1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright 2007-2012 Siemens AG 4 * 5 * Written by: 6 * Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> 7 * Sergey Lapin <slapin@ossfans.org> 8 * Maxim Gorbachyov <maxim.gorbachev@siemens.com> 9 * Alexander Smirnov <alex.bluesman.smirnov@gmail.com> 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 } 238