xref: /openbmc/linux/net/dsa/switch.c (revision 95298d63)
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 = {0};
143 
144 		err = dsa_port_vlan_filtering(dsa_to_port(ds, info->port),
145 					      false, &trans);
146 		if (err && err != EOPNOTSUPP)
147 			return err;
148 	}
149 	return 0;
150 }
151 
152 static int dsa_switch_fdb_add(struct dsa_switch *ds,
153 			      struct dsa_notifier_fdb_info *info)
154 {
155 	int port = dsa_towards_port(ds, info->sw_index, info->port);
156 
157 	if (!ds->ops->port_fdb_add)
158 		return -EOPNOTSUPP;
159 
160 	return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
161 }
162 
163 static int dsa_switch_fdb_del(struct dsa_switch *ds,
164 			      struct dsa_notifier_fdb_info *info)
165 {
166 	int port = dsa_towards_port(ds, info->sw_index, info->port);
167 
168 	if (!ds->ops->port_fdb_del)
169 		return -EOPNOTSUPP;
170 
171 	return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
172 }
173 
174 static bool dsa_switch_mdb_match(struct dsa_switch *ds, int port,
175 				 struct dsa_notifier_mdb_info *info)
176 {
177 	if (ds->index == info->sw_index && port == info->port)
178 		return true;
179 
180 	if (dsa_is_dsa_port(ds, port))
181 		return true;
182 
183 	return false;
184 }
185 
186 static int dsa_switch_mdb_prepare(struct dsa_switch *ds,
187 				  struct dsa_notifier_mdb_info *info)
188 {
189 	int port, err;
190 
191 	if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
192 		return -EOPNOTSUPP;
193 
194 	for (port = 0; port < ds->num_ports; port++) {
195 		if (dsa_switch_mdb_match(ds, port, info)) {
196 			err = ds->ops->port_mdb_prepare(ds, port, info->mdb);
197 			if (err)
198 				return err;
199 		}
200 	}
201 
202 	return 0;
203 }
204 
205 static int dsa_switch_mdb_add(struct dsa_switch *ds,
206 			      struct dsa_notifier_mdb_info *info)
207 {
208 	int port;
209 
210 	if (switchdev_trans_ph_prepare(info->trans))
211 		return dsa_switch_mdb_prepare(ds, info);
212 
213 	if (!ds->ops->port_mdb_add)
214 		return 0;
215 
216 	for (port = 0; port < ds->num_ports; port++)
217 		if (dsa_switch_mdb_match(ds, port, info))
218 			ds->ops->port_mdb_add(ds, port, info->mdb);
219 
220 	return 0;
221 }
222 
223 static int dsa_switch_mdb_del(struct dsa_switch *ds,
224 			      struct dsa_notifier_mdb_info *info)
225 {
226 	if (!ds->ops->port_mdb_del)
227 		return -EOPNOTSUPP;
228 
229 	if (ds->index == info->sw_index)
230 		return ds->ops->port_mdb_del(ds, info->port, info->mdb);
231 
232 	return 0;
233 }
234 
235 static int dsa_port_vlan_device_check(struct net_device *vlan_dev,
236 				      int vlan_dev_vid,
237 				      void *arg)
238 {
239 	struct switchdev_obj_port_vlan *vlan = arg;
240 	u16 vid;
241 
242 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
243 		if (vid == vlan_dev_vid)
244 			return -EBUSY;
245 	}
246 
247 	return 0;
248 }
249 
250 static int dsa_port_vlan_check(struct dsa_switch *ds, int port,
251 			       const struct switchdev_obj_port_vlan *vlan)
252 {
253 	const struct dsa_port *dp = dsa_to_port(ds, port);
254 	int err = 0;
255 
256 	/* Device is not bridged, let it proceed with the VLAN device
257 	 * creation.
258 	 */
259 	if (!dp->bridge_dev)
260 		return err;
261 
262 	/* dsa_slave_vlan_rx_{add,kill}_vid() cannot use the prepare phase and
263 	 * already checks whether there is an overlapping bridge VLAN entry
264 	 * with the same VID, so here we only need to check that if we are
265 	 * adding a bridge VLAN entry there is not an overlapping VLAN device
266 	 * claiming that VID.
267 	 */
268 	return vlan_for_each(dp->slave, dsa_port_vlan_device_check,
269 			     (void *)vlan);
270 }
271 
272 static bool dsa_switch_vlan_match(struct dsa_switch *ds, int port,
273 				  struct dsa_notifier_vlan_info *info)
274 {
275 	if (ds->index == info->sw_index && port == info->port)
276 		return true;
277 
278 	if (dsa_is_dsa_port(ds, port))
279 		return true;
280 
281 	return false;
282 }
283 
284 static int dsa_switch_vlan_prepare(struct dsa_switch *ds,
285 				   struct dsa_notifier_vlan_info *info)
286 {
287 	int port, err;
288 
289 	if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
290 		return -EOPNOTSUPP;
291 
292 	for (port = 0; port < ds->num_ports; port++) {
293 		if (dsa_switch_vlan_match(ds, port, info)) {
294 			err = dsa_port_vlan_check(ds, port, info->vlan);
295 			if (err)
296 				return err;
297 
298 			err = ds->ops->port_vlan_prepare(ds, port, info->vlan);
299 			if (err)
300 				return err;
301 		}
302 	}
303 
304 	return 0;
305 }
306 
307 static int dsa_switch_vlan_add(struct dsa_switch *ds,
308 			       struct dsa_notifier_vlan_info *info)
309 {
310 	int port;
311 
312 	if (switchdev_trans_ph_prepare(info->trans))
313 		return dsa_switch_vlan_prepare(ds, info);
314 
315 	if (!ds->ops->port_vlan_add)
316 		return 0;
317 
318 	for (port = 0; port < ds->num_ports; port++)
319 		if (dsa_switch_vlan_match(ds, port, info))
320 			ds->ops->port_vlan_add(ds, port, info->vlan);
321 
322 	return 0;
323 }
324 
325 static int dsa_switch_vlan_del(struct dsa_switch *ds,
326 			       struct dsa_notifier_vlan_info *info)
327 {
328 	if (!ds->ops->port_vlan_del)
329 		return -EOPNOTSUPP;
330 
331 	if (ds->index == info->sw_index)
332 		return ds->ops->port_vlan_del(ds, info->port, info->vlan);
333 
334 	/* Do not deprogram the DSA links as they may be used as conduit
335 	 * for other VLAN members in the fabric.
336 	 */
337 	return 0;
338 }
339 
340 static int dsa_switch_event(struct notifier_block *nb,
341 			    unsigned long event, void *info)
342 {
343 	struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
344 	int err;
345 
346 	switch (event) {
347 	case DSA_NOTIFIER_AGEING_TIME:
348 		err = dsa_switch_ageing_time(ds, info);
349 		break;
350 	case DSA_NOTIFIER_BRIDGE_JOIN:
351 		err = dsa_switch_bridge_join(ds, info);
352 		break;
353 	case DSA_NOTIFIER_BRIDGE_LEAVE:
354 		err = dsa_switch_bridge_leave(ds, info);
355 		break;
356 	case DSA_NOTIFIER_FDB_ADD:
357 		err = dsa_switch_fdb_add(ds, info);
358 		break;
359 	case DSA_NOTIFIER_FDB_DEL:
360 		err = dsa_switch_fdb_del(ds, info);
361 		break;
362 	case DSA_NOTIFIER_MDB_ADD:
363 		err = dsa_switch_mdb_add(ds, info);
364 		break;
365 	case DSA_NOTIFIER_MDB_DEL:
366 		err = dsa_switch_mdb_del(ds, info);
367 		break;
368 	case DSA_NOTIFIER_VLAN_ADD:
369 		err = dsa_switch_vlan_add(ds, info);
370 		break;
371 	case DSA_NOTIFIER_VLAN_DEL:
372 		err = dsa_switch_vlan_del(ds, info);
373 		break;
374 	case DSA_NOTIFIER_MTU:
375 		err = dsa_switch_mtu(ds, info);
376 		break;
377 	default:
378 		err = -EOPNOTSUPP;
379 		break;
380 	}
381 
382 	/* Non-switchdev operations cannot be rolled back. If a DSA driver
383 	 * returns an error during the chained call, switch chips may be in an
384 	 * inconsistent state.
385 	 */
386 	if (err)
387 		dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
388 			event, err);
389 
390 	return notifier_from_errno(err);
391 }
392 
393 int dsa_switch_register_notifier(struct dsa_switch *ds)
394 {
395 	ds->nb.notifier_call = dsa_switch_event;
396 
397 	return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
398 }
399 
400 void dsa_switch_unregister_notifier(struct dsa_switch *ds)
401 {
402 	int err;
403 
404 	err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
405 	if (err)
406 		dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
407 }
408