xref: /openbmc/linux/net/dsa/switch.c (revision 3cea11cd)
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 	struct dsa_switch_tree *dst = ds->dst;
93 
94 	if (dst->index == info->tree_index && ds->index == info->sw_index &&
95 	    ds->ops->port_bridge_join)
96 		return ds->ops->port_bridge_join(ds, info->port, info->br);
97 
98 	if ((dst->index != info->tree_index || ds->index != info->sw_index) &&
99 	    ds->ops->crosschip_bridge_join)
100 		return ds->ops->crosschip_bridge_join(ds, info->tree_index,
101 						      info->sw_index,
102 						      info->port, info->br);
103 
104 	return 0;
105 }
106 
107 static int dsa_switch_bridge_leave(struct dsa_switch *ds,
108 				   struct dsa_notifier_bridge_info *info)
109 {
110 	bool unset_vlan_filtering = br_vlan_enabled(info->br);
111 	struct dsa_switch_tree *dst = ds->dst;
112 	int err, i;
113 
114 	if (dst->index == info->tree_index && ds->index == info->sw_index &&
115 	    ds->ops->port_bridge_join)
116 		ds->ops->port_bridge_leave(ds, info->port, info->br);
117 
118 	if ((dst->index != info->tree_index || ds->index != info->sw_index) &&
119 	    ds->ops->crosschip_bridge_join)
120 		ds->ops->crosschip_bridge_leave(ds, info->tree_index,
121 						info->sw_index, info->port,
122 						info->br);
123 
124 	/* If the bridge was vlan_filtering, the bridge core doesn't trigger an
125 	 * event for changing vlan_filtering setting upon slave ports leaving
126 	 * it. That is a good thing, because that lets us handle it and also
127 	 * handle the case where the switch's vlan_filtering setting is global
128 	 * (not per port). When that happens, the correct moment to trigger the
129 	 * vlan_filtering callback is only when the last port left this bridge.
130 	 */
131 	if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
132 		for (i = 0; i < ds->num_ports; i++) {
133 			if (i == info->port)
134 				continue;
135 			if (dsa_to_port(ds, i)->bridge_dev == info->br) {
136 				unset_vlan_filtering = false;
137 				break;
138 			}
139 		}
140 	}
141 	if (unset_vlan_filtering) {
142 		struct switchdev_trans trans;
143 
144 		trans.ph_prepare = true;
145 		err = dsa_port_vlan_filtering(dsa_to_port(ds, info->port),
146 					      false, &trans);
147 		if (err && err != EOPNOTSUPP)
148 			return err;
149 
150 		trans.ph_prepare = false;
151 		err = dsa_port_vlan_filtering(dsa_to_port(ds, info->port),
152 					      false, &trans);
153 		if (err && err != EOPNOTSUPP)
154 			return err;
155 	}
156 	return 0;
157 }
158 
159 static int dsa_switch_fdb_add(struct dsa_switch *ds,
160 			      struct dsa_notifier_fdb_info *info)
161 {
162 	int port = dsa_towards_port(ds, info->sw_index, info->port);
163 
164 	if (!ds->ops->port_fdb_add)
165 		return -EOPNOTSUPP;
166 
167 	return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
168 }
169 
170 static int dsa_switch_fdb_del(struct dsa_switch *ds,
171 			      struct dsa_notifier_fdb_info *info)
172 {
173 	int port = dsa_towards_port(ds, info->sw_index, info->port);
174 
175 	if (!ds->ops->port_fdb_del)
176 		return -EOPNOTSUPP;
177 
178 	return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
179 }
180 
181 static bool dsa_switch_mdb_match(struct dsa_switch *ds, int port,
182 				 struct dsa_notifier_mdb_info *info)
183 {
184 	if (ds->index == info->sw_index && port == info->port)
185 		return true;
186 
187 	if (dsa_is_dsa_port(ds, port))
188 		return true;
189 
190 	return false;
191 }
192 
193 static int dsa_switch_mdb_prepare(struct dsa_switch *ds,
194 				  struct dsa_notifier_mdb_info *info)
195 {
196 	int port, err;
197 
198 	if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
199 		return -EOPNOTSUPP;
200 
201 	for (port = 0; port < ds->num_ports; port++) {
202 		if (dsa_switch_mdb_match(ds, port, info)) {
203 			err = ds->ops->port_mdb_prepare(ds, port, info->mdb);
204 			if (err)
205 				return err;
206 		}
207 	}
208 
209 	return 0;
210 }
211 
212 static int dsa_switch_mdb_add(struct dsa_switch *ds,
213 			      struct dsa_notifier_mdb_info *info)
214 {
215 	int port;
216 
217 	if (switchdev_trans_ph_prepare(info->trans))
218 		return dsa_switch_mdb_prepare(ds, info);
219 
220 	if (!ds->ops->port_mdb_add)
221 		return 0;
222 
223 	for (port = 0; port < ds->num_ports; port++)
224 		if (dsa_switch_mdb_match(ds, port, info))
225 			ds->ops->port_mdb_add(ds, port, info->mdb);
226 
227 	return 0;
228 }
229 
230 static int dsa_switch_mdb_del(struct dsa_switch *ds,
231 			      struct dsa_notifier_mdb_info *info)
232 {
233 	if (!ds->ops->port_mdb_del)
234 		return -EOPNOTSUPP;
235 
236 	if (ds->index == info->sw_index)
237 		return ds->ops->port_mdb_del(ds, info->port, info->mdb);
238 
239 	return 0;
240 }
241 
242 static bool dsa_switch_vlan_match(struct dsa_switch *ds, int port,
243 				  struct dsa_notifier_vlan_info *info)
244 {
245 	if (ds->index == info->sw_index && port == info->port)
246 		return true;
247 
248 	if (dsa_is_dsa_port(ds, port))
249 		return true;
250 
251 	return false;
252 }
253 
254 static int dsa_switch_vlan_prepare(struct dsa_switch *ds,
255 				   struct dsa_notifier_vlan_info *info)
256 {
257 	int port, err;
258 
259 	if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
260 		return -EOPNOTSUPP;
261 
262 	for (port = 0; port < ds->num_ports; port++) {
263 		if (dsa_switch_vlan_match(ds, port, info)) {
264 			err = ds->ops->port_vlan_prepare(ds, port, info->vlan);
265 			if (err)
266 				return err;
267 		}
268 	}
269 
270 	return 0;
271 }
272 
273 static int dsa_switch_vlan_add(struct dsa_switch *ds,
274 			       struct dsa_notifier_vlan_info *info)
275 {
276 	int port;
277 
278 	if (switchdev_trans_ph_prepare(info->trans))
279 		return dsa_switch_vlan_prepare(ds, info);
280 
281 	if (!ds->ops->port_vlan_add)
282 		return 0;
283 
284 	for (port = 0; port < ds->num_ports; port++)
285 		if (dsa_switch_vlan_match(ds, port, info))
286 			ds->ops->port_vlan_add(ds, port, info->vlan);
287 
288 	return 0;
289 }
290 
291 static int dsa_switch_vlan_del(struct dsa_switch *ds,
292 			       struct dsa_notifier_vlan_info *info)
293 {
294 	if (!ds->ops->port_vlan_del)
295 		return -EOPNOTSUPP;
296 
297 	if (ds->index == info->sw_index)
298 		return ds->ops->port_vlan_del(ds, info->port, info->vlan);
299 
300 	/* Do not deprogram the DSA links as they may be used as conduit
301 	 * for other VLAN members in the fabric.
302 	 */
303 	return 0;
304 }
305 
306 static int dsa_switch_event(struct notifier_block *nb,
307 			    unsigned long event, void *info)
308 {
309 	struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
310 	int err;
311 
312 	switch (event) {
313 	case DSA_NOTIFIER_AGEING_TIME:
314 		err = dsa_switch_ageing_time(ds, info);
315 		break;
316 	case DSA_NOTIFIER_BRIDGE_JOIN:
317 		err = dsa_switch_bridge_join(ds, info);
318 		break;
319 	case DSA_NOTIFIER_BRIDGE_LEAVE:
320 		err = dsa_switch_bridge_leave(ds, info);
321 		break;
322 	case DSA_NOTIFIER_FDB_ADD:
323 		err = dsa_switch_fdb_add(ds, info);
324 		break;
325 	case DSA_NOTIFIER_FDB_DEL:
326 		err = dsa_switch_fdb_del(ds, info);
327 		break;
328 	case DSA_NOTIFIER_MDB_ADD:
329 		err = dsa_switch_mdb_add(ds, info);
330 		break;
331 	case DSA_NOTIFIER_MDB_DEL:
332 		err = dsa_switch_mdb_del(ds, info);
333 		break;
334 	case DSA_NOTIFIER_VLAN_ADD:
335 		err = dsa_switch_vlan_add(ds, info);
336 		break;
337 	case DSA_NOTIFIER_VLAN_DEL:
338 		err = dsa_switch_vlan_del(ds, info);
339 		break;
340 	case DSA_NOTIFIER_MTU:
341 		err = dsa_switch_mtu(ds, info);
342 		break;
343 	default:
344 		err = -EOPNOTSUPP;
345 		break;
346 	}
347 
348 	/* Non-switchdev operations cannot be rolled back. If a DSA driver
349 	 * returns an error during the chained call, switch chips may be in an
350 	 * inconsistent state.
351 	 */
352 	if (err)
353 		dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
354 			event, err);
355 
356 	return notifier_from_errno(err);
357 }
358 
359 int dsa_switch_register_notifier(struct dsa_switch *ds)
360 {
361 	ds->nb.notifier_call = dsa_switch_event;
362 
363 	return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
364 }
365 
366 void dsa_switch_unregister_notifier(struct dsa_switch *ds)
367 {
368 	int err;
369 
370 	err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
371 	if (err)
372 		dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
373 }
374