1 /* 2 * Copyright (C) ST-Ericsson AB 2010 3 * Authors: Sjur Brendeland/sjur.brandeland@stericsson.com 4 * Daniel Martensson / Daniel.Martensson@stericsson.com 5 * License terms: GNU General Public License (GPL) version 2 6 */ 7 8 #include <linux/version.h> 9 #include <linux/fs.h> 10 #include <linux/init.h> 11 #include <linux/module.h> 12 #include <linux/netdevice.h> 13 #include <linux/if_ether.h> 14 #include <linux/moduleparam.h> 15 #include <linux/ip.h> 16 #include <linux/sched.h> 17 #include <linux/sockios.h> 18 #include <linux/caif/if_caif.h> 19 #include <net/rtnetlink.h> 20 #include <net/caif/caif_layer.h> 21 #include <net/caif/cfcnfg.h> 22 #include <net/caif/cfpkt.h> 23 #include <net/caif/caif_dev.h> 24 25 /* GPRS PDP connection has MTU to 1500 */ 26 #define SIZE_MTU 1500 27 /* 5 sec. connect timeout */ 28 #define CONNECT_TIMEOUT (5 * HZ) 29 #define CAIF_NET_DEFAULT_QUEUE_LEN 500 30 31 #undef pr_debug 32 #define pr_debug pr_warning 33 34 /*This list is protected by the rtnl lock. */ 35 static LIST_HEAD(chnl_net_list); 36 37 MODULE_LICENSE("GPL"); 38 MODULE_ALIAS_RTNL_LINK("caif"); 39 40 enum caif_states { 41 CAIF_CONNECTED = 1, 42 CAIF_CONNECTING, 43 CAIF_DISCONNECTED, 44 CAIF_SHUTDOWN 45 }; 46 47 struct chnl_net { 48 struct cflayer chnl; 49 struct net_device_stats stats; 50 struct caif_connect_request conn_req; 51 struct list_head list_field; 52 struct net_device *netdev; 53 char name[256]; 54 wait_queue_head_t netmgmt_wq; 55 /* Flow status to remember and control the transmission. */ 56 bool flowenabled; 57 enum caif_states state; 58 }; 59 60 static void robust_list_del(struct list_head *delete_node) 61 { 62 struct list_head *list_node; 63 struct list_head *n; 64 ASSERT_RTNL(); 65 list_for_each_safe(list_node, n, &chnl_net_list) { 66 if (list_node == delete_node) { 67 list_del(list_node); 68 return; 69 } 70 } 71 WARN_ON(1); 72 } 73 74 static int chnl_recv_cb(struct cflayer *layr, struct cfpkt *pkt) 75 { 76 struct sk_buff *skb; 77 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl); 78 int pktlen; 79 int err = 0; 80 81 priv = container_of(layr, struct chnl_net, chnl); 82 83 if (!priv) 84 return -EINVAL; 85 86 /* Get length of CAIF packet. */ 87 pktlen = cfpkt_getlen(pkt); 88 89 skb = (struct sk_buff *) cfpkt_tonative(pkt); 90 /* Pass some minimum information and 91 * send the packet to the net stack. 92 */ 93 skb->dev = priv->netdev; 94 skb->protocol = htons(ETH_P_IP); 95 96 /* If we change the header in loop mode, the checksum is corrupted. */ 97 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP) 98 skb->ip_summed = CHECKSUM_UNNECESSARY; 99 else 100 skb->ip_summed = CHECKSUM_NONE; 101 102 if (in_interrupt()) 103 netif_rx(skb); 104 else 105 netif_rx_ni(skb); 106 107 /* Update statistics. */ 108 priv->netdev->stats.rx_packets++; 109 priv->netdev->stats.rx_bytes += pktlen; 110 111 return err; 112 } 113 114 static int delete_device(struct chnl_net *dev) 115 { 116 ASSERT_RTNL(); 117 if (dev->netdev) 118 unregister_netdevice(dev->netdev); 119 return 0; 120 } 121 122 static void close_work(struct work_struct *work) 123 { 124 struct chnl_net *dev = NULL; 125 struct list_head *list_node; 126 struct list_head *_tmp; 127 /* May be called with or without RTNL lock held */ 128 int islocked = rtnl_is_locked(); 129 if (!islocked) 130 rtnl_lock(); 131 list_for_each_safe(list_node, _tmp, &chnl_net_list) { 132 dev = list_entry(list_node, struct chnl_net, list_field); 133 if (dev->state == CAIF_SHUTDOWN) 134 dev_close(dev->netdev); 135 } 136 if (!islocked) 137 rtnl_unlock(); 138 } 139 static DECLARE_WORK(close_worker, close_work); 140 141 static void chnl_flowctrl_cb(struct cflayer *layr, enum caif_ctrlcmd flow, 142 int phyid) 143 { 144 struct chnl_net *priv = container_of(layr, struct chnl_net, chnl); 145 pr_debug("CAIF: %s(): NET flowctrl func called flow: %s\n", 146 __func__, 147 flow == CAIF_CTRLCMD_FLOW_ON_IND ? "ON" : 148 flow == CAIF_CTRLCMD_INIT_RSP ? "INIT" : 149 flow == CAIF_CTRLCMD_FLOW_OFF_IND ? "OFF" : 150 flow == CAIF_CTRLCMD_DEINIT_RSP ? "CLOSE/DEINIT" : 151 flow == CAIF_CTRLCMD_INIT_FAIL_RSP ? "OPEN_FAIL" : 152 flow == CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND ? 153 "REMOTE_SHUTDOWN" : "UKNOWN CTRL COMMAND"); 154 155 156 157 switch (flow) { 158 case CAIF_CTRLCMD_FLOW_OFF_IND: 159 priv->flowenabled = false; 160 netif_stop_queue(priv->netdev); 161 break; 162 case CAIF_CTRLCMD_DEINIT_RSP: 163 priv->state = CAIF_DISCONNECTED; 164 break; 165 case CAIF_CTRLCMD_INIT_FAIL_RSP: 166 priv->state = CAIF_DISCONNECTED; 167 wake_up_interruptible(&priv->netmgmt_wq); 168 break; 169 case CAIF_CTRLCMD_REMOTE_SHUTDOWN_IND: 170 priv->state = CAIF_SHUTDOWN; 171 netif_tx_disable(priv->netdev); 172 schedule_work(&close_worker); 173 break; 174 case CAIF_CTRLCMD_FLOW_ON_IND: 175 priv->flowenabled = true; 176 netif_wake_queue(priv->netdev); 177 break; 178 case CAIF_CTRLCMD_INIT_RSP: 179 priv->state = CAIF_CONNECTED; 180 priv->flowenabled = true; 181 netif_wake_queue(priv->netdev); 182 wake_up_interruptible(&priv->netmgmt_wq); 183 break; 184 default: 185 break; 186 } 187 } 188 189 static int chnl_net_start_xmit(struct sk_buff *skb, struct net_device *dev) 190 { 191 struct chnl_net *priv; 192 struct cfpkt *pkt = NULL; 193 int len; 194 int result = -1; 195 /* Get our private data. */ 196 priv = netdev_priv(dev); 197 198 if (skb->len > priv->netdev->mtu) { 199 pr_warning("CAIF: %s(): Size of skb exceeded MTU\n", __func__); 200 return -ENOSPC; 201 } 202 203 if (!priv->flowenabled) { 204 pr_debug("CAIF: %s(): dropping packets flow off\n", __func__); 205 return NETDEV_TX_BUSY; 206 } 207 208 if (priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP) 209 swap(ip_hdr(skb)->saddr, ip_hdr(skb)->daddr); 210 211 /* Store original SKB length. */ 212 len = skb->len; 213 214 pkt = cfpkt_fromnative(CAIF_DIR_OUT, (void *) skb); 215 216 /* Send the packet down the stack. */ 217 result = priv->chnl.dn->transmit(priv->chnl.dn, pkt); 218 if (result) { 219 if (result == -EAGAIN) 220 result = NETDEV_TX_BUSY; 221 return result; 222 } 223 224 /* Update statistics. */ 225 dev->stats.tx_packets++; 226 dev->stats.tx_bytes += len; 227 228 return NETDEV_TX_OK; 229 } 230 231 static int chnl_net_open(struct net_device *dev) 232 { 233 struct chnl_net *priv = NULL; 234 int result = -1; 235 ASSERT_RTNL(); 236 priv = netdev_priv(dev); 237 if (!priv) { 238 pr_debug("CAIF: %s(): chnl_net_open: no priv\n", __func__); 239 return -ENODEV; 240 } 241 242 if (priv->state != CAIF_CONNECTING) { 243 priv->state = CAIF_CONNECTING; 244 result = caif_connect_client(&priv->conn_req, &priv->chnl); 245 if (result != 0) { 246 priv->state = CAIF_DISCONNECTED; 247 pr_debug("CAIF: %s(): err: " 248 "Unable to register and open device," 249 " Err:%d\n", 250 __func__, 251 result); 252 return result; 253 } 254 } 255 256 result = wait_event_interruptible_timeout(priv->netmgmt_wq, 257 priv->state != CAIF_CONNECTING, 258 CONNECT_TIMEOUT); 259 260 if (result == -ERESTARTSYS) { 261 pr_debug("CAIF: %s(): wait_event_interruptible" 262 " woken by a signal\n", __func__); 263 return -ERESTARTSYS; 264 } 265 if (result == 0) { 266 pr_debug("CAIF: %s(): connect timeout\n", __func__); 267 caif_disconnect_client(&priv->chnl); 268 priv->state = CAIF_DISCONNECTED; 269 pr_debug("CAIF: %s(): state disconnected\n", __func__); 270 return -ETIMEDOUT; 271 } 272 273 if (priv->state != CAIF_CONNECTED) { 274 pr_debug("CAIF: %s(): connect failed\n", __func__); 275 return -ECONNREFUSED; 276 } 277 pr_debug("CAIF: %s(): CAIF Netdevice connected\n", __func__); 278 return 0; 279 } 280 281 static int chnl_net_stop(struct net_device *dev) 282 { 283 struct chnl_net *priv; 284 285 ASSERT_RTNL(); 286 priv = netdev_priv(dev); 287 priv->state = CAIF_DISCONNECTED; 288 caif_disconnect_client(&priv->chnl); 289 return 0; 290 } 291 292 static int chnl_net_init(struct net_device *dev) 293 { 294 struct chnl_net *priv; 295 ASSERT_RTNL(); 296 priv = netdev_priv(dev); 297 strncpy(priv->name, dev->name, sizeof(priv->name)); 298 return 0; 299 } 300 301 static void chnl_net_uninit(struct net_device *dev) 302 { 303 struct chnl_net *priv; 304 ASSERT_RTNL(); 305 priv = netdev_priv(dev); 306 robust_list_del(&priv->list_field); 307 } 308 309 static const struct net_device_ops netdev_ops = { 310 .ndo_open = chnl_net_open, 311 .ndo_stop = chnl_net_stop, 312 .ndo_init = chnl_net_init, 313 .ndo_uninit = chnl_net_uninit, 314 .ndo_start_xmit = chnl_net_start_xmit, 315 }; 316 317 static void ipcaif_net_setup(struct net_device *dev) 318 { 319 struct chnl_net *priv; 320 dev->netdev_ops = &netdev_ops; 321 dev->destructor = free_netdev; 322 dev->flags |= IFF_NOARP; 323 dev->flags |= IFF_POINTOPOINT; 324 dev->needed_headroom = CAIF_NEEDED_HEADROOM; 325 dev->needed_tailroom = CAIF_NEEDED_TAILROOM; 326 dev->mtu = SIZE_MTU; 327 dev->tx_queue_len = CAIF_NET_DEFAULT_QUEUE_LEN; 328 329 priv = netdev_priv(dev); 330 priv->chnl.receive = chnl_recv_cb; 331 priv->chnl.ctrlcmd = chnl_flowctrl_cb; 332 priv->netdev = dev; 333 priv->conn_req.protocol = CAIFPROTO_DATAGRAM; 334 priv->conn_req.link_selector = CAIF_LINK_HIGH_BANDW; 335 priv->conn_req.priority = CAIF_PRIO_LOW; 336 /* Insert illegal value */ 337 priv->conn_req.sockaddr.u.dgm.connection_id = -1; 338 priv->flowenabled = false; 339 340 ASSERT_RTNL(); 341 init_waitqueue_head(&priv->netmgmt_wq); 342 list_add(&priv->list_field, &chnl_net_list); 343 } 344 345 346 static int ipcaif_fill_info(struct sk_buff *skb, const struct net_device *dev) 347 { 348 struct chnl_net *priv; 349 u8 loop; 350 priv = netdev_priv(dev); 351 NLA_PUT_U32(skb, IFLA_CAIF_IPV4_CONNID, 352 priv->conn_req.sockaddr.u.dgm.connection_id); 353 NLA_PUT_U32(skb, IFLA_CAIF_IPV6_CONNID, 354 priv->conn_req.sockaddr.u.dgm.connection_id); 355 loop = priv->conn_req.protocol == CAIFPROTO_DATAGRAM_LOOP; 356 NLA_PUT_U8(skb, IFLA_CAIF_LOOPBACK, loop); 357 358 359 return 0; 360 nla_put_failure: 361 return -EMSGSIZE; 362 363 } 364 365 static void caif_netlink_parms(struct nlattr *data[], 366 struct caif_connect_request *conn_req) 367 { 368 if (!data) { 369 pr_warning("CAIF: %s: no params data found\n", __func__); 370 return; 371 } 372 if (data[IFLA_CAIF_IPV4_CONNID]) 373 conn_req->sockaddr.u.dgm.connection_id = 374 nla_get_u32(data[IFLA_CAIF_IPV4_CONNID]); 375 if (data[IFLA_CAIF_IPV6_CONNID]) 376 conn_req->sockaddr.u.dgm.connection_id = 377 nla_get_u32(data[IFLA_CAIF_IPV6_CONNID]); 378 if (data[IFLA_CAIF_LOOPBACK]) { 379 if (nla_get_u8(data[IFLA_CAIF_LOOPBACK])) 380 conn_req->protocol = CAIFPROTO_DATAGRAM_LOOP; 381 else 382 conn_req->protocol = CAIFPROTO_DATAGRAM; 383 } 384 } 385 386 static int ipcaif_newlink(struct net *src_net, struct net_device *dev, 387 struct nlattr *tb[], struct nlattr *data[]) 388 { 389 int ret; 390 struct chnl_net *caifdev; 391 ASSERT_RTNL(); 392 caifdev = netdev_priv(dev); 393 caif_netlink_parms(data, &caifdev->conn_req); 394 dev_net_set(caifdev->netdev, src_net); 395 396 ret = register_netdevice(dev); 397 if (ret) 398 pr_warning("CAIF: %s(): device rtml registration failed\n", 399 __func__); 400 return ret; 401 } 402 403 static int ipcaif_changelink(struct net_device *dev, struct nlattr *tb[], 404 struct nlattr *data[]) 405 { 406 struct chnl_net *caifdev; 407 ASSERT_RTNL(); 408 caifdev = netdev_priv(dev); 409 caif_netlink_parms(data, &caifdev->conn_req); 410 netdev_state_change(dev); 411 return 0; 412 } 413 414 static size_t ipcaif_get_size(const struct net_device *dev) 415 { 416 return 417 /* IFLA_CAIF_IPV4_CONNID */ 418 nla_total_size(4) + 419 /* IFLA_CAIF_IPV6_CONNID */ 420 nla_total_size(4) + 421 /* IFLA_CAIF_LOOPBACK */ 422 nla_total_size(2) + 423 0; 424 } 425 426 static const struct nla_policy ipcaif_policy[IFLA_CAIF_MAX + 1] = { 427 [IFLA_CAIF_IPV4_CONNID] = { .type = NLA_U32 }, 428 [IFLA_CAIF_IPV6_CONNID] = { .type = NLA_U32 }, 429 [IFLA_CAIF_LOOPBACK] = { .type = NLA_U8 } 430 }; 431 432 433 static struct rtnl_link_ops ipcaif_link_ops __read_mostly = { 434 .kind = "caif", 435 .priv_size = sizeof(struct chnl_net), 436 .setup = ipcaif_net_setup, 437 .maxtype = IFLA_CAIF_MAX, 438 .policy = ipcaif_policy, 439 .newlink = ipcaif_newlink, 440 .changelink = ipcaif_changelink, 441 .get_size = ipcaif_get_size, 442 .fill_info = ipcaif_fill_info, 443 444 }; 445 446 static int __init chnl_init_module(void) 447 { 448 return rtnl_link_register(&ipcaif_link_ops); 449 } 450 451 static void __exit chnl_exit_module(void) 452 { 453 struct chnl_net *dev = NULL; 454 struct list_head *list_node; 455 struct list_head *_tmp; 456 rtnl_link_unregister(&ipcaif_link_ops); 457 rtnl_lock(); 458 list_for_each_safe(list_node, _tmp, &chnl_net_list) { 459 dev = list_entry(list_node, struct chnl_net, list_field); 460 list_del(list_node); 461 delete_device(dev); 462 } 463 rtnl_unlock(); 464 } 465 466 module_init(chnl_init_module); 467 module_exit(chnl_exit_module); 468