ceph: pass unhandled ceph.* setxattrs through to MDS

If we do not specifically understand a setxattr on a ceph.* virtual
xattr, send it through to the MDS.  This allows us to implement new
functionality via the MDS without direct support on the client side.

Signed-off-by: Sage Weil <sage@inktank.com>
Reviewed-by: Sam Lang <sam.lang@inktank.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 43063d0dee8f..edc47de77fed 100644
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -777,6 +777,10 @@ int ceph_setxattr(struct dentry *dentry, const char *name,
         if (vxattr && vxattr->readonly)
                 return -EOPNOTSUPP;
 
+        /* pass any unhandled ceph.* xattrs through to the MDS */
+        if (!strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN))
+                goto do_sync_unlocked;
+
         /* preallocate memory for xattr name, value, index node */
         err = -ENOMEM;
         newname = kmemdup(name, name_len + 1, GFP_NOFS);
@@ -833,6 +837,7 @@ retry:
 
 do_sync:
         spin_unlock(&ci->i_ceph_lock);
+do_sync_unlocked:
         err = ceph_sync_setxattr(dentry, name, value, size, flags);
 out:
         kfree(newname);