Michael S. Tsirkin
2020-May-12 14:53 UTC
[PATCH v5] iommu/virtio: Use page size bitmap supported by endpoint
On Tue, May 05, 2020 at 03:00:04PM +0530, Bharat Bhushan wrote:> Different endpoint can support different page size, probe > endpoint if it supports specific page size otherwise use > global page sizes. > > Signed-off-by: Bharat Bhushan <bbhushan2 at marvell.com> > --- > v4->v5: > - Rebase to Linux v5.7-rc4 > > v3->v4: > - Fix whitespace error > > v2->v3: > - Fixed error return for incompatible endpoint > - __u64 changed to __le64 in header file > > drivers/iommu/virtio-iommu.c | 48 ++++++++++++++++++++++++++++--- > include/uapi/linux/virtio_iommu.h | 7 +++++ > 2 files changed, 51 insertions(+), 4 deletions(-) > > diff --git a/drivers/iommu/virtio-iommu.c b/drivers/iommu/virtio-iommu.c > index d5cac4f46ca5..9513d2ab819e 100644 > --- a/drivers/iommu/virtio-iommu.c > +++ b/drivers/iommu/virtio-iommu.c > @@ -78,6 +78,7 @@ struct viommu_endpoint { > struct viommu_dev *viommu; > struct viommu_domain *vdomain; > struct list_head resv_regions; > + u64 pgsize_bitmap; > }; > > struct viommu_request { > @@ -415,6 +416,19 @@ static int viommu_replay_mappings(struct viommu_domain *vdomain) > return ret; > } > > +static int viommu_set_pgsize_bitmap(struct viommu_endpoint *vdev, > + struct virtio_iommu_probe_pgsize_mask *mask, > + size_t len) > +{ > + u64 pgsize_bitmap = le64_to_cpu(mask->pgsize_bitmap); > + > + if (len < sizeof(*mask)) > + return -EINVAL; > + > + vdev->pgsize_bitmap = pgsize_bitmap; > + return 0; > +} > + > static int viommu_add_resv_mem(struct viommu_endpoint *vdev, > struct virtio_iommu_probe_resv_mem *mem, > size_t len) > @@ -499,6 +513,9 @@ static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev) > case VIRTIO_IOMMU_PROBE_T_RESV_MEM: > ret = viommu_add_resv_mem(vdev, (void *)prop, len); > break; > + case VIRTIO_IOMMU_PROBE_T_PAGE_SIZE_MASK: > + ret = viommu_set_pgsize_bitmap(vdev, (void *)prop, len); > + break; > default: > dev_err(dev, "unknown viommu prop 0x%x\n", type); > }So given this is necessary early in boot, how about we add this in the config space? And maybe ACPI too ...> @@ -630,7 +647,7 @@ static int viommu_domain_finalise(struct viommu_endpoint *vdev, > > vdomain->id = (unsigned int)ret; > > - domain->pgsize_bitmap = viommu->pgsize_bitmap; > + domain->pgsize_bitmap = vdev->pgsize_bitmap; > domain->geometry = viommu->geometry; > > vdomain->map_flags = viommu->map_flags; > @@ -654,6 +671,29 @@ static void viommu_domain_free(struct iommu_domain *domain) > kfree(vdomain); > } > > +/* > + * Check whether the endpoint's capabilities are compatible with other > + * endpoints in the domain. Report any inconsistency. > + */ > +static bool viommu_endpoint_is_compatible(struct viommu_endpoint *vdev, > + struct viommu_domain *vdomain) > +{ > + struct device *dev = vdev->dev; > + > + if (vdomain->viommu != vdev->viommu) { > + dev_err(dev, "cannot attach to foreign vIOMMU\n"); > + return false; > + } > + > + if (vdomain->domain.pgsize_bitmap != vdev->pgsize_bitmap) { > + dev_err(dev, "incompatible domain bitmap 0x%lx != 0x%llx\n", > + vdomain->domain.pgsize_bitmap, vdev->pgsize_bitmap); > + return false; > + } > + > + return true; > +} > + > static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev) > { > int i; > @@ -670,9 +710,8 @@ static int viommu_attach_dev(struct iommu_domain *domain, struct device *dev) > * owns it. > */ > ret = viommu_domain_finalise(vdev, domain); > - } else if (vdomain->viommu != vdev->viommu) { > - dev_err(dev, "cannot attach to foreign vIOMMU\n"); > - ret = -EXDEV; > + } else if (!viommu_endpoint_is_compatible(vdev, vdomain)) { > + ret = -EINVAL; > } > mutex_unlock(&vdomain->mutex); > > @@ -886,6 +925,7 @@ static int viommu_add_device(struct device *dev) > > vdev->dev = dev; > vdev->viommu = viommu; > + vdev->pgsize_bitmap = viommu->pgsize_bitmap; > INIT_LIST_HEAD(&vdev->resv_regions); > dev_iommu_priv_set(dev, vdev); > > diff --git a/include/uapi/linux/virtio_iommu.h b/include/uapi/linux/virtio_iommu.h > index 48e3c29223b5..2cced7accc99 100644 > --- a/include/uapi/linux/virtio_iommu.h > +++ b/include/uapi/linux/virtio_iommu.h > @@ -111,6 +111,7 @@ struct virtio_iommu_req_unmap { > > #define VIRTIO_IOMMU_PROBE_T_NONE 0 > #define VIRTIO_IOMMU_PROBE_T_RESV_MEM 1 > +#define VIRTIO_IOMMU_PROBE_T_PAGE_SIZE_MASK 2 > > #define VIRTIO_IOMMU_PROBE_T_MASK 0xfff > > @@ -119,6 +120,12 @@ struct virtio_iommu_probe_property { > __le16 length; > }; > > +struct virtio_iommu_probe_pgsize_mask { > + struct virtio_iommu_probe_property head; > + __u8 reserved[4]; > + __le64 pgsize_bitmap; > +}; > + > #define VIRTIO_IOMMU_RESV_MEM_T_RESERVED 0 > #define VIRTIO_IOMMU_RESV_MEM_T_MSI 1 > > -- > 2.17.1
Jean-Philippe Brucker
2020-May-12 16:47 UTC
[PATCH v5] iommu/virtio: Use page size bitmap supported by endpoint
On Tue, May 12, 2020 at 10:53:39AM -0400, Michael S. Tsirkin wrote:> > static int viommu_add_resv_mem(struct viommu_endpoint *vdev, > > struct virtio_iommu_probe_resv_mem *mem, > > size_t len) > > @@ -499,6 +513,9 @@ static int viommu_probe_endpoint(struct viommu_dev *viommu, struct device *dev) > > case VIRTIO_IOMMU_PROBE_T_RESV_MEM: > > ret = viommu_add_resv_mem(vdev, (void *)prop, len); > > break; > > + case VIRTIO_IOMMU_PROBE_T_PAGE_SIZE_MASK: > > + ret = viommu_set_pgsize_bitmap(vdev, (void *)prop, len); > > + break; > > default: > > dev_err(dev, "unknown viommu prop 0x%x\n", type); > > } > > So given this is necessary early in boot, how about we > add this in the config space? And maybe ACPI too ...A page_size_mask field is already in the config space and applies to all endpoints. Here we add a property to override the global value for individual endpoints. It can be necessary when mixing physical (pass- through) and virtual endpoints under the same virtio-iommu device. Thanks, Jean