[RFC,08/19] vfio-user: VFIO container setup & teardown

Commit Message

Elena Ufimtseva July 19, 2021, 6:27 a.m. UTC

From: John G Johnson <[e-mail]>

Create SW-emulated containers and groups for vfio-user
in lieu of the host IOMMU based ones used by the kernel
driver VFIO implementation.

Signed-off-by: Elena Ufimtseva <[e-mail]>
Signed-off-by: John G Johnson <[e-mail]>
Signed-off-by: Jagannathan Raman <[e-mail]>
---
 include/hw/vfio/vfio-common.h |  3 ++
 hw/vfio/common.c              | 70 +++++++++++++++++++++++++++++++++++
 hw/vfio/pci.c                 | 19 ++++++++++
 3 files changed, 92 insertions(+)

Patch

diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index f43dc6e5d0..491a92b4f5 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -90,6 +90,7 @@  typedef struct VFIOContainer {
     uint64_t max_dirty_bitmap_size;
     unsigned long pgsizes;
     unsigned int dma_max_mappings;
+    VFIOProxy *proxy;
     QLIST_HEAD(, VFIOGuestIOMMU) giommu_list;
     QLIST_HEAD(, VFIOHostDMAWindow) hostwin_list;
     QLIST_HEAD(, VFIOGroup) group_list;
@@ -214,6 +215,8 @@  VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp);
 void vfio_put_group(VFIOGroup *group);
 int vfio_get_device(VFIOGroup *group, const char *name,
                     VFIODevice *vbasedev, Error **errp);
+void vfio_connect_proxy(VFIOProxy *proxy, VFIOGroup *group, AddressSpace *as);
+void vfio_disconnect_proxy(VFIOGroup *group);
 
 extern const MemoryRegionOps vfio_region_ops;
 typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 8728d4d5c2..45acdeeb46 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -2206,6 +2206,41 @@  put_space_exit:
     return ret;
 }
 
+void vfio_connect_proxy(VFIOProxy *proxy, VFIOGroup *group, AddressSpace *as)
+{
+    VFIOAddressSpace *space;
+    VFIOContainer *container;
+
+    /*
+     * try to mirror vfio_connect_container()
+     * as much as possible
+     */
+
+    space = vfio_get_address_space(as);
+
+    container = g_malloc0(sizeof(*container));
+    container->space = space;
+    container->fd = -1;
+    QLIST_INIT(&container->hostwin_list);
+    container->proxy = proxy;
+
+    container->iommu_type = VFIO_TYPE1_IOMMU;
+    vfio_host_win_add(container, 0, (hwaddr)-1, 4096);
+    container->pgsizes = 4096;
+
+    QLIST_INIT(&container->group_list);
+    QLIST_INSERT_HEAD(&space->containers, container, next);
+
+    QLIST_INIT(&container->giommu_list);
+
+    group->container = container;
+    QLIST_INSERT_HEAD(&container->group_list, group, container_next);
+
+    container->listener = vfio_memory_listener;
+    memory_listener_register(&container->listener, container->space->as);
+    container->initialized = true;
+}
+
 static void vfio_disconnect_container(VFIOGroup *group)
 {
     VFIOContainer *container = group->container;
@@ -2248,6 +2283,41 @@  static void vfio_disconnect_container(VFIOGroup *group)
     }
 }
 
+void vfio_disconnect_proxy(VFIOGroup *group)
+{
+    VFIOContainer *container = group->container;
+    VFIOAddressSpace *space = container->space;
+    VFIOGuestIOMMU *giommu, *tmp;
+
+    /*
+     * try to mirror vfio_disconnect_container()
+     * as much as possible, knowing each device
+     * is in one group and one container
+     */
+
+    QLIST_REMOVE(group, container_next);
+    group->container = NULL;
+
+    /*
+     * Explicitly release the listener first before unset container,
+     * since unset may destroy the backend container if it's the last
+     * group.
+     */
+    memory_listener_unregister(&container->listener);
+
+    QLIST_REMOVE(container, next);
+
+    QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
+        memory_region_unregister_iommu_notifier(
+            MEMORY_REGION(giommu->iommu), &giommu->n);
+        QLIST_REMOVE(giommu, giommu_next);
+        g_free(giommu);
+    }
+
+    g_free(container);
+    vfio_put_address_space(space);
+}
+
 VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp)
 {
     VFIOGroup *group;
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 388b7d82d7..5ed42ad858 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -3358,6 +3358,7 @@  static void vfio_user_pci_realize(PCIDevice *pdev, Error **errp)
     VFIOPCIDevice *vdev = VFIO_PCI_BASE(pdev);
     VFIODevice *vbasedev = &vdev->vbasedev;
     VFIOProxy *proxy;
+    VFIOGroup *group = NULL;
     Error *err = NULL;
 
     if (!udev->sock_name) {
@@ -3385,6 +3386,19 @@  static void vfio_user_pci_realize(PCIDevice *pdev, Error **errp)
     vbasedev->no_mmap = false;
     vbasedev->ops = &vfio_user_pci_ops;
 
+    /*
+     * each device gets its own group and container
+     * make them unrelated to any host IOMMU groupings
+     */
+    group = g_malloc0(sizeof(*group));
+    group->fd = -1;
+    group->groupid = -1;
+    QLIST_INIT(&group->device_list);
+    QLIST_INSERT_HEAD(&group->device_list, vbasedev, next);
+    vbasedev->group = group;
+
+    vfio_connect_proxy(proxy, group, pci_device_iommu_address_space(pdev));
+
     return;
 
  error:
@@ -3395,6 +3409,11 @@  static void vfio_user_instance_finalize(Object *obj)
 {
     VFIOPCIDevice *vdev = VFIO_PCI_BASE(obj);
     VFIODevice *vbasedev = &vdev->vbasedev;
+    VFIOGroup *group = vbasedev->group;
+
+    vfio_disconnect_proxy(group);
+    g_free(group);
+    vbasedev->group = NULL;
 
     vfio_put_device(vdev);