From patchwork Tue Aug 18 19:04:00 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: wdavis@nvidia.com X-Patchwork-Id: 508437 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 1E80214032E for ; Wed, 19 Aug 2015 05:19:17 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753491AbbHRTTN (ORCPT ); Tue, 18 Aug 2015 15:19:13 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:3515 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752940AbbHRTTM (ORCPT ); Tue, 18 Aug 2015 15:19:12 -0400 Received: from hqnvupgp07.nvidia.com (Not Verified[216.228.121.13]) by hqemgate14.nvidia.com id ; Tue, 18 Aug 2015 12:18:27 -0700 Received: from hqemhub02.nvidia.com ([172.20.12.94]) by hqnvupgp07.nvidia.com (PGP Universal service); Tue, 18 Aug 2015 12:15:57 -0700 X-PGP-Universal: processed; by hqnvupgp07.nvidia.com on Tue, 18 Aug 2015 12:15:57 -0700 Received: from HQPUB102.nvidia.com (172.18.146.14) by hqemhub02.nvidia.com (172.20.150.31) with Microsoft SMTP Server (TLS) id 8.3.342.0; Tue, 18 Aug 2015 12:19:11 -0700 Received: from HQMAIL103.nvidia.com (172.20.187.11) by HQPUB102.nvidia.com (172.18.146.14) with Microsoft SMTP Server (TLS) id 15.0.1044.25; Tue, 18 Aug 2015 19:19:11 +0000 Received: from hqnvemgw02.nvidia.com (172.16.227.111) by HQMAIL103.nvidia.com (172.20.187.11) with Microsoft SMTP Server id 15.0.1044.25 via Frontend Transport; Tue, 18 Aug 2015 19:19:11 +0000 Received: from wdavis-lt.nvidia.com (Not Verified[10.20.168.59]) by hqnvemgw02.nvidia.com with MailMarshal (v7,1,2,5326) id ; Tue, 18 Aug 2015 12:19:10 -0700 From: Will Davis To: Bjorn Helgaas CC: Alex Williamson , Joerg Roedel , , , Konrad Wilk , Mark Hounschell , "David S. Miller" , Jonathan Corbet , Terence Ripperda , John Hubbard , Jerome Glisse , Will Davis Subject: [PATCH v5 04/13] DMA-API: Introduce dma_(un)map_peer_resource Date: Tue, 18 Aug 2015 14:04:00 -0500 Message-ID: <1439924649-29698-5-git-send-email-wdavis@nvidia.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1439924649-29698-1-git-send-email-wdavis@nvidia.com> References: <1439924649-29698-1-git-send-email-wdavis@nvidia.com> X-NVConfidentiality: public MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Add functions to DMA-map and -unmap a peer device's resource for a given device. This will allow devices to DMA-map, for example, another device's BAR region on PCI to enable peer-to-peer transactions. Guard these new functions behind CONFIG_HAS_DMA_P2P. Signed-off-by: Will Davis --- include/asm-generic/dma-mapping-common.h | 43 ++++++++++++++++++++++++++++++++ include/linux/dma-mapping.h | 12 +++++++++ 2 files changed, 55 insertions(+) diff --git a/include/asm-generic/dma-mapping-common.h b/include/asm-generic/dma-mapping-common.h index 940d5ec..45eec17 100644 --- a/include/asm-generic/dma-mapping-common.h +++ b/include/asm-generic/dma-mapping-common.h @@ -73,6 +73,42 @@ static inline void dma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg ops->unmap_sg(dev, sg, nents, dir, attrs); } +#ifdef CONFIG_HAS_DMA_P2P +static inline dma_peer_addr_t dma_map_peer_resource_attrs(struct device *dev, + struct device *peer, + struct resource *res, + size_t offset, + size_t size, + enum dma_data_direction dir, + struct dma_attrs *attrs) +{ + struct dma_map_ops *ops = get_dma_ops(dev); + dma_peer_addr_t addr; + + BUG_ON(!valid_dma_direction(dir)); + BUG_ON(ops->map_peer_resource == NULL); + addr = ops->map_peer_resource(dev, peer, res, offset, size, dir, + attrs); + debug_dma_map_peer_resource(dev, peer, res, offset, size, dir, addr); + + return addr; +} + +static inline void dma_unmap_peer_resource_attrs(struct device *dev, + dma_peer_addr_t addr, + size_t size, + enum dma_data_direction dir, + struct dma_attrs *attrs) +{ + struct dma_map_ops *ops = get_dma_ops(dev); + + BUG_ON(!valid_dma_direction(dir)); + if (ops->unmap_peer_resource) + ops->unmap_peer_resource(dev, addr, size, dir, attrs); + debug_dma_unmap_peer_resource(dev, addr, size, dir); +} +#endif + static inline dma_addr_t dma_map_page(struct device *dev, struct page *page, size_t offset, size_t size, enum dma_data_direction dir) @@ -181,6 +217,13 @@ dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, NULL) #define dma_unmap_sg(d, s, n, r) dma_unmap_sg_attrs(d, s, n, r, NULL) +#ifdef CONFIG_HAS_DMA_P2P +#define dma_map_peer_resource(d, p, e, o, s, r) \ + dma_map_peer_resource_attrs(d, p, e, o, s, r, NULL) +#define dma_unmap_peer_resource(d, a, s, r) \ + dma_unmap_peer_resource_attrs(d, a, s, r, NULL) +#endif + extern int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, dma_addr_t dma_addr, size_t size); diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index ac07ff0..7b8fddc 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -34,6 +34,18 @@ struct dma_map_ops { void (*unmap_page)(struct device *dev, dma_addr_t dma_handle, size_t size, enum dma_data_direction dir, struct dma_attrs *attrs); +#ifdef CONFIG_HAS_DMA_P2P + dma_peer_addr_t (*map_peer_resource)(struct device *dev, + struct device *peer, + struct resource *res, + unsigned long offset, size_t size, + enum dma_data_direction dir, + struct dma_attrs *attrs); + void (*unmap_peer_resource)(struct device *dev, + dma_peer_addr_t dma_handle, + size_t size, enum dma_data_direction dir, + struct dma_attrs *attrs); +#endif /* * map_sg returns 0 on error and a value > 0 on success. * It should never return a value < 0.