Btrfs: remove mnt_want_write call in btrfs_mksubvol
We got a recursive lock in mksubvol because the caller already held
a lock. I think we got into this due to a merge error. Commit a874a63
removed the mnt_want_write call from btrfs_mksubvol and added a
replacement call to mnt_want_write_file in btrfs_ioctl_snap_create_transid.
Commit e7848683 however tried to move all calls to mnt_want_write above
i_mutex. So somewhere while merging this, it got mixed up. The
solution is to remove the mnt_want_write call completely from
mksubvol.
Reported-by: David Sterba <dave@jikos.cz>
Signed-off-by: Alexander Block <ablock84@googlemail.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index bc2f6ff..7bb7556 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -664,10 +664,6 @@
struct dentry *dentry;
int error;
- error = mnt_want_write(parent->mnt);
- if (error)
- return error;
-
mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
dentry = lookup_one_len(name, parent->dentry, namelen);
@@ -703,7 +699,6 @@
dput(dentry);
out_unlock:
mutex_unlock(&dir->i_mutex);
- mnt_drop_write(parent->mnt);
return error;
}
