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: 46 * 47 * Allocate a vfio_ap_queue structure and associate it 48 * with the device as driver_data. 49 */ 50 static int vfio_ap_queue_dev_probe(struct ap_device *apdev) 51 { 52 struct vfio_ap_queue *q; 53 54 q = kzalloc(sizeof(*q), GFP_KERNEL); 55 if (!q) 56 return -ENOMEM; 57 dev_set_drvdata(&apdev->device, q); 58 q->apqn = to_ap_queue(&apdev->device)->qid; 59 q->saved_isc = VFIO_AP_ISC_INVALID; 60 return 0; 61 } 62 63 /** 64 * vfio_ap_queue_dev_remove: 65 * 66 * Takes the matrix lock to avoid actions on this device while removing 67 * Free the associated vfio_ap_queue structure 68 */ 69 static void vfio_ap_queue_dev_remove(struct ap_device *apdev) 70 { 71 struct vfio_ap_queue *q; 72 73 mutex_lock(&matrix_dev->lock); 74 q = dev_get_drvdata(&apdev->device); 75 vfio_ap_mdev_reset_queue(q, 1); 76 dev_set_drvdata(&apdev->device, NULL); 77 kfree(q); 78 mutex_unlock(&matrix_dev->lock); 79 } 80 81 static struct ap_driver vfio_ap_drv = { 82 .probe = vfio_ap_queue_dev_probe, 83 .remove = vfio_ap_queue_dev_remove, 84 .ids = ap_queue_ids, 85 }; 86 87 static void vfio_ap_matrix_dev_release(struct device *dev) 88 { 89 struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev); 90 91 kfree(matrix_dev); 92 } 93 94 static int matrix_bus_match(struct device *dev, struct device_driver *drv) 95 { 96 return 1; 97 } 98 99 static struct bus_type matrix_bus = { 100 .name = "matrix", 101 .match = &matrix_bus_match, 102 }; 103 104 static struct device_driver matrix_driver = { 105 .name = "vfio_ap", 106 .bus = &matrix_bus, 107 .suppress_bind_attrs = true, 108 }; 109 110 static int vfio_ap_matrix_dev_create(void) 111 { 112 int ret; 113 struct device *root_device; 114 115 root_device = root_device_register(VFIO_AP_ROOT_NAME); 116 if (IS_ERR(root_device)) 117 return PTR_ERR(root_device); 118 119 ret = bus_register(&matrix_bus); 120 if (ret) 121 goto bus_register_err; 122 123 matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL); 124 if (!matrix_dev) { 125 ret = -ENOMEM; 126 goto matrix_alloc_err; 127 } 128 129 /* Fill in config info via PQAP(QCI), if available */ 130 if (test_facility(12)) { 131 ret = ap_qci(&matrix_dev->info); 132 if (ret) 133 goto matrix_alloc_err; 134 } 135 136 mutex_init(&matrix_dev->lock); 137 INIT_LIST_HEAD(&matrix_dev->mdev_list); 138 139 dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME); 140 matrix_dev->device.parent = root_device; 141 matrix_dev->device.bus = &matrix_bus; 142 matrix_dev->device.release = vfio_ap_matrix_dev_release; 143 matrix_dev->vfio_ap_drv = &vfio_ap_drv; 144 145 ret = device_register(&matrix_dev->device); 146 if (ret) 147 goto matrix_reg_err; 148 149 ret = driver_register(&matrix_driver); 150 if (ret) 151 goto matrix_drv_err; 152 153 return 0; 154 155 matrix_drv_err: 156 device_unregister(&matrix_dev->device); 157 matrix_reg_err: 158 put_device(&matrix_dev->device); 159 matrix_alloc_err: 160 bus_unregister(&matrix_bus); 161 bus_register_err: 162 root_device_unregister(root_device); 163 return ret; 164 } 165 166 static void vfio_ap_matrix_dev_destroy(void) 167 { 168 struct device *root_device = matrix_dev->device.parent; 169 170 driver_unregister(&matrix_driver); 171 device_unregister(&matrix_dev->device); 172 bus_unregister(&matrix_bus); 173 root_device_unregister(root_device); 174 } 175 176 static int __init vfio_ap_init(void) 177 { 178 int ret; 179 180 /* If there are no AP instructions, there is nothing to pass through. */ 181 if (!ap_instructions_available()) 182 return -ENODEV; 183 184 ret = vfio_ap_matrix_dev_create(); 185 if (ret) 186 return ret; 187 188 ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); 189 if (ret) { 190 vfio_ap_matrix_dev_destroy(); 191 return ret; 192 } 193 194 ret = vfio_ap_mdev_register(); 195 if (ret) { 196 ap_driver_unregister(&vfio_ap_drv); 197 vfio_ap_matrix_dev_destroy(); 198 199 return ret; 200 } 201 202 return 0; 203 } 204 205 static void __exit vfio_ap_exit(void) 206 { 207 vfio_ap_mdev_unregister(); 208 ap_driver_unregister(&vfio_ap_drv); 209 vfio_ap_matrix_dev_destroy(); 210 } 211 212 module_init(vfio_ap_init); 213 module_exit(vfio_ap_exit); 214