Reviewed-by: Stefan Hajnoczi <stefa...@redhat.com>
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
---
block.c | 1 +
block/io.c | 16 ++++++++++++++--
include/block/block_int.h | 14 +++++++++-----
3 files changed, 24 insertions(+), 7 deletions(-)
diff --git a/block.c b/block.c
index 45a77f5..d297188 100644
--- a/block.c
+++ b/block.c
@@ -280,6 +280,7 @@ BlockDriverState *bdrv_new(void)
QLIST_INIT(&bs->op_blockers[i]);
}
notifier_with_return_list_init(&bs->before_write_notifiers);
+ qemu_co_mutex_init(&bs->reqs_lock);
bs->refcnt = 1;
bs->aio_context = qemu_get_aio_context();
diff --git a/block/io.c b/block/io.c
index 8021b5b..caca63a 100644
--- a/block/io.c
+++ b/block/io.c
@@ -391,8 +391,10 @@ static void tracked_request_end(BdrvTrackedRequest *req)
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);
}
/**
@@ -417,7 +419,9 @@ static void tracked_request_begin(BdrvTrackedRequest *req,
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)
@@ -539,6 +543,7 @@ static bool coroutine_fn
wait_serialising_requests(BdrvTrackedRequest *self)
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;
@@ -557,7 +562,7 @@ static bool coroutine_fn
wait_serialising_requests(BdrvTrackedRequest *self)
* (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;
@@ -565,6 +570,7 @@ static bool coroutine_fn
wait_serialising_requests(BdrvTrackedRequest *self)
}
}
}
+ qemu_co_mutex_unlock(&bs->reqs_lock);
} while (retry);
return waited;
@@ -2304,14 +2310,17 @@ int coroutine_fn bdrv_co_flush(BlockDriverState *bs)
goto early_exit;
}
+ 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) {
@@ -2383,9 +2392,12 @@ out:
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);
diff --git a/include/block/block_int.h b/include/block/block_int.h
index 74d6e62..4b2c594 100644
--- a/include/block/block_int.h
+++ b/include/block/block_int.h
@@ -609,11 +609,6 @@ struct BlockDriverState {
uint64_t write_threshold_offset;
NotifierWithReturn write_threshold_notifier;
- QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
- CoQueue flush_queue; /* Serializing flush queue */
- bool active_flush_req; /* Flush request in flight? */
- unsigned int flushed_gen; /* Flushed write generation */
-
QLIST_HEAD(, BdrvDirtyBitmap) dirty_bitmaps;
/* Offset after the highest byte written to */
@@ -647,6 +642,15 @@ struct BlockDriverState {
/* Accessed with atomic ops. */
int quiesce_counter;
unsigned int write_gen; /* Current data generation */
+
+ /* Protected by reqs_lock. */
+ CoMutex reqs_lock;
+ QLIST_HEAD(, BdrvTrackedRequest) tracked_requests;
+ CoQueue flush_queue; /* Serializing flush queue */
+ bool active_flush_req; /* Flush request in flight? */
+
+ /* Only read/written by whoever has set active_flush_req to true. */
+ unsigned int flushed_gen; /* Flushed write generation */
};
struct BlockBackendRootState {
--
1.8.3.1
