From patchwork Fri Oct 12 14:59:11 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983120 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcf6MnCz9s3T for ; Sat, 13 Oct 2018 02:00:50 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728850AbeJLWdk (ORCPT ); Fri, 12 Oct 2018 18:33:40 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52676 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728182AbeJLWdj (ORCPT ); Fri, 12 Oct 2018 18:33:39 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A785A1596; Fri, 12 Oct 2018 08:00:48 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B7C5F3F5BC; Fri, 12 Oct 2018 08:00:45 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 1/7] dt-bindings: virtio-mmio: Add IOMMU description Date: Fri, 12 Oct 2018 15:59:11 +0100 Message-Id: <20181012145917.6840-2-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The nature of a virtio-mmio node is discovered by the virtio driver at probe time. However the DMA relation between devices must be described statically. When a virtio-mmio node is a virtio-iommu device, it needs an "#iommu-cells" property as specified by bindings/iommu/iommu.txt. Otherwise, the virtio-mmio device may perform DMA through an IOMMU, which requires an "iommus" property. Describe these requirements in the device-tree bindings documentation. Signed-off-by: Jean-Philippe Brucker Reviewed-by: Rob Herring Reviewed-by: Eric Auger --- .../devicetree/bindings/virtio/mmio.txt | 30 +++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/Documentation/devicetree/bindings/virtio/mmio.txt b/Documentation/devicetree/bindings/virtio/mmio.txt index 5069c1b8e193..748595473b36 100644 --- a/Documentation/devicetree/bindings/virtio/mmio.txt +++ b/Documentation/devicetree/bindings/virtio/mmio.txt @@ -8,10 +8,40 @@ Required properties: - reg: control registers base address and size including configuration space - interrupts: interrupt generated by the device +Required properties for virtio-iommu: + +- #iommu-cells: When the node corresponds to a virtio-iommu device, it is + linked to DMA masters using the "iommus" or "iommu-map" + properties [1][2]. #iommu-cells specifies the size of the + "iommus" property. For virtio-iommu #iommu-cells must be + 1, each cell describing a single endpoint ID. + +Optional properties: + +- iommus: If the device accesses memory through an IOMMU, it should + have an "iommus" property [1]. Since virtio-iommu itself + does not access memory through an IOMMU, the "virtio,mmio" + node cannot have both an "#iommu-cells" and an "iommus" + property. + Example: virtio_block@3000 { compatible = "virtio,mmio"; reg = <0x3000 0x100>; interrupts = <41>; + + /* Device has endpoint ID 23 */ + iommus = <&viommu 23> } + + viommu: virtio_iommu@3100 { + compatible = "virtio,mmio"; + reg = <0x3100 0x100>; + interrupts = <42>; + + #iommu-cells = <1> + } + +[1] Documentation/devicetree/bindings/iommu/iommu.txt +[2] Documentation/devicetree/bindings/pci/pci-iommu.txt From patchwork Fri Oct 12 14:59:12 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983122 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcj6nxRz9s4Z for ; Sat, 13 Oct 2018 02:00:53 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728786AbeJLWdn (ORCPT ); Fri, 12 Oct 2018 18:33:43 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52692 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728182AbeJLWdn (ORCPT ); Fri, 12 Oct 2018 18:33:43 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D573BF; Fri, 12 Oct 2018 08:00:51 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E4DEE3F5BC; Fri, 12 Oct 2018 08:00:48 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 2/7] dt-bindings: virtio: Add virtio-pci-iommu node Date: Fri, 12 Oct 2018 15:59:12 +0100 Message-Id: <20181012145917.6840-3-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Some systems implement virtio-iommu as a PCI endpoint. The operating systems needs to discover the relationship between IOMMU and masters long before the PCI endpoint gets probed. Add a PCI child node to describe the virtio-iommu device. The virtio-pci-iommu is conceptually split between a PCI programming interface and a translation component on the parent bus. The latter doesn't have a node in the device tree. The virtio-pci-iommu node describes both, by linking the PCI endpoint to "iommus" property of DMA master nodes and to "iommu-map" properties of bus nodes. Signed-off-by: Jean-Philippe Brucker Reviewed-by: Rob Herring Reviewed-by: Eric Auger --- .../devicetree/bindings/virtio/iommu.txt | 66 +++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 Documentation/devicetree/bindings/virtio/iommu.txt diff --git a/Documentation/devicetree/bindings/virtio/iommu.txt b/Documentation/devicetree/bindings/virtio/iommu.txt new file mode 100644 index 000000000000..2407fea0651c --- /dev/null +++ b/Documentation/devicetree/bindings/virtio/iommu.txt @@ -0,0 +1,66 @@ +* virtio IOMMU PCI device + +When virtio-iommu uses the PCI transport, its programming interface is +discovered dynamically by the PCI probing infrastructure. However the +device tree statically describes the relation between IOMMU and DMA +masters. Therefore, the PCI root complex that hosts the virtio-iommu +contains a child node representing the IOMMU device explicitly. + +Required properties: + +- compatible: Should be "virtio,pci-iommu" +- reg: PCI address of the IOMMU. As defined in the PCI Bus + Binding reference [1], the reg property is a five-cell + address encoded as (phys.hi phys.mid phys.lo size.hi + size.lo). phys.hi should contain the device's BDF as + 0b00000000 bbbbbbbb dddddfff 00000000. The other cells + should be zero. +- #iommu-cells: Each platform DMA master managed by the IOMMU is assigned + an endpoint ID, described by the "iommus" property [2]. + For virtio-iommu, #iommu-cells must be 1. + +Notes: + +- DMA from the IOMMU device isn't managed by another IOMMU. Therefore the + virtio-iommu node doesn't have an "iommus" property, and is omitted from + the iommu-map property of the root complex. + +Example: + +pcie@10000000 { + compatible = "pci-host-ecam-generic"; + ... + + /* The IOMMU programming interface uses slot 00:01.0 */ + iommu0: iommu@0008 { + compatible = "virtio,pci-iommu"; + reg = <0x00000800 0 0 0 0>; + #iommu-cells = <1>; + }; + + /* + * The IOMMU manages all functions in this PCI domain except + * itself. Omit BDF 00:01.0. + */ + iommu-map = <0x0 &iommu0 0x0 0x8> + <0x9 &iommu0 0x9 0xfff7>; +}; + +pcie@20000000 { + compatible = "pci-host-ecam-generic"; + ... + /* + * The IOMMU also manages all functions from this domain, + * with endpoint IDs 0x10000 - 0x1ffff + */ + iommu-map = <0x0 &iommu0 0x10000 0x10000>; +}; + +ethernet@fe001000 { + ... + /* The IOMMU manages this platform device with endpoint ID 0x20000 */ + iommus = <&iommu0 0x20000>; +}; + +[1] Documentation/devicetree/bindings/pci/pci.txt +[2] Documentation/devicetree/bindings/iommu/iommu.txt From patchwork Fri Oct 12 14:59:13 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983123 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcm6P7gz9s4Z for ; Sat, 13 Oct 2018 02:00:56 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728860AbeJLWdq (ORCPT ); Fri, 12 Oct 2018 18:33:46 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52722 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728182AbeJLWdq (ORCPT ); Fri, 12 Oct 2018 18:33:46 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0E36715BF; Fri, 12 Oct 2018 08:00:55 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 1E80B3F5BC; Fri, 12 Oct 2018 08:00:51 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 3/7] PCI: OF: Allow endpoints to bypass the iommu Date: Fri, 12 Oct 2018 15:59:13 +0100 Message-Id: <20181012145917.6840-4-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Using the iommu-map binding, endpoints in a given PCI domain can be managed by different IOMMUs. Some virtual machines may allow a subset of endpoints to bypass the IOMMU. In some case the IOMMU itself is presented as a PCI endpoint (e.g. AMD IOMMU and virtio-iommu). Currently, when a PCI root complex has an iommu-map property, the driver requires all endpoints to be described by the property. Allow the iommu-map property to have gaps. Relaxing of_pci_map_rid also allows the msi-map property to have gaps, which is invalid since MSIs always reach an MSI controller. Thankfully Linux will error out later, when attempting to find an MSI domain for the device. Signed-off-by: Jean-Philippe Brucker --- drivers/pci/of.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/drivers/pci/of.c b/drivers/pci/of.c index 1836b8ddf292..2f5015bdb256 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -451,9 +451,10 @@ int of_pci_map_rid(struct device_node *np, u32 rid, return 0; } - pr_err("%pOF: Invalid %s translation - no match for rid 0x%x on %pOF\n", - np, map_name, rid, target && *target ? *target : NULL); - return -EFAULT; + /* Bypasses translation */ + if (id_out) + *id_out = rid; + return 0; } #if IS_ENABLED(CONFIG_OF_IRQ) From patchwork Fri Oct 12 14:59:14 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983124 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcr1Fmqz9s4Z for ; Sat, 13 Oct 2018 02:01:00 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728884AbeJLWdt (ORCPT ); Fri, 12 Oct 2018 18:33:49 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52750 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728182AbeJLWdt (ORCPT ); Fri, 12 Oct 2018 18:33:49 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 3B7EB1684; Fri, 12 Oct 2018 08:00:58 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4B9B13F5BC; Fri, 12 Oct 2018 08:00:55 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 4/7] PCI: OF: Initialize dev->fwnode appropriately Date: Fri, 12 Oct 2018 15:59:14 +0100 Message-Id: <20181012145917.6840-5-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org For PCI devices that have an OF node, set the fwnode as well. This way drivers that rely on fwnode don't need the special case described by commit f94277af03ea ("of/platform: Initialise dev->fwnode appropriately"). Signed-off-by: Jean-Philippe Brucker Acked-by: Bjorn Helgaas --- drivers/pci/of.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/pci/of.c b/drivers/pci/of.c index 2f5015bdb256..8026417fab38 100644 --- a/drivers/pci/of.c +++ b/drivers/pci/of.c @@ -21,12 +21,15 @@ void pci_set_of_node(struct pci_dev *dev) return; dev->dev.of_node = of_pci_find_child_device(dev->bus->dev.of_node, dev->devfn); + if (dev->dev.of_node) + dev->dev.fwnode = &dev->dev.of_node->fwnode; } void pci_release_of_node(struct pci_dev *dev) { of_node_put(dev->dev.of_node); dev->dev.of_node = NULL; + dev->dev.fwnode = NULL; } void pci_set_bus_of_node(struct pci_bus *bus) @@ -35,12 +38,16 @@ void pci_set_bus_of_node(struct pci_bus *bus) bus->dev.of_node = pcibios_get_phb_of_node(bus); else bus->dev.of_node = of_node_get(bus->self->dev.of_node); + + if (bus->dev.of_node) + bus->dev.fwnode = &bus->dev.of_node->fwnode; } void pci_release_bus_of_node(struct pci_bus *bus) { of_node_put(bus->dev.of_node); bus->dev.of_node = NULL; + bus->dev.fwnode = NULL; } struct device_node * __weak pcibios_get_phb_of_node(struct pci_bus *bus) From patchwork Fri Oct 12 14:59:15 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983125 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcw5qnkz9s55 for ; Sat, 13 Oct 2018 02:01:04 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728182AbeJLWdx (ORCPT ); Fri, 12 Oct 2018 18:33:53 -0400 Received: from foss.arm.com ([217.140.101.70]:52772 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728896AbeJLWdx (ORCPT ); Fri, 12 Oct 2018 18:33:53 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id BB06FF; Fri, 12 Oct 2018 08:01:01 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 79D653F5BC; Fri, 12 Oct 2018 08:00:58 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 5/7] iommu: Add virtio-iommu driver Date: Fri, 12 Oct 2018 15:59:15 +0100 Message-Id: <20181012145917.6840-6-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The virtio IOMMU is a para-virtualized device, allowing to send IOMMU requests such as map/unmap over virtio transport without emulating page tables. This implementation handles ATTACH, DETACH, MAP and UNMAP requests. The bulk of the code transforms calls coming from the IOMMU API into corresponding virtio requests. Mappings are kept in an interval tree instead of page tables. Signed-off-by: Jean-Philippe Brucker --- MAINTAINERS | 7 + drivers/iommu/Kconfig | 11 + drivers/iommu/Makefile | 1 + drivers/iommu/virtio-iommu.c | 938 ++++++++++++++++++++++++++++++ include/uapi/linux/virtio_ids.h | 1 + include/uapi/linux/virtio_iommu.h | 101 ++++ 6 files changed, 1059 insertions(+) create mode 100644 drivers/iommu/virtio-iommu.c create mode 100644 include/uapi/linux/virtio_iommu.h diff --git a/MAINTAINERS b/MAINTAINERS index 48a65c3a4189..f02fa65f47e2 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -15599,6 +15599,13 @@ S: Maintained F: drivers/virtio/virtio_input.c F: include/uapi/linux/virtio_input.h +VIRTIO IOMMU DRIVER +M: Jean-Philippe Brucker +L: virtualization@lists.linux-foundation.org +S: Maintained +F: drivers/iommu/virtio-iommu.c +F: include/uapi/linux/virtio_iommu.h + VIRTUAL BOX GUEST DEVICE DRIVER M: Hans de Goede M: Arnd Bergmann diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index c60395b7470f..2dc016dc2b92 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -414,4 +414,15 @@ config QCOM_IOMMU help Support for IOMMU on certain Qualcomm SoCs. +config VIRTIO_IOMMU + bool "Virtio IOMMU driver" + depends on VIRTIO=y + select IOMMU_API + select INTERVAL_TREE + select ARM_DMA_USE_IOMMU if ARM + help + Para-virtualised IOMMU driver with virtio. + + Say Y here if you intend to run this kernel as a guest. + endif # IOMMU_SUPPORT diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile index ab5eba6edf82..4cd643408e49 100644 --- a/drivers/iommu/Makefile +++ b/drivers/iommu/Makefile @@ -31,3 +31,4 @@ obj-$(CONFIG_EXYNOS_IOMMU) += exynos-iommu.o obj-$(CONFIG_FSL_PAMU) += fsl_pamu.o fsl_pamu_domain.o obj-$(CONFIG_S390_IOMMU) += s390-iommu.o obj-$(CONFIG_QCOM_IOMMU) += qcom_iommu.o +obj-$(CONFIG_VIRTIO_IOMMU) += virtio-iommu.o diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c new file mode 100644 index 000000000000..9fb38cd3b727 --- /dev/null +++ b/drivers/iommu/virtio-iommu.c @@ -0,0 +1,938 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Virtio driver for the paravirtualized IOMMU + * + * Copyright (C) 2018 Arm Limited + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +#define MSI_IOVA_BASE 0x8000000 +#define MSI_IOVA_LENGTH 0x100000 + +#define VIOMMU_REQUEST_VQ 0 +#define VIOMMU_NR_VQS 1 + +/* + * During development, it is convenient to time out rather than wait + * indefinitely in atomic context when a device misbehaves and a request doesn't + * return. In production however, some requests shouldn't return until they are + * successful. + */ +#ifdef DEBUG +#define VIOMMU_REQUEST_TIMEOUT 10000 /* 10s */ +#endif + +struct viommu_dev { + struct iommu_device iommu; + struct device *dev; + struct virtio_device *vdev; + + struct ida domain_ids; + + struct virtqueue *vqs[VIOMMU_NR_VQS]; + spinlock_t request_lock; + struct list_head requests; + + /* Device configuration */ + struct iommu_domain_geometry geometry; + u64 pgsize_bitmap; + u8 domain_bits; +}; + +struct viommu_mapping { + phys_addr_t paddr; + struct interval_tree_node iova; + u32 flags; +}; + +struct viommu_domain { + struct iommu_domain domain; + struct viommu_dev *viommu; + struct mutex mutex; + unsigned int id; + + spinlock_t mappings_lock; + struct rb_root_cached mappings; + + unsigned long nr_endpoints; +}; + +struct viommu_endpoint { + struct viommu_dev *viommu; + struct viommu_domain *vdomain; +}; + +struct viommu_request { + struct list_head list; + void *writeback; + unsigned int write_offset; + unsigned int len; + char buf[]; +}; + +#define to_viommu_domain(domain) \ + container_of(domain, struct viommu_domain, domain) + +static int viommu_get_req_errno(void *buf, size_t len) +{ + struct virtio_iommu_req_tail *tail = buf + len - sizeof(*tail); + + switch (tail->status) { + case VIRTIO_IOMMU_S_OK: + return 0; + case VIRTIO_IOMMU_S_UNSUPP: + return -ENOSYS; + case VIRTIO_IOMMU_S_INVAL: + return -EINVAL; + case VIRTIO_IOMMU_S_RANGE: + return -ERANGE; + case VIRTIO_IOMMU_S_NOENT: + return -ENOENT; + case VIRTIO_IOMMU_S_FAULT: + return -EFAULT; + case VIRTIO_IOMMU_S_IOERR: + case VIRTIO_IOMMU_S_DEVERR: + default: + return -EIO; + } +} + +static void viommu_set_req_status(void *buf, size_t len, int status) +{ + struct virtio_iommu_req_tail *tail = buf + len - sizeof(*tail); + + tail->status = status; +} + +static off_t viommu_get_req_offset(struct viommu_dev *viommu, + struct virtio_iommu_req_head *req, + size_t len) +{ + size_t tail_size = sizeof(struct virtio_iommu_req_tail); + + return len - tail_size; +} + +/* + * __viommu_sync_req - Complete all in-flight requests + * + * Wait for all added requests to complete. When this function returns, all + * requests that were in-flight at the time of the call have completed. + */ +static int __viommu_sync_req(struct viommu_dev *viommu) +{ + int ret = 0; + unsigned int len; + size_t write_len; + ktime_t timeout = 0; + struct viommu_request *req; + struct virtqueue *vq = viommu->vqs[VIOMMU_REQUEST_VQ]; + + assert_spin_locked(&viommu->request_lock); +#ifdef DEBUG + timeout = ktime_add_ms(ktime_get(), VIOMMU_REQUEST_TIMEOUT); +#endif + virtqueue_kick(vq); + + while (!list_empty(&viommu->requests)) { + len = 0; + req = virtqueue_get_buf(vq, &len); + if (req == NULL) { + if (!timeout || ktime_before(ktime_get(), timeout)) + continue; + + /* After timeout, remove all requests */ + req = list_first_entry(&viommu->requests, + struct viommu_request, list); + ret = -ETIMEDOUT; + } + + if (!len) + viommu_set_req_status(req->buf, req->len, + VIRTIO_IOMMU_S_IOERR); + + write_len = req->len - req->write_offset; + if (req->writeback && len >= write_len) + memcpy(req->writeback, req->buf + req->write_offset, + write_len); + + list_del(&req->list); + kfree(req); + } + + return ret; +} + +static int viommu_sync_req(struct viommu_dev *viommu) +{ + int ret; + unsigned long flags; + + spin_lock_irqsave(&viommu->request_lock, flags); + ret = __viommu_sync_req(viommu); + if (ret) + dev_dbg(viommu->dev, "could not sync requests (%d)\n", ret); + spin_unlock_irqrestore(&viommu->request_lock, flags); + + return ret; +} + +/* + * __viommu_add_request - Add one request to the queue + * @buf: pointer to the request buffer + * @len: length of the request buffer + * @writeback: copy data back to the buffer when the request completes. + * + * Add a request to the queue. Only synchronize the queue if it's already full. + * Otherwise don't kick the queue nor wait for requests to complete. + * + * When @writeback is true, data written by the device, including the request + * status, is copied into @buf after the request completes. This is unsafe if + * the caller allocates @buf on stack and drops the lock between add_req() and + * sync_req(). + * + * Return 0 if the request was successfully added to the queue. + */ +static int __viommu_add_req(struct viommu_dev *viommu, void *buf, size_t len, + bool writeback) +{ + int ret; + off_t write_offset; + struct viommu_request *req; + struct scatterlist top_sg, bottom_sg; + struct scatterlist *sg[2] = { &top_sg, &bottom_sg }; + struct virtqueue *vq = viommu->vqs[VIOMMU_REQUEST_VQ]; + + assert_spin_locked(&viommu->request_lock); + + write_offset = viommu_get_req_offset(viommu, buf, len); + if (!write_offset) + return -EINVAL; + + req = kzalloc(sizeof(*req) + len, GFP_ATOMIC); + if (!req) + return -ENOMEM; + + req->len = len; + if (writeback) { + req->writeback = buf + write_offset; + req->write_offset = write_offset; + } + memcpy(&req->buf, buf, write_offset); + + sg_init_one(&top_sg, req->buf, write_offset); + sg_init_one(&bottom_sg, req->buf + write_offset, len - write_offset); + + ret = virtqueue_add_sgs(vq, sg, 1, 1, req, GFP_ATOMIC); + if (ret == -ENOSPC) { + /* If the queue is full, sync and retry */ + if (!__viommu_sync_req(viommu)) + ret = virtqueue_add_sgs(vq, sg, 1, 1, req, GFP_ATOMIC); + } + if (ret) + goto err_free; + + list_add_tail(&req->list, &viommu->requests); + return 0; + +err_free: + kfree(req); + return ret; +} + +static int viommu_add_req(struct viommu_dev *viommu, void *buf, size_t len) +{ + int ret; + unsigned long flags; + + spin_lock_irqsave(&viommu->request_lock, flags); + ret = __viommu_add_req(viommu, buf, len, false); + if (ret) + dev_dbg(viommu->dev, "could not add request: %d\n", ret); + spin_unlock_irqrestore(&viommu->request_lock, flags); + + return ret; +} + +/* + * Send a request and wait for it to complete. Return the request status (as an + * errno) + */ +static int viommu_send_req_sync(struct viommu_dev *viommu, void *buf, + size_t len) +{ + int ret; + unsigned long flags; + + spin_lock_irqsave(&viommu->request_lock, flags); + + ret = __viommu_add_req(viommu, buf, len, true); + if (ret) { + dev_dbg(viommu->dev, "could not add request (%d)\n", ret); + goto out_unlock; + } + + ret = __viommu_sync_req(viommu); + if (ret) { + dev_dbg(viommu->dev, "could not sync requests (%d)\n", ret); + /* Fall-through (get the actual request status) */ + } + + ret = viommu_get_req_errno(buf, len); +out_unlock: + spin_unlock_irqrestore(&viommu->request_lock, flags); + return ret; +} + +/* + * viommu_add_mapping - add a mapping to the internal tree + * + * On success, return the new mapping. Otherwise return NULL. + */ +static struct viommu_mapping * +viommu_add_mapping(struct viommu_domain *vdomain, unsigned long iova, + phys_addr_t paddr, size_t size, u32 flags) +{ + unsigned long irqflags; + struct viommu_mapping *mapping; + + mapping = kzalloc(sizeof(*mapping), GFP_ATOMIC); + if (!mapping) + return NULL; + + mapping->paddr = paddr; + mapping->iova.start = iova; + mapping->iova.last = iova + size - 1; + mapping->flags = flags; + + spin_lock_irqsave(&vdomain->mappings_lock, irqflags); + interval_tree_insert(&mapping->iova, &vdomain->mappings); + spin_unlock_irqrestore(&vdomain->mappings_lock, irqflags); + + return mapping; +} + +/* + * viommu_del_mappings - remove mappings from the internal tree + * + * @vdomain: the domain + * @iova: start of the range + * @size: size of the range. A size of 0 corresponds to the entire address + * space. + * + * On success, returns the number of unmapped bytes (>= size) + */ +static size_t viommu_del_mappings(struct viommu_domain *vdomain, + unsigned long iova, size_t size) +{ + size_t unmapped = 0; + unsigned long flags; + unsigned long last = iova + size - 1; + struct viommu_mapping *mapping = NULL; + struct interval_tree_node *node, *next; + + spin_lock_irqsave(&vdomain->mappings_lock, flags); + next = interval_tree_iter_first(&vdomain->mappings, iova, last); + while (next) { + node = next; + mapping = container_of(node, struct viommu_mapping, iova); + next = interval_tree_iter_next(node, iova, last); + + /* Trying to split a mapping? */ + if (mapping->iova.start < iova) + break; + + /* + * Note that for a partial range, this will return the full + * mapping so we avoid sending split requests to the device. + */ + unmapped += mapping->iova.last - mapping->iova.start + 1; + + interval_tree_remove(node, &vdomain->mappings); + kfree(mapping); + } + spin_unlock_irqrestore(&vdomain->mappings_lock, flags); + + return unmapped; +} + +/* + * viommu_replay_mappings - re-send MAP requests + * + * When reattaching a domain that was previously detached from all endpoints, + * mappings were deleted from the device. Re-create the mappings available in + * the internal tree. + */ +static int viommu_replay_mappings(struct viommu_domain *vdomain) +{ + int ret; + unsigned long flags; + struct viommu_mapping *mapping; + struct interval_tree_node *node; + struct virtio_iommu_req_map map; + + spin_lock_irqsave(&vdomain->mappings_lock, flags); + node = interval_tree_iter_first(&vdomain->mappings, 0, -1UL); + while (node) { + mapping = container_of(node, struct viommu_mapping, iova); + map = (struct virtio_iommu_req_map) { + .head.type = VIRTIO_IOMMU_T_MAP, + .domain = cpu_to_le32(vdomain->id), + .virt_start = cpu_to_le64(mapping->iova.start), + .virt_end = cpu_to_le64(mapping->iova.last), + .phys_start = cpu_to_le64(mapping->paddr), + .flags = cpu_to_le32(mapping->flags), + }; + + ret = viommu_send_req_sync(vdomain->viommu, &map, sizeof(map)); + if (ret) + break; + + node = interval_tree_iter_next(node, 0, -1UL); + } + spin_unlock_irqrestore(&vdomain->mappings_lock, flags); + + return ret; +} + +/* IOMMU API */ + +static struct iommu_domain *viommu_domain_alloc(unsigned type) +{ + struct viommu_domain *vdomain; + + if (type != IOMMU_DOMAIN_UNMANAGED && type != IOMMU_DOMAIN_DMA) + return NULL; + + vdomain = kzalloc(sizeof(*vdomain), GFP_KERNEL); + if (!vdomain) + return NULL; + + mutex_init(&vdomain->mutex); + spin_lock_init(&vdomain->mappings_lock); + vdomain->mappings = RB_ROOT_CACHED; + + if (type == IOMMU_DOMAIN_DMA && + iommu_get_dma_cookie(&vdomain->domain)) { + kfree(vdomain); + return NULL; + } + + return &vdomain->domain; +} + +static int viommu_domain_finalise(struct viommu_dev *viommu, + struct iommu_domain *domain) +{ + int ret; + struct viommu_domain *vdomain = to_viommu_domain(domain); + unsigned int max_domain = viommu->domain_bits > 31 ? ~0 : + (1U << viommu->domain_bits) - 1; + + vdomain->viommu = viommu; + + domain->pgsize_bitmap = viommu->pgsize_bitmap; + domain->geometry = viommu->geometry; + + ret = ida_alloc_max(&viommu->domain_ids, max_domain, GFP_KERNEL); + if (ret >= 0) + vdomain->id = (unsigned int)ret; + + return ret > 0 ? 0 : ret; +} + +static void viommu_domain_free(struct iommu_domain *domain) +{ + struct viommu_domain *vdomain = to_viommu_domain(domain); + + iommu_put_dma_cookie(domain); + + /* Free all remaining mappings (size 2^64) */ + viommu_del_mappings(vdomain, 0, 0); + + if (vdomain->viommu) + ida_free(&vdomain->viommu->domain_ids, vdomain->id); + + kfree(vdomain); +} + +static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev) +{ + int i; + int ret = 0; + struct virtio_iommu_req_attach req; + struct iommu_fwspec *fwspec = dev->iommu_fwspec; + struct viommu_endpoint *vdev = fwspec->iommu_priv; + struct viommu_domain *vdomain = to_viommu_domain(domain); + + mutex_lock(&vdomain->mutex); + if (!vdomain->viommu) { + /* + * Initialize the domain proper now that we know which viommu + * owns it. + */ + ret = viommu_domain_finalise(vdev->viommu, domain); + } else if (vdomain->viommu != vdev->viommu) { + dev_err(dev, "cannot attach to foreign vIOMMU\n"); + ret = -EXDEV; + } + mutex_unlock(&vdomain->mutex); + + if (ret) + return ret; + + /* + * In the virtio-iommu device, when attaching the endpoint to a new + * domain, it is detached from the old one and, if as as a result the + * old domain isn't attached to any endpoint, all mappings are removed + * from the old domain and it is freed. + * + * In the driver the old domain still exists, and its mappings will be + * recreated if it gets reattached to an endpoint. Otherwise it will be + * freed explicitly. + * + * vdev->vdomain is protected by group->mutex + */ + if (vdev->vdomain) + vdev->vdomain->nr_endpoints--; + + req = (struct virtio_iommu_req_attach) { + .head.type = VIRTIO_IOMMU_T_ATTACH, + .domain = cpu_to_le32(vdomain->id), + }; + + for (i = 0; i < fwspec->num_ids; i++) { + req.endpoint = cpu_to_le32(fwspec->ids[i]); + + ret = viommu_send_req_sync(vdomain->viommu, &req, sizeof(req)); + if (ret) + return ret; + } + + if (!vdomain->nr_endpoints) { + /* + * This endpoint is the first to be attached to the domain. + * Replay existing mappings (e.g. SW MSI). + */ + ret = viommu_replay_mappings(vdomain); + if (ret) + return ret; + } + + vdomain->nr_endpoints++; + vdev->vdomain = vdomain; + + return 0; +} + +static int viommu_map(struct iommu_domain *domain, unsigned long iova, + phys_addr_t paddr, size_t size, int prot) +{ + int ret; + int flags; + struct viommu_mapping *mapping; + struct virtio_iommu_req_map map; + struct viommu_domain *vdomain = to_viommu_domain(domain); + + flags = (prot & IOMMU_READ ? VIRTIO_IOMMU_MAP_F_READ : 0) | + (prot & IOMMU_WRITE ? VIRTIO_IOMMU_MAP_F_WRITE : 0) | + (prot & IOMMU_MMIO ? VIRTIO_IOMMU_MAP_F_MMIO : 0); + + mapping = viommu_add_mapping(vdomain, iova, paddr, size, flags); + if (!mapping) + return -ENOMEM; + + map = (struct virtio_iommu_req_map) { + .head.type = VIRTIO_IOMMU_T_MAP, + .domain = cpu_to_le32(vdomain->id), + .virt_start = cpu_to_le64(iova), + .phys_start = cpu_to_le64(paddr), + .virt_end = cpu_to_le64(iova + size - 1), + .flags = cpu_to_le32(flags), + }; + + if (!vdomain->nr_endpoints) + return 0; + + ret = viommu_send_req_sync(vdomain->viommu, &map, sizeof(map)); + if (ret) + viommu_del_mappings(vdomain, iova, size); + + return ret; +} + +static size_t viommu_unmap(struct iommu_domain *domain, unsigned long iova, + size_t size) +{ + int ret = 0; + size_t unmapped; + struct virtio_iommu_req_unmap unmap; + struct viommu_domain *vdomain = to_viommu_domain(domain); + + unmapped = viommu_del_mappings(vdomain, iova, size); + if (unmapped < size) + return 0; + + /* Device already removed all mappings after detach. */ + if (!vdomain->nr_endpoints) + return unmapped; + + unmap = (struct virtio_iommu_req_unmap) { + .head.type = VIRTIO_IOMMU_T_UNMAP, + .domain = cpu_to_le32(vdomain->id), + .virt_start = cpu_to_le64(iova), + .virt_end = cpu_to_le64(iova + unmapped - 1), + }; + + ret = viommu_add_req(vdomain->viommu, &unmap, sizeof(unmap)); + return ret ? 0 : unmapped; +} + +static phys_addr_t viommu_iova_to_phys(struct iommu_domain *domain, + dma_addr_t iova) +{ + u64 paddr = 0; + unsigned long flags; + struct viommu_mapping *mapping; + struct interval_tree_node *node; + struct viommu_domain *vdomain = to_viommu_domain(domain); + + spin_lock_irqsave(&vdomain->mappings_lock, flags); + node = interval_tree_iter_first(&vdomain->mappings, iova, iova); + if (node) { + mapping = container_of(node, struct viommu_mapping, iova); + paddr = mapping->paddr + (iova - mapping->iova.start); + } + spin_unlock_irqrestore(&vdomain->mappings_lock, flags); + + return paddr; +} + +static void viommu_iotlb_sync(struct iommu_domain *domain) +{ + struct viommu_domain *vdomain = to_viommu_domain(domain); + + viommu_sync_req(vdomain->viommu); +} + +static void viommu_get_resv_regions(struct device *dev, struct list_head *head) +{ + struct iommu_resv_region *region; + int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; + + region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH, prot, + IOMMU_RESV_SW_MSI); + if (!region) + return; + + list_add_tail(®ion->list, head); + iommu_dma_get_resv_regions(dev, head); +} + +static void viommu_put_resv_regions(struct device *dev, struct list_head *head) +{ + struct iommu_resv_region *entry, *next; + + list_for_each_entry_safe(entry, next, head, list) + kfree(entry); +} + +static struct iommu_ops viommu_ops; +static struct virtio_driver virtio_iommu_drv; + +static int viommu_match_node(struct device *dev, void *data) +{ + return dev->parent->fwnode == data; +} + +static struct viommu_dev *viommu_get_by_fwnode(struct fwnode_handle *fwnode) +{ + struct device *dev = driver_find_device(&virtio_iommu_drv.driver, NULL, + fwnode, viommu_match_node); + put_device(dev); + + return dev ? dev_to_virtio(dev)->priv : NULL; +} + +static int viommu_add_device(struct device *dev) +{ + int ret; + struct iommu_group *group; + struct viommu_endpoint *vdev; + struct viommu_dev *viommu = NULL; + struct iommu_fwspec *fwspec = dev->iommu_fwspec; + + if (!fwspec || fwspec->ops != &viommu_ops) + return -ENODEV; + + viommu = viommu_get_by_fwnode(fwspec->iommu_fwnode); + if (!viommu) + return -ENODEV; + + vdev = kzalloc(sizeof(*vdev), GFP_KERNEL); + if (!vdev) + return -ENOMEM; + + vdev->viommu = viommu; + fwspec->iommu_priv = vdev; + + ret = iommu_device_link(&viommu->iommu, dev); + if (ret) + goto err_free_dev; + + /* + * Last step creates a default domain and attaches to it. Everything + * must be ready. + */ + group = iommu_group_get_for_dev(dev); + if (IS_ERR(group)) { + ret = PTR_ERR(group); + goto err_unlink_dev; + } + + iommu_group_put(group); + + return PTR_ERR_OR_ZERO(group); + +err_unlink_dev: + iommu_device_unlink(&viommu->iommu, dev); + +err_free_dev: + kfree(vdev); + + return ret; +} + +static void viommu_remove_device(struct device *dev) +{ + struct viommu_endpoint *vdev; + struct iommu_fwspec *fwspec = dev->iommu_fwspec; + + if (!fwspec || fwspec->ops != &viommu_ops) + return; + + vdev = fwspec->iommu_priv; + + iommu_group_remove_device(dev); + iommu_device_unlink(&vdev->viommu->iommu, dev); + kfree(vdev); +} + +static struct iommu_group *viommu_device_group(struct device *dev) +{ + if (dev_is_pci(dev)) + return pci_device_group(dev); + else + return generic_device_group(dev); +} + +static int viommu_of_xlate(struct device *dev, struct of_phandle_args *args) +{ + return iommu_fwspec_add_ids(dev, args->args, 1); +} + +static struct iommu_ops viommu_ops = { + .domain_alloc = viommu_domain_alloc, + .domain_free = viommu_domain_free, + .attach_dev = viommu_attach_dev, + .map = viommu_map, + .unmap = viommu_unmap, + .iova_to_phys = viommu_iova_to_phys, + .iotlb_sync = viommu_iotlb_sync, + .add_device = viommu_add_device, + .remove_device = viommu_remove_device, + .device_group = viommu_device_group, + .get_resv_regions = viommu_get_resv_regions, + .put_resv_regions = viommu_put_resv_regions, + .of_xlate = viommu_of_xlate, +}; + +static int viommu_init_vqs(struct viommu_dev *viommu) +{ + struct virtio_device *vdev = dev_to_virtio(viommu->dev); + const char *name = "request"; + void *ret; + + ret = virtio_find_single_vq(vdev, NULL, name); + if (IS_ERR(ret)) { + dev_err(viommu->dev, "cannot find VQ\n"); + return PTR_ERR(ret); + } + + viommu->vqs[VIOMMU_REQUEST_VQ] = ret; + + return 0; +} + +static int viommu_probe(struct virtio_device *vdev) +{ + struct device *parent_dev = vdev->dev.parent; + struct viommu_dev *viommu = NULL; + struct device *dev = &vdev->dev; + u64 input_start = 0; + u64 input_end = -1UL; + int ret; + + if (!virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) + return -ENODEV; + + viommu = devm_kzalloc(dev, sizeof(*viommu), GFP_KERNEL); + if (!viommu) + return -ENOMEM; + + spin_lock_init(&viommu->request_lock); + ida_init(&viommu->domain_ids); + viommu->dev = dev; + viommu->vdev = vdev; + INIT_LIST_HEAD(&viommu->requests); + + ret = viommu_init_vqs(viommu); + if (ret) + return ret; + + virtio_cread(vdev, struct virtio_iommu_config, page_size_mask, + &viommu->pgsize_bitmap); + + if (!viommu->pgsize_bitmap) { + ret = -EINVAL; + goto err_free_vqs; + } + + viommu->domain_bits = 32; + + /* Optional features */ + virtio_cread_feature(vdev, VIRTIO_IOMMU_F_INPUT_RANGE, + struct virtio_iommu_config, input_range.start, + &input_start); + + virtio_cread_feature(vdev, VIRTIO_IOMMU_F_INPUT_RANGE, + struct virtio_iommu_config, input_range.end, + &input_end); + + virtio_cread_feature(vdev, VIRTIO_IOMMU_F_DOMAIN_BITS, + struct virtio_iommu_config, domain_bits, + &viommu->domain_bits); + + viommu->geometry = (struct iommu_domain_geometry) { + .aperture_start = input_start, + .aperture_end = input_end, + .force_aperture = true, + }; + + viommu_ops.pgsize_bitmap = viommu->pgsize_bitmap; + + virtio_device_ready(vdev); + + ret = iommu_device_sysfs_add(&viommu->iommu, dev, NULL, "%s", + virtio_bus_name(vdev)); + if (ret) + goto err_free_vqs; + + iommu_device_set_ops(&viommu->iommu, &viommu_ops); + iommu_device_set_fwnode(&viommu->iommu, parent_dev->fwnode); + + iommu_device_register(&viommu->iommu); + +#ifdef CONFIG_PCI + if (pci_bus_type.iommu_ops != &viommu_ops) { + pci_request_acs(); + ret = bus_set_iommu(&pci_bus_type, &viommu_ops); + if (ret) + goto err_unregister; + } +#endif +#ifdef CONFIG_ARM_AMBA + if (amba_bustype.iommu_ops != &viommu_ops) { + ret = bus_set_iommu(&amba_bustype, &viommu_ops); + if (ret) + goto err_unregister; + } +#endif + if (platform_bus_type.iommu_ops != &viommu_ops) { + ret = bus_set_iommu(&platform_bus_type, &viommu_ops); + if (ret) + goto err_unregister; + } + + vdev->priv = viommu; + + dev_info(dev, "input address: %u bits\n", + order_base_2(viommu->geometry.aperture_end)); + dev_info(dev, "page mask: %#llx\n", viommu->pgsize_bitmap); + + return 0; + +err_unregister: + iommu_device_sysfs_remove(&viommu->iommu); + iommu_device_unregister(&viommu->iommu); +err_free_vqs: + vdev->config->del_vqs(vdev); + + return ret; +} + +static void viommu_remove(struct virtio_device *vdev) +{ + struct viommu_dev *viommu = vdev->priv; + + iommu_device_sysfs_remove(&viommu->iommu); + iommu_device_unregister(&viommu->iommu); + + /* Stop all virtqueues */ + vdev->config->reset(vdev); + vdev->config->del_vqs(vdev); + + dev_info(&vdev->dev, "device removed\n"); +} + +static void viommu_config_changed(struct virtio_device *vdev) +{ + dev_warn(&vdev->dev, "config changed\n"); +} + +static unsigned int features[] = { + VIRTIO_IOMMU_F_MAP_UNMAP, + VIRTIO_IOMMU_F_DOMAIN_BITS, + VIRTIO_IOMMU_F_INPUT_RANGE, +}; + +static struct virtio_device_id id_table[] = { + { VIRTIO_ID_IOMMU, VIRTIO_DEV_ANY_ID }, + { 0 }, +}; + +static struct virtio_driver virtio_iommu_drv = { + .driver.name = KBUILD_MODNAME, + .driver.owner = THIS_MODULE, + .id_table = id_table, + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), + .probe = viommu_probe, + .remove = viommu_remove, + .config_changed = viommu_config_changed, +}; + +module_virtio_driver(virtio_iommu_drv); + +MODULE_DESCRIPTION("Virtio IOMMU driver"); +MODULE_AUTHOR("Jean-Philippe Brucker "); +MODULE_LICENSE("GPL v2"); diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h index 6d5c3b2d4f4d..cfe47c5d9a56 100644 --- a/include/uapi/linux/virtio_ids.h +++ b/include/uapi/linux/virtio_ids.h @@ -43,5 +43,6 @@ #define VIRTIO_ID_INPUT 18 /* virtio input */ #define VIRTIO_ID_VSOCK 19 /* virtio vsock transport */ #define VIRTIO_ID_CRYPTO 20 /* virtio crypto */ +#define VIRTIO_ID_IOMMU 23 /* virtio IOMMU */ #endif /* _LINUX_VIRTIO_IDS_H */ diff --git a/include/uapi/linux/virtio_iommu.h b/include/uapi/linux/virtio_iommu.h new file mode 100644 index 000000000000..e808fc7fbe82 --- /dev/null +++ b/include/uapi/linux/virtio_iommu.h @@ -0,0 +1,101 @@ +/* SPDX-License-Identifier: BSD-3-Clause */ +/* + * Virtio-iommu definition v0.8 + * + * Copyright (C) 2018 Arm Ltd. + */ +#ifndef _UAPI_LINUX_VIRTIO_IOMMU_H +#define _UAPI_LINUX_VIRTIO_IOMMU_H + +#include + +/* Feature bits */ +#define VIRTIO_IOMMU_F_INPUT_RANGE 0 +#define VIRTIO_IOMMU_F_DOMAIN_BITS 1 +#define VIRTIO_IOMMU_F_MAP_UNMAP 2 +#define VIRTIO_IOMMU_F_BYPASS 3 + +struct virtio_iommu_config { + /* Supported page sizes */ + __u64 page_size_mask; + /* Supported IOVA range */ + struct virtio_iommu_range { + __u64 start; + __u64 end; + } input_range; + /* Max domain ID size */ + __u8 domain_bits; +}; + +/* Request types */ +#define VIRTIO_IOMMU_T_ATTACH 0x01 +#define VIRTIO_IOMMU_T_DETACH 0x02 +#define VIRTIO_IOMMU_T_MAP 0x03 +#define VIRTIO_IOMMU_T_UNMAP 0x04 + +/* Status types */ +#define VIRTIO_IOMMU_S_OK 0x00 +#define VIRTIO_IOMMU_S_IOERR 0x01 +#define VIRTIO_IOMMU_S_UNSUPP 0x02 +#define VIRTIO_IOMMU_S_DEVERR 0x03 +#define VIRTIO_IOMMU_S_INVAL 0x04 +#define VIRTIO_IOMMU_S_RANGE 0x05 +#define VIRTIO_IOMMU_S_NOENT 0x06 +#define VIRTIO_IOMMU_S_FAULT 0x07 + +struct virtio_iommu_req_head { + __u8 type; + __u8 reserved[3]; +}; + +struct virtio_iommu_req_tail { + __u8 status; + __u8 reserved[3]; +}; + +struct virtio_iommu_req_attach { + struct virtio_iommu_req_head head; + __le32 domain; + __le32 endpoint; + __u8 reserved[8]; + struct virtio_iommu_req_tail tail; +}; + +struct virtio_iommu_req_detach { + struct virtio_iommu_req_head head; + __le32 domain; + __le32 endpoint; + __u8 reserved[8]; + struct virtio_iommu_req_tail tail; +}; + +#define VIRTIO_IOMMU_MAP_F_READ (1 << 0) +#define VIRTIO_IOMMU_MAP_F_WRITE (1 << 1) +#define VIRTIO_IOMMU_MAP_F_EXEC (1 << 2) +#define VIRTIO_IOMMU_MAP_F_MMIO (1 << 3) + +#define VIRTIO_IOMMU_MAP_F_MASK (VIRTIO_IOMMU_MAP_F_READ | \ + VIRTIO_IOMMU_MAP_F_WRITE | \ + VIRTIO_IOMMU_MAP_F_EXEC | \ + VIRTIO_IOMMU_MAP_F_MMIO) + +struct virtio_iommu_req_map { + struct virtio_iommu_req_head head; + __le32 domain; + __le64 virt_start; + __le64 virt_end; + __le64 phys_start; + __le32 flags; + struct virtio_iommu_req_tail tail; +}; + +struct virtio_iommu_req_unmap { + struct virtio_iommu_req_head head; + __le32 domain; + __le64 virt_start; + __le64 virt_end; + __u8 reserved[4]; + struct virtio_iommu_req_tail tail; +}; + +#endif From patchwork Fri Oct 12 14:59:16 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983126 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcy6CSvz9s3T for ; Sat, 13 Oct 2018 02:01:06 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728917AbeJLWd4 (ORCPT ); Fri, 12 Oct 2018 18:33:56 -0400 Received: from foss.arm.com ([217.140.101.70]:52806 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728896AbeJLWd4 (ORCPT ); Fri, 12 Oct 2018 18:33:56 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id E8A831596; Fri, 12 Oct 2018 08:01:04 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 044A33F5BC; Fri, 12 Oct 2018 08:01:01 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 6/7] iommu/virtio: Add probe request Date: Fri, 12 Oct 2018 15:59:16 +0100 Message-Id: <20181012145917.6840-7-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org When the device offers the probe feature, send a probe request for each device managed by the IOMMU. Extract RESV_MEM information. When we encounter a MSI doorbell region, set it up as a IOMMU_RESV_MSI region. This will tell other subsystems that there is no need to map the MSI doorbell in the virtio-iommu, because MSIs bypass it. Signed-off-by: Jean-Philippe Brucker --- drivers/iommu/virtio-iommu.c | 147 ++++++++++++++++++++++++++++-- include/uapi/linux/virtio_iommu.h | 39 ++++++++ 2 files changed, 180 insertions(+), 6 deletions(-) diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 9fb38cd3b727..8eaf66770469 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -56,6 +56,7 @@ struct viommu_dev { struct iommu_domain_geometry geometry; u64 pgsize_bitmap; u8 domain_bits; + u32 probe_size; }; struct viommu_mapping { @@ -77,8 +78,10 @@ struct viommu_domain { }; struct viommu_endpoint { + struct device *dev; struct viommu_dev *viommu; struct viommu_domain *vdomain; + struct list_head resv_regions; }; struct viommu_request { @@ -129,6 +132,9 @@ static off_t viommu_get_req_offset(struct viommu_dev *viommu, { size_t tail_size = sizeof(struct virtio_iommu_req_tail); + if (req->type == VIRTIO_IOMMU_T_PROBE) + return len - viommu->probe_size - tail_size; + return len - tail_size; } @@ -414,6 +420,101 @@ static int viommu_replay_mappings(struct viommu_domain *vdomain) return ret; } +static int viommu_add_resv_mem(struct viommu_endpoint *vdev, + struct virtio_iommu_probe_resv_mem *mem, + size_t len) +{ + struct iommu_resv_region *region = NULL; + unsigned long prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; + + u64 start = le64_to_cpu(mem->start); + u64 end = le64_to_cpu(mem->end); + size_t size = end - start + 1; + + if (len < sizeof(*mem)) + return -EINVAL; + + switch (mem->subtype) { + default: + dev_warn(vdev->dev, "unknown resv mem subtype 0x%x\n", + mem->subtype); + /* Fall-through */ + case VIRTIO_IOMMU_RESV_MEM_T_RESERVED: + region = iommu_alloc_resv_region(start, size, 0, + IOMMU_RESV_RESERVED); + break; + case VIRTIO_IOMMU_RESV_MEM_T_MSI: + region = iommu_alloc_resv_region(start, size, prot, + IOMMU_RESV_MSI); + break; + } + + list_add(&vdev->resv_regions, ®ion->list); + return 0; +} + +static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev) +{ + int ret; + u16 type, len; + size_t cur = 0; + size_t probe_len; + struct virtio_iommu_req_probe *probe; + struct virtio_iommu_probe_property *prop; + struct iommu_fwspec *fwspec = dev->iommu_fwspec; + struct viommu_endpoint *vdev = fwspec->iommu_priv; + + if (!fwspec->num_ids) + return -EINVAL; + + probe_len = sizeof(*probe) + viommu->probe_size + + sizeof(struct virtio_iommu_req_tail); + probe = kzalloc(probe_len, GFP_KERNEL); + if (!probe) + return -ENOMEM; + + probe->head.type = VIRTIO_IOMMU_T_PROBE; + /* + * For now, assume that properties of an endpoint that outputs multiple + * IDs are consistent. Only probe the first one. + */ + probe->endpoint = cpu_to_le32(fwspec->ids[0]); + + ret = viommu_send_req_sync(viommu, probe, probe_len); + if (ret) + goto out_free; + + prop = (void *)probe->properties; + type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK; + + while (type != VIRTIO_IOMMU_PROBE_T_NONE && + cur < viommu->probe_size) { + len = le16_to_cpu(prop->length) + sizeof(*prop); + + switch (type) { + case VIRTIO_IOMMU_PROBE_T_RESV_MEM: + ret = viommu_add_resv_mem(vdev, (void *)prop, len); + break; + default: + dev_err(dev, "unknown viommu prop 0x%x\n", type); + } + + if (ret) + dev_err(dev, "failed to parse viommu prop 0x%x\n", type); + + cur += len; + if (cur >= viommu->probe_size) + break; + + prop = (void *)probe->properties + cur; + type = le16_to_cpu(prop->type) & VIRTIO_IOMMU_PROBE_T_MASK; + } + +out_free: + kfree(probe); + return ret; +} + /* IOMMU API */ static struct iommu_domain *viommu_domain_alloc(unsigned type) @@ -636,15 +737,33 @@ static void viommu_iotlb_sync(struct iommu_domain *domain) static void viommu_get_resv_regions(struct device *dev, struct list_head *head) { - struct iommu_resv_region *region; + struct iommu_resv_region *entry, *new_entry, *msi = NULL; + struct viommu_endpoint *vdev = dev->iommu_fwspec->iommu_priv; int prot = IOMMU_WRITE | IOMMU_NOEXEC | IOMMU_MMIO; - region = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH, prot, - IOMMU_RESV_SW_MSI); - if (!region) - return; + list_for_each_entry(entry, &vdev->resv_regions, list) { + /* + * If the device registered a bypass MSI windows, use it. + * Otherwise add a software-mapped region + */ + if (entry->type == IOMMU_RESV_MSI) + msi = entry; + + new_entry = kmemdup(entry, sizeof(*entry), GFP_KERNEL); + if (!new_entry) + return; + list_add_tail(&new_entry->list, head); + } + + if (!msi) { + msi = iommu_alloc_resv_region(MSI_IOVA_BASE, MSI_IOVA_LENGTH, + prot, IOMMU_RESV_SW_MSI); + if (!msi) + return; + + list_add_tail(&msi->list, head); + } - list_add_tail(®ion->list, head); iommu_dma_get_resv_regions(dev, head); } @@ -692,9 +811,18 @@ static int viommu_add_device(struct device *dev) if (!vdev) return -ENOMEM; + vdev->dev = dev; vdev->viommu = viommu; + INIT_LIST_HEAD(&vdev->resv_regions); fwspec->iommu_priv = vdev; + if (viommu->probe_size) { + /* Get additional information for this endpoint */ + ret = viommu_probe_endpoint(viommu, dev); + if (ret) + return ret; + } + ret = iommu_device_link(&viommu->iommu, dev); if (ret) goto err_free_dev; @@ -717,6 +845,7 @@ static int viommu_add_device(struct device *dev) iommu_device_unlink(&viommu->iommu, dev); err_free_dev: + viommu_put_resv_regions(dev, &vdev->resv_regions); kfree(vdev); return ret; @@ -734,6 +863,7 @@ static void viommu_remove_device(struct device *dev) iommu_group_remove_device(dev); iommu_device_unlink(&vdev->viommu->iommu, dev); + viommu_put_resv_regions(dev, &vdev->resv_regions); kfree(vdev); } @@ -832,6 +962,10 @@ static int viommu_probe(struct virtio_device *vdev) struct virtio_iommu_config, domain_bits, &viommu->domain_bits); + virtio_cread_feature(vdev, VIRTIO_IOMMU_F_PROBE, + struct virtio_iommu_config, probe_size, + &viommu->probe_size); + viommu->geometry = (struct iommu_domain_geometry) { .aperture_start = input_start, .aperture_end = input_end, @@ -913,6 +1047,7 @@ static unsigned int features[] = { VIRTIO_IOMMU_F_MAP_UNMAP, VIRTIO_IOMMU_F_DOMAIN_BITS, VIRTIO_IOMMU_F_INPUT_RANGE, + VIRTIO_IOMMU_F_PROBE, }; static struct virtio_device_id id_table[] = { diff --git a/include/uapi/linux/virtio_iommu.h b/include/uapi/linux/virtio_iommu.h index e808fc7fbe82..feed74586bb0 100644 --- a/include/uapi/linux/virtio_iommu.h +++ b/include/uapi/linux/virtio_iommu.h @@ -14,6 +14,7 @@ #define VIRTIO_IOMMU_F_DOMAIN_BITS 1 #define VIRTIO_IOMMU_F_MAP_UNMAP 2 #define VIRTIO_IOMMU_F_BYPASS 3 +#define VIRTIO_IOMMU_F_PROBE 4 struct virtio_iommu_config { /* Supported page sizes */ @@ -25,6 +26,9 @@ struct virtio_iommu_config { } input_range; /* Max domain ID size */ __u8 domain_bits; + __u8 padding[3]; + /* Probe buffer size */ + __u32 probe_size; }; /* Request types */ @@ -32,6 +36,7 @@ struct virtio_iommu_config { #define VIRTIO_IOMMU_T_DETACH 0x02 #define VIRTIO_IOMMU_T_MAP 0x03 #define VIRTIO_IOMMU_T_UNMAP 0x04 +#define VIRTIO_IOMMU_T_PROBE 0x05 /* Status types */ #define VIRTIO_IOMMU_S_OK 0x00 @@ -98,4 +103,38 @@ struct virtio_iommu_req_unmap { struct virtio_iommu_req_tail tail; }; +#define VIRTIO_IOMMU_PROBE_T_NONE 0 +#define VIRTIO_IOMMU_PROBE_T_RESV_MEM 1 + +#define VIRTIO_IOMMU_PROBE_T_MASK 0xfff + +struct virtio_iommu_probe_property { + __le16 type; + __le16 length; +}; + +#define VIRTIO_IOMMU_RESV_MEM_T_RESERVED 0 +#define VIRTIO_IOMMU_RESV_MEM_T_MSI 1 + +struct virtio_iommu_probe_resv_mem { + struct virtio_iommu_probe_property head; + __u8 subtype; + __u8 reserved[3]; + __le64 start; + __le64 end; +}; + +struct virtio_iommu_req_probe { + struct virtio_iommu_req_head head; + __le32 endpoint; + __u8 reserved[64]; + + __u8 properties[]; + + /* + * Tail follows the variable-length properties array. No padding, + * property lengths are all aligned on 8 bytes. + */ +}; + #endif From patchwork Fri Oct 12 14:59:17 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983127 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrd20DG4z9s4Z for ; Sat, 13 Oct 2018 02:01:10 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728896AbeJLWd7 (ORCPT ); Fri, 12 Oct 2018 18:33:59 -0400 Received: from foss.arm.com ([217.140.101.70]:52824 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728816AbeJLWd7 (ORCPT ); Fri, 12 Oct 2018 18:33:59 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 21DB715BF; Fri, 12 Oct 2018 08:01:08 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 320203F5BC; Fri, 12 Oct 2018 08:01:05 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 7/7] iommu/virtio: Add event queue Date: Fri, 12 Oct 2018 15:59:17 +0100 Message-Id: <20181012145917.6840-8-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org The event queue offers a way for the device to report access faults from endpoints. It is implemented on virtqueue #1. Whenever the host needs to signal a fault, it fills one of the buffers offered by the guest and interrupts it. Signed-off-by: Jean-Philippe Brucker --- drivers/iommu/virtio-iommu.c | 116 +++++++++++++++++++++++++++--- include/uapi/linux/virtio_iommu.h | 19 +++++ 2 files changed, 126 insertions(+), 9 deletions(-) diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c index 8eaf66770469..0fe8ed2a290c 100644 --- a/drivers/iommu/virtio-iommu.c +++ b/drivers/iommu/virtio-iommu.c @@ -29,7 +29,8 @@ #define MSI_IOVA_LENGTH 0x100000 #define VIOMMU_REQUEST_VQ 0 -#define VIOMMU_NR_VQS 1 +#define VIOMMU_EVENT_VQ 1 +#define VIOMMU_NR_VQS 2 /* * During development, it is convenient to time out rather than wait @@ -51,6 +52,7 @@ struct viommu_dev { struct virtqueue *vqs[VIOMMU_NR_VQS]; spinlock_t request_lock; struct list_head requests; + void *evts; /* Device configuration */ struct iommu_domain_geometry geometry; @@ -92,6 +94,15 @@ struct viommu_request { char buf[]; }; +#define VIOMMU_FAULT_RESV_MASK 0xffffff00 + +struct viommu_event { + union { + u32 head; + struct virtio_iommu_fault fault; + }; +}; + #define to_viommu_domain(domain) \ container_of(domain, struct viommu_domain, domain) @@ -515,6 +526,69 @@ static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev) return ret; } +static int viommu_fault_handler(struct viommu_dev *viommu, + struct virtio_iommu_fault *fault) +{ + char *reason_str; + + u8 reason = fault->reason; + u32 flags = le32_to_cpu(fault->flags); + u32 endpoint = le32_to_cpu(fault->endpoint); + u64 address = le64_to_cpu(fault->address); + + switch (reason) { + case VIRTIO_IOMMU_FAULT_R_DOMAIN: + reason_str = "domain"; + break; + case VIRTIO_IOMMU_FAULT_R_MAPPING: + reason_str = "page"; + break; + case VIRTIO_IOMMU_FAULT_R_UNKNOWN: + default: + reason_str = "unknown"; + break; + } + + /* TODO: find EP by ID and report_iommu_fault */ + if (flags & VIRTIO_IOMMU_FAULT_F_ADDRESS) + dev_err_ratelimited(viommu->dev, "%s fault from EP %u at %#llx [%s%s%s]\n", + reason_str, endpoint, address, + flags & VIRTIO_IOMMU_FAULT_F_READ ? "R" : "", + flags & VIRTIO_IOMMU_FAULT_F_WRITE ? "W" : "", + flags & VIRTIO_IOMMU_FAULT_F_EXEC ? "X" : ""); + else + dev_err_ratelimited(viommu->dev, "%s fault from EP %u\n", + reason_str, endpoint); + return 0; +} + +static void viommu_event_handler(struct virtqueue *vq) +{ + int ret; + unsigned int len; + struct scatterlist sg[1]; + struct viommu_event *evt; + struct viommu_dev *viommu = vq->vdev->priv; + + while ((evt = virtqueue_get_buf(vq, &len)) != NULL) { + if (len > sizeof(*evt)) { + dev_err(viommu->dev, + "invalid event buffer (len %u != %zu)\n", + len, sizeof(*evt)); + } else if (!(evt->head & VIOMMU_FAULT_RESV_MASK)) { + viommu_fault_handler(viommu, &evt->fault); + } + + sg_init_one(sg, evt, sizeof(*evt)); + ret = virtqueue_add_inbuf(vq, sg, 1, evt, GFP_ATOMIC); + if (ret) + dev_err(viommu->dev, "could not add event buffer\n"); + } + + if (!virtqueue_kick(vq)) + dev_err(viommu->dev, "kick failed\n"); +} + /* IOMMU API */ static struct iommu_domain *viommu_domain_alloc(unsigned type) @@ -899,16 +973,35 @@ static struct iommu_ops viommu_ops = { static int viommu_init_vqs(struct viommu_dev *viommu) { struct virtio_device *vdev = dev_to_virtio(viommu->dev); - const char *name = "request"; - void *ret; + const char *names[] = { "request", "event" }; + vq_callback_t *callbacks[] = { + NULL, /* No async requests */ + viommu_event_handler, + }; - ret = virtio_find_single_vq(vdev, NULL, name); - if (IS_ERR(ret)) { - dev_err(viommu->dev, "cannot find VQ\n"); - return PTR_ERR(ret); - } + return virtio_find_vqs(vdev, VIOMMU_NR_VQS, viommu->vqs, callbacks, + names, NULL); +} - viommu->vqs[VIOMMU_REQUEST_VQ] = ret; +static int viommu_fill_evtq(struct viommu_dev *viommu) +{ + int i, ret; + struct scatterlist sg[1]; + struct viommu_event *evts; + struct virtqueue *vq = viommu->vqs[VIOMMU_EVENT_VQ]; + size_t nr_evts = vq->num_free; + + viommu->evts = evts = devm_kmalloc_array(viommu->dev, nr_evts, + sizeof(*evts), GFP_KERNEL); + if (!evts) + return -ENOMEM; + + for (i = 0; i < nr_evts; i++) { + sg_init_one(sg, &evts[i], sizeof(*evts)); + ret = virtqueue_add_inbuf(vq, sg, 1, &evts[i], GFP_KERNEL); + if (ret) + return ret; + } return 0; } @@ -976,6 +1069,11 @@ static int viommu_probe(struct virtio_device *vdev) virtio_device_ready(vdev); + /* Populate the event queue with buffers */ + ret = viommu_fill_evtq(viommu); + if (ret) + goto err_free_vqs; + ret = iommu_device_sysfs_add(&viommu->iommu, dev, NULL, "%s", virtio_bus_name(vdev)); if (ret) diff --git a/include/uapi/linux/virtio_iommu.h b/include/uapi/linux/virtio_iommu.h index feed74586bb0..04647c266d6f 100644 --- a/include/uapi/linux/virtio_iommu.h +++ b/include/uapi/linux/virtio_iommu.h @@ -137,4 +137,23 @@ struct virtio_iommu_req_probe { */ }; +/* Fault types */ +#define VIRTIO_IOMMU_FAULT_R_UNKNOWN 0 +#define VIRTIO_IOMMU_FAULT_R_DOMAIN 1 +#define VIRTIO_IOMMU_FAULT_R_MAPPING 2 + +#define VIRTIO_IOMMU_FAULT_F_READ (1 << 0) +#define VIRTIO_IOMMU_FAULT_F_WRITE (1 << 1) +#define VIRTIO_IOMMU_FAULT_F_EXEC (1 << 2) +#define VIRTIO_IOMMU_FAULT_F_ADDRESS (1 << 8) + +struct virtio_iommu_fault { + __u8 reason; + __u8 reserved[3]; + __le32 flags; + __le32 endpoint; + __u8 reserved2[4]; + __le64 address; +}; + #endif