Commit a0787606 authored by Kent Overstreet's avatar Kent Overstreet
Browse files

block: Add bio_alloc_pages() 



More utility code to replace stuff that's getting open coded.

Signed-off-by: default avatarKent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: NeilBrown <neilb@suse.de>
parent cb34e057

drivers/md/raid1.c

+3 −13
Original line number Diff line number Diff line
@@ -92,7 +92,6 @@ static void r1bio_pool_free(void *r1_bio, void *data) 
static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)

{

	struct pool_info *pi = data;

	struct page *page;

	struct r1bio *r1_bio;

	struct bio *bio;

	int i, j;
@@ -122,14 +121,10 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data) 
		j = 1;

	while(j--) {

		bio = r1_bio->bios[j];

		for (i = 0; i < RESYNC_PAGES; i++) {

			page = alloc_page(gfp_flags);

			if (unlikely(!page))

				goto out_free_pages;

		bio->bi_vcnt = RESYNC_PAGES;



			bio->bi_io_vec[i].bv_page = page;

			bio->bi_vcnt = i+1;

		}

		if (bio_alloc_pages(bio, gfp_flags))

			goto out_free_bio;

	}

	/* If not user-requests, copy the page pointers to all bios */

	if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) {
@@ -143,11 +138,6 @@ static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data) 


	return r1_bio;



out_free_pages:

	for (j=0 ; j < pi->raid_disks; j++)

		for (i=0; i < r1_bio->bios[j]->bi_vcnt ; i++)

			put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page);

	j = -1;

out_free_bio:

	while (++j < pi->raid_disks)

		bio_put(r1_bio->bios[j]);

fs/bio.c

+28 −0
Original line number Diff line number Diff line
@@ -829,6 +829,34 @@ void bio_advance(struct bio *bio, unsigned bytes) 
}

EXPORT_SYMBOL(bio_advance);



/**

 * bio_alloc_pages - allocates a single page for each bvec in a bio

 * @bio: bio to allocate pages for

 * @gfp_mask: flags for allocation

 *

 * Allocates pages up to @bio->bi_vcnt.

 *

 * Returns 0 on success, -ENOMEM on failure. On failure, any allocated pages are

 * freed.

 */

int bio_alloc_pages(struct bio *bio, gfp_t gfp_mask)

{

	int i;

	struct bio_vec *bv;



	bio_for_each_segment_all(bv, bio, i) {

		bv->bv_page = alloc_page(gfp_mask);

		if (!bv->bv_page) {

			while (--bv >= bio->bi_io_vec)

				__free_page(bv->bv_page);

			return -ENOMEM;

		}

	}



	return 0;

}

EXPORT_SYMBOL(bio_alloc_pages);



/**

 * bio_copy_data - copy contents of data buffers from one chain of bios to

 * another

include/linux/bio.h

+1 −0
Original line number Diff line number Diff line
@@ -298,6 +298,7 @@ static inline void bio_flush_dcache_pages(struct bio *bi) 
#endif



extern void bio_copy_data(struct bio *dst, struct bio *src);

extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);



extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,

				 unsigned long, unsigned int, int, gfp_t);