Merge tag 'ceph-for-5.4-rc1' of git://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "The highlights are:

   - automatic recovery of a blacklisted filesystem session (Zheng Yan).
     This is disabled by default and can be enabled by mounting with the
     new "recover_session=clean" option.

   - serialize buffered reads and O_DIRECT writes (Jeff Layton). Care is
     taken to avoid serializing O_DIRECT reads and writes with each
     other, this is based on the exclusion scheme from NFS.

   - handle large osdmaps better in the face of fragmented memory
     (myself)

   - don't limit what security.* xattrs can be get or set (Jeff Layton).
     We were overly restrictive here, unnecessarily preventing things
     like file capability sets stored in security.capability from
     working.

   - allow copy_file_range() within the same inode and across different
     filesystems within the same cluster (Luis Henriques)"

* tag 'ceph-for-5.4-rc1' of git://github.com/ceph/ceph-client: (41 commits)
  ceph: call ceph_mdsc_destroy from destroy_fs_client
  libceph: use ceph_kvmalloc() for osdmap arrays
  libceph: avoid a __vmalloc() deadlock in ceph_kvmalloc()
  ceph: allow object copies across different filesystems in the same cluster
  ceph: include ceph_debug.h in cache.c
  ceph: move static keyword to the front of declarations
  rbd: pull rbd_img_request_create() dout out into the callers
  ceph: reconnect connection if session hang in opening state
  libceph: drop unused con parameter of calc_target()
  ceph: use release_pages() directly
  rbd: fix response length parameter for encoded strings
  ceph: allow arbitrary security.* xattrs
  ceph: only set CEPH_I_SEC_INITED if we got a MAC label
  ceph: turn ceph_security_invalidate_secctx into static inline
  ceph: add buffered/direct exclusionary locking for reads and writes
  libceph: handle OSD op ceph_pagelist_append() errors
  ceph: don't return a value from void function
  ceph: don't freeze during write page faults
  ceph: update the mtime when truncating up
  ceph: fix indentation in __get_snap_name()
  ...

Documentation/filesystems/ceph.txt

@@ -158,6 +158,20 @@ Mount Options
         copies.  Currently, it's only used in copy_file_range, which will revert
         to the default VFS implementation if this option is used.
 
+  recover_session=<no|clean>
+	Set auto reconnect mode in the case where the client is blacklisted. The
+	available modes are "no" and "clean". The default is "no".
+
+	* no: never attempt to reconnect when client detects that it has been
+	blacklisted. Operations will generally fail after being blacklisted.
+
+	* clean: client reconnects to the ceph cluster automatically when it
+	detects that it has been blacklisted. During reconnect, client drops
+	dirty data/metadata, invalidates page caches and writable file handles.
+	After reconnect, file locks become stale because the MDS loses track
+	of them. If an inode contains any stale file locks, read/write on the
+	inode is not allowed until applications release all stale file locks.
+
 More Information
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