0,0 → 1,429 |
/* |
* 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. |
*/ |
|
/* Lock ordering |
* |
* First the answerbox, then the phone |
*/ |
|
#include <synch/spinlock.h> |
#include <synch/waitq.h> |
#include <ipc/ipc.h> |
#include <errno.h> |
#include <mm/slab.h> |
#include <arch.h> |
#include <proc/task.h> |
#include <memstr.h> |
#include <debug.h> |
|
#include <print.h> |
#include <proc/thread.h> |
#include <arch/interrupt.h> |
#include <ipc/irq.h> |
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/* Open channel that is assigned automatically to new tasks */ |
answerbox_t *ipc_phone_0 = NULL; |
|
static slab_cache_t *ipc_call_slab; |
|
/* Initialize new call */ |
static void _ipc_call_init(call_t *call) |
{ |
memsetb((__address)call, sizeof(*call), 0); |
call->callerbox = &TASK->answerbox; |
call->sender = TASK; |
} |
|
/** Allocate & initialize call structure |
* |
* The call is initialized, so that the reply will be directed |
* to TASK->answerbox |
* |
* @param flags Parameters for slab_alloc (ATOMIC, etc.) |
*/ |
call_t * ipc_call_alloc(int flags) |
{ |
call_t *call; |
|
call = slab_alloc(ipc_call_slab, flags); |
_ipc_call_init(call); |
|
return call; |
} |
|
/** Initialize allocated call */ |
void ipc_call_static_init(call_t *call) |
{ |
_ipc_call_init(call); |
call->flags |= IPC_CALL_STATIC_ALLOC; |
} |
|
/** Deallocate call stracuture */ |
void ipc_call_free(call_t *call) |
{ |
slab_free(ipc_call_slab, call); |
} |
|
/** Initialize answerbox structure |
*/ |
void ipc_answerbox_init(answerbox_t *box) |
{ |
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); |
box->task = TASK; |
} |
|
/** Connect phone to answerbox */ |
void ipc_phone_connect(phone_t *phone, answerbox_t *box) |
{ |
spinlock_lock(&phone->lock); |
|
ASSERT(!phone->callee); |
phone->busy = IPC_BUSY_CONNECTED; |
phone->callee = box; |
|
spinlock_lock(&box->lock); |
list_append(&phone->list, &box->connected_phones); |
spinlock_unlock(&box->lock); |
|
spinlock_unlock(&phone->lock); |
} |
|
/** Initialize phone structure and connect phone to answerbox |
*/ |
void ipc_phone_init(phone_t *phone) |
{ |
spinlock_initialize(&phone->lock, "phone_lock"); |
phone->callee = NULL; |
phone->busy = IPC_BUSY_FREE; |
atomic_set(&phone->active_calls, 0); |
} |
|
/** Helper function to facilitate synchronous calls */ |
void ipc_call_sync(phone_t *phone, call_t *request) |
{ |
answerbox_t sync_box; |
|
ipc_answerbox_init(&sync_box); |
|
/* We will receive data on special box */ |
request->callerbox = &sync_box; |
|
ipc_call(phone, request); |
ipc_wait_for_call(&sync_box, 0); |
} |
|
/** Answer message that was not dispatched and is not entered in |
* any queue |
*/ |
static void _ipc_answer_free_call(call_t *call) |
{ |
answerbox_t *callerbox = call->callerbox; |
|
call->flags |= IPC_CALL_ANSWERED; |
|
spinlock_lock(&callerbox->lock); |
list_append(&call->list, &callerbox->answers); |
spinlock_unlock(&callerbox->lock); |
waitq_wakeup(&callerbox->wq, 0); |
} |
|
/** Answer message, that is in 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->list); |
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. |
*/ |
void ipc_backsend_err(phone_t *phone, call_t *call, __native err) |
{ |
call->data.phone = phone; |
atomic_inc(&phone->active_calls); |
if (phone->busy == IPC_BUSY_CONNECTED) |
IPC_SET_RETVAL(call->data, EHANGUP); |
else |
IPC_SET_RETVAL(call->data, ENOENT); |
|
_ipc_answer_free_call(call); |
} |
|
/* Unsafe unchecking ipc_call */ |
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->list, &box->calls); |
spinlock_unlock(&box->lock); |
waitq_wakeup(&box->wq, 0); |
} |
|
/** Send a asynchronous request using phone to answerbox |
* |
* @param phone Phone connected to answerbox |
* @param request Request to be sent |
*/ |
int ipc_call(phone_t *phone, call_t *call) |
{ |
answerbox_t *box; |
|
spinlock_lock(&phone->lock); |
|
box = phone->callee; |
if (!box) { |
/* Trying to send over disconnected phone */ |
spinlock_unlock(&phone->lock); |
if (call->flags & IPC_CALL_FORWARDED) { |
IPC_SET_RETVAL(call->data, EFORWARD); |
_ipc_answer_free_call(call); |
} else { /* Simulate sending back a message */ |
if (phone->busy == IPC_BUSY_CONNECTED) |
ipc_backsend_err(phone, call, EHANGUP); |
else |
ipc_backsend_err(phone, call, ENOENT); |
} |
|
return ENOENT; |
} |
_ipc_call(phone, box, call); |
|
spinlock_unlock(&phone->lock); |
return 0; |
} |
|
/** Disconnect phone from answerbox |
* |
* It is allowed to call disconnect on already disconnected phone |
* |
* @return 0 - phone disconnected, -1 - the phone was already disconnected |
*/ |
int ipc_phone_hangup(phone_t *phone) |
{ |
answerbox_t *box; |
call_t *call; |
|
spinlock_lock(&phone->lock); |
box = phone->callee; |
if (!box) { |
if (phone->busy == IPC_BUSY_CONNECTING) { |
spinlock_unlock(&phone->lock); |
return -1; |
} |
/* Already disconnected phone */ |
phone->busy = IPC_BUSY_FREE; |
spinlock_unlock(&phone->lock); |
return 0; |
} |
|
spinlock_lock(&box->lock); |
list_remove(&phone->list); |
phone->callee = NULL; |
spinlock_unlock(&box->lock); |
|
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->busy = IPC_BUSY_FREE; |
|
spinlock_unlock(&phone->lock); |
|
return 0; |
} |
|
/** Forwards call from one answerbox to a new one |
* |
* @param call Call to be redirected. |
* @param newphone Phone to target answerbox. |
* @param oldbox Old answerbox |
* @return 0 on forward ok, 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) |
{ |
spinlock_lock(&oldbox->lock); |
list_remove(&call->list); |
spinlock_unlock(&oldbox->lock); |
|
return ipc_call(newphone, call); |
} |
|
|
/** Wait for phone call |
* |
* @return Recived message address |
* - to distinguish between call and answer, look at call->flags |
*/ |
call_t * ipc_wait_for_call(answerbox_t *box, int flags) |
{ |
call_t *request; |
ipl_t ipl; |
|
restart: |
if (flags & IPC_WAIT_NONBLOCKING) { |
if (waitq_sleep_timeout(&box->wq,0,1) == ESYNCH_WOULD_BLOCK) |
return NULL; |
} else |
waitq_sleep(&box->wq); |
|
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, list); |
list_remove(&request->list); |
|
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, list); |
list_remove(&request->list); |
atomic_dec(&request->data.phone->active_calls); |
} else if (!list_empty(&box->calls)) { |
/* Handle requests */ |
request = list_get_instance(box->calls.next, call_t, list); |
list_remove(&request->list); |
/* Append request to dispatch queue */ |
list_append(&request->list, &box->dispatched_calls); |
} else { |
/* This can happen regularly after ipc_cleanup, remove |
* the warning in the future when the IPC is |
* more debugged */ |
printf("WARNING: Spurious IPC wakeup.\n"); |
spinlock_unlock(&box->lock); |
goto restart; |
} |
spinlock_unlock(&box->lock); |
return request; |
} |
|
/** Answer all calls from list with EHANGUP msg */ |
static void ipc_cleanup_call_list(link_t *lst) |
{ |
call_t *call; |
|
while (!list_empty(lst)) { |
call = list_get_instance(lst->next, call_t, list); |
list_remove(&call->list); |
|
IPC_SET_RETVAL(call->data, EHANGUP); |
_ipc_answer_free_call(call); |
} |
} |
|
/** Cleans up all IPC communication of the given task |
* |
* |
*/ |
void ipc_cleanup(task_t *task) |
{ |
int i; |
call_t *call; |
phone_t *phone; |
|
/* 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 answerbox */ |
restart_phones: |
spinlock_lock(&task->answerbox.lock); |
while (!list_empty(&task->answerbox.connected_phones)) { |
phone = list_get_instance(task->answerbox.connected_phones.next, |
phone_t, |
list); |
if (! spinlock_trylock(&phone->lock)) { |
spinlock_unlock(&task->answerbox.lock); |
goto restart_phones; |
} |
|
/* Disconnect phone */ |
phone->callee = NULL; |
list_remove(&phone->list); |
|
spinlock_unlock(&phone->lock); |
} |
|
/* 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 (atomic_get(&task->active_calls)) { |
call = ipc_wait_for_call(&task->answerbox, 0); |
ASSERT((call->flags & IPC_CALL_ANSWERED) || (call->flags & IPC_CALL_NOTIF)); |
ASSERT(! (call->flags & IPC_CALL_STATIC_ALLOC)); |
|
atomic_dec(&task->active_calls); |
ipc_call_free(call); |
} |
} |
|
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/** Initilize ipc subsystem */ |
void ipc_init(void) |
{ |
ipc_call_slab = slab_cache_create("ipc_call", |
sizeof(call_t), |
0, |
NULL, NULL, 0); |
ipc_irq_make_table(IRQ_COUNT); |
} |
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