ocfs2: clean up mount option about atime in ocfs2.txt

As ocfs2 supports relatime and strictatime, we need update the
relative document. Atime_quantum need work with strictatime, so only
show it in procfs when mount with strictatime.
Signed-off-by: NTiger Yang <tiger.yang@oracle.com>
Signed-off-by: NJoel Becker <jlbec@evilplan.org>

Documentation/filesystems/ocfs2.txt

@@ -46,9 +46,15 @@ errors=panic		Panic and halt the machine if an error occurs.
 intr		(*)	Allow signals to interrupt cluster operations.
 nointr			Do not allow signals to interrupt cluster
 			operations.
+noatime			Do not update access time.
+relatime(*)		Update atime if the previous atime is older than
+			mtime or ctime
+strictatime		Always update atime, but the minimum update interval
+			is specified by atime_quantum.
 atime_quantum=60(*)	OCFS2 will not update atime unless this number
 			of seconds has passed since the last update.
-			Set to zero to always update atime.
+			Set to zero to always update atime. This option need
+			work with strictatime.
 data=ordered	(*)	All data are forced directly out to the main file
 			system prior to its metadata being committed to the
 			journal.

fs/ocfs2/super.c

@@ -1566,7 +1566,7 @@ static int ocfs2_show_options(struct seq_file *s, struct vfsmount *mnt)
 	if (osb->preferred_slot != OCFS2_INVALID_SLOT)
 		seq_printf(s, ",preferred_slot=%d", osb->preferred_slot);
 
-	if (osb->s_atime_quantum != OCFS2_DEFAULT_ATIME_QUANTUM)
+	if (!(mnt->mnt_flags & MNT_NOATIME) && !(mnt->mnt_flags & MNT_RELATIME))
 		seq_printf(s, ",atime_quantum=%u", osb->s_atime_quantum);
 
 	if (osb->osb_commit_interval)