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 int apid, apqi; 75 76 mutex_lock(&matrix_dev->lock); 77 q = dev_get_drvdata(&apdev->device); 78 dev_set_drvdata(&apdev->device, NULL); 79 apid = AP_QID_CARD(q->apqn); 80 apqi = AP_QID_QUEUE(q->apqn); 81 vfio_ap_mdev_reset_queue(apid, apqi, 1); 82 vfio_ap_irq_disable(q); 83 kfree(q); 84 mutex_unlock(&matrix_dev->lock); 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 memset(&vfio_ap_drv, 0, sizeof(vfio_ap_drv)); 189 vfio_ap_drv.probe = vfio_ap_queue_dev_probe; 190 vfio_ap_drv.remove = vfio_ap_queue_dev_remove; 191 vfio_ap_drv.ids = ap_queue_ids; 192 193 ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); 194 if (ret) { 195 vfio_ap_matrix_dev_destroy(); 196 return ret; 197 } 198 199 ret = vfio_ap_mdev_register(); 200 if (ret) { 201 ap_driver_unregister(&vfio_ap_drv); 202 vfio_ap_matrix_dev_destroy(); 203 204 return ret; 205 } 206 207 return 0; 208 } 209 210 static void __exit vfio_ap_exit(void) 211 { 212 vfio_ap_mdev_unregister(); 213 ap_driver_unregister(&vfio_ap_drv); 214 vfio_ap_matrix_dev_destroy(); 215 } 216 217 module_init(vfio_ap_init); 218 module_exit(vfio_ap_exit); 219