From mboxrd@z Thu Jan 1 00:00:00 1970 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=-18.0 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,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 DD5CBC43462 for ; Tue, 11 May 2021 16:06:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD86E6187E for ; Tue, 11 May 2021 16:06:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231613AbhEKQHb (ORCPT ); Tue, 11 May 2021 12:07:31 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:35832 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231162AbhEKQH1 (ORCPT ); Tue, 11 May 2021 12:07:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1620749179; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=tMAIqc3ynAUjVNMmJZyA97GO/AXkgEpCMde9bMg3dSI=; b=RsQdAGC4JcZuadUAtxVg3eoYYvp9gOjVAEvD7/yZhxEIO+mdxXtivVxwDiVLYz+FQIUmqj e/CrFI1Yj2qdOd6vPbUUlJBbqxzFWStquW61n/PvJEqWCipBi3UmA7eAAxr54B9a8PfT5B ioe97Vm5Aqn/SvsluJpkQNdgMVsaL9A= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-533-qB9XlPV8NbqOjRN04e3B5A-1; Tue, 11 May 2021 12:06:16 -0400 X-MC-Unique: qB9XlPV8NbqOjRN04e3B5A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 3F7ED8C8640; Tue, 11 May 2021 16:06:12 +0000 (UTC) Received: from [10.3.115.19] (ovpn-115-19.phx2.redhat.com [10.3.115.19]) by smtp.corp.redhat.com (Postfix) with ESMTP id 30ECA6E53E; Tue, 11 May 2021 16:06:08 +0000 (UTC) Subject: Re: [PATCH 07/16] PCI/P2PDMA: Make pci_p2pdma_map_type() non-static To: Logan Gunthorpe , 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 , Matthew Wilcox , Daniel Vetter , Jakowski Andrzej , Minturn Dave B , Jason Ekstrand , Dave Hansen , Xiong Jianxin , Bjorn Helgaas , Ira Weiny , Robin Murphy References: <20210408170123.8788-1-logang@deltatee.com> <20210408170123.8788-8-logang@deltatee.com> From: Don Dutile Message-ID: Date: Tue, 11 May 2021 12:06:07 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20210408170123.8788-8-logang@deltatee.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/8/21 1:01 PM, Logan Gunthorpe wrote: > pci_p2pdma_map_type() will be needed by the dma-iommu map_sg > implementation because it will need to determine the mapping type > ahead of actually doing the mapping to create the actual iommu mapping. > > Signed-off-by: Logan Gunthorpe > --- > drivers/pci/p2pdma.c | 34 +++++++++++++++++++++++----------- > include/linux/pci-p2pdma.h | 15 +++++++++++++++ > 2 files changed, 38 insertions(+), 11 deletions(-) > > diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c > index bcb1a6d6119d..38c93f57a941 100644 > --- a/drivers/pci/p2pdma.c > +++ b/drivers/pci/p2pdma.c > @@ -20,13 +20,6 @@ > #include > #include > > -enum pci_p2pdma_map_type { > - PCI_P2PDMA_MAP_UNKNOWN = 0, > - PCI_P2PDMA_MAP_NOT_SUPPORTED, > - PCI_P2PDMA_MAP_BUS_ADDR, > - PCI_P2PDMA_MAP_THRU_HOST_BRIDGE, > -}; > - > struct pci_p2pdma { > struct gen_pool *pool; > bool p2pmem_published; > @@ -822,13 +815,30 @@ void pci_p2pmem_publish(struct pci_dev *pdev, bool publish) > } > EXPORT_SYMBOL_GPL(pci_p2pmem_publish); > > -static enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap, > - struct device *dev) > +/** > + * pci_p2pdma_map_type - return the type of mapping that should be used for > + * a given device and pgmap > + * @pgmap: the pagemap of a page to determine the mapping type for > + * @dev: device that is mapping the page > + * @dma_attrs: the attributes passed to the dma_map operation -- > + * this is so they can be checked to ensure P2PDMA pages were not > + * introduced into an incorrect interface (like dma_map_sg). * > + * > + * Returns one of: > + * PCI_P2PDMA_MAP_NOT_SUPPORTED - The mapping should not be done > + * PCI_P2PDMA_MAP_BUS_ADDR - The mapping should use the PCI bus address > + * PCI_P2PDMA_MAP_THRU_HOST_BRIDGE - The mapping should be done directly > + */ I'd recommend putting these descriptions in the enum's in pci-p2pdma.h . Also, can you use a better description for THRU_HOST_BRIDGE -- it leaves the reader wondering what 'done directly' means. Thanks. -dd > +enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap, > + struct device *dev, unsigned long dma_attrs) > { > struct pci_dev *provider = to_p2p_pgmap(pgmap)->provider; > enum pci_p2pdma_map_type ret; > struct pci_dev *client; > > + WARN_ONCE(!(dma_attrs & __DMA_ATTR_PCI_P2PDMA), > + "PCI P2PDMA pages were mapped with dma_map_sg!"); > + > if (!provider->p2pdma) > return PCI_P2PDMA_MAP_NOT_SUPPORTED; > > @@ -879,7 +889,8 @@ int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg, > struct pci_p2pdma_pagemap *p2p_pgmap = > to_p2p_pgmap(sg_page(sg)->pgmap); > > - switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev)) { > + switch (pci_p2pdma_map_type(sg_page(sg)->pgmap, dev, > + __DMA_ATTR_PCI_P2PDMA)) { > case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: > return dma_map_sg_attrs(dev, sg, nents, dir, attrs); > case PCI_P2PDMA_MAP_BUS_ADDR: > @@ -904,7 +915,8 @@ void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg, > { > enum pci_p2pdma_map_type map_type; > > - map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev); > + map_type = pci_p2pdma_map_type(sg_page(sg)->pgmap, dev, > + __DMA_ATTR_PCI_P2PDMA); > > if (map_type == PCI_P2PDMA_MAP_THRU_HOST_BRIDGE) > dma_unmap_sg_attrs(dev, sg, nents, dir, attrs); > diff --git a/include/linux/pci-p2pdma.h b/include/linux/pci-p2pdma.h > index 8318a97c9c61..a06072ac3a52 100644 > --- a/include/linux/pci-p2pdma.h > +++ b/include/linux/pci-p2pdma.h > @@ -16,6 +16,13 @@ > struct block_device; > struct scatterlist; > > +enum pci_p2pdma_map_type { > + PCI_P2PDMA_MAP_UNKNOWN = 0, > + PCI_P2PDMA_MAP_NOT_SUPPORTED, > + PCI_P2PDMA_MAP_BUS_ADDR, > + PCI_P2PDMA_MAP_THRU_HOST_BRIDGE, > +}; > + > #ifdef CONFIG_PCI_P2PDMA > int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, > u64 offset); > @@ -30,6 +37,8 @@ struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev, > unsigned int *nents, u32 length); > void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl); > void pci_p2pmem_publish(struct pci_dev *pdev, bool publish); > +enum pci_p2pdma_map_type pci_p2pdma_map_type(struct dev_pagemap *pgmap, > + struct device *dev, unsigned long dma_attrs); > int pci_p2pdma_map_sg_attrs(struct device *dev, struct scatterlist *sg, > int nents, enum dma_data_direction dir, unsigned long attrs); > void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg, > @@ -83,6 +92,12 @@ static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev, > static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish) > { > } > +static inline enum pci_p2pdma_map_type pci_p2pdma_map_type( > + struct dev_pagemap *pgmap, struct device *dev, > + unsigned long dma_attrs) > +{ > + return PCI_P2PDMA_MAP_NOT_SUPPORTED; > +} > static inline int pci_p2pdma_map_sg_attrs(struct device *dev, > struct scatterlist *sg, int nents, enum dma_data_direction dir, > unsigned long attrs)