From c7d54842deb1fa357cff75b988275a1c9f259140 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Fri, 29 Apr 2016 23:25:30 +1000 Subject: powerpc/mm: Use _PAGE_READ to indicate Read access This splits the _PAGE_RW bit into _PAGE_READ and _PAGE_WRITE. It also removes the dependency on _PAGE_USER for implying read only. Few things to note here is that, we have read implied with write and execute permission. Hence we should always find _PAGE_READ set on hash pte fault. We still can't switch PROT_NONE to !(_PAGE_RWX). Auto numa depends on marking a prot none pte _PAGE_WRITE. (For more details look at b191f9b106ea "mm: numa: preserve PTE write permissions across a NUMA hinting fault") Cc: Arnd Bergmann Cc: Jeremy Kerr Cc: Frederic Barrat Acked-by: Ian Munsie Signed-off-by: Aneesh Kumar K.V Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/pte-common.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'arch/powerpc/include/asm/pte-common.h') diff --git a/arch/powerpc/include/asm/pte-common.h b/arch/powerpc/include/asm/pte-common.h index 1ec67b043065..9f5dea58b0db 100644 --- a/arch/powerpc/include/asm/pte-common.h +++ b/arch/powerpc/include/asm/pte-common.h @@ -198,3 +198,8 @@ extern unsigned long bad_call_to_PMD_PAGE_SIZE(void); /* Advertise support for _PAGE_SPECIAL */ #define __HAVE_ARCH_PTE_SPECIAL +#ifndef _PAGE_READ +/* if not defined, we should not find _PAGE_WRITE too */ +#define _PAGE_READ 0 +#define _PAGE_WRITE _PAGE_RW +#endif -- cgit