swh:1:snp:173f8deb0c56c557784b4fd217e7608ac6197844
Tip revision: 0477e92881850d44910a7e94fc2c46f96faa131f authored by Linus Torvalds on 06 December 2020, 22:25:12 UTC
Linux 5.10-rc7
Linux 5.10-rc7
Tip revision: 0477e92
vfio_ap_drv.c
// SPDX-License-Identifier: GPL-2.0+
/*
* VFIO based AP device driver
*
* Copyright IBM Corp. 2018
*
* Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
* Pierre Morel <pmorel@linux.ibm.com>
*/
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <asm/facility.h>
#include "vfio_ap_private.h"
#define VFIO_AP_ROOT_NAME "vfio_ap"
#define VFIO_AP_DEV_NAME "matrix"
MODULE_AUTHOR("IBM Corporation");
MODULE_DESCRIPTION("VFIO AP device driver, Copyright IBM Corp. 2018");
MODULE_LICENSE("GPL v2");
static struct ap_driver vfio_ap_drv;
struct ap_matrix_dev *matrix_dev;
/* Only type 10 adapters (CEX4 and later) are supported
* by the AP matrix device driver
*/
static struct ap_device_id ap_queue_ids[] = {
{ .dev_type = AP_DEVICE_TYPE_CEX4,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX5,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX6,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ .dev_type = AP_DEVICE_TYPE_CEX7,
.match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
{ /* end of sibling */ },
};
MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids);
/**
* vfio_ap_queue_dev_probe:
*
* Allocate a vfio_ap_queue structure and associate it
* with the device as driver_data.
*/
static int vfio_ap_queue_dev_probe(struct ap_device *apdev)
{
struct vfio_ap_queue *q;
q = kzalloc(sizeof(*q), GFP_KERNEL);
if (!q)
return -ENOMEM;
dev_set_drvdata(&apdev->device, q);
q->apqn = to_ap_queue(&apdev->device)->qid;
q->saved_isc = VFIO_AP_ISC_INVALID;
return 0;
}
/**
* vfio_ap_queue_dev_remove:
*
* Takes the matrix lock to avoid actions on this device while removing
* Free the associated vfio_ap_queue structure
*/
static void vfio_ap_queue_dev_remove(struct ap_device *apdev)
{
struct vfio_ap_queue *q;
int apid, apqi;
mutex_lock(&matrix_dev->lock);
q = dev_get_drvdata(&apdev->device);
dev_set_drvdata(&apdev->device, NULL);
apid = AP_QID_CARD(q->apqn);
apqi = AP_QID_QUEUE(q->apqn);
vfio_ap_mdev_reset_queue(apid, apqi, 1);
vfio_ap_irq_disable(q);
kfree(q);
mutex_unlock(&matrix_dev->lock);
}
static void vfio_ap_matrix_dev_release(struct device *dev)
{
struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev);
kfree(matrix_dev);
}
static int matrix_bus_match(struct device *dev, struct device_driver *drv)
{
return 1;
}
static struct bus_type matrix_bus = {
.name = "matrix",
.match = &matrix_bus_match,
};
static struct device_driver matrix_driver = {
.name = "vfio_ap",
.bus = &matrix_bus,
.suppress_bind_attrs = true,
};
static int vfio_ap_matrix_dev_create(void)
{
int ret;
struct device *root_device;
root_device = root_device_register(VFIO_AP_ROOT_NAME);
if (IS_ERR(root_device))
return PTR_ERR(root_device);
ret = bus_register(&matrix_bus);
if (ret)
goto bus_register_err;
matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
if (!matrix_dev) {
ret = -ENOMEM;
goto matrix_alloc_err;
}
/* Fill in config info via PQAP(QCI), if available */
if (test_facility(12)) {
ret = ap_qci(&matrix_dev->info);
if (ret)
goto matrix_alloc_err;
}
mutex_init(&matrix_dev->lock);
INIT_LIST_HEAD(&matrix_dev->mdev_list);
dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME);
matrix_dev->device.parent = root_device;
matrix_dev->device.bus = &matrix_bus;
matrix_dev->device.release = vfio_ap_matrix_dev_release;
matrix_dev->vfio_ap_drv = &vfio_ap_drv;
ret = device_register(&matrix_dev->device);
if (ret)
goto matrix_reg_err;
ret = driver_register(&matrix_driver);
if (ret)
goto matrix_drv_err;
return 0;
matrix_drv_err:
device_unregister(&matrix_dev->device);
matrix_reg_err:
put_device(&matrix_dev->device);
matrix_alloc_err:
bus_unregister(&matrix_bus);
bus_register_err:
root_device_unregister(root_device);
return ret;
}
static void vfio_ap_matrix_dev_destroy(void)
{
struct device *root_device = matrix_dev->device.parent;
driver_unregister(&matrix_driver);
device_unregister(&matrix_dev->device);
bus_unregister(&matrix_bus);
root_device_unregister(root_device);
}
static int __init vfio_ap_init(void)
{
int ret;
/* If there are no AP instructions, there is nothing to pass through. */
if (!ap_instructions_available())
return -ENODEV;
ret = vfio_ap_matrix_dev_create();
if (ret)
return ret;
memset(&vfio_ap_drv, 0, sizeof(vfio_ap_drv));
vfio_ap_drv.probe = vfio_ap_queue_dev_probe;
vfio_ap_drv.remove = vfio_ap_queue_dev_remove;
vfio_ap_drv.ids = ap_queue_ids;
ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME);
if (ret) {
vfio_ap_matrix_dev_destroy();
return ret;
}
ret = vfio_ap_mdev_register();
if (ret) {
ap_driver_unregister(&vfio_ap_drv);
vfio_ap_matrix_dev_destroy();
return ret;
}
return 0;
}
static void __exit vfio_ap_exit(void)
{
vfio_ap_mdev_unregister();
ap_driver_unregister(&vfio_ap_drv);
vfio_ap_matrix_dev_destroy();
}
module_init(vfio_ap_init);
module_exit(vfio_ap_exit);