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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_CONNECTION_CLONE:
  97.     case IPC_M_CONNECT_ME:
  98.     case IPC_M_PHONE_HUNGUP:
  99.         /* This message is meant only for the original recipient. */
  100.         return 0;
  101.     default:
  102.         return 1;
  103.     }
  104. }
  105.  
  106. /** Decide if the message with this method is immutable on forward.
  107.  *
  108.  * - some system messages may be forwarded but their content cannot be altered
  109.  *
  110.  * @param method    Method to be decided.
  111.  *
  112.  * @return      Return 1 if the method is immutable on forward.
  113.  *          Otherwise return 0.
  114.  */
  115. static inline int method_is_immutable(unative_t method)
  116. {
  117.     switch (method) {
  118.     case IPC_M_SHARE_OUT:
  119.     case IPC_M_SHARE_IN:
  120.     case IPC_M_DATA_WRITE:
  121.     case IPC_M_DATA_READ:
  122.         return 1;
  123.         break;
  124.     default:
  125.         return 0;
  126.     }
  127. }
  128.  
  129.  
  130. /***********************************************************************
  131.  * Functions that preprocess answer before sending it to the recepient.
  132.  ***********************************************************************/
  133.  
  134. /** Decide if the caller (e.g. ipc_answer()) should save the old call contents
  135.  * for answer_preprocess().
  136.  *
  137.  * @param call      Call structure to be decided.
  138.  *
  139.  * @return      Return 1 if the old call contents should be saved.
  140.  *          Return 0 otherwise.
  141.  */
  142. static inline int answer_need_old(call_t *call)
  143. {
  144.     switch (IPC_GET_METHOD(call->data)) {
  145.     case IPC_M_CONNECTION_CLONE:
  146.     case IPC_M_CONNECT_ME:
  147.     case IPC_M_CONNECT_TO_ME:
  148.     case IPC_M_CONNECT_ME_TO:
  149.     case IPC_M_SHARE_OUT:
  150.     case IPC_M_SHARE_IN:
  151.     case IPC_M_DATA_WRITE:
  152.     case IPC_M_DATA_READ:
  153.         return 1;
  154.     default:
  155.         return 0;
  156.     }
  157. }
  158.  
  159. /** Interpret process answer as control information.
  160.  *
  161.  * This function is called directly after sys_ipc_answer().
  162.  *
  163.  * @param answer    Call structure with the answer.
  164.  * @param olddata   Saved data of the request.
  165.  *
  166.  * @return      Return 0 on success or an error code.
  167.  */
  168. static inline int answer_preprocess(call_t *answer, ipc_data_t *olddata)
  169. {
  170.     int phoneid;
  171.  
  172.     if ((native_t) IPC_GET_RETVAL(answer->data) == EHANGUP) {
  173.         /* In case of forward, hangup the forwared phone,
  174.          * not the originator
  175.          */
  176.         mutex_lock(&answer->data.phone->lock);
  177.         spinlock_lock(&TASK->answerbox.lock);
  178.         if (answer->data.phone->state == IPC_PHONE_CONNECTED) {
  179.             list_remove(&answer->data.phone->link);
  180.             answer->data.phone->state = IPC_PHONE_SLAMMED;
  181.         }
  182.         spinlock_unlock(&TASK->answerbox.lock);
  183.         mutex_unlock(&answer->data.phone->lock);
  184.     }
  185.  
  186.     if (!olddata)
  187.         return 0;
  188.  
  189.     if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECTION_CLONE) {
  190.         phoneid = IPC_GET_ARG1(*olddata);
  191.         phone_t *phone = &TASK->phones[phoneid];
  192.         if (IPC_GET_RETVAL(answer->data) != EOK) {
  193.             /*
  194.              * The recipient of the cloned phone rejected the offer.
  195.              * In this case, the connection was established at the
  196.              * request time and therefore we need to slam the phone.
  197.              * We don't merely hangup as that would result in
  198.              * sending IPC_M_HUNGUP to the third party on the
  199.              * other side of the cloned phone.
  200.              */
  201.             mutex_lock(&phone->lock);
  202.             if (phone->state == IPC_PHONE_CONNECTED) {
  203.                 spinlock_lock(&phone->callee->lock);
  204.                 list_remove(&phone->link);
  205.                 phone->state = IPC_PHONE_SLAMMED;
  206.                 spinlock_unlock(&phone->callee->lock);
  207.             }
  208.             mutex_unlock(&phone->lock);
  209.         }
  210.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME) {
  211.         phone_t *phone = (phone_t *)IPC_GET_ARG5(*olddata);
  212.         if (IPC_GET_RETVAL(answer->data) != EOK) {
  213.             /*
  214.              * The other party on the cloned phoned rejected our
  215.              * request for connection on the protocol level.
  216.              * We need to break the connection without sending
  217.              * IPC_M_HUNGUP back.
  218.              */
  219.             mutex_lock(&phone->lock);
  220.             if (phone->state == IPC_PHONE_CONNECTED) {
  221.                 spinlock_lock(&phone->callee->lock);
  222.                 list_remove(&phone->link);
  223.                 phone->state = IPC_PHONE_SLAMMED;
  224.                 spinlock_unlock(&phone->callee->lock);
  225.             }
  226.             mutex_unlock(&phone->lock);
  227.         }
  228.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_TO_ME) {
  229.         phoneid = IPC_GET_ARG5(*olddata);
  230.         if (IPC_GET_RETVAL(answer->data) != EOK) {
  231.             /* The connection was not accepted */
  232.             phone_dealloc(phoneid);
  233.         } else {
  234.             /* The connection was accepted */
  235.             phone_connect(phoneid, &answer->sender->answerbox);
  236.             /* Set 'phone hash' as arg5 of response */
  237.             IPC_SET_ARG5(answer->data,
  238.                 (unative_t) &TASK->phones[phoneid]);
  239.         }
  240.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_CONNECT_ME_TO) {
  241.         /* If the users accepted call, connect */
  242.         if (IPC_GET_RETVAL(answer->data) == EOK) {
  243.             ipc_phone_connect((phone_t *) IPC_GET_ARG5(*olddata),
  244.                 &TASK->answerbox);
  245.         }
  246.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_SHARE_OUT) {
  247.         if (!IPC_GET_RETVAL(answer->data)) {
  248.             /* Accepted, handle as_area receipt */
  249.             ipl_t ipl;
  250.             int rc;
  251.             as_t *as;
  252.            
  253.             ipl = interrupts_disable();
  254.             spinlock_lock(&answer->sender->lock);
  255.             as = answer->sender->as;
  256.             spinlock_unlock(&answer->sender->lock);
  257.             interrupts_restore(ipl);
  258.            
  259.             rc = as_area_share(as, IPC_GET_ARG1(*olddata),
  260.                 IPC_GET_ARG2(*olddata), AS,
  261.                 IPC_GET_ARG1(answer->data), IPC_GET_ARG3(*olddata));
  262.             IPC_SET_RETVAL(answer->data, rc);
  263.             return rc;
  264.         }
  265.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_SHARE_IN) {
  266.         if (!IPC_GET_RETVAL(answer->data)) {
  267.             ipl_t ipl;
  268.             as_t *as;
  269.             int rc;
  270.            
  271.             ipl = interrupts_disable();
  272.             spinlock_lock(&answer->sender->lock);
  273.             as = answer->sender->as;
  274.             spinlock_unlock(&answer->sender->lock);
  275.             interrupts_restore(ipl);
  276.            
  277.             rc = as_area_share(AS, IPC_GET_ARG1(answer->data),
  278.                 IPC_GET_ARG2(*olddata), as, IPC_GET_ARG1(*olddata),
  279.                 IPC_GET_ARG2(answer->data));
  280.             IPC_SET_RETVAL(answer->data, rc);
  281.         }
  282.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_DATA_READ) {
  283.         ASSERT(!answer->buffer);
  284.         if (!IPC_GET_RETVAL(answer->data)) {
  285.             /* The recipient agreed to send data. */
  286.             uintptr_t src = IPC_GET_ARG1(answer->data);
  287.             uintptr_t dst = IPC_GET_ARG1(*olddata);
  288.             size_t max_size = IPC_GET_ARG2(*olddata);
  289.             size_t size = IPC_GET_ARG2(answer->data);
  290.             if (size && size <= max_size) {
  291.                 /*
  292.                  * Copy the destination VA so that this piece of
  293.                  * information is not lost.
  294.                  */
  295.                 IPC_SET_ARG1(answer->data, dst);
  296.  
  297.                 answer->buffer = malloc(size, 0);
  298.                 int rc = copy_from_uspace(answer->buffer,
  299.                     (void *) src, size);
  300.                 if (rc) {
  301.                     IPC_SET_RETVAL(answer->data, rc);
  302.                     free(answer->buffer);
  303.                     answer->buffer = NULL;
  304.                 }
  305.             } else if (!size) {
  306.                 IPC_SET_RETVAL(answer->data, EOK);
  307.             } else {
  308.                 IPC_SET_RETVAL(answer->data, ELIMIT);
  309.             }
  310.         }
  311.     } else if (IPC_GET_METHOD(*olddata) == IPC_M_DATA_WRITE) {
  312.         ASSERT(answer->buffer);
  313.         if (!IPC_GET_RETVAL(answer->data)) {
  314.             /* The recipient agreed to receive data. */
  315.             int rc;
  316.             uintptr_t dst;
  317.             size_t size;
  318.             size_t max_size;
  319.  
  320.             dst = (uintptr_t)IPC_GET_ARG1(answer->data);
  321.             size = (size_t)IPC_GET_ARG2(answer->data);
  322.             max_size = (size_t)IPC_GET_ARG2(*olddata);
  323.  
  324.             if (size <= max_size) {
  325.                 rc = copy_to_uspace((void *) dst,
  326.                     answer->buffer, size);
  327.                 if (rc)
  328.                     IPC_SET_RETVAL(answer->data, rc);
  329.             } else {
  330.                 IPC_SET_RETVAL(answer->data, ELIMIT);
  331.             }
  332.         }
  333.         free(answer->buffer);
  334.         answer->buffer = NULL;
  335.     }
  336.     return 0;
  337. }
  338.  
  339. static void phones_lock(phone_t *p1, phone_t *p2)
  340. {
  341.     if (p1 < p2) {
  342.         mutex_lock(&p1->lock);
  343.         mutex_lock(&p2->lock);
  344.     } else if (p1 > p2) {
  345.         mutex_lock(&p2->lock);
  346.         mutex_lock(&p1->lock);
  347.     } else {
  348.         mutex_lock(&p1->lock);
  349.     }
  350. }
  351.  
  352. static void phones_unlock(phone_t *p1, phone_t *p2)
  353. {
  354.     mutex_unlock(&p1->lock);
  355.     if (p1 != p2)
  356.         mutex_unlock(&p2->lock);
  357. }
  358.  
  359. /** Called before the request is sent.
  360.  *
  361.  * @param call      Call structure with the request.
  362.  * @param phone     Phone that the call will be sent through.
  363.  *
  364.  * @return      Return 0 on success, ELIMIT or EPERM on error.
  365.  */
  366. static int request_preprocess(call_t *call, phone_t *phone)
  367. {
  368.     int newphid;
  369.     size_t size;
  370.     uintptr_t src;
  371.     int rc;
  372.  
  373.     switch (IPC_GET_METHOD(call->data)) {
  374.     case IPC_M_CONNECTION_CLONE: {
  375.         phone_t *cloned_phone;
  376.         GET_CHECK_PHONE(cloned_phone, IPC_GET_ARG1(call->data),
  377.             return ENOENT);
  378.         phones_lock(cloned_phone, phone);
  379.         if ((cloned_phone->state != IPC_PHONE_CONNECTED) ||
  380.             phone->state != IPC_PHONE_CONNECTED) {
  381.             phones_unlock(cloned_phone, phone);
  382.             return EINVAL;
  383.         }
  384.         /*
  385.          * We can be pretty sure now that both tasks exist and we are
  386.          * connected to them. As we continue to hold the phone locks,
  387.          * we are effectively preventing them from finishing their
  388.          * potential cleanup.
  389.          */
  390.         newphid = phone_alloc(phone->callee->task);
  391.         if (newphid < 0) {
  392.             phones_unlock(cloned_phone, phone);
  393.             return ELIMIT;
  394.         }
  395.         ipc_phone_connect(&phone->callee->task->phones[newphid],
  396.             cloned_phone->callee);
  397.         phones_unlock(cloned_phone, phone);
  398.         /* Set the new phone for the callee. */
  399.         IPC_SET_ARG1(call->data, newphid);
  400.         break;
  401.     }
  402.     case IPC_M_CONNECT_ME:
  403.         IPC_SET_ARG5(call->data, (unative_t) phone);
  404.         break;
  405.     case IPC_M_CONNECT_ME_TO:
  406.         newphid = phone_alloc(TASK);
  407.         if (newphid < 0)
  408.             return ELIMIT;
  409.         /* Set arg5 for server */
  410.         IPC_SET_ARG5(call->data, (unative_t) &TASK->phones[newphid]);
  411.         call->flags |= IPC_CALL_CONN_ME_TO;
  412.         call->priv = newphid;
  413.         break;
  414.     case IPC_M_SHARE_OUT:
  415.         size = as_area_get_size(IPC_GET_ARG1(call->data));
  416.         if (!size)
  417.             return EPERM;
  418.         IPC_SET_ARG2(call->data, size);
  419.         break;
  420.     case IPC_M_DATA_READ:
  421.         size = IPC_GET_ARG2(call->data);
  422.         if ((size <= 0 || (size > DATA_XFER_LIMIT)))
  423.             return ELIMIT;
  424.         break;
  425.     case IPC_M_DATA_WRITE:
  426.         src = IPC_GET_ARG1(call->data);
  427.         size = IPC_GET_ARG2(call->data);
  428.        
  429.         if (size > DATA_XFER_LIMIT)
  430.             return ELIMIT;
  431.        
  432.         call->buffer = (uint8_t *) malloc(size, 0);
  433.         rc = copy_from_uspace(call->buffer, (void *) src, size);
  434.         if (rc != 0) {
  435.             free(call->buffer);
  436.             return rc;
  437.         }
  438.         break;
  439. #ifdef CONFIG_UDEBUG
  440.     case IPC_M_DEBUG_ALL:
  441.         return udebug_request_preprocess(call, phone);
  442. #endif
  443.     default:
  444.         break;
  445.     }
  446.     return 0;
  447. }
  448.  
  449. /*******************************************************************************
  450.  * Functions called to process received call/answer before passing it to uspace.
  451.  *******************************************************************************/
  452.  
  453. /** Do basic kernel processing of received call answer.
  454.  *
  455.  * @param call      Call structure with the answer.
  456.  */
  457. static void process_answer(call_t *call)
  458. {
  459.     if (((native_t) IPC_GET_RETVAL(call->data) == EHANGUP) &&
  460.         (call->flags & IPC_CALL_FORWARDED))
  461.         IPC_SET_RETVAL(call->data, EFORWARD);
  462.  
  463.     if (call->flags & IPC_CALL_CONN_ME_TO) {
  464.         if (IPC_GET_RETVAL(call->data))
  465.             phone_dealloc(call->priv);
  466.         else
  467.             IPC_SET_ARG5(call->data, call->priv);
  468.     }
  469.  
  470.     if (call->buffer) {
  471.         /* This must be an affirmative answer to IPC_M_DATA_READ. */
  472.         /* or IPC_M_DEBUG_ALL/UDEBUG_M_MEM_READ... */
  473.         uintptr_t dst = IPC_GET_ARG1(call->data);
  474.         size_t size = IPC_GET_ARG2(call->data);
  475.         int rc = copy_to_uspace((void *) dst, call->buffer, size);
  476.         if (rc)
  477.             IPC_SET_RETVAL(call->data, rc);
  478.         free(call->buffer);
  479.         call->buffer = NULL;
  480.     }
  481. }
  482.  
  483. /** Do basic kernel processing of received call request.
  484.  *
  485.  * @param box       Destination answerbox structure.
  486.  * @param call      Call structure with the request.
  487.  *
  488.  * @return      Return 0 if the call should be passed to userspace.
  489.  *          Return -1 if the call should be ignored.
  490.  */
  491. static int process_request(answerbox_t *box, call_t *call)
  492. {
  493.     int phoneid;
  494.  
  495.     if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME) {
  496.         phoneid = phone_alloc(TASK);
  497.         if (phoneid < 0) { /* Failed to allocate phone */
  498.             IPC_SET_RETVAL(call->data, ELIMIT);
  499.             ipc_answer(box, call);
  500.             return -1;
  501.         }
  502.         IPC_SET_ARG5(call->data, phoneid);
  503.     }
  504.     switch (IPC_GET_METHOD(call->data)) {
  505.     case IPC_M_DEBUG_ALL:
  506.         return -1;
  507.     default:
  508.         break;
  509.     }
  510.     return 0;
  511. }
  512.  
  513. /** Make a fast call over IPC, wait for reply and return to user.
  514.  *
  515.  * This function can handle only three arguments of payload, but is faster than
  516.  * the generic function (i.e. sys_ipc_call_sync_slow()).
  517.  *
  518.  * @param phoneid   Phone handle for the call.
  519.  * @param method    Method of the call.
  520.  * @param arg1      Service-defined payload argument.
  521.  * @param arg2      Service-defined payload argument.
  522.  * @param arg3      Service-defined payload argument.
  523.  * @param data      Address of userspace structure where the reply call will
  524.  *          be stored.
  525.  *
  526.  * @return      Returns 0 on success.
  527.  *          Return ENOENT if there is no such phone handle.
  528.  */
  529. unative_t sys_ipc_call_sync_fast(unative_t phoneid, unative_t method,
  530.     unative_t arg1, unative_t arg2, unative_t arg3, ipc_data_t *data)
  531. {
  532.     call_t call;
  533.     phone_t *phone;
  534.     int res;
  535.     int rc;
  536.    
  537.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  538.  
  539.     ipc_call_static_init(&call);
  540.     IPC_SET_METHOD(call.data, method);
  541.     IPC_SET_ARG1(call.data, arg1);
  542.     IPC_SET_ARG2(call.data, arg2);
  543.     IPC_SET_ARG3(call.data, arg3);
  544.     /*
  545.      * To achieve deterministic behavior, zero out arguments that are beyond
  546.      * the limits of the fast version.
  547.      */
  548.     IPC_SET_ARG4(call.data, 0);
  549.     IPC_SET_ARG5(call.data, 0);
  550.  
  551.     if (!(res = request_preprocess(&call, phone))) {
  552. #ifdef CONFIG_UDEBUG
  553.         udebug_stoppable_begin();
  554. #endif
  555.         rc = ipc_call_sync(phone, &call);
  556. #ifdef CONFIG_UDEBUG
  557.         udebug_stoppable_end();
  558. #endif
  559.         if (rc != EOK)
  560.             return rc;
  561.         process_answer(&call);
  562.  
  563.     } else {
  564.         IPC_SET_RETVAL(call.data, res);
  565.     }
  566.     rc = STRUCT_TO_USPACE(&data->args, &call.data.args);
  567.     if (rc != 0)
  568.         return rc;
  569.  
  570.     return 0;
  571. }
  572.  
  573. /** Make a synchronous IPC call allowing to transmit the entire payload.
  574.  *
  575.  * @param phoneid   Phone handle for the call.
  576.  * @param question  Userspace address of call data with the request.
  577.  * @param reply     Userspace address of call data where to store the
  578.  *          answer.
  579.  *
  580.  * @return      Zero on success or an error code.
  581.  */
  582. unative_t sys_ipc_call_sync_slow(unative_t phoneid, ipc_data_t *question,
  583.     ipc_data_t *reply)
  584. {
  585.     call_t call;
  586.     phone_t *phone;
  587.     int res;
  588.     int rc;
  589.  
  590.     ipc_call_static_init(&call);
  591.     rc = copy_from_uspace(&call.data.args, &question->args,
  592.         sizeof(call.data.args));
  593.     if (rc != 0)
  594.         return (unative_t) rc;
  595.  
  596.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  597.  
  598.     if (!(res = request_preprocess(&call, phone))) {
  599. #ifdef CONFIG_UDEBUG
  600.         udebug_stoppable_begin();
  601. #endif
  602.         rc = ipc_call_sync(phone, &call);
  603. #ifdef CONFIG_UDEBUG
  604.         udebug_stoppable_end();
  605. #endif
  606.         if (rc != EOK)
  607.             return rc;
  608.         process_answer(&call);
  609.     } else
  610.         IPC_SET_RETVAL(call.data, res);
  611.  
  612.     rc = STRUCT_TO_USPACE(&reply->args, &call.data.args);
  613.     if (rc != 0)
  614.         return rc;
  615.  
  616.     return 0;
  617. }
  618.  
  619. /** Check that the task did not exceed the allowed limit of asynchronous calls.
  620.  *
  621.  * @return      Return 0 if limit not reached or -1 if limit exceeded.
  622.  */
  623. static int check_call_limit(void)
  624. {
  625.     if (atomic_preinc(&TASK->active_calls) > IPC_MAX_ASYNC_CALLS) {
  626.         atomic_dec(&TASK->active_calls);
  627.         return -1;
  628.     }
  629.     return 0;
  630. }
  631.  
  632. /** Make a fast asynchronous call over IPC.
  633.  *
  634.  * This function can only handle four arguments of payload, but is faster than
  635.  * the generic function sys_ipc_call_async_slow().
  636.  *
  637.  * @param phoneid   Phone handle for the call.
  638.  * @param method    Method of the call.
  639.  * @param arg1      Service-defined payload argument.
  640.  * @param arg2      Service-defined payload argument.
  641.  * @param arg3      Service-defined payload argument.
  642.  * @param arg4      Service-defined payload argument.
  643.  *
  644.  * @return      Return call hash on success.
  645.  *          Return IPC_CALLRET_FATAL in case of a fatal error and
  646.  *          IPC_CALLRET_TEMPORARY if there are too many pending
  647.  *          asynchronous requests; answers should be handled first.
  648.  */
  649. unative_t sys_ipc_call_async_fast(unative_t phoneid, unative_t method,
  650.     unative_t arg1, unative_t arg2, unative_t arg3, unative_t arg4)
  651. {
  652.     call_t *call;
  653.     phone_t *phone;
  654.     int res;
  655.  
  656.     if (check_call_limit())
  657.         return IPC_CALLRET_TEMPORARY;
  658.  
  659.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  660.  
  661.     call = ipc_call_alloc(0);
  662.     IPC_SET_METHOD(call->data, method);
  663.     IPC_SET_ARG1(call->data, arg1);
  664.     IPC_SET_ARG2(call->data, arg2);
  665.     IPC_SET_ARG3(call->data, arg3);
  666.     IPC_SET_ARG4(call->data, arg4);
  667.     /*
  668.      * To achieve deterministic behavior, zero out arguments that are beyond
  669.      * the limits of the fast version.
  670.      */
  671.     IPC_SET_ARG5(call->data, 0);
  672.  
  673.     if (!(res = request_preprocess(call, phone)))
  674.         ipc_call(phone, call);
  675.     else
  676.         ipc_backsend_err(phone, call, res);
  677.  
  678.     return (unative_t) call;
  679. }
  680.  
  681. /** Make an asynchronous IPC call allowing to transmit the entire payload.
  682.  *
  683.  * @param phoneid   Phone handle for the call.
  684.  * @param data      Userspace address of call data with the request.
  685.  *
  686.  * @return      See sys_ipc_call_async_fast().
  687.  */
  688. unative_t sys_ipc_call_async_slow(unative_t phoneid, ipc_data_t *data)
  689. {
  690.     call_t *call;
  691.     phone_t *phone;
  692.     int res;
  693.     int rc;
  694.  
  695.     if (check_call_limit())
  696.         return IPC_CALLRET_TEMPORARY;
  697.  
  698.     GET_CHECK_PHONE(phone, phoneid, return IPC_CALLRET_FATAL);
  699.  
  700.     call = ipc_call_alloc(0);
  701.     rc = copy_from_uspace(&call->data.args, &data->args,
  702.         sizeof(call->data.args));
  703.     if (rc != 0) {
  704.         ipc_call_free(call);
  705.         return (unative_t) rc;
  706.     }
  707.     if (!(res = request_preprocess(call, phone)))
  708.         ipc_call(phone, call);
  709.     else
  710.         ipc_backsend_err(phone, call, res);
  711.  
  712.     return (unative_t) call;
  713. }
  714.  
  715. /** Forward a received call to another destination - common code for both the
  716.  * fast and the slow version.
  717.  *
  718.  * @param callid    Hash of the call to forward.
  719.  * @param phoneid   Phone handle to use for forwarding.
  720.  * @param method    New method to use for the forwarded call.
  721.  * @param arg1      New value of the first argument for the forwarded call.
  722.  * @param arg2      New value of the second argument for the forwarded call.
  723.  * @param arg3      New value of the third argument for the forwarded call.
  724.  * @param arg4      New value of the fourth argument for the forwarded call.
  725.  * @param arg5      New value of the fifth argument for the forwarded call.
  726.  * @param mode      Flags that specify mode of the forward operation.
  727.  * @param slow      If true, arg3, arg4 and arg5 are considered. Otherwise
  728.  *          the function considers only the fast version arguments:
  729.  *          i.e. arg1 and arg2.
  730.  *
  731.  * @return      Return 0 on succes, otherwise return an error code.
  732.  *
  733.  * Warning: Make sure that ARG5 is not rewritten for certain system IPC
  734.  */
  735. static unative_t sys_ipc_forward_common(unative_t callid, unative_t phoneid,
  736.     unative_t method, unative_t arg1, unative_t arg2, unative_t arg3,
  737.     unative_t arg4, unative_t arg5, int mode, bool slow)
  738. {
  739.     call_t *call;
  740.     phone_t *phone;
  741.  
  742.     call = get_call(callid);
  743.     if (!call)
  744.         return ENOENT;
  745.    
  746.     call->flags |= IPC_CALL_FORWARDED;
  747.  
  748.     GET_CHECK_PHONE(phone, phoneid, {
  749.         IPC_SET_RETVAL(call->data, EFORWARD);
  750.         ipc_answer(&TASK->answerbox, call);
  751.         return ENOENT;
  752.     });
  753.  
  754.     if (!method_is_forwardable(IPC_GET_METHOD(call->data))) {
  755.         IPC_SET_RETVAL(call->data, EFORWARD);
  756.         ipc_answer(&TASK->answerbox, call);
  757.         return EPERM;
  758.     }
  759.  
  760.     /*
  761.      * Userspace is not allowed to change method of system methods on
  762.      * forward, allow changing ARG1, ARG2, ARG3 and ARG4 by means of method,
  763.      * arg1, arg2 and arg3.
  764.      * If the method is immutable, don't change anything.
  765.      */
  766.     if (!method_is_immutable(IPC_GET_METHOD(call->data))) {
  767.         if (method_is_system(IPC_GET_METHOD(call->data))) {
  768.             if (IPC_GET_METHOD(call->data) == IPC_M_CONNECT_TO_ME)
  769.                 phone_dealloc(IPC_GET_ARG5(call->data));
  770.  
  771.             IPC_SET_ARG1(call->data, method);
  772.             IPC_SET_ARG2(call->data, arg1);
  773.             IPC_SET_ARG3(call->data, arg2);
  774.             if (slow) {
  775.                 IPC_SET_ARG4(call->data, arg3);
  776.                 /*
  777.                  * For system methods we deliberately don't
  778.                  * overwrite ARG5.
  779.                  */
  780.             }
  781.         } else {
  782.             IPC_SET_METHOD(call->data, method);
  783.             IPC_SET_ARG1(call->data, arg1);
  784.             IPC_SET_ARG2(call->data, arg2);
  785.             if (slow) {
  786.                 IPC_SET_ARG3(call->data, arg3);
  787.                 IPC_SET_ARG4(call->data, arg4);
  788.                 IPC_SET_ARG5(call->data, arg5);
  789.             }
  790.         }
  791.     }
  792.  
  793.     return ipc_forward(call, phone, &TASK->answerbox, mode);
  794. }
  795.  
  796. /** Forward a received call to another destination - fast version.
  797.  *
  798.  * @param callid    Hash of the call to forward.
  799.  * @param phoneid   Phone handle to use for forwarding.
  800.  * @param method    New method to use for the forwarded call.
  801.  * @param arg1      New value of the first argument for the forwarded call.
  802.  * @param arg2      New value of the second argument for the forwarded call.
  803.  * @param mode      Flags that specify mode of the forward operation.
  804.  *
  805.  * @return      Return 0 on succes, otherwise return an error code.
  806.  *
  807.  * In case the original method is a system method, ARG1, ARG2 and ARG3 are
  808.  * overwritten in the forwarded message with the new method and the new
  809.  * arg1 and arg2, respectively. Otherwise the METHOD, ARG1 and ARG2 are
  810.  * rewritten with the new method, arg1 and arg2, respectively. Also note there
  811.  * is a set of immutable methods, for which the new method and arguments are not
  812.  * set and these values are ignored.
  813.  */
  814. unative_t sys_ipc_forward_fast(unative_t callid, unative_t phoneid,
  815.     unative_t method, unative_t arg1, unative_t arg2, int mode)
  816. {
  817.     return sys_ipc_forward_common(callid, phoneid, method, arg1, arg2, 0, 0,
  818.         0, mode, false);
  819. }
  820.  
  821. /** Forward a received call to another destination - slow version.
  822.  *
  823.  * @param callid    Hash of the call to forward.
  824.  * @param phoneid   Phone handle to use for forwarding.
  825.  * @param data      Userspace address of the new IPC data.
  826.  * @param mode      Flags that specify mode of the forward operation.
  827.  *
  828.  * @return      Return 0 on succes, otherwise return an error code.
  829.  *
  830.  * This function is the slow verision of the sys_ipc_forward_fast interface.
  831.  * It can copy all five new arguments and the new method from the userspace.
  832.  * It naturally extends the functionality of the fast version. For system
  833.  * methods, it additionally stores the new value of arg3 to ARG4. For non-system
  834.  * methods, it additionally stores the new value of arg3, arg4 and arg5,
  835.  * respectively, to ARG3, ARG4 and ARG5, respectively.
  836.  */
  837. unative_t sys_ipc_forward_slow(unative_t callid, unative_t phoneid,
  838.     ipc_data_t *data, int mode)
  839. {
  840.     ipc_data_t newdata;
  841.     int rc;
  842.  
  843.     rc = copy_from_uspace(&newdata.args, &data->args,
  844.         sizeof(newdata.args));
  845.     if (rc != 0)
  846.         return (unative_t) rc;
  847.  
  848.     return sys_ipc_forward_common(callid, phoneid,
  849.         IPC_GET_METHOD(newdata), IPC_GET_ARG1(newdata),
  850.         IPC_GET_ARG2(newdata), IPC_GET_ARG3(newdata),
  851.         IPC_GET_ARG4(newdata), IPC_GET_ARG5(newdata), mode, true);
  852. }
  853.  
  854. /** Answer an IPC call - fast version.
  855.  *
  856.  * This function can handle only two return arguments of payload, but is faster
  857.  * than the generic sys_ipc_answer().
  858.  *
  859.  * @param callid    Hash of the call to be answered.
  860.  * @param retval    Return value of the answer.
  861.  * @param arg1      Service-defined return value.
  862.  * @param arg2      Service-defined return value.
  863.  * @param arg3      Service-defined return value.
  864.  * @param arg4      Service-defined return value.
  865.  *
  866.  * @return      Return 0 on success, otherwise return an error code.   
  867.  */
  868. unative_t sys_ipc_answer_fast(unative_t callid, unative_t retval,
  869.     unative_t arg1, unative_t arg2, unative_t arg3, unative_t arg4)
  870. {
  871.     call_t *call;
  872.     ipc_data_t saved_data;
  873.     int saveddata = 0;
  874.     int rc;
  875.  
  876.     /* Do not answer notification callids */
  877.     if (callid & IPC_CALLID_NOTIFICATION)
  878.         return 0;
  879.  
  880.     call = get_call(callid);
  881.     if (!call)
  882.         return ENOENT;
  883.  
  884.     if (answer_need_old(call)) {
  885.         memcpy(&saved_data, &call->data, sizeof(call->data));
  886.         saveddata = 1;
  887.     }
  888.  
  889.     IPC_SET_RETVAL(call->data, retval);
  890.     IPC_SET_ARG1(call->data, arg1);
  891.     IPC_SET_ARG2(call->data, arg2);
  892.     IPC_SET_ARG3(call->data, arg3);
  893.     IPC_SET_ARG4(call->data, arg4);
  894.     /*
  895.      * To achieve deterministic behavior, zero out arguments that are beyond
  896.      * the limits of the fast version.
  897.      */
  898.     IPC_SET_ARG5(call->data, 0);
  899.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  900.  
  901.     ipc_answer(&TASK->answerbox, call);
  902.     return rc;
  903. }
  904.  
  905. /** Answer an IPC call.
  906.  *
  907.  * @param callid    Hash of the call to be answered.
  908.  * @param data      Userspace address of call data with the answer.
  909.  *
  910.  * @return      Return 0 on success, otherwise return an error code.
  911.  */
  912. unative_t sys_ipc_answer_slow(unative_t callid, ipc_data_t *data)
  913. {
  914.     call_t *call;
  915.     ipc_data_t saved_data;
  916.     int saveddata = 0;
  917.     int rc;
  918.  
  919.     /* Do not answer notification callids */
  920.     if (callid & IPC_CALLID_NOTIFICATION)
  921.         return 0;
  922.  
  923.     call = get_call(callid);
  924.     if (!call)
  925.         return ENOENT;
  926.  
  927.     if (answer_need_old(call)) {
  928.         memcpy(&saved_data, &call->data, sizeof(call->data));
  929.         saveddata = 1;
  930.     }
  931.     rc = copy_from_uspace(&call->data.args, &data->args,
  932.         sizeof(call->data.args));
  933.     if (rc != 0)
  934.         return rc;
  935.  
  936.     rc = answer_preprocess(call, saveddata ? &saved_data : NULL);
  937.    
  938.     ipc_answer(&TASK->answerbox, call);
  939.  
  940.     return rc;
  941. }
  942.  
  943. /** Hang up a phone.
  944.  *
  945.  * @param       Phone handle of the phone to be hung up.
  946.  *
  947.  * @return      Return 0 on success or an error code.
  948.  */
  949. unative_t sys_ipc_hangup(int phoneid)
  950. {
  951.     phone_t *phone;
  952.  
  953.     GET_CHECK_PHONE(phone, phoneid, return ENOENT);
  954.  
  955.     if (ipc_phone_hangup(phone))
  956.         return -1;
  957.  
  958.     return 0;
  959. }
  960.  
  961. /** Wait for an incoming IPC call or an answer.
  962.  *
  963.  * @param calldata  Pointer to buffer where the call/answer data is stored.
  964.  * @param usec      Timeout. See waitq_sleep_timeout() for explanation.
  965.  * @param flags     Select mode of sleep operation. See waitq_sleep_timeout()
  966.  *          for explanation.
  967.  *
  968.  * @return      Hash of the call.
  969.  *          If IPC_CALLID_NOTIFICATION bit is set in the hash, the
  970.  *          call is a notification. IPC_CALLID_ANSWERED denotes an
  971.  *          answer.
  972.  */
  973. unative_t sys_ipc_wait_for_call(ipc_data_t *calldata, uint32_t usec, int flags)
  974. {
  975.     call_t *call;
  976.  
  977. restart:
  978.  
  979. #ifdef CONFIG_UDEBUG
  980.     udebug_stoppable_begin();
  981. #endif 
  982.     call = ipc_wait_for_call(&TASK->answerbox, usec,
  983.         flags | SYNCH_FLAGS_INTERRUPTIBLE);
  984.  
  985. #ifdef CONFIG_UDEBUG
  986.     udebug_stoppable_end();
  987. #endif
  988.     if (!call)
  989.         return 0;
  990.  
  991.     if (call->flags & IPC_CALL_NOTIF) {
  992.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  993.  
  994.         /* Set in_phone_hash to the interrupt counter */
  995.         call->data.phone = (void *) call->priv;
  996.        
  997.         STRUCT_TO_USPACE(calldata, &call->data);
  998.  
  999.         ipc_call_free(call);
  1000.        
  1001.         return ((unative_t) call) | IPC_CALLID_NOTIFICATION;
  1002.     }
  1003.  
  1004.     if (call->flags & IPC_CALL_ANSWERED) {
  1005.         process_answer(call);
  1006.  
  1007.         ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC));
  1008.  
  1009.         if (call->flags & IPC_CALL_DISCARD_ANSWER) {
  1010.             ipc_call_free(call);
  1011.             goto restart;
  1012.         } else {
  1013.             /*
  1014.              * Decrement the counter of active calls only if the
  1015.              * call is not an answer to IPC_M_PHONE_HUNGUP,
  1016.              * which doesn't contribute to the counter.
  1017.              */
  1018.             atomic_dec(&TASK->active_calls);
  1019.         }
  1020.  
  1021.         STRUCT_TO_USPACE(&calldata->args, &call->data.args);
  1022.         ipc_call_free(call);
  1023.  
  1024.         return ((unative_t) call) | IPC_CALLID_ANSWERED;
  1025.     }
  1026.  
  1027.     if (process_request(&TASK->answerbox, call))
  1028.         goto restart;
  1029.  
  1030.     /* Include phone address('id') of the caller in the request,
  1031.      * copy whole call->data, not only call->data.args */
  1032.     if (STRUCT_TO_USPACE(calldata, &call->data)) {
  1033.         /*
  1034.          * The callee will not receive this call and no one else has
  1035.          * a chance to answer it. Reply with the EPARTY error code.
  1036.          */
  1037.         ipc_data_t saved_data;
  1038.         int saveddata = 0;
  1039.  
  1040.         if (answer_need_old(call)) {
  1041.             memcpy(&saved_data, &call->data, sizeof(call->data));
  1042.             saveddata = 1;
  1043.         }
  1044.        
  1045.         IPC_SET_RETVAL(call->data, EPARTY);
  1046.         (void) answer_preprocess(call, saveddata ? &saved_data : NULL);
  1047.         ipc_answer(&TASK->answerbox, call);
  1048.         return 0;
  1049.     }
  1050.     return (unative_t)call;
  1051. }
  1052.  
  1053. /** Connect an IRQ handler to a task.
  1054.  *
  1055.  * @param inr       IRQ number.
  1056.  * @param devno     Device number.
  1057.  * @param method    Method to be associated with the notification.
  1058.  * @param ucode     Uspace pointer to the top-half pseudocode.
  1059.  *
  1060.  * @return      EPERM or a return code returned by ipc_irq_register().
  1061.  */
  1062. unative_t sys_ipc_register_irq(inr_t inr, devno_t devno, unative_t method,
  1063.     irq_code_t *ucode)
  1064. {
  1065.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  1066.         return EPERM;
  1067.  
  1068.     return ipc_irq_register(&TASK->answerbox, inr, devno, method, ucode);
  1069. }
  1070.  
  1071. /** Disconnect an IRQ handler from a task.
  1072.  *
  1073.  * @param inr       IRQ number.
  1074.  * @param devno     Device number.
  1075.  *
  1076.  * @return      Zero on success or EPERM on error..
  1077.  */
  1078. unative_t sys_ipc_unregister_irq(inr_t inr, devno_t devno)
  1079. {
  1080.     if (!(cap_get(TASK) & CAP_IRQ_REG))
  1081.         return EPERM;
  1082.  
  1083.     ipc_irq_unregister(&TASK->answerbox, inr, devno);
  1084.  
  1085.     return 0;
  1086. }
  1087.  
  1088. #include <console/console.h>
  1089.  
  1090. /**
  1091.  * Syscall connect to a task by id.
  1092.  *
  1093.  * @return      Phone id on success, or negative error code.
  1094.  */
  1095. unative_t sys_ipc_connect_kbox(sysarg64_t *uspace_taskid_arg)
  1096. {
  1097. #ifdef CONFIG_UDEBUG
  1098.     sysarg64_t taskid_arg;
  1099.     int rc;
  1100.    
  1101.     rc = copy_from_uspace(&taskid_arg, uspace_taskid_arg, sizeof(sysarg64_t));
  1102.     if (rc != 0)
  1103.         return (unative_t) rc;
  1104.  
  1105.     LOG("sys_ipc_connect_kbox(%" PRIu64 ")\n", taskid_arg.value);
  1106.  
  1107.     return ipc_connect_kbox(taskid_arg.value);
  1108. #else
  1109.     return (unative_t) ENOTSUP;
  1110. #endif
  1111. }
  1112.  
  1113. /** @}
  1114.  */
  1115.