From patchwork Tue Nov 24 15:38:43 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ricardo Ribalda X-Patchwork-Id: 11929241 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 378F6C64E75 for ; Tue, 24 Nov 2020 15:39:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0D822067C for ; Tue, 24 Nov 2020 15:39:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="P/Yhlw5T" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389835AbgKXPiy (ORCPT ); Tue, 24 Nov 2020 10:38:54 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53998 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389823AbgKXPiv (ORCPT ); Tue, 24 Nov 2020 10:38:51 -0500 Received: from mail-wr1-x442.google.com (mail-wr1-x442.google.com [IPv6:2a00:1450:4864:20::442]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57298C0613D6 for ; Tue, 24 Nov 2020 07:38:51 -0800 (PST) Received: by mail-wr1-x442.google.com with SMTP id p8so22779849wrx.5 for ; Tue, 24 Nov 2020 07:38:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=HML93bM0Bc4n5YHvmGElcbvPwZfiGcvKE6k2Cpvki30=; b=P/Yhlw5TgpxeGby9pjaEmYM0kGqLCsDDYBbhyLuTlFded/Q5ZQRlZ84NfRlykzbYH1 DkVUEyabfDMDks59dR0b4BJYzFtC7c9ApMtGMz0bO5Hu7ZMt+S74Y94J6gZNfEWSV4ge MnpSsvnZ0GngUkTv8BCpKHurEO5uF9oK2zb5g= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=HML93bM0Bc4n5YHvmGElcbvPwZfiGcvKE6k2Cpvki30=; b=K6HJxZbdeDd5bPnctn+bUScRGojZV6tyPtgIq+KeQABJk3xbhSePzDzwc95p1HPL1V ro5U2ujLSlI56Xq2taDw6c+zbTYnSdb/VNRJkIY9z3R5MsV5hui6oaaJLlWu29+oiwXk n6ljPgpOvn9aLSMJwL6a+6drrKZUr2ldsNYP/niLCLMgzqBV09CVyFGqNAB0tHCFaYuG CIxhmlqdbpAN0KREOQEHuA4d4cfrwK6K5L/j7KZvVDkPVbCLz5pP/L55sLCoPEt8ZSN7 8oM5PrZ3coW1fp/Q2APm2cBziNzYqGC+Tpr24ZTpecfBfcuH53PIlc56dSMjlyOyTkB7 9uxQ== X-Gm-Message-State: AOAM5337KDr4xR8E++QjjA1kyaTq3x7atWGzBO/W8ggnHO5Q+9d9xqow iyQdT314J7uct3Z67Dp+Ef4cyA== X-Google-Smtp-Source: ABdhPJyr+m/OvVN8bOtfmxzP/EzSgR9DeGgRdBRvSfGr9+vxnRk4Tg52DdcdCEyGndX/SxXL7AVijg== X-Received: by 2002:a5d:44c1:: with SMTP id z1mr5836653wrr.375.1606232330021; Tue, 24 Nov 2020 07:38:50 -0800 (PST) Received: from alco.lan ([80.71.134.83]) by smtp.gmail.com with ESMTPSA id 25sm5814752wmk.19.2020.11.24.07.38.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 24 Nov 2020 07:38:49 -0800 (PST) From: Ricardo Ribalda To: Christoph Hellwig , Mauro Carvalho Chehab , Marek Szyprowski , IOMMU DRIVERS , Joerg Roedel , Robin Murphy , Linux Doc Mailing List , Linux Kernel Mailing List , Linux Media Mailing List , Tomasz Figa , Sergey Senozhatsky Subject: [PATCH 4/6] WIP: add a dma_alloc_contiguous API Date: Tue, 24 Nov 2020 16:38:43 +0100 Message-Id: <20201124153845.132207-4-ribalda@chromium.org> X-Mailer: git-send-email 2.29.2.454.gaff20da3a2-goog In-Reply-To: <20201124153845.132207-1-ribalda@chromium.org> References: <20201124153845.132207-1-ribalda@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Christoph Hellwig Add a new API that returns a virtually non-contigous array of pages and dma address. This API is only implemented for dma-iommu and will not be implemented for non-iommu DMA API instances that have to allocate contiguous memory. It is up to the caller to check if the API is available. The intent is that media drivers can use this API if either: - no kernel mapping or only temporary kernel mappings are required. That is as a better replacement for DMA_ATTR_NO_KERNEL_MAPPING - a kernel mapping is required for cached and DMA mapped pages, but the driver also needs the pages to e.g. map them to userspace. In that sense it is a replacement for some aspects of the recently removed and never fully implemented DMA_ATTR_NON_CONSISTENT Signed-off-by: Christoph Hellwig --- drivers/iommu/dma-iommu.c | 73 +++++++++++++++++++++++++------------ include/linux/dma-map-ops.h | 4 ++ include/linux/dma-mapping.h | 5 +++ kernel/dma/mapping.c | 35 ++++++++++++++++++ 4 files changed, 93 insertions(+), 24 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index a2fb92de7e3d..2e72fe1b9c3b 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -564,23 +564,12 @@ static struct page **__iommu_dma_alloc_pages(struct device *dev, return pages; } -/** - * iommu_dma_alloc_remap - Allocate and map a buffer contiguous in IOVA space - * @dev: Device to allocate memory for. Must be a real device - * attached to an iommu_dma_domain - * @size: Size of buffer in bytes - * @dma_handle: Out argument for allocated DMA handle - * @gfp: Allocation flags - * @prot: pgprot_t to use for the remapped mapping - * @attrs: DMA attributes for this allocation - * - * If @size is less than PAGE_SIZE, then a full CPU page will be allocated, +/* + * If size is less than PAGE_SIZE, then a full CPU page will be allocated, * but an IOMMU which supports smaller pages might not map the whole thing. - * - * Return: Mapped virtual address, or NULL on failure. */ -static void *iommu_dma_alloc_remap(struct device *dev, size_t size, - dma_addr_t *dma_handle, gfp_t gfp, pgprot_t prot, +static struct page **__iommu_dma_alloc_noncontiguous(struct device *dev, + size_t size, dma_addr_t *dma_handle, gfp_t gfp, pgprot_t prot, unsigned long attrs) { struct iommu_domain *domain = iommu_get_dma_domain(dev); @@ -592,7 +581,6 @@ static void *iommu_dma_alloc_remap(struct device *dev, size_t size, struct page **pages; struct sg_table sgt; dma_addr_t iova; - void *vaddr; *dma_handle = DMA_MAPPING_ERROR; @@ -635,17 +623,10 @@ static void *iommu_dma_alloc_remap(struct device *dev, size_t size, < size) goto out_free_sg; - vaddr = dma_common_pages_remap(pages, size, prot, - __builtin_return_address(0)); - if (!vaddr) - goto out_unmap; - *dma_handle = iova; sg_free_table(&sgt); - return vaddr; + return pages; -out_unmap: - __iommu_dma_unmap(dev, iova, size); out_free_sg: sg_free_table(&sgt); out_free_iova: @@ -655,6 +636,46 @@ static void *iommu_dma_alloc_remap(struct device *dev, size_t size, return NULL; } +static void *iommu_dma_alloc_remap(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, pgprot_t prot, + unsigned long attrs) +{ + struct page **pages; + void *vaddr; + + pages = __iommu_dma_alloc_noncontiguous(dev, size, dma_handle, gfp, + prot, attrs); + if (!pages) + return NULL; + vaddr = dma_common_pages_remap(pages, size, prot, + __builtin_return_address(0)); + if (!vaddr) + goto out_unmap; + return vaddr; + +out_unmap: + __iommu_dma_unmap(dev, *dma_handle, size); + __iommu_dma_free_pages(pages, PAGE_ALIGN(size) >> PAGE_SHIFT); + return NULL; +} + +#ifdef CONFIG_DMA_REMAP +static struct page **iommu_dma_alloc_noncontiguous(struct device *dev, + size_t size, dma_addr_t *dma_handle, gfp_t gfp, + unsigned long attrs) +{ + return __iommu_dma_alloc_noncontiguous(dev, size, dma_handle, gfp, + PAGE_KERNEL, attrs); +} + +static void iommu_dma_free_noncontiguous(struct device *dev, size_t size, + struct page **pages, dma_addr_t dma_handle) +{ + __iommu_dma_unmap(dev, dma_handle, size); + __iommu_dma_free_pages(pages, PAGE_ALIGN(size) >> PAGE_SHIFT); +} +#endif + static void iommu_dma_sync_single_for_cpu(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir) { @@ -1109,6 +1130,10 @@ static const struct dma_map_ops iommu_dma_ops = { .free = iommu_dma_free, .alloc_pages = dma_common_alloc_pages, .free_pages = dma_common_free_pages, +#ifdef CONFIG_DMA_REMAP + .alloc_noncontiguous = iommu_dma_alloc_noncontiguous, + .free_noncontiguous = iommu_dma_free_noncontiguous, +#endif .mmap = iommu_dma_mmap, .get_sgtable = iommu_dma_get_sgtable, .map_page = iommu_dma_map_page, diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index 3d1f91464bcf..3cc313678d42 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -22,6 +22,10 @@ struct dma_map_ops { gfp_t gfp); void (*free_pages)(struct device *dev, size_t size, struct page *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir); + struct page **(*alloc_noncontiguous)(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); + void (*free_noncontiguous)(struct device *dev, size_t size, + struct page **pages, dma_addr_t dma_handle); int (*mmap)(struct device *, struct vm_area_struct *, void *, dma_addr_t, size_t, unsigned long attrs); diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 956151052d45..e1b4cb1d2e55 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -267,6 +267,11 @@ void *dma_alloc_noncoherent(struct device *dev, size_t size, dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp); void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr, dma_addr_t dma_handle, enum dma_data_direction dir); +bool dma_can_alloc_noncontiguous(struct device *dev); +struct page **dma_alloc_noncontiguous(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); +void dma_free_noncontiguous(struct device *dev, size_t size, + struct page **pages, dma_addr_t dma_handle); static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr, size_t size, enum dma_data_direction dir, unsigned long attrs) diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index d3032513c54b..770c2f66512d 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -530,6 +530,41 @@ void dma_free_noncoherent(struct device *dev, size_t size, void *vaddr, } EXPORT_SYMBOL_GPL(dma_free_noncoherent); +bool dma_can_alloc_noncontiguous(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + return ops && ops->free_noncontiguous; +} +EXPORT_SYMBOL_GPL(dma_can_alloc_noncontiguous); + +struct page **dma_alloc_noncontiguous(struct device *dev, size_t size, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (WARN_ON_ONCE(!dma_can_alloc_noncontiguous(dev))) + return NULL; + if (attrs & ~DMA_ATTR_ALLOC_SINGLE_PAGES) { + dev_warn(dev, "invalid flags (0x%lx) for %s\n", + attrs, __func__); + return NULL; + } + return ops->alloc_noncontiguous(dev, size, dma_handle, gfp, attrs); +} +EXPORT_SYMBOL_GPL(dma_alloc_noncontiguous); + +void dma_free_noncontiguous(struct device *dev, size_t size, + struct page **pages, dma_addr_t dma_handle) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (WARN_ON_ONCE(!dma_can_alloc_noncontiguous(dev))) + return; + ops->free_noncontiguous(dev, size, pages, dma_handle); +} +EXPORT_SYMBOL_GPL(dma_free_noncontiguous); + int dma_supported(struct device *dev, u64 mask) { const struct dma_map_ops *ops = get_dma_ops(dev);