i2o_block.c

linux-2.6.15.6

 *	delayed_request: the delayed request with the queue to start
 *
 *	If the request queue is stopped for a disk, and there is no open
 *	request, a new event is created, which calls this function to start
 *	the queue after I2O_BLOCK_REQUEST_TIME. Otherwise the queue will never
 *	be started again.
 */
static void i2o_block_delayed_request_fn(void *delayed_request)
{
	struct i2o_block_delayed_request *dreq = delayed_request;
	struct request_queue *q = dreq->queue;
	unsigned long flags;

	spin_lock_irqsave(q->queue_lock, flags);
	blk_start_queue(q);
	spin_unlock_irqrestore(q->queue_lock, flags);
	kfree(dreq);
};

/**
 *	i2o_block_end_request - Post-processing of completed commands
 *	@req: request which should be completed
 *	@uptodate: 1 for success, 0 for I/O error, < 0 for specific error
 *	@nr_bytes: number of bytes to complete
 *
 *	Mark the request as complete. The lock must not be held when entering.
 *
 */
static void i2o_block_end_request(struct request *req, int uptodate,
				  int nr_bytes)
{
	struct i2o_block_request *ireq = req->special;
	struct i2o_block_device *dev = ireq->i2o_blk_dev;
	request_queue_t *q = req->q;
	unsigned long flags;

	if (end_that_request_chunk(req, uptodate, nr_bytes)) {
		int leftover = (req->hard_nr_sectors << KERNEL_SECTOR_SHIFT);

		if (blk_pc_request(req))
			leftover = req->data_len;

		if (end_io_error(uptodate))
			end_that_request_chunk(req, 0, leftover);
	}

	add_disk_randomness(req->rq_disk);

	spin_lock_irqsave(q->queue_lock, flags);

	end_that_request_last(req);

	if (likely(dev)) {
		dev->open_queue_depth--;
		list_del(&ireq->queue);
	}

	blk_start_queue(q);

	spin_unlock_irqrestore(q->queue_lock, flags);

	i2o_block_sglist_free(ireq);
	i2o_block_request_free(ireq);
};

/**
 *	i2o_block_reply - Block OSM reply handler.
 *	@c: I2O controller from which the message arrives
 *	@m: message id of reply
 *	qmsg: the actuall I2O message reply
 *
 *	This function gets all the message replies.
 *
 */
static int i2o_block_reply(struct i2o_controller *c, u32 m,
			   struct i2o_message *msg)
{
	struct request *req;
	int uptodate = 1;

	req = i2o_cntxt_list_get(c, le32_to_cpu(msg->u.s.tcntxt));
	if (unlikely(!req)) {
		osm_err("NULL reply received!\n");
		return -1;
	}

	/*
	 *      Lets see what is cooking. We stuffed the
	 *      request in the context.
	 */

	if ((le32_to_cpu(msg->body[0]) >> 24) != 0) {
		u32 status = le32_to_cpu(msg->body[0]);
		/*
		 *      Device not ready means two things. One is that the
		 *      the thing went offline (but not a removal media)
		 *
		 *      The second is that you have a SuperTrak 100 and the
		 *      firmware got constipated. Unlike standard i2o card
		 *      setups the supertrak returns an error rather than
		 *      blocking for the timeout in these cases.
		 *
		 *      Don't stick a supertrak100 into cache aggressive modes
		 */

		osm_err("TID %03x error status: 0x%02x, detailed status: "
			"0x%04x\n", (le32_to_cpu(msg->u.head[1]) >> 12 & 0xfff),
			status >> 24, status & 0xffff);

		req->errors++;

		uptodate = 0;
	}

	i2o_block_end_request(req, uptodate, le32_to_cpu(msg->body[1]));

	return 1;
};

static void i2o_block_event(struct i2o_event *evt)
{
	osm_debug("event received\n");
	kfree(evt);
};

/*
 *	SCSI-CAM for ioctl geometry mapping
 *	Duplicated with SCSI - this should be moved into somewhere common
 *	perhaps genhd ?
 *
 * LBA -> CHS mapping table taken from:
 *
 * "Incorporating the I2O Architecture into BIOS for Intel Architecture
 *  Platforms"
 *
 * This is an I2O document that is only available to I2O members,
 * not developers.
 *
 * From my understanding, this is how all the I2O cards do this
 *
 * Disk Size      | Sectors | Heads | Cylinders
 * ---------------+---------+-------+-------------------
 * 1 < X <= 528M  | 63      | 16    | X/(63 * 16 * 512)
 * 528M < X <= 1G | 63      | 32    | X/(63 * 32 * 512)
 * 1 < X <528M    | 63      | 16    | X/(63 * 16 * 512)
 * 1 < X <528M    | 63      | 16    | X/(63 * 16 * 512)
 *
 */
#define	BLOCK_SIZE_528M		1081344
#define	BLOCK_SIZE_1G		2097152
#define	BLOCK_SIZE_21G		4403200
#define	BLOCK_SIZE_42G		8806400
#define	BLOCK_SIZE_84G		17612800

static void i2o_block_biosparam(unsigned long capacity, unsigned short *cyls,
				unsigned char *hds, unsigned char *secs)
{
	unsigned long heads, sectors, cylinders;

	sectors = 63L;		/* Maximize sectors per track */
	if (capacity <= BLOCK_SIZE_528M)
		heads = 16;
	else if (capacity <= BLOCK_SIZE_1G)
		heads = 32;
	else if (capacity <= BLOCK_SIZE_21G)
		heads = 64;
	else if (capacity <= BLOCK_SIZE_42G)
		heads = 128;
	else
		heads = 255;

	cylinders = (unsigned long)capacity / (heads * sectors);

	*cyls = (unsigned short)cylinders;	/* Stuff return values */
	*secs = (unsigned char)sectors;
	*hds = (unsigned char)heads;
}

/**
 *	i2o_block_open - Open the block device
 *
 *	Power up the device, mount and lock the media. This function is called,
 *	if the block device is opened for access.
 *
 *	Returns 0 on success or negative error code on failure.
 */
static int i2o_block_open(struct inode *inode, struct file *file)
{
	struct i2o_block_device *dev = inode->i_bdev->bd_disk->private_data;

	if (!dev->i2o_dev)
		return -ENODEV;

	if (dev->power > 0x1f)
		i2o_block_device_power(dev, 0x02);

	i2o_block_device_mount(dev->i2o_dev, -1);

	i2o_block_device_lock(dev->i2o_dev, -1);

	osm_debug("Ready.\n");

	return 0;
};

/**
 *	i2o_block_release - Release the I2O block device
 *
 *	Unlock and unmount the media, and power down the device. Gets called if
 *	the block device is closed.
 *
 *	Returns 0 on success or negative error code on failure.
 */
static int i2o_block_release(struct inode *inode, struct file *file)
{
	struct gendisk *disk = inode->i_bdev->bd_disk;
	struct i2o_block_device *dev = disk->private_data;
	u8 operation;

	/*
	 * This is to deail with the case of an application
	 * opening a device and then the device dissapears while
	 * it's in use, and then the application tries to release
	 * it.  ex: Unmounting a deleted RAID volume at reboot.
	 * If we send messages, it will just cause FAILs since
	 * the TID no longer exists.
	 */
	if (!dev->i2o_dev)
		return 0;

	i2o_block_device_flush(dev->i2o_dev);

	i2o_block_device_unlock(dev->i2o_dev, -1);

	if (dev->flags & (1 << 3 | 1 << 4))	/* Removable */
		operation = 0x21;
	else
		operation = 0x24;

	i2o_block_device_power(dev, operation);

	return 0;
}

/**
 *	i2o_block_ioctl - Issue device specific ioctl calls.
 *	@cmd: ioctl command
 *	@arg: arg
 *
 *	Handles ioctl request for the block device.
 *
 *	Return 0 on success or negative error on failure.
 */
static int i2o_block_ioctl(struct inode *inode, struct file *file,
			   unsigned int cmd, unsigned long arg)
{
	struct gendisk *disk = inode->i_bdev->bd_disk;
	struct i2o_block_device *dev = disk->private_data;
	void __user *argp = (void __user *)arg;

	/* Anyone capable of this syscall can do *real bad* things */

	if (!capable(CAP_SYS_ADMIN))
		return -EPERM;

	switch (cmd) {
	case HDIO_GETGEO:
		{
			struct hd_geometry g;
			i2o_block_biosparam(get_capacity(disk),
					    &g.cylinders, &g.heads, &g.sectors);
			g.start = get_start_sect(inode->i_bdev);
			return copy_to_user(argp, &g, sizeof(g)) ? -EFAULT : 0;
		}

	case BLKI2OGRSTRAT:
		return put_user(dev->rcache, (int __user *)arg);
	case BLKI2OGWSTRAT:
		return put_user(dev->wcache, (int __user *)arg);
	case BLKI2OSRSTRAT:
		if (arg < 0 || arg > CACHE_SMARTFETCH)
			return -EINVAL;
		dev->rcache = arg;
		break;
	case BLKI2OSWSTRAT:
		if (arg != 0
		    && (arg < CACHE_WRITETHROUGH || arg > CACHE_SMARTBACK))
			return -EINVAL;
		dev->wcache = arg;
		break;
	}
	return -ENOTTY;
};

/**
 *	i2o_block_media_changed - Have we seen a media change?
 *	@disk: gendisk which should be verified
 *
 *	Verifies if the media has changed.
 *
 *	Returns 1 if the media was changed or 0 otherwise.
 */
static int i2o_block_media_changed(struct gendisk *disk)
{
	struct i2o_block_device *p = disk->private_data;

	if (p->media_change_flag) {
		p->media_change_flag = 0;
		return 1;
	}
	return 0;
}

/**
 *	i2o_block_transfer - Transfer a request to/from the I2O controller
 *	@req: the request which should be transfered
 *
 *	This function converts the request into a I2O message. The necessary
 *	DMA buffers are allocated and after everything is setup post the message
 *	to the I2O controller. No cleanup is done by this function. It is done
 *	on the interrupt side when the reply arrives.
 *
 *	Return 0 on success or negative error code on failure.
 */
static int i2o_block_transfer(struct request *req)
{
	struct i2o_block_device *dev = req->rq_disk->private_data;
	struct i2o_controller *c;
	int tid = dev->i2o_dev->lct_data.tid;
	struct i2o_message __iomem *msg;
	u32 __iomem *mptr;
	struct i2o_block_request *ireq = req->special;
	u32 m;
	u32 tcntxt;
	u32 sgl_offset = SGL_OFFSET_8;
	u32 ctl_flags = 0x00000000;
	int rc;
	u32 cmd;

	if (unlikely(!dev->i2o_dev)) {
		osm_err("transfer to removed drive\n");
		rc = -ENODEV;
		goto exit;
	}

	c = dev->i2o_dev->iop;

	m = i2o_msg_get(c, &msg);
	if (m == I2O_QUEUE_EMPTY) {
		rc = -EBUSY;
		goto exit;
	}

	tcntxt = i2o_cntxt_list_add(c, req);
	if (!tcntxt) {
		rc = -ENOMEM;
		goto nop_msg;
	}

	writel(i2o_block_driver.context, &msg->u.s.icntxt);
	writel(tcntxt, &msg->u.s.tcntxt);

	mptr = &msg->body[0];

	if (rq_data_dir(req) == READ) {
		cmd = I2O_CMD_BLOCK_READ << 24;

		switch (dev->rcache) {
		case CACHE_PREFETCH:
			ctl_flags = 0x201F0008;
			break;

		case CACHE_SMARTFETCH:
			if (req->nr_sectors > 16)
				ctl_flags = 0x201F0008;
			else
				ctl_flags = 0x001F0000;
			break;

		default:
			break;
		}
	} else {
		cmd = I2O_CMD_BLOCK_WRITE << 24;

		switch (dev->wcache) {
		case CACHE_WRITETHROUGH:
			ctl_flags = 0x001F0008;
			break;
		case CACHE_WRITEBACK:
			ctl_flags = 0x001F0010;
			break;
		case CACHE_SMARTBACK:
			if (req->nr_sectors > 16)
				ctl_flags = 0x001F0004;
			else
				ctl_flags = 0x001F0010;
			break;
		case CACHE_SMARTTHROUGH:
			if (req->nr_sectors > 16)
				ctl_flags = 0x001F0004;
			else
				ctl_flags = 0x001F0010;
		default:
			break;
		}
	}

#ifdef CONFIG_I2O_EXT_ADAPTEC
	if (c->adaptec) {
		u8 cmd[10];
		u32 scsi_flags;
		u16 hwsec = queue_hardsect_size(req->q) >> KERNEL_SECTOR_SHIFT;

		memset(cmd, 0, 10);

		sgl_offset = SGL_OFFSET_12;