tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005-2006, Devicescape Software, Inc.
4 * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <linux/kernel.h>
12#include "ieee80211_rate.h"
13#include "ieee80211_i.h"
14
15struct rate_control_alg {
16 struct list_head list;
17 struct rate_control_ops *ops;
18};
19
20static LIST_HEAD(rate_ctrl_algs);
21static DEFINE_MUTEX(rate_ctrl_mutex);
22
23int ieee80211_rate_control_register(struct rate_control_ops *ops)
24{
25 struct rate_control_alg *alg;
26
27 alg = kzalloc(sizeof(*alg), GFP_KERNEL);
28 if (alg == NULL) {
29 return -ENOMEM;
30 }
31 alg->ops = ops;
32
33 mutex_lock(&rate_ctrl_mutex);
34 list_add_tail(&alg->list, &rate_ctrl_algs);
35 mutex_unlock(&rate_ctrl_mutex);
36
37 return 0;
38}
39EXPORT_SYMBOL(ieee80211_rate_control_register);
40
41void ieee80211_rate_control_unregister(struct rate_control_ops *ops)
42{
43 struct rate_control_alg *alg;
44
45 mutex_lock(&rate_ctrl_mutex);
46 list_for_each_entry(alg, &rate_ctrl_algs, list) {
47 if (alg->ops == ops) {
48 list_del(&alg->list);
49 break;
50 }
51 }
52 mutex_unlock(&rate_ctrl_mutex);
53 kfree(alg);
54}
55EXPORT_SYMBOL(ieee80211_rate_control_unregister);
56
57static struct rate_control_ops *
58ieee80211_try_rate_control_ops_get(const char *name)
59{
60 struct rate_control_alg *alg;
61 struct rate_control_ops *ops = NULL;
62
63 mutex_lock(&rate_ctrl_mutex);
64 list_for_each_entry(alg, &rate_ctrl_algs, list) {
65 if (!name || !strcmp(alg->ops->name, name))
66 if (try_module_get(alg->ops->module)) {
67 ops = alg->ops;
68 break;
69 }
70 }
71 mutex_unlock(&rate_ctrl_mutex);
72 return ops;
73}
74
75/* Get the rate control algorithm. If `name' is NULL, get the first
76 * available algorithm. */
77static struct rate_control_ops *
78ieee80211_rate_control_ops_get(const char *name)
79{
80 struct rate_control_ops *ops;
81
82 ops = ieee80211_try_rate_control_ops_get(name);
83 if (!ops) {
84 request_module("rc80211_%s", name ? name : "default");
85 ops = ieee80211_try_rate_control_ops_get(name);
86 }
87 return ops;
88}
89
90static void ieee80211_rate_control_ops_put(struct rate_control_ops *ops)
91{
92 module_put(ops->module);
93}
94
95struct rate_control_ref *rate_control_alloc(const char *name,
96 struct ieee80211_local *local)
97{
98 struct rate_control_ref *ref;
99
100 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
101 if (!ref)
102 goto fail_ref;
103 kref_init(&ref->kref);
104 ref->ops = ieee80211_rate_control_ops_get(name);
105 if (!ref->ops)
106 goto fail_ops;
107 ref->priv = ref->ops->alloc(local);
108 if (!ref->priv)
109 goto fail_priv;
110 return ref;
111
112fail_priv:
113 ieee80211_rate_control_ops_put(ref->ops);
114fail_ops:
115 kfree(ref);
116fail_ref:
117 return NULL;
118}
119
120static void rate_control_release(struct kref *kref)
121{
122 struct rate_control_ref *ctrl_ref;
123
124 ctrl_ref = container_of(kref, struct rate_control_ref, kref);
125 ctrl_ref->ops->free(ctrl_ref->priv);
126 ieee80211_rate_control_ops_put(ctrl_ref->ops);
127 kfree(ctrl_ref);
128}
129
130struct rate_control_ref *rate_control_get(struct rate_control_ref *ref)
131{
132 kref_get(&ref->kref);
133 return ref;
134}
135
136void rate_control_put(struct rate_control_ref *ref)
137{
138 kref_put(&ref->kref, rate_control_release);
139}