From ee071f67f7a103c66f85f68ffe083712929122e3 Mon Sep 17 00:00:00 2001 From: Viktor Prutyanov Date: Mon, 26 Jun 2023 12:12:57 +0300 Subject: [PATCH] vhost: register and change IOMMU flag depending on Device-TLB state The guest can disable or never enable Device-TLB. In these cases, it can't be used even if enabled in QEMU. So, check Device-TLB state before registering IOMMU notifier and select unmap flag depending on that. Also, implement a way to change IOMMU notifier flag if Device-TLB state is changed. Buglink: https://bugzilla.redhat.com/show_bug.cgi?id=2001312 Signed-off-by: Viktor Prutyanov Acked-by: Jason Wang Message-Id: <20230626091258.24453-2-viktor@daynix.com> Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/virtio/vhost-stub.c | 4 ++++ hw/virtio/vhost.c | 38 ++++++++++++++++++++++++++------------ include/hw/virtio/vhost.h | 1 + 3 files changed, 31 insertions(+), 12 deletions(-) diff --git a/hw/virtio/vhost-stub.c b/hw/virtio/vhost-stub.c index c175148fce..aa858ef3fb 100644 --- a/hw/virtio/vhost-stub.c +++ b/hw/virtio/vhost-stub.c @@ -15,3 +15,7 @@ bool vhost_user_init(VhostUserState *user, CharBackend *chr, Error **errp) void vhost_user_cleanup(VhostUserState *user) { } + +void vhost_toggle_device_iotlb(VirtIODevice *vdev) +{ +} diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c index 82394331bf..abf0d03c8d 100644 --- a/hw/virtio/vhost.c +++ b/hw/virtio/vhost.c @@ -780,7 +780,6 @@ static void vhost_iommu_region_add(MemoryListener *listener, Int128 end; int iommu_idx; IOMMUMemoryRegion *iommu_mr; - int ret; if (!memory_region_is_iommu(section->mr)) { return; @@ -795,7 +794,9 @@ 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->device_iotlb_enabled ? + IOMMU_NOTIFIER_DEVIOTLB_UNMAP : + IOMMU_NOTIFIER_UNMAP, section->offset_within_region, int128_get64(end), iommu_idx); @@ -803,16 +804,8 @@ 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); - if (ret) { - /* - * Some vIOMMUs do not support dev-iotlb yet. If so, try to use the - * UNMAP legacy message - */ - iommu->n.notifier_flags = IOMMU_NOTIFIER_UNMAP; - memory_region_register_iommu_notifier(section->mr, &iommu->n, - &error_fatal); - } + memory_region_register_iommu_notifier(section->mr, &iommu->n, + &error_fatal); QLIST_INSERT_HEAD(&dev->iommu_list, iommu, iommu_next); /* TODO: can replay help performance here? */ } @@ -840,6 +833,27 @@ static void vhost_iommu_region_del(MemoryListener *listener, } } +void vhost_toggle_device_iotlb(VirtIODevice *vdev) +{ + VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); + struct vhost_dev *dev; + struct vhost_iommu *iommu; + + if (vdev->vhost_started) { + dev = vdc->get_vhost(vdev); + } else { + return; + } + + QLIST_FOREACH(iommu, &dev->iommu_list, iommu_next) { + memory_region_unregister_iommu_notifier(iommu->mr, &iommu->n); + iommu->n.notifier_flags = vdev->device_iotlb_enabled ? + IOMMU_NOTIFIER_DEVIOTLB_UNMAP : IOMMU_NOTIFIER_UNMAP; + memory_region_register_iommu_notifier(iommu->mr, &iommu->n, + &error_fatal); + } +} + static int vhost_virtqueue_set_addr(struct vhost_dev *dev, struct vhost_virtqueue *vq, unsigned idx, bool enable_log) diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h index f7f10c8fb7..6a173cb9fa 100644 --- a/include/hw/virtio/vhost.h +++ b/include/hw/virtio/vhost.h @@ -320,6 +320,7 @@ bool vhost_has_free_slot(void); int vhost_net_set_backend(struct vhost_dev *hdev, struct vhost_vring_file *file); +void vhost_toggle_device_iotlb(VirtIODevice *vdev); int vhost_device_iotlb_miss(struct vhost_dev *dev, uint64_t iova, int write); int vhost_virtqueue_start(struct vhost_dev *dev, struct VirtIODevice *vdev, -- 2.11.0