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Pull request 

v3:
  * Fix linker error on FreeBSD and other !CONFIG_LINUX host OSes [Peter]
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Merge remote-tracking branch 'remotes/stefanha-gitlab/tags/block-pull-request' into staging

Pull request

v3:
 * Fix linker error on FreeBSD and other !CONFIG_LINUX host OSes [Peter]

# gpg: Signature made Fri 23 Oct 2020 16:21:19 BST
# gpg:                using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha-gitlab/tags/block-pull-request: (28 commits)
  iotests: add commit top->base cases to 274
  block/io: fix bdrv_is_allocated_above
  block/io: bdrv_common_block_status_above: support bs == base
  block/io: bdrv_common_block_status_above: support include_base
  block/io: fix bdrv_co_block_status_above
  block/export: add vhost-user-blk multi-queue support
  block/export: add iothread and fixed-iothread options
  block: move block exports to libblockdev
  qemu-storage-daemon: avoid compiling blockdev_ss twice
  util/vhost-user-server: use static library in meson.build
  util/vhost-user-server: move header to include/
  block/export: convert vhost-user-blk server to block export API
  block/export: report flush errors
  util/vhost-user-server: rework vu_client_trip() coroutine lifecycle
  util/vhost-user-server: check EOF when reading payload
  util/vhost-user-server: fix memory leak in vu_message_read()
  util/vhost-user-server: drop unused DevicePanicNotifier
  block/export: consolidate request structs into VuBlockReq
  util/vhost-user-server: drop unnecessary watch deletion
  util/vhost-user-server: drop unnecessary QOM cast
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Peter Maydell 2020-10-26 10:33:59 +00:00
parent 4c5b97bfd0 4f193168af
commit a5fac424c7
33 changed files with 1421 additions and 123 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
MAINTAINERS
View File

@ -3069,6 +3069,15 @@ L: qemu-block@nongnu.org
S: Supported
F: tests/image-fuzzer/
Vhost-user block device backend server
M: Coiby Xu <Coiby.Xu@gmail.com>
S: Maintained
F: block/export/vhost-user-blk-server.c
F: block/export/vhost-user-blk-server.h
F: include/qemu/vhost-user-server.h
F: tests/qtest/libqos/vhost-user-blk.c
F: util/vhost-user-server.c
Replication
M: Wen Congyang <wencongyang2@huawei.com>
M: Xie Changlong <xiechanglong.d@gmail.com>

2
block/coroutines.h
View File

@ -41,6 +41,7 @@ bdrv_pwritev(BdrvChild *child, int64_t offset, unsigned int bytes,
int coroutine_fn
bdrv_co_common_block_status_above(BlockDriverState *bs,
BlockDriverState *base,
bool include_base,
bool want_zero,
int64_t offset,
int64_t bytes,
@ -50,6 +51,7 @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
int generated_co_wrapper
bdrv_common_block_status_above(BlockDriverState *bs,
BlockDriverState *base,
bool include_base,
bool want_zero,
int64_t offset,
int64_t bytes,

37
block/export/export.c
View File

@ -15,15 +15,22 @@
#include "block/block.h"
#include "sysemu/block-backend.h"
#include "sysemu/iothread.h"
#include "block/export.h"
#include "block/nbd.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-block-export.h"
#include "qapi/qapi-events-block-export.h"
#include "qemu/id.h"
#if defined(CONFIG_LINUX) && defined(CONFIG_VHOST_USER)
#include "vhost-user-blk-server.h"
#endif
static const BlockExportDriver *blk_exp_drivers[] = {
&blk_exp_nbd,
#if defined(CONFIG_LINUX) && defined(CONFIG_VHOST_USER)
&blk_exp_vhost_user_blk,
#endif
};
/* Only accessed from the main thread */
@ -57,10 +64,11 @@ static const BlockExportDriver *blk_exp_find_driver(BlockExportType type)
BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
{
bool fixed_iothread = export->has_fixed_iothread && export->fixed_iothread;
const BlockExportDriver *drv;
BlockExport *exp = NULL;
BlockDriverState *bs;
BlockBackend *blk;
BlockBackend *blk = NULL;
AioContext *ctx;
uint64_t perm;
int ret;
@ -96,6 +104,28 @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
ctx = bdrv_get_aio_context(bs);
aio_context_acquire(ctx);
if (export->has_iothread) {
IOThread *iothread;
AioContext *new_ctx;
iothread = iothread_by_id(export->iothread);
if (!iothread) {
error_setg(errp, "iothread \"%s\" not found", export->iothread);
goto fail;
}
new_ctx = iothread_get_aio_context(iothread);
ret = bdrv_try_set_aio_context(bs, new_ctx, errp);
if (ret == 0) {
aio_context_release(ctx);
aio_context_acquire(new_ctx);
ctx = new_ctx;
} else if (fixed_iothread) {
goto fail;
}
}
/*
* Block exports are used for non-shared storage migration. Make sure
* that BDRV_O_INACTIVE is cleared and the image is ready for write
@ -110,6 +140,11 @@ BlockExport *blk_exp_add(BlockExportOptions *export, Error **errp)
}
blk = blk_new(ctx, perm, BLK_PERM_ALL);
if (!fixed_iothread) {
blk_set_allow_aio_context_change(blk, true);
}
ret = blk_insert_bs(blk, bs, errp);
if (ret < 0) {
goto fail;

3
block/export/meson.build
View File

@ -1 +1,2 @@
block_ss.add(files('export.c'))
blockdev_ss.add(files('export.c'))
blockdev_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: files('vhost-user-blk-server.c'))

431
block/export/vhost-user-blk-server.c Normal file
View File

@ -0,0 +1,431 @@
/*
* Sharing QEMU block devices via vhost-user protocal
*
* Parts of the code based on nbd/server.c.
*
* Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
* Copyright (c) 2020 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "block/block.h"
#include "contrib/libvhost-user/libvhost-user.h"
#include "standard-headers/linux/virtio_blk.h"
#include "qemu/vhost-user-server.h"
#include "vhost-user-blk-server.h"
#include "qapi/error.h"
#include "qom/object_interfaces.h"
#include "sysemu/block-backend.h"
#include "util/block-helpers.h"
enum {
VHOST_USER_BLK_NUM_QUEUES_DEFAULT = 1,
};
struct virtio_blk_inhdr {
unsigned char status;
};
typedef struct VuBlkReq {
VuVirtqElement elem;
int64_t sector_num;
size_t size;
struct virtio_blk_inhdr *in;
struct virtio_blk_outhdr out;
VuServer *server;
struct VuVirtq *vq;
} VuBlkReq;
/* vhost user block device */
typedef struct {
BlockExport export;
VuServer vu_server;
uint32_t blk_size;
QIOChannelSocket *sioc;
struct virtio_blk_config blkcfg;
bool writable;
} VuBlkExport;
static void vu_blk_req_complete(VuBlkReq *req)
{
VuDev *vu_dev = &req->server->vu_dev;
/* IO size with 1 extra status byte */
vu_queue_push(vu_dev, req->vq, &req->elem, req->size + 1);
vu_queue_notify(vu_dev, req->vq);
free(req);
}
static int coroutine_fn
vu_blk_discard_write_zeroes(BlockBackend *blk, struct iovec *iov,
uint32_t iovcnt, uint32_t type)
{
struct virtio_blk_discard_write_zeroes desc;
ssize_t size = iov_to_buf(iov, iovcnt, 0, &desc, sizeof(desc));
if (unlikely(size != sizeof(desc))) {
error_report("Invalid size %zd, expect %zu", size, sizeof(desc));
return -EINVAL;
}
uint64_t range[2] = { le64_to_cpu(desc.sector) << 9,
le32_to_cpu(desc.num_sectors) << 9 };
if (type == VIRTIO_BLK_T_DISCARD) {
if (blk_co_pdiscard(blk, range[0], range[1]) == 0) {
return 0;
}
} else if (type == VIRTIO_BLK_T_WRITE_ZEROES) {
if (blk_co_pwrite_zeroes(blk, range[0], range[1], 0) == 0) {
return 0;
}
}
return -EINVAL;
}
static void coroutine_fn vu_blk_virtio_process_req(void *opaque)
{
VuBlkReq *req = opaque;
VuServer *server = req->server;
VuVirtqElement *elem = &req->elem;
uint32_t type;
VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
BlockBackend *blk = vexp->export.blk;
struct iovec *in_iov = elem->in_sg;
struct iovec *out_iov = elem->out_sg;
unsigned in_num = elem->in_num;
unsigned out_num = elem->out_num;
/* refer to hw/block/virtio_blk.c */
if (elem->out_num < 1 || elem->in_num < 1) {
error_report("virtio-blk request missing headers");
goto err;
}
if (unlikely(iov_to_buf(out_iov, out_num, 0, &req->out,
sizeof(req->out)) != sizeof(req->out))) {
error_report("virtio-blk request outhdr too short");
goto err;
}
iov_discard_front(&out_iov, &out_num, sizeof(req->out));
if (in_iov[in_num - 1].iov_len < sizeof(struct virtio_blk_inhdr)) {
error_report("virtio-blk request inhdr too short");
goto err;
}
/* We always touch the last byte, so just see how big in_iov is. */
req->in = (void *)in_iov[in_num - 1].iov_base
+ in_iov[in_num - 1].iov_len
- sizeof(struct virtio_blk_inhdr);
iov_discard_back(in_iov, &in_num, sizeof(struct virtio_blk_inhdr));
type = le32_to_cpu(req->out.type);
switch (type & ~VIRTIO_BLK_T_BARRIER) {
case VIRTIO_BLK_T_IN:
case VIRTIO_BLK_T_OUT: {
ssize_t ret = 0;
bool is_write = type & VIRTIO_BLK_T_OUT;
req->sector_num = le64_to_cpu(req->out.sector);
if (is_write && !vexp->writable) {
req->in->status = VIRTIO_BLK_S_IOERR;
break;
}
int64_t offset = req->sector_num * vexp->blk_size;
QEMUIOVector qiov;
if (is_write) {
qemu_iovec_init_external(&qiov, out_iov, out_num);
ret = blk_co_pwritev(blk, offset, qiov.size, &qiov, 0);
} else {
qemu_iovec_init_external(&qiov, in_iov, in_num);
ret = blk_co_preadv(blk, offset, qiov.size, &qiov, 0);
}
if (ret >= 0) {
req->in->status = VIRTIO_BLK_S_OK;
} else {
req->in->status = VIRTIO_BLK_S_IOERR;
}
break;
}
case VIRTIO_BLK_T_FLUSH:
if (blk_co_flush(blk) == 0) {
req->in->status = VIRTIO_BLK_S_OK;
} else {
req->in->status = VIRTIO_BLK_S_IOERR;
}
break;
case VIRTIO_BLK_T_GET_ID: {
size_t size = MIN(iov_size(&elem->in_sg[0], in_num),
VIRTIO_BLK_ID_BYTES);
snprintf(elem->in_sg[0].iov_base, size, "%s", "vhost_user_blk");
req->in->status = VIRTIO_BLK_S_OK;
req->size = elem->in_sg[0].iov_len;
break;
}
case VIRTIO_BLK_T_DISCARD:
case VIRTIO_BLK_T_WRITE_ZEROES: {
int rc;
if (!vexp->writable) {
req->in->status = VIRTIO_BLK_S_IOERR;
break;
}
rc = vu_blk_discard_write_zeroes(blk, &elem->out_sg[1], out_num, type);
if (rc == 0) {
req->in->status = VIRTIO_BLK_S_OK;
} else {
req->in->status = VIRTIO_BLK_S_IOERR;
}
break;
}
default:
req->in->status = VIRTIO_BLK_S_UNSUPP;
break;
}
vu_blk_req_complete(req);
return;
err:
free(req);
}
static void vu_blk_process_vq(VuDev *vu_dev, int idx)
{
VuServer *server = container_of(vu_dev, VuServer, vu_dev);
VuVirtq *vq = vu_get_queue(vu_dev, idx);
while (1) {
VuBlkReq *req;
req = vu_queue_pop(vu_dev, vq, sizeof(VuBlkReq));
if (!req) {
break;
}
req->server = server;
req->vq = vq;
Coroutine *co =
qemu_coroutine_create(vu_blk_virtio_process_req, req);
qemu_coroutine_enter(co);
}
}
static void vu_blk_queue_set_started(VuDev *vu_dev, int idx, bool started)
{
VuVirtq *vq;
assert(vu_dev);
vq = vu_get_queue(vu_dev, idx);
vu_set_queue_handler(vu_dev, vq, started ? vu_blk_process_vq : NULL);
}
static uint64_t vu_blk_get_features(VuDev *dev)
{
uint64_t features;
VuServer *server = container_of(dev, VuServer, vu_dev);
VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
features = 1ull << VIRTIO_BLK_F_SIZE_MAX |
1ull << VIRTIO_BLK_F_SEG_MAX |
1ull << VIRTIO_BLK_F_TOPOLOGY |
1ull << VIRTIO_BLK_F_BLK_SIZE |
1ull << VIRTIO_BLK_F_FLUSH |
1ull << VIRTIO_BLK_F_DISCARD |
1ull << VIRTIO_BLK_F_WRITE_ZEROES |
1ull << VIRTIO_BLK_F_CONFIG_WCE |
1ull << VIRTIO_BLK_F_MQ |
1ull << VIRTIO_F_VERSION_1 |
1ull << VIRTIO_RING_F_INDIRECT_DESC |
1ull << VIRTIO_RING_F_EVENT_IDX |
1ull << VHOST_USER_F_PROTOCOL_FEATURES;
if (!vexp->writable) {
features |= 1ull << VIRTIO_BLK_F_RO;
}
return features;
}
static uint64_t vu_blk_get_protocol_features(VuDev *dev)
{
return 1ull << VHOST_USER_PROTOCOL_F_CONFIG |
1ull << VHOST_USER_PROTOCOL_F_INFLIGHT_SHMFD;
}
static int
vu_blk_get_config(VuDev *vu_dev, uint8_t *config, uint32_t len)
{
/* TODO blkcfg must be little-endian for VIRTIO 1.0 */
VuServer *server = container_of(vu_dev, VuServer, vu_dev);
VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
memcpy(config, &vexp->blkcfg, len);
return 0;
}
static int
vu_blk_set_config(VuDev *vu_dev, const uint8_t *data,
uint32_t offset, uint32_t size, uint32_t flags)
{
VuServer *server = container_of(vu_dev, VuServer, vu_dev);
VuBlkExport *vexp = container_of(server, VuBlkExport, vu_server);
uint8_t wce;
/* don't support live migration */
if (flags != VHOST_SET_CONFIG_TYPE_MASTER) {
return -EINVAL;
}
if (offset != offsetof(struct virtio_blk_config, wce) ||
size != 1) {
return -EINVAL;
}
wce = *data;
vexp->blkcfg.wce = wce;
blk_set_enable_write_cache(vexp->export.blk, wce);
return 0;
}
/*
* When the client disconnects, it sends a VHOST_USER_NONE request
* and vu_process_message will simple call exit which cause the VM
* to exit abruptly.
* To avoid this issue, process VHOST_USER_NONE request ahead
* of vu_process_message.
*
*/
static int vu_blk_process_msg(VuDev *dev, VhostUserMsg *vmsg, int *do_reply)
{
if (vmsg->request == VHOST_USER_NONE) {
dev->panic(dev, "disconnect");
return true;
}
return false;
}
static const VuDevIface vu_blk_iface = {
.get_features = vu_blk_get_features,
.queue_set_started = vu_blk_queue_set_started,
.get_protocol_features = vu_blk_get_protocol_features,
.get_config = vu_blk_get_config,
.set_config = vu_blk_set_config,
.process_msg = vu_blk_process_msg,
};
static void blk_aio_attached(AioContext *ctx, void *opaque)
{
VuBlkExport *vexp = opaque;
vexp->export.ctx = ctx;
vhost_user_server_attach_aio_context(&vexp->vu_server, ctx);
}
static void blk_aio_detach(void *opaque)
{
VuBlkExport *vexp = opaque;
vhost_user_server_detach_aio_context(&vexp->vu_server);
vexp->export.ctx = NULL;
}
static void
vu_blk_initialize_config(BlockDriverState *bs,
struct virtio_blk_config *config,
uint32_t blk_size,
uint16_t num_queues)
{
config->capacity = bdrv_getlength(bs) >> BDRV_SECTOR_BITS;
config->blk_size = blk_size;
config->size_max = 0;
config->seg_max = 128 - 2;
config->min_io_size = 1;
config->opt_io_size = 1;
config->num_queues = num_queues;
config->max_discard_sectors = 32768;
config->max_discard_seg = 1;
config->discard_sector_alignment = config->blk_size >> 9;
config->max_write_zeroes_sectors = 32768;
config->max_write_zeroes_seg = 1;
}
static void vu_blk_exp_request_shutdown(BlockExport *exp)
{
VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
vhost_user_server_stop(&vexp->vu_server);
}
static int vu_blk_exp_create(BlockExport *exp, BlockExportOptions *opts,
Error **errp)
{
VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
BlockExportOptionsVhostUserBlk *vu_opts = &opts->u.vhost_user_blk;
Error *local_err = NULL;
uint64_t logical_block_size;
uint16_t num_queues = VHOST_USER_BLK_NUM_QUEUES_DEFAULT;
vexp->writable = opts->writable;
vexp->blkcfg.wce = 0;
if (vu_opts->has_logical_block_size) {
logical_block_size = vu_opts->logical_block_size;
} else {
logical_block_size = BDRV_SECTOR_SIZE;
}
check_block_size(exp->id, "logical-block-size", logical_block_size,
&local_err);
if (local_err) {
error_propagate(errp, local_err);
return -EINVAL;
}
vexp->blk_size = logical_block_size;
blk_set_guest_block_size(exp->blk, logical_block_size);
if (vu_opts->has_num_queues) {
num_queues = vu_opts->num_queues;
}
if (num_queues == 0) {
error_setg(errp, "num-queues must be greater than 0");
return -EINVAL;
}
vu_blk_initialize_config(blk_bs(exp->blk), &vexp->blkcfg,
logical_block_size, num_queues);
blk_add_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
vexp);
if (!vhost_user_server_start(&vexp->vu_server, vu_opts->addr, exp->ctx,
num_queues, &vu_blk_iface, errp)) {
blk_remove_aio_context_notifier(exp->blk, blk_aio_attached,
blk_aio_detach, vexp);
return -EADDRNOTAVAIL;
}
return 0;
}
static void vu_blk_exp_delete(BlockExport *exp)
{
VuBlkExport *vexp = container_of(exp, VuBlkExport, export);
blk_remove_aio_context_notifier(exp->blk, blk_aio_attached, blk_aio_detach,
vexp);
}
const BlockExportDriver blk_exp_vhost_user_blk = {
.type = BLOCK_EXPORT_TYPE_VHOST_USER_BLK,
.instance_size = sizeof(VuBlkExport),
.create = vu_blk_exp_create,
.delete = vu_blk_exp_delete,
.request_shutdown = vu_blk_exp_request_shutdown,
};

19
block/export/vhost-user-blk-server.h Normal file
View File

@ -0,0 +1,19 @@
/*
* Sharing QEMU block devices via vhost-user protocal
*
* Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
* Copyright (c) 2020 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*/
#ifndef VHOST_USER_BLK_SERVER_H
#define VHOST_USER_BLK_SERVER_H
#include "block/export.h"
/* For block/export/export.c */
extern const BlockExportDriver blk_exp_vhost_user_blk;
#endif /* VHOST_USER_BLK_SERVER_H */

134
block/io.c
View File

@ -2343,6 +2343,7 @@ early_out:
int coroutine_fn
bdrv_co_common_block_status_above(BlockDriverState *bs,
BlockDriverState *base,
bool include_base,
bool want_zero,
int64_t offset,
int64_t bytes,
@ -2350,34 +2351,84 @@ bdrv_co_common_block_status_above(BlockDriverState *bs,
int64_t *map,
BlockDriverState **file)
{
int ret;
BlockDriverState *p;
int ret = 0;
bool first = true;
int64_t eof = 0;
assert(bs != base);
for (p = bs; p != base; p = bdrv_filter_or_cow_bs(p)) {
assert(!include_base || base); /* Can't include NULL base */
if (!include_base && bs == base) {
*pnum = bytes;
return 0;
}
ret = bdrv_co_block_status(bs, want_zero, offset, bytes, pnum, map, file);
if (ret < 0 || *pnum == 0 || ret & BDRV_BLOCK_ALLOCATED || bs == base) {
return ret;
}
if (ret & BDRV_BLOCK_EOF) {
eof = offset + *pnum;
}
assert(*pnum <= bytes);
bytes = *pnum;
for (p = bdrv_filter_or_cow_bs(bs); include_base || p != base;
p = bdrv_filter_or_cow_bs(p))
{
ret = bdrv_co_block_status(p, want_zero, offset, bytes, pnum, map,
file);
if (ret < 0) {
break;
return ret;
}
if (ret & BDRV_BLOCK_ZERO && ret & BDRV_BLOCK_EOF && !first) {
if (*pnum == 0) {
/*
* Reading beyond the end of the file continues to read
* zeroes, but we can only widen the result to the
* unallocated length we learned from an earlier
* iteration.
* The top layer deferred to this layer, and because this layer is
* short, any zeroes that we synthesize beyond EOF behave as if they
* were allocated at this layer.
*
* We don't include BDRV_BLOCK_EOF into ret, as upper layer may be
* larger. We'll add BDRV_BLOCK_EOF if needed at function end, see
* below.
*/
assert(ret & BDRV_BLOCK_EOF);
*pnum = bytes;
}
if (ret & (BDRV_BLOCK_ZERO | BDRV_BLOCK_DATA)) {
if (file) {
*file = p;
}
ret = BDRV_BLOCK_ZERO | BDRV_BLOCK_ALLOCATED;
break;
}
/* [offset, pnum] unallocated on this layer, which could be only
* the first part of [offset, bytes]. */
bytes = MIN(bytes, *pnum);
first = false;
if (ret & BDRV_BLOCK_ALLOCATED) {
/*
* We've found the node and the status, we must break.
*
* Drop BDRV_BLOCK_EOF, as it's not for upper layer, which may be
* larger. We'll add BDRV_BLOCK_EOF if needed at function end, see
* below.
*/
ret &= ~BDRV_BLOCK_EOF;
break;
}
if (p == base) {
assert(include_base);
break;
}
/*
* OK, [offset, offset + *pnum) region is unallocated on this layer,
* let's continue the diving.
*/
assert(*pnum <= bytes);
bytes = *pnum;
}
if (offset + *pnum == eof) {
ret |= BDRV_BLOCK_EOF;
}
return ret;
}
@ -2385,7 +2436,7 @@ int bdrv_block_status_above(BlockDriverState *bs, BlockDriverState *base,
int64_t offset, int64_t bytes, int64_t *pnum,
int64_t *map, BlockDriverState **file)
{
return bdrv_common_block_status_above(bs, base, true, offset, bytes,
return bdrv_common_block_status_above(bs, base, false, true, offset, bytes,
pnum, map, file);
}
@ -2402,9 +2453,9 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset,
int ret;
int64_t dummy;
ret = bdrv_common_block_status_above(bs, bdrv_filter_or_cow_bs(bs), false,
offset, bytes, pnum ? pnum : &dummy,
NULL, NULL);
ret = bdrv_common_block_status_above(bs, bs, true, false, offset,
bytes, pnum ? pnum : &dummy, NULL,
NULL);
if (ret < 0) {
return ret;
}
@ -2426,52 +2477,19 @@ int coroutine_fn bdrv_is_allocated(BlockDriverState *bs, int64_t offset,
* at 'offset + *pnum' may return the same allocation status (in other
* words, the result is not necessarily the maximum possible range);
* but 'pnum' will only be 0 when end of file is reached.
*
*/
int bdrv_is_allocated_above(BlockDriverState *top,
BlockDriverState *base,
bool include_base, int64_t offset,
int64_t bytes, int64_t *pnum)
{
BlockDriverState *intermediate;
int ret;
int64_t n = bytes;
assert(base || !include_base);
intermediate = top;
while (include_base || intermediate != base) {
int64_t pnum_inter;
int64_t size_inter;
assert(intermediate);
ret = bdrv_is_allocated(intermediate, offset, bytes, &pnum_inter);
if (ret < 0) {
return ret;
}
if (ret) {
*pnum = pnum_inter;
return 1;
}
size_inter = bdrv_getlength(intermediate);
if (size_inter < 0) {
return size_inter;
}
if (n > pnum_inter &&
(intermediate == top || offset + pnum_inter < size_inter)) {
n = pnum_inter;
}
if (intermediate == base) {
break;
}
intermediate = bdrv_filter_or_cow_bs(intermediate);
int ret = bdrv_common_block_status_above(top, base, include_base, false,
offset, bytes, pnum, NULL, NULL);
if (ret < 0) {
return ret;
}
*pnum = n;
return 0;
return !!(ret & BDRV_BLOCK_ALLOCATED);
}
int coroutine_fn

27
block/nvme.c
View File

@ -128,6 +128,12 @@ struct BDRVNVMeState {
/* PCI address (required for nvme_refresh_filename()) */
char *device;
struct {
uint64_t completion_errors;
uint64_t aligned_accesses;
uint64_t unaligned_accesses;
} stats;
};
#define NVME_BLOCK_OPT_DEVICE "device"
@ -384,6 +390,9 @@ static bool nvme_process_completion(NVMeQueuePair *q)
break;
}
ret = nvme_translate_error(c);
if (ret) {
s->stats.completion_errors++;
}
q->cq.head = (q->cq.head + 1) % NVME_QUEUE_SIZE;
if (!q->cq.head) {
q->cq_phase = !q->cq_phase;
@ -1155,8 +1164,10 @@ static int nvme_co_prw(BlockDriverState *bs, uint64_t offset, uint64_t bytes,
assert(QEMU_IS_ALIGNED(bytes, s->page_size));
assert(bytes <= s->max_transfer);
if (nvme_qiov_aligned(bs, qiov)) {
s->stats.aligned_accesses++;
return nvme_co_prw_aligned(bs, offset, bytes, qiov, is_write, flags);
}
s->stats.unaligned_accesses++;
trace_nvme_prw_buffered(s, offset, bytes, qiov->niov, is_write);
buf = qemu_try_memalign(s->page_size, bytes);
@ -1452,6 +1463,21 @@ static void nvme_unregister_buf(BlockDriverState *bs, void *host)
qemu_vfio_dma_unmap(s->vfio, host);
}
static BlockStatsSpecific *nvme_get_specific_stats(BlockDriverState *bs)
{
BlockStatsSpecific *stats = g_new(BlockStatsSpecific, 1);
BDRVNVMeState *s = bs->opaque;
stats->driver = BLOCKDEV_DRIVER_NVME;
stats->u.nvme = (BlockStatsSpecificNvme) {
.completion_errors = s->stats.completion_errors,
.aligned_accesses = s->stats.aligned_accesses,
.unaligned_accesses = s->stats.unaligned_accesses,
};
return stats;
}
static const char *const nvme_strong_runtime_opts[] = {
NVME_BLOCK_OPT_DEVICE,
NVME_BLOCK_OPT_NAMESPACE,
@ -1485,6 +1511,7 @@ static BlockDriver bdrv_nvme = {
.bdrv_refresh_filename = nvme_refresh_filename,
.bdrv_refresh_limits = nvme_refresh_limits,
.strong_runtime_opts = nvme_strong_runtime_opts,
.bdrv_get_specific_stats = nvme_get_specific_stats,
.bdrv_detach_aio_context = nvme_detach_aio_context,
.bdrv_attach_aio_context = nvme_attach_aio_context,

16
block/qcow2.c
View File

@ -3860,8 +3860,20 @@ static bool is_zero(BlockDriverState *bs, int64_t offset, int64_t bytes)
if (!bytes) {
return true;
}
res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL);
return res >= 0 && (res & BDRV_BLOCK_ZERO) && nr == bytes;
/*
* bdrv_block_status_above doesn't merge different types of zeros, for
* example, zeros which come from the region which is unallocated in
* the whole backing chain, and zeros which come because of a short
* backing file. So, we need a loop.
*/
do {
res = bdrv_block_status_above(bs, NULL, offset, bytes, &nr, NULL, NULL);
offset += nr;
bytes -= nr;
} while (res >= 0 && (res & BDRV_BLOCK_ZERO) && nr && bytes);
return res >= 0 && (res & BDRV_BLOCK_ZERO) && bytes == 0;
}
static coroutine_fn int qcow2_co_pwrite_zeroes(BlockDriverState *bs,

2
contrib/libvhost-user/libvhost-user-glib.c
View File

@ -147,7 +147,7 @@ vug_init(VugDev *dev, uint16_t max_queues, int socket,
g_assert(dev);
g_assert(iface);
if (!vu_init(&dev->parent, max_queues, socket, panic, set_watch,
if (!vu_init(&dev->parent, max_queues, socket, panic, NULL, set_watch,
remove_watch, iface)) {
return false;
}

15
contrib/libvhost-user/libvhost-user.c
View File

@ -68,8 +68,6 @@
/* The version of inflight buffer */
#define INFLIGHT_VERSION 1
#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
/* The version of the protocol we support */
#define VHOST_USER_VERSION 1
#define LIBVHOST_USER_DEBUG 0
@ -268,7 +266,7 @@ have_userfault(void)
}
static bool
vu_message_read(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
vu_message_read_default(VuDev *dev, int conn_fd, VhostUserMsg *vmsg)
{
char control[CMSG_SPACE(VHOST_MEMORY_BASELINE_NREGIONS * sizeof(int))] = {};
struct iovec iov = {
@ -416,7 +414,7 @@ vu_process_message_reply(VuDev *dev, const VhostUserMsg *vmsg)
goto out;
}
if (!vu_message_read(dev, dev->slave_fd, &msg_reply)) {
if (!vu_message_read_default(dev, dev->slave_fd, &msg_reply)) {
goto out;
}
@ -907,7 +905,7 @@ vu_set_mem_table_exec_postcopy(VuDev *dev, VhostUserMsg *vmsg)
/* Wait for QEMU to confirm that it's registered the handler for the
* faults.
*/
if (!vu_message_read(dev, dev->sock, vmsg) ||
if (!dev->read_msg(dev, dev->sock, vmsg) ||
vmsg->size != sizeof(vmsg->payload.u64) ||
vmsg->payload.u64 != 0) {
vu_panic(dev, "failed to receive valid ack for postcopy set-mem-table");
@ -1869,7 +1867,7 @@ vu_dispatch(VuDev *dev)
int reply_requested;
bool need_reply, success = false;
if (!vu_message_read(dev, dev->sock, &vmsg)) {
if (!dev->read_msg(dev, dev->sock, &vmsg)) {
goto end;
}
@ -1920,6 +1918,7 @@ vu_deinit(VuDev *dev)
}
if (vq->kick_fd != -1) {
dev->remove_watch(dev, vq->kick_fd);
close(vq->kick_fd);
vq->kick_fd = -1;
}
@ -1967,6 +1966,7 @@ vu_init(VuDev *dev,
uint16_t max_queues,
int socket,
vu_panic_cb panic,
vu_read_msg_cb read_msg,
vu_set_watch_cb set_watch,
vu_remove_watch_cb remove_watch,
const VuDevIface *iface)
@ -1984,6 +1984,7 @@ vu_init(VuDev *dev,
dev->sock = socket;
dev->panic = panic;
dev->read_msg = read_msg ? read_msg : vu_message_read_default;
dev->set_watch = set_watch;
dev->remove_watch = remove_watch;
dev->iface = iface;
@ -2349,7 +2350,7 @@ static void _vu_queue_notify(VuDev *dev, VuVirtq *vq, bool sync)
vu_message_write(dev, dev->slave_fd, &vmsg);
if (ack) {
vu_message_read(dev, dev->slave_fd, &vmsg);
vu_message_read_default(dev, dev->slave_fd, &vmsg);
}
return;
}

21
contrib/libvhost-user/libvhost-user.h
View File

@ -36,6 +36,8 @@
*/
#define VHOST_USER_MAX_RAM_SLOTS 32
#define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64)
typedef enum VhostSetConfigType {
VHOST_SET_CONFIG_TYPE_MASTER = 0,
VHOST_SET_CONFIG_TYPE_MIGRATION = 1,
@ -221,6 +223,7 @@ typedef uint64_t (*vu_get_features_cb) (VuDev *dev);
typedef void (*vu_set_features_cb) (VuDev *dev, uint64_t features);
typedef int (*vu_process_msg_cb) (VuDev *dev, VhostUserMsg *vmsg,
int *do_reply);
typedef bool (*vu_read_msg_cb) (VuDev *dev, int sock, VhostUserMsg *vmsg);
typedef void (*vu_queue_set_started_cb) (VuDev *dev, int qidx, bool started);
typedef bool (*vu_queue_is_processed_in_order_cb) (VuDev *dev, int qidx);
typedef int (*vu_get_config_cb) (VuDev *dev, uint8_t *config, uint32_t len);
@ -389,6 +392,23 @@ struct VuDev {
bool broken;
uint16_t max_queues;
/* @read_msg: custom method to read vhost-user message
*
* Read data from vhost_user socket fd and fill up
* the passed VhostUserMsg *vmsg struct.
*
* If reading fails, it should close the received set of file
* descriptors as socket message's auxiliary data.
*
* For the details, please refer to vu_message_read in libvhost-user.c
* which will be used by default if not custom method is provided when
* calling vu_init
*
* Returns: true if vhost-user message successfully received,
* otherwise return false.
*
*/
vu_read_msg_cb read_msg;
/* @set_watch: add or update the given fd to the watch set,
* call cb when condition is met */
vu_set_watch_cb set_watch;
@ -432,6 +452,7 @@ bool vu_init(VuDev *dev,
uint16_t max_queues,
int socket,
vu_panic_cb panic,
vu_read_msg_cb read_msg,
vu_set_watch_cb set_watch,
vu_remove_watch_cb remove_watch,
const VuDevIface *iface);

1
contrib/libvhost-user/meson.build
View File

@ -1,3 +1,4 @@
libvhost_user = static_library('vhost-user',
files('libvhost-user.c', 'libvhost-user-glib.c'),
build_by_default: false)
vhost_user = declare_dependency(link_with: libvhost_user)

31
hw/core/qdev-properties-system.c
View File

@ -30,6 +30,7 @@
#include "sysemu/blockdev.h"
#include "net/net.h"
#include "hw/pci/pci.h"
#include "util/block-helpers.h"
static bool check_prop_still_unset(DeviceState *dev, const char *name,
const void *old_val, const char *new_val,
@ -576,16 +577,6 @@ const PropertyInfo qdev_prop_losttickpolicy = {
/* --- blocksize --- */
/* lower limit is sector size */
#define MIN_BLOCK_SIZE 512
#define MIN_BLOCK_SIZE_STR "512 B"
/*
* upper limit is arbitrary, 2 MiB looks sufficient for all sensible uses, and
* matches qcow2 cluster size limit
*/
#define MAX_BLOCK_SIZE (2 * MiB)
#define MAX_BLOCK_SIZE_STR "2 MiB"
static void set_blocksize(Object *obj, Visitor *v, const char *name,
void *opaque, Error **errp)
{
@ -593,6 +584,7 @@ static void set_blocksize(Object *obj, Visitor *v, const char *name,
Property *prop = opaque;
uint32_t *ptr = qdev_get_prop_ptr(dev, prop);
uint64_t value;
Error *local_err = NULL;
if (dev->realized) {
qdev_prop_set_after_realize(dev, name, errp);
@ -602,24 +594,11 @@ static void set_blocksize(Object *obj, Visitor *v, const char *name,
if (!visit_type_size(v, name, &value, errp)) {
return;
}
/* value of 0 means "unset" */
if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
error_setg(errp,
"Property %s.%s doesn't take value %" PRIu64
" (minimum: " MIN_BLOCK_SIZE_STR
", maximum: " MAX_BLOCK_SIZE_STR ")",
dev->id ? : "", name, value);
check_block_size(dev->id ? : "", name, value, &local_err);
if (local_err) {
error_propagate(errp, local_err);
return;
}
/* We rely on power-of-2 blocksizes for bitmasks */
if ((value & (value - 1)) != 0) {
error_setg(errp,
"Property %s.%s doesn't take value '%" PRId64 "', "
"it's not a power of 2", dev->id ?: "", name, (int64_t)value);
return;
}
*ptr = value;
}

65
include/qemu/vhost-user-server.h Normal file
View File

@ -0,0 +1,65 @@
/*
* Sharing QEMU devices via vhost-user protocol
*
* Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
* Copyright (c) 2020 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*/
#ifndef VHOST_USER_SERVER_H
#define VHOST_USER_SERVER_H
#include "contrib/libvhost-user/libvhost-user.h"
#include "io/channel-socket.h"
#include "io/channel-file.h"
#include "io/net-listener.h"
#include "qemu/error-report.h"
#include "qapi/error.h"
#include "standard-headers/linux/virtio_blk.h"
/* A kick fd that we monitor on behalf of libvhost-user */
typedef struct VuFdWatch {
VuDev *vu_dev;
int fd; /*kick fd*/
void *pvt;
vu_watch_cb cb;
QTAILQ_ENTRY(VuFdWatch) next;
} VuFdWatch;
/**
* VuServer:
* A vhost-user server instance with user-defined VuDevIface callbacks.
* Vhost-user device backends can be implemented using VuServer. VuDevIface
* callbacks and virtqueue kicks run in the given AioContext.
*/
typedef struct {
QIONetListener *listener;
QEMUBH *restart_listener_bh;
AioContext *ctx;
int max_queues;
const VuDevIface *vu_iface;
/* Protected by ctx lock */
VuDev vu_dev;
QIOChannel *ioc; /* The I/O channel with the client */
QIOChannelSocket *sioc; /* The underlying data channel with the client */
QTAILQ_HEAD(, VuFdWatch) vu_fd_watches;
Coroutine *co_trip; /* coroutine for processing VhostUserMsg */
} VuServer;
bool vhost_user_server_start(VuServer *server,
SocketAddress *unix_socket,
AioContext *ctx,
uint16_t max_queues,
const VuDevIface *vu_iface,
Error **errp);
void vhost_user_server_stop(VuServer *server);
void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx);
void vhost_user_server_detach_aio_context(VuServer *server);
#endif /* VHOST_USER_SERVER_H */

22
meson.build
View File

@ -1398,6 +1398,11 @@ trace_events_subdirs += [
'util',
]
vhost_user = not_found
if 'CONFIG_VHOST_USER' in config_host
subdir('contrib/libvhost-user')
endif
subdir('qapi')
subdir('qobject')
subdir('stubs')
@ -1438,7 +1443,6 @@ subdir('dump')
block_ss.add(files(
'block.c',
'blockdev-nbd.c',
'blockjob.c',
'job.c',
'qemu-io-cmds.c',
@ -1451,6 +1455,7 @@ subdir('block')
blockdev_ss.add(files(
'blockdev.c',
'blockdev-nbd.c',
'iothread.c',
'job-qmp.c',
))
@ -1459,7 +1464,6 @@ blockdev_ss.add(files(
# os-win32.c does not
blockdev_ss.add(when: 'CONFIG_POSIX', if_true: files('os-posix.c'))
softmmu_ss.add(when: 'CONFIG_WIN32', if_true: [files('os-win32.c')])
softmmu_ss.add_all(blockdev_ss)
common_ss.add(files('cpus-common.c'))
@ -1591,6 +1595,15 @@ block = declare_dependency(link_whole: [libblock],
link_args: '@block.syms',
dependencies: [crypto, io])
blockdev_ss = blockdev_ss.apply(config_host, strict: false)
libblockdev = static_library('blockdev', blockdev_ss.sources() + genh,
dependencies: blockdev_ss.dependencies(),
name_suffix: 'fa',
build_by_default: false)
blockdev = declare_dependency(link_whole: [libblockdev],
dependencies: [block])
qmp_ss = qmp_ss.apply(config_host, strict: false)
libqmp = static_library('qmp', qmp_ss.sources() + genh,
dependencies: qmp_ss.dependencies(),
@ -1623,7 +1636,7 @@ foreach m : block_mods + softmmu_mods
install_dir: config_host['qemu_moddir'])
endforeach
softmmu_ss.add(authz, block, chardev, crypto, io, qmp)
softmmu_ss.add(authz, blockdev, chardev, crypto, io, qmp)
common_ss.add(qom, qemuutil)
common_ss.add_all(when: 'CONFIG_SOFTMMU', if_true: [softmmu_ss])
@ -1819,7 +1832,7 @@ if have_tools
qemu_io = executable('qemu-io', files('qemu-io.c'),
dependencies: [block, qemuutil], install: true)
qemu_nbd = executable('qemu-nbd', files('qemu-nbd.c'),
dependencies: [block, qemuutil], install: true)
dependencies: [blockdev, qemuutil], install: true)
subdir('storage-daemon')
subdir('contrib/rdmacm-mux')
@ -1830,7 +1843,6 @@ if have_tools
install: true)
if 'CONFIG_VHOST_USER' in config_host
subdir('contrib/libvhost-user')
subdir('contrib/vhost-user-blk')
subdir('contrib/vhost-user-gpu')
subdir('contrib/vhost-user-input')

2
nbd/meson.build
View File

@ -1,5 +1,7 @@
block_ss.add(files(
'client.c',
'common.c',
))
blockdev_ss.add(files(
'server.c',
))

2
nbd/server.c
View File

@ -1517,8 +1517,6 @@ static int nbd_export_create(BlockExport *blk_exp, BlockExportOptions *exp_args,
return ret;
}
blk_set_allow_aio_context_change(blk, true);
QTAILQ_INIT(&exp->clients);
exp->name = g_strdup(arg->name);
exp->description = g_strdup(arg->description);

24
qapi/block-core.json
View File

@ -947,6 +947,27 @@
'discard-nb-failed': 'uint64',
'discard-bytes-ok': 'uint64' } }
##
# @BlockStatsSpecificNvme:
#
# NVMe driver statistics
#
# @completion-errors: The number of completion errors.
#
# @aligned-accesses: The number of aligned accesses performed by
# the driver.
#
# @unaligned-accesses: The number of unaligned accesses performed by
# the driver.
#
# Since: 5.2
##
{ 'struct': 'BlockStatsSpecificNvme',
'data': {
'completion-errors': 'uint64',
'aligned-accesses': 'uint64',
'unaligned-accesses': 'uint64' } }
##
# @BlockStatsSpecific:
#
@ -959,7 +980,8 @@
'discriminator': 'driver',
'data': {
'file': 'BlockStatsSpecificFile',
'host_device': 'BlockStatsSpecificFile' } }
'host_device': 'BlockStatsSpecificFile',
'nvme': 'BlockStatsSpecificNvme' } }
##
# @BlockStats:

36
qapi/block-export.json
View File

@ -84,6 +84,25 @@
'data': { '*name': 'str', '*description': 'str',
'*bitmap': 'str' } }
##
# @BlockExportOptionsVhostUserBlk:
#
# A vhost-user-blk block export.
#
# @addr: The vhost-user socket on which to listen. Both 'unix' and 'fd'
# SocketAddress types are supported. Passed fds must be UNIX domain
# sockets.
# @logical-block-size: Logical block size in bytes. Defaults to 512 bytes.
# @num-queues: Number of request virtqueues. Must be greater than 0. Defaults
# to 1.
#
# Since: 5.2
##
{ 'struct': 'BlockExportOptionsVhostUserBlk',
'data': { 'addr': 'SocketAddress',
'*logical-block-size': 'size',
'*num-queues': 'uint16'} }
##
# @NbdServerAddOptions:
#
@ -180,11 +199,12 @@
# An enumeration of block export types
#
# @nbd: NBD export
# @vhost-user-blk: vhost-user-blk export (since 5.2)
#
# Since: 4.2
##
{ 'enum': 'BlockExportType',
'data': [ 'nbd' ] }
'data': [ 'nbd', 'vhost-user-blk' ] }
##
# @BlockExportOptions:
@ -203,17 +223,29 @@
# export before completion is signalled. (since: 5.2;
# default: false)
#
# @iothread: The name of the iothread object where the export will run. The
# default is to use the thread currently associated with the
# block node. (since: 5.2)
#
# @fixed-iothread: True prevents the block node from being moved to another
# thread while the export is active. If true and @iothread is
# given, export creation fails if the block node cannot be
# moved to the iothread. The default is false. (since: 5.2)
#
# Since: 4.2
##
{ 'union': 'BlockExportOptions',
'base': { 'type': 'BlockExportType',
'id': 'str',
'*fixed-iothread': 'bool',
'*iothread': 'str',
'node-name': 'str',
'*writable': 'bool',
'*writethrough': 'bool' },
'discriminator': 'type',
'data': {
'nbd': 'BlockExportOptionsNbd'
'nbd': 'BlockExportOptionsNbd',
'vhost-user-blk': 'BlockExportOptionsVhostUserBlk'
} }
##

21
qemu-nbd.c
View File

@ -25,6 +25,7 @@
#include "qapi/error.h"
#include "qemu/cutils.h"
#include "sysemu/block-backend.h"
#include "sysemu/runstate.h" /* for qemu_system_killed() prototype */
#include "block/block_int.h"
#include "block/nbd.h"
#include "qemu/main-loop.h"
@ -155,7 +156,11 @@ QEMU_COPYRIGHT "\n"
}
#ifdef CONFIG_POSIX
static void termsig_handler(int signum)
/*
* The client thread uses SIGTERM to interrupt the server. A signal
* handler ensures that "qemu-nbd -v -c" exits with a nice status code.
*/
void qemu_system_killed(int signum, pid_t pid)
{
qatomic_cmpxchg(&state, RUNNING, TERMINATE);
qemu_notify_event();
@ -582,18 +587,8 @@ int main(int argc, char **argv)
BlockExportOptions *export_opts;
#ifdef CONFIG_POSIX
/*
* Exit gracefully on various signals, which includes SIGTERM used
* by 'qemu-nbd -v -c'.
*/
struct sigaction sa_sigterm;
memset(&sa_sigterm, 0, sizeof(sa_sigterm));
sa_sigterm.sa_handler = termsig_handler;
sigaction(SIGTERM, &sa_sigterm, NULL);
sigaction(SIGINT, &sa_sigterm, NULL);
sigaction(SIGHUP, &sa_sigterm, NULL);
signal(SIGPIPE, SIG_IGN);
os_setup_early_signal_handling();
os_setup_signal_handling();
#endif
socket_init();

4
softmmu/vl.c
View File

@ -2540,6 +2540,10 @@ static bool object_create_initial(const char *type, QemuOpts *opts)
}
#endif
/* Reason: vhost-user-blk-server property "node-name" */
if (g_str_equal(type, "vhost-user-blk-server")) {
return false;
}
/*
* Reason: filter-* property "netdev" etc.
*/

3
storage-daemon/meson.build
View File

@ -1,7 +1,6 @@
qsd_ss = ss.source_set()
qsd_ss.add(files('qemu-storage-daemon.c'))
qsd_ss.add(block, chardev, qmp, qom, qemuutil)
qsd_ss.add_all(blockdev_ss)
qsd_ss.add(blockdev, chardev, qmp, qom, qemuutil)
subdir('qapi')

7
stubs/blk-exp-close-all.c Normal file
View File

@ -0,0 +1,7 @@
#include "qemu/osdep.h"
#include "block/export.h"
/* Only used in programs that support block exports (libblockdev.fa) */
void blk_exp_close_all(void)
{
}

1
stubs/meson.build
View File

@ -1,6 +1,7 @@
stub_ss.add(files('arch_type.c'))
stub_ss.add(files('bdrv-next-monitor-owned.c'))
stub_ss.add(files('blk-commit-all.c'))
stub_ss.add(files('blk-exp-close-all.c'))
stub_ss.add(files('blockdev-close-all-bdrv-states.c'))
stub_ss.add(files('change-state-handler.c'))
stub_ss.add(files('cmos.c'))

20
tests/qemu-iotests/274
View File

@ -115,6 +115,26 @@ with iotests.FilePath('base') as base, \
iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, mid)
iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), mid)
iotests.log('=== Testing qemu-img commit (top -> base) ===')
create_chain()
iotests.qemu_img_log('commit', '-b', base, top)
iotests.img_info_log(base)
iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, base)
iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), base)
iotests.log('=== Testing QMP active commit (top -> base) ===')
create_chain()
with create_vm() as vm:
vm.launch()
vm.qmp_log('block-commit', device='top', base_node='base',
job_id='job0', auto_dismiss=False)
vm.run_job('job0', wait=5)
iotests.img_info_log(mid)
iotests.qemu_io_log('-c', 'read -P 1 0 %d' % size_short, base)
iotests.qemu_io_log('-c', 'read -P 0 %d %d' % (size_short, size_diff), base)
iotests.log('== Resize tests ==')

68
tests/qemu-iotests/274.out
View File

@ -135,6 +135,74 @@ read 1048576/1048576 bytes at offset 0
read 1048576/1048576 bytes at offset 1048576
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
=== Testing qemu-img commit (top -> base) ===
Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 lazy_refcounts=off refcount_bits=16
Formatting 'TEST_DIR/PID-mid', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=1048576 backing_file=TEST_DIR/PID-base backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
Formatting 'TEST_DIR/PID-top', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 backing_file=TEST_DIR/PID-mid backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
wrote 2097152/2097152 bytes at offset 0
2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
Image committed.
image: TEST_IMG
file format: IMGFMT
virtual size: 2 MiB (2097152 bytes)
cluster_size: 65536
Format specific information:
compat: 1.1
compression type: zlib
lazy refcounts: false
refcount bits: 16
corrupt: false
extended l2: false
read 1048576/1048576 bytes at offset 0
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
read 1048576/1048576 bytes at offset 1048576
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
=== Testing QMP active commit (top -> base) ===
Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 lazy_refcounts=off refcount_bits=16
Formatting 'TEST_DIR/PID-mid', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=1048576 backing_file=TEST_DIR/PID-base backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
Formatting 'TEST_DIR/PID-top', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=2097152 backing_file=TEST_DIR/PID-mid backing_fmt=qcow2 lazy_refcounts=off refcount_bits=16
wrote 2097152/2097152 bytes at offset 0
2 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
{"execute": "block-commit", "arguments": {"auto-dismiss": false, "base-node": "base", "device": "top", "job-id": "job0"}}
{"return": {}}
{"execute": "job-complete", "arguments": {"id": "job0"}}
{"return": {}}
{"data": {"device": "job0", "len": 1048576, "offset": 1048576, "speed": 0, "type": "commit"}, "event": "BLOCK_JOB_READY", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
{"data": {"device": "job0", "len": 1048576, "offset": 1048576, "speed": 0, "type": "commit"}, "event": "BLOCK_JOB_COMPLETED", "timestamp": {"microseconds": "USECS", "seconds": "SECS"}}
{"execute": "job-dismiss", "arguments": {"id": "job0"}}
{"return": {}}
image: TEST_IMG
file format: IMGFMT
virtual size: 1 MiB (1048576 bytes)
cluster_size: 65536
backing file: TEST_DIR/PID-base
backing file format: IMGFMT
Format specific information:
compat: 1.1
compression type: zlib
lazy refcounts: false
refcount bits: 16
corrupt: false
extended l2: false
read 1048576/1048576 bytes at offset 0
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
read 1048576/1048576 bytes at offset 1048576
1 MiB, X ops; XX:XX:XX.X (XXX YYY/sec and XXX ops/sec)
== Resize tests ==
=== preallocation=off ===
Formatting 'TEST_DIR/PID-base', fmt=qcow2 cluster_size=65536 extended_l2=off compression_type=zlib size=6442450944 lazy_refcounts=off refcount_bits=16

2
tests/vhost-user-bridge.c
View File

@ -520,6 +520,7 @@ vubr_accept_cb(int sock, void *ctx)
VHOST_USER_BRIDGE_MAX_QUEUES,
conn_fd,
vubr_panic,
NULL,
vubr_set_watch,
vubr_remove_watch,
&vuiface)) {
@ -573,6 +574,7 @@ vubr_new(const char *path, bool client)
VHOST_USER_BRIDGE_MAX_QUEUES,
dev->sock,
vubr_panic,
NULL,
vubr_set_watch,
vubr_remove_watch,
&vuiface)) {

4
tools/virtiofsd/fuse_virtio.c
View File

@ -1013,8 +1013,8 @@ int virtio_session_mount(struct fuse_session *se)
se->vu_socketfd = data_sock;
se->virtio_dev->se = se;
pthread_rwlock_init(&se->virtio_dev->vu_dispatch_rwlock, NULL);
vu_init(&se->virtio_dev->dev, 2, se->vu_socketfd, fv_panic, fv_set_watch,
fv_remove_watch, &fv_iface);
vu_init(&se->virtio_dev->dev, 2, se->vu_socketfd, fv_panic, NULL,
fv_set_watch, fv_remove_watch, &fv_iface);
return 0;
}

46
util/block-helpers.c Normal file
View File

@ -0,0 +1,46 @@
/*
* Block utility functions
*
* Copyright IBM, Corp. 2011
* Copyright (c) 2020 Coiby Xu <coiby.xu@gmail.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qapi/error.h"
#include "qapi/qmp/qerror.h"
#include "block-helpers.h"
/**
* check_block_size:
* @id: The unique ID of the object
* @name: The name of the property being validated
* @value: The block size in bytes
* @errp: A pointer to an area to store an error
*
* This function checks that the block size meets the following conditions:
* 1. At least MIN_BLOCK_SIZE
* 2. No larger than MAX_BLOCK_SIZE
* 3. A power of 2
*/
void check_block_size(const char *id, const char *name, int64_t value,
Error **errp)
{
/* value of 0 means "unset" */
if (value && (value < MIN_BLOCK_SIZE || value > MAX_BLOCK_SIZE)) {
error_setg(errp, QERR_PROPERTY_VALUE_OUT_OF_RANGE,
id, name, value, MIN_BLOCK_SIZE, MAX_BLOCK_SIZE);
return;
}
/* We rely on power-of-2 blocksizes for bitmasks */
if ((value & (value - 1)) != 0) {
error_setg(errp,
"Property %s.%s doesn't take value '%" PRId64
"', it's not a power of 2",
id, name, value);
return;
}
}

19
util/block-helpers.h Normal file
View File

@ -0,0 +1,19 @@
#ifndef BLOCK_HELPERS_H
#define BLOCK_HELPERS_H
#include "qemu/units.h"
/* lower limit is sector size */
#define MIN_BLOCK_SIZE INT64_C(512)
#define MIN_BLOCK_SIZE_STR "512 B"
/*
* upper limit is arbitrary, 2 MiB looks sufficient for all sensible uses, and
* matches qcow2 cluster size limit
*/
#define MAX_BLOCK_SIZE (2 * MiB)
#define MAX_BLOCK_SIZE_STR "2 MiB"
void check_block_size(const char *id, const char *name, int64_t value,
Error **errp);
#endif /* BLOCK_HELPERS_H */

4
util/meson.build
View File

@ -66,6 +66,10 @@ if have_block
util_ss.add(files('main-loop.c'))
util_ss.add(files('nvdimm-utils.c'))
util_ss.add(files('qemu-coroutine.c', 'qemu-coroutine-lock.c', 'qemu-coroutine-io.c'))
util_ss.add(when: ['CONFIG_LINUX', 'CONFIG_VHOST_USER'], if_true: [
files('vhost-user-server.c'), vhost_user
])
util_ss.add(files('block-helpers.c'))
util_ss.add(files('qemu-coroutine-sleep.c'))
util_ss.add(files('qemu-co-shared-resource.c'))
util_ss.add(files('thread-pool.c', 'qemu-timer.c'))

446
util/vhost-user-server.c Normal file
View File

@ -0,0 +1,446 @@
/*
* Sharing QEMU devices via vhost-user protocol
*
* Copyright (c) Coiby Xu <coiby.xu@gmail.com>.
* Copyright (c) 2020 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU GPL, version 2 or
* later. See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "qemu/main-loop.h"
#include "qemu/vhost-user-server.h"
#include "block/aio-wait.h"
/*
* Theory of operation:
*
* VuServer is started and stopped by vhost_user_server_start() and
* vhost_user_server_stop() from the main loop thread. Starting the server
* opens a vhost-user UNIX domain socket and listens for incoming connections.
* Only one connection is allowed at a time.
*
* The connection is handled by the vu_client_trip() coroutine in the
* VuServer->ctx AioContext. The coroutine consists of a vu_dispatch() loop
* where libvhost-user calls vu_message_read() to receive the next vhost-user
* protocol messages over the UNIX domain socket.
*
* When virtqueues are set up libvhost-user calls set_watch() to monitor kick
* fds. These fds are also handled in the VuServer->ctx AioContext.
*
* Both vu_client_trip() and kick fd monitoring can be stopped by shutting down
* the socket connection. Shutting down the socket connection causes
* vu_message_read() to fail since no more data can be received from the socket.
* After vu_dispatch() fails, vu_client_trip() calls vu_deinit() to stop
* libvhost-user before terminating the coroutine. vu_deinit() calls
* remove_watch() to stop monitoring kick fds and this stops virtqueue
* processing.
*
* When vu_client_trip() has finished cleaning up it schedules a BH in the main
* loop thread to accept the next client connection.
*
* When libvhost-user detects an error it calls panic_cb() and sets the
* dev->broken flag. Both vu_client_trip() and kick fd processing stop when
* the dev->broken flag is set.
*
* It is possible to switch AioContexts using
* vhost_user_server_detach_aio_context() and
* vhost_user_server_attach_aio_context(). They stop monitoring fds in the old
* AioContext and resume monitoring in the new AioContext. The vu_client_trip()
* coroutine remains in a yielded state during the switch. This is made
* possible by QIOChannel's support for spurious coroutine re-entry in
* qio_channel_yield(). The coroutine will restart I/O when re-entered from the
* new AioContext.
*/
static void vmsg_close_fds(VhostUserMsg *vmsg)
{
int i;
for (i = 0; i < vmsg->fd_num; i++) {
close(vmsg->fds[i]);
}
}
static void vmsg_unblock_fds(VhostUserMsg *vmsg)
{
int i;
for (i = 0; i < vmsg->fd_num; i++) {
qemu_set_nonblock(vmsg->fds[i]);
}
}
static void panic_cb(VuDev *vu_dev, const char *buf)
{
error_report("vu_panic: %s", buf);
}
static bool coroutine_fn
vu_message_read(VuDev *vu_dev, int conn_fd, VhostUserMsg *vmsg)
{
struct iovec iov = {
.iov_base = (char *)vmsg,
.iov_len = VHOST_USER_HDR_SIZE,
};
int rc, read_bytes = 0;
Error *local_err = NULL;
const size_t max_fds = G_N_ELEMENTS(vmsg->fds);
VuServer *server = container_of(vu_dev, VuServer, vu_dev);
QIOChannel *ioc = server->ioc;
vmsg->fd_num = 0;
if (!ioc) {
error_report_err(local_err);
goto fail;
}
assert(qemu_in_coroutine());
do {
size_t nfds = 0;
int *fds = NULL;
/*
* qio_channel_readv_full may have short reads, keeping calling it
* until getting VHOST_USER_HDR_SIZE or 0 bytes in total
*/
rc = qio_channel_readv_full(ioc, &iov, 1, &fds, &nfds, &local_err);
if (rc < 0) {
if (rc == QIO_CHANNEL_ERR_BLOCK) {
assert(local_err == NULL);
qio_channel_yield(ioc, G_IO_IN);
continue;
} else {
error_report_err(local_err);
goto fail;
}
}
if (nfds > 0) {
if (vmsg->fd_num + nfds > max_fds) {
error_report("A maximum of %zu fds are allowed, "
"however got %zu fds now",
max_fds, vmsg->fd_num + nfds);
g_free(fds);
goto fail;
}
memcpy(vmsg->fds + vmsg->fd_num, fds, nfds * sizeof(vmsg->fds[0]));
vmsg->fd_num += nfds;
g_free(fds);
}
if (rc == 0) { /* socket closed */
goto fail;
}
iov.iov_base += rc;
iov.iov_len -= rc;
read_bytes += rc;
} while (read_bytes != VHOST_USER_HDR_SIZE);
/* qio_channel_readv_full will make socket fds blocking, unblock them */
vmsg_unblock_fds(vmsg);
if (vmsg->size > sizeof(vmsg->payload)) {
error_report("Error: too big message request: %d, "
"size: vmsg->size: %u, "
"while sizeof(vmsg->payload) = %zu",
vmsg->request, vmsg->size, sizeof(vmsg->payload));
goto fail;
}
struct iovec iov_payload = {
.iov_base = (char *)&vmsg->payload,
.iov_len = vmsg->size,
};
if (vmsg->size) {
rc = qio_channel_readv_all_eof(ioc, &iov_payload, 1, &local_err);
if (rc != 1) {
if (local_err) {
error_report_err(local_err);
}
goto fail;
}
}
return true;
fail:
vmsg_close_fds(vmsg);
return false;
}
static coroutine_fn void vu_client_trip(void *opaque)
{
VuServer *server = opaque;
VuDev *vu_dev = &server->vu_dev;
while (!vu_dev->broken && vu_dispatch(vu_dev)) {
/* Keep running */
}
vu_deinit(vu_dev);
/* vu_deinit() should have called remove_watch() */
assert(QTAILQ_EMPTY(&server->vu_fd_watches));
object_unref(OBJECT(server->sioc));
server->sioc = NULL;
object_unref(OBJECT(server->ioc));
server->ioc = NULL;
server->co_trip = NULL;
if (server->restart_listener_bh) {
qemu_bh_schedule(server->restart_listener_bh);
}
aio_wait_kick();
}
/*
* a wrapper for vu_kick_cb
*
* since aio_dispatch can only pass one user data pointer to the
* callback function, pack VuDev and pvt into a struct. Then unpack it
* and pass them to vu_kick_cb
*/
static void kick_handler(void *opaque)
{
VuFdWatch *vu_fd_watch = opaque;
VuDev *vu_dev = vu_fd_watch->vu_dev;
vu_fd_watch->cb(vu_dev, 0, vu_fd_watch->pvt);
/* Stop vu_client_trip() if an error occurred in vu_fd_watch->cb() */
if (vu_dev->broken) {
VuServer *server = container_of(vu_dev, VuServer, vu_dev);
qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
}
}
static VuFdWatch *find_vu_fd_watch(VuServer *server, int fd)
{
VuFdWatch *vu_fd_watch, *next;
QTAILQ_FOREACH_SAFE(vu_fd_watch, &server->vu_fd_watches, next, next) {
if (vu_fd_watch->fd == fd) {
return vu_fd_watch;
}
}
return NULL;
}
static void
set_watch(VuDev *vu_dev, int fd, int vu_evt,
vu_watch_cb cb, void *pvt)
{
VuServer *server = container_of(vu_dev, VuServer, vu_dev);
g_assert(vu_dev);
g_assert(fd >= 0);
g_assert(cb);
VuFdWatch *vu_fd_watch = find_vu_fd_watch(server, fd);
if (!vu_fd_watch) {
VuFdWatch *vu_fd_watch = g_new0(VuFdWatch, 1);
QTAILQ_INSERT_TAIL(&server->vu_fd_watches, vu_fd_watch, next);
vu_fd_watch->fd = fd;
vu_fd_watch->cb = cb;
qemu_set_nonblock(fd);
aio_set_fd_handler(server->ioc->ctx, fd, true, kick_handler,
NULL, NULL, vu_fd_watch);
vu_fd_watch->vu_dev = vu_dev;
vu_fd_watch->pvt = pvt;
}
}
static void remove_watch(VuDev *vu_dev, int fd)
{
VuServer *server;
g_assert(vu_dev);
g_assert(fd >= 0);
server = container_of(vu_dev, VuServer, vu_dev);
VuFdWatch *vu_fd_watch = find_vu_fd_watch(server, fd);
if (!vu_fd_watch) {
return;
}
aio_set_fd_handler(server->ioc->ctx, fd, true, NULL, NULL, NULL, NULL);
QTAILQ_REMOVE(&server->vu_fd_watches, vu_fd_watch, next);
g_free(vu_fd_watch);
}
static void vu_accept(QIONetListener *listener, QIOChannelSocket *sioc,
gpointer opaque)
{
VuServer *server = opaque;
if (server->sioc) {
warn_report("Only one vhost-user client is allowed to "
"connect the server one time");
return;
}
if (!vu_init(&server->vu_dev, server->max_queues, sioc->fd, panic_cb,
vu_message_read, set_watch, remove_watch, server->vu_iface)) {
error_report("Failed to initialize libvhost-user");
return;
}
/*
* Unset the callback function for network listener to make another
* vhost-user client keeping waiting until this client disconnects
*/
qio_net_listener_set_client_func(server->listener,
NULL,
NULL,
NULL);
server->sioc = sioc;
/*
* Increase the object reference, so sioc will not freed by
* qio_net_listener_channel_func which will call object_unref(OBJECT(sioc))
*/
object_ref(OBJECT(server->sioc));
qio_channel_set_name(QIO_CHANNEL(sioc), "vhost-user client");
server->ioc = QIO_CHANNEL(sioc);
object_ref(OBJECT(server->ioc));
/* TODO vu_message_write() spins if non-blocking! */
qio_channel_set_blocking(server->ioc, false, NULL);
server->co_trip = qemu_coroutine_create(vu_client_trip, server);
aio_context_acquire(server->ctx);
vhost_user_server_attach_aio_context(server, server->ctx);
aio_context_release(server->ctx);
}
void vhost_user_server_stop(VuServer *server)
{
aio_context_acquire(server->ctx);
qemu_bh_delete(server->restart_listener_bh);
server->restart_listener_bh = NULL;
if (server->sioc) {
VuFdWatch *vu_fd_watch;
QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
NULL, NULL, NULL, vu_fd_watch);
}
qio_channel_shutdown(server->ioc, QIO_CHANNEL_SHUTDOWN_BOTH, NULL);
AIO_WAIT_WHILE(server->ctx, server->co_trip);
}
aio_context_release(server->ctx);
if (server->listener) {
qio_net_listener_disconnect(server->listener);
object_unref(OBJECT(server->listener));
}
}
/*
* Allow the next client to connect to the server. Called from a BH in the main
* loop.
*/
static void restart_listener_bh(void *opaque)
{
VuServer *server = opaque;
qio_net_listener_set_client_func(server->listener, vu_accept, server,
NULL);
}
/* Called with ctx acquired */
void vhost_user_server_attach_aio_context(VuServer *server, AioContext *ctx)
{
VuFdWatch *vu_fd_watch;
server->ctx = ctx;
if (!server->sioc) {
return;
}
qio_channel_attach_aio_context(server->ioc, ctx);
QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
aio_set_fd_handler(ctx, vu_fd_watch->fd, true, kick_handler, NULL,
NULL, vu_fd_watch);
}
aio_co_schedule(ctx, server->co_trip);
}
/* Called with server->ctx acquired */
void vhost_user_server_detach_aio_context(VuServer *server)
{
if (server->sioc) {
VuFdWatch *vu_fd_watch;
QTAILQ_FOREACH(vu_fd_watch, &server->vu_fd_watches, next) {
aio_set_fd_handler(server->ctx, vu_fd_watch->fd, true,
NULL, NULL, NULL, vu_fd_watch);
}
qio_channel_detach_aio_context(server->ioc);
}
server->ctx = NULL;
}
bool vhost_user_server_start(VuServer *server,
SocketAddress *socket_addr,
AioContext *ctx,
uint16_t max_queues,
const VuDevIface *vu_iface,
Error **errp)
{
QEMUBH *bh;
QIONetListener *listener;
if (socket_addr->type != SOCKET_ADDRESS_TYPE_UNIX &&
socket_addr->type != SOCKET_ADDRESS_TYPE_FD) {
error_setg(errp, "Only socket address types 'unix' and 'fd' are supported");
return false;
}
listener = qio_net_listener_new();
if (qio_net_listener_open_sync(listener, socket_addr, 1,
errp) < 0) {
object_unref(OBJECT(listener));
return false;
}
bh = qemu_bh_new(restart_listener_bh, server);
/* zero out unspecified fields */
*server = (VuServer) {
.listener = listener,
.restart_listener_bh = bh,
.vu_iface = vu_iface,
.max_queues = max_queues,
.ctx = ctx,
};
qio_net_listener_set_name(server->listener, "vhost-user-backend-listener");
qio_net_listener_set_client_func(server->listener,
vu_accept,
server,
NULL);
QTAILQ_INIT(&server->vu_fd_watches);
return true;
}