Pull gfs2 fix from Andreas Gruenbacher:
 "Fix a memory leak on filesystem withdraw.

  We didn't detect this bug because we have slab merging on by default
  (CONFIG_SLAB_MERGE_DEFAULT). Adding 'slub_nomerge' to the kernel
  command line exposed the problem"

* tag 'gfs2-v5.9-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: add some much needed cleanup for log flushes that fail

When a log flush fails due to io errors, it signals the failure but does
not clean up after itself very well. This is because buffers are added to
the transaction tr_buf and tr_databuf queue, but the io error causes
gfs2_log_flush to bypass the "after_commit" functions responsible for
dequeueing the bd elements. If the bd elements are added to the ail list
before the error, function ail_drain takes care of dequeueing them.
But if they haven't gotten that far, the elements are forgotten and
make the transactions unable to be freed.

This patch introduces new function trans_drain which drains the bd
elements from the transaction so they can be freed properly.

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

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Pull gfs2 updates from Andreas Gruenbacher:

 - Make sure transactions won't be started recursively in
   gfs2_block_zero_range (bug introduced in 5.4 when switching to
   iomap_zero_range)

 - Fix a glock holder refcount leak introduced in the iopen glock
   locking scheme rework merged in 5.8.

 - A few other small improvements (debugging, stack usage, comment
   fixes).

* tag 'gfs2-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: When gfs2_dirty_inode gets a glock error, dump the glock
  gfs2: Never call gfs2_block_zero_range with an open transaction
  gfs2: print details on transactions that aren't properly ended
  gfs2: Fix inaccurate comment
  fs: Fix typo in comment
  gfs2: Fix refcount leak in gfs2_glock_poke
  gfs2: Pass glock holder to gfs2_file_direct_{read,write}
  gfs2: Add some flags missing from glock output

Before this patch, if function gfs2_dirty_inode got an error when
trying to lock the inode glock, it complained, but it didn't say
what glock or inode had the problem.

In this case, it almost always means that dinode_in found an error
with the dinode in the file system. So it makes sense to dump the
glock, which tells us the location of the dinode in the file system.
That will allow us to analyze the corruption from the metadata.

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

Before this patch, some functions started transactions then they called
gfs2_block_zero_range. However, gfs2_block_zero_range, like writes, can
start transactions, which results in a recursive transaction error.
For example:

do_shrink
   trunc_start
      gfs2_trans_begin <------------------------------------------------
         gfs2_block_zero_range
            iomap_zero_range(inode, from, length, NULL, &gfs2_iomap_ops);
               iomap_apply ... iomap_zero_range_actor
                  iomap_begin
                     gfs2_iomap_begin
                        gfs2_iomap_begin_write
                  actor (iomap_zero_range_actor)
		     iomap_zero
			iomap_write_begin
			   gfs2_iomap_page_prepare
			      gfs2_trans_begin <------------------------

This patch reorders the callers of gfs2_block_zero_range so that they
only start their transactions after the call. It also adds a BUG_ON to
ensure this doesn't happen again.

Fixes: 2257e468a63b ("gfs2: implement gfs2_block_zero_range using iomap_zero_range")
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

If function gfs2_trans_begin is called with another transaction active
it BUGs out, but it doesn't give any details about the duplicate.
This patch moves function gfs2_print_trans and calls it when this
situation arises for better debugging.

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

The comment regarding journal flush thresholds is wrong. This patch fixes it.

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

Pull iomap updates from Darrick Wong:
 "The most notable changes are:

   - iomap no longer invalidates the page cache when performing a direct
     read, since doing so is unnecessary and the old directio code
     doesn't do that either.

   - iomap embraced the use of returning ENOTBLK from a direct write to
     trigger falling back to a buffered write since ext4 already did
     this and btrfs wants it for their port.

   - iomap falls back to buffered writes if we're doing a direct write
     and the page cache invalidation after the flush fails; this was
     necessary to handle a corner case in the btrfs port.

   - Remove email virus scanner detritus that was accidentally included
     in yesterday's pull request. Clearly I need(ed) to update my git
     branch checker scripts. :("

* tag 'iomap-5.9-merge-5' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  iomap: fall back to buffered writes for invalidation failures
  xfs: use ENOTBLK for direct I/O to buffered I/O fallback
  iomap: Only invalidate page cache pages on direct IO writes
  iomap: Make sure iomap_end is called after iomap_begin

Failing to invalid the page cache means data in incoherent, which is
a very bad state for the system.  Always fall back to buffered I/O
through the page cache if we can't invalidate mappings.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Acked-by: Bob Peterson <rpeterso@redhat.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Theodore Ts'o <tytso@mit.edu> # for ext4
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com> # for gfs2
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>