diff options
Diffstat (limited to 'block/bio.c')
-rw-r--r-- | block/bio.c | 142 |
1 files changed, 64 insertions, 78 deletions
diff --git a/block/bio.c b/block/bio.c index 8672179213b9..816d412c06e9 100644 --- a/block/bio.c +++ b/block/bio.c @@ -606,15 +606,15 @@ struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask) } EXPORT_SYMBOL(bio_kmalloc); -void zero_fill_bio(struct bio *bio) +void zero_fill_bio_iter(struct bio *bio, struct bvec_iter start) { struct bio_vec bv; struct bvec_iter iter; - bio_for_each_segment(bv, bio, iter) + __bio_for_each_segment(bv, bio, iter, start) memzero_bvec(&bv); } -EXPORT_SYMBOL(zero_fill_bio); +EXPORT_SYMBOL(zero_fill_bio_iter); /** * bio_truncate - truncate the bio to small size of @new_size @@ -903,9 +903,8 @@ static inline bool bio_full(struct bio *bio, unsigned len) return false; } -static inline bool page_is_mergeable(const struct bio_vec *bv, - struct page *page, unsigned int len, unsigned int off, - bool *same_page) +static bool bvec_try_merge_page(struct bio_vec *bv, struct page *page, + unsigned int len, unsigned int off, bool *same_page) { size_t bv_end = bv->bv_offset + bv->bv_len; phys_addr_t vec_end_addr = page_to_phys(bv->bv_page) + bv_end - 1; @@ -919,49 +918,15 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, return false; *same_page = ((vec_end_addr & PAGE_MASK) == page_addr); - if (*same_page) - return true; - else if (IS_ENABLED(CONFIG_KMSAN)) - return false; - return (bv->bv_page + bv_end / PAGE_SIZE) == (page + off / PAGE_SIZE); -} - -/** - * __bio_try_merge_page - try appending data to an existing bvec. - * @bio: destination bio - * @page: start page to add - * @len: length of the data to add - * @off: offset of the data relative to @page - * @same_page: return if the segment has been merged inside the same page - * - * Try to add the data at @page + @off to the last bvec of @bio. This is a - * useful optimisation for file systems with a block size smaller than the - * page size. - * - * Warn if (@len, @off) crosses pages in case that @same_page is true. - * - * Return %true on success or %false on failure. - */ -static bool __bio_try_merge_page(struct bio *bio, struct page *page, - unsigned int len, unsigned int off, bool *same_page) -{ - if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) - return false; - - if (bio->bi_vcnt > 0) { - struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; - - if (page_is_mergeable(bv, page, len, off, same_page)) { - if (bio->bi_iter.bi_size > UINT_MAX - len) { - *same_page = false; - return false; - } - bv->bv_len += len; - bio->bi_iter.bi_size += len; - return true; - } + if (!*same_page) { + if (IS_ENABLED(CONFIG_KMSAN)) + return false; + if (bv->bv_page + bv_end / PAGE_SIZE != page + off / PAGE_SIZE) + return false; } - return false; + + bv->bv_len += len; + return true; } /* @@ -969,11 +934,10 @@ static bool __bio_try_merge_page(struct bio *bio, struct page *page, * size limit. This is not for normal read/write bios, but for passthrough * or Zone Append operations that we can't split. */ -static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio, - struct page *page, unsigned len, - unsigned offset, bool *same_page) +bool bvec_try_merge_hw_page(struct request_queue *q, struct bio_vec *bv, + struct page *page, unsigned len, unsigned offset, + bool *same_page) { - struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; unsigned long mask = queue_segment_boundary(q); phys_addr_t addr1 = page_to_phys(bv->bv_page) + bv->bv_offset; phys_addr_t addr2 = page_to_phys(page) + offset + len - 1; @@ -982,7 +946,7 @@ static bool bio_try_merge_hw_seg(struct request_queue *q, struct bio *bio, return false; if (bv->bv_len + len > queue_max_segment_size(q)) return false; - return __bio_try_merge_page(bio, page, len, offset, same_page); + return bvec_try_merge_page(bv, page, len, offset, same_page); } /** @@ -1002,33 +966,33 @@ int bio_add_hw_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset, unsigned int max_sectors, bool *same_page) { - struct bio_vec *bvec; - if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) return 0; - if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors) + if (((bio->bi_iter.bi_size + len) >> SECTOR_SHIFT) > max_sectors) return 0; if (bio->bi_vcnt > 0) { - if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page)) + struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; + + if (bvec_try_merge_hw_page(q, bv, page, len, offset, + same_page)) { + bio->bi_iter.bi_size += len; return len; + } + + if (bio->bi_vcnt >= + min(bio->bi_max_vecs, queue_max_segments(q))) + return 0; /* * If the queue doesn't support SG gaps and adding this segment * would create a gap, disallow it. */ - bvec = &bio->bi_io_vec[bio->bi_vcnt - 1]; - if (bvec_gap_to_prev(&q->limits, bvec, offset)) + if (bvec_gap_to_prev(&q->limits, bv, offset)) return 0; } - if (bio_full(bio, len)) - return 0; - - if (bio->bi_vcnt >= queue_max_segments(q)) - return 0; - bvec_set_page(&bio->bi_io_vec[bio->bi_vcnt], page, len, offset); bio->bi_vcnt++; bio->bi_iter.bi_size += len; @@ -1129,11 +1093,21 @@ int bio_add_page(struct bio *bio, struct page *page, { bool same_page = false; - if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) { - if (bio_full(bio, len)) - return 0; - __bio_add_page(bio, page, len, offset); + if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) + return 0; + if (bio->bi_iter.bi_size > UINT_MAX - len) + return 0; + + if (bio->bi_vcnt > 0 && + bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1], + page, len, offset, &same_page)) { + bio->bi_iter.bi_size += len; + return len; } + + if (bio->bi_vcnt >= bio->bi_max_vecs) + return 0; + __bio_add_page(bio, page, len, offset); return len; } EXPORT_SYMBOL(bio_add_page); @@ -1207,13 +1181,18 @@ static int bio_iov_add_page(struct bio *bio, struct page *page, { bool same_page = false; - if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) { - __bio_add_page(bio, page, len, offset); + if (WARN_ON_ONCE(bio->bi_iter.bi_size > UINT_MAX - len)) + return -EIO; + + if (bio->bi_vcnt > 0 && + bvec_try_merge_page(&bio->bi_io_vec[bio->bi_vcnt - 1], + page, len, offset, &same_page)) { + bio->bi_iter.bi_size += len; + if (same_page) + bio_release_page(bio, page); return 0; } - - if (same_page) - bio_release_page(bio, page); + __bio_add_page(bio, page, len, offset); return 0; } @@ -1252,7 +1231,7 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) struct page **pages = (struct page **)bv; ssize_t size, left; unsigned len, i = 0; - size_t offset, trim; + size_t offset; int ret = 0; /* @@ -1281,10 +1260,12 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) nr_pages = DIV_ROUND_UP(offset + size, PAGE_SIZE); - trim = size & (bdev_logical_block_size(bio->bi_bdev) - 1); - iov_iter_revert(iter, trim); + if (bio->bi_bdev) { + size_t trim = size & (bdev_logical_block_size(bio->bi_bdev) - 1); + iov_iter_revert(iter, trim); + size -= trim; + } - size -= trim; if (unlikely(!size)) { ret = -EFAULT; goto out; @@ -1337,6 +1318,9 @@ int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) { int ret = 0; + if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) + return -EIO; + if (iov_iter_is_bvec(iter)) { bio_iov_bvec_set(bio, iter); iov_iter_advance(iter, bio->bi_iter.bi_size); @@ -1490,6 +1474,7 @@ void bio_set_pages_dirty(struct bio *bio) set_page_dirty_lock(bvec->bv_page); } } +EXPORT_SYMBOL_GPL(bio_set_pages_dirty); /* * bio_check_pages_dirty() will check that all the BIO's pages are still dirty. @@ -1549,6 +1534,7 @@ defer: spin_unlock_irqrestore(&bio_dirty_lock, flags); schedule_work(&bio_dirty_work); } +EXPORT_SYMBOL_GPL(bio_check_pages_dirty); static inline bool bio_remaining_done(struct bio *bio) { |