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 */ 9 10 #include <linux/module.h> 11 #include <linux/mod_devicetable.h> 12 #include <linux/slab.h> 13 #include <linux/string.h> 14 #include <asm/facility.h> 15 #include "vfio_ap_private.h" 16 17 #define VFIO_AP_ROOT_NAME "vfio_ap" 18 #define VFIO_AP_DEV_TYPE_NAME "ap_matrix" 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 static struct device_type vfio_ap_dev_type = { 28 .name = VFIO_AP_DEV_TYPE_NAME, 29 }; 30 31 struct ap_matrix_dev *matrix_dev; 32 33 /* Only type 10 adapters (CEX4 and later) are supported 34 * by the AP matrix device driver 35 */ 36 static struct ap_device_id ap_queue_ids[] = { 37 { .dev_type = AP_DEVICE_TYPE_CEX4, 38 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 39 { .dev_type = AP_DEVICE_TYPE_CEX5, 40 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 41 { .dev_type = AP_DEVICE_TYPE_CEX6, 42 .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE }, 43 { /* end of sibling */ }, 44 }; 45 46 MODULE_DEVICE_TABLE(vfio_ap, ap_queue_ids); 47 48 static int vfio_ap_queue_dev_probe(struct ap_device *apdev) 49 { 50 return 0; 51 } 52 53 static void vfio_ap_queue_dev_remove(struct ap_device *apdev) 54 { 55 /* Nothing to do yet */ 56 } 57 58 static void vfio_ap_matrix_dev_release(struct device *dev) 59 { 60 struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev); 61 62 kfree(matrix_dev); 63 } 64 65 static int vfio_ap_matrix_dev_create(void) 66 { 67 int ret; 68 struct device *root_device; 69 70 root_device = root_device_register(VFIO_AP_ROOT_NAME); 71 if (IS_ERR(root_device)) 72 return PTR_ERR(root_device); 73 74 matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL); 75 if (!matrix_dev) { 76 ret = -ENOMEM; 77 goto matrix_alloc_err; 78 } 79 80 /* Fill in config info via PQAP(QCI), if available */ 81 if (test_facility(12)) { 82 ret = ap_qci(&matrix_dev->info); 83 if (ret) 84 goto matrix_alloc_err; 85 } 86 87 mutex_init(&matrix_dev->lock); 88 INIT_LIST_HEAD(&matrix_dev->mdev_list); 89 90 matrix_dev->device.type = &vfio_ap_dev_type; 91 dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME); 92 matrix_dev->device.parent = root_device; 93 matrix_dev->device.release = vfio_ap_matrix_dev_release; 94 matrix_dev->device.driver = &vfio_ap_drv.driver; 95 96 ret = device_register(&matrix_dev->device); 97 if (ret) 98 goto matrix_reg_err; 99 100 return 0; 101 102 matrix_reg_err: 103 put_device(&matrix_dev->device); 104 matrix_alloc_err: 105 root_device_unregister(root_device); 106 107 return ret; 108 } 109 110 static void vfio_ap_matrix_dev_destroy(void) 111 { 112 device_unregister(&matrix_dev->device); 113 root_device_unregister(matrix_dev->device.parent); 114 } 115 116 static int __init vfio_ap_init(void) 117 { 118 int ret; 119 120 /* If there are no AP instructions, there is nothing to pass through. */ 121 if (!ap_instructions_available()) 122 return -ENODEV; 123 124 ret = vfio_ap_matrix_dev_create(); 125 if (ret) 126 return ret; 127 128 memset(&vfio_ap_drv, 0, sizeof(vfio_ap_drv)); 129 vfio_ap_drv.probe = vfio_ap_queue_dev_probe; 130 vfio_ap_drv.remove = vfio_ap_queue_dev_remove; 131 vfio_ap_drv.ids = ap_queue_ids; 132 133 ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME); 134 if (ret) { 135 vfio_ap_matrix_dev_destroy(); 136 return ret; 137 } 138 139 ret = vfio_ap_mdev_register(); 140 if (ret) { 141 ap_driver_unregister(&vfio_ap_drv); 142 vfio_ap_matrix_dev_destroy(); 143 144 return ret; 145 } 146 147 return 0; 148 } 149 150 static void __exit vfio_ap_exit(void) 151 { 152 vfio_ap_mdev_unregister(); 153 ap_driver_unregister(&vfio_ap_drv); 154 vfio_ap_matrix_dev_destroy(); 155 } 156 157 module_init(vfio_ap_init); 158 module_exit(vfio_ap_exit); 159