From 20d0189b1012a37d2533a87fb451f7852f2418d1 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Sat, 23 Nov 2013 18:21:01 -0800 Subject: block: Introduce new bio_split() The new bio_split() can split arbitrary bios - it's not restricted to single page bios, like the old bio_split() (previously renamed to bio_pair_split()). It also has different semantics - it doesn't allocate a struct bio_pair, leaving it up to the caller to handle completions. Then convert the existing bio_pair_split() users to the new bio_split() - and also nvme, which was open coding bio splitting. (We have to take that BUG_ON() out of bio_integrity_trim() because this bio_split() needs to use it, and there's no reason it has to be used on bios marked as cloned; BIO_CLONED doesn't seem to have clearly documented semantics anyways.) Signed-off-by: Kent Overstreet Cc: Jens Axboe Cc: Martin K. Petersen Cc: Matthew Wilcox Cc: Keith Busch Cc: Vishal Verma Cc: Jiri Kosina Cc: Neil Brown --- drivers/md/bcache/io.c | 82 ++------------------------------------------------ 1 file changed, 2 insertions(+), 80 deletions(-) (limited to 'drivers/md/bcache/io.c') diff --git a/drivers/md/bcache/io.c b/drivers/md/bcache/io.c index 522f95778443..fa028fa82df4 100644 --- a/drivers/md/bcache/io.c +++ b/drivers/md/bcache/io.c @@ -11,84 +11,6 @@ #include -/** - * bch_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. - * - * If bio_sectors(@bio) was less than or equal to @sectors, returns @bio - * unchanged. - * - * The newly allocated bio will point to @bio's bi_io_vec, if the split was on a - * bvec boundry; it is the caller's responsibility to ensure that @bio is not - * freed before the split. - */ -struct bio *bch_bio_split(struct bio *bio, int sectors, - gfp_t gfp, struct bio_set *bs) -{ - unsigned vcnt = 0, nbytes = sectors << 9; - struct bio_vec bv; - struct bvec_iter iter; - struct bio *ret = NULL; - - BUG_ON(sectors <= 0); - - if (sectors >= bio_sectors(bio)) - return bio; - - if (bio->bi_rw & REQ_DISCARD) { - ret = bio_alloc_bioset(gfp, 1, bs); - if (!ret) - return NULL; - goto out; - } - - bio_for_each_segment(bv, bio, iter) { - vcnt++; - - if (nbytes <= bv.bv_len) - break; - - nbytes -= bv.bv_len; - } - - ret = bio_alloc_bioset(gfp, vcnt, bs); - if (!ret) - return NULL; - - bio_for_each_segment(bv, bio, iter) { - ret->bi_io_vec[ret->bi_vcnt++] = bv; - - if (ret->bi_vcnt == vcnt) - break; - } - - ret->bi_io_vec[ret->bi_vcnt - 1].bv_len = nbytes; -out: - ret->bi_bdev = bio->bi_bdev; - ret->bi_iter.bi_sector = bio->bi_iter.bi_sector; - ret->bi_iter.bi_size = sectors << 9; - ret->bi_rw = bio->bi_rw; - - if (bio_integrity(bio)) { - if (bio_integrity_clone(ret, bio, gfp)) { - bio_put(ret); - return NULL; - } - - bio_integrity_trim(ret, 0, bio_sectors(ret)); - } - - bio_advance(bio, ret->bi_iter.bi_size); - - return ret; -} - static unsigned bch_bio_max_sectors(struct bio *bio) { struct request_queue *q = bdev_get_queue(bio->bi_bdev); @@ -172,8 +94,8 @@ void bch_generic_make_request(struct bio *bio, struct bio_split_pool *p) bio_get(bio); do { - n = bch_bio_split(bio, bch_bio_max_sectors(bio), - GFP_NOIO, s->p->bio_split); + n = bio_next_split(bio, bch_bio_max_sectors(bio), + GFP_NOIO, s->p->bio_split); n->bi_end_io = bch_bio_submit_split_endio; n->bi_private = &s->cl; -- cgit v1.2.3