Merge remote-tracking branch 'lsk/v3.10/topic/gator' into linux-linaro-lsk
[firefly-linux-kernel-4.4.55.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  * Copyright (C) 2006 Thomas Maier <balagi@justmail.de>
5  *
6  * May be copied or modified under the terms of the GNU General Public
7  * License.  See linux/COPYING for more information.
8  *
9  * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
10  * DVD-RAM devices.
11  *
12  * Theory of operation:
13  *
14  * At the lowest level, there is the standard driver for the CD/DVD device,
15  * typically ide-cd.c or sr.c. This driver can handle read and write requests,
16  * but it doesn't know anything about the special restrictions that apply to
17  * packet writing. One restriction is that write requests must be aligned to
18  * packet boundaries on the physical media, and the size of a write request
19  * must be equal to the packet size. Another restriction is that a
20  * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
21  * command, if the previous command was a write.
22  *
23  * The purpose of the packet writing driver is to hide these restrictions from
24  * higher layers, such as file systems, and present a block device that can be
25  * randomly read and written using 2kB-sized blocks.
26  *
27  * The lowest layer in the packet writing driver is the packet I/O scheduler.
28  * Its data is defined by the struct packet_iosched and includes two bio
29  * queues with pending read and write requests. These queues are processed
30  * by the pkt_iosched_process_queue() function. The write requests in this
31  * queue are already properly aligned and sized. This layer is responsible for
32  * issuing the flush cache commands and scheduling the I/O in a good order.
33  *
34  * The next layer transforms unaligned write requests to aligned writes. This
35  * transformation requires reading missing pieces of data from the underlying
36  * block device, assembling the pieces to full packets and queuing them to the
37  * packet I/O scheduler.
38  *
39  * At the top layer there is a custom make_request_fn function that forwards
40  * read requests directly to the iosched queue and puts write requests in the
41  * unaligned write queue. A kernel thread performs the necessary read
42  * gathering to convert the unaligned writes to aligned writes and then feeds
43  * them to the packet I/O scheduler.
44  *
45  *************************************************************************/
46
47 #include <linux/pktcdvd.h>
48 #include <linux/module.h>
49 #include <linux/types.h>
50 #include <linux/kernel.h>
51 #include <linux/compat.h>
52 #include <linux/kthread.h>
53 #include <linux/errno.h>
54 #include <linux/spinlock.h>
55 #include <linux/file.h>
56 #include <linux/proc_fs.h>
57 #include <linux/seq_file.h>
58 #include <linux/miscdevice.h>
59 #include <linux/freezer.h>
60 #include <linux/mutex.h>
61 #include <linux/slab.h>
62 #include <scsi/scsi_cmnd.h>
63 #include <scsi/scsi_ioctl.h>
64 #include <scsi/scsi.h>
65 #include <linux/debugfs.h>
66 #include <linux/device.h>
67
68 #include <asm/uaccess.h>
69
70 #define DRIVER_NAME     "pktcdvd"
71
72 #if PACKET_DEBUG
73 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
74 #else
75 #define DPRINTK(fmt, args...)
76 #endif
77
78 #if PACKET_DEBUG > 1
79 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
80 #else
81 #define VPRINTK(fmt, args...)
82 #endif
83
84 #define MAX_SPEED 0xffff
85
86 #define ZONE(sector, pd) (((sector) + (pd)->offset) & \
87                         ~(sector_t)((pd)->settings.size - 1))
88
89 static DEFINE_MUTEX(pktcdvd_mutex);
90 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
91 static struct proc_dir_entry *pkt_proc;
92 static int pktdev_major;
93 static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
94 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
95 static struct mutex ctl_mutex;  /* Serialize open/close/setup/teardown */
96 static mempool_t *psd_pool;
97
98 static struct class     *class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
99 static struct dentry    *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
100
101 /* forward declaration */
102 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
103 static int pkt_remove_dev(dev_t pkt_dev);
104 static int pkt_seq_show(struct seq_file *m, void *p);
105
106
107
108 /*
109  * create and register a pktcdvd kernel object.
110  */
111 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
112                                         const char* name,
113                                         struct kobject* parent,
114                                         struct kobj_type* ktype)
115 {
116         struct pktcdvd_kobj *p;
117         int error;
118
119         p = kzalloc(sizeof(*p), GFP_KERNEL);
120         if (!p)
121                 return NULL;
122         p->pd = pd;
123         error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
124         if (error) {
125                 kobject_put(&p->kobj);
126                 return NULL;
127         }
128         kobject_uevent(&p->kobj, KOBJ_ADD);
129         return p;
130 }
131 /*
132  * remove a pktcdvd kernel object.
133  */
134 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
135 {
136         if (p)
137                 kobject_put(&p->kobj);
138 }
139 /*
140  * default release function for pktcdvd kernel objects.
141  */
142 static void pkt_kobj_release(struct kobject *kobj)
143 {
144         kfree(to_pktcdvdkobj(kobj));
145 }
146
147
148 /**********************************************************
149  *
150  * sysfs interface for pktcdvd
151  * by (C) 2006  Thomas Maier <balagi@justmail.de>
152  *
153  **********************************************************/
154
155 #define DEF_ATTR(_obj,_name,_mode) \
156         static struct attribute _obj = { .name = _name, .mode = _mode }
157
158 /**********************************************************
159   /sys/class/pktcdvd/pktcdvd[0-7]/
160                      stat/reset
161                      stat/packets_started
162                      stat/packets_finished
163                      stat/kb_written
164                      stat/kb_read
165                      stat/kb_read_gather
166                      write_queue/size
167                      write_queue/congestion_off
168                      write_queue/congestion_on
169  **********************************************************/
170
171 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
172 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
173 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
174 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
175 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
176 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
177
178 static struct attribute *kobj_pkt_attrs_stat[] = {
179         &kobj_pkt_attr_st1,
180         &kobj_pkt_attr_st2,
181         &kobj_pkt_attr_st3,
182         &kobj_pkt_attr_st4,
183         &kobj_pkt_attr_st5,
184         &kobj_pkt_attr_st6,
185         NULL
186 };
187
188 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
189 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
190 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
191
192 static struct attribute *kobj_pkt_attrs_wqueue[] = {
193         &kobj_pkt_attr_wq1,
194         &kobj_pkt_attr_wq2,
195         &kobj_pkt_attr_wq3,
196         NULL
197 };
198
199 static ssize_t kobj_pkt_show(struct kobject *kobj,
200                         struct attribute *attr, char *data)
201 {
202         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
203         int n = 0;
204         int v;
205         if (strcmp(attr->name, "packets_started") == 0) {
206                 n = sprintf(data, "%lu\n", pd->stats.pkt_started);
207
208         } else if (strcmp(attr->name, "packets_finished") == 0) {
209                 n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
210
211         } else if (strcmp(attr->name, "kb_written") == 0) {
212                 n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
213
214         } else if (strcmp(attr->name, "kb_read") == 0) {
215                 n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
216
217         } else if (strcmp(attr->name, "kb_read_gather") == 0) {
218                 n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
219
220         } else if (strcmp(attr->name, "size") == 0) {
221                 spin_lock(&pd->lock);
222                 v = pd->bio_queue_size;
223                 spin_unlock(&pd->lock);
224                 n = sprintf(data, "%d\n", v);
225
226         } else if (strcmp(attr->name, "congestion_off") == 0) {
227                 spin_lock(&pd->lock);
228                 v = pd->write_congestion_off;
229                 spin_unlock(&pd->lock);
230                 n = sprintf(data, "%d\n", v);
231
232         } else if (strcmp(attr->name, "congestion_on") == 0) {
233                 spin_lock(&pd->lock);
234                 v = pd->write_congestion_on;
235                 spin_unlock(&pd->lock);
236                 n = sprintf(data, "%d\n", v);
237         }
238         return n;
239 }
240
241 static void init_write_congestion_marks(int* lo, int* hi)
242 {
243         if (*hi > 0) {
244                 *hi = max(*hi, 500);
245                 *hi = min(*hi, 1000000);
246                 if (*lo <= 0)
247                         *lo = *hi - 100;
248                 else {
249                         *lo = min(*lo, *hi - 100);
250                         *lo = max(*lo, 100);
251                 }
252         } else {
253                 *hi = -1;
254                 *lo = -1;
255         }
256 }
257
258 static ssize_t kobj_pkt_store(struct kobject *kobj,
259                         struct attribute *attr,
260                         const char *data, size_t len)
261 {
262         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
263         int val;
264
265         if (strcmp(attr->name, "reset") == 0 && len > 0) {
266                 pd->stats.pkt_started = 0;
267                 pd->stats.pkt_ended = 0;
268                 pd->stats.secs_w = 0;
269                 pd->stats.secs_rg = 0;
270                 pd->stats.secs_r = 0;
271
272         } else if (strcmp(attr->name, "congestion_off") == 0
273                    && sscanf(data, "%d", &val) == 1) {
274                 spin_lock(&pd->lock);
275                 pd->write_congestion_off = val;
276                 init_write_congestion_marks(&pd->write_congestion_off,
277                                         &pd->write_congestion_on);
278                 spin_unlock(&pd->lock);
279
280         } else if (strcmp(attr->name, "congestion_on") == 0
281                    && sscanf(data, "%d", &val) == 1) {
282                 spin_lock(&pd->lock);
283                 pd->write_congestion_on = val;
284                 init_write_congestion_marks(&pd->write_congestion_off,
285                                         &pd->write_congestion_on);
286                 spin_unlock(&pd->lock);
287         }
288         return len;
289 }
290
291 static const struct sysfs_ops kobj_pkt_ops = {
292         .show = kobj_pkt_show,
293         .store = kobj_pkt_store
294 };
295 static struct kobj_type kobj_pkt_type_stat = {
296         .release = pkt_kobj_release,
297         .sysfs_ops = &kobj_pkt_ops,
298         .default_attrs = kobj_pkt_attrs_stat
299 };
300 static struct kobj_type kobj_pkt_type_wqueue = {
301         .release = pkt_kobj_release,
302         .sysfs_ops = &kobj_pkt_ops,
303         .default_attrs = kobj_pkt_attrs_wqueue
304 };
305
306 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
307 {
308         if (class_pktcdvd) {
309                 pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
310                                         "%s", pd->name);
311                 if (IS_ERR(pd->dev))
312                         pd->dev = NULL;
313         }
314         if (pd->dev) {
315                 pd->kobj_stat = pkt_kobj_create(pd, "stat",
316                                         &pd->dev->kobj,
317                                         &kobj_pkt_type_stat);
318                 pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
319                                         &pd->dev->kobj,
320                                         &kobj_pkt_type_wqueue);
321         }
322 }
323
324 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
325 {
326         pkt_kobj_remove(pd->kobj_stat);
327         pkt_kobj_remove(pd->kobj_wqueue);
328         if (class_pktcdvd)
329                 device_unregister(pd->dev);
330 }
331
332
333 /********************************************************************
334   /sys/class/pktcdvd/
335                      add            map block device
336                      remove         unmap packet dev
337                      device_map     show mappings
338  *******************************************************************/
339
340 static void class_pktcdvd_release(struct class *cls)
341 {
342         kfree(cls);
343 }
344 static ssize_t class_pktcdvd_show_map(struct class *c,
345                                         struct class_attribute *attr,
346                                         char *data)
347 {
348         int n = 0;
349         int idx;
350         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
351         for (idx = 0; idx < MAX_WRITERS; idx++) {
352                 struct pktcdvd_device *pd = pkt_devs[idx];
353                 if (!pd)
354                         continue;
355                 n += sprintf(data+n, "%s %u:%u %u:%u\n",
356                         pd->name,
357                         MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
358                         MAJOR(pd->bdev->bd_dev),
359                         MINOR(pd->bdev->bd_dev));
360         }
361         mutex_unlock(&ctl_mutex);
362         return n;
363 }
364
365 static ssize_t class_pktcdvd_store_add(struct class *c,
366                                         struct class_attribute *attr,
367                                         const char *buf,
368                                         size_t count)
369 {
370         unsigned int major, minor;
371
372         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
373                 /* pkt_setup_dev() expects caller to hold reference to self */
374                 if (!try_module_get(THIS_MODULE))
375                         return -ENODEV;
376
377                 pkt_setup_dev(MKDEV(major, minor), NULL);
378
379                 module_put(THIS_MODULE);
380
381                 return count;
382         }
383
384         return -EINVAL;
385 }
386
387 static ssize_t class_pktcdvd_store_remove(struct class *c,
388                                           struct class_attribute *attr,
389                                           const char *buf,
390                                         size_t count)
391 {
392         unsigned int major, minor;
393         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
394                 pkt_remove_dev(MKDEV(major, minor));
395                 return count;
396         }
397         return -EINVAL;
398 }
399
400 static struct class_attribute class_pktcdvd_attrs[] = {
401  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
402  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
403  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
404  __ATTR_NULL
405 };
406
407
408 static int pkt_sysfs_init(void)
409 {
410         int ret = 0;
411
412         /*
413          * create control files in sysfs
414          * /sys/class/pktcdvd/...
415          */
416         class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
417         if (!class_pktcdvd)
418                 return -ENOMEM;
419         class_pktcdvd->name = DRIVER_NAME;
420         class_pktcdvd->owner = THIS_MODULE;
421         class_pktcdvd->class_release = class_pktcdvd_release;
422         class_pktcdvd->class_attrs = class_pktcdvd_attrs;
423         ret = class_register(class_pktcdvd);
424         if (ret) {
425                 kfree(class_pktcdvd);
426                 class_pktcdvd = NULL;
427                 printk(DRIVER_NAME": failed to create class pktcdvd\n");
428                 return ret;
429         }
430         return 0;
431 }
432
433 static void pkt_sysfs_cleanup(void)
434 {
435         if (class_pktcdvd)
436                 class_destroy(class_pktcdvd);
437         class_pktcdvd = NULL;
438 }
439
440 /********************************************************************
441   entries in debugfs
442
443   /sys/kernel/debug/pktcdvd[0-7]/
444                         info
445
446  *******************************************************************/
447
448 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
449 {
450         return pkt_seq_show(m, p);
451 }
452
453 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
454 {
455         return single_open(file, pkt_debugfs_seq_show, inode->i_private);
456 }
457
458 static const struct file_operations debug_fops = {
459         .open           = pkt_debugfs_fops_open,
460         .read           = seq_read,
461         .llseek         = seq_lseek,
462         .release        = single_release,
463         .owner          = THIS_MODULE,
464 };
465
466 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
467 {
468         if (!pkt_debugfs_root)
469                 return;
470         pd->dfs_f_info = NULL;
471         pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
472         if (IS_ERR(pd->dfs_d_root)) {
473                 pd->dfs_d_root = NULL;
474                 return;
475         }
476         pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
477                                 pd->dfs_d_root, pd, &debug_fops);
478         if (IS_ERR(pd->dfs_f_info)) {
479                 pd->dfs_f_info = NULL;
480                 return;
481         }
482 }
483
484 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
485 {
486         if (!pkt_debugfs_root)
487                 return;
488         if (pd->dfs_f_info)
489                 debugfs_remove(pd->dfs_f_info);
490         pd->dfs_f_info = NULL;
491         if (pd->dfs_d_root)
492                 debugfs_remove(pd->dfs_d_root);
493         pd->dfs_d_root = NULL;
494 }
495
496 static void pkt_debugfs_init(void)
497 {
498         pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
499         if (IS_ERR(pkt_debugfs_root)) {
500                 pkt_debugfs_root = NULL;
501                 return;
502         }
503 }
504
505 static void pkt_debugfs_cleanup(void)
506 {
507         if (!pkt_debugfs_root)
508                 return;
509         debugfs_remove(pkt_debugfs_root);
510         pkt_debugfs_root = NULL;
511 }
512
513 /* ----------------------------------------------------------*/
514
515
516 static void pkt_bio_finished(struct pktcdvd_device *pd)
517 {
518         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
519         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
520                 VPRINTK(DRIVER_NAME": queue empty\n");
521                 atomic_set(&pd->iosched.attention, 1);
522                 wake_up(&pd->wqueue);
523         }
524 }
525
526 /*
527  * Allocate a packet_data struct
528  */
529 static struct packet_data *pkt_alloc_packet_data(int frames)
530 {
531         int i;
532         struct packet_data *pkt;
533
534         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
535         if (!pkt)
536                 goto no_pkt;
537
538         pkt->frames = frames;
539         pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
540         if (!pkt->w_bio)
541                 goto no_bio;
542
543         for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
544                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
545                 if (!pkt->pages[i])
546                         goto no_page;
547         }
548
549         spin_lock_init(&pkt->lock);
550         bio_list_init(&pkt->orig_bios);
551
552         for (i = 0; i < frames; i++) {
553                 struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
554                 if (!bio)
555                         goto no_rd_bio;
556
557                 pkt->r_bios[i] = bio;
558         }
559
560         return pkt;
561
562 no_rd_bio:
563         for (i = 0; i < frames; i++) {
564                 struct bio *bio = pkt->r_bios[i];
565                 if (bio)
566                         bio_put(bio);
567         }
568
569 no_page:
570         for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
571                 if (pkt->pages[i])
572                         __free_page(pkt->pages[i]);
573         bio_put(pkt->w_bio);
574 no_bio:
575         kfree(pkt);
576 no_pkt:
577         return NULL;
578 }
579
580 /*
581  * Free a packet_data struct
582  */
583 static void pkt_free_packet_data(struct packet_data *pkt)
584 {
585         int i;
586
587         for (i = 0; i < pkt->frames; i++) {
588                 struct bio *bio = pkt->r_bios[i];
589                 if (bio)
590                         bio_put(bio);
591         }
592         for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
593                 __free_page(pkt->pages[i]);
594         bio_put(pkt->w_bio);
595         kfree(pkt);
596 }
597
598 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
599 {
600         struct packet_data *pkt, *next;
601
602         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
603
604         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
605                 pkt_free_packet_data(pkt);
606         }
607         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
608 }
609
610 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
611 {
612         struct packet_data *pkt;
613
614         BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
615
616         while (nr_packets > 0) {
617                 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
618                 if (!pkt) {
619                         pkt_shrink_pktlist(pd);
620                         return 0;
621                 }
622                 pkt->id = nr_packets;
623                 pkt->pd = pd;
624                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
625                 nr_packets--;
626         }
627         return 1;
628 }
629
630 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
631 {
632         struct rb_node *n = rb_next(&node->rb_node);
633         if (!n)
634                 return NULL;
635         return rb_entry(n, struct pkt_rb_node, rb_node);
636 }
637
638 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
639 {
640         rb_erase(&node->rb_node, &pd->bio_queue);
641         mempool_free(node, pd->rb_pool);
642         pd->bio_queue_size--;
643         BUG_ON(pd->bio_queue_size < 0);
644 }
645
646 /*
647  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
648  */
649 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
650 {
651         struct rb_node *n = pd->bio_queue.rb_node;
652         struct rb_node *next;
653         struct pkt_rb_node *tmp;
654
655         if (!n) {
656                 BUG_ON(pd->bio_queue_size > 0);
657                 return NULL;
658         }
659
660         for (;;) {
661                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
662                 if (s <= tmp->bio->bi_sector)
663                         next = n->rb_left;
664                 else
665                         next = n->rb_right;
666                 if (!next)
667                         break;
668                 n = next;
669         }
670
671         if (s > tmp->bio->bi_sector) {
672                 tmp = pkt_rbtree_next(tmp);
673                 if (!tmp)
674                         return NULL;
675         }
676         BUG_ON(s > tmp->bio->bi_sector);
677         return tmp;
678 }
679
680 /*
681  * Insert a node into the pd->bio_queue rb tree.
682  */
683 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
684 {
685         struct rb_node **p = &pd->bio_queue.rb_node;
686         struct rb_node *parent = NULL;
687         sector_t s = node->bio->bi_sector;
688         struct pkt_rb_node *tmp;
689
690         while (*p) {
691                 parent = *p;
692                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
693                 if (s < tmp->bio->bi_sector)
694                         p = &(*p)->rb_left;
695                 else
696                         p = &(*p)->rb_right;
697         }
698         rb_link_node(&node->rb_node, parent, p);
699         rb_insert_color(&node->rb_node, &pd->bio_queue);
700         pd->bio_queue_size++;
701 }
702
703 /*
704  * Send a packet_command to the underlying block device and
705  * wait for completion.
706  */
707 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
708 {
709         struct request_queue *q = bdev_get_queue(pd->bdev);
710         struct request *rq;
711         int ret = 0;
712
713         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
714                              WRITE : READ, __GFP_WAIT);
715
716         if (cgc->buflen) {
717                 if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
718                         goto out;
719         }
720
721         rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
722         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
723
724         rq->timeout = 60*HZ;
725         rq->cmd_type = REQ_TYPE_BLOCK_PC;
726         if (cgc->quiet)
727                 rq->cmd_flags |= REQ_QUIET;
728
729         blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
730         if (rq->errors)
731                 ret = -EIO;
732 out:
733         blk_put_request(rq);
734         return ret;
735 }
736
737 /*
738  * A generic sense dump / resolve mechanism should be implemented across
739  * all ATAPI + SCSI devices.
740  */
741 static void pkt_dump_sense(struct packet_command *cgc)
742 {
743         static char *info[9] = { "No sense", "Recovered error", "Not ready",
744                                  "Medium error", "Hardware error", "Illegal request",
745                                  "Unit attention", "Data protect", "Blank check" };
746         int i;
747         struct request_sense *sense = cgc->sense;
748
749         printk(DRIVER_NAME":");
750         for (i = 0; i < CDROM_PACKET_SIZE; i++)
751                 printk(" %02x", cgc->cmd[i]);
752         printk(" - ");
753
754         if (sense == NULL) {
755                 printk("no sense\n");
756                 return;
757         }
758
759         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
760
761         if (sense->sense_key > 8) {
762                 printk(" (INVALID)\n");
763                 return;
764         }
765
766         printk(" (%s)\n", info[sense->sense_key]);
767 }
768
769 /*
770  * flush the drive cache to media
771  */
772 static int pkt_flush_cache(struct pktcdvd_device *pd)
773 {
774         struct packet_command cgc;
775
776         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
777         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
778         cgc.quiet = 1;
779
780         /*
781          * the IMMED bit -- we default to not setting it, although that
782          * would allow a much faster close, this is safer
783          */
784 #if 0
785         cgc.cmd[1] = 1 << 1;
786 #endif
787         return pkt_generic_packet(pd, &cgc);
788 }
789
790 /*
791  * speed is given as the normal factor, e.g. 4 for 4x
792  */
793 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
794                                 unsigned write_speed, unsigned read_speed)
795 {
796         struct packet_command cgc;
797         struct request_sense sense;
798         int ret;
799
800         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
801         cgc.sense = &sense;
802         cgc.cmd[0] = GPCMD_SET_SPEED;
803         cgc.cmd[2] = (read_speed >> 8) & 0xff;
804         cgc.cmd[3] = read_speed & 0xff;
805         cgc.cmd[4] = (write_speed >> 8) & 0xff;
806         cgc.cmd[5] = write_speed & 0xff;
807
808         if ((ret = pkt_generic_packet(pd, &cgc)))
809                 pkt_dump_sense(&cgc);
810
811         return ret;
812 }
813
814 /*
815  * Queue a bio for processing by the low-level CD device. Must be called
816  * from process context.
817  */
818 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
819 {
820         spin_lock(&pd->iosched.lock);
821         if (bio_data_dir(bio) == READ)
822                 bio_list_add(&pd->iosched.read_queue, bio);
823         else
824                 bio_list_add(&pd->iosched.write_queue, bio);
825         spin_unlock(&pd->iosched.lock);
826
827         atomic_set(&pd->iosched.attention, 1);
828         wake_up(&pd->wqueue);
829 }
830
831 /*
832  * Process the queued read/write requests. This function handles special
833  * requirements for CDRW drives:
834  * - A cache flush command must be inserted before a read request if the
835  *   previous request was a write.
836  * - Switching between reading and writing is slow, so don't do it more often
837  *   than necessary.
838  * - Optimize for throughput at the expense of latency. This means that streaming
839  *   writes will never be interrupted by a read, but if the drive has to seek
840  *   before the next write, switch to reading instead if there are any pending
841  *   read requests.
842  * - Set the read speed according to current usage pattern. When only reading
843  *   from the device, it's best to use the highest possible read speed, but
844  *   when switching often between reading and writing, it's better to have the
845  *   same read and write speeds.
846  */
847 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
848 {
849
850         if (atomic_read(&pd->iosched.attention) == 0)
851                 return;
852         atomic_set(&pd->iosched.attention, 0);
853
854         for (;;) {
855                 struct bio *bio;
856                 int reads_queued, writes_queued;
857
858                 spin_lock(&pd->iosched.lock);
859                 reads_queued = !bio_list_empty(&pd->iosched.read_queue);
860                 writes_queued = !bio_list_empty(&pd->iosched.write_queue);
861                 spin_unlock(&pd->iosched.lock);
862
863                 if (!reads_queued && !writes_queued)
864                         break;
865
866                 if (pd->iosched.writing) {
867                         int need_write_seek = 1;
868                         spin_lock(&pd->iosched.lock);
869                         bio = bio_list_peek(&pd->iosched.write_queue);
870                         spin_unlock(&pd->iosched.lock);
871                         if (bio && (bio->bi_sector == pd->iosched.last_write))
872                                 need_write_seek = 0;
873                         if (need_write_seek && reads_queued) {
874                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
875                                         VPRINTK(DRIVER_NAME": write, waiting\n");
876                                         break;
877                                 }
878                                 pkt_flush_cache(pd);
879                                 pd->iosched.writing = 0;
880                         }
881                 } else {
882                         if (!reads_queued && writes_queued) {
883                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
884                                         VPRINTK(DRIVER_NAME": read, waiting\n");
885                                         break;
886                                 }
887                                 pd->iosched.writing = 1;
888                         }
889                 }
890
891                 spin_lock(&pd->iosched.lock);
892                 if (pd->iosched.writing)
893                         bio = bio_list_pop(&pd->iosched.write_queue);
894                 else
895                         bio = bio_list_pop(&pd->iosched.read_queue);
896                 spin_unlock(&pd->iosched.lock);
897
898                 if (!bio)
899                         continue;
900
901                 if (bio_data_dir(bio) == READ)
902                         pd->iosched.successive_reads += bio->bi_size >> 10;
903                 else {
904                         pd->iosched.successive_reads = 0;
905                         pd->iosched.last_write = bio_end_sector(bio);
906                 }
907                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
908                         if (pd->read_speed == pd->write_speed) {
909                                 pd->read_speed = MAX_SPEED;
910                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
911                         }
912                 } else {
913                         if (pd->read_speed != pd->write_speed) {
914                                 pd->read_speed = pd->write_speed;
915                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
916                         }
917                 }
918
919                 atomic_inc(&pd->cdrw.pending_bios);
920                 generic_make_request(bio);
921         }
922 }
923
924 /*
925  * Special care is needed if the underlying block device has a small
926  * max_phys_segments value.
927  */
928 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
929 {
930         if ((pd->settings.size << 9) / CD_FRAMESIZE
931             <= queue_max_segments(q)) {
932                 /*
933                  * The cdrom device can handle one segment/frame
934                  */
935                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
936                 return 0;
937         } else if ((pd->settings.size << 9) / PAGE_SIZE
938                    <= queue_max_segments(q)) {
939                 /*
940                  * We can handle this case at the expense of some extra memory
941                  * copies during write operations
942                  */
943                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
944                 return 0;
945         } else {
946                 printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
947                 return -EIO;
948         }
949 }
950
951 /*
952  * Copy all data for this packet to pkt->pages[], so that
953  * a) The number of required segments for the write bio is minimized, which
954  *    is necessary for some scsi controllers.
955  * b) The data can be used as cache to avoid read requests if we receive a
956  *    new write request for the same zone.
957  */
958 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
959 {
960         int f, p, offs;
961
962         /* Copy all data to pkt->pages[] */
963         p = 0;
964         offs = 0;
965         for (f = 0; f < pkt->frames; f++) {
966                 if (bvec[f].bv_page != pkt->pages[p]) {
967                         void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset;
968                         void *vto = page_address(pkt->pages[p]) + offs;
969                         memcpy(vto, vfrom, CD_FRAMESIZE);
970                         kunmap_atomic(vfrom);
971                         bvec[f].bv_page = pkt->pages[p];
972                         bvec[f].bv_offset = offs;
973                 } else {
974                         BUG_ON(bvec[f].bv_offset != offs);
975                 }
976                 offs += CD_FRAMESIZE;
977                 if (offs >= PAGE_SIZE) {
978                         offs = 0;
979                         p++;
980                 }
981         }
982 }
983
984 static void pkt_end_io_read(struct bio *bio, int err)
985 {
986         struct packet_data *pkt = bio->bi_private;
987         struct pktcdvd_device *pd = pkt->pd;
988         BUG_ON(!pd);
989
990         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
991                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
992
993         if (err)
994                 atomic_inc(&pkt->io_errors);
995         if (atomic_dec_and_test(&pkt->io_wait)) {
996                 atomic_inc(&pkt->run_sm);
997                 wake_up(&pd->wqueue);
998         }
999         pkt_bio_finished(pd);
1000 }
1001
1002 static void pkt_end_io_packet_write(struct bio *bio, int err)
1003 {
1004         struct packet_data *pkt = bio->bi_private;
1005         struct pktcdvd_device *pd = pkt->pd;
1006         BUG_ON(!pd);
1007
1008         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1009
1010         pd->stats.pkt_ended++;
1011
1012         pkt_bio_finished(pd);
1013         atomic_dec(&pkt->io_wait);
1014         atomic_inc(&pkt->run_sm);
1015         wake_up(&pd->wqueue);
1016 }
1017
1018 /*
1019  * Schedule reads for the holes in a packet
1020  */
1021 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1022 {
1023         int frames_read = 0;
1024         struct bio *bio;
1025         int f;
1026         char written[PACKET_MAX_SIZE];
1027
1028         BUG_ON(bio_list_empty(&pkt->orig_bios));
1029
1030         atomic_set(&pkt->io_wait, 0);
1031         atomic_set(&pkt->io_errors, 0);
1032
1033         /*
1034          * Figure out which frames we need to read before we can write.
1035          */
1036         memset(written, 0, sizeof(written));
1037         spin_lock(&pkt->lock);
1038         bio_list_for_each(bio, &pkt->orig_bios) {
1039                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1040                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1041                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1042                 BUG_ON(first_frame < 0);
1043                 BUG_ON(first_frame + num_frames > pkt->frames);
1044                 for (f = first_frame; f < first_frame + num_frames; f++)
1045                         written[f] = 1;
1046         }
1047         spin_unlock(&pkt->lock);
1048
1049         if (pkt->cache_valid) {
1050                 VPRINTK("pkt_gather_data: zone %llx cached\n",
1051                         (unsigned long long)pkt->sector);
1052                 goto out_account;
1053         }
1054
1055         /*
1056          * Schedule reads for missing parts of the packet.
1057          */
1058         for (f = 0; f < pkt->frames; f++) {
1059                 int p, offset;
1060
1061                 if (written[f])
1062                         continue;
1063
1064                 bio = pkt->r_bios[f];
1065                 bio_reset(bio);
1066                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1067                 bio->bi_bdev = pd->bdev;
1068                 bio->bi_end_io = pkt_end_io_read;
1069                 bio->bi_private = pkt;
1070
1071                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1072                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1073                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1074                         f, pkt->pages[p], offset);
1075                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1076                         BUG();
1077
1078                 atomic_inc(&pkt->io_wait);
1079                 bio->bi_rw = READ;
1080                 pkt_queue_bio(pd, bio);
1081                 frames_read++;
1082         }
1083
1084 out_account:
1085         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1086                 frames_read, (unsigned long long)pkt->sector);
1087         pd->stats.pkt_started++;
1088         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1089 }
1090
1091 /*
1092  * Find a packet matching zone, or the least recently used packet if
1093  * there is no match.
1094  */
1095 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1096 {
1097         struct packet_data *pkt;
1098
1099         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1100                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1101                         list_del_init(&pkt->list);
1102                         if (pkt->sector != zone)
1103                                 pkt->cache_valid = 0;
1104                         return pkt;
1105                 }
1106         }
1107         BUG();
1108         return NULL;
1109 }
1110
1111 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1112 {
1113         if (pkt->cache_valid) {
1114                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1115         } else {
1116                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1117         }
1118 }
1119
1120 /*
1121  * recover a failed write, query for relocation if possible
1122  *
1123  * returns 1 if recovery is possible, or 0 if not
1124  *
1125  */
1126 static int pkt_start_recovery(struct packet_data *pkt)
1127 {
1128         /*
1129          * FIXME. We need help from the file system to implement
1130          * recovery handling.
1131          */
1132         return 0;
1133 #if 0
1134         struct request *rq = pkt->rq;
1135         struct pktcdvd_device *pd = rq->rq_disk->private_data;
1136         struct block_device *pkt_bdev;
1137         struct super_block *sb = NULL;
1138         unsigned long old_block, new_block;
1139         sector_t new_sector;
1140
1141         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1142         if (pkt_bdev) {
1143                 sb = get_super(pkt_bdev);
1144                 bdput(pkt_bdev);
1145         }
1146
1147         if (!sb)
1148                 return 0;
1149
1150         if (!sb->s_op->relocate_blocks)
1151                 goto out;
1152
1153         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1154         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1155                 goto out;
1156
1157         new_sector = new_block * (CD_FRAMESIZE >> 9);
1158         pkt->sector = new_sector;
1159
1160         bio_reset(pkt->bio);
1161         pkt->bio->bi_bdev = pd->bdev;
1162         pkt->bio->bi_rw = REQ_WRITE;
1163         pkt->bio->bi_sector = new_sector;
1164         pkt->bio->bi_size = pkt->frames * CD_FRAMESIZE;
1165         pkt->bio->bi_vcnt = pkt->frames;
1166
1167         pkt->bio->bi_end_io = pkt_end_io_packet_write;
1168         pkt->bio->bi_private = pkt;
1169
1170         drop_super(sb);
1171         return 1;
1172
1173 out:
1174         drop_super(sb);
1175         return 0;
1176 #endif
1177 }
1178
1179 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1180 {
1181 #if PACKET_DEBUG > 1
1182         static const char *state_name[] = {
1183                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1184         };
1185         enum packet_data_state old_state = pkt->state;
1186         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1187                 state_name[old_state], state_name[state]);
1188 #endif
1189         pkt->state = state;
1190 }
1191
1192 /*
1193  * Scan the work queue to see if we can start a new packet.
1194  * returns non-zero if any work was done.
1195  */
1196 static int pkt_handle_queue(struct pktcdvd_device *pd)
1197 {
1198         struct packet_data *pkt, *p;
1199         struct bio *bio = NULL;
1200         sector_t zone = 0; /* Suppress gcc warning */
1201         struct pkt_rb_node *node, *first_node;
1202         struct rb_node *n;
1203         int wakeup;
1204
1205         VPRINTK("handle_queue\n");
1206
1207         atomic_set(&pd->scan_queue, 0);
1208
1209         if (list_empty(&pd->cdrw.pkt_free_list)) {
1210                 VPRINTK("handle_queue: no pkt\n");
1211                 return 0;
1212         }
1213
1214         /*
1215          * Try to find a zone we are not already working on.
1216          */
1217         spin_lock(&pd->lock);
1218         first_node = pkt_rbtree_find(pd, pd->current_sector);
1219         if (!first_node) {
1220                 n = rb_first(&pd->bio_queue);
1221                 if (n)
1222                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1223         }
1224         node = first_node;
1225         while (node) {
1226                 bio = node->bio;
1227                 zone = ZONE(bio->bi_sector, pd);
1228                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1229                         if (p->sector == zone) {
1230                                 bio = NULL;
1231                                 goto try_next_bio;
1232                         }
1233                 }
1234                 break;
1235 try_next_bio:
1236                 node = pkt_rbtree_next(node);
1237                 if (!node) {
1238                         n = rb_first(&pd->bio_queue);
1239                         if (n)
1240                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
1241                 }
1242                 if (node == first_node)
1243                         node = NULL;
1244         }
1245         spin_unlock(&pd->lock);
1246         if (!bio) {
1247                 VPRINTK("handle_queue: no bio\n");
1248                 return 0;
1249         }
1250
1251         pkt = pkt_get_packet_data(pd, zone);
1252
1253         pd->current_sector = zone + pd->settings.size;
1254         pkt->sector = zone;
1255         BUG_ON(pkt->frames != pd->settings.size >> 2);
1256         pkt->write_size = 0;
1257
1258         /*
1259          * Scan work queue for bios in the same zone and link them
1260          * to this packet.
1261          */
1262         spin_lock(&pd->lock);
1263         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1264         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1265                 bio = node->bio;
1266                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
1267                         (unsigned long long)ZONE(bio->bi_sector, pd));
1268                 if (ZONE(bio->bi_sector, pd) != zone)
1269                         break;
1270                 pkt_rbtree_erase(pd, node);
1271                 spin_lock(&pkt->lock);
1272                 bio_list_add(&pkt->orig_bios, bio);
1273                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1274                 spin_unlock(&pkt->lock);
1275         }
1276         /* check write congestion marks, and if bio_queue_size is
1277            below, wake up any waiters */
1278         wakeup = (pd->write_congestion_on > 0
1279                         && pd->bio_queue_size <= pd->write_congestion_off);
1280         spin_unlock(&pd->lock);
1281         if (wakeup) {
1282                 clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1283                                         BLK_RW_ASYNC);
1284         }
1285
1286         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1287         pkt_set_state(pkt, PACKET_WAITING_STATE);
1288         atomic_set(&pkt->run_sm, 1);
1289
1290         spin_lock(&pd->cdrw.active_list_lock);
1291         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1292         spin_unlock(&pd->cdrw.active_list_lock);
1293
1294         return 1;
1295 }
1296
1297 /*
1298  * Assemble a bio to write one packet and queue the bio for processing
1299  * by the underlying block device.
1300  */
1301 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1302 {
1303         int f;
1304         struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1305
1306         bio_reset(pkt->w_bio);
1307         pkt->w_bio->bi_sector = pkt->sector;
1308         pkt->w_bio->bi_bdev = pd->bdev;
1309         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1310         pkt->w_bio->bi_private = pkt;
1311
1312         /* XXX: locking? */
1313         for (f = 0; f < pkt->frames; f++) {
1314                 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1315                 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1316                 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1317                         BUG();
1318         }
1319         VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1320
1321         /*
1322          * Fill-in bvec with data from orig_bios.
1323          */
1324         spin_lock(&pkt->lock);
1325         bio_copy_data(pkt->w_bio, pkt->orig_bios.head);
1326
1327         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1328         spin_unlock(&pkt->lock);
1329
1330         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1331                 pkt->write_size, (unsigned long long)pkt->sector);
1332
1333         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1334                 pkt_make_local_copy(pkt, bvec);
1335                 pkt->cache_valid = 1;
1336         } else {
1337                 pkt->cache_valid = 0;
1338         }
1339
1340         /* Start the write request */
1341         atomic_set(&pkt->io_wait, 1);
1342         pkt->w_bio->bi_rw = WRITE;
1343         pkt_queue_bio(pd, pkt->w_bio);
1344 }
1345
1346 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1347 {
1348         struct bio *bio;
1349
1350         if (!uptodate)
1351                 pkt->cache_valid = 0;
1352
1353         /* Finish all bios corresponding to this packet */
1354         while ((bio = bio_list_pop(&pkt->orig_bios)))
1355                 bio_endio(bio, uptodate ? 0 : -EIO);
1356 }
1357
1358 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1359 {
1360         int uptodate;
1361
1362         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1363
1364         for (;;) {
1365                 switch (pkt->state) {
1366                 case PACKET_WAITING_STATE:
1367                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1368                                 return;
1369
1370                         pkt->sleep_time = 0;
1371                         pkt_gather_data(pd, pkt);
1372                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1373                         break;
1374
1375                 case PACKET_READ_WAIT_STATE:
1376                         if (atomic_read(&pkt->io_wait) > 0)
1377                                 return;
1378
1379                         if (atomic_read(&pkt->io_errors) > 0) {
1380                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1381                         } else {
1382                                 pkt_start_write(pd, pkt);
1383                         }
1384                         break;
1385
1386                 case PACKET_WRITE_WAIT_STATE:
1387                         if (atomic_read(&pkt->io_wait) > 0)
1388                                 return;
1389
1390                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1391                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1392                         } else {
1393                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1394                         }
1395                         break;
1396
1397                 case PACKET_RECOVERY_STATE:
1398                         if (pkt_start_recovery(pkt)) {
1399                                 pkt_start_write(pd, pkt);
1400                         } else {
1401                                 VPRINTK("No recovery possible\n");
1402                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1403                         }
1404                         break;
1405
1406                 case PACKET_FINISHED_STATE:
1407                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1408                         pkt_finish_packet(pkt, uptodate);
1409                         return;
1410
1411                 default:
1412                         BUG();
1413                         break;
1414                 }
1415         }
1416 }
1417
1418 static void pkt_handle_packets(struct pktcdvd_device *pd)
1419 {
1420         struct packet_data *pkt, *next;
1421
1422         VPRINTK("pkt_handle_packets\n");
1423
1424         /*
1425          * Run state machine for active packets
1426          */
1427         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1428                 if (atomic_read(&pkt->run_sm) > 0) {
1429                         atomic_set(&pkt->run_sm, 0);
1430                         pkt_run_state_machine(pd, pkt);
1431                 }
1432         }
1433
1434         /*
1435          * Move no longer active packets to the free list
1436          */
1437         spin_lock(&pd->cdrw.active_list_lock);
1438         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1439                 if (pkt->state == PACKET_FINISHED_STATE) {
1440                         list_del(&pkt->list);
1441                         pkt_put_packet_data(pd, pkt);
1442                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1443                         atomic_set(&pd->scan_queue, 1);
1444                 }
1445         }
1446         spin_unlock(&pd->cdrw.active_list_lock);
1447 }
1448
1449 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1450 {
1451         struct packet_data *pkt;
1452         int i;
1453
1454         for (i = 0; i < PACKET_NUM_STATES; i++)
1455                 states[i] = 0;
1456
1457         spin_lock(&pd->cdrw.active_list_lock);
1458         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1459                 states[pkt->state]++;
1460         }
1461         spin_unlock(&pd->cdrw.active_list_lock);
1462 }
1463
1464 /*
1465  * kcdrwd is woken up when writes have been queued for one of our
1466  * registered devices
1467  */
1468 static int kcdrwd(void *foobar)
1469 {
1470         struct pktcdvd_device *pd = foobar;
1471         struct packet_data *pkt;
1472         long min_sleep_time, residue;
1473
1474         set_user_nice(current, -20);
1475         set_freezable();
1476
1477         for (;;) {
1478                 DECLARE_WAITQUEUE(wait, current);
1479
1480                 /*
1481                  * Wait until there is something to do
1482                  */
1483                 add_wait_queue(&pd->wqueue, &wait);
1484                 for (;;) {
1485                         set_current_state(TASK_INTERRUPTIBLE);
1486
1487                         /* Check if we need to run pkt_handle_queue */
1488                         if (atomic_read(&pd->scan_queue) > 0)
1489                                 goto work_to_do;
1490
1491                         /* Check if we need to run the state machine for some packet */
1492                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1493                                 if (atomic_read(&pkt->run_sm) > 0)
1494                                         goto work_to_do;
1495                         }
1496
1497                         /* Check if we need to process the iosched queues */
1498                         if (atomic_read(&pd->iosched.attention) != 0)
1499                                 goto work_to_do;
1500
1501                         /* Otherwise, go to sleep */
1502                         if (PACKET_DEBUG > 1) {
1503                                 int states[PACKET_NUM_STATES];
1504                                 pkt_count_states(pd, states);
1505                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1506                                         states[0], states[1], states[2], states[3],
1507                                         states[4], states[5]);
1508                         }
1509
1510                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1511                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1512                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1513                                         min_sleep_time = pkt->sleep_time;
1514                         }
1515
1516                         VPRINTK("kcdrwd: sleeping\n");
1517                         residue = schedule_timeout(min_sleep_time);
1518                         VPRINTK("kcdrwd: wake up\n");
1519
1520                         /* make swsusp happy with our thread */
1521                         try_to_freeze();
1522
1523                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1524                                 if (!pkt->sleep_time)
1525                                         continue;
1526                                 pkt->sleep_time -= min_sleep_time - residue;
1527                                 if (pkt->sleep_time <= 0) {
1528                                         pkt->sleep_time = 0;
1529                                         atomic_inc(&pkt->run_sm);
1530                                 }
1531                         }
1532
1533                         if (kthread_should_stop())
1534                                 break;
1535                 }
1536 work_to_do:
1537                 set_current_state(TASK_RUNNING);
1538                 remove_wait_queue(&pd->wqueue, &wait);
1539
1540                 if (kthread_should_stop())
1541                         break;
1542
1543                 /*
1544                  * if pkt_handle_queue returns true, we can queue
1545                  * another request.
1546                  */
1547                 while (pkt_handle_queue(pd))
1548                         ;
1549
1550                 /*
1551                  * Handle packet state machine
1552                  */
1553                 pkt_handle_packets(pd);
1554
1555                 /*
1556                  * Handle iosched queues
1557                  */
1558                 pkt_iosched_process_queue(pd);
1559         }
1560
1561         return 0;
1562 }
1563
1564 static void pkt_print_settings(struct pktcdvd_device *pd)
1565 {
1566         printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1567         printk("%u blocks, ", pd->settings.size >> 2);
1568         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1569 }
1570
1571 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1572 {
1573         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1574
1575         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1576         cgc->cmd[2] = page_code | (page_control << 6);
1577         cgc->cmd[7] = cgc->buflen >> 8;
1578         cgc->cmd[8] = cgc->buflen & 0xff;
1579         cgc->data_direction = CGC_DATA_READ;
1580         return pkt_generic_packet(pd, cgc);
1581 }
1582
1583 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1584 {
1585         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1586         memset(cgc->buffer, 0, 2);
1587         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1588         cgc->cmd[1] = 0x10;             /* PF */
1589         cgc->cmd[7] = cgc->buflen >> 8;
1590         cgc->cmd[8] = cgc->buflen & 0xff;
1591         cgc->data_direction = CGC_DATA_WRITE;
1592         return pkt_generic_packet(pd, cgc);
1593 }
1594
1595 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1596 {
1597         struct packet_command cgc;
1598         int ret;
1599
1600         /* set up command and get the disc info */
1601         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1602         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1603         cgc.cmd[8] = cgc.buflen = 2;
1604         cgc.quiet = 1;
1605
1606         if ((ret = pkt_generic_packet(pd, &cgc)))
1607                 return ret;
1608
1609         /* not all drives have the same disc_info length, so requeue
1610          * packet with the length the drive tells us it can supply
1611          */
1612         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1613                      sizeof(di->disc_information_length);
1614
1615         if (cgc.buflen > sizeof(disc_information))
1616                 cgc.buflen = sizeof(disc_information);
1617
1618         cgc.cmd[8] = cgc.buflen;
1619         return pkt_generic_packet(pd, &cgc);
1620 }
1621
1622 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1623 {
1624         struct packet_command cgc;
1625         int ret;
1626
1627         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1628         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1629         cgc.cmd[1] = type & 3;
1630         cgc.cmd[4] = (track & 0xff00) >> 8;
1631         cgc.cmd[5] = track & 0xff;
1632         cgc.cmd[8] = 8;
1633         cgc.quiet = 1;
1634
1635         if ((ret = pkt_generic_packet(pd, &cgc)))
1636                 return ret;
1637
1638         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1639                      sizeof(ti->track_information_length);
1640
1641         if (cgc.buflen > sizeof(track_information))
1642                 cgc.buflen = sizeof(track_information);
1643
1644         cgc.cmd[8] = cgc.buflen;
1645         return pkt_generic_packet(pd, &cgc);
1646 }
1647
1648 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1649                                                 long *last_written)
1650 {
1651         disc_information di;
1652         track_information ti;
1653         __u32 last_track;
1654         int ret = -1;
1655
1656         if ((ret = pkt_get_disc_info(pd, &di)))
1657                 return ret;
1658
1659         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1660         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1661                 return ret;
1662
1663         /* if this track is blank, try the previous. */
1664         if (ti.blank) {
1665                 last_track--;
1666                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1667                         return ret;
1668         }
1669
1670         /* if last recorded field is valid, return it. */
1671         if (ti.lra_v) {
1672                 *last_written = be32_to_cpu(ti.last_rec_address);
1673         } else {
1674                 /* make it up instead */
1675                 *last_written = be32_to_cpu(ti.track_start) +
1676                                 be32_to_cpu(ti.track_size);
1677                 if (ti.free_blocks)
1678                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1679         }
1680         return 0;
1681 }
1682
1683 /*
1684  * write mode select package based on pd->settings
1685  */
1686 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1687 {
1688         struct packet_command cgc;
1689         struct request_sense sense;
1690         write_param_page *wp;
1691         char buffer[128];
1692         int ret, size;
1693
1694         /* doesn't apply to DVD+RW or DVD-RAM */
1695         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1696                 return 0;
1697
1698         memset(buffer, 0, sizeof(buffer));
1699         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1700         cgc.sense = &sense;
1701         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1702                 pkt_dump_sense(&cgc);
1703                 return ret;
1704         }
1705
1706         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1707         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1708         if (size > sizeof(buffer))
1709                 size = sizeof(buffer);
1710
1711         /*
1712          * now get it all
1713          */
1714         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1715         cgc.sense = &sense;
1716         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1717                 pkt_dump_sense(&cgc);
1718                 return ret;
1719         }
1720
1721         /*
1722          * write page is offset header + block descriptor length
1723          */
1724         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1725
1726         wp->fp = pd->settings.fp;
1727         wp->track_mode = pd->settings.track_mode;
1728         wp->write_type = pd->settings.write_type;
1729         wp->data_block_type = pd->settings.block_mode;
1730
1731         wp->multi_session = 0;
1732
1733 #ifdef PACKET_USE_LS
1734         wp->link_size = 7;
1735         wp->ls_v = 1;
1736 #endif
1737
1738         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1739                 wp->session_format = 0;
1740                 wp->subhdr2 = 0x20;
1741         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1742                 wp->session_format = 0x20;
1743                 wp->subhdr2 = 8;
1744 #if 0
1745                 wp->mcn[0] = 0x80;
1746                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1747 #endif
1748         } else {
1749                 /*
1750                  * paranoia
1751                  */
1752                 printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1753                 return 1;
1754         }
1755         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1756
1757         cgc.buflen = cgc.cmd[8] = size;
1758         if ((ret = pkt_mode_select(pd, &cgc))) {
1759                 pkt_dump_sense(&cgc);
1760                 return ret;
1761         }
1762
1763         pkt_print_settings(pd);
1764         return 0;
1765 }
1766
1767 /*
1768  * 1 -- we can write to this track, 0 -- we can't
1769  */
1770 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1771 {
1772         switch (pd->mmc3_profile) {
1773                 case 0x1a: /* DVD+RW */
1774                 case 0x12: /* DVD-RAM */
1775                         /* The track is always writable on DVD+RW/DVD-RAM */
1776                         return 1;
1777                 default:
1778                         break;
1779         }
1780
1781         if (!ti->packet || !ti->fp)
1782                 return 0;
1783
1784         /*
1785          * "good" settings as per Mt Fuji.
1786          */
1787         if (ti->rt == 0 && ti->blank == 0)
1788                 return 1;
1789
1790         if (ti->rt == 0 && ti->blank == 1)
1791                 return 1;
1792
1793         if (ti->rt == 1 && ti->blank == 0)
1794                 return 1;
1795
1796         printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1797         return 0;
1798 }
1799
1800 /*
1801  * 1 -- we can write to this disc, 0 -- we can't
1802  */
1803 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1804 {
1805         switch (pd->mmc3_profile) {
1806                 case 0x0a: /* CD-RW */
1807                 case 0xffff: /* MMC3 not supported */
1808                         break;
1809                 case 0x1a: /* DVD+RW */
1810                 case 0x13: /* DVD-RW */
1811                 case 0x12: /* DVD-RAM */
1812                         return 1;
1813                 default:
1814                         VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1815                         return 0;
1816         }
1817
1818         /*
1819          * for disc type 0xff we should probably reserve a new track.
1820          * but i'm not sure, should we leave this to user apps? probably.
1821          */
1822         if (di->disc_type == 0xff) {
1823                 printk(DRIVER_NAME": Unknown disc. No track?\n");
1824                 return 0;
1825         }
1826
1827         if (di->disc_type != 0x20 && di->disc_type != 0) {
1828                 printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1829                 return 0;
1830         }
1831
1832         if (di->erasable == 0) {
1833                 printk(DRIVER_NAME": Disc not erasable\n");
1834                 return 0;
1835         }
1836
1837         if (di->border_status == PACKET_SESSION_RESERVED) {
1838                 printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1839                 return 0;
1840         }
1841
1842         return 1;
1843 }
1844
1845 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1846 {
1847         struct packet_command cgc;
1848         unsigned char buf[12];
1849         disc_information di;
1850         track_information ti;
1851         int ret, track;
1852
1853         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1854         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1855         cgc.cmd[8] = 8;
1856         ret = pkt_generic_packet(pd, &cgc);
1857         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1858
1859         memset(&di, 0, sizeof(disc_information));
1860         memset(&ti, 0, sizeof(track_information));
1861
1862         if ((ret = pkt_get_disc_info(pd, &di))) {
1863                 printk("failed get_disc\n");
1864                 return ret;
1865         }
1866
1867         if (!pkt_writable_disc(pd, &di))
1868                 return -EROFS;
1869
1870         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1871
1872         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1873         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1874                 printk(DRIVER_NAME": failed get_track\n");
1875                 return ret;
1876         }
1877
1878         if (!pkt_writable_track(pd, &ti)) {
1879                 printk(DRIVER_NAME": can't write to this track\n");
1880                 return -EROFS;
1881         }
1882
1883         /*
1884          * we keep packet size in 512 byte units, makes it easier to
1885          * deal with request calculations.
1886          */
1887         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1888         if (pd->settings.size == 0) {
1889                 printk(DRIVER_NAME": detected zero packet size!\n");
1890                 return -ENXIO;
1891         }
1892         if (pd->settings.size > PACKET_MAX_SECTORS) {
1893                 printk(DRIVER_NAME": packet size is too big\n");
1894                 return -EROFS;
1895         }
1896         pd->settings.fp = ti.fp;
1897         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1898
1899         if (ti.nwa_v) {
1900                 pd->nwa = be32_to_cpu(ti.next_writable);
1901                 set_bit(PACKET_NWA_VALID, &pd->flags);
1902         }
1903
1904         /*
1905          * in theory we could use lra on -RW media as well and just zero
1906          * blocks that haven't been written yet, but in practice that
1907          * is just a no-go. we'll use that for -R, naturally.
1908          */
1909         if (ti.lra_v) {
1910                 pd->lra = be32_to_cpu(ti.last_rec_address);
1911                 set_bit(PACKET_LRA_VALID, &pd->flags);
1912         } else {
1913                 pd->lra = 0xffffffff;
1914                 set_bit(PACKET_LRA_VALID, &pd->flags);
1915         }
1916
1917         /*
1918          * fine for now
1919          */
1920         pd->settings.link_loss = 7;
1921         pd->settings.write_type = 0;    /* packet */
1922         pd->settings.track_mode = ti.track_mode;
1923
1924         /*
1925          * mode1 or mode2 disc
1926          */
1927         switch (ti.data_mode) {
1928                 case PACKET_MODE1:
1929                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1930                         break;
1931                 case PACKET_MODE2:
1932                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1933                         break;
1934                 default:
1935                         printk(DRIVER_NAME": unknown data mode\n");
1936                         return -EROFS;
1937         }
1938         return 0;
1939 }
1940
1941 /*
1942  * enable/disable write caching on drive
1943  */
1944 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
1945                                                 int set)
1946 {
1947         struct packet_command cgc;
1948         struct request_sense sense;
1949         unsigned char buf[64];
1950         int ret;
1951
1952         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1953         cgc.sense = &sense;
1954         cgc.buflen = pd->mode_offset + 12;
1955
1956         /*
1957          * caching mode page might not be there, so quiet this command
1958          */
1959         cgc.quiet = 1;
1960
1961         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1962                 return ret;
1963
1964         buf[pd->mode_offset + 10] |= (!!set << 2);
1965
1966         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1967         ret = pkt_mode_select(pd, &cgc);
1968         if (ret) {
1969                 printk(DRIVER_NAME": write caching control failed\n");
1970                 pkt_dump_sense(&cgc);
1971         } else if (!ret && set)
1972                 printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
1973         return ret;
1974 }
1975
1976 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1977 {
1978         struct packet_command cgc;
1979
1980         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1981         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1982         cgc.cmd[4] = lockflag ? 1 : 0;
1983         return pkt_generic_packet(pd, &cgc);
1984 }
1985
1986 /*
1987  * Returns drive maximum write speed
1988  */
1989 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1990                                                 unsigned *write_speed)
1991 {
1992         struct packet_command cgc;
1993         struct request_sense sense;
1994         unsigned char buf[256+18];
1995         unsigned char *cap_buf;
1996         int ret, offset;
1997
1998         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1999         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2000         cgc.sense = &sense;
2001
2002         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2003         if (ret) {
2004                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2005                              sizeof(struct mode_page_header);
2006                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2007                 if (ret) {
2008                         pkt_dump_sense(&cgc);
2009                         return ret;
2010                 }
2011         }
2012
2013         offset = 20;                        /* Obsoleted field, used by older drives */
2014         if (cap_buf[1] >= 28)
2015                 offset = 28;                /* Current write speed selected */
2016         if (cap_buf[1] >= 30) {
2017                 /* If the drive reports at least one "Logical Unit Write
2018                  * Speed Performance Descriptor Block", use the information
2019                  * in the first block. (contains the highest speed)
2020                  */
2021                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2022                 if (num_spdb > 0)
2023                         offset = 34;
2024         }
2025
2026         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2027         return 0;
2028 }
2029
2030 /* These tables from cdrecord - I don't have orange book */
2031 /* standard speed CD-RW (1-4x) */
2032 static char clv_to_speed[16] = {
2033         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2034            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2035 };
2036 /* high speed CD-RW (-10x) */
2037 static char hs_clv_to_speed[16] = {
2038         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2039            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2040 };
2041 /* ultra high speed CD-RW */
2042 static char us_clv_to_speed[16] = {
2043         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2044            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2045 };
2046
2047 /*
2048  * reads the maximum media speed from ATIP
2049  */
2050 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2051                                                 unsigned *speed)
2052 {
2053         struct packet_command cgc;
2054         struct request_sense sense;
2055         unsigned char buf[64];
2056         unsigned int size, st, sp;
2057         int ret;
2058
2059         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2060         cgc.sense = &sense;
2061         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2062         cgc.cmd[1] = 2;
2063         cgc.cmd[2] = 4; /* READ ATIP */
2064         cgc.cmd[8] = 2;
2065         ret = pkt_generic_packet(pd, &cgc);
2066         if (ret) {
2067                 pkt_dump_sense(&cgc);
2068                 return ret;
2069         }
2070         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2071         if (size > sizeof(buf))
2072                 size = sizeof(buf);
2073
2074         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2075         cgc.sense = &sense;
2076         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2077         cgc.cmd[1] = 2;
2078         cgc.cmd[2] = 4;
2079         cgc.cmd[8] = size;
2080         ret = pkt_generic_packet(pd, &cgc);
2081         if (ret) {
2082                 pkt_dump_sense(&cgc);
2083                 return ret;
2084         }
2085
2086         if (!(buf[6] & 0x40)) {
2087                 printk(DRIVER_NAME": Disc type is not CD-RW\n");
2088                 return 1;
2089         }
2090         if (!(buf[6] & 0x4)) {
2091                 printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2092                 return 1;
2093         }
2094
2095         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2096
2097         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2098
2099         /* Info from cdrecord */
2100         switch (st) {
2101                 case 0: /* standard speed */
2102                         *speed = clv_to_speed[sp];
2103                         break;
2104                 case 1: /* high speed */
2105                         *speed = hs_clv_to_speed[sp];
2106                         break;
2107                 case 2: /* ultra high speed */
2108                         *speed = us_clv_to_speed[sp];
2109                         break;
2110                 default:
2111                         printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2112                         return 1;
2113         }
2114         if (*speed) {
2115                 printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2116                 return 0;
2117         } else {
2118                 printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2119                 return 1;
2120         }
2121 }
2122
2123 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2124 {
2125         struct packet_command cgc;
2126         struct request_sense sense;
2127         int ret;
2128
2129         VPRINTK(DRIVER_NAME": Performing OPC\n");
2130
2131         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2132         cgc.sense = &sense;
2133         cgc.timeout = 60*HZ;
2134         cgc.cmd[0] = GPCMD_SEND_OPC;
2135         cgc.cmd[1] = 1;
2136         if ((ret = pkt_generic_packet(pd, &cgc)))
2137                 pkt_dump_sense(&cgc);
2138         return ret;
2139 }
2140
2141 static int pkt_open_write(struct pktcdvd_device *pd)
2142 {
2143         int ret;
2144         unsigned int write_speed, media_write_speed, read_speed;
2145
2146         if ((ret = pkt_probe_settings(pd))) {
2147                 VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2148                 return ret;
2149         }
2150
2151         if ((ret = pkt_set_write_settings(pd))) {
2152                 DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2153                 return -EIO;
2154         }
2155
2156         pkt_write_caching(pd, USE_WCACHING);
2157
2158         if ((ret = pkt_get_max_speed(pd, &write_speed)))
2159                 write_speed = 16 * 177;
2160         switch (pd->mmc3_profile) {
2161                 case 0x13: /* DVD-RW */
2162                 case 0x1a: /* DVD+RW */
2163                 case 0x12: /* DVD-RAM */
2164                         DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2165                         break;
2166                 default:
2167                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
2168                                 media_write_speed = 16;
2169                         write_speed = min(write_speed, media_write_speed * 177);
2170                         DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2171                         break;
2172         }
2173         read_speed = write_speed;
2174
2175         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2176                 DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2177                 return -EIO;
2178         }
2179         pd->write_speed = write_speed;
2180         pd->read_speed = read_speed;
2181
2182         if ((ret = pkt_perform_opc(pd))) {
2183                 DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2184         }
2185
2186         return 0;
2187 }
2188
2189 /*
2190  * called at open time.
2191  */
2192 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2193 {
2194         int ret;
2195         long lba;
2196         struct request_queue *q;
2197
2198         /*
2199          * We need to re-open the cdrom device without O_NONBLOCK to be able
2200          * to read/write from/to it. It is already opened in O_NONBLOCK mode
2201          * so bdget() can't fail.
2202          */
2203         bdget(pd->bdev->bd_dev);
2204         if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2205                 goto out;
2206
2207         if ((ret = pkt_get_last_written(pd, &lba))) {
2208                 printk(DRIVER_NAME": pkt_get_last_written failed\n");
2209                 goto out_putdev;
2210         }
2211
2212         set_capacity(pd->disk, lba << 2);
2213         set_capacity(pd->bdev->bd_disk, lba << 2);
2214         bd_set_size(pd->bdev, (loff_t)lba << 11);
2215
2216         q = bdev_get_queue(pd->bdev);
2217         if (write) {
2218                 if ((ret = pkt_open_write(pd)))
2219                         goto out_putdev;
2220                 /*
2221                  * Some CDRW drives can not handle writes larger than one packet,
2222                  * even if the size is a multiple of the packet size.
2223                  */
2224                 spin_lock_irq(q->queue_lock);
2225                 blk_queue_max_hw_sectors(q, pd->settings.size);
2226                 spin_unlock_irq(q->queue_lock);
2227                 set_bit(PACKET_WRITABLE, &pd->flags);
2228         } else {
2229                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2230                 clear_bit(PACKET_WRITABLE, &pd->flags);
2231         }
2232
2233         if ((ret = pkt_set_segment_merging(pd, q)))
2234                 goto out_putdev;
2235
2236         if (write) {
2237                 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2238                         printk(DRIVER_NAME": not enough memory for buffers\n");
2239                         ret = -ENOMEM;
2240                         goto out_putdev;
2241                 }
2242                 printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2243         }
2244
2245         return 0;
2246
2247 out_putdev:
2248         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2249 out:
2250         return ret;
2251 }
2252
2253 /*
2254  * called when the device is closed. makes sure that the device flushes
2255  * the internal cache before we close.
2256  */
2257 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2258 {
2259         if (flush && pkt_flush_cache(pd))
2260                 DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2261
2262         pkt_lock_door(pd, 0);
2263
2264         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2265         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2266
2267         pkt_shrink_pktlist(pd);
2268 }
2269
2270 static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2271 {
2272         if (dev_minor >= MAX_WRITERS)
2273                 return NULL;
2274         return pkt_devs[dev_minor];
2275 }
2276
2277 static int pkt_open(struct block_device *bdev, fmode_t mode)
2278 {
2279         struct pktcdvd_device *pd = NULL;
2280         int ret;
2281
2282         VPRINTK(DRIVER_NAME": entering open\n");
2283
2284         mutex_lock(&pktcdvd_mutex);
2285         mutex_lock(&ctl_mutex);
2286         pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2287         if (!pd) {
2288                 ret = -ENODEV;
2289                 goto out;
2290         }
2291         BUG_ON(pd->refcnt < 0);
2292
2293         pd->refcnt++;
2294         if (pd->refcnt > 1) {
2295                 if ((mode & FMODE_WRITE) &&
2296                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2297                         ret = -EBUSY;
2298                         goto out_dec;
2299                 }
2300         } else {
2301                 ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2302                 if (ret)
2303                         goto out_dec;
2304                 /*
2305                  * needed here as well, since ext2 (among others) may change
2306                  * the blocksize at mount time
2307                  */
2308                 set_blocksize(bdev, CD_FRAMESIZE);
2309         }
2310
2311         mutex_unlock(&ctl_mutex);
2312         mutex_unlock(&pktcdvd_mutex);
2313         return 0;
2314
2315 out_dec:
2316         pd->refcnt--;
2317 out:
2318         VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2319         mutex_unlock(&ctl_mutex);
2320         mutex_unlock(&pktcdvd_mutex);
2321         return ret;
2322 }
2323
2324 static void pkt_close(struct gendisk *disk, fmode_t mode)
2325 {
2326         struct pktcdvd_device *pd = disk->private_data;
2327
2328         mutex_lock(&pktcdvd_mutex);
2329         mutex_lock(&ctl_mutex);
2330         pd->refcnt--;
2331         BUG_ON(pd->refcnt < 0);
2332         if (pd->refcnt == 0) {
2333                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2334                 pkt_release_dev(pd, flush);
2335         }
2336         mutex_unlock(&ctl_mutex);
2337         mutex_unlock(&pktcdvd_mutex);
2338 }
2339
2340
2341 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2342 {
2343         struct packet_stacked_data *psd = bio->bi_private;
2344         struct pktcdvd_device *pd = psd->pd;
2345
2346         bio_put(bio);
2347         bio_endio(psd->bio, err);
2348         mempool_free(psd, psd_pool);
2349         pkt_bio_finished(pd);
2350 }
2351
2352 static void pkt_make_request(struct request_queue *q, struct bio *bio)
2353 {
2354         struct pktcdvd_device *pd;
2355         char b[BDEVNAME_SIZE];
2356         sector_t zone;
2357         struct packet_data *pkt;
2358         int was_empty, blocked_bio;
2359         struct pkt_rb_node *node;
2360
2361         pd = q->queuedata;
2362         if (!pd) {
2363                 printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2364                 goto end_io;
2365         }
2366
2367         /*
2368          * Clone READ bios so we can have our own bi_end_io callback.
2369          */
2370         if (bio_data_dir(bio) == READ) {
2371                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2372                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2373
2374                 psd->pd = pd;
2375                 psd->bio = bio;
2376                 cloned_bio->bi_bdev = pd->bdev;
2377                 cloned_bio->bi_private = psd;
2378                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2379                 pd->stats.secs_r += bio_sectors(bio);
2380                 pkt_queue_bio(pd, cloned_bio);
2381                 return;
2382         }
2383
2384         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2385                 printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2386                         pd->name, (unsigned long long)bio->bi_sector);
2387                 goto end_io;
2388         }
2389
2390         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2391                 printk(DRIVER_NAME": wrong bio size\n");
2392                 goto end_io;
2393         }
2394
2395         blk_queue_bounce(q, &bio);
2396
2397         zone = ZONE(bio->bi_sector, pd);
2398         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2399                 (unsigned long long)bio->bi_sector,
2400                 (unsigned long long)bio_end_sector(bio));
2401
2402         /* Check if we have to split the bio */
2403         {
2404                 struct bio_pair *bp;
2405                 sector_t last_zone;
2406                 int first_sectors;
2407
2408                 last_zone = ZONE(bio_end_sector(bio) - 1, pd);
2409                 if (last_zone != zone) {
2410                         BUG_ON(last_zone != zone + pd->settings.size);
2411                         first_sectors = last_zone - bio->bi_sector;
2412                         bp = bio_split(bio, first_sectors);
2413                         BUG_ON(!bp);
2414                         pkt_make_request(q, &bp->bio1);
2415                         pkt_make_request(q, &bp->bio2);
2416                         bio_pair_release(bp);
2417                         return;
2418                 }
2419         }
2420
2421         /*
2422          * If we find a matching packet in state WAITING or READ_WAIT, we can
2423          * just append this bio to that packet.
2424          */
2425         spin_lock(&pd->cdrw.active_list_lock);
2426         blocked_bio = 0;
2427         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2428                 if (pkt->sector == zone) {
2429                         spin_lock(&pkt->lock);
2430                         if ((pkt->state == PACKET_WAITING_STATE) ||
2431                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2432                                 bio_list_add(&pkt->orig_bios, bio);
2433                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2434                                 if ((pkt->write_size >= pkt->frames) &&
2435                                     (pkt->state == PACKET_WAITING_STATE)) {
2436                                         atomic_inc(&pkt->run_sm);
2437                                         wake_up(&pd->wqueue);
2438                                 }
2439                                 spin_unlock(&pkt->lock);
2440                                 spin_unlock(&pd->cdrw.active_list_lock);
2441                                 return;
2442                         } else {
2443                                 blocked_bio = 1;
2444                         }
2445                         spin_unlock(&pkt->lock);
2446                 }
2447         }
2448         spin_unlock(&pd->cdrw.active_list_lock);
2449
2450         /*
2451          * Test if there is enough room left in the bio work queue
2452          * (queue size >= congestion on mark).
2453          * If not, wait till the work queue size is below the congestion off mark.
2454          */
2455         spin_lock(&pd->lock);
2456         if (pd->write_congestion_on > 0
2457             && pd->bio_queue_size >= pd->write_congestion_on) {
2458                 set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2459                 do {
2460                         spin_unlock(&pd->lock);
2461                         congestion_wait(BLK_RW_ASYNC, HZ);
2462                         spin_lock(&pd->lock);
2463                 } while(pd->bio_queue_size > pd->write_congestion_off);
2464         }
2465         spin_unlock(&pd->lock);
2466
2467         /*
2468          * No matching packet found. Store the bio in the work queue.
2469          */
2470         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2471         node->bio = bio;
2472         spin_lock(&pd->lock);
2473         BUG_ON(pd->bio_queue_size < 0);
2474         was_empty = (pd->bio_queue_size == 0);
2475         pkt_rbtree_insert(pd, node);
2476         spin_unlock(&pd->lock);
2477
2478         /*
2479          * Wake up the worker thread.
2480          */
2481         atomic_set(&pd->scan_queue, 1);
2482         if (was_empty) {
2483                 /* This wake_up is required for correct operation */
2484                 wake_up(&pd->wqueue);
2485         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2486                 /*
2487                  * This wake up is not required for correct operation,
2488                  * but improves performance in some cases.
2489                  */
2490                 wake_up(&pd->wqueue);
2491         }
2492         return;
2493 end_io:
2494         bio_io_error(bio);
2495 }
2496
2497
2498
2499 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2500                           struct bio_vec *bvec)
2501 {
2502         struct pktcdvd_device *pd = q->queuedata;
2503         sector_t zone = ZONE(bmd->bi_sector, pd);
2504         int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2505         int remaining = (pd->settings.size << 9) - used;
2506         int remaining2;
2507
2508         /*
2509          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2510          * boundary, pkt_make_request() will split the bio.
2511          */
2512         remaining2 = PAGE_SIZE - bmd->bi_size;
2513         remaining = max(remaining, remaining2);
2514
2515         BUG_ON(remaining < 0);
2516         return remaining;
2517 }
2518
2519 static void pkt_init_queue(struct pktcdvd_device *pd)
2520 {
2521         struct request_queue *q = pd->disk->queue;
2522
2523         blk_queue_make_request(q, pkt_make_request);
2524         blk_queue_logical_block_size(q, CD_FRAMESIZE);
2525         blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2526         blk_queue_merge_bvec(q, pkt_merge_bvec);
2527         q->queuedata = pd;
2528 }
2529
2530 static int pkt_seq_show(struct seq_file *m, void *p)
2531 {
2532         struct pktcdvd_device *pd = m->private;
2533         char *msg;
2534         char bdev_buf[BDEVNAME_SIZE];
2535         int states[PACKET_NUM_STATES];
2536
2537         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2538                    bdevname(pd->bdev, bdev_buf));
2539
2540         seq_printf(m, "\nSettings:\n");
2541         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2542
2543         if (pd->settings.write_type == 0)
2544                 msg = "Packet";
2545         else
2546                 msg = "Unknown";
2547         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2548
2549         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2550         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2551
2552         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2553
2554         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2555                 msg = "Mode 1";
2556         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2557                 msg = "Mode 2";
2558         else
2559                 msg = "Unknown";
2560         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2561
2562         seq_printf(m, "\nStatistics:\n");
2563         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2564         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2565         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2566         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2567         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2568
2569         seq_printf(m, "\nMisc:\n");
2570         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2571         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2572         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2573         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2574         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2575         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2576
2577         seq_printf(m, "\nQueue state:\n");
2578         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2579         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2580         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2581
2582         pkt_count_states(pd, states);
2583         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2584                    states[0], states[1], states[2], states[3], states[4], states[5]);
2585
2586         seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2587                         pd->write_congestion_off,
2588                         pd->write_congestion_on);
2589         return 0;
2590 }
2591
2592 static int pkt_seq_open(struct inode *inode, struct file *file)
2593 {
2594         return single_open(file, pkt_seq_show, PDE_DATA(inode));
2595 }
2596
2597 static const struct file_operations pkt_proc_fops = {
2598         .open   = pkt_seq_open,
2599         .read   = seq_read,
2600         .llseek = seq_lseek,
2601         .release = single_release
2602 };
2603
2604 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2605 {
2606         int i;
2607         int ret = 0;
2608         char b[BDEVNAME_SIZE];
2609         struct block_device *bdev;
2610
2611         if (pd->pkt_dev == dev) {
2612                 printk(DRIVER_NAME": Recursive setup not allowed\n");
2613                 return -EBUSY;
2614         }
2615         for (i = 0; i < MAX_WRITERS; i++) {
2616                 struct pktcdvd_device *pd2 = pkt_devs[i];
2617                 if (!pd2)
2618                         continue;
2619                 if (pd2->bdev->bd_dev == dev) {
2620                         printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
2621                         return -EBUSY;
2622                 }
2623                 if (pd2->pkt_dev == dev) {
2624                         printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2625                         return -EBUSY;
2626                 }
2627         }
2628
2629         bdev = bdget(dev);
2630         if (!bdev)
2631                 return -ENOMEM;
2632         ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2633         if (ret)
2634                 return ret;
2635
2636         /* This is safe, since we have a reference from open(). */
2637         __module_get(THIS_MODULE);
2638
2639         pd->bdev = bdev;
2640         set_blocksize(bdev, CD_FRAMESIZE);
2641
2642         pkt_init_queue(pd);
2643
2644         atomic_set(&pd->cdrw.pending_bios, 0);
2645         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2646         if (IS_ERR(pd->cdrw.thread)) {
2647                 printk(DRIVER_NAME": can't start kernel thread\n");
2648                 ret = -ENOMEM;
2649                 goto out_mem;
2650         }
2651
2652         proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2653         DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2654         return 0;
2655
2656 out_mem:
2657         blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2658         /* This is safe: open() is still holding a reference. */
2659         module_put(THIS_MODULE);
2660         return ret;
2661 }
2662
2663 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2664 {
2665         struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2666         int ret;
2667
2668         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2669                 MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2670
2671         mutex_lock(&pktcdvd_mutex);
2672         switch (cmd) {
2673         case CDROMEJECT:
2674                 /*
2675                  * The door gets locked when the device is opened, so we
2676                  * have to unlock it or else the eject command fails.
2677                  */
2678                 if (pd->refcnt == 1)
2679                         pkt_lock_door(pd, 0);
2680                 /* fallthru */
2681         /*
2682          * forward selected CDROM ioctls to CD-ROM, for UDF
2683          */
2684         case CDROMMULTISESSION:
2685         case CDROMREADTOCENTRY:
2686         case CDROM_LAST_WRITTEN:
2687         case CDROM_SEND_PACKET:
2688         case SCSI_IOCTL_SEND_COMMAND:
2689                 ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2690                 break;
2691
2692         default:
2693                 VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2694                 ret = -ENOTTY;
2695         }
2696         mutex_unlock(&pktcdvd_mutex);
2697
2698         return ret;
2699 }
2700
2701 static unsigned int pkt_check_events(struct gendisk *disk,
2702                                      unsigned int clearing)
2703 {
2704         struct pktcdvd_device *pd = disk->private_data;
2705         struct gendisk *attached_disk;
2706
2707         if (!pd)
2708                 return 0;
2709         if (!pd->bdev)
2710                 return 0;
2711         attached_disk = pd->bdev->bd_disk;
2712         if (!attached_disk || !attached_disk->fops->check_events)
2713                 return 0;
2714         return attached_disk->fops->check_events(attached_disk, clearing);
2715 }
2716
2717 static const struct block_device_operations pktcdvd_ops = {
2718         .owner =                THIS_MODULE,
2719         .open =                 pkt_open,
2720         .release =              pkt_close,
2721         .ioctl =                pkt_ioctl,
2722         .check_events =         pkt_check_events,
2723 };
2724
2725 static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
2726 {
2727         return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2728 }
2729
2730 /*
2731  * Set up mapping from pktcdvd device to CD-ROM device.
2732  */
2733 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2734 {
2735         int idx;
2736         int ret = -ENOMEM;
2737         struct pktcdvd_device *pd;
2738         struct gendisk *disk;
2739
2740         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2741
2742         for (idx = 0; idx < MAX_WRITERS; idx++)
2743                 if (!pkt_devs[idx])
2744                         break;
2745         if (idx == MAX_WRITERS) {
2746                 printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2747                 ret = -EBUSY;
2748                 goto out_mutex;
2749         }
2750
2751         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2752         if (!pd)
2753                 goto out_mutex;
2754
2755         pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2756                                                   sizeof(struct pkt_rb_node));
2757         if (!pd->rb_pool)
2758                 goto out_mem;
2759
2760         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2761         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2762         spin_lock_init(&pd->cdrw.active_list_lock);
2763
2764         spin_lock_init(&pd->lock);
2765         spin_lock_init(&pd->iosched.lock);
2766         bio_list_init(&pd->iosched.read_queue);
2767         bio_list_init(&pd->iosched.write_queue);
2768         sprintf(pd->name, DRIVER_NAME"%d", idx);
2769         init_waitqueue_head(&pd->wqueue);
2770         pd->bio_queue = RB_ROOT;
2771
2772         pd->write_congestion_on  = write_congestion_on;
2773         pd->write_congestion_off = write_congestion_off;
2774
2775         disk = alloc_disk(1);
2776         if (!disk)
2777                 goto out_mem;
2778         pd->disk = disk;
2779         disk->major = pktdev_major;
2780         disk->first_minor = idx;
2781         disk->fops = &pktcdvd_ops;
2782         disk->flags = GENHD_FL_REMOVABLE;
2783         strcpy(disk->disk_name, pd->name);
2784         disk->devnode = pktcdvd_devnode;
2785         disk->private_data = pd;
2786         disk->queue = blk_alloc_queue(GFP_KERNEL);
2787         if (!disk->queue)
2788                 goto out_mem2;
2789
2790         pd->pkt_dev = MKDEV(pktdev_major, idx);
2791         ret = pkt_new_dev(pd, dev);
2792         if (ret)
2793                 goto out_new_dev;
2794
2795         /* inherit events of the host device */
2796         disk->events = pd->bdev->bd_disk->events;
2797         disk->async_events = pd->bdev->bd_disk->async_events;
2798
2799         add_disk(disk);
2800
2801         pkt_sysfs_dev_new(pd);
2802         pkt_debugfs_dev_new(pd);
2803
2804         pkt_devs[idx] = pd;
2805         if (pkt_dev)
2806                 *pkt_dev = pd->pkt_dev;
2807
2808         mutex_unlock(&ctl_mutex);
2809         return 0;
2810
2811 out_new_dev:
2812         blk_cleanup_queue(disk->queue);
2813 out_mem2:
2814         put_disk(disk);
2815 out_mem:
2816         if (pd->rb_pool)
2817                 mempool_destroy(pd->rb_pool);
2818         kfree(pd);
2819 out_mutex:
2820         mutex_unlock(&ctl_mutex);
2821         printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2822         return ret;
2823 }
2824
2825 /*
2826  * Tear down mapping from pktcdvd device to CD-ROM device.
2827  */
2828 static int pkt_remove_dev(dev_t pkt_dev)
2829 {
2830         struct pktcdvd_device *pd;
2831         int idx;
2832         int ret = 0;
2833
2834         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2835
2836         for (idx = 0; idx < MAX_WRITERS; idx++) {
2837                 pd = pkt_devs[idx];
2838                 if (pd && (pd->pkt_dev == pkt_dev))
2839                         break;
2840         }
2841         if (idx == MAX_WRITERS) {
2842                 DPRINTK(DRIVER_NAME": dev not setup\n");
2843                 ret = -ENXIO;
2844                 goto out;
2845         }
2846
2847         if (pd->refcnt > 0) {
2848                 ret = -EBUSY;
2849                 goto out;
2850         }
2851         if (!IS_ERR(pd->cdrw.thread))
2852                 kthread_stop(pd->cdrw.thread);
2853
2854         pkt_devs[idx] = NULL;
2855
2856         pkt_debugfs_dev_remove(pd);
2857         pkt_sysfs_dev_remove(pd);
2858
2859         blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2860
2861         remove_proc_entry(pd->name, pkt_proc);
2862         DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2863
2864         del_gendisk(pd->disk);
2865         blk_cleanup_queue(pd->disk->queue);
2866         put_disk(pd->disk);
2867
2868         mempool_destroy(pd->rb_pool);
2869         kfree(pd);
2870
2871         /* This is safe: open() is still holding a reference. */
2872         module_put(THIS_MODULE);
2873
2874 out:
2875         mutex_unlock(&ctl_mutex);
2876         return ret;
2877 }
2878
2879 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2880 {
2881         struct pktcdvd_device *pd;
2882
2883         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2884
2885         pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2886         if (pd) {
2887                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2888                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2889         } else {
2890                 ctrl_cmd->dev = 0;
2891                 ctrl_cmd->pkt_dev = 0;
2892         }
2893         ctrl_cmd->num_devices = MAX_WRITERS;
2894
2895         mutex_unlock(&ctl_mutex);
2896 }
2897
2898 static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2899 {
2900         void __user *argp = (void __user *)arg;
2901         struct pkt_ctrl_command ctrl_cmd;
2902         int ret = 0;
2903         dev_t pkt_dev = 0;
2904
2905         if (cmd != PACKET_CTRL_CMD)
2906                 return -ENOTTY;
2907
2908         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2909                 return -EFAULT;
2910
2911         switch (ctrl_cmd.command) {
2912         case PKT_CTRL_CMD_SETUP:
2913                 if (!capable(CAP_SYS_ADMIN))
2914                         return -EPERM;
2915                 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2916                 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2917                 break;
2918         case PKT_CTRL_CMD_TEARDOWN:
2919                 if (!capable(CAP_SYS_ADMIN))
2920                         return -EPERM;
2921                 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2922                 break;
2923         case PKT_CTRL_CMD_STATUS:
2924                 pkt_get_status(&ctrl_cmd);
2925                 break;
2926         default:
2927                 return -ENOTTY;
2928         }
2929
2930         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2931                 return -EFAULT;
2932         return ret;
2933 }
2934
2935 #ifdef CONFIG_COMPAT
2936 static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2937 {
2938         return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2939 }
2940 #endif
2941
2942 static const struct file_operations pkt_ctl_fops = {
2943         .open           = nonseekable_open,
2944         .unlocked_ioctl = pkt_ctl_ioctl,
2945 #ifdef CONFIG_COMPAT
2946         .compat_ioctl   = pkt_ctl_compat_ioctl,
2947 #endif
2948         .owner          = THIS_MODULE,
2949         .llseek         = no_llseek,
2950 };
2951
2952 static struct miscdevice pkt_misc = {
2953         .minor          = MISC_DYNAMIC_MINOR,
2954         .name           = DRIVER_NAME,
2955         .nodename       = "pktcdvd/control",
2956         .fops           = &pkt_ctl_fops
2957 };
2958
2959 static int __init pkt_init(void)
2960 {
2961         int ret;
2962
2963         mutex_init(&ctl_mutex);
2964
2965         psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
2966                                         sizeof(struct packet_stacked_data));
2967         if (!psd_pool)
2968                 return -ENOMEM;
2969
2970         ret = register_blkdev(pktdev_major, DRIVER_NAME);
2971         if (ret < 0) {
2972                 printk(DRIVER_NAME": Unable to register block device\n");
2973                 goto out2;
2974         }
2975         if (!pktdev_major)
2976                 pktdev_major = ret;
2977
2978         ret = pkt_sysfs_init();
2979         if (ret)
2980                 goto out;
2981
2982         pkt_debugfs_init();
2983
2984         ret = misc_register(&pkt_misc);
2985         if (ret) {
2986                 printk(DRIVER_NAME": Unable to register misc device\n");
2987                 goto out_misc;
2988         }
2989
2990         pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
2991
2992         return 0;
2993
2994 out_misc:
2995         pkt_debugfs_cleanup();
2996         pkt_sysfs_cleanup();
2997 out:
2998         unregister_blkdev(pktdev_major, DRIVER_NAME);
2999 out2:
3000         mempool_destroy(psd_pool);
3001         return ret;
3002 }
3003
3004 static void __exit pkt_exit(void)
3005 {
3006         remove_proc_entry("driver/"DRIVER_NAME, NULL);
3007         misc_deregister(&pkt_misc);
3008
3009         pkt_debugfs_cleanup();
3010         pkt_sysfs_cleanup();
3011
3012         unregister_blkdev(pktdev_major, DRIVER_NAME);
3013         mempool_destroy(psd_pool);
3014 }
3015
3016 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3017 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3018 MODULE_LICENSE("GPL");
3019
3020 module_init(pkt_init);
3021 module_exit(pkt_exit);