The pgrot_<type>() interfaces only set the _PAGE_PCD and/or
_PAGE_PWT bits by assuming that a given pgprot_t value is always
set to the PA0 slot.
This patch changes the pgrot_<type>() interfaces to assure that
a requested memory type is set to the given pgprot_t regardless
of the original pgprot_t value.
Signed-off-by: Toshi Kani <toshi.k...@hp.com>
---
arch/x86/include/asm/pgtable.h | 2 +-
arch/x86/include/asm/pgtable_types.h | 4 ++++
arch/x86/mm/pat.c | 4 ++--
3 files changed, 7 insertions(+), 3 deletions(-)
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index 0ec0560..df18b14 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -11,7 +11,7 @@
*/
#define pgprot_noncached(prot) \
((boot_cpu_data.x86 > 3) \
- ? (__pgprot(pgprot_val(prot) | _PAGE_CACHE_UC_MINUS)) \
+ ? pgprot_set_cache(prot, _PAGE_CACHE_UC_MINUS) \
: (prot))
#ifndef __ASSEMBLY__
diff --git a/arch/x86/include/asm/pgtable_types.h
b/arch/x86/include/asm/pgtable_types.h
index 1fe8af7..81a3859 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -136,6 +136,10 @@
#define _PAGE_CACHE_UC_MINUS (_PAGE_PCD)
#define _PAGE_CACHE_UC (_PAGE_CACHE_UC_MINUS)
+/* Macro to set a page cache value */
+#define pgprot_set_cache(_prot, _type) \
+ __pgprot((pgprot_val(_prot) & ~_PAGE_CACHE_MASK) | (_type))
+
#define PAGE_NONE __pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \
_PAGE_ACCESSED | _PAGE_NX)
diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index a987071..0be7ebd 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -790,7 +790,7 @@ void untrack_pfn(struct vm_area_struct *vma, unsigned long
pfn,
pgprot_t pgprot_writecombine(pgprot_t prot)
{
if (pat_enabled)
- return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WC);
+ return pgprot_set_cache(prot, _PAGE_CACHE_WC);
else
return pgprot_noncached(prot);
}
@@ -799,7 +799,7 @@ EXPORT_SYMBOL_GPL(pgprot_writecombine);
pgprot_t pgprot_writethrough(pgprot_t prot)
{
if (pat_enabled)
- return __pgprot(pgprot_val(prot) | _PAGE_CACHE_WT);
+ return pgprot_set_cache(prot, _PAGE_CACHE_WT);
else
return pgprot_noncached(prot);
}
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
