From e31f6864a6d6fa072a5d02e7679d0db6d0c22311 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Tue, 24 Apr 2018 14:25:01 -0500 Subject: block: Support byte-based aio callbacks We are gradually moving away from sector-based interfaces, towards byte-based. Add new sector-based aio callbacks for read and write, to match the fact that bdrv_aio_pdiscard is already byte-based. Ideally, drivers should be converted to use coroutine callbacks rather than aio; but that is not quite as trivial (and if we were to do that conversion, the null-aio driver would disappear), so for the short term, converting the signature but keeping things with aio is easier. However, we CAN declare that a driver that uses the byte-based aio interfaces now defaults to byte-based operations, and must explicitly provide a refresh_limits override to stick with larger alignments (making the alignment issues more obvious directly in the drivers touched in the next few patches). Once all drivers are converted, the sector-based aio callbacks will be removed; in the meantime, a FIXME comment is added due to a slight inefficiency that will be touched up as part of that later cleanup. Simplify some instances of 'bs->drv' into 'drv' while touching this, since the local variable already exists to reduce typing. Signed-off-by: Eric Blake Signed-off-by: Kevin Wolf --- include/block/block_int.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/block') diff --git a/include/block/block_int.h b/include/block/block_int.h index c4dd1d4bb8..e772e3502b 100644 --- a/include/block/block_int.h +++ b/include/block/block_int.h @@ -144,9 +144,15 @@ struct BlockDriver { BlockAIOCB *(*bdrv_aio_readv)(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockCompletionFunc *cb, void *opaque); + BlockAIOCB *(*bdrv_aio_preadv)(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, + BlockCompletionFunc *cb, void *opaque); BlockAIOCB *(*bdrv_aio_writev)(BlockDriverState *bs, int64_t sector_num, QEMUIOVector *qiov, int nb_sectors, BlockCompletionFunc *cb, void *opaque); + BlockAIOCB *(*bdrv_aio_pwritev)(BlockDriverState *bs, + uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags, + BlockCompletionFunc *cb, void *opaque); BlockAIOCB *(*bdrv_aio_flush)(BlockDriverState *bs, BlockCompletionFunc *cb, void *opaque); BlockAIOCB *(*bdrv_aio_pdiscard)(BlockDriverState *bs, -- cgit v1.2.3-55-g7522