Commit 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec") changes bio_for_each_segment_all() to use for-inside-for. This way breaks all bio_for_each_segment_all() call with error out branch via 'break', since now 'break' can only break from the inner loop. Fixes this issue by implementing bio_for_each_segment_all() via single 'for' loop, and now the logic is very similar with normal bvec iterator. Cc: Qu Wenruo <quwenruo.btrfs@xxxxxxx> Cc: linux-btrfs@xxxxxxxxxxxxxxx Cc: linux-fsdevel@xxxxxxxxxxxxxxx Cc: Omar Sandoval <osandov@xxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Reported-and-Tested-by: Qu Wenruo <quwenruo.btrfs@xxxxxxx> Fixes: 6dc4f100c175 ("block: allow bio_for_each_segment_all() to iterate over multi-page bvec") Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx> --- include/linux/bio.h | 14 +++++--------- include/linux/bvec.h | 20 +++++++++++++------- 2 files changed, 18 insertions(+), 16 deletions(-) diff --git a/include/linux/bio.h b/include/linux/bio.h index bb6090aa165d..7bd7e64e02f8 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -120,19 +120,15 @@ static inline bool bio_full(struct bio *bio) return bio->bi_vcnt >= bio->bi_max_vecs; } -#define mp_bvec_for_each_segment(bv, bvl, i, iter_all) \ - for (bv = bvec_init_iter_all(&iter_all); \ - (iter_all.done < (bvl)->bv_len) && \ - (mp_bvec_next_segment((bvl), &iter_all), 1); \ - iter_all.done += bv->bv_len, i += 1) - /* * drivers should _never_ use the all version - the bio may have been split * before it got to the driver and the driver won't own all of it */ -#define bio_for_each_segment_all(bvl, bio, i, iter_all) \ - for (i = 0, iter_all.idx = 0; iter_all.idx < (bio)->bi_vcnt; iter_all.idx++) \ - mp_bvec_for_each_segment(bvl, &((bio)->bi_io_vec[iter_all.idx]), i, iter_all) +#define bio_for_each_segment_all(bvl, bio, i, iter_all) \ + for (i = 0, bvl = bvec_init_iter_all(&iter_all); \ + iter_all.idx < (bio)->bi_vcnt && \ + (mp_bvec_advance(&((bio)->bi_io_vec[iter_all.idx]), \ + &iter_all), 1); i++) static inline void bio_advance_iter(struct bio *bio, struct bvec_iter *iter, unsigned bytes) diff --git a/include/linux/bvec.h b/include/linux/bvec.h index f6275c4da13a..6e4996dfc847 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -48,7 +48,7 @@ struct bvec_iter { struct bvec_iter_all { struct bio_vec bv; int idx; - unsigned done; + unsigned bv_done; }; static inline struct page *bvec_nth_page(struct page *page, int idx) @@ -145,18 +145,18 @@ static inline bool bvec_iter_advance(const struct bio_vec *bv, static inline struct bio_vec *bvec_init_iter_all(struct bvec_iter_all *iter_all) { - iter_all->bv.bv_page = NULL; - iter_all->done = 0; + iter_all->bv_done = 0; + iter_all->idx = 0; return &iter_all->bv; } -static inline void mp_bvec_next_segment(const struct bio_vec *bvec, - struct bvec_iter_all *iter_all) +static inline void mp_bvec_advance(const struct bio_vec *bvec, + struct bvec_iter_all *iter_all) { struct bio_vec *bv = &iter_all->bv; - if (bv->bv_page) { + if (iter_all->bv_done) { bv->bv_page = nth_page(bv->bv_page, 1); bv->bv_offset = 0; } else { @@ -164,7 +164,13 @@ static inline void mp_bvec_next_segment(const struct bio_vec *bvec, bv->bv_offset = bvec->bv_offset; } bv->bv_len = min_t(unsigned int, PAGE_SIZE - bv->bv_offset, - bvec->bv_len - iter_all->done); + bvec->bv_len - iter_all->bv_done); + iter_all->bv_done += bv->bv_len; + + if (iter_all->bv_done == bvec->bv_len) { + iter_all->idx++; + iter_all->bv_done = 0; + } } /* -- 2.9.5