Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755328AbdCGMbF (ORCPT ); Tue, 7 Mar 2017 07:31:05 -0500 Received: from foss.arm.com ([217.140.101.70]:46782 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754943AbdCGMao (ORCPT ); Tue, 7 Mar 2017 07:30:44 -0500 From: Vladimir Murzin To: linux-arm-kernel@lists.infradead.org Cc: kbuild-all@01.org, linux-kernel@vger.kernel.org, linux@armlinux.org.uk, akpm@linux-foundation.org, robin.murphy@arm.com, benjamin.gaignard@linaro.org, alexandre.torgue@st.com, sza@esh.hu, Joerg Roedel , Christian Borntraeger , Doug Ledford Subject: [PATCH v2 2/7] dma: Add simple dma_noop_mmap Date: Tue, 7 Mar 2017 11:12:29 +0000 Message-Id: <1488885154-12429-3-git-send-email-vladimir.murzin@arm.com> X-Mailer: git-send-email 2.0.0 In-Reply-To: <1488885154-12429-1-git-send-email-vladimir.murzin@arm.com> References: <1488885154-12429-1-git-send-email-vladimir.murzin@arm.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1693 Lines: 55 This patch adds a simple implementation of mmap to dma_noop_ops. Cc: Joerg Roedel Cc: Christian Borntraeger Cc: Doug Ledford Reported-by: Benjamin Gaignard Tested-by: Benjamin Gaignard Tested-by: Andras Szemzo Tested-by: Alexandre TORGUE Signed-off-by: Vladimir Murzin --- lib/dma-noop.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/lib/dma-noop.c b/lib/dma-noop.c index ff4ef5e..0acc3f6 100644 --- a/lib/dma-noop.c +++ b/lib/dma-noop.c @@ -66,6 +66,26 @@ static int dma_noop_supported(struct device *dev, u64 mask) return 1; } +static int dma_noop_mmap(struct device *dev, struct vm_area_struct *vma, + void *cpu_addr, dma_addr_t dma_addr, size_t size, + unsigned long attrs) +{ + unsigned long user_count = vma_pages(vma); + unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT; + unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr)); + unsigned long off = vma->vm_pgoff; + int ret = -ENXIO; + + if (off < count && user_count <= (count - off)) { + ret = remap_pfn_range(vma, vma->vm_start, + pfn + off, + user_count << PAGE_SHIFT, + vma->vm_page_prot); + } + + return ret; +} + const struct dma_map_ops dma_noop_ops = { .alloc = dma_noop_alloc, .free = dma_noop_free, @@ -73,6 +93,7 @@ const struct dma_map_ops dma_noop_ops = { .map_sg = dma_noop_map_sg, .mapping_error = dma_noop_mapping_error, .dma_supported = dma_noop_supported, + .mmap = dma_noop_mmap, }; EXPORT_SYMBOL(dma_noop_ops); -- 2.0.0