];
} else {
- if (elem->out_num >= ARRAY_SIZE(elem->out_sg)) {
+ if (elem->out_num >= VIRTQUEUE_MAX_SIZE) {
error_report("Too many read descriptors in indirect table");
exit(1);
}
@@ -576,17 +594,87 @@ void *virtqueue_pop(VirtQueue *vq, size_t sz)
return elem;
}
+/* Reading and writing a structure directly to QEMUFile is *awful*, but
+ * it is what QEMU has always done by mistake. We can change it sooner
+ * or later by bumping the version number of the affected vm states.
+ * In the meanwhile, since the in-memory layout of VirtQueueElement
+ * has changed, we need to marshal to and from the layout that was
+ * used before the change.
+ */
+typedef struct VirtQueueElementOld {
+ unsigned int index;
+ unsigned int out_num;
+ unsigned int in_num;
+ hwaddr in_addr[VIRTQUEUE_MAX_SIZE];
+ hwaddr out_addr[VIRTQUEUE_MAX_SIZE];
+ struct iovec in_sg[VIRTQUEUE_MAX_SIZE];
+ struct iovec out_sg[VIRTQUEUE_MAX_SIZE];
+} VirtQueueElementOld;
+
void *qemu_get_virtqueue_element(QEMUFile *f, size_t sz)
{
- VirtQueueElement *elem = g_malloc(sz);
- qemu_get_buffer(f, (uint8_t *)elem, sizeof(VirtQueueElement));
+ VirtQueueElement *elem;
+ VirtQueueElementOld data;
+ int i;
+
+ qemu_get_buffer(f, (uint8_t *)&data, sizeof(VirtQueueElementOld));
+
+ elem = virtqueue_alloc_element(sz, data.out_num, data.in_num);
+ elem->index = data.index;
+
+ for (i = 0; i < elem->in_num; i++) {
+ elem->in_addr[i] = data.in_addr[i];
+ }
+
+ for (i = 0; i < elem->out_num; i++) {
+ elem->out_addr[i] = data.out_addr[i];
+ }
+
+ for (i = 0; i < elem->in_num; i++) {
+ /* Base is overwritten by virtqueue_map. */
+ elem->in_sg[i].iov_base = 0;
+ elem->in_sg[i].iov_len = data.in_sg[i].iov_len;
+ }
+
+ for (i = 0; i < elem->out_num; i++) {
+ /* Base is overwritten by virtqueue_map. */
+ elem->out_sg[i].iov_base = 0;
+ elem->out_sg[i].iov_len = data.out_sg[i].iov_len;
+ }
+
virtqueue_map(elem);
return elem;
}
void qemu_put_virtqueue_element(QEMUFile *f, VirtQueueElement *elem)
{
- qemu_put_buffer(f, (uint8_t *)elem, sizeof(VirtQueueElement));
+ VirtQueueElementOld data;
+ int i;
+
+ memset(&data, 0, sizeof(data));
+ data.index = elem->index;
+ data.in_num = elem->in_num;
+ data.out_num = elem->out_num;
+
+ for (i = 0; i < elem->in_num; i++) {
+ data.in_addr[i] = elem->in_addr[i];
+ }
+
+ for (i = 0; i < elem->out_num; i++) {
+ data.out_addr[i] = elem->out_addr[i];
+ }
+
+ for (i = 0; i < elem->in_num; i++) {
+ /* Base is overwritten by virtqueue_map when loading. Do not
+ * save it, as it would leak the QEMU address space layout. */
+ data.in_sg[i].iov_len = elem->in_sg[i].iov_len;
+ }
+
+ for (i = 0; i < elem->out_num; i++) {
+ /* Do not save iov_base as above. */
+ data.out_sg[i].iov_len = elem->out_sg[i].iov_len;
+ }
+ qemu_put_buffer(f, (uint8_t *)&data, sizeof(VirtQueueElementOld));
}
/* virtio device */
--
MST
next prev parent reply other threads:[~2016-02-04 21:51 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-02-04 21:50 [Qemu-devel] [PULL 00/49] pc and misc cleanups and fixes, virtio optimizations Michael S. Tsirkin
2016-02-04 21:50 ` [Qemu-devel] [PULL 14/49] virtio: combine write of an entry into used ring Michael S. Tsirkin
2016-02-04 21:50 ` [Qemu-devel] [PULL 01/49] Fix virtio migration Michael S. Tsirkin
2016-02-04 21:50 ` [Qemu-devel] [PULL 02/49] pc: acpi: merge SSDT into DSDT Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 03/49] tests: pc: acpi: drop not needed 'expected SSDT' blobs Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 04/49] tests: pc: acpi: add expected DSDT.bridge blobs and update DSDT blobs Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 05/49] virtio: move VirtQueueElement at the beginning of the structs Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 06/49] virtio: move allocation to virtqueue_pop/vring_pop Michael S. Tsirkin
2016-02-05 12:52 ` Peter Maydell
2016-02-06 18:10 ` Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 07/49] virtio: introduce qemu_get/put_virtqueue_element Michael S. Tsirkin
2016-02-04 21:51 ` Michael S. Tsirkin [this message]
2016-02-04 21:51 ` [Qemu-devel] [PULL 09/49] virtio: slim down allocation of VirtQueueElements Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 10/49] vring: " Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 11/49] virtio: combine the read of a descriptor Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 12/49] virtio: cache used_idx in a VirtQueue field Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 13/49] virtio: read avail_idx from VQ only when necessary Michael S. Tsirkin
2016-02-04 21:51 ` [Qemu-devel] [PULL 15/49] hw/pxb: add pxb devices to the bridge category Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 16/49] vhost-user-test: use correct ROM to speed up and avoid spurious failures Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 17/49] hw/pci: ensure that only PCI/PCIe bridges can be attached to pxb/pxb-pcie devices Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 18/49] ipmi: replace goto by a return statement Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 19/49] ipmi: replace *_MAXCMD defines Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 20/49] ipmi: cleanup error_report messages Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 21/49] ipmi: fix SDR length value Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 22/49] ipmi: introduce a struct ipmi_sdr_compact Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 23/49] ipmi: add get and set SENSOR_TYPE commands Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 24/49] ipmi: add GET_SYS_RESTART_CAUSE chassis command Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 25/49] ipmi: add ACPI power and GUID commands Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 26/49] pc: Move PcGuestInfo declaration to top of file Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 27/49] pc: Eliminate struct PcGuestInfoState Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 28/49] pc: Simplify pc_memory_init() signature Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 29/49] pc: Simplify xen_load_linux() signature Michael S. Tsirkin
2016-02-04 21:52 ` [Qemu-devel] [PULL 30/49] acpi: Remove guest_info parameters from functions Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 31/49] acpi: Don't save PcGuestInfo on AcpiBuildState Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 32/49] pc: Remove compat fields from PcGuestInfo Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 33/49] pc: Remove RAM size " Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 34/49] pc: Remove PcGuestInfo.isapc_ram_fw field Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 35/49] pc: Move PcGuestInfo.fw_cfg to PCMachineState Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 36/49] pc: Move APIC and NUMA data from PcGuestInfo " Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 37/49] pc: Eliminate PcGuestInfo struct Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 38/49] acpi: take oem_id in build_header(), optionally Michael S. Tsirkin
2016-02-04 22:25 ` Laszlo Ersek
2016-02-04 21:53 ` [Qemu-devel] [PULL 39/49] acpi: expose oem_id and oem_table_id in build_rsdt() Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 40/49] acpi: add function to extract oem_id and oem_table_id from the user's SLIC Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 41/49] pc: set the OEM fields in the RSDT and the FADT from the SLIC Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 42/49] dimm: Correct type of MemoryHotplugState->base Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 43/49] intel_iommu: large page support Michael S. Tsirkin
2016-02-04 21:53 ` [Qemu-devel] [PULL 44/49] fix MSI injection on Xen Michael S. Tsirkin
2016-02-04 21:54 ` [Qemu-devel] [PULL 45/49] net: set endianness on all backend devices Michael S. Tsirkin
2016-02-05 8:54 ` Greg Kurz
2016-02-04 21:54 ` [Qemu-devel] [PULL 46/49] i386/acpi: make floppy controller object dynamic Michael S. Tsirkin
2016-02-04 21:54 ` [Qemu-devel] [PULL 47/49] expose floppy drive geometry and CMOS type Michael S. Tsirkin
2016-02-04 21:54 ` [Qemu-devel] [PULL 48/49] i386: populate floppy drive information in DSDT Michael S. Tsirkin
2016-02-05 18:25 ` Igor Mammedov
2016-02-08 13:14 ` Roman Kagan
2016-02-08 20:20 ` John Snow
2016-02-09 15:52 ` Roman Kagan
2016-02-09 16:22 ` John Snow
2016-02-09 18:36 ` Laszlo Ersek
2016-02-09 18:48 ` Michael S. Tsirkin
2016-02-10 16:14 ` John Snow
2016-02-10 16:48 ` Michael S. Tsirkin
2016-02-10 17:24 ` Roman Kagan
2016-02-10 17:10 ` Roman Kagan
2016-02-10 17:16 ` John Snow
2016-02-10 17:33 ` Roman Kagan
2016-02-10 21:54 ` John Snow
2016-02-13 17:26 ` Kevin O'Connor
2016-02-14 6:45 ` Laszlo Ersek
2016-02-14 15:02 ` Michael S. Tsirkin
2016-02-17 14:31 ` Roman Kagan
2016-02-10 16:57 ` Roman Kagan
2016-02-04 21:54 ` [Qemu-devel] [PULL 49/49] acpi: update expected DSDT Michael S. Tsirkin
2016-02-05 15:03 ` [Qemu-devel] [PULL 00/49] pc and misc cleanups and fixes, virtio optimizations Peter Maydell
2016-02-05 18:19 ` Igor Mammedov
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1454612376-7072-9-git-send-email-mst@redhat.com \
--to=mst@redhat.com \
--cc=cornelia.huck@de.ibm.com \
--cc=ehabkost@redhat.com \
--cc=pbonzini@redhat.com \
--cc=peter.maydell@linaro.org \
--cc=qemu-block@nongnu.org \
--cc=qemu-devel@nongnu.org \
--cc=stefanha@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).