Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 996 insertions, 0 deletions

diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
new file mode 100644
index 000000000..954b932fd
--- /dev/null
+++ b/net/mac80211/rate.c
@@ -0,0 +1,996 @@
+/*
+ * 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 struct rate_control_ops *
+ieee80211_rate_control_ops_get(const char *name)
+{
+	const struct rate_control_ops *ops;
+	const char *alg_name;
+
+	kernel_param_lock(THIS_MODULE);
+	if (!name)
+		alg_name = ieee80211_default_rc_algo;
+	else
+		alg_name = 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);
+
+	/* Note: check for > 0 is intentional to avoid clang warning */
+	if (!ops && (strlen(CONFIG_MAC80211_RC_DEFAULT) > 0))
+		/* try built-in one if specific alg requested but not found */
+		ops = ieee80211_try_rate_control_ops_get(CONFIG_MAC80211_RC_DEFAULT);
+
+	kernel_param_unlock(THIS_MODULE);
+
+	return ops;
+}
+
+#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 = simple_open,
+	.llseek = default_llseek,
+};
+#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)
+		return NULL;
+	ref->ops = ieee80211_rate_control_ops_get(name);
+	if (!ref->ops)
+		goto free;
+
+#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 free;
+	return ref;
+
+free:
+	kfree(ref);
+	return NULL;
+}
+
+static void rate_control_free(struct ieee80211_local *local,
+			      struct rate_control_ref *ctrl_ref)
+{
+	ctrl_ref->ops->free(ctrl_ref->priv);
+
+#ifdef CONFIG_MAC80211_DEBUGFS
+	debugfs_remove_recursive(local->debugfs.rcdir);
+	local->debugfs.rcdir = NULL;
+#endif
+
+	kfree(ctrl_ref);
+}
+
+void ieee80211_check_rate_mask(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_supported_band *sband;
+	u32 user_mask, basic_rates = sdata->vif.bss_conf.basic_rates;
+	enum nl80211_band band;
+
+	if (WARN_ON(!sdata->vif.bss_conf.chandef.chan))
+		return;
+
+	if (WARN_ON_ONCE(!basic_rates))
+		return;
+
+	band = sdata->vif.bss_conf.chandef.chan->band;
+	user_mask = sdata->rc_rateidx_mask[band];
+	sband = local->hw.wiphy->bands[band];
+
+	if (user_mask & basic_rates)
+		return;
+
+	sdata_dbg(sdata,
+		  "no overlap between basic rates (0x%x) and user mask (0x%x on band %d) - clearing the latter",
+		  basic_rates, user_mask, band);
+	sdata->rc_rateidx_mask[band] = (1 << sband->n_bitrates) - 1;
+}
+
+static bool rc_no_data_or_no_ack_use_min(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_TX_CTL_USE_MINRATE)) ||
+		!ieee80211_is_data(fc);
+}
+
+static void rc_send_low_basicrate(s8 *idx, u32 basic_rates,
+				  struct ieee80211_supported_band *sband)
+{
+	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 <= sband->n_bitrates; i++) {
+		if (basic_rates & (1 << i)) {
+			*idx = i;
+			return;
+		}
+	}
+
+	/* could not find a basic rate; use original selection */
+}
+
+static void __rate_control_send_low(struct ieee80211_hw *hw,
+				    struct ieee80211_supported_band *sband,
+				    struct ieee80211_sta *sta,
+				    struct ieee80211_tx_info *info,
+				    u32 rate_mask)
+{
+	int i;
+	u32 rate_flags =
+		ieee80211_chandef_rate_flags(&hw->conf.chandef);
+
+	if ((sband->band == NL80211_BAND_2GHZ) &&
+	    (info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
+		rate_flags |= IEEE80211_RATE_ERP_G;
+
+	info->control.rates[0].idx = 0;
+	for (i = 0; i < sband->n_bitrates; i++) {
+		if (!(rate_mask & BIT(i)))
+			continue;
+
+		if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
+			continue;
+
+		if (!rate_supported(sta, sband->band, i))
+			continue;
+
+		info->control.rates[0].idx = i;
+		break;
+	}
+	WARN_ONCE(i == sband->n_bitrates,
+		  "no supported rates (0x%x) in rate_mask 0x%x with flags 0x%x\n",
+		  sta ? sta->supp_rates[sband->band] : -1,
+		  rate_mask, rate_flags);
+
+	info->control.rates[0].count =
+		(info->flags & IEEE80211_TX_CTL_NO_ACK) ?
+		1 : hw->max_rate_tries;
+
+	info->control.skip_table = 1;
+}
+
+
+bool rate_control_send_low(struct ieee80211_sta *pubsta,
+			   void *priv_sta,
+			   struct ieee80211_tx_rate_control *txrc)
+{
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(txrc->skb);
+	struct ieee80211_supported_band *sband = txrc->sband;
+	struct sta_info *sta;
+	int mcast_rate;
+	bool use_basicrate = false;
+
+	if (!pubsta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) {
+		__rate_control_send_low(txrc->hw, sband, pubsta, info,
+					txrc->rate_idx_mask);
+
+		if (!pubsta && txrc->bss) {
+			mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
+			if (mcast_rate > 0) {
+				info->control.rates[0].idx = mcast_rate - 1;
+				return true;
+			}
+			use_basicrate = true;
+		} else if (pubsta) {
+			sta = container_of(pubsta, struct sta_info, sta);
+			if (ieee80211_vif_is_mesh(&sta->sdata->vif))
+				use_basicrate = true;
+		}
+
+		if (use_basicrate)
+			rc_send_low_basicrate(&info->control.rates[0].idx,
+					      txrc->bss_conf->basic_rates,
+					      sband);
+
+		return true;
+	}
+	return false;
+}
+EXPORT_SYMBOL(rate_control_send_low);
+
+static bool rate_idx_match_legacy_mask(s8 *rate_idx, 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 true;
+		}
+	}
+
+	/* 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 true;
+		}
+	}
+	return false;
+}
+
+static bool rate_idx_match_mcs_mask(s8 *rate_idx, u8 *mcs_mask)
+{
+	int i, j;
+	int ridx, rbit;
+
+	ridx = *rate_idx / 8;
+	rbit = *rate_idx % 8;
+
+	/* sanity check */
+	if (ridx < 0 || ridx >= IEEE80211_HT_MCS_MASK_LEN)
+		return false;
+
+	/* See whether the selected rate or anything below it is allowed. */
+	for (i = ridx; i >= 0; i--) {
+		for (j = rbit; j >= 0; j--)
+			if (mcs_mask[i] & BIT(j)) {
+				*rate_idx = i * 8 + j;
+				return true;
+			}
+		rbit = 7;
+	}
+
+	/* Try to find a higher rate that would be allowed */
+	ridx = (*rate_idx + 1) / 8;
+	rbit = (*rate_idx + 1) % 8;
+
+	for (i = ridx; i < IEEE80211_HT_MCS_MASK_LEN; i++) {
+		for (j = rbit; j < 8; j++)
+			if (mcs_mask[i] & BIT(j)) {
+				*rate_idx = i * 8 + j;
+				return true;
+			}
+		rbit = 0;
+	}
+	return false;
+}
+
+static bool rate_idx_match_vht_mcs_mask(s8 *rate_idx, u16 *vht_mask)
+{
+	int i, j;
+	int ridx, rbit;
+
+	ridx = *rate_idx >> 4;
+	rbit = *rate_idx & 0xf;
+
+	if (ridx < 0 || ridx >= NL80211_VHT_NSS_MAX)
+		return false;
+
+	/* See whether the selected rate or anything below it is allowed. */
+	for (i = ridx; i >= 0; i--) {
+		for (j = rbit; j >= 0; j--) {
+			if (vht_mask[i] & BIT(j)) {
+				*rate_idx = (i << 4) | j;
+				return true;
+			}
+		}
+		rbit = 15;
+	}
+
+	/* Try to find a higher rate that would be allowed */
+	ridx = (*rate_idx + 1) >> 4;
+	rbit = (*rate_idx + 1) & 0xf;
+
+	for (i = ridx; i < NL80211_VHT_NSS_MAX; i++) {
+		for (j = rbit; j < 16; j++) {
+			if (vht_mask[i] & BIT(j)) {
+				*rate_idx = (i << 4) | j;
+				return true;
+			}
+		}
+		rbit = 0;
+	}
+	return false;
+}
+
+static void rate_idx_match_mask(s8 *rate_idx, u16 *rate_flags,
+				struct ieee80211_supported_band *sband,
+				enum nl80211_chan_width chan_width,
+				u32 mask,
+				u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
+				u16 vht_mask[NL80211_VHT_NSS_MAX])
+{
+	if (*rate_flags & IEEE80211_TX_RC_VHT_MCS) {
+		/* handle VHT rates */
+		if (rate_idx_match_vht_mcs_mask(rate_idx, vht_mask))
+			return;
+
+		*rate_idx = 0;
+		/* keep protection flags */
+		*rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
+				IEEE80211_TX_RC_USE_CTS_PROTECT |
+				IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
+
+		*rate_flags |= IEEE80211_TX_RC_MCS;
+		if (chan_width == NL80211_CHAN_WIDTH_40)
+			*rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
+
+		if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
+			return;
+
+		/* also try the legacy rates. */
+		*rate_flags &= ~(IEEE80211_TX_RC_MCS |
+				 IEEE80211_TX_RC_40_MHZ_WIDTH);
+		if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
+					       mask))
+			return;
+	} else if (*rate_flags & IEEE80211_TX_RC_MCS) {
+		/* handle HT rates */
+		if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
+			return;
+
+		/* also try the legacy rates. */
+		*rate_idx = 0;
+		/* keep protection flags */
+		*rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
+				IEEE80211_TX_RC_USE_CTS_PROTECT |
+				IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
+		if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
+					       mask))
+			return;
+	} else {
+		/* handle legacy rates */
+		if (rate_idx_match_legacy_mask(rate_idx, sband->n_bitrates,
+					       mask))
+			return;
+
+		/* if HT BSS, and we handle a data frame, also try HT rates */
+		switch (chan_width) {
+		case NL80211_CHAN_WIDTH_20_NOHT:
+		case NL80211_CHAN_WIDTH_5:
+		case NL80211_CHAN_WIDTH_10:
+			return;
+		default:
+			break;
+		}
+
+		*rate_idx = 0;
+		/* keep protection flags */
+		*rate_flags &= (IEEE80211_TX_RC_USE_RTS_CTS |
+				IEEE80211_TX_RC_USE_CTS_PROTECT |
+				IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
+
+		*rate_flags |= IEEE80211_TX_RC_MCS;
+
+		if (chan_width == NL80211_CHAN_WIDTH_40)
+			*rate_flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
+
+		if (rate_idx_match_mcs_mask(rate_idx, mcs_mask))
+			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.
+	 */
+}
+
+static void rate_fixup_ratelist(struct ieee80211_vif *vif,
+				struct ieee80211_supported_band *sband,
+				struct ieee80211_tx_info *info,
+				struct ieee80211_tx_rate *rates,
+				int max_rates)
+{
+	struct ieee80211_rate *rate;
+	bool inval = false;
+	int i;
+
+	/*
+	 * Set up the RTS/CTS rate as the fastest basic rate
+	 * that is not faster than the data rate unless there
+	 * is no basic rate slower than the data rate, in which
+	 * case we pick the slowest basic rate
+	 *
+	 * XXX: Should this check all retry rates?
+	 */
+	if (!(rates[0].flags &
+	      (IEEE80211_TX_RC_MCS | IEEE80211_TX_RC_VHT_MCS))) {
+		u32 basic_rates = vif->bss_conf.basic_rates;
+		s8 baserate = basic_rates ? ffs(basic_rates) - 1 : 0;
+
+		rate = &sband->bitrates[rates[0].idx];
+
+		for (i = 0; i < sband->n_bitrates; i++) {
+			/* must be a basic rate */
+			if (!(basic_rates & BIT(i)))
+				continue;
+			/* must not be faster than the data rate */
+			if (sband->bitrates[i].bitrate > rate->bitrate)
+				continue;
+			/* maximum */
+			if (sband->bitrates[baserate].bitrate <
+			     sband->bitrates[i].bitrate)
+				baserate = i;
+		}
+
+		info->control.rts_cts_rate_idx = baserate;
+	}
+
+	for (i = 0; i < max_rates; i++) {
+		/*
+		 * make sure there's no valid rate following
+		 * an invalid one, just in case drivers don't
+		 * take the API seriously to stop at -1.
+		 */
+		if (inval) {
+			rates[i].idx = -1;
+			continue;
+		}
+		if (rates[i].idx < 0) {
+			inval = true;
+			continue;
+		}
+
+		/*
+		 * For now assume MCS is already set up correctly, this
+		 * needs to be fixed.
+		 */
+		if (rates[i].flags & IEEE80211_TX_RC_MCS) {
+			WARN_ON(rates[i].idx > 76);
+
+			if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
+			    info->control.use_cts_prot)
+				rates[i].flags |=
+					IEEE80211_TX_RC_USE_CTS_PROTECT;
+			continue;
+		}
+
+		if (rates[i].flags & IEEE80211_TX_RC_VHT_MCS) {
+			WARN_ON(ieee80211_rate_get_vht_mcs(&rates[i]) > 9);
+			continue;
+		}
+
+		/* set up RTS protection if desired */
+		if (info->control.use_rts) {
+			rates[i].flags |= IEEE80211_TX_RC_USE_RTS_CTS;
+			info->control.use_cts_prot = false;
+		}
+
+		/* RC is busted */
+		if (WARN_ON_ONCE(rates[i].idx >= sband->n_bitrates)) {
+			rates[i].idx = -1;
+			continue;
+		}
+
+		rate = &sband->bitrates[rates[i].idx];
+
+		/* set up short preamble */
+		if (info->control.short_preamble &&
+		    rate->flags & IEEE80211_RATE_SHORT_PREAMBLE)
+			rates[i].flags |= IEEE80211_TX_RC_USE_SHORT_PREAMBLE;
+
+		/* set up G protection */
+		if (!(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) &&
+		    info->control.use_cts_prot &&
+		    rate->flags & IEEE80211_RATE_ERP_G)
+			rates[i].flags |= IEEE80211_TX_RC_USE_CTS_PROTECT;
+	}
+}
+
+
+static void rate_control_fill_sta_table(struct ieee80211_sta *sta,
+					struct ieee80211_tx_info *info,
+					struct ieee80211_tx_rate *rates,
+					int max_rates)
+{
+	struct ieee80211_sta_rates *ratetbl = NULL;
+	int i;
+
+	if (sta && !info->control.skip_table)
+		ratetbl = rcu_dereference(sta->rates);
+
+	/* Fill remaining rate slots with data from the sta rate table. */
+	max_rates = min_t(int, max_rates, IEEE80211_TX_RATE_TABLE_SIZE);
+	for (i = 0; i < max_rates; i++) {
+		if (i < ARRAY_SIZE(info->control.rates) &&
+		    info->control.rates[i].idx >= 0 &&
+		    info->control.rates[i].count) {
+			if (rates != info->control.rates)
+				rates[i] = info->control.rates[i];
+		} else if (ratetbl) {
+			rates[i].idx = ratetbl->rate[i].idx;
+			rates[i].flags = ratetbl->rate[i].flags;
+			if (info->control.use_rts)
+				rates[i].count = ratetbl->rate[i].count_rts;
+			else if (info->control.use_cts_prot)
+				rates[i].count = ratetbl->rate[i].count_cts;
+			else
+				rates[i].count = ratetbl->rate[i].count;
+		} else {
+			rates[i].idx = -1;
+			rates[i].count = 0;
+		}
+
+		if (rates[i].idx < 0 || !rates[i].count)
+			break;
+	}
+}
+
+static bool rate_control_cap_mask(struct ieee80211_sub_if_data *sdata,
+				  struct ieee80211_supported_band *sband,
+				  struct ieee80211_sta *sta, u32 *mask,
+				  u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
+				  u16 vht_mask[NL80211_VHT_NSS_MAX])
+{
+	u32 i, flags;
+
+	*mask = sdata->rc_rateidx_mask[sband->band];
+	flags = ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef);
+	for (i = 0; i < sband->n_bitrates; i++) {
+		if ((flags & sband->bitrates[i].flags) != flags)
+			*mask &= ~BIT(i);
+	}
+
+	if (*mask == (1 << sband->n_bitrates) - 1 &&
+	    !sdata->rc_has_mcs_mask[sband->band] &&
+	    !sdata->rc_has_vht_mcs_mask[sband->band])
+		return false;
+
+	if (sdata->rc_has_mcs_mask[sband->band])
+		memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[sband->band],
+		       IEEE80211_HT_MCS_MASK_LEN);
+	else
+		memset(mcs_mask, 0xff, IEEE80211_HT_MCS_MASK_LEN);
+
+	if (sdata->rc_has_vht_mcs_mask[sband->band])
+		memcpy(vht_mask, sdata->rc_rateidx_vht_mcs_mask[sband->band],
+		       sizeof(u16) * NL80211_VHT_NSS_MAX);
+	else
+		memset(vht_mask, 0xff, sizeof(u16) * NL80211_VHT_NSS_MAX);
+
+	if (sta) {
+		__le16 sta_vht_cap;
+		u16 sta_vht_mask[NL80211_VHT_NSS_MAX];
+
+		/* Filter out rates that the STA does not support */
+		*mask &= sta->supp_rates[sband->band];
+		for (i = 0; i < IEEE80211_HT_MCS_MASK_LEN; i++)
+			mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i];
+
+		sta_vht_cap = sta->vht_cap.vht_mcs.rx_mcs_map;
+		ieee80211_get_vht_mask_from_cap(sta_vht_cap, sta_vht_mask);
+		for (i = 0; i < NL80211_VHT_NSS_MAX; i++)
+			vht_mask[i] &= sta_vht_mask[i];
+	}
+
+	return true;
+}
+
+static void
+rate_control_apply_mask_ratetbl(struct sta_info *sta,
+				struct ieee80211_supported_band *sband,
+				struct ieee80211_sta_rates *rates)
+{
+	int i;
+	u32 mask;
+	u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
+	u16 vht_mask[NL80211_VHT_NSS_MAX];
+	enum nl80211_chan_width chan_width;
+
+	if (!rate_control_cap_mask(sta->sdata, sband, &sta->sta, &mask,
+				   mcs_mask, vht_mask))
+		return;
+
+	chan_width = sta->sdata->vif.bss_conf.chandef.width;
+	for (i = 0; i < IEEE80211_TX_RATE_TABLE_SIZE; i++) {
+		if (rates->rate[i].idx < 0)
+			break;
+
+		rate_idx_match_mask(&rates->rate[i].idx, &rates->rate[i].flags,
+				    sband, chan_width, mask, mcs_mask,
+				    vht_mask);
+	}
+}
+
+static void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata,
+				    struct ieee80211_sta *sta,
+				    struct ieee80211_supported_band *sband,
+				    struct ieee80211_tx_rate *rates,
+				    int max_rates)
+{
+	enum nl80211_chan_width chan_width;
+	u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
+	u32 mask;
+	u16 rate_flags, vht_mask[NL80211_VHT_NSS_MAX];
+	int i;
+
+	/*
+	 * 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.
+	 */
+	if (!rate_control_cap_mask(sdata, sband, sta, &mask, mcs_mask,
+				   vht_mask))
+		return;
+
+	/*
+	 * Make sure the rate index selected for each TX rate is
+	 * included in the configured mask and change the rate indexes
+	 * if needed.
+	 */
+	chan_width = sdata->vif.bss_conf.chandef.width;
+	for (i = 0; i < max_rates; i++) {
+		/* Skip invalid rates */
+		if (rates[i].idx < 0)
+			break;
+
+		rate_flags = rates[i].flags;
+		rate_idx_match_mask(&rates[i].idx, &rate_flags, sband,
+				    chan_width, mask, mcs_mask, vht_mask);
+		rates[i].flags = rate_flags;
+	}
+}
+
+void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
+			    struct ieee80211_sta *sta,
+			    struct sk_buff *skb,
+			    struct ieee80211_tx_rate *dest,
+			    int max_rates)
+{
+	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+	struct ieee80211_supported_band *sband;
+
+	rate_control_fill_sta_table(sta, info, dest, max_rates);
+
+	if (!vif)
+		return;
+
+	sdata = vif_to_sdata(vif);
+	sband = sdata->local->hw.wiphy->bands[info->band];
+
+	if (ieee80211_is_data(hdr->frame_control))
+		rate_control_apply_mask(sdata, sta, sband, dest, max_rates);
+
+	if (dest[0].idx < 0)
+		__rate_control_send_low(&sdata->local->hw, sband, sta, info,
+					sdata->rc_rateidx_mask[info->band]);
+
+	if (sta)
+		rate_fixup_ratelist(vif, sband, info, dest, max_rates);
+}
+EXPORT_SYMBOL(ieee80211_get_tx_rates);
+
+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;
+
+	if (sta && test_sta_flag(sta, WLAN_STA_RATE_CONTROL)) {
+		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 = 0;
+	}
+
+	if (ieee80211_hw_check(&sdata->local->hw, HAS_RATE_CONTROL))
+		return;
+
+	if (ista) {
+		spin_lock_bh(&sta->rate_ctrl_lock);
+		ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
+		spin_unlock_bh(&sta->rate_ctrl_lock);
+	} else {
+		ref->ops->get_rate(ref->priv, NULL, NULL, txrc);
+	}
+
+	if (ieee80211_hw_check(&sdata->local->hw, SUPPORTS_RC_TABLE))
+		return;
+
+	ieee80211_get_tx_rates(&sdata->vif, ista, txrc->skb,
+			       info->control.rates,
+			       ARRAY_SIZE(info->control.rates));
+}
+
+int rate_control_set_rates(struct ieee80211_hw *hw,
+			   struct ieee80211_sta *pubsta,
+			   struct ieee80211_sta_rates *rates)
+{
+	struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
+	struct ieee80211_sta_rates *old;
+	struct ieee80211_supported_band *sband;
+
+	sband = ieee80211_get_sband(sta->sdata);
+	if (!sband)
+		return -EINVAL;
+	rate_control_apply_mask_ratetbl(sta, sband, rates);
+	/*
+	 * mac80211 guarantees that this function will not be called
+	 * concurrently, so the following RCU access is safe, even without
+	 * extra locking. This can not be checked easily, so we just set
+	 * the condition to true.
+	 */
+	old = rcu_dereference_protected(pubsta->rates, true);
+	rcu_assign_pointer(pubsta->rates, rates);
+	if (old)
+		kfree_rcu(old, rcu_head);
+
+	if (sta->uploaded)
+		drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
+
+	ieee80211_sta_set_expected_throughput(pubsta, sta_get_expected_throughput(sta));
+
+	return 0;
+}
+EXPORT_SYMBOL(rate_control_set_rates);
+
+int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
+				 const char *name)
+{
+	struct rate_control_ref *ref;
+
+	ASSERT_RTNL();
+
+	if (local->open_count)
+		return -EBUSY;
+
+	if (ieee80211_hw_check(&local->hw, HAS_RATE_CONTROL)) {
+		if (WARN_ON(!local->ops->set_rts_threshold))
+			return -EINVAL;
+		return 0;
+	}
+
+	ref = rate_control_alloc(name, local);
+	if (!ref) {
+		wiphy_warn(local->hw.wiphy,
+			   "Failed to select rate control algorithm\n");
+		return -ENOENT;
+	}
+
+	WARN_ON(local->rate_ctrl);
+	local->rate_ctrl = ref;
+
+	wiphy_debug(local->hw.wiphy, "Selected rate control algorithm '%s'\n",
+		    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_free(local, ref);
+}