dlm: add new flag DLM_RELEASE_RECOVER for dlm_lockspace_release

When dlm_lockspace_release() is passed DLM_RELEASE_RECOVER, it
tells the dlm to handle the release/leave as if the node had failed,
i.e. perform recovery steps for a failed node, like recover_slot().

When DLM_RELEASE_RECOVER is set:
- dlm_release_lockspace() includes RELEASE_RECOVER=1 in the OFFLINE
  uevent sent to userspace.
- userspace/dlm_controld sends a message to all lockspace members
  indicating that the subsequent node removal should be handled as
  if the node had failed.
- when dlm_controld on all nodes receives the new message, it sets
  the release_recover configfs entry to 1 for the node.
- when the dlm/kernel next performs recovery and removes the node,
  it will see that release_recover has been set, and will perform
  recovery steps for the node as if it had failed, e.g. the
  recover_slot() callback is called to notify the fs.

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

1 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/dlm.h b/include/linux/dlm.h
index cc7a36244893..108eb953eb18 100644
--- a/include/linux/dlm.h
+++ b/include/linux/dlm.h
@@ -103,11 +103,16 @@ int dlm_new_lockspace(const char *name, const char *cluster,
  *   a leave event to the cluster manager, so other nodes will
  *   not be notified that the node should be removed from the
  *   list of lockspace members.
+ *
+ * DLM_RELEASE_RECOVER like DLM_RELEASE_NORMAL, but the remaining
+ *   nodes will handle the removal of the node as if the node
+ *   had failed, e.g. the recover_slot() callback would be used.
  */
 #define DLM_RELEASE_NO_LOCKS		0
 #define DLM_RELEASE_UNUSED		1
 #define DLM_RELEASE_NORMAL		2
 #define DLM_RELEASE_NO_EVENT		3
+#define DLM_RELEASE_RECOVER		4
 
 /*
  * dlm_release_lockspace