text: /* -*- linux-c -*-
   *  drivers/cdrom/viocd.c
   *
   *  iSeries Virtual CD Rom
   *
   *  Authors: Dave Boutcher <boutcher@us.ibm.com>
   *           Ryan Arnold <ryanarn@us.ibm.com>
   *           Colin Devilbiss <devilbis@us.ibm.com>
   *           Stephen Rothwell <sfr@au1.ibm.com>
   *
   * (C) Copyright 2000-2004 IBM Corporation
   *
   * This program is free software;  you can redistribute it and/or
   * modify it under the terms of the GNU General Public License as
   * published by the Free Software Foundation; either version 2 of the
   * License, or (at your option) anyu later version.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software Foundation,
   * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
   *
   * This routine provides access to CD ROM drives owned and managed by an
   * OS/400 partition running on the same box as this Linux partition.
   *
   * All operations are performed by sending messages back and forth to
   * the OS/400 partition.
   */
  
  #include <linux/major.h>
  #include <linux/blkdev.h>
  #include <linux/cdrom.h>
  #include <linux/errno.h>
  #include <linux/init.h>
  #include <linux/dma-mapping.h>
  #include <linux/module.h>
  #include <linux/completion.h>
  #include <linux/proc_fs.h>
  #include <linux/seq_file.h>
  
  #include <asm/vio.h>
  #include <asm/scatterlist.h>
  #include <asm/iseries/hv_types.h>
  #include <asm/iseries/hv_lp_event.h>
  #include <asm/iseries/vio.h>
  #include <asm/firmware.h>
  
  #define VIOCD_DEVICE			"iseries/vcd"
  
  #define VIOCD_VERS "1.06"
  
  #define VIOCD_KERN_WARNING		KERN_WARNING "viocd: "
  #define VIOCD_KERN_INFO			KERN_INFO "viocd: "
  
  struct viocdlpevent {
  	struct HvLpEvent	event;
  	u32			reserved;
  	u16			version;
  	u16			sub_result;
  	u16			disk;
  	u16			flags;
  	u32			token;
  	u64			offset;		/* On open, max number of disks */
  	u64			len;		/* On open, size of the disk */
  	u32			block_size;	/* Only set on open */
  	u32			media_size;	/* Only set on open */
  };
  
  enum viocdsubtype {
  	viocdopen = 0x0001,
  	viocdclose = 0x0002,
  	viocdread = 0x0003,
  	viocdwrite = 0x0004,
  	viocdlockdoor = 0x0005,
  	viocdgetinfo = 0x0006,
  	viocdcheck = 0x0007
  };
  
  /*
   * Should probably make this a module parameter....sigh
   */
  #define VIOCD_MAX_CD	HVMAXARCHITECTEDVIRTUALCDROMS
  
  static const struct vio_error_entry viocd_err_table[] = {
  	{0x0201, EINVAL, "Invalid Range"},
  	{0x0202, EINVAL, "Invalid Token"},
  	{0x0203, EIO, "DMA Error"},
  	{0x0204, EIO, "Use Error"},
  	{0x0205, EIO, "Release Error"},
  	{0x0206, EINVAL, "Invalid CD"},
  	{0x020C, EROFS, "Read Only Device"},
  	{0x020D, ENOMEDIUM, "Changed or Missing Volume (or Varied Off?)"},
  	{0x020E, EIO, "Optical System Error (Varied Off?)"},
  	{0x02FF, EIO, "Internal Error"},
  	{0x3010, EIO, "Changed Volume"},
  	{0xC100, EIO, "Optical System Error"},
  	{0x0000, 0, NULL},
  };
  
  /*
   * This is the structure we use to exchange info between driver and interrupt
   * handler
   */
  struct viocd_waitevent {
  	struct completion	com;
  	int			rc;
  	u16			sub_result;
  	int			changed;
  };
  
  /* this is a lookup table for the true capabilities of a device */
  struct capability_entry {
  	char	*type;
  	int	capability;
  };
  
  static struct capability_entry capability_table[] __initdata = {
  	{ "6330", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
  	{ "6331", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
  	{ "6333", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
  	{ "632A", CDC_LOCK | CDC_DVD_RAM | CDC_RAM },
  	{ "6321", CDC_LOCK },
  	{ "632B", 0 },
  	{ NULL  , CDC_LOCK },
  };
  
  /* These are our internal structures for keeping track of devices */
  static int viocd_numdev;
  
  struct cdrom_info {
  	char	rsrcname[10];
  	char	type[4];
  	char	model[3];
  };
  /*
   * This needs to be allocated since it is passed to the
   * Hypervisor and we may be a module.
   */
  static struct cdrom_info *viocd_unitinfo;
  static dma_addr_t unitinfo_dmaaddr;
  
  struct disk_info {
  	struct gendisk			*viocd_disk;
  	struct cdrom_device_info	viocd_info;
  	struct device			*dev;
  };
  static struct disk_info viocd_diskinfo[VIOCD_MAX_CD];
  
  #define DEVICE_NR(di)	((di) - &viocd_diskinfo[0])
  
  static spinlock_t viocd_reqlock;
  
  #define MAX_CD_REQ	1
  
  /* procfs support */
  static int proc_viocd_show(struct seq_file *m, void *v)
  {
  	int i;
  
  	for (i = 0; i < viocd_numdev; i++) {
  		seq_printf(m, "viocd device %d is iSeries resource %10.10s"
  				"type %4.4s, model %3.3s\n",
  				i, viocd_unitinfo[i].rsrcname,
  				viocd_unitinfo[i].type,
  				viocd_unitinfo[i].model);
  	}
  	return 0;
  }
  
  static int proc_viocd_open(struct inode *inode, struct file *file)
  {
  	return single_open(file, proc_viocd_show, NULL);
  }
  
  static const struct file_operations proc_viocd_operations = {
  	.open		= proc_viocd_open,
  	.read		= seq_read,
  	.llseek		= seq_lseek,
  	.release	= single_release,
  };
  
  static int viocd_blk_open(struct inode *inode, struct file *file)
  {
  	struct disk_info *di = inode->i_bdev->bd_disk->private_data;
  	return cdrom_open(&di->viocd_info, inode, file);
  }
  
  static int viocd_blk_release(struct inode *inode, struct file *file)
  {
  	struct disk_info *di = inode->i_bdev->bd_disk->private_data;
  	return cdrom_release(&di->viocd_info, file);
  }
  
  static int viocd_blk_ioctl(struct inode *inode, struct file *file,
  		unsigned cmd, unsigned long arg)
  {
  	struct disk_info *di = inode->i_bdev->bd_disk->private_data;
  	return cdrom_ioctl(file, &di->viocd_info, inode, cmd, arg);
  }
  
  static int viocd_blk_media_changed(struct gendisk *disk)
  {
  	struct disk_info *di = disk->private_data;
  	return cdrom_media_changed(&di->viocd_info);
  }
  
  struct block_device_operations viocd_fops = {
  	.owner =		THIS_MODULE,
  	.open =			viocd_blk_open,
  	.release =		viocd_blk_release,
  	.ioctl =		viocd_blk_ioctl,
  	.media_changed =	viocd_blk_media_changed,
  };
  
  /* Get info on CD devices from OS/400 */
  static void __init get_viocd_info(void)
  {
  	HvLpEvent_Rc hvrc;
  	int i;
  	struct viocd_waitevent we;
  
  	viocd_unitinfo = dma_alloc_coherent(iSeries_vio_dev,
  			sizeof(*viocd_unitinfo) * VIOCD_MAX_CD,
  			&unitinfo_dmaaddr, GFP_ATOMIC);
  	if (viocd_unitinfo == NULL) {
  		printk(VIOCD_KERN_WARNING "error allocating unitinfo\n");
  		return;
  	}
  
  	memset(viocd_unitinfo, 0, sizeof(*viocd_unitinfo) * VIOCD_MAX_CD);
  
  	init_completion(&we.com);
  
  	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
  			HvLpEvent_Type_VirtualIo,
  			viomajorsubtype_cdio | viocdgetinfo,
  			HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
  			viopath_sourceinst(viopath_hostLp),
  			viopath_targetinst(viopath_hostLp),
  			(u64)&we, VIOVERSION << 16, unitinfo_dmaaddr, 0,
  			sizeof(*viocd_unitinfo) * VIOCD_MAX_CD, 0);
  	if (hvrc != HvLpEvent_Rc_Good) {
  		printk(VIOCD_KERN_WARNING "cdrom error sending event. rc %d\n",
  				(int)hvrc);
  		goto error_ret;
  	}
  
  	wait_for_completion(&we.com);
  
  	if (we.rc) {
  		const struct vio_error_entry *err =
  			vio_lookup_rc(viocd_err_table, we.sub_result);
  		printk(VIOCD_KERN_WARNING "bad rc %d:0x%04X on getinfo: %s\n",
  				we.rc, we.sub_result, err->msg);
  		goto error_ret;
  	}
  
  	for (i = 0; (i < VIOCD_MAX_CD) && viocd_unitinfo[i].rsrcname[0]; i++)
  		viocd_numdev++;
  
  error_ret:
  	if (viocd_numdev == 0) {
  		dma_free_coherent(iSeries_vio_dev,
  				sizeof(*viocd_unitinfo) * VIOCD_MAX_CD,
  				viocd_unitinfo, unitinfo_dmaaddr);
  		viocd_unitinfo = NULL;
  	}
  }
  
  static int viocd_open(struct cdrom_device_info *cdi, int purpose)
  {
          struct disk_info *diskinfo = cdi->handle;
  	int device_no = DEVICE_NR(diskinfo);
  	HvLpEvent_Rc hvrc;
  	struct viocd_waitevent we;
  
  	init_completion(&we.com);
  	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
  			HvLpEvent_Type_VirtualIo,
  			viomajorsubtype_cdio | viocdopen,
  			HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
  			viopath_sourceinst(viopath_hostLp),
  			viopath_targetinst(viopath_hostLp),
  			(u64)&we, VIOVERSION << 16, ((u64)device_no << 48),
  			0, 0, 0);
  	if (hvrc != 0) {
  		printk(VIOCD_KERN_WARNING
  				"bad rc on HvCallEvent_signalLpEventFast %d\n",
  				(int)hvrc);
  		return -EIO;
  	}
  
  	wait_for_completion(&we.com);
  
  	if (we.rc) {
  		const struct vio_error_entry *err =
  			vio_lookup_rc(viocd_err_table, we.sub_result);
  		printk(VIOCD_KERN_WARNING "bad rc %d:0x%04X on open: %s\n",
  				we.rc, we.sub_result, err->msg);
  		return -err->errno;
  	}
  
  	return 0;
  }
  
  static void viocd_release(struct cdrom_device_info *cdi)
  {
  	int device_no = DEVICE_NR((struct disk_info *)cdi->handle);
  	HvLpEvent_Rc hvrc;
  
  	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
  			HvLpEvent_Type_VirtualIo,
  			viomajorsubtype_cdio | viocdclose,
  			HvLpEvent_AckInd_NoAck, HvLpEvent_AckType_ImmediateAck,
  			viopath_sourceinst(viopath_hostLp),
  			viopath_targetinst(viopath_hostLp), 0,
  			VIOVERSION << 16, ((u64)device_no << 48), 0, 0, 0);
  	if (hvrc != 0)
  		printk(VIOCD_KERN_WARNING
  				"bad rc on HvCallEvent_signalLpEventFast %d\n",
  				(int)hvrc);
  }
  
  /* Send a read or write request to OS/400 */
  static int send_request(struct request *req)
  {
  	HvLpEvent_Rc hvrc;
  	struct disk_info *diskinfo = req->rq_disk->private_data;
  	u64 len;
  	dma_addr_t dmaaddr;
  	int direction;
  	u16 cmd;
  	struct scatterlist sg;
  
  	BUG_ON(req->nr_phys_segments > 1);
  
  	if (rq_data_dir(req) == READ) {
  		direction = DMA_FROM_DEVICE;
  		cmd = viomajorsubtype_cdio | viocdread;
  	} else {
  		direction = DMA_TO_DEVICE;
  		cmd = viomajorsubtype_cdio | viocdwrite;
  	}
  
          if (blk_rq_map_sg(req->q, req, &sg) == 0) {
  		printk(VIOCD_KERN_WARNING
  				"error setting up scatter/gather list\n");
  		return -1;
  	}
  
  	if (dma_map_sg(diskinfo->dev, &sg, 1, direction) == 0) {
  		printk(VIOCD_KERN_WARNING "error allocating sg tce\n");
  		return -1;
  	}
  	dmaaddr = sg_dma_address(&sg);
  	len = sg_dma_len(&sg);
  
  	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
  			HvLpEvent_Type_VirtualIo, cmd,
  			HvLpEvent_AckInd_DoAck,
  			HvLpEvent_AckType_ImmediateAck,
  			viopath_sourceinst(viopath_hostLp),
  			viopath_targetinst(viopath_hostLp),
  			(u64)req, VIOVERSION << 16,
  			((u64)DEVICE_NR(diskinfo) << 48) | dmaaddr,
  			(u64)req->sector * 512, len, 0);
  	if (hvrc != HvLpEvent_Rc_Good) {
  		printk(VIOCD_KERN_WARNING "hv error on op %d\n", (int)hvrc);
  		return -1;
  	}
  
  	return 0;
  }
  
  static void viocd_end_request(struct request *req, int uptodate)
  {
  	int nsectors = req->hard_nr_sectors;
  
  	/*
  	 * Make sure it's fully ended, and ensure that we process
  	 * at least one sector.
  	 */
  	if (blk_pc_request(req))
  		nsectors = (req->data_len + 511) >> 9;
  	if (!nsectors)
  		nsectors = 1;
  
  	if (end_that_request_first(req, uptodate, nsectors))
  		BUG();
  	add_disk_randomness(req->rq_disk);
  	blkdev_dequeue_request(req);
  	end_that_request_last(req, uptodate);
  }
  
  static int rwreq;
  
  static void do_viocd_request(request_queue_t *q)
  {
  	struct request *req;
  
  	while ((rwreq == 0) && ((req = elv_next_request(q)) != NULL)) {
  		if (!blk_fs_request(req))
  			viocd_end_request(req, 0);
  		else if (send_request(req) < 0) {
  			printk(VIOCD_KERN_WARNING
  					"unable to send message to OS/400!");
  			viocd_end_request(req, 0);
  		} else
  			rwreq++;
  	}
  }
  
  static int viocd_media_changed(struct cdrom_device_info *cdi, int disc_nr)
  {
  	struct viocd_waitevent we;
  	HvLpEvent_Rc hvrc;
  	int device_no = DEVICE_NR((struct disk_info *)cdi->handle);
  
  	init_completion(&we.com);
  
  	/* Send the open event to OS/400 */
  	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
  			HvLpEvent_Type_VirtualIo,
  			viomajorsubtype_cdio | viocdcheck,
  			HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
  			viopath_sourceinst(viopath_hostLp),
  			viopath_targetinst(viopath_hostLp),
  			(u64)&we, VIOVERSION << 16, ((u64)device_no << 48),
  			0, 0, 0);
  	if (hvrc != 0) {
  		printk(VIOCD_KERN_WARNING "bad rc on HvCallEvent_signalLpEventFast %d\n",
  				(int)hvrc);
  		return -EIO;
  	}
  
  	wait_for_completion(&we.com);
  
  	/* Check the return code.  If bad, assume no change */
  	if (we.rc) {
  		const struct vio_error_entry *err =
  			vio_lookup_rc(viocd_err_table, we.sub_result);
  		printk(VIOCD_KERN_WARNING
  				"bad rc %d:0x%04X on check_change: %s; Assuming no change\n",
  				we.rc, we.sub_result, err->msg);
  		return 0;
  	}
  
  	return we.changed;
  }
  
  static int viocd_lock_door(struct cdrom_device_info *cdi, int locking)
  {
  	HvLpEvent_Rc hvrc;
  	u64 device_no = DEVICE_NR((struct disk_info *)cdi->handle);
  	/* NOTE: flags is 1 or 0 so it won't overwrite the device_no */
  	u64 flags = !!locking;
  	struct viocd_waitevent we;
  
  	init_completion(&we.com);
  
  	/* Send the lockdoor event to OS/400 */
  	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
  			HvLpEvent_Type_VirtualIo,
  			viomajorsubtype_cdio | viocdlockdoor,
  			HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
  			viopath_sourceinst(viopath_hostLp),
  			viopath_targetinst(viopath_hostLp),
  			(u64)&we, VIOVERSION << 16,
  			(device_no << 48) | (flags << 32), 0, 0, 0);
  	if (hvrc != 0) {
  		printk(VIOCD_KERN_WARNING "bad rc on HvCallEvent_signalLpEventFast %d\n",
  				(int)hvrc);
  		return -EIO;
  	}
  
  	wait_for_completion(&we.com);
  
  	if (we.rc != 0)
  		return -EIO;
  	return 0;
  }
  
  static int viocd_packet(struct cdrom_device_info *cdi,
  		struct packet_command *cgc)
  {
  	unsigned int buflen = cgc->buflen;
  	int ret = -EIO;
  
  	switch (cgc->cmd[0]) {
  	case GPCMD_READ_DISC_INFO:
  		{
  			disc_information *di = (disc_information *)cgc->buffer;
  
  			if (buflen >= 2) {
  				di->disc_information_length = cpu_to_be16(1);
  				ret = 0;
  			}
  			if (buflen >= 3)
  				di->erasable =
  					(cdi->ops->capability & ~cdi->mask
  					 & (CDC_DVD_RAM | CDC_RAM)) != 0;
  		}
  		break;
  	case GPCMD_GET_CONFIGURATION:
  		if (cgc->cmd[3] == CDF_RWRT) {
  			struct rwrt_feature_desc *rfd = (struct rwrt_feature_desc *)(cgc->buffer + sizeof(struct feature_header));
  
  			if ((buflen >=
  			     (sizeof(struct feature_header) + sizeof(*rfd))) &&
  			    (cdi->ops->capability & ~cdi->mask
  			     & (CDC_DVD_RAM | CDC_RAM))) {
  				rfd->feature_code = cpu_to_be16(CDF_RWRT);
  				rfd->curr = 1;
  				ret = 0;
  			}
  		}
  		break;
  	default:
  		if (cgc->sense) {
  			/* indicate Unknown code */
  			cgc->sense->sense_key = 0x05;
  			cgc->sense->asc = 0x20;
  			cgc->sense->ascq = 0x00;
  		}
  		break;
  	}
  
  	cgc->stat = ret;
  	return ret;
  }
  
  static void restart_all_queues(int first_index)
  {
  	int i;
  
  	for (i = first_index + 1; i < viocd_numdev; i++)
  		if (viocd_diskinfo[i].viocd_disk)
  			blk_run_queue(viocd_diskinfo[i].viocd_disk->queue);
  	for (i = 0; i <= first_index; i++)
  		if (viocd_diskinfo[i].viocd_disk)
  			blk_run_queue(viocd_diskinfo[i].viocd_disk->queue);
  }
  
  /* This routine handles incoming CD LP events */
  static void vio_handle_cd_event(struct HvLpEvent *event)
  {
  	struct viocdlpevent *bevent;
  	struct viocd_waitevent *pwe;
  	struct disk_info *di;
  	unsigned long flags;
  	struct request *req;
  
  
  	if (event == NULL)
  		/* Notification that a partition went away! */
  		return;
  	/* First, we should NEVER get an int here...only acks */
  	if (hvlpevent_is_int(event)) {
  		printk(VIOCD_KERN_WARNING
  				"Yikes! got an int in viocd event handler!\n");
  		if (hvlpevent_need_ack(event)) {
  			event->xRc = HvLpEvent_Rc_InvalidSubtype;
  			HvCallEvent_ackLpEvent(event);
  		}
  	}
  
  	bevent = (struct viocdlpevent *)event;
  
  	switch (event->xSubtype & VIOMINOR_SUBTYPE_MASK) {
  	case viocdopen:
  		if (event->xRc == 0) {
  			di = &viocd_diskinfo[bevent->disk];
  			blk_queue_hardsect_size(di->viocd_disk->queue,
  					bevent->block_size);
  			set_capacity(di->viocd_disk,
  					bevent->media_size *
  					bevent->block_size / 512);
  		}
  		/* FALLTHROUGH !! */
  	case viocdgetinfo:
  	case viocdlockdoor:
  		pwe = (struct viocd_waitevent *)event->xCorrelationToken;
  return_complete:
  		pwe->rc = event->xRc;
  		pwe->sub_result = bevent->sub_result;
  		complete(&pwe->com);
  		break;
  
  	case viocdcheck:
  		pwe = (struct viocd_waitevent *)event->xCorrelationToken;
  		pwe->changed = bevent->flags;
  		goto return_complete;
  
  	case viocdclose:
  		break;
  
  	case viocdwrite:
  	case viocdread:
  		/*
  		 * Since this is running in interrupt mode, we need to
  		 * make sure we're not stepping on any global I/O operations
  		 */
  		di = &viocd_diskinfo[bevent->disk];
  		spin_lock_irqsave(&viocd_reqlock, flags);
  		dma_unmap_single(di->dev, bevent->token, bevent->len,
  				((event->xSubtype & VIOMINOR_SUBTYPE_MASK) == viocdread)
  				?  DMA_FROM_DEVICE : DMA_TO_DEVICE);
  		req = (struct request *)bevent->event.xCorrelationToken;
  		rwreq--;
  
  		if (event->xRc != HvLpEvent_Rc_Good) {
  			const struct vio_error_entry *err =
  				vio_lookup_rc(viocd_err_table,
  						bevent->sub_result);
  			printk(VIOCD_KERN_WARNING "request %p failed "
  					"with rc %d:0x%04X: %s\n",
  					req, event->xRc,
  					bevent->sub_result, err->msg);
  			viocd_end_request(req, 0);
  		} else
  			viocd_end_request(req, 1);
  
  		/* restart handling of incoming requests */
  		spin_unlock_irqrestore(&viocd_reqlock, flags);
  		restart_all_queues(bevent->disk);
  		break;
  
  	default:
  		printk(VIOCD_KERN_WARNING
  				"message with invalid subtype %0x04X!\n",
  				event->xSubtype & VIOMINOR_SUBTYPE_MASK);
  		if (hvlpevent_need_ack(event)) {
  			event->xRc = HvLpEvent_Rc_InvalidSubtype;
  			HvCallEvent_ackLpEvent(event);
  		}
  	}
  }
  
  static struct cdrom_device_ops viocd_dops = {
  	.open = viocd_open,
  	.release = viocd_release,
  	.media_changed = viocd_media_changed,
  	.lock_door = viocd_lock_door,
  	.generic_packet = viocd_packet,
  	.capability = CDC_CLOSE_TRAY | CDC_OPEN_TRAY | CDC_LOCK | CDC_SELECT_SPEED | CDC_SELECT_DISC | CDC_MULTI_SESSION | CDC_MCN | CDC_MEDIA_CHANGED | CDC_PLAY_AUDIO | CDC_RESET | CDC_DRIVE_STATUS | CDC_GENERIC_PACKET | CDC_CD_R | CDC_CD_RW | CDC_DVD | CDC_DVD_R | CDC_DVD_RAM | CDC_RAM
  };
  
  static int __init find_capability(const char *type)
  {
  	struct capability_entry *entry;
  
  	for(entry = capability_table; entry->type; ++entry)
  		if(!strncmp(entry->type, type, 4))
  			break;
  	return entry->capability;
  }
  
  static int viocd_probe(struct vio_dev *vdev, const struct vio_device_id *id)
  {
  	struct gendisk *gendisk;
  	int deviceno;
  	struct disk_info *d;
  	struct cdrom_device_info *c;
  	struct cdrom_info *ci;
  	struct request_queue *q;
  
  	deviceno = vdev->unit_address;
  	if (deviceno >= viocd_numdev)
  		return -ENODEV;
  
  	d = &viocd_diskinfo[deviceno];
  	c = &d->viocd_info;
  	ci = &viocd_unitinfo[deviceno];
  
  	c->ops = &viocd_dops;
  	c->speed = 4;
  	c->capacity = 1;
  	c->handle = d;
  	c->mask = ~find_capability(ci->type);
  	sprintf(c->name, VIOCD_DEVICE "%c", 'a' + deviceno);
  
  	if (register_cdrom(c) != 0) {
  		printk(VIOCD_KERN_WARNING "Cannot register viocd CD-ROM %s!\n",
  				c->name);
  		goto out;
  	}
  	printk(VIOCD_KERN_INFO "cd %s is iSeries resource %10.10s "
  			"type %4.4s, model %3.3s\n",
  			c->name, ci->rsrcname, ci->type, ci->model);
  	q = blk_init_queue(do_viocd_request, &viocd_reqlock);
  	if (q == NULL) {
  		printk(VIOCD_KERN_WARNING "Cannot allocate queue for %s!\n",
  				c->name);
  		goto out_unregister_cdrom;
  	}
  	gendisk = alloc_disk(1);
  	if (gendisk == NULL) {
  		printk(VIOCD_KERN_WARNING "Cannot create gendisk for %s!\n",
  				c->name);
  		goto out_cleanup_queue;
  	}
  	gendisk->major = VIOCD_MAJOR;
  	gendisk->first_minor = deviceno;
  	strncpy(gendisk->disk_name, c->name,
  			sizeof(gendisk->disk_name));
  	blk_queue_max_hw_segments(q, 1);
  	blk_queue_max_phys_segments(q, 1);
  	blk_queue_max_sectors(q, 4096 / 512);
  	gendisk->queue = q;
  	gendisk->fops = &viocd_fops;
  	gendisk->flags = GENHD_FL_CD|GENHD_FL_REMOVABLE;
  	set_capacity(gendisk, 0);
  	gendisk->private_data = d;
  	d->viocd_disk = gendisk;
  	d->dev = &vdev->dev;
  	gendisk->driverfs_dev = d->dev;
  	add_disk(gendisk);
  	return 0;
  
  out_cleanup_queue:
  	blk_cleanup_queue(q);
  out_unregister_cdrom:
  	unregister_cdrom(c);
  out:
  	return -ENODEV;
  }
  
  static int viocd_remove(struct vio_dev *vdev)
  {
  	struct disk_info *d = &viocd_diskinfo[vdev->unit_address];
  
  	if (unregister_cdrom(&d->viocd_info) != 0)
  		printk(VIOCD_KERN_WARNING
  				"Cannot unregister viocd CD-ROM %s!\n",
  				d->viocd_info.name);
  	del_gendisk(d->viocd_disk);
  	blk_cleanup_queue(d->viocd_disk->queue);
  	put_disk(d->viocd_disk);
  	return 0;
  }
  
  /**
   * viocd_device_table: Used by vio.c to match devices that we
   * support.
   */
  static struct vio_device_id viocd_device_table[] __devinitdata = {
  	{ "block", "IBM,iSeries-viocd" },
  	{ "", "" }
  };
  MODULE_DEVICE_TABLE(vio, viocd_device_table);
  
  static struct vio_driver viocd_driver = {
  	.id_table = viocd_device_table,
  	.probe = viocd_probe,
  	.remove = viocd_remove,
  	.driver = {
  		.name = "viocd",
  		.owner = THIS_MODULE,
  	}
  };
  
  static int __init viocd_init(void)
  {
  	struct proc_dir_entry *e;
  	int ret = 0;
  
  	if (!firmware_has_feature(FW_FEATURE_ISERIES))
  		return -ENODEV;
  
  	if (viopath_hostLp == HvLpIndexInvalid) {
  		vio_set_hostlp();
  		/* If we don't have a host, bail out */
  		if (viopath_hostLp == HvLpIndexInvalid)
  			return -ENODEV;
  	}
  
  	printk(VIOCD_KERN_INFO "vers " VIOCD_VERS ", hosting partition %d\n",
  			viopath_hostLp);
  
  	if (register_blkdev(VIOCD_MAJOR, VIOCD_DEVICE) != 0) {
  		printk(VIOCD_KERN_WARNING "Unable to get major %d for %s\n",
  				VIOCD_MAJOR, VIOCD_DEVICE);
  		return -EIO;
  	}
  
  	ret = viopath_open(viopath_hostLp, viomajorsubtype_cdio,
  			MAX_CD_REQ + 2);
  	if (ret) {
  		printk(VIOCD_KERN_WARNING
  				"error opening path to host partition %d\n",
  				viopath_hostLp);
  		goto out_unregister;
  	}
  
  	/* Initialize our request handler */
  	vio_setHandler(viomajorsubtype_cdio, vio_handle_cd_event);
  
  	get_viocd_info();
  
  	spin_lock_init(&viocd_reqlock);
  
  	ret = vio_register_driver(&viocd_driver);
  	if (ret)
  		goto out_free_info;
  
  	e = create_proc_entry("iSeries/viocd", S_IFREG|S_IRUGO, NULL);
  	if (e) {
  		e->owner = THIS_MODULE;
  		e->proc_fops = &proc_viocd_operations;
  	}
  
  	return 0;
  
  out_free_info:
  	dma_free_coherent(iSeries_vio_dev,
  			sizeof(*viocd_unitinfo) * VIOCD_MAX_CD,
  			viocd_unitinfo, unitinfo_dmaaddr);
  	vio_clearHandler(viomajorsubtype_cdio);
  	viopath_close(viopath_hostLp, viomajorsubtype_cdio, MAX_CD_REQ + 2);
  out_unregister:
  	unregister_blkdev(VIOCD_MAJOR, VIOCD_DEVICE);
  	return ret;
  }
  
  static void __exit viocd_exit(void)
  {
  	remove_proc_entry("iSeries/viocd", NULL);
  	vio_unregister_driver(&viocd_driver);
  	if (viocd_unitinfo != NULL)
  		dma_free_coherent(iSeries_vio_dev,
  				sizeof(*viocd_unitinfo) * VIOCD_MAX_CD,
  				viocd_unitinfo, unitinfo_dmaaddr);
  	viopath_close(viopath_hostLp, viomajorsubtype_cdio, MAX_CD_REQ + 2);
  	vio_clearHandler(viomajorsubtype_cdio);
  	unregister_blkdev(VIOCD_MAJOR, VIOCD_DEVICE);
  }
  
  module_init(viocd_init);
  module_exit(viocd_exit);
  MODULE_LICENSE("GPL");
  