From patchwork Mon Aug 11 23:40:29 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Laura Abbott X-Patchwork-Id: 4710181 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 3E4949F38C for ; Mon, 11 Aug 2014 23:43:20 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 2F6C520136 for ; Mon, 11 Aug 2014 23:43:19 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B2479200E5 for ; Mon, 11 Aug 2014 23:43:17 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XGzDB-0002lO-Rw; Mon, 11 Aug 2014 23:41:09 +0000 Received: from smtp.codeaurora.org ([198.145.11.231]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XGzD2-0002ce-J1 for linux-arm-kernel@lists.infradead.org; Mon, 11 Aug 2014 23:41:01 +0000 Received: from smtp.codeaurora.org (localhost [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 94E08140390; Mon, 11 Aug 2014 23:40:40 +0000 (UTC) Received: by smtp.codeaurora.org (Postfix, from userid 486) id 863DD140391; Mon, 11 Aug 2014 23:40:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 Received: from lauraa-linux1.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: lauraa@smtp.codeaurora.org) by smtp.codeaurora.org (Postfix) with ESMTPSA id 9B5DA140386; Mon, 11 Aug 2014 23:40:39 +0000 (UTC) From: Laura Abbott To: Will Deacon , Catalin Marinas , Russell King , Andrew Morton Subject: [PATCHv7 3/5] common: dma-mapping: Introduce common remapping functions Date: Mon, 11 Aug 2014 16:40:29 -0700 Message-Id: <1407800431-21566-4-git-send-email-lauraa@codeaurora.org> X-Mailer: git-send-email 1.8.2.1 In-Reply-To: <1407800431-21566-1-git-send-email-lauraa@codeaurora.org> References: <1407800431-21566-1-git-send-email-lauraa@codeaurora.org> X-Virus-Scanned: ClamAV using ClamSMTP X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140811_164100_688388_3C62007D X-CRM114-Status: GOOD ( 25.65 ) X-Spam-Score: -0.7 (/) Cc: David Riley , Arnd Bergmann , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Thierry Reding , Ritesh Harjain , Laura Abbott , linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP For architectures without coherent DMA, memory for DMA may need to be remapped with coherent attributes. Factor out the the remapping code from arm and put it in a common location to reduce code duplication. As part of this, the arm APIs are now migrated away from ioremap_page_range to the common APIs which use map_vm_area for remapping. This should be an equivalent change and using map_vm_area is more correct as ioremap_page_range is intended to bring in io addresses into the cpu space and not regular kernel managed memory. Reviewed-by: Catalin Marinas Signed-off-by: Laura Abbott --- arch/arm/mm/dma-mapping.c | 57 +++++--------------------- drivers/base/dma-mapping.c | 68 ++++++++++++++++++++++++++++++++ include/asm-generic/dma-mapping-common.h | 9 +++++ 3 files changed, 86 insertions(+), 48 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 4c88935..f5190ac 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -297,37 +297,19 @@ static void * __dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot, const void *caller) { - struct vm_struct *area; - unsigned long addr; - /* * DMA allocation can be mapped to user space, so lets * set VM_USERMAP flags too. */ - area = get_vm_area_caller(size, VM_ARM_DMA_CONSISTENT | VM_USERMAP, - caller); - if (!area) - return NULL; - addr = (unsigned long)area->addr; - area->phys_addr = __pfn_to_phys(page_to_pfn(page)); - - if (ioremap_page_range(addr, addr + size, area->phys_addr, prot)) { - vunmap((void *)addr); - return NULL; - } - return (void *)addr; + return dma_common_contiguous_remap(page, size, + VM_ARM_DMA_CONSISTENT | VM_USERMAP, + prot, caller); } static void __dma_free_remap(void *cpu_addr, size_t size) { - unsigned int flags = VM_ARM_DMA_CONSISTENT | VM_USERMAP; - struct vm_struct *area = find_vm_area(cpu_addr); - if (!area || (area->flags & flags) != flags) { - WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr); - return; - } - unmap_kernel_range((unsigned long)cpu_addr, size); - vunmap(cpu_addr); + dma_common_free_remap(cpu_addr, size, + VM_ARM_DMA_CONSISTENT | VM_USERMAP); } #define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K @@ -1261,29 +1243,8 @@ static void * __iommu_alloc_remap(struct page **pages, size_t size, gfp_t gfp, pgprot_t prot, const void *caller) { - unsigned int i, nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; - struct vm_struct *area; - unsigned long p; - - area = get_vm_area_caller(size, VM_ARM_DMA_CONSISTENT | VM_USERMAP, - caller); - if (!area) - return NULL; - - area->pages = pages; - area->nr_pages = nr_pages; - p = (unsigned long)area->addr; - - for (i = 0; i < nr_pages; i++) { - phys_addr_t phys = __pfn_to_phys(page_to_pfn(pages[i])); - if (ioremap_page_range(p, p + PAGE_SIZE, phys, prot)) - goto err; - p += PAGE_SIZE; - } - return area->addr; -err: - unmap_kernel_range((unsigned long)area->addr, size); - vunmap(area->addr); + return dma_common_pages_remap(pages, size, + VM_ARM_DMA_CONSISTENT | VM_USERMAP, prot, caller); return NULL; } @@ -1491,8 +1452,8 @@ void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr, } if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) { - unmap_kernel_range((unsigned long)cpu_addr, size); - vunmap(cpu_addr); + dma_common_free_remap(cpu_addr, size, + VM_ARM_DMA_CONSISTENT | VM_USERMAP); } __iommu_remove_mapping(dev, handle, size); diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c index 6cd08e1..1bc46df 100644 --- a/drivers/base/dma-mapping.c +++ b/drivers/base/dma-mapping.c @@ -10,6 +10,8 @@ #include #include #include +#include +#include #include /* @@ -267,3 +269,69 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, return ret; } EXPORT_SYMBOL(dma_common_mmap); + +/* + * remaps an allocated contiguous region into another vm_area. + * Cannot be used in non-sleeping contexts + */ + +void *dma_common_contiguous_remap(struct page *page, size_t size, + unsigned long vm_flags, + pgprot_t prot, const void *caller) +{ + int i; + struct page **pages; + void *ptr; + unsigned long pfn; + + pages = kmalloc(sizeof(struct page *) << get_order(size), GFP_KERNEL); + if (!pages) + return NULL; + + for (i = 0, pfn = page_to_pfn(page); i < (size >> PAGE_SHIFT); i++) + pages[i] = pfn_to_page(pfn + i); + + ptr = dma_common_pages_remap(pages, size, vm_flags, prot, caller); + + kfree(pages); + + return ptr; +} + +/* + * remaps an array of PAGE_SIZE pages into another vm_area + * Cannot be used in non-sleeping contexts + */ +void *dma_common_pages_remap(struct page **pages, size_t size, + unsigned long vm_flags, pgprot_t prot, + const void *caller) +{ + struct vm_struct *area; + + area = get_vm_area_caller(size, vm_flags, caller); + if (!area) + return NULL; + + if (map_vm_area(area, prot, pages)) { + vunmap(area->addr); + return NULL; + } + + return area->addr; +} + +/* + * unmaps a range previously mapped by dma_common_*_remap + */ +void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags) +{ + struct vm_struct *area = find_vm_area(cpu_addr); + + if (!area || (area->flags & vm_flags) != vm_flags) { + WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr); + return; + } + + unmap_kernel_range((unsigned long)cpu_addr, size); + vunmap(cpu_addr); +} diff --git a/include/asm-generic/dma-mapping-common.h b/include/asm-generic/dma-mapping-common.h index de8bf89..a9fd248 100644 --- a/include/asm-generic/dma-mapping-common.h +++ b/include/asm-generic/dma-mapping-common.h @@ -179,6 +179,15 @@ dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, extern int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, dma_addr_t dma_addr, size_t size); +void *dma_common_contiguous_remap(struct page *page, size_t size, + unsigned long vm_flags, + pgprot_t prot, const void *caller); + +void *dma_common_pages_remap(struct page **pages, size_t size, + unsigned long vm_flags, pgprot_t prot, + const void *caller); +void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags); + /** * dma_mmap_attrs - map a coherent DMA allocation into user space * @dev: valid struct device pointer, or NULL for ISA and EISA-like devices