[PATCH] Cleanup patch for process freezing
[linux-2.6.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                         try_to_freeze();
1255
1256                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1257                                 if (!pkt->sleep_time)
1258                                         continue;
1259                                 pkt->sleep_time -= min_sleep_time - residue;
1260                                 if (pkt->sleep_time <= 0) {
1261                                         pkt->sleep_time = 0;
1262                                         atomic_inc(&pkt->run_sm);
1263                                 }
1264                         }
1265
1266                         if (signal_pending(current)) {
1267                                 flush_signals(current);
1268                         }
1269                         if (kthread_should_stop())
1270                                 break;
1271                 }
1272 work_to_do:
1273                 set_current_state(TASK_RUNNING);
1274                 remove_wait_queue(&pd->wqueue, &wait);
1275
1276                 if (kthread_should_stop())
1277                         break;
1278
1279                 /*
1280                  * if pkt_handle_queue returns true, we can queue
1281                  * another request.
1282                  */
1283                 while (pkt_handle_queue(pd))
1284                         ;
1285
1286                 /*
1287                  * Handle packet state machine
1288                  */
1289                 pkt_handle_packets(pd);
1290
1291                 /*
1292                  * Handle iosched queues
1293                  */
1294                 pkt_iosched_process_queue(pd);
1295         }
1296
1297         return 0;
1298 }
1299
1300 static void pkt_print_settings(struct pktcdvd_device *pd)
1301 {
1302         printk("pktcdvd: %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1303         printk("%u blocks, ", pd->settings.size >> 2);
1304         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1305 }
1306
1307 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1308 {
1309         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1310
1311         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1312         cgc->cmd[2] = page_code | (page_control << 6);
1313         cgc->cmd[7] = cgc->buflen >> 8;
1314         cgc->cmd[8] = cgc->buflen & 0xff;
1315         cgc->data_direction = CGC_DATA_READ;
1316         return pkt_generic_packet(pd, cgc);
1317 }
1318
1319 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1320 {
1321         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1322         memset(cgc->buffer, 0, 2);
1323         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1324         cgc->cmd[1] = 0x10;             /* PF */
1325         cgc->cmd[7] = cgc->buflen >> 8;
1326         cgc->cmd[8] = cgc->buflen & 0xff;
1327         cgc->data_direction = CGC_DATA_WRITE;
1328         return pkt_generic_packet(pd, cgc);
1329 }
1330
1331 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1332 {
1333         struct packet_command cgc;
1334         int ret;
1335
1336         /* set up command and get the disc info */
1337         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1338         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1339         cgc.cmd[8] = cgc.buflen = 2;
1340         cgc.quiet = 1;
1341
1342         if ((ret = pkt_generic_packet(pd, &cgc)))
1343                 return ret;
1344
1345         /* not all drives have the same disc_info length, so requeue
1346          * packet with the length the drive tells us it can supply
1347          */
1348         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1349                      sizeof(di->disc_information_length);
1350
1351         if (cgc.buflen > sizeof(disc_information))
1352                 cgc.buflen = sizeof(disc_information);
1353
1354         cgc.cmd[8] = cgc.buflen;
1355         return pkt_generic_packet(pd, &cgc);
1356 }
1357
1358 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1359 {
1360         struct packet_command cgc;
1361         int ret;
1362
1363         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1364         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1365         cgc.cmd[1] = type & 3;
1366         cgc.cmd[4] = (track & 0xff00) >> 8;
1367         cgc.cmd[5] = track & 0xff;
1368         cgc.cmd[8] = 8;
1369         cgc.quiet = 1;
1370
1371         if ((ret = pkt_generic_packet(pd, &cgc)))
1372                 return ret;
1373
1374         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1375                      sizeof(ti->track_information_length);
1376
1377         if (cgc.buflen > sizeof(track_information))
1378                 cgc.buflen = sizeof(track_information);
1379
1380         cgc.cmd[8] = cgc.buflen;
1381         return pkt_generic_packet(pd, &cgc);
1382 }
1383
1384 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1385 {
1386         disc_information di;
1387         track_information ti;
1388         __u32 last_track;
1389         int ret = -1;
1390
1391         if ((ret = pkt_get_disc_info(pd, &di)))
1392                 return ret;
1393
1394         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1395         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1396                 return ret;
1397
1398         /* if this track is blank, try the previous. */
1399         if (ti.blank) {
1400                 last_track--;
1401                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1402                         return ret;
1403         }
1404
1405         /* if last recorded field is valid, return it. */
1406         if (ti.lra_v) {
1407                 *last_written = be32_to_cpu(ti.last_rec_address);
1408         } else {
1409                 /* make it up instead */
1410                 *last_written = be32_to_cpu(ti.track_start) +
1411                                 be32_to_cpu(ti.track_size);
1412                 if (ti.free_blocks)
1413                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1414         }
1415         return 0;
1416 }
1417
1418 /*
1419  * write mode select package based on pd->settings
1420  */
1421 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1422 {
1423         struct packet_command cgc;
1424         struct request_sense sense;
1425         write_param_page *wp;
1426         char buffer[128];
1427         int ret, size;
1428
1429         /* doesn't apply to DVD+RW or DVD-RAM */
1430         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1431                 return 0;
1432
1433         memset(buffer, 0, sizeof(buffer));
1434         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1435         cgc.sense = &sense;
1436         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1437                 pkt_dump_sense(&cgc);
1438                 return ret;
1439         }
1440
1441         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1442         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1443         if (size > sizeof(buffer))
1444                 size = sizeof(buffer);
1445
1446         /*
1447          * now get it all
1448          */
1449         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1450         cgc.sense = &sense;
1451         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1452                 pkt_dump_sense(&cgc);
1453                 return ret;
1454         }
1455
1456         /*
1457          * write page is offset header + block descriptor length
1458          */
1459         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1460
1461         wp->fp = pd->settings.fp;
1462         wp->track_mode = pd->settings.track_mode;
1463         wp->write_type = pd->settings.write_type;
1464         wp->data_block_type = pd->settings.block_mode;
1465
1466         wp->multi_session = 0;
1467
1468 #ifdef PACKET_USE_LS
1469         wp->link_size = 7;
1470         wp->ls_v = 1;
1471 #endif
1472
1473         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1474                 wp->session_format = 0;
1475                 wp->subhdr2 = 0x20;
1476         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1477                 wp->session_format = 0x20;
1478                 wp->subhdr2 = 8;
1479 #if 0
1480                 wp->mcn[0] = 0x80;
1481                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1482 #endif
1483         } else {
1484                 /*
1485                  * paranoia
1486                  */
1487                 printk("pktcdvd: write mode wrong %d\n", wp->data_block_type);
1488                 return 1;
1489         }
1490         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1491
1492         cgc.buflen = cgc.cmd[8] = size;
1493         if ((ret = pkt_mode_select(pd, &cgc))) {
1494                 pkt_dump_sense(&cgc);
1495                 return ret;
1496         }
1497
1498         pkt_print_settings(pd);
1499         return 0;
1500 }
1501
1502 /*
1503  * 0 -- we can write to this track, 1 -- we can't
1504  */
1505 static int pkt_good_track(track_information *ti)
1506 {
1507         /*
1508          * only good for CD-RW at the moment, not DVD-RW
1509          */
1510
1511         /*
1512          * FIXME: only for FP
1513          */
1514         if (ti->fp == 0)
1515                 return 0;
1516
1517         /*
1518          * "good" settings as per Mt Fuji.
1519          */
1520         if (ti->rt == 0 && ti->blank == 0 && ti->packet == 1)
1521                 return 0;
1522
1523         if (ti->rt == 0 && ti->blank == 1 && ti->packet == 1)
1524                 return 0;
1525
1526         if (ti->rt == 1 && ti->blank == 0 && ti->packet == 1)
1527                 return 0;
1528
1529         printk("pktcdvd: bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1530         return 1;
1531 }
1532
1533 /*
1534  * 0 -- we can write to this disc, 1 -- we can't
1535  */
1536 static int pkt_good_disc(struct pktcdvd_device *pd, disc_information *di)
1537 {
1538         switch (pd->mmc3_profile) {
1539                 case 0x0a: /* CD-RW */
1540                 case 0xffff: /* MMC3 not supported */
1541                         break;
1542                 case 0x1a: /* DVD+RW */
1543                 case 0x13: /* DVD-RW */
1544                 case 0x12: /* DVD-RAM */
1545                         return 0;
1546                 default:
1547                         printk("pktcdvd: Wrong disc profile (%x)\n", pd->mmc3_profile);
1548                         return 1;
1549         }
1550
1551         /*
1552          * for disc type 0xff we should probably reserve a new track.
1553          * but i'm not sure, should we leave this to user apps? probably.
1554          */
1555         if (di->disc_type == 0xff) {
1556                 printk("pktcdvd: Unknown disc. No track?\n");
1557                 return 1;
1558         }
1559
1560         if (di->disc_type != 0x20 && di->disc_type != 0) {
1561                 printk("pktcdvd: Wrong disc type (%x)\n", di->disc_type);
1562                 return 1;
1563         }
1564
1565         if (di->erasable == 0) {
1566                 printk("pktcdvd: Disc not erasable\n");
1567                 return 1;
1568         }
1569
1570         if (di->border_status == PACKET_SESSION_RESERVED) {
1571                 printk("pktcdvd: Can't write to last track (reserved)\n");
1572                 return 1;
1573         }
1574
1575         return 0;
1576 }
1577
1578 static int pkt_probe_settings(struct pktcdvd_device *pd)
1579 {
1580         struct packet_command cgc;
1581         unsigned char buf[12];
1582         disc_information di;
1583         track_information ti;
1584         int ret, track;
1585
1586         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1587         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1588         cgc.cmd[8] = 8;
1589         ret = pkt_generic_packet(pd, &cgc);
1590         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1591
1592         memset(&di, 0, sizeof(disc_information));
1593         memset(&ti, 0, sizeof(track_information));
1594
1595         if ((ret = pkt_get_disc_info(pd, &di))) {
1596                 printk("failed get_disc\n");
1597                 return ret;
1598         }
1599
1600         if (pkt_good_disc(pd, &di))
1601                 return -ENXIO;
1602
1603         switch (pd->mmc3_profile) {
1604                 case 0x1a: /* DVD+RW */
1605                         printk("pktcdvd: inserted media is DVD+RW\n");
1606                         break;
1607                 case 0x13: /* DVD-RW */
1608                         printk("pktcdvd: inserted media is DVD-RW\n");
1609                         break;
1610                 case 0x12: /* DVD-RAM */
1611                         printk("pktcdvd: inserted media is DVD-RAM\n");
1612                         break;
1613                 default:
1614                         printk("pktcdvd: inserted media is CD-R%s\n", di.erasable ? "W" : "");
1615                         break;
1616         }
1617         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1618
1619         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1620         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1621                 printk("pktcdvd: failed get_track\n");
1622                 return ret;
1623         }
1624
1625         if (pkt_good_track(&ti)) {
1626                 printk("pktcdvd: can't write to this track\n");
1627                 return -ENXIO;
1628         }
1629
1630         /*
1631          * we keep packet size in 512 byte units, makes it easier to
1632          * deal with request calculations.
1633          */
1634         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1635         if (pd->settings.size == 0) {
1636                 printk("pktcdvd: detected zero packet size!\n");
1637                 pd->settings.size = 128;
1638         }
1639         pd->settings.fp = ti.fp;
1640         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1641
1642         if (ti.nwa_v) {
1643                 pd->nwa = be32_to_cpu(ti.next_writable);
1644                 set_bit(PACKET_NWA_VALID, &pd->flags);
1645         }
1646
1647         /*
1648          * in theory we could use lra on -RW media as well and just zero
1649          * blocks that haven't been written yet, but in practice that
1650          * is just a no-go. we'll use that for -R, naturally.
1651          */
1652         if (ti.lra_v) {
1653                 pd->lra = be32_to_cpu(ti.last_rec_address);
1654                 set_bit(PACKET_LRA_VALID, &pd->flags);
1655         } else {
1656                 pd->lra = 0xffffffff;
1657                 set_bit(PACKET_LRA_VALID, &pd->flags);
1658         }
1659
1660         /*
1661          * fine for now
1662          */
1663         pd->settings.link_loss = 7;
1664         pd->settings.write_type = 0;    /* packet */
1665         pd->settings.track_mode = ti.track_mode;
1666
1667         /*
1668          * mode1 or mode2 disc
1669          */
1670         switch (ti.data_mode) {
1671                 case PACKET_MODE1:
1672                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1673                         break;
1674                 case PACKET_MODE2:
1675                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1676                         break;
1677                 default:
1678                         printk("pktcdvd: unknown data mode\n");
1679                         return 1;
1680         }
1681         return 0;
1682 }
1683
1684 /*
1685  * enable/disable write caching on drive
1686  */
1687 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
1688 {
1689         struct packet_command cgc;
1690         struct request_sense sense;
1691         unsigned char buf[64];
1692         int ret;
1693
1694         memset(buf, 0, sizeof(buf));
1695         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1696         cgc.sense = &sense;
1697         cgc.buflen = pd->mode_offset + 12;
1698
1699         /*
1700          * caching mode page might not be there, so quiet this command
1701          */
1702         cgc.quiet = 1;
1703
1704         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1705                 return ret;
1706
1707         buf[pd->mode_offset + 10] |= (!!set << 2);
1708
1709         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1710         ret = pkt_mode_select(pd, &cgc);
1711         if (ret) {
1712                 printk("pktcdvd: write caching control failed\n");
1713                 pkt_dump_sense(&cgc);
1714         } else if (!ret && set)
1715                 printk("pktcdvd: enabled write caching on %s\n", pd->name);
1716         return ret;
1717 }
1718
1719 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1720 {
1721         struct packet_command cgc;
1722
1723         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1724         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1725         cgc.cmd[4] = lockflag ? 1 : 0;
1726         return pkt_generic_packet(pd, &cgc);
1727 }
1728
1729 /*
1730  * Returns drive maximum write speed
1731  */
1732 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
1733 {
1734         struct packet_command cgc;
1735         struct request_sense sense;
1736         unsigned char buf[256+18];
1737         unsigned char *cap_buf;
1738         int ret, offset;
1739
1740         memset(buf, 0, sizeof(buf));
1741         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1742         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1743         cgc.sense = &sense;
1744
1745         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1746         if (ret) {
1747                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1748                              sizeof(struct mode_page_header);
1749                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1750                 if (ret) {
1751                         pkt_dump_sense(&cgc);
1752                         return ret;
1753                 }
1754         }
1755
1756         offset = 20;                        /* Obsoleted field, used by older drives */
1757         if (cap_buf[1] >= 28)
1758                 offset = 28;                /* Current write speed selected */
1759         if (cap_buf[1] >= 30) {
1760                 /* If the drive reports at least one "Logical Unit Write
1761                  * Speed Performance Descriptor Block", use the information
1762                  * in the first block. (contains the highest speed)
1763                  */
1764                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1765                 if (num_spdb > 0)
1766                         offset = 34;
1767         }
1768
1769         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1770         return 0;
1771 }
1772
1773 /* These tables from cdrecord - I don't have orange book */
1774 /* standard speed CD-RW (1-4x) */
1775 static char clv_to_speed[16] = {
1776         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1777            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1778 };
1779 /* high speed CD-RW (-10x) */
1780 static char hs_clv_to_speed[16] = {
1781         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1782            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1783 };
1784 /* ultra high speed CD-RW */
1785 static char us_clv_to_speed[16] = {
1786         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1787            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1788 };
1789
1790 /*
1791  * reads the maximum media speed from ATIP
1792  */
1793 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
1794 {
1795         struct packet_command cgc;
1796         struct request_sense sense;
1797         unsigned char buf[64];
1798         unsigned int size, st, sp;
1799         int ret;
1800
1801         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1802         cgc.sense = &sense;
1803         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1804         cgc.cmd[1] = 2;
1805         cgc.cmd[2] = 4; /* READ ATIP */
1806         cgc.cmd[8] = 2;
1807         ret = pkt_generic_packet(pd, &cgc);
1808         if (ret) {
1809                 pkt_dump_sense(&cgc);
1810                 return ret;
1811         }
1812         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
1813         if (size > sizeof(buf))
1814                 size = sizeof(buf);
1815
1816         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
1817         cgc.sense = &sense;
1818         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1819         cgc.cmd[1] = 2;
1820         cgc.cmd[2] = 4;
1821         cgc.cmd[8] = size;
1822         ret = pkt_generic_packet(pd, &cgc);
1823         if (ret) {
1824                 pkt_dump_sense(&cgc);
1825                 return ret;
1826         }
1827
1828         if (!buf[6] & 0x40) {
1829                 printk("pktcdvd: Disc type is not CD-RW\n");
1830                 return 1;
1831         }
1832         if (!buf[6] & 0x4) {
1833                 printk("pktcdvd: A1 values on media are not valid, maybe not CDRW?\n");
1834                 return 1;
1835         }
1836
1837         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
1838
1839         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
1840
1841         /* Info from cdrecord */
1842         switch (st) {
1843                 case 0: /* standard speed */
1844                         *speed = clv_to_speed[sp];
1845                         break;
1846                 case 1: /* high speed */
1847                         *speed = hs_clv_to_speed[sp];
1848                         break;
1849                 case 2: /* ultra high speed */
1850                         *speed = us_clv_to_speed[sp];
1851                         break;
1852                 default:
1853                         printk("pktcdvd: Unknown disc sub-type %d\n",st);
1854                         return 1;
1855         }
1856         if (*speed) {
1857                 printk("pktcdvd: Max. media speed: %d\n",*speed);
1858                 return 0;
1859         } else {
1860                 printk("pktcdvd: Unknown speed %d for sub-type %d\n",sp,st);
1861                 return 1;
1862         }
1863 }
1864
1865 static int pkt_perform_opc(struct pktcdvd_device *pd)
1866 {
1867         struct packet_command cgc;
1868         struct request_sense sense;
1869         int ret;
1870
1871         VPRINTK("pktcdvd: Performing OPC\n");
1872
1873         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1874         cgc.sense = &sense;
1875         cgc.timeout = 60*HZ;
1876         cgc.cmd[0] = GPCMD_SEND_OPC;
1877         cgc.cmd[1] = 1;
1878         if ((ret = pkt_generic_packet(pd, &cgc)))
1879                 pkt_dump_sense(&cgc);
1880         return ret;
1881 }
1882
1883 static int pkt_open_write(struct pktcdvd_device *pd)
1884 {
1885         int ret;
1886         unsigned int write_speed, media_write_speed, read_speed;
1887
1888         if ((ret = pkt_probe_settings(pd))) {
1889                 DPRINTK("pktcdvd: %s failed probe\n", pd->name);
1890                 return -EIO;
1891         }
1892
1893         if ((ret = pkt_set_write_settings(pd))) {
1894                 DPRINTK("pktcdvd: %s failed saving write settings\n", pd->name);
1895                 return -EIO;
1896         }
1897
1898         pkt_write_caching(pd, USE_WCACHING);
1899
1900         if ((ret = pkt_get_max_speed(pd, &write_speed)))
1901                 write_speed = 16 * 177;
1902         switch (pd->mmc3_profile) {
1903                 case 0x13: /* DVD-RW */
1904                 case 0x1a: /* DVD+RW */
1905                 case 0x12: /* DVD-RAM */
1906                         DPRINTK("pktcdvd: write speed %ukB/s\n", write_speed);
1907                         break;
1908                 default:
1909                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
1910                                 media_write_speed = 16;
1911                         write_speed = min(write_speed, media_write_speed * 177);
1912                         DPRINTK("pktcdvd: write speed %ux\n", write_speed / 176);
1913                         break;
1914         }
1915         read_speed = write_speed;
1916
1917         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
1918                 DPRINTK("pktcdvd: %s couldn't set write speed\n", pd->name);
1919                 return -EIO;
1920         }
1921         pd->write_speed = write_speed;
1922         pd->read_speed = read_speed;
1923
1924         if ((ret = pkt_perform_opc(pd))) {
1925                 DPRINTK("pktcdvd: %s Optimum Power Calibration failed\n", pd->name);
1926         }
1927
1928         return 0;
1929 }
1930
1931 /*
1932  * called at open time.
1933  */
1934 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
1935 {
1936         int ret;
1937         long lba;
1938         request_queue_t *q;
1939
1940         /*
1941          * We need to re-open the cdrom device without O_NONBLOCK to be able
1942          * to read/write from/to it. It is already opened in O_NONBLOCK mode
1943          * so bdget() can't fail.
1944          */
1945         bdget(pd->bdev->bd_dev);
1946         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
1947                 goto out;
1948
1949         if ((ret = pkt_get_last_written(pd, &lba))) {
1950                 printk("pktcdvd: pkt_get_last_written failed\n");
1951                 goto out_putdev;
1952         }
1953
1954         set_capacity(pd->disk, lba << 2);
1955         set_capacity(pd->bdev->bd_disk, lba << 2);
1956         bd_set_size(pd->bdev, (loff_t)lba << 11);
1957
1958         q = bdev_get_queue(pd->bdev);
1959         if (write) {
1960                 if ((ret = pkt_open_write(pd)))
1961                         goto out_putdev;
1962                 /*
1963                  * Some CDRW drives can not handle writes larger than one packet,
1964                  * even if the size is a multiple of the packet size.
1965                  */
1966                 spin_lock_irq(q->queue_lock);
1967                 blk_queue_max_sectors(q, pd->settings.size);
1968                 spin_unlock_irq(q->queue_lock);
1969                 set_bit(PACKET_WRITABLE, &pd->flags);
1970         } else {
1971                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
1972                 clear_bit(PACKET_WRITABLE, &pd->flags);
1973         }
1974
1975         if ((ret = pkt_set_segment_merging(pd, q)))
1976                 goto out_putdev;
1977
1978         if (write)
1979                 printk("pktcdvd: %lukB available on disc\n", lba << 1);
1980
1981         return 0;
1982
1983 out_putdev:
1984         blkdev_put(pd->bdev);
1985 out:
1986         return ret;
1987 }
1988
1989 /*
1990  * called when the device is closed. makes sure that the device flushes
1991  * the internal cache before we close.
1992  */
1993 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
1994 {
1995         if (flush && pkt_flush_cache(pd))
1996                 DPRINTK("pktcdvd: %s not flushing cache\n", pd->name);
1997
1998         pkt_lock_door(pd, 0);
1999
2000         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2001         blkdev_put(pd->bdev);
2002 }
2003
2004 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2005 {
2006         if (dev_minor >= MAX_WRITERS)
2007                 return NULL;
2008         return pkt_devs[dev_minor];
2009 }
2010
2011 static int pkt_open(struct inode *inode, struct file *file)
2012 {
2013         struct pktcdvd_device *pd = NULL;
2014         int ret;
2015
2016         VPRINTK("pktcdvd: entering open\n");
2017
2018         down(&ctl_mutex);
2019         pd = pkt_find_dev_from_minor(iminor(inode));
2020         if (!pd) {
2021                 ret = -ENODEV;
2022                 goto out;
2023         }
2024         BUG_ON(pd->refcnt < 0);
2025
2026         pd->refcnt++;
2027         if (pd->refcnt > 1) {
2028                 if ((file->f_mode & FMODE_WRITE) &&
2029                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2030                         ret = -EBUSY;
2031                         goto out_dec;
2032                 }
2033         } else {
2034                 if (pkt_open_dev(pd, file->f_mode & FMODE_WRITE)) {
2035                         ret = -EIO;
2036                         goto out_dec;
2037                 }
2038                 /*
2039                  * needed here as well, since ext2 (among others) may change
2040                  * the blocksize at mount time
2041                  */
2042                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2043         }
2044
2045         up(&ctl_mutex);
2046         return 0;
2047
2048 out_dec:
2049         pd->refcnt--;
2050 out:
2051         VPRINTK("pktcdvd: failed open (%d)\n", ret);
2052         up(&ctl_mutex);
2053         return ret;
2054 }
2055
2056 static int pkt_close(struct inode *inode, struct file *file)
2057 {
2058         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2059         int ret = 0;
2060
2061         down(&ctl_mutex);
2062         pd->refcnt--;
2063         BUG_ON(pd->refcnt < 0);
2064         if (pd->refcnt == 0) {
2065                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2066                 pkt_release_dev(pd, flush);
2067         }
2068         up(&ctl_mutex);
2069         return ret;
2070 }
2071
2072
2073 static void *psd_pool_alloc(unsigned int __nocast gfp_mask, void *data)
2074 {
2075         return kmalloc(sizeof(struct packet_stacked_data), gfp_mask);
2076 }
2077
2078 static void psd_pool_free(void *ptr, void *data)
2079 {
2080         kfree(ptr);
2081 }
2082
2083 static int pkt_end_io_read_cloned(struct bio *bio, unsigned int bytes_done, int err)
2084 {
2085         struct packet_stacked_data *psd = bio->bi_private;
2086         struct pktcdvd_device *pd = psd->pd;
2087
2088         if (bio->bi_size)
2089                 return 1;
2090
2091         bio_put(bio);
2092         bio_endio(psd->bio, psd->bio->bi_size, err);
2093         mempool_free(psd, psd_pool);
2094         pkt_bio_finished(pd);
2095         return 0;
2096 }
2097
2098 static int pkt_make_request(request_queue_t *q, struct bio *bio)
2099 {
2100         struct pktcdvd_device *pd;
2101         char b[BDEVNAME_SIZE];
2102         sector_t zone;
2103         struct packet_data *pkt;
2104         int was_empty, blocked_bio;
2105         struct pkt_rb_node *node;
2106
2107         pd = q->queuedata;
2108         if (!pd) {
2109                 printk("pktcdvd: %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2110                 goto end_io;
2111         }
2112
2113         /*
2114          * Clone READ bios so we can have our own bi_end_io callback.
2115          */
2116         if (bio_data_dir(bio) == READ) {
2117                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2118                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2119
2120                 psd->pd = pd;
2121                 psd->bio = bio;
2122                 cloned_bio->bi_bdev = pd->bdev;
2123                 cloned_bio->bi_private = psd;
2124                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2125                 pd->stats.secs_r += bio->bi_size >> 9;
2126                 pkt_queue_bio(pd, cloned_bio);
2127                 return 0;
2128         }
2129
2130         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2131                 printk("pktcdvd: WRITE for ro device %s (%llu)\n",
2132                         pd->name, (unsigned long long)bio->bi_sector);
2133                 goto end_io;
2134         }
2135
2136         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2137                 printk("pktcdvd: wrong bio size\n");
2138                 goto end_io;
2139         }
2140
2141         blk_queue_bounce(q, &bio);
2142
2143         zone = ZONE(bio->bi_sector, pd);
2144         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2145                 (unsigned long long)bio->bi_sector,
2146                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2147
2148         /* Check if we have to split the bio */
2149         {
2150                 struct bio_pair *bp;
2151                 sector_t last_zone;
2152                 int first_sectors;
2153
2154                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2155                 if (last_zone != zone) {
2156                         BUG_ON(last_zone != zone + pd->settings.size);
2157                         first_sectors = last_zone - bio->bi_sector;
2158                         bp = bio_split(bio, bio_split_pool, first_sectors);
2159                         BUG_ON(!bp);
2160                         pkt_make_request(q, &bp->bio1);
2161                         pkt_make_request(q, &bp->bio2);
2162                         bio_pair_release(bp);
2163                         return 0;
2164                 }
2165         }
2166
2167         /*
2168          * If we find a matching packet in state WAITING or READ_WAIT, we can
2169          * just append this bio to that packet.
2170          */
2171         spin_lock(&pd->cdrw.active_list_lock);
2172         blocked_bio = 0;
2173         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2174                 if (pkt->sector == zone) {
2175                         spin_lock(&pkt->lock);
2176                         if ((pkt->state == PACKET_WAITING_STATE) ||
2177                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2178                                 pkt_add_list_last(bio, &pkt->orig_bios,
2179                                                   &pkt->orig_bios_tail);
2180                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2181                                 if ((pkt->write_size >= pkt->frames) &&
2182                                     (pkt->state == PACKET_WAITING_STATE)) {
2183                                         atomic_inc(&pkt->run_sm);
2184                                         wake_up(&pd->wqueue);
2185                                 }
2186                                 spin_unlock(&pkt->lock);
2187                                 spin_unlock(&pd->cdrw.active_list_lock);
2188                                 return 0;
2189                         } else {
2190                                 blocked_bio = 1;
2191                         }
2192                         spin_unlock(&pkt->lock);
2193                 }
2194         }
2195         spin_unlock(&pd->cdrw.active_list_lock);
2196
2197         /*
2198          * No matching packet found. Store the bio in the work queue.
2199          */
2200         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2201         BUG_ON(!node);
2202         node->bio = bio;
2203         spin_lock(&pd->lock);
2204         BUG_ON(pd->bio_queue_size < 0);
2205         was_empty = (pd->bio_queue_size == 0);
2206         pkt_rbtree_insert(pd, node);
2207         spin_unlock(&pd->lock);
2208
2209         /*
2210          * Wake up the worker thread.
2211          */
2212         atomic_set(&pd->scan_queue, 1);
2213         if (was_empty) {
2214                 /* This wake_up is required for correct operation */
2215                 wake_up(&pd->wqueue);
2216         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2217                 /*
2218                  * This wake up is not required for correct operation,
2219                  * but improves performance in some cases.
2220                  */
2221                 wake_up(&pd->wqueue);
2222         }
2223         return 0;
2224 end_io:
2225         bio_io_error(bio, bio->bi_size);
2226         return 0;
2227 }
2228
2229
2230
2231 static int pkt_merge_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *bvec)
2232 {
2233         struct pktcdvd_device *pd = q->queuedata;
2234         sector_t zone = ZONE(bio->bi_sector, pd);
2235         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2236         int remaining = (pd->settings.size << 9) - used;
2237         int remaining2;
2238
2239         /*
2240          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2241          * boundary, pkt_make_request() will split the bio.
2242          */
2243         remaining2 = PAGE_SIZE - bio->bi_size;
2244         remaining = max(remaining, remaining2);
2245
2246         BUG_ON(remaining < 0);
2247         return remaining;
2248 }
2249
2250 static void pkt_init_queue(struct pktcdvd_device *pd)
2251 {
2252         request_queue_t *q = pd->disk->queue;
2253
2254         blk_queue_make_request(q, pkt_make_request);
2255         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2256         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2257         blk_queue_merge_bvec(q, pkt_merge_bvec);
2258         q->queuedata = pd;
2259 }
2260
2261 static int pkt_seq_show(struct seq_file *m, void *p)
2262 {
2263         struct pktcdvd_device *pd = m->private;
2264         char *msg;
2265         char bdev_buf[BDEVNAME_SIZE];
2266         int states[PACKET_NUM_STATES];
2267
2268         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2269                    bdevname(pd->bdev, bdev_buf));
2270
2271         seq_printf(m, "\nSettings:\n");
2272         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2273
2274         if (pd->settings.write_type == 0)
2275                 msg = "Packet";
2276         else
2277                 msg = "Unknown";
2278         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2279
2280         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2281         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2282
2283         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2284
2285         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2286                 msg = "Mode 1";
2287         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2288                 msg = "Mode 2";
2289         else
2290                 msg = "Unknown";
2291         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2292
2293         seq_printf(m, "\nStatistics:\n");
2294         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2295         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2296         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2297         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2298         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2299
2300         seq_printf(m, "\nMisc:\n");
2301         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2302         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2303         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2304         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2305         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2306         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2307
2308         seq_printf(m, "\nQueue state:\n");
2309         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2310         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2311         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2312
2313         pkt_count_states(pd, states);
2314         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2315                    states[0], states[1], states[2], states[3], states[4], states[5]);
2316
2317         return 0;
2318 }
2319
2320 static int pkt_seq_open(struct inode *inode, struct file *file)
2321 {
2322         return single_open(file, pkt_seq_show, PDE(inode)->data);
2323 }
2324
2325 static struct file_operations pkt_proc_fops = {
2326         .open   = pkt_seq_open,
2327         .read   = seq_read,
2328         .llseek = seq_lseek,
2329         .release = single_release
2330 };
2331
2332 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2333 {
2334         int i;
2335         int ret = 0;
2336         char b[BDEVNAME_SIZE];
2337         struct proc_dir_entry *proc;
2338         struct block_device *bdev;
2339
2340         if (pd->pkt_dev == dev) {
2341                 printk("pktcdvd: Recursive setup not allowed\n");
2342                 return -EBUSY;
2343         }
2344         for (i = 0; i < MAX_WRITERS; i++) {
2345                 struct pktcdvd_device *pd2 = pkt_devs[i];
2346                 if (!pd2)
2347                         continue;
2348                 if (pd2->bdev->bd_dev == dev) {
2349                         printk("pktcdvd: %s already setup\n", bdevname(pd2->bdev, b));
2350                         return -EBUSY;
2351                 }
2352                 if (pd2->pkt_dev == dev) {
2353                         printk("pktcdvd: Can't chain pktcdvd devices\n");
2354                         return -EBUSY;
2355                 }
2356         }
2357
2358         bdev = bdget(dev);
2359         if (!bdev)
2360                 return -ENOMEM;
2361         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2362         if (ret)
2363                 return ret;
2364
2365         /* This is safe, since we have a reference from open(). */
2366         __module_get(THIS_MODULE);
2367
2368         if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2369                 printk("pktcdvd: not enough memory for buffers\n");
2370                 ret = -ENOMEM;
2371                 goto out_mem;
2372         }
2373
2374         pd->bdev = bdev;
2375         set_blocksize(bdev, CD_FRAMESIZE);
2376
2377         pkt_init_queue(pd);
2378
2379         atomic_set(&pd->cdrw.pending_bios, 0);
2380         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2381         if (IS_ERR(pd->cdrw.thread)) {
2382                 printk("pktcdvd: can't start kernel thread\n");
2383                 ret = -ENOMEM;
2384                 goto out_thread;
2385         }
2386
2387         proc = create_proc_entry(pd->name, 0, pkt_proc);
2388         if (proc) {
2389                 proc->data = pd;
2390                 proc->proc_fops = &pkt_proc_fops;
2391         }
2392         DPRINTK("pktcdvd: writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2393         return 0;
2394
2395 out_thread:
2396         pkt_shrink_pktlist(pd);
2397 out_mem:
2398         blkdev_put(bdev);
2399         /* This is safe: open() is still holding a reference. */
2400         module_put(THIS_MODULE);
2401         return ret;
2402 }
2403
2404 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2405 {
2406         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2407
2408         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2409         BUG_ON(!pd);
2410
2411         switch (cmd) {
2412         /*
2413          * forward selected CDROM ioctls to CD-ROM, for UDF
2414          */
2415         case CDROMMULTISESSION:
2416         case CDROMREADTOCENTRY:
2417         case CDROM_LAST_WRITTEN:
2418         case CDROM_SEND_PACKET:
2419         case SCSI_IOCTL_SEND_COMMAND:
2420                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2421
2422         case CDROMEJECT:
2423                 /*
2424                  * The door gets locked when the device is opened, so we
2425                  * have to unlock it or else the eject command fails.
2426                  */
2427                 pkt_lock_door(pd, 0);
2428                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2429
2430         default:
2431                 printk("pktcdvd: Unknown ioctl for %s (%x)\n", pd->name, cmd);
2432                 return -ENOTTY;
2433         }
2434
2435         return 0;
2436 }
2437
2438 static int pkt_media_changed(struct gendisk *disk)
2439 {
2440         struct pktcdvd_device *pd = disk->private_data;
2441         struct gendisk *attached_disk;
2442
2443         if (!pd)
2444                 return 0;
2445         if (!pd->bdev)
2446                 return 0;
2447         attached_disk = pd->bdev->bd_disk;
2448         if (!attached_disk)
2449                 return 0;
2450         return attached_disk->fops->media_changed(attached_disk);
2451 }
2452
2453 static struct block_device_operations pktcdvd_ops = {
2454         .owner =                THIS_MODULE,
2455         .open =                 pkt_open,
2456         .release =              pkt_close,
2457         .ioctl =                pkt_ioctl,
2458         .media_changed =        pkt_media_changed,
2459 };
2460
2461 /*
2462  * Set up mapping from pktcdvd device to CD-ROM device.
2463  */
2464 static int pkt_setup_dev(struct pkt_ctrl_command *ctrl_cmd)
2465 {
2466         int idx;
2467         int ret = -ENOMEM;
2468         struct pktcdvd_device *pd;
2469         struct gendisk *disk;
2470         dev_t dev = new_decode_dev(ctrl_cmd->dev);
2471
2472         for (idx = 0; idx < MAX_WRITERS; idx++)
2473                 if (!pkt_devs[idx])
2474                         break;
2475         if (idx == MAX_WRITERS) {
2476                 printk("pktcdvd: max %d writers supported\n", MAX_WRITERS);
2477                 return -EBUSY;
2478         }
2479
2480         pd = kmalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2481         if (!pd)
2482                 return ret;
2483         memset(pd, 0, sizeof(struct pktcdvd_device));
2484
2485         pd->rb_pool = mempool_create(PKT_RB_POOL_SIZE, pkt_rb_alloc, pkt_rb_free, NULL);
2486         if (!pd->rb_pool)
2487                 goto out_mem;
2488
2489         disk = alloc_disk(1);
2490         if (!disk)
2491                 goto out_mem;
2492         pd->disk = disk;
2493
2494         spin_lock_init(&pd->lock);
2495         spin_lock_init(&pd->iosched.lock);
2496         sprintf(pd->name, "pktcdvd%d", idx);
2497         init_waitqueue_head(&pd->wqueue);
2498         pd->bio_queue = RB_ROOT;
2499
2500         disk->major = pkt_major;
2501         disk->first_minor = idx;
2502         disk->fops = &pktcdvd_ops;
2503         disk->flags = GENHD_FL_REMOVABLE;
2504         sprintf(disk->disk_name, "pktcdvd%d", idx);
2505         disk->private_data = pd;
2506         disk->queue = blk_alloc_queue(GFP_KERNEL);
2507         if (!disk->queue)
2508                 goto out_mem2;
2509
2510         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2511         ret = pkt_new_dev(pd, dev);
2512         if (ret)
2513                 goto out_new_dev;
2514
2515         add_disk(disk);
2516         pkt_devs[idx] = pd;
2517         ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2518         return 0;
2519
2520 out_new_dev:
2521         blk_put_queue(disk->queue);
2522 out_mem2:
2523         put_disk(disk);
2524 out_mem:
2525         if (pd->rb_pool)
2526                 mempool_destroy(pd->rb_pool);
2527         kfree(pd);
2528         return ret;
2529 }
2530
2531 /*
2532  * Tear down mapping from pktcdvd device to CD-ROM device.
2533  */
2534 static int pkt_remove_dev(struct pkt_ctrl_command *ctrl_cmd)
2535 {
2536         struct pktcdvd_device *pd;
2537         int idx;
2538         dev_t pkt_dev = new_decode_dev(ctrl_cmd->pkt_dev);
2539
2540         for (idx = 0; idx < MAX_WRITERS; idx++) {
2541                 pd = pkt_devs[idx];
2542                 if (pd && (pd->pkt_dev == pkt_dev))
2543                         break;
2544         }
2545         if (idx == MAX_WRITERS) {
2546                 DPRINTK("pktcdvd: dev not setup\n");
2547                 return -ENXIO;
2548         }
2549
2550         if (pd->refcnt > 0)
2551                 return -EBUSY;
2552
2553         if (!IS_ERR(pd->cdrw.thread))
2554                 kthread_stop(pd->cdrw.thread);
2555
2556         blkdev_put(pd->bdev);
2557
2558         pkt_shrink_pktlist(pd);
2559
2560         remove_proc_entry(pd->name, pkt_proc);
2561         DPRINTK("pktcdvd: writer %s unmapped\n", pd->name);
2562
2563         del_gendisk(pd->disk);
2564         blk_put_queue(pd->disk->queue);
2565         put_disk(pd->disk);
2566
2567         pkt_devs[idx] = NULL;
2568         mempool_destroy(pd->rb_pool);
2569         kfree(pd);
2570
2571         /* This is safe: open() is still holding a reference. */
2572         module_put(THIS_MODULE);
2573         return 0;
2574 }
2575
2576 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2577 {
2578         struct pktcdvd_device *pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2579         if (pd) {
2580                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2581                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2582         } else {
2583                 ctrl_cmd->dev = 0;
2584                 ctrl_cmd->pkt_dev = 0;
2585         }
2586         ctrl_cmd->num_devices = MAX_WRITERS;
2587 }
2588
2589 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2590 {
2591         void __user *argp = (void __user *)arg;
2592         struct pkt_ctrl_command ctrl_cmd;
2593         int ret = 0;
2594
2595         if (cmd != PACKET_CTRL_CMD)
2596                 return -ENOTTY;
2597
2598         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2599                 return -EFAULT;
2600
2601         switch (ctrl_cmd.command) {
2602         case PKT_CTRL_CMD_SETUP:
2603                 if (!capable(CAP_SYS_ADMIN))
2604                         return -EPERM;
2605                 down(&ctl_mutex);
2606                 ret = pkt_setup_dev(&ctrl_cmd);
2607                 up(&ctl_mutex);
2608                 break;
2609         case PKT_CTRL_CMD_TEARDOWN:
2610                 if (!capable(CAP_SYS_ADMIN))
2611                         return -EPERM;
2612                 down(&ctl_mutex);
2613                 ret = pkt_remove_dev(&ctrl_cmd);
2614                 up(&ctl_mutex);
2615                 break;
2616         case PKT_CTRL_CMD_STATUS:
2617                 down(&ctl_mutex);
2618                 pkt_get_status(&ctrl_cmd);
2619                 up(&ctl_mutex);
2620                 break;
2621         default:
2622                 return -ENOTTY;
2623         }
2624
2625         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2626                 return -EFAULT;
2627         return ret;
2628 }
2629
2630
2631 static struct file_operations pkt_ctl_fops = {
2632         .ioctl   = pkt_ctl_ioctl,
2633         .owner   = THIS_MODULE,
2634 };
2635
2636 static struct miscdevice pkt_misc = {
2637         .minor          = MISC_DYNAMIC_MINOR,
2638         .name           = "pktcdvd",
2639         .devfs_name     = "pktcdvd/control",
2640         .fops           = &pkt_ctl_fops
2641 };
2642
2643 static int __init pkt_init(void)
2644 {
2645         int ret;
2646
2647         psd_pool = mempool_create(PSD_POOL_SIZE, psd_pool_alloc, psd_pool_free, NULL);
2648         if (!psd_pool)
2649                 return -ENOMEM;
2650
2651         ret = register_blkdev(pkt_major, "pktcdvd");
2652         if (ret < 0) {
2653                 printk("pktcdvd: Unable to register block device\n");
2654                 goto out2;
2655         }
2656         if (!pkt_major)
2657                 pkt_major = ret;
2658
2659         ret = misc_register(&pkt_misc);
2660         if (ret) {
2661                 printk("pktcdvd: Unable to register misc device\n");
2662                 goto out;
2663         }
2664
2665         init_MUTEX(&ctl_mutex);
2666
2667         pkt_proc = proc_mkdir("pktcdvd", proc_root_driver);
2668
2669         DPRINTK("pktcdvd: %s\n", VERSION_CODE);
2670         return 0;
2671
2672 out:
2673         unregister_blkdev(pkt_major, "pktcdvd");
2674 out2:
2675         mempool_destroy(psd_pool);
2676         return ret;
2677 }
2678
2679 static void __exit pkt_exit(void)
2680 {
2681         remove_proc_entry("pktcdvd", proc_root_driver);
2682         misc_deregister(&pkt_misc);
2683         unregister_blkdev(pkt_major, "pktcdvd");
2684         mempool_destroy(psd_pool);
2685 }
2686
2687 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2688 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2689 MODULE_LICENSE("GPL");
2690
2691 module_init(pkt_init);
2692 module_exit(pkt_exit);