From patchwork Sat Dec 8 17:36:56 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 53406 Received: from vger.kernel.org ([209.132.180.67]) by www.linuxtv.org with esmtp (Exim 4.84_2) (envelope-from ) id 1gVgXc-0003WR-HV; Sat, 08 Dec 2018 17:37:24 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726277AbeLHRhW (ORCPT + 1 other); Sat, 8 Dec 2018 12:37:22 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:42952 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726174AbeLHRhS (ORCPT ); Sat, 8 Dec 2018 12:37:18 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From :Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help: List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=yQfz+QIKzBBrHDZauPcpkKETGukfKkWCPbz32A1mz2E=; b=qpQidi4LvpVTFIIWdBieSHClf2 4+6gvC6DoGU3SNXpt+SwVkx7wEM4EVi4e9S55PRApLTxE27jySZhyIKExqs1emhqZ7l5ZG4DmKOSk wuGpyRf8aG0Q2WCBvGNHHuFztFjWFs2ldvuuC4Gwy7ljpxUt2Qa7X2BsvIX3b7eA/Y1ES5QTrReRg gim2H3f7xia9oGzumdJ7OVAAkH7QBjLc3s0apWhcVjArkC6IjoPKAi88PW9onWVKfb1yI1dhXrq5p 7PVBC7/JHMxlWHwGWZl93fIusgOWXFfMw0Dd76nsjj6u52fUAseYX4DZxlnibukVM5ThXtTnYpCaS hKnrC5Iw==; Received: from [184.48.100.57] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1gVgXI-000546-6l; Sat, 08 Dec 2018 17:37:04 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org Cc: Robin Murphy , Vineet Gupta , "Matwey V. Kornilov" , Laurent Pinchart , linux-snps-arc@lists.infradead.org, Ezequiel Garcia , linux-media@vger.kernel.org, linux-arm-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, sparclinux@vger.kernel.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, linux-mips@vger.kernel.org Subject: [PATCH 04/10] arm: implement DMA_ATTR_NON_CONSISTENT Date: Sat, 8 Dec 2018 09:36:56 -0800 Message-Id: <20181208173702.15158-5-hch@lst.de> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181208173702.15158-1-hch@lst.de> References: <20181208173702.15158-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org For the iommu ops we can just use the implementaton for DMA coherent devices. For the regular ops we need mix and match a bit so that we either use the CMA allocator without remapping, but with a special error handling case for highmem pages, or the simple allocator. Signed-off-by: Christoph Hellwig --- arch/arm/mm/dma-mapping.c | 49 ++++++++++++++++++++++++++++----------- 1 file changed, 35 insertions(+), 14 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 2cfb17bad1e6..b3b66b41c450 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -49,6 +49,7 @@ struct arm_dma_alloc_args { const void *caller; bool want_vaddr; int coherent_flag; + bool nonconsistent_flag; }; struct arm_dma_free_args { @@ -57,6 +58,7 @@ struct arm_dma_free_args { void *cpu_addr; struct page *page; bool want_vaddr; + bool nonconsistent_flag; }; #define NORMAL 0 @@ -348,7 +350,8 @@ static void __dma_free_buffer(struct page *page, size_t size) static void *__alloc_from_contiguous(struct device *dev, size_t size, pgprot_t prot, struct page **ret_page, const void *caller, bool want_vaddr, - int coherent_flag, gfp_t gfp); + int coherent_flag, bool nonconsistent_flag, + gfp_t gfp); static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp, pgprot_t prot, struct page **ret_page, @@ -405,7 +408,7 @@ static int __init atomic_pool_init(void) if (dev_get_cma_area(NULL)) ptr = __alloc_from_contiguous(NULL, atomic_pool_size, prot, &page, atomic_pool_init, true, NORMAL, - GFP_KERNEL); + false, GFP_KERNEL); else ptr = __alloc_remap_buffer(NULL, atomic_pool_size, gfp, prot, &page, atomic_pool_init, true); @@ -579,7 +582,8 @@ static int __free_from_pool(void *start, size_t size) static void *__alloc_from_contiguous(struct device *dev, size_t size, pgprot_t prot, struct page **ret_page, const void *caller, bool want_vaddr, - int coherent_flag, gfp_t gfp) + int coherent_flag, bool nonconsistent_flag, + gfp_t gfp) { unsigned long order = get_order(size); size_t count = size >> PAGE_SHIFT; @@ -595,12 +599,16 @@ static void *__alloc_from_contiguous(struct device *dev, size_t size, if (!want_vaddr) goto out; + if (nonconsistent_flag) { + if (PageHighMem(page)) + goto fail; + goto out; + } + if (PageHighMem(page)) { ptr = __dma_alloc_remap(page, size, GFP_KERNEL, prot, caller); - if (!ptr) { - dma_release_from_contiguous(dev, page, count); - return NULL; - } + if (!ptr) + goto fail; } else { __dma_remap(page, size, prot); ptr = page_address(page); @@ -609,12 +617,15 @@ static void *__alloc_from_contiguous(struct device *dev, size_t size, out: *ret_page = page; return ptr; + fail: + dma_release_from_contiguous(dev, page, count); + return NULL; } static void __free_from_contiguous(struct device *dev, struct page *page, - void *cpu_addr, size_t size, bool want_vaddr) + void *cpu_addr, size_t size, bool remapped) { - if (want_vaddr) { + if (remapped) { if (PageHighMem(page)) __dma_free_remap(cpu_addr, size); else @@ -635,7 +646,11 @@ static void *__alloc_simple_buffer(struct device *dev, size_t size, gfp_t gfp, struct page **ret_page) { struct page *page; - /* __alloc_simple_buffer is only called when the device is coherent */ + /* + * __alloc_simple_buffer is only called when the device is coherent, + * or if the caller explicitly asked for an allocation that is not + * consistent. + */ page = __dma_alloc_buffer(dev, size, gfp, COHERENT); if (!page) return NULL; @@ -667,13 +682,15 @@ static void *cma_allocator_alloc(struct arm_dma_alloc_args *args, return __alloc_from_contiguous(args->dev, args->size, args->prot, ret_page, args->caller, args->want_vaddr, args->coherent_flag, + args->nonconsistent_flag, args->gfp); } static void cma_allocator_free(struct arm_dma_free_args *args) { __free_from_contiguous(args->dev, args->page, args->cpu_addr, - args->size, args->want_vaddr); + args->size, + args->want_vaddr || args->nonconsistent_flag); } static struct arm_dma_allocator cma_allocator = { @@ -735,6 +752,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, .caller = caller, .want_vaddr = ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0), .coherent_flag = is_coherent ? COHERENT : NORMAL, + .nonconsistent_flag = (attrs & DMA_ATTR_NON_CONSISTENT), }; #ifdef CONFIG_DMA_API_DEBUG @@ -773,7 +791,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, if (cma) buf->allocator = &cma_allocator; - else if (is_coherent) + else if (is_coherent || (attrs & DMA_ATTR_NON_CONSISTENT)) buf->allocator = &simple_allocator; else if (allowblock) buf->allocator = &remap_allocator; @@ -874,6 +892,7 @@ static void __arm_dma_free(struct device *dev, size_t size, void *cpu_addr, .cpu_addr = cpu_addr, .page = page, .want_vaddr = ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0), + .nonconsistent_flag = (attrs & DMA_ATTR_NON_CONSISTENT), }; buf = arm_dma_buffer_find(cpu_addr); @@ -1562,7 +1581,8 @@ static void *__arm_iommu_alloc_attrs(struct device *dev, size_t size, static void *arm_iommu_alloc_attrs(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, unsigned long attrs) { - return __arm_iommu_alloc_attrs(dev, size, handle, gfp, attrs, NORMAL); + return __arm_iommu_alloc_attrs(dev, size, handle, gfp, attrs, + (attrs & DMA_ATTR_NON_CONSISTENT) ? COHERENT : NORMAL); } static void *arm_coherent_iommu_alloc_attrs(struct device *dev, size_t size, @@ -1650,7 +1670,8 @@ void __arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr, void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr, dma_addr_t handle, unsigned long attrs) { - __arm_iommu_free_attrs(dev, size, cpu_addr, handle, attrs, NORMAL); + __arm_iommu_free_attrs(dev, size, cpu_addr, handle, attrs, + (attrs & DMA_ATTR_NON_CONSISTENT) ? COHERENT : NORMAL); } void arm_coherent_iommu_free_attrs(struct device *dev, size_t size,