path: root/drivers
diff options
authorMing Lei <ming.lei@redhat.com>2019-12-04 19:31:15 +0800
committerJens Axboe <axboe@kernel.dk>2019-12-04 09:04:26 -0700
commitf1acbf2186dfe761a05ce35c0f36246caed44403 (patch)
treefd7aa83908a5910608eb56fa9d9a8a134af49c07 /drivers
parentbrd: remove max_hw_sectors queue limit (diff)
brd: warn on un-aligned buffer
Queue dma alignment limit requires users(fs, target, ...) of block layer to pass aligned buffer. So far brd doesn't support un-aligned buffer, even though it is easy to support it. However, given brd is often used for debug purpose, and there are other drivers which can't support un-aligned buffer too. So add warning so that brd users know what to fix. Reported-by: Stephen Rust <srust@blockbridge.com> Cc: Stephen Rust <srust@blockbridge.com> Signed-off-by: Ming Lei <ming.lei@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'drivers')
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index c2e5b2ad88bc..a8730cc4db10 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -297,6 +297,10 @@ static blk_qc_t brd_make_request(struct request_queue *q, struct bio *bio)
unsigned int len = bvec.bv_len;
int err;
+ /* Don't support un-aligned buffer */
+ WARN_ON_ONCE((bvec.bv_offset & (SECTOR_SIZE - 1)) ||
+ (len & (SECTOR_SIZE - 1)));
err = brd_do_bvec(brd, bvec.bv_page, len, bvec.bv_offset,
bio_op(bio), sector);
if (err)