mac80211: introduce flush operation

We've long lacked a good confirmation that frames
have really gone out, e.g. before going off-channel
for a scan. Add a flush() operation that drivers
can implement to provide that confirmation, and use
it in a few places:
 * before scanning sends the nullfunc frames
 * after scanning sends the nullfunc frames, if any
 * when going idle, to send any pending frames

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Johannes Berg 2009-12-23 13:15:32 +01:00 committed by John W. Linville
parent 9607e6b66a
commit a80f7c0b08
6 changed files with 57 additions and 2 deletions

View File

@ -896,6 +896,16 @@ static int mac80211_hwsim_ampdu_action(struct ieee80211_hw *hw,
return 0;
}
static void mac80211_hwsim_flush(struct ieee80211_hw *hw, bool drop)
{
/*
* In this special case, there's nothing we need to
* do because hwsim does transmission synchronously.
* In the future, when it does transmissions via
* userspace, we may need to do something.
*/
}
static const struct ieee80211_ops mac80211_hwsim_ops =
{
@ -912,6 +922,7 @@ static const struct ieee80211_ops mac80211_hwsim_ops =
.conf_tx = mac80211_hwsim_conf_tx,
CFG80211_TESTMODE_CMD(mac80211_hwsim_testmode_cmd)
.ampdu_action = mac80211_hwsim_ampdu_action,
.flush = mac80211_hwsim_flush,
};

View File

@ -1545,6 +1545,10 @@ enum ieee80211_ampdu_mlme_action {
* and need to call wiphy_rfkill_set_hw_state() in the callback.
*
* @testmode_cmd: Implement a cfg80211 test mode command.
*
* @flush: Flush all pending frames from the hardware queue, making sure
* that the hardware queues are empty. If the parameter @drop is set
* to %true, pending frames may be dropped.
*/
struct ieee80211_ops {
int (*tx)(struct ieee80211_hw *hw, struct sk_buff *skb);
@ -1601,6 +1605,7 @@ struct ieee80211_ops {
#ifdef CONFIG_NL80211_TESTMODE
int (*testmode_cmd)(struct ieee80211_hw *hw, void *data, int len);
#endif
void (*flush)(struct ieee80211_hw *hw, bool drop);
};
/**

View File

@ -259,4 +259,11 @@ static inline void drv_rfkill_poll(struct ieee80211_local *local)
if (local->ops->rfkill_poll)
local->ops->rfkill_poll(&local->hw);
}
static inline void drv_flush(struct ieee80211_local *local, bool drop)
{
trace_drv_flush(local, drop);
if (local->ops->flush)
local->ops->flush(&local->hw, drop);
}
#endif /* __MAC80211_DRIVER_OPS */

View File

@ -690,6 +690,27 @@ TRACE_EVENT(drv_ampdu_action,
LOCAL_PR_ARG, VIF_PR_ARG, STA_PR_ARG, __entry->action, __entry->tid, __entry->ret
)
);
TRACE_EVENT(drv_flush,
TP_PROTO(struct ieee80211_local *local, bool drop),
TP_ARGS(local, drop),
TP_STRUCT__entry(
LOCAL_ENTRY
__field(bool, drop)
),
TP_fast_assign(
LOCAL_ASSIGN;
__entry->drop = drop;
),
TP_printk(
LOCAL_PR_FMT " drop:%d",
LOCAL_PR_ARG, __entry->drop
)
);
#endif /* !__MAC80211_DRIVER_TRACE || TRACE_HEADER_MULTI_READ */
#undef TRACE_INCLUDE_PATH

View File

@ -917,6 +917,8 @@ static u32 ieee80211_idle_on(struct ieee80211_local *local)
wiphy_name(local->hw.wiphy));
#endif
drv_flush(local, false);
local->hw.conf.flags |= IEEE80211_CONF_IDLE;
return IEEE80211_CONF_CHANGE_IDLE;
}

View File

@ -418,9 +418,10 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local)
local->next_scan_state = SCAN_DECISION;
local->scan_channel_idx = 0;
drv_flush(local, false);
ieee80211_configure_filter(local);
/* TODO: start scan as soon as all nullfunc frames are ACKed */
ieee80211_queue_delayed_work(&local->hw,
&local->scan_work,
IEEE80211_CHANNEL_TIME);
@ -584,8 +585,16 @@ static void ieee80211_scan_state_leave_oper_channel(struct ieee80211_local *loca
__set_bit(SCAN_OFF_CHANNEL, &local->scanning);
/*
* What if the nullfunc frames didn't arrive?
*/
drv_flush(local, false);
if (local->ops->flush)
*next_delay = 0;
else
*next_delay = HZ / 10;
/* advance to the next channel to be scanned */
*next_delay = HZ / 10;
local->next_scan_state = SCAN_SET_CHANNEL;
}