net/mac802154/util.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  *
   4  * Authors:
   5  * Alexander Aring <aar@pengutronix.de>
   6  *
   7  * Based on: net/mac80211/util.c
   8  */
   9
  10 #include "ieee802154_i.h"
  11 #include "driver-ops.h"
  12
  13 /* privid for wpan_phys to determine whether they belong to us or not */
  14 const void *const mac802154_wpan_phy_privid = &mac802154_wpan_phy_privid;
  15
  16 /**
  17  * ieee802154_wake_queue - wake ieee802154 queue
  18  * @hw: main hardware object
  19  *
  20  * Tranceivers usually have either one transmit framebuffer or one framebuffer
  21  * for both transmitting and receiving. Hence, the core currently only handles
  22  * one frame at a time for each phy, which means we had to stop the queue to
  23  * avoid new skb to come during the transmission. The queue then needs to be
  24  * woken up after the operation.
  25  */
  26 static void ieee802154_wake_queue(struct ieee802154_hw *hw)
  27 {
  28         struct ieee802154_local *local = hw_to_local(hw);
  29         struct ieee802154_sub_if_data *sdata;
  30
  31         rcu_read_lock();
  32         clear_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);
  33         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  34                 if (!sdata->dev)
  35                         continue;
  36
  37                 netif_wake_queue(sdata->dev);
  38         }
  39         rcu_read_unlock();
  40 }
  41
  42 /**
  43  * ieee802154_stop_queue - stop ieee802154 queue
  44  * @hw: main hardware object
  45  *
  46  * Tranceivers usually have either one transmit framebuffer or one framebuffer
  47  * for both transmitting and receiving. Hence, the core currently only handles
  48  * one frame at a time for each phy, which means we need to tell upper layers to
  49  * stop giving us new skbs while we are busy with the transmitted one. The queue
  50  * must then be stopped before transmitting.
  51  */
  52 static void ieee802154_stop_queue(struct ieee802154_hw *hw)
  53 {
  54         struct ieee802154_local *local = hw_to_local(hw);
  55         struct ieee802154_sub_if_data *sdata;
  56
  57         rcu_read_lock();
  58         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  59                 if (!sdata->dev)
  60                         continue;
  61
  62                 netif_stop_queue(sdata->dev);
  63         }
  64         rcu_read_unlock();
  65 }
  66
  67 void ieee802154_hold_queue(struct ieee802154_local *local)
  68 {
  69         unsigned long flags;
  70
  71         spin_lock_irqsave(&local->phy->queue_lock, flags);
  72         if (!atomic_fetch_inc(&local->phy->hold_txs))
  73                 ieee802154_stop_queue(&local->hw);
  74         spin_unlock_irqrestore(&local->phy->queue_lock, flags);
  75 }
  76
  77 void ieee802154_release_queue(struct ieee802154_local *local)
  78 {
  79         unsigned long flags;
  80
  81         spin_lock_irqsave(&local->phy->queue_lock, flags);
  82         if (atomic_dec_and_test(&local->phy->hold_txs))
  83                 ieee802154_wake_queue(&local->hw);
  84         spin_unlock_irqrestore(&local->phy->queue_lock, flags);
  85 }
  86
  87 void ieee802154_disable_queue(struct ieee802154_local *local)
  88 {
  89         struct ieee802154_sub_if_data *sdata;
  90
  91         rcu_read_lock();
  92         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
  93                 if (!sdata->dev)
  94                         continue;
  95
  96                 netif_tx_disable(sdata->dev);
  97         }
  98         rcu_read_unlock();
  99 }
 100
 101 enum hrtimer_restart ieee802154_xmit_ifs_timer(struct hrtimer *timer)
 102 {
 103         struct ieee802154_local *local =
 104                 container_of(timer, struct ieee802154_local, ifs_timer);
 105
 106         ieee802154_release_queue(local);
 107
 108         return HRTIMER_NORESTART;
 109 }
 110
 111 void ieee802154_xmit_complete(struct ieee802154_hw *hw, struct sk_buff *skb,
 112                               bool ifs_handling)
 113 {
 114         struct ieee802154_local *local = hw_to_local(hw);
 115
 116         local->tx_result = IEEE802154_SUCCESS;
 117
 118         if (ifs_handling) {
 119                 u8 max_sifs_size;
 120
 121                 /* If transceiver sets CRC on his own we need to use lifs
 122                  * threshold len above 16 otherwise 18, because it's not
 123                  * part of skb->len.
 124                  */
 125                 if (hw->flags & IEEE802154_HW_TX_OMIT_CKSUM)
 126                         max_sifs_size = IEEE802154_MAX_SIFS_FRAME_SIZE -
 127                                         IEEE802154_FCS_LEN;
 128                 else
 129                         max_sifs_size = IEEE802154_MAX_SIFS_FRAME_SIZE;
 130
 131                 if (skb->len > max_sifs_size)
 132                         hrtimer_start(&local->ifs_timer,
 133                                       hw->phy->lifs_period * NSEC_PER_USEC,
 134                                       HRTIMER_MODE_REL);
 135                 else
 136                         hrtimer_start(&local->ifs_timer,
 137                                       hw->phy->sifs_period * NSEC_PER_USEC,
 138                                       HRTIMER_MODE_REL);
 139         } else {
 140                 ieee802154_release_queue(local);
 141         }
 142
 143         dev_consume_skb_any(skb);
 144         if (atomic_dec_and_test(&hw->phy->ongoing_txs))
 145                 wake_up(&hw->phy->sync_txq);
 146 }
 147 EXPORT_SYMBOL(ieee802154_xmit_complete);
 148
 149 void ieee802154_xmit_error(struct ieee802154_hw *hw, struct sk_buff *skb,
 150                            int reason)
 151 {
 152         struct ieee802154_local *local = hw_to_local(hw);
 153
 154         local->tx_result = reason;
 155         ieee802154_release_queue(local);
 156         dev_kfree_skb_any(skb);
 157         if (atomic_dec_and_test(&hw->phy->ongoing_txs))
 158                 wake_up(&hw->phy->sync_txq);
 159 }
 160 EXPORT_SYMBOL(ieee802154_xmit_error);
 161
 162 void ieee802154_xmit_hw_error(struct ieee802154_hw *hw, struct sk_buff *skb)
 163 {
 164         ieee802154_xmit_error(hw, skb, IEEE802154_SYSTEM_ERROR);
 165 }
 166 EXPORT_SYMBOL(ieee802154_xmit_hw_error);
 167
 168 void ieee802154_stop_device(struct ieee802154_local *local)
 169 {
 170         flush_workqueue(local->workqueue);
 171         hrtimer_cancel(&local->ifs_timer);
 172         drv_stop(local);
 173 }