WebSVN – HelenOS – Diff – /branches/dd/uspace/lib/libc/generic/ipc.c


/*
 * Copyright (c) 2006 Ondrej Palkovsky
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup libc
 * @{
 * @}
 */
 
/** @addtogroup libcipc IPC
 * @brief HelenOS uspace IPC
 * @{
 * @ingroup libc
 */
/** @file
 */
 
#include <ipc/ipc.h>
#include <libc.h>
#include <malloc.h>
#include <errno.h>
#include <libadt/list.h>
#include <stdio.h>
#include <unistd.h>
#include <futex.h>
#include <kernel/synch/synch.h>
#include <async.h>
#include <fibril.h>
#include <assert.h>
 
/**
 * Structures of this type are used for keeping track of sent asynchronous calls
 * and queing unsent calls.
 */
typedef struct {
    link_t list;
 
    ipc_async_callback_t callback;
    void *private;
    union {
        ipc_callid_t callid;
        struct {
            ipc_call_t data;
            int phoneid;
        } msg;
    } u;
    fid_t fid;  /**< Fibril waiting for sending this call. */
} async_call_t;
 
LIST_INITIALIZE(dispatched_calls);
 
/** List of asynchronous calls that were not accepted by kernel.
 *
 * It is protected by async_futex, because if the call cannot be sent into the
 * kernel, the async framework is used automatically.
 */
LIST_INITIALIZE(queued_calls);
 
static atomic_t ipc_futex = FUTEX_INITIALIZER;
 
/** Make a fast synchronous call.
 *
 * Only one payload argument can be passed using this function. However, this
 * function is faster than the generic ipc_call_sync_3().
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param result    If non-NULL, the return ARG1 will be stored there.
 *
 * @return      Negative values represent errors returned by IPC.
 *          Otherwise the RETVAL of the answer is returned.
 */
int ipc_call_sync(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t *result)
{
    ipc_call_t resdata;
    int callres;
   
    callres = __SYSCALL4(SYS_IPC_CALL_SYNC_FAST, phoneid, method, arg1,
        (sysarg_t) &resdata);
    if (callres)
        return callres;
    if (result)
        *result = IPC_GET_ARG1(resdata);
    return IPC_GET_RETVAL(resdata);
}
 
/** Make a synchronous call transmitting 3 arguments of payload.
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param arg3      Service-defined payload argument.
 * @param result1   If non-NULL, storage for the first return argument.
 * @param result2   If non-NULL, storage for the second return argument.
 * @param result3   If non-NULL, storage for the third return argument.
 *
 * @return      Negative value means IPC error.
 *          Otherwise the RETVAL of the answer.
 */
int ipc_call_sync_3(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
    ipcarg_t arg3, ipcarg_t *result1, ipcarg_t *result2, ipcarg_t *result3)
{
    ipc_call_t data;
    int callres;
 
    IPC_SET_METHOD(data, method);
    IPC_SET_ARG1(data, arg1);
    IPC_SET_ARG2(data, arg2);
    IPC_SET_ARG3(data, arg3);
 
    callres = __SYSCALL3(SYS_IPC_CALL_SYNC, phoneid, (sysarg_t) &data,
        (sysarg_t) &data);
    if (callres)
        return callres;
 
    if (result1)
        *result1 = IPC_GET_ARG1(data);
    if (result2)
        *result2 = IPC_GET_ARG2(data);
    if (result3)
        *result3 = IPC_GET_ARG3(data);
    return IPC_GET_RETVAL(data);
}
 
/** Syscall to send asynchronous message.
 *
 * @param phoneid   Phone handle for the call.
 * @param data      Call data with the request.
 *
 * @return      Hash of the call or an error code.
 */
static ipc_callid_t _ipc_call_async(int phoneid, ipc_call_t *data)
{
    return __SYSCALL2(SYS_IPC_CALL_ASYNC, phoneid, (sysarg_t) data);
}
 
/** Prolog to ipc_call_async_*() functions.
 *
 * @param private   Argument for the answer/error callback.
 * @param callback  Answer/error callback.
 *
 * @return      New, partially initialized async_call structure or NULL.
 */
static inline async_call_t *ipc_prepare_async(void *private,
    ipc_async_callback_t callback)
{
    async_call_t *call;
 
    call = malloc(sizeof(*call));
    if (!call) {
        if (callback)
            callback(private, ENOMEM, NULL);
        return NULL;
    }
    call->callback = callback;
    call->private = private;
 
    return call;
}
 
/** Epilogue of ipc_call_async_*() functions.
 *
 * @param callid    Value returned by the SYS_IPC_CALL_ASYNC_* syscall.
 * @param phoneid   Phone handle through which the call was made.
 * @param call      async_call structure returned by ipc_prepare_async().
 * @param can_preempt   If non-zero, the current fibril can be preempted in this
 *          call.
 */
static inline void ipc_finish_async(ipc_callid_t callid, int phoneid,
    async_call_t *call, int can_preempt)
{
    if (!call) { /* Nothing to do regardless if failed or not */
        futex_up(&ipc_futex);
        return;
    }
 
    if (callid == IPC_CALLRET_FATAL) {
        futex_up(&ipc_futex);
        /* Call asynchronous handler with error code */
        if (call->callback)
            call->callback(call->private, ENOENT, NULL);
        free(call);
        return;
    }
 
    if (callid == IPC_CALLRET_TEMPORARY) {
        futex_up(&ipc_futex);
 
        call->u.msg.phoneid = phoneid;
       
        futex_down(&async_futex);
        list_append(&call->list, &queued_calls);
 
        if (can_preempt) {
            call->fid = fibril_get_id();
            fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
            /* Async futex unlocked by previous call */
        } else {
            call->fid = 0;
            futex_up(&async_futex);
        }
        return;
    }
    call->u.callid = callid;
    /* Add call to the list of dispatched calls */
    list_append(&call->list, &dispatched_calls);
    futex_up(&ipc_futex);
   
}
 
/** Make a fast asynchronous call.
 *
 * This function can only handle two arguments of payload. It is, however,
 * faster than the more generic ipc_call_async_3().
 *
 * Note that this function is a void function.
 * During normal opertation, answering this call will trigger the callback.
 * In case of fatal error, call the callback handler with the proper error code.
 * If the call cannot be temporarily made, queue it.
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param private   Argument to be passed to the answer/error callback.
 * @param callback  Answer or error callback.
 * @param can_preempt   If non-zero, the current fibril will be preempted in
 *          case the kernel temporarily refuses to accept more
 *          asynchronous calls.
 */
void ipc_call_async_2(int phoneid, ipcarg_t method, ipcarg_t arg1,
    ipcarg_t arg2, void *private, ipc_async_callback_t callback,
    int can_preempt)
{
    async_call_t *call = NULL;
    ipc_callid_t callid;
 
    if (callback) {
        call = ipc_prepare_async(private, callback);
        if (!call)
            return;
    }
 
    /*
     * We need to make sure that we get callid before another thread
     * accesses the queue again.
     */
    futex_down(&ipc_futex);
    callid = __SYSCALL4(SYS_IPC_CALL_ASYNC_FAST, phoneid, method, arg1,
        arg2);
 
    if (callid == IPC_CALLRET_TEMPORARY) {
        if (!call) {
            call = ipc_prepare_async(private, callback);
            if (!call)
                return;
        }
        IPC_SET_METHOD(call->u.msg.data, method);
        IPC_SET_ARG1(call->u.msg.data, arg1);
        IPC_SET_ARG2(call->u.msg.data, arg2);
    }
    ipc_finish_async(callid, phoneid, call, can_preempt);
}
 
/** Make an asynchronous call transmitting the entire payload.
 *
 * Note that this function is a void function.
 * During normal opertation, answering this call will trigger the callback.
 * In case of fatal error, call the callback handler with the proper error code.
 * If the call cannot be temporarily made, queue it.
 *
 * @param phoneid   Phone handle for the call.
 * @param method    Requested method.
 * @param arg1      Service-defined payload argument.
 * @param arg2      Service-defined payload argument.
 * @param arg3      Service-defined payload argument.
 * @param private   Argument to be passed to the answer/error callback.
 * @param callback  Answer or error callback.
 * @param can_preempt   If non-zero, the current fibril will be preempted in
 *          case the kernel temporarily refuses to accept more
 *          asynchronous calls.
 *
 */
void ipc_call_async_3(int phoneid, ipcarg_t method, ipcarg_t arg1,
    ipcarg_t arg2, ipcarg_t arg3, void *private, ipc_async_callback_t callback,
    int can_preempt)
{
    async_call_t *call;
    ipc_callid_t callid;
 
    call = ipc_prepare_async(private, callback);
    if (!call)
        return;
 
    IPC_SET_METHOD(call->u.msg.data, method);
    IPC_SET_ARG1(call->u.msg.data, arg1);
    IPC_SET_ARG2(call->u.msg.data, arg2);
    IPC_SET_ARG3(call->u.msg.data, arg3);
    /*
     * We need to make sure that we get callid before another thread accesses
     * the queue again.
     */
    futex_down(&ipc_futex);
    callid = _ipc_call_async(phoneid, &call->u.msg.data);
 
    ipc_finish_async(callid, phoneid, call, can_preempt);
}
 
 
/** Answer a received call - fast version.
 *
 * The fast answer makes use of passing retval and first two arguments in
 * registers. If you need to return more, use the ipc_answer() instead.
 *
 * @param callid    Hash of the call being answered.
 * @param retval    Return value.
 * @param arg1      First return argument.
 * @param arg2      Second return argument.
 *
 * @return      Zero on success or a value from @ref errno.h on failure.
 */
ipcarg_t ipc_answer_fast(ipc_callid_t callid, ipcarg_t retval, ipcarg_t arg1,
    ipcarg_t arg2)
{
    return __SYSCALL4(SYS_IPC_ANSWER_FAST, callid, retval, arg1, arg2);
}
 
/** Answer a received call - full version.
 *
 * @param callid    Hash of the call being answered.
 * @param call      Call structure with the answer.
 *          Must be already initialized by the responder.
 *
 * @return      Zero on success or a value from @ref errno.h on failure.
 */
ipcarg_t ipc_answer(ipc_callid_t callid, ipc_call_t *call)
{
    return __SYSCALL2(SYS_IPC_ANSWER, callid, (sysarg_t) call);
}
 
 
/** Try to dispatch queued calls from the async queue. */
static void try_dispatch_queued_calls(void)
{
    async_call_t *call;
    ipc_callid_t callid;
 
    /** @todo
     * Integrate intelligently ipc_futex, so that it is locked during
     * ipc_call_async_*(), until it is added to dispatched_calls.
     */
    futex_down(&async_futex);
    while (!list_empty(&queued_calls)) {
        call = list_get_instance(queued_calls.next, async_call_t, list);
        callid = _ipc_call_async(call->u.msg.phoneid, &call->u.msg.data);
        if (callid == IPC_CALLRET_TEMPORARY) {
            break;
        }
        list_remove(&call->list);
 
        futex_up(&async_futex);
        if (call->fid)
            fibril_add_ready(call->fid);
       
        if (callid == IPC_CALLRET_FATAL) {
            if (call->callback)
                call->callback(call->private, ENOENT, NULL);
            free(call);
        } else {
            call->u.callid = callid;
            futex_down(&ipc_futex);
            list_append(&call->list, &dispatched_calls);
            futex_up(&ipc_futex);
        }
        futex_down(&async_futex);
    }
    futex_up(&async_futex);
}
 
/** Handle a received answer.
 *
 * Find the hash of the answer and call the answer callback.
 *
 * @todo Make it use hash table.
 *
 * @param callid    Hash of the received answer.
 *          The answer has the same hash as the request OR'ed with
 *          the IPC_CALLID_ANSWERED bit.
 * @param data      Call data of the answer.
 */
static void handle_answer(ipc_callid_t callid, ipc_call_t *data)
{
    link_t *item;
    async_call_t *call;
 
    callid &= ~IPC_CALLID_ANSWERED;
   
    futex_down(&ipc_futex);
    for (item = dispatched_calls.next; item != &dispatched_calls;
        item = item->next) {
        call = list_get_instance(item, async_call_t, list);
        if (call->u.callid == callid) {
            list_remove(&call->list);
            futex_up(&ipc_futex);
            if (call->callback)
                call->callback(call->private,
                    IPC_GET_RETVAL(*data), data);
            free(call);
            return;
        }
    }
    futex_up(&ipc_futex);
}
 
 
/** Wait for a first call to come.
 *
 * @param call      Storage where the incoming call data will be stored.
 * @param usec      Timeout in microseconds
 * @param flags     Flags passed to SYS_IPC_WAIT (blocking, nonblocking).
 *
 * @return      Hash of the call. Note that certain bits have special
 *          meaning. IPC_CALLID_ANSWERED will be set in an answer
 *          and IPC_CALLID_NOTIFICATION is used for notifications.
 *         
 */
ipc_callid_t ipc_wait_cycle(ipc_call_t *call, uint32_t usec, int flags)
{
    ipc_callid_t callid;
 
    callid = __SYSCALL3(SYS_IPC_WAIT, (sysarg_t) call, usec, flags);
    /* Handle received answers */
    if (callid & IPC_CALLID_ANSWERED) {
        handle_answer(callid, call);
        try_dispatch_queued_calls();
    }
 
    return callid;
}
 
/** Wait some time for an IPC call.
 *
 * The call will return after an answer is received.
 *
 * @param call      Storage where the incoming call data will be stored.
 * @param usec      Timeout in microseconds.
 *
 * @return      Hash of the answer.
 */
ipc_callid_t ipc_wait_for_call_timeout(ipc_call_t *call, uint32_t usec)
{
    ipc_callid_t callid;
 
    do {
        callid = ipc_wait_cycle(call, usec, SYNCH_FLAGS_NONE);
    } while (callid & IPC_CALLID_ANSWERED);
 
    return callid;
}
 
/** Check if there is an IPC call waiting to be picked up.
 *
 * @param call      Storage where the incoming call will be stored.
 * @return      Hash of the answer.
 */
ipc_callid_t ipc_trywait_for_call(ipc_call_t *call)
{
    ipc_callid_t callid;
 
    do {
        callid = ipc_wait_cycle(call, SYNCH_NO_TIMEOUT,
            SYNCH_FLAGS_NON_BLOCKING);
    } while (callid & IPC_CALLID_ANSWERED);
 
    return callid;
}
 
/** Ask destination to do a callback connection.
 *
 * @param phoneid   Phone handle used for contacting the other side.
 * @param arg1      Service-defined argument.
 * @param arg2      Service-defined argument.
 * @param phonehash Storage where the library will store an opaque
 *          identifier of the phone that will be used for incoming
 *          calls. This identifier can be used for connection
 *          tracking.
 *
 * @return      Zero on success or a negative error code.
 */
int ipc_connect_to_me(int phoneid, int arg1, int arg2, ipcarg_t *phonehash)
{
    return ipc_call_sync_3(phoneid, IPC_M_CONNECT_TO_ME, arg1, arg2, 0, 0, 0,
        phonehash);
}
 
/** Ask through phone for a new connection to some service.
 *
 * @param phoneid   Phone handle used for contacting the other side.
 * @param arg1      User defined argument.
 * @param arg2      User defined argument.
 *
 * @return      New phone handle on success or a negative error code.
 */
int ipc_connect_me_to(int phoneid, int arg1, int arg2)
{
    ipcarg_t newphid;
    int res;
 
    res =  ipc_call_sync_3(phoneid, IPC_M_CONNECT_ME_TO, arg1, arg2, 0, 0, 0,
        &newphid);
    if (res)
        return res;
    return newphid;
}
 
/** Hang up a phone.
 *
 * @param phoneid   Handle of the phone to be hung up.
 *
 * @return      Zero on success or a negative error code.
 */
int ipc_hangup(int phoneid)
{
    return __SYSCALL1(SYS_IPC_HANGUP, phoneid);
}
 
/** Register IRQ notification.
 *
 * @param inr       IRQ number.
 * @param devno     Device number of the device generating inr.
 * @param method    Use this method for notifying me.
 * @param ucode     Top-half pseudocode handler.
 *
 * @return      Value returned by the kernel.
 */
int ipc_register_irq(int inr, int devno, int method, irq_code_t *ucode)
{
    return __SYSCALL4(SYS_IPC_REGISTER_IRQ, inr, devno, method,
        (sysarg_t) ucode);
}
 
/** Unregister IRQ notification.
 *
 * @param inr       IRQ number.
 * @param devno     Device number of the device generating inr.
 *
 * @return      Value returned by the kernel.
 */
int ipc_unregister_irq(int inr, int devno)
{
    return __SYSCALL2(SYS_IPC_UNREGISTER_IRQ, inr, devno);
}
 
/** Forward a received call to another destination.
 *
 * @param callid    Hash of the call to forward.
 * @param phoneid   Phone handle to use for forwarding.
 * @param method    New method for the forwarded call.
 * @param arg1      New value of the first argument for the forwarded call.
 *
 * @return      Zero on success or an error code.
 *
 * For non-system methods, the old method and arg1 are rewritten by the new
 * values. For system methods, the new method and arg1 are written to the old
 * arg1 and arg2, respectivelly.
 */
int ipc_forward_fast(ipc_callid_t callid, int phoneid, int method, ipcarg_t arg1)
{
    return __SYSCALL4(SYS_IPC_FORWARD_FAST, callid, phoneid, method, arg1);
}
 
/** Wrapper for accepting the IPC_M_DATA_SEND calls.
 *
 * This wrapper only makes it more comfortable to accept IPC_M_DATA_SEND calls
 * so that the user doesn't have to remember the meaning of each IPC argument.
 *
 * So far, this wrapper is to be used from within a connection fibril.
 *
 * @param callid    Storage where the hash of the IPC_M_DATA_SEND call will
 *          be stored.
 * @param call      Storage where the incoming call will be stored.
 * @param dst       Storage where the suggested destination address will
 *          be stored. May be NULL.
 * @param size      Storage where the suggested size will be stored. May be
 *          NULL
 *
 * @return      Non-zero on success, zero on failure.
 */
int ipc_data_send_accept(ipc_callid_t *callid, ipc_call_t *call, void **dst,
    size_t *size)
{
    assert(callid);
    assert(call);
 
    *callid = async_get_call(call);
    if (IPC_GET_METHOD(*call) != IPC_M_DATA_SEND)
        return 0;
    if (dst)
        *dst = (void *) IPC_GET_ARG1(*call);
    if (size)
        *size = (size_t) IPC_GET_ARG3(*call);
    return 1;
}
 
/** Wrapper for answering the IPC_M_DATA_SEND calls.
 *
 * This wrapper only makes it more comfortable to answer IPC_M_DATA_SEND calls
 * so that the user doesn't have to remember the meaning of each IPC argument.
 *
 * @param callid    Hash of the IPC_M_DATA_SEND call to answer.
 * @param call      Call structure with the request.
 * @param dst       Final destination address for the IPC_M_DATA_SEND call.
 * @param size      Final size for the IPC_M_DATA_SEND call.
 *
 * @return      Zero on success or a value from @ref errno.h on failure.
 */
ipcarg_t ipc_data_send_answer(ipc_callid_t callid, ipc_call_t *call, void *dst,     size_t size)
{
    IPC_SET_RETVAL(*call, EOK);
    IPC_SET_ARG1(*call, (ipcarg_t) dst);
    IPC_SET_ARG3(*call, (ipcarg_t) size);
    return ipc_answer(callid, call);
}
 
/** @}
 */
 

Rev 2522	Rev 2530
1	/*	1	/*
2	* Copyright (c) 2006 Ondrej Palkovsky	2	* Copyright (c) 2006 Ondrej Palkovsky
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	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	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.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	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	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	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	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	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	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.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup libc	29	/** @addtogroup libc
30	* @{	30	* @{
31	* @}	31	* @}
32	*/	32	*/
33		33
34	/** @addtogroup libcipc IPC	34	/** @addtogroup libcipc IPC
35	* @brief HelenOS uspace IPC	35	* @brief HelenOS uspace IPC
36	* @{	36	* @{
37	* @ingroup libc	37	* @ingroup libc
38	*/	38	*/
39	/** @file	39	/** @file
40	*/	40	*/
41		41
42	#include <ipc/ipc.h>	42	#include <ipc/ipc.h>
43	#include <libc.h>	43	#include <libc.h>
44	#include <malloc.h>	44	#include <malloc.h>
45	#include <errno.h>	45	#include <errno.h>
46	#include <libadt/list.h>	46	#include <libadt/list.h>
47	#include <stdio.h>	47	#include <stdio.h>
48	#include <unistd.h>	48	#include <unistd.h>
49	#include <futex.h>	49	#include <futex.h>
50	#include <kernel/synch/synch.h>	50	#include <kernel/synch/synch.h>
51	#include <async.h>	51	#include <async.h>
52	#include <fibril.h>	52	#include <fibril.h>
53	#include <assert.h>	53	#include <assert.h>
54		54
55	/**	55	/**
56	* Structures of this type are used for keeping track of sent asynchronous calls	56	* Structures of this type are used for keeping track of sent asynchronous calls
57	* and queing unsent calls.	57	* and queing unsent calls.
58	*/	58	*/
59	typedef struct {	59	typedef struct {
60	link_t list;	60	link_t list;
61		61
62	ipc_async_callback_t callback;	62	ipc_async_callback_t callback;
63	void *private;	63	void *private;
64	union {	64	union {
65	ipc_callid_t callid;	65	ipc_callid_t callid;
66	struct {	66	struct {
67	ipc_call_t data;	67	ipc_call_t data;
68	int phoneid;	68	int phoneid;
69	} msg;	69	} msg;
70	} u;	70	} u;
71	fid_t fid; /*< Fibril waiting for sending this call. /	71	fid_t fid; /*< Fibril waiting for sending this call. /
72	} async_call_t;	72	} async_call_t;
73		73
74	LIST_INITIALIZE(dispatched_calls);	74	LIST_INITIALIZE(dispatched_calls);
75		75
76	/** List of asynchronous calls that were not accepted by kernel.	76	/** List of asynchronous calls that were not accepted by kernel.
77	*	77	*
78	* It is protected by async_futex, because if the call cannot be sent into the	78	* It is protected by async_futex, because if the call cannot be sent into the
79	* kernel, the async framework is used automatically.	79	* kernel, the async framework is used automatically.
80	*/	80	*/
81	LIST_INITIALIZE(queued_calls);	81	LIST_INITIALIZE(queued_calls);
82		82
83	static atomic_t ipc_futex = FUTEX_INITIALIZER;	83	static atomic_t ipc_futex = FUTEX_INITIALIZER;
84		84
85	/** Make a fast synchronous call.	85	/** Make a fast synchronous call.
86	*	86	*
87	* Only one payload argument can be passed using this function. However, this	87	* Only one payload argument can be passed using this function. However, this
88	* function is faster than the generic ipc_call_sync_3().	88	* function is faster than the generic ipc_call_sync_3().
89	*	89	*
90	* @param phoneid Phone handle for the call.	90	* @param phoneid Phone handle for the call.
91	* @param method Requested method.	91	* @param method Requested method.
92	* @param arg1 Service-defined payload argument.	92	* @param arg1 Service-defined payload argument.
93	* @param result If non-NULL, the return ARG1 will be stored there.	93	* @param result If non-NULL, the return ARG1 will be stored there.
94	*	94	*
95	* @return Negative values represent errors returned by IPC.	95	* @return Negative values represent errors returned by IPC.
96	* Otherwise the RETVAL of the answer is returned.	96	* Otherwise the RETVAL of the answer is returned.
97	*/	97	*/
98	int ipc_call_sync(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t *result)	98	int ipc_call_sync(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t *result)
99	{	99	{
100	ipc_call_t resdata;	100	ipc_call_t resdata;
101	int callres;	101	int callres;
102		102
103	callres = __SYSCALL4(SYS_IPC_CALL_SYNC_FAST, phoneid, method, arg1,	103	callres = __SYSCALL4(SYS_IPC_CALL_SYNC_FAST, phoneid, method, arg1,
104	(sysarg_t) &resdata);	104	(sysarg_t) &resdata);
105	if (callres)	105	if (callres)
106	return callres;	106	return callres;
107	if (result)	107	if (result)
108	*result = IPC_GET_ARG1(resdata);	108	*result = IPC_GET_ARG1(resdata);
109	return IPC_GET_RETVAL(resdata);	109	return IPC_GET_RETVAL(resdata);
110	}	110	}
111		111
112	/** Make a synchronous call transmitting 3 arguments of payload.	112	/** Make a synchronous call transmitting 3 arguments of payload.
113	*	113	*
114	* @param phoneid Phone handle for the call.	114	* @param phoneid Phone handle for the call.
115	* @param method Requested method.	115	* @param method Requested method.
116	* @param arg1 Service-defined payload argument.	116	* @param arg1 Service-defined payload argument.
117	* @param arg2 Service-defined payload argument.	117	* @param arg2 Service-defined payload argument.
118	* @param arg3 Service-defined payload argument.	118	* @param arg3 Service-defined payload argument.
119	* @param result1 If non-NULL, storage for the first return argument.	119	* @param result1 If non-NULL, storage for the first return argument.
120	* @param result2 If non-NULL, storage for the second return argument.	120	* @param result2 If non-NULL, storage for the second return argument.
121	* @param result3 If non-NULL, storage for the third return argument.	121	* @param result3 If non-NULL, storage for the third return argument.
122	*	122	*
123	* @return Negative value means IPC error.	123	* @return Negative value means IPC error.
124	* Otherwise the RETVAL of the answer.	124	* Otherwise the RETVAL of the answer.
125	*/	125	*/
126	int ipc_call_sync_3(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,	126	int ipc_call_sync_3(int phoneid, ipcarg_t method, ipcarg_t arg1, ipcarg_t arg2,
127	ipcarg_t arg3, ipcarg_t result1, ipcarg_t result2, ipcarg_t *result3)	127	ipcarg_t arg3, ipcarg_t result1, ipcarg_t result2, ipcarg_t *result3)
128	{	128	{
129	ipc_call_t data;	129	ipc_call_t data;
130	int callres;	130	int callres;
131		131
132	IPC_SET_METHOD(data, method);	132	IPC_SET_METHOD(data, method);
133	IPC_SET_ARG1(data, arg1);	133	IPC_SET_ARG1(data, arg1);
134	IPC_SET_ARG2(data, arg2);	134	IPC_SET_ARG2(data, arg2);
135	IPC_SET_ARG3(data, arg3);	135	IPC_SET_ARG3(data, arg3);
136		136
137	callres = __SYSCALL3(SYS_IPC_CALL_SYNC, phoneid, (sysarg_t) &data,	137	callres = __SYSCALL3(SYS_IPC_CALL_SYNC, phoneid, (sysarg_t) &data,
138	(sysarg_t) &data);	138	(sysarg_t) &data);
139	if (callres)	139	if (callres)
140	return callres;	140	return callres;
141		141
142	if (result1)	142	if (result1)
143	*result1 = IPC_GET_ARG1(data);	143	*result1 = IPC_GET_ARG1(data);
144	if (result2)	144	if (result2)
145	*result2 = IPC_GET_ARG2(data);	145	*result2 = IPC_GET_ARG2(data);
146	if (result3)	146	if (result3)
147	*result3 = IPC_GET_ARG3(data);	147	*result3 = IPC_GET_ARG3(data);
148	return IPC_GET_RETVAL(data);	148	return IPC_GET_RETVAL(data);
149	}	149	}
150		150
151	/** Syscall to send asynchronous message.	151	/** Syscall to send asynchronous message.
152	*	152	*
153	* @param phoneid Phone handle for the call.	153	* @param phoneid Phone handle for the call.
154	* @param data Call data with the request.	154	* @param data Call data with the request.
155	*	155	*
156	* @return Hash of the call or an error code.	156	* @return Hash of the call or an error code.
157	*/	157	*/
158	static ipc_callid_t _ipc_call_async(int phoneid, ipc_call_t *data)	158	static ipc_callid_t _ipc_call_async(int phoneid, ipc_call_t *data)
159	{	159	{
160	return __SYSCALL2(SYS_IPC_CALL_ASYNC, phoneid, (sysarg_t) data);	160	return __SYSCALL2(SYS_IPC_CALL_ASYNC, phoneid, (sysarg_t) data);
161	}	161	}
162		162
163	/** Prolog to ipc_call_async_*() functions.	163	/** Prolog to ipc_call_async_*() functions.
164	*	164	*
165	* @param private Argument for the answer/error callback.	165	* @param private Argument for the answer/error callback.
166	* @param callback Answer/error callback.	166	* @param callback Answer/error callback.
167	*	167	*
168	* @return New, partially initialized async_call structure or NULL.	168	* @return New, partially initialized async_call structure or NULL.
169	*/	169	*/
170	static inline async_call_t ipc_prepare_async(void private,	170	static inline async_call_t ipc_prepare_async(void private,
171	ipc_async_callback_t callback)	171	ipc_async_callback_t callback)
172	{	172	{
173	async_call_t *call;	173	async_call_t *call;
174		174
175	call = malloc(sizeof(*call));	175	call = malloc(sizeof(*call));
176	if (!call) {	176	if (!call) {
177	if (callback)	177	if (callback)
178	callback(private, ENOMEM, NULL);	178	callback(private, ENOMEM, NULL);
179	return NULL;	179	return NULL;
180	}	180	}
181	call->callback = callback;	181	call->callback = callback;
182	call->private = private;	182	call->private = private;
183		183
184	return call;	184	return call;
185	}	185	}
186		186
187	/** Epilogue of ipc_call_async_*() functions.	187	/** Epilogue of ipc_call_async_*() functions.
188	*	188	*
189	* @param callid Value returned by the SYS_IPC_CALL_ASYNC_* syscall.	189	* @param callid Value returned by the SYS_IPC_CALL_ASYNC_* syscall.
190	* @param phoneid Phone handle through which the call was made.	190	* @param phoneid Phone handle through which the call was made.
191	* @param call async_call structure returned by ipc_prepare_async().	191	* @param call async_call structure returned by ipc_prepare_async().
192	* @param can_preempt If non-zero, the current pseudo thread can be preempted	192	* @param can_preempt If non-zero, the current fibril can be preempted in this
193	* in this call.	193	* call.
194	*/	194	*/
195	static inline void ipc_finish_async(ipc_callid_t callid, int phoneid,	195	static inline void ipc_finish_async(ipc_callid_t callid, int phoneid,
196	async_call_t *call, int can_preempt)	196	async_call_t *call, int can_preempt)
197	{	197	{
198	if (!call) { /* Nothing to do regardless if failed or not */	198	if (!call) { /* Nothing to do regardless if failed or not */
199	futex_up(&ipc_futex);	199	futex_up(&ipc_futex);
200	return;	200	return;
201	}	201	}
202		202
203	if (callid == IPC_CALLRET_FATAL) {	203	if (callid == IPC_CALLRET_FATAL) {
204	futex_up(&ipc_futex);	204	futex_up(&ipc_futex);
205	/* Call asynchronous handler with error code */	205	/* Call asynchronous handler with error code */
206	if (call->callback)	206	if (call->callback)
207	call->callback(call->private, ENOENT, NULL);	207	call->callback(call->private, ENOENT, NULL);
208	free(call);	208	free(call);
209	return;	209	return;
210	}	210	}
211		211
212	if (callid == IPC_CALLRET_TEMPORARY) {	212	if (callid == IPC_CALLRET_TEMPORARY) {
213	futex_up(&ipc_futex);	213	futex_up(&ipc_futex);
214		214
215	call->u.msg.phoneid = phoneid;	215	call->u.msg.phoneid = phoneid;
216		216
217	futex_down(&async_futex);	217	futex_down(&async_futex);
218	list_append(&call->list, &queued_calls);	218	list_append(&call->list, &queued_calls);
219		219
220	if (can_preempt) {	220	if (can_preempt) {
221	call->fid = fibril_get_id();	221	call->fid = fibril_get_id();
222	fibril_schedule_next_adv(FIBRIL_TO_MANAGER);	222	fibril_schedule_next_adv(FIBRIL_TO_MANAGER);
223	/* Async futex unlocked by previous call */	223	/* Async futex unlocked by previous call */
224	} else {	224	} else {
225	call->fid = 0;	225	call->fid = 0;
226	futex_up(&async_futex);	226	futex_up(&async_futex);
227	}	227	}
228	return;	228	return;
229	}	229	}
230	call->u.callid = callid;	230	call->u.callid = callid;
231	/* Add call to the list of dispatched calls */	231	/* Add call to the list of dispatched calls */
232	list_append(&call->list, &dispatched_calls);	232	list_append(&call->list, &dispatched_calls);
233	futex_up(&ipc_futex);	233	futex_up(&ipc_futex);
234		234
235	}	235	}
236		236
237	/** Make a fast asynchronous call.	237	/** Make a fast asynchronous call.
238	*	238	*
239	* This function can only handle two arguments of payload. It is, however,	239	* This function can only handle two arguments of payload. It is, however,
240	* faster than the more generic ipc_call_async_3().	240	* faster than the more generic ipc_call_async_3().
241	*	241	*
242	* Note that this function is a void function.	242	* Note that this function is a void function.
243	* During normal opertation, answering this call will trigger the callback.	243	* During normal opertation, answering this call will trigger the callback.
244	* In case of fatal error, call the callback handler with the proper error code.	244	* In case of fatal error, call the callback handler with the proper error code.
245	* If the call cannot be temporarily made, queue it.	245	* If the call cannot be temporarily made, queue it.
246	*	246	*
247	* @param phoneid Phone handle for the call.	247	* @param phoneid Phone handle for the call.
248	* @param method Requested method.	248	* @param method Requested method.
249	* @param arg1 Service-defined payload argument.	249	* @param arg1 Service-defined payload argument.
250	* @param arg2 Service-defined payload argument.	250	* @param arg2 Service-defined payload argument.
251	* @param private Argument to be passed to the answer/error callback.	251	* @param private Argument to be passed to the answer/error callback.
252	* @param callback Answer or error callback.	252	* @param callback Answer or error callback.
253	* @param can_preempt If non-zero, the current pseudo thread will be preempted	253	* @param can_preempt If non-zero, the current fibril will be preempted in
254	* in case the kernel temporarily refuses to accept more	254	* case the kernel temporarily refuses to accept more
255	* asynchronous calls.	255	* asynchronous calls.
256	*/	256	*/
257	void ipc_call_async_2(int phoneid, ipcarg_t method, ipcarg_t arg1,	257	void ipc_call_async_2(int phoneid, ipcarg_t method, ipcarg_t arg1,
258	ipcarg_t arg2, void *private, ipc_async_callback_t callback,	258	ipcarg_t arg2, void *private, ipc_async_callback_t callback,
259	int can_preempt)	259	int can_preempt)
260	{	260	{
261	async_call_t *call = NULL;	261	async_call_t *call = NULL;
262	ipc_callid_t callid;	262	ipc_callid_t callid;
263		263
264	if (callback) {	264	if (callback) {
265	call = ipc_prepare_async(private, callback);	265	call = ipc_prepare_async(private, callback);
266	if (!call)	266	if (!call)
267	return;	267	return;
268	}	268	}
269		269
270	/*	270	/*
271	* We need to make sure that we get callid before another thread	271	* We need to make sure that we get callid before another thread
272	* accesses the queue again.	272	* accesses the queue again.
273	*/	273	*/
274	futex_down(&ipc_futex);	274	futex_down(&ipc_futex);
275	callid = __SYSCALL4(SYS_IPC_CALL_ASYNC_FAST, phoneid, method, arg1,	275	callid = __SYSCALL4(SYS_IPC_CALL_ASYNC_FAST, phoneid, method, arg1,
276	arg2);	276	arg2);
277		277
278	if (callid == IPC_CALLRET_TEMPORARY) {	278	if (callid == IPC_CALLRET_TEMPORARY) {
279	if (!call) {	279	if (!call) {
280	call = ipc_prepare_async(private, callback);	280	call = ipc_prepare_async(private, callback);
281	if (!call)	281	if (!call)
282	return;	282	return;
283	}	283	}
284	IPC_SET_METHOD(call->u.msg.data, method);	284	IPC_SET_METHOD(call->u.msg.data, method);
285	IPC_SET_ARG1(call->u.msg.data, arg1);	285	IPC_SET_ARG1(call->u.msg.data, arg1);
286	IPC_SET_ARG2(call->u.msg.data, arg2);	286	IPC_SET_ARG2(call->u.msg.data, arg2);
287	}	287	}
288	ipc_finish_async(callid, phoneid, call, can_preempt);	288	ipc_finish_async(callid, phoneid, call, can_preempt);
289	}	289	}
290		290
291	/** Make an asynchronous call transmitting the entire payload.	291	/** Make an asynchronous call transmitting the entire payload.
292	*	292	*
293	* Note that this function is a void function.	293	* Note that this function is a void function.
294	* During normal opertation, answering this call will trigger the callback.	294	* During normal opertation, answering this call will trigger the callback.
295	* In case of fatal error, call the callback handler with the proper error code.	295	* In case of fatal error, call the callback handler with the proper error code.
296	* If the call cannot be temporarily made, queue it.	296	* If the call cannot be temporarily made, queue it.
297	*	297	*
298	* @param phoneid Phone handle for the call.	298	* @param phoneid Phone handle for the call.
299	* @param method Requested method.	299	* @param method Requested method.
300	* @param arg1 Service-defined payload argument.	300	* @param arg1 Service-defined payload argument.
301	* @param arg2 Service-defined payload argument.	301	* @param arg2 Service-defined payload argument.
302	* @param arg3 Service-defined payload argument.	302	* @param arg3 Service-defined payload argument.
303	* @param private Argument to be passed to the answer/error callback.	303	* @param private Argument to be passed to the answer/error callback.
304	* @param callback Answer or error callback.	304	* @param callback Answer or error callback.
305	* @param can_preempt If non-zero, the current pseudo thread will be preempted	305	* @param can_preempt If non-zero, the current fibril will be preempted in
306	* in case the kernel temporarily refuses to accept more	306	* case the kernel temporarily refuses to accept more
307	* asynchronous calls.	307	* asynchronous calls.
308	*	308	*
309	*/	309	*/
310	void ipc_call_async_3(int phoneid, ipcarg_t method, ipcarg_t arg1,	310	void ipc_call_async_3(int phoneid, ipcarg_t method, ipcarg_t arg1,
311	ipcarg_t arg2, ipcarg_t arg3, void *private, ipc_async_callback_t callback,	311	ipcarg_t arg2, ipcarg_t arg3, void *private, ipc_async_callback_t callback,
312	int can_preempt)	312	int can_preempt)
313	{	313	{
314	async_call_t *call;	314	async_call_t *call;
315	ipc_callid_t callid;	315	ipc_callid_t callid;
316		316
317	call = ipc_prepare_async(private, callback);	317	call = ipc_prepare_async(private, callback);
318	if (!call)	318	if (!call)
319	return;	319	return;
320		320
321	IPC_SET_METHOD(call->u.msg.data, method);	321	IPC_SET_METHOD(call->u.msg.data, method);
322	IPC_SET_ARG1(call->u.msg.data, arg1);	322	IPC_SET_ARG1(call->u.msg.data, arg1);
323	IPC_SET_ARG2(call->u.msg.data, arg2);	323	IPC_SET_ARG2(call->u.msg.data, arg2);
324	IPC_SET_ARG3(call->u.msg.data, arg3);	324	IPC_SET_ARG3(call->u.msg.data, arg3);
325	/*	325	/*
326	* We need to make sure that we get callid before another thread accesses	326	* We need to make sure that we get callid before another thread accesses
327	* the queue again.	327	* the queue again.
328	*/	328	*/
329	futex_down(&ipc_futex);	329	futex_down(&ipc_futex);
330	callid = _ipc_call_async(phoneid, &call->u.msg.data);	330	callid = _ipc_call_async(phoneid, &call->u.msg.data);
331		331
332	ipc_finish_async(callid, phoneid, call, can_preempt);	332	ipc_finish_async(callid, phoneid, call, can_preempt);
333	}	333	}
334		334
335		335
336	/** Answer a received call - fast version.	336	/** Answer a received call - fast version.
337	*	337	*
338	* The fast answer makes use of passing retval and first two arguments in	338	* The fast answer makes use of passing retval and first two arguments in
339	* registers. If you need to return more, use the ipc_answer() instead.	339	* registers. If you need to return more, use the ipc_answer() instead.
340	*	340	*
341	* @param callid Hash of the call being answered.	341	* @param callid Hash of the call being answered.
342	* @param retval Return value.	342	* @param retval Return value.
343	* @param arg1 First return argument.	343	* @param arg1 First return argument.
344	* @param arg2 Second return argument.	344	* @param arg2 Second return argument.
345	*	345	*
346	* @return Zero on success or a value from @ref errno.h on failure.	346	* @return Zero on success or a value from @ref errno.h on failure.
347	*/	347	*/
348	ipcarg_t ipc_answer_fast(ipc_callid_t callid, ipcarg_t retval, ipcarg_t arg1,	348	ipcarg_t ipc_answer_fast(ipc_callid_t callid, ipcarg_t retval, ipcarg_t arg1,
349	ipcarg_t arg2)	349	ipcarg_t arg2)
350	{	350	{
351	return __SYSCALL4(SYS_IPC_ANSWER_FAST, callid, retval, arg1, arg2);	351	return __SYSCALL4(SYS_IPC_ANSWER_FAST, callid, retval, arg1, arg2);
352	}	352	}
353		353
354	/** Answer a received call - full version.	354	/** Answer a received call - full version.
355	*	355	*
356	* @param callid Hash of the call being answered.	356	* @param callid Hash of the call being answered.
357	* @param call Call structure with the answer.	357	* @param call Call structure with the answer.
358	* Must be already initialized by the responder.	358	* Must be already initialized by the responder.
359	*	359	*
360	* @return Zero on success or a value from @ref errno.h on failure.	360	* @return Zero on success or a value from @ref errno.h on failure.
361	*/	361	*/
362	ipcarg_t ipc_answer(ipc_callid_t callid, ipc_call_t *call)	362	ipcarg_t ipc_answer(ipc_callid_t callid, ipc_call_t *call)
363	{	363	{
364	return __SYSCALL2(SYS_IPC_ANSWER, callid, (sysarg_t) call);	364	return __SYSCALL2(SYS_IPC_ANSWER, callid, (sysarg_t) call);
365	}	365	}
366		366
367		367
368	/** Try to dispatch queued calls from the async queue. */	368	/** Try to dispatch queued calls from the async queue. */
369	static void try_dispatch_queued_calls(void)	369	static void try_dispatch_queued_calls(void)
370	{	370	{
371	async_call_t *call;	371	async_call_t *call;
372	ipc_callid_t callid;	372	ipc_callid_t callid;
373		373
374	/** @todo	374	/** @todo
375	* Integrate intelligently ipc_futex, so that it is locked during	375	* Integrate intelligently ipc_futex, so that it is locked during
376	* ipc_call_async_*(), until it is added to dispatched_calls.	376	* ipc_call_async_*(), until it is added to dispatched_calls.
377	*/	377	*/
378	futex_down(&async_futex);	378	futex_down(&async_futex);
379	while (!list_empty(&queued_calls)) {	379	while (!list_empty(&queued_calls)) {
380	call = list_get_instance(queued_calls.next, async_call_t, list);	380	call = list_get_instance(queued_calls.next, async_call_t, list);
381	callid = _ipc_call_async(call->u.msg.phoneid, &call->u.msg.data);	381	callid = _ipc_call_async(call->u.msg.phoneid, &call->u.msg.data);
382	if (callid == IPC_CALLRET_TEMPORARY) {	382	if (callid == IPC_CALLRET_TEMPORARY) {
383	break;	383	break;
384	}	384	}
385	list_remove(&call->list);	385	list_remove(&call->list);
386		386
387	futex_up(&async_futex);	387	futex_up(&async_futex);
388	if (call->fid)	388	if (call->fid)
389	fibril_add_ready(call->fid);	389	fibril_add_ready(call->fid);
390		390
391	if (callid == IPC_CALLRET_FATAL) {	391	if (callid == IPC_CALLRET_FATAL) {
392	if (call->callback)	392	if (call->callback)
393	call->callback(call->private, ENOENT, NULL);	393	call->callback(call->private, ENOENT, NULL);
394	free(call);	394	free(call);
395	} else {	395	} else {
396	call->u.callid = callid;	396	call->u.callid = callid;
397	futex_down(&ipc_futex);	397	futex_down(&ipc_futex);
398	list_append(&call->list, &dispatched_calls);	398	list_append(&call->list, &dispatched_calls);
399	futex_up(&ipc_futex);	399	futex_up(&ipc_futex);
400	}	400	}
401	futex_down(&async_futex);	401	futex_down(&async_futex);
402	}	402	}
403	futex_up(&async_futex);	403	futex_up(&async_futex);
404	}	404	}
405		405
406	/** Handle a received answer.	406	/** Handle a received answer.
407	*	407	*
408	* Find the hash of the answer and call the answer callback.	408	* Find the hash of the answer and call the answer callback.
409	*	409	*
410	* @todo Make it use hash table.	410	* @todo Make it use hash table.
411	*	411	*
412	* @param callid Hash of the received answer.	412	* @param callid Hash of the received answer.
413	* The answer has the same hash as the request OR'ed with	413	* The answer has the same hash as the request OR'ed with
414	* the IPC_CALLID_ANSWERED bit.	414	* the IPC_CALLID_ANSWERED bit.
415	* @param data Call data of the answer.	415	* @param data Call data of the answer.
416	*/	416	*/
417	static void handle_answer(ipc_callid_t callid, ipc_call_t *data)	417	static void handle_answer(ipc_callid_t callid, ipc_call_t *data)
418	{	418	{
419	link_t *item;	419	link_t *item;
420	async_call_t *call;	420	async_call_t *call;
421		421
422	callid &= ~IPC_CALLID_ANSWERED;	422	callid &= ~IPC_CALLID_ANSWERED;
423		423
424	futex_down(&ipc_futex);	424	futex_down(&ipc_futex);
425	for (item = dispatched_calls.next; item != &dispatched_calls;	425	for (item = dispatched_calls.next; item != &dispatched_calls;
426	item = item->next) {	426	item = item->next) {
427	call = list_get_instance(item, async_call_t, list);	427	call = list_get_instance(item, async_call_t, list);
428	if (call->u.callid == callid) {	428	if (call->u.callid == callid) {
429	list_remove(&call->list);	429	list_remove(&call->list);
430	futex_up(&ipc_futex);	430	futex_up(&ipc_futex);
431	if (call->callback)	431	if (call->callback)
432	call->callback(call->private,	432	call->callback(call->private,
433	IPC_GET_RETVAL(*data), data);	433	IPC_GET_RETVAL(*data), data);
434	free(call);	434	free(call);
435	return;	435	return;
436	}	436	}
437	}	437	}
438	futex_up(&ipc_futex);	438	futex_up(&ipc_futex);
439	}	439	}
440		440
441		441
442	/** Wait for a first call to come.	442	/** Wait for a first call to come.
443	*	443	*
444	* @param call Storage where the incoming call data will be stored.	444	* @param call Storage where the incoming call data will be stored.
445	* @param usec Timeout in microseconds	445	* @param usec Timeout in microseconds
446	* @param flags Flags passed to SYS_IPC_WAIT (blocking, nonblocking).	446	* @param flags Flags passed to SYS_IPC_WAIT (blocking, nonblocking).
447	*	447	*
448	* @return Hash of the call. Note that certain bits have special	448	* @return Hash of the call. Note that certain bits have special
449	* meaning. IPC_CALLID_ANSWERED will be set in an answer	449	* meaning. IPC_CALLID_ANSWERED will be set in an answer
450	* and IPC_CALLID_NOTIFICATION is used for notifications.	450	* and IPC_CALLID_NOTIFICATION is used for notifications.
451	*	451	*
452	*/	452	*/
453	ipc_callid_t ipc_wait_cycle(ipc_call_t *call, uint32_t usec, int flags)	453	ipc_callid_t ipc_wait_cycle(ipc_call_t *call, uint32_t usec, int flags)
454	{	454	{
455	ipc_callid_t callid;	455	ipc_callid_t callid;
456		456
457	callid = __SYSCALL3(SYS_IPC_WAIT, (sysarg_t) call, usec, flags);	457	callid = __SYSCALL3(SYS_IPC_WAIT, (sysarg_t) call, usec, flags);
458	/* Handle received answers */	458	/* Handle received answers */
459	if (callid & IPC_CALLID_ANSWERED) {	459	if (callid & IPC_CALLID_ANSWERED) {
460	handle_answer(callid, call);	460	handle_answer(callid, call);
461	try_dispatch_queued_calls();	461	try_dispatch_queued_calls();
462	}	462	}
463		463
464	return callid;	464	return callid;
465	}	465	}
466		466
467	/** Wait some time for an IPC call.	467	/** Wait some time for an IPC call.
468	*	468	*
469	* The call will return after an answer is received.	469	* The call will return after an answer is received.
470	*	470	*
471	* @param call Storage where the incoming call data will be stored.	471	* @param call Storage where the incoming call data will be stored.
472	* @param usec Timeout in microseconds.	472	* @param usec Timeout in microseconds.
473	*	473	*
474	* @return Hash of the answer.	474	* @return Hash of the answer.
475	*/	475	*/
476	ipc_callid_t ipc_wait_for_call_timeout(ipc_call_t *call, uint32_t usec)	476	ipc_callid_t ipc_wait_for_call_timeout(ipc_call_t *call, uint32_t usec)
477	{	477	{
478	ipc_callid_t callid;	478	ipc_callid_t callid;
479		479
480	do {	480	do {
481	callid = ipc_wait_cycle(call, usec, SYNCH_FLAGS_NONE);	481	callid = ipc_wait_cycle(call, usec, SYNCH_FLAGS_NONE);
482	} while (callid & IPC_CALLID_ANSWERED);	482	} while (callid & IPC_CALLID_ANSWERED);
483		483
484	return callid;	484	return callid;
485	}	485	}
486		486
487	/** Check if there is an IPC call waiting to be picked up.	487	/** Check if there is an IPC call waiting to be picked up.
488	*	488	*
489	* @param call Storage where the incoming call will be stored.	489	* @param call Storage where the incoming call will be stored.
490	* @return Hash of the answer.	490	* @return Hash of the answer.
491	*/	491	*/
492	ipc_callid_t ipc_trywait_for_call(ipc_call_t *call)	492	ipc_callid_t ipc_trywait_for_call(ipc_call_t *call)
493	{	493	{
494	ipc_callid_t callid;	494	ipc_callid_t callid;
495		495
496	do {	496	do {
497	callid = ipc_wait_cycle(call, SYNCH_NO_TIMEOUT,	497	callid = ipc_wait_cycle(call, SYNCH_NO_TIMEOUT,
498	SYNCH_FLAGS_NON_BLOCKING);	498	SYNCH_FLAGS_NON_BLOCKING);
499	} while (callid & IPC_CALLID_ANSWERED);	499	} while (callid & IPC_CALLID_ANSWERED);
500		500

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(root)/branches/dd/uspace/lib/libc/generic/ipc.c @ 4537 – Rev 2522 → 2530