High memory page flipping for the buffer cache.

This change splits the buffer cache free lists into lists of dma reachable
buffers and high memory buffers based on the ranges returned by pmemrange.
Buffers move from dma to high memory as they age, but are flipped to dma
reachable memory if IO is needed to/from and high mem buffer. The total
amount of buffers  allocated is now bufcachepercent of both the dma and
the high memory region.

This change allows the use of large buffer caches on amd64 using more than
4 GB of memory

ok tedu@ krw@ - testing by many.

1 files changed, 4 insertions, 2 deletions

diff --git a/sys/kern/spec_vnops.c b/sys/kern/spec_vnops.c
index 2bc2e43711b..d2bc271cfb0 100644
--- a/sys/kern/spec_vnops.c
+++ b/sys/kern/spec_vnops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: spec_vnops.c,v 1.72 2013/06/11 16:42:16 deraadt Exp $	*/
+/*	$OpenBSD: spec_vnops.c,v 1.73 2013/06/11 19:01:20 beck Exp $	*/
 /*	$NetBSD: spec_vnops.c,v 1.29 1996/04/22 01:42:38 christos Exp $	*/
 
 /*
@@ -457,7 +457,9 @@ spec_strategy(void *v)
 	struct vop_strategy_args *ap = v;
 	struct buf *bp = ap->a_bp;
 	int maj = major(bp->b_dev);
-	
+
+	if (!ISSET(bp->b_flags, B_DMA) && ISSET(bp->b_flags, B_BC))
+		panic("bogus buf %p passed to spec_strategy", bp);
 	if (LIST_FIRST(&bp->b_dep) != NULL)
 		buf_start(bp);