From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from victor.provo.novell.com ([137.65.250.26]:53755 "EHLO prv3-mh.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751610AbdJaGIh (ORCPT ); Tue, 31 Oct 2017 02:08:37 -0400 From: Qu Wenruo To: linux-btrfs@vger.kernel.org Cc: dsterba@suse.cz Subject: [PATCH] btrfs: Don't generate UUID for non-fs tree Date: Tue, 31 Oct 2017 14:08:16 +0800 Message-Id: <20171031060816.683-1-wqu@suse.com> Sender: linux-btrfs-owner@vger.kernel.org List-ID: 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 Signed-off-by: Qu Wenruo --- fs/btrfs/disk-io.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index dfdab849037b..d85e04a675fe 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1403,7 +1403,7 @@ 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 = { 0 }; root = btrfs_alloc_root(fs_info, GFP_KERNEL); if (!root) @@ -1444,7 +1444,8 @@ 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; -- 2.14.3