Commit 59db8ba2 authored Nov 08, 2019 by Ming Lei Committed by Jens Axboe Nov 08, 2019

block: still try to split bio if the bvec crosses pages



Some device may set segment boundary as PAGE_SIZE - 1. If the bvec
crosses pages, and meantime its length is <= PAGE_SIZE, we still need
to split the bvec into 2 segments.

Fixes this issue by still splitting bio if the single bvec crosses
pages.

Reported-by: kernel test robot <lkp@intel.com>
Fixes: fa532287 (block: avoid blk_bio_segment_split for small I/O operations)
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent 1d156646

block/blk-merge.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -319,7 +319,8 @@ void __blk_queue_split(struct request_queue q, struct bio *bio,
		*/
		if (!q->limits.chunk_sectors &&
		(*bio)->bi_vcnt == 1 &&
		(*bio)->bi_io_vec[0].bv_len <= PAGE_SIZE) {
		((*bio)->bi_io_vec[0].bv_len +
		(*bio)->bi_io_vec[0].bv_offset) <= PAGE_SIZE) {
		*nr_segs = 1;
		break;
		}

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