From 320ea869a12cec206756207c6ca5f817ec45c7f2 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Mon, 12 Aug 2019 17:39:56 +0200 Subject: [PATCH] block: improve the gap check in __bio_add_pc_page If we can add more data into an existing segment we do not create a gap per definition, so move the check for a gap after the attempt to merge into the segment. Signed-off-by: Christoph Hellwig Reviewed-by: Johannes Thumshirn Signed-off-by: Jens Axboe --- block/bio.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/block/bio.c b/block/bio.c index 54769659a434..537d71a30e56 100644 --- a/block/bio.c +++ b/block/bio.c @@ -710,18 +710,18 @@ static int __bio_add_pc_page(struct request_queue *q, struct bio *bio, goto done; } - /* - * If the queue doesn't support SG gaps and adding this - * offset would create a gap, disallow it. - */ - if (bvec_gap_to_prev(q, bvec, offset)) - return 0; - if (page_is_mergeable(bvec, page, len, offset, &same_page) && can_add_page_to_seg(q, bvec, page, len, offset)) { bvec->bv_len += len; goto done; } + + /* + * If the queue doesn't support SG gaps and adding this segment + * would create a gap, disallow it. + */ + if (bvec_gap_to_prev(q, bvec, offset)) + return 0; } if (bio_full(bio, len)) -- 2.11.0