/* * 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 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; local->debugfs.rcname = 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(ctrl_ref->local->debugfs.rcname); ctrl_ref->local->debugfs.rcname = NULL; debugfs_remove(ctrl_ref->local->debugfs.rcdir); ctrl_ref->local->debugfs.rcdir = NULL; #endif ieee80211_rate_control_ops_put(ctrl_ref->ops); kfree(ctrl_ref); } 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) { 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 (sta && sdata->force_unicast_rateidx > -1) { info->control.rates[0].idx = sdata->force_unicast_rateidx; } else { ref->ops->get_rate(ref->priv, ista, priv_sta, txrc); info->flags |= IEEE80211_TX_INTFL_RCALGO; } /* * try to enforce the maximum rate the user wanted */ if (sdata->max_ratectrl_rateidx > -1) for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) { if (info->control.rates[i].flags & IEEE80211_TX_RC_MCS) continue; info->control.rates[i].idx = min_t(s8, info->control.rates[i].idx, sdata->max_ratectrl_rateidx); } 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 || netif_running(local->mdev)) return -EBUSY; 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; local->rate_ctrl = NULL; rate_control_put(ref); }