Btrfs: switch to btrfs_previous_extent_item()

Since we have introduced btrfs_previous_extent_item() to search previous
extent item, just switch into it.

Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
Reviewed-by: Filipe Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fb.com>

1 files changed, 6 insertions, 31 deletions

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 903fe68e017b..a88da721dfc5 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -1325,38 +1325,13 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
         if (ret < 0)
                 return ret;
 
-        while (1) {
-                u32 nritems;
-                if (path->slots[0] == 0) {
-                        btrfs_set_path_blocking(path);
-                        ret = btrfs_prev_leaf(fs_info->extent_root, path);
-                        if (ret != 0) {
-                                if (ret > 0) {
-                                        pr_debug("logical %llu is not within "
-                                                 "any extent\n", logical);
-                                        ret = -ENOENT;
-                                }
-                                return ret;
-                        }
-                } else {
-                        path->slots[0]--;
-                }
-                nritems = btrfs_header_nritems(path->nodes[0]);
-                if (nritems == 0) {
-                        pr_debug("logical %llu is not within any extent\n",
-                                 logical);
-                        return -ENOENT;
-                }
-                if (path->slots[0] == nritems)
-                        path->slots[0]--;
-
-                btrfs_item_key_to_cpu(path->nodes[0], found_key,
-                                      path->slots[0]);
-                if (found_key->type == BTRFS_EXTENT_ITEM_KEY ||
-                    found_key->type == BTRFS_METADATA_ITEM_KEY)
-                        break;
+        ret = btrfs_previous_extent_item(fs_info->extent_root, path, 0);
+        if (ret) {
+                if (ret > 0)
+                        ret = -ENOENT;
+                return ret;
         }
-
+        btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]);
         if (found_key->type == BTRFS_METADATA_ITEM_KEY)
                 size = fs_info->extent_root->leafsize;
         else if (found_key->type == BTRFS_EXTENT_ITEM_KEY)