Commit aa60cfc3f7ee broke the error handling in these functions such
that they don't handle non-ENOENT errors from ceph_mdsc_do_request
properly.

Move the checking of -ENOENT out of ceph_handle_snapdir and into the
callers, and if we get a different error, return it immediately.

Fixes: aa60cfc3f7ee ("ceph: don't use d_add in ceph_handle_snapdir")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

...and add a lockdep assertion for it to ceph_fill_inode().

Cc: stable@vger.kernel.org # v5.7+
Fixes: 9a8d03ca2e2c3 ("ceph: attempt to do async create when possible")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Pull ceph updates from Ilya Dryomov:
 "Notable items here are

   - a series to take advantage of David Howells' netfs helper library
     from Jeff

   - three new filesystem client metrics from Xiubo

   - ceph.dir.rsnaps vxattr from Yanhu

   - two auth-related fixes from myself, marked for stable.

  Interspersed is a smattering of assorted fixes and cleanups across the
  filesystem"

* tag 'ceph-for-5.13-rc1' of git://github.com/ceph/ceph-client: (24 commits)
  libceph: allow addrvecs with a single NONE/blank address
  libceph: don't set global_id until we get an auth ticket
  libceph: bump CephXAuthenticate encoding version
  ceph: don't allow access to MDS-private inodes
  ceph: fix up some bare fetches of i_size
  ceph: convert some PAGE_SIZE invocations to thp_size()
  ceph: support getting ceph.dir.rsnaps vxattr
  ceph: drop pinned_page parameter from ceph_get_caps
  ceph: fix inode leak on getattr error in __fh_to_dentry
  ceph: only check pool permissions for regular files
  ceph: send opened files/pinned caps/opened inodes metrics to MDS daemon
  ceph: avoid counting the same request twice or more
  ceph: rename the metric helpers
  ceph: fix kerneldoc copypasta over ceph_start_io_direct
  ceph: use attach/detach_page_private for tracking snap context
  ceph: don't use d_add in ceph_handle_snapdir
  ceph: don't clobber i_snap_caps on non-I_NEW inode
  ceph: fix fall-through warnings for Clang
  ceph: convert ceph_readpages to ceph_readahead
  ceph: convert ceph_write_begin to netfs_write_begin
  ...

The MDS reserves a set of inodes for its own usage, and these should
never be accessible to clients. Add a new helper to vet a proposed
inode number against that range, and complain loudly and refuse to
create or look it up if it's in it.

Also, ensure that the MDS doesn't try to delegate inodes that are in
that range or lower. Print a warning if it does, and don't save the
range in the xarray.

URL: https://tracker.ceph.com/issues/49922
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

We need to use i_size_read(), which properly handles the torn read
case on 32-bit arches.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Start preparing to allow the use of THPs in the pagecache with ceph by
making it use thp_size() in lieu of PAGE_SIZE in the appropriate places.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Add support for grabbing the rsnaps value out of the inode info in
traces, and exposing that via ceph.dir.rsnaps xattr.

Signed-off-by: Yanhu Cao <gmayyyha@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

All of the existing callers that don't set this to NULL just drop the
page reference at some arbitrary point later in processing. There's no
point in keeping a page reference that we don't use, so just drop the
reference immediately after checking the Uptodate flag.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

Fixes: 878dabb64117 ("ceph: don't return -ESTALE if there's still an open file")
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

There is no need to do a ceph_pool_perm_check() on anything that isn't a
regular file, as the MDS is what handles talking to the OSD in those
cases. Just return 0 if it's not a regular file.

Reported-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>