From 7759eb23fd9808a2e4498cf36a798ed65cde78ae Mon Sep 17 00:00:00 2001 From: Ming Lei Date: Wed, 5 Sep 2018 15:45:54 -0600 Subject: block: remove bio_rewind_iter() It is pointed that bio_rewind_iter() is one very bad API[1]: 1) bio size may not be restored after rewinding 2) it causes some bogus change, such as 5151842b9d8732 (block: reset bi_iter.bi_done after splitting bio) 3) rewinding really makes things complicated wrt. bio splitting 4) unnecessary updating of .bi_done in fast path [1] https://marc.info/?t=153549924200005&r=1&w=2 So this patch takes Kent's suggestion to restore one bio into its original state via saving bio iterator(struct bvec_iter) in bio_integrity_prep(), given now bio_rewind_iter() is only used by bio integrity code. Cc: Dmitry Monakhov Cc: Hannes Reinecke Suggested-by: Kent Overstreet Acked-by: Kent Overstreet Reviewed-by: Christoph Hellwig Signed-off-by: Ming Lei Signed-off-by: Jens Axboe --- include/linux/bvec.h | 3 --- 1 file changed, 3 deletions(-) (limited to 'include/linux/bvec.h') diff --git a/include/linux/bvec.h b/include/linux/bvec.h index fe7a22dd133b..02c73c6aa805 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -40,8 +40,6 @@ struct bvec_iter { unsigned int bi_idx; /* current index into bvl_vec */ - unsigned int bi_done; /* number of bytes completed */ - unsigned int bi_bvec_done; /* number of bytes completed in current bvec */ }; @@ -85,7 +83,6 @@ static inline bool bvec_iter_advance(const struct bio_vec *bv, bytes -= len; iter->bi_size -= len; iter->bi_bvec_done += len; - iter->bi_done += len; if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) { iter->bi_bvec_done = 0; -- cgit