1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2017 Netronome Systems, Inc.
3 * Copyright (C) 2019 Mellanox Technologies. All rights reserved
4 */
5
6 #include <linux/device.h>
7 #include <linux/idr.h>
8 #include <linux/kernel.h>
9 #include <linux/list.h>
10 #include <linux/mutex.h>
11 #include <linux/slab.h>
12 #include <linux/sysfs.h>
13
14 #include "netdevsim.h"
15
16 static DEFINE_IDA(nsim_bus_dev_ids);
17 static LIST_HEAD(nsim_bus_dev_list);
18 static DEFINE_MUTEX(nsim_bus_dev_list_lock);
19 static bool nsim_bus_enable;
20
to_nsim_bus_dev(struct device * dev)21 static struct nsim_bus_dev *to_nsim_bus_dev(struct device *dev)
22 {
23 return container_of(dev, struct nsim_bus_dev, dev);
24 }
25
26 static ssize_t
nsim_bus_dev_numvfs_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)27 nsim_bus_dev_numvfs_store(struct device *dev, struct device_attribute *attr,
28 const char *buf, size_t count)
29 {
30 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
31 unsigned int num_vfs;
32 int ret;
33
34 ret = kstrtouint(buf, 0, &num_vfs);
35 if (ret)
36 return ret;
37
38 device_lock(dev);
39 ret = -ENOENT;
40 if (dev_get_drvdata(dev))
41 ret = nsim_drv_configure_vfs(nsim_bus_dev, num_vfs);
42 device_unlock(dev);
43
44 return ret ? ret : count;
45 }
46
47 static ssize_t
nsim_bus_dev_numvfs_show(struct device * dev,struct device_attribute * attr,char * buf)48 nsim_bus_dev_numvfs_show(struct device *dev,
49 struct device_attribute *attr, char *buf)
50 {
51 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
52
53 return sprintf(buf, "%u\n", nsim_bus_dev->num_vfs);
54 }
55
56 static struct device_attribute nsim_bus_dev_numvfs_attr =
57 __ATTR(sriov_numvfs, 0664, nsim_bus_dev_numvfs_show,
58 nsim_bus_dev_numvfs_store);
59
60 static ssize_t
new_port_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)61 new_port_store(struct device *dev, struct device_attribute *attr,
62 const char *buf, size_t count)
63 {
64 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
65 unsigned int port_index;
66 int ret;
67
68 /* Prevent to use nsim_bus_dev before initialization. */
69 if (!smp_load_acquire(&nsim_bus_dev->init))
70 return -EBUSY;
71 ret = kstrtouint(buf, 0, &port_index);
72 if (ret)
73 return ret;
74
75 ret = nsim_drv_port_add(nsim_bus_dev, NSIM_DEV_PORT_TYPE_PF, port_index);
76 return ret ? ret : count;
77 }
78
79 static struct device_attribute nsim_bus_dev_new_port_attr = __ATTR_WO(new_port);
80
81 static ssize_t
del_port_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)82 del_port_store(struct device *dev, struct device_attribute *attr,
83 const char *buf, size_t count)
84 {
85 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
86 unsigned int port_index;
87 int ret;
88
89 /* Prevent to use nsim_bus_dev before initialization. */
90 if (!smp_load_acquire(&nsim_bus_dev->init))
91 return -EBUSY;
92 ret = kstrtouint(buf, 0, &port_index);
93 if (ret)
94 return ret;
95
96 ret = nsim_drv_port_del(nsim_bus_dev, NSIM_DEV_PORT_TYPE_PF, port_index);
97 return ret ? ret : count;
98 }
99
100 static struct device_attribute nsim_bus_dev_del_port_attr = __ATTR_WO(del_port);
101
102 static struct attribute *nsim_bus_dev_attrs[] = {
103 &nsim_bus_dev_numvfs_attr.attr,
104 &nsim_bus_dev_new_port_attr.attr,
105 &nsim_bus_dev_del_port_attr.attr,
106 NULL,
107 };
108
109 static const struct attribute_group nsim_bus_dev_attr_group = {
110 .attrs = nsim_bus_dev_attrs,
111 };
112
113 static const struct attribute_group *nsim_bus_dev_attr_groups[] = {
114 &nsim_bus_dev_attr_group,
115 NULL,
116 };
117
nsim_bus_dev_release(struct device * dev)118 static void nsim_bus_dev_release(struct device *dev)
119 {
120 struct nsim_bus_dev *nsim_bus_dev;
121
122 nsim_bus_dev = container_of(dev, struct nsim_bus_dev, dev);
123 kfree(nsim_bus_dev);
124 }
125
126 static struct device_type nsim_bus_dev_type = {
127 .groups = nsim_bus_dev_attr_groups,
128 .release = nsim_bus_dev_release,
129 };
130
131 static struct nsim_bus_dev *
132 nsim_bus_dev_new(unsigned int id, unsigned int port_count, unsigned int num_queues);
133
134 static ssize_t
new_device_store(const struct bus_type * bus,const char * buf,size_t count)135 new_device_store(const struct bus_type *bus, const char *buf, size_t count)
136 {
137 unsigned int id, port_count, num_queues;
138 struct nsim_bus_dev *nsim_bus_dev;
139 int err;
140
141 err = sscanf(buf, "%u %u %u", &id, &port_count, &num_queues);
142 switch (err) {
143 case 1:
144 port_count = 1;
145 fallthrough;
146 case 2:
147 num_queues = 1;
148 fallthrough;
149 case 3:
150 if (id > INT_MAX) {
151 pr_err("Value of \"id\" is too big.\n");
152 return -EINVAL;
153 }
154 break;
155 default:
156 pr_err("Format for adding new device is \"id port_count num_queues\" (uint uint unit).\n");
157 return -EINVAL;
158 }
159
160 mutex_lock(&nsim_bus_dev_list_lock);
161 /* Prevent to use resource before initialization. */
162 if (!smp_load_acquire(&nsim_bus_enable)) {
163 err = -EBUSY;
164 goto err;
165 }
166
167 nsim_bus_dev = nsim_bus_dev_new(id, port_count, num_queues);
168 if (IS_ERR(nsim_bus_dev)) {
169 err = PTR_ERR(nsim_bus_dev);
170 goto err;
171 }
172
173 /* Allow using nsim_bus_dev */
174 smp_store_release(&nsim_bus_dev->init, true);
175
176 list_add_tail(&nsim_bus_dev->list, &nsim_bus_dev_list);
177 mutex_unlock(&nsim_bus_dev_list_lock);
178
179 return count;
180 err:
181 mutex_unlock(&nsim_bus_dev_list_lock);
182 return err;
183 }
184 static BUS_ATTR_WO(new_device);
185
186 static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev);
187
188 static ssize_t
del_device_store(const struct bus_type * bus,const char * buf,size_t count)189 del_device_store(const struct bus_type *bus, const char *buf, size_t count)
190 {
191 struct nsim_bus_dev *nsim_bus_dev, *tmp;
192 unsigned int id;
193 int err;
194
195 err = sscanf(buf, "%u", &id);
196 switch (err) {
197 case 1:
198 if (id > INT_MAX) {
199 pr_err("Value of \"id\" is too big.\n");
200 return -EINVAL;
201 }
202 break;
203 default:
204 pr_err("Format for deleting device is \"id\" (uint).\n");
205 return -EINVAL;
206 }
207
208 err = -ENOENT;
209 mutex_lock(&nsim_bus_dev_list_lock);
210 /* Prevent to use resource before initialization. */
211 if (!smp_load_acquire(&nsim_bus_enable)) {
212 mutex_unlock(&nsim_bus_dev_list_lock);
213 return -EBUSY;
214 }
215 list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) {
216 if (nsim_bus_dev->dev.id != id)
217 continue;
218 list_del(&nsim_bus_dev->list);
219 nsim_bus_dev_del(nsim_bus_dev);
220 err = 0;
221 break;
222 }
223 mutex_unlock(&nsim_bus_dev_list_lock);
224 return !err ? count : err;
225 }
226 static BUS_ATTR_WO(del_device);
227
228 static struct attribute *nsim_bus_attrs[] = {
229 &bus_attr_new_device.attr,
230 &bus_attr_del_device.attr,
231 NULL
232 };
233 ATTRIBUTE_GROUPS(nsim_bus);
234
nsim_bus_probe(struct device * dev)235 static int nsim_bus_probe(struct device *dev)
236 {
237 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
238
239 return nsim_drv_probe(nsim_bus_dev);
240 }
241
nsim_bus_remove(struct device * dev)242 static void nsim_bus_remove(struct device *dev)
243 {
244 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
245
246 nsim_drv_remove(nsim_bus_dev);
247 }
248
nsim_num_vf(struct device * dev)249 static int nsim_num_vf(struct device *dev)
250 {
251 struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
252
253 return nsim_bus_dev->num_vfs;
254 }
255
256 static struct bus_type nsim_bus = {
257 .name = DRV_NAME,
258 .dev_name = DRV_NAME,
259 .bus_groups = nsim_bus_groups,
260 .probe = nsim_bus_probe,
261 .remove = nsim_bus_remove,
262 .num_vf = nsim_num_vf,
263 };
264
265 #define NSIM_BUS_DEV_MAX_VFS 4
266
267 static struct nsim_bus_dev *
nsim_bus_dev_new(unsigned int id,unsigned int port_count,unsigned int num_queues)268 nsim_bus_dev_new(unsigned int id, unsigned int port_count, unsigned int num_queues)
269 {
270 struct nsim_bus_dev *nsim_bus_dev;
271 int err;
272
273 nsim_bus_dev = kzalloc(sizeof(*nsim_bus_dev), GFP_KERNEL);
274 if (!nsim_bus_dev)
275 return ERR_PTR(-ENOMEM);
276
277 err = ida_alloc_range(&nsim_bus_dev_ids, id, id, GFP_KERNEL);
278 if (err < 0)
279 goto err_nsim_bus_dev_free;
280 nsim_bus_dev->dev.id = err;
281 nsim_bus_dev->dev.bus = &nsim_bus;
282 nsim_bus_dev->dev.type = &nsim_bus_dev_type;
283 nsim_bus_dev->port_count = port_count;
284 nsim_bus_dev->num_queues = num_queues;
285 nsim_bus_dev->initial_net = current->nsproxy->net_ns;
286 nsim_bus_dev->max_vfs = NSIM_BUS_DEV_MAX_VFS;
287 /* Disallow using nsim_bus_dev */
288 smp_store_release(&nsim_bus_dev->init, false);
289
290 err = device_register(&nsim_bus_dev->dev);
291 if (err)
292 goto err_nsim_bus_dev_id_free;
293
294 return nsim_bus_dev;
295
296 err_nsim_bus_dev_id_free:
297 ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id);
298 put_device(&nsim_bus_dev->dev);
299 nsim_bus_dev = NULL;
300 err_nsim_bus_dev_free:
301 kfree(nsim_bus_dev);
302 return ERR_PTR(err);
303 }
304
nsim_bus_dev_del(struct nsim_bus_dev * nsim_bus_dev)305 static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev)
306 {
307 /* Disallow using nsim_bus_dev */
308 smp_store_release(&nsim_bus_dev->init, false);
309 ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id);
310 device_unregister(&nsim_bus_dev->dev);
311 }
312
313 static struct device_driver nsim_driver = {
314 .name = DRV_NAME,
315 .bus = &nsim_bus,
316 .owner = THIS_MODULE,
317 };
318
nsim_bus_init(void)319 int nsim_bus_init(void)
320 {
321 int err;
322
323 err = bus_register(&nsim_bus);
324 if (err)
325 return err;
326 err = driver_register(&nsim_driver);
327 if (err)
328 goto err_bus_unregister;
329 /* Allow using resources */
330 smp_store_release(&nsim_bus_enable, true);
331 return 0;
332
333 err_bus_unregister:
334 bus_unregister(&nsim_bus);
335 return err;
336 }
337
nsim_bus_exit(void)338 void nsim_bus_exit(void)
339 {
340 struct nsim_bus_dev *nsim_bus_dev, *tmp;
341
342 /* Disallow using resources */
343 smp_store_release(&nsim_bus_enable, false);
344
345 mutex_lock(&nsim_bus_dev_list_lock);
346 list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) {
347 list_del(&nsim_bus_dev->list);
348 nsim_bus_dev_del(nsim_bus_dev);
349 }
350 mutex_unlock(&nsim_bus_dev_list_lock);
351
352 driver_unregister(&nsim_driver);
353 bus_unregister(&nsim_bus);
354 }
355
