doc/cephfs: add note about CephFS extended attributes and getfattr

Supersedes https://github.com/ceph/ceph/pull/50060

Add a note on the fact that CephFS extended attributes are not printed
by "getfattr /some/cephfs/dir/ -d -m -" even when the CephFS directory
has some extended attributes set on it.

https://lists.ceph.io/hyperkitty/list/ceph-users@ceph.io/thread/6ENI42ZMHTTP2OONBRD7FDP7LQBC4P2E/

Primary Author: Rishabh Dave <ridave@redhat.com>
Co-author: Anthony D'Atri <anthony.datri@gmail.com>
Signed-off-by: Zac Dover <zac.dover@proton.me>

diff --git a/doc/cephfs/quota.rst b/doc/cephfs/quota.rst
index 777298f911cd116f2646b0b2ee7053cb2a83dc3d..a13795159e9dcd5c1b17b313462de780d0a1d91e 100644 (file)
--- a/doc/cephfs/quota.rst
+++ b/doc/cephfs/quota.rst
@@ -86,3 +86,11 @@ To remove a quota::
 
   setfattr -n ceph.quota.max_bytes -v 0 /some/dir
   setfattr -n ceph.quota.max_files -v 0 /some/dir
+
+
+.. note:: In cases where CephFS extended attributes are set on a CephFS
+   directory (for example, ``/some/dir``), running ``getfattr /some/dir -d -m
+   -`` will not print those CephFS extended attributes. This is because CephFS
+   kernel and FUSE clients hide this information from the ``listxattr(2)``
+   system call. You can access a specific CephFS extended attribute by running
+   ``getfattr /some/dir -n ceph.<some-xattr>`` instead.