It turns out that the current version of gfs2_metadata_walker suffers
from multiple problems that can cause gfs2_hole_size to report an
incorrect size.  This will confuse fiemap as well as lseek with the
SEEK_DATA flag.

Fix that by changing gfs2_hole_walker to compute the metapath to the
first data block after the hole (if any), and compute the hole size
based on that.

Fixes xfstest generic/490.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Cc: stable@vger.kernel.org # v4.18+

With the recent iomap write page reclaim deadlock fix, it turns out that the
GLF_DIRTY flag isn't always set when it needs to be anymore: previously, this
happened as a side effect of always adding the inode buffer head to the current
transaction with gfs2_trans_add_meta, but this isn't happening consistently
anymore.  Fix by removing an additional unnecessary gfs2_trans_add_meta call
and by setting the GLF_DIRTY flag in gfs2_iomap_end.

(The GLF_DIRTY flag causes inode_go_sync to flush the transaction log when
syncing out the glock of that inode.  When the flag isn't set, inode_go_sync
will skip inodes, including ones with an i_state of I_DIRTY_PAGES, which will
lead to cluster incoherency.)

In addition, in gfs2_iomap_page_done, if the metadata has changed, mark the
inode as I_DIRTY_DATASYNC to have the inode added to the current transaction:
we don't expect metadata to change here, but let's err on the safe side.

Fixes: d0a22a4b03b8 ("gfs2: Fix iomap write page reclaim deadlock");
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Pull common SETFLAGS/FSSETXATTR parameter checking from Darrick Wong:
 "Here's a patch series that sets up common parameter checking functions
  for the FS_IOC_SETFLAGS and FS_IOC_FSSETXATTR ioctl implementations.

  The goal here is to reduce the amount of behaviorial variance between
  the filesystems where those ioctls originated (ext2 and XFS,
  respectively) and everybody else.

   - Standardize parameter checking for the SETFLAGS and FSSETXATTR
     ioctls (which were the file attribute setters for ext4 and xfs and
     have now been hoisted to the vfs)

   - Only allow the DAX flag to be set on files and directories"

* tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  vfs: only allow FSSETXATTR to set DAX flag on files and dirs
  vfs: teach vfs_ioc_fssetxattr_check to check extent size hints
  vfs: teach vfs_ioc_fssetxattr_check to check project id info
  vfs: create a generic checking function for FS_IOC_FSSETXATTR
  vfs: create a generic checking and prep function for FS_IOC_SETFLAGS

Pull driver core and debugfs updates from Greg KH:
 "Here is the "big" driver core and debugfs changes for 5.3-rc1

  It's a lot of different patches, all across the tree due to some api
  changes and lots of debugfs cleanups.

  Other than the debugfs cleanups, in this set of changes we have:

   - bus iteration function cleanups

   - scripts/get_abi.pl tool to display and parse Documentation/ABI
     entries in a simple way

   - cleanups to Documenatation/ABI/ entries to make them parse easier
     due to typos and other minor things

   - default_attrs use for some ktype users

   - driver model documentation file conversions to .rst

   - compressed firmware file loading

   - deferred probe fixes

  All of these have been in linux-next for a while, with a bunch of
  merge issues that Stephen has been patient with me for"

* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
  debugfs: make error message a bit more verbose
  orangefs: fix build warning from debugfs cleanup patch
  ubifs: fix build warning after debugfs cleanup patch
  driver: core: Allow subsystems to continue deferring probe
  drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
  arch_topology: Remove error messages on out-of-memory conditions
  lib: notifier-error-inject: no need to check return value of debugfs_create functions
  swiotlb: no need to check return value of debugfs_create functions
  ceph: no need to check return value of debugfs_create functions
  sunrpc: no need to check return value of debugfs_create functions
  ubifs: no need to check return value of debugfs_create functions
  orangefs: no need to check return value of debugfs_create functions
  nfsd: no need to check return value of debugfs_create functions
  lib: 842: no need to check return value of debugfs_create functions
  debugfs: provide pr_fmt() macro
  debugfs: log errors when something goes wrong
  drivers: s390/cio: Fix compilation warning about const qualifiers
  drivers: Add generic helper to match by of_node
  driver_find_device: Unify the match function with class_find_device()
  bus_find_device: Unify the match callback with class_find_device
  ...

Pull gfs2 updates from Andreas Gruenbacher:
 "Some relatively minor changes for gfs2:

   - An initial batch of obvious cleanups and fixes from Bob's recovery
     patch queue.

   - Two iomap conversion patches and some cleanups from Christoph
     Hellwig.

   - A cosmetic cleanup from Kefeng Wang (Huawei).

   - Another minor fix and cleanup by me"

* tag 'gfs2-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Remove unused gfs2_iomap_alloc argument
  gfs2: don't use buffer_heads in gfs2_allocate_page_backing
  gfs2: use iomap_bmap instead of generic_block_bmap
  gfs2: mark stuffed_readpage static
  gfs2: merge gfs2_writepage_common into gfs2_writepage
  gfs2: merge gfs2_writeback_aops and gfs2_ordered_aops
  gfs2: remove the unused gfs2_stuffed_write_end function
  gfs2: use page_offset in gfs2_page_mkwrite
  gfs2: replace more printk with calls to fs_info and friends
  gfs2: dump fsid when dumping glock problems
  gfs2: simplify gfs2_freeze by removing case
  gfs2: Rename SDF_SHUTDOWN to SDF_WITHDRAWN
  gfs2: Warn when a journal replay overwrites a rgrp with buffers
  gfs2: log which portion of the journal is replayed
  gfs2: eliminate tr_num_revoke_rm
  gfs2: kthread and remount improvements
  gfs2: Use IS_ERR_OR_NULL
  gfs2: Clean up freeing struct gfs2_sbd

Pull iomap updates from Darrick Wong:
 "There are a few fixes for gfs2 but otherwise it's pretty quiet so far.

   - Only mark inode dirty at the end of writing to a file (instead of
     once for every page written).

   - Fix for an accounting error in the page_done callback"

* tag 'iomap-5.3-merge-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: fix page_done callback for short writes
  fs: fold __generic_write_end back into generic_write_end
  iomap: don't mark the inode dirty in iomap_write_end

Remove the unused flags argument of gfs2_iomap_alloc.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Rewrite gfs2_allocate_page_backing to call gfs2_iomap_get_alloc and operate on
struct iomap directly.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

No need to indirect through get_blocks and buffer_heads when we can just use
the iomap version.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>