dm: Refactor for new bio cloning/splitting

We need to convert the dm code to the new bvec_iter primitives which
respect bi_bvec_done; they also allow us to drastically simplify dm's
bio splitting code.

Also, it's no longer necessary to save/restore the bvec array anymore -
driver conversions for immutable bvecs are done, so drivers should never
be modifying it.

Also kill bio_sector_offset(), dm was the only user and it doesn't make
much sense anymore.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alasdair Kergon <agk@redhat.com>
Cc: dm-devel@redhat.com
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Kent Overstreet
2013-10-29 17:17:49 -07:00
parent 5341a6278b
commit 1c3b13e64c
4 changed files with 20 additions and 253 deletions

View File

@@ -330,7 +330,6 @@ extern void bio_put(struct bio *);
extern void __bio_clone_fast(struct bio *, struct bio *);
extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
extern void __bio_clone(struct bio *, struct bio *);
extern struct bio *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
extern struct bio_set *fs_bio_set;
@@ -370,7 +369,6 @@ extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
unsigned int, unsigned int);
extern int bio_get_nr_vecs(struct block_device *);
extern sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
unsigned long, unsigned int, int, gfp_t);
struct sg_iovec;