genode/repos/base-hw/src/base/thread/start.cc

/**
 * \brief  Implementations for the start of a thread
 * \author Martin Stein
 * \author Stefan Kalkowski
 * \date   2012-02-12
 */

/*
 * Copyright (C) 2012-2013 Genode Labs GmbH
 *
 * This file is part of the Genode OS framework, which is distributed
 * under the terms of the GNU General Public License version 2.
 */

/* Genode includes */
#include <base/thread.h>
#include <base/printf.h>
#include <base/sleep.h>
#include <base/env.h>

using namespace Genode;

namespace Genode { Rm_session * env_context_area_rm_session(); }

extern Ram_dataspace_capability _main_thread_utcb_ds;
extern Native_thread_id         _main_thread_id;


/**
 * Return virtual UTCB location of main threads
 */
Native_utcb * main_thread_utcb() { return UTCB_MAIN_THREAD; }


/*****************
 ** Thread_base **
 *****************/

void Thread_base::_init_platform_thread(size_t quota, Type type)
{
	if (!_cpu_session) { _cpu_session = env()->cpu_session(); }
	if (type == NORMAL) {

		/* create server object */
		char buf[48];
		name(buf, sizeof(buf));
		_thread_cap = _cpu_session->create_thread(quota, buf, (addr_t)&_context->utcb);
		return;
	}
	/* if we got reinitialized we have to get rid of the old UTCB */
	size_t const utcb_size = sizeof(Native_utcb);
	addr_t const context_area = Native_config::context_area_virtual_base();
	addr_t const utcb_new = (addr_t)&_context->utcb - context_area;
	Rm_session * const rm = env_context_area_rm_session();
	if (type == REINITIALIZED_MAIN) { rm->detach(utcb_new); }

	/* remap initial main-thread UTCB according to context-area spec */
	try { rm->attach_at(_main_thread_utcb_ds, utcb_new, utcb_size); }
	catch(...) {
		PERR("failed to re-map UTCB");
		while (1) ;
	}
	/* adjust initial object state in case of a main thread */
	tid().thread_id = _main_thread_id;
	_thread_cap     = env()->parent()->main_thread_cap();
}


void Thread_base::_deinit_platform_thread()
{
	if (!_cpu_session)
		_cpu_session = env()->cpu_session();

	_cpu_session->kill_thread(_thread_cap);

	/* detach userland thread-context */
	size_t const size = sizeof(_context->utcb);
	addr_t utcb = Context_allocator::addr_to_base(_context) +
	              Native_config::context_virtual_size() - size -
	              Native_config::context_area_virtual_base();
	env_context_area_rm_session()->detach(utcb);

	if (_pager_cap.valid()) {
		env()->rm_session()->remove_client(_pager_cap);
	}
}


void Thread_base::start()
{
	/* assign thread to protection domain */
	env()->pd_session()->bind_thread(_thread_cap);

	/* create pager object and assign it to the thread */
	_pager_cap = env()->rm_session()->add_client(_thread_cap);
	_cpu_session->set_pager(_thread_cap, _pager_cap);

	/* attach userland thread-context */
	try {
		Ram_dataspace_capability ds = _cpu_session->utcb(_thread_cap);
		size_t const size = sizeof(_context->utcb);
		addr_t dst = Context_allocator::addr_to_base(_context) +
		             Native_config::context_virtual_size() - size -
		             Native_config::context_area_virtual_base();
		env_context_area_rm_session()->attach_at(ds, dst, size);
	} catch (...) {
		PERR("failed to attach userland thread-context");
		sleep_forever();
	}
	/* start thread with its initial IP and aligned SP */
	_cpu_session->start(_thread_cap, (addr_t)_thread_start, _context->stack_top());
}


void Thread_base::cancel_blocking()
{
	_cpu_session->cancel_blocking(_thread_cap);
}