powerpc/mm: Define flags for Strong Access Ordering
This patch defines:
- PROT_SAO, which is passed into mmap() and mprotect() in the prot field
- VM_SAO in vma->vm_flags, and
- _PAGE_SAO, the combination of WIMG bits in the pte that enables strong
access ordering for the page.
Signed-off-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/include/asm-powerpc/mman.h b/include/asm-powerpc/mman.h
index 24cf664..0c46bf2 100644
--- a/include/asm-powerpc/mman.h
+++ b/include/asm-powerpc/mman.h
@@ -10,6 +10,8 @@
* 2 of the License, or (at your option) any later version.
*/
+#define PROT_SAO 0x10 /* Strong Access Ordering */
+
#define MAP_RENAME MAP_ANONYMOUS /* In SunOS terminology */
#define MAP_NORESERVE 0x40 /* don't reserve swap pages */
#define MAP_LOCKED 0x80
diff --git a/include/asm-powerpc/pgtable-ppc64.h b/include/asm-powerpc/pgtable-ppc64.h
index b2754d4..d09599c 100644
--- a/include/asm-powerpc/pgtable-ppc64.h
+++ b/include/asm-powerpc/pgtable-ppc64.h
@@ -93,6 +93,9 @@
#define _PAGE_RW 0x0200 /* software: user write access allowed */
#define _PAGE_BUSY 0x0800 /* software: PTE & hash are busy */
+/* Strong Access Ordering */
+#define _PAGE_SAO (_PAGE_WRITETHRU | _PAGE_NO_CACHE | _PAGE_COHERENT)
+
#define _PAGE_BASE (_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_COHERENT)
#define _PAGE_WRENABLE (_PAGE_RW | _PAGE_DIRTY)
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 586a943..6891844 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -108,6 +108,7 @@
#define VM_CAN_NONLINEAR 0x08000000 /* Has ->fault & does nonlinear pages */
#define VM_MIXEDMAP 0x10000000 /* Can contain "struct page" and pure PFN pages */
+#define VM_SAO 0x20000000 /* Strong Access Ordering (powerpc) */
#ifndef VM_STACK_DEFAULT_FLAGS /* arch can override this */
#define VM_STACK_DEFAULT_FLAGS VM_DATA_DEFAULT_FLAGS