i2o_block.c

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		case 7:	printk("Optical device");break;
		default:
			printk("Type %d", type);
	}
	if(status&(1<<10))
		printk("(RAID)");
	if(((flags & (1<<3)) && !(status & (1<<3))) ||
	   ((flags & (1<<4)) && !(status & (1<<4))))
	{
		printk(KERN_INFO " Not loaded.\n");
		return 1;
	}
	printk("- %dMb, %d byte sectors",
		(int)(size>>20), blocksize);
	if(status&(1<<0))
	{
		u32 cachesize;
		i2ob_query_device(dev, 0x0003, 0, &cachesize, 4);
		cachesize>>=10;
		if(cachesize>4095)
			printk(", %dMb cache", cachesize>>10);
		else
			printk(", %dKb cache", cachesize);
	}
	printk(".\n");
	printk(KERN_INFO "%s: Maximum sectors/read set to %d.\n", 
		d->dev_name, i2ob_max_sectors[unit]);

	/* 
	 * If this is the first I2O block device found on this IOP,
	 * we need to initialize all the queue data structures
	 * before any I/O can be performed. If it fails, this
	 * device is useless.
	 */
	if(!i2ob_queues[c->unit]) {
		if(i2ob_init_iop(c->unit))
			return 1;
	}

	/* 
	 * This will save one level of lookup/indirection in critical 
	 * code so that we can directly get the queue ptr from the
	 * device instead of having to go the IOP data structure.
	 */
	dev->req_queue = &i2ob_queues[c->unit]->req_queue;

	grok_partitions(&i2ob_gendisk, unit>>4, 1<<4, (long)(size>>9));

	/*
	 * Register for the events we're interested in and that the
	 * device actually supports.
	 */
	i2o_event_register(c, d->lct_data.tid, i2ob_context, unit, 
		(I2OB_EVENT_MASK & d->lct_data.event_capabilities));

	return 0;
}

/*
 * Initialize IOP specific queue structures.  This is called
 * once for each IOP that has a block device sitting behind it.
 */
static int i2ob_init_iop(unsigned int unit)
{
	int i;

	i2ob_queues[unit] = (struct i2ob_iop_queue*)
		kmalloc(sizeof(struct i2ob_iop_queue), GFP_ATOMIC);
	if(!i2ob_queues[unit])
	{
		printk(KERN_WARNING
			"Could not allocate request queue for I2O block device!\n");
		return -1;
	}

	for(i = 0; i< MAX_I2OB_DEPTH; i++)
	{
		i2ob_queues[unit]->request_queue[i].next = 
			&i2ob_queues[unit]->request_queue[i+1];
		i2ob_queues[unit]->request_queue[i].num = i;
	}
	
	/* Queue is MAX_I2OB + 1... */
	i2ob_queues[unit]->request_queue[i].next = NULL;
	i2ob_queues[unit]->i2ob_qhead = &i2ob_queues[unit]->request_queue[0];
	atomic_set(&i2ob_queues[unit]->queue_depth, 0);

	blk_init_queue(&i2ob_queues[unit]->req_queue, i2ob_request);
	blk_queue_headactive(&i2ob_queues[unit]->req_queue, 0);
	i2ob_queues[unit]->req_queue.back_merge_fn = i2ob_back_merge;
	i2ob_queues[unit]->req_queue.front_merge_fn = i2ob_front_merge;
	i2ob_queues[unit]->req_queue.merge_requests_fn = i2ob_merge_requests;
	i2ob_queues[unit]->req_queue.queuedata = &i2ob_queues[unit];

	return 0;
}

/*
 * Get the request queue for the given device.
 */	
static request_queue_t* i2ob_get_queue(kdev_t dev)
{
	int unit = MINOR(dev)&0xF0;

	return i2ob_dev[unit].req_queue;
}

/*
 * Probe the I2O subsytem for block class devices
 */
static void i2ob_probe(void)
{
	int i;
	int unit = 0;
	int warned = 0;
		
	for(i=0; i< MAX_I2O_CONTROLLERS; i++)
	{
		struct i2o_controller *c=i2o_find_controller(i);
		struct i2o_device *d;
	
		if(c==NULL)
			continue;

		for(d=c->devices;d!=NULL;d=d->next)
		{
			if(d->lct_data.class_id!=I2O_CLASS_RANDOM_BLOCK_STORAGE)
				continue;

			if(d->lct_data.user_tid != 0xFFF)
				continue;

			if(i2o_claim_device(d, &i2o_block_handler))
			{
				printk(KERN_WARNING "i2o_block: Controller %d, TID %d\n", c->unit,
					d->lct_data.tid);
				printk(KERN_WARNING "\tDevice refused claim! Skipping installation\n");
				continue;
			}

			if(unit<MAX_I2OB<<4)
			{
 				/*
				 * Get the device and fill in the
				 * Tid and controller.
				 */
				struct i2ob_device *dev=&i2ob_dev[unit];
				dev->i2odev = d; 
				dev->controller = c;
				dev->unit = c->unit;
				dev->tid = d->lct_data.tid;

				if(i2ob_install_device(c,d,unit))
					printk(KERN_WARNING "Could not install I2O block device\n");
				else
				{
					unit+=16;
					i2ob_dev_count++;

					/* We want to know when device goes away */
					i2o_device_notify_on(d, &i2o_block_handler);
				}
			}
			else
			{
				if(!warned++)
					printk(KERN_WARNING "i2o_block: too many device, registering only %d.\n", unit>>4);
			}
			i2o_release_device(d, &i2o_block_handler);
		}
		i2o_unlock_controller(c);
	}
}

/*
 * New device notification handler.  Called whenever a new
 * I2O block storage device is added to the system.
 * 
 * Should we spin lock around this to keep multiple devs from 
 * getting updated at the same time? 
 * 
 */
void i2ob_new_device(struct i2o_controller *c, struct i2o_device *d)
{
	struct i2ob_device *dev;
	int unit = 0;

	printk(KERN_INFO "i2o_block: New device detected\n");
	printk(KERN_INFO "   Controller %d Tid %d\n",c->unit, d->lct_data.tid);

	/* Check for available space */
	if(i2ob_dev_count>=MAX_I2OB<<4)
	{
		printk(KERN_ERR "i2o_block: No more devices allowed!\n");
		return;
	}
	for(unit = 0; unit < (MAX_I2OB<<4); unit += 16)
	{
		if(!i2ob_dev[unit].i2odev)
			break;
	}

	/*
	 * Creating a RAID 5 volume takes a little while and the UTIL_CLAIM
	 * will fail if we don't give the card enough time to do it's magic, 
	 * so we just sleep for a little while and let it do it's thing
	 */
	current->state = TASK_INTERRUPTIBLE;
	schedule_timeout(3*HZ);

	if(i2o_claim_device(d, &i2o_block_handler))
	{
		printk(KERN_INFO 
			"i2o_block: Unable to claim device. Installation aborted\n");
		return;
	}

	dev = &i2ob_dev[unit];
	dev->i2odev = d; 
	dev->controller = c;
	dev->tid = d->lct_data.tid;

	if(i2ob_install_device(c,d,unit))
		printk(KERN_ERR "i2o_block: Could not install new device\n");
	else	
	{
		i2ob_dev_count++;
		i2o_device_notify_on(d, &i2o_block_handler);
	}

	i2o_release_device(d, &i2o_block_handler);
 
	return;
}

/*
 * Deleted device notification handler.  Called when a device we
 * are talking to has been deleted by the user or some other
 * mysterious fource outside the kernel.
 */
void i2ob_del_device(struct i2o_controller *c, struct i2o_device *d)
{	
	int unit = 0;
	int i = 0;
	int flags;

	spin_lock_irqsave(&io_request_lock, flags);

	/*
	 * Need to do this...we somtimes get two events from the IRTOS
	 * in a row and that causes lots of problems.
	 */
	i2o_device_notify_off(d, &i2o_block_handler);

	printk(KERN_INFO "I2O Block Device Deleted\n");

	for(unit = 0; unit < MAX_I2OB<<4; unit += 16)
	{
		if(i2ob_dev[unit].i2odev == d)
		{
			printk(KERN_INFO "  /dev/%s: Controller %d Tid %d\n", 
				d->dev_name, c->unit, d->lct_data.tid);
			break;
		}
	}
	if(unit >= MAX_I2OB<<4)
	{
		printk(KERN_ERR "i2ob_del_device called, but not in dev table!\n");
		return;
	}

	/* 
	 * This will force errors when i2ob_get_queue() is called
	 * by the kenrel.
	 */
	i2ob_dev[unit].req_queue = NULL;
	for(i = unit; i <= unit+15; i++)
	{
		i2ob_dev[i].i2odev = NULL;
		i2ob_sizes[i] = 0;
		i2ob_hardsizes[i] = 0;
		i2ob_max_sectors[i] = 0;
		i2ob[i].nr_sects = 0;
		i2ob_gendisk.part[i].nr_sects = 0;
	}
	spin_unlock_irqrestore(&io_request_lock, flags);

	/*
	 * Sync the device...this will force all outstanding I/Os
	 * to attempt to complete, thus causing error messages.
	 * We have to do this as the user could immediatelly create
	 * a new volume that gets assigned the same minor number.
	 * If there are still outstanding writes to the device,
	 * that could cause data corruption on the new volume!
	 *
	 * The truth is that deleting a volume that you are currently
	 * accessing will do _bad things_ to your system.  This 
	 * handler will keep it from crashing, but must probably 
	 * you'll have to do a 'reboot' to get the system running
	 * properly.  Deleting disks you are using is dumb.  
	 * Umount them first and all will be good!
	 *
	 * It's not this driver's job to protect the system from
	 * dumb user mistakes :)
	 */
	if(i2ob_dev[unit].refcnt)
		fsync_dev(MKDEV(MAJOR_NR,unit));

	/*
	 * Decrease usage count for module
	 */	
	while(i2ob_dev[unit].refcnt--)
		MOD_DEC_USE_COUNT;

	i2ob_dev[unit].refcnt = 0;
	
	i2ob_dev[i].tid = 0;

	/* 
	 * Do we need this?
	 * The media didn't really change...the device is just gone
	 */
	i2ob_media_change_flag[unit] = 1;

	i2ob_dev_count--;	

	return;
}

/*
 *	Have we seen a media change ?
 */
static int i2ob_media_change(kdev_t dev)
{
	int i=MINOR(dev);
	i>>=4;
	if(i2ob_media_change_flag[i])
	{
		i2ob_media_change_flag[i]=0;
		return 1;
	}
	return 0;
}

static int i2ob_revalidate(kdev_t dev)
{
	return do_i2ob_revalidate(dev, 0);
}

/*
 * Reboot notifier.  This is called by i2o_core when the system
 * shuts down.
 */
static void i2ob_reboot_event(void)
{
	int i;
	
	for(i=0;i<MAX_I2OB;i++)
	{
		struct i2ob_device *dev=&i2ob_dev[(i<<4)];
		
		if(dev->refcnt!=0)
		{
			/*
			 *	Flush the onboard cache
			 */
			u32 msg[5];
			int *query_done = &dev->done_flag;
			msg[0] = FIVE_WORD_MSG_SIZE|SGL_OFFSET_0;
			msg[1] = I2O_CMD_BLOCK_CFLUSH<<24|HOST_TID<<12|dev->tid;
			msg[2] = i2ob_context|0x40000000;
			msg[3] = (u32)query_done;
			msg[4] = 60<<16;
			i2o_post_wait(dev->controller, msg, 20, 2);

			/*
			 *	Unlock the media
			 */
			msg[0] = FIVE_WORD_MSG_SIZE|SGL_OFFSET_0;
			msg[1] = I2O_CMD_BLOCK_MUNLOCK<<24|HOST_TID<<12|dev->tid;
			msg[2] = i2ob_context|0x40000000;
			msg[3] = (u32)query_done;
			msg[4] = -1;
			i2o_post_wait(dev->controller, msg, 20, 2);
		}
	}	
}

static struct block_device_operations i2ob_fops =
{
   open:       i2ob_open,
   release:    i2ob_release,
   ioctl:         i2ob_ioctl,
   check_media_change:  i2ob_media_change,
   revalidate:    i2ob_revalidate,
};


static struct gendisk i2ob_gendisk = 
{
	MAJOR_NR,
	"i2o/hd",
	4,
	1<<4,
	i2ob,
	i2ob_sizes,
	0,
	NULL,
	NULL
};


/*
 * And here should be modules and kernel interface 
 *  (Just smiley confuses emacs :-)
 */

#ifdef MODULE
#define i2o_block_init init_module
#endif

int i2o_block_init(void)
{
	int i;

	printk(KERN_INFO "I2O Block Storage OSM v0.9\n");
	printk(KERN_INFO "   (c) Copyright 1999, 2000 Red Hat Software.\n");
	
	/*
	 *	Register the block device interfaces
	 */

	if (register_blkdev(MAJOR_NR, "i2o_block", &i2ob_fops)) {
		printk(KERN_ERR "Unable to get major number %d for i2o_block\n",
		       MAJOR_NR);
		return -EIO;
	}
#ifdef MODULE
	printk(KERN_INFO "i2o_block: registered device at major %d\n", MAJOR_NR);
#endif

	/*
	 *	Now fill in the boiler plate
	 */
	 
	blksize_size[MAJOR_NR] = i2ob_blksizes;
	hardsect_size[MAJOR_NR] = i2ob_hardsizes;
	blk_size[MAJOR_NR] = i2ob_sizes;
	max_sectors[MAJOR_NR] = i2ob_max_sectors;
	blk_dev[MAJOR_NR].queue = i2ob_get_queue;
	
	blk_init_queue(BLK_DEFAULT_QUEUE(MAJOR_NR), i2ob_request);
	blk_queue_headactive(BLK_DEFAULT_QUEUE(MAJOR_NR), 0);

	for (i = 0; i < MAX_I2OB << 4; i++) {
		i2ob_dev[i].refcnt = 0;
		i2ob_dev[i].flags = 0;
		i2ob_dev[i].controller = NULL;
		i2ob_dev[i].i2odev = NULL;
		i2ob_dev[i].tid = 0;
		i2ob_dev[i].head = NULL;
		i2ob_dev[i].tail = NULL;
		i2ob_blksizes[i] = 1024;
		i2ob_max_sectors[i] = 2;
	}
	
	/*
	 *	Set up the queue
	 */
	for(i = 0; i < MAX_I2O_CONTROLLERS; i++)
	{
		i2ob_queues[i] = NULL;
	}

	/*
	 *	Timers
	 */
	 
	init_timer(&i2ob_timer);
	i2ob_timer.function = i2ob_timer_handler;
	i2ob_timer.data = 0;
	
	/*
	 *	Register the OSM handler as we will need this to probe for
	 *	drives, geometry and other goodies.
	 */

	if(i2o_install_handler(&i2o_block_handler)<0)
	{
		unregister_blkdev(MAJOR_NR, "i2o_block");
		blk_cleanup_queue(BLK_DEFAULT_QUEUE(MAJOR_NR));
		printk(KERN_ERR "i2o_block: unable to register OSM.\n");
		return -EINVAL;
	}
	i2ob_context = i2o_block_handler.context;	 

	/*
	 * Initialize event handling thread
	 */
	init_MUTEX_LOCKED(&i2ob_evt_sem);
	evt_pid = kernel_thread(i2ob_evt, NULL, CLONE_SIGHAND);
	if(evt_pid < 0)
	{
		printk(KERN_ERR 
			"i2o_block: Could not initialize event thread.  Aborting\n");
		i2o_remove_handler(&i2o_block_handler);
		return 0;
	}

	/*
	 *	Finally see what is actually plugged in to our controllers
	 */
	for (i = 0; i < MAX_I2OB; i++)
		register_disk(&i2ob_gendisk, MKDEV(MAJOR_NR,i<<4), 1<<4,
			&i2ob_fops, 0);
	i2ob_probe();
	
	return 0;
}

#ifdef MODULE

EXPORT_NO_SYMBOLS;
MODULE_AUTHOR("Red Hat Software");
MODULE_DESCRIPTION("I2O Block Device OSM");

void cleanup_module(void)
{
	struct gendisk **gdp;
	int i;
	
	/*
	 * Unregister for updates from any devices..otherwise we still
	 * get them and the core jumps to random memory :O
	 */
	if(i2ob_dev_count) {
		struct i2o_device *d;
		for(i = 0; i < MAX_I2OB; i++)
		if((d=i2ob_dev[i<<4].i2odev)) {
			i2o_device_notify_off(d, &i2o_block_handler);
			i2o_event_register(d->controller, d->lct_data.tid, 
				i2ob_context, i<<4, 0);
		}
	}
	
	/*
	 *	Flush the OSM
	 */

	i2o_remove_handler(&i2o_block_handler);
		 
	/*
	 *	Return the block device
	 */
	if (unregister_blkdev(MAJOR_NR, "i2o_block") != 0)
		printk("i2o_block: cleanup_module failed\n");

	/*
	 * free request queue
	 */
	blk_cleanup_queue(BLK_DEFAULT_QUEUE(MAJOR_NR));

	if(evt_running) {
		i = kill_proc(evt_pid, SIGTERM, 1);
		if(!i) {
			int count = 5 * 100;
			while(evt_running && --count) {
				current->state = TASK_INTERRUPTIBLE;
				schedule_timeout(1);
			}
	
			if(!count)
				printk(KERN_ERR "Giving up on i2oblock thread...\n");	
		}
	}


	/*
	 *	Why isnt register/unregister gendisk in the kernel ???
	 */

	for (gdp = &gendisk_head; *gdp; gdp = &((*gdp)->next))
		if (*gdp == &i2ob_gendisk)
			break;

}
#endif