From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jean-Philippe Brucker Subject: [RFC PATCH kvmtool 08/15] virtio: add vIOMMU instance for virtio devices Date: Fri, 7 Apr 2017 20:24:48 +0100 Message-ID: <20170407192455.26814-9-jean-philippe.brucker@arm.com> References: <20170407191747.26618-1-jean-philippe.brucker@arm.com> <20170407192455.26814-1-jean-philippe.brucker@arm.com> Cc: cdall@linaro.org, will.deacon@arm.com, robin.murphy@arm.com, lorenzo.pieralisi@arm.com, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, alex.williamson@redhat.com, marc.zyngier@arm.com To: iommu@lists.linux-foundation.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, virtio-dev@lists.oasis-open.org Return-path: Received: from foss.arm.com ([217.140.101.70]:60880 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934237AbdDGTYX (ORCPT ); Fri, 7 Apr 2017 15:24:23 -0400 In-Reply-To: <20170407192455.26814-1-jean-philippe.brucker@arm.com> Sender: kvm-owner@vger.kernel.org List-ID: Virtio devices can now opt-in to use an IOMMU, by setting the use_iommu field. None of this will work in the current state, since virtio devices still access memory linearly. A subsequent patch implements sg accesses. Signed-off-by: Jean-Philippe Brucker --- include/kvm/virtio-mmio.h | 1 + include/kvm/virtio-pci.h | 1 + include/kvm/virtio.h | 13 ++++++++++++ virtio/core.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++ virtio/mmio.c | 27 ++++++++++++++++++++++++ virtio/pci.c | 26 ++++++++++++++++++++++++ 6 files changed, 120 insertions(+) diff --git a/include/kvm/virtio-mmio.h b/include/kvm/virtio-mmio.h index 835f421b..c25a4fd7 100644 --- a/include/kvm/virtio-mmio.h +++ b/include/kvm/virtio-mmio.h @@ -44,6 +44,7 @@ struct virtio_mmio_hdr { struct virtio_mmio { u32 addr; void *dev; + struct virtio_device *vdev; struct kvm *kvm; u8 irq; struct virtio_mmio_hdr hdr; diff --git a/include/kvm/virtio-pci.h b/include/kvm/virtio-pci.h index b70cadd8..26772f74 100644 --- a/include/kvm/virtio-pci.h +++ b/include/kvm/virtio-pci.h @@ -22,6 +22,7 @@ struct virtio_pci { struct pci_device_header pci_hdr; struct device_header dev_hdr; void *dev; + struct virtio_device *vdev; struct kvm *kvm; u16 port_addr; diff --git a/include/kvm/virtio.h b/include/kvm/virtio.h index 24c0c487..9f2ff237 100644 --- a/include/kvm/virtio.h +++ b/include/kvm/virtio.h @@ -9,6 +9,7 @@ #include #include +#include "kvm/iommu.h" #include "kvm/kvm.h" #define VIRTIO_IRQ_LOW 0 @@ -137,10 +138,12 @@ enum virtio_trans { }; struct virtio_device { + bool use_iommu; bool use_vhost; void *virtio; struct virtio_ops *ops; u16 endian; + void *iotlb; }; struct virtio_ops { @@ -182,4 +185,14 @@ static inline void virtio_init_device_vq(struct kvm *kvm, vring_init(&vq->vring, nr_descs, p, align); } +/* + * These are callbacks for IOMMU operations on virtio devices. They are not + * operations on the virtio-iommu device. Confusing, I know. + */ +const struct iommu_properties * +virtio__iommu_get_properties(struct device_header *dev); + +int virtio__iommu_attach(void *, struct virtio_device *vdev, int flags); +int virtio__iommu_detach(void *, struct virtio_device *vdev); + #endif /* KVM__VIRTIO_H */ diff --git a/virtio/core.c b/virtio/core.c index d6ac289d..32bd4ebc 100644 --- a/virtio/core.c +++ b/virtio/core.c @@ -6,11 +6,16 @@ #include "kvm/guest_compat.h" #include "kvm/barrier.h" #include "kvm/virtio.h" +#include "kvm/virtio-iommu.h" #include "kvm/virtio-pci.h" #include "kvm/virtio-mmio.h" #include "kvm/util.h" #include "kvm/kvm.h" +static void *iommu = NULL; +static struct iommu_properties iommu_props = { + .name = "viommu-virtio", +}; const char* virtio_trans_name(enum virtio_trans trans) { @@ -198,6 +203,41 @@ bool virtio_queue__should_signal(struct virt_queue *vq) return false; } +const struct iommu_properties * +virtio__iommu_get_properties(struct device_header *dev) +{ + return &iommu_props; +} + +int virtio__iommu_attach(void *priv, struct virtio_device *vdev, int flags) +{ + struct virtio_tlb *iotlb = priv; + + if (!iotlb) + return -ENOMEM; + + if (vdev->iotlb) { + pr_err("device already attached"); + return -EINVAL; + } + + vdev->iotlb = iotlb; + + return 0; +} + +int virtio__iommu_detach(void *priv, struct virtio_device *vdev) +{ + if (vdev->iotlb != priv) { + pr_err("wrong iotlb"); /* bug */ + return -EINVAL; + } + + vdev->iotlb = NULL; + + return 0; +} + int virtio_init(struct kvm *kvm, void *dev, struct virtio_device *vdev, struct virtio_ops *ops, enum virtio_trans trans, int device_id, int subsys_id, int class) @@ -233,6 +273,18 @@ int virtio_init(struct kvm *kvm, void *dev, struct virtio_device *vdev, return -1; }; + if (!iommu && vdev->use_iommu) { + iommu_props.pgsize_mask = ~(PAGE_SIZE - 1); + /* + * With legacy MMIO, we only have 32-bit to hold the vring PFN. + * This limits the IOVA size to (32 + 12) = 44 bits, when using + * 4k pages. + */ + iommu_props.input_addr_size = 44; + iommu = viommu_register(kvm, &iommu_props); + } + + return 0; } diff --git a/virtio/mmio.c b/virtio/mmio.c index 16b44fbb..24a14a71 100644 --- a/virtio/mmio.c +++ b/virtio/mmio.c @@ -1,4 +1,5 @@ #include "kvm/devices.h" +#include "kvm/virtio-iommu.h" #include "kvm/virtio-mmio.h" #include "kvm/ioeventfd.h" #include "kvm/iommu.h" @@ -286,6 +287,30 @@ void virtio_mmio_assign_irq(struct device_header *dev_hdr) vmmio->irq = irq__alloc_line(); } +#define mmio_dev_to_virtio(dev_hdr) \ + container_of(dev_hdr, struct virtio_mmio, dev_hdr)->vdev + +static int virtio_mmio_iommu_attach(void *priv, struct device_header *dev_hdr, + int flags) +{ + return virtio__iommu_attach(priv, mmio_dev_to_virtio(dev_hdr), flags); +} + +static int virtio_mmio_iommu_detach(void *priv, struct device_header *dev_hdr) +{ + return virtio__iommu_detach(priv, mmio_dev_to_virtio(dev_hdr)); +} + +static struct iommu_ops virtio_mmio_iommu_ops = { + .get_properties = virtio__iommu_get_properties, + .alloc_address_space = iommu_alloc_address_space, + .free_address_space = iommu_free_address_space, + .attach = virtio_mmio_iommu_attach, + .detach = virtio_mmio_iommu_detach, + .map = iommu_map, + .unmap = iommu_unmap, +}; + int virtio_mmio_init(struct kvm *kvm, void *dev, struct virtio_device *vdev, int device_id, int subsys_id, int class) { @@ -294,6 +319,7 @@ int virtio_mmio_init(struct kvm *kvm, void *dev, struct virtio_device *vdev, vmmio->addr = virtio_mmio_get_io_space_block(VIRTIO_MMIO_IO_SIZE); vmmio->kvm = kvm; vmmio->dev = dev; + vmmio->vdev = vdev; kvm__register_mmio(kvm, vmmio->addr, VIRTIO_MMIO_IO_SIZE, false, virtio_mmio_mmio_callback, vdev); @@ -309,6 +335,7 @@ int virtio_mmio_init(struct kvm *kvm, void *dev, struct virtio_device *vdev, vmmio->dev_hdr = (struct device_header) { .bus_type = DEVICE_BUS_MMIO, .data = generate_virtio_mmio_fdt_node, + .iommu_ops = vdev->use_iommu ? &virtio_mmio_iommu_ops : NULL, }; device__register(&vmmio->dev_hdr); diff --git a/virtio/pci.c b/virtio/pci.c index b6ef389e..674d5143 100644 --- a/virtio/pci.c +++ b/virtio/pci.c @@ -408,6 +408,30 @@ static void virtio_pci__io_mmio_callback(struct kvm_cpu *vcpu, kvm__emulate_io(vcpu, port, data, direction, len, 1); } +#define pci_dev_to_virtio(dev_hdr) \ + (container_of(dev_hdr, struct virtio_pci, dev_hdr)->vdev) + +static int virtio_pci_iommu_attach(void *priv, struct device_header *dev_hdr, + int flags) +{ + return virtio__iommu_attach(priv, pci_dev_to_virtio(dev_hdr), flags); +} + +static int virtio_pci_iommu_detach(void *priv, struct device_header *dev_hdr) +{ + return virtio__iommu_detach(priv, pci_dev_to_virtio(dev_hdr)); +} + +static struct iommu_ops virtio_pci_iommu_ops = { + .get_properties = virtio__iommu_get_properties, + .alloc_address_space = iommu_alloc_address_space, + .free_address_space = iommu_free_address_space, + .attach = virtio_pci_iommu_attach, + .detach = virtio_pci_iommu_detach, + .map = iommu_map, + .unmap = iommu_unmap, +}; + int virtio_pci__init(struct kvm *kvm, void *dev, struct virtio_device *vdev, int device_id, int subsys_id, int class) { @@ -416,6 +440,7 @@ int virtio_pci__init(struct kvm *kvm, void *dev, struct virtio_device *vdev, vpci->kvm = kvm; vpci->dev = dev; + vpci->vdev = vdev; r = ioport__register(kvm, IOPORT_EMPTY, &virtio_pci__io_ops, IOPORT_SIZE, vdev); if (r < 0) @@ -461,6 +486,7 @@ int virtio_pci__init(struct kvm *kvm, void *dev, struct virtio_device *vdev, vpci->dev_hdr = (struct device_header) { .bus_type = DEVICE_BUS_PCI, .data = &vpci->pci_hdr, + .iommu_ops = vdev->use_iommu ? &virtio_pci_iommu_ops : NULL, }; vpci->pci_hdr.msix.cap = PCI_CAP_ID_MSIX; -- 2.12.1