btrfs: pass root owner to read_tree_block

In order to properly set the lockdep class of a newly allocated block we
need to know the owner of the block.  For non-refcounted trees this is
straightforward, we always know in advance what tree we're reading from.
For refcounted trees we don't necessarily know, however all refcounted
trees share the same lockdep class name, tree-<level>.

Fix all the callers of read_tree_block() to pass in the root objectid
we're using.  In places like relocation and backref we could probably
unconditionally use 0, but just in case use the root when we have it,
otherwise use 0 in the cases we don't have the root as it's going to be
a refcounted tree anyway.

This is a preparation patch for further changes.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 9 insertions, 5 deletions

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 012e66601270..763121380942 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -966,13 +966,14 @@ struct extent_buffer *btrfs_find_create_tree_block(
  * Read tree block at logical address @bytenr and do variant basic but critical
  * verification.
  *
+ * @owner_root:		the objectid of the root owner for this block.
  * @parent_transid:	expected transid of this tree block, skip check if 0
  * @level:		expected level, mandatory check
  * @first_key:		expected key in slot 0, skip check if NULL
  */
 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
-				      u64 parent_transid, int level,
-				      struct btrfs_key *first_key)
+				      u64 owner_root, u64 parent_transid,
+				      int level, struct btrfs_key *first_key)
 {
 	struct extent_buffer *buf = NULL;
 	int ret;
@@ -1295,7 +1296,7 @@ static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root,
 	level = btrfs_root_level(&root->root_item);
 	root->node = read_tree_block(fs_info,
 				     btrfs_root_bytenr(&root->root_item),
-				     generation, level, NULL);
+				     key->objectid, generation, level, NULL);
 	if (IS_ERR(root->node)) {
 		ret = PTR_ERR(root->node);
 		root->node = NULL;
@@ -2249,8 +2250,9 @@ static int btrfs_replay_log(struct btrfs_fs_info *fs_info,
 		return -ENOMEM;
 
 	log_tree_root->node = read_tree_block(fs_info, bytenr,
-					      fs_info->generation + 1,
-					      level, NULL);
+					      BTRFS_TREE_LOG_OBJECTID,
+					      fs_info->generation + 1, level,
+					      NULL);
 	if (IS_ERR(log_tree_root->node)) {
 		btrfs_warn(fs_info, "failed to read log tree");
 		ret = PTR_ERR(log_tree_root->node);
@@ -2636,6 +2638,7 @@ static int __cold init_tree_roots(struct btrfs_fs_info *fs_info)
 		generation = btrfs_super_generation(sb);
 		level = btrfs_super_root_level(sb);
 		tree_root->node = read_tree_block(fs_info, btrfs_super_root(sb),
+						  BTRFS_ROOT_TREE_OBJECTID,
 						  generation, level, NULL);
 		if (IS_ERR(tree_root->node)) {
 			handle_error = true;
@@ -3124,6 +3127,7 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device
 
 	chunk_root->node = read_tree_block(fs_info,
 					   btrfs_super_chunk_root(disk_super),
+					   BTRFS_CHUNK_TREE_OBJECTID,
 					   generation, level, NULL);
 	if (IS_ERR(chunk_root->node) ||
 	    !extent_buffer_uptodate(chunk_root->node)) {