#include "trace.h"
#include "sysemu/block-backend.h"
#include "block/blockjob.h"
+#include "block/blockjob_int.h"
#include "block/block_int.h"
#include "qemu/cutils.h"
#include "qapi/error.h"
#define NOT_DONE 0x7fffffff /* used while emulated sync operation in progress */
-static BlockAIOCB *bdrv_co_aio_prw_vector(BdrvChild *child,
- int64_t offset,
- QEMUIOVector *qiov,
- BdrvRequestFlags flags,
- BlockCompletionFunc *cb,
- void *opaque,
- bool is_write);
-static void coroutine_fn bdrv_co_do_rw(void *opaque);
static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs,
- int64_t offset, int count, BdrvRequestFlags flags);
+ int64_t offset, int bytes, BdrvRequestFlags flags);
void bdrv_parent_drained_begin(BlockDriverState *bs)
{
*/
void bdrv_enable_copy_on_read(BlockDriverState *bs)
{
- bs->copy_on_read++;
+ atomic_inc(&bs->copy_on_read);
}
void bdrv_disable_copy_on_read(BlockDriverState *bs)
{
- assert(bs->copy_on_read > 0);
- bs->copy_on_read--;
+ int old = atomic_fetch_dec(&bs->copy_on_read);
+ assert(old >= 1);
}
/* Check if any requests are in-flight (including throttled requests) */
static bool bdrv_drain_recurse(BlockDriverState *bs)
{
- BdrvChild *child;
+ BdrvChild *child, *tmp;
bool waited;
waited = BDRV_POLL_WHILE(bs, atomic_read(&bs->in_flight) > 0);
bs->drv->bdrv_drain(bs);
}
- QLIST_FOREACH(child, &bs->children, next) {
- waited |= bdrv_drain_recurse(child->bs);
+ QLIST_FOREACH_SAFE(child, &bs->children, next, tmp) {
+ BlockDriverState *bs = child->bs;
+ bool in_main_loop =
+ qemu_get_current_aio_context() == qemu_get_aio_context();
+ assert(bs->refcnt > 0);
+ if (in_main_loop) {
+ /* In case the recursive bdrv_drain_recurse processes a
+ * block_job_defer_to_main_loop BH and modifies the graph,
+ * let's hold a reference to bs until we are done.
+ *
+ * IOThread doesn't have such a BH, and it is not safe to call
+ * bdrv_unref without BQL, so skip doing it there.
+ */
+ bdrv_ref(bs);
+ }
+ waited |= bdrv_drain_recurse(bs);
+ if (in_main_loop) {
+ bdrv_unref(bs);
+ }
}
return waited;
return;
}
- if (!bs->quiesce_counter++) {
+ if (atomic_fetch_inc(&bs->quiesce_counter) == 0) {
aio_disable_external(bdrv_get_aio_context(bs));
bdrv_parent_drained_begin(bs);
}
void bdrv_drained_end(BlockDriverState *bs)
{
assert(bs->quiesce_counter > 0);
- if (--bs->quiesce_counter > 0) {
+ if (atomic_fetch_dec(&bs->quiesce_counter) > 1) {
return;
}
bool waited = true;
BlockDriverState *bs;
BdrvNextIterator it;
- BlockJob *job = NULL;
GSList *aio_ctxs = NULL, *ctx;
- while ((job = block_job_next(job))) {
- AioContext *aio_context = blk_get_aio_context(job->blk);
-
- aio_context_acquire(aio_context);
- block_job_pause(job);
- aio_context_release(aio_context);
- }
+ block_job_pause_all();
for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
AioContext *aio_context = bdrv_get_aio_context(bs);
{
BlockDriverState *bs;
BdrvNextIterator it;
- BlockJob *job = NULL;
for (bs = bdrv_first(&it); bs; bs = bdrv_next(&it)) {
AioContext *aio_context = bdrv_get_aio_context(bs);
aio_context_release(aio_context);
}
- while ((job = block_job_next(job))) {
- AioContext *aio_context = blk_get_aio_context(job->blk);
-
- aio_context_acquire(aio_context);
- block_job_resume(job);
- aio_context_release(aio_context);
- }
+ block_job_resume_all();
}
void bdrv_drain_all(void)
static void tracked_request_end(BdrvTrackedRequest *req)
{
if (req->serialising) {
- req->bs->serialising_in_flight--;
+ atomic_dec(&req->bs->serialising_in_flight);
}
+ qemu_co_mutex_lock(&req->bs->reqs_lock);
QLIST_REMOVE(req, list);
qemu_co_queue_restart_all(&req->wait_queue);
+ qemu_co_mutex_unlock(&req->bs->reqs_lock);
}
/**
qemu_co_queue_init(&req->wait_queue);
+ qemu_co_mutex_lock(&bs->reqs_lock);
QLIST_INSERT_HEAD(&bs->tracked_requests, req, list);
+ qemu_co_mutex_unlock(&bs->reqs_lock);
}
static void mark_request_serialising(BdrvTrackedRequest *req, uint64_t align)
- overlap_offset;
if (!req->serialising) {
- req->bs->serialising_in_flight++;
+ atomic_inc(&req->bs->serialising_in_flight);
req->serialising = true;
}
void bdrv_wakeup(BlockDriverState *bs)
{
- if (bs->wakeup) {
+ /* The barrier (or an atomic op) is in the caller. */
+ if (atomic_read(&bs->wakeup)) {
aio_bh_schedule_oneshot(qemu_get_aio_context(), dummy_bh_cb, NULL);
}
}
bool retry;
bool waited = false;
- if (!bs->serialising_in_flight) {
+ if (!atomic_read(&bs->serialising_in_flight)) {
return false;
}
do {
retry = false;
+ qemu_co_mutex_lock(&bs->reqs_lock);
QLIST_FOREACH(req, &bs->tracked_requests, list) {
if (req == self || (!req->serialising && !self->serialising)) {
continue;
* (instead of producing a deadlock in the former case). */
if (!req->waiting_for) {
self->waiting_for = req;
- qemu_co_queue_wait(&req->wait_queue, NULL);
+ qemu_co_queue_wait(&req->wait_queue, &bs->reqs_lock);
self->waiting_for = NULL;
retry = true;
waited = true;
}
}
}
+ qemu_co_mutex_unlock(&bs->reqs_lock);
} while (retry);
return waited;
}
int bdrv_pwrite_zeroes(BdrvChild *child, int64_t offset,
- int count, BdrvRequestFlags flags)
+ int bytes, BdrvRequestFlags flags)
{
QEMUIOVector qiov;
struct iovec iov = {
.iov_base = NULL,
- .iov_len = count,
+ .iov_len = bytes,
};
qemu_iovec_init_external(&qiov, &iov, 1);
bdrv_inc_in_flight(bs);
/* Don't do copy-on-read if we read data before write operation */
- if (bs->copy_on_read && !(flags & BDRV_REQ_NO_SERIALISING)) {
+ if (atomic_read(&bs->copy_on_read) && !(flags & BDRV_REQ_NO_SERIALISING)) {
flags |= BDRV_REQ_COPY_ON_READ;
}
#define MAX_WRITE_ZEROES_BOUNCE_BUFFER (32768 << BDRV_SECTOR_BITS)
static int coroutine_fn bdrv_co_do_pwrite_zeroes(BlockDriverState *bs,
- int64_t offset, int count, BdrvRequestFlags flags)
+ int64_t offset, int bytes, BdrvRequestFlags flags)
{
BlockDriver *drv = bs->drv;
QEMUIOVector qiov;
assert(alignment % bs->bl.request_alignment == 0);
head = offset % alignment;
- tail = (offset + count) % alignment;
+ tail = (offset + bytes) % alignment;
max_write_zeroes = QEMU_ALIGN_DOWN(max_write_zeroes, alignment);
assert(max_write_zeroes >= bs->bl.request_alignment);
- while (count > 0 && !ret) {
- int num = count;
+ while (bytes > 0 && !ret) {
+ int num = bytes;
/* Align request. Block drivers can expect the "bulk" of the request
* to be aligned, and that unaligned requests do not cross cluster
/* Make a small request up to the first aligned sector. For
* convenience, limit this request to max_transfer even if
* we don't need to fall back to writes. */
- num = MIN(MIN(count, max_transfer), alignment - head);
+ num = MIN(MIN(bytes, max_transfer), alignment - head);
head = (head + num) % alignment;
assert(num < max_write_zeroes);
} else if (tail && num > alignment) {
}
offset += num;
- count -= num;
+ bytes -= num;
}
fail:
assert(!waited || !req->serialising);
assert(req->overlap_offset <= offset);
assert(offset + bytes <= req->overlap_offset + req->overlap_bytes);
- /* FIXME: Block migration uses the BlockBackend of the guest device at a
- * point when it has not yet taken write permissions. This will be
- * fixed by a future patch, but for now we have to bypass this
- * assertion for block migration to work. */
- // assert(child->perm & BLK_PERM_WRITE);
- /* FIXME: Because of the above, we also cannot guarantee that all format
- * BDS take the BLK_PERM_RESIZE permission on their file BDS, since
- * they are not obligated to do so if they do not have any parent
- * that has taken the permission to write to them. */
- // assert(end_sector <= bs->total_sectors || child->perm & BLK_PERM_RESIZE);
+ assert(child->perm & BLK_PERM_WRITE);
+ assert(end_sector <= bs->total_sectors || child->perm & BLK_PERM_RESIZE);
ret = notifier_with_return_list_notify(&bs->before_write_notifiers, req);
}
bdrv_debug_event(bs, BLKDBG_PWRITEV_DONE);
- ++bs->write_gen;
+ atomic_inc(&bs->write_gen);
bdrv_set_dirty(bs, start_sector, end_sector - start_sector);
- if (bs->wr_highest_offset < offset + bytes) {
- bs->wr_highest_offset = offset + bytes;
- }
+ stat64_max(&bs->wr_highest_offset, offset + bytes);
if (ret >= 0) {
bs->total_sectors = MAX(bs->total_sectors, end_sector);
int ret = 0;
head_padding_bytes = offset & (align - 1);
- tail_padding_bytes = align - ((offset + bytes) & (align - 1));
+ tail_padding_bytes = (align - (offset + bytes)) & (align - 1);
assert(flags & BDRV_REQ_ZERO_WRITE);
}
int coroutine_fn bdrv_co_pwrite_zeroes(BdrvChild *child, int64_t offset,
- int count, BdrvRequestFlags flags)
+ int bytes, BdrvRequestFlags flags)
{
- trace_bdrv_co_pwrite_zeroes(child->bs, offset, count, flags);
+ trace_bdrv_co_pwrite_zeroes(child->bs, offset, bytes, flags);
if (!(child->bs->open_flags & BDRV_O_UNMAP)) {
flags &= ~BDRV_REQ_MAY_UNMAP;
}
- return bdrv_co_pwritev(child, offset, count, NULL,
+ return bdrv_co_pwritev(child, offset, bytes, NULL,
BDRV_REQ_ZERO_WRITE | flags);
}
* Drivers not implementing the functionality are assumed to not support
* backing files, hence all their sectors are reported as allocated.
*
- * If 'sector_num' is beyond the end of the disk image the return value is 0
- * and 'pnum' is set to 0.
+ * If 'sector_num' is beyond the end of the disk image the return value is
+ * BDRV_BLOCK_EOF and 'pnum' is set to 0.
*
* 'pnum' is set to the number of sectors (including and immediately following
* the specified sector) that are known to be in the same
* allocated/unallocated state.
*
* 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes
- * beyond the end of the disk image it will be clamped.
+ * beyond the end of the disk image it will be clamped; if 'pnum' is set to
+ * the end of the image, then the returned value will include BDRV_BLOCK_EOF.
*
* If returned value is positive and BDRV_BLOCK_OFFSET_VALID bit is set, 'file'
* points to the BDS which the sector range is allocated in.
int64_t n;
int64_t ret, ret2;
+ *file = NULL;
total_sectors = bdrv_nb_sectors(bs);
if (total_sectors < 0) {
return total_sectors;
if (sector_num >= total_sectors) {
*pnum = 0;
- return 0;
+ return BDRV_BLOCK_EOF;
}
n = total_sectors - sector_num;
if (!bs->drv->bdrv_co_get_block_status) {
*pnum = nb_sectors;
ret = BDRV_BLOCK_DATA | BDRV_BLOCK_ALLOCATED;
+ if (sector_num + nb_sectors == total_sectors) {
+ ret |= BDRV_BLOCK_EOF;
+ }
if (bs->drv->protocol_name) {
ret |= BDRV_BLOCK_OFFSET_VALID | (sector_num * BDRV_SECTOR_SIZE);
+ *file = bs;
}
return ret;
}
- *file = NULL;
bdrv_inc_in_flight(bs);
ret = bs->drv->bdrv_co_get_block_status(bs, sector_num, nb_sectors, pnum,
file);
}
if (ret & BDRV_BLOCK_RAW) {
- assert(ret & BDRV_BLOCK_OFFSET_VALID);
- ret = bdrv_get_block_status(*file, ret >> BDRV_SECTOR_BITS,
- *pnum, pnum, file);
+ assert(ret & BDRV_BLOCK_OFFSET_VALID && *file);
+ ret = bdrv_co_get_block_status(*file, ret >> BDRV_SECTOR_BITS,
+ *pnum, pnum, file);
goto out;
}
/* Ignore errors. This is just providing extra information, it
* is useful but not necessary.
*/
- if (!file_pnum) {
- /* !file_pnum indicates an offset at or beyond the EOF; it is
- * perfectly valid for the format block driver to point to such
- * offsets, so catch it and mark everything as zero */
+ if (ret2 & BDRV_BLOCK_EOF &&
+ (!file_pnum || ret2 & BDRV_BLOCK_ZERO)) {
+ /*
+ * It is valid for the format block driver to read
+ * beyond the end of the underlying file's current
+ * size; such areas read as zero.
+ */
ret |= BDRV_BLOCK_ZERO;
} else {
/* Limit request to the range reported by the protocol driver */
out:
bdrv_dec_in_flight(bs);
+ if (ret >= 0 && sector_num + *pnum == total_sectors) {
+ ret |= BDRV_BLOCK_EOF;
+ }
return ret;
}
{
BlockDriverState *p;
int64_t ret = 0;
+ bool first = true;
assert(bs != base);
for (p = bs; p != base; p = backing_bs(p)) {
ret = bdrv_co_get_block_status(p, sector_num, nb_sectors, pnum, file);
- if (ret < 0 || ret & BDRV_BLOCK_ALLOCATED) {
+ if (ret < 0) {
+ break;
+ }
+ if (ret & BDRV_BLOCK_ZERO && ret & BDRV_BLOCK_EOF && !first) {
+ /*
+ * 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.
+ */
+ *pnum = nb_sectors;
+ }
+ if (ret & (BDRV_BLOCK_ZERO | BDRV_BLOCK_DATA)) {
break;
}
/* [sector_num, pnum] unallocated on this layer, which could be only
* the first part of [sector_num, nb_sectors]. */
nb_sectors = MIN(nb_sectors, *pnum);
+ first = false;
}
return ret;
}
bool is_read)
{
BlockDriver *drv = bs->drv;
+ int ret = -ENOTSUP;
+
+ bdrv_inc_in_flight(bs);
if (!drv) {
- return -ENOMEDIUM;
+ ret = -ENOMEDIUM;
} else if (drv->bdrv_load_vmstate) {
- return is_read ? drv->bdrv_load_vmstate(bs, qiov, pos)
- : drv->bdrv_save_vmstate(bs, qiov, pos);
+ if (is_read) {
+ ret = drv->bdrv_load_vmstate(bs, qiov, pos);
+ } else {
+ ret = drv->bdrv_save_vmstate(bs, qiov, pos);
+ }
} else if (bs->file) {
- return bdrv_co_rw_vmstate(bs->file->bs, qiov, pos, is_read);
+ ret = bdrv_co_rw_vmstate(bs->file->bs, qiov, pos, is_read);
}
- return -ENOTSUP;
+ bdrv_dec_in_flight(bs);
+ return ret;
}
static void coroutine_fn bdrv_co_rw_vmstate_entry(void *opaque)
Coroutine *co = qemu_coroutine_create(bdrv_co_rw_vmstate_entry, &data);
bdrv_coroutine_enter(bs, co);
- while (data.ret == -EINPROGRESS) {
- aio_poll(bdrv_get_aio_context(bs), true);
- }
+ BDRV_POLL_WHILE(bs, data.ret == -EINPROGRESS);
return data.ret;
}
}
/**************************************************************/
/* async I/Os */
-BlockAIOCB *bdrv_aio_readv(BdrvChild *child, int64_t sector_num,
- QEMUIOVector *qiov, int nb_sectors,
- BlockCompletionFunc *cb, void *opaque)
-{
- trace_bdrv_aio_readv(child->bs, sector_num, nb_sectors, opaque);
-
- assert(nb_sectors << BDRV_SECTOR_BITS == qiov->size);
- return bdrv_co_aio_prw_vector(child, sector_num << BDRV_SECTOR_BITS, qiov,
- 0, cb, opaque, false);
-}
-
-BlockAIOCB *bdrv_aio_writev(BdrvChild *child, int64_t sector_num,
- QEMUIOVector *qiov, int nb_sectors,
- BlockCompletionFunc *cb, void *opaque)
-{
- trace_bdrv_aio_writev(child->bs, sector_num, nb_sectors, opaque);
-
- assert(nb_sectors << BDRV_SECTOR_BITS == qiov->size);
- return bdrv_co_aio_prw_vector(child, sector_num << BDRV_SECTOR_BITS, qiov,
- 0, cb, opaque, true);
-}
-
void bdrv_aio_cancel(BlockAIOCB *acb)
{
qemu_aio_ref(acb);
}
}
-/**************************************************************/
-/* async block device emulation */
-
-typedef struct BlockRequest {
- union {
- /* Used during read, write, trim */
- struct {
- int64_t offset;
- int bytes;
- int flags;
- QEMUIOVector *qiov;
- };
- /* Used during ioctl */
- struct {
- int req;
- void *buf;
- };
- };
- BlockCompletionFunc *cb;
- void *opaque;
-
- int error;
-} BlockRequest;
-
-typedef struct BlockAIOCBCoroutine {
- BlockAIOCB common;
- BdrvChild *child;
- BlockRequest req;
- bool is_write;
- bool need_bh;
- bool *done;
-} BlockAIOCBCoroutine;
-
-static const AIOCBInfo bdrv_em_co_aiocb_info = {
- .aiocb_size = sizeof(BlockAIOCBCoroutine),
-};
-
-static void bdrv_co_complete(BlockAIOCBCoroutine *acb)
-{
- if (!acb->need_bh) {
- bdrv_dec_in_flight(acb->common.bs);
- acb->common.cb(acb->common.opaque, acb->req.error);
- qemu_aio_unref(acb);
- }
-}
-
-static void bdrv_co_em_bh(void *opaque)
-{
- BlockAIOCBCoroutine *acb = opaque;
-
- assert(!acb->need_bh);
- bdrv_co_complete(acb);
-}
-
-static void bdrv_co_maybe_schedule_bh(BlockAIOCBCoroutine *acb)
-{
- acb->need_bh = false;
- if (acb->req.error != -EINPROGRESS) {
- BlockDriverState *bs = acb->common.bs;
-
- aio_bh_schedule_oneshot(bdrv_get_aio_context(bs), bdrv_co_em_bh, acb);
- }
-}
-
-/* Invoke bdrv_co_do_readv/bdrv_co_do_writev */
-static void coroutine_fn bdrv_co_do_rw(void *opaque)
-{
- BlockAIOCBCoroutine *acb = opaque;
-
- if (!acb->is_write) {
- acb->req.error = bdrv_co_preadv(acb->child, acb->req.offset,
- acb->req.qiov->size, acb->req.qiov, acb->req.flags);
- } else {
- acb->req.error = bdrv_co_pwritev(acb->child, acb->req.offset,
- acb->req.qiov->size, acb->req.qiov, acb->req.flags);
- }
-
- bdrv_co_complete(acb);
-}
-
-static BlockAIOCB *bdrv_co_aio_prw_vector(BdrvChild *child,
- int64_t offset,
- QEMUIOVector *qiov,
- BdrvRequestFlags flags,
- BlockCompletionFunc *cb,
- void *opaque,
- bool is_write)
-{
- Coroutine *co;
- BlockAIOCBCoroutine *acb;
-
- /* Matched by bdrv_co_complete's bdrv_dec_in_flight. */
- bdrv_inc_in_flight(child->bs);
-
- acb = qemu_aio_get(&bdrv_em_co_aiocb_info, child->bs, cb, opaque);
- acb->child = child;
- acb->need_bh = true;
- acb->req.error = -EINPROGRESS;
- acb->req.offset = offset;
- acb->req.qiov = qiov;
- acb->req.flags = flags;
- acb->is_write = is_write;
-
- co = qemu_coroutine_create(bdrv_co_do_rw, acb);
- bdrv_coroutine_enter(child->bs, co);
-
- bdrv_co_maybe_schedule_bh(acb);
- return &acb->common;
-}
-
-static void coroutine_fn bdrv_aio_flush_co_entry(void *opaque)
-{
- BlockAIOCBCoroutine *acb = opaque;
- BlockDriverState *bs = acb->common.bs;
-
- acb->req.error = bdrv_co_flush(bs);
- bdrv_co_complete(acb);
-}
-
-BlockAIOCB *bdrv_aio_flush(BlockDriverState *bs,
- BlockCompletionFunc *cb, void *opaque)
-{
- trace_bdrv_aio_flush(bs, opaque);
-
- Coroutine *co;
- BlockAIOCBCoroutine *acb;
-
- /* Matched by bdrv_co_complete's bdrv_dec_in_flight. */
- bdrv_inc_in_flight(bs);
-
- acb = qemu_aio_get(&bdrv_em_co_aiocb_info, bs, cb, opaque);
- acb->need_bh = true;
- acb->req.error = -EINPROGRESS;
-
- co = qemu_coroutine_create(bdrv_aio_flush_co_entry, acb);
- bdrv_coroutine_enter(bs, co);
-
- bdrv_co_maybe_schedule_bh(acb);
- return &acb->common;
-}
-
/**************************************************************/
/* Coroutine block device emulation */
bdrv_inc_in_flight(bs);
- if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs) ||
+ if (!bdrv_is_inserted(bs) || bdrv_is_read_only(bs) ||
bdrv_is_sg(bs)) {
goto early_exit;
}
- current_gen = bs->write_gen;
+ qemu_co_mutex_lock(&bs->reqs_lock);
+ current_gen = atomic_read(&bs->write_gen);
/* Wait until any previous flushes are completed */
while (bs->active_flush_req) {
- qemu_co_queue_wait(&bs->flush_queue, NULL);
+ qemu_co_queue_wait(&bs->flush_queue, &bs->reqs_lock);
}
+ /* Flushes reach this point in nondecreasing current_gen order. */
bs->active_flush_req = true;
+ qemu_co_mutex_unlock(&bs->reqs_lock);
/* Write back all layers by calling one driver function */
if (bs->drv->bdrv_co_flush) {
if (ret == 0) {
bs->flushed_gen = current_gen;
}
+
+ qemu_co_mutex_lock(&bs->reqs_lock);
bs->active_flush_req = false;
/* Return value is ignored - it's ok if wait queue is empty */
qemu_co_queue_next(&bs->flush_queue);
+ qemu_co_mutex_unlock(&bs->reqs_lock);
early_exit:
bdrv_dec_in_flight(bs);
typedef struct DiscardCo {
BlockDriverState *bs;
int64_t offset;
- int count;
+ int bytes;
int ret;
} DiscardCo;
static void coroutine_fn bdrv_pdiscard_co_entry(void *opaque)
{
DiscardCo *rwco = opaque;
- rwco->ret = bdrv_co_pdiscard(rwco->bs, rwco->offset, rwco->count);
+ rwco->ret = bdrv_co_pdiscard(rwco->bs, rwco->offset, rwco->bytes);
}
int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset,
- int count)
+ int bytes)
{
BdrvTrackedRequest req;
int max_pdiscard, ret;
return -ENOMEDIUM;
}
- ret = bdrv_check_byte_request(bs, offset, count);
+ ret = bdrv_check_byte_request(bs, offset, bytes);
if (ret < 0) {
return ret;
} else if (bs->read_only) {
align = MAX(bs->bl.pdiscard_alignment, bs->bl.request_alignment);
assert(align % bs->bl.request_alignment == 0);
head = offset % align;
- tail = (offset + count) % align;
+ tail = (offset + bytes) % align;
bdrv_inc_in_flight(bs);
- tracked_request_begin(&req, bs, offset, count, BDRV_TRACKED_DISCARD);
+ tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_DISCARD);
ret = notifier_with_return_list_notify(&bs->before_write_notifiers, &req);
if (ret < 0) {
align);
assert(max_pdiscard >= bs->bl.request_alignment);
- while (count > 0) {
+ while (bytes > 0) {
int ret;
- int num = count;
+ int num = bytes;
if (head) {
/* Make small requests to get to alignment boundaries. */
- num = MIN(count, align - head);
+ num = MIN(bytes, align - head);
if (!QEMU_IS_ALIGNED(num, bs->bl.request_alignment)) {
num %= bs->bl.request_alignment;
}
}
offset += num;
- count -= num;
+ bytes -= num;
}
ret = 0;
out:
- ++bs->write_gen;
+ atomic_inc(&bs->write_gen);
bdrv_set_dirty(bs, req.offset >> BDRV_SECTOR_BITS,
req.bytes >> BDRV_SECTOR_BITS);
tracked_request_end(&req);
return ret;
}
-int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int count)
+int bdrv_pdiscard(BlockDriverState *bs, int64_t offset, int bytes)
{
Coroutine *co;
DiscardCo rwco = {
.bs = bs,
.offset = offset,
- .count = count,
+ .bytes = bytes,
.ret = NOT_DONE,
};
bdrv_io_plug(child->bs);
}
- if (bs->io_plugged++ == 0) {
+ if (atomic_fetch_inc(&bs->io_plugged) == 0) {
BlockDriver *drv = bs->drv;
if (drv && drv->bdrv_io_plug) {
drv->bdrv_io_plug(bs);
BdrvChild *child;
assert(bs->io_plugged);
- if (--bs->io_plugged == 0) {
+ if (atomic_fetch_dec(&bs->io_plugged) == 1) {
BlockDriver *drv = bs->drv;
if (drv && drv->bdrv_io_unplug) {
drv->bdrv_io_unplug(bs);
projects / mirror_qemu.git / blobdiff