xref: /openbmc/linux/net/dsa/switch.c (revision c7b03852)
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 = &ds->ports[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 int dsa_switch_bridge_join(struct dsa_switch *ds,
56 				  struct dsa_notifier_bridge_info *info)
57 {
58 	if (ds->index == info->sw_index && ds->ops->port_bridge_join)
59 		return ds->ops->port_bridge_join(ds, info->port, info->br);
60 
61 	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_join)
62 		return ds->ops->crosschip_bridge_join(ds, info->sw_index,
63 						      info->port, info->br);
64 
65 	return 0;
66 }
67 
68 static int dsa_switch_bridge_leave(struct dsa_switch *ds,
69 				   struct dsa_notifier_bridge_info *info)
70 {
71 	bool unset_vlan_filtering = br_vlan_enabled(info->br);
72 	int err, i;
73 
74 	if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
75 		ds->ops->port_bridge_leave(ds, info->port, info->br);
76 
77 	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_leave)
78 		ds->ops->crosschip_bridge_leave(ds, info->sw_index, info->port,
79 						info->br);
80 
81 	/* If the bridge was vlan_filtering, the bridge core doesn't trigger an
82 	 * event for changing vlan_filtering setting upon slave ports leaving
83 	 * it. That is a good thing, because that lets us handle it and also
84 	 * handle the case where the switch's vlan_filtering setting is global
85 	 * (not per port). When that happens, the correct moment to trigger the
86 	 * vlan_filtering callback is only when the last port left this bridge.
87 	 */
88 	if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
89 		for (i = 0; i < ds->num_ports; i++) {
90 			if (i == info->port)
91 				continue;
92 			if (dsa_to_port(ds, i)->bridge_dev == info->br) {
93 				unset_vlan_filtering = false;
94 				break;
95 			}
96 		}
97 	}
98 	if (unset_vlan_filtering) {
99 		struct switchdev_trans trans = {0};
100 
101 		err = dsa_port_vlan_filtering(&ds->ports[info->port],
102 					      false, &trans);
103 		if (err && err != EOPNOTSUPP)
104 			return err;
105 	}
106 	return 0;
107 }
108 
109 static int dsa_switch_fdb_add(struct dsa_switch *ds,
110 			      struct dsa_notifier_fdb_info *info)
111 {
112 	int port = dsa_towards_port(ds, info->sw_index, info->port);
113 
114 	if (!ds->ops->port_fdb_add)
115 		return -EOPNOTSUPP;
116 
117 	return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
118 }
119 
120 static int dsa_switch_fdb_del(struct dsa_switch *ds,
121 			      struct dsa_notifier_fdb_info *info)
122 {
123 	int port = dsa_towards_port(ds, info->sw_index, info->port);
124 
125 	if (!ds->ops->port_fdb_del)
126 		return -EOPNOTSUPP;
127 
128 	return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
129 }
130 
131 static bool dsa_switch_mdb_match(struct dsa_switch *ds, int port,
132 				 struct dsa_notifier_mdb_info *info)
133 {
134 	if (ds->index == info->sw_index && port == info->port)
135 		return true;
136 
137 	if (dsa_is_dsa_port(ds, port))
138 		return true;
139 
140 	return false;
141 }
142 
143 static int dsa_switch_mdb_prepare(struct dsa_switch *ds,
144 				  struct dsa_notifier_mdb_info *info)
145 {
146 	int port, err;
147 
148 	if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
149 		return -EOPNOTSUPP;
150 
151 	for (port = 0; port < ds->num_ports; port++) {
152 		if (dsa_switch_mdb_match(ds, port, info)) {
153 			err = ds->ops->port_mdb_prepare(ds, port, info->mdb);
154 			if (err)
155 				return err;
156 		}
157 	}
158 
159 	return 0;
160 }
161 
162 static int dsa_switch_mdb_add(struct dsa_switch *ds,
163 			      struct dsa_notifier_mdb_info *info)
164 {
165 	int port;
166 
167 	if (switchdev_trans_ph_prepare(info->trans))
168 		return dsa_switch_mdb_prepare(ds, info);
169 
170 	if (!ds->ops->port_mdb_add)
171 		return 0;
172 
173 	for (port = 0; port < ds->num_ports; port++)
174 		if (dsa_switch_mdb_match(ds, port, info))
175 			ds->ops->port_mdb_add(ds, port, info->mdb);
176 
177 	return 0;
178 }
179 
180 static int dsa_switch_mdb_del(struct dsa_switch *ds,
181 			      struct dsa_notifier_mdb_info *info)
182 {
183 	if (!ds->ops->port_mdb_del)
184 		return -EOPNOTSUPP;
185 
186 	if (ds->index == info->sw_index)
187 		return ds->ops->port_mdb_del(ds, info->port, info->mdb);
188 
189 	return 0;
190 }
191 
192 static int dsa_port_vlan_device_check(struct net_device *vlan_dev,
193 				      int vlan_dev_vid,
194 				      void *arg)
195 {
196 	struct switchdev_obj_port_vlan *vlan = arg;
197 	u16 vid;
198 
199 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
200 		if (vid == vlan_dev_vid)
201 			return -EBUSY;
202 	}
203 
204 	return 0;
205 }
206 
207 static int dsa_port_vlan_check(struct dsa_switch *ds, int port,
208 			       const struct switchdev_obj_port_vlan *vlan)
209 {
210 	const struct dsa_port *dp = dsa_to_port(ds, port);
211 	int err = 0;
212 
213 	/* Device is not bridged, let it proceed with the VLAN device
214 	 * creation.
215 	 */
216 	if (!dp->bridge_dev)
217 		return err;
218 
219 	/* dsa_slave_vlan_rx_{add,kill}_vid() cannot use the prepare phase and
220 	 * already checks whether there is an overlapping bridge VLAN entry
221 	 * with the same VID, so here we only need to check that if we are
222 	 * adding a bridge VLAN entry there is not an overlapping VLAN device
223 	 * claiming that VID.
224 	 */
225 	return vlan_for_each(dp->slave, dsa_port_vlan_device_check,
226 			     (void *)vlan);
227 }
228 
229 static bool dsa_switch_vlan_match(struct dsa_switch *ds, int port,
230 				  struct dsa_notifier_vlan_info *info)
231 {
232 	if (ds->index == info->sw_index && port == info->port)
233 		return true;
234 
235 	if (dsa_is_dsa_port(ds, port))
236 		return true;
237 
238 	return false;
239 }
240 
241 static int dsa_switch_vlan_prepare(struct dsa_switch *ds,
242 				   struct dsa_notifier_vlan_info *info)
243 {
244 	int port, err;
245 
246 	if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
247 		return -EOPNOTSUPP;
248 
249 	for (port = 0; port < ds->num_ports; port++) {
250 		if (dsa_switch_vlan_match(ds, port, info)) {
251 			err = dsa_port_vlan_check(ds, port, info->vlan);
252 			if (err)
253 				return err;
254 
255 			err = ds->ops->port_vlan_prepare(ds, port, info->vlan);
256 			if (err)
257 				return err;
258 		}
259 	}
260 
261 	return 0;
262 }
263 
264 static int dsa_switch_vlan_add(struct dsa_switch *ds,
265 			       struct dsa_notifier_vlan_info *info)
266 {
267 	int port;
268 
269 	if (switchdev_trans_ph_prepare(info->trans))
270 		return dsa_switch_vlan_prepare(ds, info);
271 
272 	if (!ds->ops->port_vlan_add)
273 		return 0;
274 
275 	for (port = 0; port < ds->num_ports; port++)
276 		if (dsa_switch_vlan_match(ds, port, info))
277 			ds->ops->port_vlan_add(ds, port, info->vlan);
278 
279 	return 0;
280 }
281 
282 static int dsa_switch_vlan_del(struct dsa_switch *ds,
283 			       struct dsa_notifier_vlan_info *info)
284 {
285 	if (!ds->ops->port_vlan_del)
286 		return -EOPNOTSUPP;
287 
288 	if (ds->index == info->sw_index)
289 		return ds->ops->port_vlan_del(ds, info->port, info->vlan);
290 
291 	/* Do not deprogram the DSA links as they may be used as conduit
292 	 * for other VLAN members in the fabric.
293 	 */
294 	return 0;
295 }
296 
297 static int dsa_switch_event(struct notifier_block *nb,
298 			    unsigned long event, void *info)
299 {
300 	struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
301 	int err;
302 
303 	switch (event) {
304 	case DSA_NOTIFIER_AGEING_TIME:
305 		err = dsa_switch_ageing_time(ds, info);
306 		break;
307 	case DSA_NOTIFIER_BRIDGE_JOIN:
308 		err = dsa_switch_bridge_join(ds, info);
309 		break;
310 	case DSA_NOTIFIER_BRIDGE_LEAVE:
311 		err = dsa_switch_bridge_leave(ds, info);
312 		break;
313 	case DSA_NOTIFIER_FDB_ADD:
314 		err = dsa_switch_fdb_add(ds, info);
315 		break;
316 	case DSA_NOTIFIER_FDB_DEL:
317 		err = dsa_switch_fdb_del(ds, info);
318 		break;
319 	case DSA_NOTIFIER_MDB_ADD:
320 		err = dsa_switch_mdb_add(ds, info);
321 		break;
322 	case DSA_NOTIFIER_MDB_DEL:
323 		err = dsa_switch_mdb_del(ds, info);
324 		break;
325 	case DSA_NOTIFIER_VLAN_ADD:
326 		err = dsa_switch_vlan_add(ds, info);
327 		break;
328 	case DSA_NOTIFIER_VLAN_DEL:
329 		err = dsa_switch_vlan_del(ds, info);
330 		break;
331 	default:
332 		err = -EOPNOTSUPP;
333 		break;
334 	}
335 
336 	/* Non-switchdev operations cannot be rolled back. If a DSA driver
337 	 * returns an error during the chained call, switch chips may be in an
338 	 * inconsistent state.
339 	 */
340 	if (err)
341 		dev_dbg(ds->dev, "breaking chain for DSA event %lu (%d)\n",
342 			event, err);
343 
344 	return notifier_from_errno(err);
345 }
346 
347 int dsa_switch_register_notifier(struct dsa_switch *ds)
348 {
349 	ds->nb.notifier_call = dsa_switch_event;
350 
351 	return raw_notifier_chain_register(&ds->dst->nh, &ds->nb);
352 }
353 
354 void dsa_switch_unregister_notifier(struct dsa_switch *ds)
355 {
356 	int err;
357 
358 	err = raw_notifier_chain_unregister(&ds->dst->nh, &ds->nb);
359 	if (err)
360 		dev_err(ds->dev, "failed to unregister notifier (%d)\n", err);
361 }
362