[ 04/22] mac80211: synchronize scan off/on-channel and PS states

Greg Kroah-Hartman
2013-02-12T20:55:36Z

From: Stanislaw Gruszka <sgruszka@redhat.com>

commit aacde9ee45225f7e0b90960f479aef83c66bfdc0 upstream.

Since:

commit b23b025fe246f3acc2988eb6d400df34c27cb8ae
Author: Ben Greear <greearb@candelatech.com>
Date: Fri Feb 4 11:54:17 2011 -0800

mac80211: Optimize scans on current operating channel.

we do not disable PS while going back to operational channel (on
ieee80211_scan_state_suspend) and deffer that until scan finish.
But since we are allowed to send frames, we can send a frame to AP
without PM bit set, so disable PS on AP side. Then when we switch
to off-channel (in ieee80211_scan_state_resume) we do not enable PS.
Hence we are off-channel with PS disabled, frames are not buffered
by AP.

To fix remove offchannel_ps_disable argument and always enable PS when
going off-channel and disable it when going on-channel, like it was
before.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: CAI Qian <caiqian@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
net/mac80211/ieee80211_i.h | 6 ++----
net/mac80211/offchannel.c | 17 ++++++-----------
net/mac80211/scan.c | 6 +++---
net/mac80211/work.c | 8 +++-----
4 files changed, 14 insertions(+), 23 deletions(-)

--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1169,11 +1169,9 @@ void ieee80211_sched_scan_stopped_work(s
bool ieee80211_cfg_on_oper_channel(struct ieee80211_local *local);
void ieee80211_offchannel_enable_all_ps(struct ieee80211_local *local,
bool tell_ap);
-void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
- bool offchannel_ps_enable);
+void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local);
void ieee80211_offchannel_return(struct ieee80211_local *local,
- bool enable_beaconing,
- bool offchannel_ps_disable);
+ bool enable_beaconing);
void ieee80211_hw_roc_setup(struct ieee80211_local *local);

/* interface handling */
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -102,8 +102,7 @@ static void ieee80211_offchannel_ps_disa
ieee80211_sta_reset_conn_monitor(sdata);
}

-void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local,
- bool offchannel_ps_enable)
+void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;

@@ -128,8 +127,7 @@ void ieee80211_offchannel_stop_vifs(stru

if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
netif_tx_stop_all_queues(sdata->dev);
- if (offchannel_ps_enable &&
- (sdata->vif.type == NL80211_IFTYPE_STATION) &&
+ if (sdata->vif.type == NL80211_IFTYPE_STATION &&
sdata->u.mgd.associated)
ieee80211_offchannel_ps_enable(sdata, true);
}
@@ -155,8 +153,7 @@ void ieee80211_offchannel_enable_all_ps(
}

void ieee80211_offchannel_return(struct ieee80211_local *local,
- bool enable_beaconing,
- bool offchannel_ps_disable)
+ bool enable_beaconing)
{
struct ieee80211_sub_if_data *sdata;

@@ -166,11 +163,9 @@ void ieee80211_offchannel_return(struct
continue;

/* Tell AP we're back */
- if (offchannel_ps_disable &&
- sdata->vif.type == NL80211_IFTYPE_STATION) {
- if (sdata->u.mgd.associated)
- ieee80211_offchannel_ps_disable(sdata);
- }
+ if (sdata->vif.type == NL80211_IFTYPE_STATION &&
+ sdata->u.mgd.associated)
+ ieee80211_offchannel_ps_disable(sdata);

if (sdata->vif.type != NL80211_IFTYPE_MONITOR) {
clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -314,7 +314,7 @@ static void __ieee80211_scan_completed(s
if (on_oper_chan2 && (on_oper_chan != on_oper_chan2))
enable_beacons = true;

- ieee80211_offchannel_return(local, enable_beacons, true);
+ ieee80211_offchannel_return(local, enable_beacons);
}

ieee80211_recalc_idle(local);
@@ -563,7 +563,7 @@ static void ieee80211_scan_state_leave_o
/* PS will already be in off-channel mode,
* we do that once at the beginning of scanning.
*/
- ieee80211_offchannel_stop_vifs(local, false);
+ ieee80211_offchannel_stop_vifs(local);

/*
* What if the nullfunc frames didn't arrive?
@@ -594,7 +594,7 @@ static void ieee80211_scan_state_enter_o
* in off-channel state..will put that back
* on-channel at the end of scanning.
*/
- ieee80211_offchannel_return(local, true, false);
+ ieee80211_offchannel_return(local, true);

*next_delay = HZ / 5;
local->next_scan_state = SCAN_DECISION;
--- a/net/mac80211/work.c
+++ b/net/mac80211/work.c
@@ -973,16 +973,14 @@ static void ieee80211_work_work(struct w
if (on_oper_chan != on_oper_chan2) {
if (on_oper_chan2) {
/* going off oper channel, PS too */
- ieee80211_offchannel_stop_vifs(local,
- true);
+ ieee80211_offchannel_stop_vifs(local);
ieee80211_hw_config(local, 0);
} else {
/* going on channel, but leave PS
* off-channel. */
ieee80211_hw_config(local, 0);
ieee80211_offchannel_return(local,
- true,
- false);
+ true);
}
} else if (tmp_chan_changed)
/* Still off-channel, but on some other
@@ -1085,7 +1083,7 @@ static void ieee80211_work_work(struct w
* beaconing if we were already on-oper-channel
* as a future optimization.
*/
- ieee80211_offchannel_return(local, true, true);
+ ieee80211_offchannel_return(local, true);

/* give connection some time to breathe */
run_again(local, jiffies + HZ/2);