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 #include "vfio_ap_debug.h"
18 
19 #define VFIO_AP_ROOT_NAME "vfio_ap"
20 #define VFIO_AP_DEV_NAME "matrix"
21 
22 MODULE_AUTHOR("IBM Corporation");
23 MODULE_DESCRIPTION("VFIO AP device driver, Copyright IBM Corp. 2018");
24 MODULE_LICENSE("GPL v2");
25 
26 struct ap_matrix_dev *matrix_dev;
27 debug_info_t *vfio_ap_dbf_info;
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 	{ .dev_type = AP_DEVICE_TYPE_CEX8,
42 	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
43 	{ /* end of sibling */ },
44 };
45 
46 static struct ap_driver vfio_ap_drv = {
47 	.probe = vfio_ap_mdev_probe_queue,
48 	.remove = vfio_ap_mdev_remove_queue,
49 	.in_use = vfio_ap_mdev_resource_in_use,
50 	.on_config_changed = vfio_ap_on_cfg_changed,
51 	.on_scan_complete = vfio_ap_on_scan_complete,
52 	.ids = ap_queue_ids,
53 };
54 
55 static void vfio_ap_matrix_dev_release(struct device *dev)
56 {
57 	struct ap_matrix_dev *matrix_dev;
58 
59 	matrix_dev = container_of(dev, struct ap_matrix_dev, device);
60 	kfree(matrix_dev);
61 }
62 
63 static struct bus_type matrix_bus = {
64 	.name = "matrix",
65 };
66 
67 static struct device_driver matrix_driver = {
68 	.name = "vfio_ap",
69 	.bus = &matrix_bus,
70 	.suppress_bind_attrs = true,
71 };
72 
73 static int vfio_ap_matrix_dev_create(void)
74 {
75 	int ret;
76 	struct device *root_device;
77 
78 	root_device = root_device_register(VFIO_AP_ROOT_NAME);
79 	if (IS_ERR(root_device))
80 		return PTR_ERR(root_device);
81 
82 	ret = bus_register(&matrix_bus);
83 	if (ret)
84 		goto bus_register_err;
85 
86 	matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
87 	if (!matrix_dev) {
88 		ret = -ENOMEM;
89 		goto matrix_alloc_err;
90 	}
91 
92 	/* Fill in config info via PQAP(QCI), if available */
93 	if (test_facility(12)) {
94 		ret = ap_qci(&matrix_dev->info);
95 		if (ret)
96 			goto matrix_alloc_err;
97 	}
98 
99 	mutex_init(&matrix_dev->mdevs_lock);
100 	INIT_LIST_HEAD(&matrix_dev->mdev_list);
101 	mutex_init(&matrix_dev->guests_lock);
102 
103 	dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME);
104 	matrix_dev->device.parent = root_device;
105 	matrix_dev->device.bus = &matrix_bus;
106 	matrix_dev->device.release = vfio_ap_matrix_dev_release;
107 	matrix_dev->vfio_ap_drv = &vfio_ap_drv;
108 
109 	ret = device_register(&matrix_dev->device);
110 	if (ret)
111 		goto matrix_reg_err;
112 
113 	ret = driver_register(&matrix_driver);
114 	if (ret)
115 		goto matrix_drv_err;
116 
117 	return 0;
118 
119 matrix_drv_err:
120 	device_del(&matrix_dev->device);
121 matrix_reg_err:
122 	put_device(&matrix_dev->device);
123 matrix_alloc_err:
124 	bus_unregister(&matrix_bus);
125 bus_register_err:
126 	root_device_unregister(root_device);
127 	return ret;
128 }
129 
130 static void vfio_ap_matrix_dev_destroy(void)
131 {
132 	struct device *root_device = matrix_dev->device.parent;
133 
134 	driver_unregister(&matrix_driver);
135 	device_unregister(&matrix_dev->device);
136 	bus_unregister(&matrix_bus);
137 	root_device_unregister(root_device);
138 }
139 
140 static int __init vfio_ap_dbf_info_init(void)
141 {
142 	vfio_ap_dbf_info = debug_register("vfio_ap", 1, 1,
143 					  DBF_MAX_SPRINTF_ARGS * sizeof(long));
144 
145 	if (!vfio_ap_dbf_info)
146 		return -ENOENT;
147 
148 	debug_register_view(vfio_ap_dbf_info, &debug_sprintf_view);
149 	debug_set_level(vfio_ap_dbf_info, DBF_WARN);
150 
151 	return 0;
152 }
153 
154 static int __init vfio_ap_init(void)
155 {
156 	int ret;
157 
158 	ret = vfio_ap_dbf_info_init();
159 	if (ret)
160 		return ret;
161 
162 	/* If there are no AP instructions, there is nothing to pass through. */
163 	if (!ap_instructions_available())
164 		return -ENODEV;
165 
166 	ret = vfio_ap_matrix_dev_create();
167 	if (ret)
168 		return ret;
169 
170 	ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME);
171 	if (ret) {
172 		vfio_ap_matrix_dev_destroy();
173 		return ret;
174 	}
175 
176 	ret = vfio_ap_mdev_register();
177 	if (ret) {
178 		ap_driver_unregister(&vfio_ap_drv);
179 		vfio_ap_matrix_dev_destroy();
180 
181 		return ret;
182 	}
183 
184 	return 0;
185 }
186 
187 static void __exit vfio_ap_exit(void)
188 {
189 	vfio_ap_mdev_unregister();
190 	ap_driver_unregister(&vfio_ap_drv);
191 	vfio_ap_matrix_dev_destroy();
192 	debug_unregister(vfio_ap_dbf_info);
193 }
194 
195 module_init(vfio_ap_init);
196 module_exit(vfio_ap_exit);
197