1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
|
/*
* Off-channel operation helpers
*
* Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
* Copyright 2004, Instant802 Networks, Inc.
* Copyright 2005, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
* Copyright 2007, Michael Wu <flamingice@sourmilk.net>
* Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
*
* 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/export.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-trace.h"
/*
* Tell our hardware to disable PS.
* Optionally inform AP that we will go to sleep so that it will buffer
* the frames while we are doing off-channel work. This is optional
* because we *may* be doing work on-operating channel, and want our
* hardware unconditionally awake, but still let the AP send us normal frames.
*/
static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata,
bool tell_ap)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
local->offchannel_ps_enabled = false;
/* FIXME: what to do when local->pspolling is true? */
del_timer_sync(&local->dynamic_ps_timer);
del_timer_sync(&ifmgd->bcn_mon_timer);
del_timer_sync(&ifmgd->conn_mon_timer);
cancel_work_sync(&local->dynamic_ps_enable_work);
if (local->hw.conf.flags & IEEE80211_CONF_PS) {
local->offchannel_ps_enabled = true;
local->hw.conf.flags &= ~IEEE80211_CONF_PS;
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
}
if (tell_ap && (!local->offchannel_ps_enabled ||
!(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK)))
/*
* If power save was enabled, no need to send a nullfunc
* frame because AP knows that we are sleeping. But if the
* hardware is creating the nullfunc frame for power save
* status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not
* enabled) and power save was enabled, the firmware just
* sent a null frame with power save disabled. So we need
* to send a new nullfunc frame to inform the AP that we
* are again sleeping.
*/
ieee80211_send_nullfunc(local, sdata, 1);
}
/* inform AP that we are awake again, unless power save is enabled */
static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
if (!local->ps_sdata)
ieee80211_send_nullfunc(local, sdata, 0);
else if (local->offchannel_ps_enabled) {
/*
* In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware
* will send a nullfunc frame with the powersave bit set
* even though the AP already knows that we are sleeping.
* This could be avoided by sending a null frame with power
* save bit disabled before enabling the power save, but
* this doesn't gain anything.
*
* When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need
* to send a nullfunc frame because AP already knows that
* we are sleeping, let's just enable power save mode in
* hardware.
*/
/* TODO: Only set hardware if CONF_PS changed?
* TODO: Should we set offchannel_ps_enabled to false?
*/
local->hw.conf.flags |= IEEE80211_CONF_PS;
ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
} else if (local->hw.conf.dynamic_ps_timeout > 0) {
/*
* If IEEE80211_CONF_PS was not set and the dynamic_ps_timer
* had been running before leaving the operating channel,
* restart the timer now and send a nullfunc frame to inform
* the AP that we are awake.
*/
ieee80211_send_nullfunc(local, sdata, 0);
mod_timer(&local->dynamic_ps_timer, jiffies +
msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout));
}
ieee80211_sta_reset_beacon_monitor(sdata);
ieee80211_sta_reset_conn_monitor(sdata);
}
void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;
/*
* notify the AP about us leaving the channel and stop all
* STA interfaces.
*/
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (!ieee80211_sdata_running(sdata))
continue;
if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
/* Check to see if we should disable beaconing. */
if (sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_ADHOC ||
sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
ieee80211_bss_info_change_notify(
sdata, BSS_CHANGED_BEACON_ENABLED);
if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
netif_tx_stop_all_queues(sdata->dev);
if (sdata->vif.type == NL80211_IFTYPE_STATION &&
sdata->u.mgd.associated)
ieee80211_offchannel_ps_enable(sdata, true);
}
}
mutex_unlock(&local->iflist_mtx);
}
void ieee80211_offchannel_return(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;
mutex_lock(&local->iflist_mtx);
list_for_each_entry(sdata, &local->interfaces, list) {
if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
if (!ieee80211_sdata_running(sdata))
continue;
/* Tell AP we're back */
if (sdata->vif.type == NL80211_IFTYPE_STATION &&
sdata->u.mgd.associated)
ieee80211_offchannel_ps_disable(sdata);
if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
/*
* This may wake up queues even though the driver
* currently has them stopped. This is not very
* likely, since the driver won't have gotten any
* (or hardly any) new packets while we weren't
* on the right channel, and even if it happens
* it will at most lead to queueing up one more
* packet per queue in mac80211 rather than on
* the interface qdisc.
*/
netif_tx_wake_all_queues(sdata->dev);
}
if (sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_ADHOC ||
sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
ieee80211_bss_info_change_notify(
sdata, BSS_CHANGED_BEACON_ENABLED);
}
mutex_unlock(&local->iflist_mtx);
}
static void ieee80211_hw_roc_start(struct work_struct *work)
{
struct ieee80211_local *local =
container_of(work, struct ieee80211_local, hw_roc_start);
struct ieee80211_sub_if_data *sdata;
mutex_lock(&local->mtx);
if (!local->hw_roc_channel) {
mutex_unlock(&local->mtx);
return;
}
if (local->hw_roc_skb) {
sdata = IEEE80211_DEV_TO_SUB_IF(local->hw_roc_dev);
ieee80211_tx_skb(sdata, local->hw_roc_skb);
local->hw_roc_skb = NULL;
} else {
cfg80211_ready_on_channel(local->hw_roc_dev,
local->hw_roc_cookie,
local->hw_roc_channel,
local->hw_roc_channel_type,
local->hw_roc_duration,
GFP_KERNEL);
}
ieee80211_recalc_idle(local);
mutex_unlock(&local->mtx);
}
void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
{
struct ieee80211_local *local = hw_to_local(hw);
trace_api_ready_on_channel(local);
ieee80211_queue_work(hw, &local->hw_roc_start);
}
EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
static void ieee80211_hw_roc_done(struct work_struct *work)
{
struct ieee80211_local *local =
container_of(work, struct ieee80211_local, hw_roc_done);
mutex_lock(&local->mtx);
if (!local->hw_roc_channel) {
mutex_unlock(&local->mtx);
return;
}
/* was never transmitted */
if (local->hw_roc_skb) {
u64 cookie;
cookie = local->hw_roc_cookie ^ 2;
cfg80211_mgmt_tx_status(local->hw_roc_dev, cookie,
local->hw_roc_skb->data,
local->hw_roc_skb->len, false,
GFP_KERNEL);
kfree_skb(local->hw_roc_skb);
local->hw_roc_skb = NULL;
local->hw_roc_skb_for_status = NULL;
}
if (!local->hw_roc_for_tx)
cfg80211_remain_on_channel_expired(local->hw_roc_dev,
local->hw_roc_cookie,
local->hw_roc_channel,
local->hw_roc_channel_type,
GFP_KERNEL);
local->hw_roc_channel = NULL;
local->hw_roc_cookie = 0;
ieee80211_recalc_idle(local);
mutex_unlock(&local->mtx);
}
void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw)
{
struct ieee80211_local *local = hw_to_local(hw);
trace_api_remain_on_channel_expired(local);
ieee80211_queue_work(hw, &local->hw_roc_done);
}
EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired);
void ieee80211_hw_roc_setup(struct ieee80211_local *local)
{
INIT_WORK(&local->hw_roc_start, ieee80211_hw_roc_start);
INIT_WORK(&local->hw_roc_done, ieee80211_hw_roc_done);
}
|
