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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/mac80211/rate.c
Initial import
Diffstat (limited to 'net/mac80211/rate.c')
-rw-r--r--net/mac80211/rate.c764
1 files changed, 764 insertions, 0 deletions
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
new file mode 100644
index 000000000..d53355b01
--- /dev/null
+++ b/net/mac80211/rate.c
@@ -0,0 +1,764 @@
+/*
+ * 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 <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");
+
+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;
+
+ kparam_block_sysfs_write(ieee80211_default_rc_algo);
+ 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);
+
+ /* 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);
+ kparam_unblock_sysfs_write(ieee80211_default_rc_algo);
+
+ 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->local = local;
+ 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 rate_control_ref *ctrl_ref)
+{
+ 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
+
+ kfree(ctrl_ref);
+}
+
+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 == IEEE80211_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_ON_ONCE(i == sband->n_bitrates);
+
+ 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(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 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(struct ieee80211_tx_rate *rate,
+ u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
+{
+ 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 void rate_idx_match_mask(struct ieee80211_tx_rate *rate,
+ struct ieee80211_supported_band *sband,
+ enum nl80211_chan_width chan_width,
+ u32 mask,
+ u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN])
+{
+ struct ieee80211_tx_rate alt_rate;
+
+ /* handle HT rates */
+ if (rate->flags & IEEE80211_TX_RC_MCS) {
+ if (rate_idx_match_mcs_mask(rate, mcs_mask))
+ return;
+
+ /* also try the legacy rates. */
+ alt_rate.idx = 0;
+ /* keep protection flags */
+ alt_rate.flags = rate->flags &
+ (IEEE80211_TX_RC_USE_RTS_CTS |
+ IEEE80211_TX_RC_USE_CTS_PROTECT |
+ IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
+ alt_rate.count = rate->count;
+ if (rate_idx_match_legacy_mask(&alt_rate,
+ sband->n_bitrates, mask)) {
+ *rate = alt_rate;
+ return;
+ }
+ } else if (!(rate->flags & IEEE80211_TX_RC_VHT_MCS)) {
+ /* handle legacy rates */
+ if (rate_idx_match_legacy_mask(rate, 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;
+ }
+
+ alt_rate.idx = 0;
+ /* keep protection flags */
+ alt_rate.flags = rate->flags &
+ (IEEE80211_TX_RC_USE_RTS_CTS |
+ IEEE80211_TX_RC_USE_CTS_PROTECT |
+ IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
+ alt_rate.count = rate->count;
+
+ alt_rate.flags |= IEEE80211_TX_RC_MCS;
+
+ if (chan_width == NL80211_CHAN_WIDTH_40)
+ alt_rate.flags |= IEEE80211_TX_RC_40_MHZ_WIDTH;
+
+ if (rate_idx_match_mcs_mask(&alt_rate, mcs_mask)) {
+ *rate = alt_rate;
+ 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 void rate_control_apply_mask(struct ieee80211_sub_if_data *sdata,
+ struct ieee80211_sta *sta,
+ struct ieee80211_supported_band *sband,
+ struct ieee80211_tx_info *info,
+ struct ieee80211_tx_rate *rates,
+ int max_rates)
+{
+ enum nl80211_chan_width chan_width;
+ u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
+ bool has_mcs_mask;
+ u32 mask;
+ u32 rate_flags;
+ 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.
+ */
+ mask = sdata->rc_rateidx_mask[info->band];
+ has_mcs_mask = sdata->rc_has_mcs_mask[info->band];
+ rate_flags =
+ ieee80211_chandef_rate_flags(&sdata->vif.bss_conf.chandef);
+ for (i = 0; i < sband->n_bitrates; i++)
+ if ((rate_flags & sband->bitrates[i].flags) != rate_flags)
+ mask &= ~BIT(i);
+
+ if (mask == (1 << sband->n_bitrates) - 1 && !has_mcs_mask)
+ return;
+
+ if (has_mcs_mask)
+ memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[info->band],
+ sizeof(mcs_mask));
+ else
+ memset(mcs_mask, 0xff, sizeof(mcs_mask));
+
+ if (sta) {
+ /* Filter out rates that the STA does not support */
+ mask &= sta->supp_rates[info->band];
+ for (i = 0; i < sizeof(mcs_mask); i++)
+ mcs_mask[i] &= sta->ht_cap.mcs.rx_mask[i];
+ }
+
+ /*
+ * 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_idx_match_mask(&rates[i], sband, chan_width, mask,
+ mcs_mask);
+ }
+}
+
+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, info, 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 (sdata->local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL)
+ return;
+
+ ref->ops->get_rate(ref->priv, ista, priv_sta, txrc);
+
+ if (sdata->local->hw.flags & IEEE80211_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;
+
+ /*
+ * 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);
+
+ drv_sta_rate_tbl_update(hw_to_local(hw), sta->sdata, pubsta);
+
+ 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 (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) {
+ 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(ref);
+}
+