locks: make /proc/locks show IS_FILE_PVT locks as type "FLPVT"

In a later patch, we'll be adding a new type of lock that's owned by
the struct file instead of the files_struct. Those sorts of locks
will be flagged with a new FL_FILE_PVT flag.

Report these types of locks as "FLPVT" in /proc/locks to distinguish
them from "classic" POSIX locks.

Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
diff --git a/fs/locks.c b/fs/locks.c
index 4d4e790..0e1f0df 100644
--- a/fs/locks.c
+++ b/fs/locks.c
@@ -135,6 +135,7 @@
 #define IS_POSIX(fl)	(fl->fl_flags & FL_POSIX)
 #define IS_FLOCK(fl)	(fl->fl_flags & FL_FLOCK)
 #define IS_LEASE(fl)	(fl->fl_flags & (FL_LEASE|FL_DELEG))
+#define IS_FILE_PVT(fl)	(fl->fl_flags & FL_FILE_PVT)
 
 static bool lease_breaking(struct file_lock *fl)
 {
@@ -2313,8 +2314,14 @@
 
 	seq_printf(f, "%lld:%s ", id, pfx);
 	if (IS_POSIX(fl)) {
-		seq_printf(f, "%6s %s ",
-			     (fl->fl_flags & FL_ACCESS) ? "ACCESS" : "POSIX ",
+		if (fl->fl_flags & FL_ACCESS)
+			seq_printf(f, "ACCESS");
+		else if (IS_FILE_PVT(fl))
+			seq_printf(f, "FLPVT ");
+		else
+			seq_printf(f, "POSIX ");
+
+		seq_printf(f, " %s ",
 			     (inode == NULL) ? "*NOINODE*" :
 			     mandatory_lock(inode) ? "MANDATORY" : "ADVISORY ");
 	} else if (IS_FLOCK(fl)) {