From f30221e4ec62d905b56d5e8f7ccab6b406a97cf5 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Thu, 25 Nov 2010 10:02:30 +0100 Subject: [PATCH] mac80211: implement off-channel mgmt TX This implements the new off-channel TX API in mac80211 with a new work item type. The operation doesn't add a new work item when we're on the right channel and there's no wait time so that for example p2p probe responses will be transmitted without delay. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/cfg.c | 93 ++++++++++++++++++++++++++++++++++++-- net/mac80211/ieee80211_i.h | 5 ++ net/mac80211/status.c | 15 +++++- net/mac80211/work.c | 22 +++++++++ 4 files changed, 129 insertions(+), 6 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index aac2d7de828e..db134b500caa 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1551,6 +1551,28 @@ static int ieee80211_cancel_remain_on_channel(struct wiphy *wiphy, return ieee80211_wk_cancel_remain_on_channel(sdata, cookie); } +static enum work_done_result +ieee80211_offchan_tx_done(struct ieee80211_work *wk, struct sk_buff *skb) +{ + /* + * Use the data embedded in the work struct for reporting + * here so if the driver mangled the SKB before dropping + * it (which is the only way we really should get here) + * then we don't report mangled data. + * + * If there was no wait time, then by the time we get here + * the driver will likely not have reported the status yet, + * so in that case userspace will have to deal with it. + */ + + if (wk->offchan_tx.wait && wk->offchan_tx.frame) + cfg80211_mgmt_tx_status(wk->sdata->dev, + (unsigned long) wk->offchan_tx.frame, + wk->ie, wk->ie_len, false, GFP_KERNEL); + + return WORK_DONE_DESTROY; +} + static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct net_device *dev, struct ieee80211_channel *chan, bool offchan, enum nl80211_channel_type channel_type, @@ -1561,20 +1583,22 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct net_device *dev, struct ieee80211_local *local = sdata->local; struct sk_buff *skb; struct sta_info *sta; + struct ieee80211_work *wk; const struct ieee80211_mgmt *mgmt = (void *)buf; u32 flags = IEEE80211_TX_INTFL_NL80211_FRAME_TX | IEEE80211_TX_CTL_REQ_TX_STATUS; - - if (offchan) - return -EOPNOTSUPP; + bool is_offchan = false; /* Check that we are on the requested channel for transmission */ if (chan != local->tmp_channel && chan != local->oper_channel) - return -EBUSY; + is_offchan = true; if (channel_type_valid && (channel_type != local->tmp_channel_type && channel_type != local->_oper_channel_type)) + is_offchan = true; + + if (is_offchan && !offchan) return -EBUSY; switch (sdata->vif.type) { @@ -1608,12 +1632,70 @@ static int ieee80211_mgmt_tx(struct wiphy *wiphy, struct net_device *dev, IEEE80211_SKB_CB(skb)->flags = flags; skb->dev = sdata->dev; - ieee80211_tx_skb(sdata, skb); *cookie = (unsigned long) skb; + + /* + * Can transmit right away if the channel was the + * right one and there's no wait involved... If a + * wait is involved, we might otherwise not be on + * the right channel for long enough! + */ + if (!is_offchan && !wait && !sdata->vif.bss_conf.idle) { + ieee80211_tx_skb(sdata, skb); + return 0; + } + + wk = kzalloc(sizeof(*wk) + len, GFP_KERNEL); + if (!wk) { + kfree_skb(skb); + return -ENOMEM; + } + + wk->type = IEEE80211_WORK_OFFCHANNEL_TX; + wk->chan = chan; + wk->sdata = sdata; + wk->done = ieee80211_offchan_tx_done; + wk->offchan_tx.frame = skb; + wk->offchan_tx.wait = wait; + wk->ie_len = len; + memcpy(wk->ie, buf, len); + + ieee80211_add_work(wk); return 0; } +static int ieee80211_mgmt_tx_cancel_wait(struct wiphy *wiphy, + struct net_device *dev, + u64 cookie) +{ + struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev); + struct ieee80211_local *local = sdata->local; + struct ieee80211_work *wk; + int ret = -ENOENT; + + mutex_lock(&local->mtx); + list_for_each_entry(wk, &local->work_list, list) { + if (wk->sdata != sdata) + continue; + + if (wk->type != IEEE80211_WORK_OFFCHANNEL_TX) + continue; + + if (cookie != (unsigned long) wk->offchan_tx.frame) + continue; + + wk->timeout = jiffies; + + ieee80211_queue_work(&local->hw, &local->work_work); + ret = 0; + break; + } + mutex_unlock(&local->mtx); + + return ret; +} + static void ieee80211_mgmt_frame_register(struct wiphy *wiphy, struct net_device *dev, u16 frame_type, bool reg) @@ -1698,6 +1780,7 @@ struct cfg80211_ops mac80211_config_ops = { .remain_on_channel = ieee80211_remain_on_channel, .cancel_remain_on_channel = ieee80211_cancel_remain_on_channel, .mgmt_tx = ieee80211_mgmt_tx, + .mgmt_tx_cancel_wait = ieee80211_mgmt_tx_cancel_wait, .set_cqm_rssi_config = ieee80211_set_cqm_rssi_config, .mgmt_frame_register = ieee80211_mgmt_frame_register, .set_antenna = ieee80211_set_antenna, diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 5bc0745368fe..66b0b52b828d 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -260,6 +260,7 @@ enum ieee80211_work_type { IEEE80211_WORK_ASSOC_BEACON_WAIT, IEEE80211_WORK_ASSOC, IEEE80211_WORK_REMAIN_ON_CHANNEL, + IEEE80211_WORK_OFFCHANNEL_TX, }; /** @@ -320,6 +321,10 @@ struct ieee80211_work { struct { u32 duration; } remain; + struct { + struct sk_buff *frame; + u32 wait; + } offchan_tx; }; int ie_len; diff --git a/net/mac80211/status.c b/net/mac80211/status.c index bed7e32ed908..4958710a7d92 100644 --- a/net/mac80211/status.c +++ b/net/mac80211/status.c @@ -321,10 +321,23 @@ void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb) msecs_to_jiffies(10)); } - if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) + if (info->flags & IEEE80211_TX_INTFL_NL80211_FRAME_TX) { + struct ieee80211_work *wk; + + rcu_read_lock(); + list_for_each_entry_rcu(wk, &local->work_list, list) { + if (wk->type != IEEE80211_WORK_OFFCHANNEL_TX) + continue; + if (wk->offchan_tx.frame != skb) + continue; + wk->offchan_tx.frame = NULL; + break; + } + rcu_read_unlock(); cfg80211_mgmt_tx_status( skb->dev, (unsigned long) skb, skb->data, skb->len, !!(info->flags & IEEE80211_TX_STAT_ACK), GFP_ATOMIC); + } /* this was a transmitted frame, but now we want to reuse it */ skb_orphan(skb); diff --git a/net/mac80211/work.c b/net/mac80211/work.c index ae344d1ba056..2b5c3f267198 100644 --- a/net/mac80211/work.c +++ b/net/mac80211/work.c @@ -560,6 +560,25 @@ ieee80211_remain_on_channel_timeout(struct ieee80211_work *wk) return WORK_ACT_TIMEOUT; } +static enum work_action __must_check +ieee80211_offchannel_tx(struct ieee80211_work *wk) +{ + if (!wk->started) { + wk->timeout = jiffies + msecs_to_jiffies(wk->offchan_tx.wait); + + /* + * After this, offchan_tx.frame remains but now is no + * longer a valid pointer -- we still need it as the + * cookie for canceling this work. + */ + ieee80211_tx_skb(wk->sdata, wk->offchan_tx.frame); + + return WORK_ACT_NONE; + } + + return WORK_ACT_TIMEOUT; +} + static enum work_action __must_check ieee80211_assoc_beacon_wait(struct ieee80211_work *wk) { @@ -955,6 +974,9 @@ static void ieee80211_work_work(struct work_struct *work) case IEEE80211_WORK_REMAIN_ON_CHANNEL: rma = ieee80211_remain_on_channel_timeout(wk); break; + case IEEE80211_WORK_OFFCHANNEL_TX: + rma = ieee80211_offchannel_tx(wk); + break; case IEEE80211_WORK_ASSOC_BEACON_WAIT: rma = ieee80211_assoc_beacon_wait(wk); break; -- 2.30.2