From 23b0d9fb1dd39d85fc2e0cabba5cbe005126e7b5 Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Fri, 3 Jun 2016 16:45:44 +0200 Subject: block: Don't enforce 512 byte minimum alignment If block drivers say that they can do an alignment < 512 bytes, let's just suppose they mean it. raw-posix used to be an offender with respect to this, but it can actually deal with byte-aligned requests now. The default is still 512 bytes for any drivers that only implement sector-based interfaces, but it is 1 now for drivers that implement .bdrv_co_preadv. Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake Reviewed-by: Stefan Hajnoczi --- block/io.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) (limited to 'block') diff --git a/block/io.c b/block/io.c index b261cc6..b3ff9be 100644 --- a/block/io.c +++ b/block/io.c @@ -1052,8 +1052,7 @@ int coroutine_fn bdrv_co_preadv(BlockDriverState *bs, BlockDriver *drv = bs->drv; BdrvTrackedRequest req; - /* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */ - uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); + uint64_t align = bs->request_alignment; uint8_t *head_buf = NULL; uint8_t *tail_buf = NULL; QEMUIOVector local_qiov; @@ -1305,7 +1304,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, uint8_t *buf = NULL; QEMUIOVector local_qiov; struct iovec iov; - uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); + uint64_t align = bs->request_alignment; unsigned int head_padding_bytes, tail_padding_bytes; int ret = 0; @@ -1392,8 +1391,7 @@ int coroutine_fn bdrv_co_pwritev(BlockDriverState *bs, BdrvRequestFlags flags) { BdrvTrackedRequest req; - /* TODO Lift BDRV_SECTOR_SIZE restriction in BlockDriver interface */ - uint64_t align = MAX(BDRV_SECTOR_SIZE, bs->request_alignment); + uint64_t align = bs->request_alignment; uint8_t *head_buf = NULL; uint8_t *tail_buf = NULL; QEMUIOVector local_qiov; -- cgit v1.1