diff options
Diffstat (limited to 'block')
| -rw-r--r-- | block/nbd-client.c | 30 |
1 files changed, 9 insertions, 21 deletions
diff --git a/block/nbd-client.c b/block/nbd-client.c index 09d955bc4d..87d19c7253 100644 --- a/block/nbd-client.c +++ b/block/nbd-client.c @@ -119,6 +119,10 @@ static int nbd_co_send_request(BlockDriverState *bs, int rc, ret, i; qemu_co_mutex_lock(&s->send_mutex); + while (s->in_flight == MAX_NBD_REQUESTS) { + qemu_co_queue_wait(&s->free_sema, &s->send_mutex); + } + s->in_flight++; for (i = 0; i < MAX_NBD_REQUESTS; i++) { if (s->recv_coroutine[i] == NULL) { @@ -181,20 +185,6 @@ static void nbd_co_receive_reply(NBDClientSession *s, } } -static void nbd_coroutine_start(NBDClientSession *s, - NBDRequest *request) -{ - /* Poor man semaphore. The free_sema is locked when no other request - * can be accepted, and unlocked after receiving one reply. */ - if (s->in_flight == MAX_NBD_REQUESTS) { - qemu_co_queue_wait(&s->free_sema, NULL); - assert(s->in_flight < MAX_NBD_REQUESTS); - } - s->in_flight++; - - /* s->recv_coroutine[i] is set as soon as we get the send_lock. */ -} - static void nbd_coroutine_end(BlockDriverState *bs, NBDRequest *request) { @@ -202,13 +192,16 @@ static void nbd_coroutine_end(BlockDriverState *bs, int i = HANDLE_TO_INDEX(s, request->handle); s->recv_coroutine[i] = NULL; - s->in_flight--; - qemu_co_queue_next(&s->free_sema); /* Kick the read_reply_co to get the next reply. */ if (s->read_reply_co) { aio_co_wake(s->read_reply_co); } + + qemu_co_mutex_lock(&s->send_mutex); + s->in_flight--; + qemu_co_queue_next(&s->free_sema); + qemu_co_mutex_unlock(&s->send_mutex); } int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset, @@ -226,7 +219,6 @@ int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset, assert(bytes <= NBD_MAX_BUFFER_SIZE); assert(!flags); - nbd_coroutine_start(client, &request); ret = nbd_co_send_request(bs, &request, NULL); if (ret < 0) { reply.error = -ret; @@ -256,7 +248,6 @@ int nbd_client_co_pwritev(BlockDriverState *bs, uint64_t offset, assert(bytes <= NBD_MAX_BUFFER_SIZE); - nbd_coroutine_start(client, &request); ret = nbd_co_send_request(bs, &request, qiov); if (ret < 0) { reply.error = -ret; @@ -291,7 +282,6 @@ int nbd_client_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, request.flags |= NBD_CMD_FLAG_NO_HOLE; } - nbd_coroutine_start(client, &request); ret = nbd_co_send_request(bs, &request, NULL); if (ret < 0) { reply.error = -ret; @@ -316,7 +306,6 @@ int nbd_client_co_flush(BlockDriverState *bs) request.from = 0; request.len = 0; - nbd_coroutine_start(client, &request); ret = nbd_co_send_request(bs, &request, NULL); if (ret < 0) { reply.error = -ret; @@ -342,7 +331,6 @@ int nbd_client_co_pdiscard(BlockDriverState *bs, int64_t offset, int count) return 0; } - nbd_coroutine_start(client, &request); ret = nbd_co_send_request(bs, &request, NULL); if (ret < 0) { reply.error = -ret; |