xref: /openbmc/linux/net/dsa/switch.c (revision cb1aaebe)
1 /*
2  * Handling of a single switch chip, part of a switch fabric
3  *
4  * Copyright (c) 2017 Savoir-faire Linux Inc.
5  *	Vivien Didelot <vivien.didelot@savoirfairelinux.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  */
12 
13 #include <linux/if_bridge.h>
14 #include <linux/netdevice.h>
15 #include <linux/notifier.h>
16 #include <linux/if_vlan.h>
17 #include <net/switchdev.h>
18 
19 #include "dsa_priv.h"
20 
21 static unsigned int dsa_switch_fastest_ageing_time(struct dsa_switch *ds,
22 						   unsigned int ageing_time)
23 {
24 	int i;
25 
26 	for (i = 0; i < ds->num_ports; ++i) {
27 		struct dsa_port *dp = &ds->ports[i];
28 
29 		if (dp->ageing_time && dp->ageing_time < ageing_time)
30 			ageing_time = dp->ageing_time;
31 	}
32 
33 	return ageing_time;
34 }
35 
36 static int dsa_switch_ageing_time(struct dsa_switch *ds,
37 				  struct dsa_notifier_ageing_time_info *info)
38 {
39 	unsigned int ageing_time = info->ageing_time;
40 	struct switchdev_trans *trans = info->trans;
41 
42 	if (switchdev_trans_ph_prepare(trans)) {
43 		if (ds->ageing_time_min && ageing_time < ds->ageing_time_min)
44 			return -ERANGE;
45 		if (ds->ageing_time_max && ageing_time > ds->ageing_time_max)
46 			return -ERANGE;
47 		return 0;
48 	}
49 
50 	/* Program the fastest ageing time in case of multiple bridges */
51 	ageing_time = dsa_switch_fastest_ageing_time(ds, ageing_time);
52 
53 	if (ds->ops->set_ageing_time)
54 		return ds->ops->set_ageing_time(ds, ageing_time);
55 
56 	return 0;
57 }
58 
59 static int dsa_switch_bridge_join(struct dsa_switch *ds,
60 				  struct dsa_notifier_bridge_info *info)
61 {
62 	if (ds->index == info->sw_index && ds->ops->port_bridge_join)
63 		return ds->ops->port_bridge_join(ds, info->port, info->br);
64 
65 	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_join)
66 		return ds->ops->crosschip_bridge_join(ds, info->sw_index,
67 						      info->port, info->br);
68 
69 	return 0;
70 }
71 
72 static int dsa_switch_bridge_leave(struct dsa_switch *ds,
73 				   struct dsa_notifier_bridge_info *info)
74 {
75 	bool unset_vlan_filtering = br_vlan_enabled(info->br);
76 	int err, i;
77 
78 	if (ds->index == info->sw_index && ds->ops->port_bridge_leave)
79 		ds->ops->port_bridge_leave(ds, info->port, info->br);
80 
81 	if (ds->index != info->sw_index && ds->ops->crosschip_bridge_leave)
82 		ds->ops->crosschip_bridge_leave(ds, info->sw_index, info->port,
83 						info->br);
84 
85 	/* If the bridge was vlan_filtering, the bridge core doesn't trigger an
86 	 * event for changing vlan_filtering setting upon slave ports leaving
87 	 * it. That is a good thing, because that lets us handle it and also
88 	 * handle the case where the switch's vlan_filtering setting is global
89 	 * (not per port). When that happens, the correct moment to trigger the
90 	 * vlan_filtering callback is only when the last port left this bridge.
91 	 */
92 	if (unset_vlan_filtering && ds->vlan_filtering_is_global) {
93 		for (i = 0; i < ds->num_ports; i++) {
94 			if (i == info->port)
95 				continue;
96 			if (dsa_to_port(ds, i)->bridge_dev == info->br) {
97 				unset_vlan_filtering = false;
98 				break;
99 			}
100 		}
101 	}
102 	if (unset_vlan_filtering) {
103 		struct switchdev_trans trans = {0};
104 
105 		err = dsa_port_vlan_filtering(&ds->ports[info->port],
106 					      false, &trans);
107 		if (err && err != EOPNOTSUPP)
108 			return err;
109 	}
110 	return 0;
111 }
112 
113 static int dsa_switch_fdb_add(struct dsa_switch *ds,
114 			      struct dsa_notifier_fdb_info *info)
115 {
116 	int port = dsa_towards_port(ds, info->sw_index, info->port);
117 
118 	if (!ds->ops->port_fdb_add)
119 		return -EOPNOTSUPP;
120 
121 	return ds->ops->port_fdb_add(ds, port, info->addr, info->vid);
122 }
123 
124 static int dsa_switch_fdb_del(struct dsa_switch *ds,
125 			      struct dsa_notifier_fdb_info *info)
126 {
127 	int port = dsa_towards_port(ds, info->sw_index, info->port);
128 
129 	if (!ds->ops->port_fdb_del)
130 		return -EOPNOTSUPP;
131 
132 	return ds->ops->port_fdb_del(ds, port, info->addr, info->vid);
133 }
134 
135 static int
136 dsa_switch_mdb_prepare_bitmap(struct dsa_switch *ds,
137 			      const struct switchdev_obj_port_mdb *mdb,
138 			      const unsigned long *bitmap)
139 {
140 	int port, err;
141 
142 	if (!ds->ops->port_mdb_prepare || !ds->ops->port_mdb_add)
143 		return -EOPNOTSUPP;
144 
145 	for_each_set_bit(port, bitmap, ds->num_ports) {
146 		err = ds->ops->port_mdb_prepare(ds, port, mdb);
147 		if (err)
148 			return err;
149 	}
150 
151 	return 0;
152 }
153 
154 static void dsa_switch_mdb_add_bitmap(struct dsa_switch *ds,
155 				      const struct switchdev_obj_port_mdb *mdb,
156 				      const unsigned long *bitmap)
157 {
158 	int port;
159 
160 	for_each_set_bit(port, bitmap, ds->num_ports)
161 		ds->ops->port_mdb_add(ds, port, mdb);
162 }
163 
164 static int dsa_switch_mdb_add(struct dsa_switch *ds,
165 			      struct dsa_notifier_mdb_info *info)
166 {
167 	const struct switchdev_obj_port_mdb *mdb = info->mdb;
168 	struct switchdev_trans *trans = info->trans;
169 	int port;
170 
171 	/* Build a mask of Multicast group members */
172 	bitmap_zero(ds->bitmap, ds->num_ports);
173 	if (ds->index == info->sw_index)
174 		set_bit(info->port, ds->bitmap);
175 	for (port = 0; port < ds->num_ports; port++)
176 		if (dsa_is_dsa_port(ds, port))
177 			set_bit(port, ds->bitmap);
178 
179 	if (switchdev_trans_ph_prepare(trans))
180 		return dsa_switch_mdb_prepare_bitmap(ds, mdb, ds->bitmap);
181 
182 	dsa_switch_mdb_add_bitmap(ds, mdb, ds->bitmap);
183 
184 	return 0;
185 }
186 
187 static int dsa_switch_mdb_del(struct dsa_switch *ds,
188 			      struct dsa_notifier_mdb_info *info)
189 {
190 	const struct switchdev_obj_port_mdb *mdb = info->mdb;
191 
192 	if (!ds->ops->port_mdb_del)
193 		return -EOPNOTSUPP;
194 
195 	if (ds->index == info->sw_index)
196 		return ds->ops->port_mdb_del(ds, info->port, mdb);
197 
198 	return 0;
199 }
200 
201 static int dsa_port_vlan_device_check(struct net_device *vlan_dev,
202 				      int vlan_dev_vid,
203 				      void *arg)
204 {
205 	struct switchdev_obj_port_vlan *vlan = arg;
206 	u16 vid;
207 
208 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
209 		if (vid == vlan_dev_vid)
210 			return -EBUSY;
211 	}
212 
213 	return 0;
214 }
215 
216 static int dsa_port_vlan_check(struct dsa_switch *ds, int port,
217 			       const struct switchdev_obj_port_vlan *vlan)
218 {
219 	const struct dsa_port *dp = dsa_to_port(ds, port);
220 	int err = 0;
221 
222 	/* Device is not bridged, let it proceed with the VLAN device
223 	 * creation.
224 	 */
225 	if (!dp->bridge_dev)
226 		return err;
227 
228 	/* dsa_slave_vlan_rx_{add,kill}_vid() cannot use the prepare phase and
229 	 * already checks whether there is an overlapping bridge VLAN entry
230 	 * with the same VID, so here we only need to check that if we are
231 	 * adding a bridge VLAN entry there is not an overlapping VLAN device
232 	 * claiming that VID.
233 	 */
234 	return vlan_for_each(dp->slave, dsa_port_vlan_device_check,
235 			     (void *)vlan);
236 }
237 
238 static int
239 dsa_switch_vlan_prepare_bitmap(struct dsa_switch *ds,
240 			       const struct switchdev_obj_port_vlan *vlan,
241 			       const unsigned long *bitmap)
242 {
243 	int port, err;
244 
245 	if (!ds->ops->port_vlan_prepare || !ds->ops->port_vlan_add)
246 		return -EOPNOTSUPP;
247 
248 	for_each_set_bit(port, bitmap, ds->num_ports) {
249 		err = dsa_port_vlan_check(ds, port, vlan);
250 		if (err)
251 			return err;
252 
253 		err = ds->ops->port_vlan_prepare(ds, port, vlan);
254 		if (err)
255 			return err;
256 	}
257 
258 	return 0;
259 }
260 
261 static void
262 dsa_switch_vlan_add_bitmap(struct dsa_switch *ds,
263 			   const struct switchdev_obj_port_vlan *vlan,
264 			   const unsigned long *bitmap)
265 {
266 	int port;
267 
268 	for_each_set_bit(port, bitmap, ds->num_ports)
269 		ds->ops->port_vlan_add(ds, port, vlan);
270 }
271 
272 static int dsa_switch_vlan_add(struct dsa_switch *ds,
273 			       struct dsa_notifier_vlan_info *info)
274 {
275 	const struct switchdev_obj_port_vlan *vlan = info->vlan;
276 	struct switchdev_trans *trans = info->trans;
277 	int port;
278 
279 	/* Build a mask of VLAN members */
280 	bitmap_zero(ds->bitmap, ds->num_ports);
281 	if (ds->index == info->sw_index)
282 		set_bit(info->port, ds->bitmap);
283 	for (port = 0; port < ds->num_ports; port++)
284 		if (dsa_is_cpu_port(ds, port) || dsa_is_dsa_port(ds, port))
285 			set_bit(port, ds->bitmap);
286 
287 	if (switchdev_trans_ph_prepare(trans))
288 		return dsa_switch_vlan_prepare_bitmap(ds, vlan, ds->bitmap);
289 
290 	dsa_switch_vlan_add_bitmap(ds, vlan, ds->bitmap);
291 
292 	return 0;
293 }
294 
295 static int dsa_switch_vlan_del(struct dsa_switch *ds,
296 			       struct dsa_notifier_vlan_info *info)
297 {
298 	const struct switchdev_obj_port_vlan *vlan = info->vlan;
299 
300 	if (!ds->ops->port_vlan_del)
301 		return -EOPNOTSUPP;
302 
303 	if (ds->index == info->sw_index)
304 		return ds->ops->port_vlan_del(ds, info->port, vlan);
305 
306 	return 0;
307 }
308 
309 static int dsa_switch_event(struct notifier_block *nb,
310 			    unsigned long event, void *info)
311 {
312 	struct dsa_switch *ds = container_of(nb, struct dsa_switch, nb);
313 	int err;
314 
315 	switch (event) {
316 	case DSA_NOTIFIER_AGEING_TIME:
317 		err = dsa_switch_ageing_time(ds, info);
318 		break;
319 	case DSA_NOTIFIER_BRIDGE_JOIN:
320 		err = dsa_switch_bridge_join(ds, info);
321 		break;
322 	case DSA_NOTIFIER_BRIDGE_LEAVE:
323 		err = dsa_switch_bridge_leave(ds, info);
324 		break;
325 	case DSA_NOTIFIER_FDB_ADD:
326 		err = dsa_switch_fdb_add(ds, info);
327 		break;
328 	case DSA_NOTIFIER_FDB_DEL:
329 		err = dsa_switch_fdb_del(ds, info);
330 		break;
331 	case DSA_NOTIFIER_MDB_ADD:
332 		err = dsa_switch_mdb_add(ds, info);
333 		break;
334 	case DSA_NOTIFIER_MDB_DEL:
335 		err = dsa_switch_mdb_del(ds, info);
336 		break;
337 	case DSA_NOTIFIER_VLAN_ADD:
338 		err = dsa_switch_vlan_add(ds, info);
339 		break;
340 	case DSA_NOTIFIER_VLAN_DEL:
341 		err = dsa_switch_vlan_del(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