vfio: Split creation of a vfio_device into init and register ops

[linux-2.6-microblaze.git] / Documentation / driver-api / vfio.rst

diff --git a/Documentation/driver-api/vfio.rst b/Documentation/driver-api/vfio.rst
index f1a4d3c..d3a0230 100644 (file)
--- a/Documentation/driver-api/vfio.rst
+++ b/Documentation/driver-api/vfio.rst
@@ -249,18 +249,23 @@ VFIO bus driver API
 
 VFIO bus drivers, such as vfio-pci make use of only a few interfaces
 into VFIO core.  When devices are bound and unbound to the driver,
-the driver should call vfio_add_group_dev() and vfio_del_group_dev()
-respectively::
-
-       extern int vfio_add_group_dev(struct device *dev,
-                                     const struct vfio_device_ops *ops,
-                                     void *device_data);
-
-       extern void *vfio_del_group_dev(struct device *dev);
-
-vfio_add_group_dev() indicates to the core to begin tracking the
-iommu_group of the specified dev and register the dev as owned by
-a VFIO bus driver.  The driver provides an ops structure for callbacks
+the driver should call vfio_register_group_dev() and
+vfio_unregister_group_dev() respectively::
+
+       void vfio_init_group_dev(struct vfio_device *device,
+                               struct device *dev,
+                               const struct vfio_device_ops *ops,
+                               void *device_data);
+       int vfio_register_group_dev(struct vfio_device *device);
+       void vfio_unregister_group_dev(struct vfio_device *device);
+
+The driver should embed the vfio_device in its own structure and call
+vfio_init_group_dev() to pre-configure it before going to registration.
+vfio_register_group_dev() indicates to the core to begin tracking the
+iommu_group of the specified dev and register the dev as owned by a VFIO bus
+driver. Once vfio_register_group_dev() returns it is possible for userspace to
+start accessing the driver, thus the driver should ensure it is completely
+ready before calling it. The driver provides an ops structure for callbacks
 similar to a file operations structure::
 
        struct vfio_device_ops {
@@ -276,7 +281,7 @@ similar to a file operations structure::
        };
 
 Each function is passed the device_data that was originally registered
-in the vfio_add_group_dev() call above.  This allows the bus driver
+in the vfio_register_group_dev() call above.  This allows the bus driver
 an easy place to store its opaque, private data.  The open/release
 callbacks are issued when a new file descriptor is created for a
 device (via VFIO_GROUP_GET_DEVICE_FD).  The ioctl interface provides