block: Convert various code to bio_for_each_segment()

With immutable biovecs we don't want code accessing bi_io_vec directly -
the uses this patch changes weren't incorrect since they all own the
bio, but it makes the code harder to audit for no good reason - also,
this will help with multipage bvecs later.

Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Jaegeuk Kim <jaegeuk.kim@samsung.com>
Cc: Joern Engel <joern@logfs.org>
Cc: Prasad Joshi <prasadjoshi.linux@gmail.com>
Cc: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 4 insertions, 7 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 8072cfa8a3b1..5a10c61adafc 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -842,20 +842,17 @@ int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
 
 static int btree_csum_one_bio(struct bio *bio)
 {
-        struct bio_vec *bvec = bio->bi_io_vec;
-        int bio_index = 0;
+        struct bio_vec *bvec;
         struct btrfs_root *root;
-        int ret = 0;
+        int i, ret = 0;
 
-        WARN_ON(bio->bi_vcnt <= 0);
-        while (bio_index < bio->bi_vcnt) {
+        bio_for_each_segment_all(bvec, bio, i) {
                 root = BTRFS_I(bvec->bv_page->mapping->host)->root;
                 ret = csum_dirty_buffer(root, bvec->bv_page);
                 if (ret)
                         break;
-                bio_index++;
-                bvec++;
         }
+
         return ret;
 }