Pull Ceph updates from Sage Weil:
"This has a mix of bug fixes and cleanups.
Alex's patch fixes a rare race in RBD. Ilya's patches fix an ENOENT
check when a second rbd image is mapped and a couple memory leaks.
Zheng fixes several issues with fragmented directories and multiple
MDSs. Josh fixes a spin/sleep issue, and Josh and Guangliang's
patches fix setting and unsetting RBD images read-only.
Naturally there are several other cleanups mixed in for good measure"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client: (23 commits)
rbd: only set disk to read-only once
rbd: move calls that may sleep out of spin lock range
rbd: add ioctl for rbd
ceph: use truncate_pagecache() instead of truncate_inode_pages()
ceph: include time stamp in every MDS request
rbd: fix ida/idr memory leak
rbd: use reference counts for image requests
rbd: fix osd_request memory leak in __rbd_dev_header_watch_sync()
rbd: make sure we have latest osdmap on 'rbd map'
libceph: add ceph_monc_wait_osdmap()
libceph: mon_get_version request infrastructure
libceph: recognize poolop requests in debugfs
ceph: refactor readpage_nounlock() to make the logic clearer
mds: check cap ID when handling cap export message
ceph: remember subtree root dirfrag's auth MDS
ceph: introduce ceph_fill_fragtree()
ceph: handle cap import atomically
ceph: pre-allocate ceph_cap struct for ceph_add_cap()
ceph: update inode fields according to issued caps
rbd: replace IS_ERR and PTR_ERR with PTR_ERR_OR_ZERO
...