This patchset can be fetched from github: https://github.com/adam900710/btrfs-progs/tree/uuid_tree_support Which is based on v4.19.1 tag. Commit 2a496a5b8b74 ("btrfs-progs: mkfs: precreate the uuid tree") creates uuid tree at mkfs time. However it doesn't populate uuid tree correctly nor just create an empty root. It uses create_tree(), which just copies the content of fs root, containing 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, as kernel tree checker now doesn't accept empty uuid tree. w/ 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 Qu Wenruo (3): btrfs-progs: uuid: Port kernel btrfs_uuid_tree_lookup() btrfs-progs: uuid: Port btrfs_uuid_tree_add() function btrfs-progs: Create uuid tree with proper contents ctree.h | 7 ++- disk-io.c | 4 ++ mkfs/common.c | 103 ++++++++++++++++++++++++++++++++++++++ mkfs/common.h | 3 ++ mkfs/main.c | 36 +------------ uuid-tree.c | 136 +++++++++++++++++++++++++++++++++++++++++++++++++- 6 files changed, 252 insertions(+), 37 deletions(-) -- 2.20.1
