| /* |
| * 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 "ieee80211_rate.h" |
| #include "ieee80211_i.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); |
| } |
| |
| struct rate_control_ref *rate_control_alloc(const char *name, |
| struct ieee80211_local *local) |
| { |
| struct rate_control_ref *ref; |
| |
| ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL); |
| if (!ref) |
| goto fail_ref; |
| kref_init(&ref->kref); |
| ref->ops = ieee80211_rate_control_ops_get(name); |
| if (!ref->ops) |
| goto fail_ops; |
| ref->priv = ref->ops->alloc(local); |
| 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); |
| ieee80211_rate_control_ops_put(ctrl_ref->ops); |
| kfree(ctrl_ref); |
| } |
| |
| void rate_control_get_rate(struct net_device *dev, |
| struct ieee80211_supported_band *sband, |
| struct sk_buff *skb, |
| struct rate_selection *sel) |
| { |
| struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr); |
| struct rate_control_ref *ref = local->rate_ctrl; |
| struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data; |
| struct sta_info *sta = sta_info_get(local, hdr->addr1); |
| int i; |
| |
| memset(sel, 0, sizeof(struct rate_selection)); |
| |
| ref->ops->get_rate(ref->priv, dev, sband, skb, sel); |
| |
| /* Select a non-ERP backup rate. */ |
| if (!sel->nonerp) { |
| for (i = 0; i < sband->n_bitrates; i++) { |
| struct ieee80211_rate *rate = &sband->bitrates[i]; |
| if (sel->rate->bitrate < rate->bitrate) |
| break; |
| |
| if (rate_supported(sta, sband->band, i) && |
| !(rate->flags & IEEE80211_RATE_ERP_G)) |
| sel->nonerp = rate; |
| } |
| } |
| |
| if (sta) |
| sta_info_put(sta); |
| } |
| |
| 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); |
| } |
| |