1 files changed, 16 insertions, 19 deletions

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 68ebe188446a..11459fe84a29 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -591,7 +591,7 @@ unode_aux_to_inode_list(struct ulist_node *node)
 }
 
 /*
- * We maintain three seperate rbtrees: one for direct refs, one for
+ * We maintain three separate rbtrees: one for direct refs, one for
  * indirect refs which have a key, and one for indirect refs which do not
  * have a key. Each tree does merge on insertion.
  *
@@ -695,7 +695,7 @@ static int resolve_indirect_refs(struct btrfs_fs_info *fs_info,
 		}
 
 		/*
-		 * Now it's a direct ref, put it in the the direct tree. We must
+		 * Now it's a direct ref, put it in the direct tree. We must
 		 * do this last because the ref could be merged/freed here.
 		 */
 		prelim_ref_insert(fs_info, &preftrees->direct, ref, NULL);
@@ -712,7 +712,7 @@ out:
  * read tree blocks and add keys where required.
  */
 static int add_missing_keys(struct btrfs_fs_info *fs_info,
-			    struct preftrees *preftrees)
+			    struct preftrees *preftrees, bool lock)
 {
 	struct prelim_ref *ref;
 	struct extent_buffer *eb;
@@ -737,12 +737,14 @@ static int add_missing_keys(struct btrfs_fs_info *fs_info,
 			free_extent_buffer(eb);
 			return -EIO;
 		}
-		btrfs_tree_read_lock(eb);
+		if (lock)
+			btrfs_tree_read_lock(eb);
 		if (btrfs_header_level(eb) == 0)
 			btrfs_item_key_to_cpu(eb, &ref->key_for_search, 0);
 		else
 			btrfs_node_key_to_cpu(eb, &ref->key_for_search, 0);
-		btrfs_tree_read_unlock(eb);
+		if (lock)
+			btrfs_tree_read_unlock(eb);
 		free_extent_buffer(eb);
 		prelim_ref_insert(fs_info, &preftrees->indirect, ref, NULL);
 		cond_resched();
@@ -1227,7 +1229,7 @@ again:
 
 	btrfs_release_path(path);
 
-	ret = add_missing_keys(fs_info, &preftrees);
+	ret = add_missing_keys(fs_info, &preftrees, path->skip_locking == 0);
 	if (ret)
 		goto out;
 
@@ -1288,11 +1290,15 @@ again:
 					ret = -EIO;
 					goto out;
 				}
-				btrfs_tree_read_lock(eb);
-				btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+
+				if (!path->skip_locking) {
+					btrfs_tree_read_lock(eb);
+					btrfs_set_lock_blocking_read(eb);
+				}
 				ret = find_extent_in_eb(eb, bytenr,
 							*extent_item_pos, &eie, ignore_offset);
-				btrfs_tree_read_unlock_blocking(eb);
+				if (!path->skip_locking)
+					btrfs_tree_read_unlock_blocking(eb);
 				free_extent_buffer(eb);
 				if (ret < 0)
 					goto out;
@@ -1650,7 +1656,7 @@ char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
 		/* make sure we can use eb after releasing the path */
 		if (eb != eb_in) {
 			if (!path->skip_locking)
-				btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+				btrfs_set_lock_blocking_read(eb);
 			path->nodes[0] = NULL;
 			path->locks[0] = 0;
 		}
@@ -2020,9 +2026,6 @@ static int iterate_inode_refs(u64 inum, struct btrfs_root *fs_root,
 			ret = -ENOMEM;
 			break;
 		}
-		extent_buffer_get(eb);
-		btrfs_tree_read_lock(eb);
-		btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
 		btrfs_release_path(path);
 
 		item = btrfs_item_nr(slot);
@@ -2042,7 +2045,6 @@ static int iterate_inode_refs(u64 inum, struct btrfs_root *fs_root,
 			len = sizeof(*iref) + name_len;
 			iref = (struct btrfs_inode_ref *)((char *)iref + len);
 		}
-		btrfs_tree_read_unlock_blocking(eb);
 		free_extent_buffer(eb);
 	}
 
@@ -2083,10 +2085,6 @@ static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root,
 			ret = -ENOMEM;
 			break;
 		}
-		extent_buffer_get(eb);
-
-		btrfs_tree_read_lock(eb);
-		btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
 		btrfs_release_path(path);
 
 		item_size = btrfs_item_size_nr(eb, slot);
@@ -2107,7 +2105,6 @@ static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root,
 			cur_offset += btrfs_inode_extref_name_len(eb, extref);
 			cur_offset += sizeof(*extref);
 		}
-		btrfs_tree_read_unlock_blocking(eb);
 		free_extent_buffer(eb);
 
 		offset++;