From patchwork Thu May 13 22:31:57 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 12256675 X-Patchwork-Delegate: bhelgaas@google.com 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,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 C9220C4161D for ; Thu, 13 May 2021 22:32:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A861D61435 for ; Thu, 13 May 2021 22:32:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233719AbhEMWdi (ORCPT ); Thu, 13 May 2021 18:33:38 -0400 Received: from ale.deltatee.com ([204.191.154.188]:59086 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233644AbhEMWdb (ORCPT ); Thu, 13 May 2021 18:33:31 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=deltatee.com; s=20200525; h=Subject:MIME-Version:References:In-Reply-To: Message-Id:Date:Cc:To:From:content-disposition; bh=+6LOZREMQdKcKU9+XV49PWq6lyu+rsgxO5mlOPuR0D0=; b=gopNy0pdi7kPMUBu2VOUSrNjnr nDk/YrjZZaemYWUi87naDC/XBiayhz91eTft5y7LVS4LvVe9pisHmjLGpi7M8+AZFgWIyKgREdkwi sZQ2TgGIfQJHj62k06it7hWXTFkkLLIsRrguBUo066VTlT47L8xrg8PgwlTQ3gceFDa/mOKc5qvn6 hvbNNdNi/06xG0iWomhRB2KDNnMFfgU/7jANjA4coPGrDzbN06hio/bAhnbInbuQ2h6YAmyKD5wkC E3WVjODcBj55dfJ3X6vMJWKxNwShCvY6ZWrPqq2+x2e5bY2LVDh7u7ieA2RLWabpOKcWRcEqkNnMA qjt+4YZw==; Received: from cgy1-donard.priv.deltatee.com ([172.16.1.31]) by ale.deltatee.com with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lhJsS-0000nC-4u; Thu, 13 May 2021 16:32:20 -0600 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.92) (envelope-from ) id 1lhJsI-0001TE-3i; Thu, 13 May 2021 16:32:10 -0600 From: Logan Gunthorpe To: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org Cc: Stephen Bates , Christoph Hellwig , Dan Williams , Jason Gunthorpe , =?utf-8?q?Christian_K=C3=B6nig?= , John Hubbard , Don Dutile , Matthew Wilcox , Daniel Vetter , Jakowski Andrzej , Minturn Dave B , Jason Ekstrand , Dave Hansen , Xiong Jianxin , Bjorn Helgaas , Ira Weiny , Robin Murphy , Logan Gunthorpe Date: Thu, 13 May 2021 16:31:57 -0600 Message-Id: <20210513223203.5542-17-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210513223203.5542-1-logang@deltatee.com> References: <20210513223203.5542-1-logang@deltatee.com> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 172.16.1.31 X-SA-Exim-Rcpt-To: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, sbates@raithlin.com, hch@lst.de, jgg@ziepe.ca, christian.koenig@amd.com, jhubbard@nvidia.com, ddutile@redhat.com, willy@infradead.org, daniel.vetter@ffwll.ch, jason@jlekstrand.net, dave.hansen@linux.intel.com, helgaas@kernel.org, dan.j.williams@intel.com, andrzej.jakowski@intel.com, dave.b.minturn@intel.com, jianxin.xiong@intel.com, ira.weiny@intel.com, robin.murphy@arm.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [PATCH v2 16/22] dma-mapping: Add flags to dma_map_ops to indicate PCI P2PDMA support X-SA-Exim-Version: 4.2.1 (built Wed, 08 May 2019 21:11:16 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add a flags member to the dma_map_ops structure with one flag to indicate support for PCI P2PDMA. Also, add a helper to check if a device supports PCI P2PDMA. Signed-off-by: Logan Gunthorpe --- include/linux/dma-map-ops.h | 10 ++++++++++ include/linux/dma-mapping.h | 5 +++++ kernel/dma/mapping.c | 18 ++++++++++++++++++ 3 files changed, 33 insertions(+) diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h index eaa969be8284..b7b51b89b054 100644 --- a/include/linux/dma-map-ops.h +++ b/include/linux/dma-map-ops.h @@ -11,7 +11,17 @@ struct cma; +/* + * Values for struct dma_map_ops.flags: + * + * DMA_F_PCI_P2PDMA_SUPPORTED: Indicates the dma_map_ops implementation can + * handle PCI P2PDMA pages in the map_sg/unmap_sg operation. + */ +#define DMA_F_PCI_P2PDMA_SUPPORTED (1 << 0) + struct dma_map_ops { + unsigned int flags; + void *(*alloc)(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs); diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 2b0ecf0aa4df..1149540e969f 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -138,6 +138,7 @@ int dma_mmap_attrs(struct device *dev, struct vm_area_struct *vma, unsigned long attrs); bool dma_can_mmap(struct device *dev); int dma_supported(struct device *dev, u64 mask); +bool dma_pci_p2pdma_supported(struct device *dev); int dma_set_mask(struct device *dev, u64 mask); int dma_set_coherent_mask(struct device *dev, u64 mask); u64 dma_get_required_mask(struct device *dev); @@ -242,6 +243,10 @@ static inline int dma_supported(struct device *dev, u64 mask) { return 0; } +static inline bool dma_pci_p2pdma_supported(struct device *dev) +{ + return false; +} static inline int dma_set_mask(struct device *dev, u64 mask) { return -EIO; diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 700a2bb7cc9e..2940977b1030 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -658,6 +658,24 @@ int dma_supported(struct device *dev, u64 mask) } EXPORT_SYMBOL(dma_supported); +bool dma_pci_p2pdma_supported(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + /* if ops is not set, dma direct will be used which supports P2PDMA */ + if (!ops) + return true; + + /* + * Note: dma_ops_bypass is not checked here because P2PDMA should + * not be used with dma mapping ops that do not have support even + * if the specific device is bypassing them. + */ + + return ops->flags & DMA_F_PCI_P2PDMA_SUPPORTED; +} +EXPORT_SYMBOL_GPL(dma_pci_p2pdma_supported); + #ifdef CONFIG_ARCH_HAS_DMA_SET_MASK void arch_dma_set_mask(struct device *dev, u64 mask); #else