Pull ceph fixes from Sage Weil:
"There is an RBD fix for a crash due to the immutable bio changes, an
error path fix, and a locking fix in the recent redirect support"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
libceph: do not dereference a NULL bio pointer
libceph: take map_sem for read in handle_reply()
libceph: factor out logic from ceph_osdc_start_request()
libceph: fix error handling in ceph_osdc_init()