ocfs2: switch osb->disable_recovery to enum

Patch series "ocfs2: Fix deadlocks in quota recovery", v3.

This implements another approach to fixing quota recovery deadlocks.  We
avoid grabbing sb->s_umount semaphore from ocfs2_finish_quota_recovery()
and instead stop quota recovery early in ocfs2_dismount_volume().


This patch (of 3):

We will need more recovery states than just pure enable / disable to fix
deadlocks with quota recovery.  Switch osb->disable_recovery to enum.

Link: https://lkml.kernel.org/r/[email protected]
Link: https://lkml.kernel.org/r/[email protected]
Fixes: 5f530de ("ocfs2: Use s_umount for quota recovery protection")
Signed-off-by: Jan Kara <[email protected]>
Reviewed-by: Heming Zhao <[email protected]>
Tested-by: Heming Zhao <[email protected]>
Acked-by: Joseph Qi <[email protected]>
Cc: Mark Fasheh <[email protected]>
Cc: Joel Becker <[email protected]>
Cc: Junxiao Bi <[email protected]>
Cc: Changwei Ge <[email protected]>
Cc: Jun Piao <[email protected]>
Cc: Murad Masimov <[email protected]>
Cc: Shichangkuo <[email protected]>
Cc: <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

Author: jankara

fs/ocfs2/journal.c

@@ -174,7 +174,7 @@ int ocfs2_recovery_init(struct ocfs2_super *osb)
 	struct ocfs2_recovery_map *rm;
 
 	mutex_init(&osb->recovery_lock);
-	osb->disable_recovery = 0;
+	osb->recovery_state = OCFS2_REC_ENABLED;
 	osb->recovery_thread_task = NULL;
 	init_waitqueue_head(&osb->recovery_event);
 
@@ -206,7 +206,7 @@ void ocfs2_recovery_exit(struct ocfs2_super *osb)
 	/* disable any new recovery threads and wait for any currently
 	 * running ones to exit. Do this before setting the vol_state. */
 	mutex_lock(&osb->recovery_lock);
-	osb->disable_recovery = 1;
+	osb->recovery_state = OCFS2_REC_DISABLED;
 	mutex_unlock(&osb->recovery_lock);
 	wait_event(osb->recovery_event, !ocfs2_recovery_thread_running(osb));
 
@@ -1582,14 +1582,16 @@ static int __ocfs2_recovery_thread(void *arg)
 
 void ocfs2_recovery_thread(struct ocfs2_super *osb, int node_num)
 {
+	int was_set = -1;
+
 	mutex_lock(&osb->recovery_lock);
+	if (osb->recovery_state < OCFS2_REC_DISABLED)
+		was_set = ocfs2_recovery_map_set(osb, node_num);
 
 	trace_ocfs2_recovery_thread(node_num, osb->node_num,
-		osb->disable_recovery, osb->recovery_thread_task,
-		osb->disable_recovery ?
-		-1 : ocfs2_recovery_map_set(osb, node_num));
+		osb->recovery_state, osb->recovery_thread_task, was_set);
 
-	if (osb->disable_recovery)
+	if (osb->recovery_state == OCFS2_REC_DISABLED)
 		goto out;
 
 	if (osb->recovery_thread_task)

fs/ocfs2/ocfs2.h

@@ -308,6 +308,11 @@ enum ocfs2_journal_trigger_type {
 void ocfs2_initialize_journal_triggers(struct super_block *sb,
 				       struct ocfs2_triggers triggers[]);
 
+enum ocfs2_recovery_state {
+	OCFS2_REC_ENABLED = 0,
+	OCFS2_REC_DISABLED,
+};
+
 struct ocfs2_journal;
 struct ocfs2_slot_info;
 struct ocfs2_recovery_map;
@@ -370,7 +375,7 @@ struct ocfs2_super
 	struct ocfs2_recovery_map *recovery_map;
 	struct ocfs2_replay_map *replay_map;
 	struct task_struct *recovery_thread_task;
-	int disable_recovery;
+	enum ocfs2_recovery_state recovery_state;
 	wait_queue_head_t checkpoint_event;
 	struct ocfs2_journal *journal;
 	unsigned long osb_commit_interval;