[linux-2.6-block.git] / net / mac80211 / rate.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/rtnetlink.h>
#include "rate.h"
#include "ieee80211_i.h"
#include "debugfs.h"

struct rate_control_alg {
	struct list_head list;
	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");

int ieee80211_rate_control_register(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(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 struct rate_control_ops *
ieee80211_try_rate_control_ops_get(const char *name)
{
	struct rate_control_alg *alg;
	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))
			if (try_module_get(alg->ops->module)) {
				ops = alg->ops;
				break;
			}
	}
	mutex_unlock(&rate_ctrl_mutex);
	return ops;
}

/* Get the rate control algorithm. */
static struct rate_control_ops *
ieee80211_rate_control_ops_get(const char *name)
{
	struct rate_control_ops *ops;
	const char *alg_name;

	if (!name)
		alg_name = ieee80211_default_rc_algo;
	else
		alg_name = name;

	ops = ieee80211_try_rate_control_ops_get(alg_name);
	if (!ops) {
		request_module("rc80211_%s", alg_name);
		ops = ieee80211_try_rate_control_ops_get(alg_name);
	}
	if (!ops && name)
		/* try default if specific alg requested but not found */
		ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);

	/* try built-in one if specific alg requested but not found */
	if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT))
		ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);

	return ops;
}

static void ieee80211_rate_control_ops_put(struct rate_control_ops *ops)
{
	module_put(ops->module);
}

#ifdef CONFIG_MAC80211_DEBUGFS
static ssize_t rcname_read(struct file *file, char __user *userbuf,
			   size_t count, loff_t *ppos)
{
	struct rate_control_ref *ref = file->private_data;
	int len = strlen(ref->ops->name);

	return simple_read_from_buffer(userbuf, count, ppos,
				       ref->ops->name, len);
}

static const struct file_operations rcname_ops = {
	.read = rcname_read,
	.open = mac80211_open_file_generic,
};
#endif

static struct rate_control_ref *rate_control_alloc(const char *name,
					    struct ieee80211_local *local)
{
	struct dentry *debugfsdir = NULL;
	struct rate_control_ref *ref;

	ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
	if (!ref)
		goto fail_ref;
	kref_init(&ref->kref);
	ref->local = local;
	ref->ops = ieee80211_rate_control_ops_get(name);
	if (!ref->ops)
		goto fail_ops;

#ifdef CONFIG_MAC80211_DEBUGFS
	debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir);
	local->debugfs.rcdir = debugfsdir;
	debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops);
#endif

	ref->priv = ref->ops->alloc(&local->hw, debugfsdir);
	if (!ref->priv)
		goto fail_priv;
	return ref;

fail_priv:
	ieee80211_rate_control_ops_put(ref->ops);
fail_ops:
	kfree(ref);
fail_ref:
	return NULL;
}

static void rate_control_release(struct kref *kref)
{
	struct rate_control_ref *ctrl_ref;

	ctrl_ref = container_of(kref, struct rate_control_ref, kref);
	ctrl_ref->ops->free(ctrl_ref->priv);

#ifdef CONFIG_MAC80211_DEBUGFS
	debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir);
	ctrl_ref->local->debugfs.rcdir = NULL;
#endif

	ieee80211_rate_control_ops_put(ctrl_ref->ops);
	kfree(ctrl_ref);
}

static bool rc_no_data_or_no_ack(struct ieee80211_tx_rate_control *txrc)
{
	struct sk_buff *skb = txrc->skb;
	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	__le16 fc;

	fc = hdr->frame_control;

	return ((info->flags & IEEE80211_TX_CTL_NO_ACK) || !ieee80211_is_data(fc));
}

static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, u8 max_rate_idx)
{
	u8 i;

	if (basic_rates == 0)
		return; /* assume basic rates unknown and accept rate */
	if (*idx < 0)
		return;
	if (basic_rates & (1 << *idx))
		return; /* selected rate is a basic rate */

	for (i = *idx + 1; i <= max_rate_idx; i++) {
		if (basic_rates & (1 << i)) {
			*idx = i;
			return;
		}
	}

	/* could not find a basic rate; use original selection */
}

bool rate_control_send_low(struct ieee80211_sta *sta,
			   void *priv_sta,
			   struct ieee80211_tx_rate_control *txrc)
{
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);

	if (!sta || !priv_sta || rc_no_data_or_no_ack(txrc)) {
		info->control.rates[0].idx = rate_lowest_index(txrc->sband, sta);
		info->control.rates[0].count =
			(info->flags & IEEE80211_TX_CTL_NO_ACK) ?
			1 : txrc->hw->max_rate_tries;
		if (!sta && txrc->ap)
			rc_send_low_broadcast(&info->control.rates[0].idx,
					      txrc->bss_conf->basic_rates,
					      txrc->sband->n_bitrates);
		return true;
	}
	return false;
}
EXPORT_SYMBOL(rate_control_send_low);

static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
				int n_bitrates, u32 mask)
{
	int j;

	/* See whether the selected rate or anything below it is allowed. */
	for (j = rate->idx; j >= 0; j--) {
		if (mask & (1 << j)) {
			/* Okay, found a suitable rate. Use it. */
			rate->idx = j;
			return;
		}
	}

	/* Try to find a higher rate that would be allowed */
	for (j = rate->idx + 1; j < n_bitrates; j++) {
		if (mask & (1 << j)) {
			/* Okay, found a suitable rate. Use it. */
			rate->idx = j;
			return;
		}
	}

	/*
	 * Uh.. No suitable rate exists. This should not really happen with
	 * sane TX rate mask configurations. However, should someone manage to
	 * configure supported rates and TX rate mask in incompatible way,
	 * allow the frame to be transmitted with whatever the rate control
	 * selected.
	 */
}

void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
			   struct sta_info *sta,
			   struct ieee80211_tx_rate_control *txrc)
{
	struct rate_control_ref *ref = sdata->local->rate_ctrl;
	void *priv_sta = NULL;
	struct ieee80211_sta *ista = NULL;
	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
	int i;
	u32 mask;

	if (sta) {
		ista = &sta->sta;
		priv_sta = sta->rate_ctrl_priv;
	}

	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
		info->control.rates[i].idx = -1;
		info->control.rates[i].flags = 0;
		info->control.rates[i].count = 1;
	}

	if (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
		return;

	ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);

	/*
	 * Try to enforce the rateidx mask the user wanted. skip this if the
	 * default mask (allow all rates) is used to save some processing for
	 * the common case.
	 */
	mask = sdata->rc_rateidx_mask[info->band];
	if (mask != (1 << txrc->sband->n_bitrates) - 1) {
		if (sta) {
			/* Filter out rates that the STA does not support */
			mask &= sta->sta.supp_rates[info->band];
		}
		/*
		 * Make sure the rate index selected for each TX rate is
		 * included in the configured mask and change the rate indexes
		 * if needed.
		 */
		for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
			/* Rate masking supports only legacy rates for now */
			if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS)
				continue;
			rate_idx_match_mask(&info->control.rates[i],
					    txrc->sband->n_bitrates, mask);
		}
	}

	BUG_ON(info->control.rates[0].idx < 0);
}

struct rate_control_ref *rate_control_get(struct rate_control_ref *ref)
{
	kref_get(&ref->kref);
	return ref;
}

void rate_control_put(struct rate_control_ref *ref)
{
	kref_put(&ref->kref, rate_control_release);
}

int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
				 const char *name)
{
	struct rate_control_ref *ref, *old;

	ASSERT_RTNL();

	if (local->open_count)
		return -EBUSY;

	if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) {
		if (WARN_ON(!local->ops->set_rts_threshold))
			return -EINVAL;
		return 0;
	}

	ref = rate_control_alloc(name, local);
	if (!ref) {
		printk(KERN_WARNING "%s: Failed to select rate control "
		       "algorithm\n", wiphy_name(local->hw.wiphy));
		return -ENOENT;
	}

	old = local->rate_ctrl;
	local->rate_ctrl = ref;
	if (old) {
		rate_control_put(old);
		sta_info_flush(local, NULL);
	}

	printk(KERN_DEBUG "%s: Selected rate control "
	       "algorithm '%s'\n", wiphy_name(local->hw.wiphy),
	       ref->ops->name);

	return 0;
}

void rate_control_deinitialize(struct ieee80211_local *local)
{
	struct rate_control_ref *ref;

	ref = local->rate_ctrl;

	if (!ref)
		return;

	local->rate_ctrl = NULL;
	rate_control_put(ref);
}
Commit	Line	Data
f0706e82 JB	1	/*
	2	* Copyright 2002-2005, Instant802 Networks, Inc.
	3	* Copyright 2005-2006, Devicescape Software, Inc.
	4	* Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 as
	8	* published by the Free Software Foundation.
	9	*/
	10
	11	#include <linux/kernel.h>
ff688089	12	#include <linux/rtnetlink.h>
2c8dccc7	13	#include "rate.h"
f0706e82	14	#include "ieee80211_i.h"
4b7679a5	15	#include "debugfs.h"
f0706e82 JB	16
	17	struct rate_control_alg {
	18	struct list_head list;
	19	struct rate_control_ops *ops;
	20	};
	21
	22	static LIST_HEAD(rate_ctrl_algs);
	23	static DEFINE_MUTEX(rate_ctrl_mutex);
	24
c21b39ac SB	25	static char *ieee80211_default_rc_algo = CONFIG_MAC80211_RC_DEFAULT;
	26	module_param(ieee80211_default_rc_algo, charp, 0644);
	27	MODULE_PARM_DESC(ieee80211_default_rc_algo,
	28	"Default rate control algorithm for mac80211 to use");
	29
f0706e82 JB	30	int ieee80211_rate_control_register(struct rate_control_ops *ops)
	31	{
	32	struct rate_control_alg *alg;
	33
ac71c691 JB	34	if (!ops->name)
	35	return -EINVAL;
	36
999acd9c JB	37	mutex_lock(&rate_ctrl_mutex);
	38	list_for_each_entry(alg, &rate_ctrl_algs, list) {
	39	if (!strcmp(alg->ops->name, ops->name)) {
	40	/* don't register an algorithm twice */
	41	WARN_ON(1);
b808ab16	42	mutex_unlock(&rate_ctrl_mutex);
999acd9c JB	43	return -EALREADY;
	44	}
	45	}
	46
dd00cc48	47	alg = kzalloc(sizeof(*alg), GFP_KERNEL);
f0706e82	48	if (alg == NULL) {
999acd9c	49	mutex_unlock(&rate_ctrl_mutex);
f0706e82 JB	50	return -ENOMEM;
f0706e82 JB	51	}
f0706e82 JB	52	alg->ops = ops;
f0706e82 JB	53
f0706e82 JB	54	list_add_tail(&alg->list, &rate_ctrl_algs);
	55	mutex_unlock(&rate_ctrl_mutex);
	56
	57	return 0;
	58	}
	59	EXPORT_SYMBOL(ieee80211_rate_control_register);
	60
	61	void ieee80211_rate_control_unregister(struct rate_control_ops *ops)
	62	{
	63	struct rate_control_alg *alg;
	64
	65	mutex_lock(&rate_ctrl_mutex);
	66	list_for_each_entry(alg, &rate_ctrl_algs, list) {
	67	if (alg->ops == ops) {
	68	list_del(&alg->list);
20880e89	69	kfree(alg);
f0706e82 JB	70	break;
	71	}
	72	}
	73	mutex_unlock(&rate_ctrl_mutex);
f0706e82 JB	74	}
	75	EXPORT_SYMBOL(ieee80211_rate_control_unregister);
	76
	77	static struct rate_control_ops *
	78	ieee80211_try_rate_control_ops_get(const char *name)
	79	{
	80	struct rate_control_alg *alg;
	81	struct rate_control_ops *ops = NULL;
	82
ac71c691 JB	83	if (!name)
	84	return NULL;
	85
f0706e82 JB	86	mutex_lock(&rate_ctrl_mutex);
f0706e82 JB	87	list_for_each_entry(alg, &rate_ctrl_algs, list) {
ac71c691	88	if (!strcmp(alg->ops->name, name))
f0706e82 JB	89	if (try_module_get(alg->ops->module)) {
	90	ops = alg->ops;
	91	break;
	92	}
	93	}
	94	mutex_unlock(&rate_ctrl_mutex);
	95	return ops;
	96	}
	97
c21b39ac	98	/* Get the rate control algorithm. */
f0706e82 JB	99	static struct rate_control_ops *
	100	ieee80211_rate_control_ops_get(const char *name)
	101	{
	102	struct rate_control_ops *ops;
c21b39ac	103	const char *alg_name;
f0706e82	104
ac71c691	105	if (!name)
c21b39ac SB	106	alg_name = ieee80211_default_rc_algo;
	107	else
	108	alg_name = name;
ac71c691	109
c21b39ac	110	ops = ieee80211_try_rate_control_ops_get(alg_name);
f0706e82	111	if (!ops) {
c21b39ac SB	112	request_module("rc80211_%s", alg_name);
c21b39ac SB	113	ops = ieee80211_try_rate_control_ops_get(alg_name);
f0706e82	114	}
c21b39ac SB	115	if (!ops && name)
	116	/* try default if specific alg requested but not found */
	117	ops = ieee80211_try_rate_control_ops_get(ieee80211_default_rc_algo);
	118
4b475898 JB	119	/* try built-in one if specific alg requested but not found */
	120	if (!ops && strlen(CONFIG_MAC80211_RC_DEFAULT))
	121	ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
	122
f0706e82 JB	123	return ops;
	124	}
	125
	126	static void ieee80211_rate_control_ops_put(struct rate_control_ops *ops)
	127	{
	128	module_put(ops->module);
	129	}
	130
4b7679a5 JB	131	#ifdef CONFIG_MAC80211_DEBUGFS
	132	static ssize_t rcname_read(struct file file, char __user userbuf,
	133	size_t count, loff_t *ppos)
	134	{
	135	struct rate_control_ref *ref = file->private_data;
	136	int len = strlen(ref->ops->name);
	137
	138	return simple_read_from_buffer(userbuf, count, ppos,
	139	ref->ops->name, len);
	140	}
	141
	142	static const struct file_operations rcname_ops = {
	143	.read = rcname_read,
	144	.open = mac80211_open_file_generic,
	145	};
	146	#endif
	147
209c671d	148	static struct rate_control_ref rate_control_alloc(const char name,
f0706e82 JB	149	struct ieee80211_local *local)
f0706e82 JB	150	{
4b7679a5	151	struct dentry *debugfsdir = NULL;
f0706e82 JB	152	struct rate_control_ref *ref;
	153
	154	ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
	155	if (!ref)
	156	goto fail_ref;
	157	kref_init(&ref->kref);
4b7679a5	158	ref->local = local;
f0706e82 JB	159	ref->ops = ieee80211_rate_control_ops_get(name);
	160	if (!ref->ops)
	161	goto fail_ops;
4b7679a5 JB	162
	163	#ifdef CONFIG_MAC80211_DEBUGFS
	164	debugfsdir = debugfs_create_dir("rc", local->hw.wiphy->debugfsdir);
	165	local->debugfs.rcdir = debugfsdir;
7bcfaf2f	166	debugfs_create_file("name", 0400, debugfsdir, ref, &rcname_ops);
4b7679a5 JB	167	#endif
	168
	169	ref->priv = ref->ops->alloc(&local->hw, debugfsdir);
f0706e82 JB	170	if (!ref->priv)
	171	goto fail_priv;
	172	return ref;
	173
	174	fail_priv:
	175	ieee80211_rate_control_ops_put(ref->ops);
	176	fail_ops:
	177	kfree(ref);
	178	fail_ref:
	179	return NULL;
	180	}
	181
	182	static void rate_control_release(struct kref *kref)
	183	{
	184	struct rate_control_ref *ctrl_ref;
	185
	186	ctrl_ref = container_of(kref, struct rate_control_ref, kref);
	187	ctrl_ref->ops->free(ctrl_ref->priv);
4b7679a5 JB	188
4b7679a5 JB	189	#ifdef CONFIG_MAC80211_DEBUGFS
7bcfaf2f	190	debugfs_remove_recursive(ctrl_ref->local->debugfs.rcdir);
4b7679a5 JB	191	ctrl_ref->local->debugfs.rcdir = NULL;
	192	#endif
	193
f0706e82 JB	194	ieee80211_rate_control_ops_put(ctrl_ref->ops);
	195	kfree(ctrl_ref);
	196	}
	197
4c6d4f5c LR	198	static bool rc_no_data_or_no_ack(struct ieee80211_tx_rate_control *txrc)
	199	{
	200	struct sk_buff *skb = txrc->skb;
	201	struct ieee80211_hdr hdr = (struct ieee80211_hdr ) skb->data;
	202	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
	203	__le16 fc;
	204
	205	fc = hdr->frame_control;
	206
	207	return ((info->flags & IEEE80211_TX_CTL_NO_ACK) \|\| !ieee80211_is_data(fc));
	208	}
	209
e00cfce0 JM	210	static void rc_send_low_broadcast(s8 *idx, u32 basic_rates, u8 max_rate_idx)
	211	{
	212	u8 i;
	213
	214	if (basic_rates == 0)
	215	return; /* assume basic rates unknown and accept rate */
	216	if (*idx < 0)
	217	return;
	218	if (basic_rates & (1 << *idx))
	219	return; /* selected rate is a basic rate */
	220
	221	for (i = *idx + 1; i <= max_rate_idx; i++) {
	222	if (basic_rates & (1 << i)) {
	223	*idx = i;
	224	return;
	225	}
	226	}
	227
	228	/* could not find a basic rate; use original selection */
	229	}
	230
4c6d4f5c LR	231	bool rate_control_send_low(struct ieee80211_sta *sta,
	232	void *priv_sta,
	233	struct ieee80211_tx_rate_control *txrc)
	234	{
	235	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
	236
	237	if (!sta \|\| !priv_sta \|\| rc_no_data_or_no_ack(txrc)) {
	238	info->control.rates[0].idx = rate_lowest_index(txrc->sband, sta);
	239	info->control.rates[0].count =
	240	(info->flags & IEEE80211_TX_CTL_NO_ACK) ?
	241	1 : txrc->hw->max_rate_tries;
e00cfce0 JM	242	if (!sta && txrc->ap)
	243	rc_send_low_broadcast(&info->control.rates[0].idx,
	244	txrc->bss_conf->basic_rates,
	245	txrc->sband->n_bitrates);
4c6d4f5c LR	246	return true;
	247	}
	248	return false;
	249	}
	250	EXPORT_SYMBOL(rate_control_send_low);
	251
37eb0b16 JM	252	static void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
	253	int n_bitrates, u32 mask)
	254	{
	255	int j;
	256
	257	/* See whether the selected rate or anything below it is allowed. */
	258	for (j = rate->idx; j >= 0; j--) {
	259	if (mask & (1 << j)) {
	260	/* Okay, found a suitable rate. Use it. */
	261	rate->idx = j;
	262	return;
	263	}
	264	}
	265
	266	/* Try to find a higher rate that would be allowed */
	267	for (j = rate->idx + 1; j < n_bitrates; j++) {
	268	if (mask & (1 << j)) {
	269	/* Okay, found a suitable rate. Use it. */
	270	rate->idx = j;
	271	return;
	272	}
	273	}
	274
	275	/*
	276	* Uh.. No suitable rate exists. This should not really happen with
	277	* sane TX rate mask configurations. However, should someone manage to
	278	* configure supported rates and TX rate mask in incompatible way,
	279	* allow the frame to be transmitted with whatever the rate control
	280	* selected.
	281	*/
	282	}
	283
4b7679a5	284	void rate_control_get_rate(struct ieee80211_sub_if_data *sdata,
e6a9854b JB	285	struct sta_info *sta,
e6a9854b JB	286	struct ieee80211_tx_rate_control *txrc)
1abbe498	287	{
4b7679a5 JB	288	struct rate_control_ref *ref = sdata->local->rate_ctrl;
	289	void *priv_sta = NULL;
	290	struct ieee80211_sta *ista = NULL;
e6a9854b	291	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
1abbe498	292	int i;
37eb0b16	293	u32 mask;
1abbe498	294
4b7679a5 JB	295	if (sta) {
	296	ista = &sta->sta;
	297	priv_sta = sta->rate_ctrl_priv;
	298	}
	299
e6a9854b JB	300	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
	301	info->control.rates[i].idx = -1;
	302	info->control.rates[i].flags = 0;
	303	info->control.rates[i].count = 1;
	304	}
	305
5affcd6b JO	306	if (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
	307	return;
	308
37eb0b16	309	ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
e6a9854b JB	310
e6a9854b JB	311	/*
37eb0b16 JM	312	* Try to enforce the rateidx mask the user wanted. skip this if the
	313	* default mask (allow all rates) is used to save some processing for
	314	* the common case.
e6a9854b	315	*/
37eb0b16 JM	316	mask = sdata->rc_rateidx_mask[info->band];
	317	if (mask != (1 << txrc->sband->n_bitrates) - 1) {
	318	if (sta) {
	319	/* Filter out rates that the STA does not support */
	320	mask &= sta->sta.supp_rates[info->band];
	321	}
	322	/*
	323	* Make sure the rate index selected for each TX rate is
	324	* included in the configured mask and change the rate indexes
	325	* if needed.
	326	*/
e6a9854b	327	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
37eb0b16	328	/* Rate masking supports only legacy rates for now */
e6a9854b JB	329	if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS)
e6a9854b JB	330	continue;
37eb0b16 JM	331	rate_idx_match_mask(&info->control.rates[i],
	332	txrc->sband->n_bitrates, mask);
	333	}
1abbe498	334	}
e6a9854b JB	335
e6a9854b JB	336	BUG_ON(info->control.rates[0].idx < 0);
1abbe498 MN	337	}
1abbe498 MN	338
f0706e82 JB	339	struct rate_control_ref rate_control_get(struct rate_control_ref ref)
	340	{
	341	kref_get(&ref->kref);
	342	return ref;
	343	}
	344
	345	void rate_control_put(struct rate_control_ref *ref)
	346	{
	347	kref_put(&ref->kref, rate_control_release);
	348	}
ff688089 JB	349
	350	int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
	351	const char *name)
	352	{
	353	struct rate_control_ref ref, old;
	354
	355	ASSERT_RTNL();
af65cd96	356
3b8d81e0	357	if (local->open_count)
ff688089 JB	358	return -EBUSY;
ff688089 JB	359
af65cd96 JB	360	if (local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) {
	361	if (WARN_ON(!local->ops->set_rts_threshold))
	362	return -EINVAL;
	363	return 0;
	364	}
	365
ff688089 JB	366	ref = rate_control_alloc(name, local);
	367	if (!ref) {
	368	printk(KERN_WARNING "%s: Failed to select rate control "
dd1cd4c6	369	"algorithm\n", wiphy_name(local->hw.wiphy));
ff688089 JB	370	return -ENOENT;
	371	}
	372
	373	old = local->rate_ctrl;
	374	local->rate_ctrl = ref;
	375	if (old) {
	376	rate_control_put(old);
	377	sta_info_flush(local, NULL);
	378	}
	379
	380	printk(KERN_DEBUG "%s: Selected rate control "
dd1cd4c6	381	"algorithm '%s'\n", wiphy_name(local->hw.wiphy),
ff688089 JB	382	ref->ops->name);
ff688089 JB	383
ff688089 JB	384	return 0;
	385	}
	386
	387	void rate_control_deinitialize(struct ieee80211_local *local)
	388	{
	389	struct rate_control_ref *ref;
	390
	391	ref = local->rate_ctrl;
af65cd96 JB	392
	393	if (!ref)
	394	return;
	395
ff688089 JB	396	local->rate_ctrl = NULL;
	397	rate_control_put(ref);
	398	}
c21b39ac	399