| 1 | /********************************************************************* |
| 2 | * |
| 3 | * Filename: irlan_eth.c |
| 4 | * Version: |
| 5 | * Description: |
| 6 | * Status: Experimental. |
| 7 | * Author: Dag Brattli <dagb@cs.uit.no> |
| 8 | * Created at: Thu Oct 15 08:37:58 1998 |
| 9 | * Modified at: Tue Mar 21 09:06:41 2000 |
| 10 | * Modified by: Dag Brattli <dagb@cs.uit.no> |
| 11 | * Sources: skeleton.c by Donald Becker <becker@CESDIS.gsfc.nasa.gov> |
| 12 | * slip.c by Laurence Culhane, <loz@holmes.demon.co.uk> |
| 13 | * Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org> |
| 14 | * |
| 15 | * Copyright (c) 1998-2000 Dag Brattli, All Rights Reserved. |
| 16 | * |
| 17 | * This program is free software; you can redistribute it and/or |
| 18 | * modify it under the terms of the GNU General Public License as |
| 19 | * published by the Free Software Foundation; either version 2 of |
| 20 | * the License, or (at your option) any later version. |
| 21 | * |
| 22 | * Neither Dag Brattli nor University of Tromsø admit liability nor |
| 23 | * provide warranty for any of this software. This material is |
| 24 | * provided "AS-IS" and at no charge. |
| 25 | * |
| 26 | ********************************************************************/ |
| 27 | |
| 28 | #include <linux/netdevice.h> |
| 29 | #include <linux/etherdevice.h> |
| 30 | #include <linux/inetdevice.h> |
| 31 | #include <linux/if_arp.h> |
| 32 | #include <linux/module.h> |
| 33 | #include <net/arp.h> |
| 34 | |
| 35 | #include <net/irda/irda.h> |
| 36 | #include <net/irda/irmod.h> |
| 37 | #include <net/irda/irlan_common.h> |
| 38 | #include <net/irda/irlan_client.h> |
| 39 | #include <net/irda/irlan_event.h> |
| 40 | #include <net/irda/irlan_eth.h> |
| 41 | |
| 42 | static int irlan_eth_open(struct net_device *dev); |
| 43 | static int irlan_eth_close(struct net_device *dev); |
| 44 | static int irlan_eth_xmit(struct sk_buff *skb, struct net_device *dev); |
| 45 | static void irlan_eth_set_multicast_list( struct net_device *dev); |
| 46 | static struct net_device_stats *irlan_eth_get_stats(struct net_device *dev); |
| 47 | |
| 48 | /* |
| 49 | * Function irlan_eth_setup (dev) |
| 50 | * |
| 51 | * The network device initialization function. |
| 52 | * |
| 53 | */ |
| 54 | static void irlan_eth_setup(struct net_device *dev) |
| 55 | { |
| 56 | dev->open = irlan_eth_open; |
| 57 | dev->stop = irlan_eth_close; |
| 58 | dev->hard_start_xmit = irlan_eth_xmit; |
| 59 | dev->get_stats = irlan_eth_get_stats; |
| 60 | dev->set_multicast_list = irlan_eth_set_multicast_list; |
| 61 | dev->destructor = free_netdev; |
| 62 | |
| 63 | ether_setup(dev); |
| 64 | |
| 65 | /* |
| 66 | * Lets do all queueing in IrTTP instead of this device driver. |
| 67 | * Queueing here as well can introduce some strange latency |
| 68 | * problems, which we will avoid by setting the queue size to 0. |
| 69 | */ |
| 70 | /* |
| 71 | * The bugs in IrTTP and IrLAN that created this latency issue |
| 72 | * have now been fixed, and we can propagate flow control properly |
| 73 | * to the network layer. However, this requires a minimal queue of |
| 74 | * packets for the device. |
| 75 | * Without flow control, the Tx Queue is 14 (ttp) + 0 (dev) = 14 |
| 76 | * With flow control, the Tx Queue is 7 (ttp) + 4 (dev) = 11 |
| 77 | * See irlan_eth_flow_indication()... |
| 78 | * Note : this number was randomly selected and would need to |
| 79 | * be adjusted. |
| 80 | * Jean II */ |
| 81 | dev->tx_queue_len = 4; |
| 82 | } |
| 83 | |
| 84 | /* |
| 85 | * Function alloc_irlandev |
| 86 | * |
| 87 | * Allocate network device and control block |
| 88 | * |
| 89 | */ |
| 90 | struct net_device *alloc_irlandev(const char *name) |
| 91 | { |
| 92 | return alloc_netdev(sizeof(struct irlan_cb), name, |
| 93 | irlan_eth_setup); |
| 94 | } |
| 95 | |
| 96 | /* |
| 97 | * Function irlan_eth_open (dev) |
| 98 | * |
| 99 | * Network device has been opened by user |
| 100 | * |
| 101 | */ |
| 102 | static int irlan_eth_open(struct net_device *dev) |
| 103 | { |
| 104 | struct irlan_cb *self = netdev_priv(dev); |
| 105 | |
| 106 | IRDA_DEBUG(2, "%s()\n", __func__ ); |
| 107 | |
| 108 | /* Ready to play! */ |
| 109 | netif_stop_queue(dev); /* Wait until data link is ready */ |
| 110 | |
| 111 | /* We are now open, so time to do some work */ |
| 112 | self->disconnect_reason = 0; |
| 113 | irlan_client_wakeup(self, self->saddr, self->daddr); |
| 114 | |
| 115 | /* Make sure we have a hardware address before we return, |
| 116 | so DHCP clients gets happy */ |
| 117 | return wait_event_interruptible(self->open_wait, |
| 118 | !self->tsap_data->connected); |
| 119 | } |
| 120 | |
| 121 | /* |
| 122 | * Function irlan_eth_close (dev) |
| 123 | * |
| 124 | * Stop the ether network device, his function will usually be called by |
| 125 | * ifconfig down. We should now disconnect the link, We start the |
| 126 | * close timer, so that the instance will be removed if we are unable |
| 127 | * to discover the remote device after the disconnect. |
| 128 | */ |
| 129 | static int irlan_eth_close(struct net_device *dev) |
| 130 | { |
| 131 | struct irlan_cb *self = netdev_priv(dev); |
| 132 | |
| 133 | IRDA_DEBUG(2, "%s()\n", __func__ ); |
| 134 | |
| 135 | /* Stop device */ |
| 136 | netif_stop_queue(dev); |
| 137 | |
| 138 | irlan_close_data_channel(self); |
| 139 | irlan_close_tsaps(self); |
| 140 | |
| 141 | irlan_do_client_event(self, IRLAN_LMP_DISCONNECT, NULL); |
| 142 | irlan_do_provider_event(self, IRLAN_LMP_DISCONNECT, NULL); |
| 143 | |
| 144 | /* Remove frames queued on the control channel */ |
| 145 | skb_queue_purge(&self->client.txq); |
| 146 | |
| 147 | self->client.tx_busy = 0; |
| 148 | |
| 149 | return 0; |
| 150 | } |
| 151 | |
| 152 | /* |
| 153 | * Function irlan_eth_tx (skb) |
| 154 | * |
| 155 | * Transmits ethernet frames over IrDA link. |
| 156 | * |
| 157 | */ |
| 158 | static int irlan_eth_xmit(struct sk_buff *skb, struct net_device *dev) |
| 159 | { |
| 160 | struct irlan_cb *self = netdev_priv(dev); |
| 161 | int ret; |
| 162 | |
| 163 | /* skb headroom large enough to contain all IrDA-headers? */ |
| 164 | if ((skb_headroom(skb) < self->max_header_size) || (skb_shared(skb))) { |
| 165 | struct sk_buff *new_skb = |
| 166 | skb_realloc_headroom(skb, self->max_header_size); |
| 167 | |
| 168 | /* We have to free the original skb anyway */ |
| 169 | dev_kfree_skb(skb); |
| 170 | |
| 171 | /* Did the realloc succeed? */ |
| 172 | if (new_skb == NULL) |
| 173 | return 0; |
| 174 | |
| 175 | /* Use the new skb instead */ |
| 176 | skb = new_skb; |
| 177 | } |
| 178 | |
| 179 | dev->trans_start = jiffies; |
| 180 | |
| 181 | /* Now queue the packet in the transport layer */ |
| 182 | if (self->use_udata) |
| 183 | ret = irttp_udata_request(self->tsap_data, skb); |
| 184 | else |
| 185 | ret = irttp_data_request(self->tsap_data, skb); |
| 186 | |
| 187 | if (ret < 0) { |
| 188 | /* |
| 189 | * IrTTPs tx queue is full, so we just have to |
| 190 | * drop the frame! You might think that we should |
| 191 | * just return -1 and don't deallocate the frame, |
| 192 | * but that is dangerous since it's possible that |
| 193 | * we have replaced the original skb with a new |
| 194 | * one with larger headroom, and that would really |
| 195 | * confuse do_dev_queue_xmit() in dev.c! I have |
| 196 | * tried :-) DB |
| 197 | */ |
| 198 | /* irttp_data_request already free the packet */ |
| 199 | self->stats.tx_dropped++; |
| 200 | } else { |
| 201 | self->stats.tx_packets++; |
| 202 | self->stats.tx_bytes += skb->len; |
| 203 | } |
| 204 | |
| 205 | return 0; |
| 206 | } |
| 207 | |
| 208 | /* |
| 209 | * Function irlan_eth_receive (handle, skb) |
| 210 | * |
| 211 | * This function gets the data that is received on the data channel |
| 212 | * |
| 213 | */ |
| 214 | int irlan_eth_receive(void *instance, void *sap, struct sk_buff *skb) |
| 215 | { |
| 216 | struct irlan_cb *self = instance; |
| 217 | |
| 218 | if (skb == NULL) { |
| 219 | ++self->stats.rx_dropped; |
| 220 | return 0; |
| 221 | } |
| 222 | if (skb->len < ETH_HLEN) { |
| 223 | IRDA_DEBUG(0, "%s() : IrLAN frame too short (%d)\n", |
| 224 | __func__, skb->len); |
| 225 | ++self->stats.rx_dropped; |
| 226 | dev_kfree_skb(skb); |
| 227 | return 0; |
| 228 | } |
| 229 | |
| 230 | /* |
| 231 | * Adopt this frame! Important to set all these fields since they |
| 232 | * might have been previously set by the low level IrDA network |
| 233 | * device driver |
| 234 | */ |
| 235 | skb->protocol = eth_type_trans(skb, self->dev); /* Remove eth header */ |
| 236 | |
| 237 | self->stats.rx_packets++; |
| 238 | self->stats.rx_bytes += skb->len; |
| 239 | |
| 240 | netif_rx(skb); /* Eat it! */ |
| 241 | |
| 242 | return 0; |
| 243 | } |
| 244 | |
| 245 | /* |
| 246 | * Function irlan_eth_flow (status) |
| 247 | * |
| 248 | * Do flow control between IP/Ethernet and IrLAN/IrTTP. This is done by |
| 249 | * controlling the queue stop/start. |
| 250 | * |
| 251 | * The IrDA link layer has the advantage to have flow control, and |
| 252 | * IrTTP now properly handles that. Flow controlling the higher layers |
| 253 | * prevent us to drop Tx packets in here (up to 15% for a TCP socket, |
| 254 | * more for UDP socket). |
| 255 | * Also, this allow us to reduce the overall transmit queue, which means |
| 256 | * less latency in case of mixed traffic. |
| 257 | * Jean II |
| 258 | */ |
| 259 | void irlan_eth_flow_indication(void *instance, void *sap, LOCAL_FLOW flow) |
| 260 | { |
| 261 | struct irlan_cb *self; |
| 262 | struct net_device *dev; |
| 263 | |
| 264 | self = (struct irlan_cb *) instance; |
| 265 | |
| 266 | IRDA_ASSERT(self != NULL, return;); |
| 267 | IRDA_ASSERT(self->magic == IRLAN_MAGIC, return;); |
| 268 | |
| 269 | dev = self->dev; |
| 270 | |
| 271 | IRDA_ASSERT(dev != NULL, return;); |
| 272 | |
| 273 | IRDA_DEBUG(0, "%s() : flow %s ; running %d\n", __func__, |
| 274 | flow == FLOW_STOP ? "FLOW_STOP" : "FLOW_START", |
| 275 | netif_running(dev)); |
| 276 | |
| 277 | switch (flow) { |
| 278 | case FLOW_STOP: |
| 279 | /* IrTTP is full, stop higher layers */ |
| 280 | netif_stop_queue(dev); |
| 281 | break; |
| 282 | case FLOW_START: |
| 283 | default: |
| 284 | /* Tell upper layers that its time to transmit frames again */ |
| 285 | /* Schedule network layer */ |
| 286 | netif_wake_queue(dev); |
| 287 | break; |
| 288 | } |
| 289 | } |
| 290 | |
| 291 | /* |
| 292 | * Function irlan_etc_send_gratuitous_arp (dev) |
| 293 | * |
| 294 | * Send gratuitous ARP to announce that we have changed |
| 295 | * hardware address, so that all peers updates their ARP tables |
| 296 | */ |
| 297 | void irlan_eth_send_gratuitous_arp(struct net_device *dev) |
| 298 | { |
| 299 | #ifdef CONFIG_INET |
| 300 | struct in_device *in_dev; |
| 301 | |
| 302 | /* |
| 303 | * When we get a new MAC address do a gratuitous ARP. This |
| 304 | * is useful if we have changed access points on the same |
| 305 | * subnet. |
| 306 | */ |
| 307 | IRDA_DEBUG(4, "IrLAN: Sending gratuitous ARP\n"); |
| 308 | rcu_read_lock(); |
| 309 | in_dev = __in_dev_get_rcu(dev); |
| 310 | if (in_dev == NULL) |
| 311 | goto out; |
| 312 | if (in_dev->ifa_list) |
| 313 | |
| 314 | arp_send(ARPOP_REQUEST, ETH_P_ARP, |
| 315 | in_dev->ifa_list->ifa_address, |
| 316 | dev, |
| 317 | in_dev->ifa_list->ifa_address, |
| 318 | NULL, dev->dev_addr, NULL); |
| 319 | out: |
| 320 | rcu_read_unlock(); |
| 321 | #endif /* CONFIG_INET */ |
| 322 | } |
| 323 | |
| 324 | /* |
| 325 | * Function set_multicast_list (dev) |
| 326 | * |
| 327 | * Configure the filtering of the device |
| 328 | * |
| 329 | */ |
| 330 | #define HW_MAX_ADDRS 4 /* Must query to get it! */ |
| 331 | static void irlan_eth_set_multicast_list(struct net_device *dev) |
| 332 | { |
| 333 | struct irlan_cb *self = netdev_priv(dev); |
| 334 | |
| 335 | IRDA_DEBUG(2, "%s()\n", __func__ ); |
| 336 | |
| 337 | /* Check if data channel has been connected yet */ |
| 338 | if (self->client.state != IRLAN_DATA) { |
| 339 | IRDA_DEBUG(1, "%s(), delaying!\n", __func__ ); |
| 340 | return; |
| 341 | } |
| 342 | |
| 343 | if (dev->flags & IFF_PROMISC) { |
| 344 | /* Enable promiscuous mode */ |
| 345 | IRDA_WARNING("Promiscuous mode not implemented by IrLAN!\n"); |
| 346 | } |
| 347 | else if ((dev->flags & IFF_ALLMULTI) || dev->mc_count > HW_MAX_ADDRS) { |
| 348 | /* Disable promiscuous mode, use normal mode. */ |
| 349 | IRDA_DEBUG(4, "%s(), Setting multicast filter\n", __func__ ); |
| 350 | /* hardware_set_filter(NULL); */ |
| 351 | |
| 352 | irlan_set_multicast_filter(self, TRUE); |
| 353 | } |
| 354 | else if (dev->mc_count) { |
| 355 | IRDA_DEBUG(4, "%s(), Setting multicast filter\n", __func__ ); |
| 356 | /* Walk the address list, and load the filter */ |
| 357 | /* hardware_set_filter(dev->mc_list); */ |
| 358 | |
| 359 | irlan_set_multicast_filter(self, TRUE); |
| 360 | } |
| 361 | else { |
| 362 | IRDA_DEBUG(4, "%s(), Clearing multicast filter\n", __func__ ); |
| 363 | irlan_set_multicast_filter(self, FALSE); |
| 364 | } |
| 365 | |
| 366 | if (dev->flags & IFF_BROADCAST) |
| 367 | irlan_set_broadcast_filter(self, TRUE); |
| 368 | else |
| 369 | irlan_set_broadcast_filter(self, FALSE); |
| 370 | } |
| 371 | |
| 372 | /* |
| 373 | * Function irlan_get_stats (dev) |
| 374 | * |
| 375 | * Get the current statistics for this device |
| 376 | * |
| 377 | */ |
| 378 | static struct net_device_stats *irlan_eth_get_stats(struct net_device *dev) |
| 379 | { |
| 380 | struct irlan_cb *self = netdev_priv(dev); |
| 381 | |
| 382 | return &self->stats; |
| 383 | } |