Index: kernel/generic/src/event/event.c
===================================================================
--- kernel/generic/src/event/event.c	(revision 05641a9edbf1f7a46db1517a8e99aa0ffa7bdd5d)
+++ kernel/generic/src/event/event.c	(revision 05641a9edbf1f7a46db1517a8e99aa0ffa7bdd5d)
@@ -0,0 +1,153 @@
+/*
+ * 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 generic
+ * @{
+ */
+/**
+ * @file
+ * @brief	Kernel event notifications.
+ */
+
+#include <event/event.h>
+#include <event/event_types.h>
+#include <mm/slab.h>
+#include <arch/types.h>
+#include <synch/spinlock.h>
+#include <console/console.h>
+#include <memstr.h>
+#include <errno.h>
+#include <arch.h>
+
+/**
+ * The events array.
+ * Arranging the events in this two-dimensional array should decrease the
+ * likelyhood of cacheline ping-pong.
+ */
+static event_t *events[EVENT_END];
+
+/** Initialize kernel events. */
+void event_init(void)
+{
+	int i;
+
+	for (i = 0; i < EVENT_END; i++) {
+		events[i] = (event_t *) malloc(sizeof(event_t), 0);
+		spinlock_initialize(&events[i]->lock, "event.lock");
+		events[i]->answerbox = NULL;
+		events[i]->counter = 0;
+		events[i]->method = 0;
+	}
+}
+
+static int
+event_subscribe(event_type_t e, unative_t method, answerbox_t *answerbox)
+{
+	if (e >= EVENT_END)
+		return ELIMIT;
+
+	int res = EEXISTS;
+	event_t *event = events[e];
+
+	spinlock_lock(&event->lock);
+	if (!event->answerbox) {
+		event->answerbox = answerbox;
+		event->method = method;
+		event->counter = 0;
+		res = EOK;
+	}
+	spinlock_unlock(&event->lock);
+
+	return res;
+}
+
+unative_t sys_event_subscribe(unative_t evno, unative_t method)
+{
+	return (unative_t) event_subscribe((event_type_t) evno, (unative_t)
+	    method, &TASK->answerbox);
+}
+
+bool event_is_subscribed(event_type_t e)
+{
+	bool res;
+
+	ASSERT(e < EVENT_END);
+	spinlock_lock(&events[e]->lock);
+	res = events[e]->answerbox != NULL;
+	spinlock_unlock(&events[e]->lock);
+
+	return res;
+}
+
+
+void event_cleanup_answerbox(answerbox_t *answerbox)
+{
+	int i;
+
+	for (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]->method = 0;
+		}
+		spinlock_unlock(&events[i]->lock);
+	}
+}
+
+void
+event_notify(event_type_t e, unative_t a1, unative_t a2, unative_t a3,
+    unative_t a4, unative_t a5)
+{
+	ASSERT(e < EVENT_END);
+	event_t *event = events[e];
+	spinlock_lock(&event->lock);
+	if (event->answerbox) {
+		call_t *call = ipc_call_alloc(FRAME_ATOMIC);
+		if (call) {
+			call->flags |= IPC_CALL_NOTIF;
+			call->priv = ++event->counter;
+			IPC_SET_METHOD(call->data, event->method);
+			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);
+
+			spinlock_lock(&event->answerbox->irq_lock);
+			list_append(&call->link, &event->answerbox->irq_notifs);
+			spinlock_unlock(&event->answerbox->irq_lock);
+
+			waitq_wakeup(&event->answerbox->wq, WAKEUP_FIRST);
+		}
+	}
+	spinlock_unlock(&event->lock);
+}
+
+/** @}
+ */
