ceph: add acl, noacl options for cephfs mount

Make the 'acl' option dependent on having ACL support compiled in.  Make
the 'noacl' option work even without it so that one can always ask it to
be off and not error out on mount when it is not supported.

Signed-off-by: Guangliang Zhao <lucienchao@gmail.com>
Signed-off-by: Sage Weil <sage@inktank.com>
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 2df963f..10a4ccb 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -144,7 +144,11 @@
 	Opt_ino32,
 	Opt_noino32,
 	Opt_fscache,
-	Opt_nofscache
+	Opt_nofscache,
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	Opt_acl,
+#endif
+	Opt_noacl
 };
 
 static match_table_t fsopt_tokens = {
@@ -172,6 +176,10 @@
 	{Opt_noino32, "noino32"},
 	{Opt_fscache, "fsc"},
 	{Opt_nofscache, "nofsc"},
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	{Opt_acl, "acl"},
+#endif
+	{Opt_noacl, "noacl"},
 	{-1, NULL}
 };
 
@@ -271,6 +279,14 @@
 	case Opt_nofscache:
 		fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
 		break;
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	case Opt_acl:
+		fsopt->sb_flags |= MS_POSIXACL;
+		break;
+#endif
+	case Opt_noacl:
+		fsopt->sb_flags &= ~MS_POSIXACL;
+		break;
 	default:
 		BUG_ON(token);
 	}
@@ -438,6 +454,13 @@
 	else
 		seq_puts(m, ",nofsc");
 
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	if (fsopt->sb_flags & MS_POSIXACL)
+		seq_puts(m, ",acl");
+	else
+		seq_puts(m, ",noacl");
+#endif
+
 	if (fsopt->wsize)
 		seq_printf(m, ",wsize=%d", fsopt->wsize);
 	if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
@@ -819,9 +842,6 @@
 
 	s->s_flags = fsc->mount_options->sb_flags;
 	s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
-#ifdef CONFIG_CEPH_FS_POSIX_ACL
-	s->s_flags |= MS_POSIXACL;
-#endif
 
 	s->s_xattr = ceph_xattr_handlers;
 	s->s_fs_info = fsc;
@@ -911,6 +931,10 @@
 	struct ceph_options *opt = NULL;
 
 	dout("ceph_mount\n");
+
+#ifdef CONFIG_CEPH_FS_POSIX_ACL
+	flags |= MS_POSIXACL;
+#endif
 	err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
 	if (err < 0) {
 		res = ERR_PTR(err);