block: Add bdrv_aio_cancel_async

This is the async version of bdrv_aio_cancel, which doesn't block the
caller. It guarantees that the cb is called either before returning or
some time later.

bdrv_aio_cancel can base on bdrv_aio_cancel_async, later we can convert
all .io_cancel implementations to .io_cancel_async, and the aio_poll is
the common logic. In the end, .io_cancel can be dropped.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Fam Zheng 2014-09-11 13:41:09 +08:00 committed by Stefan Hajnoczi
parent f197fe2b2c
commit 02c50efe08
3 changed files with 29 additions and 1 deletions

View file

@ -27,6 +27,8 @@ typedef void BlockDriverCompletionFunc(void *opaque, int ret);
typedef struct AIOCBInfo {
void (*cancel)(BlockDriverAIOCB *acb);
void (*cancel_async)(BlockDriverAIOCB *acb);
AioContext *(*get_aio_context)(BlockDriverAIOCB *acb);
size_t aiocb_size;
} AIOCBInfo;

View file

@ -337,6 +337,7 @@ BlockDriverAIOCB *bdrv_aio_discard(BlockDriverState *bs,
int64_t sector_num, int nb_sectors,
BlockDriverCompletionFunc *cb, void *opaque);
void bdrv_aio_cancel(BlockDriverAIOCB *acb);
void bdrv_aio_cancel_async(BlockDriverAIOCB *acb);
typedef struct BlockRequest {
/* Fields to be filled by multiwrite caller */