Pull dlm updates from David Teigland:

 - Fix mistaken variable assignment that caused a refcounting problem

 - Revert a recent change that began using atomic counters where they
   were not needed (for lkb wait_count)

 - Add comments around forced state reset for waiting lock operations
   during recovery

* tag 'dlm-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  dlm: add comments about forced waiters reset
  dlm: revert atomic_t lkb_wait_count
  dlm: fix user space lkb refcounting

When a lock is waiting for a reply for a remote operation, and recovery
interrupts this "waiters" state, the remote operation is voided by the
recovery, and no reply will be processed.  The lkb waiters state for the
remote operation is forcibly reset/cleared, so that the lock operation
can be restarted after recovery.  Improve the comments describing this.

Signed-off-by: David Teigland <teigland@redhat.com>

Revert "fs: dlm: handle lkb wait count as atomic_t"
This reverts commit 75a7d60134ce84209f2c61ec4619ee543aa8f466.

This counter does not need to be atomic.  As the comment in
the reverted commit mentions, the counter is protected by
the rsb lock.

Signed-off-by: David Teigland <teigland@redhat.com>

This patch fixes to check on the right return value if it was the last
callback. The rv variable got overwritten by the return of
copy_result_to_user(). Fixing it by introducing a second variable for
the return value and don't let rv being overwritten.

Cc: stable@vger.kernel.org
Fixes: 61bed0baa4db ("fs: dlm: use a non-static queue for callbacks")
Reported-by: Valentin Vidić <vvidic@valentin-vidic.from.hr>
Closes: https://lore.kernel.org/gfs2/Ze4qSvzGJDt5yxC3@valentin-vidic.from.hr
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

Most of the existing APIs have remained the same, but subsystems that
access file_lock fields directly need to reach into struct
file_lock_core now.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240131-flsplit-v3-37-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

In a future patch, we're going to split file leases into their own
structure. Since a lot of the underlying machinery uses the same fields
move those into a new file_lock_core, and embed that inside struct
file_lock.

For now, add some macros to ensure that we can continue to build while
the conversion is in progress.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240131-flsplit-v3-17-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Convert to using the new file locking helper functions. Also, in later
patches we're going to introduce some temporary macros with names that
clash with the variable name in dlm_posix_unlock. Rename it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20240131-flsplit-v3-8-c6129007ee8d@kernel.org
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Over the time the dlm debugfs format string has been changed but the
header wasn't updated. This patch changes the first line dump header and
their meaning to reflect the current formats.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

This patch fixes to set the type 4 format ops in case of table_open4().
It got accidentially changed by commit 541adb0d4d10 ("fs: dlm: debugfs
for queued callbacks") and since them toss debug dumps the same format
as format 5 that are the queued ast callbacks for lkbs.

Fixes: 541adb0d4d10 ("fs: dlm: debugfs for queued callbacks")
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>

This patch uses the FL_SLEEP flag in struct file_lock to determine if
the lock request is a blocking or non-blocking request. Before dlm was
using IS_SETLKW() was being used which is not usable for lock requests
coming from lockd when EXPORT_OP_SAFE_ASYNC_LOCK inside the export flags
is set.

Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>