/*
* This is the linux wireless configuration interface.
*
* Copyright 2006, 2007 Johannes Berg <johannes@sipsolutions.net>
*/
#include <linux/if.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/nl80211.h>
#include <linux/debugfs.h>
#include <linux/notifier.h>
#include <linux/device.h>
#include <net/genetlink.h>
#include <net/cfg80211.h>
#include <net/wireless.h>
#include "nl80211.h"
#include "core.h"
#include "sysfs.h"
/* name for sysfs, %d is appended */
#define PHY_NAME "phy"
MODULE_AUTHOR("Johannes Berg");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("wireless configuration support");
/* RCU might be appropriate here since we usually
* only read the list, and that can happen quite
* often because we need to do it for each command */
LIST_HEAD(cfg80211_drv_list);
DEFINE_MUTEX(cfg80211_drv_mutex);
static int wiphy_counter;
/* for debugfs */
static struct dentry *ieee80211_debugfs_dir;
/* requires cfg80211_drv_mutex to be held! */
static struct cfg80211_registered_device *cfg80211_drv_by_wiphy(int wiphy)
{
struct cfg80211_registered_device *result = NULL, *drv;
list_for_each_entry(drv, &cfg80211_drv_list, list) {
if (drv->idx == wiphy) {
result = drv;
break;
}
}
return result;
}
/* requires cfg80211_drv_mutex to be held! */
static struct cfg80211_registered_device *
__cfg80211_drv_from_info(struct genl_info *info)
{
int ifindex;
struct cfg80211_registered_device *bywiphy = NULL, *byifidx = NULL;
struct net_device *dev;
int err = -EINVAL;
if (info->attrs[NL80211_ATTR_WIPHY]) {
bywiphy = cfg80211_drv_by_wiphy(
nla_get_u32(info->attrs[NL80211_ATTR_WIPHY]));
err = -ENODEV;
}
if (info->attrs[NL80211_ATTR_IFINDEX]) {
ifindex = nla_get_u32(info->attrs[NL80211_ATTR_IFINDEX]);
dev = dev_get_by_index(&init_net, ifindex);
if (dev) {
if (dev->ieee80211_ptr)
byifidx =
wiphy_to_dev(dev->ieee80211_ptr->wiphy);
dev_put(dev);
}
err = -ENODEV;
}
if (bywiphy && byifidx) {
if (bywiphy != byifidx)
return ERR_PTR(-EINVAL);
else
return bywiphy; /* == byifidx */
}
if (bywiphy)
return bywiphy;
if (byifidx)
return byifidx;
return ERR_PTR(err);
}
struct cfg80211_registered_device *
cfg80211_get_dev_from_info(struct genl_info *info)
{
struct cfg80211_registered_device *drv;
mutex_lock(&cfg80211_drv_mutex);
drv = __cfg80211_drv_from_info(info);
/* if it is not an error we grab the lock on
* it to assure it won't be going away while
* we operate on it */
if (!IS_ERR(drv))
mutex_lock(&drv->mtx);
mutex_unlock(&cfg80211_drv_mutex);
return drv;
}
struct cfg80211_registered_device *
cfg80211_get_dev_from_ifindex(int ifindex)
{
struct cfg80211_registered_device *drv = ERR_PTR(-ENODEV);
struct net_device *dev;
mutex_lock(&cfg80211_drv_mutex);
dev = dev_get_by_index(&init_net, ifindex);
if (!dev)
goto out;
if (dev->ieee80211_ptr) {
drv = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
mutex_lock(&drv->mtx);
} else
drv = ERR_PTR(-ENODEV);
dev_put(dev);
out:
mutex_unlock(&cfg80211_drv_mutex);
return drv;
}
void cfg80211_put_dev(struct cfg80211_registered_device *drv)
{
BUG_ON(IS_ERR(drv));
mutex_unlock(&drv->mtx);
}
int cfg80211_dev_rename(struct cfg80211_registered_device *rdev,
char *newname)
{
int idx, taken = -1, result, digits;
/* prohibit calling the thing phy%d when %d is not its number */
sscanf(newname, PHY_NAME "%d%n", &idx, &taken);
if (taken == strlen(newname) && idx != rdev->idx) {
/* count number of places needed to print idx */
digits = 1;
while (idx /= 10)
digits++;
/*
* deny the name if it is phy<idx> where <idx> is printed
* without leading zeroes. taken == strlen(newname) here
*/
if (taken == strlen(PHY_NAME) + digits)
return -EINVAL;
}
/* this will check for collisions */
result = device_rename(&rdev->wiphy.dev, newname);
if (result)
return result;
if (!debugfs_rename(rdev->wiphy.debugfsdir->d_parent,
rdev->wiphy.debugfsdir,
rdev->wiphy.debugfsdir->d_parent,
newname))
printk(KERN_ERR "cfg80211: failed to rename debugfs dir to %s!\n",
newname);
nl80211_notify_dev_rename(rdev);
return 0;
}
/* exported functions */
struct wiphy *wiphy_new(struct cfg80211_ops *ops, int sizeof_priv)
{
struct cfg80211_registered_device *drv;
int alloc_size;
WARN_ON(!ops->add_key && ops->del_key);
WARN_ON(ops->add_key && !ops->del_key);
alloc_size = sizeof(*drv) + sizeof_priv;
drv = kzalloc(alloc_size, GFP_KERNEL);
if (!drv)
return NULL;
drv->ops = ops;
mutex_lock(&cfg80211_drv_mutex);
drv->idx = wiphy_counter;
/* now increase counter for the next device unless
* it has wrapped previously */
if (wiphy_counter >= 0)
wiphy_counter++;
mutex_unlock(&cfg80211_drv_mutex);
if (unlikely(drv->idx < 0)) {
/* ugh, wrapped! */
kfree(drv);
return NULL;
}
/* give it a proper name */
snprintf(drv->wiphy.dev.bus_id, BUS_ID_SIZE,
PHY_NAME "%d", drv->idx);
mutex_init(&drv->mtx);
mutex_init(&drv->devlist_mtx);
INIT_LIST_HEAD(&drv->netdev_list);
device_initialize(&drv->wiphy.dev);
drv->wiphy.dev.class = &ieee80211_class;
drv->wiphy.dev.platform_data = drv;
return &drv->wiphy;
}
EXPORT_SYMBOL(wiphy_new);
int wiphy_register(struct wiphy *wiphy)
{
struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
int res;
mutex_lock(&cfg80211_drv_mutex);
res = device_add(&drv->wiphy.dev);
if (res)
goto out_unlock;
list_add(&drv->list, &cfg80211_drv_list);
/* add to debugfs */
drv->wiphy.debugfsdir =
debugfs_create_dir(wiphy_name(&drv->wiphy),
ieee80211_debugfs_dir);
res = 0;
out_unlock:
mutex_unlock(&cfg80211_drv_mutex);
return res;
}
EXPORT_SYMBOL(wiphy_register);
void wiphy_unregister(struct wiphy *wiphy)
{
struct cfg80211_registered_device *drv = wiphy_to_dev(wiphy);
/* protect the device list */
mutex_lock(&cfg80211_drv_mutex);
BUG_ON(!list_empty(&drv->netdev_list));
/*
* Try to grab drv->mtx. If a command is still in progress,
* hopefully the driver will refuse it since it's tearing
* down the device already. We wait for this command to complete
* before unlinking the item from the list.
* Note: as codified by the BUG_ON above we cannot get here if
* a virtual interface is still associated. Hence, we can only
* get to lock contention here if userspace issues a command
* that identified the hardware by wiphy index.
*/
mutex_lock(&drv->mtx);
/* unlock again before freeing */
mutex_unlock(&drv->mtx);
list_del(&drv->list);
device_del(&drv->wiphy.dev);
debugfs_remove(drv->wiphy.debugfsdir);
mutex_unlock(&cfg80211_drv_mutex);
}
EXPORT_SYMBOL(wiphy_unregister);
void cfg80211_dev_free(struct cfg80211_registered_device *drv)
{
mutex_destroy(&drv->mtx);
mutex_destroy(&drv->devlist_mtx);
kfree(drv);
}
void wiphy_free(struct wiphy *wiphy)
{
put_device(&wiphy->dev);
}
EXPORT_SYMBOL(wiphy_free);
static int cfg80211_netdev_notifier_call(struct notifier_block * nb,
unsigned long state,
void *ndev)
{
struct net_device *dev = ndev;
struct cfg80211_registered_device *rdev;
if (!dev->ieee80211_ptr)
return 0;
rdev = wiphy_to_dev(dev->ieee80211_ptr->wiphy);
switch (state) {
case NETDEV_REGISTER:
mutex_lock(&rdev->devlist_mtx);
list_add(&dev->ieee80211_ptr->list, &rdev->netdev_list);
if (sysfs_create_link(&dev->dev.kobj, &rdev->wiphy.dev.kobj,
"phy80211")) {
printk(KERN_ERR "wireless: failed to add phy80211 "
"symlink to netdev!\n");
}
dev->ieee80211_ptr->netdev = dev;
mutex_unlock(&rdev->devlist_mtx);
break;
case NETDEV_UNREGISTER:
mutex_lock(&rdev->devlist_mtx);
if (!list_empty(&dev->ieee80211_ptr->list)) {
sysfs_remove_link(&dev->dev.kobj, "phy80211");
list_del_init(&dev->ieee80211_ptr->list);
}
mutex_unlock(&rdev->devlist_mtx);
break;
}
return 0;
}
static struct notifier_block cfg80211_netdev_notifier = {
.notifier_call = cfg80211_netdev_notifier_call,
};
static int cfg80211_init(void)
{
int err = wiphy_sysfs_init();
if (err)
goto out_fail_sysfs;
err = register_netdevice_notifier(&cfg80211_netdev_notifier);
if (err)
goto out_fail_notifier;
err = nl80211_init();
if (err)
goto out_fail_nl80211;
ieee80211_debugfs_dir = debugfs_create_dir("ieee80211", NULL);
return 0;
out_fail_nl80211:
unregister_netdevice_notifier(&cfg80211_netdev_notifier);
out_fail_notifier:
wiphy_sysfs_exit();
out_fail_sysfs:
return err;
}
subsys_initcall(cfg80211_init);
static void cfg80211_exit(void)
{
debugfs_remove(ieee80211_debugfs_dir);
nl80211_exit();
unregister_netdevice_notifier(&cfg80211_netdev_notifier);
wiphy_sysfs_exit();
}
module_exit(cfg80211_exit);
