block: move bio_alloc_pages() to bcache

[sfrench/cifs-2.6.git] / drivers / md / bcache / util.c

diff --git a/drivers/md/bcache/util.c b/drivers/md/bcache/util.c
index 61813d23001543932b05857b6f9143be908242b4..a23cd6a14b7427acd9644992d47ee209f8dad092 100644 (file)
--- a/drivers/md/bcache/util.c
+++ b/drivers/md/bcache/util.c
@@ -283,6 +283,33 @@ start:             bv->bv_len      = min_t(size_t, PAGE_SIZE - bv->bv_offset,
        }
 }
 
+/**
+ * bch_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 bch_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;
+}
+
 /*
  * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group (Any
  * use permitted, subject to terms of PostgreSQL license; see.)