xref: /openbmc/linux/drivers/s390/crypto/vfio_ap_drv.c (revision 0c15d66d071c3490a9a3004b5a4c6f7524041a99)
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 int matrix_bus_match(struct device *dev, struct device_driver *drv)
64 {
65 	return 1;
66 }
67 
68 static struct bus_type matrix_bus = {
69 	.name = "matrix",
70 	.match = &matrix_bus_match,
71 };
72 
73 static struct device_driver matrix_driver = {
74 	.name = "vfio_ap",
75 	.bus = &matrix_bus,
76 	.suppress_bind_attrs = true,
77 };
78 
79 static int vfio_ap_matrix_dev_create(void)
80 {
81 	int ret;
82 	struct device *root_device;
83 
84 	root_device = root_device_register(VFIO_AP_ROOT_NAME);
85 	if (IS_ERR(root_device))
86 		return PTR_ERR(root_device);
87 
88 	ret = bus_register(&matrix_bus);
89 	if (ret)
90 		goto bus_register_err;
91 
92 	matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
93 	if (!matrix_dev) {
94 		ret = -ENOMEM;
95 		goto matrix_alloc_err;
96 	}
97 
98 	/* Fill in config info via PQAP(QCI), if available */
99 	if (test_facility(12)) {
100 		ret = ap_qci(&matrix_dev->info);
101 		if (ret)
102 			goto matrix_alloc_err;
103 	}
104 
105 	mutex_init(&matrix_dev->mdevs_lock);
106 	INIT_LIST_HEAD(&matrix_dev->mdev_list);
107 	mutex_init(&matrix_dev->guests_lock);
108 
109 	dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME);
110 	matrix_dev->device.parent = root_device;
111 	matrix_dev->device.bus = &matrix_bus;
112 	matrix_dev->device.release = vfio_ap_matrix_dev_release;
113 	matrix_dev->vfio_ap_drv = &vfio_ap_drv;
114 
115 	ret = device_register(&matrix_dev->device);
116 	if (ret)
117 		goto matrix_reg_err;
118 
119 	ret = driver_register(&matrix_driver);
120 	if (ret)
121 		goto matrix_drv_err;
122 
123 	return 0;
124 
125 matrix_drv_err:
126 	device_del(&matrix_dev->device);
127 matrix_reg_err:
128 	put_device(&matrix_dev->device);
129 matrix_alloc_err:
130 	bus_unregister(&matrix_bus);
131 bus_register_err:
132 	root_device_unregister(root_device);
133 	return ret;
134 }
135 
136 static void vfio_ap_matrix_dev_destroy(void)
137 {
138 	struct device *root_device = matrix_dev->device.parent;
139 
140 	driver_unregister(&matrix_driver);
141 	device_unregister(&matrix_dev->device);
142 	bus_unregister(&matrix_bus);
143 	root_device_unregister(root_device);
144 }
145 
146 static int __init vfio_ap_dbf_info_init(void)
147 {
148 	vfio_ap_dbf_info = debug_register("vfio_ap", 1, 1,
149 					  DBF_MAX_SPRINTF_ARGS * sizeof(long));
150 
151 	if (!vfio_ap_dbf_info)
152 		return -ENOENT;
153 
154 	debug_register_view(vfio_ap_dbf_info, &debug_sprintf_view);
155 	debug_set_level(vfio_ap_dbf_info, DBF_WARN);
156 
157 	return 0;
158 }
159 
160 static int __init vfio_ap_init(void)
161 {
162 	int ret;
163 
164 	ret = vfio_ap_dbf_info_init();
165 	if (ret)
166 		return ret;
167 
168 	/* If there are no AP instructions, there is nothing to pass through. */
169 	if (!ap_instructions_available())
170 		return -ENODEV;
171 
172 	ret = vfio_ap_matrix_dev_create();
173 	if (ret)
174 		return ret;
175 
176 	ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME);
177 	if (ret) {
178 		vfio_ap_matrix_dev_destroy();
179 		return ret;
180 	}
181 
182 	ret = vfio_ap_mdev_register();
183 	if (ret) {
184 		ap_driver_unregister(&vfio_ap_drv);
185 		vfio_ap_matrix_dev_destroy();
186 
187 		return ret;
188 	}
189 
190 	return 0;
191 }
192 
193 static void __exit vfio_ap_exit(void)
194 {
195 	vfio_ap_mdev_unregister();
196 	ap_driver_unregister(&vfio_ap_drv);
197 	vfio_ap_matrix_dev_destroy();
198 	debug_unregister(vfio_ap_dbf_info);
199 }
200 
201 module_init(vfio_ap_init);
202 module_exit(vfio_ap_exit);
203