| Message ID | 20230424112147.17083-5-viktor@daynix.com |
|---|---|
| State | New |
| Headers | show |
| Series | [RFC,1/4] pci: add handling of Enable bit in ATS Control Register | expand |
在 2023/4/24 19:21, Viktor Prutyanov 写道: > The guest can disable or never enable ATS. In these cases, Device-TLB > can't be used even if enabled in QEMU. So, check ATS state before > registering IOMMU notifier and select flag depending on that. Also, > change IOMMU notifier flag if ATS state is changed. > > Signed-off-by: Viktor Prutyanov <viktor@daynix.com> > --- > hw/virtio/vhost.c | 23 +++++++++++++++++++++-- > 1 file changed, 21 insertions(+), 2 deletions(-) > > diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c > index eb8c4c378c..1b14937020 100644 > --- a/hw/virtio/vhost.c > +++ b/hw/virtio/vhost.c > @@ -796,7 +796,9 @@ static void vhost_iommu_region_add(MemoryListener *listener, > iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, > MEMTXATTRS_UNSPECIFIED); > iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, > - IOMMU_NOTIFIER_DEVIOTLB_UNMAP, > + dev->vdev->ats_enabled ? > + IOMMU_NOTIFIER_DEVIOTLB_UNMAP : > + IOMMU_NOTIFIER_UNMAP, > section->offset_within_region, > int128_get64(end), > iommu_idx); > @@ -804,7 +806,8 @@ static void vhost_iommu_region_add(MemoryListener *listener, > iommu->iommu_offset = section->offset_within_address_space - > section->offset_within_region; > iommu->hdev = dev; > - ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, NULL); > + ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, > + dev->vdev->ats_enabled ? NULL : &error_fatal); > if (ret) { > /* > * Some vIOMMUs do not support dev-iotlb yet. If so, try to use the > @@ -818,6 +821,19 @@ static void vhost_iommu_region_add(MemoryListener *listener, > /* TODO: can replay help performance here? */ > } > > +static void vhost_deviotlb_ctrl_trigger(bool enable, struct VirtIODevice *vdev) > +{ > + VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); > + struct vhost_dev *hdev = vdc->get_vhost(vdev); > + struct vhost_iommu *iommu; > + > + QLIST_FOREACH(iommu, &hdev->iommu_list, iommu_next) { > + iommu->n.notifier_flags = enable ? > + IOMMU_NOTIFIER_DEVIOTLB_UNMAP : IOMMU_NOTIFIER_UNMAP; > + memory_region_iommu_notify_flags_changed(iommu->mr); > + } > +} > + > static void vhost_iommu_region_del(MemoryListener *listener, > MemoryRegionSection *section) > { > @@ -2000,6 +2016,8 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) > struct vhost_virtqueue *vq = hdev->vqs + i; > vhost_device_iotlb_miss(hdev, vq->used_phys, true); > } > + > + vdev->ats_ctrl_trigger = vhost_deviotlb_ctrl_trigger; Changing virtio method in the vhost seems a layer violation. I wonder if the following is better 1) have a virtio-net method in VirtioDeviceClass as ats trigger 2) call vhost_ops to enable/disable device IOTLB in this ats trigger (and do nothing if there's no vhost attached) Thanks > } > vhost_start_config_intr(hdev); > return 0; > @@ -2055,6 +2073,7 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) > hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); > } > memory_listener_unregister(&hdev->iommu_listener); > + vdev->ats_ctrl_trigger = NULL; > } > vhost_stop_config_intr(hdev); > vhost_log_put(hdev, true);
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index eb8c4c378c..1b14937020 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -796,7 +796,9 @@ static void vhost_iommu_region_add(MemoryListener *listener, iommu_idx = memory_region_iommu_attrs_to_index(iommu_mr, MEMTXATTRS_UNSPECIFIED); iommu_notifier_init(&iommu->n, vhost_iommu_unmap_notify, - IOMMU_NOTIFIER_DEVIOTLB_UNMAP, + dev->vdev->ats_enabled ? + IOMMU_NOTIFIER_DEVIOTLB_UNMAP : + IOMMU_NOTIFIER_UNMAP, section->offset_within_region, int128_get64(end), iommu_idx); @@ -804,7 +806,8 @@ static void vhost_iommu_region_add(MemoryListener *listener, iommu->iommu_offset = section->offset_within_address_space - section->offset_within_region; iommu->hdev = dev; - ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, NULL); + ret = memory_region_register_iommu_notifier(section->mr, &iommu->n, + dev->vdev->ats_enabled ? NULL : &error_fatal); if (ret) { /* * Some vIOMMUs do not support dev-iotlb yet. If so, try to use the @@ -818,6 +821,19 @@ static void vhost_iommu_region_add(MemoryListener *listener, /* TODO: can replay help performance here? */ } +static void vhost_deviotlb_ctrl_trigger(bool enable, struct VirtIODevice *vdev) +{ + VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); + struct vhost_dev *hdev = vdc->get_vhost(vdev); + struct vhost_iommu *iommu; + + QLIST_FOREACH(iommu, &hdev->iommu_list, iommu_next) { + iommu->n.notifier_flags = enable ? + IOMMU_NOTIFIER_DEVIOTLB_UNMAP : IOMMU_NOTIFIER_UNMAP; + memory_region_iommu_notify_flags_changed(iommu->mr); + } +} + static void vhost_iommu_region_del(MemoryListener *listener, MemoryRegionSection *section) { @@ -2000,6 +2016,8 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) struct vhost_virtqueue *vq = hdev->vqs + i; vhost_device_iotlb_miss(hdev, vq->used_phys, true); } + + vdev->ats_ctrl_trigger = vhost_deviotlb_ctrl_trigger; } vhost_start_config_intr(hdev); return 0; @@ -2055,6 +2073,7 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev, bool vrings) hdev->vhost_ops->vhost_set_iotlb_callback(hdev, false); } memory_listener_unregister(&hdev->iommu_listener); + vdev->ats_ctrl_trigger = NULL; } vhost_stop_config_intr(hdev); vhost_log_put(hdev, true);
The guest can disable or never enable ATS. In these cases, Device-TLB can't be used even if enabled in QEMU. So, check ATS state before registering IOMMU notifier and select flag depending on that. Also, change IOMMU notifier flag if ATS state is changed. Signed-off-by: Viktor Prutyanov <viktor@daynix.com> --- hw/virtio/vhost.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-)