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 18 #define VFIO_AP_ROOT_NAME "vfio_ap" 19 #define VFIO_AP_DEV_NAME "matrix" 20 21 MODULE_AUTHOR("IBM Corporation"); 22 MODULE_DESCRIPTION("VFIO AP device driver, Copyright IBM Corp. 2018"); 23 MODULE_LICENSE("GPL v2"); 24 25 struct ap_matrix_dev *matrix_dev; 26 27 /* Only type 10 adapters (CEX4 and later) are supported 28 * by the AP matrix device driver 29 */ 30 static struct ap_device_id ap_queue_ids[] = { 31 { .dev_type = AP_DEVICE_TYPE_CEX4, 32 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 33 { .dev_type = AP_DEVICE_TYPE_CEX5, 34 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 35 { .dev_type = AP_DEVICE_TYPE_CEX6, 36 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 37 { .dev_type = AP_DEVICE_TYPE_CEX7, 38 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 39 { /* end of sibling */ }, 40 }; 41 42 MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids); 43 44 /** 45 * vfio_ap_queue_dev_probe: Allocate a vfio_ap_queue structure and associate it 46 * with the device as driver_data. 47 * 48 * @apdev: the AP device being probed 49 * 50 * Return: returns 0 if the probe succeeded; otherwise, returns -ENOMEM if 51 * storage could not be allocated for a vfio_ap_queue object. 52 */ 53 static int vfio_ap_queue_dev_probe(struct ap_device *apdev) 54 { 55 struct vfio_ap_queue *q; 56 57 q = kzalloc(sizeof(*q), GFP_KERNEL); 58 if (!q) 59 return -ENOMEM; 60 dev_set_drvdata(&apdev->device, q); 61 q->apqn = to_ap_queue(&apdev->device)->qid; 62 q->saved_isc = VFIO_AP_ISC_INVALID; 63 return 0; 64 } 65 66 /** 67 * vfio_ap_queue_dev_remove: Free the associated vfio_ap_queue structure. 68 * 69 * @apdev: the AP device being removed 70 * 71 * Takes the matrix lock to avoid actions on this device while doing the remove. 72 */ 73 static void vfio_ap_queue_dev_remove(struct ap_device *apdev) 74 { 75 struct vfio_ap_queue *q; 76 77 mutex_lock(&matrix_dev->lock); 78 q = dev_get_drvdata(&apdev->device); 79 vfio_ap_mdev_reset_queue(q, 1); 80 dev_set_drvdata(&apdev->device, NULL); 81 kfree(q); 82 mutex_unlock(&matrix_dev->lock); 83 } 84 85 static struct ap_driver vfio_ap_drv = { 86 .probe = vfio_ap_queue_dev_probe, 87 .remove = vfio_ap_queue_dev_remove, 88 .ids = ap_queue_ids, 89 }; 90 91 static void vfio_ap_matrix_dev_release(struct device *dev) 92 { 93 struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev); 94 95 kfree(matrix_dev); 96 } 97 98 static int matrix_bus_match(struct device *dev, struct device_driver *drv) 99 { 100 return 1; 101 } 102 103 static struct bus_type matrix_bus = { 104 .name = "matrix", 105 .match = &matrix_bus_match, 106 }; 107 108 static struct device_driver matrix_driver = { 109 .name = "vfio_ap", 110 .bus = &matrix_bus, 111 .suppress_bind_attrs = true, 112 }; 113 114 static int vfio_ap_matrix_dev_create(void) 115 { 116 int ret; 117 struct device *root_device; 118 119 root_device = root_device_register(VFIO_AP_ROOT_NAME); 120 if (IS_ERR(root_device)) 121 return PTR_ERR(root_device); 122 123 ret = bus_register(&matrix_bus); 124 if (ret) 125 goto bus_register_err; 126 127 matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL); 128 if (!matrix_dev) { 129 ret = -ENOMEM; 130 goto matrix_alloc_err; 131 } 132 133 /* Fill in config info via PQAP(QCI), if available */ 134 if (test_facility(12)) { 135 ret = ap_qci(&matrix_dev->info); 136 if (ret) 137 goto matrix_alloc_err; 138 } 139 140 mutex_init(&matrix_dev->lock); 141 INIT_LIST_HEAD(&matrix_dev->mdev_list); 142 143 dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME); 144 matrix_dev->device.parent = root_device; 145 matrix_dev->device.bus = &matrix_bus; 146 matrix_dev->device.release = vfio_ap_matrix_dev_release; 147 matrix_dev->vfio_ap_drv = &vfio_ap_drv; 148 149 ret = device_register(&matrix_dev->device); 150 if (ret) 151 goto matrix_reg_err; 152 153 ret = driver_register(&matrix_driver); 154 if (ret) 155 goto matrix_drv_err; 156 157 return 0; 158 159 matrix_drv_err: 160 device_unregister(&matrix_dev->device); 161 matrix_reg_err: 162 put_device(&matrix_dev->device); 163 matrix_alloc_err: 164 bus_unregister(&matrix_bus); 165 bus_register_err: 166 root_device_unregister(root_device); 167 return ret; 168 } 169 170 static void vfio_ap_matrix_dev_destroy(void) 171 { 172 struct device *root_device = matrix_dev->device.parent; 173 174 driver_unregister(&matrix_driver); 175 device_unregister(&matrix_dev->device); 176 bus_unregister(&matrix_bus); 177 root_device_unregister(root_device); 178 } 179 180 static int __init vfio_ap_init(void) 181 { 182 int ret; 183 184 /* If there are no AP instructions, there is nothing to pass through. */ 185 if (!ap_instructions_available()) 186 return -ENODEV; 187 188 ret = vfio_ap_matrix_dev_create(); 189 if (ret) 190 return ret; 191 192 ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); 193 if (ret) { 194 vfio_ap_matrix_dev_destroy(); 195 return ret; 196 } 197 198 ret = vfio_ap_mdev_register(); 199 if (ret) { 200 ap_driver_unregister(&vfio_ap_drv); 201 vfio_ap_matrix_dev_destroy(); 202 203 return ret; 204 } 205 206 return 0; 207 } 208 209 static void __exit vfio_ap_exit(void) 210 { 211 vfio_ap_mdev_unregister(); 212 ap_driver_unregister(&vfio_ap_drv); 213 vfio_ap_matrix_dev_destroy(); 214 } 215 216 module_init(vfio_ap_init); 217 module_exit(vfio_ap_exit); 218