xref: /linux/drivers/s390/crypto/vfio_ap_drv.c (revision e08d227840bb9366c6321ae1e480b37ba5eec29b)
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 
features_show(struct device * dev,struct device_attribute * attr,char * buf)29 static ssize_t features_show(struct device *dev, struct device_attribute *attr, char *buf)
30 {
31 	return sysfs_emit(buf, "guest_matrix hotplug ap_config\n");
32 }
33 static DEVICE_ATTR_RO(features);
34 
35 static struct attribute *matrix_dev_attrs[] = {
36 	&dev_attr_features.attr,
37 	NULL,
38 };
39 ATTRIBUTE_GROUPS(matrix_dev);
40 
41 /* Only type 10 adapters (CEX4 and later) are supported
42  * by the AP matrix device driver
43  */
44 static struct ap_device_id ap_queue_ids[] = {
45 	{ .dev_type = AP_DEVICE_TYPE_CEX4,
46 	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
47 	{ .dev_type = AP_DEVICE_TYPE_CEX5,
48 	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
49 	{ .dev_type = AP_DEVICE_TYPE_CEX6,
50 	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
51 	{ .dev_type = AP_DEVICE_TYPE_CEX7,
52 	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
53 	{ .dev_type = AP_DEVICE_TYPE_CEX8,
54 	  .match_flags = AP_DEVICE_ID_MATCH_QUEUE_TYPE },
55 	{ /* end of sibling */ },
56 };
57 
58 static struct ap_driver vfio_ap_drv = {
59 	.probe = vfio_ap_mdev_probe_queue,
60 	.remove = vfio_ap_mdev_remove_queue,
61 	.in_use = vfio_ap_mdev_resource_in_use,
62 	.on_config_changed = vfio_ap_on_cfg_changed,
63 	.on_scan_complete = vfio_ap_on_scan_complete,
64 	.ids = ap_queue_ids,
65 };
66 
vfio_ap_matrix_dev_release(struct device * dev)67 static void vfio_ap_matrix_dev_release(struct device *dev)
68 {
69 	struct ap_matrix_dev *matrix_dev;
70 
71 	matrix_dev = container_of(dev, struct ap_matrix_dev, device);
72 	kfree(matrix_dev);
73 }
74 
75 static const struct bus_type matrix_bus = {
76 	.name = "matrix",
77 };
78 
79 static struct device_driver matrix_driver = {
80 	.name = "vfio_ap",
81 	.bus = &matrix_bus,
82 	.suppress_bind_attrs = true,
83 	.dev_groups = matrix_dev_groups,
84 };
85 
vfio_ap_matrix_dev_create(void)86 static int vfio_ap_matrix_dev_create(void)
87 {
88 	int ret;
89 	struct device *root_device;
90 
91 	root_device = root_device_register(VFIO_AP_ROOT_NAME);
92 	if (IS_ERR(root_device))
93 		return PTR_ERR(root_device);
94 
95 	ret = bus_register(&matrix_bus);
96 	if (ret)
97 		goto bus_register_err;
98 
99 	matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
100 	if (!matrix_dev) {
101 		ret = -ENOMEM;
102 		goto matrix_alloc_err;
103 	}
104 
105 	/* Fill in config info via PQAP(QCI), if available */
106 	if (test_facility(12)) {
107 		ret = ap_qci(&matrix_dev->info);
108 		if (ret)
109 			goto matrix_alloc_err;
110 	}
111 
112 	mutex_init(&matrix_dev->mdevs_lock);
113 	INIT_LIST_HEAD(&matrix_dev->mdev_list);
114 	mutex_init(&matrix_dev->guests_lock);
115 
116 	dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME);
117 	matrix_dev->device.parent = root_device;
118 	matrix_dev->device.bus = &matrix_bus;
119 	matrix_dev->device.release = vfio_ap_matrix_dev_release;
120 	matrix_dev->vfio_ap_drv = &vfio_ap_drv;
121 
122 	ret = device_register(&matrix_dev->device);
123 	if (ret)
124 		goto matrix_reg_err;
125 
126 	ret = driver_register(&matrix_driver);
127 	if (ret)
128 		goto matrix_drv_err;
129 
130 	return 0;
131 
132 matrix_drv_err:
133 	device_del(&matrix_dev->device);
134 matrix_reg_err:
135 	put_device(&matrix_dev->device);
136 matrix_alloc_err:
137 	bus_unregister(&matrix_bus);
138 bus_register_err:
139 	root_device_unregister(root_device);
140 	return ret;
141 }
142 
vfio_ap_matrix_dev_destroy(void)143 static void vfio_ap_matrix_dev_destroy(void)
144 {
145 	struct device *root_device = matrix_dev->device.parent;
146 
147 	driver_unregister(&matrix_driver);
148 	device_unregister(&matrix_dev->device);
149 	bus_unregister(&matrix_bus);
150 	root_device_unregister(root_device);
151 }
152 
vfio_ap_dbf_info_init(void)153 static int __init vfio_ap_dbf_info_init(void)
154 {
155 	vfio_ap_dbf_info = debug_register("vfio_ap", 1, 1,
156 					  DBF_MAX_SPRINTF_ARGS * sizeof(long));
157 
158 	if (!vfio_ap_dbf_info)
159 		return -ENOENT;
160 
161 	debug_register_view(vfio_ap_dbf_info, &debug_sprintf_view);
162 	debug_set_level(vfio_ap_dbf_info, DBF_WARN);
163 
164 	return 0;
165 }
166 
vfio_ap_init(void)167 static int __init vfio_ap_init(void)
168 {
169 	int ret;
170 
171 	ret = vfio_ap_dbf_info_init();
172 	if (ret)
173 		return ret;
174 
175 	/* If there are no AP instructions, there is nothing to pass through. */
176 	if (!ap_instructions_available())
177 		return -ENODEV;
178 
179 	ret = vfio_ap_matrix_dev_create();
180 	if (ret)
181 		return ret;
182 
183 	ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME);
184 	if (ret) {
185 		vfio_ap_matrix_dev_destroy();
186 		return ret;
187 	}
188 
189 	ret = vfio_ap_mdev_register();
190 	if (ret) {
191 		ap_driver_unregister(&vfio_ap_drv);
192 		vfio_ap_matrix_dev_destroy();
193 
194 		return ret;
195 	}
196 
197 	return 0;
198 }
199 
vfio_ap_exit(void)200 static void __exit vfio_ap_exit(void)
201 {
202 	vfio_ap_mdev_unregister();
203 	ap_driver_unregister(&vfio_ap_drv);
204 	vfio_ap_matrix_dev_destroy();
205 	debug_unregister(vfio_ap_dbf_info);
206 }
207 
208 module_init(vfio_ap_init);
209 module_exit(vfio_ap_exit);
210