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-rw-r--r--net/mac80211/rate.c534
1 files changed, 534 insertions, 0 deletions
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
new file mode 100644
index 00000000..3313c117
--- /dev/null
+++ b/net/mac80211/rate.c
@@ -0,0 +1,534 @@
+/*
+ * 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/slab.h>
+#include <linux/module.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;
+
+ 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) {
+ 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);
+ kparam_unblock_sysfs_write(ieee80211_default_rc_algo);
+
+ 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 = 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)
+ goto fail_ref;
+ 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_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
+
+ ieee80211_rate_control_ops_put(ctrl_ref->ops);
+ 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_broadcast(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 inline s8
+rate_lowest_non_cck_index(struct ieee80211_supported_band *sband,
+ struct ieee80211_sta *sta)
+{
+ int i;
+
+ for (i = 0; i < sband->n_bitrates; i++) {
+ struct ieee80211_rate *srate = &sband->bitrates[i];
+ if ((srate->bitrate == 10) || (srate->bitrate == 20) ||
+ (srate->bitrate == 55) || (srate->bitrate == 110))
+ continue;
+
+ if (rate_supported(sta, sband->band, i))
+ return i;
+ }
+
+ /* No matching rate found */
+ return 0;
+}
+
+
+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);
+ struct ieee80211_supported_band *sband = txrc->sband;
+ int mcast_rate;
+
+ if (!sta || !priv_sta || rc_no_data_or_no_ack_use_min(txrc)) {
+ if ((sband->band != IEEE80211_BAND_2GHZ) ||
+ !(info->flags & IEEE80211_TX_CTL_NO_CCK_RATE))
+ info->control.rates[0].idx =
+ rate_lowest_index(txrc->sband, sta);
+ else
+ info->control.rates[0].idx =
+ rate_lowest_non_cck_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->bss) {
+ mcast_rate = txrc->bss_conf->mcast_rate[sband->band];
+ if (mcast_rate > 0) {
+ info->control.rates[0].idx = mcast_rate - 1;
+ return true;
+ }
+
+ rc_send_low_broadcast(&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_tx_rate_control *txrc,
+ 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,
+ txrc->sband->n_bitrates,
+ mask)) {
+ *rate = alt_rate;
+ return;
+ }
+ } else {
+ struct sk_buff *skb = txrc->skb;
+ struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+ __le16 fc;
+
+ /* handle legacy rates */
+ if (rate_idx_match_legacy_mask(rate, txrc->sband->n_bitrates,
+ mask))
+ return;
+
+ /* if HT BSS, and we handle a data frame, also try HT rates */
+ if (txrc->bss_conf->channel_type == NL80211_CHAN_NO_HT)
+ return;
+
+ fc = hdr->frame_control;
+ if (!ieee80211_is_data(fc))
+ return;
+
+ 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 ((txrc->bss_conf->channel_type == NL80211_CHAN_HT40MINUS) ||
+ (txrc->bss_conf->channel_type == NL80211_CHAN_HT40PLUS))
+ 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.
+ */
+}
+
+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;
+ u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN];
+
+ 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);
+
+ /*
+ * 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];
+ memcpy(mcs_mask, sdata->rc_rateidx_mcs_mask[info->band],
+ sizeof(mcs_mask));
+ 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];
+ for (i = 0; i < sizeof(mcs_mask); i++)
+ mcs_mask[i] &= sta->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.
+ */
+ for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
+ /* Skip invalid rates */
+ if (info->control.rates[i].idx < 0)
+ break;
+ rate_idx_match_mask(&info->control.rates[i], txrc,
+ mask, mcs_mask);
+ }
+ }
+
+ BUG_ON(info->control.rates[0].idx < 0);
+}
+
+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);
+}
+
generated by cgit (git 2.34.1) at 2025-02-11 03:01:32 +0000