From patchwork Tue Oct 25 16:20:04 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksandr Tyshchenko X-Patchwork-Id: 13019515 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 87798C38A2D for ; Tue, 25 Oct 2022 16:20:25 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.429991.681412 (Exim 4.92) (envelope-from ) id 1onMf1-000202-QG; Tue, 25 Oct 2022 16:20:15 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 429991.681412; Tue, 25 Oct 2022 16:20:15 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1onMf1-0001zi-ME; Tue, 25 Oct 2022 16:20:15 +0000 Received: by outflank-mailman (input) for mailman id 429991; Tue, 25 Oct 2022 16:20:14 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1onMf0-0001rM-6V for xen-devel@lists.xenproject.org; Tue, 25 Oct 2022 16:20:14 +0000 Received: from mail-lj1-x235.google.com (mail-lj1-x235.google.com [2a00:1450:4864:20::235]) by se1-gles-flk1.inumbo.com (Halon) with ESMTPS id e7435efd-5480-11ed-8fd0-01056ac49cbb; Tue, 25 Oct 2022 18:20:13 +0200 (CEST) Received: by mail-lj1-x235.google.com with SMTP id bn35so8968089ljb.5 for ; Tue, 25 Oct 2022 09:20:13 -0700 (PDT) Received: from otyshchenko.router ([212.22.223.21]) by smtp.gmail.com with ESMTPSA id a16-20020a2eb550000000b002770302bdffsm540136ljn.105.2022.10.25.09.20.10 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 25 Oct 2022 09:20:11 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: e7435efd-5480-11ed-8fd0-01056ac49cbb DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=CPiIK7IlsJ7E5VINPN3ej70LIynHg49PxYxMULv6O+g=; b=Mcz2WFP8uCN+2nT+Y2LCXeXAkKPmjH58QmfnmrZDOcN5K+WTU1Mcmjc/sFiQ90Bg/t iXNEQCCA+E/XCB83vWVHG0V6MPAib92POhRWkYfk5ka1gkSSEt+bQpjEWq/8lbYkIU47 Qs6eTgoLMfjLQlEgA0MhoYBOoKGLl1E/5LpfAyhxMTJBUIZSjejfGvCjir8IMkmKJ0Kp hMc/y55iOxg9vqAcs2CTMCZNI+Vxr0Pwzx00U42fhwCvw8zAFp4qDdkLj+YdFzQCuhQp mbrxa+MAlZEHS/+kprmjC+KVPUcTjOvZTzB2rAWsHtjgStKg5yumkz3HxKOEOf2ahil3 Yy2Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=CPiIK7IlsJ7E5VINPN3ej70LIynHg49PxYxMULv6O+g=; b=OV/kwUaeNWj+fOf9jTrHyQC8LanWvG0CM+gXb0NU2WZ+cbcssYjXGuLMgpE6/bDJJs pgBoeewYeOnmg1vgn6Vq/lbEIF0yoOQuVHfyYWa29e7eEy6Wl8ybQt3QGICDokOFO8v4 O5qIMnKVFgk0Ej7voJpNzPho+gg7tHCejEgkGPyC15wUyfABbhcUmssL7MAY7RCUYT/g 0FpfsHNvazkCLBgmLKoH6o/pKiL7BYN81+TCJtU2QYHzkEr88VXGW31hxKRxLyLwwP58 eknWsd9mWDL8dmAqpPxmmNZknDKRxRvf5ovv4EaJAK2AA7bK//i7d1o1GpieJV2bpf2n CZDQ== X-Gm-Message-State: ACrzQf1hUvuCBYCekm+HLWuLWmO6sbVyZcgf7/sa6lcg8NbPv2a537e6 21bVxFrluW5Igty7V9oLLEOHFui8KNE= X-Google-Smtp-Source: AMsMyM62fltFfmb8eUA4lFmsFonT3s3D9baIIhB+ZUg06Ktu/2pzGx7vkhjbjBeMjDCfkQWNML2TEg== X-Received: by 2002:a05:651c:33c:b0:277:e2b:de4a with SMTP id b28-20020a05651c033c00b002770e2bde4amr3738346ljp.55.1666714812379; Tue, 25 Oct 2022 09:20:12 -0700 (PDT) From: Oleksandr Tyshchenko To: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org Cc: Oleksandr Tyshchenko , Stefano Stabellini , Juergen Gross , Xenia Ragiadakou Subject: [PATCH V4 2/2] xen/virtio: Handle PCI devices which Host controller is described in DT Date: Tue, 25 Oct 2022 19:20:04 +0300 Message-Id: <20221025162004.8501-3-olekstysh@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221025162004.8501-1-olekstysh@gmail.com> References: <20221025162004.8501-1-olekstysh@gmail.com> MIME-Version: 1.0 From: Oleksandr Tyshchenko Use the same "xen-grant-dma" device concept for the PCI devices behind device-tree based PCI Host controller, but with one modification. Unlike for platform devices, we cannot use generic IOMMU bindings (iommus property), as we need to support more flexible configuration. The problem is that PCI devices under the single PCI Host controller may have the backends running in different Xen domains and thus have different endpoints ID (backend domains ID). Add ability to deal with generic PCI-IOMMU bindings (iommu-map/ iommu-map-mask properties) which allows us to describe relationship between PCI devices and backend domains ID properly. To avoid having to look up for the PCI Host bridge twice and reduce the amount of checks pass an extra struct device_node *np to xen_dt_grant_init_backend_domid(). So with current patch the code expects iommus property for the platform devices and iommu-map/iommu-map-mask properties for PCI devices. The example of generated by the toolstack iommu-map property for two PCI devices 0000:00:01.0 and 0000:00:02.0 whose backends are running in different Xen domains with IDs 1 and 2 respectively: iommu-map = <0x08 0xfde9 0x01 0x08 0x10 0xfde9 0x02 0x08>; Signed-off-by: Oleksandr Tyshchenko Reviewed-by: Xenia Ragiadakou Reviewed-by: Stefano Stabellini --- Slightly RFC. This is needed to support Xen grant mappings for virtio-pci devices on Arm at some point in the future. The Xen toolstack side is not completely ready yet. Here, for PCI devices we use more flexible way to pass backend domid to the guest than for platform devices. Changes V1 -> V2: - update commit description - rebase - rework to use generic PCI-IOMMU bindings instead of generic IOMMU bindings Changes V2 -> V3: - update commit description, add an example - drop xen_dt_map_id() and squash xen_dt_get_pci_host_node() with xen_dt_get_node() - pass struct device_node *np to xen_is_dt_grant_dma_device() and xen_dt_grant_init_backend_domid() - pass domid_t *backend_domid instead of struct xen_grant_dma_data *data to xen_dt_grant_init_backend_domid() Changes V3 -> V4: - just rebase on new prereq patch "xen/virtio: Optimize the setup of "xen-grant-dma" devices" Previous discussion is at: https://lore.kernel.org/xen-devel/20221006174804.2003029-1-olekstysh@gmail.com/ https://lore.kernel.org/xen-devel/20221015153409.918775-1-olekstysh@gmail.com/ https://lore.kernel.org/xen-devel/20221021172408.77397-1-olekstysh@gmail.com/ Based on: https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git/log/?h=for-linus-6.1 --- --- drivers/xen/grant-dma-ops.c | 46 +++++++++++++++++++++++++++++++------ 1 file changed, 39 insertions(+), 7 deletions(-) diff --git a/drivers/xen/grant-dma-ops.c b/drivers/xen/grant-dma-ops.c index 1e797a043980..9784a77fa3c9 100644 --- a/drivers/xen/grant-dma-ops.c +++ b/drivers/xen/grant-dma-ops.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -292,15 +293,43 @@ static const struct dma_map_ops xen_grant_dma_ops = { .dma_supported = xen_grant_dma_supported, }; +static struct device_node *xen_dt_get_node(struct device *dev) +{ + if (dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + struct pci_bus *bus = pdev->bus; + + /* Walk up to the root bus to look for PCI Host controller */ + while (!pci_is_root_bus(bus)) + bus = bus->parent; + + return of_node_get(bus->bridge->parent->of_node); + } + + return of_node_get(dev->of_node); +} + static int xen_dt_grant_init_backend_domid(struct device *dev, + struct device_node *np, domid_t *backend_domid) { - struct of_phandle_args iommu_spec; + struct of_phandle_args iommu_spec = { .args_count = 1 }; - if (of_parse_phandle_with_args(dev->of_node, "iommus", "#iommu-cells", - 0, &iommu_spec)) { - dev_dbg(dev, "Cannot parse iommus property\n"); - return -ESRCH; + if (dev_is_pci(dev)) { + struct pci_dev *pdev = to_pci_dev(dev); + u32 rid = PCI_DEVID(pdev->bus->number, pdev->devfn); + + if (of_map_id(np, rid, "iommu-map", "iommu-map-mask", &iommu_spec.np, + iommu_spec.args)) { + dev_dbg(dev, "Cannot translate ID\n"); + return -ESRCH; + } + } else { + if (of_parse_phandle_with_args(np, "iommus", "#iommu-cells", + 0, &iommu_spec)) { + dev_dbg(dev, "Cannot parse iommus property\n"); + return -ESRCH; + } } if (!of_device_is_compatible(iommu_spec.np, "xen,grant-dma") || @@ -324,10 +353,13 @@ static int xen_dt_grant_init_backend_domid(struct device *dev, static int xen_grant_init_backend_domid(struct device *dev, domid_t *backend_domid) { + struct device_node *np; int ret = -ENODEV; - if (dev->of_node) { - ret = xen_dt_grant_init_backend_domid(dev, backend_domid); + np = xen_dt_get_node(dev); + if (np) { + ret = xen_dt_grant_init_backend_domid(dev, np, backend_domid); + of_node_put(np); } else if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain()) { dev_info(dev, "Using dom0 as backend\n"); *backend_domid = 0;