From patchwork Thu Mar 11 23:31:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Logan Gunthorpe X-Patchwork-Id: 12133307 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,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 1F04AC4360C for ; Thu, 11 Mar 2021 23:49:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F32C364F7C for ; Thu, 11 Mar 2021 23:49:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231328AbhCKXtA (ORCPT ); Thu, 11 Mar 2021 18:49:00 -0500 Received: from ale.deltatee.com ([204.191.154.188]:45208 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229587AbhCKXsp (ORCPT ); Thu, 11 Mar 2021 18:48:45 -0500 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=5m+PzWqUWnOR3YxadyZCg0MfweU6UruMUlqYZWYNYZM=; b=HV/kvTIN+l3Mjh5BJT+0f0JjD8 P6NqH+K5UqG4RHUSkRXS55CWxhlfN8E2lcAnezcnbPCxPgqjSDCeptqojK/JrP65f6TtoiSv+NLzp i6CTfLrDVHkXIL8Jm++pnpKOzRx64R6plr4lmBgo2J86KWpIa5RUob7/lMB/i+2tMsw3mKATtPvU7 k5xJoWpB3bmKp16E0VOC+RoakdJYP+xRQUbJZopKLN8frZh+KI0iyApQnWSi0ByDGcKuFpu1/qnh7 5Pa7/Ot9X9cYqQbjRcHQ+GxkViOGRZhbHsZ8W+7xZ3B0JN6TLomzW1Z4Z5QoUjYegFZVnsHaWnImv uJfSt0Bw==; 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 1lKUmp-0003ev-A4; Thu, 11 Mar 2021 16:32:12 -0700 Received: from gunthorp by cgy1-donard.priv.deltatee.com with local (Exim 4.92) (envelope-from ) id 1lKUmW-00024b-Hp; Thu, 11 Mar 2021 16:31:52 -0700 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?= , Ira Weiny , John Hubbard , Don Dutile , Matthew Wilcox , Daniel Vetter , Jakowski Andrzej , Minturn Dave B , Jason Ekstrand , Dave Hansen , Xiong Jianxin , Logan Gunthorpe Date: Thu, 11 Mar 2021 16:31:36 -0700 Message-Id: <20210311233142.7900-7-logang@deltatee.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20210311233142.7900-1-logang@deltatee.com> References: <20210311233142.7900-1-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, dan.j.williams@intel.com, iweiny@intel.com, andrzej.jakowski@intel.com, dave.b.minturn@intel.com, jianxin.xiong@intel.com, logang@deltatee.com X-SA-Exim-Mail-From: gunthorp@deltatee.com Subject: [RFC PATCH v2 06/11] dma-direct: Support PCI P2PDMA pages in dma-direct map_sg 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 PCI P2PDMA support for dma_direct_map_sg() so that it can map PCI P2PDMA pages directly without a hack in the callers. This allows for heterogeneous SGLs that contain both P2PDMA and regular pages. SGL segments that contain PCI bus addresses are marked with sg_mark_pci_p2pdma() and are ignored when unmapped. Signed-off-by: Logan Gunthorpe --- kernel/dma/direct.c | 35 ++++++++++++++++++++++++++++++++--- kernel/dma/mapping.c | 13 ++++++++++--- 2 files changed, 42 insertions(+), 6 deletions(-) diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 002268262c9a..f326d32062dd 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -13,6 +13,7 @@ #include #include #include +#include #include "direct.h" /* @@ -387,19 +388,47 @@ void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl, struct scatterlist *sg; int i; - for_each_sg(sgl, sg, nents, i) + for_each_sg(sgl, sg, nents, i) { + if (sg_is_pci_p2pdma(sg)) + continue; + dma_direct_unmap_page(dev, sg->dma_address, sg_dma_len(sg), dir, attrs); + } } #endif int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir, unsigned long attrs) { - int i; + struct dev_pagemap *pgmap = NULL; + int i, map = -1, ret = 0; struct scatterlist *sg; + u64 bus_off; for_each_sg(sgl, sg, nents, i) { + if (is_pci_p2pdma_page(sg_page(sg))) { + if (sg_page(sg)->pgmap != pgmap) { + pgmap = sg_page(sg)->pgmap; + map = pci_p2pdma_dma_map_type(dev, pgmap); + bus_off = pci_p2pdma_bus_offset(sg_page(sg)); + } + + if (map < 0) { + sg->dma_address = DMA_MAPPING_ERROR; + ret = -EREMOTEIO; + goto out_unmap; + } + + if (map) { + sg->dma_address = sg_phys(sg) + sg->offset - + bus_off; + sg_dma_len(sg) = sg->length; + sg_mark_pci_p2pdma(sg); + continue; + } + } + sg->dma_address = dma_direct_map_page(dev, sg_page(sg), sg->offset, sg->length, dir, attrs); if (sg->dma_address == DMA_MAPPING_ERROR) @@ -411,7 +440,7 @@ int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, out_unmap: dma_direct_unmap_sg(dev, sgl, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC); - return 0; + return ret; } dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr, diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index b6a633679933..adc1a83950be 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -178,8 +178,15 @@ void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size, EXPORT_SYMBOL(dma_unmap_page_attrs); /* - * dma_maps_sg_attrs returns 0 on error and > 0 on success. - * It should never return a value < 0. + * dma_maps_sg_attrs returns 0 on any resource error and > 0 on success. + * + * If 0 is returned, the mapping can be retried and will succeed once + * sufficient resources are available. + * + * If there are P2PDMA pages in the scatterlist then this function may + * return -EREMOTEIO to indicate that the pages are not mappable by the + * device. In this case, an error should be returned for the IO as it + * will never be successfully retried. */ int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents, enum dma_data_direction dir, unsigned long attrs) @@ -197,7 +204,7 @@ int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg, int nents, ents = dma_direct_map_sg(dev, sg, nents, dir, attrs); else ents = ops->map_sg(dev, sg, nents, dir, attrs); - BUG_ON(ents < 0); + debug_dma_map_sg(dev, sg, nents, ents, dir); return ents;