diff --git a/fs/locks.c b/fs/locks.c
index 43dbc7f..9a3fe0d 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -1119,7 +1119,7 @@
 			 * If we've been sleeping someone might have
 			 * changed the permissions behind our back.
 			 */
-			if ((inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID)
+			if (__mandatory_lock(inode))
 				continue;
 		}
 
@@ -1761,9 +1761,7 @@
 	/* Don't allow mandatory locks on files that may be memory mapped
 	 * and shared.
 	 */
-	if (IS_MANDLOCK(inode) &&
-	    (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
-	    mapping_writably_mapped(filp->f_mapping)) {
+	if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) {
 		error = -EAGAIN;
 		goto out;
 	}
@@ -1887,9 +1885,7 @@
 	/* Don't allow mandatory locks on files that may be memory mapped
 	 * and shared.
 	 */
-	if (IS_MANDLOCK(inode) &&
-	    (inode->i_mode & (S_ISGID | S_IXGRP)) == S_ISGID &&
-	    mapping_writably_mapped(filp->f_mapping)) {
+	if (mandatory_lock(inode) && mapping_writably_mapped(filp->f_mapping)) {
 		error = -EAGAIN;
 		goto out;
 	}
@@ -2083,9 +2079,7 @@
 		out += sprintf(out, "%6s %s ",
 			     (fl->fl_flags & FL_ACCESS) ? "ACCESS" : "POSIX ",
 			     (inode == NULL) ? "*NOINODE*" :
-			     (IS_MANDLOCK(inode) &&
-			      (inode->i_mode & (S_IXGRP | S_ISGID)) == S_ISGID) ?
-			     "MANDATORY" : "ADVISORY ");
+			     mandatory_lock(inode) ? "MANDATORY" : "ADVISORY ");
 	} else if (IS_FLOCK(fl)) {
 		if (fl->fl_type & LOCK_MAND) {
 			out += sprintf(out, "FLOCK  MSNFS     ");