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         ssize_t (*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                  .owner = THIS_MODULE, },                       \
  34         .show   = _show,                                        \
  35         .store  = _store,                                       \
  36 };
  37
  38 static ssize_t show_path_cost(struct net_bridge_port *p, char *buf)
  39 {
  40         return sprintf(buf, "%d\n", p->path_cost);
  41 }
  42 static ssize_t store_path_cost(struct net_bridge_port *p, unsigned long v)
  43 {
  44         br_stp_set_path_cost(p, v);
  45         return 0;
  46 }
  47 static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
  48                    show_path_cost, store_path_cost);
  49
  50 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
  51 {
  52         return sprintf(buf, "%d\n", p->priority);
  53 }
  54 static ssize_t store_priority(struct net_bridge_port *p, unsigned long v)
  55 {
  56         if (v >= (1<<(16-BR_PORT_BITS)))
  57                 return -ERANGE;
  58         br_stp_set_port_priority(p, v);
  59         return 0;
  60 }
  61 static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
  62                          show_priority, store_priority);
  63
  64 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
  65 {
  66         return br_show_bridge_id(buf, &p->designated_root);
  67 }
  68 static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
  69
  70 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
  71 {
  72         return br_show_bridge_id(buf, &p->designated_bridge);
  73 }
  74 static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
  75
  76 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
  77 {
  78         return sprintf(buf, "%d\n", p->designated_port);
  79 }
  80 static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
  81
  82 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
  83 {
  84         return sprintf(buf, "%d\n", p->designated_cost);
  85 }
  86 static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
  87
  88 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
  89 {
  90         return sprintf(buf, "0x%x\n", p->port_id);
  91 }
  92 static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
  93
  94 static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
  95 {
  96         return sprintf(buf, "0x%x\n", p->port_no);
  97 }
  98
  99 static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
 100
 101 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
 102 {
 103         return sprintf(buf, "%d\n", p->topology_change_ack);
 104 }
 105 static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
 106
 107 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
 108 {
 109         return sprintf(buf, "%d\n", p->config_pending);
 110 }
 111 static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
 112
 113 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
 114 {
 115         return sprintf(buf, "%d\n", p->state);
 116 }
 117 static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
 118
 119 static ssize_t show_message_age_timer(struct net_bridge_port *p,
 120                                             char *buf)
 121 {
 122         return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
 123 }
 124 static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
 125
 126 static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
 127                                             char *buf)
 128 {
 129         return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
 130 }
 131 static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
 132
 133 static ssize_t show_hold_timer(struct net_bridge_port *p,
 134                                             char *buf)
 135 {
 136         return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
 137 }
 138 static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
 139
 140 static struct brport_attribute *brport_attrs[] = {
 141         &brport_attr_path_cost,
 142         &brport_attr_priority,
 143         &brport_attr_port_id,
 144         &brport_attr_port_no,
 145         &brport_attr_designated_root,
 146         &brport_attr_designated_bridge,
 147         &brport_attr_designated_port,
 148         &brport_attr_designated_cost,
 149         &brport_attr_state,
 150         &brport_attr_change_ack,
 151         &brport_attr_config_pending,
 152         &brport_attr_message_age_timer,
 153         &brport_attr_forward_delay_timer,
 154         &brport_attr_hold_timer,
 155         NULL
 156 };
 157
 158 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 159 #define to_brport(obj)  container_of(obj, struct net_bridge_port, kobj)
 160
 161 static ssize_t brport_show(struct kobject * kobj,
 162                            struct attribute * attr, char * buf)
 163 {
 164         struct brport_attribute * brport_attr = to_brport_attr(attr);
 165         struct net_bridge_port * p = to_brport(kobj);
 166
 167         return brport_attr->show(p, buf);
 168 }
 169
 170 static ssize_t brport_store(struct kobject * kobj,
 171                             struct attribute * attr,
 172                             const char * buf, size_t count)
 173 {
 174         struct brport_attribute * brport_attr = to_brport_attr(attr);
 175         struct net_bridge_port * p = to_brport(kobj);
 176         ssize_t ret = -EINVAL;
 177         char *endp;
 178         unsigned long val;
 179
 180         if (!capable(CAP_NET_ADMIN))
 181                 return -EPERM;
 182
 183         val = simple_strtoul(buf, &endp, 0);
 184         if (endp != buf) {
 185                 rtnl_lock();
 186                 if (p->dev && p->br && brport_attr->store) {
 187                         spin_lock_bh(&p->br->lock);
 188                         ret = brport_attr->store(p, val);
 189                         spin_unlock_bh(&p->br->lock);
 190                         if (ret == 0)
 191                                 ret = count;
 192                 }
 193                 rtnl_unlock();
 194         }
 195         return ret;
 196 }
 197
 198 /* called from kobject_put when port ref count goes to zero. */
 199 static void brport_release(struct kobject *kobj)
 200 {
 201         kfree(container_of(kobj, struct net_bridge_port, kobj));
 202 }
 203
 204 static struct sysfs_ops brport_sysfs_ops = {
 205         .show = brport_show,
 206         .store = brport_store,
 207 };
 208
 209 static struct kobj_type brport_ktype = {
 210         .sysfs_ops = &brport_sysfs_ops,
 211         .release = brport_release,
 212 };
 213
 214
 215 /*
 216  * Add sysfs entries to ethernet device added to a bridge.
 217  * Creates a brport subdirectory with bridge attributes.
 218  * Puts symlink in bridge's brport subdirectory
 219  */
 220 int br_sysfs_addif(struct net_bridge_port *p)
 221 {
 222         struct net_bridge *br = p->br;
 223         struct brport_attribute **a;
 224         int err;
 225
 226         ASSERT_RTNL();
 227
 228         kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR);
 229         p->kobj.ktype = &brport_ktype;
 230         p->kobj.parent = &(p->dev->class_dev.kobj);
 231         p->kobj.kset = NULL;
 232
 233         err = kobject_add(&p->kobj);
 234         if(err)
 235                 goto out1;
 236
 237         err = sysfs_create_link(&p->kobj, &br->dev->class_dev.kobj,
 238                                 SYSFS_BRIDGE_PORT_LINK);
 239         if (err)
 240                 goto out2;
 241
 242         for (a = brport_attrs; *a; ++a) {
 243                 err = sysfs_create_file(&p->kobj, &((*a)->attr));
 244                 if (err)
 245                         goto out2;
 246         }
 247
 248         err = sysfs_create_link(&br->ifobj, &p->kobj, p->dev->name);
 249         if (err)
 250                 goto out2;
 251
 252         kobject_uevent(&p->kobj, KOBJ_ADD);
 253         return 0;
 254  out2:
 255         kobject_del(&p->kobj);
 256  out1:
 257         return err;
 258 }
 259
 260 void br_sysfs_removeif(struct net_bridge_port *p)
 261 {
 262         pr_debug("br_sysfs_removeif\n");
 263         sysfs_remove_link(&p->br->ifobj, p->dev->name);
 264         kobject_uevent(&p->kobj, KOBJ_REMOVE);
 265         kobject_del(&p->kobj);
 266 }
 267
 268 void br_sysfs_freeif(struct net_bridge_port *p)
 269 {
 270         pr_debug("br_sysfs_freeif\n");
 271         kobject_put(&p->kobj);
 272 }