diff options
Diffstat (limited to 'hw/virtio/virtio-iommu.c')
| -rw-r--r-- | hw/virtio/virtio-iommu.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c index 78e07aa40a..fc5c75d693 100644 --- a/hw/virtio/virtio-iommu.c +++ b/hw/virtio/virtio-iommu.c @@ -899,6 +899,55 @@ static int virtio_iommu_notify_flag_changed(IOMMUMemoryRegion *iommu_mr, return 0; } +/* + * The default mask (TARGET_PAGE_MASK) is the smallest supported guest granule, + * for example 0xfffffffffffff000. When an assigned device has page size + * restrictions due to the hardware IOMMU configuration, apply this restriction + * to the mask. + */ +static int virtio_iommu_set_page_size_mask(IOMMUMemoryRegion *mr, + uint64_t new_mask, + Error **errp) +{ + IOMMUDevice *sdev = container_of(mr, IOMMUDevice, iommu_mr); + VirtIOIOMMU *s = sdev->viommu; + uint64_t cur_mask = s->config.page_size_mask; + + trace_virtio_iommu_set_page_size_mask(mr->parent_obj.name, cur_mask, + new_mask); + + if ((cur_mask & new_mask) == 0) { + error_setg(errp, "virtio-iommu page mask 0x%"PRIx64 + " is incompatible with mask 0x%"PRIx64, cur_mask, new_mask); + return -1; + } + + /* + * After the machine is finalized, we can't change the mask anymore. If by + * chance the hotplugged device supports the same granule, we can still + * accept it. Having a different masks is possible but the guest will use + * sub-optimal block sizes, so warn about it. + */ + if (qdev_hotplug) { + int new_granule = ctz64(new_mask); + int cur_granule = ctz64(cur_mask); + + if (new_granule != cur_granule) { + error_setg(errp, "virtio-iommu page mask 0x%"PRIx64 + " is incompatible with mask 0x%"PRIx64, cur_mask, + new_mask); + return -1; + } else if (new_mask != cur_mask) { + warn_report("virtio-iommu page mask 0x%"PRIx64 + " does not match 0x%"PRIx64, cur_mask, new_mask); + } + return 0; + } + + s->config.page_size_mask &= new_mask; + return 0; +} + static void virtio_iommu_device_realize(DeviceState *dev, Error **errp) { VirtIODevice *vdev = VIRTIO_DEVICE(dev); @@ -1130,6 +1179,7 @@ static void virtio_iommu_memory_region_class_init(ObjectClass *klass, imrc->translate = virtio_iommu_translate; imrc->replay = virtio_iommu_replay; imrc->notify_flag_changed = virtio_iommu_notify_flag_changed; + imrc->iommu_set_page_size_mask = virtio_iommu_set_page_size_mask; } static const TypeInfo virtio_iommu_info = { |