ieee80211softmac_module.c

LINUX 2.6.17.4的源码

	int i;
	struct ieee80211softmac_ratesinfo *ri = &mac->ratesinfo;
	
	for (i=0; i<ri->count-1; i++) {
		if (ri->rates[i] == rate)
			return ri->rates[i+1];
	}
	/* I guess we can't go any higher... */
	return ri->rates[ri->count];
}

u8 ieee80211softmac_lower_rate_delta(struct ieee80211softmac_device *mac, u8 rate, int delta)
{
	int i;
	struct ieee80211softmac_ratesinfo *ri = &mac->ratesinfo;
	
	for (i=delta; i<ri->count; i++) {
		if (ri->rates[i] == rate)
			return ri->rates[i-delta];
	}
	/* I guess we can't go any lower... */
	return ri->rates[0];
}

static void ieee80211softmac_add_txrates_badness(struct ieee80211softmac_device *mac,
						 int amount)
{
	struct ieee80211softmac_txrates oldrates;
	u8 default_rate = mac->txrates.default_rate;
	u8 default_fallback = mac->txrates.default_fallback;
	u32 changes = 0;

	//TODO: This is highly experimental code.
	//      Maybe the dynamic rate selection does not work
	//      and it has to be removed again.

printk("badness %d\n", mac->txrate_badness);
	mac->txrate_badness += amount;
	if (mac->txrate_badness <= -1000) {
		/* Very small badness. Try a faster bitrate. */
		if (mac->txrates_change)
			memcpy(&oldrates, &mac->txrates, sizeof(oldrates));
		default_rate = raise_rate(mac, default_rate);
		changes |= IEEE80211SOFTMAC_TXRATECHG_DEFAULT;
		default_fallback = get_fallback_rate(mac, default_rate);
		changes |= IEEE80211SOFTMAC_TXRATECHG_DEFAULT_FBACK;
		mac->txrate_badness = 0;
printk("Bitrate raised to %u\n", default_rate);
	} else if (mac->txrate_badness >= 10000) {
		/* Very high badness. Try a slower bitrate. */
		if (mac->txrates_change)
			memcpy(&oldrates, &mac->txrates, sizeof(oldrates));
		default_rate = lower_rate(mac, default_rate);
		changes |= IEEE80211SOFTMAC_TXRATECHG_DEFAULT;
		default_fallback = get_fallback_rate(mac, default_rate);
		changes |= IEEE80211SOFTMAC_TXRATECHG_DEFAULT_FBACK;
		mac->txrate_badness = 0;
printk("Bitrate lowered to %u\n", default_rate);
	}

	mac->txrates.default_rate = default_rate;
	mac->txrates.default_fallback = default_fallback;

	if (changes && mac->txrates_change)
		mac->txrates_change(mac->dev, changes, &oldrates);
}

void ieee80211softmac_fragment_lost(struct net_device *dev,
				    u16 wl_seq)
{
	struct ieee80211softmac_device *mac = ieee80211_priv(dev);
	unsigned long flags;

	spin_lock_irqsave(&mac->lock, flags);
	ieee80211softmac_add_txrates_badness(mac, 1000);
	//TODO

	spin_unlock_irqrestore(&mac->lock, flags);
}
EXPORT_SYMBOL_GPL(ieee80211softmac_fragment_lost);

static int rate_cmp(const void *a_, const void *b_) {
	u8 *a, *b;
	a = (u8*)a_;
	b = (u8*)b_;
	return ((*a & ~IEEE80211_BASIC_RATE_MASK) - (*b & ~IEEE80211_BASIC_RATE_MASK));
}

/* Allocate a softmac network struct and fill it from a network */
struct ieee80211softmac_network *
ieee80211softmac_create_network(struct ieee80211softmac_device *mac,
	struct ieee80211_network *net)
{
	struct ieee80211softmac_network *softnet;
	softnet = kzalloc(sizeof(struct ieee80211softmac_network), GFP_ATOMIC);
	if(softnet == NULL)
		return NULL;
	memcpy(softnet->bssid, net->bssid, ETH_ALEN);
	softnet->channel = net->channel;
	softnet->essid.len = net->ssid_len;
	memcpy(softnet->essid.data, net->ssid, softnet->essid.len);
	
	/* copy rates over */
	softnet->supported_rates.count = net->rates_len;
	memcpy(&softnet->supported_rates.rates[0], net->rates, net->rates_len);
	memcpy(&softnet->supported_rates.rates[softnet->supported_rates.count], net->rates_ex, net->rates_ex_len);
	softnet->supported_rates.count += net->rates_ex_len;
	sort(softnet->supported_rates.rates, softnet->supported_rates.count, sizeof(softnet->supported_rates.rates[0]), rate_cmp, NULL);
	
	softnet->capabilities = net->capability;
	return softnet;
}


/* Add a network to the list, while locked */
void
ieee80211softmac_add_network_locked(struct ieee80211softmac_device *mac,
	struct ieee80211softmac_network *add_net)
{
	struct list_head *list_ptr;
	struct ieee80211softmac_network *softmac_net = NULL;

	list_for_each(list_ptr, &mac->network_list) {
		softmac_net = list_entry(list_ptr, struct ieee80211softmac_network, list);
		if(!memcmp(softmac_net->bssid, add_net->bssid, ETH_ALEN))
			break;
		else
			softmac_net = NULL;
	}
	if(softmac_net == NULL)
		list_add(&(add_net->list), &mac->network_list);
}

/* Add a network to the list, with locking */
void
ieee80211softmac_add_network(struct ieee80211softmac_device *mac,
	struct ieee80211softmac_network *add_net)
{
	unsigned long flags;
	spin_lock_irqsave(&mac->lock, flags);
	ieee80211softmac_add_network_locked(mac, add_net);
	spin_unlock_irqrestore(&mac->lock, flags);
}


/* Delete a network from the list, while locked*/
void
ieee80211softmac_del_network_locked(struct ieee80211softmac_device *mac,
	struct ieee80211softmac_network *del_net)
{
	list_del(&(del_net->list));
}

/* Delete a network from the list with locking */
void
ieee80211softmac_del_network(struct ieee80211softmac_device *mac,
	struct ieee80211softmac_network *del_net)
{
	unsigned long flags;
	spin_lock_irqsave(&mac->lock, flags);
	ieee80211softmac_del_network_locked(mac, del_net);
	spin_unlock_irqrestore(&mac->lock, flags);
}

/* Get a network from the list by MAC while locked */
struct ieee80211softmac_network *
ieee80211softmac_get_network_by_bssid_locked(struct ieee80211softmac_device *mac,
	u8 *bssid)
{
	struct list_head *list_ptr;
	struct ieee80211softmac_network *softmac_net = NULL;
	list_for_each(list_ptr, &mac->network_list) {
		softmac_net = list_entry(list_ptr, struct ieee80211softmac_network, list);
		if(!memcmp(softmac_net->bssid, bssid, ETH_ALEN))
			break;
		else
			softmac_net = NULL;
	}
	return softmac_net;
}

/* Get a network from the list by BSSID with locking */
struct ieee80211softmac_network *
ieee80211softmac_get_network_by_bssid(struct ieee80211softmac_device *mac,
	u8 *bssid)
{
	unsigned long flags;
	struct ieee80211softmac_network *softmac_net;
	
	spin_lock_irqsave(&mac->lock, flags);
	softmac_net = ieee80211softmac_get_network_by_bssid_locked(mac, bssid);
	spin_unlock_irqrestore(&mac->lock, flags);
	return softmac_net;
}

/* Get a network from the list by ESSID while locked */
struct ieee80211softmac_network *
ieee80211softmac_get_network_by_essid_locked(struct ieee80211softmac_device *mac,
	struct ieee80211softmac_essid *essid)
{
	struct list_head *list_ptr;
	struct ieee80211softmac_network *softmac_net = NULL;

	list_for_each(list_ptr, &mac->network_list) {
		softmac_net = list_entry(list_ptr, struct ieee80211softmac_network, list);
		if (softmac_net->essid.len == essid->len &&
			!memcmp(softmac_net->essid.data, essid->data, essid->len))
			return softmac_net;
	}
	return NULL;
}

/* Get a network from the list by ESSID with locking */
struct ieee80211softmac_network *
ieee80211softmac_get_network_by_essid(struct ieee80211softmac_device *mac,
	struct ieee80211softmac_essid *essid)	
{
	unsigned long flags;
	struct ieee80211softmac_network *softmac_net = NULL;

	spin_lock_irqsave(&mac->lock, flags);
	softmac_net = ieee80211softmac_get_network_by_essid_locked(mac, essid);	
	spin_unlock_irqrestore(&mac->lock, flags);
	return softmac_net;
}

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Johannes Berg");
MODULE_AUTHOR("Joseph Jezak");
MODULE_AUTHOR("Larry Finger");
MODULE_AUTHOR("Danny van Dyk");
MODULE_AUTHOR("Michael Buesch");
MODULE_DESCRIPTION("802.11 software MAC");