vfio/{iommufd, container}: Invoke HostIOMMUDevice::realize() during attach_device()
Move the HostIOMMUDevice::realize() to be invoked during the attach of the device
before we allocate IOMMUFD hardware pagetable objects (HWPT). This allows the use
of the hw_caps obtained by IOMMU_GET_HW_INFO that essentially tell if the IOMMU
behind the device supports dirty tracking.
Note: The HostIOMMUDevice data from legacy backend is static and doesn't
need any information from the (type1-iommu) backend to be initialized.
In contrast however, the IOMMUFD HostIOMMUDevice data requires the
iommufd FD to be connected and having a devid to be able to successfully
GET_HW_INFO. This means vfio_device_hiod_realize() is called in
different places within the backend .attach_device() implementation.
Suggested-by: Cédric Le Goater <clg@redhat.cm>
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Cédric Le Goater <clg@redhat.com>
[ clg: Fixed error handling in iommufd_cdev_attach() ]
Signed-off-by: Cédric Le Goater <clg@redhat.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index d7f02be..26e74fa 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1536,7 +1536,7 @@
{
const VFIOIOMMUClass *ops =
VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_LEGACY));
- HostIOMMUDevice *hiod;
+ HostIOMMUDevice *hiod = NULL;
if (vbasedev->iommufd) {
ops = VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_IOMMUFD));
@@ -1544,21 +1544,17 @@
assert(ops);
+
+ if (!vbasedev->mdev) {
+ hiod = HOST_IOMMU_DEVICE(object_new(ops->hiod_typename));
+ vbasedev->hiod = hiod;
+ }
+
if (!ops->attach_device(name, vbasedev, as, errp)) {
- return false;
- }
-
- if (vbasedev->mdev) {
- return true;
- }
-
- hiod = HOST_IOMMU_DEVICE(object_new(ops->hiod_typename));
- if (!HOST_IOMMU_DEVICE_GET_CLASS(hiod)->realize(hiod, vbasedev, errp)) {
object_unref(hiod);
- ops->detach_device(vbasedev);
+ vbasedev->hiod = NULL;
return false;
}
- vbasedev->hiod = hiod;
return true;
}
diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index 10cb4b4..9ccdb63 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -914,6 +914,10 @@
trace_vfio_attach_device(vbasedev->name, groupid);
+ if (!vfio_device_hiod_realize(vbasedev, errp)) {
+ return false;
+ }
+
group = vfio_get_group(groupid, as, errp);
if (!group) {
return false;
diff --git a/hw/vfio/helpers.c b/hw/vfio/helpers.c
index 7e23e90..ea15c79 100644
--- a/hw/vfio/helpers.c
+++ b/hw/vfio/helpers.c
@@ -689,3 +689,14 @@
subsys = realpath(tmp, NULL);
return subsys && (strcmp(subsys, "/sys/bus/mdev") == 0);
}
+
+bool vfio_device_hiod_realize(VFIODevice *vbasedev, Error **errp)
+{
+ HostIOMMUDevice *hiod = vbasedev->hiod;
+
+ if (!hiod) {
+ return true;
+ }
+
+ return HOST_IOMMU_DEVICE_GET_CLASS(hiod)->realize(hiod, vbasedev, errp);
+}
diff --git a/hw/vfio/iommufd.c b/hw/vfio/iommufd.c
index fb87e64..798c479 100644
--- a/hw/vfio/iommufd.c
+++ b/hw/vfio/iommufd.c
@@ -404,6 +404,17 @@
space = vfio_get_address_space(as);
+ /*
+ * The HostIOMMUDevice data from legacy backend is static and doesn't need
+ * any information from the (type1-iommu) backend to be initialized. In
+ * contrast however, the IOMMUFD HostIOMMUDevice data requires the iommufd
+ * FD to be connected and having a devid to be able to successfully call
+ * iommufd_backend_get_device_info().
+ */
+ if (!vfio_device_hiod_realize(vbasedev, errp)) {
+ goto err_alloc_ioas;
+ }
+
/* try to attach to an existing container in this space */
QLIST_FOREACH(bcontainer, &space->containers, next) {
container = container_of(bcontainer, VFIOIOMMUFDContainer, bcontainer);
diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
index 1a96678..4e44b26 100644
--- a/include/hw/vfio/vfio-common.h
+++ b/include/hw/vfio/vfio-common.h
@@ -242,6 +242,7 @@
void vfio_reset_handler(void *opaque);
struct vfio_device_info *vfio_get_device_info(int fd);
bool vfio_device_is_mdev(VFIODevice *vbasedev);
+bool vfio_device_hiod_realize(VFIODevice *vbasedev, Error **errp);
bool vfio_attach_device(char *name, VFIODevice *vbasedev,
AddressSpace *as, Error **errp);
void vfio_detach_device(VFIODevice *vbasedev);
