path: root/net/mac80211/rate.c

/*
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
 * Copyright 2017	Intel Deutschland GmbH
 *
 * 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/rtnetlink.h>
#include <linux/module.h>
#include <linux/slab.h>
#include "rate.h"
#include "ieee80211_i.h"
#include "debugfs.h"

struct rate_control_alg {
	struct list_head list;
	const struct rate_control_ops *ops;
};

static LIST_HEAD(rate_ctrl_algs);
static DEFINE_MUTEX(rate_ctrl_mutex);

static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
module_param(ieee80211_default_rc_algo, charp, 0644);
MODULE_PARM_DESC(ieee80211_default_rc_algo,
		 "Default rate control algorithm for mac80211 to use");

void rate_control_rate_init(struct sta_info *sta)
{
	struct ieee80211_local *local = sta->sdata->local;
	struct rate_control_ref *ref = sta->rate_ctrl;
	struct ieee80211_sta *ista = &sta->sta;
	void *priv_sta = sta->rate_ctrl_priv;
	struct ieee80211_supported_band *sband;
	struct ieee80211_chanctx_conf *chanctx_conf;

	ieee80211_sta_set_rx_nss(sta);

	if (!ref)
		return;

	rcu_read_lock();

	chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf);
	if (WARN_ON(!chanctx_conf)) {
		rcu_read_unlock();
		return;
	}

	sband = local->hw.wiphy->bands[chanctx_conf->def.chan->band];

	spin_lock_bh(&sta->rate_ctrl_lock);
	ref->ops->rate_init(ref->priv, sband, &chanctx_conf->def, ista,
			    priv_sta);
	spin_unlock_bh(&sta->rate_ctrl_lock);
	rcu_read_unlock();
	set_sta_flag(sta, WLAN_STA_RATE_CONTROL);
}

void rate_control_tx_status(struct ieee80211_local *local,
			    struct ieee80211_supported_band *sband,
			    struct ieee80211_tx_status *st)
{
	struct rate_control_ref *ref = local->rate_ctrl;
	struct sta_info *sta = container_of(st->sta, struct sta_info, sta);
	void *priv_sta = sta->rate_ctrl_priv;

	if (!ref || !test_sta_flag(sta, WLAN_STA_RATE_CONTROL))
		return;

	spin_lock_bh(&sta->rate_ctrl_lock);
	if (ref->ops->tx_status_ext)
		ref->ops->tx_status_ext(ref->priv, sband, priv_sta, st);
	else if (st->skb)
		ref->ops->tx_status(ref->priv, sband, st->sta, priv_sta, st->skb);
	else
		WARN_ON_ONCE(1);

	spin_unlock_bh(&sta->rate_ctrl_lock);
}

void rate_control_rate_update(struct ieee80211_local *local,
				    struct ieee80211_supported_band *sband,
				    struct sta_info *sta, u32 changed)
{
	struct rate_control_ref *ref = local->rate_ctrl;
	struct ieee80211_sta *ista = &sta->sta;
	void *priv_sta = sta->rate_ctrl_priv;
	struct ieee80211_chanctx_conf *chanctx_conf;

	if (ref && ref->ops->rate_update) {
		rcu_read_lock();

		chanctx_conf = rcu_dereference(sta->sdata->vif.chanctx_conf);
		if (WARN_ON(!chanctx_conf)) {
			rcu_read_unlock();
			return;
		}

		spin_lock_bh(&sta->rate_ctrl_lock);
		ref->ops->rate_update(ref->priv, sband, &chanctx_conf->def,
				      ista, priv_sta, changed);
		spin_unlock_bh(&sta->rate_ctrl_lock);
		rcu_read_unlock();
	}
	drv_sta_rc_update(local, sta->sdata, &sta->sta, changed);
}

int ieee80211_rate_control_register(const struct rate_control_ops *ops)
{
	struct rate_control_alg *alg;

	if (!ops->name)
		return -EINVAL;

	mutex_lock(&rate_ctrl_mutex);
	list_for_each_entry(alg, &rate_ctrl_algs, list) {
		if (!strcmp(alg->ops->name, ops->name)) {
			/* don't register an algorithm twice */
			WARN_ON(1);
			mutex_unlock(&rate_ctrl_mutex);
			return -EALREADY;
		}
	}

	alg = kzalloc(sizeof(*alg), GFP_KERNEL);
	if (alg == NULL) {
		mutex_unlock(&rate_ctrl_mutex);
		return -ENOMEM;
	}
	alg->ops = ops;

	list_add_tail(&alg->list, &rate_ctrl_algs);
	mutex_unlock(&rate_ctrl_mutex);

	return 0;
}
EXPORT_SYMBOL(ieee80211_rate_control_register);

void ieee80211_rate_control_unregister(const struct rate_control_ops *ops)
{
	struct rate_control_alg *alg;

	mutex_lock(&rate_ctrl_mutex);
	list_for_each_entry(alg, &rate_ctrl_algs, list) {
		if (alg->ops == ops) {
			list_del(&alg->list);
			kfree(alg);
			break;
		}
	}
	mutex_unlock(&rate_ctrl_mutex);
}
EXPORT_SYMBOL(ieee80211_rate_control_unregister);

static const struct rate_control_ops *
ieee80211_try_rate_control_ops_get(const char *name)
{
	struct rate_control_alg *alg;
	const struct rate_control_ops *ops = NULL;

	if (!name)
		return NULL;

	mutex_lock(&rate_ctrl_mutex);
	list_for_each_entry(alg, &rate_ctrl_algs, list) {
		if (!strcmp(alg->ops->name, name)) {
			ops = alg->ops;
			break;
		}
	}
	mutex_unlock(&rate_ctrl_mutex);
	return ops;
}

/* Get the rate control algorithm. */
static const