diff options
Diffstat (limited to 'block/bio.c')
| -rw-r--r-- | block/bio.c | 65 |
1 files changed, 40 insertions, 25 deletions
diff --git a/block/bio.c b/block/bio.c index 21cbaa6a1c20..aad0a6dad4f9 100644 --- a/block/bio.c +++ b/block/bio.c @@ -748,9 +748,14 @@ static inline bool page_is_mergeable(const struct bio_vec *bv, return true; } -static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, - struct page *page, unsigned len, unsigned offset, - bool *same_page) +/* + * Try to merge a page into a segment, while obeying the hardware segment + * 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) { struct bio_vec *bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; unsigned long mask = queue_segment_boundary(q); @@ -765,38 +770,32 @@ static bool bio_try_merge_pc_page(struct request_queue *q, struct bio *bio, } /** - * __bio_add_pc_page - attempt to add page to passthrough bio - * @q: the target queue - * @bio: destination bio - * @page: page to add - * @len: vec entry length - * @offset: vec entry offset - * @same_page: return if the merge happen inside the same page - * - * Attempt to add a page to the bio_vec maplist. This can fail for a - * number of reasons, such as the bio being full or target block device - * limitations. The target block device must allow bio's up to PAGE_SIZE, - * so it is always possible to add a single page to an empty bio. + * bio_add_hw_page - attempt to add a page to a bio with hw constraints + * @q: the target queue + * @bio: destination bio + * @page: page to add + * @len: vec entry length + * @offset: vec entry offset + * @max_sectors: maximum number of sectors that can be added + * @same_page: return if the segment has been merged inside the same page * - * This should only be used by passthrough bios. + * Add a page to a bio while respecting the hardware max_sectors, max_segment + * and gap limitations. */ -int __bio_add_pc_page(struct request_queue *q, struct bio *bio, +int bio_add_hw_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset, - bool *same_page) + unsigned int max_sectors, bool *same_page) { struct bio_vec *bvec; - /* - * cloned bio must not modify vec list - */ - if (unlikely(bio_flagged(bio, BIO_CLONED))) + if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED))) return 0; - if (((bio->bi_iter.bi_size + len) >> 9) > queue_max_hw_sectors(q)) + if (((bio->bi_iter.bi_size + len) >> 9) > max_sectors) return 0; if (bio->bi_vcnt > 0) { - if (bio_try_merge_pc_page(q, bio, page, len, offset, same_page)) + if (bio_try_merge_hw_seg(q, bio, page, len, offset, same_page)) return len; /* @@ -823,11 +822,27 @@ int __bio_add_pc_page(struct request_queue *q, struct bio *bio, return len; } +/** + * bio_add_pc_page - attempt to add page to passthrough bio + * @q: the target queue + * @bio: destination bio + * @page: page to add + * @len: vec entry length + * @offset: vec entry offset + * + * Attempt to add a page to the bio_vec maplist. This can fail for a + * number of reasons, such as the bio being full or target block device + * limitations. The target block device must allow bio's up to PAGE_SIZE, + * so it is always possible to add a single page to an empty bio. + * + * This should only be used by passthrough bios. + */ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { bool same_page = false; - return __bio_add_pc_page(q, bio, page, len, offset, &same_page); + return bio_add_hw_page(q, bio, page, len, offset, + queue_max_hw_sectors(q), &same_page); } EXPORT_SYMBOL(bio_add_pc_page); |