From a07876064a0b73ab5ef1ebcf14b1cf0231c07858 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Mon, 10 Sep 2012 14:03:28 -0700 Subject: [PATCH] block: Add bio_alloc_pages() More utility code to replace stuff that's getting open coded. Signed-off-by: Kent Overstreet CC: Jens Axboe CC: NeilBrown --- drivers/md/raid1.c | 16 +++------------- fs/bio.c | 28 ++++++++++++++++++++++++++++ include/linux/bio.h | 1 + 3 files changed, 32 insertions(+), 13 deletions(-) diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index a7ea954abe1d..aeb4e3f74791 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -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]); diff --git a/fs/bio.c b/fs/bio.c index fe3aee90c988..e545a440d376 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -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 diff --git a/include/linux/bio.h b/include/linux/bio.h index be2efa09f9bf..e25378f2f408 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -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); -- 2.20.1