These changes embody the support of the fully coherent merged VM buffer cache,

much higher filesystem I/O performance, and much better paging performance. It
represents the culmination of over 6 months of R&D.

The majority of the merged VM/cache work is by John Dyson.

The following highlights the most significant changes. Additionally, there are
(mostly minor) changes to the various filesystem modules (nfs, msdosfs, etc) to
support the new VM/buffer scheme.

vfs_bio.c:
Significant rewrite of most of vfs_bio to support the merged VM buffer cache
scheme.  The scheme is almost fully compatible with the old filesystem
interface.  Significant improvement in the number of opportunities for write
clustering.

vfs_cluster.c, vfs_subr.c
Upgrade and performance enhancements in vfs layer code to support merged
VM/buffer cache.  Fixup of vfs_cluster to eliminate the bogus pagemove stuff.

vm_object.c:
Yet more improvements in the collapse code.  Elimination of some windows that
can cause list corruption.

vm_pageout.c:
Fixed it, it really works better now.  Somehow in 2.0, some "enhancements"
broke the code.  This code has been reworked from the ground-up.

vm_fault.c, vm_page.c, pmap.c, vm_object.c
Support for small-block filesystems with merged VM/buffer cache scheme.

pmap.c vm_map.c
Dynamic kernel VM size, now we dont have to pre-allocate excessive numbers of
kernel PTs.

vm_glue.c
Much simpler and more effective swapping code.  No more gratuitous swapping.

proc.h
Fixed the problem that the p_lock flag was not being cleared on a fork.

swap_pager.c, vnode_pager.c
Removal of old vfs_bio cruft to support the past pseudo-coherency.  Now the
code doesn't need it anymore.

machdep.c
Changes to better support the parameter values for the merged VM/buffer cache
scheme.

machdep.c, kern_exec.c, vm_glue.c
Implemented a seperate submap for temporary exec string space and another one
to contain process upages. This eliminates all map fragmentation problems
that previously existed.

ffs_inode.c, ufs_inode.c, ufs_readwrite.c
Changes for merged VM/buffer cache.  Add "bypass" support for sneaking in on
busy buffers.

Submitted by:	John Dyson and David Greenman

1 files changed, 21 insertions, 17 deletions

diff --git a/sys/vm/vm_pageout.h b/sys/vm/vm_pageout.h
index 77c4373..562a2ac 100644
--- a/sys/vm/vm_pageout.h
+++ b/sys/vm/vm_pageout.h
@@ -1,4 +1,4 @@
-/* 
+/*
  * Copyright (c) 1991, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -40,17 +40,17 @@
  * All rights reserved.
  *
  * Author: Avadis Tevanian, Jr.
- * 
+ *
  * Permission to use, copy, modify and distribute this software and
  * its documentation is hereby granted, provided that both the copyright
  * notice and this permission notice appear in all copies of the
  * software, derivative works or modified versions, and any portions
  * thereof, and that both notices appear in supporting documentation.
- * 
- * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 
- * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 
+ *
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
- * 
+ *
  * Carnegie Mellon requests users of this software to return to
  *
  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
@@ -61,7 +61,7 @@
  * any improvements or extensions that they make and grant Carnegie the
  * rights to redistribute these changes.
  *
- * $Id: vm_pageout.h,v 1.5 1994/08/21 07:19:45 paul Exp $
+ * $Id: vm_pageout.h,v 1.6 1994/10/09 01:52:16 phk Exp $
  */
 
 #ifndef _VM_VM_PAGEOUT_H_
@@ -75,8 +75,8 @@
  *	Exported data structures.
  */
 
-extern int	vm_pages_needed;	/* should be some "event" structure */
-simple_lock_data_t	vm_pages_needed_lock;
+extern int vm_pages_needed;	/* should be some "event" structure */
+simple_lock_data_t vm_pages_needed_lock;
 extern int vm_pageout_pages_needed;
 
 #define VM_PAGEOUT_ASYNC 0
@@ -93,26 +93,30 @@ extern int vm_pageout_pages_needed;
 
 #define VM_WAIT vm_wait()
 
-inline static void vm_wait() {
+inline static void 
+vm_wait()
+{
 	int s;
+
 	s = splhigh();
 	if (curproc == pageproc) {
 		vm_pageout_pages_needed = 1;
-		tsleep((caddr_t) &vm_pageout_pages_needed, PSWP, "vmwait", 0);
+		tsleep((caddr_t) & vm_pageout_pages_needed, PSWP, "vmwait", 0);
 		vm_pageout_pages_needed = 0;
 	} else {
-		wakeup((caddr_t) &vm_pages_needed);
-		tsleep((caddr_t) &cnt.v_free_count, PVM, "vmwait", 0);
+		wakeup((caddr_t) & vm_pages_needed);
+		tsleep((caddr_t) & cnt.v_free_count, PVM, "vmwait", 0);
 	}
 	splx(s);
 }
 
 
 #ifdef KERNEL
-int		 vm_pageout_scan __P((void));
-void		 vm_pageout_page __P((vm_page_t, vm_object_t));
-void		 vm_pageout_cluster __P((vm_page_t, vm_object_t));
-int		vm_pageout_clean __P((vm_page_t, int));
+int vm_pageout_scan __P((void));
+void vm_pageout_page __P((vm_page_t, vm_object_t));
+void vm_pageout_cluster __P((vm_page_t, vm_object_t));
+int vm_pageout_clean __P((vm_page_t, int));
+
 #endif
 
 #endif