Pull Ceph updates from Sage Weil:
 "There is the long-awaited discard support for RBD (Guangliang Zhao,
  Josh Durgin), a pile of RBD bug fixes that didn't belong in late -rc's
  (Ilya Dryomov, Li RongQing), a pile of fs/ceph bug fixes and
  performance and debugging improvements (Yan, Zheng, John Spray), and a
  smattering of cleanups (Chao Yu, Fabian Frederick, Joe Perches)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (40 commits)
  ceph: fix divide-by-zero in __validate_layout()
  rbd: rbd workqueues need a resque worker
  libceph: ceph-msgr workqueue needs a resque worker
  ceph: fix bool assignments
  libceph: separate multiple ops with commas in debugfs output
  libceph: sync osd op definitions in rados.h
  libceph: remove redundant declaration
  ceph: additional debugfs output
  ceph: export ceph_session_state_name function
  ceph: include the initial ACL in create/mkdir/mknod MDS requests
  ceph: use pagelist to present MDS request data
  libceph: reference counting pagelist
  ceph: fix llistxattr on symlink
  ceph: send client metadata to MDS
  ceph: remove redundant code for max file size verification
  ceph: remove redundant io_iter_advance()
  ceph: move ceph_find_inode() outside the s_mutex
  ceph: request xattrs if xattr_version is zero
  rbd: set the remaining discard properties to enable support
  rbd: use helpers to handle discard for layered images correctly
  ...