From cff86b38aca34c9cc5c6f8846cc1c5b3d181c376 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Thu, 23 Jun 2016 16:37:05 -0600 Subject: block: Tighter assertions on bdrv_aligned_pwritev() For symmetry with bdrv_aligned_preadv(), assert that the caller really has aligned things properly. This requires adding an align parameter, which is used now only in the new asserts, but will come in handy in a later patch that adds auto-fragmentation to the max transfer size, since that value need not always be a multiple of the alignment, and therefore must be rounded down. Signed-off-by: Eric Blake Reviewed-by: Kevin Wolf Reviewed-by: Fam Zheng Reviewed-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- block/io.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'block') diff --git a/block/io.c b/block/io.c index 7cf3645ade..b95e856cf9 100644 --- a/block/io.c +++ b/block/io.c @@ -1254,7 +1254,7 @@ fail: */ static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, BdrvTrackedRequest *req, int64_t offset, unsigned int bytes, - QEMUIOVector *qiov, int flags) + int64_t align, QEMUIOVector *qiov, int flags) { BlockDriver *drv = bs->drv; bool waited; @@ -1263,6 +1263,9 @@ static int coroutine_fn bdrv_aligned_pwritev(BlockDriverState *bs, int64_t start_sector = offset >> BDRV_SECTOR_BITS; int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE); + assert(is_power_of_2(align)); + assert((offset & (align - 1)) == 0); + assert((bytes & (align - 1)) == 0); assert(!qiov || bytes == qiov->size); assert((bs->open_flags & BDRV_O_NO_IO) == 0); assert(!(flags & ~BDRV_REQ_MASK)); @@ -1349,7 +1352,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, memset(buf + head_padding_bytes, 0, zero_bytes); ret = bdrv_aligned_pwritev(bs, req, offset & ~(align - 1), align, - &local_qiov, + align, &local_qiov, flags & ~BDRV_REQ_ZERO_WRITE); if (ret < 0) { goto fail; @@ -1362,7 +1365,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, if (bytes >= align) { /* Write the aligned part in the middle. */ uint64_t aligned_bytes = bytes & ~(align - 1); - ret = bdrv_aligned_pwritev(bs, req, offset, aligned_bytes, + ret = bdrv_aligned_pwritev(bs, req, offset, aligned_bytes, align, NULL, flags); if (ret < 0) { goto fail; @@ -1386,7 +1389,7 @@ static int coroutine_fn bdrv_co_do_zero_pwritev(BlockDriverState *bs, bdrv_debug_event(bs, BLKDBG_PWRITEV_RMW_AFTER_TAIL); memset(buf, 0, bytes); - ret = bdrv_aligned_pwritev(bs, req, offset, align, + ret = bdrv_aligned_pwritev(bs, req, offset, align, align, &local_qiov, flags & ~BDRV_REQ_ZERO_WRITE); } fail: @@ -1511,7 +1514,7 @@ int coroutine_fn bdrv_co_pwritev(BlockDriverState *bs, bytes = ROUND_UP(bytes, align); } - ret = bdrv_aligned_pwritev(bs, &req, offset, bytes, + ret = bdrv_aligned_pwritev(bs, &req, offset, bytes, align, use_local_qiov ? &local_qiov : qiov, flags); -- cgit v1.2.3