btrfs: Don't generate UUID for non-fs tree

btrfs_create_tree() will unconditionally generate UUID for any root.
So for quota tree and data reloc tree created by kernel, they will have
unique UUIDs.

However UUID in root item is only referred by UUID tree, which only
records UUID for fs trees.  This makes unique UUIDs for quota/data reloc
tree meaningless.

Leave the UUID as zero for non-fs tree, making btrfs-debug-tree output
less confusing.

Reported-by: Misono Tomohiro <misono.tomohiro@jp.fujitsu.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Qu Wenruo 2017-10-31 14:08:16 +08:00 committed by David Sterba
parent 2c9973847f
commit 33d85fda13

View file

@ -1243,7 +1243,7 @@ struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
struct btrfs_root *root;
struct btrfs_key key;
int ret = 0;
uuid_le uuid;
uuid_le uuid = NULL_UUID_LE;
root = btrfs_alloc_root(fs_info, GFP_KERNEL);
if (!root)
@ -1284,7 +1284,8 @@ struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
btrfs_set_root_used(&root->root_item, leaf->len);
btrfs_set_root_last_snapshot(&root->root_item, 0);
btrfs_set_root_dirid(&root->root_item, 0);
uuid_le_gen(&uuid);
if (is_fstree(objectid))
uuid_le_gen(&uuid);
memcpy(root->root_item.uuid, uuid.b, BTRFS_UUID_SIZE);
root->root_item.drop_level = 0;