--- Net2/vm/vm_page.c	2018/04/24 18:09:24	1.1.1.3
+++ Net2/vm/vm_page.c	2018/04/24 18:15:00	1.1.1.4
@@ -33,7 +33,8 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	@(#)vm_page.c	7.4 (Berkeley) 5/7/91
+ *	from: @(#)vm_page.c	7.4 (Berkeley) 5/7/91
+ *	vm_page.c,v 1.5 1993/06/30 03:48:25 andrew Exp
  *
  *
  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
@@ -60,14 +61,6 @@
  *
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
- *
- * PATCHES MAGIC                LEVEL   PATCH THAT GOT US HERE
- * --------------------         -----   ----------------------
- * CURRENT PATCH LEVEL:         1       00074
- * --------------------         -----   ----------------------
- *
- * 22 Jan 93	Paul Mackerras		Fixed bug where pages got lost
- *
  */
 
 /*
@@ -263,7 +256,7 @@ vm_offset_t vm_page_startup(start, end,
 	 */
 
 	vm_page_free_count = npages =
-		(end - start)/(PAGE_SIZE + sizeof(struct vm_page));
+		(end - start + sizeof(struct vm_page))/(PAGE_SIZE + sizeof(struct vm_page));
 
 	/*
 	 *	Initialize the mem entry structures now, and
@@ -555,6 +548,14 @@ vm_page_t vm_page_alloc(object, offset)
 
 	spl = splimp();				/* XXX */
 	simple_lock(&vm_page_queue_free_lock);
+	if (	object != kernel_object &&
+		object != kmem_object	&&
+		vm_page_free_count <= vm_page_free_reserved) {
+
+		simple_unlock(&vm_page_queue_free_lock);
+		splx(spl);
+		return(NULL);
+	}
 	if (queue_empty(&vm_page_queue_free)) {
 		simple_unlock(&vm_page_queue_free_lock);
 		splx(spl);