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 <bbhush...@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); } @@ -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