Pull ceph updates from Ilya Dryomov:
 "The main things are support for cephx v2 authentication protocol and
  basic support for rbd images within namespaces (myself).

  Also included are y2038 conversion patches from Arnd, a pile of
  miscellaneous fixes from Chengguang and Zheng's feature bit
  infrastructure for the filesystem"

* tag 'ceph-for-4.19-rc1' of git://github.com/ceph/ceph-client: (40 commits)
  ceph: don't drop message if it contains more data than expected
  ceph: support cephfs' own feature bits
  crush: fix using plain integer as NULL warning
  libceph: remove unnecessary non NULL check for request_key
  ceph: refactor error handling code in ceph_reserve_caps()
  ceph: refactor ceph_unreserve_caps()
  ceph: change to void return type for __do_request()
  ceph: compare fsc->max_file_size and inode->i_size for max file size limit
  ceph: add additional size check in ceph_setattr()
  ceph: add additional offset check in ceph_write_iter()
  ceph: add additional range check in ceph_fallocate()
  ceph: add new field max_file_size in ceph_fs_client
  libceph: weaken sizeof check in ceph_x_verify_authorizer_reply()
  libceph: check authorizer reply/challenge length before reading
  libceph: implement CEPHX_V2 calculation mode
  libceph: add authorizer challenge
  libceph: factor out encrypt_authorizer()
  libceph: factor out __ceph_x_decrypt()
  libceph: factor out __prepare_write_connect()
  libceph: store ceph_auth_handshake pointer in ceph_connection
  ...