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