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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 method_is_system(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 method_is_forwardable(unative_t method)
  90. {
  91.     switch (method) {
  92.     case IPC_M_PHONE_HUNGUP:
  93.         /* This message is meant only for the original recipient. */
  94.         return 0;
  95.     default:
  96.         return 1;
  97.     }
  98. }
  99.  
  100. /** Decide if the message with this method is immutable on forward.
  101.  *
  102.  * - some system messages may be forwarded, for some of them
  103.  *   it is useless
  104.  *
  105.  * @param method    Method to be decided.
  106.  *
  107.  * @return      Return 1 if the method is immutable on forward.
  108.  *          Otherwise return 0.
  109.  */
  110. static inline int method_is_immutable(unative_t method)
  111. {
  112.     switch (method) {
  113.     case IPC_M_AS_AREA_SEND:
  114.     case IPC_M_AS_AREA_RECV:
  115.     case IPC_M_DATA_SEND:
  116.         return 1;
  117.         break;
  118.     default:
  119.         return 0;
  120.     }
  121. }
  122.  
  123.  
  124. /***********************************************************************
  125.  * Functions that preprocess answer before sending it to the recepient.
  126.  ***********************************************************************/
  127.  
  128. /** Decide if the caller (e.g. ipc_answer()) should save the old call contents
  129.  * for answer_preprocess().
  130.  *
  131.  * @param call      Call structure to be decided.
  132.  *
  133.  * @return      Return 1 if the old call contents should be saved.
  134.  *          Return 0 otherwise.
  135.  */
  136. static inline int answer_need_old(call_t *call)
  137. {
  138.     switch (IPC_GET_METHOD(call->data)) {
  139.     case IPC_M_CONNECT_TO_ME:
  140.     case IPC_M_CONNECT_ME_TO:
  141.     case IPC_M_AS_AREA_SEND:
  142.     case IPC_M_AS_AREA_RECV:
  143.     case IPC_M_DATA_SEND:
  144.         return 1;
  145.     default:
  146.         return 0;
  147.     }
  148. }
  149.  
  150. /** Interpret process answer as control information.
  151.  *
  152.  * This function is called directly after sys_ipc_answer().
  153.  *
  154.  * @param answer    Call structure with the answer.
  155.  * @param olddata   Saved data of the request.
  156.  *
  157.  * @return      Return 0 on success or an error code.
  158.  */
  159. static inline int answer_preprocess(call_t *answer, ipc_data_t *olddata)
  160. {
  161.     int phoneid;
  162.  
  163.     if (IPC_GET_RETVAL(answer->data) == EHANGUP) {
  164.         /* In case of forward, hangup the forwared phone,
  165.          * not the originator
  166.          */
  167.         spinlock_lock(&answer->data.phone->lock);
  168.         spinlock_lock(&TASK->answerbox.lock);
  169.         if (answer->data.phone->state == IPC_PHONE_CONNECTED) {
  170.             list_remove(&answer->data.phone->link);
  171.             answer->data.phone->state = IPC_PHONE_SLAMMED;
  172.         }
  173.         spinlock_unlock(&TASK->answerbox.lock);
  174.         spinlock_unlock(&answer->data.phone->lock);
  175.     }
  176.  
  177.     if (!olddata)
  178.         return 0;
  179.  
  180.     if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_TO_ME) {
  181.         phoneid = IPC_GET_ARG3(*olddata);
  182.         if (IPC_GET_RETVAL(answer->data)) {
  183.             /* The connection was not accepted */
  184.             phone_dealloc(phoneid);
  185.         } else {
  186.             /* The connection was accepted */
  187.             phone_connect(phoneid, &answer->sender->answerbox);
  188.             /* Set 'phone hash' as arg3 of response */
  189.             IPC_SET_ARG3(answer->data,
  190.                 (unative_t) &TASK->phones[phoneid]);
  191.         }
  192.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME_TO) {
  193.         /* If the users accepted call, connect */
  194.         if (!IPC_GET_RETVAL(answer->data)) {
  195.             ipc_phone_connect((phone_t *) IPC_GET_ARG3(*olddata),
  196.                 &TASK->answerbox);
  197.         }
  198.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_AS_AREA_SEND) {
  199.         if (!IPC_GET_RETVAL(answer->data)) {
  200.             /* Accepted, handle as_area receipt */
  201.             ipl_t ipl;
  202.             int rc;
  203.             as_t *as;
  204.            
  205.             ipl = interrupts_disable();
  206.             spinlock_lock(&answer->sender->lock);
  207.             as = answer->sender->as;
  208.             spinlock_unlock(&answer->sender->lock);
  209.             interrupts_restore(ipl);
  210.            
  211.             rc = as_area_share(as, IPC_GET_ARG1(*olddata),
  212.                 IPC_GET_ARG2(*olddata), AS,
  213.                 IPC_GET_ARG1(answer->data), IPC_GET_ARG3(*olddata));
  214.             IPC_SET_RETVAL(answer->data, rc);
  215.             return rc;
  216.         }
  217.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_AS_AREA_RECV) {
  218.         if (!IPC_GET_RETVAL(answer->data)) {
  219.             ipl_t ipl;
  220.             as_t *as;
  221.             int rc;
  222.            
  223.             ipl = interrupts_disable();
  224.             spinlock_lock(&answer->sender->lock);
  225.             as = answer->sender->as;
  226.             spinlock_unlock(&answer->sender->lock);
  227.             interrupts_restore(ipl);
  228.            
  229.             rc = as_area_share(AS, IPC_GET_ARG1(answer->data),
  230.                 IPC_GET_ARG2(*olddata), as, IPC_GET_ARG1(*olddata),
  231.                 IPC_GET_ARG2(answer->data));
  232.             IPC_SET_RETVAL(answer->data, rc);
  233.         }
  234.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_DATA_SEND) {
  235.         if (!IPC_GET_RETVAL(answer->data)) {
  236.             int rc;
  237.             uintptr_t dst;
  238.             uintptr_t size;
  239.  
  240.             ASSERT(answer->buffer);
  241.  
  242.             dst = IPC_GET_ARG1(answer->data);
  243.             size = IPC_GET_ARG3(answer->data);
  244.  
  245.             rc = copy_to_uspace((void *) dst, answer->buffer, size);
  246.             if (rc != 0)
  247.                 IPC_SET_RETVAL(answer->data, rc);
  248.             free(answer->buffer);
  249.             answer->buffer = NULL;
  250.         }
  251.     }
  252.     return 0;
  253. }
  254.  
  255. /** Called before the request is sent.
  256.  *
  257.  * @param call      Call structure with the request.
  258.  *
  259.  * @return      Return 0 on success, ELIMIT or EPERM on error.
  260.  */
  261. static int request_preprocess(call_t *call)
  262. {
  263.     int newphid;
  264.     size_t size;
  265.     uintptr_t src;
  266.     int rc;
  267.  
  268.     switch (IPC_GET_METHOD(call->data)) {
  269.     case IPC_M_CONNECT_ME_TO:
  270.         newphid = phone_alloc();
  271.         if (newphid < 0)
  272.             return ELIMIT;
  273.         /* Set arg3 for server */
  274.         IPC_SET_ARG3(call->data, (unative_t) &TASK->phones[newphid]);
  275.         call->flags |= IPC_CALL_CONN_ME_TO;
  276.         call->priv = newphid;
  277.         break;
  278.     case IPC_M_AS_AREA_SEND:
  279.         size = as_area_get_size(IPC_GET_ARG1(call->data));
  280.         if (!size)
  281.             return EPERM;
  282.         IPC_SET_ARG2(call->data, size);
  283.         break;
  284.     case IPC_M_DATA_SEND:
  285.         src = IPC_GET_ARG2(call->data);
  286.         size = IPC_GET_ARG3(call->data);
  287.        
  288.         if ((size <= 0) || (size > DATA_SEND_LIMIT))
  289.             return ELIMIT;
  290.        
  291.         call->buffer = (uint8_t *) malloc(size, 0);
  292.         rc = copy_from_uspace(call->buffer, (void *) src, size);
  293.         if (rc != 0) {
  294.             free(call->buffer);
  295.             return rc;
  296.         }
  297.         break;
  298.     default:
  299.         break;
  300.     }
  301.     return 0;
  302. }
  303.  
  304. /*******************************************************************************
  305.  * Functions called to process received call/answer before passing it to uspace.
  306.  *******************************************************************************/
  307.  
  308. /** Do basic kernel processing of received call answer.
  309.  *
  310.  * @param call      Call structure with the answer.
  311.  */
  312. static void process_answer(call_t *call)
  313. {
  314.     if (IPC_GET_RETVAL(call->data) == EHANGUP &&
  315.         (call->flags & IPC_CALL_FORWARDED))
  316.         IPC_SET_RETVAL(call->data, EFORWARD);
  317.  
  318.     if (call->flags & IPC_CALL_CONN_ME_TO) {
  319.         if (IPC_GET_RETVAL(call->data))
  320.             phone_dealloc(call->priv);
  321.         else
  322.             IPC_SET_ARG3(call->data, call->priv);
  323.     }
  324. }
  325.  
  326. /** Do basic kernel processing of received call request.
  327.  *
  328.  * @param box       Destination answerbox structure.
  329.  * @param call      Call structure with the request.
  330.  *
  331.  * @return      Return 0 if the call should be passed to userspace.
  332.  *          Return -1 if the call should be ignored.
  333.  */
  334. static int process_request(answerbox_t *box, call_t *call)
  335. {
  336.     int phoneid;
  337.  
  338.     if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME) {
  339.         phoneid = phone_alloc();
  340.         if (phoneid < 0) { /* Failed to allocate phone */
  341.             IPC_SET_RETVAL(call->data, ELIMIT);
  342.             ipc_answer(box, call);
  343.             return -1;
  344.         }
  345.         IPC_SET_ARG3(call->data, phoneid);
  346.     }
  347.     return 0;
  348. }
  349.  
  350. /** Make a fast call over IPC, wait for reply and return to user.
  351.  *
  352.  * This function can handle only one argument of payload, but is faster than
  353.  * the generic function (i.e. sys_ipc_call_sync()).
  354.  *
  355.  * @param phoneid   Phone handle for the call.
  356.  * @param method    Method of the call.
  357.  * @param arg1      Service-defined payload argument.
  358.  * @param data      Address of userspace structure where the reply call will
  359.  *          be stored.
  360.  *
  361.  * @return      Returns 0 on success.
  362.  *          Return ENOENT if there is no such phone handle.
  363.  */
  364. unative_t sys_ipc_call_sync_fast(unative_t phoneid, unative_t method,
  365.     unative_t arg1, ipc_data_t *data)
  366. {
  367.     call_t call;
  368.     phone_t *phone;
  369.     int res;
  370.  
  371.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  372.  
  373.     ipc_call_static_init(&call);
  374.     IPC_SET_METHOD(call.data, method);
  375.     IPC_SET_ARG1(call.data, arg1);
  376.  
  377.     if (!(res = request_preprocess(&call))) {
  378.         ipc_call_sync(phone, &call);
  379.         process_answer(&call);
  380.     } else {
  381.         IPC_SET_RETVAL(call.data, res);
  382.     }
  383.     STRUCT_TO_USPACE(&data->args, &call.data.args);
  384.  
  385.     return 0;
  386. }
  387.  
  388. /** Make a synchronous IPC call allowing to transmit the entire payload.
  389.  *
  390.  * @param phoneid   Phone handle for the call.
  391.  * @param question  Userspace address of call data with the request.
  392.  * @param reply     Userspace address of call data where to store the
  393.  *          answer.
  394.  *
  395.  * @return      Zero on success or an error code.
  396.  */
  397. unative_t sys_ipc_call_sync(unative_t phoneid, ipc_data_t *question,
  398.     ipc_data_t *reply)
  399. {
  400.     call_t call;
  401.     phone_t *phone;
  402.     int res;
  403.     int rc;
  404.  
  405.     ipc_call_static_init(&call);
  406.     rc = copy_from_uspace(&call.data.args, &question->args,
  407.         sizeof(call.data.args));
  408.     if (rc != 0)
  409.         return (unative_t) rc;
  410.  
  411.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  412.  
  413.     if (!(res = request_preprocess(&call))) {
  414.         ipc_call_sync(phone, &call);
  415.         process_answer(&call);
  416.     } else
  417.         IPC_SET_RETVAL(call.data, res);
  418.  
  419.     rc = STRUCT_TO_USPACE(&reply->args, &call.data.args);
  420.     if (rc != 0)
  421.         return rc;
  422.  
  423.     return 0;
  424. }
  425.  
  426. /** Check that the task did not exceed the allowed limit of asynchronous calls.
  427.  *
  428.  * @return      Return 0 if limit not reached or -1 if limit exceeded.
  429.  */
  430. static int check_call_limit(void)
  431. {
  432.     if (atomic_preinc(&TASK->active_calls) > IPC_MAX_ASYNC_CALLS) {
  433.         atomic_dec(&TASK->active_calls);
  434.         return -1;
  435.     }
  436.     return 0;
  437. }
  438.  
  439. /** Make a fast asynchronous call over IPC.
  440.  *
  441.  * This function can only handle two arguments of payload, but is faster than
  442.  * the generic function sys_ipc_call_async().
  443.  *
  444.  * @param phoneid   Phone handle for the call.
  445.  * @param method    Method of the call.
  446.  * @param arg1      Service-defined payload argument.
  447.  * @param arg2      Service-defined payload argument.
  448.  *
  449.  * @return      Return call hash on success.
  450.  *          Return IPC_CALLRET_FATAL in case of a fatal error and
  451.  *          IPC_CALLRET_TEMPORARY if there are too many pending
  452.  *          asynchronous requests; answers should be handled first.
  453.  */
  454. unative_t sys_ipc_call_async_fast(unative_t phoneid, unative_t method,
  455.     unative_t arg1, unative_t arg2)
  456. {
  457.     call_t *call;
  458.     phone_t *phone;
  459.     int res;
  460.  
  461.     if (check_call_limit())
  462.         return IPC_CALLRET_TEMPORARY;
  463.  
  464.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  465.  
  466.     call = ipc_call_alloc(0);
  467.     IPC_SET_METHOD(call->data, method);
  468.     IPC_SET_ARG1(call->data, arg1);
  469.     IPC_SET_ARG2(call->data, arg2);
  470.     IPC_SET_ARG3(call->data, 0);
  471.  
  472.     if (!(res = request_preprocess(call)))
  473.         ipc_call(phone, call);
  474.     else
  475.         ipc_backsend_err(phone, call, res);
  476.  
  477.     return (unative_t) call;
  478. }
  479.  
  480. /** Make an asynchronous IPC call allowing to transmit the entire payload.
  481.  *
  482.  * @param phoneid   Phone handle for the call.
  483.  * @param data      Userspace address of call data with the request.
  484.  *
  485.  * @return      See sys_ipc_call_async_fast().
  486.  */
  487. unative_t sys_ipc_call_async(unative_t phoneid, ipc_data_t *data)
  488. {
  489.     call_t *call;
  490.     phone_t *phone;
  491.     int res;
  492.     int rc;
  493.  
  494.     if (check_call_limit())
  495.         return IPC_CALLRET_TEMPORARY;
  496.  
  497.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  498.  
  499.     call = ipc_call_alloc(0);
  500.     rc = copy_from_uspace(&call->data.args, &data->args,
  501.         sizeof(call->data.args));
  502.     if (rc != 0) {
  503.         ipc_call_free(call);
  504.         return (unative_t) rc;
  505.     }
  506.     if (!(res = request_preprocess(call)))
  507.         ipc_call(phone, call);
  508.     else
  509.         ipc_backsend_err(phone, call, res);
  510.  
  511.     return (unative_t) call;
  512. }
  513.  
  514. /** Forward a received call to another destination.
  515.  *
  516.  * @param callid    Hash of the call to forward.
  517.  * @param phoneid   Phone handle to use for forwarding.
  518.  * @param method    New method to use for the forwarded call.
  519.  * @param arg1      New value of the first argument for the forwarded call.
  520.  *
  521.  * @return      Return 0 on succes, otherwise return an error code.
  522.  *
  523.  * In case the original method is a system method, ARG1 and ARG2 are overwritten
  524.  * in the forwarded message with the new method and the new arg1, respectively.
  525.  * Otherwise the METHOD and ARG1 are rewritten with the new method and arg1,
  526.  * respectively. Also note there is a set of immutable methods, for which the
  527.  * new method and argument is not set and these values are ignored.
  528.  *
  529.  * Warning: If implementing non-fast version, make sure that
  530.  *          ARG3 is not rewritten for certain system IPC
  531.  */
  532. unative_t sys_ipc_forward_fast(unative_t callid, unative_t phoneid,
  533.     unative_t method, unative_t arg1)
  534. {
  535.     call_t *call;
  536.     phone_t *phone;
  537.  
  538.     call = get_call(callid);
  539.     if (!call)
  540.         return ENOENT;
  541.  
  542.     call->flags |= IPC_CALL_FORWARDED;
  543.  
  544.     GET_CHECK_PHONE(phone, phoneid, {
  545.         IPC_SET_RETVAL(call->data, EFORWARD);
  546.         ipc_answer(&TASK->answerbox, call);
  547.         return ENOENT;
  548.     });    
  549.  
  550.     if (!method_is_forwardable(IPC_GET_METHOD(call->data))) {
  551.         IPC_SET_RETVAL(call->data, EFORWARD);
  552.         ipc_answer(&TASK->answerbox, call);
  553.         return EPERM;
  554.     }
  555.  
  556.     /*
  557.      * Userspace is not allowed to change method of system methods on
  558.      * forward, allow changing ARG1 and ARG2 by means of method and arg1.
  559.      * If the method is immutable, don't change anything.
  560.      */
  561.     if (!method_is_immutable(IPC_GET_METHOD(call->data))) {
  562.         if (method_is_system(IPC_GET_METHOD(call->data))) {
  563.             if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME)
  564.                 phone_dealloc(IPC_GET_ARG3(call->data));
  565.  
  566.             IPC_SET_ARG1(call->data, method);
  567.             IPC_SET_ARG2(call->data, arg1);
  568.         } else {
  569.             IPC_SET_METHOD(call->data, method);
  570.             IPC_SET_ARG1(call->data, arg1);
  571.         }
  572.     }
  573.  
  574.     return ipc_forward(call, phone, &TASK->answerbox);
  575. }
  576.  
  577. /** Answer an IPC call - fast version.
  578.  *
  579.  * This function can handle only two return arguments of payload, but is faster
  580.  * than the generic sys_ipc_answer().
  581.  *
  582.  * @param callid    Hash of the call to be answered.
  583.  * @param retval    Return value of the answer.
  584.  * @param arg1      Service-defined return value.
  585.  * @param arg2      Service-defined return value.
  586.  *
  587.  * @return      Return 0 on success, otherwise return an error code.   
  588.  */
  589. unative_t sys_ipc_answer_fast(unative_t callid, unative_t retval,
  590.     unative_t arg1, unative_t arg2)
  591. {
  592.     call_t *call;
  593.     ipc_data_t saved_data;
  594.     int saveddata = 0;
  595.     int rc;
  596.  
  597.     /* Do not answer notification callids */
  598.     if (callid & IPC_CALLID_NOTIFICATION)
  599.         return 0;
  600.  
  601.     call = get_call(callid);
  602.     if (!call)
  603.         return ENOENT;
  604.  
  605.     if (answer_need_old(call)) {
  606.         memcpy(&saved_data, &call->data, sizeof(call->data));
  607.         saveddata = 1;
  608.     }
  609.  
  610.     IPC_SET_RETVAL(call->data, retval);
  611.     IPC_SET_ARG1(call->data, arg1);
  612.     IPC_SET_ARG2(call->data, arg2);
  613.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  614.  
  615.     ipc_answer(&TASK->answerbox, call);
  616.     return rc;
  617. }
  618.  
  619. /** Answer an IPC call.
  620.  *
  621.  * @param callid    Hash of the call to be answered.
  622.  * @param data      Userspace address of call data with the answer.
  623.  *
  624.  * @return      Return 0 on success, otherwise return an error code.
  625.  */
  626. unative_t sys_ipc_answer(unative_t callid, ipc_data_t *data)
  627. {
  628.     call_t *call;
  629.     ipc_data_t saved_data;
  630.     int saveddata = 0;
  631.     int rc;
  632.  
  633.     /* Do not answer notification callids */
  634.     if (callid & IPC_CALLID_NOTIFICATION)
  635.         return 0;
  636.  
  637.     call = get_call(callid);
  638.     if (!call)
  639.         return ENOENT;
  640.  
  641.     if (answer_need_old(call)) {
  642.         memcpy(&saved_data, &call->data, sizeof(call->data));
  643.         saveddata = 1;
  644.     }
  645.     rc = copy_from_uspace(&call->data.args, &data->args,
  646.         sizeof(call->data.args));
  647.     if (rc != 0)
  648.         return rc;
  649.  
  650.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  651.    
  652.     ipc_answer(&TASK->answerbox, call);
  653.  
  654.     return rc;
  655. }
  656.  
  657. /** Hang up a phone.
  658.  *
  659.  * @param       Phone handle of the phone to be hung up.
  660.  *
  661.  * @return      Return 0 on success or an error code.
  662.  */
  663. unative_t sys_ipc_hangup(int phoneid)
  664. {
  665.     phone_t *phone;
  666.  
  667.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  668.  
  669.     if (ipc_phone_hangup(phone))
  670.         return -1;
  671.  
  672.     return 0;
  673. }
  674.  
  675. /** Wait for an incoming IPC call or an answer.
  676.  *
  677.  * @param calldata  Pointer to buffer where the call/answer data is stored.
  678.  * @param usec      Timeout. See waitq_sleep_timeout() for explanation.
  679.  * @param flags     Select mode of sleep operation. See waitq_sleep_timeout()
  680.  *          for explanation.
  681.  *
  682.  * @return      Hash of the call.
  683.  *          If IPC_CALLID_NOTIFICATION bit is set in the hash, the
  684.  *          call is a notification. IPC_CALLID_ANSWERED denotes an
  685.  *          answer.
  686.  */
  687. unative_t sys_ipc_wait_for_call(ipc_data_t *calldata, uint32_t usec, int flags)
  688. {
  689.     call_t *call;
  690.  
  691. restart:   
  692.     call = ipc_wait_for_call(&TASK->answerbox, usec,
  693.         flags | SYNCH_FLAGS_INTERRUPTIBLE);
  694.     if (!call)
  695.         return 0;
  696.  
  697.     if (call->flags & IPC_CALL_NOTIF) {
  698.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  699.  
  700.         /* Set in_phone_hash to the interrupt counter */
  701.         call->data.phone = (void *) call->priv;
  702.        
  703.         STRUCT_TO_USPACE(calldata, &call->data);
  704.  
  705.         ipc_call_free(call);
  706.        
  707.         return ((unative_t) call) | IPC_CALLID_NOTIFICATION;
  708.     }
  709.  
  710.     if (call->flags & IPC_CALL_ANSWERED) {
  711.         process_answer(call);
  712.  
  713.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  714.  
  715.         atomic_dec(&TASK->active_calls);
  716.  
  717.         if (call->flags & IPC_CALL_DISCARD_ANSWER) {
  718.             ipc_call_free(call);
  719.             goto restart;
  720.         }
  721.  
  722.         STRUCT_TO_USPACE(&calldata->args, &call->data.args);
  723.         ipc_call_free(call);
  724.  
  725.         return ((unative_t) call) | IPC_CALLID_ANSWERED;
  726.     }
  727.  
  728.     if (process_request(&TASK->answerbox, call))
  729.         goto restart;
  730.  
  731.     /* Include phone address('id') of the caller in the request,
  732.      * copy whole call->data, not only call->data.args */
  733.     if (STRUCT_TO_USPACE(calldata, &call->data)) {
  734.         return 0;
  735.     }
  736.     return (unative_t)call;
  737. }
  738.  
  739. /** Connect an IRQ handler to a task.
  740.  *
  741.  * @param inr       IRQ number.
  742.  * @param devno     Device number.
  743.  * @param method    Method to be associated with the notification.
  744.  * @param ucode     Uspace pointer to the top-half pseudocode.
  745.  *
  746.  * @return      EPERM or a return code returned by ipc_irq_register().
  747.  */
  748. unative_t sys_ipc_register_irq(inr_t inr, devno_t devno, unative_t method,
  749.     irq_code_t *ucode)
  750. {
  751.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  752.         return EPERM;
  753.  
  754.     return ipc_irq_register(&TASK->answerbox, inr, devno, method, ucode);
  755. }
  756.  
  757. /** Disconnect an IRQ handler from a task.
  758.  *
  759.  * @param inr       IRQ number.
  760.  * @param devno     Device number.
  761.  *
  762.  * @return      Zero on success or EPERM on error..
  763.  */
  764. unative_t sys_ipc_unregister_irq(inr_t inr, devno_t devno)
  765. {
  766.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  767.         return EPERM;
  768.  
  769.     ipc_irq_unregister(&TASK->answerbox, inr, devno);
  770.  
  771.     return 0;
  772. }
  773.  
  774. /** @}
  775.  */
  776.