cregit-Linux how code gets into the kernel

Release 4.8 net/mac80211/rate.c

Directory: net/mac80211
/*
 * 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");


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); }

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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); }

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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; }

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jiri bencjiri benc6548.51%116.67%
johannes bergjohannes berg6246.27%350.00%
cyrill gorcunovcyrill gorcunov64.48%116.67%
yoann padioleauyoann padioleau10.75%116.67%
Total134100.00%6100.00%

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); }

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Total62100.00%3100.00%

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; }

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jiri bencjiri benc7387.95%133.33%
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Total83100.00%3100.00%

/* 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); /* 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); kernel_param_unlock(THIS_MODULE); return ops; }

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stefano briviostefano brivio2426.09%114.29%
rusty russellrusty russell66.52%114.29%
dan streetmandan streetman44.35%114.29%
Total92100.00%7100.00%

#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); }

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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; }

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andres salomonandres salomon10.63%125.00%
Total159100.00%4100.00%


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); }

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jiri bencjiri benc2445.28%125.00%
Total53100.00%4100.00%


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); }

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rajkumar manoharanrajkumar manoharan56.94%150.00%
Total72100.00%2100.00%


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 */ }

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chun-yeow yeohchun-yeow yeoh11.12%133.33%
Total89100.00%3100.00%


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; }

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luis r. rodriguezluis r. rodriguez5324.20%111.11%
andrei otcheretianskiandrei otcheretianski3415.53%222.22%
rajkumar manoharanrajkumar manoharan3013.70%111.11%
johannes bergjohannes berg2210.05%333.33%
felix fietkaufelix fietkau219.59%111.11%
Total219100.00%9100.00%


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; }

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jouni malinenjouni malinen2813.53%114.29%
luis r. rodriguezluis r. rodriguez83.86%114.29%
andrei otcheretianskiandrei otcheretianski41.93%114.29%
Total207100.00%7100.00%

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; }

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lorenzo bianconilorenzo bianconi1010.00%133.33%
Total100100.00%3100.00%


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; }

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dan carpenterdan carpenter10.51%133.33%
Total195100.00%3100.00%


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; }

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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. */ }

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simon wunderlichsimon wunderlich12046.15%225.00%
felix fietkaufelix fietkau145.38%225.00%
jouni malinenjouni malinen41.54%112.50%
johannes bergjohannes berg10.38%112.50%
Total260100.00%8100.00%


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; } }

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mattias nisslermattias nissler143.11%116.67%
johannes bergjohannes berg40.89%233.33%
karl beldankarl beldan10.22%116.67%
Total450100.00%6100.00%


static void rate_control_fill_sta_table(struct ieee80211_sta *sta, struct ieee80211_tx_info *info, struct ieee80211_tx_rate *rates, int max_rates) {