diff options
Diffstat (limited to 'include/linux/bvec.h')
| -rw-r--r-- | include/linux/bvec.h | 56 |
1 files changed, 33 insertions, 23 deletions
diff --git a/include/linux/bvec.h b/include/linux/bvec.h index ba8f52d48b94..d36dd476feda 100644 --- a/include/linux/bvec.h +++ b/include/linux/bvec.h @@ -22,11 +22,8 @@ struct page; * @bv_len: Number of bytes in the address range. * @bv_offset: Start of the address range relative to the start of @bv_page. * - * The following holds for a bvec if n * PAGE_SIZE < bv_offset + bv_len: - * - * nth_page(@bv_page, n) == @bv_page + n - * - * This holds because page_is_mergeable() checks the above property. + * All pages within a bio_vec starting from @bv_page are contiguous and + * can simply be iterated (see bvec_advance()). */ struct bio_vec { struct page *bv_page; @@ -57,9 +54,12 @@ static inline void bvec_set_page(struct bio_vec *bv, struct page *page, * @offset: offset into the folio */ static inline void bvec_set_folio(struct bio_vec *bv, struct folio *folio, - unsigned int len, unsigned int offset) + size_t len, size_t offset) { - bvec_set_page(bv, &folio->page, len, offset); + unsigned long nr = offset / PAGE_SIZE; + + WARN_ON_ONCE(len > UINT_MAX); + bvec_set_page(bv, folio_page(folio, nr), len, offset % PAGE_SIZE); } /** @@ -75,14 +75,27 @@ static inline void bvec_set_virt(struct bio_vec *bv, void *vaddr, } struct bvec_iter { - sector_t bi_sector; /* device address in 512 byte - sectors */ - unsigned int bi_size; /* residual I/O count */ - - unsigned int bi_idx; /* current index into bvl_vec */ - - unsigned int bi_bvec_done; /* number of bytes completed in - current bvec */ + /* + * Current device address in 512 byte sectors. Only updated by the bio + * iter wrappers and not the bvec iterator helpers themselves. + */ + sector_t bi_sector; + + /* + * Remaining size in bytes. + */ + unsigned int bi_size; + + /* + * Current index into the bvec array. This indexes into `bi_io_vec` when + * iterating a bvec array that is part of a `bio`. + */ + unsigned int bi_idx; + + /* + * Current offset in the bvec entry pointed to by `bi_idx`. + */ + unsigned int bi_bvec_done; } __packed __aligned(4); struct bvec_iter_all { @@ -184,14 +197,11 @@ static inline void bvec_iter_advance_single(const struct bio_vec *bv, ((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \ bvec_iter_advance_single((bio_vec), &(iter), (bvl).bv_len)) -/* for iterating one bio from start to end */ -#define BVEC_ITER_ALL_INIT (struct bvec_iter) \ -{ \ - .bi_sector = 0, \ - .bi_size = UINT_MAX, \ - .bi_idx = 0, \ - .bi_bvec_done = 0, \ -} +#define for_each_mp_bvec(bvl, bio_vec, iter, start) \ + for (iter = (start); \ + (iter).bi_size && \ + ((bvl = mp_bvec_iter_bvec((bio_vec), (iter))), 1); \ + bvec_iter_advance_single((bio_vec), &(iter), (bvl).bv_len)) static inline struct bio_vec *bvec_init_iter_all(struct bvec_iter_all *iter_all) { |