On Tue, Nov 12, 2019 at 10:28:26PM +0100, Greg KH wrote:
> > + */
> > +struct virtbus_device {
> > + const char *name;
> > + int id;
> > + const struct virtbus_dev_id *dev_id;
> > + struct device dev;
> > + void *data;
> > +};
> > +
> > +struct virtbus_driver {
> > + int (*probe)(struct virtbus_device *);
> > + int (*remove)(struct virtbus_device *);
> > + void (*shutdown)(struct virtbus_device *);
> > + int (*suspend)(struct virtbus_device *, pm_message_t state);
> > + int (*resume)(struct virtbus_device *);
> > + struct device_driver driver;
> > + const struct virtbus_dev_id *id_table;
> > +};
> > +
> > +#define virtbus_get_dev_id(vdev) ((vdev)->id_entry)
> > +#define virtbus_get_devdata(dev) ((dev)->devdata)
>
> What are these for?
As far as I can see, the scheme here, using the language from the most
recent discussion is:
// in core or netdev module
int mlx5_core_create()
{
struct mlx5_core_dev *core = kzalloc(..)
[..]
core->vdev = virtbus_dev_alloc("mlx5_core", core);
}
// in rdma module
static int mlx5_rdma_probe(struct virtbus_device *dev)
{
// Get the value passed to virtbus_dev_alloc()
struct mlx5_core_dev *core = virtbus_get_devdata(dev)
// Use the huge API surrounding struct mlx5_core_dev
qp = mlx5_core_create_qp(core, ...);
}
static struct virtbus_driver mlx5_rdma_driver = {
.probe = mlx5_rdma_probe,
.match = {"mlx5_core"}
}
Drivers that match "mlx5_core" know that the opaque
'virtbus_get_devdata()' is a 'struct mlx5_core_dev *' and use that
access the core driver.
A "ice_core" would know it is some 'struct ice_core_dev *' for Intel
and uses that pointer, etc.
ie it is just a way to a pass a 'void *' from one module to another
while using the driver core to manage module autoloading and binding.
Jason
