1// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
2/* Copyright (c) 2020 Mellanox Technologies. */
3
4#include <linux/refcount.h>
5#include <linux/list.h>
6#include <linux/rculist.h>
7#include <linux/rtnetlink.h>
8#include <linux/workqueue.h>
9#include <linux/spinlock.h>
10#include <linux/notifier.h>
11#include <net/netevent.h>
12#include <net/arp.h>
13#include "neigh.h"
14#include "tc.h"
15#include "en_rep.h"
16#include "fs_core.h"
17#include "diag/en_rep_tracepoint.h"
18
19static unsigned long mlx5e_rep_ipv6_interval(void)
20{
21 if (IS_ENABLED(CONFIG_IPV6) && ipv6_stub->nd_tbl)
22 return NEIGH_VAR(&ipv6_stub->nd_tbl->parms, DELAY_PROBE_TIME);
23
24 return ~0UL;
25}
26
27static void mlx5e_rep_neigh_update_init_interval(struct mlx5e_rep_priv *rpriv)
28{
29 unsigned long ipv4_interval = NEIGH_VAR(&arp_tbl.parms, DELAY_PROBE_TIME);
30 unsigned long ipv6_interval = mlx5e_rep_ipv6_interval();
31 struct net_device *netdev = rpriv->netdev;
32 struct mlx5e_priv *priv = netdev_priv(dev: netdev);
33
34 rpriv->neigh_update.min_interval = min_t(unsigned long, ipv6_interval, ipv4_interval);
35 mlx5_fc_update_sampling_interval(dev: priv->mdev, interval: rpriv->neigh_update.min_interval);
36}
37
38void mlx5e_rep_queue_neigh_stats_work(struct mlx5e_priv *priv)
39{
40 struct mlx5e_rep_priv *rpriv = priv->ppriv;
41 struct mlx5e_neigh_update_table *neigh_update = &rpriv->neigh_update;
42
43 mlx5_fc_queue_stats_work(dev: priv->mdev,
44 dwork: &neigh_update->neigh_stats_work,
45 delay: neigh_update->min_interval);
46}
47
48static bool mlx5e_rep_neigh_entry_hold(struct mlx5e_neigh_hash_entry *nhe)
49{
50 return refcount_inc_not_zero(r: &nhe->refcnt);
51}
52
53static void mlx5e_rep_neigh_entry_remove(struct mlx5e_neigh_hash_entry *nhe);
54
55void mlx5e_rep_neigh_entry_release(struct mlx5e_neigh_hash_entry *nhe)
56{
57 if (refcount_dec_and_test(r: &nhe->refcnt)) {
58 mlx5e_rep_neigh_entry_remove(nhe);
59 kfree_rcu(nhe, rcu);
60 }
61}
62
63static struct mlx5e_neigh_hash_entry *
64mlx5e_get_next_nhe(struct mlx5e_rep_priv *rpriv,
65 struct mlx5e_neigh_hash_entry *nhe)
66{
67 struct mlx5e_neigh_hash_entry *next = NULL;
68
69 rcu_read_lock();
70
71 for (next = nhe ?
72 list_next_or_null_rcu(&rpriv->neigh_update.neigh_list,
73 &nhe->neigh_list,
74 struct mlx5e_neigh_hash_entry,
75 neigh_list) :
76 list_first_or_null_rcu(&rpriv->neigh_update.neigh_list,
77 struct mlx5e_neigh_hash_entry,
78 neigh_list);
79 next;
80 next = list_next_or_null_rcu(&rpriv->neigh_update.neigh_list,
81 &next->neigh_list,
82 struct mlx5e_neigh_hash_entry,
83 neigh_list))
84 if (mlx5e_rep_neigh_entry_hold(nhe: next))
85 break;
86
87 rcu_read_unlock();
88
89 if (nhe)
90 mlx5e_rep_neigh_entry_release(nhe);
91
92 return next;
93}
94
95static void mlx5e_rep_neigh_stats_work(struct work_struct *work)
96{
97 struct mlx5e_rep_priv *rpriv = container_of(work, struct mlx5e_rep_priv,
98 neigh_update.neigh_stats_work.work);
99 struct net_device *netdev = rpriv->netdev;
100 struct mlx5e_priv *priv = netdev_priv(dev: netdev);
101 struct mlx5e_neigh_hash_entry *nhe = NULL;
102
103 rtnl_lock();
104 if (!list_empty(head: &rpriv->neigh_update.neigh_list))
105 mlx5e_rep_queue_neigh_stats_work(priv);
106
107 while ((nhe = mlx5e_get_next_nhe(rpriv, nhe)) != NULL)
108 mlx5e_tc_update_neigh_used_value(nhe);
109
110 rtnl_unlock();
111}
112
113struct neigh_update_work {
114 struct work_struct work;
115 struct neighbour *n;
116 struct mlx5e_neigh_hash_entry *nhe;
117};
118
119static void mlx5e_release_neigh_update_work(struct neigh_update_work *update_work)
120{
121 neigh_release(neigh: update_work->n);
122 mlx5e_rep_neigh_entry_release(nhe: update_work->nhe);
123 kfree(objp: update_work);
124}
125
126static void mlx5e_rep_neigh_update(struct work_struct *work)
127{
128 struct neigh_update_work *update_work = container_of(work, struct neigh_update_work,
129 work);
130 struct mlx5e_neigh_hash_entry *nhe = update_work->nhe;
131 struct neighbour *n = update_work->n;
132 struct mlx5e_encap_entry *e = NULL;
133 bool neigh_connected, same_dev;
134 unsigned char ha[ETH_ALEN];
135 u8 nud_state, dead;
136
137 rtnl_lock();
138
139 /* If these parameters are changed after we release the lock,
140 * we'll receive another event letting us know about it.
141 * We use this lock to avoid inconsistency between the neigh validity
142 * and it's hw address.
143 */
144 read_lock_bh(&n->lock);
145 memcpy(ha, n->ha, ETH_ALEN);
146 nud_state = n->nud_state;
147 dead = n->dead;
148 same_dev = READ_ONCE(nhe->neigh_dev) == n->dev;
149 read_unlock_bh(&n->lock);
150
151 neigh_connected = (nud_state & NUD_VALID) && !dead;
152
153 trace_mlx5e_rep_neigh_update(nhe, ha, neigh_connected);
154
155 if (!same_dev)
156 goto out;
157
158 /* mlx5e_get_next_init_encap() releases previous encap before returning
159 * the next one.
160 */
161 while ((e = mlx5e_get_next_init_encap(nhe, e)) != NULL)
162 mlx5e_rep_update_flows(priv: netdev_priv(dev: e->out_dev), e, neigh_connected, ha);
163
164out:
165 rtnl_unlock();
166 mlx5e_release_neigh_update_work(update_work);
167}
168
169static struct neigh_update_work *mlx5e_alloc_neigh_update_work(struct mlx5e_priv *priv,
170 struct neighbour *n)
171{
172 struct neigh_update_work *update_work;
173 struct mlx5e_neigh_hash_entry *nhe;
174 struct mlx5e_neigh m_neigh = {};
175
176 update_work = kzalloc(sizeof(*update_work), GFP_ATOMIC);
177 if (WARN_ON(!update_work))
178 return NULL;
179
180 m_neigh.family = n->ops->family;
181 memcpy(&m_neigh.dst_ip, n->primary_key, n->tbl->key_len);
182
183 /* Obtain reference to nhe as last step in order not to release it in
184 * atomic context.
185 */
186 rcu_read_lock();
187 nhe = mlx5e_rep_neigh_entry_lookup(priv, m_neigh: &m_neigh);
188 rcu_read_unlock();
189 if (!nhe) {
190 kfree(objp: update_work);
191 return NULL;
192 }
193
194 INIT_WORK(&update_work->work, mlx5e_rep_neigh_update);
195 neigh_hold(n);
196 update_work->n = n;
197 update_work->nhe = nhe;
198
199 return update_work;
200}
201
202static int mlx5e_rep_netevent_event(struct notifier_block *nb,
203 unsigned long event, void *ptr)
204{
205 struct mlx5e_rep_priv *rpriv = container_of(nb, struct mlx5e_rep_priv,
206 neigh_update.netevent_nb);
207 struct mlx5e_neigh_update_table *neigh_update = &rpriv->neigh_update;
208 struct net_device *netdev = rpriv->netdev;
209 struct mlx5e_priv *priv = netdev_priv(dev: netdev);
210 struct mlx5e_neigh_hash_entry *nhe = NULL;
211 struct neigh_update_work *update_work;
212 struct neigh_parms *p;
213 struct neighbour *n;
214 bool found = false;
215
216 switch (event) {
217 case NETEVENT_NEIGH_UPDATE:
218 n = ptr;
219#if IS_ENABLED(CONFIG_IPV6)
220 if (n->tbl != ipv6_stub->nd_tbl && n->tbl != &arp_tbl)
221#else
222 if (n->tbl != &arp_tbl)
223#endif
224 return NOTIFY_DONE;
225
226 update_work = mlx5e_alloc_neigh_update_work(priv, n);
227 if (!update_work)
228 return NOTIFY_DONE;
229
230 queue_work(wq: priv->wq, work: &update_work->work);
231 break;
232
233 case NETEVENT_DELAY_PROBE_TIME_UPDATE:
234 p = ptr;
235
236 /* We check the device is present since we don't care about
237 * changes in the default table, we only care about changes
238 * done per device delay prob time parameter.
239 */
240#if IS_ENABLED(CONFIG_IPV6)
241 if (!p->dev || (p->tbl != ipv6_stub->nd_tbl && p->tbl != &arp_tbl))
242#else
243 if (!p->dev || p->tbl != &arp_tbl)
244#endif
245 return NOTIFY_DONE;
246
247 rcu_read_lock();
248 list_for_each_entry_rcu(nhe, &neigh_update->neigh_list,
249 neigh_list) {
250 if (p->dev == READ_ONCE(nhe->neigh_dev)) {
251 found = true;
252 break;
253 }
254 }
255 rcu_read_unlock();
256 if (!found)
257 return NOTIFY_DONE;
258
259 neigh_update->min_interval = min_t(unsigned long,
260 NEIGH_VAR(p, DELAY_PROBE_TIME),
261 neigh_update->min_interval);
262 mlx5_fc_update_sampling_interval(dev: priv->mdev,
263 interval: neigh_update->min_interval);
264 break;
265 }
266 return NOTIFY_DONE;
267}
268
269static const struct rhashtable_params mlx5e_neigh_ht_params = {
270 .head_offset = offsetof(struct mlx5e_neigh_hash_entry, rhash_node),
271 .key_offset = offsetof(struct mlx5e_neigh_hash_entry, m_neigh),
272 .key_len = sizeof(struct mlx5e_neigh),
273 .automatic_shrinking = true,
274};
275
276int mlx5e_rep_neigh_init(struct mlx5e_rep_priv *rpriv)
277{
278 struct mlx5e_neigh_update_table *neigh_update = &rpriv->neigh_update;
279 int err;
280
281 err = rhashtable_init(&neigh_update->neigh_ht, &mlx5e_neigh_ht_params);
282 if (err)
283 goto out_err;
284
285 INIT_LIST_HEAD(list: &neigh_update->neigh_list);
286 mutex_init(&neigh_update->encap_lock);
287 INIT_DELAYED_WORK(&neigh_update->neigh_stats_work,
288 mlx5e_rep_neigh_stats_work);
289 mlx5e_rep_neigh_update_init_interval(rpriv);
290
291 neigh_update->netevent_nb.notifier_call = mlx5e_rep_netevent_event;
292 err = register_netevent_notifier(nb: &neigh_update->netevent_nb);
293 if (err)
294 goto out_notifier;
295 return 0;
296
297out_notifier:
298 neigh_update->netevent_nb.notifier_call = NULL;
299 rhashtable_destroy(ht: &neigh_update->neigh_ht);
300out_err:
301 netdev_warn(dev: rpriv->netdev,
302 format: "Failed to initialize neighbours handling for vport %d\n",
303 rpriv->rep->vport);
304 return err;
305}
306
307void mlx5e_rep_neigh_cleanup(struct mlx5e_rep_priv *rpriv)
308{
309 struct mlx5e_neigh_update_table *neigh_update = &rpriv->neigh_update;
310 struct mlx5e_priv *priv = netdev_priv(dev: rpriv->netdev);
311
312 if (!rpriv->neigh_update.netevent_nb.notifier_call)
313 return;
314
315 unregister_netevent_notifier(nb: &neigh_update->netevent_nb);
316
317 flush_workqueue(priv->wq); /* flush neigh update works */
318
319 cancel_delayed_work_sync(dwork: &rpriv->neigh_update.neigh_stats_work);
320
321 mutex_destroy(lock: &neigh_update->encap_lock);
322 rhashtable_destroy(ht: &neigh_update->neigh_ht);
323}
324
325static int mlx5e_rep_neigh_entry_insert(struct mlx5e_priv *priv,
326 struct mlx5e_neigh_hash_entry *nhe)
327{
328 struct mlx5e_rep_priv *rpriv = priv->ppriv;
329 int err;
330
331 err = rhashtable_insert_fast(ht: &rpriv->neigh_update.neigh_ht,
332 obj: &nhe->rhash_node,
333 params: mlx5e_neigh_ht_params);
334 if (err)
335 return err;
336
337 list_add_rcu(new: &nhe->neigh_list, head: &rpriv->neigh_update.neigh_list);
338
339 return err;
340}
341
342static void mlx5e_rep_neigh_entry_remove(struct mlx5e_neigh_hash_entry *nhe)
343{
344 struct mlx5e_rep_priv *rpriv = nhe->priv->ppriv;
345
346 mutex_lock(&rpriv->neigh_update.encap_lock);
347
348 list_del_rcu(entry: &nhe->neigh_list);
349
350 rhashtable_remove_fast(ht: &rpriv->neigh_update.neigh_ht,
351 obj: &nhe->rhash_node,
352 params: mlx5e_neigh_ht_params);
353 mutex_unlock(lock: &rpriv->neigh_update.encap_lock);
354}
355
356/* This function must only be called under the representor's encap_lock or
357 * inside rcu read lock section.
358 */
359struct mlx5e_neigh_hash_entry *
360mlx5e_rep_neigh_entry_lookup(struct mlx5e_priv *priv,
361 struct mlx5e_neigh *m_neigh)
362{
363 struct mlx5e_rep_priv *rpriv = priv->ppriv;
364 struct mlx5e_neigh_update_table *neigh_update = &rpriv->neigh_update;
365 struct mlx5e_neigh_hash_entry *nhe;
366
367 nhe = rhashtable_lookup_fast(ht: &neigh_update->neigh_ht, key: m_neigh,
368 params: mlx5e_neigh_ht_params);
369 return nhe && mlx5e_rep_neigh_entry_hold(nhe) ? nhe : NULL;
370}
371
372int mlx5e_rep_neigh_entry_create(struct mlx5e_priv *priv,
373 struct mlx5e_neigh *m_neigh,
374 struct net_device *neigh_dev,
375 struct mlx5e_neigh_hash_entry **nhe)
376{
377 int err;
378
379 *nhe = kzalloc(sizeof(**nhe), GFP_KERNEL);
380 if (!*nhe)
381 return -ENOMEM;
382
383 (*nhe)->priv = priv;
384 memcpy(&(*nhe)->m_neigh, m_neigh, sizeof(*m_neigh));
385 spin_lock_init(&(*nhe)->encap_list_lock);
386 INIT_LIST_HEAD(list: &(*nhe)->encap_list);
387 refcount_set(r: &(*nhe)->refcnt, n: 1);
388 WRITE_ONCE((*nhe)->neigh_dev, neigh_dev);
389
390 err = mlx5e_rep_neigh_entry_insert(priv, nhe: *nhe);
391 if (err)
392 goto out_free;
393 return 0;
394
395out_free:
396 kfree(objp: *nhe);
397 return err;
398}
399

source code of linux/drivers/net/ethernet/mellanox/mlx5/core/en/rep/neigh.c