xref: /linux/net/dsa/switch.c (revision 666ed8bfd1de3b091cf32ca03b651757dd86cfff)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Handling of a single switch chip, part of a switch fabric
4  *
5  * Copyright (c) 2017 Savoir-faire Linux Inc.
6  *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
7  */
8 
9 #include <linux/if_bridge.h>
10 #include <linux/netdevice.h>
11 #include <linux/notifier.h>
12 #include <linux/if_vlan.h>
13 #include <net/switchdev.h>
14 
15 #include "dsa_priv.h"
16 
17 static unsigned int dsa_switch_fastest_ageing_time(struct dsa_switch *ds,
18 						   unsigned int ageing_time)
19 {
20 	int i;
21 
22 	for (i = 0; i < ds->num_ports; ++i) {
23 		struct dsa_port *dp = dsa_to_port(ds, i);
24 
25 		if (dp->ageing_time && dp->ageing_time < ageing_time)
26 			ageing_time = dp->ageing_time;
27 	}
28 
29 	return ageing_time;
30 }
31 
32 static int dsa_switch_ageing_time(struct dsa_switch *ds,
33 				  struct dsa_notifier_ageing_time_info *info)
34 {
35 	unsigned int ageing_time = info->ageing_time;
36 	struct switchdev_trans *trans = info->trans;
37 
38 	if (switchdev_trans_ph_prepare(trans)) {
39 		if (ds->ageing_time_min && ageing_time < ds->ageing_time_min)
40 			return -ERANGE;
41 		if (ds->ageing_time_max && ageing_time > ds->ageing_time_max)
42 			return -ERANGE;
43 		return 0;
44 	}
45 
46 	/* Program the fastest ageing time in case of multiple bridges */
47 	ageing_time = dsa_switch_fastest_ageing_time(ds, ageing_time);
48 
49 	if (ds->ops->set_ageing_time)
50 		return ds->ops->set_ageing_time(ds, ageing_time);
51 
52 	return 0;
53 }
54 
55 static bool dsa_switch_mtu_match(struct dsa_switch *ds, int port,
56 				 struct dsa_notifier_mtu_info *info)
57 {
58 	if (ds->index == info->sw_index)
59 		return (port == info->port) || dsa_is_dsa_port(ds, port);
60 
61 	if (!info->propagate_upstream)
62 		return false;
63 
64 	if (dsa_is_dsa_port(ds, port) || dsa_is_cpu_port(ds, port))
65 		return true;
66 
67 	return false;
68 }
69 
70 static int dsa_switch_mtu(struct dsa_switch *ds,
71 			  struct dsa_notifier_mtu_info *info)
72 {
73 	int port, ret;
74 
75 	if (!ds->ops->port_change_mtu)
76 		return -EOPNOTSUPP;
77 
78 	for (port = 0; port < ds->num_ports; port++) {
79 		if (dsa_switch_mtu_match(ds, port, info)) {
80 			ret = ds->ops->port_change_mtu(ds, port, info->mtu);
81 			if (ret)
82 				return ret;
83 		}
84 	}
85 
86 	return 0;
87 }
88 
89 static int dsa_switch_bridge_join(struct dsa_switch *ds,
90 				  struct dsa_notifier_bridge_info *info)
91 {
92 	if (ds->index == info->sw_index && ds->ops->port_bridge_join)
93 		return ds->ops->port_bridge_join(ds, info->port, info->br);
94 
95 	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_join)
96 		return ds->ops->crosschip_bridge_join(ds, info->sw_index,
97 						      info->port, info->br);
98 
99 	return 0;
100 }
101 
102 static int dsa_switch_bridge_leave(struct dsa_switch *ds,
103 				   struct dsa_notifier_bridge_info *info)
104 {
105 	bool unset_vlan_filtering = br_vlan_enabled(info->br);
106 	int err, i;
107 
108 	if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
109 		ds->ops->port_bridge_leave(ds, info->port, info->br);
110 
111 	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_leave)
112 		ds->ops->crosschip_bridge_leave(ds, info->sw_index, info->port,
113 						info->br);
114 
115 	/* If the bridge was vlan_filtering, the bridge core doesn't trigger an
116 	 * event for changing vlan_filtering setting upon slave ports leaving
117 	 * it. That is a good thing, because that lets us handle it and also
118 	 * handle the case where the switch's vlan_filtering setting is global
119 	 * (not per port). When that happens, the correct moment to trigger the
120 	 * vlan_filtering callback is only when the last port left this bridge.
121 	 */
122 	if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
123 		for (i = 0; i < ds->num_ports; i++) {
124 			if (i == info->port)
125 				continue;
126 			if (dsa_to_port(ds, i)->bridge_dev == info->br) {
127 				unset_vlan_filtering = false;
128 				break;
129 			}
130 		}
131 	}
132 	if (unset_vlan_filtering) {
133 		struct switchdev_trans trans = {0};
134 
135 		err = dsa_port_vlan_filtering(dsa_to_port(ds, info->port),
136 					      false, &trans);
137 		if (err && err != EOPNOTSUPP)
138 			return err;
139 	}
140 	return 0;
141 }
142 
143 static int dsa_switch_fdb_add(struct dsa_switch *ds,
144 			      struct dsa_notifier_fdb_info *info)
145 {
146 	int port = dsa_towards_port(ds, info->sw_index, info->port);
147 
148 	if (!ds->ops->port_fdb_add)
149 		return -EOPNOTSUPP;
150 
151 	return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
152 }
153 
154 static int dsa_switch_fdb_del(struct dsa_switch *ds,
155 			      struct dsa_notifier_fdb_info *info)
156 {
157 	int port = dsa_towards_port(ds, info->sw_index, info->port);
158 
159 	if (!ds->ops->port_fdb_del)
160 		return -EOPNOTSUPP;
161 
162 	return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
163 }
164 
165 static bool dsa_switch_mdb_match(struct dsa_switch *ds, int port,
166 				 struct dsa_notifier_mdb_info *info)
167 {
168 	if (ds->index == info->sw_index && port == info->port)
169 		return true;
170 
171 	if (dsa_is_dsa_port(ds, port))
172 		return true;
173 
174 	return false;
175 }
176 
177 static int dsa_switch_mdb_prepare(struct dsa_switch *ds,
178 				  struct dsa_notifier_mdb_info *info)
179 {
180 	int port, err;
181 
182 	if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
183 		return -EOPNOTSUPP;
184 
185 	for (port = 0; port < ds->num_ports; port++) {
186 		if (dsa_switch_mdb_match(ds, port, info)) {
187 			err = ds->ops->port_mdb_prepare(ds, port, info->mdb);
188 			if (err)
189 				return err;
190 		}
191 	}
192 
193 	return 0;
194 }
195 
196 static int dsa_switch_mdb_add(struct dsa_switch *ds,
197 			      struct dsa_notifier_mdb_info *info)
198 {
199 	int port;
200 
201 	if (switchdev_trans_ph_prepare(info->trans))
202 		return dsa_switch_mdb_prepare(ds, info);
203 
204 	if (!ds->ops->port_mdb_add)
205 		return 0;
206 
207 	for (port = 0; port < ds->num_ports; port++)
208 		if (dsa_switch_mdb_match(ds, port, info))
209 			ds->ops->port_mdb_add(ds, port, info->mdb);
210 
211 	return 0;
212 }
213 
214 static int dsa_switch_mdb_del(struct dsa_switch *ds,
215 			      struct dsa_notifier_mdb_info *info)
216 {
217 	if (!ds->ops->port_mdb_del)
218 		return -EOPNOTSUPP;
219 
220 	if (ds->index == info->sw_index)
221 		return ds->ops->port_mdb_del(ds, info->port, info->mdb);
222 
223 	return 0;
224 }
225 
226 static int dsa_port_vlan_device_check(struct net_device *vlan_dev,
227 				      int vlan_dev_vid,
228 				      void *arg)
229 {
230 	struct switchdev_obj_port_vlan *vlan = arg;
231 	u16 vid;
232 
233 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
234 		if (vid == vlan_dev_vid)
235 			return -EBUSY;
236 	}
237 
238 	return 0;
239 }
240 
241 static int dsa_port_vlan_check(struct dsa_switch *ds, int port,
242 			       const struct switchdev_obj_port_vlan *vlan)
243 {
244 	const struct dsa_port *dp = dsa_to_port(ds, port);
245 	int err = 0;
246 
247 	/* Device is not bridged, let it proceed with the VLAN device
248 	 * creation.
249 	 */
250 	if (!dp->bridge_dev)
251 		return err;
252 
253 	/* dsa_slave_vlan_rx_{add,kill}_vid() cannot use the prepare phase and
254 	 * already checks whether there is an overlapping bridge VLAN entry
255 	 * with the same VID, so here we only need to check that if we are
256 	 * adding a bridge VLAN entry there is not an overlapping VLAN device
257 	 * claiming that VID.
258 	 */
259 	return vlan_for_each(dp->slave, dsa_port_vlan_device_check,
260 			     (void *)vlan);
261 }
262 
263 static bool dsa_switch_vlan_match(struct dsa_switch *ds, int port,
264 				  struct dsa_notifier_vlan_info *info)
265 {
266 	if (ds->index == info->sw_index && port == info->port)
267 		return true;
268 
269 	if (dsa_is_dsa_port(ds, port))
270 		return true;
271 
272 	return false;
273 }
274 
275 static int dsa_switch_vlan_prepare(struct dsa_switch *ds,
276 				   struct dsa_notifier_vlan_info *info)
277 {
278 	int port, err;
279 
280 	if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
281 		return -EOPNOTSUPP;
282 
283 	for (port = 0; port < ds->num_ports; port++) {
284 		if (dsa_switch_vlan_match(ds, port, info)) {
285 			err = dsa_port_vlan_check(ds, port, info->vlan);
286 			if (err)
287 				return err;
288 
289 			err = ds->ops->port_vlan_prepare(ds, port, info->vlan);
290 			if (err)
291 				return err;
292 		}
293 	}
294 
295 	return 0;
296 }
297 
298 static int dsa_switch_vlan_add(struct dsa_switch *ds,
299 			       struct dsa_notifier_vlan_info *info)
300 {
301 	int port;
302 
303 	if (switchdev_trans_ph_prepare(info->trans))
304 		return dsa_switch_vlan_prepare(ds, info);
305 
306 	if (!ds->ops->port_vlan_add)
307 		return 0;
308 
309 	for (port = 0; port < ds->num_ports; port++)
310 		if (dsa_switch_vlan_match(ds, port, info))
311 			ds->ops->port_vlan_add(ds, port, info->vlan);
312 
313 	return 0;
314 }
315 
316 static int dsa_switch_vlan_del(struct dsa_switch *ds,
317 			       struct dsa_notifier_vlan_info *info)
318 {
319 	if (!ds->ops->port_vlan_del)
320 		return -EOPNOTSUPP;
321 
322 	if (ds->index == info->sw_index)
323 		return ds->ops->port_vlan_del(ds, info->port, info->vlan);
324 
325 	/* Do not deprogram the DSA links as they may be used as conduit
326 	 * for other VLAN members in the fabric.
327 	 */
328 	return 0;
329 }
330 
331 static int dsa_switch_event(struct notifier_block *nb,
332 			    unsigned long event, void *info)
333 {
334 	struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
335 	int err;
336 
337 	switch (event) {
338 	case DSA_NOTIFIER_AGEING_TIME:
339 		err = dsa_switch_ageing_time(ds, info);
340 		break;
341 	case DSA_NOTIFIER_BRIDGE_JOIN:
342 		err = dsa_switch_bridge_join(ds, info);
343 		break;
344 	case DSA_NOTIFIER_BRIDGE_LEAVE:
345 		err = dsa_switch_bridge_leave(ds, info);
346 		break;
347 	case DSA_NOTIFIER_FDB_ADD:
348 		err = dsa_switch_fdb_add(ds, info);
349 		break;
350 	case DSA_NOTIFIER_FDB_DEL:
351 		err = dsa_switch_fdb_del(ds, info);
352 		break;
353 	case DSA_NOTIFIER_MDB_ADD:
354 		err = dsa_switch_mdb_add(ds, info);
355 		break;
356 	case DSA_NOTIFIER_MDB_DEL:
357 		err = dsa_switch_mdb_del(ds, info);
358 		break;
359 	case DSA_NOTIFIER_VLAN_ADD:
360 		err = dsa_switch_vlan_add(ds, info);
361 		break;
362 	case DSA_NOTIFIER_VLAN_DEL:
363 		err = dsa_switch_vlan_del(ds, info);
364 		break;
365 	case DSA_NOTIFIER_MTU:
366 		err = dsa_switch_mtu(ds, info);
367 		break;
368 	default:
369 		err = -EOPNOTSUPP;
370 		break;
371 	}
372 
373 	/* Non-switchdev operations cannot be rolled back. If a DSA driver
374 	 * returns an error during the chained call, switch chips may be in an
375 	 * inconsistent state.
376 	 */
377 	if (err)
378 		dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
379 			event, err);
380 
381 	return notifier_from_errno(err);
382 }
383 
384 int dsa_switch_register_notifier(struct dsa_switch *ds)
385 {
386 	ds->nb.notifier_call = dsa_switch_event;
387 
388 	return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
389 }
390 
391 void dsa_switch_unregister_notifier(struct dsa_switch *ds)
392 {
393 	int err;
394 
395 	err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
396 	if (err)
397 		dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
398 }
399