Hi
On 04/06/2011 11:34 AM, Zhong, Xin wrote:
> We create two subvolumes (meego_root and meego_home) in
> btrfs root directory. And set meego_root as default mount
> subvolume. After we remount btrfs, meego_root is mounted
> to top directory by default. Then if we create a directory with
> the same name as meego_home, we can mount meego_home subvolume
> sucessfully (subvol=meego_home). But this is incorrect. What we
> do in this mount point will not change anything in meego_home
> subvolume. The problem is when default mount subvolume is set to
> meego_root, we search meego_home in meego_root. But if we find a
> directory with the same name, we will treat it as subvolume. So
> the solution is to check if what we find is really a subvolume.
I think that this a bug, so a warning should be raised. We had a lot of
problem because "btrfsctl -s " did the same thing: if we referred to a
directory, they snapshot the directory's subvolume and the user didn't
understood what happened.
Personally I prefer that in case a wrong option the kernel raises a
warning and stops, not that it makes a choice about which default is
more reasonable.
Reagrds
G.Baroncelli
>
> Signed-off-by: Zhong, Xin <xin.zh...@intel.com>
> ---
> fs/btrfs/super.c | 4 +++-
> 1 files changed, 3 insertions(+), 1 deletions(-)
>
> diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
> index b85fe78..66a76b7 100644
> --- a/fs/btrfs/super.c
> +++ b/fs/btrfs/super.c
> @@ -823,7 +823,9 @@ static int btrfs_get_sb(struct file_system_type *fs_type,
> int flags,
> error = PTR_ERR(new_root);
> goto error_free_subvol_name;
> }
> - if (!new_root->d_inode) {
> + if (!new_root->d_inode ||
> + /* new_root is a directory, not subvolume */
> + new_root->d_inode->i_ino != BTRFS_FIRST_FREE_OBJECTID) {
> dput(root);
> dput(new_root);
> deactivate_locked_super(s);
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
