linux/net/mac80211/agg-tx.c
Johannes Berg 1b67211895 wifi: mac80211: convert A-MPDU work to wiphy work
Convert the A-MPDU work to wiphy work so it holds the
wiphy mutex and we can later guarantee that to drivers.
It might seem that we could run these concurrently for
different stations, but they're all on the ordered
mac80211 workqueue, so this shouldn't matter for that.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2023-09-11 11:27:19 +02:00

1074 lines
31 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* HT handling
*
* Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
* Copyright 2002-2005, Instant802 Networks, Inc.
* Copyright 2005-2006, Devicescape Software, Inc.
* Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
* Copyright 2007, Michael Wu <flamingice@sourmilk.net>
* Copyright 2007-2010, Intel Corporation
* Copyright(c) 2015-2017 Intel Deutschland GmbH
* Copyright (C) 2018 - 2023 Intel Corporation
*/
#include <linux/ieee80211.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "wme.h"
/**
* DOC: TX A-MPDU aggregation
*
* Aggregation on the TX side requires setting the hardware flag
* %IEEE80211_HW_AMPDU_AGGREGATION. The driver will then be handed
* packets with a flag indicating A-MPDU aggregation. The driver
* or device is responsible for actually aggregating the frames,
* as well as deciding how many and which to aggregate.
*
* When TX aggregation is started by some subsystem (usually the rate
* control algorithm would be appropriate) by calling the
* ieee80211_start_tx_ba_session() function, the driver will be
* notified via its @ampdu_action function, with the
* %IEEE80211_AMPDU_TX_START action.
*
* In response to that, the driver is later required to call the
* ieee80211_start_tx_ba_cb_irqsafe() function, which will really
* start the aggregation session after the peer has also responded.
* If the peer responds negatively, the session will be stopped
* again right away. Note that it is possible for the aggregation
* session to be stopped before the driver has indicated that it
* is done setting it up, in which case it must not indicate the
* setup completion.
*
* Also note that, since we also need to wait for a response from
* the peer, the driver is notified of the completion of the
* handshake by the %IEEE80211_AMPDU_TX_OPERATIONAL action to the
* @ampdu_action callback.
*
* Similarly, when the aggregation session is stopped by the peer
* or something calling ieee80211_stop_tx_ba_session(), the driver's
* @ampdu_action function will be called with the action
* %IEEE80211_AMPDU_TX_STOP. In this case, the call must not fail,
* and the driver must later call ieee80211_stop_tx_ba_cb_irqsafe().
* Note that the sta can get destroyed before the BA tear down is
* complete.
*/
static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
const u8 *da, u16 tid,
u8 dialog_token, u16 start_seq_num,
u16 agg_size, u16 timeout)
{
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb;
struct ieee80211_mgmt *mgmt;
u16 capab;
skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
if (!skb)
return;
skb_reserve(skb, local->hw.extra_tx_headroom);
mgmt = skb_put_zero(skb, 24);
memcpy(mgmt->da, da, ETH_ALEN);
memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
if (sdata->vif.type == NL80211_IFTYPE_AP ||
sdata->vif.type == NL80211_IFTYPE_AP_VLAN ||
sdata->vif.type == NL80211_IFTYPE_MESH_POINT)
memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
else if (sdata->vif.type == NL80211_IFTYPE_STATION)
memcpy(mgmt->bssid, sdata->vif.cfg.ap_addr, ETH_ALEN);
else if (sdata->vif.type == NL80211_IFTYPE_ADHOC)
memcpy(mgmt->bssid, sdata->u.ibss.bssid, ETH_ALEN);
mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
IEEE80211_STYPE_ACTION);
skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
mgmt->u.action.category = WLAN_CATEGORY_BACK;
mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
mgmt->u.action.u.addba_req.dialog_token = dialog_token;
capab = IEEE80211_ADDBA_PARAM_AMSDU_MASK;
capab |= IEEE80211_ADDBA_PARAM_POLICY_MASK;
capab |= u16_encode_bits(tid, IEEE80211_ADDBA_PARAM_TID_MASK);
capab |= u16_encode_bits(agg_size, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
mgmt->u.action.u.addba_req.start_seq_num =
cpu_to_le16(start_seq_num << 4);
ieee80211_tx_skb_tid(sdata, skb, tid, -1);
}
void ieee80211_send_bar(struct ieee80211_vif *vif, u8 *ra, u16 tid, u16 ssn)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sk_buff *skb;
struct ieee80211_bar *bar;
u16 bar_control = 0;
skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
if (!skb)
return;
skb_reserve(skb, local->hw.extra_tx_headroom);
bar = skb_put_zero(skb, sizeof(*bar));
bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
IEEE80211_STYPE_BACK_REQ);
memcpy(bar->ra, ra, ETH_ALEN);
memcpy(bar->ta, sdata->vif.addr, ETH_ALEN);
bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
bar_control |= (u16)(tid << IEEE80211_BAR_CTRL_TID_INFO_SHIFT);
bar->control = cpu_to_le16(bar_control);
bar->start_seq_num = cpu_to_le16(ssn);
IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
IEEE80211_TX_CTL_REQ_TX_STATUS;
ieee80211_tx_skb_tid(sdata, skb, tid, -1);
}
EXPORT_SYMBOL(ieee80211_send_bar);
void ieee80211_assign_tid_tx(struct sta_info *sta, int tid,
struct tid_ampdu_tx *tid_tx)
{
lockdep_assert_held(&sta->ampdu_mlme.mtx);
lockdep_assert_held(&sta->lock);
rcu_assign_pointer(sta->ampdu_mlme.tid_tx[tid], tid_tx);
}
/*
* When multiple aggregation sessions on multiple stations
* are being created/destroyed simultaneously, we need to
* refcount the global queue stop caused by that in order
* to not get into a situation where one of the aggregation
* setup or teardown re-enables queues before the other is
* ready to handle that.
*
* These two functions take care of this issue by keeping
* a global "agg_queue_stop" refcount.
*/
static void __acquires(agg_queue)
ieee80211_stop_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
{
int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
/* we do refcounting here, so don't use the queue reason refcounting */
if (atomic_inc_return(&sdata->local->agg_queue_stop[queue]) == 1)
ieee80211_stop_queue_by_reason(
&sdata->local->hw, queue,
IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
false);
__acquire(agg_queue);
}
static void __releases(agg_queue)
ieee80211_wake_queue_agg(struct ieee80211_sub_if_data *sdata, int tid)
{
int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
if (atomic_dec_return(&sdata->local->agg_queue_stop[queue]) == 0)
ieee80211_wake_queue_by_reason(
&sdata->local->hw, queue,
IEEE80211_QUEUE_STOP_REASON_AGGREGATION,
false);
__release(agg_queue);
}
static void
ieee80211_agg_stop_txq(struct sta_info *sta, int tid)
{
struct ieee80211_txq *txq = sta->sta.txq[tid];
struct ieee80211_sub_if_data *sdata;
struct fq *fq;
struct txq_info *txqi;
if (!txq)
return;
txqi = to_txq_info(txq);
sdata = vif_to_sdata(txq->vif);
fq = &sdata->local->fq;
/* Lock here to protect against further seqno updates on dequeue */
spin_lock_bh(&fq->lock);
set_bit(IEEE80211_TXQ_STOP, &txqi->flags);
spin_unlock_bh(&fq->lock);
}
static void
ieee80211_agg_start_txq(struct sta_info *sta, int tid, bool enable)
{
struct ieee80211_txq *txq = sta->sta.txq[tid];
struct txq_info *txqi;
lockdep_assert_held(&sta->ampdu_mlme.mtx);
if (!txq)
return;
txqi = to_txq_info(txq);
if (enable)
set_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
else
clear_bit(IEEE80211_TXQ_AMPDU, &txqi->flags);
clear_bit(IEEE80211_TXQ_STOP, &txqi->flags);
local_bh_disable();
rcu_read_lock();
schedule_and_wake_txq(sta->sdata->local, txqi);
rcu_read_unlock();
local_bh_enable();
}
/*
* splice packets from the STA's pending to the local pending,
* requires a call to ieee80211_agg_splice_finish later
*/
static void __acquires(agg_queue)
ieee80211_agg_splice_packets(struct ieee80211_sub_if_data *sdata,
struct tid_ampdu_tx *tid_tx, u16 tid)
{
struct ieee80211_local *local = sdata->local;
int queue = sdata->vif.hw_queue[ieee80211_ac_from_tid(tid)];
unsigned long flags;
ieee80211_stop_queue_agg(sdata, tid);
if (WARN(!tid_tx,
"TID %d gone but expected when splicing aggregates from the pending queue\n",
tid))
return;
if (!skb_queue_empty(&tid_tx->pending)) {
spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
/* copy over remaining packets */
skb_queue_splice_tail_init(&tid_tx->pending,
&local->pending[queue]);
spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
}
}
static void __releases(agg_queue)
ieee80211_agg_splice_finish(struct ieee80211_sub_if_data *sdata, u16 tid)
{
ieee80211_wake_queue_agg(sdata, tid);
}
static void ieee80211_remove_tid_tx(struct sta_info *sta, int tid)
{
struct tid_ampdu_tx *tid_tx;
lockdep_assert_held(&sta->ampdu_mlme.mtx);
lockdep_assert_held(&sta->lock);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
/*
* When we get here, the TX path will not be lockless any more wrt.
* aggregation, since the OPERATIONAL bit has long been cleared.
* Thus it will block on getting the lock, if it occurs. So if we
* stop the queue now, we will not get any more packets, and any
* that might be being processed will wait for us here, thereby
* guaranteeing that no packets go to the tid_tx pending queue any
* more.
*/
ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
/* future packets must not find the tid_tx struct any more */
ieee80211_assign_tid_tx(sta, tid, NULL);
ieee80211_agg_splice_finish(sta->sdata, tid);
kfree_rcu(tid_tx, rcu_head);
}
int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
enum ieee80211_agg_stop_reason reason)
{
struct ieee80211_local *local = sta->local;
struct tid_ampdu_tx *tid_tx;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.tid = tid,
.buf_size = 0,
.amsdu = false,
.timeout = 0,
.ssn = 0,
};
int ret;
lockdep_assert_held(&sta->ampdu_mlme.mtx);
switch (reason) {
case AGG_STOP_DECLINED:
case AGG_STOP_LOCAL_REQUEST:
case AGG_STOP_PEER_REQUEST:
params.action = IEEE80211_AMPDU_TX_STOP_CONT;
break;
case AGG_STOP_DESTROY_STA:
params.action = IEEE80211_AMPDU_TX_STOP_FLUSH;
break;
default:
WARN_ON_ONCE(1);
return -EINVAL;
}
spin_lock_bh(&sta->lock);
/* free struct pending for start, if present */
tid_tx = sta->ampdu_mlme.tid_start_tx[tid];
kfree(tid_tx);
sta->ampdu_mlme.tid_start_tx[tid] = NULL;
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
if (!tid_tx) {
spin_unlock_bh(&sta->lock);
return -ENOENT;
}
/*
* if we're already stopping ignore any new requests to stop
* unless we're destroying it in which case notify the driver
*/
if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
spin_unlock_bh(&sta->lock);
if (reason != AGG_STOP_DESTROY_STA)
return -EALREADY;
params.action = IEEE80211_AMPDU_TX_STOP_FLUSH_CONT;
ret = drv_ampdu_action(local, sta->sdata, &params);
WARN_ON_ONCE(ret);
return 0;
}
if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
/* not even started yet! */
ieee80211_assign_tid_tx(sta, tid, NULL);
spin_unlock_bh(&sta->lock);
kfree_rcu(tid_tx, rcu_head);
return 0;
}
set_bit(HT_AGG_STATE_STOPPING, &tid_tx->state);
ieee80211_agg_stop_txq(sta, tid);
spin_unlock_bh(&sta->lock);
ht_dbg(sta->sdata, "Tx BA session stop requested for %pM tid %u\n",
sta->sta.addr, tid);
del_timer_sync(&tid_tx->addba_resp_timer);
del_timer_sync(&tid_tx->session_timer);
/*
* After this packets are no longer handed right through
* to the driver but are put onto tid_tx->pending instead,
* with locking to ensure proper access.
*/
clear_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
/*
* There might be a few packets being processed right now (on
* another CPU) that have already gotten past the aggregation
* check when it was still OPERATIONAL and consequently have
* IEEE80211_TX_CTL_AMPDU set. In that case, this code might
* call into the driver at the same time or even before the
* TX paths calls into it, which could confuse the driver.
*
* Wait for all currently running TX paths to finish before
* telling the driver. New packets will not go through since
* the aggregation session is no longer OPERATIONAL.
*/
if (!local->in_reconfig)
synchronize_net();
tid_tx->stop_initiator = reason == AGG_STOP_PEER_REQUEST ?
WLAN_BACK_RECIPIENT :
WLAN_BACK_INITIATOR;
tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
ret = drv_ampdu_action(local, sta->sdata, &params);
/* HW shall not deny going back to legacy */
if (WARN_ON(ret)) {
/*
* We may have pending packets get stuck in this case...
* Not bothering with a workaround for now.
*/
}
/*
* In the case of AGG_STOP_DESTROY_STA, the driver won't
* necessarily call ieee80211_stop_tx_ba_cb(), so this may
* seem like we can leave the tid_tx data pending forever.
* This is true, in a way, but "forever" is only until the
* station struct is actually destroyed. In the meantime,
* leaving it around ensures that we don't transmit packets
* to the driver on this TID which might confuse it.
*/
return 0;
}
/*
* After sending add Block Ack request we activated a timer until
* add Block Ack response will arrive from the recipient.
* If this timer expires sta_addba_resp_timer_expired will be executed.
*/
static void sta_addba_resp_timer_expired(struct timer_list *t)
{
struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, addba_resp_timer);
struct sta_info *sta = tid_tx->sta;
u8 tid = tid_tx->tid;
/* check if the TID waits for addBA response */
if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state)) {
ht_dbg(sta->sdata,
"timer expired on %pM tid %d not expecting addBA response\n",
sta->sta.addr, tid);
return;
}
ht_dbg(sta->sdata, "addBA response timer expired on %pM tid %d\n",
sta->sta.addr, tid);
ieee80211_stop_tx_ba_session(&sta->sta, tid);
}
static void ieee80211_send_addba_with_timeout(struct sta_info *sta,
struct tid_ampdu_tx *tid_tx)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sta->local;
u8 tid = tid_tx->tid;
u16 buf_size;
if (WARN_ON_ONCE(test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state)))
return;
lockdep_assert_held(&sta->ampdu_mlme.mtx);
/* activate the timer for the recipient's addBA response */
mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
ht_dbg(sdata, "activated addBA response timer on %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
sta->ampdu_mlme.last_addba_req_time[tid] = jiffies;
sta->ampdu_mlme.addba_req_num[tid]++;
spin_unlock_bh(&sta->lock);
if (sta->sta.deflink.he_cap.has_he) {
buf_size = local->hw.max_tx_aggregation_subframes;
} else {
/*
* We really should use what the driver told us it will
* transmit as the maximum, but certain APs (e.g. the
* LinkSys WRT120N with FW v1.0.07 build 002 Jun 18 2012)
* will crash when we use a lower number.
*/
buf_size = IEEE80211_MAX_AMPDU_BUF_HT;
}
/* send AddBA request */
ieee80211_send_addba_request(sdata, sta->sta.addr, tid,
tid_tx->dialog_token, tid_tx->ssn,
buf_size, tid_tx->timeout);
WARN_ON(test_and_set_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state));
}
void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_local *local = sta->local;
struct ieee80211_sub_if_data *sdata;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.action = IEEE80211_AMPDU_TX_START,
.tid = tid,
.buf_size = 0,
.amsdu = false,
.timeout = 0,
};
int ret;
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
/*
* Start queuing up packets for this aggregation session.
* We're going to release them once the driver is OK with
* that.
*/
clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
/*
* Make sure no packets are being processed. This ensures that
* we have a valid starting sequence number and that in-flight
* packets have been flushed out and no packets for this TID
* will go into the driver during the ampdu_action call.
*/
synchronize_net();
sdata = sta->sdata;
params.ssn = sta->tid_seq[tid] >> 4;
ret = drv_ampdu_action(local, sdata, &params);
tid_tx->ssn = params.ssn;
if (ret == IEEE80211_AMPDU_TX_START_DELAY_ADDBA) {
return;
} else if (ret == IEEE80211_AMPDU_TX_START_IMMEDIATE) {
/*
* We didn't send the request yet, so don't need to check
* here if we already got a response, just mark as driver
* ready immediately.
*/
set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state);
} else if (ret) {
if (!sdata)
return;
ht_dbg(sdata,
"BA request denied - HW unavailable for %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
ieee80211_agg_splice_packets(sdata, tid_tx, tid);
ieee80211_assign_tid_tx(sta, tid, NULL);
ieee80211_agg_splice_finish(sdata, tid);
spin_unlock_bh(&sta->lock);
ieee80211_agg_start_txq(sta, tid, false);
kfree_rcu(tid_tx, rcu_head);
return;
}
ieee80211_send_addba_with_timeout(sta, tid_tx);
}
void ieee80211_refresh_tx_agg_session_timer(struct ieee80211_sta *pubsta,
u16 tid)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
struct tid_ampdu_tx *tid_tx;
if (WARN_ON_ONCE(tid >= IEEE80211_NUM_TIDS))
return;
tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
if (!tid_tx)
return;
tid_tx->last_tx = jiffies;
}
EXPORT_SYMBOL(ieee80211_refresh_tx_agg_session_timer);
/*
* After accepting the AddBA Response we activated a timer,
* resetting it after each frame that we send.
*/
static void sta_tx_agg_session_timer_expired(struct timer_list *t)
{
struct tid_ampdu_tx *tid_tx = from_timer(tid_tx, t, session_timer);
struct sta_info *sta = tid_tx->sta;
u8 tid = tid_tx->tid;
unsigned long timeout;
if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
return;
}
timeout = tid_tx->last_tx + TU_TO_JIFFIES(tid_tx->timeout);
if (time_is_after_jiffies(timeout)) {
mod_timer(&tid_tx->session_timer, timeout);
return;
}
ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
sta->sta.addr, tid);
ieee80211_stop_tx_ba_session(&sta->sta, tid);
}
int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
u16 timeout)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
struct tid_ampdu_tx *tid_tx;
int ret = 0;
trace_api_start_tx_ba_session(pubsta, tid);
if (WARN(sta->reserved_tid == tid,
"Requested to start BA session on reserved tid=%d", tid))
return -EINVAL;
if (!pubsta->deflink.ht_cap.ht_supported &&
sta->sdata->vif.bss_conf.chandef.chan->band != NL80211_BAND_6GHZ)
return -EINVAL;
if (WARN_ON_ONCE(!local->ops->ampdu_action))
return -EINVAL;
if ((tid >= IEEE80211_NUM_TIDS) ||
!ieee80211_hw_check(&local->hw, AMPDU_AGGREGATION) ||
ieee80211_hw_check(&local->hw, TX_AMPDU_SETUP_IN_HW))
return -EINVAL;
if (WARN_ON(tid >= IEEE80211_FIRST_TSPEC_TSID))
return -EINVAL;
ht_dbg(sdata, "Open BA session requested for %pM tid %u\n",
pubsta->addr, tid);
if (sdata->vif.type != NL80211_IFTYPE_STATION &&
sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
sdata->vif.type != NL80211_IFTYPE_AP &&
sdata->vif.type != NL80211_IFTYPE_ADHOC)
return -EINVAL;
if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
ht_dbg(sdata,
"BA sessions blocked - Denying BA session request %pM tid %d\n",
sta->sta.addr, tid);
return -EINVAL;
}
if (test_sta_flag(sta, WLAN_STA_MFP) &&
!test_sta_flag(sta, WLAN_STA_AUTHORIZED)) {
ht_dbg(sdata,
"MFP STA not authorized - deny BA session request %pM tid %d\n",
sta->sta.addr, tid);
return -EINVAL;
}
/*
* 802.11n-2009 11.5.1.1: If the initiating STA is an HT STA, is a
* member of an IBSS, and has no other existing Block Ack agreement
* with the recipient STA, then the initiating STA shall transmit a
* Probe Request frame to the recipient STA and shall not transmit an
* ADDBA Request frame unless it receives a Probe Response frame
* from the recipient within dot11ADDBAFailureTimeout.
*
* The probe request mechanism for ADDBA is currently not implemented,
* but we only build up Block Ack session with HT STAs. This information
* is set when we receive a bss info from a probe response or a beacon.
*/
if (sta->sdata->vif.type == NL80211_IFTYPE_ADHOC &&
!sta->sta.deflink.ht_cap.ht_supported) {
ht_dbg(sdata,
"BA request denied - IBSS STA %pM does not advertise HT support\n",
pubsta->addr);
return -EINVAL;
}
spin_lock_bh(&sta->lock);
/* we have tried too many times, receiver does not want A-MPDU */
if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
ret = -EBUSY;
goto err_unlock_sta;
}
/*
* if we have tried more than HT_AGG_BURST_RETRIES times we
* will spread our requests in time to avoid stalling connection
* for too long
*/
if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_BURST_RETRIES &&
time_before(jiffies, sta->ampdu_mlme.last_addba_req_time[tid] +
HT_AGG_RETRIES_PERIOD)) {
ht_dbg(sdata,
"BA request denied - %d failed requests on %pM tid %u\n",
sta->ampdu_mlme.addba_req_num[tid], sta->sta.addr, tid);
ret = -EBUSY;
goto err_unlock_sta;
}
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
/* check if the TID is not in aggregation flow already */
if (tid_tx || sta->ampdu_mlme.tid_start_tx[tid]) {
ht_dbg(sdata,
"BA request denied - session is not idle on %pM tid %u\n",
sta->sta.addr, tid);
ret = -EAGAIN;
goto err_unlock_sta;
}
/* prepare A-MPDU MLME for Tx aggregation */
tid_tx = kzalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
if (!tid_tx) {
ret = -ENOMEM;
goto err_unlock_sta;
}
skb_queue_head_init(&tid_tx->pending);
__set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
tid_tx->timeout = timeout;
tid_tx->sta = sta;
tid_tx->tid = tid;
/* response timer */
timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0);
/* tx timer */
timer_setup(&tid_tx->session_timer,
sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE);
/* assign a dialog token */
sta->ampdu_mlme.dialog_token_allocator++;
tid_tx->dialog_token = sta->ampdu_mlme.dialog_token_allocator;
/*
* Finally, assign it to the start array; the work item will
* collect it and move it to the normal array.
*/
sta->ampdu_mlme.tid_start_tx[tid] = tid_tx;
wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
/* this flow continues off the work */
err_unlock_sta:
spin_unlock_bh(&sta->lock);
return ret;
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
struct sta_info *sta, u16 tid)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_ampdu_params params = {
.sta = &sta->sta,
.action = IEEE80211_AMPDU_TX_OPERATIONAL,
.tid = tid,
.timeout = 0,
.ssn = 0,
};
lockdep_assert_held(&sta->ampdu_mlme.mtx);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
params.buf_size = tid_tx->buf_size;
params.amsdu = tid_tx->amsdu;
ht_dbg(sta->sdata, "Aggregation is on for %pM tid %d\n",
sta->sta.addr, tid);
drv_ampdu_action(local, sta->sdata, &params);
/*
* synchronize with TX path, while splicing the TX path
* should block so it won't put more packets onto pending.
*/
spin_lock_bh(&sta->lock);
ieee80211_agg_splice_packets(sta->sdata, tid_tx, tid);
/*
* Now mark as operational. This will be visible
* in the TX path, and lets it go lock-free in
* the common case.
*/
set_bit(HT_AGG_STATE_OPERATIONAL, &tid_tx->state);
ieee80211_agg_splice_finish(sta->sdata, tid);
spin_unlock_bh(&sta->lock);
ieee80211_agg_start_txq(sta, tid, true);
}
void ieee80211_start_tx_ba_cb(struct sta_info *sta, int tid,
struct tid_ampdu_tx *tid_tx)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
lockdep_assert_held(&sta->ampdu_mlme.mtx);
if (WARN_ON(test_and_set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state)))
return;
if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state) ||
test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state))
return;
if (!test_bit(HT_AGG_STATE_SENT_ADDBA, &tid_tx->state)) {
ieee80211_send_addba_with_timeout(sta, tid_tx);
/* RESPONSE_RECEIVED state whould trigger the flow again */
return;
}
if (test_bit(HT_AGG_STATE_RESPONSE_RECEIVED, &tid_tx->state))
ieee80211_agg_tx_operational(local, sta, tid);
}
static struct tid_ampdu_tx *
ieee80211_lookup_tid_tx(struct ieee80211_sub_if_data *sdata,
const u8 *ra, u16 tid, struct sta_info **sta)
{
struct tid_ampdu_tx *tid_tx;
if (tid >= IEEE80211_NUM_TIDS) {
ht_dbg(sdata, "Bad TID value: tid = %d (>= %d)\n",
tid, IEEE80211_NUM_TIDS);
return NULL;
}
*sta = sta_info_get_bss(sdata, ra);
if (!*sta) {
ht_dbg(sdata, "Could not find station: %pM\n", ra);
return NULL;
}
tid_tx = rcu_dereference((*sta)->ampdu_mlme.tid_tx[tid]);
if (WARN_ON(!tid_tx))
ht_dbg(sdata, "addBA was not requested!\n");
return tid_tx;
}
void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
const u8 *ra, u16 tid)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
struct tid_ampdu_tx *tid_tx;
trace_api_start_tx_ba_cb(sdata, ra, tid);
rcu_read_lock();
tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
if (!tid_tx)
goto out;
set_bit(HT_AGG_STATE_START_CB, &tid_tx->state);
wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
out:
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
enum ieee80211_agg_stop_reason reason)
{
int ret;
mutex_lock(&sta->ampdu_mlme.mtx);
ret = ___ieee80211_stop_tx_ba_session(sta, tid, reason);
mutex_unlock(&sta->ampdu_mlme.mtx);
return ret;
}
int ieee80211_stop_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid)
{
struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
struct ieee80211_sub_if_data *sdata = sta->sdata;
struct ieee80211_local *local = sdata->local;
struct tid_ampdu_tx *tid_tx;
int ret = 0;
trace_api_stop_tx_ba_session(pubsta, tid);
if (!local->ops->ampdu_action)
return -EINVAL;
if (tid >= IEEE80211_NUM_TIDS)
return -EINVAL;
spin_lock_bh(&sta->lock);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
if (!tid_tx) {
ret = -ENOENT;
goto unlock;
}
WARN(sta->reserved_tid == tid,
"Requested to stop BA session on reserved tid=%d", tid);
if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
/* already in progress stopping it */
ret = 0;
goto unlock;
}
set_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state);
wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
unlock:
spin_unlock_bh(&sta->lock);
return ret;
}
EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
void ieee80211_stop_tx_ba_cb(struct sta_info *sta, int tid,
struct tid_ampdu_tx *tid_tx)
{
struct ieee80211_sub_if_data *sdata = sta->sdata;
bool send_delba = false;
bool start_txq = false;
ht_dbg(sdata, "Stopping Tx BA session for %pM tid %d\n",
sta->sta.addr, tid);
spin_lock_bh(&sta->lock);
if (!test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
ht_dbg(sdata,
"unexpected callback to A-MPDU stop for %pM tid %d\n",
sta->sta.addr, tid);
goto unlock_sta;
}
if (tid_tx->stop_initiator == WLAN_BACK_INITIATOR && tid_tx->tx_stop)
send_delba = true;
ieee80211_remove_tid_tx(sta, tid);
start_txq = true;
unlock_sta:
spin_unlock_bh(&sta->lock);
if (start_txq)
ieee80211_agg_start_txq(sta, tid, false);
if (send_delba)
ieee80211_send_delba(sdata, sta->sta.addr, tid,
WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
}
void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_vif *vif,
const u8 *ra, u16 tid)
{
struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
struct tid_ampdu_tx *tid_tx;
trace_api_stop_tx_ba_cb(sdata, ra, tid);
rcu_read_lock();
tid_tx = ieee80211_lookup_tid_tx(sdata, ra, tid, &sta);
if (!tid_tx)
goto out;
set_bit(HT_AGG_STATE_STOP_CB, &tid_tx->state);
wiphy_work_queue(local->hw.wiphy, &sta->ampdu_mlme.work);
out:
rcu_read_unlock();
}
EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
void ieee80211_process_addba_resp(struct ieee80211_local *local,
struct sta_info *sta,
struct ieee80211_mgmt *mgmt,
size_t len)
{
struct tid_ampdu_tx *tid_tx;
struct ieee80211_txq *txq;
u16 capab, tid, buf_size;
bool amsdu;
capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
amsdu = capab & IEEE80211_ADDBA_PARAM_AMSDU_MASK;
tid = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_TID_MASK);
buf_size = u16_get_bits(capab, IEEE80211_ADDBA_PARAM_BUF_SIZE_MASK);
buf_size = min(buf_size, local->hw.max_tx_aggregation_subframes);
txq = sta->sta.txq[tid];
if (!amsdu && txq)
set_bit(IEEE80211_TXQ_NO_AMSDU, &to_txq_info(txq)->flags);
mutex_lock(&sta->ampdu_mlme.mtx);
tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
if (!tid_tx)
goto out;
if (mgmt->u.action.u.addba_resp.dialog_token != tid_tx->dialog_token) {
ht_dbg(sta->sdata, "wrong addBA response token, %pM tid %d\n",
sta->sta.addr, tid);
goto out;
}
del_timer_sync(&tid_tx->addba_resp_timer);
ht_dbg(sta->sdata, "switched off addBA timer for %pM tid %d\n",
sta->sta.addr, tid);
/*
* addba_resp_timer may have fired before we got here, and
* caused WANT_STOP to be set. If the stop then was already
* processed further, STOPPING might be set.
*/
if (test_bit(HT_AGG_STATE_WANT_STOP, &tid_tx->state) ||
test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
ht_dbg(sta->sdata,
"got addBA resp for %pM tid %d but we already gave up\n",
sta->sta.addr, tid);
goto out;
}
/*
* IEEE 802.11-2007 7.3.1.14:
* In an ADDBA Response frame, when the Status Code field
* is set to 0, the Buffer Size subfield is set to a value
* of at least 1.
*/
if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
== WLAN_STATUS_SUCCESS && buf_size) {
if (test_and_set_bit(HT_AGG_STATE_RESPONSE_RECEIVED,
&tid_tx->state)) {
/* ignore duplicate response */
goto out;
}
tid_tx->buf_size = buf_size;
tid_tx->amsdu = amsdu;
if (test_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state))
ieee80211_agg_tx_operational(local, sta, tid);
sta->ampdu_mlme.addba_req_num[tid] = 0;
tid_tx->timeout =
le16_to_cpu(mgmt->u.action.u.addba_resp.timeout);
if (tid_tx->timeout) {
mod_timer(&tid_tx->session_timer,
TU_TO_EXP_TIME(tid_tx->timeout));
tid_tx->last_tx = jiffies;
}
} else {
___ieee80211_stop_tx_ba_session(sta, tid, AGG_STOP_DECLINED);
}
out:
mutex_unlock(&sta->ampdu_mlme.mtx);
}