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 
vfio_ap_matrix_dev_release(struct device * dev)55 static void vfio_ap_matrix_dev_release(struct device *dev)
56 {
57 	struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev);
58 
59 	kfree(matrix_dev);
60 }
61 
matrix_bus_match(struct device * dev,struct device_driver * drv)62 static int matrix_bus_match(struct device *dev, struct device_driver *drv)
63 {
64 	return 1;
65 }
66 
67 static struct bus_type matrix_bus = {
68 	.name = "matrix",
69 	.match = &matrix_bus_match,
70 };
71 
72 static struct device_driver matrix_driver = {
73 	.name = "vfio_ap",
74 	.bus = &matrix_bus,
75 	.suppress_bind_attrs = true,
76 };
77 
vfio_ap_matrix_dev_create(void)78 static int vfio_ap_matrix_dev_create(void)
79 {
80 	int ret;
81 	struct device *root_device;
82 
83 	root_device = root_device_register(VFIO_AP_ROOT_NAME);
84 	if (IS_ERR(root_device))
85 		return PTR_ERR(root_device);
86 
87 	ret = bus_register(&matrix_bus);
88 	if (ret)
89 		goto bus_register_err;
90 
91 	matrix_dev = kzalloc(sizeof(*matrix_dev), GFP_KERNEL);
92 	if (!matrix_dev) {
93 		ret = -ENOMEM;
94 		goto matrix_alloc_err;
95 	}
96 
97 	/* Fill in config info via PQAP(QCI), if available */
98 	if (test_facility(12)) {
99 		ret = ap_qci(&matrix_dev->info);
100 		if (ret)
101 			goto matrix_alloc_err;
102 	}
103 
104 	mutex_init(&matrix_dev->mdevs_lock);
105 	INIT_LIST_HEAD(&matrix_dev->mdev_list);
106 	mutex_init(&matrix_dev->guests_lock);
107 
108 	dev_set_name(&matrix_dev->device, "%s", VFIO_AP_DEV_NAME);
109 	matrix_dev->device.parent = root_device;
110 	matrix_dev->device.bus = &matrix_bus;
111 	matrix_dev->device.release = vfio_ap_matrix_dev_release;
112 	matrix_dev->vfio_ap_drv = &vfio_ap_drv;
113 
114 	ret = device_register(&matrix_dev->device);
115 	if (ret)
116 		goto matrix_reg_err;
117 
118 	ret = driver_register(&matrix_driver);
119 	if (ret)
120 		goto matrix_drv_err;
121 
122 	return 0;
123 
124 matrix_drv_err:
125 	device_unregister(&matrix_dev->device);
126 matrix_reg_err:
127 	put_device(&matrix_dev->device);
128 matrix_alloc_err:
129 	bus_unregister(&matrix_bus);
130 bus_register_err:
131 	root_device_unregister(root_device);
132 	return ret;
133 }
134 
vfio_ap_matrix_dev_destroy(void)135 static void vfio_ap_matrix_dev_destroy(void)
136 {
137 	struct device *root_device = matrix_dev->device.parent;
138 
139 	driver_unregister(&matrix_driver);
140 	device_unregister(&matrix_dev->device);
141 	bus_unregister(&matrix_bus);
142 	root_device_unregister(root_device);
143 }
144 
vfio_ap_dbf_info_init(void)145 static int __init vfio_ap_dbf_info_init(void)
146 {
147 	vfio_ap_dbf_info = debug_register("vfio_ap", 1, 1,
148 					  DBF_MAX_SPRINTF_ARGS * sizeof(long));
149 
150 	if (!vfio_ap_dbf_info)
151 		return -ENOENT;
152 
153 	debug_register_view(vfio_ap_dbf_info, &debug_sprintf_view);
154 	debug_set_level(vfio_ap_dbf_info, DBF_WARN);
155 
156 	return 0;
157 }
158 
vfio_ap_init(void)159 static int __init vfio_ap_init(void)
160 {
161 	int ret;
162 
163 	ret = vfio_ap_dbf_info_init();
164 	if (ret)
165 		return ret;
166 
167 	/* If there are no AP instructions, there is nothing to pass through. */
168 	if (!ap_instructions_available())
169 		return -ENODEV;
170 
171 	ret = vfio_ap_matrix_dev_create();
172 	if (ret)
173 		return ret;
174 
175 	ret = ap_driver_register(&vfio_ap_drv, THIS_MODULE, VFIO_AP_DRV_NAME);
176 	if (ret) {
177 		vfio_ap_matrix_dev_destroy();
178 		return ret;
179 	}
180 
181 	ret = vfio_ap_mdev_register();
182 	if (ret) {
183 		ap_driver_unregister(&vfio_ap_drv);
184 		vfio_ap_matrix_dev_destroy();
185 
186 		return ret;
187 	}
188 
189 	return 0;
190 }
191 
vfio_ap_exit(void)192 static void __exit vfio_ap_exit(void)
193 {
194 	vfio_ap_mdev_unregister();
195 	ap_driver_unregister(&vfio_ap_drv);
196 	vfio_ap_matrix_dev_destroy();
197 	debug_unregister(vfio_ap_dbf_info);
198 }
199 
200 module_init(vfio_ap_init);
201 module_exit(vfio_ap_exit);
202