android_kernel_samsung_msm8976/net/mac80211/ieee80211_iface.c
Michael Wu be8755e180 [MAC80211]: improve locking of sta_info related structures
The sta_info code has some awkward locking which prevents some driver
callbacks from being allowed to sleep. This patch makes the locking more
focused so code that calls driver callbacks are allowed to sleep. It also
converts sta_lock to a rwlock.

Signed-off-by: Michael Wu <flamingice@sourmilk.net>
Signed-off-by: Jiri Benc <jbenc@suse.cz>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2007-10-10 16:47:37 -07:00

355 lines
9.3 KiB
C

/*
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2005-2006, Devicescape Software, Inc.
* Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/if_arp.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "sta_info.h"
#include "debugfs_netdev.h"
void ieee80211_if_sdata_init(struct ieee80211_sub_if_data *sdata)
{
int i;
/* Default values for sub-interface parameters */
sdata->drop_unencrypted = 0;
sdata->eapol = 1;
for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
skb_queue_head_init(&sdata->fragments[i].skb_list);
}
static void ieee80211_if_sdata_deinit(struct ieee80211_sub_if_data *sdata)
{
int i;
for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++) {
__skb_queue_purge(&sdata->fragments[i].skb_list);
}
}
/* Must be called with rtnl lock held. */
int ieee80211_if_add(struct net_device *dev, const char *name,
struct net_device **new_dev, int type)
{
struct net_device *ndev;
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
struct ieee80211_sub_if_data *sdata = NULL;
int ret;
ASSERT_RTNL();
ndev = alloc_netdev(sizeof(struct ieee80211_sub_if_data),
name, ieee80211_if_setup);
if (!ndev)
return -ENOMEM;
ret = dev_alloc_name(ndev, ndev->name);
if (ret < 0)
goto fail;
memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
ndev->base_addr = dev->base_addr;
ndev->irq = dev->irq;
ndev->mem_start = dev->mem_start;
ndev->mem_end = dev->mem_end;
SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
sdata = IEEE80211_DEV_TO_SUB_IF(ndev);
ndev->ieee80211_ptr = &sdata->wdev;
sdata->wdev.wiphy = local->hw.wiphy;
sdata->type = IEEE80211_IF_TYPE_AP;
sdata->dev = ndev;
sdata->local = local;
ieee80211_if_sdata_init(sdata);
ret = register_netdevice(ndev);
if (ret)
goto fail;
ieee80211_debugfs_add_netdev(sdata);
ieee80211_if_set_type(ndev, type);
write_lock_bh(&local->sub_if_lock);
if (unlikely(local->reg_state == IEEE80211_DEV_UNREGISTERED)) {
write_unlock_bh(&local->sub_if_lock);
__ieee80211_if_del(local, sdata);
return -ENODEV;
}
list_add(&sdata->list, &local->sub_if_list);
if (new_dev)
*new_dev = ndev;
write_unlock_bh(&local->sub_if_lock);
ieee80211_update_default_wep_only(local);
return 0;
fail:
free_netdev(ndev);
return ret;
}
int ieee80211_if_add_mgmt(struct ieee80211_local *local)
{
struct net_device *ndev;
struct ieee80211_sub_if_data *nsdata;
int ret;
ASSERT_RTNL();
ndev = alloc_netdev(sizeof(struct ieee80211_sub_if_data), "wmgmt%d",
ieee80211_if_mgmt_setup);
if (!ndev)
return -ENOMEM;
ret = dev_alloc_name(ndev, ndev->name);
if (ret < 0)
goto fail;
memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);
SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));
nsdata = IEEE80211_DEV_TO_SUB_IF(ndev);
ndev->ieee80211_ptr = &nsdata->wdev;
nsdata->wdev.wiphy = local->hw.wiphy;
nsdata->type = IEEE80211_IF_TYPE_MGMT;
nsdata->dev = ndev;
nsdata->local = local;
ieee80211_if_sdata_init(nsdata);
ret = register_netdevice(ndev);
if (ret)
goto fail;
ieee80211_debugfs_add_netdev(nsdata);
if (local->open_count > 0)
dev_open(ndev);
local->apdev = ndev;
return 0;
fail:
free_netdev(ndev);
return ret;
}
void ieee80211_if_del_mgmt(struct ieee80211_local *local)
{
struct net_device *apdev;
ASSERT_RTNL();
apdev = local->apdev;
ieee80211_debugfs_remove_netdev(IEEE80211_DEV_TO_SUB_IF(apdev));
local->apdev = NULL;
unregister_netdevice(apdev);
}
void ieee80211_if_set_type(struct net_device *dev, int type)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
int oldtype = sdata->type;
dev->hard_start_xmit = ieee80211_subif_start_xmit;
sdata->type = type;
switch (type) {
case IEEE80211_IF_TYPE_WDS:
sdata->bss = NULL;
break;
case IEEE80211_IF_TYPE_VLAN:
break;
case IEEE80211_IF_TYPE_AP:
sdata->u.ap.dtim_period = 2;
sdata->u.ap.force_unicast_rateidx = -1;
sdata->u.ap.max_ratectrl_rateidx = -1;
skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
sdata->bss = &sdata->u.ap;
break;
case IEEE80211_IF_TYPE_STA:
case IEEE80211_IF_TYPE_IBSS: {
struct ieee80211_sub_if_data *msdata;
struct ieee80211_if_sta *ifsta;
ifsta = &sdata->u.sta;
INIT_WORK(&ifsta->work, ieee80211_sta_work);
setup_timer(&ifsta->timer, ieee80211_sta_timer,
(unsigned long) sdata);
skb_queue_head_init(&ifsta->skb_queue);
ifsta->capab = WLAN_CAPABILITY_ESS;
ifsta->auth_algs = IEEE80211_AUTH_ALG_OPEN |
IEEE80211_AUTH_ALG_SHARED_KEY;
ifsta->create_ibss = 1;
ifsta->wmm_enabled = 1;
ifsta->auto_channel_sel = 1;
ifsta->auto_bssid_sel = 1;
msdata = IEEE80211_DEV_TO_SUB_IF(sdata->local->mdev);
sdata->bss = &msdata->u.ap;
break;
}
case IEEE80211_IF_TYPE_MNTR:
dev->type = ARPHRD_IEEE80211_RADIOTAP;
dev->hard_start_xmit = ieee80211_monitor_start_xmit;
break;
default:
printk(KERN_WARNING "%s: %s: Unknown interface type 0x%x",
dev->name, __FUNCTION__, type);
}
ieee80211_debugfs_change_if_type(sdata, oldtype);
ieee80211_update_default_wep_only(local);
}
/* Must be called with rtnl lock held. */
void ieee80211_if_reinit(struct net_device *dev)
{
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
struct sta_info *sta;
int i;
ASSERT_RTNL();
ieee80211_if_sdata_deinit(sdata);
for (i = 0; i < NUM_DEFAULT_KEYS; i++) {
if (!sdata->keys[i])
continue;
#if 0
/* The interface is down at the moment, so there is not
* really much point in disabling the keys at this point. */
memset(addr, 0xff, ETH_ALEN);
if (local->ops->set_key)
local->ops->set_key(local_to_hw(local), DISABLE_KEY, addr,
local->keys[i], 0);
#endif
ieee80211_key_free(sdata->keys[i]);
sdata->keys[i] = NULL;
}
switch (sdata->type) {
case IEEE80211_IF_TYPE_AP: {
/* Remove all virtual interfaces that use this BSS
* as their sdata->bss */
struct ieee80211_sub_if_data *tsdata, *n;
LIST_HEAD(tmp_list);
write_lock_bh(&local->sub_if_lock);
list_for_each_entry_safe(tsdata, n, &local->sub_if_list, list) {
if (tsdata != sdata && tsdata->bss == &sdata->u.ap) {
printk(KERN_DEBUG "%s: removing virtual "
"interface %s because its BSS interface"
" is being removed\n",
sdata->dev->name, tsdata->dev->name);
list_move_tail(&tsdata->list, &tmp_list);
}
}
write_unlock_bh(&local->sub_if_lock);
list_for_each_entry_safe(tsdata, n, &tmp_list, list)
__ieee80211_if_del(local, tsdata);
kfree(sdata->u.ap.beacon_head);
kfree(sdata->u.ap.beacon_tail);
kfree(sdata->u.ap.generic_elem);
if (dev != local->mdev) {
struct sk_buff *skb;
while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
local->total_ps_buffered--;
dev_kfree_skb(skb);
}
}
break;
}
case IEEE80211_IF_TYPE_WDS:
sta = sta_info_get(local, sdata->u.wds.remote_addr);
if (sta) {
sta_info_free(sta);
sta_info_put(sta);
} else {
#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
printk(KERN_DEBUG "%s: Someone had deleted my STA "
"entry for the WDS link\n", dev->name);
#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
}
break;
case IEEE80211_IF_TYPE_STA:
case IEEE80211_IF_TYPE_IBSS:
kfree(sdata->u.sta.extra_ie);
sdata->u.sta.extra_ie = NULL;
kfree(sdata->u.sta.assocreq_ies);
sdata->u.sta.assocreq_ies = NULL;
kfree(sdata->u.sta.assocresp_ies);
sdata->u.sta.assocresp_ies = NULL;
if (sdata->u.sta.probe_resp) {
dev_kfree_skb(sdata->u.sta.probe_resp);
sdata->u.sta.probe_resp = NULL;
}
break;
case IEEE80211_IF_TYPE_MNTR:
dev->type = ARPHRD_ETHER;
break;
}
/* remove all STAs that are bound to this virtual interface */
sta_info_flush(local, dev);
memset(&sdata->u, 0, sizeof(sdata->u));
ieee80211_if_sdata_init(sdata);
}
/* Must be called with rtnl lock held. */
void __ieee80211_if_del(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata)
{
struct net_device *dev = sdata->dev;
ieee80211_debugfs_remove_netdev(sdata);
unregister_netdevice(dev);
/* Except master interface, the net_device will be freed by
* net_device->destructor (i. e. ieee80211_if_free). */
}
/* Must be called with rtnl lock held. */
int ieee80211_if_remove(struct net_device *dev, const char *name, int id)
{
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
struct ieee80211_sub_if_data *sdata, *n;
ASSERT_RTNL();
write_lock_bh(&local->sub_if_lock);
list_for_each_entry_safe(sdata, n, &local->sub_if_list, list) {
if ((sdata->type == id || id == -1) &&
strcmp(name, sdata->dev->name) == 0 &&
sdata->dev != local->mdev) {
list_del(&sdata->list);
write_unlock_bh(&local->sub_if_lock);
__ieee80211_if_del(local, sdata);
ieee80211_update_default_wep_only(local);
return 0;
}
}
write_unlock_bh(&local->sub_if_lock);
return -ENODEV;
}
void ieee80211_if_free(struct net_device *dev)
{
struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
/* local->apdev must be NULL when freeing management interface */
BUG_ON(dev == local->apdev);
ieee80211_if_sdata_deinit(sdata);
free_netdev(dev);
}