btrfs: cleanup duplicate bio allocating functions

extent_bio_alloc() and compressed_bio_alloc() are similar, cleanup
similar source code.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

3 files changed, 8 insertions, 18 deletions

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 7845d1f7d1d..b50bc4bd5c5 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -91,23 +91,10 @@ static inline int compressed_bio_size(struct btrfs_root *root,
 static struct bio *compressed_bio_alloc(struct block_device *bdev,
                                         u64 first_byte, gfp_t gfp_flags)
 {
-        struct bio *bio;
         int nr_vecs;
 
         nr_vecs = bio_get_nr_vecs(bdev);
-        bio = bio_alloc(gfp_flags, nr_vecs);
-
-        if (bio == NULL && (current->flags & PF_MEMALLOC)) {
-                while (!bio && (nr_vecs /= 2))
-                        bio = bio_alloc(gfp_flags, nr_vecs);
-        }
-
-        if (bio) {
-                bio->bi_size = 0;
-                bio->bi_bdev = bdev;
-                bio->bi_sector = first_byte >> 9;
-        }
-        return bio;
+        return btrfs_bio_alloc(bdev, first_byte >> 9, nr_vecs, gfp_flags);
 }
 
 static int check_compressed_csum(struct inode *inode,
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 3b7eaee0f91..f60aa3c35c2 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1828,9 +1828,9 @@ static void end_bio_extent_preparewrite(struct bio *bio, int err)
         bio_put(bio);
 }
 
-static struct bio *
-extent_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
-                 gfp_t gfp_flags)
+struct bio *
+btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
+                gfp_t gfp_flags)
 {
         struct bio *bio;
 
@@ -1919,7 +1919,7 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree,
         else
                 nr = bio_get_nr_vecs(bdev);
 
-        bio = extent_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
+        bio = btrfs_bio_alloc(bdev, sector, nr, GFP_NOFS | __GFP_HIGH);
 
         bio_add_page(bio, page, page_size, offset);
         bio->bi_end_io = end_io_func;
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 1c6d4f342ef..4183c8178f0 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -310,4 +310,7 @@ int extent_clear_unlock_delalloc(struct inode *inode,
                                 struct extent_io_tree *tree,
                                 u64 start, u64 end, struct page *locked_page,
                                 unsigned long op);
+struct bio *
+btrfs_bio_alloc(struct block_device *bdev, u64 first_sector, int nr_vecs,
+                gfp_t gfp_flags);
 #endif