VFIO: platform: populate the reset function on probe

The reset function lookup happens on vfio-platform probe. The reset
module load is requested  and a reference to the function symbol is
hold. The reference is released on vfio-platform remove.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Acked-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Tested-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Eric Auger 2015-06-15 11:09:44 +02:00 committed by Alex Williamson
parent 813ae66008
commit 3eeb0d510c

View file

@ -28,6 +28,36 @@ static DEFINE_MUTEX(driver_lock);
static const struct vfio_platform_reset_combo reset_lookup_table[] = {
};
static void vfio_platform_get_reset(struct vfio_platform_device *vdev,
struct device *dev)
{
const char *compat;
int (*reset)(struct vfio_platform_device *);
int ret, i;
ret = device_property_read_string(dev, "compatible", &compat);
if (ret)
return;
for (i = 0 ; i < ARRAY_SIZE(reset_lookup_table); i++) {
if (!strcmp(reset_lookup_table[i].compat, compat)) {
request_module(reset_lookup_table[i].module_name);
reset = __symbol_get(
reset_lookup_table[i].reset_function_name);
if (reset) {
vdev->reset = reset;
return;
}
}
}
}
static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
{
if (vdev->reset)
symbol_put_addr(vdev->reset);
}
static int vfio_platform_regions_init(struct vfio_platform_device *vdev)
{
int cnt = 0, i;
@ -516,6 +546,8 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
return ret;
}
vfio_platform_get_reset(vdev, dev);
mutex_init(&vdev->igate);
return 0;
@ -527,8 +559,11 @@ struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
struct vfio_platform_device *vdev;
vdev = vfio_del_group_dev(dev);
if (vdev)
if (vdev) {
vfio_platform_put_reset(vdev);
iommu_group_put(dev->iommu_group);
}
return vdev;
}