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 { /* 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 int apid, apqi; 73 74 mutex_lock(&matrix_dev->lock); 75 q = dev_get_drvdata(&apdev->device); 76 dev_set_drvdata(&apdev->device, NULL); 77 apid = AP_QID_CARD(q->apqn); 78 apqi = AP_QID_QUEUE(q->apqn); 79 vfio_ap_mdev_reset_queue(apid, apqi, 1); 80 vfio_ap_irq_disable(q); 81 kfree(q); 82 mutex_unlock(&matrix_dev->lock); 83 } 84 85 static void vfio_ap_matrix_dev_release(struct device *dev) 86 { 87 struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev); 88 89 kfree(matrix_dev); 90 } 91 92 static int matrix_bus_match(struct device *dev, struct device_driver *drv) 93 { 94 return 1; 95 } 96 97 static struct bus_type matrix_bus = { 98 .name = "matrix", 99 .match = &matrix_bus_match, 100 }; 101 102 static struct device_driver matrix_driver = { 103 .name = "vfio_ap", 104 .bus = &matrix_bus, 105 .suppress_bind_attrs = true, 106 }; 107 108 static int vfio_ap_matrix_dev_create(void) 109 { 110 int ret; 111 struct device *root_device; 112 113 root_device = root_device_register(VFIO_AP_ROOT_NAME); 114 if (IS_ERR(root_device)) 115 return PTR_ERR(root_device); 116 117 ret = bus_register(&matrix_bus); 118 if (ret) 119 goto bus_register_err; 120 121 matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL); 122 if (!matrix_dev) { 123 ret = -ENOMEM; 124 goto matrix_alloc_err; 125 } 126 127 /* Fill in config info via PQAP(QCI), if available */ 128 if (test_facility(12)) { 129 ret = ap_qci(&matrix_dev->info); 130 if (ret) 131 goto matrix_alloc_err; 132 } 133 134 mutex_init(&matrix_dev->lock); 135 INIT_LIST_HEAD(&matrix_dev->mdev_list); 136 137 dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME); 138 matrix_dev->device.parent = root_device; 139 matrix_dev->device.bus = &matrix_bus; 140 matrix_dev->device.release = vfio_ap_matrix_dev_release; 141 matrix_dev->vfio_ap_drv = &vfio_ap_drv; 142 143 ret = device_register(&matrix_dev->device); 144 if (ret) 145 goto matrix_reg_err; 146 147 ret = driver_register(&matrix_driver); 148 if (ret) 149 goto matrix_drv_err; 150 151 return 0; 152 153 matrix_drv_err: 154 device_unregister(&matrix_dev->device); 155 matrix_reg_err: 156 put_device(&matrix_dev->device); 157 matrix_alloc_err: 158 bus_unregister(&matrix_bus); 159 bus_register_err: 160 root_device_unregister(root_device); 161 return ret; 162 } 163 164 static void vfio_ap_matrix_dev_destroy(void) 165 { 166 struct device *root_device = matrix_dev->device.parent; 167 168 driver_unregister(&matrix_driver); 169 device_unregister(&matrix_dev->device); 170 bus_unregister(&matrix_bus); 171 root_device_unregister(root_device); 172 } 173 174 static int __init vfio_ap_init(void) 175 { 176 int ret; 177 178 /* If there are no AP instructions, there is nothing to pass through. */ 179 if (!ap_instructions_available()) 180 return -ENODEV; 181 182 ret = vfio_ap_matrix_dev_create(); 183 if (ret) 184 return ret; 185 186 memset(&vfio_ap_drv, 0, sizeof(vfio_ap_drv)); 187 vfio_ap_drv.probe = vfio_ap_queue_dev_probe; 188 vfio_ap_drv.remove = vfio_ap_queue_dev_remove; 189 vfio_ap_drv.ids = ap_queue_ids; 190 191 ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); 192 if (ret) { 193 vfio_ap_matrix_dev_destroy(); 194 return ret; 195 } 196 197 ret = vfio_ap_mdev_register(); 198 if (ret) { 199 ap_driver_unregister(&vfio_ap_drv); 200 vfio_ap_matrix_dev_destroy(); 201 202 return ret; 203 } 204 205 return 0; 206 } 207 208 static void __exit vfio_ap_exit(void) 209 { 210 vfio_ap_mdev_unregister(); 211 ap_driver_unregister(&vfio_ap_drv); 212 vfio_ap_matrix_dev_destroy(); 213 } 214 215 module_init(vfio_ap_init); 216 module_exit(vfio_ap_exit); 217