2 * Copyright 2002-2005, Instant802 Networks, Inc.
3 * Copyright 2005, Devicescape Software, Inc.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License version 2 as
7 * published by the Free Software Foundation.
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/netdevice.h>
13 #include <linux/types.h>
14 #include <linux/slab.h>
15 #include <linux/skbuff.h>
16 #include <linux/compiler.h>
18 #include <net/mac80211.h>
19 #include "ieee80211_i.h"
20 #include "ieee80211_rate.h"
24 /* This is a minimal implementation of TX rate controlling that can be used
25 * as the default when no improved mechanisms are available. */
28 #define RATE_CONTROL_EMERG_DEC 2
29 #define RATE_CONTROL_INTERVAL (HZ / 20)
30 #define RATE_CONTROL_MIN_TX 10
32 MODULE_ALIAS("rc80211_default");
34 static void rate_control_rate_inc(struct ieee80211_local
*local
,
37 struct ieee80211_sub_if_data
*sdata
;
38 struct ieee80211_hw_mode
*mode
;
42 sdata
= IEEE80211_DEV_TO_SUB_IF(sta
->dev
);
43 if (sdata
->bss
&& sdata
->bss
->force_unicast_rateidx
> -1) {
44 /* forced unicast rate - do not change STA rate */
48 mode
= local
->oper_hw_mode
;
49 maxrate
= sdata
->bss
? sdata
->bss
->max_ratectrl_rateidx
: -1;
51 if (i
> mode
->num_rates
)
52 i
= mode
->num_rates
- 2;
54 while (i
+ 1 < mode
->num_rates
) {
56 if (sta
->supp_rates
& BIT(i
) &&
57 mode
->rates
[i
].flags
& IEEE80211_RATE_SUPPORTED
&&
58 (maxrate
< 0 || i
<= maxrate
)) {
66 static void rate_control_rate_dec(struct ieee80211_local
*local
,
69 struct ieee80211_sub_if_data
*sdata
;
70 struct ieee80211_hw_mode
*mode
;
73 sdata
= IEEE80211_DEV_TO_SUB_IF(sta
->dev
);
74 if (sdata
->bss
&& sdata
->bss
->force_unicast_rateidx
> -1) {
75 /* forced unicast rate - do not change STA rate */
79 mode
= local
->oper_hw_mode
;
80 if (i
> mode
->num_rates
)
85 if (sta
->supp_rates
& BIT(i
) &&
86 mode
->rates
[i
].flags
& IEEE80211_RATE_SUPPORTED
) {
94 static struct ieee80211_rate
*
95 rate_control_lowest_rate(struct ieee80211_local
*local
,
96 struct ieee80211_hw_mode
*mode
)
100 for (i
= 0; i
< mode
->num_rates
; i
++) {
101 struct ieee80211_rate
*rate
= &mode
->rates
[i
];
103 if (rate
->flags
& IEEE80211_RATE_SUPPORTED
)
107 printk(KERN_DEBUG
"rate_control_lowest_rate - no supported rates "
109 return &mode
->rates
[0];
113 struct global_rate_control
{
117 struct sta_rate_control
{
118 unsigned long last_rate_change
;
122 unsigned long avg_rate_update
;
126 #ifdef CONFIG_MAC80211_DEBUGFS
127 struct dentry
*tx_avg_rate_sum_dentry
;
128 struct dentry
*tx_avg_rate_num_dentry
;
133 static void rate_control_simple_tx_status(void *priv
, struct net_device
*dev
,
135 struct ieee80211_tx_status
*status
)
137 struct ieee80211_local
*local
= wdev_priv(dev
->ieee80211_ptr
);
138 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) skb
->data
;
139 struct sta_info
*sta
;
140 struct sta_rate_control
*srctrl
;
142 sta
= sta_info_get(local
, hdr
->addr1
);
147 srctrl
= sta
->rate_ctrl_priv
;
148 srctrl
->tx_num_xmit
++;
149 if (status
->excessive_retries
) {
150 sta
->antenna_sel_tx
= sta
->antenna_sel_tx
== 1 ? 2 : 1;
151 sta
->antenna_sel_rx
= sta
->antenna_sel_rx
== 1 ? 2 : 1;
152 if (local
->sta_antenna_sel
== STA_ANTENNA_SEL_SW_CTRL_DEBUG
) {
153 printk(KERN_DEBUG
"%s: " MAC_FMT
" TX antenna --> %d "
154 "RX antenna --> %d (@%lu)\n",
155 dev
->name
, MAC_ARG(hdr
->addr1
),
156 sta
->antenna_sel_tx
, sta
->antenna_sel_rx
, jiffies
);
158 srctrl
->tx_num_failures
++;
159 sta
->tx_retry_failed
++;
160 sta
->tx_num_consecutive_failures
++;
161 sta
->tx_num_mpdu_fail
++;
163 sta
->last_ack_rssi
[0] = sta
->last_ack_rssi
[1];
164 sta
->last_ack_rssi
[1] = sta
->last_ack_rssi
[2];
165 sta
->last_ack_rssi
[2] = status
->ack_signal
;
166 sta
->tx_num_consecutive_failures
= 0;
167 sta
->tx_num_mpdu_ok
++;
169 sta
->tx_retry_count
+= status
->retry_count
;
170 sta
->tx_num_mpdu_fail
+= status
->retry_count
;
172 if (time_after(jiffies
,
173 srctrl
->last_rate_change
+ RATE_CONTROL_INTERVAL
) &&
174 srctrl
->tx_num_xmit
> RATE_CONTROL_MIN_TX
) {
176 srctrl
->last_rate_change
= jiffies
;
178 per_failed
= (100 * sta
->tx_num_mpdu_fail
) /
179 (sta
->tx_num_mpdu_fail
+ sta
->tx_num_mpdu_ok
);
180 /* TODO: calculate average per_failed to make adjusting
181 * parameters easier */
183 if (net_ratelimit()) {
184 printk(KERN_DEBUG
"MPDU fail=%d ok=%d per_failed=%d\n",
185 sta
->tx_num_mpdu_fail
, sta
->tx_num_mpdu_ok
,
190 if (per_failed
> local
->rate_ctrl_num_down
) {
191 rate_control_rate_dec(local
, sta
);
192 } else if (per_failed
< local
->rate_ctrl_num_up
) {
193 rate_control_rate_inc(local
, sta
);
195 srctrl
->tx_avg_rate_sum
+= status
->control
.rate
->rate
;
196 srctrl
->tx_avg_rate_num
++;
197 srctrl
->tx_num_failures
= 0;
198 srctrl
->tx_num_xmit
= 0;
199 } else if (sta
->tx_num_consecutive_failures
>=
200 RATE_CONTROL_EMERG_DEC
) {
201 rate_control_rate_dec(local
, sta
);
204 if (srctrl
->avg_rate_update
+ 60 * HZ
< jiffies
) {
205 srctrl
->avg_rate_update
= jiffies
;
206 if (srctrl
->tx_avg_rate_num
> 0) {
207 #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
208 printk(KERN_DEBUG
"%s: STA " MAC_FMT
" Average rate: "
210 dev
->name
, MAC_ARG(sta
->addr
),
211 srctrl
->tx_avg_rate_sum
/
212 srctrl
->tx_avg_rate_num
,
213 srctrl
->tx_avg_rate_sum
,
214 srctrl
->tx_avg_rate_num
);
215 #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
216 srctrl
->tx_avg_rate_sum
= 0;
217 srctrl
->tx_avg_rate_num
= 0;
225 static struct ieee80211_rate
*
226 rate_control_simple_get_rate(void *priv
, struct net_device
*dev
,
228 struct rate_control_extra
*extra
)
230 struct ieee80211_local
*local
= wdev_priv(dev
->ieee80211_ptr
);
231 struct ieee80211_sub_if_data
*sdata
;
232 struct ieee80211_hdr
*hdr
= (struct ieee80211_hdr
*) skb
->data
;
233 struct ieee80211_hw_mode
*mode
= extra
->mode
;
234 struct sta_info
*sta
;
235 int rateidx
, nonerp_idx
;
238 memset(extra
, 0, sizeof(*extra
));
240 fc
= le16_to_cpu(hdr
->frame_control
);
241 if ((fc
& IEEE80211_FCTL_FTYPE
) != IEEE80211_FTYPE_DATA
||
242 (hdr
->addr1
[0] & 0x01)) {
243 /* Send management frames and broadcast/multicast data using
245 /* TODO: this could probably be improved.. */
246 return rate_control_lowest_rate(local
, mode
);
249 sta
= sta_info_get(local
, hdr
->addr1
);
252 return rate_control_lowest_rate(local
, mode
);
254 sdata
= IEEE80211_DEV_TO_SUB_IF(dev
);
255 if (sdata
->bss
&& sdata
->bss
->force_unicast_rateidx
> -1)
256 sta
->txrate
= sdata
->bss
->force_unicast_rateidx
;
258 rateidx
= sta
->txrate
;
260 if (rateidx
>= mode
->num_rates
)
261 rateidx
= mode
->num_rates
- 1;
263 sta
->last_txrate
= rateidx
;
264 nonerp_idx
= rateidx
;
265 while (nonerp_idx
> 0 &&
266 ((mode
->rates
[nonerp_idx
].flags
& IEEE80211_RATE_ERP
) ||
267 !(mode
->rates
[nonerp_idx
].flags
& IEEE80211_RATE_SUPPORTED
) ||
268 !(sta
->supp_rates
& BIT(nonerp_idx
))))
270 extra
->nonerp
= &mode
->rates
[nonerp_idx
];
274 return &mode
->rates
[rateidx
];
278 static void rate_control_simple_rate_init(void *priv
, void *priv_sta
,
279 struct ieee80211_local
*local
,
280 struct sta_info
*sta
)
282 struct ieee80211_hw_mode
*mode
;
285 mode
= local
->oper_hw_mode
;
286 /* TODO: This routine should consider using RSSI from previous packets
287 * as we need to have IEEE 802.1X auth succeed immediately after assoc..
288 * Until that method is implemented, we will use the lowest supported rate
289 * as a workaround, */
290 for (i
= 0; i
< mode
->num_rates
; i
++) {
291 if ((sta
->supp_rates
& BIT(i
)) &&
292 (mode
->rates
[i
].flags
& IEEE80211_RATE_SUPPORTED
)) {
300 static void * rate_control_simple_alloc(struct ieee80211_local
*local
)
302 struct global_rate_control
*rctrl
;
304 rctrl
= kzalloc(sizeof(*rctrl
), GFP_ATOMIC
);
310 static void rate_control_simple_free(void *priv
)
312 struct global_rate_control
*rctrl
= priv
;
317 static void rate_control_simple_clear(void *priv
)
322 static void * rate_control_simple_alloc_sta(void *priv
, gfp_t gfp
)
324 struct sta_rate_control
*rctrl
;
326 rctrl
= kzalloc(sizeof(*rctrl
), gfp
);
332 static void rate_control_simple_free_sta(void *priv
, void *priv_sta
)
334 struct sta_rate_control
*rctrl
= priv_sta
;
338 #ifdef CONFIG_MAC80211_DEBUGFS
340 static int open_file_generic(struct inode
*inode
, struct file
*file
)
342 file
->private_data
= inode
->i_private
;
346 static ssize_t
sta_tx_avg_rate_sum_read(struct file
*file
,
347 char __user
*userbuf
,
348 size_t count
, loff_t
*ppos
)
350 struct sta_rate_control
*srctrl
= file
->private_data
;
353 sprintf(buf
, "%d\n", srctrl
->tx_avg_rate_sum
);
354 return simple_read_from_buffer(userbuf
, count
, ppos
, buf
, strlen(buf
));
357 static const struct file_operations sta_tx_avg_rate_sum_ops
= {
358 .read
= sta_tx_avg_rate_sum_read
,
359 .open
= open_file_generic
,
362 static ssize_t
sta_tx_avg_rate_num_read(struct file
*file
,
363 char __user
*userbuf
,
364 size_t count
, loff_t
*ppos
)
366 struct sta_rate_control
*srctrl
= file
->private_data
;
369 sprintf(buf
, "%d\n", srctrl
->tx_avg_rate_num
);
370 return simple_read_from_buffer(userbuf
, count
, ppos
, buf
, strlen(buf
));
373 static const struct file_operations sta_tx_avg_rate_num_ops
= {
374 .read
= sta_tx_avg_rate_num_read
,
375 .open
= open_file_generic
,
378 static void rate_control_simple_add_sta_debugfs(void *priv
, void *priv_sta
,
381 struct sta_rate_control
*srctrl
= priv_sta
;
383 srctrl
->tx_avg_rate_num_dentry
=
384 debugfs_create_file("rc_simple_sta_tx_avg_rate_num", 0400,
385 dir
, srctrl
, &sta_tx_avg_rate_num_ops
);
386 srctrl
->tx_avg_rate_sum_dentry
=
387 debugfs_create_file("rc_simple_sta_tx_avg_rate_sum", 0400,
388 dir
, srctrl
, &sta_tx_avg_rate_sum_ops
);
391 static void rate_control_simple_remove_sta_debugfs(void *priv
, void *priv_sta
)
393 struct sta_rate_control
*srctrl
= priv_sta
;
395 debugfs_remove(srctrl
->tx_avg_rate_sum_dentry
);
396 debugfs_remove(srctrl
->tx_avg_rate_num_dentry
);
400 static struct rate_control_ops rate_control_simple
= {
401 .module
= THIS_MODULE
,
403 .tx_status
= rate_control_simple_tx_status
,
404 .get_rate
= rate_control_simple_get_rate
,
405 .rate_init
= rate_control_simple_rate_init
,
406 .clear
= rate_control_simple_clear
,
407 .alloc
= rate_control_simple_alloc
,
408 .free
= rate_control_simple_free
,
409 .alloc_sta
= rate_control_simple_alloc_sta
,
410 .free_sta
= rate_control_simple_free_sta
,
411 #ifdef CONFIG_MAC80211_DEBUGFS
412 .add_sta_debugfs
= rate_control_simple_add_sta_debugfs
,
413 .remove_sta_debugfs
= rate_control_simple_remove_sta_debugfs
,
418 static int __init
rate_control_simple_init(void)
420 return ieee80211_rate_control_register(&rate_control_simple
);
424 static void __exit
rate_control_simple_exit(void)
426 ieee80211_rate_control_unregister(&rate_control_simple
);
430 module_init(rate_control_simple_init
);
431 module_exit(rate_control_simple_exit
);
433 MODULE_DESCRIPTION("Simple rate control algorithm for ieee80211");
434 MODULE_LICENSE("GPL");