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Diffstat (limited to 'block/io.c')
-rw-r--r--block/io.c150
1 files changed, 130 insertions, 20 deletions
diff --git a/block/io.c b/block/io.c
index 8dcad3b3fe..adc1eabef0 100644
--- a/block/io.c
+++ b/block/io.c
@@ -237,8 +237,21 @@ bool bdrv_requests_pending(BlockDriverState *bs)
return false;
}
+static void bdrv_drain_recurse(BlockDriverState *bs)
+{
+ BdrvChild *child;
+
+ if (bs->drv && bs->drv->bdrv_drain) {
+ bs->drv->bdrv_drain(bs);
+ }
+ QLIST_FOREACH(child, &bs->children, next) {
+ bdrv_drain_recurse(child->bs);
+ }
+}
+
/*
- * Wait for pending requests to complete on a single BlockDriverState subtree
+ * Wait for pending requests to complete on a single BlockDriverState subtree,
+ * and suspend block driver's internal I/O until next request arrives.
*
* Note that unlike bdrv_drain_all(), the caller must hold the BlockDriverState
* AioContext.
@@ -251,6 +264,7 @@ void bdrv_drain(BlockDriverState *bs)
{
bool busy = true;
+ bdrv_drain_recurse(bs);
while (busy) {
/* Keep iterating */
bdrv_flush_io_queue(bs);
@@ -348,13 +362,14 @@ static void tracked_request_end(BdrvTrackedRequest *req)
static void tracked_request_begin(BdrvTrackedRequest *req,
BlockDriverState *bs,
int64_t offset,
- unsigned int bytes, bool is_write)
+ unsigned int bytes,
+ enum BdrvTrackedRequestType type)
{
*req = (BdrvTrackedRequest){
.bs = bs,
.offset = offset,
.bytes = bytes,
- .is_write = is_write,
+ .type = type,
.co = qemu_coroutine_self(),
.serialising = false,
.overlap_offset = offset,
@@ -971,7 +986,7 @@ static int coroutine_fn bdrv_co_do_preadv(BlockDriverState *bs,
bytes = ROUND_UP(bytes, align);
}
- tracked_request_begin(&req, bs, offset, bytes, false);
+ tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_READ);
ret = bdrv_aligned_preadv(bs, &req, offset, bytes, align,
use_local_qiov ? &local_qiov : qiov,
flags);
@@ -1292,7 +1307,7 @@ static int coroutine_fn bdrv_co_do_pwritev(BlockDriverState *bs,
* Pad qiov with the read parts and be sure to have a tracked request not
* only for bdrv_aligned_pwritev, but also for the reads of the RMW cycle.
*/
- tracked_request_begin(&req, bs, offset, bytes, true);
+ tracked_request_begin(&req, bs, offset, bytes, BDRV_TRACKED_WRITE);
if (!qiov) {
ret = bdrv_co_do_zero_pwritev(bs, offset, bytes, flags, &req);
@@ -2317,18 +2332,20 @@ static void coroutine_fn bdrv_flush_co_entry(void *opaque)
int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
{
int ret;
+ BdrvTrackedRequest req;
if (!bs || !bdrv_is_inserted(bs) || bdrv_is_read_only(bs) ||
bdrv_is_sg(bs)) {
return 0;
}
+ tracked_request_begin(&req, bs, 0, 0, BDRV_TRACKED_FLUSH);
/* Write back cached data to the OS even with cache=unsafe */
BLKDBG_EVENT(bs->file, BLKDBG_FLUSH_TO_OS);
if (bs->drv->bdrv_co_flush_to_os) {
ret = bs->drv->bdrv_co_flush_to_os(bs);
if (ret < 0) {
- return ret;
+ goto out;
}
}
@@ -2368,14 +2385,17 @@ int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
ret = 0;
}
if (ret < 0) {
- return ret;
+ goto out;
}
/* Now flush the underlying protocol. It will also have BDRV_O_NO_FLUSH
* in the case of cache=unsafe, so there are no useless flushes.
*/
flush_parent:
- return bs->file ? bdrv_co_flush(bs->file->bs) : 0;
+ ret = bs->file ? bdrv_co_flush(bs->file->bs) : 0;
+out:
+ tracked_request_end(&req);
+ return ret;
}
int bdrv_flush(BlockDriverState *bs)
@@ -2418,6 +2438,7 @@ static void coroutine_fn bdrv_discard_co_entry(void *opaque)
int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
int nb_sectors)
{
+ BdrvTrackedRequest req;
int max_discard, ret;
if (!bs->drv) {
@@ -2440,6 +2461,8 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
return 0;
}
+ tracked_request_begin(&req, bs, sector_num, nb_sectors,
+ BDRV_TRACKED_DISCARD);
bdrv_set_dirty(bs, sector_num, nb_sectors);
max_discard = MIN_NON_ZERO(bs->bl.max_discard, BDRV_REQUEST_MAX_SECTORS);
@@ -2473,20 +2496,24 @@ int coroutine_fn bdrv_co_discard(BlockDriverState *bs, int64_t sector_num,
acb = bs->drv->bdrv_aio_discard(bs, sector_num, nb_sectors,
bdrv_co_io_em_complete, &co);
if (acb == NULL) {
- return -EIO;
+ ret = -EIO;
+ goto out;
} else {
qemu_coroutine_yield();
ret = co.ret;
}
}
if (ret && ret != -ENOTSUP) {
- return ret;
+ goto out;
}
sector_num += num;
nb_sectors -= num;
}
- return 0;
+ ret = 0;
+out:
+ tracked_request_end(&req);
+ return ret;
}
int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)
@@ -2515,26 +2542,109 @@ int bdrv_discard(BlockDriverState *bs, int64_t sector_num, int nb_sectors)
return rwco.ret;
}
-/* needed for generic scsi interface */
+typedef struct {
+ CoroutineIOCompletion *co;
+ QEMUBH *bh;
+} BdrvIoctlCompletionData;
-int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
+static void bdrv_ioctl_bh_cb(void *opaque)
+{
+ BdrvIoctlCompletionData *data = opaque;
+
+ bdrv_co_io_em_complete(data->co, -ENOTSUP);
+ qemu_bh_delete(data->bh);
+}
+
+static int bdrv_co_do_ioctl(BlockDriverState *bs, int req, void *buf)
{
BlockDriver *drv = bs->drv;
+ BdrvTrackedRequest tracked_req;
+ CoroutineIOCompletion co = {
+ .coroutine = qemu_coroutine_self(),
+ };
+ BlockAIOCB *acb;
- if (drv && drv->bdrv_ioctl)
- return drv->bdrv_ioctl(bs, req, buf);
- return -ENOTSUP;
+ tracked_request_begin(&tracked_req, bs, 0, 0, BDRV_TRACKED_IOCTL);
+ if (!drv || !drv->bdrv_aio_ioctl) {
+ co.ret = -ENOTSUP;
+ goto out;
+ }
+
+ acb = drv->bdrv_aio_ioctl(bs, req, buf, bdrv_co_io_em_complete, &co);
+ if (!acb) {
+ BdrvIoctlCompletionData *data = g_new(BdrvIoctlCompletionData, 1);
+ data->bh = aio_bh_new(bdrv_get_aio_context(bs),
+ bdrv_ioctl_bh_cb, data);
+ data->co = &co;
+ qemu_bh_schedule(data->bh);
+ }
+ qemu_coroutine_yield();
+out:
+ tracked_request_end(&tracked_req);
+ return co.ret;
+}
+
+typedef struct {
+ BlockDriverState *bs;
+ int req;
+ void *buf;
+ int ret;
+} BdrvIoctlCoData;
+
+static void coroutine_fn bdrv_co_ioctl_entry(void *opaque)
+{
+ BdrvIoctlCoData *data = opaque;
+ data->ret = bdrv_co_do_ioctl(data->bs, data->req, data->buf);
+}
+
+/* needed for generic scsi interface */
+int bdrv_ioctl(BlockDriverState *bs, unsigned long int req, void *buf)
+{
+ BdrvIoctlCoData data = {
+ .bs = bs,
+ .req = req,
+ .buf = buf,
+ .ret = -EINPROGRESS,
+ };
+
+ if (qemu_in_coroutine()) {
+ /* Fast-path if already in coroutine context */
+ bdrv_co_ioctl_entry(&data);
+ } else {
+ Coroutine *co = qemu_coroutine_create(bdrv_co_ioctl_entry);
+ qemu_coroutine_enter(co, &data);
+ }
+ while (data.ret == -EINPROGRESS) {
+ aio_poll(bdrv_get_aio_context(bs), true);
+ }
+ return data.ret;
+}
+
+static void coroutine_fn bdrv_co_aio_ioctl_entry(void *opaque)
+{
+ BlockAIOCBCoroutine *acb = opaque;
+ acb->req.error = bdrv_co_do_ioctl(acb->common.bs,
+ acb->req.req, acb->req.buf);
+ bdrv_co_complete(acb);
}
BlockAIOCB *bdrv_aio_ioctl(BlockDriverState *bs,
unsigned long int req, void *buf,
BlockCompletionFunc *cb, void *opaque)
{
- BlockDriver *drv = bs->drv;
+ BlockAIOCBCoroutine *acb = qemu_aio_get(&bdrv_em_co_aiocb_info,
+ bs, cb, opaque);
+ Coroutine *co;
- if (drv && drv->bdrv_aio_ioctl)
- return drv->bdrv_aio_ioctl(bs, req, buf, cb, opaque);
- return NULL;
+ acb->need_bh = true;
+ acb->req.error = -EINPROGRESS;
+ acb->req.req = req;
+ acb->req.buf = buf;
+ co = qemu_coroutine_create(bdrv_co_aio_ioctl_entry);
+ qemu_coroutine_enter(co, acb);
+
+ bdrv_co_maybe_schedule_bh(acb);
+ return &acb->common;
}
void *qemu_blockalign(BlockDriverState *bs, size_t size)