WebSVN – HelenOS – Diff – /branches/sparc/kernel/generic/src/ipc/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 genericipc
 * @{
 */
/** @file
 */
 
/* Lock ordering
 *
 * First the answerbox, then the phone.
 */
 
#include <synch/synch.h>
#include <synch/spinlock.h>
#include <synch/mutex.h>
#include <synch/waitq.h>
#include <synch/synch.h>
#include <ipc/ipc.h>
#include <ipc/kbox.h>
#include <errno.h>
#include <mm/slab.h>
#include <arch.h>
#include <arch/asm.h>
#include <proc/task.h>
#include <memstr.h>
#include <debug.h>
 
#include <print.h>
#include <console/console.h>
#include <proc/thread.h>
#include <arch/interrupt.h>
#include <ipc/irq.h>
 
/** Open channel that is assigned automatically to new tasks */
answerbox_t *ipc_phone_0 = NULL;
 
static slab_cache_t *ipc_call_slab;
 
/** Initialize a call structure.
 *
 * @param call      Call structure to be initialized.
 */
static void _ipc_call_init(call_t *call)
{
    memsetb(call, sizeof(*call), 0);
    call->callerbox = &TASK->answerbox;
    call->sender = TASK;
    call->buffer = NULL;
}
 
/** Allocate and initialize a call structure.
 *
 * The call is initialized, so that the reply will be directed to
 * TASK->answerbox.
 *
 * @param flags     Parameters for slab_alloc (e.g FRAME_ATOMIC).
 *
 * @return      If flags permit it, return NULL, or initialized kernel
 *          call structure.
 */
call_t *ipc_call_alloc(int flags)
{
    call_t *call;
 
    call = slab_alloc(ipc_call_slab, flags);
    if (call)
        _ipc_call_init(call);
 
    return call;
}
 
/** Initialize a statically allocated call structure.
 *
 * @param call      Statically allocated kernel call structure to be
 *          initialized.
 */
void ipc_call_static_init(call_t *call)
{
    _ipc_call_init(call);
    call->flags |= IPC_CALL_STATIC_ALLOC;
}
 
/** Deallocate a call structure.
 *
 * @param call      Call structure to be freed.
 */
void ipc_call_free(call_t *call)
{
    ASSERT(!(call->flags & IPC_CALL_STATIC_ALLOC));
    /* Check to see if we have data in the IPC_M_DATA_SEND buffer. */
    if (call->buffer)
        free(call->buffer);
    slab_free(ipc_call_slab, call);
}
 
/** Initialize an answerbox structure.
 *
 * @param box       Answerbox structure to be initialized.
 * @param task      Task to which the answerbox belongs.
 */
void ipc_answerbox_init(answerbox_t *box, task_t *task)
{
    spinlock_initialize(&box->lock, "ipc_box_lock");
    spinlock_initialize(&box->irq_lock, "ipc_box_irqlock");
    waitq_initialize(&box->wq);
    list_initialize(&box->connected_phones);
    list_initialize(&box->calls);
    list_initialize(&box->dispatched_calls);
    list_initialize(&box->answers);
    list_initialize(&box->irq_notifs);
    list_initialize(&box->irq_head);
    box->task = task;
}
 
/** Connect a phone to an answerbox.
 *
 * @param phone     Initialized phone structure.
 * @param box       Initialized answerbox structure.
 */
void ipc_phone_connect(phone_t *phone, answerbox_t *box)
{
    mutex_lock(&phone->lock);
 
    phone->state = IPC_PHONE_CONNECTED;
    phone->callee = box;
 
    spinlock_lock(&box->lock);
    list_append(&phone->link, &box->connected_phones);
    spinlock_unlock(&box->lock);
 
    mutex_unlock(&phone->lock);
}
 
/** Initialize a phone structure.
 *
 * @param phone     Phone structure to be initialized.
 */
void ipc_phone_init(phone_t *phone)
{
    mutex_initialize(&phone->lock, MUTEX_PASSIVE);
    phone->callee = NULL;
    phone->state = IPC_PHONE_FREE;
    atomic_set(&phone->active_calls, 0);
}
 
/** Helper function to facilitate synchronous calls.
 *
 * @param phone     Destination kernel phone structure.
 * @param request   Call structure with request.
 *
 * @return      EOK on success or EINTR if the sleep was interrupted.
 */
int ipc_call_sync(phone_t *phone, call_t *request)
{
    answerbox_t sync_box;
 
    ipc_answerbox_init(&sync_box, TASK);
 
    /* We will receive data in a special box. */
    request->callerbox = &sync_box;
 
    ipc_call(phone, request);
    if (!ipc_wait_for_call(&sync_box, SYNCH_NO_TIMEOUT,
        SYNCH_FLAGS_INTERRUPTIBLE))
        return EINTR;
    return EOK;
}
 
/** Answer a message which was not dispatched and is not listed in any queue.
 *
 * @param call      Call structure to be answered.
 */
static void _ipc_answer_free_call(call_t *call)
{
    answerbox_t *callerbox = call->callerbox;
 
    call->flags |= IPC_CALL_ANSWERED;
 
    if (call->flags & IPC_CALL_FORWARDED) {
        if (call->caller_phone) {
            /* Demasquerade the caller phone. */
            call->data.phone = call->caller_phone;
        }
    }
 
    spinlock_lock(&callerbox->lock);
    list_append(&call->link, &callerbox->answers);
    spinlock_unlock(&callerbox->lock);
    waitq_wakeup(&callerbox->wq, WAKEUP_FIRST);
}
 
/** Answer a message which is in a callee queue.
 *
 * @param box       Answerbox that is answering the message.
 * @param call      Modified request that is being sent back.
 */
void ipc_answer(answerbox_t *box, call_t *call)
{
    /* Remove from active box */
    spinlock_lock(&box->lock);
    list_remove(&call->link);
    spinlock_unlock(&box->lock);
    /* Send back answer */
    _ipc_answer_free_call(call);
}
 
/** Simulate sending back a message.
 *
 * Most errors are better handled by forming a normal backward
 * message and sending it as a normal answer.
 *
 * @param phone     Phone structure the call should appear to come from.
 * @param call      Call structure to be answered.
 * @param err       Return value to be used for the answer.
 */
void ipc_backsend_err(phone_t *phone, call_t *call, unative_t err)
{
    call->data.phone = phone;
    atomic_inc(&phone->active_calls);
    IPC_SET_RETVAL(call->data, err);
    _ipc_answer_free_call(call);
}
 
/** Unsafe unchecking version of ipc_call.
 *
 * @param phone     Phone structure the call comes from.
 * @param box       Destination answerbox structure.
 * @param call      Call structure with request.
 */
static void _ipc_call(phone_t *phone, answerbox_t *box, call_t *call)
{
    if (!(call->flags & IPC_CALL_FORWARDED)) {
        atomic_inc(&phone->active_calls);
        call->data.phone = phone;
    }
 
    spinlock_lock(&box->lock);
    list_append(&call->link, &box->calls);
    spinlock_unlock(&box->lock);
    waitq_wakeup(&box->wq, WAKEUP_FIRST);
}
 
/** Send an asynchronous request using a phone to an answerbox.
 *
 * @param phone     Phone structure the call comes from and which is
 *          connected to the destination answerbox.
 * @param call      Call structure with request.
 *
 * @return      Return 0 on success, ENOENT on error.
 */
int ipc_call(phone_t *phone, call_t *call)
{
    answerbox_t *box;
 
    mutex_lock(&phone->lock);
    if (phone->state != IPC_PHONE_CONNECTED) {
        mutex_unlock(&phone->lock);
        if (call->flags & IPC_CALL_FORWARDED) {
            IPC_SET_RETVAL(call->data, EFORWARD);
            _ipc_answer_free_call(call);
        } else {
            if (phone->state == IPC_PHONE_HUNGUP)
                ipc_backsend_err(phone, call, EHANGUP);
            else
                ipc_backsend_err(phone, call, ENOENT);
        }
        return ENOENT;
    }
    box = phone->callee;
    _ipc_call(phone, box, call);
   
    mutex_unlock(&phone->lock);
    return 0;
}
 
/** Disconnect phone from answerbox.
 *
 * This call leaves the phone in the HUNGUP state. The change to 'free' is done
 * lazily later.
 *
 * @param phone     Phone structure to be hung up.
 *              
 * @return      Return 0 if the phone is disconnected.
 *          Return -1 if the phone was already disconnected.
 */
int ipc_phone_hangup(phone_t *phone)
{
    answerbox_t *box;
    call_t *call;
   
    mutex_lock(&phone->lock);
    if (phone->state == IPC_PHONE_FREE ||
        phone->state == IPC_PHONE_HUNGUP ||
        phone->state == IPC_PHONE_CONNECTING) {
        mutex_unlock(&phone->lock);
        return -1;
    }
    box = phone->callee;
    if (phone->state != IPC_PHONE_SLAMMED) {
        /* Remove myself from answerbox */
        spinlock_lock(&box->lock);
        list_remove(&phone->link);
        spinlock_unlock(&box->lock);
 
        if (phone->state != IPC_PHONE_SLAMMED) {
            call = ipc_call_alloc(0);
            IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);
            call->flags |= IPC_CALL_DISCARD_ANSWER;
            _ipc_call(phone, box, call);
        }
    }
 
    phone->state = IPC_PHONE_HUNGUP;
    mutex_unlock(&phone->lock);
 
    return 0;
}
 
/** Forwards call from one answerbox to another one.
 *
 * @param call      Call structure to be redirected.
 * @param newphone  Phone structure to target answerbox.
 * @param oldbox    Old answerbox structure.
 * @param mode      Flags that specify mode of the forward operation.
 *
 * @return      Return 0 if forwarding succeeded or an error code if
 *          there was error.
 *
 * The return value serves only as an information for the forwarder,
 * the original caller is notified automatically with EFORWARD.
 */
int ipc_forward(call_t *call, phone_t *newphone, answerbox_t *oldbox, int mode)
{
    spinlock_lock(&oldbox->lock);
    list_remove(&call->link);
    spinlock_unlock(&oldbox->lock);
 
    if (mode & IPC_FF_ROUTE_FROM_ME) {
        if (!call->caller_phone)
            call->caller_phone = call->data.phone;
        call->data.phone = newphone;
    }
 
    return ipc_call(newphone, call);
}
 
 
/** Wait for a phone call.
 *
 * @param box       Answerbox expecting the call.
 * @param usec      Timeout in microseconds. See documentation for
 *          waitq_sleep_timeout() for decription of its special
 *          meaning.
 * @param flags     Select mode of sleep operation. See documentation for
 *          waitq_sleep_timeout() for description of its special
 *          meaning.
 * @return      Recived call structure or NULL.
 *
 * To distinguish between a call and an answer, have a look at call->flags.
 */
call_t *ipc_wait_for_call(answerbox_t *box, uint32_t usec, int flags)
{
    call_t *request;
    ipl_t ipl;
    int rc;
 
restart:
    rc = waitq_sleep_timeout(&box->wq, usec, flags);
    if (SYNCH_FAILED(rc))
        return NULL;
   
    spinlock_lock(&box->lock);
    if (!list_empty(&box->irq_notifs)) {
        ipl = interrupts_disable();
        spinlock_lock(&box->irq_lock);
 
        request = list_get_instance(box->irq_notifs.next, call_t, link);
        list_remove(&request->link);
 
        spinlock_unlock(&box->irq_lock);
        interrupts_restore(ipl);
    } else if (!list_empty(&box->answers)) {
        /* Handle asynchronous answers */
        request = list_get_instance(box->answers.next, call_t, link);
        list_remove(&request->link);
        atomic_dec(&request->data.phone->active_calls);
    } else if (!list_empty(&box->calls)) {
        /* Handle requests */
        request = list_get_instance(box->calls.next, call_t, link);
        list_remove(&request->link);
        /* Append request to dispatch queue */
        list_append(&request->link, &box->dispatched_calls);
    } else {
        /* This can happen regularly after ipc_cleanup */
        spinlock_unlock(&box->lock);
        goto restart;
    }
    spinlock_unlock(&box->lock);
    return request;
}
 
/** Answer all calls from list with EHANGUP answer.
 *
 * @param lst       Head of the list to be cleaned up.
 */
void ipc_cleanup_call_list(link_t *lst)
{
    call_t *call;
 
    while (!list_empty(lst)) {
        call = list_get_instance(lst->next, call_t, link);
        if (call->buffer)
            free(call->buffer);
        list_remove(&call->link);
 
        IPC_SET_RETVAL(call->data, EHANGUP);
        _ipc_answer_free_call(call);
    }
}
 
/** Disconnects all phones connected to an answerbox.
 *
 * @param box       Answerbox to disconnect phones from.
 * @param notify_box    If true, the answerbox will get a hangup message for
 *          each disconnected phone.
 */
void ipc_answerbox_slam_phones(answerbox_t *box, bool notify_box)
{
    phone_t *phone;
    DEADLOCK_PROBE_INIT(p_phonelck);
    ipl_t ipl;
    call_t *call;
 
    call = notify_box ? ipc_call_alloc(0) : NULL;
 
    /* Disconnect all phones connected to our answerbox */
restart_phones:
    ipl = interrupts_disable();
    spinlock_lock(&box->lock);
    while (!list_empty(&box->connected_phones)) {
        phone = list_get_instance(box->connected_phones.next,
            phone_t, link);
        if (SYNCH_FAILED(mutex_trylock(&phone->lock))) {
            spinlock_unlock(&box->lock);
            interrupts_restore(ipl);
            DEADLOCK_PROBE(p_phonelck, DEADLOCK_THRESHOLD);
            goto restart_phones;
        }
       
        /* Disconnect phone */
        ASSERT(phone->state == IPC_PHONE_CONNECTED);
 
        list_remove(&phone->link);
        phone->state = IPC_PHONE_SLAMMED;
 
        if (notify_box) {
            mutex_unlock(&phone->lock);
            spinlock_unlock(&box->lock);
            interrupts_restore(ipl);
 
            /*
             * Send one message to the answerbox for each
             * phone. Used to make sure the kbox thread
             * wakes up after the last phone has been
             * disconnected.
             */
            IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);
            call->flags |= IPC_CALL_DISCARD_ANSWER;
            _ipc_call(phone, box, call);
 
            /* Allocate another call in advance */
            call = ipc_call_alloc(0);
 
            /* Must start again */
            goto restart_phones;
        }
 
        mutex_unlock(&phone->lock);
    }
 
    spinlock_unlock(&box->lock);
    interrupts_restore(ipl);
 
    /* Free unused call */
    if (call)
        ipc_call_free(call);
}
 
/** Cleans up all IPC communication of the current task.
 *
 * Note: ipc_hangup sets returning answerbox to TASK->answerbox, you
 * have to change it as well if you want to cleanup other tasks than TASK.
 */
void ipc_cleanup(void)
{
    int i;
    call_t *call;
 
    /* Disconnect all our phones ('ipc_phone_hangup') */
    for (i = 0; i < IPC_MAX_PHONES; i++)
        ipc_phone_hangup(&TASK->phones[i]);
 
    /* Disconnect all connected irqs */
    ipc_irq_cleanup(&TASK->answerbox);
 
    /* Disconnect all phones connected to our regular answerbox */
    ipc_answerbox_slam_phones(&TASK->answerbox, false);
 
#ifdef CONFIG_UDEBUG
    /* Clean up kbox thread and communications */
    ipc_kbox_cleanup();
#endif
 
    /* Answer all messages in 'calls' and 'dispatched_calls' queues */
    spinlock_lock(&TASK->answerbox.lock);
    ipc_cleanup_call_list(&TASK->answerbox.dispatched_calls);
    ipc_cleanup_call_list(&TASK->answerbox.calls);
    spinlock_unlock(&TASK->answerbox.lock);
   
    /* Wait for all async answers to arrive */
    while (1) {
        /* Go through all phones, until all are FREE... */
        /* Locking not needed, no one else should modify
         * it, when we are in cleanup */
        for (i = 0; i < IPC_MAX_PHONES; i++) {
            if (TASK->phones[i].state == IPC_PHONE_HUNGUP &&
                atomic_get(&TASK->phones[i].active_calls) == 0)
                TASK->phones[i].state = IPC_PHONE_FREE;
           
            /* Just for sure, we might have had some
             * IPC_PHONE_CONNECTING phones */
            if (TASK->phones[i].state == IPC_PHONE_CONNECTED)
                ipc_phone_hangup(&TASK->phones[i]);
            /* If the hangup succeeded, it has sent a HANGUP
             * message, the IPC is now in HUNGUP state, we
             * wait for the reply to come */
           
            if (TASK->phones[i].state != IPC_PHONE_FREE)
                break;
        }
        /* Voila, got into cleanup */
        if (i == IPC_MAX_PHONES)
            break;
       
        call = ipc_wait_for_call(&TASK->answerbox, SYNCH_NO_TIMEOUT,
            SYNCH_FLAGS_NONE);
        ASSERT((call->flags & IPC_CALL_ANSWERED) ||
            (call->flags & IPC_CALL_NOTIF));
        ASSERT(!(call->flags & IPC_CALL_STATIC_ALLOC));
       
        /*
         * Record the receipt of this call in the current task's counter
         * of active calls. IPC_M_PHONE_HUNGUP calls do not contribute
         * to this counter so do not record answers to them either.
         */
        if (!(call->flags & IPC_CALL_DISCARD_ANSWER))
            atomic_dec(&TASK->active_calls);
        ipc_call_free(call);
    }
}
 
 
/** Initilize IPC subsystem */
void ipc_init(void)
{
    ipc_call_slab = slab_cache_create("ipc_call", sizeof(call_t), 0, NULL,
        NULL, 0);
}
 
 
/** List answerbox contents.
 *
 * @param taskid    Task ID.
 */
void ipc_print_task(task_id_t taskid)
{
    task_t *task;
    int i;
    call_t *call;
    link_t *tmp;
   
    spinlock_lock(&tasks_lock);
    task = task_find_by_id(taskid);
    if (task)
        spinlock_lock(&task->lock);
    spinlock_unlock(&tasks_lock);
    if (!task)
        return;
 
    /* Print opened phones & details */
    printf("PHONE:\n");
    for (i = 0; i < IPC_MAX_PHONES; i++) {
        if (SYNCH_FAILED(mutex_trylock(&task->phones[i].lock))) {
            printf("%d: mutex busy\n", i);
            continue;
        }
        if (task->phones[i].state != IPC_PHONE_FREE) {
            printf("%d: ", i);
            switch (task->phones[i].state) {
            case IPC_PHONE_CONNECTING:
                printf("connecting ");
                break;
            case IPC_PHONE_CONNECTED:
                printf("connected to: %p ",
                       task->phones[i].callee);
                break;
            case IPC_PHONE_SLAMMED:
                printf("slammed by: %p ",
                       task->phones[i].callee);
                break;
            case IPC_PHONE_HUNGUP:
                printf("hung up - was: %p ",
                       task->phones[i].callee);
                break;
            default:
                break;
            }
            printf("active: %ld\n",
                atomic_get(&task->phones[i].active_calls));
        }
        mutex_unlock(&task->phones[i].lock);
    }
 
 
    /* Print answerbox - calls */
    spinlock_lock(&task->answerbox.lock);
    printf("ABOX - CALLS:\n");
    for (tmp = task->answerbox.calls.next; tmp != &task->answerbox.calls;
        tmp = tmp->next) {
        call = list_get_instance(tmp, call_t, link);
        printf("Callid: %p Srctask:%" PRIu64 " M:%" PRIun
            " A1:%" PRIun " A2:%" PRIun " A3:%" PRIun
            " A4:%" PRIun " A5:%" PRIun " Flags:%x\n", call,
            call->sender->taskid,
            IPC_GET_METHOD(call->data), IPC_GET_ARG1(call->data),
            IPC_GET_ARG2(call->data), IPC_GET_ARG3(call->data),
            IPC_GET_ARG4(call->data), IPC_GET_ARG5(call->data),
            call->flags);
    }
    /* Print answerbox - calls */
    printf("ABOX - DISPATCHED CALLS:\n");
    for (tmp = task->answerbox.dispatched_calls.next;
        tmp != &task->answerbox.dispatched_calls;
        tmp = tmp->next) {
        call = list_get_instance(tmp, call_t, link);
        printf("Callid: %p Srctask:%" PRIu64 " M:%" PRIun
            " A1:%" PRIun " A2:%" PRIun " A3:%" PRIun
            " A4:%" PRIun " A5:%" PRIun " Flags:%x\n", call,
            call->sender->taskid,
            IPC_GET_METHOD(call->data), IPC_GET_ARG1(call->data),
            IPC_GET_ARG2(call->data), IPC_GET_ARG3(call->data),
            IPC_GET_ARG4(call->data), IPC_GET_ARG5(call->data),
            call->flags);
    }
    /* Print answerbox - calls */
    printf("ABOX - ANSWERS:\n");
    for (tmp = task->answerbox.answers.next;
        tmp != &task->answerbox.answers;
        tmp = tmp->next) {
        call = list_get_instance(tmp, call_t, link);
        printf("Callid:%p M:%" PRIun " A1:%" PRIun " A2:%" PRIun
            " A3:%" PRIun " A4:%" PRIun " A5:%" PRIun " Flags:%x\n",
            call, IPC_GET_METHOD(call->data), IPC_GET_ARG1(call->data),
            IPC_GET_ARG2(call->data), IPC_GET_ARG3(call->data),
            IPC_GET_ARG4(call->data), IPC_GET_ARG5(call->data),
            call->flags);
    }
 
    spinlock_unlock(&task->answerbox.lock);
    spinlock_unlock(&task->lock);
}
 
/** @}
 */
 

Rev 3492	Rev 3862
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 genericipc	29	/** @addtogroup genericipc
30	* @{	30	* @{
31	*/	31	*/
32	/** @file	32	/** @file
33	*/	33	*/
34		34
35	/* Lock ordering	35	/* Lock ordering
36	*	36	*
37	* First the answerbox, then the phone.	37	* First the answerbox, then the phone.
38	*/	38	*/
39		39
40	#include <synch/synch.h>	40	#include <synch/synch.h>
41	#include <synch/spinlock.h>	41	#include <synch/spinlock.h>
42	#include <synch/mutex.h>	42	#include <synch/mutex.h>
43	#include <synch/waitq.h>	43	#include <synch/waitq.h>
44	#include <synch/synch.h>	44	#include <synch/synch.h>
45	#include <ipc/ipc.h>	45	#include <ipc/ipc.h>
46	#include <ipc/kbox.h>	46	#include <ipc/kbox.h>
47	#include <errno.h>	47	#include <errno.h>
48	#include <mm/slab.h>	48	#include <mm/slab.h>
49	#include <arch.h>	49	#include <arch.h>
-		50	#include <arch/asm.h>
50	#include <proc/task.h>	51	#include <proc/task.h>
51	#include <memstr.h>	52	#include <memstr.h>
52	#include <debug.h>	53	#include <debug.h>
53		54
54	#include <print.h>	55	#include <print.h>
55	#include <console/console.h>	56	#include <console/console.h>
56	#include <proc/thread.h>	57	#include <proc/thread.h>
57	#include <arch/interrupt.h>	58	#include <arch/interrupt.h>
58	#include <ipc/irq.h>	59	#include <ipc/irq.h>
59		60
60	/** Open channel that is assigned automatically to new tasks */	61	/** Open channel that is assigned automatically to new tasks */
61	answerbox_t *ipc_phone_0 = NULL;	62	answerbox_t *ipc_phone_0 = NULL;
62		63
63	static slab_cache_t *ipc_call_slab;	64	static slab_cache_t *ipc_call_slab;
64		65
65	/** Initialize a call structure.	66	/** Initialize a call structure.
66	*	67	*
67	* @param call Call structure to be initialized.	68	* @param call Call structure to be initialized.
68	*/	69	*/
69	static void _ipc_call_init(call_t *call)	70	static void _ipc_call_init(call_t *call)
70	{	71	{
71	memsetb(call, sizeof(*call), 0);	72	memsetb(call, sizeof(*call), 0);
72	call->callerbox = &TASK->answerbox;	73	call->callerbox = &TASK->answerbox;
73	call->sender = TASK;	74	call->sender = TASK;
74	call->buffer = NULL;	75	call->buffer = NULL;
75	}	76	}
76		77
77	/** Allocate and initialize a call structure.	78	/** Allocate and initialize a call structure.
78	*	79	*
79	* The call is initialized, so that the reply will be directed to	80	* The call is initialized, so that the reply will be directed to
80	* TASK->answerbox.	81	* TASK->answerbox.
81	*	82	*
82	* @param flags Parameters for slab_alloc (e.g FRAME_ATOMIC).	83	* @param flags Parameters for slab_alloc (e.g FRAME_ATOMIC).
83	*	84	*
84	* @return If flags permit it, return NULL, or initialized kernel	85	* @return If flags permit it, return NULL, or initialized kernel
85	* call structure.	86	* call structure.
86	*/	87	*/
87	call_t *ipc_call_alloc(int flags)	88	call_t *ipc_call_alloc(int flags)
88	{	89	{
89	call_t *call;	90	call_t *call;
90		91
91	call = slab_alloc(ipc_call_slab, flags);	92	call = slab_alloc(ipc_call_slab, flags);
92	if (call)	93	if (call)
93	_ipc_call_init(call);	94	_ipc_call_init(call);
94		95
95	return call;	96	return call;
96	}	97	}
97		98
98	/** Initialize a statically allocated call structure.	99	/** Initialize a statically allocated call structure.
99	*	100	*
100	* @param call Statically allocated kernel call structure to be	101	* @param call Statically allocated kernel call structure to be
101	* initialized.	102	* initialized.
102	*/	103	*/
103	void ipc_call_static_init(call_t *call)	104	void ipc_call_static_init(call_t *call)
104	{	105	{
105	_ipc_call_init(call);	106	_ipc_call_init(call);
106	call->flags \|= IPC_CALL_STATIC_ALLOC;	107	call->flags \|= IPC_CALL_STATIC_ALLOC;
107	}	108	}
108		109
109	/** Deallocate a call structure.	110	/** Deallocate a call structure.
110	*	111	*
111	* @param call Call structure to be freed.	112	* @param call Call structure to be freed.
112	*/	113	*/
113	void ipc_call_free(call_t *call)	114	void ipc_call_free(call_t *call)
114	{	115	{
115	ASSERT(!(call->flags & IPC_CALL_STATIC_ALLOC));	116	ASSERT(!(call->flags & IPC_CALL_STATIC_ALLOC));
116	/* Check to see if we have data in the IPC_M_DATA_SEND buffer. */	117	/* Check to see if we have data in the IPC_M_DATA_SEND buffer. */
117	if (call->buffer)	118	if (call->buffer)
118	free(call->buffer);	119	free(call->buffer);
119	slab_free(ipc_call_slab, call);	120	slab_free(ipc_call_slab, call);
120	}	121	}
121		122
122	/** Initialize an answerbox structure.	123	/** Initialize an answerbox structure.
123	*	124	*
124	* @param box Answerbox structure to be initialized.	125	* @param box Answerbox structure to be initialized.
125	* @param task Task to which the answerbox belongs.	126	* @param task Task to which the answerbox belongs.
126	*/	127	*/
127	void ipc_answerbox_init(answerbox_t box, task_t task)	128	void ipc_answerbox_init(answerbox_t box, task_t task)
128	{	129	{
129	spinlock_initialize(&box->lock, "ipc_box_lock");	130	spinlock_initialize(&box->lock, "ipc_box_lock");
130	spinlock_initialize(&box->irq_lock, "ipc_box_irqlock");	131	spinlock_initialize(&box->irq_lock, "ipc_box_irqlock");
131	waitq_initialize(&box->wq);	132	waitq_initialize(&box->wq);
132	list_initialize(&box->connected_phones);	133	list_initialize(&box->connected_phones);
133	list_initialize(&box->calls);	134	list_initialize(&box->calls);
134	list_initialize(&box->dispatched_calls);	135	list_initialize(&box->dispatched_calls);
135	list_initialize(&box->answers);	136	list_initialize(&box->answers);
136	list_initialize(&box->irq_notifs);	137	list_initialize(&box->irq_notifs);
137	list_initialize(&box->irq_head);	138	list_initialize(&box->irq_head);
138	box->task = task;	139	box->task = task;
139	}	140	}
140		141
141	/** Connect a phone to an answerbox.	142	/** Connect a phone to an answerbox.
142	*	143	*
143	* @param phone Initialized phone structure.	144	* @param phone Initialized phone structure.
144	* @param box Initialized answerbox structure.	145	* @param box Initialized answerbox structure.
145	*/	146	*/
146	void ipc_phone_connect(phone_t phone, answerbox_t box)	147	void ipc_phone_connect(phone_t phone, answerbox_t box)
147	{	148	{
148	mutex_lock(&phone->lock);	149	mutex_lock(&phone->lock);
149		150
150	phone->state = IPC_PHONE_CONNECTED;	151	phone->state = IPC_PHONE_CONNECTED;
151	phone->callee = box;	152	phone->callee = box;
152		153
153	spinlock_lock(&box->lock);	154	spinlock_lock(&box->lock);
154	list_append(&phone->link, &box->connected_phones);	155	list_append(&phone->link, &box->connected_phones);
155	spinlock_unlock(&box->lock);	156	spinlock_unlock(&box->lock);
156		157
157	mutex_unlock(&phone->lock);	158	mutex_unlock(&phone->lock);
158	}	159	}
159		160
160	/** Initialize a phone structure.	161	/** Initialize a phone structure.
161	*	162	*
162	* @param phone Phone structure to be initialized.	163	* @param phone Phone structure to be initialized.
163	*/	164	*/
164	void ipc_phone_init(phone_t *phone)	165	void ipc_phone_init(phone_t *phone)
165	{	166	{
166	mutex_initialize(&phone->lock, MUTEX_PASSIVE);	167	mutex_initialize(&phone->lock, MUTEX_PASSIVE);
167	phone->callee = NULL;	168	phone->callee = NULL;
168	phone->state = IPC_PHONE_FREE;	169	phone->state = IPC_PHONE_FREE;
169	atomic_set(&phone->active_calls, 0);	170	atomic_set(&phone->active_calls, 0);
170	}	171	}
171		172
172	/** Helper function to facilitate synchronous calls.	173	/** Helper function to facilitate synchronous calls.
173	*	174	*
174	* @param phone Destination kernel phone structure.	175	* @param phone Destination kernel phone structure.
175	* @param request Call structure with request.	176	* @param request Call structure with request.
176	*	177	*
177	* @return EOK on success or EINTR if the sleep was interrupted.	178	* @return EOK on success or EINTR if the sleep was interrupted.
178	*/	179	*/
179	int ipc_call_sync(phone_t phone, call_t request)	180	int ipc_call_sync(phone_t phone, call_t request)
180	{	181	{
181	answerbox_t sync_box;	182	answerbox_t sync_box;
182		183
183	ipc_answerbox_init(&sync_box, TASK);	184	ipc_answerbox_init(&sync_box, TASK);
184		185
185	/* We will receive data in a special box. */	186	/* We will receive data in a special box. */
186	request->callerbox = &sync_box;	187	request->callerbox = &sync_box;
187		188
188	ipc_call(phone, request);	189	ipc_call(phone, request);
189	if (!ipc_wait_for_call(&sync_box, SYNCH_NO_TIMEOUT,	190	if (!ipc_wait_for_call(&sync_box, SYNCH_NO_TIMEOUT,
190	SYNCH_FLAGS_INTERRUPTIBLE))	191	SYNCH_FLAGS_INTERRUPTIBLE))
191	return EINTR;	192	return EINTR;
192	return EOK;	193	return EOK;
193	}	194	}
194		195
195	/** Answer a message which was not dispatched and is not listed in any queue.	196	/** Answer a message which was not dispatched and is not listed in any queue.
196	*	197	*
197	* @param call Call structure to be answered.	198	* @param call Call structure to be answered.
198	*/	199	*/
199	static void _ipc_answer_free_call(call_t *call)	200	static void _ipc_answer_free_call(call_t *call)
200	{	201	{
201	answerbox_t *callerbox = call->callerbox;	202	answerbox_t *callerbox = call->callerbox;
202		203
203	call->flags \|= IPC_CALL_ANSWERED;	204	call->flags \|= IPC_CALL_ANSWERED;
204		205
205	if (call->flags & IPC_CALL_FORWARDED) {	206	if (call->flags & IPC_CALL_FORWARDED) {
206	if (call->caller_phone) {	207	if (call->caller_phone) {
207	/* Demasquerade the caller phone. */	208	/* Demasquerade the caller phone. */
208	call->data.phone = call->caller_phone;	209	call->data.phone = call->caller_phone;
209	}	210	}
210	}	211	}
211		212
212	spinlock_lock(&callerbox->lock);	213	spinlock_lock(&callerbox->lock);
213	list_append(&call->link, &callerbox->answers);	214	list_append(&call->link, &callerbox->answers);
214	spinlock_unlock(&callerbox->lock);	215	spinlock_unlock(&callerbox->lock);
215	waitq_wakeup(&callerbox->wq, WAKEUP_FIRST);	216	waitq_wakeup(&callerbox->wq, WAKEUP_FIRST);
216	}	217	}
217		218
218	/** Answer a message which is in a callee queue.	219	/** Answer a message which is in a callee queue.
219	*	220	*
220	* @param box Answerbox that is answering the message.	221	* @param box Answerbox that is answering the message.
221	* @param call Modified request that is being sent back.	222	* @param call Modified request that is being sent back.
222	*/	223	*/
223	void ipc_answer(answerbox_t box, call_t call)	224	void ipc_answer(answerbox_t box, call_t call)
224	{	225	{
225	/* Remove from active box */	226	/* Remove from active box */
226	spinlock_lock(&box->lock);	227	spinlock_lock(&box->lock);
227	list_remove(&call->link);	228	list_remove(&call->link);
228	spinlock_unlock(&box->lock);	229	spinlock_unlock(&box->lock);
229	/* Send back answer */	230	/* Send back answer */
230	_ipc_answer_free_call(call);	231	_ipc_answer_free_call(call);
231	}	232	}
232		233
233	/** Simulate sending back a message.	234	/** Simulate sending back a message.
234	*	235	*
235	* Most errors are better handled by forming a normal backward	236	* Most errors are better handled by forming a normal backward
236	* message and sending it as a normal answer.	237	* message and sending it as a normal answer.
237	*	238	*
238	* @param phone Phone structure the call should appear to come from.	239	* @param phone Phone structure the call should appear to come from.
239	* @param call Call structure to be answered.	240	* @param call Call structure to be answered.
240	* @param err Return value to be used for the answer.	241	* @param err Return value to be used for the answer.
241	*/	242	*/
242	void ipc_backsend_err(phone_t phone, call_t call, unative_t err)	243	void ipc_backsend_err(phone_t phone, call_t call, unative_t err)
243	{	244	{
244	call->data.phone = phone;	245	call->data.phone = phone;
245	atomic_inc(&phone->active_calls);	246	atomic_inc(&phone->active_calls);
246	IPC_SET_RETVAL(call->data, err);	247	IPC_SET_RETVAL(call->data, err);
247	_ipc_answer_free_call(call);	248	_ipc_answer_free_call(call);
248	}	249	}
249		250
250	/** Unsafe unchecking version of ipc_call.	251	/** Unsafe unchecking version of ipc_call.
251	*	252	*
252	* @param phone Phone structure the call comes from.	253	* @param phone Phone structure the call comes from.
253	* @param box Destination answerbox structure.	254	* @param box Destination answerbox structure.
254	* @param call Call structure with request.	255	* @param call Call structure with request.
255	*/	256	*/
256	static void _ipc_call(phone_t phone, answerbox_t box, call_t *call)	257	static void _ipc_call(phone_t phone, answerbox_t box, call_t *call)
257	{	258	{
258	if (!(call->flags & IPC_CALL_FORWARDED)) {	259	if (!(call->flags & IPC_CALL_FORWARDED)) {
259	atomic_inc(&phone->active_calls);	260	atomic_inc(&phone->active_calls);
260	call->data.phone = phone;	261	call->data.phone = phone;
261	}	262	}
262		263
263	spinlock_lock(&box->lock);	264	spinlock_lock(&box->lock);
264	list_append(&call->link, &box->calls);	265	list_append(&call->link, &box->calls);
265	spinlock_unlock(&box->lock);	266	spinlock_unlock(&box->lock);
266	waitq_wakeup(&box->wq, WAKEUP_FIRST);	267	waitq_wakeup(&box->wq, WAKEUP_FIRST);
267	}	268	}
268		269
269	/** Send an asynchronous request using a phone to an answerbox.	270	/** Send an asynchronous request using a phone to an answerbox.
270	*	271	*
271	* @param phone Phone structure the call comes from and which is	272	* @param phone Phone structure the call comes from and which is
272	* connected to the destination answerbox.	273	* connected to the destination answerbox.
273	* @param call Call structure with request.	274	* @param call Call structure with request.
274	*	275	*
275	* @return Return 0 on success, ENOENT on error.	276	* @return Return 0 on success, ENOENT on error.
276	*/	277	*/
277	int ipc_call(phone_t phone, call_t call)	278	int ipc_call(phone_t phone, call_t call)
278	{	279	{
279	answerbox_t *box;	280	answerbox_t *box;
280		281
281	mutex_lock(&phone->lock);	282	mutex_lock(&phone->lock);
282	if (phone->state != IPC_PHONE_CONNECTED) {	283	if (phone->state != IPC_PHONE_CONNECTED) {
283	mutex_unlock(&phone->lock);	284	mutex_unlock(&phone->lock);
284	if (call->flags & IPC_CALL_FORWARDED) {	285	if (call->flags & IPC_CALL_FORWARDED) {
285	IPC_SET_RETVAL(call->data, EFORWARD);	286	IPC_SET_RETVAL(call->data, EFORWARD);
286	_ipc_answer_free_call(call);	287	_ipc_answer_free_call(call);
287	} else {	288	} else {
288	if (phone->state == IPC_PHONE_HUNGUP)	289	if (phone->state == IPC_PHONE_HUNGUP)
289	ipc_backsend_err(phone, call, EHANGUP);	290	ipc_backsend_err(phone, call, EHANGUP);
290	else	291	else
291	ipc_backsend_err(phone, call, ENOENT);	292	ipc_backsend_err(phone, call, ENOENT);
292	}	293	}
293	return ENOENT;	294	return ENOENT;
294	}	295	}
295	box = phone->callee;	296	box = phone->callee;
296	_ipc_call(phone, box, call);	297	_ipc_call(phone, box, call);
297		298
298	mutex_unlock(&phone->lock);	299	mutex_unlock(&phone->lock);
299	return 0;	300	return 0;
300	}	301	}
301		302
302	/** Disconnect phone from answerbox.	303	/** Disconnect phone from answerbox.
303	*	304	*
304	* This call leaves the phone in the HUNGUP state. The change to 'free' is done	305	* This call leaves the phone in the HUNGUP state. The change to 'free' is done
305	* lazily later.	306	* lazily later.
306	*	307	*
307	* @param phone Phone structure to be hung up.	308	* @param phone Phone structure to be hung up.
308	*	309	*
309	* @return Return 0 if the phone is disconnected.	310	* @return Return 0 if the phone is disconnected.
310	* Return -1 if the phone was already disconnected.	311	* Return -1 if the phone was already disconnected.
311	*/	312	*/
312	int ipc_phone_hangup(phone_t *phone)	313	int ipc_phone_hangup(phone_t *phone)
313	{	314	{
314	answerbox_t *box;	315	answerbox_t *box;
315	call_t *call;	316	call_t *call;
316		317
317	mutex_lock(&phone->lock);	318	mutex_lock(&phone->lock);
318	if (phone->state == IPC_PHONE_FREE \|\|	319	if (phone->state == IPC_PHONE_FREE \|\|
319	phone->state == IPC_PHONE_HUNGUP \|\|	320	phone->state == IPC_PHONE_HUNGUP \|\|
320	phone->state == IPC_PHONE_CONNECTING) {	321	phone->state == IPC_PHONE_CONNECTING) {
321	mutex_unlock(&phone->lock);	322	mutex_unlock(&phone->lock);
322	return -1;	323	return -1;
323	}	324	}
324	box = phone->callee;	325	box = phone->callee;
325	if (phone->state != IPC_PHONE_SLAMMED) {	326	if (phone->state != IPC_PHONE_SLAMMED) {
326	/* Remove myself from answerbox */	327	/* Remove myself from answerbox */
327	spinlock_lock(&box->lock);	328	spinlock_lock(&box->lock);
328	list_remove(&phone->link);	329	list_remove(&phone->link);
329	spinlock_unlock(&box->lock);	330	spinlock_unlock(&box->lock);
330		331
331	if (phone->state != IPC_PHONE_SLAMMED) {	332	if (phone->state != IPC_PHONE_SLAMMED) {
332	call = ipc_call_alloc(0);	333	call = ipc_call_alloc(0);
333	IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);	334	IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);
334	call->flags \|= IPC_CALL_DISCARD_ANSWER;	335	call->flags \|= IPC_CALL_DISCARD_ANSWER;
335	_ipc_call(phone, box, call);	336	_ipc_call(phone, box, call);
336	}	337	}
337	}	338	}
338		339
339	phone->state = IPC_PHONE_HUNGUP;	340	phone->state = IPC_PHONE_HUNGUP;
340	mutex_unlock(&phone->lock);	341	mutex_unlock(&phone->lock);
341		342
342	return 0;	343	return 0;
343	}	344	}
344		345
345	/** Forwards call from one answerbox to another one.	346	/** Forwards call from one answerbox to another one.
346	*	347	*
347	* @param call Call structure to be redirected.	348	* @param call Call structure to be redirected.
348	* @param newphone Phone structure to target answerbox.	349	* @param newphone Phone structure to target answerbox.
349	* @param oldbox Old answerbox structure.	350	* @param oldbox Old answerbox structure.
350	* @param mode Flags that specify mode of the forward operation.	351	* @param mode Flags that specify mode of the forward operation.
351	*	352	*
352	* @return Return 0 if forwarding succeeded or an error code if	353	* @return Return 0 if forwarding succeeded or an error code if
353	* there was error.	354	* there was error.
354	*	355	*
355	* The return value serves only as an information for the forwarder,	356	* The return value serves only as an information for the forwarder,
356	* the original caller is notified automatically with EFORWARD.	357	* the original caller is notified automatically with EFORWARD.
357	*/	358	*/
358	int ipc_forward(call_t call, phone_t newphone, answerbox_t *oldbox, int mode)	359	int ipc_forward(call_t call, phone_t newphone, answerbox_t *oldbox, int mode)
359	{	360	{
360	spinlock_lock(&oldbox->lock);	361	spinlock_lock(&oldbox->lock);
361	list_remove(&call->link);	362	list_remove(&call->link);
362	spinlock_unlock(&oldbox->lock);	363	spinlock_unlock(&oldbox->lock);
363		364
364	if (mode & IPC_FF_ROUTE_FROM_ME) {	365	if (mode & IPC_FF_ROUTE_FROM_ME) {
365	if (!call->caller_phone)	366	if (!call->caller_phone)
366	call->caller_phone = call->data.phone;	367	call->caller_phone = call->data.phone;
367	call->data.phone = newphone;	368	call->data.phone = newphone;
368	}	369	}
369		370
370	return ipc_call(newphone, call);	371	return ipc_call(newphone, call);
371	}	372	}
372		373
373		374
374	/** Wait for a phone call.	375	/** Wait for a phone call.
375	*	376	*
376	* @param box Answerbox expecting the call.	377	* @param box Answerbox expecting the call.
377	* @param usec Timeout in microseconds. See documentation for	378	* @param usec Timeout in microseconds. See documentation for
378	* waitq_sleep_timeout() for decription of its special	379	* waitq_sleep_timeout() for decription of its special
379	* meaning.	380	* meaning.
380	* @param flags Select mode of sleep operation. See documentation for	381	* @param flags Select mode of sleep operation. See documentation for
381	* waitq_sleep_timeout() for description of its special	382	* waitq_sleep_timeout() for description of its special
382	* meaning.	383	* meaning.
383	* @return Recived call structure or NULL.	384	* @return Recived call structure or NULL.
384	*	385	*
385	* To distinguish between a call and an answer, have a look at call->flags.	386	* To distinguish between a call and an answer, have a look at call->flags.
386	*/	387	*/
387	call_t ipc_wait_for_call(answerbox_t box, uint32_t usec, int flags)	388	call_t ipc_wait_for_call(answerbox_t box, uint32_t usec, int flags)
388	{	389	{
389	call_t *request;	390	call_t *request;
390	ipl_t ipl;	391	ipl_t ipl;
391	int rc;	392	int rc;
392		393
393	restart:	394	restart:
394	rc = waitq_sleep_timeout(&box->wq, usec, flags);	395	rc = waitq_sleep_timeout(&box->wq, usec, flags);
395	if (SYNCH_FAILED(rc))	396	if (SYNCH_FAILED(rc))
396	return NULL;	397	return NULL;
397		398
398	spinlock_lock(&box->lock);	399	spinlock_lock(&box->lock);
399	if (!list_empty(&box->irq_notifs)) {	400	if (!list_empty(&box->irq_notifs)) {
400	ipl = interrupts_disable();	401	ipl = interrupts_disable();
401	spinlock_lock(&box->irq_lock);	402	spinlock_lock(&box->irq_lock);
402		403
403	request = list_get_instance(box->irq_notifs.next, call_t, link);	404	request = list_get_instance(box->irq_notifs.next, call_t, link);
404	list_remove(&request->link);	405	list_remove(&request->link);
405		406
406	spinlock_unlock(&box->irq_lock);	407	spinlock_unlock(&box->irq_lock);
407	interrupts_restore(ipl);	408	interrupts_restore(ipl);
408	} else if (!list_empty(&box->answers)) {	409	} else if (!list_empty(&box->answers)) {
409	/* Handle asynchronous answers */	410	/* Handle asynchronous answers */
410	request = list_get_instance(box->answers.next, call_t, link);	411	request = list_get_instance(box->answers.next, call_t, link);
411	list_remove(&request->link);	412	list_remove(&request->link);
412	atomic_dec(&request->data.phone->active_calls);	413	atomic_dec(&request->data.phone->active_calls);
413	} else if (!list_empty(&box->calls)) {	414	} else if (!list_empty(&box->calls)) {
414	/* Handle requests */	415	/* Handle requests */
415	request = list_get_instance(box->calls.next, call_t, link);	416	request = list_get_instance(box->calls.next, call_t, link);
416	list_remove(&request->link);	417	list_remove(&request->link);
417	/* Append request to dispatch queue */	418	/* Append request to dispatch queue */
418	list_append(&request->link, &box->dispatched_calls);	419	list_append(&request->link, &box->dispatched_calls);
419	} else {	420	} else {
420	/* This can happen regularly after ipc_cleanup */	421	/* This can happen regularly after ipc_cleanup */
421	spinlock_unlock(&box->lock);	422	spinlock_unlock(&box->lock);
422	goto restart;	423	goto restart;
423	}	424	}
424	spinlock_unlock(&box->lock);	425	spinlock_unlock(&box->lock);
425	return request;	426	return request;
426	}	427	}
427		428
428	/** Answer all calls from list with EHANGUP answer.	429	/** Answer all calls from list with EHANGUP answer.
429	*	430	*
430	* @param lst Head of the list to be cleaned up.	431	* @param lst Head of the list to be cleaned up.
431	*/	432	*/
432	void ipc_cleanup_call_list(link_t *lst)	433	void ipc_cleanup_call_list(link_t *lst)
433	{	434	{
434	call_t *call;	435	call_t *call;
435		436
436	while (!list_empty(lst)) {	437	while (!list_empty(lst)) {
437	call = list_get_instance(lst->next, call_t, link);	438	call = list_get_instance(lst->next, call_t, link);
438	if (call->buffer)	439	if (call->buffer)
439	free(call->buffer);	440	free(call->buffer);
440	list_remove(&call->link);	441	list_remove(&call->link);
441		442
442	IPC_SET_RETVAL(call->data, EHANGUP);	443	IPC_SET_RETVAL(call->data, EHANGUP);
443	_ipc_answer_free_call(call);	444	_ipc_answer_free_call(call);
444	}	445	}
445	}	446	}
446		447
447	/** Disconnects all phones connected to an answerbox.	448	/** Disconnects all phones connected to an answerbox.
448	*	449	*
449	* @param box Answerbox to disconnect phones from.	450	* @param box Answerbox to disconnect phones from.
450	* @param notify_box If true, the answerbox will get a hangup message for	451	* @param notify_box If true, the answerbox will get a hangup message for
451	* each disconnected phone.	452	* each disconnected phone.
452	*/	453	*/
453	void ipc_answerbox_slam_phones(answerbox_t *box, bool notify_box)	454	void ipc_answerbox_slam_phones(answerbox_t *box, bool notify_box)
454	{	455	{
455	phone_t *phone;	456	phone_t *phone;
456	DEADLOCK_PROBE_INIT(p_phonelck);	457	DEADLOCK_PROBE_INIT(p_phonelck);
457	ipl_t ipl;	458	ipl_t ipl;
458	call_t *call;	459	call_t *call;
459		460
460	call = notify_box ? ipc_call_alloc(0) : NULL;	461	call = notify_box ? ipc_call_alloc(0) : NULL;
461		462
462	/* Disconnect all phones connected to our answerbox */	463	/* Disconnect all phones connected to our answerbox */
463	restart_phones:	464	restart_phones:
464	ipl = interrupts_disable();	465	ipl = interrupts_disable();
465	spinlock_lock(&box->lock);	466	spinlock_lock(&box->lock);
466	while (!list_empty(&box->connected_phones)) {	467	while (!list_empty(&box->connected_phones)) {
467	phone = list_get_instance(box->connected_phones.next,	468	phone = list_get_instance(box->connected_phones.next,
468	phone_t, link);	469	phone_t, link);
469	if (SYNCH_FAILED(mutex_trylock(&phone->lock))) {	470	if (SYNCH_FAILED(mutex_trylock(&phone->lock))) {
470	spinlock_unlock(&box->lock);	471	spinlock_unlock(&box->lock);
471	interrupts_restore(ipl);	472	interrupts_restore(ipl);
472	DEADLOCK_PROBE(p_phonelck, DEADLOCK_THRESHOLD);	473	DEADLOCK_PROBE(p_phonelck, DEADLOCK_THRESHOLD);
473	goto restart_phones;	474	goto restart_phones;
474	}	475	}
475		476
476	/* Disconnect phone */	477	/* Disconnect phone */
477	ASSERT(phone->state == IPC_PHONE_CONNECTED);	478	ASSERT(phone->state == IPC_PHONE_CONNECTED);
478		479
479	list_remove(&phone->link);	480	list_remove(&phone->link);
480	phone->state = IPC_PHONE_SLAMMED;	481	phone->state = IPC_PHONE_SLAMMED;
481		482
482	if (notify_box) {	483	if (notify_box) {
483	mutex_unlock(&phone->lock);	484	mutex_unlock(&phone->lock);
484	spinlock_unlock(&box->lock);	485	spinlock_unlock(&box->lock);
485	interrupts_restore(ipl);	486	interrupts_restore(ipl);
486		487
487	/*	488	/*
488	* Send one message to the answerbox for each	489	* Send one message to the answerbox for each
489	* phone. Used to make sure the kbox thread	490	* phone. Used to make sure the kbox thread
490	* wakes up after the last phone has been	491	* wakes up after the last phone has been
491	* disconnected.	492	* disconnected.
492	*/	493	*/
493	IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);	494	IPC_SET_METHOD(call->data, IPC_M_PHONE_HUNGUP);
494	call->flags \|= IPC_CALL_DISCARD_ANSWER;	495	call->flags \|= IPC_CALL_DISCARD_ANSWER;
495	_ipc_call(phone, box, call);	496	_ipc_call(phone, box, call);
496		497
497	/* Allocate another call in advance */	498	/* Allocate another call in advance */
498	call = ipc_call_alloc(0);	499	call = ipc_call_alloc(0);
499		500

Subversion Repositories HelenOS

(root)/branches/sparc/kernel/generic/src/ipc/ipc.c – Rev 3492 → 3862