From a80f7c0b088187c8471b441d461e937991870661 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 23 Dec 2009 13:15:32 +0100 Subject: [PATCH] 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 Signed-off-by: John W. Linville --- drivers/net/wireless/mac80211_hwsim.c | 11 +++++++++++ include/net/mac80211.h | 5 +++++ net/mac80211/driver-ops.h | 7 +++++++ net/mac80211/driver-trace.h | 21 +++++++++++++++++++++ net/mac80211/iface.c | 2 ++ net/mac80211/scan.c | 13 +++++++++++-- 6 files changed, 57 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c index 718a5f198c30..4dee69a38c1d 100644 --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -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, }; diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 494ac69ff477..77ea34b03285 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -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); }; /** diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h index 727e4cf7b8a6..cbe133bcdf34 100644 --- a/net/mac80211/driver-ops.h +++ b/net/mac80211/driver-ops.h @@ -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 */ diff --git a/net/mac80211/driver-trace.h b/net/mac80211/driver-trace.h index 7a849b920165..977cc7528bc6 100644 --- a/net/mac80211/driver-trace.h +++ b/net/mac80211/driver-trace.h @@ -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 diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c index 1ceca14331d4..389dc8d880f3 100644 --- a/net/mac80211/iface.c +++ b/net/mac80211/iface.c @@ -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; } diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c index ae1830056521..d98c45e5528b 100644 --- a/net/mac80211/scan.c +++ b/net/mac80211/scan.c @@ -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; }