drivers/s390/crypto/vfio_ap_drv.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * VFIO based AP device driver
   4  *
   5  * Copyright IBM Corp. 2018
   6  *
   7  * Author(s): Tony Krowiak <akrowiak@linux.ibm.com>
   8  *            Pierre Morel <pmorel@linux.ibm.com>
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/mod_devicetable.h>
  13 #include <linux/slab.h>
  14 #include <linux/string.h>
  15 #include <asm/facility.h>
  16 #include "vfio_ap_private.h"
  17 #include "vfio_ap_debug.h"
  18
  19 #define VFIO_AP_ROOT_NAME "vfio_ap"
  20 #define VFIO_AP_DEV_NAME "matrix"
  21
  22 MODULE_AUTHOR("IBM Corporation");
  23 MODULE_DESCRIPTION("VFIO AP device driver, Copyright IBM Corp. 2018");
  24 MODULE_LICENSE("GPL v2");
  25
  26 struct ap_matrix_dev *matrix_dev;
  27 debug_info_t *vfio_ap_dbf_info;
  28
  29 static ssize_t features_show(struct device *dev, struct device_attribute *attr, char *buf)
  30 {
  31         return sysfs_emit(buf, "guest_matrix hotplug ap_config\n");
  32 }
  33 static DEVICE_ATTR_RO(features);
  34
  35 static struct attribute *matrix_dev_attrs[] = {
  36         &dev_attr_features.attr,
  37         NULL,
  38 };
  39 ATTRIBUTE_GROUPS(matrix_dev);
  40
  41 /* Only type 10 adapters (CEX4 and later) are supported
  42  * by the AP matrix device driver
  43  */
  44 static struct ap_device_id ap_queue_ids[] = {
  45         { .dev_type = AP_DEVICE_TYPE_CEX4,
  46           .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
  47         { .dev_type = AP_DEVICE_TYPE_CEX5,
  48           .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
  49         { .dev_type = AP_DEVICE_TYPE_CEX6,
  50           .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
  51         { .dev_type = AP_DEVICE_TYPE_CEX7,
  52           .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
  53         { .dev_type = AP_DEVICE_TYPE_CEX8,
  54           .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
  55         { /* end of sibling */ },
  56 };
  57
  58 static struct ap_driver vfio_ap_drv = {
  59         .probe = vfio_ap_mdev_probe_queue,
  60         .remove = vfio_ap_mdev_remove_queue,
  61         .in_use = vfio_ap_mdev_resource_in_use,
  62         .on_config_changed = vfio_ap_on_cfg_changed,
  63         .on_scan_complete = vfio_ap_on_scan_complete,
  64         .ids = ap_queue_ids,
  65 };
  66
  67 static void vfio_ap_matrix_dev_release(struct device *dev)
  68 {
  69         struct ap_matrix_dev *matrix_dev;
  70
  71         matrix_dev = container_of(dev, struct ap_matrix_dev, device);
  72         kfree(matrix_dev);
  73 }
  74
  75 static const struct bus_type matrix_bus = {
  76         .name = "matrix",
  77 };
  78
  79 static struct device_driver matrix_driver = {
  80         .name = "vfio_ap",
  81         .bus = &matrix_bus,
  82         .suppress_bind_attrs = true,
  83         .dev_groups = matrix_dev_groups,
  84 };
  85
  86 static int vfio_ap_matrix_dev_create(void)
  87 {
  88         int ret;
  89         struct device *root_device;
  90
  91         root_device = root_device_register(VFIO_AP_ROOT_NAME);
  92         if (IS_ERR(root_device))
  93                 return PTR_ERR(root_device);
  94
  95         ret = bus_register(&matrix_bus);
  96         if (ret)
  97                 goto bus_register_err;
  98
  99         matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
 100         if (!matrix_dev) {
 101                 ret = -ENOMEM;
 102                 goto matrix_alloc_err;
 103         }
 104
 105         /* Fill in config info via PQAP(QCI), if available */
 106         if (test_facility(12)) {
 107                 ret = ap_qci(&matrix_dev->info);
 108                 if (ret)
 109                         goto matrix_alloc_err;
 110         }
 111
 112         mutex_init(&matrix_dev->mdevs_lock);
 113         INIT_LIST_HEAD(&matrix_dev->mdev_list);
 114         mutex_init(&matrix_dev->guests_lock);
 115
 116         dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME);
 117         matrix_dev->device.parent = root_device;
 118         matrix_dev->device.bus = &matrix_bus;
 119         matrix_dev->device.release = vfio_ap_matrix_dev_release;
 120         matrix_dev->vfio_ap_drv = &vfio_ap_drv;
 121
 122         ret = device_register(&matrix_dev->device);
 123         if (ret)
 124                 goto matrix_reg_err;
 125
 126         ret = driver_register(&matrix_driver);
 127         if (ret)
 128                 goto matrix_drv_err;
 129
 130         return 0;
 131
 132 matrix_drv_err:
 133         device_del(&matrix_dev->device);
 134 matrix_reg_err:
 135         put_device(&matrix_dev->device);
 136 matrix_alloc_err:
 137         bus_unregister(&matrix_bus);
 138 bus_register_err:
 139         root_device_unregister(root_device);
 140         return ret;
 141 }
 142
 143 static void vfio_ap_matrix_dev_destroy(void)
 144 {
 145         struct device *root_device = matrix_dev->device.parent;
 146
 147         driver_unregister(&matrix_driver);
 148         device_unregister(&matrix_dev->device);
 149         bus_unregister(&matrix_bus);
 150         root_device_unregister(root_device);
 151 }
 152
 153 static int __init vfio_ap_dbf_info_init(void)
 154 {
 155         vfio_ap_dbf_info = debug_register("vfio_ap", 1, 1,
 156                                           DBF_MAX_SPRINTF_ARGS * sizeof(long));
 157
 158         if (!vfio_ap_dbf_info)
 159                 return -ENOENT;
 160
 161         debug_register_view(vfio_ap_dbf_info, &debug_sprintf_view);
 162         debug_set_level(vfio_ap_dbf_info, DBF_WARN);
 163
 164         return 0;
 165 }
 166
 167 static int __init vfio_ap_init(void)
 168 {
 169         int ret;
 170
 171         ret = vfio_ap_dbf_info_init();
 172         if (ret)
 173                 return ret;
 174
 175         /* If there are no AP instructions, there is nothing to pass through. */
 176         if (!ap_instructions_available())
 177                 return -ENODEV;
 178
 179         ret = vfio_ap_matrix_dev_create();
 180         if (ret)
 181                 return ret;
 182
 183         ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME);
 184         if (ret) {
 185                 vfio_ap_matrix_dev_destroy();
 186                 return ret;
 187         }
 188
 189         ret = vfio_ap_mdev_register();
 190         if (ret) {
 191                 ap_driver_unregister(&vfio_ap_drv);
 192                 vfio_ap_matrix_dev_destroy();
 193
 194                 return ret;
 195         }
 196
 197         return 0;
 198 }
 199
 200 static void __exit vfio_ap_exit(void)
 201 {
 202         vfio_ap_mdev_unregister();
 203         ap_driver_unregister(&vfio_ap_drv);
 204         vfio_ap_matrix_dev_destroy();
 205         debug_unregister(vfio_ap_dbf_info);
 206 }
 207
 208 module_init(vfio_ap_init);
 209 module_exit(vfio_ap_exit);