/*
* Copyright (c) 2009 Jakub Jermar
* 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 kernel_generic
* @{
*/
/**
* @file
* @brief Kernel event notifications.
*/
#include <assert.h>
#include <ipc/event.h>
#include <mm/slab.h>
#include <typedefs.h>
#include <synch/spinlock.h>
#include <console/console.h>
#include <proc/task.h>
#include <errno.h>
#include <arch.h>
/** The events array. */
static event_t events[EVENT_END];
static void event_initialize(event_t *event)
{
spinlock_initialize(&event->lock, "event.lock");
event->answerbox = NULL;
event->counter = 0;
event->imethod = 0;
event->masked = false;
event->unmask_callback = NULL;
}
static event_t *evno2event(int evno, task_t *task)
{
assert(evno < EVENT_TASK_END);
event_t *event;
if (evno < EVENT_END)
event = &events[(event_type_t) evno];
else
event = &task->events[(event_task_type_t) evno - EVENT_END];
return event;
}
/** Initialize kernel events.
*
*/
void event_init(void)
{
for (unsigned int i = 0; i < EVENT_END; i++)
event_initialize(evno2event(i, NULL));
}
void event_task_init(task_t *task)
{
for (unsigned int i = EVENT_END; i < EVENT_TASK_END; i++)
event_initialize(evno2event(i, task));
}
/** Unsubscribe kernel events associated with an answerbox
*
* @param answerbox Answerbox to be unsubscribed.
*
*/
void event_cleanup_answerbox(answerbox_t *answerbox)
{
for (unsigned int i = 0; i < EVENT_END; i++) {
spinlock_lock(&events[i].lock);
if (events[i].answerbox == answerbox) {
events[i].answerbox = NULL;
events[i].counter = 0;
events[i].imethod = 0;
events[i].masked = false;
}
spinlock_unlock(&events[i].lock);
}
}
static void _event_set_unmask_callback(event_t *event, event_callback_t callback)
{
spinlock_lock(&event->lock);
event->unmask_callback = callback;
spinlock_unlock(&event->lock);
}
/** Define a callback function for the event unmask event.
*
* @param evno Event type.
* @param callback Callback function to be called when
* the event is unmasked.
*
*/
void event_set_unmask_callback(event_type_t evno, event_callback_t callback)
{
assert(evno < EVENT_END);
_event_set_unmask_callback(evno2event(evno, NULL), callback);
}
void event_task_set_unmask_callback(task_t *task, event_task_type_t evno,
event_callback_t callback)
{
assert(evno >= (int) EVENT_END);
assert(evno < EVENT_TASK_END);
_event_set_unmask_callback(evno2event(evno, task), callback);
}
static errno_t event_enqueue(event_t *event, bool mask, sysarg_t a1, sysarg_t a2,
sysarg_t a3, sysarg_t a4, sysarg_t a5)
{
errno_t res;
spinlock_lock(&event->lock);
if (event->answerbox != NULL) {
if (!event->masked) {
call_t *call = ipc_call_alloc();
if (call) {
call->flags |= IPC_CALL_NOTIF;
call->priv = ++event->counter;
ipc_set_imethod(&call->data, event->imethod);
ipc_set_arg1(&call->data, a1);
ipc_set_arg2(&call->data, a2);
ipc_set_arg3(&call->data, a3);
ipc_set_arg4(&call->data, a4);
ipc_set_arg5(&call->data, a5);
call->data.task_id = TASK ? TASK->taskid : 0;
irq_spinlock_lock(&event->answerbox->irq_lock,
true);
list_append(&call->ab_link,
&event->answerbox->irq_notifs);
irq_spinlock_unlock(&event->answerbox->irq_lock,
true);
waitq_wake_one(&event->answerbox->wq);
if (mask)
event->masked = true;
res = EOK;
} else
res = ENOMEM;
} else
res = EBUSY;
} else
res = ENOENT;
spinlock_unlock(&event->lock);
return res;
}
/** Send kernel notification event
*
* @param evno Event type.
* @param mask Mask further notifications after a successful
* sending.
* @param a1 First argument.
* @param a2 Second argument.
* @param a3 Third argument.
* @param a4 Fourth argument.
* @param a5 Fifth argument.
*
* @return EOK if notification was successfully sent.
* @return ENOMEM if the notification IPC message failed to allocate.
* @return EBUSY if the notifications of the given type are
* currently masked.
* @return ENOENT if the notifications of the given type are
* currently not subscribed.
*
*/
errno_t event_notify(event_type_t evno, bool mask, sysarg_t a1, sysarg_t a2,
sysarg_t a3, sysarg_t a4, sysarg_t a5)
{
assert(evno < EVENT_END);
return event_enqueue(evno2event(evno, NULL), mask, a1, a2, a3, a4, a5);
}
/** Send per-task kernel notification event
*
* @param task Destination task.
* @param evno Event type.
* @param mask Mask further notifications after a successful
* sending.
* @param a1 First argument.
* @param a2 Second argument.
* @param a3 Third argument.
* @param a4 Fourth argument.
* @param a5 Fifth argument.
*
* @return EOK if notification was successfully sent.
* @return ENOMEM if the notification IPC message failed to allocate.
* @return EBUSY if the notifications of the given type are
* currently masked.
* @return ENOENT if the notifications of the given type are
* currently not subscribed.
*
*/
errno_t event_task_notify(task_t *task, event_task_type_t evno, bool mask,
sysarg_t a1, sysarg_t a2, sysarg_t a3, sysarg_t a4, sysarg_t a5)
{
assert(evno >= (int) EVENT_END);
assert(evno < EVENT_TASK_END);
return event_enqueue(evno2event(evno, task), mask, a1, a2, a3, a4, a5);
}
/** Subscribe event notifications
*
* @param evno Event type.
* @param imethod IPC interface and method to be used for
* the notifications.
* @param answerbox Answerbox to send the notifications to.
*
* @return EOK if the subscription was successful.
* @return EEXIST if the notifications of the given type are
* already subscribed.
*
*/
static errno_t event_subscribe(event_t *event, sysarg_t imethod,
answerbox_t *answerbox)
{
errno_t res;
spinlock_lock(&event->lock);
if (event->answerbox == NULL) {
event->answerbox = answerbox;
event->imethod = imethod;
event->counter = 0;
event->masked = false;
res = EOK;
} else
res = EEXIST;
spinlock_unlock(&event->lock);
return res;
}
/** Unsubscribe event notifications
*
* @param evno Event type.
* @param answerbox Answerbox used to send the notifications to.
*
* @return EOK if the subscription was successful.
* @return EEXIST if the notifications of the given type are
* already subscribed.
*
*/
static errno_t event_unsubscribe(event_t *event, answerbox_t *answerbox)
{
errno_t res;
spinlock_lock(&event->lock);
if (event->answerbox == answerbox) {
event->answerbox = NULL;
event->counter = 0;
event->imethod = 0;
event->masked = false;
res = EOK;
} else
res = ENOENT;
spinlock_unlock(&event->lock);
return res;
}
/** Unmask event notifications
*
* @param evno Event type to unmask.
*
*/
static void event_unmask(event_t *event)
{
spinlock_lock(&event->lock);
event->masked = false;
event_callback_t callback = event->unmask_callback;
spinlock_unlock(&event->lock);
/*
* Check if there is an unmask callback
* function defined for this event.
*/
if (callback != NULL)
callback(event);
}
/** Event notification subscription syscall wrapper
*
* @param evno Event type to subscribe.
* @param imethod IPC interface and method to be used for
* the notifications.
*
* @return EOK on success.
* @return ELIMIT on unknown event type.
* @return EEXIST if the notifications of the given type are
* already subscribed.
*
*/
sys_errno_t sys_ipc_event_subscribe(sysarg_t evno, sysarg_t imethod)
{
if (evno >= EVENT_TASK_END)
return ELIMIT;
return (sys_errno_t) event_subscribe(evno2event(evno, TASK),
(sysarg_t) imethod, &TASK->answerbox);
}
/** Event notification unsubscription syscall wrapper
*
* @param evno Event type to unsubscribe.
*
* @return EOK on success.
* @return ELIMIT on unknown event type.
* @return ENOENT if the notification of the given type is not
* subscribed.
*/
sys_errno_t sys_ipc_event_unsubscribe(sysarg_t evno)
{
if (evno >= EVENT_TASK_END)
return ELIMIT;
return (sys_errno_t) event_unsubscribe(evno2event(evno, TASK),
&TASK->answerbox);
}
/** Event notification unmask syscall wrapper
*
* Note that currently no tests are performed whether the calling
* task is entitled to unmask the notifications. However, thanks
* to the fact that notification masking is only a performance
* optimization, this has probably no security implications.
*
* @param evno Event type to unmask.
*
* @return EOK on success.
* @return ELIMIT on unknown event type.
*
*/
sys_errno_t sys_ipc_event_unmask(sysarg_t evno)
{
if (evno >= EVENT_TASK_END)
return ELIMIT;
event_unmask(evno2event(evno, TASK));
return EOK;
}
/** @}
*/