lwip_tcpip.c

00001 /**
00002  * @file
00003  * Sequential API Main thread module
00004  *
00005  */
00006 
00007 /*
00008  * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
00009  * All rights reserved.
00010  *
00011  * Redistribution and use in source and binary forms, with or without modification,
00012  * are permitted provided that the following conditions are met:
00013  *
00014  * 1. Redistributions of source code must retain the above copyright notice,
00015  *    this list of conditions and the following disclaimer.
00016  * 2. Redistributions in binary form must reproduce the above copyright notice,
00017  *    this list of conditions and the following disclaimer in the documentation
00018  *    and/or other materials provided with the distribution.
00019  * 3. The name of the author may not be used to endorse or promote products
00020  *    derived from this software without specific prior written permission.
00021  *
00022  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
00023  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
00024  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
00025  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00026  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
00027  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00028  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00029  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
00030  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
00031  * OF SUCH DAMAGE.
00032  *
00033  * This file is part of the lwIP TCP/IP stack.
00034  *
00035  * Author: Adam Dunkels <adam@sics.se>
00036  *
00037  */
00038 
00039 #include "lwip/opt.h"
00040 
00041 #if !NO_SYS /* don't build if not configured for use in lwipopts.h */
00042 
00043 #include "lwip/priv/tcpip_priv.h"
00044 #include "lwip/sys.h"
00045 #include "lwip/memp.h"
00046 #include "lwip/mem.h"
00047 #include "lwip/init.h"
00048 #include "lwip/ip.h"
00049 #include "lwip/pbuf.h"
00050 #include "lwip/etharp.h"
00051 #include "netif/lwip_ethernet.h"
00052 
00053 #define TCPIP_MSG_VAR_REF(name)     API_VAR_REF(name)
00054 #define TCPIP_MSG_VAR_DECLARE(name) API_VAR_DECLARE(struct tcpip_msg, name)
00055 #define TCPIP_MSG_VAR_ALLOC(name)   API_VAR_ALLOC(struct tcpip_msg, MEMP_TCPIP_MSG_API, name, ERR_MEM)
00056 #define TCPIP_MSG_VAR_FREE(name)    API_VAR_FREE(MEMP_TCPIP_MSG_API, name)
00057 
00058 /* global variables */
00059 static tcpip_init_done_fn tcpip_init_done;
00060 static void *tcpip_init_done_arg;
00061 static sys_mbox_t mbox;
00062 
00063 #if LWIP_TCPIP_CORE_LOCKING
00064 /** The global semaphore to lock the stack. */
00065 sys_mutex_t lock_tcpip_core;
00066 #endif /* LWIP_TCPIP_CORE_LOCKING */
00067 
00068 #if LWIP_TIMERS
00069 /* wait for a message, timeouts are processed while waiting */
00070 #define TCPIP_MBOX_FETCH(mbox, msg) sys_timeouts_mbox_fetch(mbox, msg)
00071 #else /* LWIP_TIMERS */
00072 /* wait for a message with timers disabled (e.g. pass a timer-check trigger into tcpip_thread) */
00073 #define TCPIP_MBOX_FETCH(mbox, msg) sys_mbox_fetch(mbox, msg)
00074 #endif /* LWIP_TIMERS */
00075 
00076 /**
00077  * The main lwIP thread. This thread has exclusive access to lwIP core functions
00078  * (unless access to them is not locked). Other threads communicate with this
00079  * thread using message boxes.
00080  *
00081  * It also starts all the timers to make sure they are running in the right
00082  * thread context.
00083  *
00084  * @param arg unused argument
00085  */
00086 static void
00087 tcpip_thread(void *arg)
00088 {
00089   struct tcpip_msg *msg;
00090   LWIP_UNUSED_ARG(arg);
00091 
00092   if (tcpip_init_done != NULL) {
00093     tcpip_init_done(tcpip_init_done_arg);
00094   }
00095 
00096   LOCK_TCPIP_CORE();
00097   while (1) {                          /* MAIN Loop */
00098     UNLOCK_TCPIP_CORE();
00099     LWIP_TCPIP_THREAD_ALIVE();
00100     /* wait for a message, timeouts are processed while waiting */
00101     TCPIP_MBOX_FETCH(&mbox, (void **)&msg);
00102     LOCK_TCPIP_CORE();
00103     if (msg == NULL) {
00104       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: invalid message: NULL\n"));
00105       LWIP_ASSERT("tcpip_thread: invalid message", 0);
00106       continue;
00107     }
00108     switch (msg->type) {
00109 #if !LWIP_TCPIP_CORE_LOCKING
00110     case TCPIP_MSG_API:
00111       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: API message %p\n", (void *)msg));
00112       msg->msg.api_msg.function(msg->msg.api_msg.msg);
00113       break;
00114     case TCPIP_MSG_API_CALL:
00115       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: API CALL message %p\n", (void *)msg));
00116       msg->msg.api_call.arg->err = msg->msg.api_call.function(msg->msg.api_call.arg);
00117       sys_sem_signal(msg->msg.api_call.sem);
00118       break;
00119 #endif /* !LWIP_TCPIP_CORE_LOCKING */
00120 
00121 #if !LWIP_TCPIP_CORE_LOCKING_INPUT
00122     case TCPIP_MSG_INPKT:
00123       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: PACKET %p\n", (void *)msg));
00124       msg->msg.inp.input_fn(msg->msg.inp.p, msg->msg.inp.netif);
00125       memp_free(MEMP_TCPIP_MSG_INPKT, msg);
00126       break;
00127 #endif /* !LWIP_TCPIP_CORE_LOCKING_INPUT */
00128 
00129 #if LWIP_TCPIP_TIMEOUT && LWIP_TIMERS
00130     case TCPIP_MSG_TIMEOUT:
00131       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: TIMEOUT %p\n", (void *)msg));
00132       sys_timeout(msg->msg.tmo.msecs, msg->msg.tmo.h, msg->msg.tmo.arg);
00133       memp_free(MEMP_TCPIP_MSG_API, msg);
00134       break;
00135     case TCPIP_MSG_UNTIMEOUT:
00136       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: UNTIMEOUT %p\n", (void *)msg));
00137       sys_untimeout(msg->msg.tmo.h, msg->msg.tmo.arg);
00138       memp_free(MEMP_TCPIP_MSG_API, msg);
00139       break;
00140 #endif /* LWIP_TCPIP_TIMEOUT && LWIP_TIMERS */
00141 
00142     case TCPIP_MSG_CALLBACK:
00143       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: CALLBACK %p\n", (void *)msg));
00144       msg->msg.cb.function(msg->msg.cb.ctx);
00145       memp_free(MEMP_TCPIP_MSG_API, msg);
00146       break;
00147 
00148     case TCPIP_MSG_CALLBACK_STATIC:
00149       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: CALLBACK_STATIC %p\n", (void *)msg));
00150       msg->msg.cb.function(msg->msg.cb.ctx);
00151       break;
00152 
00153     default:
00154       LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_thread: invalid message: %d\n", msg->type));
00155       LWIP_ASSERT("tcpip_thread: invalid message", 0);
00156       break;
00157     }
00158   }
00159 }
00160 
00161 /**
00162  * Pass a received packet to tcpip_thread for input processing
00163  *
00164  * @param p the received packet
00165  * @param inp the network interface on which the packet was received
00166  * @param input_fn input function to call
00167  */
00168 err_t
00169 tcpip_inpkt(struct pbuf *p, struct netif *inp, netif_input_fn input_fn)
00170 {
00171 #if LWIP_TCPIP_CORE_LOCKING_INPUT
00172   err_t ret;
00173   LWIP_DEBUGF(TCPIP_DEBUG, ("tcpip_inpkt: PACKET %p/%p\n", (void *)p, (void *)inp));
00174   LOCK_TCPIP_CORE();
00175   ret = input_fn(p, inp);
00176   UNLOCK_TCPIP_CORE();
00177   return ret;
00178 #else /* LWIP_TCPIP_CORE_LOCKING_INPUT */
00179   struct tcpip_msg *msg;
00180 
00181   LWIP_ASSERT("Invalid mbox", sys_mbox_valid_val(mbox));
00182 
00183   msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_INPKT);
00184   if (msg == NULL) {
00185     return ERR_MEM;
00186   }
00187 
00188   msg->type = TCPIP_MSG_INPKT;
00189   msg->msg.inp.p = p;
00190   msg->msg.inp.netif = inp;
00191   msg->msg.inp.input_fn = input_fn;
00192   if (sys_mbox_trypost(&mbox, msg) != ERR_OK) {
00193     memp_free(MEMP_TCPIP_MSG_INPKT, msg);
00194     return ERR_MEM;
00195   }
00196   return ERR_OK;
00197 #endif /* LWIP_TCPIP_CORE_LOCKING_INPUT */
00198 }
00199 
00200 /**
00201  * @ingroup lwip_os
00202  * Pass a received packet to tcpip_thread for input processing with
00203  * ethernet_input or ip_input. Don't call directly, pass to netif_add()
00204  * and call netif->input().
00205  *
00206  * @param p the received packet, p->payload pointing to the Ethernet header or
00207  *          to an IP header (if inp doesn't have NETIF_FLAG_ETHARP or
00208  *          NETIF_FLAG_ETHERNET flags)
00209  * @param inp the network interface on which the packet was received
00210  */
00211 err_t
00212 tcpip_input(struct pbuf *p, struct netif *inp)
00213 {
00214 #if LWIP_ETHERNET
00215   if (inp->flags & (NETIF_FLAG_ETHARP | NETIF_FLAG_ETHERNET)) {
00216     return tcpip_inpkt(p, inp, ethernet_input);
00217   } else
00218 #endif /* LWIP_ETHERNET */
00219   return tcpip_inpkt(p, inp, ip_input);
00220 }
00221 
00222 /**
00223  * Call a specific function in the thread context of
00224  * tcpip_thread for easy access synchronization.
00225  * A function called in that way may access lwIP core code
00226  * without fearing concurrent access.
00227  *
00228  * @param function the function to call
00229  * @param ctx parameter passed to f
00230  * @param block 1 to block until the request is posted, 0 to non-blocking mode
00231  * @return ERR_OK if the function was called, another err_t if not
00232  */
00233 err_t
00234 tcpip_callback_with_block(tcpip_callback_fn function, void *ctx, u8_t block)
00235 {
00236   struct tcpip_msg *msg;
00237 
00238   LWIP_ASSERT("Invalid mbox", sys_mbox_valid_val(mbox));
00239 
00240   msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
00241   if (msg == NULL) {
00242     return ERR_MEM;
00243   }
00244 
00245   msg->type = TCPIP_MSG_CALLBACK;
00246   msg->msg.cb.function = function;
00247   msg->msg.cb.ctx = ctx;
00248   if (block) {
00249     sys_mbox_post(&mbox, msg);
00250   } else {
00251     if (sys_mbox_trypost(&mbox, msg) != ERR_OK) {
00252       memp_free(MEMP_TCPIP_MSG_API, msg);
00253       return ERR_MEM;
00254     }
00255   }
00256   return ERR_OK;
00257 }
00258 
00259 #if LWIP_TCPIP_TIMEOUT && LWIP_TIMERS
00260 /**
00261  * call sys_timeout in tcpip_thread
00262  *
00263  * @param msecs time in milliseconds for timeout
00264  * @param h function to be called on timeout
00265  * @param arg argument to pass to timeout function h
00266  * @return ERR_MEM on memory error, ERR_OK otherwise
00267  */
00268 err_t
00269 tcpip_timeout(u32_t msecs, sys_timeout_handler h, void *arg)
00270 {
00271   struct tcpip_msg *msg;
00272 
00273   LWIP_ASSERT("Invalid mbox", sys_mbox_valid_val(mbox));
00274 
00275   msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
00276   if (msg == NULL) {
00277     return ERR_MEM;
00278   }
00279 
00280   msg->type = TCPIP_MSG_TIMEOUT;
00281   msg->msg.tmo.msecs = msecs;
00282   msg->msg.tmo.h = h;
00283   msg->msg.tmo.arg = arg;
00284   sys_mbox_post(&mbox, msg);
00285   return ERR_OK;
00286 }
00287 
00288 /**
00289  * call sys_untimeout in tcpip_thread
00290  *
00291  * @param h function to be called on timeout
00292  * @param arg argument to pass to timeout function h
00293  * @return ERR_MEM on memory error, ERR_OK otherwise
00294  */
00295 err_t
00296 tcpip_untimeout(sys_timeout_handler h, void *arg)
00297 {
00298   struct tcpip_msg *msg;
00299 
00300   LWIP_ASSERT("Invalid mbox", sys_mbox_valid_val(mbox));
00301 
00302   msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
00303   if (msg == NULL) {
00304     return ERR_MEM;
00305   }
00306 
00307   msg->type = TCPIP_MSG_UNTIMEOUT;
00308   msg->msg.tmo.h = h;
00309   msg->msg.tmo.arg = arg;
00310   sys_mbox_post(&mbox, msg);
00311   return ERR_OK;
00312 }
00313 #endif /* LWIP_TCPIP_TIMEOUT && LWIP_TIMERS */
00314 
00315 
00316 /**
00317  * Sends a message to TCPIP thread to call a function. Caller thread blocks on
00318  * on a provided semaphore, which ist NOT automatically signalled by TCPIP thread,
00319  * this has to be done by the user.
00320  * It is recommended to use LWIP_TCPIP_CORE_LOCKING since this is the way
00321  * with least runtime overhead.
00322  *
00323  * @param fn function to be called from TCPIP thread
00324  * @param apimsg argument to API function
00325  * @param sem semaphore to wait on
00326  * @return ERR_OK if the function was called, another err_t if not
00327  */
00328 err_t
00329 tcpip_send_msg_wait_sem(tcpip_callback_fn fn, void *apimsg, sys_sem_t* sem)
00330 {
00331 #if LWIP_TCPIP_CORE_LOCKING
00332   LWIP_UNUSED_ARG(sem);
00333   LOCK_TCPIP_CORE();
00334   fn(apimsg);
00335   UNLOCK_TCPIP_CORE();
00336   return ERR_OK;
00337 #else /* LWIP_TCPIP_CORE_LOCKING */
00338   TCPIP_MSG_VAR_DECLARE(msg);
00339 
00340   LWIP_ASSERT("semaphore not initialized", sys_sem_valid(sem));
00341   LWIP_ASSERT("Invalid mbox", sys_mbox_valid_val(mbox));
00342 
00343   TCPIP_MSG_VAR_ALLOC(msg);
00344   TCPIP_MSG_VAR_REF(msg).type = TCPIP_MSG_API;
00345   TCPIP_MSG_VAR_REF(msg).msg.api_msg.function = fn;
00346   TCPIP_MSG_VAR_REF(msg).msg.api_msg.msg = apimsg;
00347   sys_mbox_post(&mbox, &TCPIP_MSG_VAR_REF(msg));
00348   sys_arch_sem_wait(sem, 0);
00349   TCPIP_MSG_VAR_FREE(msg);
00350   return ERR_OK;
00351 #endif /* LWIP_TCPIP_CORE_LOCKING */
00352 }
00353 
00354 /**
00355  * Synchronously calls function in TCPIP thread and waits for its completion.
00356  * It is recommended to use LWIP_TCPIP_CORE_LOCKING (preferred) or
00357  * LWIP_NETCONN_SEM_PER_THREAD. 
00358  * If not, a semaphore is created and destroyed on every call which is usually
00359  * an expensive/slow operation.
00360  * @param fn Function to call
00361  * @param call Call parameters
00362  * @return Return value from tcpip_api_call_fn
00363  */
00364 err_t
00365 tcpip_api_call(tcpip_api_call_fn fn, struct tcpip_api_call_data *call)
00366 {
00367 #if LWIP_TCPIP_CORE_LOCKING
00368   err_t err;
00369   LOCK_TCPIP_CORE();
00370   err = fn(call);
00371   UNLOCK_TCPIP_CORE();
00372   return err;
00373 #else /* LWIP_TCPIP_CORE_LOCKING */
00374   TCPIP_MSG_VAR_DECLARE(msg);
00375 
00376 #if !LWIP_NETCONN_SEM_PER_THREAD
00377   err_t err = sys_sem_new(&call->sem, 0);
00378   if (err != ERR_OK) {
00379     return err;
00380   }
00381 #endif /* LWIP_NETCONN_SEM_PER_THREAD */
00382 
00383   LWIP_ASSERT("Invalid mbox", sys_mbox_valid_val(mbox));
00384 
00385   TCPIP_MSG_VAR_ALLOC(msg);
00386   TCPIP_MSG_VAR_REF(msg).type = TCPIP_MSG_API_CALL;
00387   TCPIP_MSG_VAR_REF(msg).msg.api_call.arg = call;
00388   TCPIP_MSG_VAR_REF(msg).msg.api_call.function = fn;
00389 #if LWIP_NETCONN_SEM_PER_THREAD
00390   TCPIP_MSG_VAR_REF(msg).msg.api_call.sem = LWIP_NETCONN_THREAD_SEM_GET();
00391 #else /* LWIP_NETCONN_SEM_PER_THREAD */
00392   TCPIP_MSG_VAR_REF(msg).msg.api_call.sem = &call->sem;
00393 #endif /* LWIP_NETCONN_SEM_PER_THREAD */
00394   sys_mbox_post(&mbox, &TCPIP_MSG_VAR_REF(msg));
00395   sys_arch_sem_wait(TCPIP_MSG_VAR_REF(msg).msg.api_call.sem, 0);
00396   TCPIP_MSG_VAR_FREE(msg);
00397 
00398 #if !LWIP_NETCONN_SEM_PER_THREAD
00399   sys_sem_free(&call->sem);
00400 #endif /* LWIP_NETCONN_SEM_PER_THREAD */
00401 
00402   return call->err;
00403 #endif /* LWIP_TCPIP_CORE_LOCKING */
00404 }
00405 
00406 /**
00407  * Allocate a structure for a static callback message and initialize it.
00408  * This is intended to be used to send "static" messages from interrupt context.
00409  *
00410  * @param function the function to call
00411  * @param ctx parameter passed to function
00412  * @return a struct pointer to pass to tcpip_trycallback().
00413  */
00414 struct tcpip_callback_msg*
00415 tcpip_callbackmsg_new(tcpip_callback_fn function, void *ctx)
00416 {
00417   struct tcpip_msg *msg = (struct tcpip_msg *)memp_malloc(MEMP_TCPIP_MSG_API);
00418   if (msg == NULL) {
00419     return NULL;
00420   }
00421   msg->type = TCPIP_MSG_CALLBACK_STATIC;
00422   msg->msg.cb.function = function;
00423   msg->msg.cb.ctx = ctx;
00424   return (struct tcpip_callback_msg*)msg;
00425 }
00426 
00427 /**
00428  * Free a callback message allocated by tcpip_callbackmsg_new().
00429  *
00430  * @param msg the message to free
00431  */
00432 void
00433 tcpip_callbackmsg_delete(struct tcpip_callback_msg* msg)
00434 {
00435   memp_free(MEMP_TCPIP_MSG_API, msg);
00436 }
00437 
00438 /**
00439  * Try to post a callback-message to the tcpip_thread mbox
00440  * This is intended to be used to send "static" messages from interrupt context.
00441  *
00442  * @param msg pointer to the message to post
00443  * @return sys_mbox_trypost() return code
00444  */
00445 err_t
00446 tcpip_trycallback(struct tcpip_callback_msg* msg)
00447 {
00448   LWIP_ASSERT("Invalid mbox", sys_mbox_valid_val(mbox));
00449   return sys_mbox_trypost(&mbox, msg);
00450 }
00451 
00452 /**
00453  * @ingroup lwip_os
00454  * Initialize this module:
00455  * - initialize all sub modules
00456  * - start the tcpip_thread
00457  *
00458  * @param initfunc a function to call when tcpip_thread is running and finished initializing
00459  * @param arg argument to pass to initfunc
00460  */
00461 void
00462 tcpip_init(tcpip_init_done_fn initfunc, void *arg)
00463 {
00464   lwip_init();
00465 
00466   tcpip_init_done = initfunc;
00467   tcpip_init_done_arg = arg;
00468   if (sys_mbox_new(&mbox, TCPIP_MBOX_SIZE) != ERR_OK) {
00469     LWIP_ASSERT("failed to create tcpip_thread mbox", 0);
00470   }
00471 #if LWIP_TCPIP_CORE_LOCKING
00472   if (sys_mutex_new(&lock_tcpip_core) != ERR_OK) {
00473     LWIP_ASSERT("failed to create lock_tcpip_core", 0);
00474   }
00475 #endif /* LWIP_TCPIP_CORE_LOCKING */
00476 
00477   sys_thread_new(TCPIP_THREAD_NAME, tcpip_thread, NULL, TCPIP_THREAD_STACKSIZE, TCPIP_THREAD_PRIO);
00478 }
00479 
00480 /**
00481  * Simple callback function used with tcpip_callback to free a pbuf
00482  * (pbuf_free has a wrong signature for tcpip_callback)
00483  *
00484  * @param p The pbuf (chain) to be dereferenced.
00485  */
00486 static void
00487 pbuf_free_int(void *p)
00488 {
00489   struct pbuf *q = (struct pbuf *)p;
00490   pbuf_free(q);
00491 }
00492 
00493 /**
00494  * A simple wrapper function that allows you to free a pbuf from interrupt context.
00495  *
00496  * @param p The pbuf (chain) to be dereferenced.
00497  * @return ERR_OK if callback could be enqueued, an err_t if not
00498  */
00499 err_t
00500 pbuf_free_callback(struct pbuf *p)
00501 {
00502   return tcpip_callback_with_block(pbuf_free_int, p, 0);
00503 }
00504 
00505 /**
00506  * A simple wrapper function that allows you to free heap memory from
00507  * interrupt context.
00508  *
00509  * @param m the heap memory to free
00510  * @return ERR_OK if callback could be enqueued, an err_t if not
00511  */
00512 err_t
00513 mem_free_callback(void *m)
00514 {
00515   return tcpip_callback_with_block(mem_free, m, 0);
00516 }
00517 
00518 #endif /* !NO_SYS */