diff options
| author | Li Zefan <lizf@cn.fujitsu.com> | 2010-12-20 16:04:08 +0800 |
|---|---|---|
| committer | Li Zefan <lizf@cn.fujitsu.com> | 2010-12-23 08:49:17 +0800 |
| commit | b83cc9693f39689490970c19f6c5b866f6719a70 (patch) | |
| tree | b86d09884015fce195a4ac5ff1e8ec5f6ec00677 /fs/btrfs/inode.c | |
| parent | fa0d2b9bd717340e0bc4850a80ac0eb344e9a7fb (diff) | |
| download | kernel_goldelico_gta04-b83cc9693f39689490970c19f6c5b866f6719a70.zip kernel_goldelico_gta04-b83cc9693f39689490970c19f6c5b866f6719a70.tar.gz kernel_goldelico_gta04-b83cc9693f39689490970c19f6c5b866f6719a70.tar.bz2 | |
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/inode.c')
| -rw-r--r-- | fs/btrfs/inode.c | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 5f91944..956f1eb 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3671,8 +3671,12 @@ static int btrfs_setattr_size(struct inode *inode, struct iattr *attr) static int btrfs_setattr(struct dentry *dentry, struct iattr *attr) { struct inode *inode = dentry->d_inode; + struct btrfs_root *root = BTRFS_I(inode)->root; int err; + if (btrfs_root_readonly(root)) + return -EROFS; + err = inode_change_ok(inode, attr); if (err) return err; @@ -7206,6 +7210,10 @@ static int btrfs_set_page_dirty(struct page *page) static int btrfs_permission(struct inode *inode, int mask) { + struct btrfs_root *root = BTRFS_I(inode)->root; + + if (btrfs_root_readonly(root) && (mask & MAY_WRITE)) + return -EROFS; if ((BTRFS_I(inode)->flags & BTRFS_INODE_READONLY) && (mask & MAY_WRITE)) return -EACCES; return generic_permission(inode, mask, btrfs_check_acl); |