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author | Li Zefan <lizf@cn.fujitsu.com> | 2010-12-20 11:04:08 +0300 |
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committer | Li Zefan <lizf@cn.fujitsu.com> | 2010-12-23 03:49:17 +0300 |
commit | b83cc9693f39689490970c19f6c5b866f6719a70 (patch) | |
tree | b86d09884015fce195a4ac5ff1e8ec5f6ec00677 /fs/btrfs/ctree.h | |
parent | fa0d2b9bd717340e0bc4850a80ac0eb344e9a7fb (diff) | |
download | linux-b83cc9693f39689490970c19f6c5b866f6719a70.tar.xz |
Btrfs: Add readonly snapshots support
Usage:
Set BTRFS_SUBVOL_RDONLY of btrfs_ioctl_vol_arg_v2->flags, and call
ioctl(BTRFS_I0CTL_SNAP_CREATE_V2).
Implementation:
- Set readonly bit of btrfs_root_item->flags.
- Add readonly checks in btrfs_permission (inode_permission),
btrfs_setattr, btrfs_set/remove_xattr and some ioctls.
Changelog for v3:
- Eliminate btrfs_root->readonly, but check btrfs_root->root_item.flags.
- Rename BTRFS_ROOT_SNAP_RDONLY to BTRFS_ROOT_SUBVOL_RDONLY.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Diffstat (limited to 'fs/btrfs/ctree.h')
-rw-r--r-- | fs/btrfs/ctree.h | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index af52f6d7a4d8..4403e5643d43 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -597,6 +597,8 @@ struct btrfs_dir_item { u8 type; } __attribute__ ((__packed__)); +#define BTRFS_ROOT_SUBVOL_RDONLY (1ULL << 0) + struct btrfs_root_item { struct btrfs_inode_item inode; __le64 generation; @@ -1893,6 +1895,11 @@ BTRFS_SETGET_STACK_FUNCS(root_limit, struct btrfs_root_item, byte_limit, 64); BTRFS_SETGET_STACK_FUNCS(root_last_snapshot, struct btrfs_root_item, last_snapshot, 64); +static inline bool btrfs_root_readonly(struct btrfs_root *root) +{ + return root->root_item.flags & BTRFS_ROOT_SUBVOL_RDONLY; +} + /* struct btrfs_super_block */ BTRFS_SETGET_STACK_FUNCS(super_bytenr, struct btrfs_super_block, bytenr, 64); |