aboutsummaryrefslogtreecommitdiffstats
path: root/Documentation/virt/kvm/devices/vfio.rst
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/virt/kvm/devices/vfio.rst')
-rw-r--r--Documentation/virt/kvm/devices/vfio.rst41
1 files changed, 41 insertions, 0 deletions
diff --git a/Documentation/virt/kvm/devices/vfio.rst b/Documentation/virt/kvm/devices/vfio.rst
new file mode 100644
index 000000000000..2d20dc561069
--- /dev/null
+++ b/Documentation/virt/kvm/devices/vfio.rst
@@ -0,0 +1,41 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===================
+VFIO virtual device
+===================
+
+Device types supported:
+
+ - KVM_DEV_TYPE_VFIO
+
+Only one VFIO instance may be created per VM. The created device
+tracks VFIO groups in use by the VM and features of those groups
+important to the correctness and acceleration of the VM. As groups
+are enabled and disabled for use by the VM, KVM should be updated
+about their presence. When registered with KVM, a reference to the
+VFIO-group is held by KVM.
+
+Groups:
+ KVM_DEV_VFIO_GROUP
+
+KVM_DEV_VFIO_GROUP attributes:
+ KVM_DEV_VFIO_GROUP_ADD: Add a VFIO group to VFIO-KVM device tracking
+ kvm_device_attr.addr points to an int32_t file descriptor
+ for the VFIO group.
+ KVM_DEV_VFIO_GROUP_DEL: Remove a VFIO group from VFIO-KVM device tracking
+ kvm_device_attr.addr points to an int32_t file descriptor
+ for the VFIO group.
+ KVM_DEV_VFIO_GROUP_SET_SPAPR_TCE: attaches a guest visible TCE table
+ allocated by sPAPR KVM.
+ kvm_device_attr.addr points to a struct::
+
+ struct kvm_vfio_spapr_tce {
+ __s32 groupfd;
+ __s32 tablefd;
+ };
+
+ where:
+
+ - @groupfd is a file descriptor for a VFIO group;
+ - @tablefd is a file descriptor for a TCE table allocated via
+ KVM_CREATE_SPAPR_TCE.