diff options
| author | Li Zefan <lizf@cn.fujitsu.com> | 2011-03-28 02:01:25 +0000 |
|---|---|---|
| committer | Chris Mason <chris.mason@oracle.com> | 2011-04-05 01:20:24 -0400 |
| commit | 08fe4db170b4193603d9d31f40ebaf652d07ac9c (patch) | |
| tree | 2d0d2abe40b77266600653e399d4973a679716a9 /fs/btrfs/ctree.h | |
| parent | adae52b94e18afa1f84fab67df2a8a872c2f5533 (diff) | |
Btrfs: Fix uninitialized root flags for subvolumes
root_item->flags and root_item->byte_limit are not initialized when
a subvolume is created. This bug is not revealed until we added
readonly snapshot support - now you mount a btrfs filesystem and you
may find the subvolumes in it are readonly.
To work around this problem, we steal a bit from root_item->inode_item->flags,
and use it to indicate if those fields have been properly initialized.
When we read a tree root from disk, we check if the bit is set, and if
not we'll set the flag and initialize the two fields of the root item.
Reported-by: Andreas Philipp <philipp.andreas@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Tested-by: Andreas Philipp <philipp.andreas@gmail.com>
cc: stable@kernel.org
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Diffstat (limited to 'fs/btrfs/ctree.h')
| -rw-r--r-- | fs/btrfs/ctree.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index d47ce8307854..3458b5725540 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1284,6 +1284,8 @@ struct btrfs_root { #define BTRFS_INODE_DIRSYNC (1 << 10) #define BTRFS_INODE_COMPRESS (1 << 11) +#define BTRFS_INODE_ROOT_ITEM_INIT (1 << 31) + /* some macros to generate set/get funcs for the struct fields. This * assumes there is a lefoo_to_cpu for every type, so lets make a simple * one for u8: @@ -2359,6 +2361,8 @@ int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid); int btrfs_find_orphan_roots(struct btrfs_root *tree_root); int btrfs_set_root_node(struct btrfs_root_item *item, struct extent_buffer *node); +void btrfs_check_and_init_root_item(struct btrfs_root_item *item); + /* dir-item.c */ int btrfs_insert_dir_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, const char *name, |