From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 172F2C5CFFE for ; Mon, 10 Dec 2018 16:32:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DAAC320821 for ; Mon, 10 Dec 2018 16:32:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DAAC320821 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728271AbeLJQcO (ORCPT ); Mon, 10 Dec 2018 11:32:14 -0500 Received: from foss.arm.com ([217.140.101.70]:58194 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726649AbeLJQcK (ORCPT ); Mon, 10 Dec 2018 11:32:10 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 41A2C1596; Mon, 10 Dec 2018 08:32:10 -0800 (PST) Received: from [10.1.196.75] (e110467-lin.cambridge.arm.com [10.1.196.75]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 4E9753F6A8; Mon, 10 Dec 2018 08:32:08 -0800 (PST) Subject: Re: [PATCH v3 2/9] arch/arm/mm/dma-mapping.c: Convert to use vm_insert_range To: Souptick Joarder , Andrew Morton , Matthew Wilcox , Michal Hocko , Russell King - ARM Linux , iamjoonsoo.kim@lge.com, treding@nvidia.com, Kees Cook , Marek Szyprowski Cc: linux-kernel@vger.kernel.org, Linux-MM , linux-arm-kernel@lists.infradead.org References: <20181206184103.GA25872@jordon-HP-15-Notebook-PC> From: Robin Murphy Message-ID: <217b80f9-e02c-d02c-3c82-425c550e4ed7@arm.com> Date: Mon, 10 Dec 2018 16:32:06 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-GB Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/12/2018 20:01, Souptick Joarder wrote: > Hi Robin, > > On Fri, Dec 7, 2018 at 12:07 AM Souptick Joarder wrote: >> >> Convert to use vm_insert_range() to map range of kernel >> memory to user vma. >> >> Signed-off-by: Souptick Joarder >> --- >> arch/arm/mm/dma-mapping.c | 21 +++++++-------------- >> 1 file changed, 7 insertions(+), 14 deletions(-) >> >> diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c >> index 661fe48..4eec323 100644 >> --- a/arch/arm/mm/dma-mapping.c >> +++ b/arch/arm/mm/dma-mapping.c >> @@ -1582,31 +1582,24 @@ static int __arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma >> void *cpu_addr, dma_addr_t dma_addr, size_t size, >> unsigned long attrs) >> { >> - unsigned long uaddr = vma->vm_start; >> - unsigned long usize = vma->vm_end - vma->vm_start; >> + unsigned long page_count = vma_pages(vma); >> struct page **pages = __iommu_get_pages(cpu_addr, attrs); >> unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; >> unsigned long off = vma->vm_pgoff; >> + int err; >> >> if (!pages) >> return -ENXIO; >> >> - if (off >= nr_pages || (usize >> PAGE_SHIFT) > nr_pages - off) >> + if (off >= nr_pages || page_count > nr_pages - off) >> return -ENXIO; >> >> pages += off; >> + err = vm_insert_range(vma, vma->vm_start, pages, page_count); > > Just to clarify, do we need to adjust page_count with vma->vm_pgoff as > original code > have not consider it and run the loop for entire range irrespective of > vma->vm_pgoff value ? In this instance, page_count is the size of the VMA, not the size of the pages array itself, so as I understand things this patch is true to the original code as-is. Robin. > >> + if (err) >> + pr_err("Remapping memory failed: %d\n", err); >> >> - do { >> - int ret = vm_insert_page(vma, uaddr, *pages++); >> - if (ret) { >> - pr_err("Remapping memory failed: %d\n", ret); >> - return ret; >> - } >> - uaddr += PAGE_SIZE; >> - usize -= PAGE_SIZE; >> - } while (usize > 0); >> - >> - return 0; >> + return err; >> } >> static int arm_iommu_mmap_attrs(struct device *dev, >> struct vm_area_struct *vma, void *cpu_addr, >> -- >> 1.9.1 >>