svn commit: r193124 - head/sys/vm

[Alan Cox]

Author: alc
Date: Sat May 30 22:06:58 2009
New Revision: 193124
URL: http://svn.freebsd.org/changeset/base/193124

Log:
  Add assertions in two places where a page's valid or dirty bits are changed.

Modified:
  head/sys/vm/vm_page.c

Modified: head/sys/vm/vm_page.c
==============================================================================
--- head/sys/vm/vm_page.c	Sat May 30 22:04:18 2009	(r193123)
+++ head/sys/vm/vm_page.c	Sat May 30 22:06:58 2009	(r193124)
@@ -566,10 +566,13 @@ vm_page_sleep(vm_page_t m, const char *m
 void
 vm_page_dirty(vm_page_t m)
 {
+
 	KASSERT((m->flags & PG_CACHED) == 0,
 	    ("vm_page_dirty: page in cache!"));
 	KASSERT(!VM_PAGE_IS_FREE(m),
 	    ("vm_page_dirty: page is free!"));
+	KASSERT(m->valid == VM_PAGE_BITS_ALL,
+	    ("vm_page_dirty: page is invalid!"));
 	m->dirty = VM_PAGE_BITS_ALL;
 }
 
@@ -1891,6 +1894,13 @@ vm_page_set_valid(vm_page_t m, int base,
 		    DEV_BSIZE - (endoff & (DEV_BSIZE - 1)));
 
 	/*
+	 * Assert that no previously invalid block that is now being validated
+	 * is already dirty. 
+	 */
+	KASSERT((~m->valid & vm_page_bits(base, size) & m->dirty) == 0,
+	    ("vm_page_set_valid: page %p is dirty", m)); 
+
+	/*
 	 * Set valid bits inclusive of any overlap.
 	 */
 	m->valid |= vm_page_bits(base, size);