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v3.1
 
  1/*
  2 *	Sysfs attributes of bridge ports
  3 *	Linux ethernet bridge
  4 *
  5 *	Authors:
  6 *	Stephen Hemminger		<shemminger@osdl.org>
  7 *
  8 *	This program is free software; you can redistribute it and/or
  9 *	modify it under the terms of the GNU General Public License
 10 *	as published by the Free Software Foundation; either version
 11 *	2 of the License, or (at your option) any later version.
 12 */
 13
 14#include <linux/capability.h>
 15#include <linux/kernel.h>
 16#include <linux/netdevice.h>
 17#include <linux/if_bridge.h>
 18#include <linux/rtnetlink.h>
 19#include <linux/spinlock.h>
 
 20
 21#include "br_private.h"
 22
 23struct brport_attribute {
 24	struct attribute	attr;
 25	ssize_t (*show)(struct net_bridge_port *, char *);
 26	int (*store)(struct net_bridge_port *, unsigned long);
 
 
 
 
 
 
 
 
 
 27};
 28
 29#define BRPORT_ATTR(_name,_mode,_show,_store)		        \
 30struct brport_attribute brport_attr_##_name = { 	        \
 31	.attr = {.name = __stringify(_name), 			\
 32		 .mode = _mode },				\
 33	.show	= _show,					\
 34	.store	= _store,					\
 35};
 36
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 37static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
 38{
 39	return sprintf(buf, "%d\n", p->path_cost);
 40}
 41
 42static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
 43		   show_path_cost, br_stp_set_path_cost);
 44
 45static ssize_t show_priority(struct net_bridge_port *p, char *buf)
 46{
 47	return sprintf(buf, "%d\n", p->priority);
 48}
 49
 50static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
 51			 show_priority, br_stp_set_port_priority);
 52
 53static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
 54{
 55	return br_show_bridge_id(buf, &p->designated_root);
 56}
 57static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
 58
 59static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
 60{
 61	return br_show_bridge_id(buf, &p->designated_bridge);
 62}
 63static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
 64
 65static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
 66{
 67	return sprintf(buf, "%d\n", p->designated_port);
 68}
 69static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
 70
 71static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
 72{
 73	return sprintf(buf, "%d\n", p->designated_cost);
 74}
 75static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
 76
 77static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
 78{
 79	return sprintf(buf, "0x%x\n", p->port_id);
 80}
 81static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
 82
 83static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
 84{
 85	return sprintf(buf, "0x%x\n", p->port_no);
 86}
 87
 88static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
 89
 90static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
 91{
 92	return sprintf(buf, "%d\n", p->topology_change_ack);
 93}
 94static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
 95
 96static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
 97{
 98	return sprintf(buf, "%d\n", p->config_pending);
 99}
100static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
101
102static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
103{
104	return sprintf(buf, "%d\n", p->state);
105}
106static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
107
108static ssize_t show_message_age_timer(struct net_bridge_port *p,
109					    char *buf)
110{
111	return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
112}
113static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
114
115static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
116					    char *buf)
117{
118	return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
119}
120static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
121
122static ssize_t show_hold_timer(struct net_bridge_port *p,
123					    char *buf)
124{
125	return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
126}
127static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
128
129static int store_flush(struct net_bridge_port *p, unsigned long v)
130{
131	br_fdb_delete_by_port(p->br, p, 0); // Don't delete local entry
132	return 0;
133}
134static BRPORT_ATTR(flush, S_IWUSR, NULL, store_flush);
135
136static ssize_t show_hairpin_mode(struct net_bridge_port *p, char *buf)
137{
138	int hairpin_mode = (p->flags & BR_HAIRPIN_MODE) ? 1 : 0;
139	return sprintf(buf, "%d\n", hairpin_mode);
140}
141static int store_hairpin_mode(struct net_bridge_port *p, unsigned long v)
 
 
142{
143	if (v)
144		p->flags |= BR_HAIRPIN_MODE;
145	else
146		p->flags &= ~BR_HAIRPIN_MODE;
147	return 0;
148}
149static BRPORT_ATTR(hairpin_mode, S_IRUGO | S_IWUSR,
150		   show_hairpin_mode, store_hairpin_mode);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
151
152#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
153static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
154{
155	return sprintf(buf, "%d\n", p->multicast_router);
156}
157
158static int store_multicast_router(struct net_bridge_port *p,
159				      unsigned long v)
160{
161	return br_multicast_set_port_router(p, v);
162}
163static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
164		   store_multicast_router);
 
 
 
165#endif
166
167static struct brport_attribute *brport_attrs[] = {
168	&brport_attr_path_cost,
169	&brport_attr_priority,
170	&brport_attr_port_id,
171	&brport_attr_port_no,
172	&brport_attr_designated_root,
173	&brport_attr_designated_bridge,
174	&brport_attr_designated_port,
175	&brport_attr_designated_cost,
176	&brport_attr_state,
177	&brport_attr_change_ack,
178	&brport_attr_config_pending,
179	&brport_attr_message_age_timer,
180	&brport_attr_forward_delay_timer,
181	&brport_attr_hold_timer,
182	&brport_attr_flush,
183	&brport_attr_hairpin_mode,
 
 
 
 
184#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
185	&brport_attr_multicast_router,
 
 
186#endif
 
 
 
 
 
 
 
 
187	NULL
188};
189
190#define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
191#define to_brport(obj)	container_of(obj, struct net_bridge_port, kobj)
192
193static ssize_t brport_show(struct kobject * kobj,
194			   struct attribute * attr, char * buf)
195{
196	struct brport_attribute * brport_attr = to_brport_attr(attr);
197	struct net_bridge_port * p = to_brport(kobj);
 
 
 
198
199	return brport_attr->show(p, buf);
200}
201
202static ssize_t brport_store(struct kobject * kobj,
203			    struct attribute * attr,
204			    const char * buf, size_t count)
205{
206	struct brport_attribute * brport_attr = to_brport_attr(attr);
207	struct net_bridge_port * p = to_brport(kobj);
208	ssize_t ret = -EINVAL;
209	char *endp;
210	unsigned long val;
 
211
212	if (!capable(CAP_NET_ADMIN))
213		return -EPERM;
214
215	val = simple_strtoul(buf, &endp, 0);
216	if (endp != buf) {
217		if (!rtnl_trylock())
218			return restart_syscall();
219		if (p->dev && p->br && brport_attr->store) {
220			spin_lock_bh(&p->br->lock);
221			ret = brport_attr->store(p, val);
222			spin_unlock_bh(&p->br->lock);
223			if (ret == 0)
224				ret = count;
225		}
226		rtnl_unlock();
 
 
 
 
 
 
 
 
 
 
227	}
 
 
 
 
 
 
 
 
228	return ret;
229}
230
231const struct sysfs_ops brport_sysfs_ops = {
232	.show = brport_show,
233	.store = brport_store,
234};
235
236/*
237 * Add sysfs entries to ethernet device added to a bridge.
238 * Creates a brport subdirectory with bridge attributes.
239 * Puts symlink in bridge's brif subdirectory
240 */
241int br_sysfs_addif(struct net_bridge_port *p)
242{
243	struct net_bridge *br = p->br;
244	struct brport_attribute **a;
245	int err;
246
247	err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
248				SYSFS_BRIDGE_PORT_LINK);
249	if (err)
250		return err;
251
252	for (a = brport_attrs; *a; ++a) {
253		err = sysfs_create_file(&p->kobj, &((*a)->attr));
254		if (err)
255			return err;
256	}
257
258	strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
259	return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
260}
261
262/* Rename bridge's brif symlink */
263int br_sysfs_renameif(struct net_bridge_port *p)
264{
265	struct net_bridge *br = p->br;
266	int err;
267
268	/* If a rename fails, the rollback will cause another
269	 * rename call with the existing name.
270	 */
271	if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
272		return 0;
273
274	err = sysfs_rename_link(br->ifobj, &p->kobj,
275				p->sysfs_name, p->dev->name);
276	if (err)
277		netdev_notice(br->dev, "unable to rename link %s to %s",
278			      p->sysfs_name, p->dev->name);
279	else
280		strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
281
282	return err;
283}
v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *	Sysfs attributes of bridge ports
  4 *	Linux ethernet bridge
  5 *
  6 *	Authors:
  7 *	Stephen Hemminger		<shemminger@osdl.org>
 
 
 
 
 
  8 */
  9
 10#include <linux/capability.h>
 11#include <linux/kernel.h>
 12#include <linux/netdevice.h>
 13#include <linux/if_bridge.h>
 14#include <linux/rtnetlink.h>
 15#include <linux/spinlock.h>
 16#include <linux/sched/signal.h>
 17
 18#include "br_private.h"
 19
 20struct brport_attribute {
 21	struct attribute	attr;
 22	ssize_t (*show)(struct net_bridge_port *, char *);
 23	int (*store)(struct net_bridge_port *, unsigned long);
 24	int (*store_raw)(struct net_bridge_port *, char *);
 25};
 26
 27#define BRPORT_ATTR_RAW(_name, _mode, _show, _store)			\
 28const struct brport_attribute brport_attr_##_name = {			\
 29	.attr		= {.name = __stringify(_name),			\
 30			   .mode = _mode },				\
 31	.show		= _show,					\
 32	.store_raw	= _store,					\
 33};
 34
 35#define BRPORT_ATTR(_name, _mode, _show, _store)		\
 36const struct brport_attribute brport_attr_##_name = { 	        \
 37	.attr = {.name = __stringify(_name), 			\
 38		 .mode = _mode },				\
 39	.show	= _show,					\
 40	.store	= _store,					\
 41};
 42
 43#define BRPORT_ATTR_FLAG(_name, _mask)				\
 44static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
 45{								\
 46	return sprintf(buf, "%d\n", !!(p->flags & _mask));	\
 47}								\
 48static int store_##_name(struct net_bridge_port *p, unsigned long v) \
 49{								\
 50	return store_flag(p, v, _mask);				\
 51}								\
 52static BRPORT_ATTR(_name, 0644,					\
 53		   show_##_name, store_##_name)
 54
 55static int store_flag(struct net_bridge_port *p, unsigned long v,
 56		      unsigned long mask)
 57{
 58	unsigned long flags;
 59
 60	flags = p->flags;
 61
 62	if (v)
 63		flags |= mask;
 64	else
 65		flags &= ~mask;
 66
 67	if (flags != p->flags) {
 68		p->flags = flags;
 69		br_port_flags_change(p, mask);
 70	}
 71	return 0;
 72}
 73
 74static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
 75{
 76	return sprintf(buf, "%d\n", p->path_cost);
 77}
 78
 79static BRPORT_ATTR(path_cost, 0644,
 80		   show_path_cost, br_stp_set_path_cost);
 81
 82static ssize_t show_priority(struct net_bridge_port *p, char *buf)
 83{
 84	return sprintf(buf, "%d\n", p->priority);
 85}
 86
 87static BRPORT_ATTR(priority, 0644,
 88			 show_priority, br_stp_set_port_priority);
 89
 90static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
 91{
 92	return br_show_bridge_id(buf, &p->designated_root);
 93}
 94static BRPORT_ATTR(designated_root, 0444, show_designated_root, NULL);
 95
 96static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
 97{
 98	return br_show_bridge_id(buf, &p->designated_bridge);
 99}
100static BRPORT_ATTR(designated_bridge, 0444, show_designated_bridge, NULL);
101
102static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
103{
104	return sprintf(buf, "%d\n", p->designated_port);
105}
106static BRPORT_ATTR(designated_port, 0444, show_designated_port, NULL);
107
108static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
109{
110	return sprintf(buf, "%d\n", p->designated_cost);
111}
112static BRPORT_ATTR(designated_cost, 0444, show_designated_cost, NULL);
113
114static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
115{
116	return sprintf(buf, "0x%x\n", p->port_id);
117}
118static BRPORT_ATTR(port_id, 0444, show_port_id, NULL);
119
120static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
121{
122	return sprintf(buf, "0x%x\n", p->port_no);
123}
124
125static BRPORT_ATTR(port_no, 0444, show_port_no, NULL);
126
127static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
128{
129	return sprintf(buf, "%d\n", p->topology_change_ack);
130}
131static BRPORT_ATTR(change_ack, 0444, show_change_ack, NULL);
132
133static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
134{
135	return sprintf(buf, "%d\n", p->config_pending);
136}
137static BRPORT_ATTR(config_pending, 0444, show_config_pending, NULL);
138
139static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
140{
141	return sprintf(buf, "%d\n", p->state);
142}
143static BRPORT_ATTR(state, 0444, show_port_state, NULL);
144
145static ssize_t show_message_age_timer(struct net_bridge_port *p,
146					    char *buf)
147{
148	return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
149}
150static BRPORT_ATTR(message_age_timer, 0444, show_message_age_timer, NULL);
151
152static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
153					    char *buf)
154{
155	return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
156}
157static BRPORT_ATTR(forward_delay_timer, 0444, show_forward_delay_timer, NULL);
158
159static ssize_t show_hold_timer(struct net_bridge_port *p,
160					    char *buf)
161{
162	return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
163}
164static BRPORT_ATTR(hold_timer, 0444, show_hold_timer, NULL);
165
166static int store_flush(struct net_bridge_port *p, unsigned long v)
167{
168	br_fdb_delete_by_port(p->br, p, 0, 0); // Don't delete local entry
169	return 0;
170}
171static BRPORT_ATTR(flush, 0200, NULL, store_flush);
172
173static ssize_t show_group_fwd_mask(struct net_bridge_port *p, char *buf)
174{
175	return sprintf(buf, "%#x\n", p->group_fwd_mask);
 
176}
177
178static int store_group_fwd_mask(struct net_bridge_port *p,
179				unsigned long v)
180{
181	if (v & BR_GROUPFWD_MACPAUSE)
182		return -EINVAL;
183	p->group_fwd_mask = v;
184
185	return 0;
186}
187static BRPORT_ATTR(group_fwd_mask, 0644, show_group_fwd_mask,
188		   store_group_fwd_mask);
189
190static ssize_t show_backup_port(struct net_bridge_port *p, char *buf)
191{
192	struct net_bridge_port *backup_p;
193	int ret = 0;
194
195	rcu_read_lock();
196	backup_p = rcu_dereference(p->backup_port);
197	if (backup_p)
198		ret = sprintf(buf, "%s\n", backup_p->dev->name);
199	rcu_read_unlock();
200
201	return ret;
202}
203
204static int store_backup_port(struct net_bridge_port *p, char *buf)
205{
206	struct net_device *backup_dev = NULL;
207	char *nl = strchr(buf, '\n');
208
209	if (nl)
210		*nl = '\0';
211
212	if (strlen(buf) > 0) {
213		backup_dev = __dev_get_by_name(dev_net(p->dev), buf);
214		if (!backup_dev)
215			return -ENOENT;
216	}
217
218	return nbp_backup_change(p, backup_dev);
219}
220static BRPORT_ATTR_RAW(backup_port, 0644, show_backup_port, store_backup_port);
221
222BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
223BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
224BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
225BRPORT_ATTR_FLAG(learning, BR_LEARNING);
226BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
227BRPORT_ATTR_FLAG(proxyarp, BR_PROXYARP);
228BRPORT_ATTR_FLAG(proxyarp_wifi, BR_PROXYARP_WIFI);
229BRPORT_ATTR_FLAG(multicast_flood, BR_MCAST_FLOOD);
230BRPORT_ATTR_FLAG(broadcast_flood, BR_BCAST_FLOOD);
231BRPORT_ATTR_FLAG(neigh_suppress, BR_NEIGH_SUPPRESS);
232BRPORT_ATTR_FLAG(isolated, BR_ISOLATED);
233
234#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
235static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
236{
237	return sprintf(buf, "%d\n", p->multicast_router);
238}
239
240static int store_multicast_router(struct net_bridge_port *p,
241				      unsigned long v)
242{
243	return br_multicast_set_port_router(p, v);
244}
245static BRPORT_ATTR(multicast_router, 0644, show_multicast_router,
246		   store_multicast_router);
247
248BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
249BRPORT_ATTR_FLAG(multicast_to_unicast, BR_MULTICAST_TO_UNICAST);
250#endif
251
252static const struct brport_attribute *brport_attrs[] = {
253	&brport_attr_path_cost,
254	&brport_attr_priority,
255	&brport_attr_port_id,
256	&brport_attr_port_no,
257	&brport_attr_designated_root,
258	&brport_attr_designated_bridge,
259	&brport_attr_designated_port,
260	&brport_attr_designated_cost,
261	&brport_attr_state,
262	&brport_attr_change_ack,
263	&brport_attr_config_pending,
264	&brport_attr_message_age_timer,
265	&brport_attr_forward_delay_timer,
266	&brport_attr_hold_timer,
267	&brport_attr_flush,
268	&brport_attr_hairpin_mode,
269	&brport_attr_bpdu_guard,
270	&brport_attr_root_block,
271	&brport_attr_learning,
272	&brport_attr_unicast_flood,
273#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
274	&brport_attr_multicast_router,
275	&brport_attr_multicast_fast_leave,
276	&brport_attr_multicast_to_unicast,
277#endif
278	&brport_attr_proxyarp,
279	&brport_attr_proxyarp_wifi,
280	&brport_attr_multicast_flood,
281	&brport_attr_broadcast_flood,
282	&brport_attr_group_fwd_mask,
283	&brport_attr_neigh_suppress,
284	&brport_attr_isolated,
285	&brport_attr_backup_port,
286	NULL
287};
288
289#define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 
290
291static ssize_t brport_show(struct kobject *kobj,
292			   struct attribute *attr, char *buf)
293{
294	struct brport_attribute *brport_attr = to_brport_attr(attr);
295	struct net_bridge_port *p = kobj_to_brport(kobj);
296
297	if (!brport_attr->show)
298		return -EINVAL;
299
300	return brport_attr->show(p, buf);
301}
302
303static ssize_t brport_store(struct kobject *kobj,
304			    struct attribute *attr,
305			    const char *buf, size_t count)
306{
307	struct brport_attribute *brport_attr = to_brport_attr(attr);
308	struct net_bridge_port *p = kobj_to_brport(kobj);
309	ssize_t ret = -EINVAL;
 
310	unsigned long val;
311	char *endp;
312
313	if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
314		return -EPERM;
315
316	if (!rtnl_trylock())
317		return restart_syscall();
318
319	if (brport_attr->store_raw) {
320		char *buf_copy;
321
322		buf_copy = kstrndup(buf, count, GFP_KERNEL);
323		if (!buf_copy) {
324			ret = -ENOMEM;
325			goto out_unlock;
326		}
327		spin_lock_bh(&p->br->lock);
328		ret = brport_attr->store_raw(p, buf_copy);
329		spin_unlock_bh(&p->br->lock);
330		kfree(buf_copy);
331	} else if (brport_attr->store) {
332		val = simple_strtoul(buf, &endp, 0);
333		if (endp == buf)
334			goto out_unlock;
335		spin_lock_bh(&p->br->lock);
336		ret = brport_attr->store(p, val);
337		spin_unlock_bh(&p->br->lock);
338	}
339
340	if (!ret) {
341		br_ifinfo_notify(RTM_NEWLINK, NULL, p);
342		ret = count;
343	}
344out_unlock:
345	rtnl_unlock();
346
347	return ret;
348}
349
350const struct sysfs_ops brport_sysfs_ops = {
351	.show = brport_show,
352	.store = brport_store,
353};
354
355/*
356 * Add sysfs entries to ethernet device added to a bridge.
357 * Creates a brport subdirectory with bridge attributes.
358 * Puts symlink in bridge's brif subdirectory
359 */
360int br_sysfs_addif(struct net_bridge_port *p)
361{
362	struct net_bridge *br = p->br;
363	const struct brport_attribute **a;
364	int err;
365
366	err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
367				SYSFS_BRIDGE_PORT_LINK);
368	if (err)
369		return err;
370
371	for (a = brport_attrs; *a; ++a) {
372		err = sysfs_create_file(&p->kobj, &((*a)->attr));
373		if (err)
374			return err;
375	}
376
377	strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
378	return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
379}
380
381/* Rename bridge's brif symlink */
382int br_sysfs_renameif(struct net_bridge_port *p)
383{
384	struct net_bridge *br = p->br;
385	int err;
386
387	/* If a rename fails, the rollback will cause another
388	 * rename call with the existing name.
389	 */
390	if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
391		return 0;
392
393	err = sysfs_rename_link(br->ifobj, &p->kobj,
394				p->sysfs_name, p->dev->name);
395	if (err)
396		netdev_notice(br->dev, "unable to rename link %s to %s",
397			      p->sysfs_name, p->dev->name);
398	else
399		strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
400
401	return err;
402}