1 files changed, 17 insertions, 30 deletions

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 6dcdb2ec9211..80e8472d618b 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -148,8 +148,7 @@ int __init btrfs_prelim_ref_init(void)
 
 void btrfs_prelim_ref_exit(void)
 {
-	if (btrfs_prelim_ref_cache)
-		kmem_cache_destroy(btrfs_prelim_ref_cache);
+	kmem_cache_destroy(btrfs_prelim_ref_cache);
 }
 
 /*
@@ -355,7 +354,7 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
 
 	index = srcu_read_lock(&fs_info->subvol_srcu);
 
-	root = btrfs_read_fs_root_no_name(fs_info, &root_key);
+	root = btrfs_get_fs_root(fs_info, &root_key, false);
 	if (IS_ERR(root)) {
 		srcu_read_unlock(&fs_info->subvol_srcu, index);
 		ret = PTR_ERR(root);
@@ -520,13 +519,10 @@ static inline int ref_for_same_block(struct __prelim_ref *ref1,
 static int __add_missing_keys(struct btrfs_fs_info *fs_info,
 			      struct list_head *head)
 {
-	struct list_head *pos;
+	struct __prelim_ref *ref;
 	struct extent_buffer *eb;
 
-	list_for_each(pos, head) {
-		struct __prelim_ref *ref;
-		ref = list_entry(pos, struct __prelim_ref, list);
-
+	list_for_each_entry(ref, head, list) {
 		if (ref->parent)
 			continue;
 		if (ref->key_for_search.type)
@@ -563,31 +559,20 @@ static int __add_missing_keys(struct btrfs_fs_info *fs_info,
  */
 static void __merge_refs(struct list_head *head, int mode)
 {
-	struct list_head *pos1;
+	struct __prelim_ref *pos1;
 
-	list_for_each(pos1, head) {
-		struct list_head *n2;
-		struct list_head *pos2;
-		struct __prelim_ref *ref1;
+	list_for_each_entry(pos1, head, list) {
+		struct __prelim_ref *pos2 = pos1, *tmp;
 
-		ref1 = list_entry(pos1, struct __prelim_ref, list);
-
-		for (pos2 = pos1->next, n2 = pos2->next; pos2 != head;
-		     pos2 = n2, n2 = pos2->next) {
-			struct __prelim_ref *ref2;
-			struct __prelim_ref *xchg;
+		list_for_each_entry_safe_continue(pos2, tmp, head, list) {
+			struct __prelim_ref *ref1 = pos1, *ref2 = pos2;
 			struct extent_inode_elem *eie;
 
-			ref2 = list_entry(pos2, struct __prelim_ref, list);
-
 			if (!ref_for_same_block(ref1, ref2))
 				continue;
 			if (mode == 1) {
-				if (!ref1->parent && ref2->parent) {
-					xchg = ref1;
-					ref1 = ref2;
-					ref2 = xchg;
-				}
+				if (!ref1->parent && ref2->parent)
+					swap(ref1, ref2);
 			} else {
 				if (ref1->parent != ref2->parent)
 					continue;
@@ -1417,7 +1402,8 @@ char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
 			read_extent_buffer(eb, dest + bytes_left,
 					   name_off, name_len);
 		if (eb != eb_in) {
-			btrfs_tree_read_unlock_blocking(eb);
+			if (!path->skip_locking)
+				btrfs_tree_read_unlock_blocking(eb);
 			free_extent_buffer(eb);
 		}
 		ret = btrfs_find_item(fs_root, path, parent, 0,
@@ -1437,9 +1423,10 @@ char *btrfs_ref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path,
 		eb = path->nodes[0];
 		/* make sure we can use eb after releasing the path */
 		if (eb != eb_in) {
-			atomic_inc(&eb->refs);
-			btrfs_tree_read_lock(eb);
-			btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+			if (!path->skip_locking)
+				btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+			path->nodes[0] = NULL;
+			path->locks[0] = 0;
 		}
 		btrfs_release_path(path);
 		iref = btrfs_item_ptr(eb, slot, struct btrfs_inode_ref);