net/bridge/br_sysfs_if.c

   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
  23 struct 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)                   \
  30 struct brport_attribute brport_attr_##_name = {                 \
  31         .attr = {.name = __stringify(_name),                    \
  32                  .mode = _mode },                               \
  33         .show   = _show,                                        \
  34         .store  = _store,                                       \
  35 };
  36
  37 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
  38 {
  39         return sprintf(buf, "%d\n", p->path_cost);
  40 }
  41
  42 static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
  43                    show_path_cost, br_stp_set_path_cost);
  44
  45 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
  46 {
  47         return sprintf(buf, "%d\n", p->priority);
  48 }
  49
  50 static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
  51                          show_priority, br_stp_set_port_priority);
  52
  53 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
  54 {
  55         return br_show_bridge_id(buf, &p->designated_root);
  56 }
  57 static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
  58
  59 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
  60 {
  61         return br_show_bridge_id(buf, &p->designated_bridge);
  62 }
  63 static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
  64
  65 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
  66 {
  67         return sprintf(buf, "%d\n", p->designated_port);
  68 }
  69 static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
  70
  71 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
  72 {
  73         return sprintf(buf, "%d\n", p->designated_cost);
  74 }
  75 static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
  76
  77 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
  78 {
  79         return sprintf(buf, "0x%x\n", p->port_id);
  80 }
  81 static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
  82
  83 static 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
  88 static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
  89
  90 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
  91 {
  92         return sprintf(buf, "%d\n", p->topology_change_ack);
  93 }
  94 static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
  95
  96 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
  97 {
  98         return sprintf(buf, "%d\n", p->config_pending);
  99 }
 100 static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
 101
 102 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
 103 {
 104         return sprintf(buf, "%d\n", p->state);
 105 }
 106 static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
 107
 108 static 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 }
 113 static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
 114
 115 static 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 }
 120 static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
 121
 122 static 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 }
 127 static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
 128
 129 static 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 }
 134 static BRPORT_ATTR(flush, S_IWUSR, NULL, store_flush);
 135
 136 static 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 }
 141 static 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 }
 149 static BRPORT_ATTR(hairpin_mode, S_IRUGO | S_IWUSR,
 150                    show_hairpin_mode, store_hairpin_mode);
 151
 152 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 153 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
 154 {
 155         return sprintf(buf, "%d\n", p->multicast_router);
 156 }
 157
 158 static int store_multicast_router(struct net_bridge_port *p,
 159                                       unsigned long v)
 160 {
 161         return br_multicast_set_port_router(p, v);
 162 }
 163 static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
 164                    store_multicast_router);
 165 #endif
 166
 167 static 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
 193 static 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
 202 static 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
 231 const 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  */
 241 int 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 */
 263 int 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 }