![Cyrill Gorcunov](/assets/img/avatar_default.png)
Fix inappropriate memory freeing in case of requested rate_control_ops was not found. In this case the list head entity is going to be accidentally wasted. Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com> Acked-by: Michael Wu <flamingice@sourmilk.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
200 lines
4.3 KiB
C
200 lines
4.3 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 "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);
|
|
|
|
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. If `name' is NULL, get the first
|
|
* available algorithm. */
|
|
static struct rate_control_ops *
|
|
ieee80211_rate_control_ops_get(const char *name)
|
|
{
|
|
struct rate_control_ops *ops;
|
|
|
|
if (!name)
|
|
name = "simple";
|
|
|
|
ops = ieee80211_try_rate_control_ops_get(name);
|
|
if (!ops) {
|
|
request_module("rc80211_%s", name);
|
|
ops = ieee80211_try_rate_control_ops_get(name);
|
|
}
|
|
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);
|
|
}
|
|
|
|
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);
|
|
}
|