mac80211: aggregation: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

This removes the tid mapping array and expands the tid structures to
add a pointer back to the station, along with the tid index itself.

Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
[switch tid variables to u8, the valid range is 0-15 at most,
 initialize tid_tx->sta/tid properly]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index 88cc1ae935ead5f1a2b4a46d2d3af3fbf4cefd8d..d444752dbf40789cfb0d93d3d572b6bd04263671 100644 (file)
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -151,21 +151,17 @@ EXPORT_SYMBOL(ieee80211_stop_rx_ba_session);
  * After accepting the AddBA Request we activated a timer,
  * resetting it after each frame that arrives from the originator.
  */
-static void sta_rx_agg_session_timer_expired(unsigned long data)
+static void sta_rx_agg_session_timer_expired(struct timer_list *t)
 {
-       /* not an elegant detour, but there is no choice as the timer passes
-        * only one argument, and various sta_info are needed here, so init
-        * flow in sta_info_create gives the TID as data, while the timer_to_id
-        * array gives the sta through container_of */
-       u8 *ptid = (u8 *)data;
-       u8 *timer_to_id = ptid - *ptid;
-       struct sta_info *sta = container_of(timer_to_id, struct sta_info,
-                                        timer_to_tid[0]);
+       struct tid_ampdu_rx *tid_rx_timer =
+               from_timer(tid_rx_timer, t, session_timer);
+       struct sta_info *sta = tid_rx_timer->sta;
+       u8 tid = tid_rx_timer->tid;
        struct tid_ampdu_rx *tid_rx;
        unsigned long timeout;
 
        rcu_read_lock();
-       tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[*ptid]);
+       tid_rx = rcu_dereference(sta->ampdu_mlme.tid_rx[tid]);
        if (!tid_rx) {
                rcu_read_unlock();
                return;
@@ -180,21 +176,18 @@ static void sta_rx_agg_session_timer_expired(unsigned long data)
        rcu_read_unlock();
 
        ht_dbg(sta->sdata, "RX session timer expired on %pM tid %d\n",
-              sta->sta.addr, (u16)*ptid);
+              sta->sta.addr, tid);
 
-       set_bit(*ptid, sta->ampdu_mlme.tid_rx_timer_expired);
+       set_bit(tid, sta->ampdu_mlme.tid_rx_timer_expired);
        ieee80211_queue_work(&sta->local->hw, &sta->ampdu_mlme.work);
 }
 
-static void sta_rx_agg_reorder_timer_expired(unsigned long data)
+static void sta_rx_agg_reorder_timer_expired(struct timer_list *t)
 {
-       u8 *ptid = (u8 *)data;
-       u8 *timer_to_id = ptid - *ptid;
-       struct sta_info *sta = container_of(timer_to_id, struct sta_info,
-                       timer_to_tid[0]);
+       struct tid_ampdu_rx *tid_rx = from_timer(tid_rx, t, reorder_timer);
 
        rcu_read_lock();
-       ieee80211_release_reorder_timeout(sta, *ptid);
+       ieee80211_release_reorder_timeout(tid_rx->sta, tid_rx->tid);
        rcu_read_unlock();
 }
 
@@ -356,14 +349,12 @@ void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
        spin_lock_init(&tid_agg_rx->reorder_lock);
 
        /* rx timer */
-       setup_deferrable_timer(&tid_agg_rx->session_timer,
-                              sta_rx_agg_session_timer_expired,
-                              (unsigned long)&sta->timer_to_tid[tid]);
+       timer_setup(&tid_agg_rx->session_timer,
+                   sta_rx_agg_session_timer_expired, TIMER_DEFERRABLE);
 
        /* rx reorder timer */
-       setup_timer(&tid_agg_rx->reorder_timer,
-                   sta_rx_agg_reorder_timer_expired,
-                   (unsigned long)&sta->timer_to_tid[tid]);
+       timer_setup(&tid_agg_rx->reorder_timer,
+                   sta_rx_agg_reorder_timer_expired, 0);
 
        /* prepare reordering buffer */
        tid_agg_rx->reorder_buf =
@@ -399,6 +390,8 @@ void ___ieee80211_start_rx_ba_session(struct sta_info *sta,
        tid_agg_rx->auto_seq = auto_seq;
        tid_agg_rx->started = false;
        tid_agg_rx->reorder_buf_filtered = 0;
+       tid_agg_rx->tid = tid;
+       tid_agg_rx->sta = sta;
        status = WLAN_STATUS_SUCCESS;
 
        /* activate it for RX */

diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index bef516ec47f94c19f57da37d80c744bb534deeb4..3680b380e70cfc2e51a3c20a40409a77b6e79809 100644 (file)
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -422,15 +422,12 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
  * 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(unsigned long data)
+static void sta_addba_resp_timer_expired(struct timer_list *t)
 {
-       /* not an elegant detour, but there is no choice as the timer passes
-        * only one argument, and both sta_info and TID are needed, so init
-        * flow in sta_info_create gives the TID as data, while the timer_to_id
-        * array gives the sta through container_of */
-       u16 tid = *(u8 *)data;
-       struct sta_info *sta = container_of((void *)data,
-               struct sta_info, timer_to_tid[tid]);
+       struct tid_ampdu_tx *tid_tx_timer =
+               from_timer(tid_tx_timer, t, addba_resp_timer);
+       struct sta_info *sta = tid_tx_timer->sta;
+       u8 tid = tid_tx_timer->tid;
        struct tid_ampdu_tx *tid_tx;
 
        /* check if the TID waits for addBA response */
@@ -525,21 +522,17 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
  * 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(unsigned long data)
+static void sta_tx_agg_session_timer_expired(struct timer_list *t)
 {
-       /* not an elegant detour, but there is no choice as the timer passes
-        * only one argument, and various sta_info are needed here, so init
-        * flow in sta_info_create gives the TID as data, while the timer_to_id
-        * array gives the sta through container_of */
-       u8 *ptid = (u8 *)data;
-       u8 *timer_to_id = ptid - *ptid;
-       struct sta_info *sta = container_of(timer_to_id, struct sta_info,
-                                        timer_to_tid[0]);
+       struct tid_ampdu_tx *tid_tx_timer =
+               from_timer(tid_tx_timer, t, session_timer);
+       struct sta_info *sta = tid_tx_timer->sta;
+       u8 tid = tid_tx_timer->tid;
        struct tid_ampdu_tx *tid_tx;
        unsigned long timeout;
 
        rcu_read_lock();
-       tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[*ptid]);
+       tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
        if (!tid_tx || test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
                rcu_read_unlock();
                return;
@@ -555,9 +548,9 @@ static void sta_tx_agg_session_timer_expired(unsigned long data)
        rcu_read_unlock();
 
        ht_dbg(sta->sdata, "tx session timer expired on %pM tid %d\n",
-              sta->sta.addr, (u16)*ptid);
+              sta->sta.addr, tid);
 
-       ieee80211_stop_tx_ba_session(&sta->sta, *ptid);
+       ieee80211_stop_tx_ba_session(&sta->sta, tid);
 }
 
 int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
@@ -670,16 +663,15 @@ int ieee80211_start_tx_ba_session(struct ieee80211_sta *pubsta, u16 tid,
        __set_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
 
        tid_tx->timeout = timeout;
+       tid_tx->sta = sta;
+       tid_tx->tid = tid;
 
        /* response timer */
-       setup_timer(&tid_tx->addba_resp_timer,
-                   sta_addba_resp_timer_expired,
-                   (unsigned long)&sta->timer_to_tid[tid]);
+       timer_setup(&tid_tx->addba_resp_timer, sta_addba_resp_timer_expired, 0);
 
        /* tx timer */
-       setup_deferrable_timer(&tid_tx->session_timer,
-                              sta_tx_agg_session_timer_expired,
-                              (unsigned long)&sta->timer_to_tid[tid]);
+       timer_setup(&tid_tx->session_timer,
+                   sta_tx_agg_session_timer_expired, TIMER_DEFERRABLE);
 
        /* assign a dialog token */
        sta->ampdu_mlme.dialog_token_allocator++;

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 0e50065e3433d9a01cc69df19a8f50bf1e8aa1c9..0c5627f8a104e17fb54f55c09da597ef84af5be3 100644 (file)
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -379,14 +379,6 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
        if (sta_prepare_rate_control(local, sta, gfp))
                goto free_txq;
 
-       for (i = 0; i < IEEE80211_NUM_TIDS; i++) {
-               /*
-                * timer_to_tid must be initialized with identity mapping
-                * to enable session_timer's data differentiation. See
-                * sta_rx_agg_session_timer_expired for usage.
-                */
-               sta->timer_to_tid[i] = i;
-       }
        for (i = 0; i < IEEE80211_NUM_ACS; i++) {
                skb_queue_head_init(&sta->ps_tx_buf[i]);
                skb_queue_head_init(&sta->tx_filtered[i]);

diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h
index 5c54acd10562a66df8aa093b9352d097cadb17b9..cd53619435b641c446ed4e0e69eda1d97714f54a 100644 (file)
--- a/net/mac80211/sta_info.h
+++ b/net/mac80211/sta_info.h
@@ -126,6 +126,8 @@ enum ieee80211_agg_stop_reason {
        AGG_STOP_DESTROY_STA,
 };
 
+struct sta_info;
+
 /**
  * struct tid_ampdu_tx - TID aggregation information (Tx).
  *
@@ -133,8 +135,10 @@ enum ieee80211_agg_stop_reason {
  * @session_timer: check if we keep Tx-ing on the TID (by timeout value)
  * @addba_resp_timer: timer for peer's response to addba request
  * @pending: pending frames queue -- use sta's spinlock to protect
+ * @sta: station we are attached to
  * @dialog_token: dialog token for aggregation session
  * @timeout: session timeout value to be filled in ADDBA requests
+ * @tid: TID number
  * @state: session state (see above)
  * @last_tx: jiffies of last tx activity
  * @stop_initiator: initiator of a session stop
@@ -158,6 +162,7 @@ struct tid_ampdu_tx {
        struct timer_list session_timer;
        struct timer_list addba_resp_timer;
        struct sk_buff_head pending;
+       struct sta_info *sta;
        unsigned long state;
        unsigned long last_tx;
        u16 timeout;
@@ -169,6 +174,7 @@ struct tid_ampdu_tx {
        u16 failed_bar_ssn;
        bool bar_pending;
        bool amsdu;
+       u8 tid;
 };
 
 /**
@@ -181,12 +187,14 @@ struct tid_ampdu_tx {
  * @reorder_time: jiffies when skb was added
  * @session_timer: check if peer keeps Tx-ing on the TID (by timeout value)
  * @reorder_timer: releases expired frames from the reorder buffer.
+ * @sta: station we are attached to
  * @last_rx: jiffies of last rx activity
  * @head_seq_num: head sequence number in reordering buffer.
  * @stored_mpdu_num: number of MPDUs in reordering buffer
  * @ssn: Starting Sequence Number expected to be aggregated.
  * @buf_size: buffer size for incoming A-MPDUs
  * @timeout: reset timer value (in TUs).
+ * @tid: TID number
  * @rcu_head: RCU head used for freeing this struct
  * @reorder_lock: serializes access to reorder buffer, see below.
  * @auto_seq: used for offloaded BA sessions to automatically pick head_seq_and
@@ -208,6 +216,7 @@ struct tid_ampdu_rx {
        u64 reorder_buf_filtered;
        struct sk_buff_head *reorder_buf;
        unsigned long *reorder_time;
+       struct sta_info *sta;
        struct timer_list session_timer;
        struct timer_list reorder_timer;
        unsigned long last_rx;
@@ -216,6 +225,7 @@ struct tid_ampdu_rx {
        u16 ssn;
        u16 buf_size;
        u16 timeout;
+       u8 tid;
        u8 auto_seq:1,
           removed:1,
           started:1;
@@ -447,7 +457,6 @@ struct ieee80211_sta_rx_stats {
  *     plus one for non-QoS frames)
  * @tid_seq: per-TID sequence numbers for sending to this STA
  * @ampdu_mlme: A-MPDU state machine state
- * @timer_to_tid: identity mapping to ID timers
  * @mesh: mesh STA information
  * @debugfs_dir: debug filesystem directory dentry
  * @dead: set to true when sta is unlinked
@@ -554,7 +563,6 @@ struct sta_info {
         * Aggregation information, locked with lock.
         */
        struct sta_ampdu_mlme ampdu_mlme;
-       u8 timer_to_tid[IEEE80211_NUM_TIDS];
 
 #ifdef CONFIG_MAC80211_DEBUGFS
        struct dentry *debugfs_dir;