summaryrefslogtreecommitdiffstats
path: root/Documentation/virtual/kvm/devices/vfio.txt
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/virtual/kvm/devices/vfio.txt')
-rw-r--r--Documentation/virtual/kvm/devices/vfio.txt36
1 files changed, 36 insertions, 0 deletions
diff --git a/Documentation/virtual/kvm/devices/vfio.txt b/Documentation/virtual/kvm/devices/vfio.txt
new file mode 100644
index 000000000..528c77c80
--- /dev/null
+++ b/Documentation/virtual/kvm/devices/vfio.txt
@@ -0,0 +1,36 @@
+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.