From 8423ae3d7a3cfe084865262cfaeba1359d405182 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Mon, 10 Feb 2014 17:45:50 -0800 Subject: block: Fix cloning of discard/write same bios Immutable biovecs changed the way bio segments are treated in such a way that bio_for_each_segment() cannot now do what we want for discard/write same bios, since bi_size means something completely different for them. Fortunately discard and write same bios never have more than a single biovec, so bio_for_each_segment() is unnecessary and not terribly meaningful for them, but we still have to special case them in a few places. Signed-off-by: Kent Overstreet Tested-by: Richard W.M. Jones Signed-off-by: Jens Axboe --- include/linux/bio.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'include/linux') diff --git a/include/linux/bio.h b/include/linux/bio.h index d6791bba8264..5a4d39b4686b 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -250,6 +250,17 @@ static inline unsigned bio_segments(struct bio *bio) struct bio_vec bv; struct bvec_iter iter; + /* + * We special case discard/write same, because they interpret bi_size + * differently: + */ + + if (bio->bi_rw & REQ_DISCARD) + return 1; + + if (bio->bi_rw & REQ_WRITE_SAME) + return 1; + bio_for_each_segment(bv, bio, iter) segs++; -- cgit v1.2.3