Now we only check if DMA IO buffer is aligned to queue_dma_alignment()
for pass-through request, and it isn't done for normal IO request.
Given the check has to be done on each bvec, it isn't efficient to add the
check in generic_make_request_checks().
This patch addes one WARN in blk_queue_split() for capturing this issue.
Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Cc: Dave Chinner <dchinner@xxxxxxxxxx>
Cc: Linux FS Devel <linux-fsdevel@xxxxxxxxxxxxxxx>
Cc: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Cc: xfs@xxxxxxxxxxxxxxx
Cc: Dave Chinner <dchinner@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Bart Van Assche <bvanassche@xxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
---
block/blk-merge.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 42a46744c11b..d2dbd508cb6d 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -174,6 +174,8 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
const unsigned max_sectors = get_max_io_size(q, bio);
bio_for_each_segment(bv, bio, iter) {
+ WARN_ON_ONCE(queue_dma_alignment(q) & bv.bv_offset);
+
/*
* If the queue doesn't support SG gaps and adding this
* offset would create a gap, disallow it.
--
2.9.5
