block: Add bio_alloc_pages()

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

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: NeilBrown <neilb@suse.de>
This commit is contained in:
Kent Overstreet 2012-09-10 14:03:28 -07:00
parent cb34e057ad
commit a07876064a
3 changed files with 32 additions and 13 deletions

View File

@ -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]);

View File

@ -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

View File

@ -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);