Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756150AbcJ1GEi (ORCPT ); Fri, 28 Oct 2016 02:04:38 -0400 Received: from mga01.intel.com ([192.55.52.88]:8045 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755201AbcJ1GEg (ORCPT ); Fri, 28 Oct 2016 02:04:36 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.31,556,1473145200"; d="scan'208";a="1077061529" Message-ID: <5812E9AE.7010209@intel.com> Date: Fri, 28 Oct 2016 14:01:18 +0800 From: Jike Song User-Agent: Mozilla/5.0 (X11; Linux i686 on x86_64; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Kirti Wankhede CC: alex.williamson@redhat.com, pbonzini@redhat.com, kraxel@redhat.com, cjia@nvidia.com, qemu-devel@nongnu.org, kvm@vger.kernel.org, kevin.tian@intel.com, bjsdjshi@linux.vnet.ibm.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH v10 07/19] vfio iommu type1: Update argument of vaddr_get_pfn() References: <1477517366-27871-1-git-send-email-kwankhede@nvidia.com> <1477517366-27871-8-git-send-email-kwankhede@nvidia.com> <5811EF08.5000602@intel.com> <78a52b28-40c6-076d-030e-6eb4c343d73a@nvidia.com> In-Reply-To: <78a52b28-40c6-076d-030e-6eb4c343d73a@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2428 Lines: 70 On 10/27/2016 08:24 PM, Kirti Wankhede wrote: > > > On 10/27/2016 5:41 PM, Jike Song wrote: >> On 10/27/2016 05:29 AM, Kirti Wankhede wrote: >>> Update arguments of vaddr_get_pfn() to take struct mm_struct *mm as input >>> argument. >>> >>> Signed-off-by: Kirti Wankhede >>> Signed-off-by: Neo Jia >>> Change-Id: I885fd4cd4a9f66f4ee2c1caf58267464ec239f52 >>> --- >>> drivers/vfio/vfio_iommu_type1.c | 25 ++++++++++++++++++------- >>> 1 file changed, 18 insertions(+), 7 deletions(-) >>> >>> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c >>> index 72fee415044a..3d916b965492 100644 >>> --- a/drivers/vfio/vfio_iommu_type1.c >>> +++ b/drivers/vfio/vfio_iommu_type1.c >>> @@ -228,20 +228,31 @@ static int put_pfn(unsigned long pfn, int prot) >>> return 0; >>> } >>> >>> -static int vaddr_get_pfn(unsigned long vaddr, int prot, unsigned long *pfn) >>> +static int vaddr_get_pfn(struct mm_struct *remote_mm, unsigned long vaddr, >>> + int prot, unsigned long *pfn) >>> { >>> struct page *page[1]; >>> struct vm_area_struct *vma; >>> + struct mm_struct *mm = (remote_mm ? remote_mm : current->mm); >>> int ret = -EFAULT; >>> >>> - if (get_user_pages_fast(vaddr, 1, !!(prot & IOMMU_WRITE), page) == 1) { >>> + if (remote_mm) { >>> + down_read(&mm->mmap_sem); >>> + ret = get_user_pages_remote(NULL, mm, vaddr, 1, >>> + !!(prot & IOMMU_WRITE), 0, page, NULL); >> >> Hi Kirti, >> >> It seems that get_user_pages_remote has only 7 args but you somehow gives 8 >> here? >> > > I had tested this patch with linux-next. It has 8 arguments, see mm/gup.c: > > long get_user_pages_remote(struct task_struct *tsk, struct mm_struct *mm, > unsigned long start, unsigned long nr_pages, > int write, int force, struct page **pages, > struct vm_area_struct **vmas) > { > return __get_user_pages_locked(tsk, mm, start, nr_pages, write, > force, > pages, vmas, NULL, false, > FOLL_TOUCH | FOLL_REMOTE); > } > EXPORT_SYMBOL(get_user_pages_remote); It's queer. I checked: https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/tree/mm/gup.c It still has 7 args. I believe you have seen this change somewhere, would you share the repo url and branch name of the linux-next you based on? -- Thanks, Jike