From a1f242ff460e4b50a045fa237c3c56cce9eabf83 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 23 Jul 2008 21:27:08 -0700 Subject: powerpc ioremap_prot This adds ioremap_prot and pte_pgprot() so that one can extract protection bits from a PTE and use them to ioremap_prot() (in order to support ptrace of VM_IO | VM_PFNMAP as per Rik's patch). This moves a couple of flag checks around in the ioremap implementations of arch/powerpc. There's a side effect of allowing non-cacheable and non-guarded mappings on ppc32 which before would always have _PAGE_GUARDED set whenever _PAGE_NO_CACHE is. (standard ioremap will still set _PAGE_GUARDED, but ioremap_prot will be capable of setting such a non guarded mapping). Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Rik van Riel Cc: Dave Airlie Cc: Hugh Dickins Cc: Paul Mackerras Cc: Arnd Bergmann Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-powerpc/pgtable-ppc32.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'include/asm-powerpc/pgtable-ppc32.h') diff --git a/include/asm-powerpc/pgtable-ppc32.h b/include/asm-powerpc/pgtable-ppc32.h index 3a96d001cb75..bdbab72f3ebc 100644 --- a/include/asm-powerpc/pgtable-ppc32.h +++ b/include/asm-powerpc/pgtable-ppc32.h @@ -395,6 +395,12 @@ extern int icache_44x_need_flush; #ifndef _PAGE_EXEC #define _PAGE_EXEC 0 #endif +#ifndef _PAGE_ENDIAN +#define _PAGE_ENDIAN 0 +#endif +#ifndef _PAGE_COHERENT +#define _PAGE_COHERENT 0 +#endif #ifndef _PMD_PRESENT_MASK #define _PMD_PRESENT_MASK _PMD_PRESENT #endif @@ -405,6 +411,12 @@ extern int icache_44x_need_flush; #define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY) + +#define PAGE_PROT_BITS __pgprot(_PAGE_GUARDED | _PAGE_COHERENT | _PAGE_NO_CACHE | \ + _PAGE_WRITETHRU | _PAGE_ENDIAN | \ + _PAGE_USER | _PAGE_ACCESSED | \ + _PAGE_RW | _PAGE_HWWRITE | _PAGE_DIRTY | \ + _PAGE_EXEC | _PAGE_HWEXEC) /* * Note: the _PAGE_COHERENT bit automatically gets set in the hardware * PTE if CONFIG_SMP is defined (hash_page does this); there is no need @@ -538,6 +550,10 @@ static inline pte_t pte_mkyoung(pte_t pte) { pte_val(pte) |= _PAGE_ACCESSED; return pte; } static inline pte_t pte_mkspecial(pte_t pte) { return pte; } +static inline unsigned long pte_pgprot(pte_t pte) +{ + return __pgprot(pte_val(pte)) & PAGE_PROT_BITS; +} static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) { -- cgit v1.2.3