android_kernel_motorola_sm6225/net/mac80211/rate.c
Johannes Berg 4b7679a561 mac80211: clean up rate control API
Long awaited, hard work. This patch totally cleans up the rate control
API to remove the requirement to include internal headers outside of
net/mac80211/.

There's one internal use in the PID algorithm left for mesh networking,
we'll have to figure out a way to clean that one up and decide how to
do the peer link evaluation, possibly independent of the rate control
algorithm or via new API.

Additionally, ath9k is left using the cross-inclusion hack for now, we
will add new API where necessary to make this work properly, but right
now I'm not expert enough to do it. It's still off better than before.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2008-09-24 16:18:03 -04:00

296 lines
7 KiB
C

/*
* 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 ieee80211_supported_band *sband,
struct sta_info *sta, struct sk_buff *skb,
struct rate_selection *sel)
{
struct rate_control_ref *ref = sdata->local->rate_ctrl;
void *priv_sta = NULL;
struct ieee80211_sta *ista = NULL;
int i;
sel->rate_idx = -1;
sel->nonerp_idx = -1;
sel->probe_idx = -1;
sel->max_rate_idx = sdata->max_ratectrl_rateidx;
if (sta) {
ista = &sta->sta;
priv_sta = sta->rate_ctrl_priv;
}
if (sta && sdata->force_unicast_rateidx > -1)
sel->rate_idx = sdata->force_unicast_rateidx;
else
ref->ops->get_rate(ref->priv, sband, ista, priv_sta, skb, sel);
if (sdata->max_ratectrl_rateidx > -1 &&
sel->rate_idx > sdata->max_ratectrl_rateidx)
sel->rate_idx = sdata->max_ratectrl_rateidx;
BUG_ON(sel->rate_idx < 0);
/* Select a non-ERP backup rate. */
if (sel->nonerp_idx < 0) {
for (i = 0; i < sband->n_bitrates; i++) {
struct ieee80211_rate *rate = &sband->bitrates[i];
if (sband->bitrates[sel->rate_idx].bitrate < rate->bitrate)
break;
if (rate_supported(ista, sband->band, i) &&
!(rate->flags & IEEE80211_RATE_ERP_G))
sel->nonerp_idx = i;
}
}
}
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);
}