xpt.c

newos is new operation system

/* 
** Copyright 2002, Thomas Kurschel. All rights reserved.
** Distributed under the terms of the NewOS License.
*/


#include "xpt_internal.h"

#include <kernel/module.h>
#include <kernel/debug.h>

#include "device_mgr.h"
#include "bus_mgr.h"
#include "periph_mgr.h"
#include "ccb_mgr.h"
#include "sg_mgr.h"

// scanning SCSI busses is time consuming - give it normal priority
#define SCAN_BUSSES_PRIORITY THREAD_MEDIUM_PRIORITY //5

#define CAM_XPT_MODULE_NAME "bus_managers/scsi/xpt/v1"


// these could be moved to appropriate header but would lead
// to inclusion of kernel/module.h in them
extern module_header xpt_driver_module, xpt_sim_module;

locked_pool_interface *locked_pool;

thread_id xpt_rescan_thread;
bool xpt_shutting_down;

// to add or remove a bus, grab this lock
recursive_lock registration_lock;

static int xpt_init()
{
	int res;
	int tmp;
	
	SHOW_FLOW0( 3, "" );
	
	if( (res = module_get( LOCKED_POOL_MODULE_NAME, 0, (void **)&locked_pool)) < 0 )
		goto err;
	
	if( (res = recursive_lock_create( &registration_lock )) < 0 )
		goto err1;
		
	xpt_highest_path_id = 0;
	xpt_periphs = NULL;
	xpt_shutting_down = false;
	
	if( (res = mutex_init( &xpt_periphs_mutex, "xpt_periphs_mutex" )) < 0 )
		goto err2;
		
	if( (res = xpt_start_rescan = sem_create( 0, "xpt_start_rescan" )) < 0 ) {
		res = xpt_start_rescan;
		goto err4;
	}
	
	if( (res = xpt_rescan_thread = thread_create_kernel_thread( "xpt_rescan_busses",
		(int (*)())xpt_rescan_threadproc, NULL )) < 0 ) 
	{
		res = xpt_rescan_thread;
		goto err5;
	}
	
	thread_set_priority( xpt_rescan_thread, SCAN_BUSSES_PRIORITY );	
	thread_resume_thread( xpt_rescan_thread );
	
	/*if( (res = xpt_init_ccb_alloc()) < 0 )
		goto err6;*/
		
	if( (res = init_temp_sg()) < 0 )
		goto err7;
		
	//load_periph_drivers();
		
	return NO_ERROR;

err7:
	/*xpt_uninit_ccb_alloc();*/
//err6:
	xpt_shutting_down = true;
	sem_release( xpt_start_rescan, 1 );	
	thread_wait_on_thread( xpt_rescan_thread, &tmp );
err5:
	sem_delete( xpt_start_rescan );
err4:
	mutex_destroy( &xpt_periphs_mutex );
err2:
	recursive_lock_destroy( &registration_lock );
err1:
	module_put( LOCKED_POOL_MODULE_NAME );
err:
	return res;	
}

static int xpt_uninit()
{
	int tmp;
	
	SHOW_INFO0( 3, "" );
	
	xpt_shutting_down = true;
	
	sem_release( xpt_start_rescan, 1 );
	thread_wait_on_thread( xpt_rescan_thread, &tmp );
	
	sem_delete( xpt_start_rescan );
	recursive_lock_destroy( &registration_lock );
	mutex_destroy( &xpt_periphs_mutex );
	
	/*xpt_uninit_ccb_alloc();*/
	uninit_temp_sg();
	
	module_put( LOCKED_POOL_MODULE_NAME );
	
	return NO_ERROR;
}

int xpt_driver_sim_init()
{
	int res;
	void *tmp;
	
	SHOW_FLOW0( 3, "" );
	
	res = module_get( CAM_XPT_MODULE_NAME, 0, &tmp );
	
	if( res < 0 ) {
		SHOW_ERROR0( 0, "Cannot lock XPT module" );
		return res;
	}
	
	return NO_ERROR;
}

int xpt_driver_sim_uninit()
{
	SHOW_FLOW0( 3, "" );
	return module_put( CAM_XPT_MODULE_NAME );
}


// add an empty entry to make module handler happy
int xpt_interface[] = { 0 };

module_header xpt_module = {
	CAM_XPT_MODULE_NAME,
	MODULE_CURR_VERSION,
	0,
	&xpt_interface,
	
	xpt_init,
	xpt_uninit
};

module_header *modules[] =
{
	&xpt_driver_module,
	&xpt_sim_module,
	&xpt_module,
	NULL
};