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author | Ming Lei <ming.lei@redhat.com> | 2019-02-15 19:13:19 +0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2019-02-15 08:40:11 -0700 |
commit | 6dc4f100c175dd0511ae8674786e7c9006cdfbfa (patch) | |
tree | b8e5204ca6eec1275187496f2d6c069643e478dc /include/linux | |
parent | 2e1f4f4d2481d8bf111904c3e45fc0c4c94bf76e (diff) | |
download | linux-6dc4f100c175dd0511ae8674786e7c9006cdfbfa.tar.gz linux-6dc4f100c175dd0511ae8674786e7c9006cdfbfa.tar.bz2 linux-6dc4f100c175dd0511ae8674786e7c9006cdfbfa.zip |
block: allow bio_for_each_segment_all() to iterate over multi-page bvec
This patch introduces one extra iterator variable to bio_for_each_segment_all(),
then we can allow bio_for_each_segment_all() to iterate over multi-page bvec.
Given it is just one mechannical & simple change on all bio_for_each_segment_all()
users, this patch does tree-wide change in one single patch, so that we can
avoid to use a temporary helper for this conversion.
Reviewed-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/bio.h | 11 | ||||
-rw-r--r-- | include/linux/bvec.h | 30 |
2 files changed, 39 insertions, 2 deletions
diff --git a/include/linux/bio.h b/include/linux/bio.h index 7ef8a7505c0a..089370eb84d9 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -128,12 +128,19 @@ 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) \ - for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++) +#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) 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 21f76bad7be2..30a57b68d017 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -45,6 +45,12 @@ struct bvec_iter { current bvec */ }; +struct bvec_iter_all { + struct bio_vec bv; + int idx; + unsigned done; +}; + /* * various member access, note that bio_data should of course not be used * on highmem page vectors @@ -131,6 +137,30 @@ static inline bool bvec_iter_advance(const struct bio_vec *bv, .bi_bvec_done = 0, \ } +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; + + return &iter_all->bv; +} + +static inline void mp_bvec_next_segment(const struct bio_vec *bvec, + struct bvec_iter_all *iter_all) +{ + struct bio_vec *bv = &iter_all->bv; + + if (bv->bv_page) { + bv->bv_page = nth_page(bv->bv_page, 1); + bv->bv_offset = 0; + } else { + bv->bv_page = bvec->bv_page; + bv->bv_offset = bvec->bv_offset; + } + bv->bv_len = min_t(unsigned int, PAGE_SIZE - bv->bv_offset, + bvec->bv_len - iter_all->done); +} + /* * Get the last single-page segment from the multi-page bvec and store it * in @seg |