From f11ed3a236abe9ee07151a89324bc2e344d38117 Mon Sep 17 00:00:00 2001
From: neel <neel@FreeBSD.org>
Date: Wed, 22 Sep 2010 02:26:07 +0000
Subject: [PATCH] Enforce that 'pmap_kenter()' is only used to establish
 cacheable mappings.

Mappings with other cacheability attributes can be established, if needed,
by using 'pmap_kenter_attr()'.

Suggested by:	jchandra, imp
---
 sys/mips/include/pmap.h    |  1 +
 sys/mips/mips/pmap.c       | 11 ++++-------
 sys/mips/sibyte/sb_zbpci.c |  2 +-
 3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/sys/mips/include/pmap.h b/sys/mips/include/pmap.h
index e6aada96705a..558a0182ce83 100644
--- a/sys/mips/include/pmap.h
+++ b/sys/mips/include/pmap.h
@@ -154,6 +154,7 @@ void pmap_unmapdev(vm_offset_t, vm_size_t);
 vm_offset_t pmap_steal_memory(vm_size_t size);
 int page_is_managed(vm_offset_t pa);
 void pmap_kenter(vm_offset_t va, vm_paddr_t pa);
+void pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int attr);
 void pmap_kremove(vm_offset_t va);
 void *pmap_kenter_temporary(vm_paddr_t pa, int i);
 void pmap_kenter_temporary_free(vm_paddr_t pa);
diff --git a/sys/mips/mips/pmap.c b/sys/mips/mips/pmap.c
index 6d212f7513de..c39554fd3b49 100644
--- a/sys/mips/mips/pmap.c
+++ b/sys/mips/mips/pmap.c
@@ -828,7 +828,7 @@ retry:
 /*
  * add a wired page to the kva
  */
-static void
+void
 pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int attr)
 {
 	pt_entry_t *pte;
@@ -849,14 +849,11 @@ pmap_kenter_attr(vm_offset_t va, vm_paddr_t pa, int attr)
 void
 pmap_kenter(vm_offset_t va, vm_paddr_t pa)
 {
-	int attr;
 
-	if (is_cacheable_mem(pa))
-		attr = PTE_C_CACHE;
-	else
-		attr = PTE_C_UNCACHED;
+	KASSERT(is_cacheable_mem(pa),
+		("pmap_kenter: memory at 0x%lx is not cacheable", (u_long)pa));
 
-	pmap_kenter_attr(va, pa, attr);
+	pmap_kenter_attr(va, pa, PTE_C_CACHE);
 }
 
 /*
diff --git a/sys/mips/sibyte/sb_zbpci.c b/sys/mips/sibyte/sb_zbpci.c
index 9a096451f0a4..243ed08e7d7b 100644
--- a/sys/mips/sibyte/sb_zbpci.c
+++ b/sys/mips/sibyte/sb_zbpci.c
@@ -349,7 +349,7 @@ zbpci_config_space_va(int bus, int slot, int func, int reg, int bytes)
 		pa_page = pa & ~(PAGE_SIZE - 1);
 		if (zbpci_config_space[cpu].paddr != pa_page) {
 			pmap_kremove(va_page);
-			pmap_kenter(va_page, pa_page);
+			pmap_kenter_attr(va_page, pa_page, PTE_C_UNCACHED);
 			zbpci_config_space[cpu].paddr = pa_page;
 		}
 		return (va_page + (pa - pa_page));