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 static struct ap_driver vfio_ap_drv; 26 27 struct ap_matrix_dev *matrix_dev; 28 29 /* Only type 10 adapters (CEX4 and later) are supported 30 * by the AP matrix device driver 31 */ 32 static struct ap_device_id ap_queue_ids[] = { 33 { .dev_type = AP_DEVICE_TYPE_CEX4, 34 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 35 { .dev_type = AP_DEVICE_TYPE_CEX5, 36 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 37 { .dev_type = AP_DEVICE_TYPE_CEX6, 38 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 39 { .dev_type = AP_DEVICE_TYPE_CEX7, 40 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 41 { /* end of sibling */ }, 42 }; 43 44 MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids); 45 46 /** 47 * vfio_ap_queue_dev_probe: 48 * 49 * Allocate a vfio_ap_queue structure and associate it 50 * with the device as driver_data. 51 */ 52 static int vfio_ap_queue_dev_probe(struct ap_device *apdev) 53 { 54 struct vfio_ap_queue *q; 55 56 q = kzalloc(sizeof(*q), GFP_KERNEL); 57 if (!q) 58 return -ENOMEM; 59 dev_set_drvdata(&apdev->device, q); 60 q->apqn = to_ap_queue(&apdev->device)->qid; 61 q->saved_isc = VFIO_AP_ISC_INVALID; 62 return 0; 63 } 64 65 /** 66 * vfio_ap_queue_dev_remove: 67 * 68 * Takes the matrix lock to avoid actions on this device while removing 69 * Free the associated vfio_ap_queue structure 70 */ 71 static void vfio_ap_queue_dev_remove(struct ap_device *apdev) 72 { 73 struct vfio_ap_queue *q; 74 75 mutex_lock(&matrix_dev->lock); 76 q = dev_get_drvdata(&apdev->device); 77 vfio_ap_mdev_reset_queue(q, 1); 78 dev_set_drvdata(&apdev->device, NULL); 79 kfree(q); 80 mutex_unlock(&matrix_dev->lock); 81 } 82 83 static void vfio_ap_matrix_dev_release(struct device *dev) 84 { 85 struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev); 86 87 kfree(matrix_dev); 88 } 89 90 static int matrix_bus_match(struct device *dev, struct device_driver *drv) 91 { 92 return 1; 93 } 94 95 static struct bus_type matrix_bus = { 96 .name = "matrix", 97 .match = &matrix_bus_match, 98 }; 99 100 static struct device_driver matrix_driver = { 101 .name = "vfio_ap", 102 .bus = &matrix_bus, 103 .suppress_bind_attrs = true, 104 }; 105 106 static int vfio_ap_matrix_dev_create(void) 107 { 108 int ret; 109 struct device *root_device; 110 111 root_device = root_device_register(VFIO_AP_ROOT_NAME); 112 if (IS_ERR(root_device)) 113 return PTR_ERR(root_device); 114 115 ret = bus_register(&matrix_bus); 116 if (ret) 117 goto bus_register_err; 118 119 matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL); 120 if (!matrix_dev) { 121 ret = -ENOMEM; 122 goto matrix_alloc_err; 123 } 124 125 /* Fill in config info via PQAP(QCI), if available */ 126 if (test_facility(12)) { 127 ret = ap_qci(&matrix_dev->info); 128 if (ret) 129 goto matrix_alloc_err; 130 } 131 132 mutex_init(&matrix_dev->lock); 133 INIT_LIST_HEAD(&matrix_dev->mdev_list); 134 135 dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME); 136 matrix_dev->device.parent = root_device; 137 matrix_dev->device.bus = &matrix_bus; 138 matrix_dev->device.release = vfio_ap_matrix_dev_release; 139 matrix_dev->vfio_ap_drv = &vfio_ap_drv; 140 141 ret = device_register(&matrix_dev->device); 142 if (ret) 143 goto matrix_reg_err; 144 145 ret = driver_register(&matrix_driver); 146 if (ret) 147 goto matrix_drv_err; 148 149 return 0; 150 151 matrix_drv_err: 152 device_unregister(&matrix_dev->device); 153 matrix_reg_err: 154 put_device(&matrix_dev->device); 155 matrix_alloc_err: 156 bus_unregister(&matrix_bus); 157 bus_register_err: 158 root_device_unregister(root_device); 159 return ret; 160 } 161 162 static void vfio_ap_matrix_dev_destroy(void) 163 { 164 struct device *root_device = matrix_dev->device.parent; 165 166 driver_unregister(&matrix_driver); 167 device_unregister(&matrix_dev->device); 168 bus_unregister(&matrix_bus); 169 root_device_unregister(root_device); 170 } 171 172 static int __init vfio_ap_init(void) 173 { 174 int ret; 175 176 /* If there are no AP instructions, there is nothing to pass through. */ 177 if (!ap_instructions_available()) 178 return -ENODEV; 179 180 ret = vfio_ap_matrix_dev_create(); 181 if (ret) 182 return ret; 183 184 memset(&vfio_ap_drv, 0, sizeof(vfio_ap_drv)); 185 vfio_ap_drv.probe = vfio_ap_queue_dev_probe; 186 vfio_ap_drv.remove = vfio_ap_queue_dev_remove; 187 vfio_ap_drv.ids = ap_queue_ids; 188 189 ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); 190 if (ret) { 191 vfio_ap_matrix_dev_destroy(); 192 return ret; 193 } 194 195 ret = vfio_ap_mdev_register(); 196 if (ret) { 197 ap_driver_unregister(&vfio_ap_drv); 198 vfio_ap_matrix_dev_destroy(); 199 200 return ret; 201 } 202 203 return 0; 204 } 205 206 static void __exit vfio_ap_exit(void) 207 { 208 vfio_ap_mdev_unregister(); 209 ap_driver_unregister(&vfio_ap_drv); 210 vfio_ap_matrix_dev_destroy(); 211 } 212 213 module_init(vfio_ap_init); 214 module_exit(vfio_ap_exit); 215