uvm constraints. Add two mandatory MD symbols, uvm_md_constraints

which contains the constraints for DMA/memory allocation for each
architecture, and dma_constraints which contains the range of addresses
that are dma accessable by the system.

This is based on ariane@'s physcontig diff, with lots of bugfixes and
additions the following additions by my self:

Introduce a new function pool_set_constraints() which sets the address
range for which we allocate pages for the pool from, this is now used
for the mbuf/mbuf cluster pools to keep them dma accessible.

The !direct archs no longer stuff pages into the kernel object in
uvm_km_getpage_pla but rather do a pmap_extract() in uvm_km_putpages.

Tested heavily by my self on i386, amd64 and sparc64. Some tests on
alpha and SGI.

"commit it" beck, art, oga, deraadt
"i like the diff" deraadt

1 files changed, 9 insertions, 1 deletions

diff --git a/sys/arch/i386/i386/machdep.c b/sys/arch/i386/i386/machdep.c
index 2bf83682dc7..aa57e7c8821 100644
--- a/sys/arch/i386/i386/machdep.c
+++ b/sys/arch/i386/i386/machdep.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: machdep.c,v 1.473 2010/06/10 17:54:13 deraadt Exp $	*/
+/*	$OpenBSD: machdep.c,v 1.474 2010/06/27 03:03:48 thib Exp $	*/
 /*	$NetBSD: machdep.c,v 1.214 1996/11/10 03:16:17 thorpej Exp $	*/
 
 /*-
@@ -195,6 +195,14 @@ int	bufpages = 0;
 #endif
 int	bufcachepercent = BUFCACHEPERCENT;
 
+struct uvm_constraint_range  isa_constraint = { 0x0, 0x00ffffffUL };
+struct uvm_constraint_range  dma_constraint = { 0x0, 0xffffffffUL };
+struct uvm_constraint_range *uvm_md_constraints[] = {
+	&isa_constraint,
+	&dma_constraint,
+	NULL
+};
+
 extern int	boothowto;
 int	physmem;