dm integrity: change 'suspending' variable from bool to int

Early alpha processors can't write a byte or short atomically - they
read 8 bytes, modify the byte or two bytes in registers and write back
8 bytes.

The modification of the variable "suspending" may race with
modification of the variable "failed".  Fix this by changing
"suspending" to an int.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

drivers/md/dm-integrity.c

@@ -178,7 +178,7 @@ struct dm_integrity_c {
 	__u8 sectors_per_block;
 
 	unsigned char mode;
-	bool suspending;
+	int suspending;
 
 	int failed;
 
@@ -2210,7 +2210,7 @@ static void dm_integrity_postsuspend(struct dm_target *ti)
 
 	del_timer_sync(&ic->autocommit_timer);
 
-	ic->suspending = true;
+	WRITE_ONCE(ic->suspending, 1);
 
 	queue_work(ic->commit_wq, &ic->commit_work);
 	drain_workqueue(ic->commit_wq);
@@ -2220,7 +2220,7 @@ static void dm_integrity_postsuspend(struct dm_target *ti)
 		dm_integrity_flush_buffers(ic);
 	}
 
-	ic->suspending = false;
+	WRITE_ONCE(ic->suspending, 0);
 
 	BUG_ON(!RB_EMPTY_ROOT(&ic->in_progress));