7f3d78de265c389af02d763ba0ddb0ea339404b3
[linux-3.10.git] / drivers / block / pktcdvd.c
1 /*
2  * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
3  * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
4  *
5  * May be copied or modified under the terms of the GNU General Public
6  * License.  See linux/COPYING for more information.
7  *
8  * Packet writing layer for ATAPI and SCSI CD-R, CD-RW, DVD-R, and
9  * DVD-RW devices (aka an exercise in block layer masturbation)
10  *
11  *
12  * TODO: (circa order of when I will fix it)
13  * - Only able to write on CD-RW media right now.
14  * - check host application code on media and set it in write page
15  * - interface for UDF <-> packet to negotiate a new location when a write
16  *   fails.
17  * - handle OPC, especially for -RW media
18  *
19  * Theory of operation:
20  *
21  * We use a custom make_request_fn function that forwards reads directly to
22  * the underlying CD device. Write requests are either attached directly to
23  * a live packet_data object, or simply stored sequentially in a list for
24  * later processing by the kcdrwd kernel thread. This driver doesn't use
25  * any elevator functionally as defined by the elevator_s struct, but the
26  * underlying CD device uses a standard elevator.
27  *
28  * This strategy makes it possible to do very late merging of IO requests.
29  * A new bio sent to pkt_make_request can be merged with a live packet_data
30  * object even if the object is in the data gathering state.
31  *
32  *************************************************************************/
33
34 #define VERSION_CODE    "v0.2.0a 2004-07-14 Jens Axboe (axboe@suse.de) and petero2@telia.com"
35
36 #include <linux/pktcdvd.h>
37 #include <linux/config.h>
38 #include <linux/module.h>
39 #include <linux/types.h>
40 #include <linux/kernel.h>
41 #include <linux/kthread.h>
42 #include <linux/errno.h>
43 #include <linux/spinlock.h>
44 #include <linux/file.h>
45 #include <linux/proc_fs.h>
46 #include <linux/seq_file.h>
47 #include <linux/miscdevice.h>
48 #include <linux/suspend.h>
49 #include <scsi/scsi_cmnd.h>
50 #include <scsi/scsi_ioctl.h>
51
52 #include <asm/uaccess.h>
53
54 #if PACKET_DEBUG
55 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
56 #else
57 #define DPRINTK(fmt, args...)
58 #endif
59
60 #if PACKET_DEBUG > 1
61 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
62 #else
63 #define VPRINTK(fmt, args...)
64 #endif
65
66 #define MAX_SPEED 0xffff
67
68 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
69
70 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
71 static struct proc_dir_entry *pkt_proc;
72 static int pkt_major;
73 static struct semaphore ctl_mutex;      /* Serialize open/close/setup/teardown */
74 static mempool_t *psd_pool;
75
76
77 static void pkt_bio_finished(struct pktcdvd_device *pd)
78 {
79         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
80         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
81                 VPRINTK("pktcdvd: queue empty\n");
82                 atomic_set(&pd->iosched.attention, 1);
83                 wake_up(&pd->wqueue);
84         }
85 }
86
87 static void pkt_bio_destructor(struct bio *bio)
88 {
89         kfree(bio->bi_io_vec);
90         kfree(bio);
91 }
92
93 static struct bio *pkt_bio_alloc(int nr_iovecs)
94 {
95         struct bio_vec *bvl = NULL;
96         struct bio *bio;
97
98         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
99         if (!bio)
100                 goto no_bio;
101         bio_init(bio);
102
103         bvl = kmalloc(nr_iovecs * sizeof(struct bio_vec), GFP_KERNEL);
104         if (!bvl)
105                 goto no_bvl;
106         memset(bvl, 0, nr_iovecs * sizeof(struct bio_vec));
107
108         bio->bi_max_vecs = nr_iovecs;
109         bio->bi_io_vec = bvl;
110         bio->bi_destructor = pkt_bio_destructor;
111
112         return bio;
113
114  no_bvl:
115         kfree(bio);
116  no_bio:
117         return NULL;
118 }
119
120 /*
121  * Allocate a packet_data struct
122  */
123 static struct packet_data *pkt_alloc_packet_data(void)
124 {
125         int i;
126         struct packet_data *pkt;
127
128         pkt = kmalloc(sizeof(struct packet_data), GFP_KERNEL);
129         if (!pkt)
130                 goto no_pkt;
131         memset(pkt, 0, sizeof(struct packet_data));
132
133         pkt->w_bio = pkt_bio_alloc(PACKET_MAX_SIZE);
134         if (!pkt->w_bio)
135                 goto no_bio;
136
137         for (i = 0; i < PAGES_PER_PACKET; i++) {
138                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
139                 if (!pkt->pages[i])
140                         goto no_page;
141         }
142
143         spin_lock_init(&pkt->lock);
144
145         for (i = 0; i < PACKET_MAX_SIZE; i++) {
146                 struct bio *bio = pkt_bio_alloc(1);
147                 if (!bio)
148                         goto no_rd_bio;
149                 pkt->r_bios[i] = bio;
150         }
151
152         return pkt;
153
154 no_rd_bio:
155         for (i = 0; i < PACKET_MAX_SIZE; i++) {
156                 struct bio *bio = pkt->r_bios[i];
157                 if (bio)
158                         bio_put(bio);
159         }
160
161 no_page:
162         for (i = 0; i < PAGES_PER_PACKET; i++)
163                 if (pkt->pages[i])
164                         __free_page(pkt->pages[i]);
165         bio_put(pkt->w_bio);
166 no_bio:
167         kfree(pkt);
168 no_pkt:
169         return NULL;
170 }
171
172 /*
173  * Free a packet_data struct
174  */
175 static void pkt_free_packet_data(struct packet_data *pkt)
176 {
177         int i;
178
179         for (i = 0; i < PACKET_MAX_SIZE; i++) {
180                 struct bio *bio = pkt->r_bios[i];
181                 if (bio)
182                         bio_put(bio);
183         }
184         for (i = 0; i < PAGES_PER_PACKET; i++)
185                 __free_page(pkt->pages[i]);
186         bio_put(pkt->w_bio);
187         kfree(pkt);
188 }
189
190 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
191 {
192         struct packet_data *pkt, *next;
193
194         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
195
196         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
197                 pkt_free_packet_data(pkt);
198         }
199 }
200
201 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
202 {
203         struct packet_data *pkt;
204
205         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
206         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
207         spin_lock_init(&pd->cdrw.active_list_lock);
208         while (nr_packets > 0) {
209                 pkt = pkt_alloc_packet_data();
210                 if (!pkt) {
211                         pkt_shrink_pktlist(pd);
212                         return 0;
213                 }
214                 pkt->id = nr_packets;
215                 pkt->pd = pd;
216                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
217                 nr_packets--;
218         }
219         return 1;
220 }
221
222 static void *pkt_rb_alloc(unsigned int __nocast gfp_mask, void *data)
223 {
224         return kmalloc(sizeof(struct pkt_rb_node), gfp_mask);
225 }
226
227 static void pkt_rb_free(void *ptr, void *data)
228 {
229         kfree(ptr);
230 }
231
232 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
233 {
234         struct rb_node *n = rb_next(&node->rb_node);
235         if (!n)
236                 return NULL;
237         return rb_entry(n, struct pkt_rb_node, rb_node);
238 }
239
240 static inline void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
241 {
242         rb_erase(&node->rb_node, &pd->bio_queue);
243         mempool_free(node, pd->rb_pool);
244         pd->bio_queue_size--;
245         BUG_ON(pd->bio_queue_size < 0);
246 }
247
248 /*
249  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
250  */
251 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
252 {
253         struct rb_node *n = pd->bio_queue.rb_node;
254         struct rb_node *next;
255         struct pkt_rb_node *tmp;
256
257         if (!n) {
258                 BUG_ON(pd->bio_queue_size > 0);
259                 return NULL;
260         }
261
262         for (;;) {
263                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
264                 if (s <= tmp->bio->bi_sector)
265                         next = n->rb_left;
266                 else
267                         next = n->rb_right;
268                 if (!next)
269                         break;
270                 n = next;
271         }
272
273         if (s > tmp->bio->bi_sector) {
274                 tmp = pkt_rbtree_next(tmp);
275                 if (!tmp)
276                         return NULL;
277         }
278         BUG_ON(s > tmp->bio->bi_sector);
279         return tmp;
280 }
281
282 /*
283  * Insert a node into the pd->bio_queue rb tree.
284  */
285 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
286 {
287         struct rb_node **p = &pd->bio_queue.rb_node;
288         struct rb_node *parent = NULL;
289         sector_t s = node->bio->bi_sector;
290         struct pkt_rb_node *tmp;
291
292         while (*p) {
293                 parent = *p;
294                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
295                 if (s < tmp->bio->bi_sector)
296                         p = &(*p)->rb_left;
297                 else
298                         p = &(*p)->rb_right;
299         }
300         rb_link_node(&node->rb_node, parent, p);
301         rb_insert_color(&node->rb_node, &pd->bio_queue);
302         pd->bio_queue_size++;
303 }
304
305 /*
306  * Add a bio to a single linked list defined by its head and tail pointers.
307  */
308 static inline void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
309 {
310         bio->bi_next = NULL;
311         if (*list_tail) {
312                 BUG_ON((*list_head) == NULL);
313                 (*list_tail)->bi_next = bio;
314                 (*list_tail) = bio;
315         } else {
316                 BUG_ON((*list_head) != NULL);
317                 (*list_head) = bio;
318                 (*list_tail) = bio;
319         }
320 }
321
322 /*
323  * Remove and return the first bio from a single linked list defined by its
324  * head and tail pointers.
325  */
326 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
327 {
328         struct bio *bio;
329
330         if (*list_head == NULL)
331                 return NULL;
332
333         bio = *list_head;
334         *list_head = bio->bi_next;
335         if (*list_head == NULL)
336                 *list_tail = NULL;
337
338         bio->bi_next = NULL;
339         return bio;
340 }
341
342 /*
343  * Send a packet_command to the underlying block device and
344  * wait for completion.
345  */
346 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
347 {
348         char sense[SCSI_SENSE_BUFFERSIZE];
349         request_queue_t *q;
350         struct request *rq;
351         DECLARE_COMPLETION(wait);
352         int err = 0;
353
354         q = bdev_get_queue(pd->bdev);
355
356         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ? WRITE : READ,
357                              __GFP_WAIT);
358         rq->errors = 0;
359         rq->rq_disk = pd->bdev->bd_disk;
360         rq->bio = NULL;
361         rq->buffer = NULL;
362         rq->timeout = 60*HZ;
363         rq->data = cgc->buffer;
364         rq->data_len = cgc->buflen;
365         rq->sense = sense;
366         memset(sense, 0, sizeof(sense));
367         rq->sense_len = 0;
368         rq->flags |= REQ_BLOCK_PC | REQ_HARDBARRIER;
369         if (cgc->quiet)
370                 rq->flags |= REQ_QUIET;
371         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
372         if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
373                 memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);
374
375         rq->ref_count++;
376         rq->flags |= REQ_NOMERGE;
377         rq->waiting = &wait;
378         rq->end_io = blk_end_sync_rq;
379         elv_add_request(q, rq, ELEVATOR_INSERT_BACK, 1);
380         generic_unplug_device(q);
381         wait_for_completion(&wait);
382
383         if (rq->errors)
384                 err = -EIO;
385
386         blk_put_request(rq);
387         return err;
388 }
389
390 /*
391  * A generic sense dump / resolve mechanism should be implemented across
392  * all ATAPI + SCSI devices.
393  */
394 static void pkt_dump_sense(struct packet_command *cgc)
395 {
396         static char *info[9] = { "No sense", "Recovered error", "Not ready",
397                                  "Medium error", "Hardware error", "Illegal request",
398                                  "Unit attention", "Data protect", "Blank check" };
399         int i;
400         struct request_sense *sense = cgc->sense;
401
402         printk("pktcdvd:");
403         for (i = 0; i < CDROM_PACKET_SIZE; i++)
404                 printk(" %02x", cgc->cmd[i]);
405         printk(" - ");
406
407         if (sense == NULL) {
408                 printk("no sense\n");
409                 return;
410         }
411
412         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
413
414         if (sense->sense_key > 8) {
415                 printk(" (INVALID)\n");
416                 return;
417         }
418
419         printk(" (%s)\n", info[sense->sense_key]);
420 }
421
422 /*
423  * flush the drive cache to media
424  */
425 static int pkt_flush_cache(struct pktcdvd_device *pd)
426 {
427         struct packet_command cgc;
428
429         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
430         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
431         cgc.quiet = 1;
432
433         /*
434          * the IMMED bit -- we default to not setting it, although that
435          * would allow a much faster close, this is safer
436          */
437 #if 0
438         cgc.cmd[1] = 1 << 1;
439 #endif
440         return pkt_generic_packet(pd, &cgc);
441 }
442
443 /*
444  * speed is given as the normal factor, e.g. 4 for 4x
445  */
446 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
447 {
448         struct packet_command cgc;
449         struct request_sense sense;
450         int ret;
451
452         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
453         cgc.sense = &sense;
454         cgc.cmd[0] = GPCMD_SET_SPEED;
455         cgc.cmd[2] = (read_speed >> 8) & 0xff;
456         cgc.cmd[3] = read_speed & 0xff;
457         cgc.cmd[4] = (write_speed >> 8) & 0xff;
458         cgc.cmd[5] = write_speed & 0xff;
459
460         if ((ret = pkt_generic_packet(pd, &cgc)))
461                 pkt_dump_sense(&cgc);
462
463         return ret;
464 }
465
466 /*
467  * Queue a bio for processing by the low-level CD device. Must be called
468  * from process context.
469  */
470 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
471 {
472         spin_lock(&pd->iosched.lock);
473         if (bio_data_dir(bio) == READ) {
474                 pkt_add_list_last(bio, &pd->iosched.read_queue,
475                                   &pd->iosched.read_queue_tail);
476         } else {
477                 pkt_add_list_last(bio, &pd->iosched.write_queue,
478                                   &pd->iosched.write_queue_tail);
479         }
480         spin_unlock(&pd->iosched.lock);
481
482         atomic_set(&pd->iosched.attention, 1);
483         wake_up(&pd->wqueue);
484 }
485
486 /*
487  * Process the queued read/write requests. This function handles special
488  * requirements for CDRW drives:
489  * - A cache flush command must be inserted before a read request if the
490  *   previous request was a write.
491  * - Switching between reading and writing is slow, so don't do it more often
492  *   than necessary.
493  * - Optimize for throughput at the expense of latency. This means that streaming
494  *   writes will never be interrupted by a read, but if the drive has to seek
495  *   before the next write, switch to reading instead if there are any pending
496  *   read requests.
497  * - Set the read speed according to current usage pattern. When only reading
498  *   from the device, it's best to use the highest possible read speed, but
499  *   when switching often between reading and writing, it's better to have the
500  *   same read and write speeds.
501  */
502 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
503 {
504         request_queue_t *q;
505
506         if (atomic_read(&pd->iosched.attention) == 0)
507                 return;
508         atomic_set(&pd->iosched.attention, 0);
509
510         q = bdev_get_queue(pd->bdev);
511
512         for (;;) {
513                 struct bio *bio;
514                 int reads_queued, writes_queued;
515
516                 spin_lock(&pd->iosched.lock);
517                 reads_queued = (pd->iosched.read_queue != NULL);
518                 writes_queued = (pd->iosched.write_queue != NULL);
519                 spin_unlock(&pd->iosched.lock);
520
521                 if (!reads_queued && !writes_queued)
522                         break;
523
524                 if (pd->iosched.writing) {
525                         int need_write_seek = 1;
526                         spin_lock(&pd->iosched.lock);
527                         bio = pd->iosched.write_queue;
528                         spin_unlock(&pd->iosched.lock);
529                         if (bio && (bio->bi_sector == pd->iosched.last_write))
530                                 need_write_seek = 0;
531                         if (need_write_seek && reads_queued) {
532                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
533                                         VPRINTK("pktcdvd: write, waiting\n");
534                                         break;
535                                 }
536                                 pkt_flush_cache(pd);
537                                 pd->iosched.writing = 0;
538                         }
539                 } else {
540                         if (!reads_queued && writes_queued) {
541                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
542                                         VPRINTK("pktcdvd: read, waiting\n");
543                                         break;
544                                 }
545                                 pd->iosched.writing = 1;
546                         }
547                 }
548
549                 spin_lock(&pd->iosched.lock);
550                 if (pd->iosched.writing) {
551                         bio = pkt_get_list_first(&pd->iosched.write_queue,
552                                                  &pd->iosched.write_queue_tail);
553                 } else {
554                         bio = pkt_get_list_first(&pd->iosched.read_queue,
555                                                  &pd->iosched.read_queue_tail);
556                 }
557                 spin_unlock(&pd->iosched.lock);
558
559                 if (!bio)
560                         continue;
561
562                 if (bio_data_dir(bio) == READ)
563                         pd->iosched.successive_reads += bio->bi_size >> 10;
564                 else {
565                         pd->iosched.successive_reads = 0;
566                         pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
567                 }
568                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
569                         if (pd->read_speed == pd->write_speed) {
570                                 pd->read_speed = MAX_SPEED;
571                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
572                         }
573                 } else {
574                         if (pd->read_speed != pd->write_speed) {
575                                 pd->read_speed = pd->write_speed;
576                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
577                         }
578                 }
579
580                 atomic_inc(&pd->cdrw.pending_bios);
581                 generic_make_request(bio);
582         }
583 }
584
585 /*
586  * Special care is needed if the underlying block device has a small
587  * max_phys_segments value.
588  */
589 static int pkt_set_segment_merging(struct pktcdvd_device *pd, request_queue_t *q)
590 {
591         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
592                 /*
593                  * The cdrom device can handle one segment/frame
594                  */
595                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
596                 return 0;
597         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
598                 /*
599                  * We can handle this case at the expense of some extra memory
600                  * copies during write operations
601                  */
602                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
603                 return 0;
604         } else {
605                 printk("pktcdvd: cdrom max_phys_segments too small\n");
606                 return -EIO;
607         }
608 }
609
610 /*
611  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
612  */
613 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
614 {
615         unsigned int copy_size = CD_FRAMESIZE;
616
617         while (copy_size > 0) {
618                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
619                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
620                         src_bvl->bv_offset + offs;
621                 void *vto = page_address(dst_page) + dst_offs;
622                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
623
624                 BUG_ON(len < 0);
625                 memcpy(vto, vfrom, len);
626                 kunmap_atomic(vfrom, KM_USER0);
627
628                 seg++;
629                 offs = 0;
630                 dst_offs += len;
631                 copy_size -= len;
632         }
633 }
634
635 /*
636  * Copy all data for this packet to pkt->pages[], so that
637  * a) The number of required segments for the write bio is minimized, which
638  *    is necessary for some scsi controllers.
639  * b) The data can be used as cache to avoid read requests if we receive a
640  *    new write request for the same zone.
641  */
642 static void pkt_make_local_copy(struct packet_data *pkt, struct page **pages, int *offsets)
643 {
644         int f, p, offs;
645
646         /* Copy all data to pkt->pages[] */
647         p = 0;
648         offs = 0;
649         for (f = 0; f < pkt->frames; f++) {
650                 if (pages[f] != pkt->pages[p]) {
651                         void *vfrom = kmap_atomic(pages[f], KM_USER0) + offsets[f];
652                         void *vto = page_address(pkt->pages[p]) + offs;
653                         memcpy(vto, vfrom, CD_FRAMESIZE);
654                         kunmap_atomic(vfrom, KM_USER0);
655                         pages[f] = pkt->pages[p];
656                         offsets[f] = offs;
657                 } else {
658                         BUG_ON(offsets[f] != offs);
659                 }
660                 offs += CD_FRAMESIZE;
661                 if (offs >= PAGE_SIZE) {
662                         BUG_ON(offs > PAGE_SIZE);
663                         offs = 0;
664                         p++;
665                 }
666         }
667 }
668
669 static int pkt_end_io_read(struct bio *bio, unsigned int bytes_done, int err)
670 {
671         struct packet_data *pkt = bio->bi_private;
672         struct pktcdvd_device *pd = pkt->pd;
673         BUG_ON(!pd);
674
675         if (bio->bi_size)
676                 return 1;
677
678         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
679                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
680
681         if (err)
682                 atomic_inc(&pkt->io_errors);
683         if (atomic_dec_and_test(&pkt->io_wait)) {
684                 atomic_inc(&pkt->run_sm);
685                 wake_up(&pd->wqueue);
686         }
687         pkt_bio_finished(pd);
688
689         return 0;
690 }
691
692 static int pkt_end_io_packet_write(struct bio *bio, unsigned int bytes_done, int err)
693 {
694         struct packet_data *pkt = bio->bi_private;
695         struct pktcdvd_device *pd = pkt->pd;
696         BUG_ON(!pd);
697
698         if (bio->bi_size)
699                 return 1;
700
701         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
702
703         pd->stats.pkt_ended++;
704
705         pkt_bio_finished(pd);
706         atomic_dec(&pkt->io_wait);
707         atomic_inc(&pkt->run_sm);
708         wake_up(&pd->wqueue);
709         return 0;
710 }
711
712 /*
713  * Schedule reads for the holes in a packet
714  */
715 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
716 {
717         int frames_read = 0;
718         struct bio *bio;
719         int f;
720         char written[PACKET_MAX_SIZE];
721
722         BUG_ON(!pkt->orig_bios);
723
724         atomic_set(&pkt->io_wait, 0);
725         atomic_set(&pkt->io_errors, 0);
726
727         if (pkt->cache_valid) {
728                 VPRINTK("pkt_gather_data: zone %llx cached\n",
729                         (unsigned long long)pkt->sector);
730                 goto out_account;
731         }
732
733         /*
734          * Figure out which frames we need to read before we can write.
735          */
736         memset(written, 0, sizeof(written));
737         spin_lock(&pkt->lock);
738         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
739                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
740                 int num_frames = bio->bi_size / CD_FRAMESIZE;
741                 BUG_ON(first_frame < 0);
742                 BUG_ON(first_frame + num_frames > pkt->frames);
743                 for (f = first_frame; f < first_frame + num_frames; f++)
744                         written[f] = 1;
745         }
746         spin_unlock(&pkt->lock);
747
748         /*
749          * Schedule reads for missing parts of the packet.
750          */
751         for (f = 0; f < pkt->frames; f++) {
752                 int p, offset;
753                 if (written[f])
754                         continue;
755                 bio = pkt->r_bios[f];
756                 bio_init(bio);
757                 bio->bi_max_vecs = 1;
758                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
759                 bio->bi_bdev = pd->bdev;
760                 bio->bi_end_io = pkt_end_io_read;
761                 bio->bi_private = pkt;
762
763                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
764                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
765                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
766                         f, pkt->pages[p], offset);
767                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
768                         BUG();
769
770                 atomic_inc(&pkt->io_wait);
771                 bio->bi_rw = READ;
772                 pkt_queue_bio(pd, bio);
773                 frames_read++;
774         }
775
776 out_account:
777         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
778                 frames_read, (unsigned long long)pkt->sector);
779         pd->stats.pkt_started++;
780         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
781         pd->stats.secs_w += pd->settings.size;
782 }
783
784 /*
785  * Find a packet matching zone, or the least recently used packet if
786  * there is no match.
787  */
788 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
789 {
790         struct packet_data *pkt;
791
792         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
793                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
794                         list_del_init(&pkt->list);
795                         if (pkt->sector != zone)
796                                 pkt->cache_valid = 0;
797                         break;
798                 }
799         }
800         return pkt;
801 }
802
803 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
804 {
805         if (pkt->cache_valid) {
806                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
807         } else {
808                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
809         }
810 }
811
812 /*
813  * recover a failed write, query for relocation if possible
814  *
815  * returns 1 if recovery is possible, or 0 if not
816  *
817  */
818 static int pkt_start_recovery(struct packet_data *pkt)
819 {
820         /*
821          * FIXME. We need help from the file system to implement
822          * recovery handling.
823          */
824         return 0;
825 #if 0
826         struct request *rq = pkt->rq;
827         struct pktcdvd_device *pd = rq->rq_disk->private_data;
828         struct block_device *pkt_bdev;
829         struct super_block *sb = NULL;
830         unsigned long old_block, new_block;
831         sector_t new_sector;
832
833         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
834         if (pkt_bdev) {
835                 sb = get_super(pkt_bdev);
836                 bdput(pkt_bdev);
837         }
838
839         if (!sb)
840                 return 0;
841
842         if (!sb->s_op || !sb->s_op->relocate_blocks)
843                 goto out;
844
845         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
846         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
847                 goto out;
848
849         new_sector = new_block * (CD_FRAMESIZE >> 9);
850         pkt->sector = new_sector;
851
852         pkt->bio->bi_sector = new_sector;
853         pkt->bio->bi_next = NULL;
854         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
855         pkt->bio->bi_idx = 0;
856
857         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
858         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
859         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
860         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
861         BUG_ON(pkt->bio->bi_private != pkt);
862
863         drop_super(sb);
864         return 1;
865
866 out:
867         drop_super(sb);
868         return 0;
869 #endif
870 }
871
872 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
873 {
874 #if PACKET_DEBUG > 1
875         static const char *state_name[] = {
876                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
877         };
878         enum packet_data_state old_state = pkt->state;
879         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
880                 state_name[old_state], state_name[state]);
881 #endif
882         pkt->state = state;
883 }
884
885 /*
886  * Scan the work queue to see if we can start a new packet.
887  * returns non-zero if any work was done.
888  */
889 static int pkt_handle_queue(struct pktcdvd_device *pd)
890 {
891         struct packet_data *pkt, *p;
892         struct bio *bio = NULL;
893         sector_t zone = 0; /* Suppress gcc warning */
894         struct pkt_rb_node *node, *first_node;
895         struct rb_node *n;
896
897         VPRINTK("handle_queue\n");
898
899         atomic_set(&pd->scan_queue, 0);
900
901         if (list_empty(&pd->cdrw.pkt_free_list)) {
902                 VPRINTK("handle_queue: no pkt\n");
903                 return 0;
904         }
905
906         /*
907          * Try to find a zone we are not already working on.
908          */
909         spin_lock(&pd->lock);
910         first_node = pkt_rbtree_find(pd, pd->current_sector);
911         if (!first_node) {
912                 n = rb_first(&pd->bio_queue);
913                 if (n)
914                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
915         }
916         node = first_node;
917         while (node) {
918                 bio = node->bio;
919                 zone = ZONE(bio->bi_sector, pd);
920                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
921                         if (p->sector == zone) {
922                                 bio = NULL;
923                                 goto try_next_bio;
924                         }
925                 }
926                 break;
927 try_next_bio:
928                 node = pkt_rbtree_next(node);
929                 if (!node) {
930                         n = rb_first(&pd->bio_queue);
931                         if (n)
932                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
933                 }
934                 if (node == first_node)
935                         node = NULL;
936         }
937         spin_unlock(&pd->lock);
938         if (!bio) {
939                 VPRINTK("handle_queue: no bio\n");
940                 return 0;
941         }
942
943         pkt = pkt_get_packet_data(pd, zone);
944         BUG_ON(!pkt);
945
946         pd->current_sector = zone + pd->settings.size;
947         pkt->sector = zone;
948         pkt->frames = pd->settings.size >> 2;
949         BUG_ON(pkt->frames > PACKET_MAX_SIZE);
950         pkt->write_size = 0;
951
952         /*
953          * Scan work queue for bios in the same zone and link them
954          * to this packet.
955          */
956         spin_lock(&pd->lock);
957         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
958         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
959                 bio = node->bio;
960                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
961                         (unsigned long long)ZONE(bio->bi_sector, pd));
962                 if (ZONE(bio->bi_sector, pd) != zone)
963                         break;
964                 pkt_rbtree_erase(pd, node);
965                 spin_lock(&pkt->lock);
966                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
967                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
968                 spin_unlock(&pkt->lock);
969         }
970         spin_unlock(&pd->lock);
971
972         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
973         pkt_set_state(pkt, PACKET_WAITING_STATE);
974         atomic_set(&pkt->run_sm, 1);
975
976         spin_lock(&pd->cdrw.active_list_lock);
977         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
978         spin_unlock(&pd->cdrw.active_list_lock);
979
980         return 1;
981 }
982
983 /*
984  * Assemble a bio to write one packet and queue the bio for processing
985  * by the underlying block device.
986  */
987 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
988 {
989         struct bio *bio;
990         struct page *pages[PACKET_MAX_SIZE];
991         int offsets[PACKET_MAX_SIZE];
992         int f;
993         int frames_write;
994
995         for (f = 0; f < pkt->frames; f++) {
996                 pages[f] = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
997                 offsets[f] = (f * CD_FRAMESIZE) % PAGE_SIZE;
998         }
999
1000         /*
1001          * Fill-in pages[] and offsets[] with data from orig_bios.
1002          */
1003         frames_write = 0;
1004         spin_lock(&pkt->lock);
1005         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1006                 int segment = bio->bi_idx;
1007                 int src_offs = 0;
1008                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1009                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1010                 BUG_ON(first_frame < 0);
1011                 BUG_ON(first_frame + num_frames > pkt->frames);
1012                 for (f = first_frame; f < first_frame + num_frames; f++) {
1013                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1014
1015                         while (src_offs >= src_bvl->bv_len) {
1016                                 src_offs -= src_bvl->bv_len;
1017                                 segment++;
1018                                 BUG_ON(segment >= bio->bi_vcnt);
1019                                 src_bvl = bio_iovec_idx(bio, segment);
1020                         }
1021
1022                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1023                                 pages[f] = src_bvl->bv_page;
1024                                 offsets[f] = src_bvl->bv_offset + src_offs;
1025                         } else {
1026                                 pkt_copy_bio_data(bio, segment, src_offs,
1027                                                   pages[f], offsets[f]);
1028                         }
1029                         src_offs += CD_FRAMESIZE;
1030                         frames_write++;
1031                 }
1032         }
1033         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1034         spin_unlock(&pkt->lock);
1035
1036         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1037                 frames_write, (unsigned long long)pkt->sector);
1038         BUG_ON(frames_write != pkt->write_size);
1039
1040         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1041                 pkt_make_local_copy(pkt, pages, offsets);
1042                 pkt->cache_valid = 1;
1043         } else {
1044                 pkt->cache_valid = 0;
1045         }
1046
1047         /* Start the write request */
1048         bio_init(pkt->w_bio);
1049         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1050         pkt->w_bio->bi_sector = pkt->sector;
1051         pkt->w_bio->bi_bdev = pd->bdev;
1052         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1053         pkt->w_bio->bi_private = pkt;
1054         for (f = 0; f < pkt->frames; f++) {
1055                 if ((f + 1 < pkt->frames) && (pages[f + 1] == pages[f]) &&
1056                     (offsets[f + 1] = offsets[f] + CD_FRAMESIZE)) {
1057                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE * 2, offsets[f]))
1058                                 BUG();
1059                         f++;
1060                 } else {
1061                         if (!bio_add_page(pkt->w_bio, pages[f], CD_FRAMESIZE, offsets[f]))
1062                                 BUG();
1063                 }
1064         }
1065         VPRINTK("pktcdvd: vcnt=%d\n", pkt->w_bio->bi_vcnt);
1066
1067         atomic_set(&pkt->io_wait, 1);
1068         pkt->w_bio->bi_rw = WRITE;
1069         pkt_queue_bio(pd, pkt->w_bio);
1070 }
1071
1072 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1073 {
1074         struct bio *bio, *next;
1075
1076         if (!uptodate)
1077                 pkt->cache_valid = 0;
1078
1079         /* Finish all bios corresponding to this packet */
1080         bio = pkt->orig_bios;
1081         while (bio) {
1082                 next = bio->bi_next;
1083                 bio->bi_next = NULL;
1084                 bio_endio(bio, bio->bi_size, uptodate ? 0 : -EIO);
1085                 bio = next;
1086         }
1087         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1088 }
1089
1090 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1091 {
1092         int uptodate;
1093
1094         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1095
1096         for (;;) {
1097                 switch (pkt->state) {
1098                 case PACKET_WAITING_STATE:
1099                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1100                                 return;
1101
1102                         pkt->sleep_time = 0;
1103                         pkt_gather_data(pd, pkt);
1104                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1105                         break;
1106
1107                 case PACKET_READ_WAIT_STATE:
1108                         if (atomic_read(&pkt->io_wait) > 0)
1109                                 return;
1110
1111                         if (atomic_read(&pkt->io_errors) > 0) {
1112                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1113                         } else {
1114                                 pkt_start_write(pd, pkt);
1115                         }
1116                         break;
1117
1118                 case PACKET_WRITE_WAIT_STATE:
1119                         if (atomic_read(&pkt->io_wait) > 0)
1120                                 return;
1121
1122                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1123                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1124                         } else {
1125                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1126                         }
1127                         break;
1128
1129                 case PACKET_RECOVERY_STATE:
1130                         if (pkt_start_recovery(pkt)) {
1131                                 pkt_start_write(pd, pkt);
1132                         } else {
1133                                 VPRINTK("No recovery possible\n");
1134                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1135                         }
1136                         break;
1137
1138                 case PACKET_FINISHED_STATE:
1139                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1140                         pkt_finish_packet(pkt, uptodate);
1141                         return;
1142
1143                 default:
1144                         BUG();
1145                         break;
1146                 }
1147         }
1148 }
1149
1150 static void pkt_handle_packets(struct pktcdvd_device *pd)
1151 {
1152         struct packet_data *pkt, *next;
1153
1154         VPRINTK("pkt_handle_packets\n");
1155
1156         /*
1157          * Run state machine for active packets
1158          */
1159         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1160                 if (atomic_read(&pkt->run_sm) > 0) {
1161                         atomic_set(&pkt->run_sm, 0);
1162                         pkt_run_state_machine(pd, pkt);
1163                 }
1164         }
1165
1166         /*
1167          * Move no longer active packets to the free list
1168          */
1169         spin_lock(&pd->cdrw.active_list_lock);
1170         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1171                 if (pkt->state == PACKET_FINISHED_STATE) {
1172                         list_del(&pkt->list);
1173                         pkt_put_packet_data(pd, pkt);
1174                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1175                         atomic_set(&pd->scan_queue, 1);
1176                 }
1177         }
1178         spin_unlock(&pd->cdrw.active_list_lock);
1179 }
1180
1181 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1182 {
1183         struct packet_data *pkt;
1184         int i;
1185
1186         for (i = 0; i <= PACKET_NUM_STATES; i++)
1187                 states[i] = 0;
1188
1189         spin_lock(&pd->cdrw.active_list_lock);
1190         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1191                 states[pkt->state]++;
1192         }
1193         spin_unlock(&pd->cdrw.active_list_lock);
1194 }
1195
1196 /*
1197  * kcdrwd is woken up when writes have been queued for one of our
1198  * registered devices
1199  */
1200 static int kcdrwd(void *foobar)
1201 {
1202         struct pktcdvd_device *pd = foobar;
1203         struct packet_data *pkt;
1204         long min_sleep_time, residue;
1205
1206         set_user_nice(current, -20);
1207
1208         for (;;) {
1209                 DECLARE_WAITQUEUE(wait, current);
1210
1211                 /*
1212                  * Wait until there is something to do
1213                  */
1214                 add_wait_queue(&pd->wqueue, &wait);
1215                 for (;;) {
1216                         set_current_state(TASK_INTERRUPTIBLE);
1217
1218                         /* Check if we need to run pkt_handle_queue */
1219                         if (atomic_read(&pd->scan_queue) > 0)
1220                                 goto work_to_do;
1221
1222                         /* Check if we need to run the state machine for some packet */
1223                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1224                                 if (atomic_read(&pkt->run_sm) > 0)
1225                                         goto work_to_do;
1226                         }
1227
1228                         /* Check if we need to process the iosched queues */
1229                         if (atomic_read(&pd->iosched.attention) != 0)
1230                                 goto work_to_do;
1231
1232                         /* Otherwise, go to sleep */
1233                         if (PACKET_DEBUG > 1) {
1234                                 int states[PACKET_NUM_STATES];
1235                                 pkt_count_states(pd, states);
1236                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1237                                         states[0], states[1], states[2], states[3],
1238                                         states[4], states[5]);
1239                         }
1240
1241                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1242                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1243                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1244                                         min_sleep_time = pkt->sleep_time;
1245                         }
1246
1247                         generic_unplug_device(bdev_get_queue(pd->bdev));
1248
1249                         VPRINTK("kcdrwd: sleeping\n");
1250                         residue = schedule_timeout(min_sleep_time);
1251                         VPRINTK("kcdrwd: wake up\n");
1252
1253                         /* make swsusp happy with our thread */
1254                         if (current->flags & PF_FREEZE)
1255                                 refrigerator(PF_FREEZE);
1256
1257                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1258                                 if (!pkt->sleep_time)
1259                                         continue;
1260                                 pkt->sleep_time -= min_sleep_time - residue;
1261                                 if (pkt->sleep_time <= 0) {
1262                                         pkt->sleep_time = 0;
1263                                         atomic_inc(&pkt->run_sm);
1264                                 }
1265                         }
1266
1267                         if (signal_pending(current)) {
1268                                 flush_signals(current);
1269                         }
1270                         if (kthread_should_stop())
1271                                 break;
1272                 }
1273 work_to_do:
1274                 set_current_state(TASK_RUNNING);
1275                 remove_wait_queue(&pd->wqueue, &wait);
1276
1277                 if (kthread_should_stop())
1278                         break;
1279
1280                 /*
1281                  * if pkt_handle_queue returns true, we can queue
1282                  * another request.
1283                  */
1284                 while (pkt_handle_queue(pd))
1285                         ;
1286
1287                 /*
1288                  * Handle packet state machine
1289                  */
1290                 pkt_handle_packets(pd);
1291
1292                 /*
1293                  * Handle iosched queues
1294                  */
1295                 pkt_iosched_process_queue(pd);
1296         }
1297
1298         return 0;
1299 }
1300
1301 static void pkt_print_settings(struct pktcdvd_device *pd)
1302 {
1303         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1304         printk("%u blocks, ", pd->settings.size >> 2);
1305         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1306 }
1307
1308 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1309 {
1310         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1311
1312         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1313         cgc->cmd[2] = page_code | (page_control << 6);
1314         cgc->cmd[7] = cgc->buflen >> 8;
1315         cgc->cmd[8] = cgc->buflen & 0xff;
1316         cgc->data_direction = CGC_DATA_READ;
1317         return pkt_generic_packet(pd, cgc);
1318 }
1319
1320 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1321 {
1322         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1323         memset(cgc->buffer, 0, 2);
1324         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1325         cgc->cmd[1] = 0x10;             /* PF */
1326         cgc->cmd[7] = cgc->buflen >> 8;
1327         cgc->cmd[8] = cgc->buflen & 0xff;
1328         cgc->data_direction = CGC_DATA_WRITE;
1329         return pkt_generic_packet(pd, cgc);
1330 }
1331
1332 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1333 {
1334         struct packet_command cgc;
1335         int ret;
1336
1337         /* set up command and get the disc info */
1338         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1339         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1340         cgc.cmd[8] = cgc.buflen = 2;
1341         cgc.quiet = 1;
1342
1343         if ((ret = pkt_generic_packet(pd, &cgc)))
1344                 return ret;
1345
1346         /* not all drives have the same disc_info length, so requeue
1347          * packet with the length the drive tells us it can supply
1348          */
1349         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1350                      sizeof(di->disc_information_length);
1351
1352         if (cgc.buflen > sizeof(disc_information))
1353                 cgc.buflen = sizeof(disc_information);
1354
1355         cgc.cmd[8] = cgc.buflen;
1356         return pkt_generic_packet(pd, &cgc);
1357 }
1358
1359 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1360 {
1361         struct packet_command cgc;
1362         int ret;
1363
1364         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1365         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1366         cgc.cmd[1] = type & 3;
1367         cgc.cmd[4] = (track & 0xff00) >> 8;
1368         cgc.cmd[5] = track & 0xff;
1369         cgc.cmd[8] = 8;
1370         cgc.quiet = 1;
1371
1372         if ((ret = pkt_generic_packet(pd, &cgc)))
1373                 return ret;
1374
1375         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1376                      sizeof(ti->track_information_length);
1377
1378         if (cgc.buflen > sizeof(track_information))
1379                 cgc.buflen = sizeof(track_information);
1380
1381         cgc.cmd[8] = cgc.buflen;
1382         return pkt_generic_packet(pd, &cgc);
1383 }
1384
1385 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1386 {
1387         disc_information di;
1388         track_information ti;
1389         __u32 last_track;
1390         int ret = -1;
1391
1392         if ((ret = pkt_get_disc_info(pd, &di)))
1393                 return ret;
1394
1395         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1396         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1397                 return ret;
1398
1399         /* if this track is blank, try the previous. */
1400         if (ti.blank) {
1401                 last_track--;
1402                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1403                         return ret;
1404         }
1405
1406         /* if last recorded field is valid, return it. */
1407         if (ti.lra_v) {
1408                 *last_written = be32_to_cpu(ti.last_rec_address);
1409         } else {
1410                 /* make it up instead */
1411                 *last_written = be32_to_cpu(ti.track_start) +
1412                                 be32_to_cpu(ti.track_size);
1413                 if (ti.free_blocks)
1414                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1415         }
1416         return 0;
1417 }
1418
1419 /*
1420  * write mode select package based on pd->settings
1421  */
1422 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1423 {
1424         struct packet_command cgc;
1425         struct request_sense sense;
1426         write_param_page *wp;
1427         char buffer[128];
1428         int ret, size;
1429
1430         /* doesn't apply to DVD+RW or DVD-RAM */
1431         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1432                 return 0;
1433
1434         memset(buffer, 0, sizeof(buffer));
1435         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1436         cgc.sense = &sense;
1437         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1438                 pkt_dump_sense(&cgc);
1439                 return ret;
1440         }
1441
1442         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1443         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1444         if (size > sizeof(buffer))
1445                 size = sizeof(buffer);
1446
1447         /*
1448          * now get it all
1449          */
1450         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1451         cgc.sense = &sense;
1452         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1453                 pkt_dump_sense(&cgc);
1454                 return ret;
1455         }
1456
1457         /*
1458          * write page is offset header + block descriptor length
1459          */
1460         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1461
1462         wp->fp = pd->settings.fp;
1463         wp->track_mode = pd->settings.track_mode;
1464         wp->write_type = pd->settings.write_type;
1465         wp->data_block_type = pd->settings.block_mode;
1466
1467         wp->multi_session = 0;
1468
1469 #ifdef PACKET_USE_LS
1470         wp->link_size = 7;
1471         wp->ls_v = 1;
1472 #endif
1473
1474         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1475                 wp->session_format = 0;
1476                 wp->subhdr2 = 0x20;
1477         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1478                 wp->session_format = 0x20;
1479                 wp->subhdr2 = 8;
1480 #if 0
1481                 wp->mcn[0] = 0x80;
1482                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1483 #endif
1484         } else {
1485                 /*
1486                  * paranoia
1487                  */
1488                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1489                 return 1;
1490         }
1491         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1492
1493         cgc.buflen = cgc.cmd[8] = size;
1494         if ((ret = pkt_mode_select(pd, &cgc))) {
1495                 pkt_dump_sense(&cgc);
1496                 return ret;
1497         }
1498
1499         pkt_print_settings(pd);
1500         return 0;
1501 }
1502
1503 /*
1504  * 0 -- we can write to this track, 1 -- we can't
1505  */
1506 static int pkt_good_track(track_information *ti)
1507 {
1508         /*
1509          * only good for CD-RW at the moment, not DVD-RW
1510          */
1511
1512         /*
1513          * FIXME: only for FP
1514          */
1515         if (ti->fp == 0)
1516                 return 0;
1517
1518         /*
1519          * "good" settings as per Mt Fuji.
1520          */
1521         if (ti->rt == 0 && ti->blank == 0 && ti->packet == 1)
1522                 return 0;
1523
1524         if (ti->rt == 0 && ti->blank == 1 && ti->packet == 1)
1525                 return 0;
1526
1527         if (ti->rt == 1 && ti->blank == 0 && ti->packet == 1)
1528                 return 0;
1529
1530         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1531         return 1;
1532 }
1533
1534 /*
1535  * 0 -- we can write to this disc, 1 -- we can't
1536  */
1537 static int pkt_good_disc(struct pktcdvd_device *pd, disc_information *di)
1538 {
1539         switch (pd->mmc3_profile) {
1540                 case 0x0a: /* CD-RW */
1541                 case 0xffff: /* MMC3 not supported */
1542                         break;
1543                 case 0x1a: /* DVD+RW */
1544                 case 0x13: /* DVD-RW */
1545                 case 0x12: /* DVD-RAM */
1546                         return 0;
1547                 default:
1548                         printk("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1549                         return 1;
1550         }
1551
1552         /*
1553          * for disc type 0xff we should probably reserve a new track.
1554          * but i'm not sure, should we leave this to user apps? probably.
1555          */
1556         if (di->disc_type == 0xff) {
1557                 printk("pktcdvd: Unknown disc. No track?\n");
1558                 return 1;
1559         }
1560
1561         if (di->disc_type != 0x20 && di->disc_type != 0) {
1562                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1563                 return 1;
1564         }
1565
1566         if (di->erasable == 0) {
1567                 printk("pktcdvd: Disc not erasable\n");
1568                 return 1;
1569         }
1570
1571         if (di->border_status == PACKET_SESSION_RESERVED) {
1572                 printk("pktcdvd: Can't write to last track (reserved)\n");
1573                 return 1;
1574         }
1575
1576         return 0;
1577 }
1578
1579 static int pkt_probe_settings(struct pktcdvd_device *pd)
1580 {
1581         struct packet_command cgc;
1582         unsigned char buf[12];
1583         disc_information di;
1584         track_information ti;
1585         int ret, track;
1586
1587         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1588         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1589         cgc.cmd[8] = 8;
1590         ret = pkt_generic_packet(pd, &cgc);
1591         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1592
1593         memset(&di, 0, sizeof(disc_information));
1594         memset(&ti, 0, sizeof(track_information));
1595
1596         if ((ret = pkt_get_disc_info(pd, &di))) {
1597                 printk("failed get_disc\n");
1598                 return ret;
1599         }
1600
1601         if (pkt_good_disc(pd, &di))
1602                 return -ENXIO;
1603
1604         switch (pd->mmc3_profile) {
1605                 case 0x1a: /* DVD+RW */
1606                         printk("pktcdvd: inserted media is DVD+RW\n");
1607                         break;
1608                 case 0x13: /* DVD-RW */
1609                         printk("pktcdvd: inserted media is DVD-RW\n");
1610                         break;
1611                 case 0x12: /* DVD-RAM */
1612                         printk("pktcdvd: inserted media is DVD-RAM\n");
1613                         break;
1614                 default:
1615                         printk("pktcdvd: inserted media is CD-R%s\n", di.erasable ? "W" : "");
1616                         break;
1617         }
1618         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1619
1620         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1621         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1622                 printk("pktcdvd: failed get_track\n");
1623                 return ret;
1624         }
1625
1626         if (pkt_good_track(&ti)) {
1627                 printk("pktcdvd: can't write to this track\n");
1628                 return -ENXIO;
1629         }
1630
1631         /*
1632          * we keep packet size in 512 byte units, makes it easier to
1633          * deal with request calculations.
1634          */
1635         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1636         if (pd->settings.size == 0) {
1637                 printk("pktcdvd: detected zero packet size!\n");
1638                 pd->settings.size = 128;
1639         }
1640         pd->settings.fp = ti.fp;
1641         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1642
1643         if (ti.nwa_v) {
1644                 pd->nwa = be32_to_cpu(ti.next_writable);
1645                 set_bit(PACKET_NWA_VALID, &pd->flags);
1646         }
1647
1648         /*
1649          * in theory we could use lra on -RW media as well and just zero
1650          * blocks that haven't been written yet, but in practice that
1651          * is just a no-go. we'll use that for -R, naturally.
1652          */
1653         if (ti.lra_v) {
1654                 pd->lra = be32_to_cpu(ti.last_rec_address);
1655                 set_bit(PACKET_LRA_VALID, &pd->flags);
1656         } else {
1657                 pd->lra = 0xffffffff;
1658                 set_bit(PACKET_LRA_VALID, &pd->flags);
1659         }
1660
1661         /*
1662          * fine for now
1663          */
1664         pd->settings.link_loss = 7;
1665         pd->settings.write_type = 0;    /* packet */
1666         pd->settings.track_mode = ti.track_mode;
1667
1668         /*
1669          * mode1 or mode2 disc
1670          */
1671         switch (ti.data_mode) {
1672                 case PACKET_MODE1:
1673                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1674                         break;
1675                 case PACKET_MODE2:
1676                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1677                         break;
1678                 default:
1679                         printk("pktcdvd: unknown data mode\n");
1680                         return 1;
1681         }
1682         return 0;
1683 }
1684
1685 /*
1686  * enable/disable write caching on drive
1687  */
1688 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1689 {
1690         struct packet_command cgc;
1691         struct request_sense sense;
1692         unsigned char buf[64];
1693         int ret;
1694
1695         memset(buf, 0, sizeof(buf));
1696         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1697         cgc.sense = &sense;
1698         cgc.buflen = pd->mode_offset + 12;
1699
1700         /*
1701          * caching mode page might not be there, so quiet this command
1702          */
1703         cgc.quiet = 1;
1704
1705         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1706                 return ret;
1707
1708         buf[pd->mode_offset + 10] |= (!!set << 2);
1709
1710         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1711         ret = pkt_mode_select(pd, &cgc);
1712         if (ret) {
1713                 printk("pktcdvd: write caching control failed\n");
1714                 pkt_dump_sense(&cgc);
1715         } else if (!ret && set)
1716                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1717         return ret;
1718 }
1719
1720 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1721 {
1722         struct packet_command cgc;
1723
1724         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1725         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1726         cgc.cmd[4] = lockflag ? 1 : 0;
1727         return pkt_generic_packet(pd, &cgc);
1728 }
1729
1730 /*
1731  * Returns drive maximum write speed
1732  */
1733 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1734 {
1735         struct packet_command cgc;
1736         struct request_sense sense;
1737         unsigned char buf[256+18];
1738         unsigned char *cap_buf;
1739         int ret, offset;
1740
1741         memset(buf, 0, sizeof(buf));
1742         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1743         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1744         cgc.sense = &sense;
1745
1746         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1747         if (ret) {
1748                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1749                              sizeof(struct mode_page_header);
1750                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1751                 if (ret) {
1752                         pkt_dump_sense(&cgc);
1753                         return ret;
1754                 }
1755         }
1756
1757         offset = 20;                        /* Obsoleted field, used by older drives */
1758         if (cap_buf[1] >= 28)
1759                 offset = 28;                /* Current write speed selected */
1760         if (cap_buf[1] >= 30) {
1761                 /* If the drive reports at least one "Logical Unit Write
1762                  * Speed Performance Descriptor Block", use the information
1763                  * in the first block. (contains the highest speed)
1764                  */
1765                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1766                 if (num_spdb > 0)
1767                         offset = 34;
1768         }
1769
1770         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1771         return 0;
1772 }
1773
1774 /* These tables from cdrecord - I don't have orange book */
1775 /* standard speed CD-RW (1-4x) */
1776 static char clv_to_speed[16] = {
1777         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1778            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1779 };
1780 /* high speed CD-RW (-10x) */
1781 static char hs_clv_to_speed[16] = {
1782         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1783            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1784 };
1785 /* ultra high speed CD-RW */
1786 static char us_clv_to_speed[16] = {
1787         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1788            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1789 };
1790
1791 /*
1792  * reads the maximum media speed from ATIP
1793  */
1794 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1795 {
1796         struct packet_command cgc;
1797         struct request_sense sense;
1798         unsigned char buf[64];
1799         unsigned int size, st, sp;
1800         int ret;
1801
1802         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1803         cgc.sense = &sense;
1804         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1805         cgc.cmd[1] = 2;
1806         cgc.cmd[2] = 4; /* READ ATIP */
1807         cgc.cmd[8] = 2;
1808         ret = pkt_generic_packet(pd, &cgc);
1809         if (ret) {
1810                 pkt_dump_sense(&cgc);
1811                 return ret;
1812         }
1813         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1814         if (size > sizeof(buf))
1815                 size = sizeof(buf);
1816
1817         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1818         cgc.sense = &sense;
1819         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1820         cgc.cmd[1] = 2;
1821         cgc.cmd[2] = 4;
1822         cgc.cmd[8] = size;
1823         ret = pkt_generic_packet(pd, &cgc);
1824         if (ret) {
1825                 pkt_dump_sense(&cgc);
1826                 return ret;
1827         }
1828
1829         if (!buf[6] & 0x40) {
1830                 printk("pktcdvd: Disc type is not CD-RW\n");
1831                 return 1;
1832         }
1833         if (!buf[6] & 0x4) {
1834                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1835                 return 1;
1836         }
1837
1838         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1839
1840         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1841
1842         /* Info from cdrecord */
1843         switch (st) {
1844                 case 0: /* standard speed */
1845                         *speed = clv_to_speed[sp];
1846                         break;
1847                 case 1: /* high speed */
1848                         *speed = hs_clv_to_speed[sp];
1849                         break;
1850                 case 2: /* ultra high speed */
1851                         *speed = us_clv_to_speed[sp];
1852                         break;
1853                 default:
1854                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1855                         return 1;
1856         }
1857         if (*speed) {
1858                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1859                 return 0;
1860         } else {
1861                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1862                 return 1;
1863         }
1864 }
1865
1866 static int pkt_perform_opc(struct pktcdvd_device *pd)
1867 {
1868         struct packet_command cgc;
1869         struct request_sense sense;
1870         int ret;
1871
1872         VPRINTK("pktcdvd: Performing OPC\n");
1873
1874         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1875         cgc.sense = &sense;
1876         cgc.timeout = 60*HZ;
1877         cgc.cmd[0] = GPCMD_SEND_OPC;
1878         cgc.cmd[1] = 1;
1879         if ((ret = pkt_generic_packet(pd, &cgc)))
1880                 pkt_dump_sense(&cgc);
1881         return ret;
1882 }
1883
1884 static int pkt_open_write(struct pktcdvd_device *pd)
1885 {
1886         int ret;
1887         unsigned int write_speed, media_write_speed, read_speed;
1888
1889         if ((ret = pkt_probe_settings(pd))) {
1890                 DPRINTK("pktcdvd: %s failed probe\n", pd->name);
1891                 return -EIO;
1892         }
1893
1894         if ((ret = pkt_set_write_settings(pd))) {
1895                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1896                 return -EIO;
1897         }
1898
1899         pkt_write_caching(pd, USE_WCACHING);
1900
1901         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1902                 write_speed = 16 * 177;
1903         switch (pd->mmc3_profile) {
1904                 case 0x13: /* DVD-RW */
1905                 case 0x1a: /* DVD+RW */
1906                 case 0x12: /* DVD-RAM */
1907                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1908                         break;
1909                 default:
1910                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1911                                 media_write_speed = 16;
1912                         write_speed = min(write_speed, media_write_speed * 177);
1913                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1914                         break;
1915         }
1916         read_speed = write_speed;
1917
1918         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1919                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1920                 return -EIO;
1921         }
1922         pd->write_speed = write_speed;
1923         pd->read_speed = read_speed;
1924
1925         if ((ret = pkt_perform_opc(pd))) {
1926                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1927         }
1928
1929         return 0;
1930 }
1931
1932 /*
1933  * called at open time.
1934  */
1935 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1936 {
1937         int ret;
1938         long lba;
1939         request_queue_t *q;
1940
1941         /*
1942          * We need to re-open the cdrom device without O_NONBLOCK to be able
1943          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1944          * so bdget() can't fail.
1945          */
1946         bdget(pd->bdev->bd_dev);
1947         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1948                 goto out;
1949
1950         if ((ret = pkt_get_last_written(pd, &lba))) {
1951                 printk("pktcdvd: pkt_get_last_written failed\n");
1952                 goto out_putdev;
1953         }
1954
1955         set_capacity(pd->disk, lba << 2);
1956         set_capacity(pd->bdev->bd_disk, lba << 2);
1957         bd_set_size(pd->bdev, (loff_t)lba << 11);
1958
1959         q = bdev_get_queue(pd->bdev);
1960         if (write) {
1961                 if ((ret = pkt_open_write(pd)))
1962                         goto out_putdev;
1963                 /*
1964                  * Some CDRW drives can not handle writes larger than one packet,
1965                  * even if the size is a multiple of the packet size.
1966                  */
1967                 spin_lock_irq(q->queue_lock);
1968                 blk_queue_max_sectors(q, pd->settings.size);
1969                 spin_unlock_irq(q->queue_lock);
1970                 set_bit(PACKET_WRITABLE, &pd->flags);
1971         } else {
1972                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1973                 clear_bit(PACKET_WRITABLE, &pd->flags);
1974         }
1975
1976         if ((ret = pkt_set_segment_merging(pd, q)))
1977                 goto out_putdev;
1978
1979         if (write)
1980                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1981
1982         return 0;
1983
1984 out_putdev:
1985         blkdev_put(pd->bdev);
1986 out:
1987         return ret;
1988 }
1989
1990 /*
1991  * called when the device is closed. makes sure that the device flushes
1992  * the internal cache before we close.
1993  */
1994 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
1995 {
1996         if (flush && pkt_flush_cache(pd))
1997                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
1998
1999         pkt_lock_door(pd, 0);
2000
2001         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2002         blkdev_put(pd->bdev);
2003 }
2004
2005 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2006 {
2007         if (dev_minor >= MAX_WRITERS)
2008                 return NULL;
2009         return pkt_devs[dev_minor];
2010 }
2011
2012 static int pkt_open(struct inode *inode, struct file *file)
2013 {
2014         struct pktcdvd_device *pd = NULL;
2015         int ret;
2016
2017         VPRINTK("pktcdvd: entering open\n");
2018
2019         down(&ctl_mutex);
2020         pd = pkt_find_dev_from_minor(iminor(inode));
2021         if (!pd) {
2022                 ret = -ENODEV;
2023                 goto out;
2024         }
2025         BUG_ON(pd->refcnt < 0);
2026
2027         pd->refcnt++;
2028         if (pd->refcnt > 1) {
2029                 if ((file->f_mode & FMODE_WRITE) &&
2030                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2031                         ret = -EBUSY;
2032                         goto out_dec;
2033                 }
2034         } else {
2035                 if (pkt_open_dev(pd, file->f_mode & FMODE_WRITE)) {
2036                         ret = -EIO;
2037                         goto out_dec;
2038                 }
2039                 /*
2040                  * needed here as well, since ext2 (among others) may change
2041                  * the blocksize at mount time
2042                  */
2043                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2044         }
2045
2046         up(&ctl_mutex);
2047         return 0;
2048
2049 out_dec:
2050         pd->refcnt--;
2051 out:
2052         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2053         up(&ctl_mutex);
2054         return ret;
2055 }
2056
2057 static int pkt_close(struct inode *inode, struct file *file)
2058 {
2059         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2060         int ret = 0;
2061
2062         down(&ctl_mutex);
2063         pd->refcnt--;
2064         BUG_ON(pd->refcnt < 0);
2065         if (pd->refcnt == 0) {
2066                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2067                 pkt_release_dev(pd, flush);
2068         }
2069         up(&ctl_mutex);
2070         return ret;
2071 }
2072
2073
2074 static void *psd_pool_alloc(unsigned int __nocast gfp_mask, void *data)
2075 {
2076         return kmalloc(sizeof(struct packet_stacked_data), gfp_mask);
2077 }
2078
2079 static void psd_pool_free(void *ptr, void *data)
2080 {
2081         kfree(ptr);
2082 }
2083
2084 static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int err)
2085 {
2086         struct packet_stacked_data *psd = bio->bi_private;
2087         struct pktcdvd_device *pd = psd->pd;
2088
2089         if (bio->bi_size)
2090                 return 1;
2091
2092         bio_put(bio);
2093         bio_endio(psd->bio, psd->bio->bi_size, err);
2094         mempool_free(psd, psd_pool);
2095         pkt_bio_finished(pd);
2096         return 0;
2097 }
2098
2099 static int pkt_make_request(request_queue_t *q, struct bio *bio)
2100 {
2101         struct pktcdvd_device *pd;
2102         char b[BDEVNAME_SIZE];
2103         sector_t zone;
2104         struct packet_data *pkt;
2105         int was_empty, blocked_bio;
2106         struct pkt_rb_node *node;
2107
2108         pd = q->queuedata;
2109         if (!pd) {
2110                 printk("pktcdvd: %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2111                 goto end_io;
2112         }
2113
2114         /*
2115          * Clone READ bios so we can have our own bi_end_io callback.
2116          */
2117         if (bio_data_dir(bio) == READ) {
2118                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2119                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2120
2121                 psd->pd = pd;
2122                 psd->bio = bio;
2123                 cloned_bio->bi_bdev = pd->bdev;
2124                 cloned_bio->bi_private = psd;
2125                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2126                 pd->stats.secs_r += bio->bi_size >> 9;
2127                 pkt_queue_bio(pd, cloned_bio);
2128                 return 0;
2129         }
2130
2131         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2132                 printk("pktcdvd: WRITE for ro device %s (%llu)\n",
2133                         pd->name, (unsigned long long)bio->bi_sector);
2134                 goto end_io;
2135         }
2136
2137         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2138                 printk("pktcdvd: wrong bio size\n");
2139                 goto end_io;
2140         }
2141
2142         blk_queue_bounce(q, &bio);
2143
2144         zone = ZONE(bio->bi_sector, pd);
2145         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2146                 (unsigned long long)bio->bi_sector,
2147                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2148
2149         /* Check if we have to split the bio */
2150         {
2151                 struct bio_pair *bp;
2152                 sector_t last_zone;
2153                 int first_sectors;
2154
2155                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2156                 if (last_zone != zone) {
2157                         BUG_ON(last_zone != zone + pd->settings.size);
2158                         first_sectors = last_zone - bio->bi_sector;
2159                         bp = bio_split(bio, bio_split_pool, first_sectors);
2160                         BUG_ON(!bp);
2161                         pkt_make_request(q, &bp->bio1);
2162                         pkt_make_request(q, &bp->bio2);
2163                         bio_pair_release(bp);
2164                         return 0;
2165                 }
2166         }
2167
2168         /*
2169          * If we find a matching packet in state WAITING or READ_WAIT, we can
2170          * just append this bio to that packet.
2171          */
2172         spin_lock(&pd->cdrw.active_list_lock);
2173         blocked_bio = 0;
2174         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2175                 if (pkt->sector == zone) {
2176                         spin_lock(&pkt->lock);
2177                         if ((pkt->state == PACKET_WAITING_STATE) ||
2178                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2179                                 pkt_add_list_last(bio, &pkt->orig_bios,
2180                                                   &pkt->orig_bios_tail);
2181                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2182                                 if ((pkt->write_size >= pkt->frames) &&
2183                                     (pkt->state == PACKET_WAITING_STATE)) {
2184                                         atomic_inc(&pkt->run_sm);
2185                                         wake_up(&pd->wqueue);
2186                                 }
2187                                 spin_unlock(&pkt->lock);
2188                                 spin_unlock(&pd->cdrw.active_list_lock);
2189                                 return 0;
2190                         } else {
2191                                 blocked_bio = 1;
2192                         }
2193                         spin_unlock(&pkt->lock);
2194                 }
2195         }
2196         spin_unlock(&pd->cdrw.active_list_lock);
2197
2198         /*
2199          * No matching packet found. Store the bio in the work queue.
2200          */
2201         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2202         BUG_ON(!node);
2203         node->bio = bio;
2204         spin_lock(&pd->lock);
2205         BUG_ON(pd->bio_queue_size < 0);
2206         was_empty = (pd->bio_queue_size == 0);
2207         pkt_rbtree_insert(pd, node);
2208         spin_unlock(&pd->lock);
2209
2210         /*
2211          * Wake up the worker thread.
2212          */
2213         atomic_set(&pd->scan_queue, 1);
2214         if (was_empty) {
2215                 /* This wake_up is required for correct operation */
2216                 wake_up(&pd->wqueue);
2217         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2218                 /*
2219                  * This wake up is not required for correct operation,
2220                  * but improves performance in some cases.
2221                  */
2222                 wake_up(&pd->wqueue);
2223         }
2224         return 0;
2225 end_io:
2226         bio_io_error(bio, bio->bi_size);
2227         return 0;
2228 }
2229
2230
2231
2232 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2233 {
2234         struct pktcdvd_device *pd = q->queuedata;
2235         sector_t zone = ZONE(bio->bi_sector, pd);
2236         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2237         int remaining = (pd->settings.size << 9) - used;
2238         int remaining2;
2239
2240         /*
2241          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2242          * boundary, pkt_make_request() will split the bio.
2243          */
2244         remaining2 = PAGE_SIZE - bio->bi_size;
2245         remaining = max(remaining, remaining2);
2246
2247         BUG_ON(remaining < 0);
2248         return remaining;
2249 }
2250
2251 static void pkt_init_queue(struct pktcdvd_device *pd)
2252 {
2253         request_queue_t *q = pd->disk->queue;
2254
2255         blk_queue_make_request(q, pkt_make_request);
2256         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2257         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2258         blk_queue_merge_bvec(q, pkt_merge_bvec);
2259         q->queuedata = pd;
2260 }
2261
2262 static int pkt_seq_show(struct seq_file *m, void *p)
2263 {
2264         struct pktcdvd_device *pd = m->private;
2265         char *msg;
2266         char bdev_buf[BDEVNAME_SIZE];
2267         int states[PACKET_NUM_STATES];
2268
2269         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2270                    bdevname(pd->bdev, bdev_buf));
2271
2272         seq_printf(m, "\nSettings:\n");
2273         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2274
2275         if (pd->settings.write_type == 0)
2276                 msg = "Packet";
2277         else
2278                 msg = "Unknown";
2279         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2280
2281         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2282         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2283
2284         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2285
2286         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2287                 msg = "Mode 1";
2288         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2289                 msg = "Mode 2";
2290         else
2291                 msg = "Unknown";
2292         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2293
2294         seq_printf(m, "\nStatistics:\n");
2295         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2296         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2297         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2298         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2299         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2300
2301         seq_printf(m, "\nMisc:\n");
2302         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2303         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2304         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2305         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2306         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2307         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2308
2309         seq_printf(m, "\nQueue state:\n");
2310         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2311         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2312         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2313
2314         pkt_count_states(pd, states);
2315         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2316                    states[0], states[1], states[2], states[3], states[4], states[5]);
2317
2318         return 0;
2319 }
2320
2321 static int pkt_seq_open(struct inode *inode, struct file *file)
2322 {
2323         return single_open(file, pkt_seq_show, PDE(inode)->data);
2324 }
2325
2326 static struct file_operations pkt_proc_fops = {
2327         .open   = pkt_seq_open,
2328         .read   = seq_read,
2329         .llseek = seq_lseek,
2330         .release = single_release
2331 };
2332
2333 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2334 {
2335         int i;
2336         int ret = 0;
2337         char b[BDEVNAME_SIZE];
2338         struct proc_dir_entry *proc;
2339         struct block_device *bdev;
2340
2341         if (pd->pkt_dev == dev) {
2342                 printk("pktcdvd: Recursive setup not allowed\n");
2343                 return -EBUSY;
2344         }
2345         for (i = 0; i < MAX_WRITERS; i++) {
2346                 struct pktcdvd_device *pd2 = pkt_devs[i];
2347                 if (!pd2)
2348                         continue;
2349                 if (pd2->bdev->bd_dev == dev) {
2350                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2351                         return -EBUSY;
2352                 }
2353                 if (pd2->pkt_dev == dev) {
2354                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2355                         return -EBUSY;
2356                 }
2357         }
2358
2359         bdev = bdget(dev);
2360         if (!bdev)
2361                 return -ENOMEM;
2362         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2363         if (ret)
2364                 return ret;
2365
2366         /* This is safe, since we have a reference from open(). */
2367         __module_get(THIS_MODULE);
2368
2369         if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2370                 printk("pktcdvd: not enough memory for buffers\n");
2371                 ret = -ENOMEM;
2372                 goto out_mem;
2373         }
2374
2375         pd->bdev = bdev;
2376         set_blocksize(bdev, CD_FRAMESIZE);
2377
2378         pkt_init_queue(pd);
2379
2380         atomic_set(&pd->cdrw.pending_bios, 0);
2381         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2382         if (IS_ERR(pd->cdrw.thread)) {
2383                 printk("pktcdvd: can't start kernel thread\n");
2384                 ret = -ENOMEM;
2385                 goto out_thread;
2386         }
2387
2388         proc = create_proc_entry(pd->name, 0, pkt_proc);
2389         if (proc) {
2390                 proc->data = pd;
2391                 proc->proc_fops = &pkt_proc_fops;
2392         }
2393         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2394         return 0;
2395
2396 out_thread:
2397         pkt_shrink_pktlist(pd);
2398 out_mem:
2399         blkdev_put(bdev);
2400         /* This is safe: open() is still holding a reference. */
2401         module_put(THIS_MODULE);
2402         return ret;
2403 }
2404
2405 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2406 {
2407         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2408
2409         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2410         BUG_ON(!pd);
2411
2412         switch (cmd) {
2413         /*
2414          * forward selected CDROM ioctls to CD-ROM, for UDF
2415          */
2416         case CDROMMULTISESSION:
2417         case CDROMREADTOCENTRY:
2418         case CDROM_LAST_WRITTEN:
2419         case CDROM_SEND_PACKET:
2420         case SCSI_IOCTL_SEND_COMMAND:
2421                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2422
2423         case CDROMEJECT:
2424                 /*
2425                  * The door gets locked when the device is opened, so we
2426                  * have to unlock it or else the eject command fails.
2427                  */
2428                 pkt_lock_door(pd, 0);
2429                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2430
2431         default:
2432                 printk("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2433                 return -ENOTTY;
2434         }
2435
2436         return 0;
2437 }
2438
2439 static int pkt_media_changed(struct gendisk *disk)
2440 {
2441         struct pktcdvd_device *pd = disk->private_data;
2442         struct gendisk *attached_disk;
2443
2444         if (!pd)
2445                 return 0;
2446         if (!pd->bdev)
2447                 return 0;
2448         attached_disk = pd->bdev->bd_disk;
2449         if (!attached_disk)
2450                 return 0;
2451         return attached_disk->fops->media_changed(attached_disk);
2452 }
2453
2454 static struct block_device_operations pktcdvd_ops = {
2455         .owner =                THIS_MODULE,
2456         .open =                 pkt_open,
2457         .release =              pkt_close,
2458         .ioctl =                pkt_ioctl,
2459         .media_changed =        pkt_media_changed,
2460 };
2461
2462 /*
2463  * Set up mapping from pktcdvd device to CD-ROM device.
2464  */
2465 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2466 {
2467         int idx;
2468         int ret = -ENOMEM;
2469         struct pktcdvd_device *pd;
2470         struct gendisk *disk;
2471         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2472
2473         for (idx = 0; idx < MAX_WRITERS; idx++)
2474                 if (!pkt_devs[idx])
2475                         break;
2476         if (idx == MAX_WRITERS) {
2477                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2478                 return -EBUSY;
2479         }
2480
2481         pd = kmalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2482         if (!pd)
2483                 return ret;
2484         memset(pd, 0, sizeof(struct pktcdvd_device));
2485
2486         pd->rb_pool = mempool_create(PKT_RB_POOL_SIZE, pkt_rb_alloc, pkt_rb_free, NULL);
2487         if (!pd->rb_pool)
2488                 goto out_mem;
2489
2490         disk = alloc_disk(1);
2491         if (!disk)
2492                 goto out_mem;
2493         pd->disk = disk;
2494
2495         spin_lock_init(&pd->lock);
2496         spin_lock_init(&pd->iosched.lock);
2497         sprintf(pd->name, "pktcdvd%d", idx);
2498         init_waitqueue_head(&pd->wqueue);
2499         pd->bio_queue = RB_ROOT;
2500
2501         disk->major = pkt_major;
2502         disk->first_minor = idx;
2503         disk->fops = &pktcdvd_ops;
2504         disk->flags = GENHD_FL_REMOVABLE;
2505         sprintf(disk->disk_name, "pktcdvd%d", idx);
2506         disk->private_data = pd;
2507         disk->queue = blk_alloc_queue(GFP_KERNEL);
2508         if (!disk->queue)
2509                 goto out_mem2;
2510
2511         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2512         ret = pkt_new_dev(pd, dev);
2513         if (ret)
2514                 goto out_new_dev;
2515
2516         add_disk(disk);
2517         pkt_devs[idx] = pd;
2518         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2519         return 0;
2520
2521 out_new_dev:
2522         blk_put_queue(disk->queue);
2523 out_mem2:
2524         put_disk(disk);
2525 out_mem:
2526         if (pd->rb_pool)
2527                 mempool_destroy(pd->rb_pool);
2528         kfree(pd);
2529         return ret;
2530 }
2531
2532 /*
2533  * Tear down mapping from pktcdvd device to CD-ROM device.
2534  */
2535 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2536 {
2537         struct pktcdvd_device *pd;
2538         int idx;
2539         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2540
2541         for (idx = 0; idx < MAX_WRITERS; idx++) {
2542                 pd = pkt_devs[idx];
2543                 if (pd && (pd->pkt_dev == pkt_dev))
2544                         break;
2545         }
2546         if (idx == MAX_WRITERS) {
2547                 DPRINTK("pktcdvd: dev not setup\n");
2548                 return -ENXIO;
2549         }
2550
2551         if (pd->refcnt > 0)
2552                 return -EBUSY;
2553
2554         if (!IS_ERR(pd->cdrw.thread))
2555                 kthread_stop(pd->cdrw.thread);
2556
2557         blkdev_put(pd->bdev);
2558
2559         pkt_shrink_pktlist(pd);
2560
2561         remove_proc_entry(pd->name, pkt_proc);
2562         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2563
2564         del_gendisk(pd->disk);
2565         blk_put_queue(pd->disk->queue);
2566         put_disk(pd->disk);
2567
2568         pkt_devs[idx] = NULL;
2569         mempool_destroy(pd->rb_pool);
2570         kfree(pd);
2571
2572         /* This is safe: open() is still holding a reference. */
2573         module_put(THIS_MODULE);
2574         return 0;
2575 }
2576
2577 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2578 {
2579         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2580         if (pd) {
2581                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2582                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2583         } else {
2584                 ctrl_cmd->dev = 0;
2585                 ctrl_cmd->pkt_dev = 0;
2586         }
2587         ctrl_cmd->num_devices = MAX_WRITERS;
2588 }
2589
2590 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2591 {
2592         void __user *argp = (void __user *)arg;
2593         struct pkt_ctrl_command ctrl_cmd;
2594         int ret = 0;
2595
2596         if (cmd != PACKET_CTRL_CMD)
2597                 return -ENOTTY;
2598
2599         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2600                 return -EFAULT;
2601
2602         switch (ctrl_cmd.command) {
2603         case PKT_CTRL_CMD_SETUP:
2604                 if (!capable(CAP_SYS_ADMIN))
2605                         return -EPERM;
2606                 down(&ctl_mutex);
2607                 ret = pkt_setup_dev(&ctrl_cmd);
2608                 up(&ctl_mutex);
2609                 break;
2610         case PKT_CTRL_CMD_TEARDOWN:
2611                 if (!capable(CAP_SYS_ADMIN))
2612                         return -EPERM;
2613                 down(&ctl_mutex);
2614                 ret = pkt_remove_dev(&ctrl_cmd);
2615                 up(&ctl_mutex);
2616                 break;
2617         case PKT_CTRL_CMD_STATUS:
2618                 down(&ctl_mutex);
2619                 pkt_get_status(&ctrl_cmd);
2620                 up(&ctl_mutex);
2621                 break;
2622         default:
2623                 return -ENOTTY;
2624         }
2625
2626         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2627                 return -EFAULT;
2628         return ret;
2629 }
2630
2631
2632 static struct file_operations pkt_ctl_fops = {
2633         .ioctl   = pkt_ctl_ioctl,
2634         .owner   = THIS_MODULE,
2635 };
2636
2637 static struct miscdevice pkt_misc = {
2638         .minor          = MISC_DYNAMIC_MINOR,
2639         .name           = "pktcdvd",
2640         .devfs_name     = "pktcdvd/control",
2641         .fops           = &pkt_ctl_fops
2642 };
2643
2644 static int __init pkt_init(void)
2645 {
2646         int ret;
2647
2648         psd_pool = mempool_create(PSD_POOL_SIZE, psd_pool_alloc, psd_pool_free, NULL);
2649         if (!psd_pool)
2650                 return -ENOMEM;
2651
2652         ret = register_blkdev(pkt_major, "pktcdvd");
2653         if (ret < 0) {
2654                 printk("pktcdvd: Unable to register block device\n");
2655                 goto out2;
2656         }
2657         if (!pkt_major)
2658                 pkt_major = ret;
2659
2660         ret = misc_register(&pkt_misc);
2661         if (ret) {
2662                 printk("pktcdvd: Unable to register misc device\n");
2663                 goto out;
2664         }
2665
2666         init_MUTEX(&ctl_mutex);
2667
2668         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2669
2670         DPRINTK("pktcdvd: %s\n", VERSION_CODE);
2671         return 0;
2672
2673 out:
2674         unregister_blkdev(pkt_major, "pktcdvd");
2675 out2:
2676         mempool_destroy(psd_pool);
2677         return ret;
2678 }
2679
2680 static void __exit pkt_exit(void)
2681 {
2682         remove_proc_entry("pktcdvd", proc_root_driver);
2683         misc_deregister(&pkt_misc);
2684         unregister_blkdev(pkt_major, "pktcdvd");
2685         mempool_destroy(psd_pool);
2686 }
2687
2688 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2689 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2690 MODULE_LICENSE("GPL");
2691
2692 module_init(pkt_init);
2693 module_exit(pkt_exit);