Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761034AbZCMRGx (ORCPT ); Fri, 13 Mar 2009 13:06:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759913AbZCMRB2 (ORCPT ); Fri, 13 Mar 2009 13:01:28 -0400 Received: from gw.goop.org ([64.81.55.164]:57425 "EHLO abulafia.goop.org" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1759814AbZCMRB0 (ORCPT ); Fri, 13 Mar 2009 13:01:26 -0400 From: Jeremy Fitzhardinge To: "H. Peter Anvin" Cc: the arch/x86 maintainers , Linux Kernel Mailing List , Xen-devel , David Airlie , Jeremy Fitzhardinge Subject: [PATCH 25/27] x86: define arch_vm_get_page_prot to set _PAGE_IOMAP on VM_IO vmas Date: Fri, 13 Mar 2009 10:00:10 -0700 Message-Id: <1236963612-14287-26-git-send-email-jeremy@goop.org> X-Mailer: git-send-email 1.6.0.6 In-Reply-To: <1236963612-14287-1-git-send-email-jeremy@goop.org> References: <1236963612-14287-1-git-send-email-jeremy@goop.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2016 Lines: 59 From: Jeremy Fitzhardinge Set _PAGE_IOMAP in ptes mapping a VM_IO vma. This says that the mapping is of a real piece of physical hardware, and not just system memory. Xen, in particular, uses to this to inhibit the normal pfn->mfn conversion that would normally happen - in other words, treat the address directly as a machine physical address without converting it from pseudo-physical. Signed-off-by: Jeremy Fitzhardinge Cc: David Airlie --- arch/x86/include/asm/pgtable.h | 3 +++ arch/x86/mm/pgtable.c | 10 ++++++++++ 2 files changed, 13 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index d37e55e..d7cbfaa 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -391,6 +391,9 @@ static inline unsigned long pages_to_mb(unsigned long npg) #define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \ remap_pfn_range(vma, vaddr, pfn, size, prot) +#define arch_vm_get_page_prot arch_vm_get_page_prot +extern pgprot_t arch_vm_get_page_prot(unsigned vm_flags); + #if PAGETABLE_LEVELS > 2 static inline int pud_none(pud_t pud) { diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 7a4d6ee..d9da313 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -6,6 +6,16 @@ #define PGALLOC_GFP GFP_KERNEL | __GFP_NOTRACK | __GFP_REPEAT | __GFP_ZERO +pgprot_t arch_vm_get_page_prot(unsigned vm_flags) +{ + pgprot_t ret = __pgprot(0); + + if (vm_flags & VM_IO) + ret = __pgprot(_PAGE_IOMAP); + + return ret; +} + pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) { return (pte_t *)__get_free_page(PGALLOC_GFP); -- 1.6.0.6 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/