2 * drivers/cdrom/viocd.c
4 * iSeries Virtual CD Rom
6 * Authors: Dave Boutcher <boutcher@us.ibm.com>
7 * Ryan Arnold <ryanarn@us.ibm.com>
8 * Colin Devilbiss <devilbis@us.ibm.com>
9 * Stephen Rothwell <sfr@au1.ibm.com>
11 * (C) Copyright 2000-2004 IBM Corporation
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License as
15 * published by the Free Software Foundation; either version 2 of the
16 * License, or (at your option) anyu later version.
18 * This program is distributed in the hope that it will be useful, but
19 * WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
21 * General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software Foundation,
25 * Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
27 * This routine provides access to CD ROM drives owned and managed by an
28 * OS/400 partition running on the same box as this Linux partition.
30 * All operations are performed by sending messages back and forth to
31 * the OS/400 partition.
34 #include <linux/major.h>
35 #include <linux/blkdev.h>
36 #include <linux/cdrom.h>
37 #include <linux/errno.h>
38 #include <linux/init.h>
39 #include <linux/dma-mapping.h>
40 #include <linux/module.h>
41 #include <linux/completion.h>
42 #include <linux/proc_fs.h>
43 #include <linux/seq_file.h>
44 #include <linux/scatterlist.h>
47 #include <asm/iseries/hv_types.h>
48 #include <asm/iseries/hv_lp_event.h>
49 #include <asm/iseries/vio.h>
50 #include <asm/firmware.h>
52 #define VIOCD_DEVICE "iseries/vcd"
54 #define VIOCD_VERS "1.06"
56 #define VIOCD_KERN_WARNING KERN_WARNING "viocd: "
57 #define VIOCD_KERN_INFO KERN_INFO "viocd: "
60 * Should probably make this a module parameter....sigh
62 #define VIOCD_MAX_CD HVMAXARCHITECTEDVIRTUALCDROMS
64 static const struct vio_error_entry viocd_err_table
[] = {
65 {0x0201, EINVAL
, "Invalid Range"},
66 {0x0202, EINVAL
, "Invalid Token"},
67 {0x0203, EIO
, "DMA Error"},
68 {0x0204, EIO
, "Use Error"},
69 {0x0205, EIO
, "Release Error"},
70 {0x0206, EINVAL
, "Invalid CD"},
71 {0x020C, EROFS
, "Read Only Device"},
72 {0x020D, ENOMEDIUM
, "Changed or Missing Volume (or Varied Off?)"},
73 {0x020E, EIO
, "Optical System Error (Varied Off?)"},
74 {0x02FF, EIO
, "Internal Error"},
75 {0x3010, EIO
, "Changed Volume"},
76 {0xC100, EIO
, "Optical System Error"},
81 * This is the structure we use to exchange info between driver and interrupt
84 struct viocd_waitevent
{
85 struct completion com
;
91 /* this is a lookup table for the true capabilities of a device */
92 struct capability_entry
{
97 static struct capability_entry capability_table
[] __initdata
= {
98 { "6330", CDC_LOCK
| CDC_DVD_RAM
| CDC_RAM
},
99 { "6331", CDC_LOCK
| CDC_DVD_RAM
| CDC_RAM
},
100 { "6333", CDC_LOCK
| CDC_DVD_RAM
| CDC_RAM
},
101 { "632A", CDC_LOCK
| CDC_DVD_RAM
| CDC_RAM
},
102 { "6321", CDC_LOCK
},
107 /* These are our internal structures for keeping track of devices */
108 static int viocd_numdev
;
111 struct gendisk
*viocd_disk
;
112 struct cdrom_device_info viocd_info
;
114 const char *rsrcname
;
118 static struct disk_info viocd_diskinfo
[VIOCD_MAX_CD
];
120 #define DEVICE_NR(di) ((di) - &viocd_diskinfo[0])
122 static spinlock_t viocd_reqlock
;
127 static int proc_viocd_show(struct seq_file
*m
, void *v
)
131 for (i
= 0; i
< viocd_numdev
; i
++) {
132 seq_printf(m
, "viocd device %d is iSeries resource %10.10s"
133 "type %4.4s, model %3.3s\n",
134 i
, viocd_diskinfo
[i
].rsrcname
,
135 viocd_diskinfo
[i
].type
,
136 viocd_diskinfo
[i
].model
);
141 static int proc_viocd_open(struct inode
*inode
, struct file
*file
)
143 return single_open(file
, proc_viocd_show
, NULL
);
146 static const struct file_operations proc_viocd_operations
= {
147 .open
= proc_viocd_open
,
150 .release
= single_release
,
153 static int viocd_blk_open(struct inode
*inode
, struct file
*file
)
155 struct disk_info
*di
= inode
->i_bdev
->bd_disk
->private_data
;
156 return cdrom_open(&di
->viocd_info
, inode
, file
);
159 static int viocd_blk_release(struct inode
*inode
, struct file
*file
)
161 struct disk_info
*di
= inode
->i_bdev
->bd_disk
->private_data
;
162 return cdrom_release(&di
->viocd_info
, file
);
165 static int viocd_blk_ioctl(struct inode
*inode
, struct file
*file
,
166 unsigned cmd
, unsigned long arg
)
168 struct disk_info
*di
= inode
->i_bdev
->bd_disk
->private_data
;
169 return cdrom_ioctl(file
, &di
->viocd_info
, inode
, cmd
, arg
);
172 static int viocd_blk_media_changed(struct gendisk
*disk
)
174 struct disk_info
*di
= disk
->private_data
;
175 return cdrom_media_changed(&di
->viocd_info
);
178 struct block_device_operations viocd_fops
= {
179 .owner
= THIS_MODULE
,
180 .open
= viocd_blk_open
,
181 .release
= viocd_blk_release
,
182 .ioctl
= viocd_blk_ioctl
,
183 .media_changed
= viocd_blk_media_changed
,
186 static int viocd_open(struct cdrom_device_info
*cdi
, int purpose
)
188 struct disk_info
*diskinfo
= cdi
->handle
;
189 int device_no
= DEVICE_NR(diskinfo
);
191 struct viocd_waitevent we
;
193 init_completion(&we
.com
);
194 hvrc
= HvCallEvent_signalLpEventFast(viopath_hostLp
,
195 HvLpEvent_Type_VirtualIo
,
196 viomajorsubtype_cdio
| viocdopen
,
197 HvLpEvent_AckInd_DoAck
, HvLpEvent_AckType_ImmediateAck
,
198 viopath_sourceinst(viopath_hostLp
),
199 viopath_targetinst(viopath_hostLp
),
200 (u64
)&we
, VIOVERSION
<< 16, ((u64
)device_no
<< 48),
203 printk(VIOCD_KERN_WARNING
204 "bad rc on HvCallEvent_signalLpEventFast %d\n",
209 wait_for_completion(&we
.com
);
212 const struct vio_error_entry
*err
=
213 vio_lookup_rc(viocd_err_table
, we
.sub_result
);
214 printk(VIOCD_KERN_WARNING
"bad rc %d:0x%04X on open: %s\n",
215 we
.rc
, we
.sub_result
, err
->msg
);
222 static void viocd_release(struct cdrom_device_info
*cdi
)
224 int device_no
= DEVICE_NR((struct disk_info
*)cdi
->handle
);
227 hvrc
= HvCallEvent_signalLpEventFast(viopath_hostLp
,
228 HvLpEvent_Type_VirtualIo
,
229 viomajorsubtype_cdio
| viocdclose
,
230 HvLpEvent_AckInd_NoAck
, HvLpEvent_AckType_ImmediateAck
,
231 viopath_sourceinst(viopath_hostLp
),
232 viopath_targetinst(viopath_hostLp
), 0,
233 VIOVERSION
<< 16, ((u64
)device_no
<< 48), 0, 0, 0);
235 printk(VIOCD_KERN_WARNING
236 "bad rc on HvCallEvent_signalLpEventFast %d\n",
240 /* Send a read or write request to OS/400 */
241 static int send_request(struct request
*req
)
244 struct disk_info
*diskinfo
= req
->rq_disk
->private_data
;
249 struct scatterlist sg
;
251 BUG_ON(req
->nr_phys_segments
> 1);
253 if (rq_data_dir(req
) == READ
) {
254 direction
= DMA_FROM_DEVICE
;
255 cmd
= viomajorsubtype_cdio
| viocdread
;
257 direction
= DMA_TO_DEVICE
;
258 cmd
= viomajorsubtype_cdio
| viocdwrite
;
261 sg_init_table(&sg
, 1);
262 if (blk_rq_map_sg(req
->q
, req
, &sg
) == 0) {
263 printk(VIOCD_KERN_WARNING
264 "error setting up scatter/gather list\n");
268 if (dma_map_sg(diskinfo
->dev
, &sg
, 1, direction
) == 0) {
269 printk(VIOCD_KERN_WARNING
"error allocating sg tce\n");
272 dmaaddr
= sg_dma_address(&sg
);
273 len
= sg_dma_len(&sg
);
275 hvrc
= HvCallEvent_signalLpEventFast(viopath_hostLp
,
276 HvLpEvent_Type_VirtualIo
, cmd
,
277 HvLpEvent_AckInd_DoAck
,
278 HvLpEvent_AckType_ImmediateAck
,
279 viopath_sourceinst(viopath_hostLp
),
280 viopath_targetinst(viopath_hostLp
),
281 (u64
)req
, VIOVERSION
<< 16,
282 ((u64
)DEVICE_NR(diskinfo
) << 48) | dmaaddr
,
283 (u64
)req
->sector
* 512, len
, 0);
284 if (hvrc
!= HvLpEvent_Rc_Good
) {
285 printk(VIOCD_KERN_WARNING
"hv error on op %d\n", (int)hvrc
);
292 static void viocd_end_request(struct request
*req
, int uptodate
)
294 int nsectors
= req
->hard_nr_sectors
;
297 * Make sure it's fully ended, and ensure that we process
298 * at least one sector.
300 if (blk_pc_request(req
))
301 nsectors
= (req
->data_len
+ 511) >> 9;
305 if (end_that_request_first(req
, uptodate
, nsectors
))
307 add_disk_randomness(req
->rq_disk
);
308 blkdev_dequeue_request(req
);
309 end_that_request_last(req
, uptodate
);
314 static void do_viocd_request(struct request_queue
*q
)
318 while ((rwreq
== 0) && ((req
= elv_next_request(q
)) != NULL
)) {
319 if (!blk_fs_request(req
))
320 viocd_end_request(req
, 0);
321 else if (send_request(req
) < 0) {
322 printk(VIOCD_KERN_WARNING
323 "unable to send message to OS/400!");
324 viocd_end_request(req
, 0);
330 static int viocd_media_changed(struct cdrom_device_info
*cdi
, int disc_nr
)
332 struct viocd_waitevent we
;
334 int device_no
= DEVICE_NR((struct disk_info
*)cdi
->handle
);
336 init_completion(&we
.com
);
338 /* Send the open event to OS/400 */
339 hvrc
= HvCallEvent_signalLpEventFast(viopath_hostLp
,
340 HvLpEvent_Type_VirtualIo
,
341 viomajorsubtype_cdio
| viocdcheck
,
342 HvLpEvent_AckInd_DoAck
, HvLpEvent_AckType_ImmediateAck
,
343 viopath_sourceinst(viopath_hostLp
),
344 viopath_targetinst(viopath_hostLp
),
345 (u64
)&we
, VIOVERSION
<< 16, ((u64
)device_no
<< 48),
348 printk(VIOCD_KERN_WARNING
"bad rc on HvCallEvent_signalLpEventFast %d\n",
353 wait_for_completion(&we
.com
);
355 /* Check the return code. If bad, assume no change */
357 const struct vio_error_entry
*err
=
358 vio_lookup_rc(viocd_err_table
, we
.sub_result
);
359 printk(VIOCD_KERN_WARNING
360 "bad rc %d:0x%04X on check_change: %s; Assuming no change\n",
361 we
.rc
, we
.sub_result
, err
->msg
);
368 static int viocd_lock_door(struct cdrom_device_info
*cdi
, int locking
)
371 u64 device_no
= DEVICE_NR((struct disk_info
*)cdi
->handle
);
372 /* NOTE: flags is 1 or 0 so it won't overwrite the device_no */
373 u64 flags
= !!locking
;
374 struct viocd_waitevent we
;
376 init_completion(&we
.com
);
378 /* Send the lockdoor event to OS/400 */
379 hvrc
= HvCallEvent_signalLpEventFast(viopath_hostLp
,
380 HvLpEvent_Type_VirtualIo
,
381 viomajorsubtype_cdio
| viocdlockdoor
,
382 HvLpEvent_AckInd_DoAck
, HvLpEvent_AckType_ImmediateAck
,
383 viopath_sourceinst(viopath_hostLp
),
384 viopath_targetinst(viopath_hostLp
),
385 (u64
)&we
, VIOVERSION
<< 16,
386 (device_no
<< 48) | (flags
<< 32), 0, 0, 0);
388 printk(VIOCD_KERN_WARNING
"bad rc on HvCallEvent_signalLpEventFast %d\n",
393 wait_for_completion(&we
.com
);
400 static int viocd_packet(struct cdrom_device_info
*cdi
,
401 struct packet_command
*cgc
)
403 unsigned int buflen
= cgc
->buflen
;
406 switch (cgc
->cmd
[0]) {
407 case GPCMD_READ_DISC_INFO
:
409 disc_information
*di
= (disc_information
*)cgc
->buffer
;
412 di
->disc_information_length
= cpu_to_be16(1);
417 (cdi
->ops
->capability
& ~cdi
->mask
418 & (CDC_DVD_RAM
| CDC_RAM
)) != 0;
421 case GPCMD_GET_CONFIGURATION
:
422 if (cgc
->cmd
[3] == CDF_RWRT
) {
423 struct rwrt_feature_desc
*rfd
= (struct rwrt_feature_desc
*)(cgc
->buffer
+ sizeof(struct feature_header
));
426 (sizeof(struct feature_header
) + sizeof(*rfd
))) &&
427 (cdi
->ops
->capability
& ~cdi
->mask
428 & (CDC_DVD_RAM
| CDC_RAM
))) {
429 rfd
->feature_code
= cpu_to_be16(CDF_RWRT
);
437 /* indicate Unknown code */
438 cgc
->sense
->sense_key
= 0x05;
439 cgc
->sense
->asc
= 0x20;
440 cgc
->sense
->ascq
= 0x00;
449 static void restart_all_queues(int first_index
)
453 for (i
= first_index
+ 1; i
< viocd_numdev
; i
++)
454 if (viocd_diskinfo
[i
].viocd_disk
)
455 blk_run_queue(viocd_diskinfo
[i
].viocd_disk
->queue
);
456 for (i
= 0; i
<= first_index
; i
++)
457 if (viocd_diskinfo
[i
].viocd_disk
)
458 blk_run_queue(viocd_diskinfo
[i
].viocd_disk
->queue
);
461 /* This routine handles incoming CD LP events */
462 static void vio_handle_cd_event(struct HvLpEvent
*event
)
464 struct viocdlpevent
*bevent
;
465 struct viocd_waitevent
*pwe
;
466 struct disk_info
*di
;
472 /* Notification that a partition went away! */
474 /* First, we should NEVER get an int here...only acks */
475 if (hvlpevent_is_int(event
)) {
476 printk(VIOCD_KERN_WARNING
477 "Yikes! got an int in viocd event handler!\n");
478 if (hvlpevent_need_ack(event
)) {
479 event
->xRc
= HvLpEvent_Rc_InvalidSubtype
;
480 HvCallEvent_ackLpEvent(event
);
484 bevent
= (struct viocdlpevent
*)event
;
486 switch (event
->xSubtype
& VIOMINOR_SUBTYPE_MASK
) {
488 if (event
->xRc
== 0) {
489 di
= &viocd_diskinfo
[bevent
->disk
];
490 blk_queue_hardsect_size(di
->viocd_disk
->queue
,
492 set_capacity(di
->viocd_disk
,
494 bevent
->block_size
/ 512);
498 pwe
= (struct viocd_waitevent
*)event
->xCorrelationToken
;
500 pwe
->rc
= event
->xRc
;
501 pwe
->sub_result
= bevent
->sub_result
;
506 pwe
= (struct viocd_waitevent
*)event
->xCorrelationToken
;
507 pwe
->changed
= bevent
->flags
;
508 goto return_complete
;
516 * Since this is running in interrupt mode, we need to
517 * make sure we're not stepping on any global I/O operations
519 di
= &viocd_diskinfo
[bevent
->disk
];
520 spin_lock_irqsave(&viocd_reqlock
, flags
);
521 dma_unmap_single(di
->dev
, bevent
->token
, bevent
->len
,
522 ((event
->xSubtype
& VIOMINOR_SUBTYPE_MASK
) == viocdread
)
523 ? DMA_FROM_DEVICE
: DMA_TO_DEVICE
);
524 req
= (struct request
*)bevent
->event
.xCorrelationToken
;
527 if (event
->xRc
!= HvLpEvent_Rc_Good
) {
528 const struct vio_error_entry
*err
=
529 vio_lookup_rc(viocd_err_table
,
531 printk(VIOCD_KERN_WARNING
"request %p failed "
532 "with rc %d:0x%04X: %s\n",
534 bevent
->sub_result
, err
->msg
);
535 viocd_end_request(req
, 0);
537 viocd_end_request(req
, 1);
539 /* restart handling of incoming requests */
540 spin_unlock_irqrestore(&viocd_reqlock
, flags
);
541 restart_all_queues(bevent
->disk
);
545 printk(VIOCD_KERN_WARNING
546 "message with invalid subtype %0x04X!\n",
547 event
->xSubtype
& VIOMINOR_SUBTYPE_MASK
);
548 if (hvlpevent_need_ack(event
)) {
549 event
->xRc
= HvLpEvent_Rc_InvalidSubtype
;
550 HvCallEvent_ackLpEvent(event
);
555 static struct cdrom_device_ops viocd_dops
= {
557 .release
= viocd_release
,
558 .media_changed
= viocd_media_changed
,
559 .lock_door
= viocd_lock_door
,
560 .generic_packet
= viocd_packet
,
561 .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
564 static int __init
find_capability(const char *type
)
566 struct capability_entry
*entry
;
568 for(entry
= capability_table
; entry
->type
; ++entry
)
569 if(!strncmp(entry
->type
, type
, 4))
571 return entry
->capability
;
574 static int viocd_probe(struct vio_dev
*vdev
, const struct vio_device_id
*id
)
576 struct gendisk
*gendisk
;
579 struct cdrom_device_info
*c
;
580 struct request_queue
*q
;
581 struct device_node
*node
= vdev
->dev
.archdata
.of_node
;
583 deviceno
= vdev
->unit_address
;
584 if (deviceno
> VIOCD_MAX_CD
)
589 if (deviceno
>= viocd_numdev
)
590 viocd_numdev
= deviceno
+ 1;
592 d
= &viocd_diskinfo
[deviceno
];
593 d
->rsrcname
= of_get_property(node
, "linux,vio_rsrcname", NULL
);
594 d
->type
= of_get_property(node
, "linux,vio_type", NULL
);
595 d
->model
= of_get_property(node
, "linux,vio_model", NULL
);
599 c
->ops
= &viocd_dops
;
603 c
->mask
= ~find_capability(d
->type
);
604 sprintf(c
->name
, VIOCD_DEVICE
"%c", 'a' + deviceno
);
606 if (register_cdrom(c
) != 0) {
607 printk(VIOCD_KERN_WARNING
"Cannot register viocd CD-ROM %s!\n",
611 printk(VIOCD_KERN_INFO
"cd %s is iSeries resource %10.10s "
612 "type %4.4s, model %3.3s\n",
613 c
->name
, d
->rsrcname
, d
->type
, d
->model
);
614 q
= blk_init_queue(do_viocd_request
, &viocd_reqlock
);
616 printk(VIOCD_KERN_WARNING
"Cannot allocate queue for %s!\n",
618 goto out_unregister_cdrom
;
620 gendisk
= alloc_disk(1);
621 if (gendisk
== NULL
) {
622 printk(VIOCD_KERN_WARNING
"Cannot create gendisk for %s!\n",
624 goto out_cleanup_queue
;
626 gendisk
->major
= VIOCD_MAJOR
;
627 gendisk
->first_minor
= deviceno
;
628 strncpy(gendisk
->disk_name
, c
->name
,
629 sizeof(gendisk
->disk_name
));
630 blk_queue_max_hw_segments(q
, 1);
631 blk_queue_max_phys_segments(q
, 1);
632 blk_queue_max_sectors(q
, 4096 / 512);
634 gendisk
->fops
= &viocd_fops
;
635 gendisk
->flags
= GENHD_FL_CD
|GENHD_FL_REMOVABLE
;
636 set_capacity(gendisk
, 0);
637 gendisk
->private_data
= d
;
638 d
->viocd_disk
= gendisk
;
640 gendisk
->driverfs_dev
= d
->dev
;
645 blk_cleanup_queue(q
);
646 out_unregister_cdrom
:
652 static int viocd_remove(struct vio_dev
*vdev
)
654 struct disk_info
*d
= &viocd_diskinfo
[vdev
->unit_address
];
656 if (unregister_cdrom(&d
->viocd_info
) != 0)
657 printk(VIOCD_KERN_WARNING
658 "Cannot unregister viocd CD-ROM %s!\n",
660 del_gendisk(d
->viocd_disk
);
661 blk_cleanup_queue(d
->viocd_disk
->queue
);
662 put_disk(d
->viocd_disk
);
667 * viocd_device_table: Used by vio.c to match devices that we
670 static struct vio_device_id viocd_device_table
[] __devinitdata
= {
671 { "block", "IBM,iSeries-viocd" },
674 MODULE_DEVICE_TABLE(vio
, viocd_device_table
);
676 static struct vio_driver viocd_driver
= {
677 .id_table
= viocd_device_table
,
678 .probe
= viocd_probe
,
679 .remove
= viocd_remove
,
682 .owner
= THIS_MODULE
,
686 static int __init
viocd_init(void)
688 struct proc_dir_entry
*e
;
691 if (!firmware_has_feature(FW_FEATURE_ISERIES
))
694 if (viopath_hostLp
== HvLpIndexInvalid
) {
696 /* If we don't have a host, bail out */
697 if (viopath_hostLp
== HvLpIndexInvalid
)
701 printk(VIOCD_KERN_INFO
"vers " VIOCD_VERS
", hosting partition %d\n",
704 if (register_blkdev(VIOCD_MAJOR
, VIOCD_DEVICE
) != 0) {
705 printk(VIOCD_KERN_WARNING
"Unable to get major %d for %s\n",
706 VIOCD_MAJOR
, VIOCD_DEVICE
);
710 ret
= viopath_open(viopath_hostLp
, viomajorsubtype_cdio
,
713 printk(VIOCD_KERN_WARNING
714 "error opening path to host partition %d\n",
719 /* Initialize our request handler */
720 vio_setHandler(viomajorsubtype_cdio
, vio_handle_cd_event
);
722 spin_lock_init(&viocd_reqlock
);
724 ret
= vio_register_driver(&viocd_driver
);
728 e
= create_proc_entry("iSeries/viocd", S_IFREG
|S_IRUGO
, NULL
);
730 e
->owner
= THIS_MODULE
;
731 e
->proc_fops
= &proc_viocd_operations
;
737 vio_clearHandler(viomajorsubtype_cdio
);
738 viopath_close(viopath_hostLp
, viomajorsubtype_cdio
, MAX_CD_REQ
+ 2);
740 unregister_blkdev(VIOCD_MAJOR
, VIOCD_DEVICE
);
744 static void __exit
viocd_exit(void)
746 remove_proc_entry("iSeries/viocd", NULL
);
747 vio_unregister_driver(&viocd_driver
);
748 viopath_close(viopath_hostLp
, viomajorsubtype_cdio
, MAX_CD_REQ
+ 2);
749 vio_clearHandler(viomajorsubtype_cdio
);
750 unregister_blkdev(VIOCD_MAJOR
, VIOCD_DEVICE
);
753 module_init(viocd_init
);
754 module_exit(viocd_exit
);
755 MODULE_LICENSE("GPL");