ceph: quota: update MDS when max_bytes is approaching

ceph: quota: update MDS when max_bytes is approaching

BugLink: https://bugs.launchpad.net/bugs/1834235
When we're reaching the ceph.quota.max_bytes limit, i.e., when writing
more than 1/16th of the space left in a quota realm, update the MDS with
the new file size.

This mirrors the fuse-client approach with commit 122c50315ed1 ("client:
Inform mds file size when approaching quota limit"), in the ceph git tree.

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
(cherry picked from commit 1ab302a0cb1455631646aa66b7fc02afd617ea4f)
Signed-off-by: Connor Kuehl <connor.kuehl@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>