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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 <arch/interrupt.h>
  46. #include <print.h>
  47. #include <syscall/copy.h>
  48. #include <security/cap.h>
  49. #include <mm/as.h>
  50. #include <print.h>
  51.  
  52. /** Maximum buffer size allowed for IPC_M_DATA_SEND requests. */
  53. #define DATA_SEND_LIMIT     (64 * 1024)
  54.  
  55. #define GET_CHECK_PHONE(phone, phoneid, err) \
  56. { \
  57.     if (phoneid > IPC_MAX_PHONES) { \
  58.         err; \
  59.     } \
  60.     phone = &TASK->phones[phoneid]; \
  61. }
  62.  
  63. #define STRUCT_TO_USPACE(dst, src)  copy_to_uspace(dst, src, sizeof(*(src)))
  64.  
  65. /** Decide if the method is a system method.
  66.  *
  67.  * @param method    Method to be decided.
  68.  *
  69.  * @return      Return 1 if the method is a system method.
  70.  *          Otherwise return 0.
  71.  */
  72. static inline int is_system_method(unative_t method)
  73. {
  74.     if (method <= IPC_M_LAST_SYSTEM)
  75.         return 1;
  76.     return 0;
  77. }
  78.  
  79. /** Decide if the message with this method is forwardable.
  80.  *
  81.  * - some system messages may be forwarded, for some of them
  82.  *   it is useless
  83.  *
  84.  * @param method    Method to be decided.
  85.  *
  86.  * @return      Return 1 if the method is forwardable.
  87.  *          Otherwise return 0.
  88.  */
  89. static inline int is_forwardable(unative_t method)
  90. {
  91.     switch (method) {
  92.     case IPC_M_PHONE_HUNGUP:
  93.     case IPC_M_AS_AREA_SEND:
  94.     case IPC_M_AS_AREA_RECV:
  95.     case IPC_M_DATA_SEND:
  96.         /* This message is meant only for the original recipient. */
  97.         return 0;
  98.     default:
  99.         return 1;
  100.     }
  101. }
  102.  
  103.  
  104. /***********************************************************************
  105.  * Functions that preprocess answer before sending it to the recepient.
  106.  ***********************************************************************/
  107.  
  108. /** Decide if the caller (e.g. ipc_answer()) should save the old call contents
  109.  * for answer_preprocess().
  110.  *
  111.  * @param call      Call structure to be decided.
  112.  *
  113.  * @return      Return 1 if the old call contents should be saved.
  114.  *          Return 0 otherwise.
  115.  */
  116. static inline int answer_need_old(call_t *call)
  117. {
  118.     switch (IPC_GET_METHOD(call->data)) {
  119.     case IPC_M_CONNECT_TO_ME:
  120.     case IPC_M_CONNECT_ME_TO:
  121.     case IPC_M_AS_AREA_SEND:
  122.     case IPC_M_AS_AREA_RECV:
  123.     case IPC_M_DATA_SEND:
  124.         return 1;
  125.     default:
  126.         return 0;
  127.     }
  128. }
  129.  
  130. /** Interpret process answer as control information.
  131.  *
  132.  * This function is called directly after sys_ipc_answer().
  133.  *
  134.  * @param answer    Call structure with the answer.
  135.  * @param olddata   Saved data of the request.
  136.  *
  137.  * @return      Return 0 on success or an error code.
  138.  */
  139. static inline int answer_preprocess(call_t *answer, ipc_data_t *olddata)
  140. {
  141.     int phoneid;
  142.  
  143.     if (IPC_GET_RETVAL(answer->data) == EHANGUP) {
  144.         /* In case of forward, hangup the forwared phone,
  145.          * not the originator
  146.          */
  147.         spinlock_lock(&answer->data.phone->lock);
  148.         spinlock_lock(&TASK->answerbox.lock);
  149.         if (answer->data.phone->state == IPC_PHONE_CONNECTED) {
  150.             list_remove(&answer->data.phone->link);
  151.             answer->data.phone->state = IPC_PHONE_SLAMMED;
  152.         }
  153.         spinlock_unlock(&TASK->answerbox.lock);
  154.         spinlock_unlock(&answer->data.phone->lock);
  155.     }
  156.  
  157.     if (!olddata)
  158.         return 0;
  159.  
  160.     if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_TO_ME) {
  161.         phoneid = IPC_GET_ARG3(*olddata);
  162.         if (IPC_GET_RETVAL(answer->data)) {
  163.             /* The connection was not accepted */
  164.             phone_dealloc(phoneid);
  165.         } else {
  166.             /* The connection was accepted */
  167.             phone_connect(phoneid, &answer->sender->answerbox);
  168.             /* Set 'phone hash' as arg3 of response */
  169.             IPC_SET_ARG3(answer->data,
  170.                 (unative_t) &TASK->phones[phoneid]);
  171.         }
  172.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME_TO) {
  173.         /* If the users accepted call, connect */
  174.         if (!IPC_GET_RETVAL(answer->data)) {
  175.             ipc_phone_connect((phone_t *) IPC_GET_ARG3(*olddata),
  176.                 &TASK->answerbox);
  177.         }
  178.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_AS_AREA_SEND) {
  179.         if (!IPC_GET_RETVAL(answer->data)) {
  180.             /* Accepted, handle as_area receipt */
  181.             ipl_t ipl;
  182.             int rc;
  183.             as_t *as;
  184.            
  185.             ipl = interrupts_disable();
  186.             spinlock_lock(&answer->sender->lock);
  187.             as = answer->sender->as;
  188.             spinlock_unlock(&answer->sender->lock);
  189.             interrupts_restore(ipl);
  190.            
  191.             rc = as_area_share(as, IPC_GET_ARG1(*olddata),
  192.                 IPC_GET_ARG2(*olddata), AS,
  193.                 IPC_GET_ARG1(answer->data), IPC_GET_ARG3(*olddata));
  194.             IPC_SET_RETVAL(answer->data, rc);
  195.             return rc;
  196.         }
  197.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_AS_AREA_RECV) {
  198.         if (!IPC_GET_RETVAL(answer->data)) {
  199.             ipl_t ipl;
  200.             as_t *as;
  201.             int rc;
  202.            
  203.             ipl = interrupts_disable();
  204.             spinlock_lock(&answer->sender->lock);
  205.             as = answer->sender->as;
  206.             spinlock_unlock(&answer->sender->lock);
  207.             interrupts_restore(ipl);
  208.            
  209.             rc = as_area_share(AS, IPC_GET_ARG1(answer->data),
  210.                 IPC_GET_ARG2(*olddata), as, IPC_GET_ARG1(*olddata),
  211.                 IPC_GET_ARG2(answer->data));
  212.             IPC_SET_RETVAL(answer->data, rc);
  213.         }
  214.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_DATA_SEND) {
  215.         if (!IPC_GET_RETVAL(answer->data)) {
  216.             int rc;
  217.             uintptr_t dst;
  218.             uintptr_t size;
  219.  
  220.             ASSERT(answer->buffer);
  221.  
  222.             dst = IPC_GET_ARG1(answer->data);
  223.             size = IPC_GET_ARG3(answer->data);
  224.  
  225.             rc = copy_to_uspace((void *) dst, answer->buffer, size);
  226.             if (rc != 0)
  227.                 IPC_SET_RETVAL(answer->data, rc);
  228.             free(answer->buffer);
  229.             answer->buffer = NULL;
  230.         }
  231.     }
  232.     return 0;
  233. }
  234.  
  235. /** Called before the request is sent.
  236.  *
  237.  * @param call      Call structure with the request.
  238.  *
  239.  * @return      Return 0 on success, ELIMIT or EPERM on error.
  240.  */
  241. static int request_preprocess(call_t *call)
  242. {
  243.     int newphid;
  244.     size_t size;
  245.     uintptr_t src;
  246.     int rc;
  247.  
  248.     switch (IPC_GET_METHOD(call->data)) {
  249.     case IPC_M_CONNECT_ME_TO:
  250.         newphid = phone_alloc();
  251.         if (newphid < 0)
  252.             return ELIMIT;
  253.         /* Set arg3 for server */
  254.         IPC_SET_ARG3(call->data, (unative_t) &TASK->phones[newphid]);
  255.         call->flags |= IPC_CALL_CONN_ME_TO;
  256.         call->priv = newphid;
  257.         break;
  258.     case IPC_M_AS_AREA_SEND:
  259.         size = as_get_size(IPC_GET_ARG1(call->data));
  260.         if (!size)
  261.             return EPERM;
  262.         IPC_SET_ARG2(call->data, size);
  263.         break;
  264.     case IPC_M_DATA_SEND:
  265.         src = IPC_GET_ARG2(call->data);
  266.         size = IPC_GET_ARG3(call->data);
  267.        
  268.         if ((size <= 0) || (size > DATA_SEND_LIMIT))
  269.             return ELIMIT;
  270.        
  271.         call->buffer = (uint8_t *) malloc(size, 0);
  272.         rc = copy_from_uspace(call->buffer, (void *) src, size);
  273.         if (rc != 0) {
  274.             free(call->buffer);
  275.             return rc;
  276.         }
  277.         break;
  278.     default:
  279.         break;
  280.     }
  281.     return 0;
  282. }
  283.  
  284. /*******************************************************************************
  285.  * Functions called to process received call/answer before passing it to uspace.
  286.  *******************************************************************************/
  287.  
  288. /** Do basic kernel processing of received call answer.
  289.  *
  290.  * @param call      Call structure with the answer.
  291.  */
  292. static void process_answer(call_t *call)
  293. {
  294.     if (IPC_GET_RETVAL(call->data) == EHANGUP &&
  295.         (call->flags & IPC_CALL_FORWARDED))
  296.         IPC_SET_RETVAL(call->data, EFORWARD);
  297.  
  298.     if (call->flags & IPC_CALL_CONN_ME_TO) {
  299.         if (IPC_GET_RETVAL(call->data))
  300.             phone_dealloc(call->priv);
  301.         else
  302.             IPC_SET_ARG3(call->data, call->priv);
  303.     }
  304. }
  305.  
  306. /** Do basic kernel processing of received call request.
  307.  *
  308.  * @param box       Destination answerbox structure.
  309.  * @param call      Call structure with the request.
  310.  *
  311.  * @return      Return 0 if the call should be passed to userspace.
  312.  *          Return -1 if the call should be ignored.
  313.  */
  314. static int process_request(answerbox_t *box, call_t *call)
  315. {
  316.     int phoneid;
  317.  
  318.     if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME) {
  319.         phoneid = phone_alloc();
  320.         if (phoneid < 0) { /* Failed to allocate phone */
  321.             IPC_SET_RETVAL(call->data, ELIMIT);
  322.             ipc_answer(box, call);
  323.             return -1;
  324.         }
  325.         IPC_SET_ARG3(call->data, phoneid);
  326.     }
  327.     return 0;
  328. }
  329.  
  330. /** Make a fast call over IPC, wait for reply and return to user.
  331.  *
  332.  * This function can handle only one argument of payload, but is faster than
  333.  * the generic function (i.e. sys_ipc_call_sync()).
  334.  *
  335.  * @param phoneid   Phone handle for the call.
  336.  * @param method    Method of the call.
  337.  * @param arg1      Service-defined payload argument.
  338.  * @param data      Address of userspace structure where the reply call will
  339.  *          be stored.
  340.  *
  341.  * @return      Returns 0 on success.
  342.  *          Return ENOENT if there is no such phone handle.
  343.  */
  344. unative_t sys_ipc_call_sync_fast(unative_t phoneid, unative_t method,
  345.     unative_t arg1, ipc_data_t *data)
  346. {
  347.     call_t call;
  348.     phone_t *phone;
  349.     int res;
  350.  
  351.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  352.  
  353.     ipc_call_static_init(&call);
  354.     IPC_SET_METHOD(call.data, method);
  355.     IPC_SET_ARG1(call.data, arg1);
  356.  
  357.     if (!(res = request_preprocess(&call))) {
  358.         ipc_call_sync(phone, &call);
  359.         process_answer(&call);
  360.     } else {
  361.         IPC_SET_RETVAL(call.data, res);
  362.     }
  363.     STRUCT_TO_USPACE(&data->args, &call.data.args);
  364.  
  365.     return 0;
  366. }
  367.  
  368. /** Make a synchronous IPC call allowing to transmit the entire payload.
  369.  *
  370.  * @param phoneid   Phone handle for the call.
  371.  * @param question  Userspace address of call data with the request.
  372.  * @param reply     Userspace address of call data where to store the
  373.  *          answer.
  374.  *
  375.  * @return      Zero on success or an error code.
  376.  */
  377. unative_t sys_ipc_call_sync(unative_t phoneid, ipc_data_t *question,
  378.     ipc_data_t *reply)
  379. {
  380.     call_t call;
  381.     phone_t *phone;
  382.     int res;
  383.     int rc;
  384.  
  385.     ipc_call_static_init(&call);
  386.     rc = copy_from_uspace(&call.data.args, &question->args,
  387.         sizeof(call.data.args));
  388.     if (rc != 0)
  389.         return (unative_t) rc;
  390.  
  391.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  392.  
  393.     if (!(res = request_preprocess(&call))) {
  394.         ipc_call_sync(phone, &call);
  395.         process_answer(&call);
  396.     } else
  397.         IPC_SET_RETVAL(call.data, res);
  398.  
  399.     rc = STRUCT_TO_USPACE(&reply->args, &call.data.args);
  400.     if (rc != 0)
  401.         return rc;
  402.  
  403.     return 0;
  404. }
  405.  
  406. /** Check that the task did not exceed the allowed limit of asynchronous calls.
  407.  *
  408.  * @return      Return 0 if limit not reached or -1 if limit exceeded.
  409.  */
  410. static int check_call_limit(void)
  411. {
  412.     if (atomic_preinc(&TASK->active_calls) > IPC_MAX_ASYNC_CALLS) {
  413.         atomic_dec(&TASK->active_calls);
  414.         return -1;
  415.     }
  416.     return 0;
  417. }
  418.  
  419. /** Make a fast asynchronous call over IPC.
  420.  *
  421.  * This function can only handle two arguments of payload, but is faster than
  422.  * the generic function sys_ipc_call_async().
  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.  *
  429.  * @return      Return call hash on success.
  430.  *          Return IPC_CALLRET_FATAL in case of a fatal error and
  431.  *          IPC_CALLRET_TEMPORARY if there are too many pending
  432.  *          asynchronous requests; answers should be handled first.
  433.  */
  434. unative_t sys_ipc_call_async_fast(unative_t phoneid, unative_t method,
  435.     unative_t arg1, unative_t arg2)
  436. {
  437.     call_t *call;
  438.     phone_t *phone;
  439.     int res;
  440.  
  441.     if (check_call_limit())
  442.         return IPC_CALLRET_TEMPORARY;
  443.  
  444.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  445.  
  446.     call = ipc_call_alloc(0);
  447.     IPC_SET_METHOD(call->data, method);
  448.     IPC_SET_ARG1(call->data, arg1);
  449.     IPC_SET_ARG2(call->data, arg2);
  450.     IPC_SET_ARG3(call->data, 0);
  451.  
  452.     if (!(res = request_preprocess(call)))
  453.         ipc_call(phone, call);
  454.     else
  455.         ipc_backsend_err(phone, call, res);
  456.  
  457.     return (unative_t) call;
  458. }
  459.  
  460. /** Make an asynchronous IPC call allowing to transmit the entire payload.
  461.  *
  462.  * @param phoneid   Phone handle for the call.
  463.  * @param data      Userspace address of call data with the request.
  464.  *
  465.  * @return      See sys_ipc_call_async_fast().
  466.  */
  467. unative_t sys_ipc_call_async(unative_t phoneid, ipc_data_t *data)
  468. {
  469.     call_t *call;
  470.     phone_t *phone;
  471.     int res;
  472.     int rc;
  473.  
  474.     if (check_call_limit())
  475.         return IPC_CALLRET_TEMPORARY;
  476.  
  477.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  478.  
  479.     call = ipc_call_alloc(0);
  480.     rc = copy_from_uspace(&call->data.args, &data->args,
  481.         sizeof(call->data.args));
  482.     if (rc != 0) {
  483.         ipc_call_free(call);
  484.         return (unative_t) rc;
  485.     }
  486.     if (!(res = request_preprocess(call)))
  487.         ipc_call(phone, call);
  488.     else
  489.         ipc_backsend_err(phone, call, res);
  490.  
  491.     return (unative_t) call;
  492. }
  493.  
  494. /** Forward a received call to another destination.
  495.  *
  496.  * @param callid    Hash of the call to forward.
  497.  * @param phoneid   Phone handle to use for forwarding.
  498.  * @param method    New method to use for the forwarded call.
  499.  * @param arg1      New value of the first argument for the forwarded call.
  500.  *
  501.  * @return      Return 0 on succes, otherwise return an error code.
  502.  *
  503.  * In case the original method is a system method, ARG1 and ARG2 are overwritten
  504.  * in the forwarded message with the new method and the new arg1, respectively.
  505.  * Otherwise the METHOD and ARG1 are rewritten with the new method and arg1,
  506.  * respectively.
  507.  *
  508.  * Warning: If implementing non-fast version, make sure that
  509.  *          ARG3 is not rewritten for certain system IPC
  510.  */
  511. unative_t sys_ipc_forward_fast(unative_t callid, unative_t phoneid,
  512.     unative_t method, unative_t arg1)
  513. {
  514.     call_t *call;
  515.     phone_t *phone;
  516.  
  517.     call = get_call(callid);
  518.     if (!call)
  519.         return ENOENT;
  520.  
  521.     call->flags |= IPC_CALL_FORWARDED;
  522.  
  523.     GET_CHECK_PHONE(phone, phoneid, {
  524.         IPC_SET_RETVAL(call->data, EFORWARD);
  525.         ipc_answer(&TASK->answerbox, call);
  526.         return ENOENT;
  527.     });    
  528.  
  529.     if (!is_forwardable(IPC_GET_METHOD(call->data))) {
  530.         IPC_SET_RETVAL(call->data, EFORWARD);
  531.         ipc_answer(&TASK->answerbox, call);
  532.         return EPERM;
  533.     }
  534.  
  535.     /* Userspace is not allowed to change method of system methods
  536.      * on forward, allow changing ARG1 and ARG2 by means of method and arg1
  537.      */
  538.     if (is_system_method(IPC_GET_METHOD(call->data))) {
  539.         if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME)
  540.             phone_dealloc(IPC_GET_ARG3(call->data));
  541.  
  542.         IPC_SET_ARG1(call->data, method);
  543.         IPC_SET_ARG2(call->data, arg1);
  544.     } else {
  545.         IPC_SET_METHOD(call->data, method);
  546.         IPC_SET_ARG1(call->data, arg1);
  547.     }
  548.  
  549.     return ipc_forward(call, phone, &TASK->answerbox);
  550. }
  551.  
  552. /** Answer an IPC call - fast version.
  553.  *
  554.  * This function can handle only two return arguments of payload, but is faster
  555.  * than the generic sys_ipc_answer().
  556.  *
  557.  * @param callid    Hash of the call to be answered.
  558.  * @param retval    Return value of the answer.
  559.  * @param arg1      Service-defined return value.
  560.  * @param arg2      Service-defined return value.
  561.  *
  562.  * @return      Return 0 on success, otherwise return an error code.   
  563.  */
  564. unative_t sys_ipc_answer_fast(unative_t callid, unative_t retval,
  565.     unative_t arg1, unative_t arg2)
  566. {
  567.     call_t *call;
  568.     ipc_data_t saved_data;
  569.     int saveddata = 0;
  570.     int rc;
  571.  
  572.     /* Do not answer notification callids */
  573.     if (callid & IPC_CALLID_NOTIFICATION)
  574.         return 0;
  575.  
  576.     call = get_call(callid);
  577.     if (!call)
  578.         return ENOENT;
  579.  
  580.     if (answer_need_old(call)) {
  581.         memcpy(&saved_data, &call->data, sizeof(call->data));
  582.         saveddata = 1;
  583.     }
  584.  
  585.     IPC_SET_RETVAL(call->data, retval);
  586.     IPC_SET_ARG1(call->data, arg1);
  587.     IPC_SET_ARG2(call->data, arg2);
  588.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  589.  
  590.     ipc_answer(&TASK->answerbox, call);
  591.     return rc;
  592. }
  593.  
  594. /** Answer an IPC call.
  595.  *
  596.  * @param callid    Hash of the call to be answered.
  597.  * @param data      Userspace address of call data with the answer.
  598.  *
  599.  * @return      Return 0 on success, otherwise return an error code.
  600.  */
  601. unative_t sys_ipc_answer(unative_t callid, ipc_data_t *data)
  602. {
  603.     call_t *call;
  604.     ipc_data_t saved_data;
  605.     int saveddata = 0;
  606.     int rc;
  607.  
  608.     /* Do not answer notification callids */
  609.     if (callid & IPC_CALLID_NOTIFICATION)
  610.         return 0;
  611.  
  612.     call = get_call(callid);
  613.     if (!call)
  614.         return ENOENT;
  615.  
  616.     if (answer_need_old(call)) {
  617.         memcpy(&saved_data, &call->data, sizeof(call->data));
  618.         saveddata = 1;
  619.     }
  620.     rc = copy_from_uspace(&call->data.args, &data->args,
  621.         sizeof(call->data.args));
  622.     if (rc != 0)
  623.         return rc;
  624.  
  625.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  626.    
  627.     ipc_answer(&TASK->answerbox, call);
  628.  
  629.     return rc;
  630. }
  631.  
  632. /** Hang up a phone.
  633.  *
  634.  * @param       Phone handle of the phone to be hung up.
  635.  *
  636.  * @return      Return 0 on success or an error code.
  637.  */
  638. unative_t sys_ipc_hangup(int phoneid)
  639. {
  640.     phone_t *phone;
  641.  
  642.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  643.  
  644.     if (ipc_phone_hangup(phone))
  645.         return -1;
  646.  
  647.     return 0;
  648. }
  649.  
  650. /** Wait for an incoming IPC call or an answer.
  651.  *
  652.  * @param calldata  Pointer to buffer where the call/answer data is stored.
  653.  * @param usec      Timeout. See waitq_sleep_timeout() for explanation.
  654.  * @param flags     Select mode of sleep operation. See waitq_sleep_timeout()
  655.  *          for explanation.
  656.  *
  657.  * @return      Hash of the call.
  658.  *          If IPC_CALLID_NOTIFICATION bit is set in the hash, the
  659.  *          call is a notification. IPC_CALLID_ANSWERED denotes an
  660.  *          answer.
  661.  */
  662. unative_t sys_ipc_wait_for_call(ipc_data_t *calldata, uint32_t usec, int flags)
  663. {
  664.     call_t *call;
  665.  
  666. restart:   
  667.     call = ipc_wait_for_call(&TASK->answerbox, usec,
  668.         flags | SYNCH_FLAGS_INTERRUPTIBLE);
  669.     if (!call)
  670.         return 0;
  671.  
  672.     if (call->flags & IPC_CALL_NOTIF) {
  673.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  674.  
  675.         /* Set in_phone_hash to the interrupt counter */
  676.         call->data.phone = (void *) call->priv;
  677.        
  678.         STRUCT_TO_USPACE(calldata, &call->data);
  679.  
  680.         ipc_call_free(call);
  681.        
  682.         return ((unative_t) call) | IPC_CALLID_NOTIFICATION;
  683.     }
  684.  
  685.     if (call->flags & IPC_CALL_ANSWERED) {
  686.         process_answer(call);
  687.  
  688.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  689.  
  690.         atomic_dec(&TASK->active_calls);
  691.  
  692.         if (call->flags & IPC_CALL_DISCARD_ANSWER) {
  693.             ipc_call_free(call);
  694.             goto restart;
  695.         }
  696.  
  697.         STRUCT_TO_USPACE(&calldata->args, &call->data.args);
  698.         ipc_call_free(call);
  699.  
  700.         return ((unative_t) call) | IPC_CALLID_ANSWERED;
  701.     }
  702.  
  703.     if (process_request(&TASK->answerbox, call))
  704.         goto restart;
  705.  
  706.     /* Include phone address('id') of the caller in the request,
  707.      * copy whole call->data, not only call->data.args */
  708.     if (STRUCT_TO_USPACE(calldata, &call->data)) {
  709.         return 0;
  710.     }
  711.     return (unative_t)call;
  712. }
  713.  
  714. /** Connect an IRQ handler to a task.
  715.  *
  716.  * @param inr       IRQ number.
  717.  * @param devno     Device number.
  718.  * @param method    Method to be associated with the notification.
  719.  * @param ucode     Uspace pointer to the top-half pseudocode.
  720.  *
  721.  * @return      EPERM or a return code returned by ipc_irq_register().
  722.  */
  723. unative_t sys_ipc_register_irq(inr_t inr, devno_t devno, unative_t method,
  724.     irq_code_t *ucode)
  725. {
  726.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  727.         return EPERM;
  728.  
  729.     return ipc_irq_register(&TASK->answerbox, inr, devno, method, ucode);
  730. }
  731.  
  732. /** Disconnect an IRQ handler from a task.
  733.  *
  734.  * @param inr       IRQ number.
  735.  * @param devno     Device number.
  736.  *
  737.  * @return      Zero on success or EPERM on error..
  738.  */
  739. unative_t sys_ipc_unregister_irq(inr_t inr, devno_t devno)
  740. {
  741.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  742.         return EPERM;
  743.  
  744.     ipc_irq_unregister(&TASK->answerbox, inr, devno);
  745.  
  746.     return 0;
  747. }
  748.  
  749. /** @}
  750.  */
  751.