new locking scheme

[unix-history] / usr / src / sys / miscfs / union / union.h

diff --git a/usr/src/sys/miscfs/union/union.h b/usr/src/sys/miscfs/union/union.h
index 9657ba9..8041fb7 100644 (file)
--- a/usr/src/sys/miscfs/union/union.h
+++ b/usr/src/sys/miscfs/union/union.h
@@ -8,7 +8,7 @@
  *
  * %sccs.include.redist.c%
  *
  *
  * %sccs.include.redist.c%
  *

- *     @(#)union.h     1.9 (Berkeley) %G%
+ *     @(#)union.h     2.1 (Berkeley) %G%

  */
 
 struct union_args {
  */
 
 struct union_args {


@@ -56,8 +56,17 @@ struct union_node {
 #endif
 };
 
 #endif
 };
 

-#define UN_WANT 0x01
-#define UN_LOCKED 0x02
+#define UN_WANT                0x01
+#define UN_LOCKED      0x02
+#define UN_ULOCK       0x04            /* Upper node is locked */
+#define UN_KLOCK       0x08            /* Keep upper node locked on vput */
+
+#define LOCKUVP(un) \
+               (((un)->un_flags & UN_ULOCK) ? \
+                 (0) : \
+                 (((un)->un_flags |= UN_ULOCK), VOP_LOCK((un)->un_uppervp)))
+#define UNLOCKUVP(un) \
+               ((un)->un_flags &= ~UN_ULOCK)

 
 extern int union_allocvp __P((struct vnode **, struct mount *,
                                struct vnode *, struct vnode *,
 
 extern int union_allocvp __P((struct vnode **, struct mount *,
                                struct vnode *, struct vnode *,