/*
* Scanning routines.
*
* These are not exported because they're assigned to the function pointers.
*
* Copyright (c) 2005, 2006 Johannes Berg <johannes@sipsolutions.net>
* Joseph Jezak <josejx@gentoo.org>
* Larry Finger <Larry.Finger@lwfinger.net>
* Danny van Dyk <kugelfang@gentoo.org>
* Michael Buesch <mbuesch@freenet.de>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
* The full GNU General Public License is included in this distribution in the
* file called COPYING.
*/
#include <linux/completion.h>
#include "ieee80211softmac_priv.h"
/* internal, use to trigger scanning if needed.
* Returns -EBUSY if already scanning,
* result of start_scan otherwise */
int
ieee80211softmac_start_scan(struct ieee80211softmac_device *sm)
{
unsigned long flags;
int ret;
spin_lock_irqsave(&sm->lock, flags);
if (sm->scanning)
{
spin_unlock_irqrestore(&sm->lock, flags);
return -EINPROGRESS;
}
sm->scanning = 1;
spin_unlock_irqrestore(&sm->lock, flags);
ret = sm->start_scan(sm->dev);
if (ret) {
spin_lock_irqsave(&sm->lock, flags);
sm->scanning = 0;
spin_unlock_irqrestore(&sm->lock, flags);
}
return ret;
}
void
ieee80211softmac_stop_scan(struct ieee80211softmac_device *sm)
{
unsigned long flags;
spin_lock_irqsave(&sm->lock, flags);
if (!sm->scanning) {
spin_unlock_irqrestore(&sm->lock, flags);
return;
}
spin_unlock_irqrestore(&sm->lock, flags);
sm->stop_scan(sm->dev);
}
void
ieee80211softmac_wait_for_scan(struct ieee80211softmac_device *sm)
{
unsigned long flags;
spin_lock_irqsave(&sm->lock, flags);
if (!sm->scanning) {
spin_unlock_irqrestore(&sm->lock, flags);
return;
}
spin_unlock_irqrestore(&sm->lock, flags);
sm->wait_for_scan(sm->dev);
}
/* internal scanning implementation follows */
void ieee80211softmac_scan(void *d)
{
int invalid_channel;
u8 current_channel_idx;
struct ieee80211softmac_device *sm = (struct ieee80211softmac_device *)d;
struct ieee80211softmac_scaninfo *si = sm->scaninfo;
unsigned long flags;
while (!(si->stop) && (si->current_channel_idx < si->number_channels)) {
current_channel_idx = si->current_channel_idx;
si->current_channel_idx++; /* go to the next channel */
invalid_channel = (si->skip_flags & si->channels[current_channel_idx].flags);
if (!invalid_channel) {
sm->set_channel(sm->dev, si->channels[current_channel_idx].channel);
// FIXME make this user configurable (active/passive)
if(ieee80211softmac_send_mgt_frame(sm, NULL, IEEE80211_STYPE_PROBE_REQ, 0))
printkl(KERN_DEBUG PFX "Sending Probe Request Failed\n");
/* also send directed management frame for the network we're looking for */
// TODO: is this if correct, or should we do this only if scanning from assoc request?
if (sm->associnfo.req_essid.len)
ieee80211softmac_send_mgt_frame(sm, &sm->associnfo.req_essid, IEEE80211_STYPE_PROBE_REQ, 0);
spin_lock_irqsave(&sm->lock, flags);
if (unlikely(!sm->running)) {
/* Prevent reschedule on workqueue flush */
spin_unlock_irqrestore(&sm->lock, flags);
break;
}
schedule_delayed_work(&si->softmac_scan, IEEE80211SOFTMAC_PROBE_DELAY);
spin_unlock_irqrestore(&sm->lock, flags);
return;
} else {
dprintk(PFX "Not probing Channel %d (not allowed here)\n", si->channels[current_channel_idx].channel);
}
}
spin_lock_irqsave(&sm->lock, flags);
cancel_delayed_work(&si->softmac_scan);
si->started = 0;
spin_unlock_irqrestore(&sm->lock, flags);
dprintk(PFX "Scanning finished\n");
ieee80211softmac_scan_finished(sm);
complete_all(&sm->scaninfo->finished);
}
static inline struct ieee80211softmac_scaninfo *allocate_scaninfo(struct ieee80211softmac_device *mac)
{
/* ugh. can we call this without having the spinlock held? */
struct ieee80211softmac_scaninfo *info = kmalloc(sizeof(struct ieee80211softmac_scaninfo), GFP_ATOMIC);
if (unlikely(!info))
return NULL;
INIT_WORK(&info->softmac_scan, ieee80211softmac_scan, mac);
init_completion(&info->finished);
return info;
}
int ieee80211softmac_start_scan_implementation(struct net_device *dev)
{
struct ieee80211softmac_device *sm = ieee80211_priv(dev);
unsigned long flags;
if (!(dev->flags & IFF_UP))
return -ENODEV;
assert(ieee80211softmac_scan_handlers_check_self(sm));
if (!ieee80211softmac_scan_handlers_check_self(sm))
return -EINVAL;
spin_lock_irqsave(&sm->lock, flags);
/* it looks like we need to hold the lock here
* to make sure we don't allocate two of these... */
if (unlikely(!sm->scaninfo))
sm->scaninfo = allocate_scaninfo(sm);
if (unlikely(!sm->scaninfo)) {
spin_unlock_irqrestore(&sm->lock, flags);
return -ENOMEM;
}
sm->scaninfo->skip_flags = IEEE80211_CH_INVALID;
if (0 /* not scanning in IEEE802.11b */)//TODO
sm->scaninfo->skip_flags |= IEEE80211_CH_B_ONLY;
if (0 /* IEEE802.11a */) {//TODO
sm->scaninfo->channels = sm->ieee->geo.a;
sm->scaninfo->number_channels = sm->ieee->geo.a_channels;
} else {
sm->scaninfo->channels = sm->ieee->geo.bg;
sm->scaninfo->number_channels = sm->ieee->geo.bg_channels;
}
dprintk(PFX "Start scanning with channel: %d\n", sm->scaninfo->channels[0].channel);
dprintk(PFX "Scanning %d channels\n", sm->scaninfo->number_channels);
sm->scaninfo->current_channel_idx = 0;
sm->scaninfo->started = 1;
sm->scaninfo->stop = 0;
INIT_COMPLETION(sm->scaninfo->finished);
schedule_work(&sm->scaninfo->softmac_scan);
spin_unlock_irqrestore(&sm->lock, flags);
return 0;
}
void ieee80211softmac_stop_scan_implementation(struct net_device *dev)
{
struct ieee80211softmac_device *sm = ieee80211_priv(dev);
unsigned long flags;
assert(ieee80211softmac_scan_handlers_check_self(sm));
if (!ieee80211softmac_scan_handlers_check_self(sm))
return;
spin_lock_irqsave(&sm->lock, flags);
assert(sm->scaninfo != NULL);
if (sm->scaninfo) {
if (sm->scaninfo->started)
sm->scaninfo->stop = 1;
else
complete_all(&sm->scaninfo->finished);
}
spin_unlock_irqrestore(&sm->lock, flags);
}
void ieee80211softmac_wait_for_scan_implementation(struct net_device *dev)
{
struct ieee80211softmac_device *sm = ieee80211_priv(dev);
unsigned long flags;
assert(ieee80211softmac_scan_handlers_check_self(sm));
if (!ieee80211softmac_scan_handlers_check_self(sm))
return;
spin_lock_irqsave(&sm->lock, flags);
if (!sm->scaninfo->started) {
spin_unlock_irqrestore(&sm->lock, flags);
return;
}
spin_unlock_irqrestore(&sm->lock, flags);
wait_for_completion(&sm->scaninfo->finished);
}
/* this is what drivers (that do scanning) call when they're done */
void ieee80211softmac_scan_finished(struct ieee80211softmac_device *sm)
{
unsigned long flags;
spin_lock_irqsave(&sm->lock, flags);
sm->scanning = 0;
spin_unlock_irqrestore(&sm->lock, flags);
if (sm->associnfo.bssvalid) {
struct ieee80211softmac_network *net;
net = ieee80211softmac_get_network_by_bssid(sm, sm->associnfo.bssid);
if (net)
sm->set_channel(sm->dev, net->channel);
}
ieee80211softmac_call_events(sm, IEEE80211SOFTMAC_EVENT_SCAN_FINISHED, NULL);
}
EXPORT_SYMBOL_GPL(ieee80211softmac_scan_finished);
