dlm: fixes for nodir mode

The "nodir" mode (statically assign master nodes instead
of using the resource directory) has always been highly
experimental, and never seriously used.  This commit
fixes a number of problems, making nodir much more usable.

- Major change to recovery: recover all locks and restart
  all in-progress operations after recovery.  In some
  cases it's not possible to know which in-progess locks
  to recover, so recover all.  (Most require recovery
  in nodir mode anyway since rehashing changes most
  master nodes.)

- Change the way nodir mode is enabled, from a command
  line mount arg passed through gfs2, into a sysfs
  file managed by dlm_controld, consistent with the
  other config settings.

- Allow recovering MSTCPY locks on an rsb that has not
  yet been turned into a master copy.

- Ignore RCOM_LOCK and RCOM_LOCK_REPLY recovery messages
  from a previous, aborted recovery cycle.  Base this
  on the local recovery status not being in the state
  where any nodes should be sending LOCK messages for the
  current recovery cycle.

- Hold rsb lock around dlm_purge_mstcpy_locks() because it
  may run concurrently with dlm_recover_master_copy().

- Maintain highbast on process-copy lkb's (in addition to
  the master as is usual), because the lkb can switch
  back and forth between being a master and being a
  process copy as the master node changes in recovery.

- When recovering MSTCPY locks, flag rsb's that have
  non-empty convert or waiting queues for granting
  at the end of recovery.  (Rename flag from LOCKS_PURGED
  to RECOVER_GRANT and similar for the recovery function,
  because it's not only resources with purged locks
  that need grant a grant attempt.)

- Replace a couple of unnecessary assertion panics with
  error messages.

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

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/dlm/lock.h b/fs/dlm/lock.h
index 56e2bc646565..c8b226c62807 100644
--- a/fs/dlm/lock.h
+++ b/fs/dlm/lock.h
@@ -32,9 +32,9 @@ void dlm_adjust_timeouts(struct dlm_ls *ls);
 int dlm_search_rsb_tree(struct rb_root *tree, char *name, int len,
 			unsigned int flags, struct dlm_rsb **r_ret);
 
-int dlm_purge_locks(struct dlm_ls *ls);
+void dlm_recover_purge(struct dlm_ls *ls);
 void dlm_purge_mstcpy_locks(struct dlm_rsb *r);
-void dlm_grant_after_purge(struct dlm_ls *ls);
+void dlm_recover_grant(struct dlm_ls *ls);
 int dlm_recover_waiters_post(struct dlm_ls *ls);
 void dlm_recover_waiters_pre(struct dlm_ls *ls);
 int dlm_recover_master_copy(struct dlm_ls *ls, struct dlm_rcom *rc);