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  1. /*
  2.  * Copyright (c) 2006 Ondrej Palkovsky
  3.  * All rights reserved.
  4.  *
  5.  * Redistribution and use in source and binary forms, with or without
  6.  * modification, are permitted provided that the following conditions
  7.  * are met:
  8.  *
  9.  * - Redistributions of source code must retain the above copyright
  10.  *   notice, this list of conditions and the following disclaimer.
  11.  * - Redistributions in binary form must reproduce the above copyright
  12.  *   notice, this list of conditions and the following disclaimer in the
  13.  *   documentation and/or other materials provided with the distribution.
  14.  * - The name of the author may not be used to endorse or promote products
  15.  *   derived from this software without specific prior written permission.
  16.  *
  17.  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18.  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19.  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20.  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21.  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22.  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23.  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24.  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25.  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26.  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27.  */
  28.  
  29. /** @addtogroup genericipc
  30.  * @{
  31.  */
  32. /** @file
  33.  */
  34.  
  35. #include <arch.h>
  36. #include <proc/task.h>
  37. #include <proc/thread.h>
  38. #include <errno.h>
  39. #include <memstr.h>
  40. #include <debug.h>
  41. #include <ipc/ipc.h>
  42. #include <ipc/sysipc.h>
  43. #include <ipc/irq.h>
  44. #include <ipc/ipcrsc.h>
  45. #include <ipc/kbox.h>
  46. #include <udebug/udebug_ipc.h>
  47. #include <arch/interrupt.h>
  48. #include <syscall/copy.h>
  49. #include <security/cap.h>
  50. #include <mm/as.h>
  51. #include <print.h>
  52.  
  53. /**
  54.  * Maximum buffer size allowed for IPC_M_DATA_WRITE and IPC_M_DATA_READ
  55.  * requests.
  56.  */
  57. #define DATA_XFER_LIMIT     (64 * 1024)
  58.  
  59. #define GET_CHECK_PHONE(phone, phoneid, err) \
  60. { \
  61.     if (phoneid > IPC_MAX_PHONES) { \
  62.         err; \
  63.     } \
  64.     phone = &TASK->phones[phoneid]; \
  65. }
  66.  
  67. #define STRUCT_TO_USPACE(dst, src)  copy_to_uspace(dst, src, sizeof(*(src)))
  68.  
  69. /** Decide if the method is a system method.
  70.  *
  71.  * @param method    Method to be decided.
  72.  *
  73.  * @return      Return 1 if the method is a system method.
  74.  *          Otherwise return 0.
  75.  */
  76. static inline int method_is_system(unative_t method)
  77. {
  78.     if (method <= IPC_M_LAST_SYSTEM)
  79.         return 1;
  80.     return 0;
  81. }
  82.  
  83. /** Decide if the message with this method is forwardable.
  84.  *
  85.  * - some system messages may be forwarded, for some of them
  86.  *   it is useless
  87.  *
  88.  * @param method    Method to be decided.
  89.  *
  90.  * @return      Return 1 if the method is forwardable.
  91.  *          Otherwise return 0.
  92.  */
  93. static inline int method_is_forwardable(unative_t method)
  94. {
  95.     switch (method) {
  96.     case IPC_M_PHONE_HUNGUP:
  97.         /* This message is meant only for the original recipient. */
  98.         return 0;
  99.     default:
  100.         return 1;
  101.     }
  102. }
  103.  
  104. /** Decide if the message with this method is immutable on forward.
  105.  *
  106.  * - some system messages may be forwarded but their content cannot be altered
  107.  *
  108.  * @param method    Method to be decided.
  109.  *
  110.  * @return      Return 1 if the method is immutable on forward.
  111.  *          Otherwise return 0.
  112.  */
  113. static inline int method_is_immutable(unative_t method)
  114. {
  115.     switch (method) {
  116.     case IPC_M_SHARE_OUT:
  117.     case IPC_M_SHARE_IN:
  118.     case IPC_M_DATA_WRITE:
  119.     case IPC_M_DATA_READ:
  120.         return 1;
  121.         break;
  122.     default:
  123.         return 0;
  124.     }
  125. }
  126.  
  127.  
  128. /***********************************************************************
  129.  * Functions that preprocess answer before sending it to the recepient.
  130.  ***********************************************************************/
  131.  
  132. /** Decide if the caller (e.g. ipc_answer()) should save the old call contents
  133.  * for answer_preprocess().
  134.  *
  135.  * @param call      Call structure to be decided.
  136.  *
  137.  * @return      Return 1 if the old call contents should be saved.
  138.  *          Return 0 otherwise.
  139.  */
  140. static inline int answer_need_old(call_t *call)
  141. {
  142.     switch (IPC_GET_METHOD(call->data)) {
  143.     case IPC_M_CONNECT_TO_ME:
  144.     case IPC_M_CONNECT_ME_TO:
  145.     case IPC_M_SHARE_OUT:
  146.     case IPC_M_SHARE_IN:
  147.     case IPC_M_DATA_WRITE:
  148.     case IPC_M_DATA_READ:
  149.         return 1;
  150.     default:
  151.         return 0;
  152.     }
  153. }
  154.  
  155. /** Interpret process answer as control information.
  156.  *
  157.  * This function is called directly after sys_ipc_answer().
  158.  *
  159.  * @param answer    Call structure with the answer.
  160.  * @param olddata   Saved data of the request.
  161.  *
  162.  * @return      Return 0 on success or an error code.
  163.  */
  164. static inline int answer_preprocess(call_t *answer, ipc_data_t *olddata)
  165. {
  166.     int phoneid;
  167.  
  168.     if ((native_t) IPC_GET_RETVAL(answer->data) == EHANGUP) {
  169.         /* In case of forward, hangup the forwared phone,
  170.          * not the originator
  171.          */
  172.         mutex_lock(&answer->data.phone->lock);
  173.         spinlock_lock(&TASK->answerbox.lock);
  174.         if (answer->data.phone->state == IPC_PHONE_CONNECTED) {
  175.             list_remove(&answer->data.phone->link);
  176.             answer->data.phone->state = IPC_PHONE_SLAMMED;
  177.         }
  178.         spinlock_unlock(&TASK->answerbox.lock);
  179.         mutex_unlock(&answer->data.phone->lock);
  180.     }
  181.  
  182.     if (!olddata)
  183.         return 0;
  184.  
  185.     if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_TO_ME) {
  186.         phoneid = IPC_GET_ARG5(*olddata);
  187.         if (IPC_GET_RETVAL(answer->data)) {
  188.             /* The connection was not accepted */
  189.             phone_dealloc(phoneid);
  190.         } else {
  191.             /* The connection was accepted */
  192.             phone_connect(phoneid, &answer->sender->answerbox);
  193.             /* Set 'phone hash' as arg5 of response */
  194.             IPC_SET_ARG5(answer->data,
  195.                 (unative_t) &TASK->phones[phoneid]);
  196.         }
  197.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME_TO) {
  198.         /* If the users accepted call, connect */
  199.         if (!IPC_GET_RETVAL(answer->data)) {
  200.             ipc_phone_connect((phone_t *) IPC_GET_ARG5(*olddata),
  201.                 &TASK->answerbox);
  202.         }
  203.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_SHARE_OUT) {
  204.         if (!IPC_GET_RETVAL(answer->data)) {
  205.             /* Accepted, handle as_area receipt */
  206.             ipl_t ipl;
  207.             int rc;
  208.             as_t *as;
  209.            
  210.             ipl = interrupts_disable();
  211.             spinlock_lock(&answer->sender->lock);
  212.             as = answer->sender->as;
  213.             spinlock_unlock(&answer->sender->lock);
  214.             interrupts_restore(ipl);
  215.            
  216.             rc = as_area_share(as, IPC_GET_ARG1(*olddata),
  217.                 IPC_GET_ARG2(*olddata), AS,
  218.                 IPC_GET_ARG1(answer->data), IPC_GET_ARG3(*olddata));
  219.             IPC_SET_RETVAL(answer->data, rc);
  220.             return rc;
  221.         }
  222.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_SHARE_IN) {
  223.         if (!IPC_GET_RETVAL(answer->data)) {
  224.             ipl_t ipl;
  225.             as_t *as;
  226.             int rc;
  227.            
  228.             ipl = interrupts_disable();
  229.             spinlock_lock(&answer->sender->lock);
  230.             as = answer->sender->as;
  231.             spinlock_unlock(&answer->sender->lock);
  232.             interrupts_restore(ipl);
  233.            
  234.             rc = as_area_share(AS, IPC_GET_ARG1(answer->data),
  235.                 IPC_GET_ARG2(*olddata), as, IPC_GET_ARG1(*olddata),
  236.                 IPC_GET_ARG2(answer->data));
  237.             IPC_SET_RETVAL(answer->data, rc);
  238.         }
  239.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_DATA_READ) {
  240.         ASSERT(!answer->buffer);
  241.         if (!IPC_GET_RETVAL(answer->data)) {
  242.             /* The recipient agreed to send data. */
  243.             uintptr_t src = IPC_GET_ARG1(answer->data);
  244.             uintptr_t dst = IPC_GET_ARG1(*olddata);
  245.             size_t max_size = IPC_GET_ARG2(*olddata);
  246.             size_t size = IPC_GET_ARG2(answer->data);
  247.             if (size && size <= max_size) {
  248.                 /*
  249.                  * Copy the destination VA so that this piece of
  250.                  * information is not lost.
  251.                  */
  252.                 IPC_SET_ARG1(answer->data, dst);
  253.  
  254.                 answer->buffer = malloc(size, 0);
  255.                 int rc = copy_from_uspace(answer->buffer,
  256.                     (void *) src, size);
  257.                 if (rc) {
  258.                     IPC_SET_RETVAL(answer->data, rc);
  259.                     free(answer->buffer);
  260.                     answer->buffer = NULL;
  261.                 }
  262.             } else if (!size) {
  263.                 IPC_SET_RETVAL(answer->data, EOK);
  264.             } else {
  265.                 IPC_SET_RETVAL(answer->data, ELIMIT);
  266.             }
  267.         }
  268.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_DATA_WRITE) {
  269.         ASSERT(answer->buffer);
  270.         if (!IPC_GET_RETVAL(answer->data)) {
  271.             /* The recipient agreed to receive data. */
  272.             int rc;
  273.             uintptr_t dst;
  274.             size_t size;
  275.             size_t max_size;
  276.  
  277.             dst = (uintptr_t)IPC_GET_ARG1(answer->data);
  278.             size = (size_t)IPC_GET_ARG2(answer->data);
  279.             max_size = (size_t)IPC_GET_ARG2(*olddata);
  280.  
  281.             if (size <= max_size) {
  282.                 rc = copy_to_uspace((void *) dst,
  283.                     answer->buffer, size);
  284.                 if (rc)
  285.                     IPC_SET_RETVAL(answer->data, rc);
  286.             } else {
  287.                 IPC_SET_RETVAL(answer->data, ELIMIT);
  288.             }
  289.         }
  290.         free(answer->buffer);
  291.         answer->buffer = NULL;
  292.     }
  293.     return 0;
  294. }
  295.  
  296. /** Called before the request is sent.
  297.  *
  298.  * @param call      Call structure with the request.
  299.  * @param phone     Phone that the call will be sent through.
  300.  *
  301.  * @return      Return 0 on success, ELIMIT or EPERM on error.
  302.  */
  303. static int request_preprocess(call_t *call, phone_t *phone)
  304. {
  305.     int newphid;
  306.     size_t size;
  307.     uintptr_t src;
  308.     int rc;
  309.  
  310.     switch (IPC_GET_METHOD(call->data)) {
  311.     case IPC_M_CONNECT_ME_TO:
  312.         newphid = phone_alloc();
  313.         if (newphid < 0)
  314.             return ELIMIT;
  315.         /* Set arg5 for server */
  316.         IPC_SET_ARG5(call->data, (unative_t) &TASK->phones[newphid]);
  317.         call->flags |= IPC_CALL_CONN_ME_TO;
  318.         call->priv = newphid;
  319.         break;
  320.     case IPC_M_SHARE_OUT:
  321.         size = as_area_get_size(IPC_GET_ARG1(call->data));
  322.         if (!size)
  323.             return EPERM;
  324.         IPC_SET_ARG2(call->data, size);
  325.         break;
  326.     case IPC_M_DATA_READ:
  327.         size = IPC_GET_ARG2(call->data);
  328.         if ((size <= 0 || (size > DATA_XFER_LIMIT)))
  329.             return ELIMIT;
  330.         break;
  331.     case IPC_M_DATA_WRITE:
  332.         src = IPC_GET_ARG1(call->data);
  333.         size = IPC_GET_ARG2(call->data);
  334.        
  335.         if ((size <= 0) || (size > DATA_XFER_LIMIT))
  336.             return ELIMIT;
  337.        
  338.         call->buffer = (uint8_t *) malloc(size, 0);
  339.         rc = copy_from_uspace(call->buffer, (void *) src, size);
  340.         if (rc != 0) {
  341.             free(call->buffer);
  342.             return rc;
  343.         }
  344.         break;
  345. #ifdef CONFIG_UDEBUG
  346.     case IPC_M_DEBUG_ALL:
  347.         return udebug_request_preprocess(call, phone);
  348. #endif
  349.     default:
  350.         break;
  351.     }
  352.     return 0;
  353. }
  354.  
  355. /*******************************************************************************
  356.  * Functions called to process received call/answer before passing it to uspace.
  357.  *******************************************************************************/
  358.  
  359. /** Do basic kernel processing of received call answer.
  360.  *
  361.  * @param call      Call structure with the answer.
  362.  */
  363. static void process_answer(call_t *call)
  364. {
  365.     if (((native_t) IPC_GET_RETVAL(call->data) == EHANGUP) &&
  366.         (call->flags & IPC_CALL_FORWARDED))
  367.         IPC_SET_RETVAL(call->data, EFORWARD);
  368.  
  369.     if (call->flags & IPC_CALL_CONN_ME_TO) {
  370.         if (IPC_GET_RETVAL(call->data))
  371.             phone_dealloc(call->priv);
  372.         else
  373.             IPC_SET_ARG5(call->data, call->priv);
  374.     }
  375.  
  376.     if (call->buffer) {
  377.         /* This must be an affirmative answer to IPC_M_DATA_READ. */
  378.         /* or IPC_M_DEBUG_ALL/UDEBUG_M_MEM_READ... */
  379.         uintptr_t dst = IPC_GET_ARG1(call->data);
  380.         size_t size = IPC_GET_ARG2(call->data);
  381.         int rc = copy_to_uspace((void *) dst, call->buffer, size);
  382.         if (rc)
  383.             IPC_SET_RETVAL(call->data, rc);
  384.         free(call->buffer);
  385.         call->buffer = NULL;
  386.     }
  387. }
  388.  
  389. /** Do basic kernel processing of received call request.
  390.  *
  391.  * @param box       Destination answerbox structure.
  392.  * @param call      Call structure with the request.
  393.  *
  394.  * @return      Return 0 if the call should be passed to userspace.
  395.  *          Return -1 if the call should be ignored.
  396.  */
  397. static int process_request(answerbox_t *box, call_t *call)
  398. {
  399.     int phoneid;
  400.  
  401.     if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME) {
  402.         phoneid = phone_alloc();
  403.         if (phoneid < 0) { /* Failed to allocate phone */
  404.             IPC_SET_RETVAL(call->data, ELIMIT);
  405.             ipc_answer(box, call);
  406.             return -1;
  407.         }
  408.         IPC_SET_ARG5(call->data, phoneid);
  409.     }
  410.     switch (IPC_GET_METHOD(call->data)) {
  411.     case IPC_M_DEBUG_ALL:
  412.         return -1;
  413.     default:
  414.         break;
  415.     }
  416.     return 0;
  417. }
  418.  
  419. /** Make a fast call over IPC, wait for reply and return to user.
  420.  *
  421.  * This function can handle only three arguments of payload, but is faster than
  422.  * the generic function (i.e. sys_ipc_call_sync_slow()).
  423.  *
  424.  * @param phoneid   Phone handle for the call.
  425.  * @param method    Method of the call.
  426.  * @param arg1      Service-defined payload argument.
  427.  * @param arg2      Service-defined payload argument.
  428.  * @param arg3      Service-defined payload argument.
  429.  * @param data      Address of userspace structure where the reply call will
  430.  *          be stored.
  431.  *
  432.  * @return      Returns 0 on success.
  433.  *          Return ENOENT if there is no such phone handle.
  434.  */
  435. unative_t sys_ipc_call_sync_fast(unative_t phoneid, unative_t method,
  436.     unative_t arg1, unative_t arg2, unative_t arg3, ipc_data_t *data)
  437. {
  438.     call_t call;
  439.     phone_t *phone;
  440.     int res;
  441.     int rc;
  442.    
  443.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  444.  
  445.     ipc_call_static_init(&call);
  446.     IPC_SET_METHOD(call.data, method);
  447.     IPC_SET_ARG1(call.data, arg1);
  448.     IPC_SET_ARG2(call.data, arg2);
  449.     IPC_SET_ARG3(call.data, arg3);
  450.     /*
  451.      * To achieve deterministic behavior, zero out arguments that are beyond
  452.      * the limits of the fast version.
  453.      */
  454.     IPC_SET_ARG4(call.data, 0);
  455.     IPC_SET_ARG5(call.data, 0);
  456.  
  457.     if (!(res = request_preprocess(&call, phone))) {
  458. #ifdef CONFIG_UDEBUG
  459.         udebug_stoppable_begin();
  460. #endif
  461.         rc = ipc_call_sync(phone, &call);
  462. #ifdef CONFIG_UDEBUG
  463.         udebug_stoppable_end();
  464. #endif
  465.         if (rc != EOK)
  466.             return rc;
  467.         process_answer(&call);
  468.  
  469.     } else {
  470.         IPC_SET_RETVAL(call.data, res);
  471.     }
  472.     rc = STRUCT_TO_USPACE(&data->args, &call.data.args);
  473.     if (rc != 0)
  474.         return rc;
  475.  
  476.     return 0;
  477. }
  478.  
  479. /** Make a synchronous IPC call allowing to transmit the entire payload.
  480.  *
  481.  * @param phoneid   Phone handle for the call.
  482.  * @param question  Userspace address of call data with the request.
  483.  * @param reply     Userspace address of call data where to store the
  484.  *          answer.
  485.  *
  486.  * @return      Zero on success or an error code.
  487.  */
  488. unative_t sys_ipc_call_sync_slow(unative_t phoneid, ipc_data_t *question,
  489.     ipc_data_t *reply)
  490. {
  491.     call_t call;
  492.     phone_t *phone;
  493.     int res;
  494.     int rc;
  495.  
  496.     ipc_call_static_init(&call);
  497.     rc = copy_from_uspace(&call.data.args, &question->args,
  498.         sizeof(call.data.args));
  499.     if (rc != 0)
  500.         return (unative_t) rc;
  501.  
  502.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  503.  
  504.     if (!(res = request_preprocess(&call, phone))) {
  505. #ifdef CONFIG_UDEBUG
  506.         udebug_stoppable_begin();
  507. #endif
  508.         rc = ipc_call_sync(phone, &call);
  509. #ifdef CONFIG_UDEBUG
  510.         udebug_stoppable_end();
  511. #endif
  512.         if (rc != EOK)
  513.             return rc;
  514.         process_answer(&call);
  515.     } else
  516.         IPC_SET_RETVAL(call.data, res);
  517.  
  518.     rc = STRUCT_TO_USPACE(&reply->args, &call.data.args);
  519.     if (rc != 0)
  520.         return rc;
  521.  
  522.     return 0;
  523. }
  524.  
  525. /** Check that the task did not exceed the allowed limit of asynchronous calls.
  526.  *
  527.  * @return      Return 0 if limit not reached or -1 if limit exceeded.
  528.  */
  529. static int check_call_limit(void)
  530. {
  531.     if (atomic_preinc(&TASK->active_calls) > IPC_MAX_ASYNC_CALLS) {
  532.         atomic_dec(&TASK->active_calls);
  533.         return -1;
  534.     }
  535.     return 0;
  536. }
  537.  
  538. /** Make a fast asynchronous call over IPC.
  539.  *
  540.  * This function can only handle four arguments of payload, but is faster than
  541.  * the generic function sys_ipc_call_async_slow().
  542.  *
  543.  * @param phoneid   Phone handle for the call.
  544.  * @param method    Method of the call.
  545.  * @param arg1      Service-defined payload argument.
  546.  * @param arg2      Service-defined payload argument.
  547.  * @param arg3      Service-defined payload argument.
  548.  * @param arg4      Service-defined payload argument.
  549.  *
  550.  * @return      Return call hash on success.
  551.  *          Return IPC_CALLRET_FATAL in case of a fatal error and
  552.  *          IPC_CALLRET_TEMPORARY if there are too many pending
  553.  *          asynchronous requests; answers should be handled first.
  554.  */
  555. unative_t sys_ipc_call_async_fast(unative_t phoneid, unative_t method,
  556.     unative_t arg1, unative_t arg2, unative_t arg3, unative_t arg4)
  557. {
  558.     call_t *call;
  559.     phone_t *phone;
  560.     int res;
  561.  
  562.     if (check_call_limit())
  563.         return IPC_CALLRET_TEMPORARY;
  564.  
  565.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  566.  
  567.     call = ipc_call_alloc(0);
  568.     IPC_SET_METHOD(call->data, method);
  569.     IPC_SET_ARG1(call->data, arg1);
  570.     IPC_SET_ARG2(call->data, arg2);
  571.     IPC_SET_ARG3(call->data, arg3);
  572.     IPC_SET_ARG4(call->data, arg4);
  573.     /*
  574.      * To achieve deterministic behavior, zero out arguments that are beyond
  575.      * the limits of the fast version.
  576.      */
  577.     IPC_SET_ARG5(call->data, 0);
  578.  
  579.     if (!(res = request_preprocess(call, phone)))
  580.         ipc_call(phone, call);
  581.     else
  582.         ipc_backsend_err(phone, call, res);
  583.  
  584.     return (unative_t) call;
  585. }
  586.  
  587. /** Make an asynchronous IPC call allowing to transmit the entire payload.
  588.  *
  589.  * @param phoneid   Phone handle for the call.
  590.  * @param data      Userspace address of call data with the request.
  591.  *
  592.  * @return      See sys_ipc_call_async_fast().
  593.  */
  594. unative_t sys_ipc_call_async_slow(unative_t phoneid, ipc_data_t *data)
  595. {
  596.     call_t *call;
  597.     phone_t *phone;
  598.     int res;
  599.     int rc;
  600.  
  601.     if (check_call_limit())
  602.         return IPC_CALLRET_TEMPORARY;
  603.  
  604.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  605.  
  606.     call = ipc_call_alloc(0);
  607.     rc = copy_from_uspace(&call->data.args, &data->args,
  608.         sizeof(call->data.args));
  609.     if (rc != 0) {
  610.         ipc_call_free(call);
  611.         return (unative_t) rc;
  612.     }
  613.     if (!(res = request_preprocess(call, phone)))
  614.         ipc_call(phone, call);
  615.     else
  616.         ipc_backsend_err(phone, call, res);
  617.  
  618.     return (unative_t) call;
  619. }
  620.  
  621. /** Forward a received call to another destination.
  622.  *
  623.  * @param callid    Hash of the call to forward.
  624.  * @param phoneid   Phone handle to use for forwarding.
  625.  * @param method    New method to use for the forwarded call.
  626.  * @param arg1      New value of the first argument for the forwarded call.
  627.  * @param arg2      New value of the second argument for the forwarded call.
  628.  * @param mode      Flags that specify mode of the forward operation.
  629.  *
  630.  * @return      Return 0 on succes, otherwise return an error code.
  631.  *
  632.  * In case the original method is a system method, ARG1, ARG2 and ARG3 are
  633.  * overwritten in the forwarded message with the new method and the new arg1 and
  634.  * arg2, respectively. Otherwise the METHOD, ARG1 and ARG2 are rewritten with
  635.  * the new method, arg1 and arg2, respectively. Also note there is a set of
  636.  * immutable methods, for which the new method and argument is not set and
  637.  * these values are ignored.
  638.  *
  639.  * Warning: When implementing support for changing additional payload
  640.  *      arguments, make sure that ARG5 is not rewritten for certain
  641.  *      system IPC
  642.  */
  643. unative_t sys_ipc_forward_fast(unative_t callid, unative_t phoneid,
  644.     unative_t method, unative_t arg1, unative_t arg2, int mode)
  645. {
  646.     call_t *call;
  647.     phone_t *phone;
  648.  
  649.     call = get_call(callid);
  650.     if (!call)
  651.         return ENOENT;
  652.  
  653.     call->flags |= IPC_CALL_FORWARDED;
  654.  
  655.     GET_CHECK_PHONE(phone, phoneid, {
  656.         IPC_SET_RETVAL(call->data, EFORWARD);
  657.         ipc_answer(&TASK->answerbox, call);
  658.         return ENOENT;
  659.     });
  660.  
  661.     if (!method_is_forwardable(IPC_GET_METHOD(call->data))) {
  662.         IPC_SET_RETVAL(call->data, EFORWARD);
  663.         ipc_answer(&TASK->answerbox, call);
  664.         return EPERM;
  665.     }
  666.  
  667.     /*
  668.      * Userspace is not allowed to change method of system methods on
  669.      * forward, allow changing ARG1, ARG2 and ARG3 by means of method,
  670.      * arg1 and arg2.
  671.      * If the method is immutable, don't change anything.
  672.      */
  673.     if (!method_is_immutable(IPC_GET_METHOD(call->data))) {
  674.         if (method_is_system(IPC_GET_METHOD(call->data))) {
  675.             if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME)
  676.                 phone_dealloc(IPC_GET_ARG5(call->data));
  677.  
  678.             IPC_SET_ARG1(call->data, method);
  679.             IPC_SET_ARG2(call->data, arg1);
  680.             IPC_SET_ARG3(call->data, arg2);
  681.         } else {
  682.             IPC_SET_METHOD(call->data, method);
  683.             IPC_SET_ARG1(call->data, arg1);
  684.             IPC_SET_ARG2(call->data, arg2);
  685.         }
  686.     }
  687.  
  688.     return ipc_forward(call, phone, &TASK->answerbox, mode);
  689. }
  690.  
  691. /** Answer an IPC call - fast version.
  692.  *
  693.  * This function can handle only two return arguments of payload, but is faster
  694.  * than the generic sys_ipc_answer().
  695.  *
  696.  * @param callid    Hash of the call to be answered.
  697.  * @param retval    Return value of the answer.
  698.  * @param arg1      Service-defined return value.
  699.  * @param arg2      Service-defined return value.
  700.  * @param arg3      Service-defined return value.
  701.  * @param arg4      Service-defined return value.
  702.  *
  703.  * @return      Return 0 on success, otherwise return an error code.   
  704.  */
  705. unative_t sys_ipc_answer_fast(unative_t callid, unative_t retval,
  706.     unative_t arg1, unative_t arg2, unative_t arg3, unative_t arg4)
  707. {
  708.     call_t *call;
  709.     ipc_data_t saved_data;
  710.     int saveddata = 0;
  711.     int rc;
  712.  
  713.     /* Do not answer notification callids */
  714.     if (callid & IPC_CALLID_NOTIFICATION)
  715.         return 0;
  716.  
  717.     call = get_call(callid);
  718.     if (!call)
  719.         return ENOENT;
  720.  
  721.     if (answer_need_old(call)) {
  722.         memcpy(&saved_data, &call->data, sizeof(call->data));
  723.         saveddata = 1;
  724.     }
  725.  
  726.     IPC_SET_RETVAL(call->data, retval);
  727.     IPC_SET_ARG1(call->data, arg1);
  728.     IPC_SET_ARG2(call->data, arg2);
  729.     IPC_SET_ARG3(call->data, arg3);
  730.     IPC_SET_ARG4(call->data, arg4);
  731.     /*
  732.      * To achieve deterministic behavior, zero out arguments that are beyond
  733.      * the limits of the fast version.
  734.      */
  735.     IPC_SET_ARG5(call->data, 0);
  736.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  737.  
  738.     ipc_answer(&TASK->answerbox, call);
  739.     return rc;
  740. }
  741.  
  742. /** Answer an IPC call.
  743.  *
  744.  * @param callid    Hash of the call to be answered.
  745.  * @param data      Userspace address of call data with the answer.
  746.  *
  747.  * @return      Return 0 on success, otherwise return an error code.
  748.  */
  749. unative_t sys_ipc_answer_slow(unative_t callid, ipc_data_t *data)
  750. {
  751.     call_t *call;
  752.     ipc_data_t saved_data;
  753.     int saveddata = 0;
  754.     int rc;
  755.  
  756.     /* Do not answer notification callids */
  757.     if (callid & IPC_CALLID_NOTIFICATION)
  758.         return 0;
  759.  
  760.     call = get_call(callid);
  761.     if (!call)
  762.         return ENOENT;
  763.  
  764.     if (answer_need_old(call)) {
  765.         memcpy(&saved_data, &call->data, sizeof(call->data));
  766.         saveddata = 1;
  767.     }
  768.     rc = copy_from_uspace(&call->data.args, &data->args,
  769.         sizeof(call->data.args));
  770.     if (rc != 0)
  771.         return rc;
  772.  
  773.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  774.    
  775.     ipc_answer(&TASK->answerbox, call);
  776.  
  777.     return rc;
  778. }
  779.  
  780. /** Hang up a phone.
  781.  *
  782.  * @param       Phone handle of the phone to be hung up.
  783.  *
  784.  * @return      Return 0 on success or an error code.
  785.  */
  786. unative_t sys_ipc_hangup(int phoneid)
  787. {
  788.     phone_t *phone;
  789.  
  790.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  791.  
  792.     if (ipc_phone_hangup(phone))
  793.         return -1;
  794.  
  795.     return 0;
  796. }
  797.  
  798. /** Wait for an incoming IPC call or an answer.
  799.  *
  800.  * @param calldata  Pointer to buffer where the call/answer data is stored.
  801.  * @param usec      Timeout. See waitq_sleep_timeout() for explanation.
  802.  * @param flags     Select mode of sleep operation. See waitq_sleep_timeout()
  803.  *          for explanation.
  804.  *
  805.  * @return      Hash of the call.
  806.  *          If IPC_CALLID_NOTIFICATION bit is set in the hash, the
  807.  *          call is a notification. IPC_CALLID_ANSWERED denotes an
  808.  *          answer.
  809.  */
  810. unative_t sys_ipc_wait_for_call(ipc_data_t *calldata, uint32_t usec, int flags)
  811. {
  812.     call_t *call;
  813.  
  814. restart:
  815.  
  816. #ifdef CONFIG_UDEBUG
  817.     udebug_stoppable_begin();
  818. #endif 
  819.     call = ipc_wait_for_call(&TASK->answerbox, usec,
  820.         flags | SYNCH_FLAGS_INTERRUPTIBLE);
  821.  
  822. #ifdef CONFIG_UDEBUG
  823.     udebug_stoppable_end();
  824. #endif
  825.     if (!call)
  826.         return 0;
  827.  
  828.     if (call->flags & IPC_CALL_NOTIF) {
  829.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  830.  
  831.         /* Set in_phone_hash to the interrupt counter */
  832.         call->data.phone = (void *) call->priv;
  833.        
  834.         STRUCT_TO_USPACE(calldata, &call->data);
  835.  
  836.         ipc_call_free(call);
  837.        
  838.         return ((unative_t) call) | IPC_CALLID_NOTIFICATION;
  839.     }
  840.  
  841.     if (call->flags & IPC_CALL_ANSWERED) {
  842.         process_answer(call);
  843.  
  844.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  845.  
  846.         if (call->flags & IPC_CALL_DISCARD_ANSWER) {
  847.             ipc_call_free(call);
  848.             goto restart;
  849.         } else {
  850.             /*
  851.              * Decrement the counter of active calls only if the
  852.              * call is not an answer to IPC_M_PHONE_HUNGUP,
  853.              * which doesn't contribute to the counter.
  854.              */
  855.             atomic_dec(&TASK->active_calls);
  856.         }
  857.  
  858.         STRUCT_TO_USPACE(&calldata->args, &call->data.args);
  859.         ipc_call_free(call);
  860.  
  861.         return ((unative_t) call) | IPC_CALLID_ANSWERED;
  862.     }
  863.  
  864.     if (process_request(&TASK->answerbox, call))
  865.         goto restart;
  866.  
  867.     /* Include phone address('id') of the caller in the request,
  868.      * copy whole call->data, not only call->data.args */
  869.     if (STRUCT_TO_USPACE(calldata, &call->data)) {
  870.         return 0;
  871.     }
  872.     return (unative_t)call;
  873. }
  874.  
  875. /** Connect an IRQ handler to a task.
  876.  *
  877.  * @param inr       IRQ number.
  878.  * @param devno     Device number.
  879.  * @param method    Method to be associated with the notification.
  880.  * @param ucode     Uspace pointer to the top-half pseudocode.
  881.  *
  882.  * @return      EPERM or a return code returned by ipc_irq_register().
  883.  */
  884. unative_t sys_ipc_register_irq(inr_t inr, devno_t devno, unative_t method,
  885.     irq_code_t *ucode)
  886. {
  887.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  888.         return EPERM;
  889.  
  890.     return ipc_irq_register(&TASK->answerbox, inr, devno, method, ucode);
  891. }
  892.  
  893. /** Disconnect an IRQ handler from a task.
  894.  *
  895.  * @param inr       IRQ number.
  896.  * @param devno     Device number.
  897.  *
  898.  * @return      Zero on success or EPERM on error..
  899.  */
  900. unative_t sys_ipc_unregister_irq(inr_t inr, devno_t devno)
  901. {
  902.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  903.         return EPERM;
  904.  
  905.     ipc_irq_unregister(&TASK->answerbox, inr, devno);
  906.  
  907.     return 0;
  908. }
  909.  
  910. #include <console/console.h>
  911.  
  912. /**
  913.  * Syscall connect to a task by id.
  914.  *
  915.  * @return      Phone id on success, or negative error code.
  916.  */
  917. unative_t sys_ipc_connect_kbox(sysarg64_t *uspace_taskid_arg)
  918. {
  919. #ifdef CONFIG_UDEBUG
  920.     sysarg64_t taskid_arg;
  921.     int rc;
  922.    
  923.     rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
  924.     if (rc != 0)
  925.         return (unative_t) rc;
  926.  
  927.     LOG("sys_ipc_connect_kbox(%" PRIu64 ")\n", taskid_arg.value);
  928.  
  929.     return ipc_connect_kbox(taskid_arg.value);
  930. #else
  931.     return (unative_t) ENOTSUP;
  932. #endif
  933. }
  934.  
  935. /** @}
  936.  */
  937.