From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lj1-f200.google.com (mail-lj1-f200.google.com [209.85.208.200]) by kanga.kvack.org (Postfix) with ESMTP id F3AA88E0004 for ; Sat, 8 Dec 2018 14:58:05 -0500 (EST) Received: by mail-lj1-f200.google.com with SMTP id p65-v6so1899008ljb.16 for ; Sat, 08 Dec 2018 11:58:05 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id k4-v6sor4300933ljc.11.2018.12.08.11.58.04 for (Google Transport Security); Sat, 08 Dec 2018 11:58:04 -0800 (PST) MIME-Version: 1.0 References: <20181206184103.GA25872@jordon-HP-15-Notebook-PC> In-Reply-To: <20181206184103.GA25872@jordon-HP-15-Notebook-PC> From: Souptick Joarder Date: Sun, 9 Dec 2018 01:31:40 +0530 Message-ID: Subject: Re: [PATCH v3 2/9] arch/arm/mm/dma-mapping.c: Convert to use vm_insert_range Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Matthew Wilcox , Michal Hocko , Russell King - ARM Linux , robin.murphy@arm.com, 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 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 ? > + 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 >