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/kernel.h>
  15 #include <linux/netdevice.h>
  16 #include <linux/if_bridge.h>
  17 #include <linux/rtnetlink.h>
  18 #include <linux/spinlock.h>
  19
  20 #include "br_private.h"
  21
  22 struct brport_attribute {
  23         struct attribute        attr;
  24         ssize_t (*show)(struct net_bridge_port *, char *);
  25         ssize_t (*store)(struct net_bridge_port *, unsigned long);
  26 };
  27
  28 #define BRPORT_ATTR(_name,_mode,_show,_store)                   \
  29 struct brport_attribute brport_attr_##_name = {                 \
  30         .attr = {.name = __stringify(_name),                    \
  31                  .mode = _mode,                                 \
  32                  .owner = THIS_MODULE, },                       \
  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 static ssize_t store_path_cost(struct net_bridge_port *p, unsigned long v)
  42 {
  43         br_stp_set_path_cost(p, v);
  44         return 0;
  45 }
  46 static BRPORT_ATTR(path_cost, S_IRUGO | S_IWUSR,
  47                    show_path_cost, store_path_cost);
  48
  49 static ssize_t show_priority(struct net_bridge_port *p, char *buf)
  50 {
  51         return sprintf(buf, "%d\n", p->priority);
  52 }
  53 static ssize_t store_priority(struct net_bridge_port *p, unsigned long v)
  54 {
  55         if (v >= (1<<(16-BR_PORT_BITS)))
  56                 return -ERANGE;
  57         br_stp_set_port_priority(p, v);
  58         return 0;
  59 }
  60 static BRPORT_ATTR(priority, S_IRUGO | S_IWUSR,
  61                          show_priority, store_priority);
  62
  63 static ssize_t show_designated_root(struct net_bridge_port *p, char *buf)
  64 {
  65         return br_show_bridge_id(buf, &p->designated_root);
  66 }
  67 static BRPORT_ATTR(designated_root, S_IRUGO, show_designated_root, NULL);
  68
  69 static ssize_t show_designated_bridge(struct net_bridge_port *p, char *buf)
  70 {
  71         return br_show_bridge_id(buf, &p->designated_bridge);
  72 }
  73 static BRPORT_ATTR(designated_bridge, S_IRUGO, show_designated_bridge, NULL);
  74
  75 static ssize_t show_designated_port(struct net_bridge_port *p, char *buf)
  76 {
  77         return sprintf(buf, "%d\n", p->designated_port);
  78 }
  79 static BRPORT_ATTR(designated_port, S_IRUGO, show_designated_port, NULL);
  80
  81 static ssize_t show_designated_cost(struct net_bridge_port *p, char *buf)
  82 {
  83         return sprintf(buf, "%d\n", p->designated_cost);
  84 }
  85 static BRPORT_ATTR(designated_cost, S_IRUGO, show_designated_cost, NULL);
  86
  87 static ssize_t show_port_id(struct net_bridge_port *p, char *buf)
  88 {
  89         return sprintf(buf, "0x%x\n", p->port_id);
  90 }
  91 static BRPORT_ATTR(port_id, S_IRUGO, show_port_id, NULL);
  92
  93 static ssize_t show_port_no(struct net_bridge_port *p, char *buf)
  94 {
  95         return sprintf(buf, "0x%x\n", p->port_no);
  96 }
  97
  98 static BRPORT_ATTR(port_no, S_IRUGO, show_port_no, NULL);
  99
 100 static ssize_t show_change_ack(struct net_bridge_port *p, char *buf)
 101 {
 102         return sprintf(buf, "%d\n", p->topology_change_ack);
 103 }
 104 static BRPORT_ATTR(change_ack, S_IRUGO, show_change_ack, NULL);
 105
 106 static ssize_t show_config_pending(struct net_bridge_port *p, char *buf)
 107 {
 108         return sprintf(buf, "%d\n", p->config_pending);
 109 }
 110 static BRPORT_ATTR(config_pending, S_IRUGO, show_config_pending, NULL);
 111
 112 static ssize_t show_port_state(struct net_bridge_port *p, char *buf)
 113 {
 114         return sprintf(buf, "%d\n", p->state);
 115 }
 116 static BRPORT_ATTR(state, S_IRUGO, show_port_state, NULL);
 117
 118 static ssize_t show_message_age_timer(struct net_bridge_port *p,
 119                                             char *buf)
 120 {
 121         return sprintf(buf, "%ld\n", br_timer_value(&p->message_age_timer));
 122 }
 123 static BRPORT_ATTR(message_age_timer, S_IRUGO, show_message_age_timer, NULL);
 124
 125 static ssize_t show_forward_delay_timer(struct net_bridge_port *p,
 126                                             char *buf)
 127 {
 128         return sprintf(buf, "%ld\n", br_timer_value(&p->forward_delay_timer));
 129 }
 130 static BRPORT_ATTR(forward_delay_timer, S_IRUGO, show_forward_delay_timer, NULL);
 131
 132 static ssize_t show_hold_timer(struct net_bridge_port *p,
 133                                             char *buf)
 134 {
 135         return sprintf(buf, "%ld\n", br_timer_value(&p->hold_timer));
 136 }
 137 static BRPORT_ATTR(hold_timer, S_IRUGO, show_hold_timer, NULL);
 138
 139 static struct brport_attribute *brport_attrs[] = {
 140         &brport_attr_path_cost,
 141         &brport_attr_priority,
 142         &brport_attr_port_id,
 143         &brport_attr_port_no,
 144         &brport_attr_designated_root,
 145         &brport_attr_designated_bridge,
 146         &brport_attr_designated_port,
 147         &brport_attr_designated_cost,
 148         &brport_attr_state,
 149         &brport_attr_change_ack,
 150         &brport_attr_config_pending,
 151         &brport_attr_message_age_timer,
 152         &brport_attr_forward_delay_timer,
 153         &brport_attr_hold_timer,
 154         NULL
 155 };
 156
 157 #define to_brport_attr(_at) container_of(_at, struct brport_attribute, attr)
 158 #define to_brport(obj)  container_of(obj, struct net_bridge_port, kobj)
 159
 160 static ssize_t brport_show(struct kobject * kobj,
 161                            struct attribute * attr, char * buf)
 162 {
 163         struct brport_attribute * brport_attr = to_brport_attr(attr);
 164         struct net_bridge_port * p = to_brport(kobj);
 165
 166         return brport_attr->show(p, buf);
 167 }
 168
 169 static ssize_t brport_store(struct kobject * kobj,
 170                             struct attribute * attr,
 171                             const char * buf, size_t count)
 172 {
 173         struct brport_attribute * brport_attr = to_brport_attr(attr);
 174         struct net_bridge_port * p = to_brport(kobj);
 175         ssize_t ret = -EINVAL;
 176         char *endp;
 177         unsigned long val;
 178
 179         if (!capable(CAP_NET_ADMIN))
 180                 return -EPERM;
 181
 182         val = simple_strtoul(buf, &endp, 0);
 183         if (endp != buf) {
 184                 rtnl_lock();
 185                 if (p->dev && p->br && brport_attr->store) {
 186                         spin_lock_bh(&p->br->lock);
 187                         ret = brport_attr->store(p, val);
 188                         spin_unlock_bh(&p->br->lock);
 189                         if (ret == 0)
 190                                 ret = count;
 191                 }
 192                 rtnl_unlock();
 193         }
 194         return ret;
 195 }
 196
 197 /* called from kobject_put when port ref count goes to zero. */
 198 static void brport_release(struct kobject *kobj)
 199 {
 200         kfree(container_of(kobj, struct net_bridge_port, kobj));
 201 }
 202
 203 static struct sysfs_ops brport_sysfs_ops = {
 204         .show = brport_show,
 205         .store = brport_store,
 206 };
 207
 208 static struct kobj_type brport_ktype = {
 209         .sysfs_ops = &brport_sysfs_ops,
 210         .release = brport_release,
 211 };
 212
 213
 214 /*
 215  * Add sysfs entries to ethernet device added to a bridge.
 216  * Creates a brport subdirectory with bridge attributes.
 217  * Puts symlink in bridge's brport subdirectory
 218  */
 219 int br_sysfs_addif(struct net_bridge_port *p)
 220 {
 221         struct net_bridge *br = p->br;
 222         struct brport_attribute **a;
 223         int err;
 224
 225         ASSERT_RTNL();
 226
 227         kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR);
 228         p->kobj.ktype = &brport_ktype;
 229         p->kobj.parent = &(p->dev->class_dev.kobj);
 230         p->kobj.kset = NULL;
 231
 232         err = kobject_add(&p->kobj);
 233         if(err)
 234                 goto out1;
 235
 236         err = sysfs_create_link(&p->kobj, &br->dev->class_dev.kobj,
 237                                 SYSFS_BRIDGE_PORT_LINK);
 238         if (err)
 239                 goto out2;
 240
 241         for (a = brport_attrs; *a; ++a) {
 242                 err = sysfs_create_file(&p->kobj, &((*a)->attr));
 243                 if (err)
 244                         goto out2;
 245         }
 246
 247         err = sysfs_create_link(&br->ifobj, &p->kobj, p->dev->name);
 248         if (err)
 249                 goto out2;
 250
 251         kobject_hotplug(&p->kobj, KOBJ_ADD);
 252         return 0;
 253  out2:
 254         kobject_del(&p->kobj);
 255  out1:
 256         return err;
 257 }
 258
 259 void br_sysfs_removeif(struct net_bridge_port *p)
 260 {
 261         pr_debug("br_sysfs_removeif\n");
 262         sysfs_remove_link(&p->br->ifobj, p->dev->name);
 263         kobject_hotplug(&p->kobj, KOBJ_REMOVE);
 264         kobject_del(&p->kobj);
 265 }
 266
 267 void br_sysfs_freeif(struct net_bridge_port *p)
 268 {
 269         pr_debug("br_sysfs_freeif\n");
 270         kobject_put(&p->kobj);
 271 }