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 24cf664a829564ebeb9e8a6968a1ad5c2581265e..0c46bf2c7d5fe6557272cc51d0444aa72b4a438a 100644 (file)
--- 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 b2754d46be4423519e73f832b3e69b86ac2bf9d8..d09599cccb353c08f5883c6e0ca2fa5d61b5142a 100644 (file)
--- 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 586a943cab018647da208582bc1f19e0dc485f1d..689184446fc66ff8fd66126d0e0fa24e8d0203bc 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -108,6 +108,7 @@ extern unsigned int kobjsize(const void *objp);
 
 #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