Merge tag 'ceph-for-5.7-rc1' of git://github.com/ceph/ceph-client

Pull ceph updates from Ilya Dryomov:
 "The main items are:

   - support for asynchronous create and unlink (Jeff Layton).

     Creates and unlinks are satisfied locally, without waiting for a
     reply from the MDS, provided the client has been granted
     appropriate caps (new in v15.y.z ("Octopus") release). This can be
     a big help for metadata heavy workloads such as tar and rsync.
     Opt-in with the new nowsync mount option.

   - multiple blk-mq queues for rbd (Hannes Reinecke and myself).

     When the driver was converted to blk-mq, we settled on a single
     blk-mq queue because of a global lock in libceph and some other
     technical debt. These have since been addressed, so allocate a
     queue per CPU to enhance parallelism.

   - don't hold onto caps that aren't actually needed (Zheng Yan).

     This has been our long-standing behavior, but it causes issues with
     some active/standby applications (synchronous I/O, stalls if the
     standby goes down, etc).

   - .snap directory timestamps consistent with ceph-fuse (Luis
     Henriques)"

* tag 'ceph-for-5.7-rc1' of git://github.com/ceph/ceph-client: (49 commits)
  ceph: fix snapshot directory timestamps
  ceph: wait for async creating inode before requesting new max size
  ceph: don't skip updating wanted caps when cap is stale
  ceph: request new max size only when there is auth cap
  ceph: cleanup return error of try_get_cap_refs()
  ceph: return ceph_mdsc_do_request() errors from __get_parent()
  ceph: check all mds' caps after page writeback
  ceph: update i_requested_max_size only when sending cap msg to auth mds
  ceph: simplify calling of ceph_get_fmode()
  ceph: remove delay check logic from ceph_check_caps()
  ceph: consider inode's last read/write when calculating wanted caps
  ceph: always renew caps if mds_wanted is insufficient
  ceph: update dentry lease for async create
  ceph: attempt to do async create when possible
  ceph: cache layout in parent dir on first sync create
  ceph: add new MDS req field to hold delegated inode number
  ceph: decode interval_sets for delegated inos
  ceph: make ceph_fill_inode non-static
  ceph: perform asynchronous unlink if we have sufficient caps
  ceph: don't take refs to want mask unless we have all bits
  ...

diff --cc Documentation/filesystems/ceph.rst
index b46a7218248fa32508864e83aadbf0dd80bb4f87,0000000000000000000000000000000000000000..0aa70750df0fe02142cf25a1319ada39093baeb8
mode 100644,000000..100644
--- 1/Documentation/filesystems/ceph.rst
--- /dev/null
+++ b/Documentation/filesystems/ceph.rst
@@@ -1,190 -1,0 +1,190 @@@
-       Specify the maximum write size in bytes.  Default: 16 MB.
 +.. SPDX-License-Identifier: GPL-2.0
 +
 +============================
 +Ceph Distributed File System
 +============================
 +
 +Ceph is a distributed network file system designed to provide good
 +performance, reliability, and scalability.
 +
 +Basic features include:
 +
 + * POSIX semantics
 + * Seamless scaling from 1 to many thousands of nodes
 + * High availability and reliability.  No single point of failure.
 + * N-way replication of data across storage nodes
 + * Fast recovery from node failures
 + * Automatic rebalancing of data on node addition/removal
 + * Easy deployment: most FS components are userspace daemons
 +
 +Also,
 +
 + * Flexible snapshots (on any directory)
 + * Recursive accounting (nested files, directories, bytes)
 +
 +In contrast to cluster filesystems like GFS, OCFS2, and GPFS that rely
 +on symmetric access by all clients to shared block devices, Ceph
 +separates data and metadata management into independent server
 +clusters, similar to Lustre.  Unlike Lustre, however, metadata and
 +storage nodes run entirely as user space daemons.  File data is striped
 +across storage nodes in large chunks to distribute workload and
 +facilitate high throughputs.  When storage nodes fail, data is
 +re-replicated in a distributed fashion by the storage nodes themselves
 +(with some minimal coordination from a cluster monitor), making the
 +system extremely efficient and scalable.
 +
 +Metadata servers effectively form a large, consistent, distributed
 +in-memory cache above the file namespace that is extremely scalable,
 +dynamically redistributes metadata in response to workload changes,
 +and can tolerate arbitrary (well, non-Byzantine) node failures.  The
 +metadata server takes a somewhat unconventional approach to metadata
 +storage to significantly improve performance for common workloads.  In
 +particular, inodes with only a single link are embedded in
 +directories, allowing entire directories of dentries and inodes to be
 +loaded into its cache with a single I/O operation.  The contents of
 +extremely large directories can be fragmented and managed by
 +independent metadata servers, allowing scalable concurrent access.
 +
 +The system offers automatic data rebalancing/migration when scaling
 +from a small cluster of just a few nodes to many hundreds, without
 +requiring an administrator carve the data set into static volumes or
 +go through the tedious process of migrating data between servers.
 +When the file system approaches full, new nodes can be easily added
 +and things will "just work."
 +
 +Ceph includes flexible snapshot mechanism that allows a user to create
 +a snapshot on any subdirectory (and its nested contents) in the
 +system.  Snapshot creation and deletion are as simple as 'mkdir
 +.snap/foo' and 'rmdir .snap/foo'.
 +
 +Ceph also provides some recursive accounting on directories for nested
 +files and bytes.  That is, a 'getfattr -d foo' on any directory in the
 +system will reveal the total number of nested regular files and
 +subdirectories, and a summation of all nested file sizes.  This makes
 +the identification of large disk space consumers relatively quick, as
 +no 'du' or similar recursive scan of the file system is required.
 +
 +Finally, Ceph also allows quotas to be set on any directory in the system.
 +The quota can restrict the number of bytes or the number of files stored
 +beneath that point in the directory hierarchy.  Quotas can be set using
 +extended attributes 'ceph.quota.max_files' and 'ceph.quota.max_bytes', eg::
 +
 + setfattr -n ceph.quota.max_bytes -v 100000000 /some/dir
 + getfattr -n ceph.quota.max_bytes /some/dir
 +
 +A limitation of the current quotas implementation is that it relies on the
 +cooperation of the client mounting the file system to stop writers when a
 +limit is reached.  A modified or adversarial client cannot be prevented
 +from writing as much data as it needs.
 +
 +Mount Syntax
 +============
 +
 +The basic mount syntax is::
 +
 + # mount -t ceph monip[:port][,monip2[:port]...]:/[subdir] mnt
 +
 +You only need to specify a single monitor, as the client will get the
 +full list when it connects.  (However, if the monitor you specify
 +happens to be down, the mount won't succeed.)  The port can be left
 +off if the monitor is using the default.  So if the monitor is at
 +1.2.3.4::
 +
 + # mount -t ceph 1.2.3.4:/ /mnt/ceph
 +
 +is sufficient.  If /sbin/mount.ceph is installed, a hostname can be
 +used instead of an IP address.
 +
 +
 +
 +Mount Options
 +=============
 +
 +  ip=A.B.C.D[:N]
 +      Specify the IP and/or port the client should bind to locally.
 +      There is normally not much reason to do this.  If the IP is not
 +      specified, the client's IP address is determined by looking at the
 +      address its connection to the monitor originates from.
 +
 +  wsize=X
-       Specify the maximum read size in bytes.  Default: 16 MB.
++      Specify the maximum write size in bytes.  Default: 64 MB.
 +
 +  rsize=X
-       of a non-responsive Ceph file system.  The default is 30
++      Specify the maximum read size in bytes.  Default: 64 MB.
 +
 +  rasize=X
 +      Specify the maximum readahead size in bytes.  Default: 8 MB.
 +
 +  mount_timeout=X
 +      Specify the timeout value for mount (in seconds), in the case
++      of a non-responsive Ceph file system.  The default is 60
 +      seconds.
 +
 +  caps_max=X
 +      Specify the maximum number of caps to hold. Unused caps are released
 +      when number of caps exceeds the limit. The default is 0 (no limit)
 +
 +  rbytes
 +      When stat() is called on a directory, set st_size to 'rbytes',
 +      the summation of file sizes over all files nested beneath that
 +      directory.  This is the default.
 +
 +  norbytes
 +      When stat() is called on a directory, set st_size to the
 +      number of entries in that directory.
 +
 +  nocrc
 +      Disable CRC32C calculation for data writes.  If set, the storage node
 +      must rely on TCP's error correction to detect data corruption
 +      in the data payload.
 +
 +  dcache
 +        Use the dcache contents to perform negative lookups and
 +        readdir when the client has the entire directory contents in
 +        its cache.  (This does not change correctness; the client uses
 +        cached metadata only when a lease or capability ensures it is
 +        valid.)
 +
 +  nodcache
 +        Do not use the dcache as above.  This avoids a significant amount of
 +        complex code, sacrificing performance without affecting correctness,
 +        and is useful for tracking down bugs.
 +
 +  noasyncreaddir
 +      Do not use the dcache as above for readdir.
 +
 +  noquotadf
 +        Report overall filesystem usage in statfs instead of using the root
 +        directory quota.
 +
 +  nocopyfrom
 +        Don't use the RADOS 'copy-from' operation to perform remote object
 +        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
 +================
 +
 +For more information on Ceph, see the home page at
 +      https://ceph.com/
 +
 +The Linux kernel client source tree is available at
 +      - https://github.com/ceph/ceph-client.git
 +      - git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client.git
 +
 +and the source for the full system is at
 +      https://github.com/ceph/ceph.git