svn commit: r250028 - head/sys/vm

[Konstantin Belousov]

Author: kib
Date: Sun Apr 28 19:19:26 2013
New Revision: 250028
URL: http://svnweb.freebsd.org/changeset/base/250028

Log:
  Assert that the object type for the vnode' non-NULL v_object, passed
  to vnode_pager_setsize(), is either OBJT_VNODE, or, if vnode was
  already reclaimed, OBJT_DEAD.  Note that the later is only possible
  due to some filesystems, in particular, nfsiods from nfs clients, call
  vnode_pager_setsize() with unlocked vnode.
  
  More, if the object is terminated, do not perform the resizing
  operation.
  
  Reviewed by:	alc
  Tested by:	pho, bf
  MFC after:	1 week

Modified:
  head/sys/vm/vnode_pager.c

Modified: head/sys/vm/vnode_pager.c
==============================================================================
--- head/sys/vm/vnode_pager.c	Sun Apr 28 19:12:09 2013	(r250027)
+++ head/sys/vm/vnode_pager.c	Sun Apr 28 19:19:26 2013	(r250028)
@@ -380,6 +380,12 @@ vnode_pager_setsize(vp, nsize)
 		return;
 /* 	ASSERT_VOP_ELOCKED(vp, "vnode_pager_setsize and not locked vnode"); */
 	VM_OBJECT_WLOCK(object);
+	if (object->type == OBJT_DEAD) {
+		VM_OBJECT_WUNLOCK(object);
+		return;
+	}
+	KASSERT(object->type == OBJT_VNODE,
+	    ("not vnode-backed object %p", object));
 	if (nsize == object->un_pager.vnp.vnp_size) {
 		/*
 		 * Hasn't changed size