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11#include <linux/kernel.h>
12#include <linux/rtnetlink.h>
13#include "ieee80211_rate.h"
14#include "ieee80211_i.h"
15
16struct rate_control_alg {
17 struct list_head list;
18 struct rate_control_ops *ops;
19};
20
21static LIST_HEAD(rate_ctrl_algs);
22static DEFINE_MUTEX(rate_ctrl_mutex);
23
24int ieee80211_rate_control_register(struct rate_control_ops *ops)
25{
26 struct rate_control_alg *alg;
27
28 if (!ops->name)
29 return -EINVAL;
30
31 mutex_lock(&rate_ctrl_mutex);
32 list_for_each_entry(alg, &rate_ctrl_algs, list) {
33 if (!strcmp(alg->ops->name, ops->name)) {
34
35 WARN_ON(1);
36 mutex_unlock(&rate_ctrl_mutex);
37 return -EALREADY;
38 }
39 }
40
41 alg = kzalloc(sizeof(*alg), GFP_KERNEL);
42 if (alg == NULL) {
43 mutex_unlock(&rate_ctrl_mutex);
44 return -ENOMEM;
45 }
46 alg->ops = ops;
47
48 list_add_tail(&alg->list, &rate_ctrl_algs);
49 mutex_unlock(&rate_ctrl_mutex);
50
51 return 0;
52}
53EXPORT_SYMBOL(ieee80211_rate_control_register);
54
55void ieee80211_rate_control_unregister(struct rate_control_ops *ops)
56{
57 struct rate_control_alg *alg;
58
59 mutex_lock(&rate_ctrl_mutex);
60 list_for_each_entry(alg, &rate_ctrl_algs, list) {
61 if (alg->ops == ops) {
62 list_del(&alg->list);
63 kfree(alg);
64 break;
65 }
66 }
67 mutex_unlock(&rate_ctrl_mutex);
68}
69EXPORT_SYMBOL(ieee80211_rate_control_unregister);
70
71static struct rate_control_ops *
72ieee80211_try_rate_control_ops_get(const char *name)
73{
74 struct rate_control_alg *alg;
75 struct rate_control_ops *ops = NULL;
76
77 if (!name)
78 return NULL;
79
80 mutex_lock(&rate_ctrl_mutex);
81 list_for_each_entry(alg, &rate_ctrl_algs, list) {
82 if (!strcmp(alg->ops->name, name))
83 if (try_module_get(alg->ops->module)) {
84 ops = alg->ops;
85 break;
86 }
87 }
88 mutex_unlock(&rate_ctrl_mutex);
89 return ops;
90}
91
92
93
94static struct rate_control_ops *
95ieee80211_rate_control_ops_get(const char *name)
96{
97 struct rate_control_ops *ops;
98
99 if (!name)
100 name = "simple";
101
102 ops = ieee80211_try_rate_control_ops_get(name);
103 if (!ops) {
104 request_module("rc80211_%s", name);
105 ops = ieee80211_try_rate_control_ops_get(name);
106 }
107 return ops;
108}
109
110static void ieee80211_rate_control_ops_put(struct rate_control_ops *ops)
111{
112 module_put(ops->module);
113}
114
115struct rate_control_ref *rate_control_alloc(const char *name,
116 struct ieee80211_local *local)
117{
118 struct rate_control_ref *ref;
119
120 ref = kmalloc(sizeof(struct rate_control_ref), GFP_KERNEL);
121 if (!ref)
122 goto fail_ref;
123 kref_init(&ref->kref);
124 ref->ops = ieee80211_rate_control_ops_get(name);
125 if (!ref->ops)
126 goto fail_ops;
127 ref->priv = ref->ops->alloc(local);
128 if (!ref->priv)
129 goto fail_priv;
130 return ref;
131
132fail_priv:
133 ieee80211_rate_control_ops_put(ref->ops);
134fail_ops:
135 kfree(ref);
136fail_ref:
137 return NULL;
138}
139
140static void rate_control_release(struct kref *kref)
141{
142 struct rate_control_ref *ctrl_ref;
143
144 ctrl_ref = container_of(kref, struct rate_control_ref, kref);
145 ctrl_ref->ops->free(ctrl_ref->priv);
146 ieee80211_rate_control_ops_put(ctrl_ref->ops);
147 kfree(ctrl_ref);
148}
149
150struct rate_control_ref *rate_control_get(struct rate_control_ref *ref)
151{
152 kref_get(&ref->kref);
153 return ref;
154}
155
156void rate_control_put(struct rate_control_ref *ref)
157{
158 kref_put(&ref->kref, rate_control_release);
159}
160
161int ieee80211_init_rate_ctrl_alg(struct ieee80211_local *local,
162 const char *name)
163{
164 struct rate_control_ref *ref, *old;
165
166 ASSERT_RTNL();
167 if (local->open_count || netif_running(local->mdev))
168 return -EBUSY;
169
170 ref = rate_control_alloc(name, local);
171 if (!ref) {
172 printk(KERN_WARNING "%s: Failed to select rate control "
173 "algorithm\n", wiphy_name(local->hw.wiphy));
174 return -ENOENT;
175 }
176
177 old = local->rate_ctrl;
178 local->rate_ctrl = ref;
179 if (old) {
180 rate_control_put(old);
181 sta_info_flush(local, NULL);
182 }
183
184 printk(KERN_DEBUG "%s: Selected rate control "
185 "algorithm '%s'\n", wiphy_name(local->hw.wiphy),
186 ref->ops->name);
187
188
189 return 0;
190}
191
192void rate_control_deinitialize(struct ieee80211_local *local)
193{
194 struct rate_control_ref *ref;
195
196 ref = local->rate_ctrl;
197 local->rate_ctrl = NULL;
198 rate_control_put(ref);
199}
200
