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 const struct brport_attribute brport_attr_##_name = {           \
  31         .attr = {.name = __stringify(_name),                    \
  32                  .mode = _mode },                               \
  33         .show   = _show,                                        \
  34         .store  = _store,                                       \
  35 };
  36
  37 #define BRPORT_ATTR_FLAG(_name, _mask)                          \
  38 static ssize_t show_##_name(struct net_bridge_port *p, char *buf) \
  39 {                                                               \
  40         return sprintf(buf, "%d\n", !!(p->flags & _mask));      \
  41 }                                                               \
  42 static int store_##_name(struct net_bridge_port *p, unsigned long v) \
  43 {                                                               \
  44         return store_flag(p, v, _mask);                         \
  45 }                                                               \
  46 static BRPORT_ATTR(_name, S_IRUGO | S_IWUSR,                    \
  47                    show_##_name, store_##_name)
  48
  49 static int store_flag(struct net_bridge_port *p, unsigned long v,
  50                       unsigned long mask)
  51 {
  52         unsigned long flags = p->flags;
  53
  54         if (v)
  55                 flags |= mask;
  56         else
  57                 flags &= ~mask;
  58
  59         if (flags != p->flags) {
  60                 p->flags = flags;
  61                 br_ifinfo_notify(RTM_NEWLINK, p);
  62         }
  63         return 0;
  64 }
  65
  66 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
  67 {
  68         return sprintf(buf, "%d\n", p->path_cost);
  69 }
  70
  71 static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
  72                    show_path_cost, br_stp_set_path_cost);
  73
  74 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
  75 {
  76         return sprintf(buf, "%d\n", p->priority);
  77 }
  78
  79 static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
  80                          show_priority, br_stp_set_port_priority);
  81
  82 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
  83 {
  84         return br_show_bridge_id(buf, &p->designated_root);
  85 }
  86 static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
  87
  88 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
  89 {
  90         return br_show_bridge_id(buf, &p->designated_bridge);
  91 }
  92 static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
  93
  94 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
  95 {
  96         return sprintf(buf, "%d\n", p->designated_port);
  97 }
  98 static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
  99
 100 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
 101 {
 102         return sprintf(buf, "%d\n", p->designated_cost);
 103 }
 104 static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
 105
 106 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
 107 {
 108         return sprintf(buf, "0x%x\n", p->port_id);
 109 }
 110 static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
 111
 112 static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
 113 {
 114         return sprintf(buf, "0x%x\n", p->port_no);
 115 }
 116
 117 static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
 118
 119 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
 120 {
 121         return sprintf(buf, "%d\n", p->topology_change_ack);
 122 }
 123 static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
 124
 125 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
 126 {
 127         return sprintf(buf, "%d\n", p->config_pending);
 128 }
 129 static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
 130
 131 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
 132 {
 133         return sprintf(buf, "%d\n", p->state);
 134 }
 135 static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
 136
 137 static ssize_t show_message_age_timer(struct net_bridge_port *p,
 138                                             char *buf)
 139 {
 140         return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
 141 }
 142 static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
 143
 144 static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
 145                                             char *buf)
 146 {
 147         return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
 148 }
 149 static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
 150
 151 static ssize_t show_hold_timer(struct net_bridge_port *p,
 152                                             char *buf)
 153 {
 154         return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
 155 }
 156 static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
 157
 158 static int store_flush(struct net_bridge_port *p, unsigned long v)
 159 {
 160         br_fdb_delete_by_port(p->br, p, 0); // Don't delete local entry
 161         return 0;
 162 }
 163 static BRPORT_ATTR(flush, S_IWUSR, NULL, store_flush);
 164
 165 BRPORT_ATTR_FLAG(hairpin_mode, BR_HAIRPIN_MODE);
 166 BRPORT_ATTR_FLAG(bpdu_guard, BR_BPDU_GUARD);
 167 BRPORT_ATTR_FLAG(root_block, BR_ROOT_BLOCK);
 168 BRPORT_ATTR_FLAG(learning, BR_LEARNING);
 169 BRPORT_ATTR_FLAG(unicast_flood, BR_FLOOD);
 170
 171 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 172 static ssize_t show_multicast_router(struct net_bridge_port *p, char *buf)
 173 {
 174         return sprintf(buf, "%d\n", p->multicast_router);
 175 }
 176
 177 static int store_multicast_router(struct net_bridge_port *p,
 178                                       unsigned long v)
 179 {
 180         return br_multicast_set_port_router(p, v);
 181 }
 182 static BRPORT_ATTR(multicast_router, S_IRUGO | S_IWUSR, show_multicast_router,
 183                    store_multicast_router);
 184
 185 BRPORT_ATTR_FLAG(multicast_fast_leave, BR_MULTICAST_FAST_LEAVE);
 186 #endif
 187
 188 static const struct brport_attribute *brport_attrs[] = {
 189         &brport_attr_path_cost,
 190         &brport_attr_priority,
 191         &brport_attr_port_id,
 192         &brport_attr_port_no,
 193         &brport_attr_designated_root,
 194         &brport_attr_designated_bridge,
 195         &brport_attr_designated_port,
 196         &brport_attr_designated_cost,
 197         &brport_attr_state,
 198         &brport_attr_change_ack,
 199         &brport_attr_config_pending,
 200         &brport_attr_message_age_timer,
 201         &brport_attr_forward_delay_timer,
 202         &brport_attr_hold_timer,
 203         &brport_attr_flush,
 204         &brport_attr_hairpin_mode,
 205         &brport_attr_bpdu_guard,
 206         &brport_attr_root_block,
 207         &brport_attr_learning,
 208         &brport_attr_unicast_flood,
 209 #ifdef CONFIG_BRIDGE_IGMP_SNOOPING
 210         &brport_attr_multicast_router,
 211         &brport_attr_multicast_fast_leave,
 212 #endif
 213         NULL
 214 };
 215
 216 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 217 #define to_brport(obj)  container_of(obj, struct net_bridge_port, kobj)
 218
 219 static ssize_t brport_show(struct kobject *kobj,
 220                            struct attribute *attr, char *buf)
 221 {
 222         struct brport_attribute *brport_attr = to_brport_attr(attr);
 223         struct net_bridge_port *p = to_brport(kobj);
 224
 225         return brport_attr->show(p, buf);
 226 }
 227
 228 static ssize_t brport_store(struct kobject *kobj,
 229                             struct attribute *attr,
 230                             const char *buf, size_t count)
 231 {
 232         struct brport_attribute *brport_attr = to_brport_attr(attr);
 233         struct net_bridge_port *p = to_brport(kobj);
 234         ssize_t ret = -EINVAL;
 235         char *endp;
 236         unsigned long val;
 237
 238         if (!ns_capable(dev_net(p->dev)->user_ns, CAP_NET_ADMIN))
 239                 return -EPERM;
 240
 241         val = simple_strtoul(buf, &endp, 0);
 242         if (endp != buf) {
 243                 if (!rtnl_trylock())
 244                         return restart_syscall();
 245                 if (p->dev && p->br && brport_attr->store) {
 246                         spin_lock_bh(&p->br->lock);
 247                         ret = brport_attr->store(p, val);
 248                         spin_unlock_bh(&p->br->lock);
 249                         if (ret == 0)
 250                                 ret = count;
 251                 }
 252                 rtnl_unlock();
 253         }
 254         return ret;
 255 }
 256
 257 const struct sysfs_ops brport_sysfs_ops = {
 258         .show = brport_show,
 259         .store = brport_store,
 260 };
 261
 262 /*
 263  * Add sysfs entries to ethernet device added to a bridge.
 264  * Creates a brport subdirectory with bridge attributes.
 265  * Puts symlink in bridge's brif subdirectory
 266  */
 267 int br_sysfs_addif(struct net_bridge_port *p)
 268 {
 269         struct net_bridge *br = p->br;
 270         const struct brport_attribute **a;
 271         int err;
 272
 273         err = sysfs_create_link(&p->kobj, &br->dev->dev.kobj,
 274                                 SYSFS_BRIDGE_PORT_LINK);
 275         if (err)
 276                 return err;
 277
 278         for (a = brport_attrs; *a; ++a) {
 279                 err = sysfs_create_file(&p->kobj, &((*a)->attr));
 280                 if (err)
 281                         return err;
 282         }
 283
 284         strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 285         return sysfs_create_link(br->ifobj, &p->kobj, p->sysfs_name);
 286 }
 287
 288 /* Rename bridge's brif symlink */
 289 int br_sysfs_renameif(struct net_bridge_port *p)
 290 {
 291         struct net_bridge *br = p->br;
 292         int err;
 293
 294         /* If a rename fails, the rollback will cause another
 295          * rename call with the existing name.
 296          */
 297         if (!strncmp(p->sysfs_name, p->dev->name, IFNAMSIZ))
 298                 return 0;
 299
 300         err = sysfs_rename_link(br->ifobj, &p->kobj,
 301                                 p->sysfs_name, p->dev->name);
 302         if (err)
 303                 netdev_notice(br->dev, "unable to rename link %s to %s",
 304                               p->sysfs_name, p->dev->name);
 305         else
 306                 strlcpy(p->sysfs_name, p->dev->name, IFNAMSIZ);
 307
 308         return err;
 309 }