net/mac802154/tx.c

   1 /*
   2  * Copyright 2007-2012 Siemens AG
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2
   6  * as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * Written by:
  14  * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
  15  * Sergey Lapin <slapin@ossfans.org>
  16  * Maxim Gorbachyov <maxim.gorbachev@siemens.com>
  17  * Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
  18  */
  19
  20 #include <linux/netdevice.h>
  21 #include <linux/if_arp.h>
  22 #include <linux/crc-ccitt.h>
  23 #include <asm/unaligned.h>
  24
  25 #include <net/rtnetlink.h>
  26 #include <net/ieee802154_netdev.h>
  27 #include <net/mac802154.h>
  28 #include <net/cfg802154.h>
  29
  30 #include "ieee802154_i.h"
  31 #include "driver-ops.h"
  32
  33 void ieee802154_xmit_worker(struct work_struct *work)
  34 {
  35         struct ieee802154_local *local =
  36                 container_of(work, struct ieee802154_local, tx_work);
  37         struct sk_buff *skb = local->tx_skb;
  38         struct net_device *dev = skb->dev;
  39         int res;
  40
  41         rtnl_lock();
  42
  43         /* check if ifdown occurred while schedule */
  44         if (!netif_running(dev))
  45                 goto err_tx;
  46
  47         res = drv_xmit_sync(local, skb);
  48         if (res)
  49                 goto err_tx;
  50
  51         ieee802154_xmit_complete(&local->hw, skb, false);
  52
  53         dev->stats.tx_packets++;
  54         dev->stats.tx_bytes += skb->len;
  55
  56         rtnl_unlock();
  57
  58         return;
  59
  60 err_tx:
  61         /* Restart the netif queue on each sub_if_data object. */
  62         ieee802154_wake_queue(&local->hw);
  63         rtnl_unlock();
  64         kfree_skb(skb);
  65         netdev_dbg(dev, "transmission failed\n");
  66 }
  67
  68 static netdev_tx_t
  69 ieee802154_tx(struct ieee802154_local *local, struct sk_buff *skb)
  70 {
  71         struct net_device *dev = skb->dev;
  72         int ret;
  73
  74         if (!(local->hw.flags & IEEE802154_HW_TX_OMIT_CKSUM)) {
  75                 u16 crc = crc_ccitt(0, skb->data, skb->len);
  76
  77                 put_unaligned_le16(crc, skb_put(skb, 2));
  78         }
  79
  80         /* Stop the netif queue on each sub_if_data object. */
  81         ieee802154_stop_queue(&local->hw);
  82
  83         /* async is priority, otherwise sync is fallback */
  84         if (local->ops->xmit_async) {
  85                 ret = drv_xmit_async(local, skb);
  86                 if (ret) {
  87                         ieee802154_wake_queue(&local->hw);
  88                         goto err_tx;
  89                 }
  90
  91                 dev->stats.tx_packets++;
  92                 dev->stats.tx_bytes += skb->len;
  93         } else {
  94                 local->tx_skb = skb;
  95                 queue_work(local->workqueue, &local->tx_work);
  96         }
  97
  98         return NETDEV_TX_OK;
  99
 100 err_tx:
 101         kfree_skb(skb);
 102         return NETDEV_TX_OK;
 103 }
 104
 105 netdev_tx_t
 106 ieee802154_monitor_start_xmit(struct sk_buff *skb, struct net_device *dev)
 107 {
 108         struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
 109
 110         skb->skb_iif = dev->ifindex;
 111
 112         return ieee802154_tx(sdata->local, skb);
 113 }
 114
 115 netdev_tx_t
 116 ieee802154_subif_start_xmit(struct sk_buff *skb, struct net_device *dev)
 117 {
 118         struct ieee802154_sub_if_data *sdata = IEEE802154_DEV_TO_SUB_IF(dev);
 119         int rc;
 120
 121         /* TODO we should move it to wpan_dev_hard_header and dev_hard_header
 122          * functions. The reason is wireshark will show a mac header which is
 123          * with security fields but the payload is not encrypted.
 124          */
 125         rc = mac802154_llsec_encrypt(&sdata->sec, skb);
 126         if (rc) {
 127                 netdev_warn(dev, "encryption failed: %i\n", rc);
 128                 kfree_skb(skb);
 129                 return NETDEV_TX_OK;
 130         }
 131
 132         skb->skb_iif = dev->ifindex;
 133
 134         return ieee802154_tx(sdata->local, skb);
 135 }