autofs-5.0.1 - fix submount shutdown wait

From: Ian Kent <raven@themaw.net>

When expiring a mount that has submounts we determine if a submount is
still in use by its state being other than ST_SHUTDOWN. But a submount
that is in the process of exiting could also be in one of the states
ST_SHUTDOWN_PENDING or ST_SHUTDOWN_FORCE, in which case we should also
continue to wait for the submount entry to be removed from the list or
for it to reach another state.
---

 lib/master.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)


--- autofs-5.0.1.orig/lib/master.c
+++ autofs-5.0.1/lib/master.c
@@ -935,8 +935,9 @@ int master_notify_submount(struct autofs
 		st_wait_task(this, state, 0);
 
 		/*
-		 * If our submount gets to state ST_SHUTDOWN we need to
-		 * wait until it goes away or changes to ST_READY.
+		 * If our submount gets to state ST_SHUTDOWN, ST_SHUTDOWN_PENDING or
+		 * ST_SHUTDOWN_FORCE we need to wait until it goes away or changes
+		 * to ST_READY.
 		 */
 		mounts_mutex_lock(ap);
 		st_mutex_lock();
@@ -944,7 +945,9 @@ int master_notify_submount(struct autofs
 			struct timespec t = { 0, 300000000 };
 			struct timespec r;
 
-			if (this->state != ST_SHUTDOWN) {
+			if (this->state != ST_SHUTDOWN &&
+			    this->state != ST_SHUTDOWN_PENDING &&
+			    this->state != ST_SHUTDOWN_FORCE) {
 				ret = 0;
 				break;
 			}