btrfs-progs: btrfstune: use on-stack path buffer in change_extents_uuid

We don't need to conserve stack space too much unlike kernel, also
remove one error condition.

Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 8 insertions, 11 deletions

diff --git a/btrfstune.c b/btrfstune.c
index 15dde908..0a22b98c 100644
--- a/btrfstune.c
+++ b/btrfstune.c
@@ -118,19 +118,16 @@ static int change_header_uuid(struct btrfs_root *root, struct extent_buffer *eb)
 static int change_extents_uuid(struct btrfs_fs_info *fs_info)
 {
 	struct btrfs_root *root = fs_info->extent_root;
-	struct btrfs_path *path;
+	struct btrfs_path path;
 	struct btrfs_key key = {0, 0, 0};
 	int ret = 0;
 
-	path = btrfs_alloc_path();
-	if (!path)
-		return -ENOMEM;
-
+	btrfs_init_path(&path);
 	/*
 	 * Here we don't use transaction as it will takes a lot of reserve
 	 * space, and that will make a near-full btrfs unable to change uuid
 	 */
-	ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+	ret = btrfs_search_slot(NULL, root, &key, &path, 0, 0);
 	if (ret < 0)
 		goto out;
 
@@ -140,13 +137,13 @@ static int change_extents_uuid(struct btrfs_fs_info *fs_info)
 		u64 flags;
 		u64 bytenr;
 
-		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
+		btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
 		if (key.type != BTRFS_EXTENT_ITEM_KEY &&
 		    key.type != BTRFS_METADATA_ITEM_KEY)
 			goto next;
-		ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
+		ei = btrfs_item_ptr(path.nodes[0], path.slots[0],
 				    struct btrfs_extent_item);
-		flags = btrfs_extent_flags(path->nodes[0], ei);
+		flags = btrfs_extent_flags(path.nodes[0], ei);
 		if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
 			goto next;
 
@@ -165,7 +162,7 @@ static int change_extents_uuid(struct btrfs_fs_info *fs_info)
 			goto out;
 		}
 next:
-		ret = btrfs_next_item(root, path);
+		ret = btrfs_next_item(root, &path);
 		if (ret < 0)
 			goto out;
 		if (ret > 0) {
@@ -175,7 +172,7 @@ next:
 	}
 
 out:
-	btrfs_free_path(path);
+	btrfs_release_path(&path);
 	return ret;
 }