From a07876064a0b73ab5ef1ebcf14b1cf0231c07858 Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Mon, 10 Sep 2012 14:03:28 -0700 Subject: 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 --- fs/bio.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) (limited to 'fs/bio.c') 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 -- cgit v1.2.3