summaryrefslogtreecommitdiff
path: root/sys/vm/vm_page.h
diff options
context:
space:
mode:
Diffstat (limited to 'sys/vm/vm_page.h')
-rw-r--r--sys/vm/vm_page.h15
1 files changed, 12 insertions, 3 deletions
diff --git a/sys/vm/vm_page.h b/sys/vm/vm_page.h
index 584d7365f58..14a529cf9fe 100644
--- a/sys/vm/vm_page.h
+++ b/sys/vm/vm_page.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: vm_page.h,v 1.2 1996/08/02 00:06:03 niklas Exp $ */
+/* $OpenBSD: vm_page.h,v 1.3 1996/08/13 22:22:17 niklas Exp $ */
/* $NetBSD: vm_page.h,v 1.18 1995/03/26 20:39:13 jtc Exp $ */
/*
@@ -121,8 +121,17 @@ struct vm_page {
*/
#define PG_INACTIVE 0x0001 /* page is in inactive list (P) */
#define PG_ACTIVE 0x0002 /* page is in active list (P) */
-#define PG_LAUNDRY 0x0004 /* page is being cleaned now (P)*/
-#define PG_CLEAN 0x0008 /* page has not been modified */
+#define PG_LAUNDRY 0x0004 /* page is being cleaned now (P) */
+#define PG_CLEAN 0x0008 /* page has not been modified
+ There exists a case where this bit
+ will be cleared, although the page
+ is not physically dirty, which is
+ when a collapse operation moves
+ pages between two different pagers.
+ The bit is then used as a marker
+ for the pageout daemon to know it
+ should be paged out into the target
+ pager. */
#define PG_BUSY 0x0010 /* page is in transit (O) */
#define PG_WANTED 0x0020 /* someone is waiting for page (O) */
#define PG_TABLED 0x0040 /* page is in VP table (O) */