From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751977Ab2DCFha (ORCPT ); Tue, 3 Apr 2012 01:37:30 -0400 Received: from mail-bk0-f46.google.com ([209.85.214.46]:53445 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751548Ab2DCFh3 (ORCPT ); Tue, 3 Apr 2012 01:37:29 -0400 Message-ID: <4F7A8C94.3040708@openvz.org> Date: Tue, 03 Apr 2012 09:37:24 +0400 From: Konstantin Khlebnikov User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.2) Gecko/20120217 Firefox/10.0.2 Iceape/2.7.2 MIME-Version: 1.0 To: Suresh Siddha CC: Konstantin Khlebnikov , "linux-mm@kvack.org" , Andrew Morton , "linux-kernel@vger.kernel.org" , Andi Kleen , Pallipadi Venkatesh , Ingo Molnar , "H. Peter Anvin" , Linus Torvalds , Nick Piggin Subject: Re: [x86 PAT PATCH 1/2] x86, pat: remove the dependency on 'vm_pgoff' in track/untrack pfn vma routines References: <20120331170947.7773.46399.stgit@zurg> <1333413969-30761-1-git-send-email-suresh.b.siddha@intel.com> <1333413969-30761-2-git-send-email-suresh.b.siddha@intel.com> In-Reply-To: <1333413969-30761-2-git-send-email-suresh.b.siddha@intel.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Suresh Siddha wrote: > 'pfn' argument for track_pfn_vma_new() can be used for reserving the attribute > for the pfn range. No need to depend on 'vm_pgoff' > > Similarly, untrack_pfn_vma() can depend on the 'pfn' argument if it > is non-zero or can use follow_phys() to get the starting value of the pfn > range. > > Also the non zero 'size' argument can be used instead of recomputing > it from vma. > > This cleanup also prepares the ground for the track/untrack pfn vma routines > to take over the ownership of setting PAT specific vm_flag in the 'vma'. > > Signed-off-by: Suresh Siddha > Cc: Venkatesh Pallipadi > Cc: Konstantin Khlebnikov > --- > arch/x86/mm/pat.c | 30 +++++++++++++++++------------- > 1 files changed, 17 insertions(+), 13 deletions(-) > > diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c > index f6ff57b..617f42b 100644 > --- a/arch/x86/mm/pat.c > +++ b/arch/x86/mm/pat.c > @@ -693,14 +693,10 @@ int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot, > unsigned long pfn, unsigned long size) > { > unsigned long flags; > - resource_size_t paddr; > - unsigned long vma_size = vma->vm_end - vma->vm_start; > > - if (is_linear_pfn_mapping(vma)) { > - /* reserve the whole chunk starting from vm_pgoff */ > - paddr = (resource_size_t)vma->vm_pgoff<< PAGE_SHIFT; > - return reserve_pfn_range(paddr, vma_size, prot, 0); > - } > + /* reserve the whole chunk starting from pfn */ > + if (is_linear_pfn_mapping(vma)) > + return reserve_pfn_range(pfn, size, prot, 0); you mix here pfn and paddr: old code passes paddr as first argument of reserve_pfn_range(). > > if (!pat_enabled) > return 0; > @@ -716,20 +712,28 @@ int track_pfn_vma_new(struct vm_area_struct *vma, pgprot_t *prot, > /* > * untrack_pfn_vma is called while unmapping a pfnmap for a region. > * untrack can be called for a specific region indicated by pfn and size or > - * can be for the entire vma (in which case size can be zero). > + * can be for the entire vma (in which case pfn, size are zero). > */ > void untrack_pfn_vma(struct vm_area_struct *vma, unsigned long pfn, > unsigned long size) > { > resource_size_t paddr; > - unsigned long vma_size = vma->vm_end - vma->vm_start; > + unsigned long prot; > > - if (is_linear_pfn_mapping(vma)) { > - /* free the whole chunk starting from vm_pgoff */ > - paddr = (resource_size_t)vma->vm_pgoff<< PAGE_SHIFT; > - free_pfn_range(paddr, vma_size); > + if (!is_linear_pfn_mapping(vma)) > return; > + > + /* free the chunk starting from pfn or the whole chunk */ > + paddr = (resource_size_t)pfn; > + if (!paddr&& !size) { > + if (follow_phys(vma, vma->vm_start, 0,&prot,&paddr)) { > + WARN_ON_ONCE(1); > + return; > + } > + > + size = vma->vm_end - vma->vm_start; > } > + free_pfn_range(paddr, size); > } > > pgprot_t pgprot_writecombine(pgprot_t prot)