2 * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
3 * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
4 * Copyright (C) 2006 Thomas Maier <balagi@justmail.de>
6 * May be copied or modified under the terms of the GNU General Public
7 * License. See linux/COPYING for more information.
9 * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
12 * Theory of operation:
14 * At the lowest level, there is the standard driver for the CD/DVD device,
15 * typically ide-cd.c or sr.c. This driver can handle read and write requests,
16 * but it doesn't know anything about the special restrictions that apply to
17 * packet writing. One restriction is that write requests must be aligned to
18 * packet boundaries on the physical media, and the size of a write request
19 * must be equal to the packet size. Another restriction is that a
20 * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
21 * command, if the previous command was a write.
23 * The purpose of the packet writing driver is to hide these restrictions from
24 * higher layers, such as file systems, and present a block device that can be
25 * randomly read and written using 2kB-sized blocks.
27 * The lowest layer in the packet writing driver is the packet I/O scheduler.
28 * Its data is defined by the struct packet_iosched and includes two bio
29 * queues with pending read and write requests. These queues are processed
30 * by the pkt_iosched_process_queue() function. The write requests in this
31 * queue are already properly aligned and sized. This layer is responsible for
32 * issuing the flush cache commands and scheduling the I/O in a good order.
34 * The next layer transforms unaligned write requests to aligned writes. This
35 * transformation requires reading missing pieces of data from the underlying
36 * block device, assembling the pieces to full packets and queuing them to the
37 * packet I/O scheduler.
39 * At the top layer there is a custom make_request_fn function that forwards
40 * read requests directly to the iosched queue and puts write requests in the
41 * unaligned write queue. A kernel thread performs the necessary read
42 * gathering to convert the unaligned writes to aligned writes and then feeds
43 * them to the packet I/O scheduler.
45 *************************************************************************/
47 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
49 #include <linux/pktcdvd.h>
50 #include <linux/module.h>
51 #include <linux/types.h>
52 #include <linux/kernel.h>
53 #include <linux/compat.h>
54 #include <linux/kthread.h>
55 #include <linux/errno.h>
56 #include <linux/spinlock.h>
57 #include <linux/file.h>
58 #include <linux/proc_fs.h>
59 #include <linux/seq_file.h>
60 #include <linux/miscdevice.h>
61 #include <linux/freezer.h>
62 #include <linux/mutex.h>
63 #include <linux/slab.h>
64 #include <linux/backing-dev.h>
65 #include <scsi/scsi_cmnd.h>
66 #include <scsi/scsi_ioctl.h>
67 #include <scsi/scsi.h>
68 #include <linux/debugfs.h>
69 #include <linux/device.h>
71 #include <asm/uaccess.h>
73 #define DRIVER_NAME "pktcdvd"
75 #define pkt_err(pd, fmt, ...) \
76 pr_err("%s: " fmt, pd->name, ##__VA_ARGS__)
77 #define pkt_notice(pd, fmt, ...) \
78 pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__)
79 #define pkt_info(pd, fmt, ...) \
80 pr_info("%s: " fmt, pd->name, ##__VA_ARGS__)
82 #define pkt_dbg(level, pd, fmt, ...) \
84 if (level == 2 && PACKET_DEBUG >= 2) \
85 pr_notice("%s: %s():" fmt, \
86 pd->name, __func__, ##__VA_ARGS__); \
87 else if (level == 1 && PACKET_DEBUG >= 1) \
88 pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__); \
91 #define MAX_SPEED 0xffff
93 static DEFINE_MUTEX(pktcdvd_mutex
);
94 static struct pktcdvd_device
*pkt_devs
[MAX_WRITERS
];
95 static struct proc_dir_entry
*pkt_proc
;
96 static int pktdev_major
;
97 static int write_congestion_on
= PKT_WRITE_CONGESTION_ON
;
98 static int write_congestion_off
= PKT_WRITE_CONGESTION_OFF
;
99 static struct mutex ctl_mutex
; /* Serialize open/close/setup/teardown */
100 static mempool_t
*psd_pool
;
102 static struct class *class_pktcdvd
= NULL
; /* /sys/class/pktcdvd */
103 static struct dentry
*pkt_debugfs_root
= NULL
; /* /sys/kernel/debug/pktcdvd */
105 /* forward declaration */
106 static int pkt_setup_dev(dev_t dev
, dev_t
* pkt_dev
);
107 static int pkt_remove_dev(dev_t pkt_dev
);
108 static int pkt_seq_show(struct seq_file
*m
, void *p
);
110 static sector_t
get_zone(sector_t sector
, struct pktcdvd_device
*pd
)
112 return (sector
+ pd
->offset
) & ~(sector_t
)(pd
->settings
.size
- 1);
116 * create and register a pktcdvd kernel object.
118 static struct pktcdvd_kobj
* pkt_kobj_create(struct pktcdvd_device
*pd
,
120 struct kobject
* parent
,
121 struct kobj_type
* ktype
)
123 struct pktcdvd_kobj
*p
;
126 p
= kzalloc(sizeof(*p
), GFP_KERNEL
);
130 error
= kobject_init_and_add(&p
->kobj
, ktype
, parent
, "%s", name
);
132 kobject_put(&p
->kobj
);
135 kobject_uevent(&p
->kobj
, KOBJ_ADD
);
139 * remove a pktcdvd kernel object.
141 static void pkt_kobj_remove(struct pktcdvd_kobj
*p
)
144 kobject_put(&p
->kobj
);
147 * default release function for pktcdvd kernel objects.
149 static void pkt_kobj_release(struct kobject
*kobj
)
151 kfree(to_pktcdvdkobj(kobj
));
155 /**********************************************************
157 * sysfs interface for pktcdvd
158 * by (C) 2006 Thomas Maier <balagi@justmail.de>
160 **********************************************************/
162 #define DEF_ATTR(_obj,_name,_mode) \
163 static struct attribute _obj = { .name = _name, .mode = _mode }
165 /**********************************************************
166 /sys/class/pktcdvd/pktcdvd[0-7]/
169 stat/packets_finished
174 write_queue/congestion_off
175 write_queue/congestion_on
176 **********************************************************/
178 DEF_ATTR(kobj_pkt_attr_st1
, "reset", 0200);
179 DEF_ATTR(kobj_pkt_attr_st2
, "packets_started", 0444);
180 DEF_ATTR(kobj_pkt_attr_st3
, "packets_finished", 0444);
181 DEF_ATTR(kobj_pkt_attr_st4
, "kb_written", 0444);
182 DEF_ATTR(kobj_pkt_attr_st5
, "kb_read", 0444);
183 DEF_ATTR(kobj_pkt_attr_st6
, "kb_read_gather", 0444);
185 static struct attribute
*kobj_pkt_attrs_stat
[] = {
195 DEF_ATTR(kobj_pkt_attr_wq1
, "size", 0444);
196 DEF_ATTR(kobj_pkt_attr_wq2
, "congestion_off", 0644);
197 DEF_ATTR(kobj_pkt_attr_wq3
, "congestion_on", 0644);
199 static struct attribute
*kobj_pkt_attrs_wqueue
[] = {
206 static ssize_t
kobj_pkt_show(struct kobject
*kobj
,
207 struct attribute
*attr
, char *data
)
209 struct pktcdvd_device
*pd
= to_pktcdvdkobj(kobj
)->pd
;
212 if (strcmp(attr
->name
, "packets_started") == 0) {
213 n
= sprintf(data
, "%lu\n", pd
->stats
.pkt_started
);
215 } else if (strcmp(attr
->name
, "packets_finished") == 0) {
216 n
= sprintf(data
, "%lu\n", pd
->stats
.pkt_ended
);
218 } else if (strcmp(attr
->name
, "kb_written") == 0) {
219 n
= sprintf(data
, "%lu\n", pd
->stats
.secs_w
>> 1);
221 } else if (strcmp(attr
->name
, "kb_read") == 0) {
222 n
= sprintf(data
, "%lu\n", pd
->stats
.secs_r
>> 1);
224 } else if (strcmp(attr
->name
, "kb_read_gather") == 0) {
225 n
= sprintf(data
, "%lu\n", pd
->stats
.secs_rg
>> 1);
227 } else if (strcmp(attr
->name
, "size") == 0) {
228 spin_lock(&pd
->lock
);
229 v
= pd
->bio_queue_size
;
230 spin_unlock(&pd
->lock
);
231 n
= sprintf(data
, "%d\n", v
);
233 } else if (strcmp(attr
->name
, "congestion_off") == 0) {
234 spin_lock(&pd
->lock
);
235 v
= pd
->write_congestion_off
;
236 spin_unlock(&pd
->lock
);
237 n
= sprintf(data
, "%d\n", v
);
239 } else if (strcmp(attr
->name
, "congestion_on") == 0) {
240 spin_lock(&pd
->lock
);
241 v
= pd
->write_congestion_on
;
242 spin_unlock(&pd
->lock
);
243 n
= sprintf(data
, "%d\n", v
);
248 static void init_write_congestion_marks(int* lo
, int* hi
)
252 *hi
= min(*hi
, 1000000);
256 *lo
= min(*lo
, *hi
- 100);
265 static ssize_t
kobj_pkt_store(struct kobject
*kobj
,
266 struct attribute
*attr
,
267 const char *data
, size_t len
)
269 struct pktcdvd_device
*pd
= to_pktcdvdkobj(kobj
)->pd
;
272 if (strcmp(attr
->name
, "reset") == 0 && len
> 0) {
273 pd
->stats
.pkt_started
= 0;
274 pd
->stats
.pkt_ended
= 0;
275 pd
->stats
.secs_w
= 0;
276 pd
->stats
.secs_rg
= 0;
277 pd
->stats
.secs_r
= 0;
279 } else if (strcmp(attr
->name
, "congestion_off") == 0
280 && sscanf(data
, "%d", &val
) == 1) {
281 spin_lock(&pd
->lock
);
282 pd
->write_congestion_off
= val
;
283 init_write_congestion_marks(&pd
->write_congestion_off
,
284 &pd
->write_congestion_on
);
285 spin_unlock(&pd
->lock
);
287 } else if (strcmp(attr
->name
, "congestion_on") == 0
288 && sscanf(data
, "%d", &val
) == 1) {
289 spin_lock(&pd
->lock
);
290 pd
->write_congestion_on
= val
;
291 init_write_congestion_marks(&pd
->write_congestion_off
,
292 &pd
->write_congestion_on
);
293 spin_unlock(&pd
->lock
);
298 static const struct sysfs_ops kobj_pkt_ops
= {
299 .show
= kobj_pkt_show
,
300 .store
= kobj_pkt_store
302 static struct kobj_type kobj_pkt_type_stat
= {
303 .release
= pkt_kobj_release
,
304 .sysfs_ops
= &kobj_pkt_ops
,
305 .default_attrs
= kobj_pkt_attrs_stat
307 static struct kobj_type kobj_pkt_type_wqueue
= {
308 .release
= pkt_kobj_release
,
309 .sysfs_ops
= &kobj_pkt_ops
,
310 .default_attrs
= kobj_pkt_attrs_wqueue
313 static void pkt_sysfs_dev_new(struct pktcdvd_device
*pd
)
316 pd
->dev
= device_create(class_pktcdvd
, NULL
, MKDEV(0, 0), NULL
,
322 pd
->kobj_stat
= pkt_kobj_create(pd
, "stat",
324 &kobj_pkt_type_stat
);
325 pd
->kobj_wqueue
= pkt_kobj_create(pd
, "write_queue",
327 &kobj_pkt_type_wqueue
);
331 static void pkt_sysfs_dev_remove(struct pktcdvd_device
*pd
)
333 pkt_kobj_remove(pd
->kobj_stat
);
334 pkt_kobj_remove(pd
->kobj_wqueue
);
336 device_unregister(pd
->dev
);
340 /********************************************************************
343 remove unmap packet dev
344 device_map show mappings
345 *******************************************************************/
347 static void class_pktcdvd_release(struct class *cls
)
351 static ssize_t
class_pktcdvd_show_map(struct class *c
,
352 struct class_attribute
*attr
,
357 mutex_lock_nested(&ctl_mutex
, SINGLE_DEPTH_NESTING
);
358 for (idx
= 0; idx
< MAX_WRITERS
; idx
++) {
359 struct pktcdvd_device
*pd
= pkt_devs
[idx
];
362 n
+= sprintf(data
+n
, "%s %u:%u %u:%u\n",
364 MAJOR(pd
->pkt_dev
), MINOR(pd
->pkt_dev
),
365 MAJOR(pd
->bdev
->bd_dev
),
366 MINOR(pd
->bdev
->bd_dev
));
368 mutex_unlock(&ctl_mutex
);
372 static ssize_t
class_pktcdvd_store_add(struct class *c
,
373 struct class_attribute
*attr
,
377 unsigned int major
, minor
;
379 if (sscanf(buf
, "%u:%u", &major
, &minor
) == 2) {
380 /* pkt_setup_dev() expects caller to hold reference to self */
381 if (!try_module_get(THIS_MODULE
))
384 pkt_setup_dev(MKDEV(major
, minor
), NULL
);
386 module_put(THIS_MODULE
);
394 static ssize_t
class_pktcdvd_store_remove(struct class *c
,
395 struct class_attribute
*attr
,
399 unsigned int major
, minor
;
400 if (sscanf(buf
, "%u:%u", &major
, &minor
) == 2) {
401 pkt_remove_dev(MKDEV(major
, minor
));
407 static struct class_attribute class_pktcdvd_attrs
[] = {
408 __ATTR(add
, 0200, NULL
, class_pktcdvd_store_add
),
409 __ATTR(remove
, 0200, NULL
, class_pktcdvd_store_remove
),
410 __ATTR(device_map
, 0444, class_pktcdvd_show_map
, NULL
),
415 static int pkt_sysfs_init(void)
420 * create control files in sysfs
421 * /sys/class/pktcdvd/...
423 class_pktcdvd
= kzalloc(sizeof(*class_pktcdvd
), GFP_KERNEL
);
426 class_pktcdvd
->name
= DRIVER_NAME
;
427 class_pktcdvd
->owner
= THIS_MODULE
;
428 class_pktcdvd
->class_release
= class_pktcdvd_release
;
429 class_pktcdvd
->class_attrs
= class_pktcdvd_attrs
;
430 ret
= class_register(class_pktcdvd
);
432 kfree(class_pktcdvd
);
433 class_pktcdvd
= NULL
;
434 pr_err("failed to create class pktcdvd\n");
440 static void pkt_sysfs_cleanup(void)
443 class_destroy(class_pktcdvd
);
444 class_pktcdvd
= NULL
;
447 /********************************************************************
450 /sys/kernel/debug/pktcdvd[0-7]/
453 *******************************************************************/
455 static int pkt_debugfs_seq_show(struct seq_file
*m
, void *p
)
457 return pkt_seq_show(m
, p
);
460 static int pkt_debugfs_fops_open(struct inode
*inode
, struct file
*file
)
462 return single_open(file
, pkt_debugfs_seq_show
, inode
->i_private
);
465 static const struct file_operations debug_fops
= {
466 .open
= pkt_debugfs_fops_open
,
469 .release
= single_release
,
470 .owner
= THIS_MODULE
,
473 static void pkt_debugfs_dev_new(struct pktcdvd_device
*pd
)
475 if (!pkt_debugfs_root
)
477 pd
->dfs_d_root
= debugfs_create_dir(pd
->name
, pkt_debugfs_root
);
481 pd
->dfs_f_info
= debugfs_create_file("info", S_IRUGO
,
482 pd
->dfs_d_root
, pd
, &debug_fops
);
485 static void pkt_debugfs_dev_remove(struct pktcdvd_device
*pd
)
487 if (!pkt_debugfs_root
)
489 debugfs_remove(pd
->dfs_f_info
);
490 debugfs_remove(pd
->dfs_d_root
);
491 pd
->dfs_f_info
= NULL
;
492 pd
->dfs_d_root
= NULL
;
495 static void pkt_debugfs_init(void)
497 pkt_debugfs_root
= debugfs_create_dir(DRIVER_NAME
, NULL
);
500 static void pkt_debugfs_cleanup(void)
502 debugfs_remove(pkt_debugfs_root
);
503 pkt_debugfs_root
= NULL
;
506 /* ----------------------------------------------------------*/
509 static void pkt_bio_finished(struct pktcdvd_device
*pd
)
511 BUG_ON(atomic_read(&pd
->cdrw
.pending_bios
) <= 0);
512 if (atomic_dec_and_test(&pd
->cdrw
.pending_bios
)) {
513 pkt_dbg(2, pd
, "queue empty\n");
514 atomic_set(&pd
->iosched
.attention
, 1);
515 wake_up(&pd
->wqueue
);
520 * Allocate a packet_data struct
522 static struct packet_data
*pkt_alloc_packet_data(int frames
)
525 struct packet_data
*pkt
;
527 pkt
= kzalloc(sizeof(struct packet_data
), GFP_KERNEL
);
531 pkt
->frames
= frames
;
532 pkt
->w_bio
= bio_kmalloc(GFP_KERNEL
, frames
);
536 for (i
= 0; i
< frames
/ FRAMES_PER_PAGE
; i
++) {
537 pkt
->pages
[i
] = alloc_page(GFP_KERNEL
|__GFP_ZERO
);
542 spin_lock_init(&pkt
->lock
);
543 bio_list_init(&pkt
->orig_bios
);
545 for (i
= 0; i
< frames
; i
++) {
546 struct bio
*bio
= bio_kmalloc(GFP_KERNEL
, 1);
550 pkt
->r_bios
[i
] = bio
;
556 for (i
= 0; i
< frames
; i
++) {
557 struct bio
*bio
= pkt
->r_bios
[i
];
563 for (i
= 0; i
< frames
/ FRAMES_PER_PAGE
; i
++)
565 __free_page(pkt
->pages
[i
]);
574 * Free a packet_data struct
576 static void pkt_free_packet_data(struct packet_data
*pkt
)
580 for (i
= 0; i
< pkt
->frames
; i
++) {
581 struct bio
*bio
= pkt
->r_bios
[i
];
585 for (i
= 0; i
< pkt
->frames
/ FRAMES_PER_PAGE
; i
++)
586 __free_page(pkt
->pages
[i
]);
591 static void pkt_shrink_pktlist(struct pktcdvd_device
*pd
)
593 struct packet_data
*pkt
, *next
;
595 BUG_ON(!list_empty(&pd
->cdrw
.pkt_active_list
));
597 list_for_each_entry_safe(pkt
, next
, &pd
->cdrw
.pkt_free_list
, list
) {
598 pkt_free_packet_data(pkt
);
600 INIT_LIST_HEAD(&pd
->cdrw
.pkt_free_list
);
603 static int pkt_grow_pktlist(struct pktcdvd_device
*pd
, int nr_packets
)
605 struct packet_data
*pkt
;
607 BUG_ON(!list_empty(&pd
->cdrw
.pkt_free_list
));
609 while (nr_packets
> 0) {
610 pkt
= pkt_alloc_packet_data(pd
->settings
.size
>> 2);
612 pkt_shrink_pktlist(pd
);
615 pkt
->id
= nr_packets
;
617 list_add(&pkt
->list
, &pd
->cdrw
.pkt_free_list
);
623 static inline struct pkt_rb_node
*pkt_rbtree_next(struct pkt_rb_node
*node
)
625 struct rb_node
*n
= rb_next(&node
->rb_node
);
628 return rb_entry(n
, struct pkt_rb_node
, rb_node
);
631 static void pkt_rbtree_erase(struct pktcdvd_device
*pd
, struct pkt_rb_node
*node
)
633 rb_erase(&node
->rb_node
, &pd
->bio_queue
);
634 mempool_free(node
, pd
->rb_pool
);
635 pd
->bio_queue_size
--;
636 BUG_ON(pd
->bio_queue_size
< 0);
640 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
642 static struct pkt_rb_node
*pkt_rbtree_find(struct pktcdvd_device
*pd
, sector_t s
)
644 struct rb_node
*n
= pd
->bio_queue
.rb_node
;
645 struct rb_node
*next
;
646 struct pkt_rb_node
*tmp
;
649 BUG_ON(pd
->bio_queue_size
> 0);
654 tmp
= rb_entry(n
, struct pkt_rb_node
, rb_node
);
655 if (s
<= tmp
->bio
->bi_iter
.bi_sector
)
664 if (s
> tmp
->bio
->bi_iter
.bi_sector
) {
665 tmp
= pkt_rbtree_next(tmp
);
669 BUG_ON(s
> tmp
->bio
->bi_iter
.bi_sector
);
674 * Insert a node into the pd->bio_queue rb tree.
676 static void pkt_rbtree_insert(struct pktcdvd_device
*pd
, struct pkt_rb_node
*node
)
678 struct rb_node
**p
= &pd
->bio_queue
.rb_node
;
679 struct rb_node
*parent
= NULL
;
680 sector_t s
= node
->bio
->bi_iter
.bi_sector
;
681 struct pkt_rb_node
*tmp
;
685 tmp
= rb_entry(parent
, struct pkt_rb_node
, rb_node
);
686 if (s
< tmp
->bio
->bi_iter
.bi_sector
)
691 rb_link_node(&node
->rb_node
, parent
, p
);
692 rb_insert_color(&node
->rb_node
, &pd
->bio_queue
);
693 pd
->bio_queue_size
++;
697 * Send a packet_command to the underlying block device and
698 * wait for completion.
700 static int pkt_generic_packet(struct pktcdvd_device
*pd
, struct packet_command
*cgc
)
702 struct request_queue
*q
= bdev_get_queue(pd
->bdev
);
706 rq
= blk_get_request(q
, (cgc
->data_direction
== CGC_DATA_WRITE
) ?
707 WRITE
: READ
, __GFP_WAIT
);
710 blk_rq_set_block_pc(rq
);
713 ret
= blk_rq_map_kern(q
, rq
, cgc
->buffer
, cgc
->buflen
,
719 rq
->cmd_len
= COMMAND_SIZE(cgc
->cmd
[0]);
720 memcpy(rq
->cmd
, cgc
->cmd
, CDROM_PACKET_SIZE
);
724 rq
->cmd_flags
|= REQ_QUIET
;
726 blk_execute_rq(rq
->q
, pd
->bdev
->bd_disk
, rq
, 0);
734 static const char *sense_key_string(__u8 index
)
736 static const char * const info
[] = {
737 "No sense", "Recovered error", "Not ready",
738 "Medium error", "Hardware error", "Illegal request",
739 "Unit attention", "Data protect", "Blank check",
742 return index
< ARRAY_SIZE(info
) ? info
[index
] : "INVALID";
746 * A generic sense dump / resolve mechanism should be implemented across
747 * all ATAPI + SCSI devices.
749 static void pkt_dump_sense(struct pktcdvd_device
*pd
,
750 struct packet_command
*cgc
)
752 struct request_sense
*sense
= cgc
->sense
;
755 pkt_err(pd
, "%*ph - sense %02x.%02x.%02x (%s)\n",
756 CDROM_PACKET_SIZE
, cgc
->cmd
,
757 sense
->sense_key
, sense
->asc
, sense
->ascq
,
758 sense_key_string(sense
->sense_key
));
760 pkt_err(pd
, "%*ph - no sense\n", CDROM_PACKET_SIZE
, cgc
->cmd
);
764 * flush the drive cache to media
766 static int pkt_flush_cache(struct pktcdvd_device
*pd
)
768 struct packet_command cgc
;
770 init_cdrom_command(&cgc
, NULL
, 0, CGC_DATA_NONE
);
771 cgc
.cmd
[0] = GPCMD_FLUSH_CACHE
;
775 * the IMMED bit -- we default to not setting it, although that
776 * would allow a much faster close, this is safer
781 return pkt_generic_packet(pd
, &cgc
);
785 * speed is given as the normal factor, e.g. 4 for 4x
787 static noinline_for_stack
int pkt_set_speed(struct pktcdvd_device
*pd
,
788 unsigned write_speed
, unsigned read_speed
)
790 struct packet_command cgc
;
791 struct request_sense sense
;
794 init_cdrom_command(&cgc
, NULL
, 0, CGC_DATA_NONE
);
796 cgc
.cmd
[0] = GPCMD_SET_SPEED
;
797 cgc
.cmd
[2] = (read_speed
>> 8) & 0xff;
798 cgc
.cmd
[3] = read_speed
& 0xff;
799 cgc
.cmd
[4] = (write_speed
>> 8) & 0xff;
800 cgc
.cmd
[5] = write_speed
& 0xff;
802 if ((ret
= pkt_generic_packet(pd
, &cgc
)))
803 pkt_dump_sense(pd
, &cgc
);
809 * Queue a bio for processing by the low-level CD device. Must be called
810 * from process context.
812 static void pkt_queue_bio(struct pktcdvd_device
*pd
, struct bio
*bio
)
814 spin_lock(&pd
->iosched
.lock
);
815 if (bio_data_dir(bio
) == READ
)
816 bio_list_add(&pd
->iosched
.read_queue
, bio
);
818 bio_list_add(&pd
->iosched
.write_queue
, bio
);
819 spin_unlock(&pd
->iosched
.lock
);
821 atomic_set(&pd
->iosched
.attention
, 1);
822 wake_up(&pd
->wqueue
);
826 * Process the queued read/write requests. This function handles special
827 * requirements for CDRW drives:
828 * - A cache flush command must be inserted before a read request if the
829 * previous request was a write.
830 * - Switching between reading and writing is slow, so don't do it more often
832 * - Optimize for throughput at the expense of latency. This means that streaming
833 * writes will never be interrupted by a read, but if the drive has to seek
834 * before the next write, switch to reading instead if there are any pending
836 * - Set the read speed according to current usage pattern. When only reading
837 * from the device, it's best to use the highest possible read speed, but
838 * when switching often between reading and writing, it's better to have the
839 * same read and write speeds.
841 static void pkt_iosched_process_queue(struct pktcdvd_device
*pd
)
844 if (atomic_read(&pd
->iosched
.attention
) == 0)
846 atomic_set(&pd
->iosched
.attention
, 0);
850 int reads_queued
, writes_queued
;
852 spin_lock(&pd
->iosched
.lock
);
853 reads_queued
= !bio_list_empty(&pd
->iosched
.read_queue
);
854 writes_queued
= !bio_list_empty(&pd
->iosched
.write_queue
);
855 spin_unlock(&pd
->iosched
.lock
);
857 if (!reads_queued
&& !writes_queued
)
860 if (pd
->iosched
.writing
) {
861 int need_write_seek
= 1;
862 spin_lock(&pd
->iosched
.lock
);
863 bio
= bio_list_peek(&pd
->iosched
.write_queue
);
864 spin_unlock(&pd
->iosched
.lock
);
865 if (bio
&& (bio
->bi_iter
.bi_sector
==
866 pd
->iosched
.last_write
))
868 if (need_write_seek
&& reads_queued
) {
869 if (atomic_read(&pd
->cdrw
.pending_bios
) > 0) {
870 pkt_dbg(2, pd
, "write, waiting\n");
874 pd
->iosched
.writing
= 0;
877 if (!reads_queued
&& writes_queued
) {
878 if (atomic_read(&pd
->cdrw
.pending_bios
) > 0) {
879 pkt_dbg(2, pd
, "read, waiting\n");
882 pd
->iosched
.writing
= 1;
886 spin_lock(&pd
->iosched
.lock
);
887 if (pd
->iosched
.writing
)
888 bio
= bio_list_pop(&pd
->iosched
.write_queue
);
890 bio
= bio_list_pop(&pd
->iosched
.read_queue
);
891 spin_unlock(&pd
->iosched
.lock
);
896 if (bio_data_dir(bio
) == READ
)
897 pd
->iosched
.successive_reads
+=
898 bio
->bi_iter
.bi_size
>> 10;
900 pd
->iosched
.successive_reads
= 0;
901 pd
->iosched
.last_write
= bio_end_sector(bio
);
903 if (pd
->iosched
.successive_reads
>= HI_SPEED_SWITCH
) {
904 if (pd
->read_speed
== pd
->write_speed
) {
905 pd
->read_speed
= MAX_SPEED
;
906 pkt_set_speed(pd
, pd
->write_speed
, pd
->read_speed
);
909 if (pd
->read_speed
!= pd
->write_speed
) {
910 pd
->read_speed
= pd
->write_speed
;
911 pkt_set_speed(pd
, pd
->write_speed
, pd
->read_speed
);
915 atomic_inc(&pd
->cdrw
.pending_bios
);
916 generic_make_request(bio
);
921 * Special care is needed if the underlying block device has a small
922 * max_phys_segments value.
924 static int pkt_set_segment_merging(struct pktcdvd_device
*pd
, struct request_queue
*q
)
926 if ((pd
->settings
.size
<< 9) / CD_FRAMESIZE
927 <= queue_max_segments(q
)) {
929 * The cdrom device can handle one segment/frame
931 clear_bit(PACKET_MERGE_SEGS
, &pd
->flags
);
933 } else if ((pd
->settings
.size
<< 9) / PAGE_SIZE
934 <= queue_max_segments(q
)) {
936 * We can handle this case at the expense of some extra memory
937 * copies during write operations
939 set_bit(PACKET_MERGE_SEGS
, &pd
->flags
);
942 pkt_err(pd
, "cdrom max_phys_segments too small\n");
948 * Copy all data for this packet to pkt->pages[], so that
949 * a) The number of required segments for the write bio is minimized, which
950 * is necessary for some scsi controllers.
951 * b) The data can be used as cache to avoid read requests if we receive a
952 * new write request for the same zone.
954 static void pkt_make_local_copy(struct packet_data
*pkt
, struct bio_vec
*bvec
)
958 /* Copy all data to pkt->pages[] */
961 for (f
= 0; f
< pkt
->frames
; f
++) {
962 if (bvec
[f
].bv_page
!= pkt
->pages
[p
]) {
963 void *vfrom
= kmap_atomic(bvec
[f
].bv_page
) + bvec
[f
].bv_offset
;
964 void *vto
= page_address(pkt
->pages
[p
]) + offs
;
965 memcpy(vto
, vfrom
, CD_FRAMESIZE
);
966 kunmap_atomic(vfrom
);
967 bvec
[f
].bv_page
= pkt
->pages
[p
];
968 bvec
[f
].bv_offset
= offs
;
970 BUG_ON(bvec
[f
].bv_offset
!= offs
);
972 offs
+= CD_FRAMESIZE
;
973 if (offs
>= PAGE_SIZE
) {
980 static void pkt_end_io_read(struct bio
*bio
, int err
)
982 struct packet_data
*pkt
= bio
->bi_private
;
983 struct pktcdvd_device
*pd
= pkt
->pd
;
986 pkt_dbg(2, pd
, "bio=%p sec0=%llx sec=%llx err=%d\n",
987 bio
, (unsigned long long)pkt
->sector
,
988 (unsigned long long)bio
->bi_iter
.bi_sector
, err
);
991 atomic_inc(&pkt
->io_errors
);
992 if (atomic_dec_and_test(&pkt
->io_wait
)) {
993 atomic_inc(&pkt
->run_sm
);
994 wake_up(&pd
->wqueue
);
996 pkt_bio_finished(pd
);
999 static void pkt_end_io_packet_write(struct bio
*bio
, int err
)
1001 struct packet_data
*pkt
= bio
->bi_private
;
1002 struct pktcdvd_device
*pd
= pkt
->pd
;
1005 pkt_dbg(2, pd
, "id=%d, err=%d\n", pkt
->id
, err
);
1007 pd
->stats
.pkt_ended
++;
1009 pkt_bio_finished(pd
);
1010 atomic_dec(&pkt
->io_wait
);
1011 atomic_inc(&pkt
->run_sm
);
1012 wake_up(&pd
->wqueue
);
1016 * Schedule reads for the holes in a packet
1018 static void pkt_gather_data(struct pktcdvd_device
*pd
, struct packet_data
*pkt
)
1020 int frames_read
= 0;
1023 char written
[PACKET_MAX_SIZE
];
1025 BUG_ON(bio_list_empty(&pkt
->orig_bios
));
1027 atomic_set(&pkt
->io_wait
, 0);
1028 atomic_set(&pkt
->io_errors
, 0);
1031 * Figure out which frames we need to read before we can write.
1033 memset(written
, 0, sizeof(written
));
1034 spin_lock(&pkt
->lock
);
1035 bio_list_for_each(bio
, &pkt
->orig_bios
) {
1036 int first_frame
= (bio
->bi_iter
.bi_sector
- pkt
->sector
) /
1037 (CD_FRAMESIZE
>> 9);
1038 int num_frames
= bio
->bi_iter
.bi_size
/ CD_FRAMESIZE
;
1039 pd
->stats
.secs_w
+= num_frames
* (CD_FRAMESIZE
>> 9);
1040 BUG_ON(first_frame
< 0);
1041 BUG_ON(first_frame
+ num_frames
> pkt
->frames
);
1042 for (f
= first_frame
; f
< first_frame
+ num_frames
; f
++)
1045 spin_unlock(&pkt
->lock
);
1047 if (pkt
->cache_valid
) {
1048 pkt_dbg(2, pd
, "zone %llx cached\n",
1049 (unsigned long long)pkt
->sector
);
1054 * Schedule reads for missing parts of the packet.
1056 for (f
= 0; f
< pkt
->frames
; f
++) {
1062 bio
= pkt
->r_bios
[f
];
1064 bio
->bi_iter
.bi_sector
= pkt
->sector
+ f
* (CD_FRAMESIZE
>> 9);
1065 bio
->bi_bdev
= pd
->bdev
;
1066 bio
->bi_end_io
= pkt_end_io_read
;
1067 bio
->bi_private
= pkt
;
1069 p
= (f
* CD_FRAMESIZE
) / PAGE_SIZE
;
1070 offset
= (f
* CD_FRAMESIZE
) % PAGE_SIZE
;
1071 pkt_dbg(2, pd
, "Adding frame %d, page:%p offs:%d\n",
1072 f
, pkt
->pages
[p
], offset
);
1073 if (!bio_add_page(bio
, pkt
->pages
[p
], CD_FRAMESIZE
, offset
))
1076 atomic_inc(&pkt
->io_wait
);
1078 pkt_queue_bio(pd
, bio
);
1083 pkt_dbg(2, pd
, "need %d frames for zone %llx\n",
1084 frames_read
, (unsigned long long)pkt
->sector
);
1085 pd
->stats
.pkt_started
++;
1086 pd
->stats
.secs_rg
+= frames_read
* (CD_FRAMESIZE
>> 9);
1090 * Find a packet matching zone, or the least recently used packet if
1091 * there is no match.
1093 static struct packet_data
*pkt_get_packet_data(struct pktcdvd_device
*pd
, int zone
)
1095 struct packet_data
*pkt
;
1097 list_for_each_entry(pkt
, &pd
->cdrw
.pkt_free_list
, list
) {
1098 if (pkt
->sector
== zone
|| pkt
->list
.next
== &pd
->cdrw
.pkt_free_list
) {
1099 list_del_init(&pkt
->list
);
1100 if (pkt
->sector
!= zone
)
1101 pkt
->cache_valid
= 0;
1109 static void pkt_put_packet_data(struct pktcdvd_device
*pd
, struct packet_data
*pkt
)
1111 if (pkt
->cache_valid
) {
1112 list_add(&pkt
->list
, &pd
->cdrw
.pkt_free_list
);
1114 list_add_tail(&pkt
->list
, &pd
->cdrw
.pkt_free_list
);
1119 * recover a failed write, query for relocation if possible
1121 * returns 1 if recovery is possible, or 0 if not
1124 static int pkt_start_recovery(struct packet_data
*pkt
)
1127 * FIXME. We need help from the file system to implement
1128 * recovery handling.
1132 struct request
*rq
= pkt
->rq
;
1133 struct pktcdvd_device
*pd
= rq
->rq_disk
->private_data
;
1134 struct block_device
*pkt_bdev
;
1135 struct super_block
*sb
= NULL
;
1136 unsigned long old_block
, new_block
;
1137 sector_t new_sector
;
1139 pkt_bdev
= bdget(kdev_t_to_nr(pd
->pkt_dev
));
1141 sb
= get_super(pkt_bdev
);
1148 if (!sb
->s_op
->relocate_blocks
)
1151 old_block
= pkt
->sector
/ (CD_FRAMESIZE
>> 9);
1152 if (sb
->s_op
->relocate_blocks(sb
, old_block
, &new_block
))
1155 new_sector
= new_block
* (CD_FRAMESIZE
>> 9);
1156 pkt
->sector
= new_sector
;
1158 bio_reset(pkt
->bio
);
1159 pkt
->bio
->bi_bdev
= pd
->bdev
;
1160 pkt
->bio
->bi_rw
= REQ_WRITE
;
1161 pkt
->bio
->bi_iter
.bi_sector
= new_sector
;
1162 pkt
->bio
->bi_iter
.bi_size
= pkt
->frames
* CD_FRAMESIZE
;
1163 pkt
->bio
->bi_vcnt
= pkt
->frames
;
1165 pkt
->bio
->bi_end_io
= pkt_end_io_packet_write
;
1166 pkt
->bio
->bi_private
= pkt
;
1177 static inline void pkt_set_state(struct packet_data
*pkt
, enum packet_data_state state
)
1179 #if PACKET_DEBUG > 1
1180 static const char *state_name
[] = {
1181 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1183 enum packet_data_state old_state
= pkt
->state
;
1184 pkt_dbg(2, pd
, "pkt %2d : s=%6llx %s -> %s\n",
1185 pkt
->id
, (unsigned long long)pkt
->sector
,
1186 state_name
[old_state
], state_name
[state
]);
1192 * Scan the work queue to see if we can start a new packet.
1193 * returns non-zero if any work was done.
1195 static int pkt_handle_queue(struct pktcdvd_device
*pd
)
1197 struct packet_data
*pkt
, *p
;
1198 struct bio
*bio
= NULL
;
1199 sector_t zone
= 0; /* Suppress gcc warning */
1200 struct pkt_rb_node
*node
, *first_node
;
1204 atomic_set(&pd
->scan_queue
, 0);
1206 if (list_empty(&pd
->cdrw
.pkt_free_list
)) {
1207 pkt_dbg(2, pd
, "no pkt\n");
1212 * Try to find a zone we are not already working on.
1214 spin_lock(&pd
->lock
);
1215 first_node
= pkt_rbtree_find(pd
, pd
->current_sector
);
1217 n
= rb_first(&pd
->bio_queue
);
1219 first_node
= rb_entry(n
, struct pkt_rb_node
, rb_node
);
1224 zone
= get_zone(bio
->bi_iter
.bi_sector
, pd
);
1225 list_for_each_entry(p
, &pd
->cdrw
.pkt_active_list
, list
) {
1226 if (p
->sector
== zone
) {
1233 node
= pkt_rbtree_next(node
);
1235 n
= rb_first(&pd
->bio_queue
);
1237 node
= rb_entry(n
, struct pkt_rb_node
, rb_node
);
1239 if (node
== first_node
)
1242 spin_unlock(&pd
->lock
);
1244 pkt_dbg(2, pd
, "no bio\n");
1248 pkt
= pkt_get_packet_data(pd
, zone
);
1250 pd
->current_sector
= zone
+ pd
->settings
.size
;
1252 BUG_ON(pkt
->frames
!= pd
->settings
.size
>> 2);
1253 pkt
->write_size
= 0;
1256 * Scan work queue for bios in the same zone and link them
1259 spin_lock(&pd
->lock
);
1260 pkt_dbg(2, pd
, "looking for zone %llx\n", (unsigned long long)zone
);
1261 while ((node
= pkt_rbtree_find(pd
, zone
)) != NULL
) {
1263 pkt_dbg(2, pd
, "found zone=%llx\n", (unsigned long long)
1264 get_zone(bio
->bi_iter
.bi_sector
, pd
));
1265 if (get_zone(bio
->bi_iter
.bi_sector
, pd
) != zone
)
1267 pkt_rbtree_erase(pd
, node
);
1268 spin_lock(&pkt
->lock
);
1269 bio_list_add(&pkt
->orig_bios
, bio
);
1270 pkt
->write_size
+= bio
->bi_iter
.bi_size
/ CD_FRAMESIZE
;
1271 spin_unlock(&pkt
->lock
);
1273 /* check write congestion marks, and if bio_queue_size is
1274 below, wake up any waiters */
1275 wakeup
= (pd
->write_congestion_on
> 0
1276 && pd
->bio_queue_size
<= pd
->write_congestion_off
);
1277 spin_unlock(&pd
->lock
);
1279 clear_bdi_congested(&pd
->disk
->queue
->backing_dev_info
,
1283 pkt
->sleep_time
= max(PACKET_WAIT_TIME
, 1);
1284 pkt_set_state(pkt
, PACKET_WAITING_STATE
);
1285 atomic_set(&pkt
->run_sm
, 1);
1287 spin_lock(&pd
->cdrw
.active_list_lock
);
1288 list_add(&pkt
->list
, &pd
->cdrw
.pkt_active_list
);
1289 spin_unlock(&pd
->cdrw
.active_list_lock
);
1295 * Assemble a bio to write one packet and queue the bio for processing
1296 * by the underlying block device.
1298 static void pkt_start_write(struct pktcdvd_device
*pd
, struct packet_data
*pkt
)
1301 struct bio_vec
*bvec
= pkt
->w_bio
->bi_io_vec
;
1303 bio_reset(pkt
->w_bio
);
1304 pkt
->w_bio
->bi_iter
.bi_sector
= pkt
->sector
;
1305 pkt
->w_bio
->bi_bdev
= pd
->bdev
;
1306 pkt
->w_bio
->bi_end_io
= pkt_end_io_packet_write
;
1307 pkt
->w_bio
->bi_private
= pkt
;
1310 for (f
= 0; f
< pkt
->frames
; f
++) {
1311 bvec
[f
].bv_page
= pkt
->pages
[(f
* CD_FRAMESIZE
) / PAGE_SIZE
];
1312 bvec
[f
].bv_offset
= (f
* CD_FRAMESIZE
) % PAGE_SIZE
;
1313 if (!bio_add_page(pkt
->w_bio
, bvec
[f
].bv_page
, CD_FRAMESIZE
, bvec
[f
].bv_offset
))
1316 pkt_dbg(2, pd
, "vcnt=%d\n", pkt
->w_bio
->bi_vcnt
);
1319 * Fill-in bvec with data from orig_bios.
1321 spin_lock(&pkt
->lock
);
1322 bio_copy_data(pkt
->w_bio
, pkt
->orig_bios
.head
);
1324 pkt_set_state(pkt
, PACKET_WRITE_WAIT_STATE
);
1325 spin_unlock(&pkt
->lock
);
1327 pkt_dbg(2, pd
, "Writing %d frames for zone %llx\n",
1328 pkt
->write_size
, (unsigned long long)pkt
->sector
);
1330 if (test_bit(PACKET_MERGE_SEGS
, &pd
->flags
) || (pkt
->write_size
< pkt
->frames
)) {
1331 pkt_make_local_copy(pkt
, bvec
);
1332 pkt
->cache_valid
= 1;
1334 pkt
->cache_valid
= 0;
1337 /* Start the write request */
1338 atomic_set(&pkt
->io_wait
, 1);
1339 pkt
->w_bio
->bi_rw
= WRITE
;
1340 pkt_queue_bio(pd
, pkt
->w_bio
);
1343 static void pkt_finish_packet(struct packet_data
*pkt
, int uptodate
)
1348 pkt
->cache_valid
= 0;
1350 /* Finish all bios corresponding to this packet */
1351 while ((bio
= bio_list_pop(&pkt
->orig_bios
)))
1352 bio_endio(bio
, uptodate
? 0 : -EIO
);
1355 static void pkt_run_state_machine(struct pktcdvd_device
*pd
, struct packet_data
*pkt
)
1359 pkt_dbg(2, pd
, "pkt %d\n", pkt
->id
);
1362 switch (pkt
->state
) {
1363 case PACKET_WAITING_STATE
:
1364 if ((pkt
->write_size
< pkt
->frames
) && (pkt
->sleep_time
> 0))
1367 pkt
->sleep_time
= 0;
1368 pkt_gather_data(pd
, pkt
);
1369 pkt_set_state(pkt
, PACKET_READ_WAIT_STATE
);
1372 case PACKET_READ_WAIT_STATE
:
1373 if (atomic_read(&pkt
->io_wait
) > 0)
1376 if (atomic_read(&pkt
->io_errors
) > 0) {
1377 pkt_set_state(pkt
, PACKET_RECOVERY_STATE
);
1379 pkt_start_write(pd
, pkt
);
1383 case PACKET_WRITE_WAIT_STATE
:
1384 if (atomic_read(&pkt
->io_wait
) > 0)
1387 if (test_bit(BIO_UPTODATE
, &pkt
->w_bio
->bi_flags
)) {
1388 pkt_set_state(pkt
, PACKET_FINISHED_STATE
);
1390 pkt_set_state(pkt
, PACKET_RECOVERY_STATE
);
1394 case PACKET_RECOVERY_STATE
:
1395 if (pkt_start_recovery(pkt
)) {
1396 pkt_start_write(pd
, pkt
);
1398 pkt_dbg(2, pd
, "No recovery possible\n");
1399 pkt_set_state(pkt
, PACKET_FINISHED_STATE
);
1403 case PACKET_FINISHED_STATE
:
1404 uptodate
= test_bit(BIO_UPTODATE
, &pkt
->w_bio
->bi_flags
);
1405 pkt_finish_packet(pkt
, uptodate
);
1415 static void pkt_handle_packets(struct pktcdvd_device
*pd
)
1417 struct packet_data
*pkt
, *next
;
1420 * Run state machine for active packets
1422 list_for_each_entry(pkt
, &pd
->cdrw
.pkt_active_list
, list
) {
1423 if (atomic_read(&pkt
->run_sm
) > 0) {
1424 atomic_set(&pkt
->run_sm
, 0);
1425 pkt_run_state_machine(pd
, pkt
);
1430 * Move no longer active packets to the free list
1432 spin_lock(&pd
->cdrw
.active_list_lock
);
1433 list_for_each_entry_safe(pkt
, next
, &pd
->cdrw
.pkt_active_list
, list
) {
1434 if (pkt
->state
== PACKET_FINISHED_STATE
) {
1435 list_del(&pkt
->list
);
1436 pkt_put_packet_data(pd
, pkt
);
1437 pkt_set_state(pkt
, PACKET_IDLE_STATE
);
1438 atomic_set(&pd
->scan_queue
, 1);
1441 spin_unlock(&pd
->cdrw
.active_list_lock
);
1444 static void pkt_count_states(struct pktcdvd_device
*pd
, int *states
)
1446 struct packet_data
*pkt
;
1449 for (i
= 0; i
< PACKET_NUM_STATES
; i
++)
1452 spin_lock(&pd
->cdrw
.active_list_lock
);
1453 list_for_each_entry(pkt
, &pd
->cdrw
.pkt_active_list
, list
) {
1454 states
[pkt
->state
]++;
1456 spin_unlock(&pd
->cdrw
.active_list_lock
);
1460 * kcdrwd is woken up when writes have been queued for one of our
1461 * registered devices
1463 static int kcdrwd(void *foobar
)
1465 struct pktcdvd_device
*pd
= foobar
;
1466 struct packet_data
*pkt
;
1467 long min_sleep_time
, residue
;
1469 set_user_nice(current
, MIN_NICE
);
1473 DECLARE_WAITQUEUE(wait
, current
);
1476 * Wait until there is something to do
1478 add_wait_queue(&pd
->wqueue
, &wait
);
1480 set_current_state(TASK_INTERRUPTIBLE
);
1482 /* Check if we need to run pkt_handle_queue */
1483 if (atomic_read(&pd
->scan_queue
) > 0)
1486 /* Check if we need to run the state machine for some packet */
1487 list_for_each_entry(pkt
, &pd
->cdrw
.pkt_active_list
, list
) {
1488 if (atomic_read(&pkt
->run_sm
) > 0)
1492 /* Check if we need to process the iosched queues */
1493 if (atomic_read(&pd
->iosched
.attention
) != 0)
1496 /* Otherwise, go to sleep */
1497 if (PACKET_DEBUG
> 1) {
1498 int states
[PACKET_NUM_STATES
];
1499 pkt_count_states(pd
, states
);
1500 pkt_dbg(2, pd
, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1501 states
[0], states
[1], states
[2],
1502 states
[3], states
[4], states
[5]);
1505 min_sleep_time
= MAX_SCHEDULE_TIMEOUT
;
1506 list_for_each_entry(pkt
, &pd
->cdrw
.pkt_active_list
, list
) {
1507 if (pkt
->sleep_time
&& pkt
->sleep_time
< min_sleep_time
)
1508 min_sleep_time
= pkt
->sleep_time
;
1511 pkt_dbg(2, pd
, "sleeping\n");
1512 residue
= schedule_timeout(min_sleep_time
);
1513 pkt_dbg(2, pd
, "wake up\n");
1515 /* make swsusp happy with our thread */
1518 list_for_each_entry(pkt
, &pd
->cdrw
.pkt_active_list
, list
) {
1519 if (!pkt
->sleep_time
)
1521 pkt
->sleep_time
-= min_sleep_time
- residue
;
1522 if (pkt
->sleep_time
<= 0) {
1523 pkt
->sleep_time
= 0;
1524 atomic_inc(&pkt
->run_sm
);
1528 if (kthread_should_stop())
1532 set_current_state(TASK_RUNNING
);
1533 remove_wait_queue(&pd
->wqueue
, &wait
);
1535 if (kthread_should_stop())
1539 * if pkt_handle_queue returns true, we can queue
1542 while (pkt_handle_queue(pd
))
1546 * Handle packet state machine
1548 pkt_handle_packets(pd
);
1551 * Handle iosched queues
1553 pkt_iosched_process_queue(pd
);
1559 static void pkt_print_settings(struct pktcdvd_device
*pd
)
1561 pkt_info(pd
, "%s packets, %u blocks, Mode-%c disc\n",
1562 pd
->settings
.fp
? "Fixed" : "Variable",
1563 pd
->settings
.size
>> 2,
1564 pd
->settings
.block_mode
== 8 ? '1' : '2');
1567 static int pkt_mode_sense(struct pktcdvd_device
*pd
, struct packet_command
*cgc
, int page_code
, int page_control
)
1569 memset(cgc
->cmd
, 0, sizeof(cgc
->cmd
));
1571 cgc
->cmd
[0] = GPCMD_MODE_SENSE_10
;
1572 cgc
->cmd
[2] = page_code
| (page_control
<< 6);
1573 cgc
->cmd
[7] = cgc
->buflen
>> 8;
1574 cgc
->cmd
[8] = cgc
->buflen
& 0xff;
1575 cgc
->data_direction
= CGC_DATA_READ
;
1576 return pkt_generic_packet(pd
, cgc
);
1579 static int pkt_mode_select(struct pktcdvd_device
*pd
, struct packet_command
*cgc
)
1581 memset(cgc
->cmd
, 0, sizeof(cgc
->cmd
));
1582 memset(cgc
->buffer
, 0, 2);
1583 cgc
->cmd
[0] = GPCMD_MODE_SELECT_10
;
1584 cgc
->cmd
[1] = 0x10; /* PF */
1585 cgc
->cmd
[7] = cgc
->buflen
>> 8;
1586 cgc
->cmd
[8] = cgc
->buflen
& 0xff;
1587 cgc
->data_direction
= CGC_DATA_WRITE
;
1588 return pkt_generic_packet(pd
, cgc
);
1591 static int pkt_get_disc_info(struct pktcdvd_device
*pd
, disc_information
*di
)
1593 struct packet_command cgc
;
1596 /* set up command and get the disc info */
1597 init_cdrom_command(&cgc
, di
, sizeof(*di
), CGC_DATA_READ
);
1598 cgc
.cmd
[0] = GPCMD_READ_DISC_INFO
;
1599 cgc
.cmd
[8] = cgc
.buflen
= 2;
1602 if ((ret
= pkt_generic_packet(pd
, &cgc
)))
1605 /* not all drives have the same disc_info length, so requeue
1606 * packet with the length the drive tells us it can supply
1608 cgc
.buflen
= be16_to_cpu(di
->disc_information_length
) +
1609 sizeof(di
->disc_information_length
);
1611 if (cgc
.buflen
> sizeof(disc_information
))
1612 cgc
.buflen
= sizeof(disc_information
);
1614 cgc
.cmd
[8] = cgc
.buflen
;
1615 return pkt_generic_packet(pd
, &cgc
);
1618 static int pkt_get_track_info(struct pktcdvd_device
*pd
, __u16 track
, __u8 type
, track_information
*ti
)
1620 struct packet_command cgc
;
1623 init_cdrom_command(&cgc
, ti
, 8, CGC_DATA_READ
);
1624 cgc
.cmd
[0] = GPCMD_READ_TRACK_RZONE_INFO
;
1625 cgc
.cmd
[1] = type
& 3;
1626 cgc
.cmd
[4] = (track
& 0xff00) >> 8;
1627 cgc
.cmd
[5] = track
& 0xff;
1631 if ((ret
= pkt_generic_packet(pd
, &cgc
)))
1634 cgc
.buflen
= be16_to_cpu(ti
->track_information_length
) +
1635 sizeof(ti
->track_information_length
);
1637 if (cgc
.buflen
> sizeof(track_information
))
1638 cgc
.buflen
= sizeof(track_information
);
1640 cgc
.cmd
[8] = cgc
.buflen
;
1641 return pkt_generic_packet(pd
, &cgc
);
1644 static noinline_for_stack
int pkt_get_last_written(struct pktcdvd_device
*pd
,
1647 disc_information di
;
1648 track_information ti
;
1652 if ((ret
= pkt_get_disc_info(pd
, &di
)))
1655 last_track
= (di
.last_track_msb
<< 8) | di
.last_track_lsb
;
1656 if ((ret
= pkt_get_track_info(pd
, last_track
, 1, &ti
)))
1659 /* if this track is blank, try the previous. */
1662 if ((ret
= pkt_get_track_info(pd
, last_track
, 1, &ti
)))
1666 /* if last recorded field is valid, return it. */
1668 *last_written
= be32_to_cpu(ti
.last_rec_address
);
1670 /* make it up instead */
1671 *last_written
= be32_to_cpu(ti
.track_start
) +
1672 be32_to_cpu(ti
.track_size
);
1674 *last_written
-= (be32_to_cpu(ti
.free_blocks
) + 7);
1680 * write mode select package based on pd->settings
1682 static noinline_for_stack
int pkt_set_write_settings(struct pktcdvd_device
*pd
)
1684 struct packet_command cgc
;
1685 struct request_sense sense
;
1686 write_param_page
*wp
;
1690 /* doesn't apply to DVD+RW or DVD-RAM */
1691 if ((pd
->mmc3_profile
== 0x1a) || (pd
->mmc3_profile
== 0x12))
1694 memset(buffer
, 0, sizeof(buffer
));
1695 init_cdrom_command(&cgc
, buffer
, sizeof(*wp
), CGC_DATA_READ
);
1697 if ((ret
= pkt_mode_sense(pd
, &cgc
, GPMODE_WRITE_PARMS_PAGE
, 0))) {
1698 pkt_dump_sense(pd
, &cgc
);
1702 size
= 2 + ((buffer
[0] << 8) | (buffer
[1] & 0xff));
1703 pd
->mode_offset
= (buffer
[6] << 8) | (buffer
[7] & 0xff);
1704 if (size
> sizeof(buffer
))
1705 size
= sizeof(buffer
);
1710 init_cdrom_command(&cgc
, buffer
, size
, CGC_DATA_READ
);
1712 if ((ret
= pkt_mode_sense(pd
, &cgc
, GPMODE_WRITE_PARMS_PAGE
, 0))) {
1713 pkt_dump_sense(pd
, &cgc
);
1718 * write page is offset header + block descriptor length
1720 wp
= (write_param_page
*) &buffer
[sizeof(struct mode_page_header
) + pd
->mode_offset
];
1722 wp
->fp
= pd
->settings
.fp
;
1723 wp
->track_mode
= pd
->settings
.track_mode
;
1724 wp
->write_type
= pd
->settings
.write_type
;
1725 wp
->data_block_type
= pd
->settings
.block_mode
;
1727 wp
->multi_session
= 0;
1729 #ifdef PACKET_USE_LS
1734 if (wp
->data_block_type
== PACKET_BLOCK_MODE1
) {
1735 wp
->session_format
= 0;
1737 } else if (wp
->data_block_type
== PACKET_BLOCK_MODE2
) {
1738 wp
->session_format
= 0x20;
1742 memcpy(&wp
->mcn
[1], PACKET_MCN
, sizeof(wp
->mcn
) - 1);
1748 pkt_err(pd
, "write mode wrong %d\n", wp
->data_block_type
);
1751 wp
->packet_size
= cpu_to_be32(pd
->settings
.size
>> 2);
1753 cgc
.buflen
= cgc
.cmd
[8] = size
;
1754 if ((ret
= pkt_mode_select(pd
, &cgc
))) {
1755 pkt_dump_sense(pd
, &cgc
);
1759 pkt_print_settings(pd
);
1764 * 1 -- we can write to this track, 0 -- we can't
1766 static int pkt_writable_track(struct pktcdvd_device
*pd
, track_information
*ti
)
1768 switch (pd
->mmc3_profile
) {
1769 case 0x1a: /* DVD+RW */
1770 case 0x12: /* DVD-RAM */
1771 /* The track is always writable on DVD+RW/DVD-RAM */
1777 if (!ti
->packet
|| !ti
->fp
)
1781 * "good" settings as per Mt Fuji.
1783 if (ti
->rt
== 0 && ti
->blank
== 0)
1786 if (ti
->rt
== 0 && ti
->blank
== 1)
1789 if (ti
->rt
== 1 && ti
->blank
== 0)
1792 pkt_err(pd
, "bad state %d-%d-%d\n", ti
->rt
, ti
->blank
, ti
->packet
);
1797 * 1 -- we can write to this disc, 0 -- we can't
1799 static int pkt_writable_disc(struct pktcdvd_device
*pd
, disc_information
*di
)
1801 switch (pd
->mmc3_profile
) {
1802 case 0x0a: /* CD-RW */
1803 case 0xffff: /* MMC3 not supported */
1805 case 0x1a: /* DVD+RW */
1806 case 0x13: /* DVD-RW */
1807 case 0x12: /* DVD-RAM */
1810 pkt_dbg(2, pd
, "Wrong disc profile (%x)\n",
1816 * for disc type 0xff we should probably reserve a new track.
1817 * but i'm not sure, should we leave this to user apps? probably.
1819 if (di
->disc_type
== 0xff) {
1820 pkt_notice(pd
, "unknown disc - no track?\n");
1824 if (di
->disc_type
!= 0x20 && di
->disc_type
!= 0) {
1825 pkt_err(pd
, "wrong disc type (%x)\n", di
->disc_type
);
1829 if (di
->erasable
== 0) {
1830 pkt_notice(pd
, "disc not erasable\n");
1834 if (di
->border_status
== PACKET_SESSION_RESERVED
) {
1835 pkt_err(pd
, "can't write to last track (reserved)\n");
1842 static noinline_for_stack
int pkt_probe_settings(struct pktcdvd_device
*pd
)
1844 struct packet_command cgc
;
1845 unsigned char buf
[12];
1846 disc_information di
;
1847 track_information ti
;
1850 init_cdrom_command(&cgc
, buf
, sizeof(buf
), CGC_DATA_READ
);
1851 cgc
.cmd
[0] = GPCMD_GET_CONFIGURATION
;
1853 ret
= pkt_generic_packet(pd
, &cgc
);
1854 pd
->mmc3_profile
= ret
? 0xffff : buf
[6] << 8 | buf
[7];
1856 memset(&di
, 0, sizeof(disc_information
));
1857 memset(&ti
, 0, sizeof(track_information
));
1859 if ((ret
= pkt_get_disc_info(pd
, &di
))) {
1860 pkt_err(pd
, "failed get_disc\n");
1864 if (!pkt_writable_disc(pd
, &di
))
1867 pd
->type
= di
.erasable
? PACKET_CDRW
: PACKET_CDR
;
1869 track
= 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1870 if ((ret
= pkt_get_track_info(pd
, track
, 1, &ti
))) {
1871 pkt_err(pd
, "failed get_track\n");
1875 if (!pkt_writable_track(pd
, &ti
)) {
1876 pkt_err(pd
, "can't write to this track\n");
1881 * we keep packet size in 512 byte units, makes it easier to
1882 * deal with request calculations.
1884 pd
->settings
.size
= be32_to_cpu(ti
.fixed_packet_size
) << 2;
1885 if (pd
->settings
.size
== 0) {
1886 pkt_notice(pd
, "detected zero packet size!\n");
1889 if (pd
->settings
.size
> PACKET_MAX_SECTORS
) {
1890 pkt_err(pd
, "packet size is too big\n");
1893 pd
->settings
.fp
= ti
.fp
;
1894 pd
->offset
= (be32_to_cpu(ti
.track_start
) << 2) & (pd
->settings
.size
- 1);
1897 pd
->nwa
= be32_to_cpu(ti
.next_writable
);
1898 set_bit(PACKET_NWA_VALID
, &pd
->flags
);
1902 * in theory we could use lra on -RW media as well and just zero
1903 * blocks that haven't been written yet, but in practice that
1904 * is just a no-go. we'll use that for -R, naturally.
1907 pd
->lra
= be32_to_cpu(ti
.last_rec_address
);
1908 set_bit(PACKET_LRA_VALID
, &pd
->flags
);
1910 pd
->lra
= 0xffffffff;
1911 set_bit(PACKET_LRA_VALID
, &pd
->flags
);
1917 pd
->settings
.link_loss
= 7;
1918 pd
->settings
.write_type
= 0; /* packet */
1919 pd
->settings
.track_mode
= ti
.track_mode
;
1922 * mode1 or mode2 disc
1924 switch (ti
.data_mode
) {
1926 pd
->settings
.block_mode
= PACKET_BLOCK_MODE1
;
1929 pd
->settings
.block_mode
= PACKET_BLOCK_MODE2
;
1932 pkt_err(pd
, "unknown data mode\n");
1939 * enable/disable write caching on drive
1941 static noinline_for_stack
int pkt_write_caching(struct pktcdvd_device
*pd
,
1944 struct packet_command cgc
;
1945 struct request_sense sense
;
1946 unsigned char buf
[64];
1949 init_cdrom_command(&cgc
, buf
, sizeof(buf
), CGC_DATA_READ
);
1951 cgc
.buflen
= pd
->mode_offset
+ 12;
1954 * caching mode page might not be there, so quiet this command
1958 if ((ret
= pkt_mode_sense(pd
, &cgc
, GPMODE_WCACHING_PAGE
, 0)))
1961 buf
[pd
->mode_offset
+ 10] |= (!!set
<< 2);
1963 cgc
.buflen
= cgc
.cmd
[8] = 2 + ((buf
[0] << 8) | (buf
[1] & 0xff));
1964 ret
= pkt_mode_select(pd
, &cgc
);
1966 pkt_err(pd
, "write caching control failed\n");
1967 pkt_dump_sense(pd
, &cgc
);
1968 } else if (!ret
&& set
)
1969 pkt_notice(pd
, "enabled write caching\n");
1973 static int pkt_lock_door(struct pktcdvd_device
*pd
, int lockflag
)
1975 struct packet_command cgc
;
1977 init_cdrom_command(&cgc
, NULL
, 0, CGC_DATA_NONE
);
1978 cgc
.cmd
[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL
;
1979 cgc
.cmd
[4] = lockflag
? 1 : 0;
1980 return pkt_generic_packet(pd
, &cgc
);
1984 * Returns drive maximum write speed
1986 static noinline_for_stack
int pkt_get_max_speed(struct pktcdvd_device
*pd
,
1987 unsigned *write_speed
)
1989 struct packet_command cgc
;
1990 struct request_sense sense
;
1991 unsigned char buf
[256+18];
1992 unsigned char *cap_buf
;
1995 cap_buf
= &buf
[sizeof(struct mode_page_header
) + pd
->mode_offset
];
1996 init_cdrom_command(&cgc
, buf
, sizeof(buf
), CGC_DATA_UNKNOWN
);
1999 ret
= pkt_mode_sense(pd
, &cgc
, GPMODE_CAPABILITIES_PAGE
, 0);
2001 cgc
.buflen
= pd
->mode_offset
+ cap_buf
[1] + 2 +
2002 sizeof(struct mode_page_header
);
2003 ret
= pkt_mode_sense(pd
, &cgc
, GPMODE_CAPABILITIES_PAGE
, 0);
2005 pkt_dump_sense(pd
, &cgc
);
2010 offset
= 20; /* Obsoleted field, used by older drives */
2011 if (cap_buf
[1] >= 28)
2012 offset
= 28; /* Current write speed selected */
2013 if (cap_buf
[1] >= 30) {
2014 /* If the drive reports at least one "Logical Unit Write
2015 * Speed Performance Descriptor Block", use the information
2016 * in the first block. (contains the highest speed)
2018 int num_spdb
= (cap_buf
[30] << 8) + cap_buf
[31];
2023 *write_speed
= (cap_buf
[offset
] << 8) | cap_buf
[offset
+ 1];
2027 /* These tables from cdrecord - I don't have orange book */
2028 /* standard speed CD-RW (1-4x) */
2029 static char clv_to_speed
[16] = {
2030 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
2031 0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2033 /* high speed CD-RW (-10x) */
2034 static char hs_clv_to_speed
[16] = {
2035 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
2036 0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2038 /* ultra high speed CD-RW */
2039 static char us_clv_to_speed
[16] = {
2040 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
2041 0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2045 * reads the maximum media speed from ATIP
2047 static noinline_for_stack
int pkt_media_speed(struct pktcdvd_device
*pd
,
2050 struct packet_command cgc
;
2051 struct request_sense sense
;
2052 unsigned char buf
[64];
2053 unsigned int size
, st
, sp
;
2056 init_cdrom_command(&cgc
, buf
, 2, CGC_DATA_READ
);
2058 cgc
.cmd
[0] = GPCMD_READ_TOC_PMA_ATIP
;
2060 cgc
.cmd
[2] = 4; /* READ ATIP */
2062 ret
= pkt_generic_packet(pd
, &cgc
);
2064 pkt_dump_sense(pd
, &cgc
);
2067 size
= ((unsigned int) buf
[0]<<8) + buf
[1] + 2;
2068 if (size
> sizeof(buf
))
2071 init_cdrom_command(&cgc
, buf
, size
, CGC_DATA_READ
);
2073 cgc
.cmd
[0] = GPCMD_READ_TOC_PMA_ATIP
;
2077 ret
= pkt_generic_packet(pd
, &cgc
);
2079 pkt_dump_sense(pd
, &cgc
);
2083 if (!(buf
[6] & 0x40)) {
2084 pkt_notice(pd
, "disc type is not CD-RW\n");
2087 if (!(buf
[6] & 0x4)) {
2088 pkt_notice(pd
, "A1 values on media are not valid, maybe not CDRW?\n");
2092 st
= (buf
[6] >> 3) & 0x7; /* disc sub-type */
2094 sp
= buf
[16] & 0xf; /* max speed from ATIP A1 field */
2096 /* Info from cdrecord */
2098 case 0: /* standard speed */
2099 *speed
= clv_to_speed
[sp
];
2101 case 1: /* high speed */
2102 *speed
= hs_clv_to_speed
[sp
];
2104 case 2: /* ultra high speed */
2105 *speed
= us_clv_to_speed
[sp
];
2108 pkt_notice(pd
, "unknown disc sub-type %d\n", st
);
2112 pkt_info(pd
, "maximum media speed: %d\n", *speed
);
2115 pkt_notice(pd
, "unknown speed %d for sub-type %d\n", sp
, st
);
2120 static noinline_for_stack
int pkt_perform_opc(struct pktcdvd_device
*pd
)
2122 struct packet_command cgc
;
2123 struct request_sense sense
;
2126 pkt_dbg(2, pd
, "Performing OPC\n");
2128 init_cdrom_command(&cgc
, NULL
, 0, CGC_DATA_NONE
);
2130 cgc
.timeout
= 60*HZ
;
2131 cgc
.cmd
[0] = GPCMD_SEND_OPC
;
2133 if ((ret
= pkt_generic_packet(pd
, &cgc
)))
2134 pkt_dump_sense(pd
, &cgc
);
2138 static int pkt_open_write(struct pktcdvd_device
*pd
)
2141 unsigned int write_speed
, media_write_speed
, read_speed
;
2143 if ((ret
= pkt_probe_settings(pd
))) {
2144 pkt_dbg(2, pd
, "failed probe\n");
2148 if ((ret
= pkt_set_write_settings(pd
))) {
2149 pkt_dbg(1, pd
, "failed saving write settings\n");
2153 pkt_write_caching(pd
, USE_WCACHING
);
2155 if ((ret
= pkt_get_max_speed(pd
, &write_speed
)))
2156 write_speed
= 16 * 177;
2157 switch (pd
->mmc3_profile
) {
2158 case 0x13: /* DVD-RW */
2159 case 0x1a: /* DVD+RW */
2160 case 0x12: /* DVD-RAM */
2161 pkt_dbg(1, pd
, "write speed %ukB/s\n", write_speed
);
2164 if ((ret
= pkt_media_speed(pd
, &media_write_speed
)))
2165 media_write_speed
= 16;
2166 write_speed
= min(write_speed
, media_write_speed
* 177);
2167 pkt_dbg(1, pd
, "write speed %ux\n", write_speed
/ 176);
2170 read_speed
= write_speed
;
2172 if ((ret
= pkt_set_speed(pd
, write_speed
, read_speed
))) {
2173 pkt_dbg(1, pd
, "couldn't set write speed\n");
2176 pd
->write_speed
= write_speed
;
2177 pd
->read_speed
= read_speed
;
2179 if ((ret
= pkt_perform_opc(pd
))) {
2180 pkt_dbg(1, pd
, "Optimum Power Calibration failed\n");
2187 * called at open time.
2189 static int pkt_open_dev(struct pktcdvd_device
*pd
, fmode_t write
)
2193 struct request_queue
*q
;
2196 * We need to re-open the cdrom device without O_NONBLOCK to be able
2197 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2198 * so bdget() can't fail.
2200 bdget(pd
->bdev
->bd_dev
);
2201 if ((ret
= blkdev_get(pd
->bdev
, FMODE_READ
| FMODE_EXCL
, pd
)))
2204 if ((ret
= pkt_get_last_written(pd
, &lba
))) {
2205 pkt_err(pd
, "pkt_get_last_written failed\n");
2209 set_capacity(pd
->disk
, lba
<< 2);
2210 set_capacity(pd
->bdev
->bd_disk
, lba
<< 2);
2211 bd_set_size(pd
->bdev
, (loff_t
)lba
<< 11);
2213 q
= bdev_get_queue(pd
->bdev
);
2215 if ((ret
= pkt_open_write(pd
)))
2218 * Some CDRW drives can not handle writes larger than one packet,
2219 * even if the size is a multiple of the packet size.
2221 spin_lock_irq(q
->queue_lock
);
2222 blk_queue_max_hw_sectors(q
, pd
->settings
.size
);
2223 spin_unlock_irq(q
->queue_lock
);
2224 set_bit(PACKET_WRITABLE
, &pd
->flags
);
2226 pkt_set_speed(pd
, MAX_SPEED
, MAX_SPEED
);
2227 clear_bit(PACKET_WRITABLE
, &pd
->flags
);
2230 if ((ret
= pkt_set_segment_merging(pd
, q
)))
2234 if (!pkt_grow_pktlist(pd
, CONFIG_CDROM_PKTCDVD_BUFFERS
)) {
2235 pkt_err(pd
, "not enough memory for buffers\n");
2239 pkt_info(pd
, "%lukB available on disc\n", lba
<< 1);
2245 blkdev_put(pd
->bdev
, FMODE_READ
| FMODE_EXCL
);
2251 * called when the device is closed. makes sure that the device flushes
2252 * the internal cache before we close.
2254 static void pkt_release_dev(struct pktcdvd_device
*pd
, int flush
)
2256 if (flush
&& pkt_flush_cache(pd
))
2257 pkt_dbg(1, pd
, "not flushing cache\n");
2259 pkt_lock_door(pd
, 0);
2261 pkt_set_speed(pd
, MAX_SPEED
, MAX_SPEED
);
2262 blkdev_put(pd
->bdev
, FMODE_READ
| FMODE_EXCL
);
2264 pkt_shrink_pktlist(pd
);
2267 static struct pktcdvd_device
*pkt_find_dev_from_minor(unsigned int dev_minor
)
2269 if (dev_minor
>= MAX_WRITERS
)
2271 return pkt_devs
[dev_minor
];
2274 static int pkt_open(struct block_device
*bdev
, fmode_t mode
)
2276 struct pktcdvd_device
*pd
= NULL
;
2279 mutex_lock(&pktcdvd_mutex
);
2280 mutex_lock(&ctl_mutex
);
2281 pd
= pkt_find_dev_from_minor(MINOR(bdev
->bd_dev
));
2286 BUG_ON(pd
->refcnt
< 0);
2289 if (pd
->refcnt
> 1) {
2290 if ((mode
& FMODE_WRITE
) &&
2291 !test_bit(PACKET_WRITABLE
, &pd
->flags
)) {
2296 ret
= pkt_open_dev(pd
, mode
& FMODE_WRITE
);
2300 * needed here as well, since ext2 (among others) may change
2301 * the blocksize at mount time
2303 set_blocksize(bdev
, CD_FRAMESIZE
);
2306 mutex_unlock(&ctl_mutex
);
2307 mutex_unlock(&pktcdvd_mutex
);
2313 mutex_unlock(&ctl_mutex
);
2314 mutex_unlock(&pktcdvd_mutex
);
2318 static void pkt_close(struct gendisk
*disk
, fmode_t mode
)
2320 struct pktcdvd_device
*pd
= disk
->private_data
;
2322 mutex_lock(&pktcdvd_mutex
);
2323 mutex_lock(&ctl_mutex
);
2325 BUG_ON(pd
->refcnt
< 0);
2326 if (pd
->refcnt
== 0) {
2327 int flush
= test_bit(PACKET_WRITABLE
, &pd
->flags
);
2328 pkt_release_dev(pd
, flush
);
2330 mutex_unlock(&ctl_mutex
);
2331 mutex_unlock(&pktcdvd_mutex
);
2335 static void pkt_end_io_read_cloned(struct bio
*bio
, int err
)
2337 struct packet_stacked_data
*psd
= bio
->bi_private
;
2338 struct pktcdvd_device
*pd
= psd
->pd
;
2341 bio_endio(psd
->bio
, err
);
2342 mempool_free(psd
, psd_pool
);
2343 pkt_bio_finished(pd
);
2346 static void pkt_make_request_read(struct pktcdvd_device
*pd
, struct bio
*bio
)
2348 struct bio
*cloned_bio
= bio_clone(bio
, GFP_NOIO
);
2349 struct packet_stacked_data
*psd
= mempool_alloc(psd_pool
, GFP_NOIO
);
2353 cloned_bio
->bi_bdev
= pd
->bdev
;
2354 cloned_bio
->bi_private
= psd
;
2355 cloned_bio
->bi_end_io
= pkt_end_io_read_cloned
;
2356 pd
->stats
.secs_r
+= bio_sectors(bio
);
2357 pkt_queue_bio(pd
, cloned_bio
);
2360 static void pkt_make_request_write(struct request_queue
*q
, struct bio
*bio
)
2362 struct pktcdvd_device
*pd
= q
->queuedata
;
2364 struct packet_data
*pkt
;
2365 int was_empty
, blocked_bio
;
2366 struct pkt_rb_node
*node
;
2368 zone
= get_zone(bio
->bi_iter
.bi_sector
, pd
);
2371 * If we find a matching packet in state WAITING or READ_WAIT, we can
2372 * just append this bio to that packet.
2374 spin_lock(&pd
->cdrw
.active_list_lock
);
2376 list_for_each_entry(pkt
, &pd
->cdrw
.pkt_active_list
, list
) {
2377 if (pkt
->sector
== zone
) {
2378 spin_lock(&pkt
->lock
);
2379 if ((pkt
->state
== PACKET_WAITING_STATE
) ||
2380 (pkt
->state
== PACKET_READ_WAIT_STATE
)) {
2381 bio_list_add(&pkt
->orig_bios
, bio
);
2383 bio
->bi_iter
.bi_size
/ CD_FRAMESIZE
;
2384 if ((pkt
->write_size
>= pkt
->frames
) &&
2385 (pkt
->state
== PACKET_WAITING_STATE
)) {
2386 atomic_inc(&pkt
->run_sm
);
2387 wake_up(&pd
->wqueue
);
2389 spin_unlock(&pkt
->lock
);
2390 spin_unlock(&pd
->cdrw
.active_list_lock
);
2395 spin_unlock(&pkt
->lock
);
2398 spin_unlock(&pd
->cdrw
.active_list_lock
);
2401 * Test if there is enough room left in the bio work queue
2402 * (queue size >= congestion on mark).
2403 * If not, wait till the work queue size is below the congestion off mark.
2405 spin_lock(&pd
->lock
);
2406 if (pd
->write_congestion_on
> 0
2407 && pd
->bio_queue_size
>= pd
->write_congestion_on
) {
2408 set_bdi_congested(&q
->backing_dev_info
, BLK_RW_ASYNC
);
2410 spin_unlock(&pd
->lock
);
2411 congestion_wait(BLK_RW_ASYNC
, HZ
);
2412 spin_lock(&pd
->lock
);
2413 } while(pd
->bio_queue_size
> pd
->write_congestion_off
);
2415 spin_unlock(&pd
->lock
);
2418 * No matching packet found. Store the bio in the work queue.
2420 node
= mempool_alloc(pd
->rb_pool
, GFP_NOIO
);
2422 spin_lock(&pd
->lock
);
2423 BUG_ON(pd
->bio_queue_size
< 0);
2424 was_empty
= (pd
->bio_queue_size
== 0);
2425 pkt_rbtree_insert(pd
, node
);
2426 spin_unlock(&pd
->lock
);
2429 * Wake up the worker thread.
2431 atomic_set(&pd
->scan_queue
, 1);
2433 /* This wake_up is required for correct operation */
2434 wake_up(&pd
->wqueue
);
2435 } else if (!list_empty(&pd
->cdrw
.pkt_free_list
) && !blocked_bio
) {
2437 * This wake up is not required for correct operation,
2438 * but improves performance in some cases.
2440 wake_up(&pd
->wqueue
);
2444 static void pkt_make_request(struct request_queue
*q
, struct bio
*bio
)
2446 struct pktcdvd_device
*pd
;
2447 char b
[BDEVNAME_SIZE
];
2452 pr_err("%s incorrect request queue\n",
2453 bdevname(bio
->bi_bdev
, b
));
2457 pkt_dbg(2, pd
, "start = %6llx stop = %6llx\n",
2458 (unsigned long long)bio
->bi_iter
.bi_sector
,
2459 (unsigned long long)bio_end_sector(bio
));
2462 * Clone READ bios so we can have our own bi_end_io callback.
2464 if (bio_data_dir(bio
) == READ
) {
2465 pkt_make_request_read(pd
, bio
);
2469 if (!test_bit(PACKET_WRITABLE
, &pd
->flags
)) {
2470 pkt_notice(pd
, "WRITE for ro device (%llu)\n",
2471 (unsigned long long)bio
->bi_iter
.bi_sector
);
2475 if (!bio
->bi_iter
.bi_size
|| (bio
->bi_iter
.bi_size
% CD_FRAMESIZE
)) {
2476 pkt_err(pd
, "wrong bio size\n");
2480 blk_queue_bounce(q
, &bio
);
2483 sector_t zone
= get_zone(bio
->bi_iter
.bi_sector
, pd
);
2484 sector_t last_zone
= get_zone(bio_end_sector(bio
) - 1, pd
);
2486 if (last_zone
!= zone
) {
2487 BUG_ON(last_zone
!= zone
+ pd
->settings
.size
);
2489 split
= bio_split(bio
, last_zone
-
2490 bio
->bi_iter
.bi_sector
,
2491 GFP_NOIO
, fs_bio_set
);
2492 bio_chain(split
, bio
);
2497 pkt_make_request_write(q
, split
);
2498 } while (split
!= bio
);
2507 static int pkt_merge_bvec(struct request_queue
*q
, struct bvec_merge_data
*bmd
,
2508 struct bio_vec
*bvec
)
2510 struct pktcdvd_device
*pd
= q
->queuedata
;
2511 sector_t zone
= get_zone(bmd
->bi_sector
, pd
);
2512 int used
= ((bmd
->bi_sector
- zone
) << 9) + bmd
->bi_size
;
2513 int remaining
= (pd
->settings
.size
<< 9) - used
;
2517 * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2518 * boundary, pkt_make_request() will split the bio.
2520 remaining2
= PAGE_SIZE
- bmd
->bi_size
;
2521 remaining
= max(remaining
, remaining2
);
2523 BUG_ON(remaining
< 0);
2527 static void pkt_init_queue(struct pktcdvd_device
*pd
)
2529 struct request_queue
*q
= pd
->disk
->queue
;
2531 blk_queue_make_request(q
, pkt_make_request
);
2532 blk_queue_logical_block_size(q
, CD_FRAMESIZE
);
2533 blk_queue_max_hw_sectors(q
, PACKET_MAX_SECTORS
);
2534 blk_queue_merge_bvec(q
, pkt_merge_bvec
);
2538 static int pkt_seq_show(struct seq_file
*m
, void *p
)
2540 struct pktcdvd_device
*pd
= m
->private;
2542 char bdev_buf
[BDEVNAME_SIZE
];
2543 int states
[PACKET_NUM_STATES
];
2545 seq_printf(m
, "Writer %s mapped to %s:\n", pd
->name
,
2546 bdevname(pd
->bdev
, bdev_buf
));
2548 seq_printf(m
, "\nSettings:\n");
2549 seq_printf(m
, "\tpacket size:\t\t%dkB\n", pd
->settings
.size
/ 2);
2551 if (pd
->settings
.write_type
== 0)
2555 seq_printf(m
, "\twrite type:\t\t%s\n", msg
);
2557 seq_printf(m
, "\tpacket type:\t\t%s\n", pd
->settings
.fp
? "Fixed" : "Variable");
2558 seq_printf(m
, "\tlink loss:\t\t%d\n", pd
->settings
.link_loss
);
2560 seq_printf(m
, "\ttrack mode:\t\t%d\n", pd
->settings
.track_mode
);
2562 if (pd
->settings
.block_mode
== PACKET_BLOCK_MODE1
)
2564 else if (pd
->settings
.block_mode
== PACKET_BLOCK_MODE2
)
2568 seq_printf(m
, "\tblock mode:\t\t%s\n", msg
);
2570 seq_printf(m
, "\nStatistics:\n");
2571 seq_printf(m
, "\tpackets started:\t%lu\n", pd
->stats
.pkt_started
);
2572 seq_printf(m
, "\tpackets ended:\t\t%lu\n", pd
->stats
.pkt_ended
);
2573 seq_printf(m
, "\twritten:\t\t%lukB\n", pd
->stats
.secs_w
>> 1);
2574 seq_printf(m
, "\tread gather:\t\t%lukB\n", pd
->stats
.secs_rg
>> 1);
2575 seq_printf(m
, "\tread:\t\t\t%lukB\n", pd
->stats
.secs_r
>> 1);
2577 seq_printf(m
, "\nMisc:\n");
2578 seq_printf(m
, "\treference count:\t%d\n", pd
->refcnt
);
2579 seq_printf(m
, "\tflags:\t\t\t0x%lx\n", pd
->flags
);
2580 seq_printf(m
, "\tread speed:\t\t%ukB/s\n", pd
->read_speed
);
2581 seq_printf(m
, "\twrite speed:\t\t%ukB/s\n", pd
->write_speed
);
2582 seq_printf(m
, "\tstart offset:\t\t%lu\n", pd
->offset
);
2583 seq_printf(m
, "\tmode page offset:\t%u\n", pd
->mode_offset
);
2585 seq_printf(m
, "\nQueue state:\n");
2586 seq_printf(m
, "\tbios queued:\t\t%d\n", pd
->bio_queue_size
);
2587 seq_printf(m
, "\tbios pending:\t\t%d\n", atomic_read(&pd
->cdrw
.pending_bios
));
2588 seq_printf(m
, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd
->current_sector
);
2590 pkt_count_states(pd
, states
);
2591 seq_printf(m
, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2592 states
[0], states
[1], states
[2], states
[3], states
[4], states
[5]);
2594 seq_printf(m
, "\twrite congestion marks:\toff=%d on=%d\n",
2595 pd
->write_congestion_off
,
2596 pd
->write_congestion_on
);
2600 static int pkt_seq_open(struct inode
*inode
, struct file
*file
)
2602 return single_open(file
, pkt_seq_show
, PDE_DATA(inode
));
2605 static const struct file_operations pkt_proc_fops
= {
2606 .open
= pkt_seq_open
,
2608 .llseek
= seq_lseek
,
2609 .release
= single_release
2612 static int pkt_new_dev(struct pktcdvd_device
*pd
, dev_t dev
)
2616 char b
[BDEVNAME_SIZE
];
2617 struct block_device
*bdev
;
2619 if (pd
->pkt_dev
== dev
) {
2620 pkt_err(pd
, "recursive setup not allowed\n");
2623 for (i
= 0; i
< MAX_WRITERS
; i
++) {
2624 struct pktcdvd_device
*pd2
= pkt_devs
[i
];
2627 if (pd2
->bdev
->bd_dev
== dev
) {
2628 pkt_err(pd
, "%s already setup\n",
2629 bdevname(pd2
->bdev
, b
));
2632 if (pd2
->pkt_dev
== dev
) {
2633 pkt_err(pd
, "can't chain pktcdvd devices\n");
2641 ret
= blkdev_get(bdev
, FMODE_READ
| FMODE_NDELAY
, NULL
);
2645 /* This is safe, since we have a reference from open(). */
2646 __module_get(THIS_MODULE
);
2649 set_blocksize(bdev
, CD_FRAMESIZE
);
2653 atomic_set(&pd
->cdrw
.pending_bios
, 0);
2654 pd
->cdrw
.thread
= kthread_run(kcdrwd
, pd
, "%s", pd
->name
);
2655 if (IS_ERR(pd
->cdrw
.thread
)) {
2656 pkt_err(pd
, "can't start kernel thread\n");
2661 proc_create_data(pd
->name
, 0, pkt_proc
, &pkt_proc_fops
, pd
);
2662 pkt_dbg(1, pd
, "writer mapped to %s\n", bdevname(bdev
, b
));
2666 blkdev_put(bdev
, FMODE_READ
| FMODE_NDELAY
);
2667 /* This is safe: open() is still holding a reference. */
2668 module_put(THIS_MODULE
);
2672 static int pkt_ioctl(struct block_device
*bdev
, fmode_t mode
, unsigned int cmd
, unsigned long arg
)
2674 struct pktcdvd_device
*pd
= bdev
->bd_disk
->private_data
;
2677 pkt_dbg(2, pd
, "cmd %x, dev %d:%d\n",
2678 cmd
, MAJOR(bdev
->bd_dev
), MINOR(bdev
->bd_dev
));
2680 mutex_lock(&pktcdvd_mutex
);
2684 * The door gets locked when the device is opened, so we
2685 * have to unlock it or else the eject command fails.
2687 if (pd
->refcnt
== 1)
2688 pkt_lock_door(pd
, 0);
2691 * forward selected CDROM ioctls to CD-ROM, for UDF
2693 case CDROMMULTISESSION
:
2694 case CDROMREADTOCENTRY
:
2695 case CDROM_LAST_WRITTEN
:
2696 case CDROM_SEND_PACKET
:
2697 case SCSI_IOCTL_SEND_COMMAND
:
2698 ret
= __blkdev_driver_ioctl(pd
->bdev
, mode
, cmd
, arg
);
2702 pkt_dbg(2, pd
, "Unknown ioctl (%x)\n", cmd
);
2705 mutex_unlock(&pktcdvd_mutex
);
2710 static unsigned int pkt_check_events(struct gendisk
*disk
,
2711 unsigned int clearing
)
2713 struct pktcdvd_device
*pd
= disk
->private_data
;
2714 struct gendisk
*attached_disk
;
2720 attached_disk
= pd
->bdev
->bd_disk
;
2721 if (!attached_disk
|| !attached_disk
->fops
->check_events
)
2723 return attached_disk
->fops
->check_events(attached_disk
, clearing
);
2726 static const struct block_device_operations pktcdvd_ops
= {
2727 .owner
= THIS_MODULE
,
2729 .release
= pkt_close
,
2731 .check_events
= pkt_check_events
,
2734 static char *pktcdvd_devnode(struct gendisk
*gd
, umode_t
*mode
)
2736 return kasprintf(GFP_KERNEL
, "pktcdvd/%s", gd
->disk_name
);
2740 * Set up mapping from pktcdvd device to CD-ROM device.
2742 static int pkt_setup_dev(dev_t dev
, dev_t
* pkt_dev
)
2746 struct pktcdvd_device
*pd
;
2747 struct gendisk
*disk
;
2749 mutex_lock_nested(&ctl_mutex
, SINGLE_DEPTH_NESTING
);
2751 for (idx
= 0; idx
< MAX_WRITERS
; idx
++)
2754 if (idx
== MAX_WRITERS
) {
2755 pr_err("max %d writers supported\n", MAX_WRITERS
);
2760 pd
= kzalloc(sizeof(struct pktcdvd_device
), GFP_KERNEL
);
2764 pd
->rb_pool
= mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE
,
2765 sizeof(struct pkt_rb_node
));
2769 INIT_LIST_HEAD(&pd
->cdrw
.pkt_free_list
);
2770 INIT_LIST_HEAD(&pd
->cdrw
.pkt_active_list
);
2771 spin_lock_init(&pd
->cdrw
.active_list_lock
);
2773 spin_lock_init(&pd
->lock
);
2774 spin_lock_init(&pd
->iosched
.lock
);
2775 bio_list_init(&pd
->iosched
.read_queue
);
2776 bio_list_init(&pd
->iosched
.write_queue
);
2777 sprintf(pd
->name
, DRIVER_NAME
"%d", idx
);
2778 init_waitqueue_head(&pd
->wqueue
);
2779 pd
->bio_queue
= RB_ROOT
;
2781 pd
->write_congestion_on
= write_congestion_on
;
2782 pd
->write_congestion_off
= write_congestion_off
;
2784 disk
= alloc_disk(1);
2788 disk
->major
= pktdev_major
;
2789 disk
->first_minor
= idx
;
2790 disk
->fops
= &pktcdvd_ops
;
2791 disk
->flags
= GENHD_FL_REMOVABLE
;
2792 strcpy(disk
->disk_name
, pd
->name
);
2793 disk
->devnode
= pktcdvd_devnode
;
2794 disk
->private_data
= pd
;
2795 disk
->queue
= blk_alloc_queue(GFP_KERNEL
);
2799 pd
->pkt_dev
= MKDEV(pktdev_major
, idx
);
2800 ret
= pkt_new_dev(pd
, dev
);
2804 /* inherit events of the host device */
2805 disk
->events
= pd
->bdev
->bd_disk
->events
;
2806 disk
->async_events
= pd
->bdev
->bd_disk
->async_events
;
2810 pkt_sysfs_dev_new(pd
);
2811 pkt_debugfs_dev_new(pd
);
2815 *pkt_dev
= pd
->pkt_dev
;
2817 mutex_unlock(&ctl_mutex
);
2821 blk_cleanup_queue(disk
->queue
);
2826 mempool_destroy(pd
->rb_pool
);
2829 mutex_unlock(&ctl_mutex
);
2830 pr_err("setup of pktcdvd device failed\n");
2835 * Tear down mapping from pktcdvd device to CD-ROM device.
2837 static int pkt_remove_dev(dev_t pkt_dev
)
2839 struct pktcdvd_device
*pd
;
2843 mutex_lock_nested(&ctl_mutex
, SINGLE_DEPTH_NESTING
);
2845 for (idx
= 0; idx
< MAX_WRITERS
; idx
++) {
2847 if (pd
&& (pd
->pkt_dev
== pkt_dev
))
2850 if (idx
== MAX_WRITERS
) {
2851 pr_debug("dev not setup\n");
2856 if (pd
->refcnt
> 0) {
2860 if (!IS_ERR(pd
->cdrw
.thread
))
2861 kthread_stop(pd
->cdrw
.thread
);
2863 pkt_devs
[idx
] = NULL
;
2865 pkt_debugfs_dev_remove(pd
);
2866 pkt_sysfs_dev_remove(pd
);
2868 blkdev_put(pd
->bdev
, FMODE_READ
| FMODE_NDELAY
);
2870 remove_proc_entry(pd
->name
, pkt_proc
);
2871 pkt_dbg(1, pd
, "writer unmapped\n");
2873 del_gendisk(pd
->disk
);
2874 blk_cleanup_queue(pd
->disk
->queue
);
2877 mempool_destroy(pd
->rb_pool
);
2880 /* This is safe: open() is still holding a reference. */
2881 module_put(THIS_MODULE
);
2884 mutex_unlock(&ctl_mutex
);
2888 static void pkt_get_status(struct pkt_ctrl_command
*ctrl_cmd
)
2890 struct pktcdvd_device
*pd
;
2892 mutex_lock_nested(&ctl_mutex
, SINGLE_DEPTH_NESTING
);
2894 pd
= pkt_find_dev_from_minor(ctrl_cmd
->dev_index
);
2896 ctrl_cmd
->dev
= new_encode_dev(pd
->bdev
->bd_dev
);
2897 ctrl_cmd
->pkt_dev
= new_encode_dev(pd
->pkt_dev
);
2900 ctrl_cmd
->pkt_dev
= 0;
2902 ctrl_cmd
->num_devices
= MAX_WRITERS
;
2904 mutex_unlock(&ctl_mutex
);
2907 static long pkt_ctl_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
2909 void __user
*argp
= (void __user
*)arg
;
2910 struct pkt_ctrl_command ctrl_cmd
;
2914 if (cmd
!= PACKET_CTRL_CMD
)
2917 if (copy_from_user(&ctrl_cmd
, argp
, sizeof(struct pkt_ctrl_command
)))
2920 switch (ctrl_cmd
.command
) {
2921 case PKT_CTRL_CMD_SETUP
:
2922 if (!capable(CAP_SYS_ADMIN
))
2924 ret
= pkt_setup_dev(new_decode_dev(ctrl_cmd
.dev
), &pkt_dev
);
2925 ctrl_cmd
.pkt_dev
= new_encode_dev(pkt_dev
);
2927 case PKT_CTRL_CMD_TEARDOWN
:
2928 if (!capable(CAP_SYS_ADMIN
))
2930 ret
= pkt_remove_dev(new_decode_dev(ctrl_cmd
.pkt_dev
));
2932 case PKT_CTRL_CMD_STATUS
:
2933 pkt_get_status(&ctrl_cmd
);
2939 if (copy_to_user(argp
, &ctrl_cmd
, sizeof(struct pkt_ctrl_command
)))
2944 #ifdef CONFIG_COMPAT
2945 static long pkt_ctl_compat_ioctl(struct file
*file
, unsigned int cmd
, unsigned long arg
)
2947 return pkt_ctl_ioctl(file
, cmd
, (unsigned long)compat_ptr(arg
));
2951 static const struct file_operations pkt_ctl_fops
= {
2952 .open
= nonseekable_open
,
2953 .unlocked_ioctl
= pkt_ctl_ioctl
,
2954 #ifdef CONFIG_COMPAT
2955 .compat_ioctl
= pkt_ctl_compat_ioctl
,
2957 .owner
= THIS_MODULE
,
2958 .llseek
= no_llseek
,
2961 static struct miscdevice pkt_misc
= {
2962 .minor
= MISC_DYNAMIC_MINOR
,
2963 .name
= DRIVER_NAME
,
2964 .nodename
= "pktcdvd/control",
2965 .fops
= &pkt_ctl_fops
2968 static int __init
pkt_init(void)
2972 mutex_init(&ctl_mutex
);
2974 psd_pool
= mempool_create_kmalloc_pool(PSD_POOL_SIZE
,
2975 sizeof(struct packet_stacked_data
));
2979 ret
= register_blkdev(pktdev_major
, DRIVER_NAME
);
2981 pr_err("unable to register block device\n");
2987 ret
= pkt_sysfs_init();
2993 ret
= misc_register(&pkt_misc
);
2995 pr_err("unable to register misc device\n");
2999 pkt_proc
= proc_mkdir("driver/"DRIVER_NAME
, NULL
);
3004 pkt_debugfs_cleanup();
3005 pkt_sysfs_cleanup();
3007 unregister_blkdev(pktdev_major
, DRIVER_NAME
);
3009 mempool_destroy(psd_pool
);
3013 static void __exit
pkt_exit(void)
3015 remove_proc_entry("driver/"DRIVER_NAME
, NULL
);
3016 misc_deregister(&pkt_misc
);
3018 pkt_debugfs_cleanup();
3019 pkt_sysfs_cleanup();
3021 unregister_blkdev(pktdev_major
, DRIVER_NAME
);
3022 mempool_destroy(psd_pool
);
3025 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3026 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3027 MODULE_LICENSE("GPL");
3029 module_init(pkt_init
);
3030 module_exit(pkt_exit
);