i2o_scsi.c

linux-2.6.15.6

 */
static void i2o_scsi_notify_device_remove(struct i2o_device *i2o_dev)
{
	switch (i2o_dev->lct_data.class_id) {
	case I2O_CLASS_EXECUTIVE:
	case I2O_CLASS_RANDOM_BLOCK_STORAGE:
		i2o_scsi_remove(&i2o_dev->device);
		break;

	default:
		break;
	}
};

/**
 *	i2o_scsi_notify_controller_add - Retrieve notifications of added
 *					 controllers
 *	@c: the controller which was added
 *
 *	If a I2O controller is added, we catch the notification to add a
 *	corresponding Scsi_Host.
 */
static void i2o_scsi_notify_controller_add(struct i2o_controller *c)
{
	struct i2o_scsi_host *i2o_shost;
	int rc;

	i2o_shost = i2o_scsi_host_alloc(c);
	if (IS_ERR(i2o_shost)) {
		osm_err("Could not initialize SCSI host\n");
		return;
	}

	rc = scsi_add_host(i2o_shost->scsi_host, &c->device);
	if (rc) {
		osm_err("Could not add SCSI host\n");
		scsi_host_put(i2o_shost->scsi_host);
		return;
	}

	c->driver_data[i2o_scsi_driver.context] = i2o_shost;

	osm_debug("new I2O SCSI host added\n");
};

/**
 *	i2o_scsi_notify_controller_remove - Retrieve notifications of removed
 *					    controllers
 *	@c: the controller which was removed
 *
 *	If a I2O controller is removed, we catch the notification to remove the
 *	corresponding Scsi_Host.
 */
static void i2o_scsi_notify_controller_remove(struct i2o_controller *c)
{
	struct i2o_scsi_host *i2o_shost;
	i2o_shost = i2o_scsi_get_host(c);
	if (!i2o_shost)
		return;

	c->driver_data[i2o_scsi_driver.context] = NULL;

	scsi_remove_host(i2o_shost->scsi_host);
	scsi_host_put(i2o_shost->scsi_host);
	osm_debug("I2O SCSI host removed\n");
};

/* SCSI OSM driver struct */
static struct i2o_driver i2o_scsi_driver = {
	.name = OSM_NAME,
	.reply = i2o_scsi_reply,
	.classes = i2o_scsi_class_id,
	.notify_device_add = i2o_scsi_notify_device_add,
	.notify_device_remove = i2o_scsi_notify_device_remove,
	.notify_controller_add = i2o_scsi_notify_controller_add,
	.notify_controller_remove = i2o_scsi_notify_controller_remove,
	.driver = {
		   .probe = i2o_scsi_probe,
		   .remove = i2o_scsi_remove,
		   },
};

/**
 *	i2o_scsi_queuecommand - queue a SCSI command
 *	@SCpnt: scsi command pointer
 *	@done: callback for completion
 *
 *	Issue a scsi command asynchronously. Return 0 on success or 1 if
 *	we hit an error (normally message queue congestion). The only
 *	minor complication here is that I2O deals with the device addressing
 *	so we have to map the bus/dev/lun back to an I2O handle as well
 *	as faking absent devices ourself.
 *
 *	Locks: takes the controller lock on error path only
 */

static int i2o_scsi_queuecommand(struct scsi_cmnd *SCpnt,
				 void (*done) (struct scsi_cmnd *))
{
	struct i2o_controller *c;
	struct i2o_device *i2o_dev;
	int tid;
	struct i2o_message __iomem *msg;
	u32 m;
	/*
	 * ENABLE_DISCONNECT
	 * SIMPLE_TAG
	 * RETURN_SENSE_DATA_IN_REPLY_MESSAGE_FRAME
	 */
	u32 scsi_flags = 0x20a00000;
	u32 sgl_offset;
	u32 __iomem *mptr;
	u32 cmd = I2O_CMD_SCSI_EXEC << 24;
	int rc = 0;

	/*
	 *      Do the incoming paperwork
	 */
	i2o_dev = SCpnt->device->hostdata;
	c = i2o_dev->iop;

	SCpnt->scsi_done = done;

	if (unlikely(!i2o_dev)) {
		osm_warn("no I2O device in request\n");
		SCpnt->result = DID_NO_CONNECT << 16;
		done(SCpnt);
		goto exit;
	}

	tid = i2o_dev->lct_data.tid;

	osm_debug("qcmd: Tid = %03x\n", tid);
	osm_debug("Real scsi messages.\n");

	/*
	 *      Put together a scsi execscb message
	 */
	switch (SCpnt->sc_data_direction) {
	case PCI_DMA_NONE:
		/* DATA NO XFER */
		sgl_offset = SGL_OFFSET_0;
		break;

	case PCI_DMA_TODEVICE:
		/* DATA OUT (iop-->dev) */
		scsi_flags |= 0x80000000;
		sgl_offset = SGL_OFFSET_10;
		break;

	case PCI_DMA_FROMDEVICE:
		/* DATA IN  (iop<--dev) */
		scsi_flags |= 0x40000000;
		sgl_offset = SGL_OFFSET_10;
		break;

	default:
		/* Unknown - kill the command */
		SCpnt->result = DID_NO_CONNECT << 16;
		done(SCpnt);
		goto exit;
	}

	/*
	 *      Obtain an I2O message. If there are none free then
	 *      throw it back to the scsi layer
	 */

	m = i2o_msg_get_wait(c, &msg, I2O_TIMEOUT_MESSAGE_GET);
	if (m == I2O_QUEUE_EMPTY) {
		rc = SCSI_MLQUEUE_HOST_BUSY;
		goto exit;
	}

	mptr = &msg->body[0];

#ifdef CONFIG_I2O_EXT_ADAPTEC
	if (c->adaptec) {
		u32 adpt_flags = 0;

		if (SCpnt->sc_request && SCpnt->sc_request->upper_private_data) {
			i2o_sg_io_hdr_t __user *usr_ptr =
			    ((Sg_request *) (SCpnt->sc_request->
					     upper_private_data))->header.
			    usr_ptr;

			if (usr_ptr)
				get_user(adpt_flags, &usr_ptr->flags);
		}

		switch (i2o_dev->lct_data.class_id) {
		case I2O_CLASS_EXECUTIVE:
		case I2O_CLASS_RANDOM_BLOCK_STORAGE:
			/* interpret flag has to be set for executive */
			adpt_flags ^= I2O_DPT_SG_FLAG_INTERPRET;
			break;

		default:
			break;
		}

		/*
		 * for Adaptec controllers we use the PRIVATE command, because
		 * the normal SCSI EXEC doesn't support all SCSI commands on
		 * all controllers (for example READ CAPACITY).
		 */
		if (sgl_offset == SGL_OFFSET_10)
			sgl_offset = SGL_OFFSET_12;
		cmd = I2O_CMD_PRIVATE << 24;
		writel(I2O_VENDOR_DPT << 16 | I2O_CMD_SCSI_EXEC, mptr++);
		writel(adpt_flags | tid, mptr++);
	}
#endif

	writel(cmd | HOST_TID << 12 | tid, &msg->u.head[1]);
	writel(i2o_scsi_driver.context, &msg->u.s.icntxt);

	/* We want the SCSI control block back */
	writel(i2o_cntxt_list_add(c, SCpnt), &msg->u.s.tcntxt);

	/* LSI_920_PCI_QUIRK
	 *
	 *      Intermittant observations of msg frame word data corruption
	 *      observed on msg[4] after:
	 *        WRITE, READ-MODIFY-WRITE
	 *      operations.  19990606 -sralston
	 *
	 *      (Hence we build this word via tag. Its good practice anyway
	 *       we don't want fetches over PCI needlessly)
	 */

	/* Attach tags to the devices */
	/* FIXME: implement
	   if(SCpnt->device->tagged_supported) {
	   if(SCpnt->tag == HEAD_OF_QUEUE_TAG)
	   scsi_flags |= 0x01000000;
	   else if(SCpnt->tag == ORDERED_QUEUE_TAG)
	   scsi_flags |= 0x01800000;
	   }
	 */

	writel(scsi_flags | SCpnt->cmd_len, mptr++);

	/* Write SCSI command into the message - always 16 byte block */
	memcpy_toio(mptr, SCpnt->cmnd, 16);
	mptr += 4;

	if (sgl_offset != SGL_OFFSET_0) {
		/* write size of data addressed by SGL */
		writel(SCpnt->request_bufflen, mptr++);

		/* Now fill in the SGList and command */
		if (SCpnt->use_sg) {
			if (!i2o_dma_map_sg(c, SCpnt->request_buffer,
					    SCpnt->use_sg,
					    SCpnt->sc_data_direction, &mptr))
				goto nomem;
		} else {
			SCpnt->SCp.dma_handle =
			    i2o_dma_map_single(c, SCpnt->request_buffer,
					       SCpnt->request_bufflen,
					       SCpnt->sc_data_direction, &mptr);
			if (dma_mapping_error(SCpnt->SCp.dma_handle))
				goto nomem;
		}
	}

	/* Stick the headers on */
	writel(I2O_MESSAGE_SIZE(mptr - &msg->u.head[0]) | sgl_offset,
	       &msg->u.head[0]);

	/* Queue the message */
	i2o_msg_post(c, m);

	osm_debug("Issued %ld\n", SCpnt->serial_number);

	return 0;

      nomem:
	rc = -ENOMEM;
	i2o_msg_nop(c, m);

      exit:
	return rc;
};

/**
 *	i2o_scsi_abort - abort a running command
 *	@SCpnt: command to abort
 *
 *	Ask the I2O controller to abort a command. This is an asynchrnous
 *	process and our callback handler will see the command complete with an
 *	aborted message if it succeeds.
 *
 *	Returns 0 if the command is successfully aborted or negative error code
 *	on failure.
 */
static int i2o_scsi_abort(struct scsi_cmnd *SCpnt)
{
	struct i2o_device *i2o_dev;
	struct i2o_controller *c;
	struct i2o_message __iomem *msg;
	u32 m;
	int tid;
	int status = FAILED;

	osm_warn("Aborting command block.\n");

	i2o_dev = SCpnt->device->hostdata;
	c = i2o_dev->iop;
	tid = i2o_dev->lct_data.tid;

	m = i2o_msg_get_wait(c, &msg, I2O_TIMEOUT_MESSAGE_GET);
	if (m == I2O_QUEUE_EMPTY)
		return SCSI_MLQUEUE_HOST_BUSY;

	writel(FIVE_WORD_MSG_SIZE | SGL_OFFSET_0, &msg->u.head[0]);
	writel(I2O_CMD_SCSI_ABORT << 24 | HOST_TID << 12 | tid,
	       &msg->u.head[1]);
	writel(i2o_cntxt_list_get_ptr(c, SCpnt), &msg->body[0]);

	if (!i2o_msg_post_wait(c, msg, I2O_TIMEOUT_SCSI_SCB_ABORT))
		status = SUCCESS;

	return status;
}

/**
 *	i2o_scsi_bios_param	-	Invent disk geometry
 *	@sdev: scsi device
 *	@dev: block layer device
 *	@capacity: size in sectors
 *	@ip: geometry array
 *
 *	This is anyones guess quite frankly. We use the same rules everyone
 *	else appears to and hope. It seems to work.
 */

static int i2o_scsi_bios_param(struct scsi_device *sdev,
			       struct block_device *dev, sector_t capacity,
			       int *ip)
{
	int size;

	size = capacity;
	ip[0] = 64;		/* heads                        */
	ip[1] = 32;		/* sectors                      */
	if ((ip[2] = size >> 11) > 1024) {	/* cylinders, test for big disk */
		ip[0] = 255;	/* heads                        */
		ip[1] = 63;	/* sectors                      */
		ip[2] = size / (255 * 63);	/* cylinders                    */
	}
	return 0;
}

static struct scsi_host_template i2o_scsi_host_template = {
	.proc_name = OSM_NAME,
	.name = OSM_DESCRIPTION,
	.info = i2o_scsi_info,
	.queuecommand = i2o_scsi_queuecommand,
	.eh_abort_handler = i2o_scsi_abort,
	.bios_param = i2o_scsi_bios_param,
	.can_queue = I2O_SCSI_CAN_QUEUE,
	.sg_tablesize = 8,
	.cmd_per_lun = 6,
	.use_clustering = ENABLE_CLUSTERING,
};

/**
 *	i2o_scsi_init - SCSI OSM initialization function
 *
 *	Register SCSI OSM into I2O core.
 *
 *	Returns 0 on success or negative error code on failure.
 */
static int __init i2o_scsi_init(void)
{
	int rc;

	printk(KERN_INFO OSM_DESCRIPTION " v" OSM_VERSION "\n");

	/* Register SCSI OSM into I2O core */
	rc = i2o_driver_register(&i2o_scsi_driver);
	if (rc) {
		osm_err("Could not register SCSI driver\n");
		return rc;
	}

	return 0;
};

/**
 *	i2o_scsi_exit - SCSI OSM exit function
 *
 *	Unregisters SCSI OSM from I2O core.
 */
static void __exit i2o_scsi_exit(void)
{
	/* Unregister I2O SCSI OSM from I2O core */
	i2o_driver_unregister(&i2o_scsi_driver);
};

MODULE_AUTHOR("Red Hat Software");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION(OSM_DESCRIPTION);
MODULE_VERSION(OSM_VERSION);

module_init(i2o_scsi_init);
module_exit(i2o_scsi_exit);