From 8addcab0d06ae632573860bb1c3b054c0fa2dd52 Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Thu, 3 Jan 2019 15:32:21 +0800 Subject: [PATCH] btrfs-progs: Create uuid tree with proper contents Commit 2a496a5b8b74 ("btrfs-progs: mkfs: precreate the uuid tree") creates uuid tree at mkfs time. However it doesn't populate uuid tree correctly nor creates an empty root. It uses create_tree(), which just copies the content of fs root, containing a meaningless INODE_ITEM: v4.15 mkfs (no uuid tree creation) + kernel mount: uuid tree key (UUID_TREE ROOT_ITEM 0) leaf 30572544 items 1 free space 16250 generation 7 owner UUID_TREE leaf 30572544 flags 0x1(WRITTEN) backref revision 1 fs uuid 33ecddef-fc86-481a-93ce-846b01c11376 chunk uuid 9e58f646-b0da-43ca-9c7d-8bbe3e120246 item 0 key (0x92457c59d31491be UUID_KEY_SUBVOL 0xef908b5e79aa76a1) itemoff 16275 itemsize 8 subvol_id 5 v4.19.1 mkfs (incorrect one), no kernel mount: uuid tree key (UUID_TREE ROOT_ITEM 0) leaf 30507008 items 2 free space 16061 generation 4 owner UUID_TREE leaf 30507008 flags 0x1(WRITTEN) backref revision 1 fs uuid 162f5333-9b5d-4217-877c-ddaeaa79398e chunk uuid 7bc2c5c6-a6d2-4eec-a513-142b549c6541 item 0 key (256 INODE_ITEM 0) itemoff 16123 itemsize 160 generation 3 transid 0 size 0 nbytes 16384 block group 0 mode 40755 links 1 uid 0 gid 0 rdev 0 sequence 0 flags 0x0(none) item 1 key (256 INODE_REF 256) itemoff 16111 itemsize 12 index 0 namelen 2 name: .. This patchset will fix it by populuating uuid tree properly: (NOTE: due to tree-checker, kernel doesn't accept empty uuid tree, so we can only fix it by populating uuid tree correctly) With this patchset, no kernel mount: uuid tree key (UUID_TREE ROOT_ITEM 0) leaf 30507008 items 1 free space 16250 generation 4 owner UUID_TREE leaf 30507008 flags 0x1(WRITTEN) backref revision 1 fs uuid ae53079e-dbbc-409b-a565-5326c7b27731 chunk uuid b5fb1bea-f20d-4af1-80f8-6ca3f0038d67 item 0 key (0x334ba6b032d89c07 UUID_KEY_SUBVOL 0x86cde09cb78bcca0) itemoff 16275 itemsize 8 subvol_id 5 For kernel, except tree-checker needs an non-empty uuid tree, both of the above behavior won't cause problem, but it's always better to keep a good standardized behavior. Fixes: 2a496a5b8b74 ("btrfs-progs: mkfs: precreate the uuid tree") Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- mkfs/main.c | 59 +++++++++++++++++++++++------------------------------ 1 file changed, 26 insertions(+), 33 deletions(-) diff --git a/mkfs/main.c b/mkfs/main.c index 0a13e8d8..b442e6e4 100644 --- a/mkfs/main.c +++ b/mkfs/main.c @@ -310,38 +310,6 @@ static int create_raid_groups(struct btrfs_trans_handle *trans, return ret; } -static int create_tree(struct btrfs_trans_handle *trans, - struct btrfs_root *root, u64 objectid) -{ - struct btrfs_key location; - struct btrfs_root_item root_item; - struct extent_buffer *tmp; - u8 uuid[BTRFS_UUID_SIZE] = {0}; - int ret; - - ret = btrfs_copy_root(trans, root, root->node, &tmp, objectid); - if (ret) - return ret; - - memcpy(&root_item, &root->root_item, sizeof(root_item)); - btrfs_set_root_bytenr(&root_item, tmp->start); - btrfs_set_root_level(&root_item, btrfs_header_level(tmp)); - btrfs_set_root_generation(&root_item, trans->transid); - /* clear uuid and o/ctime of source tree */ - memcpy(root_item.uuid, uuid, BTRFS_UUID_SIZE); - btrfs_set_stack_timespec_sec(&root_item.otime, 0); - btrfs_set_stack_timespec_sec(&root_item.ctime, 0); - free_extent_buffer(tmp); - - location.objectid = objectid; - location.type = BTRFS_ROOT_ITEM_KEY; - location.offset = 0; - ret = btrfs_insert_root(trans, root->fs_info->tree_root, - &location, &root_item); - - return ret; -} - static void print_usage(int ret) { printf("Usage: mkfs.btrfs [options] dev [ dev ... ]\n"); @@ -777,6 +745,31 @@ out: return ret; } +static int create_uuid_tree(struct btrfs_trans_handle *trans) +{ + struct btrfs_fs_info *fs_info = trans->fs_info; + struct btrfs_root *root; + int ret = 0; + + ASSERT(fs_info->uuid_root == NULL); + root = btrfs_create_tree(trans, fs_info, BTRFS_UUID_TREE_OBJECTID); + if (IS_ERR(root)) { + ret = PTR_ERR(root); + goto out; + } + + add_root_to_dirty_list(root); + fs_info->uuid_root = root; + ret = btrfs_uuid_tree_add(trans, fs_info->fs_root->root_item.uuid, + BTRFS_UUID_KEY_SUBVOL, + fs_info->fs_root->root_key.objectid); + if (ret < 0) + btrfs_abort_transaction(trans, ret); + +out: + return ret; +} + int main(int argc, char **argv) { char *file; @@ -1277,7 +1270,7 @@ raid_groups: goto out; } - ret = create_tree(trans, root, BTRFS_UUID_TREE_OBJECTID); + ret = create_uuid_tree(trans); if (ret) warning( "unable to create uuid tree, will be created after mount: %d", ret);