From aaeee62c841cc1e48231e1d60c304d2da9c4e41c Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Sat, 2 Mar 2019 16:43:44 +0800 Subject: [PATCH] block: fix updating bio's front segment size When the current bvec can be merged to the 1st segment, the bio's front segment size has to be updated. However, dcebd755926b doesn't consider that case, then bio's front segment size may not be correct. This patch fixes this issue. Cc: Christoph Hellwig Cc: Omar Sandoval Fixes: dcebd755926b ("block: use bio_for_each_bvec() to compute multi-page bvec count") Signed-off-by: Ming Lei Signed-off-by: Jens Axboe --- block/blk-merge.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/block/blk-merge.c b/block/blk-merge.c index 9402a7c3ba22..22467f475ab4 100644 --- a/block/blk-merge.c +++ b/block/blk-merge.c @@ -277,6 +277,9 @@ static struct bio *blk_bio_segment_split(struct request_queue *q, bvprvp = &bvprv; sectors += bv.bv_len >> 9; + if (nsegs == 1 && seg_size > front_seg_size) + front_seg_size = seg_size; + continue; } new_segment: @@ -401,6 +404,11 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q, seg_size += bv.bv_len; bvprv = bv; + + if (nr_phys_segs == 1 && seg_size > + front_seg_size) + front_seg_size = seg_size; + continue; } new_segment: -- 2.30.2