diff options
Diffstat (limited to 'fs/bio.c')
| -rw-r--r-- | fs/bio.c | 36 |
1 files changed, 36 insertions, 0 deletions
@@ -1793,6 +1793,42 @@ void bio_endio_nodec(struct bio *bio, int error) } EXPORT_SYMBOL(bio_endio_nodec); +/** + * bio_split - split a bio + * @bio: bio to split + * @sectors: number of sectors to split from the front of @bio + * @gfp: gfp mask + * @bs: bio set to allocate from + * + * Allocates and returns a new bio which represents @sectors from the start of + * @bio, and updates @bio to represent the remaining sectors. + * + * The newly allocated bio will point to @bio's bi_io_vec; it is the caller's + * responsibility to ensure that @bio is not freed before the split. + */ +struct bio *bio_split(struct bio *bio, int sectors, + gfp_t gfp, struct bio_set *bs) +{ + struct bio *split = NULL; + + BUG_ON(sectors <= 0); + BUG_ON(sectors >= bio_sectors(bio)); + + split = bio_clone_fast(bio, gfp, bs); + if (!split) + return NULL; + + split->bi_iter.bi_size = sectors << 9; + + if (bio_integrity(split)) + bio_integrity_trim(split, 0, sectors); + + bio_advance(bio, split->bi_iter.bi_size); + + return split; +} +EXPORT_SYMBOL(bio_split); + void bio_pair_release(struct bio_pair *bp) { if (atomic_dec_and_test(&bp->cnt)) { |