svn commit: r232645 - stable/9/sys/fs/nullfs

[Konstantin Belousov]

Author: kib
Date: Wed Mar  7 08:05:12 2012
New Revision: 232645
URL: http://svn.freebsd.org/changeset/base/232645

Log:
  MFC r232303:
  In null_reclaim(), assert that reclaimed vnode is fully constructed,
  instead of accepting half-constructed vnode. Previous code cannot decide
  what to do with such vnode anyway, and although processing it for hash
  removal, paniced later when getting rid of nullfs reference on lowervp.
  
  While there, remove initializations from the declaration block.

Modified:
  stable/9/sys/fs/nullfs/null_vnops.c
Directory Properties:
  stable/9/sys/   (props changed)

Modified: stable/9/sys/fs/nullfs/null_vnops.c
==============================================================================
--- stable/9/sys/fs/nullfs/null_vnops.c	Wed Mar  7 08:02:43 2012	(r232644)
+++ stable/9/sys/fs/nullfs/null_vnops.c	Wed Mar  7 08:05:12 2012	(r232645)
@@ -697,12 +697,18 @@ null_inactive(struct vop_inactive_args *
 static int
 null_reclaim(struct vop_reclaim_args *ap)
 {
-	struct vnode *vp = ap->a_vp;
-	struct null_node *xp = VTONULL(vp);
-	struct vnode *lowervp = xp->null_lowervp;
+	struct vnode *vp;
+	struct null_node *xp;
+	struct vnode *lowervp;
+
+	vp = ap->a_vp;
+	xp = VTONULL(vp);
+	lowervp = xp->null_lowervp;
+
+	KASSERT(lowervp != NULL && vp->v_vnlock != &vp->v_lock,
+	    ("Reclaiming inclomplete null vnode %p", vp));
 
-	if (lowervp)
-		null_hashrem(xp);
+	null_hashrem(xp);
 	/*
 	 * Use the interlock to protect the clearing of v_data to
 	 * prevent faults in null_lock().
@@ -713,10 +719,7 @@ null_reclaim(struct vop_reclaim_args *ap
 	vp->v_object = NULL;
 	vp->v_vnlock = &vp->v_lock;
 	VI_UNLOCK(vp);
-	if (lowervp)
-		vput(lowervp);
-	else
-		panic("null_reclaim: reclaiming a node with no lowervp");
+	vput(lowervp);
 	free(xp, M_NULLFSNODE);
 
 	return (0);