1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) 2016 Mellanox Technologies. All rights reserved.
4 * Copyright (c) 2016 Jiri Pirko <jiri@mellanox.com>
5 */
6
7 #include <net/genetlink.h>
8
9 #include "devl_internal.h"
10
11 DEFINE_XARRAY_FLAGS(devlinks, XA_FLAGS_ALLOC);
12
devlink_priv(struct devlink * devlink)13 void *devlink_priv(struct devlink *devlink)
14 {
15 return &devlink->priv;
16 }
17 EXPORT_SYMBOL_GPL(devlink_priv);
18
priv_to_devlink(void * priv)19 struct devlink *priv_to_devlink(void *priv)
20 {
21 return container_of(priv, struct devlink, priv);
22 }
23 EXPORT_SYMBOL_GPL(priv_to_devlink);
24
devlink_to_dev(const struct devlink * devlink)25 struct device *devlink_to_dev(const struct devlink *devlink)
26 {
27 return devlink->dev;
28 }
29 EXPORT_SYMBOL_GPL(devlink_to_dev);
30
devlink_net(const struct devlink * devlink)31 struct net *devlink_net(const struct devlink *devlink)
32 {
33 return read_pnet(&devlink->_net);
34 }
35 EXPORT_SYMBOL_GPL(devlink_net);
36
devl_assert_locked(struct devlink * devlink)37 void devl_assert_locked(struct devlink *devlink)
38 {
39 lockdep_assert_held(&devlink->lock);
40 }
41 EXPORT_SYMBOL_GPL(devl_assert_locked);
42
43 #ifdef CONFIG_LOCKDEP
44 /* For use in conjunction with LOCKDEP only e.g. rcu_dereference_protected() */
devl_lock_is_held(struct devlink * devlink)45 bool devl_lock_is_held(struct devlink *devlink)
46 {
47 return lockdep_is_held(&devlink->lock);
48 }
49 EXPORT_SYMBOL_GPL(devl_lock_is_held);
50 #endif
51
devl_lock(struct devlink * devlink)52 void devl_lock(struct devlink *devlink)
53 {
54 mutex_lock(&devlink->lock);
55 }
56 EXPORT_SYMBOL_GPL(devl_lock);
57
devl_trylock(struct devlink * devlink)58 int devl_trylock(struct devlink *devlink)
59 {
60 return mutex_trylock(&devlink->lock);
61 }
62 EXPORT_SYMBOL_GPL(devl_trylock);
63
devl_unlock(struct devlink * devlink)64 void devl_unlock(struct devlink *devlink)
65 {
66 mutex_unlock(&devlink->lock);
67 }
68 EXPORT_SYMBOL_GPL(devl_unlock);
69
70 /**
71 * devlink_try_get() - try to obtain a reference on a devlink instance
72 * @devlink: instance to reference
73 *
74 * Obtain a reference on a devlink instance. A reference on a devlink instance
75 * only implies that it's safe to take the instance lock. It does not imply
76 * that the instance is registered, use devl_is_registered() after taking
77 * the instance lock to check registration status.
78 */
devlink_try_get(struct devlink * devlink)79 struct devlink *__must_check devlink_try_get(struct devlink *devlink)
80 {
81 if (refcount_inc_not_zero(&devlink->refcount))
82 return devlink;
83 return NULL;
84 }
85
devlink_release(struct work_struct * work)86 static void devlink_release(struct work_struct *work)
87 {
88 struct devlink *devlink;
89
90 devlink = container_of(to_rcu_work(work), struct devlink, rwork);
91
92 mutex_destroy(&devlink->lock);
93 lockdep_unregister_key(&devlink->lock_key);
94 kfree(devlink);
95 }
96
devlink_put(struct devlink * devlink)97 void devlink_put(struct devlink *devlink)
98 {
99 if (refcount_dec_and_test(&devlink->refcount))
100 queue_rcu_work(system_wq, &devlink->rwork);
101 }
102
devlinks_xa_find_get(struct net * net,unsigned long * indexp)103 struct devlink *devlinks_xa_find_get(struct net *net, unsigned long *indexp)
104 {
105 struct devlink *devlink = NULL;
106
107 rcu_read_lock();
108 retry:
109 devlink = xa_find(&devlinks, indexp, ULONG_MAX, DEVLINK_REGISTERED);
110 if (!devlink)
111 goto unlock;
112
113 if (!devlink_try_get(devlink))
114 goto next;
115 if (!net_eq(devlink_net(devlink), net)) {
116 devlink_put(devlink);
117 goto next;
118 }
119 unlock:
120 rcu_read_unlock();
121 return devlink;
122
123 next:
124 (*indexp)++;
125 goto retry;
126 }
127
128 /**
129 * devl_register - Register devlink instance
130 * @devlink: devlink
131 */
devl_register(struct devlink * devlink)132 int devl_register(struct devlink *devlink)
133 {
134 ASSERT_DEVLINK_NOT_REGISTERED(devlink);
135 devl_assert_locked(devlink);
136
137 xa_set_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
138 devlink_notify_register(devlink);
139
140 return 0;
141 }
142 EXPORT_SYMBOL_GPL(devl_register);
143
devlink_register(struct devlink * devlink)144 void devlink_register(struct devlink *devlink)
145 {
146 devl_lock(devlink);
147 devl_register(devlink);
148 devl_unlock(devlink);
149 }
150 EXPORT_SYMBOL_GPL(devlink_register);
151
152 /**
153 * devl_unregister - Unregister devlink instance
154 * @devlink: devlink
155 */
devl_unregister(struct devlink * devlink)156 void devl_unregister(struct devlink *devlink)
157 {
158 ASSERT_DEVLINK_REGISTERED(devlink);
159 devl_assert_locked(devlink);
160
161 devlink_notify_unregister(devlink);
162 xa_clear_mark(&devlinks, devlink->index, DEVLINK_REGISTERED);
163 }
164 EXPORT_SYMBOL_GPL(devl_unregister);
165
devlink_unregister(struct devlink * devlink)166 void devlink_unregister(struct devlink *devlink)
167 {
168 devl_lock(devlink);
169 devl_unregister(devlink);
170 devl_unlock(devlink);
171 }
172 EXPORT_SYMBOL_GPL(devlink_unregister);
173
174 /**
175 * devlink_alloc_ns - Allocate new devlink instance resources
176 * in specific namespace
177 *
178 * @ops: ops
179 * @priv_size: size of user private data
180 * @net: net namespace
181 * @dev: parent device
182 *
183 * Allocate new devlink instance resources, including devlink index
184 * and name.
185 */
devlink_alloc_ns(const struct devlink_ops * ops,size_t priv_size,struct net * net,struct device * dev)186 struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
187 size_t priv_size, struct net *net,
188 struct device *dev)
189 {
190 struct devlink *devlink;
191 static u32 last_id;
192 int ret;
193
194 WARN_ON(!ops || !dev);
195 if (!devlink_reload_actions_valid(ops))
196 return NULL;
197
198 devlink = kzalloc(sizeof(*devlink) + priv_size, GFP_KERNEL);
199 if (!devlink)
200 return NULL;
201
202 ret = xa_alloc_cyclic(&devlinks, &devlink->index, devlink, xa_limit_31b,
203 &last_id, GFP_KERNEL);
204 if (ret < 0)
205 goto err_xa_alloc;
206
207 devlink->netdevice_nb.notifier_call = devlink_port_netdevice_event;
208 ret = register_netdevice_notifier(&devlink->netdevice_nb);
209 if (ret)
210 goto err_register_netdevice_notifier;
211
212 devlink->dev = dev;
213 devlink->ops = ops;
214 xa_init_flags(&devlink->ports, XA_FLAGS_ALLOC);
215 xa_init_flags(&devlink->params, XA_FLAGS_ALLOC);
216 xa_init_flags(&devlink->snapshot_ids, XA_FLAGS_ALLOC);
217 write_pnet(&devlink->_net, net);
218 INIT_LIST_HEAD(&devlink->rate_list);
219 INIT_LIST_HEAD(&devlink->linecard_list);
220 INIT_LIST_HEAD(&devlink->sb_list);
221 INIT_LIST_HEAD_RCU(&devlink->dpipe_table_list);
222 INIT_LIST_HEAD(&devlink->resource_list);
223 INIT_LIST_HEAD(&devlink->region_list);
224 INIT_LIST_HEAD(&devlink->reporter_list);
225 INIT_LIST_HEAD(&devlink->trap_list);
226 INIT_LIST_HEAD(&devlink->trap_group_list);
227 INIT_LIST_HEAD(&devlink->trap_policer_list);
228 INIT_RCU_WORK(&devlink->rwork, devlink_release);
229 lockdep_register_key(&devlink->lock_key);
230 mutex_init(&devlink->lock);
231 lockdep_set_class(&devlink->lock, &devlink->lock_key);
232 refcount_set(&devlink->refcount, 1);
233
234 return devlink;
235
236 err_register_netdevice_notifier:
237 xa_erase(&devlinks, devlink->index);
238 err_xa_alloc:
239 kfree(devlink);
240 return NULL;
241 }
242 EXPORT_SYMBOL_GPL(devlink_alloc_ns);
243
244 /**
245 * devlink_free - Free devlink instance resources
246 *
247 * @devlink: devlink
248 */
devlink_free(struct devlink * devlink)249 void devlink_free(struct devlink *devlink)
250 {
251 ASSERT_DEVLINK_NOT_REGISTERED(devlink);
252
253 WARN_ON(!list_empty(&devlink->trap_policer_list));
254 WARN_ON(!list_empty(&devlink->trap_group_list));
255 WARN_ON(!list_empty(&devlink->trap_list));
256 WARN_ON(!list_empty(&devlink->reporter_list));
257 WARN_ON(!list_empty(&devlink->region_list));
258 WARN_ON(!list_empty(&devlink->resource_list));
259 WARN_ON(!list_empty(&devlink->dpipe_table_list));
260 WARN_ON(!list_empty(&devlink->sb_list));
261 WARN_ON(!list_empty(&devlink->rate_list));
262 WARN_ON(!list_empty(&devlink->linecard_list));
263 WARN_ON(!xa_empty(&devlink->ports));
264
265 xa_destroy(&devlink->snapshot_ids);
266 xa_destroy(&devlink->params);
267 xa_destroy(&devlink->ports);
268
269 WARN_ON_ONCE(unregister_netdevice_notifier(&devlink->netdevice_nb));
270
271 xa_erase(&devlinks, devlink->index);
272
273 devlink_put(devlink);
274 }
275 EXPORT_SYMBOL_GPL(devlink_free);
276
devlink_pernet_pre_exit(struct net * net)277 static void __net_exit devlink_pernet_pre_exit(struct net *net)
278 {
279 struct devlink *devlink;
280 u32 actions_performed;
281 unsigned long index;
282 int err;
283
284 /* In case network namespace is getting destroyed, reload
285 * all devlink instances from this namespace into init_net.
286 */
287 devlinks_xa_for_each_registered_get(net, index, devlink) {
288 devl_lock(devlink);
289 err = 0;
290 if (devl_is_registered(devlink))
291 err = devlink_reload(devlink, &init_net,
292 DEVLINK_RELOAD_ACTION_DRIVER_REINIT,
293 DEVLINK_RELOAD_LIMIT_UNSPEC,
294 &actions_performed, NULL);
295 devl_unlock(devlink);
296 devlink_put(devlink);
297 if (err && err != -EOPNOTSUPP)
298 pr_warn("Failed to reload devlink instance into init_net\n");
299 }
300 }
301
302 static struct pernet_operations devlink_pernet_ops __net_initdata = {
303 .pre_exit = devlink_pernet_pre_exit,
304 };
305
devlink_init(void)306 static int __init devlink_init(void)
307 {
308 int err;
309
310 err = genl_register_family(&devlink_nl_family);
311 if (err)
312 goto out;
313 err = register_pernet_subsys(&devlink_pernet_ops);
314
315 out:
316 WARN_ON(err);
317 return err;
318 }
319
320 subsys_initcall(devlink_init);
321