svn commit: r222991 - head/sys/vm

[Konstantin Belousov]

Author: kib
Date: Sat Jun 11 20:13:28 2011
New Revision: 222991
URL: http://svn.freebsd.org/changeset/base/222991

Log:
  Fix a bug in r222586. Lock the page owner object around the modification
  of the m->dirty.
  
  Reported and tested by:	nwhitehorn
  Reviewed by:	alc

Modified:
  head/sys/vm/vnode_pager.c

Modified: head/sys/vm/vnode_pager.c
==============================================================================
--- head/sys/vm/vnode_pager.c	Sat Jun 11 18:39:55 2011	(r222990)
+++ head/sys/vm/vnode_pager.c	Sat Jun 11 20:13:28 2011	(r222991)
@@ -1195,8 +1195,13 @@ vnode_pager_generic_putpages(struct vnod
 void
 vnode_pager_undirty_pages(vm_page_t *ma, int *rtvals, int written)
 {
+	vm_object_t obj;
 	int i, pos;
 
+	if (written == 0)
+		return;
+	obj = ma[0]->object;
+	VM_OBJECT_LOCK(obj);
 	for (i = 0, pos = 0; pos < written; i++, pos += PAGE_SIZE) {
 		if (pos < trunc_page(written)) {
 			rtvals[i] = VM_PAGER_OK;
@@ -1207,4 +1212,5 @@ vnode_pager_undirty_pages(vm_page_t *ma,
 			vm_page_clear_dirty(ma[i], 0, written & PAGE_MASK);
 		}
 	}
+	VM_OBJECT_UNLOCK(obj);
 }