net/mac802154/tx.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright 2007-2012 Siemens AG
   4  *
   5  * Written by:
   6  * Dmitry Eremin-Solenikov <[email protected]>
   7  * Sergey Lapin <[email protected]>
   8  * Maxim Gorbachyov <[email protected]>
   9  * Alexander Smirnov <[email protected]>
  10  */
  11
  12 #include <linux/netdevice.h>
  13 #include <linux/if_arp.h>
  14 #include <linux/crc-ccitt.h>
  15 #include <asm/unaligned.h>
  16
  17 #include <net/rtnetlink.h>
  18 #include <net/ieee802154_netdev.h>
  19 #include <net/mac802154.h>
  20 #include <net/cfg802154.h>
  21
  22 #include "ieee802154_i.h"
  23 #include "driver-ops.h"
  24
  25 void ieee802154_xmit_sync_worker(struct work_struct *work)
  26 {
  27         struct ieee802154_local *local =
  28                 container_of(work, struct ieee802154_local, sync_tx_work);
  29         struct sk_buff *skb = local->tx_skb;
  30         struct net_device *dev = skb->dev;
  31         int res;
  32
  33         res = drv_xmit_sync(local, skb);
  34         if (res)
  35                 goto err_tx;
  36
  37         dev->stats.tx_packets++;
  38         dev->stats.tx_bytes += skb->len;
  39
  40         ieee802154_xmit_complete(&local->hw, skb, false);
  41
  42         return;
  43
  44 err_tx:
  45         /* Restart the netif queue on each sub_if_data object. */
  46         ieee802154_release_queue(local);
  47         if (atomic_dec_and_test(&local->phy->ongoing_txs))
  48                 wake_up(&local->phy->sync_txq);
  49         kfree_skb(skb);
  50         netdev_dbg(dev, "transmission failed\n");
  51 }
  52
  53 static netdev_tx_t
  54 ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb)
  55 {
  56         struct net_device *dev = skb->dev;
  57         int ret;
  58
  59         if (!(local->hw.flags & IEEE802154_HW_TX_OMIT_CKSUM)) {
  60                 struct sk_buff *nskb;
  61                 u16 crc;
  62
  63                 if (unlikely(skb_tailroom(skb) < IEEE802154_FCS_LEN)) {
  64                         nskb = skb_copy_expand(skb, 0, IEEE802154_FCS_LEN,
  65                                                GFP_ATOMIC);
  66                         if (likely(nskb)) {
  67                                 consume_skb(skb);
  68                                 skb = nskb;
  69                         } else {
  70                                 goto err_free_skb;
  71                         }
  72                 }
  73
  74                 crc = crc_ccitt(0, skb->data, skb->len);
  75                 put_unaligned_le16(crc, skb_put(skb, 2));
  76         }
  77
  78         /* Stop the netif queue on each sub_if_data object. */
  79         ieee802154_hold_queue(local);
  80         atomic_inc(&local->phy->ongoing_txs);
  81
  82         /* Drivers should preferably implement the async callback. In some rare
  83          * cases they only provide a sync callback which we will use as a
  84          * fallback.
  85          */
  86         if (local->ops->xmit_async) {
  87                 unsigned int len = skb->len;
  88
  89                 ret = drv_xmit_async(local, skb);
  90                 if (ret)
  91                         goto err_wake_netif_queue;
  92
  93                 dev->stats.tx_packets++;
  94                 dev->stats.tx_bytes += len;
  95         } else {
  96                 local->tx_skb = skb;
  97                 queue_work(local->workqueue, &local->sync_tx_work);
  98         }
  99
 100         return NETDEV_TX_OK;
 101
 102 err_wake_netif_queue:
 103         ieee802154_release_queue(local);
 104         if (atomic_dec_and_test(&local->phy->ongoing_txs))
 105                 wake_up(&local->phy->sync_txq);
 106 err_free_skb:
 107         kfree_skb(skb);
 108         return NETDEV_TX_OK;
 109 }
 110
 111 static int ieee802154_sync_queue(struct ieee802154_local *local)
 112 {
 113         int ret;
 114
 115         ieee802154_hold_queue(local);
 116         ieee802154_disable_queue(local);
 117         wait_event(local->phy->sync_txq, !atomic_read(&local->phy->ongoing_txs));
 118         ret = local->tx_result;
 119         ieee802154_release_queue(local);
 120
 121         return ret;
 122 }
 123
 124 int ieee802154_sync_and_hold_queue(struct ieee802154_local *local)
 125 {
 126         int ret;
 127
 128         ieee802154_hold_queue(local);
 129         ret = ieee802154_sync_queue(local);
 130         set_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);
 131
 132         return ret;
 133 }
 134
 135 int ieee802154_mlme_op_pre(struct ieee802154_local *local)
 136 {
 137         return ieee802154_sync_and_hold_queue(local);
 138 }
 139
 140 int ieee802154_mlme_tx(struct ieee802154_local *local,
 141                        struct ieee802154_sub_if_data *sdata,
 142                        struct sk_buff *skb)
 143 {
 144         int ret;
 145
 146         /* Avoid possible calls to ->ndo_stop() when we asynchronously perform
 147          * MLME transmissions.
 148          */
 149         rtnl_lock();
 150
 151         /* Ensure the device was not stopped, otherwise error out */
 152         if (!local->open_count) {
 153                 rtnl_unlock();
 154                 return -ENETDOWN;
 155         }
 156
 157         /* Warn if the ieee802154 core thinks MLME frames can be sent while the
 158          * net interface expects this cannot happen.
 159          */
 160         if (WARN_ON_ONCE(!netif_running(sdata->dev))) {
 161                 rtnl_unlock();
 162                 return -ENETDOWN;
 163         }
 164
 165         ieee802154_tx(local, skb);
 166         ret = ieee802154_sync_queue(local);
 167
 168         rtnl_unlock();
 169
 170         return ret;
 171 }
 172
 173 void ieee802154_mlme_op_post(struct ieee802154_local *local)
 174 {
 175         ieee802154_release_queue(local);
 176 }
 177
 178 int ieee802154_mlme_tx_one(struct ieee802154_local *local,
 179                            struct ieee802154_sub_if_data *sdata,
 180                            struct sk_buff *skb)
 181 {
 182         int ret;
 183
 184         ieee802154_mlme_op_pre(local);
 185         ret = ieee802154_mlme_tx(local, sdata, skb);
 186         ieee802154_mlme_op_post(local);
 187
 188         return ret;
 189 }
 190
 191 static bool ieee802154_queue_is_stopped(struct ieee802154_local *local)
 192 {
 193         return test_bit(WPAN_PHY_FLAG_STATE_QUEUE_STOPPED, &local->phy->flags);
 194 }
 195
 196 static netdev_tx_t
 197 ieee802154_hot_tx(struct ieee802154_local *local, struct sk_buff *skb)
 198 {
 199         /* Warn if the net interface tries to transmit frames while the
 200          * ieee802154 core assumes the queue is stopped.
 201          */
 202         WARN_ON_ONCE(ieee802154_queue_is_stopped(local));
 203
 204         return ieee802154_tx(local, skb);
 205 }
 206
 207 netdev_tx_t
 208 ieee802154_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev)
 209 {
 210         struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
 211
 212         skb->skb_iif = dev->ifindex;
 213
 214         return ieee802154_hot_tx(sdata->local, skb);
 215 }
 216
 217 netdev_tx_t
 218 ieee802154_subif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 219 {
 220         struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
 221         int rc;
 222
 223         /* TODO we should move it to wpan_dev_hard_header and dev_hard_header
 224          * functions. The reason is wireshark will show a mac header which is
 225          * with security fields but the payload is not encrypted.
 226          */
 227         rc = mac802154_llsec_encrypt(&sdata->sec, skb);
 228         if (rc) {
 229                 netdev_warn(dev, "encryption failed: %i\n", rc);
 230                 kfree_skb(skb);
 231                 return NETDEV_TX_OK;
 232         }
 233
 234         skb->skb_iif = dev->ifindex;
 235
 236         return ieee802154_hot_tx(sdata->local, skb);
 237 }