]> git.proxmox.com Git - mirror_ubuntu-artful-kernel.git/blob - drivers/block/pktcdvd.c
projects / mirror_ubuntu-artful-kernel.git / blob
? search:


4c20c228184c321694f8b1e408f50afecc0b07ba
[mirror_ubuntu-artful-kernel.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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
48
49 #include <linux/pktcdvd.h>
50 #include <linux/module.h>
51 #include <linux/types.h>
52 #include <linux/kernel.h>
53 #include <linux/compat.h>
54 #include <linux/kthread.h>
55 #include <linux/errno.h>
56 #include <linux/spinlock.h>
57 #include <linux/file.h>
58 #include <linux/proc_fs.h>
59 #include <linux/seq_file.h>
60 #include <linux/miscdevice.h>
61 #include <linux/freezer.h>
62 #include <linux/mutex.h>
63 #include <linux/slab.h>
64 #include <linux/backing-dev.h>
65 #include <scsi/scsi_cmnd.h>
66 #include <scsi/scsi_ioctl.h>
67 #include <scsi/scsi.h>
68 #include <linux/debugfs.h>
69 #include <linux/device.h>
70
71 #include <asm/uaccess.h>
72
73 #define DRIVER_NAME "pktcdvd"
74
75 #define pkt_err(pd, fmt, ...) \
76 pr_err("%s: " fmt, pd->name, ##__VA_ARGS__)
77 #define pkt_notice(pd, fmt, ...) \
78 pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__)
79 #define pkt_info(pd, fmt, ...) \
80 pr_info("%s: " fmt, pd->name, ##__VA_ARGS__)
81
82 #define pkt_dbg(level, pd, fmt, ...) \
83 do { \
84 if (level == 2 && PACKET_DEBUG >= 2) \
85 pr_notice("%s: %s():" fmt, \
86 pd->name, __func__, ##__VA_ARGS__); \
87 else if (level == 1 && PACKET_DEBUG >= 1) \
88 pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__); \
89 } while (0)
90
91 #define MAX_SPEED 0xffff
92
93 static DEFINE_MUTEX(pktcdvd_mutex);
94 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
95 static struct proc_dir_entry *pkt_proc;
96 static int pktdev_major;
97 static int write_congestion_on = PKT_WRITE_CONGESTION_ON;
98 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
99 static struct mutex ctl_mutex; /* Serialize open/close/setup/teardown */
100 static mempool_t *psd_pool;
101
102 static struct class *class_pktcdvd = NULL; /* /sys/class/pktcdvd */
103 static struct dentry *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
104
105 /* forward declaration */
106 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
107 static int pkt_remove_dev(dev_t pkt_dev);
108 static int pkt_seq_show(struct seq_file *m, void *p);
109
110 static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
111 {
112 return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1);
113 }
114
115 /*
116 * create and register a pktcdvd kernel object.
117 */
118 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
119 const char* name,
120 struct kobject* parent,
121 struct kobj_type* ktype)
122 {
123 struct pktcdvd_kobj *p;
124 int error;
125
126 p = kzalloc(sizeof(*p), GFP_KERNEL);
127 if (!p)
128 return NULL;
129 p->pd = pd;
130 error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
131 if (error) {
132 kobject_put(&p->kobj);
133 return NULL;
134 }
135 kobject_uevent(&p->kobj, KOBJ_ADD);
136 return p;
137 }
138 /*
139 * remove a pktcdvd kernel object.
140 */
141 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
142 {
143 if (p)
144 kobject_put(&p->kobj);
145 }
146 /*
147 * default release function for pktcdvd kernel objects.
148 */
149 static void pkt_kobj_release(struct kobject *kobj)
150 {
151 kfree(to_pktcdvdkobj(kobj));
152 }
153
154
155 /**********************************************************
156 *
157 * sysfs interface for pktcdvd
158 * by (C) 2006 Thomas Maier <balagi@justmail.de>
159 *
160 **********************************************************/
161
162 #define DEF_ATTR(_obj,_name,_mode) \
163 static struct attribute _obj = { .name = _name, .mode = _mode }
164
165 /**********************************************************
166 /sys/class/pktcdvd/pktcdvd[0-7]/
167 stat/reset
168 stat/packets_started
169 stat/packets_finished
170 stat/kb_written
171 stat/kb_read
172 stat/kb_read_gather
173 write_queue/size
174 write_queue/congestion_off
175 write_queue/congestion_on
176 **********************************************************/
177
178 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
179 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
180 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
181 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
182 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
183 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
184
185 static struct attribute *kobj_pkt_attrs_stat[] = {
186 &kobj_pkt_attr_st1,
187 &kobj_pkt_attr_st2,
188 &kobj_pkt_attr_st3,
189 &kobj_pkt_attr_st4,
190 &kobj_pkt_attr_st5,
191 &kobj_pkt_attr_st6,
192 NULL
193 };
194
195 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
196 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
197 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on", 0644);
198
199 static struct attribute *kobj_pkt_attrs_wqueue[] = {
200 &kobj_pkt_attr_wq1,
201 &kobj_pkt_attr_wq2,
202 &kobj_pkt_attr_wq3,
203 NULL
204 };
205
206 static ssize_t kobj_pkt_show(struct kobject *kobj,
207 struct attribute *attr, char *data)
208 {
209 struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
210 int n = 0;
211 int v;
212 if (strcmp(attr->name, "packets_started") == 0) {
213 n = sprintf(data, "%lu\n", pd->stats.pkt_started);
214
215 } else if (strcmp(attr->name, "packets_finished") == 0) {
216 n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
217
218 } else if (strcmp(attr->name, "kb_written") == 0) {
219 n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
220
221 } else if (strcmp(attr->name, "kb_read") == 0) {
222 n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
223
224 } else if (strcmp(attr->name, "kb_read_gather") == 0) {
225 n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
226
227 } else if (strcmp(attr->name, "size") == 0) {
228 spin_lock(&pd->lock);
229 v = pd->bio_queue_size;
230 spin_unlock(&pd->lock);
231 n = sprintf(data, "%d\n", v);
232
233 } else if (strcmp(attr->name, "congestion_off") == 0) {
234 spin_lock(&pd->lock);
235 v = pd->write_congestion_off;
236 spin_unlock(&pd->lock);
237 n = sprintf(data, "%d\n", v);
238
239 } else if (strcmp(attr->name, "congestion_on") == 0) {
240 spin_lock(&pd->lock);
241 v = pd->write_congestion_on;
242 spin_unlock(&pd->lock);
243 n = sprintf(data, "%d\n", v);
244 }
245 return n;
246 }
247
248 static void init_write_congestion_marks(int* lo, int* hi)
249 {
250 if (*hi > 0) {
251 *hi = max(*hi, 500);
252 *hi = min(*hi, 1000000);
253 if (*lo <= 0)
254 *lo = *hi - 100;
255 else {
256 *lo = min(*lo, *hi - 100);
257 *lo = max(*lo, 100);
258 }
259 } else {
260 *hi = -1;
261 *lo = -1;
262 }
263 }
264
265 static ssize_t kobj_pkt_store(struct kobject *kobj,
266 struct attribute *attr,
267 const char *data, size_t len)
268 {
269 struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
270 int val;
271
272 if (strcmp(attr->name, "reset") == 0 && len > 0) {
273 pd->stats.pkt_started = 0;
274 pd->stats.pkt_ended = 0;
275 pd->stats.secs_w = 0;
276 pd->stats.secs_rg = 0;
277 pd->stats.secs_r = 0;
278
279 } else if (strcmp(attr->name, "congestion_off") == 0
280 && sscanf(data, "%d", &val) == 1) {
281 spin_lock(&pd->lock);
282 pd->write_congestion_off = val;
283 init_write_congestion_marks(&pd->write_congestion_off,
284 &pd->write_congestion_on);
285 spin_unlock(&pd->lock);
286
287 } else if (strcmp(attr->name, "congestion_on") == 0
288 && sscanf(data, "%d", &val) == 1) {
289 spin_lock(&pd->lock);
290 pd->write_congestion_on = val;
291 init_write_congestion_marks(&pd->write_congestion_off,
292 &pd->write_congestion_on);
293 spin_unlock(&pd->lock);
294 }
295 return len;
296 }
297
298 static const struct sysfs_ops kobj_pkt_ops = {
299 .show = kobj_pkt_show,
300 .store = kobj_pkt_store
301 };
302 static struct kobj_type kobj_pkt_type_stat = {
303 .release = pkt_kobj_release,
304 .sysfs_ops = &kobj_pkt_ops,
305 .default_attrs = kobj_pkt_attrs_stat
306 };
307 static struct kobj_type kobj_pkt_type_wqueue = {
308 .release = pkt_kobj_release,
309 .sysfs_ops = &kobj_pkt_ops,
310 .default_attrs = kobj_pkt_attrs_wqueue
311 };
312
313 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
314 {
315 if (class_pktcdvd) {
316 pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
317 "%s", pd->name);
318 if (IS_ERR(pd->dev))
319 pd->dev = NULL;
320 }
321 if (pd->dev) {
322 pd->kobj_stat = pkt_kobj_create(pd, "stat",
323 &pd->dev->kobj,
324 &kobj_pkt_type_stat);
325 pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
326 &pd->dev->kobj,
327 &kobj_pkt_type_wqueue);
328 }
329 }
330
331 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
332 {
333 pkt_kobj_remove(pd->kobj_stat);
334 pkt_kobj_remove(pd->kobj_wqueue);
335 if (class_pktcdvd)
336 device_unregister(pd->dev);
337 }
338
339
340 /********************************************************************
341 /sys/class/pktcdvd/
342 add map block device
343 remove unmap packet dev
344 device_map show mappings
345 *******************************************************************/
346
347 static void class_pktcdvd_release(struct class *cls)
348 {
349 kfree(cls);
350 }
351 static ssize_t class_pktcdvd_show_map(struct class *c,
352 struct class_attribute *attr,
353 char *data)
354 {
355 int n = 0;
356 int idx;
357 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
358 for (idx = 0; idx < MAX_WRITERS; idx++) {
359 struct pktcdvd_device *pd = pkt_devs[idx];
360 if (!pd)
361 continue;
362 n += sprintf(data+n, "%s %u:%u %u:%u\n",
363 pd->name,
364 MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
365 MAJOR(pd->bdev->bd_dev),
366 MINOR(pd->bdev->bd_dev));
367 }
368 mutex_unlock(&ctl_mutex);
369 return n;
370 }
371
372 static ssize_t class_pktcdvd_store_add(struct class *c,
373 struct class_attribute *attr,
374 const char *buf,
375 size_t count)
376 {
377 unsigned int major, minor;
378
379 if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
380 /* pkt_setup_dev() expects caller to hold reference to self */
381 if (!try_module_get(THIS_MODULE))
382 return -ENODEV;
383
384 pkt_setup_dev(MKDEV(major, minor), NULL);
385
386 module_put(THIS_MODULE);
387
388 return count;
389 }
390
391 return -EINVAL;
392 }
393
394 static ssize_t class_pktcdvd_store_remove(struct class *c,
395 struct class_attribute *attr,
396 const char *buf,
397 size_t count)
398 {
399 unsigned int major, minor;
400 if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
401 pkt_remove_dev(MKDEV(major, minor));
402 return count;
403 }
404 return -EINVAL;
405 }
406
407 static struct class_attribute class_pktcdvd_attrs[] = {
408 __ATTR(add, 0200, NULL, class_pktcdvd_store_add),
409 __ATTR(remove, 0200, NULL, class_pktcdvd_store_remove),
410 __ATTR(device_map, 0444, class_pktcdvd_show_map, NULL),
411 __ATTR_NULL
412 };
413
414
415 static int pkt_sysfs_init(void)
416 {
417 int ret = 0;
418
419 /*
420 * create control files in sysfs
421 * /sys/class/pktcdvd/...
422 */
423 class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
424 if (!class_pktcdvd)
425 return -ENOMEM;
426 class_pktcdvd->name = DRIVER_NAME;
427 class_pktcdvd->owner = THIS_MODULE;
428 class_pktcdvd->class_release = class_pktcdvd_release;
429 class_pktcdvd->class_attrs = class_pktcdvd_attrs;
430 ret = class_register(class_pktcdvd);
431 if (ret) {
432 kfree(class_pktcdvd);
433 class_pktcdvd = NULL;
434 pr_err("failed to create class pktcdvd\n");
435 return ret;
436 }
437 return 0;
438 }
439
440 static void pkt_sysfs_cleanup(void)
441 {
442 if (class_pktcdvd)
443 class_destroy(class_pktcdvd);
444 class_pktcdvd = NULL;
445 }
446
447 /********************************************************************
448 entries in debugfs
449
450 /sys/kernel/debug/pktcdvd[0-7]/
451 info
452
453 *******************************************************************/
454
455 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
456 {
457 return pkt_seq_show(m, p);
458 }
459
460 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
461 {
462 return single_open(file, pkt_debugfs_seq_show, inode->i_private);
463 }
464
465 static const struct file_operations debug_fops = {
466 .open = pkt_debugfs_fops_open,
467 .read = seq_read,
468 .llseek = seq_lseek,
469 .release = single_release,
470 .owner = THIS_MODULE,
471 };
472
473 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
474 {
475 if (!pkt_debugfs_root)
476 return;
477 pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
478 if (!pd->dfs_d_root)
479 return;
480
481 pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
482 pd->dfs_d_root, pd, &debug_fops);
483 }
484
485 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
486 {
487 if (!pkt_debugfs_root)
488 return;
489 debugfs_remove(pd->dfs_f_info);
490 debugfs_remove(pd->dfs_d_root);
491 pd->dfs_f_info = NULL;
492 pd->dfs_d_root = NULL;
493 }
494
495 static void pkt_debugfs_init(void)
496 {
497 pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
498 }
499
500 static void pkt_debugfs_cleanup(void)
501 {
502 debugfs_remove(pkt_debugfs_root);
503 pkt_debugfs_root = NULL;
504 }
505
506 /* ----------------------------------------------------------*/
507
508
509 static void pkt_bio_finished(struct pktcdvd_device *pd)
510 {
511 BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
512 if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
513 pkt_dbg(2, pd, "queue empty\n");
514 atomic_set(&pd->iosched.attention, 1);
515 wake_up(&pd->wqueue);
516 }
517 }
518
519 /*
520 * Allocate a packet_data struct
521 */
522 static struct packet_data *pkt_alloc_packet_data(int frames)
523 {
524 int i;
525 struct packet_data *pkt;
526
527 pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
528 if (!pkt)
529 goto no_pkt;
530
531 pkt->frames = frames;
532 pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
533 if (!pkt->w_bio)
534 goto no_bio;
535
536 for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
537 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
538 if (!pkt->pages[i])
539 goto no_page;
540 }
541
542 spin_lock_init(&pkt->lock);
543 bio_list_init(&pkt->orig_bios);
544
545 for (i = 0; i < frames; i++) {
546 struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
547 if (!bio)
548 goto no_rd_bio;
549
550 pkt->r_bios[i] = bio;
551 }
552
553 return pkt;
554
555 no_rd_bio:
556 for (i = 0; i < frames; i++) {
557 struct bio *bio = pkt->r_bios[i];
558 if (bio)
559 bio_put(bio);
560 }
561
562 no_page:
563 for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
564 if (pkt->pages[i])
565 __free_page(pkt->pages[i]);
566 bio_put(pkt->w_bio);
567 no_bio:
568 kfree(pkt);
569 no_pkt:
570 return NULL;
571 }
572
573 /*
574 * Free a packet_data struct
575 */
576 static void pkt_free_packet_data(struct packet_data *pkt)
577 {
578 int i;
579
580 for (i = 0; i < pkt->frames; i++) {
581 struct bio *bio = pkt->r_bios[i];
582 if (bio)
583 bio_put(bio);
584 }
585 for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
586 __free_page(pkt->pages[i]);
587 bio_put(pkt->w_bio);
588 kfree(pkt);
589 }
590
591 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
592 {
593 struct packet_data *pkt, *next;
594
595 BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
596
597 list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
598 pkt_free_packet_data(pkt);
599 }
600 INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
601 }
602
603 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
604 {
605 struct packet_data *pkt;
606
607 BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
608
609 while (nr_packets > 0) {
610 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
611 if (!pkt) {
612 pkt_shrink_pktlist(pd);
613 return 0;
614 }
615 pkt->id = nr_packets;
616 pkt->pd = pd;
617 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
618 nr_packets--;
619 }
620 return 1;
621 }
622
623 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
624 {
625 struct rb_node *n = rb_next(&node->rb_node);
626 if (!n)
627 return NULL;
628 return rb_entry(n, struct pkt_rb_node, rb_node);
629 }
630
631 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
632 {
633 rb_erase(&node->rb_node, &pd->bio_queue);
634 mempool_free(node, pd->rb_pool);
635 pd->bio_queue_size--;
636 BUG_ON(pd->bio_queue_size < 0);
637 }
638
639 /*
640 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
641 */
642 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
643 {
644 struct rb_node *n = pd->bio_queue.rb_node;
645 struct rb_node *next;
646 struct pkt_rb_node *tmp;
647
648 if (!n) {
649 BUG_ON(pd->bio_queue_size > 0);
650 return NULL;
651 }
652
653 for (;;) {
654 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
655 if (s <= tmp->bio->bi_iter.bi_sector)
656 next = n->rb_left;
657 else
658 next = n->rb_right;
659 if (!next)
660 break;
661 n = next;
662 }
663
664 if (s > tmp->bio->bi_iter.bi_sector) {
665 tmp = pkt_rbtree_next(tmp);
666 if (!tmp)
667 return NULL;
668 }
669 BUG_ON(s > tmp->bio->bi_iter.bi_sector);
670 return tmp;
671 }
672
673 /*
674 * Insert a node into the pd->bio_queue rb tree.
675 */
676 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
677 {
678 struct rb_node **p = &pd->bio_queue.rb_node;
679 struct rb_node *parent = NULL;
680 sector_t s = node->bio->bi_iter.bi_sector;
681 struct pkt_rb_node *tmp;
682
683 while (*p) {
684 parent = *p;
685 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
686 if (s < tmp->bio->bi_iter.bi_sector)
687 p = &(*p)->rb_left;
688 else
689 p = &(*p)->rb_right;
690 }
691 rb_link_node(&node->rb_node, parent, p);
692 rb_insert_color(&node->rb_node, &pd->bio_queue);
693 pd->bio_queue_size++;
694 }
695
696 /*
697 * Send a packet_command to the underlying block device and
698 * wait for completion.
699 */
700 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
701 {
702 struct request_queue *q = bdev_get_queue(pd->bdev);
703 struct request *rq;
704 int ret = 0;
705
706 rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
707 WRITE : READ, __GFP_WAIT);
708 if (IS_ERR(rq))
709 return PTR_ERR(rq);
710 blk_rq_set_block_pc(rq);
711
712 if (cgc->buflen) {
713 ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
714 __GFP_WAIT);
715 if (ret)
716 goto out;
717 }
718
719 rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
720 memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
721
722 rq->timeout = 60*HZ;
723 if (cgc->quiet)
724 rq->cmd_flags |= REQ_QUIET;
725
726 blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
727 if (rq->errors)
728 ret = -EIO;
729 out:
730 blk_put_request(rq);
731 return ret;
732 }
733
734 static const char *sense_key_string(__u8 index)
735 {
736 static const char * const info[] = {
737 "No sense", "Recovered error", "Not ready",
738 "Medium error", "Hardware error", "Illegal request",
739 "Unit attention", "Data protect", "Blank check",
740 };
741
742 return index < ARRAY_SIZE(info) ? info[index] : "INVALID";
743 }
744
745 /*
746 * A generic sense dump / resolve mechanism should be implemented across
747 * all ATAPI + SCSI devices.
748 */
749 static void pkt_dump_sense(struct pktcdvd_device *pd,
750 struct packet_command *cgc)
751 {
752 struct request_sense *sense = cgc->sense;
753
754 if (sense)
755 pkt_err(pd, "%*ph - sense %02x.%02x.%02x (%s)\n",
756 CDROM_PACKET_SIZE, cgc->cmd,
757 sense->sense_key, sense->asc, sense->ascq,
758 sense_key_string(sense->sense_key));
759 else
760 pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
761 }
762
763 /*
764 * flush the drive cache to media
765 */
766 static int pkt_flush_cache(struct pktcdvd_device *pd)
767 {
768 struct packet_command cgc;
769
770 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
771 cgc.cmd[0] = GPCMD_FLUSH_CACHE;
772 cgc.quiet = 1;
773
774 /*
775 * the IMMED bit -- we default to not setting it, although that
776 * would allow a much faster close, this is safer
777 */
778 #if 0
779 cgc.cmd[1] = 1 << 1;
780 #endif
781 return pkt_generic_packet(pd, &cgc);
782 }
783
784 /*
785 * speed is given as the normal factor, e.g. 4 for 4x
786 */
787 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
788 unsigned write_speed, unsigned read_speed)
789 {
790 struct packet_command cgc;
791 struct request_sense sense;
792 int ret;
793
794 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
795 cgc.sense = &sense;
796 cgc.cmd[0] = GPCMD_SET_SPEED;
797 cgc.cmd[2] = (read_speed >> 8) & 0xff;
798 cgc.cmd[3] = read_speed & 0xff;
799 cgc.cmd[4] = (write_speed >> 8) & 0xff;
800 cgc.cmd[5] = write_speed & 0xff;
801
802 if ((ret = pkt_generic_packet(pd, &cgc)))
803 pkt_dump_sense(pd, &cgc);
804
805 return ret;
806 }
807
808 /*
809 * Queue a bio for processing by the low-level CD device. Must be called
810 * from process context.
811 */
812 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
813 {
814 spin_lock(&pd->iosched.lock);
815 if (bio_data_dir(bio) == READ)
816 bio_list_add(&pd->iosched.read_queue, bio);
817 else
818 bio_list_add(&pd->iosched.write_queue, bio);
819 spin_unlock(&pd->iosched.lock);
820
821 atomic_set(&pd->iosched.attention, 1);
822 wake_up(&pd->wqueue);
823 }
824
825 /*
826 * Process the queued read/write requests. This function handles special
827 * requirements for CDRW drives:
828 * - A cache flush command must be inserted before a read request if the
829 * previous request was a write.
830 * - Switching between reading and writing is slow, so don't do it more often
831 * than necessary.
832 * - Optimize for throughput at the expense of latency. This means that streaming
833 * writes will never be interrupted by a read, but if the drive has to seek
834 * before the next write, switch to reading instead if there are any pending
835 * read requests.
836 * - Set the read speed according to current usage pattern. When only reading
837 * from the device, it's best to use the highest possible read speed, but
838 * when switching often between reading and writing, it's better to have the
839 * same read and write speeds.
840 */
841 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
842 {
843
844 if (atomic_read(&pd->iosched.attention) == 0)
845 return;
846 atomic_set(&pd->iosched.attention, 0);
847
848 for (;;) {
849 struct bio *bio;
850 int reads_queued, writes_queued;
851
852 spin_lock(&pd->iosched.lock);
853 reads_queued = !bio_list_empty(&pd->iosched.read_queue);
854 writes_queued = !bio_list_empty(&pd->iosched.write_queue);
855 spin_unlock(&pd->iosched.lock);
856
857 if (!reads_queued && !writes_queued)
858 break;
859
860 if (pd->iosched.writing) {
861 int need_write_seek = 1;
862 spin_lock(&pd->iosched.lock);
863 bio = bio_list_peek(&pd->iosched.write_queue);
864 spin_unlock(&pd->iosched.lock);
865 if (bio && (bio->bi_iter.bi_sector ==
866 pd->iosched.last_write))
867 need_write_seek = 0;
868 if (need_write_seek && reads_queued) {
869 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
870 pkt_dbg(2, pd, "write, waiting\n");
871 break;
872 }
873 pkt_flush_cache(pd);
874 pd->iosched.writing = 0;
875 }
876 } else {
877 if (!reads_queued && writes_queued) {
878 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
879 pkt_dbg(2, pd, "read, waiting\n");
880 break;
881 }
882 pd->iosched.writing = 1;
883 }
884 }
885
886 spin_lock(&pd->iosched.lock);
887 if (pd->iosched.writing)
888 bio = bio_list_pop(&pd->iosched.write_queue);
889 else
890 bio = bio_list_pop(&pd->iosched.read_queue);
891 spin_unlock(&pd->iosched.lock);
892
893 if (!bio)
894 continue;
895
896 if (bio_data_dir(bio) == READ)
897 pd->iosched.successive_reads +=
898 bio->bi_iter.bi_size >> 10;
899 else {
900 pd->iosched.successive_reads = 0;
901 pd->iosched.last_write = bio_end_sector(bio);
902 }
903 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
904 if (pd->read_speed == pd->write_speed) {
905 pd->read_speed = MAX_SPEED;
906 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
907 }
908 } else {
909 if (pd->read_speed != pd->write_speed) {
910 pd->read_speed = pd->write_speed;
911 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
912 }
913 }
914
915 atomic_inc(&pd->cdrw.pending_bios);
916 generic_make_request(bio);
917 }
918 }
919
920 /*
921 * Special care is needed if the underlying block device has a small
922 * max_phys_segments value.
923 */
924 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
925 {
926 if ((pd->settings.size << 9) / CD_FRAMESIZE
927 <= queue_max_segments(q)) {
928 /*
929 * The cdrom device can handle one segment/frame
930 */
931 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
932 return 0;
933 } else if ((pd->settings.size << 9) / PAGE_SIZE
934 <= queue_max_segments(q)) {
935 /*
936 * We can handle this case at the expense of some extra memory
937 * copies during write operations
938 */
939 set_bit(PACKET_MERGE_SEGS, &pd->flags);
940 return 0;
941 } else {
942 pkt_err(pd, "cdrom max_phys_segments too small\n");
943 return -EIO;
944 }
945 }
946
947 /*
948 * Copy all data for this packet to pkt->pages[], so that
949 * a) The number of required segments for the write bio is minimized, which
950 * is necessary for some scsi controllers.
951 * b) The data can be used as cache to avoid read requests if we receive a
952 * new write request for the same zone.
953 */
954 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
955 {
956 int f, p, offs;
957
958 /* Copy all data to pkt->pages[] */
959 p = 0;
960 offs = 0;
961 for (f = 0; f < pkt->frames; f++) {
962 if (bvec[f].bv_page != pkt->pages[p]) {
963 void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset;
964 void *vto = page_address(pkt->pages[p]) + offs;
965 memcpy(vto, vfrom, CD_FRAMESIZE);
966 kunmap_atomic(vfrom);
967 bvec[f].bv_page = pkt->pages[p];
968 bvec[f].bv_offset = offs;
969 } else {
970 BUG_ON(bvec[f].bv_offset != offs);
971 }
972 offs += CD_FRAMESIZE;
973 if (offs >= PAGE_SIZE) {
974 offs = 0;
975 p++;
976 }
977 }
978 }
979
980 static void pkt_end_io_read(struct bio *bio, int err)
981 {
982 struct packet_data *pkt = bio->bi_private;
983 struct pktcdvd_device *pd = pkt->pd;
984 BUG_ON(!pd);
985
986 pkt_dbg(2, pd, "bio=%p sec0=%llx sec=%llx err=%d\n",
987 bio, (unsigned long long)pkt->sector,
988 (unsigned long long)bio->bi_iter.bi_sector, err);
989
990 if (err)
991 atomic_inc(&pkt->io_errors);
992 if (atomic_dec_and_test(&pkt->io_wait)) {
993 atomic_inc(&pkt->run_sm);
994 wake_up(&pd->wqueue);
995 }
996 pkt_bio_finished(pd);
997 }
998
999 static void pkt_end_io_packet_write(struct bio *bio, int err)
1000 {
1001 struct packet_data *pkt = bio->bi_private;
1002 struct pktcdvd_device *pd = pkt->pd;
1003 BUG_ON(!pd);
1004
1005 pkt_dbg(2, pd, "id=%d, err=%d\n", pkt->id, err);
1006
1007 pd->stats.pkt_ended++;
1008
1009 pkt_bio_finished(pd);
1010 atomic_dec(&pkt->io_wait);
1011 atomic_inc(&pkt->run_sm);
1012 wake_up(&pd->wqueue);
1013 }
1014
1015 /*
1016 * Schedule reads for the holes in a packet
1017 */
1018 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1019 {
1020 int frames_read = 0;
1021 struct bio *bio;
1022 int f;
1023 char written[PACKET_MAX_SIZE];
1024
1025 BUG_ON(bio_list_empty(&pkt->orig_bios));
1026
1027 atomic_set(&pkt->io_wait, 0);
1028 atomic_set(&pkt->io_errors, 0);
1029
1030 /*
1031 * Figure out which frames we need to read before we can write.
1032 */
1033 memset(written, 0, sizeof(written));
1034 spin_lock(&pkt->lock);
1035 bio_list_for_each(bio, &pkt->orig_bios) {
1036 int first_frame = (bio->bi_iter.bi_sector - pkt->sector) /
1037 (CD_FRAMESIZE >> 9);
1038 int num_frames = bio->bi_iter.bi_size / CD_FRAMESIZE;
1039 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1040 BUG_ON(first_frame < 0);
1041 BUG_ON(first_frame + num_frames > pkt->frames);
1042 for (f = first_frame; f < first_frame + num_frames; f++)
1043 written[f] = 1;
1044 }
1045 spin_unlock(&pkt->lock);
1046
1047 if (pkt->cache_valid) {
1048 pkt_dbg(2, pd, "zone %llx cached\n",
1049 (unsigned long long)pkt->sector);
1050 goto out_account;
1051 }
1052
1053 /*
1054 * Schedule reads for missing parts of the packet.
1055 */
1056 for (f = 0; f < pkt->frames; f++) {
1057 int p, offset;
1058
1059 if (written[f])
1060 continue;
1061
1062 bio = pkt->r_bios[f];
1063 bio_reset(bio);
1064 bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1065 bio->bi_bdev = pd->bdev;
1066 bio->bi_end_io = pkt_end_io_read;
1067 bio->bi_private = pkt;
1068
1069 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1070 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1071 pkt_dbg(2, pd, "Adding frame %d, page:%p offs:%d\n",
1072 f, pkt->pages[p], offset);
1073 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1074 BUG();
1075
1076 atomic_inc(&pkt->io_wait);
1077 bio->bi_rw = READ;
1078 pkt_queue_bio(pd, bio);
1079 frames_read++;
1080 }
1081
1082 out_account:
1083 pkt_dbg(2, pd, "need %d frames for zone %llx\n",
1084 frames_read, (unsigned long long)pkt->sector);
1085 pd->stats.pkt_started++;
1086 pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1087 }
1088
1089 /*
1090 * Find a packet matching zone, or the least recently used packet if
1091 * there is no match.
1092 */
1093 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1094 {
1095 struct packet_data *pkt;
1096
1097 list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1098 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1099 list_del_init(&pkt->list);
1100 if (pkt->sector != zone)
1101 pkt->cache_valid = 0;
1102 return pkt;
1103 }
1104 }
1105 BUG();
1106 return NULL;
1107 }
1108
1109 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1110 {
1111 if (pkt->cache_valid) {
1112 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1113 } else {
1114 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1115 }
1116 }
1117
1118 /*
1119 * recover a failed write, query for relocation if possible
1120 *
1121 * returns 1 if recovery is possible, or 0 if not
1122 *
1123 */
1124 static int pkt_start_recovery(struct packet_data *pkt)
1125 {
1126 /*
1127 * FIXME. We need help from the file system to implement
1128 * recovery handling.
1129 */
1130 return 0;
1131 #if 0
1132 struct request *rq = pkt->rq;
1133 struct pktcdvd_device *pd = rq->rq_disk->private_data;
1134 struct block_device *pkt_bdev;
1135 struct super_block *sb = NULL;
1136 unsigned long old_block, new_block;
1137 sector_t new_sector;
1138
1139 pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1140 if (pkt_bdev) {
1141 sb = get_super(pkt_bdev);
1142 bdput(pkt_bdev);
1143 }
1144
1145 if (!sb)
1146 return 0;
1147
1148 if (!sb->s_op->relocate_blocks)
1149 goto out;
1150
1151 old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1152 if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1153 goto out;
1154
1155 new_sector = new_block * (CD_FRAMESIZE >> 9);
1156 pkt->sector = new_sector;
1157
1158 bio_reset(pkt->bio);
1159 pkt->bio->bi_bdev = pd->bdev;
1160 pkt->bio->bi_rw = REQ_WRITE;
1161 pkt->bio->bi_iter.bi_sector = new_sector;
1162 pkt->bio->bi_iter.bi_size = pkt->frames * CD_FRAMESIZE;
1163 pkt->bio->bi_vcnt = pkt->frames;
1164
1165 pkt->bio->bi_end_io = pkt_end_io_packet_write;
1166 pkt->bio->bi_private = pkt;
1167
1168 drop_super(sb);
1169 return 1;
1170
1171 out:
1172 drop_super(sb);
1173 return 0;
1174 #endif
1175 }
1176
1177 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1178 {
1179 #if PACKET_DEBUG > 1
1180 static const char *state_name[] = {
1181 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1182 };
1183 enum packet_data_state old_state = pkt->state;
1184 pkt_dbg(2, pd, "pkt %2d : s=%6llx %s -> %s\n",
1185 pkt->id, (unsigned long long)pkt->sector,
1186 state_name[old_state], state_name[state]);
1187 #endif
1188 pkt->state = state;
1189 }
1190
1191 /*
1192 * Scan the work queue to see if we can start a new packet.
1193 * returns non-zero if any work was done.
1194 */
1195 static int pkt_handle_queue(struct pktcdvd_device *pd)
1196 {
1197 struct packet_data *pkt, *p;
1198 struct bio *bio = NULL;
1199 sector_t zone = 0; /* Suppress gcc warning */
1200 struct pkt_rb_node *node, *first_node;
1201 struct rb_node *n;
1202 int wakeup;
1203
1204 atomic_set(&pd->scan_queue, 0);
1205
1206 if (list_empty(&pd->cdrw.pkt_free_list)) {
1207 pkt_dbg(2, pd, "no pkt\n");
1208 return 0;
1209 }
1210
1211 /*
1212 * Try to find a zone we are not already working on.
1213 */
1214 spin_lock(&pd->lock);
1215 first_node = pkt_rbtree_find(pd, pd->current_sector);
1216 if (!first_node) {
1217 n = rb_first(&pd->bio_queue);
1218 if (n)
1219 first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1220 }
1221 node = first_node;
1222 while (node) {
1223 bio = node->bio;
1224 zone = get_zone(bio->bi_iter.bi_sector, pd);
1225 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1226 if (p->sector == zone) {
1227 bio = NULL;
1228 goto try_next_bio;
1229 }
1230 }
1231 break;
1232 try_next_bio:
1233 node = pkt_rbtree_next(node);
1234 if (!node) {
1235 n = rb_first(&pd->bio_queue);
1236 if (n)
1237 node = rb_entry(n, struct pkt_rb_node, rb_node);
1238 }
1239 if (node == first_node)
1240 node = NULL;
1241 }
1242 spin_unlock(&pd->lock);
1243 if (!bio) {
1244 pkt_dbg(2, pd, "no bio\n");
1245 return 0;
1246 }
1247
1248 pkt = pkt_get_packet_data(pd, zone);
1249
1250 pd->current_sector = zone + pd->settings.size;
1251 pkt->sector = zone;
1252 BUG_ON(pkt->frames != pd->settings.size >> 2);
1253 pkt->write_size = 0;
1254
1255 /*
1256 * Scan work queue for bios in the same zone and link them
1257 * to this packet.
1258 */
1259 spin_lock(&pd->lock);
1260 pkt_dbg(2, pd, "looking for zone %llx\n", (unsigned long long)zone);
1261 while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1262 bio = node->bio;
1263 pkt_dbg(2, pd, "found zone=%llx\n", (unsigned long long)
1264 get_zone(bio->bi_iter.bi_sector, pd));
1265 if (get_zone(bio->bi_iter.bi_sector, pd) != zone)
1266 break;
1267 pkt_rbtree_erase(pd, node);
1268 spin_lock(&pkt->lock);
1269 bio_list_add(&pkt->orig_bios, bio);
1270 pkt->write_size += bio->bi_iter.bi_size / CD_FRAMESIZE;
1271 spin_unlock(&pkt->lock);
1272 }
1273 /* check write congestion marks, and if bio_queue_size is
1274 below, wake up any waiters */
1275 wakeup = (pd->write_congestion_on > 0
1276 && pd->bio_queue_size <= pd->write_congestion_off);
1277 spin_unlock(&pd->lock);
1278 if (wakeup) {
1279 clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1280 BLK_RW_ASYNC);
1281 }
1282
1283 pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1284 pkt_set_state(pkt, PACKET_WAITING_STATE);
1285 atomic_set(&pkt->run_sm, 1);
1286
1287 spin_lock(&pd->cdrw.active_list_lock);
1288 list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1289 spin_unlock(&pd->cdrw.active_list_lock);
1290
1291 return 1;
1292 }
1293
1294 /*
1295 * Assemble a bio to write one packet and queue the bio for processing
1296 * by the underlying block device.
1297 */
1298 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1299 {
1300 int f;
1301 struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1302
1303 bio_reset(pkt->w_bio);
1304 pkt->w_bio->bi_iter.bi_sector = pkt->sector;
1305 pkt->w_bio->bi_bdev = pd->bdev;
1306 pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1307 pkt->w_bio->bi_private = pkt;
1308
1309 /* XXX: locking? */
1310 for (f = 0; f < pkt->frames; f++) {
1311 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1312 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1313 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1314 BUG();
1315 }
1316 pkt_dbg(2, pd, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
1317
1318 /*
1319 * Fill-in bvec with data from orig_bios.
1320 */
1321 spin_lock(&pkt->lock);
1322 bio_copy_data(pkt->w_bio, pkt->orig_bios.head);
1323
1324 pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1325 spin_unlock(&pkt->lock);
1326
1327 pkt_dbg(2, pd, "Writing %d frames for zone %llx\n",
1328 pkt->write_size, (unsigned long long)pkt->sector);
1329
1330 if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1331 pkt_make_local_copy(pkt, bvec);
1332 pkt->cache_valid = 1;
1333 } else {
1334 pkt->cache_valid = 0;
1335 }
1336
1337 /* Start the write request */
1338 atomic_set(&pkt->io_wait, 1);
1339 pkt->w_bio->bi_rw = WRITE;
1340 pkt_queue_bio(pd, pkt->w_bio);
1341 }
1342
1343 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1344 {
1345 struct bio *bio;
1346
1347 if (!uptodate)
1348 pkt->cache_valid = 0;
1349
1350 /* Finish all bios corresponding to this packet */
1351 while ((bio = bio_list_pop(&pkt->orig_bios)))
1352 bio_endio(bio, uptodate ? 0 : -EIO);
1353 }
1354
1355 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1356 {
1357 int uptodate;
1358
1359 pkt_dbg(2, pd, "pkt %d\n", pkt->id);
1360
1361 for (;;) {
1362 switch (pkt->state) {
1363 case PACKET_WAITING_STATE:
1364 if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1365 return;
1366
1367 pkt->sleep_time = 0;
1368 pkt_gather_data(pd, pkt);
1369 pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1370 break;
1371
1372 case PACKET_READ_WAIT_STATE:
1373 if (atomic_read(&pkt->io_wait) > 0)
1374 return;
1375
1376 if (atomic_read(&pkt->io_errors) > 0) {
1377 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1378 } else {
1379 pkt_start_write(pd, pkt);
1380 }
1381 break;
1382
1383 case PACKET_WRITE_WAIT_STATE:
1384 if (atomic_read(&pkt->io_wait) > 0)
1385 return;
1386
1387 if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1388 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1389 } else {
1390 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1391 }
1392 break;
1393
1394 case PACKET_RECOVERY_STATE:
1395 if (pkt_start_recovery(pkt)) {
1396 pkt_start_write(pd, pkt);
1397 } else {
1398 pkt_dbg(2, pd, "No recovery possible\n");
1399 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1400 }
1401 break;
1402
1403 case PACKET_FINISHED_STATE:
1404 uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1405 pkt_finish_packet(pkt, uptodate);
1406 return;
1407
1408 default:
1409 BUG();
1410 break;
1411 }
1412 }
1413 }
1414
1415 static void pkt_handle_packets(struct pktcdvd_device *pd)
1416 {
1417 struct packet_data *pkt, *next;
1418
1419 /*
1420 * Run state machine for active packets
1421 */
1422 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1423 if (atomic_read(&pkt->run_sm) > 0) {
1424 atomic_set(&pkt->run_sm, 0);
1425 pkt_run_state_machine(pd, pkt);
1426 }
1427 }
1428
1429 /*
1430 * Move no longer active packets to the free list
1431 */
1432 spin_lock(&pd->cdrw.active_list_lock);
1433 list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1434 if (pkt->state == PACKET_FINISHED_STATE) {
1435 list_del(&pkt->list);
1436 pkt_put_packet_data(pd, pkt);
1437 pkt_set_state(pkt, PACKET_IDLE_STATE);
1438 atomic_set(&pd->scan_queue, 1);
1439 }
1440 }
1441 spin_unlock(&pd->cdrw.active_list_lock);
1442 }
1443
1444 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1445 {
1446 struct packet_data *pkt;
1447 int i;
1448
1449 for (i = 0; i < PACKET_NUM_STATES; i++)
1450 states[i] = 0;
1451
1452 spin_lock(&pd->cdrw.active_list_lock);
1453 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1454 states[pkt->state]++;
1455 }
1456 spin_unlock(&pd->cdrw.active_list_lock);
1457 }
1458
1459 /*
1460 * kcdrwd is woken up when writes have been queued for one of our
1461 * registered devices
1462 */
1463 static int kcdrwd(void *foobar)
1464 {
1465 struct pktcdvd_device *pd = foobar;
1466 struct packet_data *pkt;
1467 long min_sleep_time, residue;
1468
1469 set_user_nice(current, MIN_NICE);
1470 set_freezable();
1471
1472 for (;;) {
1473 DECLARE_WAITQUEUE(wait, current);
1474
1475 /*
1476 * Wait until there is something to do
1477 */
1478 add_wait_queue(&pd->wqueue, &wait);
1479 for (;;) {
1480 set_current_state(TASK_INTERRUPTIBLE);
1481
1482 /* Check if we need to run pkt_handle_queue */
1483 if (atomic_read(&pd->scan_queue) > 0)
1484 goto work_to_do;
1485
1486 /* Check if we need to run the state machine for some packet */
1487 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1488 if (atomic_read(&pkt->run_sm) > 0)
1489 goto work_to_do;
1490 }
1491
1492 /* Check if we need to process the iosched queues */
1493 if (atomic_read(&pd->iosched.attention) != 0)
1494 goto work_to_do;
1495
1496 /* Otherwise, go to sleep */
1497 if (PACKET_DEBUG > 1) {
1498 int states[PACKET_NUM_STATES];
1499 pkt_count_states(pd, states);
1500 pkt_dbg(2, pd, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1501 states[0], states[1], states[2],
1502 states[3], states[4], states[5]);
1503 }
1504
1505 min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1506 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1507 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1508 min_sleep_time = pkt->sleep_time;
1509 }
1510
1511 pkt_dbg(2, pd, "sleeping\n");
1512 residue = schedule_timeout(min_sleep_time);
1513 pkt_dbg(2, pd, "wake up\n");
1514
1515 /* make swsusp happy with our thread */
1516 try_to_freeze();
1517
1518 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1519 if (!pkt->sleep_time)
1520 continue;
1521 pkt->sleep_time -= min_sleep_time - residue;
1522 if (pkt->sleep_time <= 0) {
1523 pkt->sleep_time = 0;
1524 atomic_inc(&pkt->run_sm);
1525 }
1526 }
1527
1528 if (kthread_should_stop())
1529 break;
1530 }
1531 work_to_do:
1532 set_current_state(TASK_RUNNING);
1533 remove_wait_queue(&pd->wqueue, &wait);
1534
1535 if (kthread_should_stop())
1536 break;
1537
1538 /*
1539 * if pkt_handle_queue returns true, we can queue
1540 * another request.
1541 */
1542 while (pkt_handle_queue(pd))
1543 ;
1544
1545 /*
1546 * Handle packet state machine
1547 */
1548 pkt_handle_packets(pd);
1549
1550 /*
1551 * Handle iosched queues
1552 */
1553 pkt_iosched_process_queue(pd);
1554 }
1555
1556 return 0;
1557 }
1558
1559 static void pkt_print_settings(struct pktcdvd_device *pd)
1560 {
1561 pkt_info(pd, "%s packets, %u blocks, Mode-%c disc\n",
1562 pd->settings.fp ? "Fixed" : "Variable",
1563 pd->settings.size >> 2,
1564 pd->settings.block_mode == 8 ? '1' : '2');
1565 }
1566
1567 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1568 {
1569 memset(cgc->cmd, 0, sizeof(cgc->cmd));
1570
1571 cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1572 cgc->cmd[2] = page_code | (page_control << 6);
1573 cgc->cmd[7] = cgc->buflen >> 8;
1574 cgc->cmd[8] = cgc->buflen & 0xff;
1575 cgc->data_direction = CGC_DATA_READ;
1576 return pkt_generic_packet(pd, cgc);
1577 }
1578
1579 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1580 {
1581 memset(cgc->cmd, 0, sizeof(cgc->cmd));
1582 memset(cgc->buffer, 0, 2);
1583 cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1584 cgc->cmd[1] = 0x10; /* PF */
1585 cgc->cmd[7] = cgc->buflen >> 8;
1586 cgc->cmd[8] = cgc->buflen & 0xff;
1587 cgc->data_direction = CGC_DATA_WRITE;
1588 return pkt_generic_packet(pd, cgc);
1589 }
1590
1591 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1592 {
1593 struct packet_command cgc;
1594 int ret;
1595
1596 /* set up command and get the disc info */
1597 init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1598 cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1599 cgc.cmd[8] = cgc.buflen = 2;
1600 cgc.quiet = 1;
1601
1602 if ((ret = pkt_generic_packet(pd, &cgc)))
1603 return ret;
1604
1605 /* not all drives have the same disc_info length, so requeue
1606 * packet with the length the drive tells us it can supply
1607 */
1608 cgc.buflen = be16_to_cpu(di->disc_information_length) +
1609 sizeof(di->disc_information_length);
1610
1611 if (cgc.buflen > sizeof(disc_information))
1612 cgc.buflen = sizeof(disc_information);
1613
1614 cgc.cmd[8] = cgc.buflen;
1615 return pkt_generic_packet(pd, &cgc);
1616 }
1617
1618 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1619 {
1620 struct packet_command cgc;
1621 int ret;
1622
1623 init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1624 cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1625 cgc.cmd[1] = type & 3;
1626 cgc.cmd[4] = (track & 0xff00) >> 8;
1627 cgc.cmd[5] = track & 0xff;
1628 cgc.cmd[8] = 8;
1629 cgc.quiet = 1;
1630
1631 if ((ret = pkt_generic_packet(pd, &cgc)))
1632 return ret;
1633
1634 cgc.buflen = be16_to_cpu(ti->track_information_length) +
1635 sizeof(ti->track_information_length);
1636
1637 if (cgc.buflen > sizeof(track_information))
1638 cgc.buflen = sizeof(track_information);
1639
1640 cgc.cmd[8] = cgc.buflen;
1641 return pkt_generic_packet(pd, &cgc);
1642 }
1643
1644 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1645 long *last_written)
1646 {
1647 disc_information di;
1648 track_information ti;
1649 __u32 last_track;
1650 int ret = -1;
1651
1652 if ((ret = pkt_get_disc_info(pd, &di)))
1653 return ret;
1654
1655 last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1656 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1657 return ret;
1658
1659 /* if this track is blank, try the previous. */
1660 if (ti.blank) {
1661 last_track--;
1662 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1663 return ret;
1664 }
1665
1666 /* if last recorded field is valid, return it. */
1667 if (ti.lra_v) {
1668 *last_written = be32_to_cpu(ti.last_rec_address);
1669 } else {
1670 /* make it up instead */
1671 *last_written = be32_to_cpu(ti.track_start) +
1672 be32_to_cpu(ti.track_size);
1673 if (ti.free_blocks)
1674 *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1675 }
1676 return 0;
1677 }
1678
1679 /*
1680 * write mode select package based on pd->settings
1681 */
1682 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1683 {
1684 struct packet_command cgc;
1685 struct request_sense sense;
1686 write_param_page *wp;
1687 char buffer[128];
1688 int ret, size;
1689
1690 /* doesn't apply to DVD+RW or DVD-RAM */
1691 if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1692 return 0;
1693
1694 memset(buffer, 0, sizeof(buffer));
1695 init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1696 cgc.sense = &sense;
1697 if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1698 pkt_dump_sense(pd, &cgc);
1699 return ret;
1700 }
1701
1702 size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1703 pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1704 if (size > sizeof(buffer))
1705 size = sizeof(buffer);
1706
1707 /*
1708 * now get it all
1709 */
1710 init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1711 cgc.sense = &sense;
1712 if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1713 pkt_dump_sense(pd, &cgc);
1714 return ret;
1715 }
1716
1717 /*
1718 * write page is offset header + block descriptor length
1719 */
1720 wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1721
1722 wp->fp = pd->settings.fp;
1723 wp->track_mode = pd->settings.track_mode;
1724 wp->write_type = pd->settings.write_type;
1725 wp->data_block_type = pd->settings.block_mode;
1726
1727 wp->multi_session = 0;
1728
1729 #ifdef PACKET_USE_LS
1730 wp->link_size = 7;
1731 wp->ls_v = 1;
1732 #endif
1733
1734 if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1735 wp->session_format = 0;
1736 wp->subhdr2 = 0x20;
1737 } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1738 wp->session_format = 0x20;
1739 wp->subhdr2 = 8;
1740 #if 0
1741 wp->mcn[0] = 0x80;
1742 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1743 #endif
1744 } else {
1745 /*
1746 * paranoia
1747 */
1748 pkt_err(pd, "write mode wrong %d\n", wp->data_block_type);
1749 return 1;
1750 }
1751 wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1752
1753 cgc.buflen = cgc.cmd[8] = size;
1754 if ((ret = pkt_mode_select(pd, &cgc))) {
1755 pkt_dump_sense(pd, &cgc);
1756 return ret;
1757 }
1758
1759 pkt_print_settings(pd);
1760 return 0;
1761 }
1762
1763 /*
1764 * 1 -- we can write to this track, 0 -- we can't
1765 */
1766 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1767 {
1768 switch (pd->mmc3_profile) {
1769 case 0x1a: /* DVD+RW */
1770 case 0x12: /* DVD-RAM */
1771 /* The track is always writable on DVD+RW/DVD-RAM */
1772 return 1;
1773 default:
1774 break;
1775 }
1776
1777 if (!ti->packet || !ti->fp)
1778 return 0;
1779
1780 /*
1781 * "good" settings as per Mt Fuji.
1782 */
1783 if (ti->rt == 0 && ti->blank == 0)
1784 return 1;
1785
1786 if (ti->rt == 0 && ti->blank == 1)
1787 return 1;
1788
1789 if (ti->rt == 1 && ti->blank == 0)
1790 return 1;
1791
1792 pkt_err(pd, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1793 return 0;
1794 }
1795
1796 /*
1797 * 1 -- we can write to this disc, 0 -- we can't
1798 */
1799 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1800 {
1801 switch (pd->mmc3_profile) {
1802 case 0x0a: /* CD-RW */
1803 case 0xffff: /* MMC3 not supported */
1804 break;
1805 case 0x1a: /* DVD+RW */
1806 case 0x13: /* DVD-RW */
1807 case 0x12: /* DVD-RAM */
1808 return 1;
1809 default:
1810 pkt_dbg(2, pd, "Wrong disc profile (%x)\n",
1811 pd->mmc3_profile);
1812 return 0;
1813 }
1814
1815 /*
1816 * for disc type 0xff we should probably reserve a new track.
1817 * but i'm not sure, should we leave this to user apps? probably.
1818 */
1819 if (di->disc_type == 0xff) {
1820 pkt_notice(pd, "unknown disc - no track?\n");
1821 return 0;
1822 }
1823
1824 if (di->disc_type != 0x20 && di->disc_type != 0) {
1825 pkt_err(pd, "wrong disc type (%x)\n", di->disc_type);
1826 return 0;
1827 }
1828
1829 if (di->erasable == 0) {
1830 pkt_notice(pd, "disc not erasable\n");
1831 return 0;
1832 }
1833
1834 if (di->border_status == PACKET_SESSION_RESERVED) {
1835 pkt_err(pd, "can't write to last track (reserved)\n");
1836 return 0;
1837 }
1838
1839 return 1;
1840 }
1841
1842 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1843 {
1844 struct packet_command cgc;
1845 unsigned char buf[12];
1846 disc_information di;
1847 track_information ti;
1848 int ret, track;
1849
1850 init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1851 cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1852 cgc.cmd[8] = 8;
1853 ret = pkt_generic_packet(pd, &cgc);
1854 pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1855
1856 memset(&di, 0, sizeof(disc_information));
1857 memset(&ti, 0, sizeof(track_information));
1858
1859 if ((ret = pkt_get_disc_info(pd, &di))) {
1860 pkt_err(pd, "failed get_disc\n");
1861 return ret;
1862 }
1863
1864 if (!pkt_writable_disc(pd, &di))
1865 return -EROFS;
1866
1867 pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1868
1869 track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1870 if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1871 pkt_err(pd, "failed get_track\n");
1872 return ret;
1873 }
1874
1875 if (!pkt_writable_track(pd, &ti)) {
1876 pkt_err(pd, "can't write to this track\n");
1877 return -EROFS;
1878 }
1879
1880 /*
1881 * we keep packet size in 512 byte units, makes it easier to
1882 * deal with request calculations.
1883 */
1884 pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1885 if (pd->settings.size == 0) {
1886 pkt_notice(pd, "detected zero packet size!\n");
1887 return -ENXIO;
1888 }
1889 if (pd->settings.size > PACKET_MAX_SECTORS) {
1890 pkt_err(pd, "packet size is too big\n");
1891 return -EROFS;
1892 }
1893 pd->settings.fp = ti.fp;
1894 pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1895
1896 if (ti.nwa_v) {
1897 pd->nwa = be32_to_cpu(ti.next_writable);
1898 set_bit(PACKET_NWA_VALID, &pd->flags);
1899 }
1900
1901 /*
1902 * in theory we could use lra on -RW media as well and just zero
1903 * blocks that haven't been written yet, but in practice that
1904 * is just a no-go. we'll use that for -R, naturally.
1905 */
1906 if (ti.lra_v) {
1907 pd->lra = be32_to_cpu(ti.last_rec_address);
1908 set_bit(PACKET_LRA_VALID, &pd->flags);
1909 } else {
1910 pd->lra = 0xffffffff;
1911 set_bit(PACKET_LRA_VALID, &pd->flags);
1912 }
1913
1914 /*
1915 * fine for now
1916 */
1917 pd->settings.link_loss = 7;
1918 pd->settings.write_type = 0; /* packet */
1919 pd->settings.track_mode = ti.track_mode;
1920
1921 /*
1922 * mode1 or mode2 disc
1923 */
1924 switch (ti.data_mode) {
1925 case PACKET_MODE1:
1926 pd->settings.block_mode = PACKET_BLOCK_MODE1;
1927 break;
1928 case PACKET_MODE2:
1929 pd->settings.block_mode = PACKET_BLOCK_MODE2;
1930 break;
1931 default:
1932 pkt_err(pd, "unknown data mode\n");
1933 return -EROFS;
1934 }
1935 return 0;
1936 }
1937
1938 /*
1939 * enable/disable write caching on drive
1940 */
1941 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
1942 int set)
1943 {
1944 struct packet_command cgc;
1945 struct request_sense sense;
1946 unsigned char buf[64];
1947 int ret;
1948
1949 init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1950 cgc.sense = &sense;
1951 cgc.buflen = pd->mode_offset + 12;
1952
1953 /*
1954 * caching mode page might not be there, so quiet this command
1955 */
1956 cgc.quiet = 1;
1957
1958 if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1959 return ret;
1960
1961 buf[pd->mode_offset + 10] |= (!!set << 2);
1962
1963 cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1964 ret = pkt_mode_select(pd, &cgc);
1965 if (ret) {
1966 pkt_err(pd, "write caching control failed\n");
1967 pkt_dump_sense(pd, &cgc);
1968 } else if (!ret && set)
1969 pkt_notice(pd, "enabled write caching\n");
1970 return ret;
1971 }
1972
1973 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1974 {
1975 struct packet_command cgc;
1976
1977 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1978 cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1979 cgc.cmd[4] = lockflag ? 1 : 0;
1980 return pkt_generic_packet(pd, &cgc);
1981 }
1982
1983 /*
1984 * Returns drive maximum write speed
1985 */
1986 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1987 unsigned *write_speed)
1988 {
1989 struct packet_command cgc;
1990 struct request_sense sense;
1991 unsigned char buf[256+18];
1992 unsigned char *cap_buf;
1993 int ret, offset;
1994
1995 cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1996 init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1997 cgc.sense = &sense;
1998
1999 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2000 if (ret) {
2001 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2002 sizeof(struct mode_page_header);
2003 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2004 if (ret) {
2005 pkt_dump_sense(pd, &cgc);
2006 return ret;
2007 }
2008 }
2009
2010 offset = 20; /* Obsoleted field, used by older drives */
2011 if (cap_buf[1] >= 28)
2012 offset = 28; /* Current write speed selected */
2013 if (cap_buf[1] >= 30) {
2014 /* If the drive reports at least one "Logical Unit Write
2015 * Speed Performance Descriptor Block", use the information
2016 * in the first block. (contains the highest speed)
2017 */
2018 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2019 if (num_spdb > 0)
2020 offset = 34;
2021 }
2022
2023 *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2024 return 0;
2025 }
2026
2027 /* These tables from cdrecord - I don't have orange book */
2028 /* standard speed CD-RW (1-4x) */
2029 static char clv_to_speed[16] = {
2030 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
2031 0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2032 };
2033 /* high speed CD-RW (-10x) */
2034 static char hs_clv_to_speed[16] = {
2035 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
2036 0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2037 };
2038 /* ultra high speed CD-RW */
2039 static char us_clv_to_speed[16] = {
2040 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
2041 0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2042 };
2043
2044 /*
2045 * reads the maximum media speed from ATIP
2046 */
2047 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2048 unsigned *speed)
2049 {
2050 struct packet_command cgc;
2051 struct request_sense sense;
2052 unsigned char buf[64];
2053 unsigned int size, st, sp;
2054 int ret;
2055
2056 init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2057 cgc.sense = &sense;
2058 cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2059 cgc.cmd[1] = 2;
2060 cgc.cmd[2] = 4; /* READ ATIP */
2061 cgc.cmd[8] = 2;
2062 ret = pkt_generic_packet(pd, &cgc);
2063 if (ret) {
2064 pkt_dump_sense(pd, &cgc);
2065 return ret;
2066 }
2067 size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2068 if (size > sizeof(buf))
2069 size = sizeof(buf);
2070
2071 init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2072 cgc.sense = &sense;
2073 cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2074 cgc.cmd[1] = 2;
2075 cgc.cmd[2] = 4;
2076 cgc.cmd[8] = size;
2077 ret = pkt_generic_packet(pd, &cgc);
2078 if (ret) {
2079 pkt_dump_sense(pd, &cgc);
2080 return ret;
2081 }
2082
2083 if (!(buf[6] & 0x40)) {
2084 pkt_notice(pd, "disc type is not CD-RW\n");
2085 return 1;
2086 }
2087 if (!(buf[6] & 0x4)) {
2088 pkt_notice(pd, "A1 values on media are not valid, maybe not CDRW?\n");
2089 return 1;
2090 }
2091
2092 st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2093
2094 sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2095
2096 /* Info from cdrecord */
2097 switch (st) {
2098 case 0: /* standard speed */
2099 *speed = clv_to_speed[sp];
2100 break;
2101 case 1: /* high speed */
2102 *speed = hs_clv_to_speed[sp];
2103 break;
2104 case 2: /* ultra high speed */
2105 *speed = us_clv_to_speed[sp];
2106 break;
2107 default:
2108 pkt_notice(pd, "unknown disc sub-type %d\n", st);
2109 return 1;
2110 }
2111 if (*speed) {
2112 pkt_info(pd, "maximum media speed: %d\n", *speed);
2113 return 0;
2114 } else {
2115 pkt_notice(pd, "unknown speed %d for sub-type %d\n", sp, st);
2116 return 1;
2117 }
2118 }
2119
2120 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2121 {
2122 struct packet_command cgc;
2123 struct request_sense sense;
2124 int ret;
2125
2126 pkt_dbg(2, pd, "Performing OPC\n");
2127
2128 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2129 cgc.sense = &sense;
2130 cgc.timeout = 60*HZ;
2131 cgc.cmd[0] = GPCMD_SEND_OPC;
2132 cgc.cmd[1] = 1;
2133 if ((ret = pkt_generic_packet(pd, &cgc)))
2134 pkt_dump_sense(pd, &cgc);
2135 return ret;
2136 }
2137
2138 static int pkt_open_write(struct pktcdvd_device *pd)
2139 {
2140 int ret;
2141 unsigned int write_speed, media_write_speed, read_speed;
2142
2143 if ((ret = pkt_probe_settings(pd))) {
2144 pkt_dbg(2, pd, "failed probe\n");
2145 return ret;
2146 }
2147
2148 if ((ret = pkt_set_write_settings(pd))) {
2149 pkt_dbg(1, pd, "failed saving write settings\n");
2150 return -EIO;
2151 }
2152
2153 pkt_write_caching(pd, USE_WCACHING);
2154
2155 if ((ret = pkt_get_max_speed(pd, &write_speed)))
2156 write_speed = 16 * 177;
2157 switch (pd->mmc3_profile) {
2158 case 0x13: /* DVD-RW */
2159 case 0x1a: /* DVD+RW */
2160 case 0x12: /* DVD-RAM */
2161 pkt_dbg(1, pd, "write speed %ukB/s\n", write_speed);
2162 break;
2163 default:
2164 if ((ret = pkt_media_speed(pd, &media_write_speed)))
2165 media_write_speed = 16;
2166 write_speed = min(write_speed, media_write_speed * 177);
2167 pkt_dbg(1, pd, "write speed %ux\n", write_speed / 176);
2168 break;
2169 }
2170 read_speed = write_speed;
2171
2172 if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2173 pkt_dbg(1, pd, "couldn't set write speed\n");
2174 return -EIO;
2175 }
2176 pd->write_speed = write_speed;
2177 pd->read_speed = read_speed;
2178
2179 if ((ret = pkt_perform_opc(pd))) {
2180 pkt_dbg(1, pd, "Optimum Power Calibration failed\n");
2181 }
2182
2183 return 0;
2184 }
2185
2186 /*
2187 * called at open time.
2188 */
2189 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2190 {
2191 int ret;
2192 long lba;
2193 struct request_queue *q;
2194
2195 /*
2196 * We need to re-open the cdrom device without O_NONBLOCK to be able
2197 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2198 * so bdget() can't fail.
2199 */
2200 bdget(pd->bdev->bd_dev);
2201 if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2202 goto out;
2203
2204 if ((ret = pkt_get_last_written(pd, &lba))) {
2205 pkt_err(pd, "pkt_get_last_written failed\n");
2206 goto out_putdev;
2207 }
2208
2209 set_capacity(pd->disk, lba << 2);
2210 set_capacity(pd->bdev->bd_disk, lba << 2);
2211 bd_set_size(pd->bdev, (loff_t)lba << 11);
2212
2213 q = bdev_get_queue(pd->bdev);
2214 if (write) {
2215 if ((ret = pkt_open_write(pd)))
2216 goto out_putdev;
2217 /*
2218 * Some CDRW drives can not handle writes larger than one packet,
2219 * even if the size is a multiple of the packet size.
2220 */
2221 spin_lock_irq(q->queue_lock);
2222 blk_queue_max_hw_sectors(q, pd->settings.size);
2223 spin_unlock_irq(q->queue_lock);
2224 set_bit(PACKET_WRITABLE, &pd->flags);
2225 } else {
2226 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2227 clear_bit(PACKET_WRITABLE, &pd->flags);
2228 }
2229
2230 if ((ret = pkt_set_segment_merging(pd, q)))
2231 goto out_putdev;
2232
2233 if (write) {
2234 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2235 pkt_err(pd, "not enough memory for buffers\n");
2236 ret = -ENOMEM;
2237 goto out_putdev;
2238 }
2239 pkt_info(pd, "%lukB available on disc\n", lba << 1);
2240 }
2241
2242 return 0;
2243
2244 out_putdev:
2245 blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2246 out:
2247 return ret;
2248 }
2249
2250 /*
2251 * called when the device is closed. makes sure that the device flushes
2252 * the internal cache before we close.
2253 */
2254 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2255 {
2256 if (flush && pkt_flush_cache(pd))
2257 pkt_dbg(1, pd, "not flushing cache\n");
2258
2259 pkt_lock_door(pd, 0);
2260
2261 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2262 blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2263
2264 pkt_shrink_pktlist(pd);
2265 }
2266
2267 static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2268 {
2269 if (dev_minor >= MAX_WRITERS)
2270 return NULL;
2271 return pkt_devs[dev_minor];
2272 }
2273
2274 static int pkt_open(struct block_device *bdev, fmode_t mode)
2275 {
2276 struct pktcdvd_device *pd = NULL;
2277 int ret;
2278
2279 mutex_lock(&pktcdvd_mutex);
2280 mutex_lock(&ctl_mutex);
2281 pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2282 if (!pd) {
2283 ret = -ENODEV;
2284 goto out;
2285 }
2286 BUG_ON(pd->refcnt < 0);
2287
2288 pd->refcnt++;
2289 if (pd->refcnt > 1) {
2290 if ((mode & FMODE_WRITE) &&
2291 !test_bit(PACKET_WRITABLE, &pd->flags)) {
2292 ret = -EBUSY;
2293 goto out_dec;
2294 }
2295 } else {
2296 ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2297 if (ret)
2298 goto out_dec;
2299 /*
2300 * needed here as well, since ext2 (among others) may change
2301 * the blocksize at mount time
2302 */
2303 set_blocksize(bdev, CD_FRAMESIZE);
2304 }
2305
2306 mutex_unlock(&ctl_mutex);
2307 mutex_unlock(&pktcdvd_mutex);
2308 return 0;
2309
2310 out_dec:
2311 pd->refcnt--;
2312 out:
2313 mutex_unlock(&ctl_mutex);
2314 mutex_unlock(&pktcdvd_mutex);
2315 return ret;
2316 }
2317
2318 static void pkt_close(struct gendisk *disk, fmode_t mode)
2319 {
2320 struct pktcdvd_device *pd = disk->private_data;
2321
2322 mutex_lock(&pktcdvd_mutex);
2323 mutex_lock(&ctl_mutex);
2324 pd->refcnt--;
2325 BUG_ON(pd->refcnt < 0);
2326 if (pd->refcnt == 0) {
2327 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2328 pkt_release_dev(pd, flush);
2329 }
2330 mutex_unlock(&ctl_mutex);
2331 mutex_unlock(&pktcdvd_mutex);
2332 }
2333
2334
2335 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2336 {
2337 struct packet_stacked_data *psd = bio->bi_private;
2338 struct pktcdvd_device *pd = psd->pd;
2339
2340 bio_put(bio);
2341 bio_endio(psd->bio, err);
2342 mempool_free(psd, psd_pool);
2343 pkt_bio_finished(pd);
2344 }
2345
2346 static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio)
2347 {
2348 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2349 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2350
2351 psd->pd = pd;
2352 psd->bio = bio;
2353 cloned_bio->bi_bdev = pd->bdev;
2354 cloned_bio->bi_private = psd;
2355 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2356 pd->stats.secs_r += bio_sectors(bio);
2357 pkt_queue_bio(pd, cloned_bio);
2358 }
2359
2360 static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
2361 {
2362 struct pktcdvd_device *pd = q->queuedata;
2363 sector_t zone;
2364 struct packet_data *pkt;
2365 int was_empty, blocked_bio;
2366 struct pkt_rb_node *node;
2367
2368 zone = get_zone(bio->bi_iter.bi_sector, pd);
2369
2370 /*
2371 * If we find a matching packet in state WAITING or READ_WAIT, we can
2372 * just append this bio to that packet.
2373 */
2374 spin_lock(&pd->cdrw.active_list_lock);
2375 blocked_bio = 0;
2376 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2377 if (pkt->sector == zone) {
2378 spin_lock(&pkt->lock);
2379 if ((pkt->state == PACKET_WAITING_STATE) ||
2380 (pkt->state == PACKET_READ_WAIT_STATE)) {
2381 bio_list_add(&pkt->orig_bios, bio);
2382 pkt->write_size +=
2383 bio->bi_iter.bi_size / CD_FRAMESIZE;
2384 if ((pkt->write_size >= pkt->frames) &&
2385 (pkt->state == PACKET_WAITING_STATE)) {
2386 atomic_inc(&pkt->run_sm);
2387 wake_up(&pd->wqueue);
2388 }
2389 spin_unlock(&pkt->lock);
2390 spin_unlock(&pd->cdrw.active_list_lock);
2391 return;
2392 } else {
2393 blocked_bio = 1;
2394 }
2395 spin_unlock(&pkt->lock);
2396 }
2397 }
2398 spin_unlock(&pd->cdrw.active_list_lock);
2399
2400 /*
2401 * Test if there is enough room left in the bio work queue
2402 * (queue size >= congestion on mark).
2403 * If not, wait till the work queue size is below the congestion off mark.
2404 */
2405 spin_lock(&pd->lock);
2406 if (pd->write_congestion_on > 0
2407 && pd->bio_queue_size >= pd->write_congestion_on) {
2408 set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2409 do {
2410 spin_unlock(&pd->lock);
2411 congestion_wait(BLK_RW_ASYNC, HZ);
2412 spin_lock(&pd->lock);
2413 } while(pd->bio_queue_size > pd->write_congestion_off);
2414 }
2415 spin_unlock(&pd->lock);
2416
2417 /*
2418 * No matching packet found. Store the bio in the work queue.
2419 */
2420 node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2421 node->bio = bio;
2422 spin_lock(&pd->lock);
2423 BUG_ON(pd->bio_queue_size < 0);
2424 was_empty = (pd->bio_queue_size == 0);
2425 pkt_rbtree_insert(pd, node);
2426 spin_unlock(&pd->lock);
2427
2428 /*
2429 * Wake up the worker thread.
2430 */
2431 atomic_set(&pd->scan_queue, 1);
2432 if (was_empty) {
2433 /* This wake_up is required for correct operation */
2434 wake_up(&pd->wqueue);
2435 } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2436 /*
2437 * This wake up is not required for correct operation,
2438 * but improves performance in some cases.
2439 */
2440 wake_up(&pd->wqueue);
2441 }
2442 }
2443
2444 static void pkt_make_request(struct request_queue *q, struct bio *bio)
2445 {
2446 struct pktcdvd_device *pd;
2447 char b[BDEVNAME_SIZE];
2448 struct bio *split;
2449
2450 pd = q->queuedata;
2451 if (!pd) {
2452 pr_err("%s incorrect request queue\n",
2453 bdevname(bio->bi_bdev, b));
2454 goto end_io;
2455 }
2456
2457 pkt_dbg(2, pd, "start = %6llx stop = %6llx\n",
2458 (unsigned long long)bio->bi_iter.bi_sector,
2459 (unsigned long long)bio_end_sector(bio));
2460
2461 /*
2462 * Clone READ bios so we can have our own bi_end_io callback.
2463 */
2464 if (bio_data_dir(bio) == READ) {
2465 pkt_make_request_read(pd, bio);
2466 return;
2467 }
2468
2469 if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2470 pkt_notice(pd, "WRITE for ro device (%llu)\n",
2471 (unsigned long long)bio->bi_iter.bi_sector);
2472 goto end_io;
2473 }
2474
2475 if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) {
2476 pkt_err(pd, "wrong bio size\n");
2477 goto end_io;
2478 }
2479
2480 blk_queue_bounce(q, &bio);
2481
2482 do {
2483 sector_t zone = get_zone(bio->bi_iter.bi_sector, pd);
2484 sector_t last_zone = get_zone(bio_end_sector(bio) - 1, pd);
2485
2486 if (last_zone != zone) {
2487 BUG_ON(last_zone != zone + pd->settings.size);
2488
2489 split = bio_split(bio, last_zone -
2490 bio->bi_iter.bi_sector,
2491 GFP_NOIO, fs_bio_set);
2492 bio_chain(split, bio);
2493 } else {
2494 split = bio;
2495 }
2496
2497 pkt_make_request_write(q, split);
2498 } while (split != bio);
2499
2500 return;
2501 end_io:
2502 bio_io_error(bio);
2503 }
2504
2505
2506
2507 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2508 struct bio_vec *bvec)
2509 {
2510 struct pktcdvd_device *pd = q->queuedata;
2511 sector_t zone = get_zone(bmd->bi_sector, pd);
2512 int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2513 int remaining = (pd->settings.size << 9) - used;
2514 int remaining2;
2515
2516 /*
2517 * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2518 * boundary, pkt_make_request() will split the bio.
2519 */
2520 remaining2 = PAGE_SIZE - bmd->bi_size;
2521 remaining = max(remaining, remaining2);
2522
2523 BUG_ON(remaining < 0);
2524 return remaining;
2525 }
2526
2527 static void pkt_init_queue(struct pktcdvd_device *pd)
2528 {
2529 struct request_queue *q = pd->disk->queue;
2530
2531 blk_queue_make_request(q, pkt_make_request);
2532 blk_queue_logical_block_size(q, CD_FRAMESIZE);
2533 blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2534 blk_queue_merge_bvec(q, pkt_merge_bvec);
2535 q->queuedata = pd;
2536 }
2537
2538 static int pkt_seq_show(struct seq_file *m, void *p)
2539 {
2540 struct pktcdvd_device *pd = m->private;
2541 char *msg;
2542 char bdev_buf[BDEVNAME_SIZE];
2543 int states[PACKET_NUM_STATES];
2544
2545 seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2546 bdevname(pd->bdev, bdev_buf));
2547
2548 seq_printf(m, "\nSettings:\n");
2549 seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2550
2551 if (pd->settings.write_type == 0)
2552 msg = "Packet";
2553 else
2554 msg = "Unknown";
2555 seq_printf(m, "\twrite type:\t\t%s\n", msg);
2556
2557 seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2558 seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2559
2560 seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2561
2562 if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2563 msg = "Mode 1";
2564 else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2565 msg = "Mode 2";
2566 else
2567 msg = "Unknown";
2568 seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2569
2570 seq_printf(m, "\nStatistics:\n");
2571 seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2572 seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2573 seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2574 seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2575 seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2576
2577 seq_printf(m, "\nMisc:\n");
2578 seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2579 seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2580 seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2581 seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2582 seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2583 seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2584
2585 seq_printf(m, "\nQueue state:\n");
2586 seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2587 seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2588 seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2589
2590 pkt_count_states(pd, states);
2591 seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2592 states[0], states[1], states[2], states[3], states[4], states[5]);
2593
2594 seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2595 pd->write_congestion_off,
2596 pd->write_congestion_on);
2597 return 0;
2598 }
2599
2600 static int pkt_seq_open(struct inode *inode, struct file *file)
2601 {
2602 return single_open(file, pkt_seq_show, PDE_DATA(inode));
2603 }
2604
2605 static const struct file_operations pkt_proc_fops = {
2606 .open = pkt_seq_open,
2607 .read = seq_read,
2608 .llseek = seq_lseek,
2609 .release = single_release
2610 };
2611
2612 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2613 {
2614 int i;
2615 int ret = 0;
2616 char b[BDEVNAME_SIZE];
2617 struct block_device *bdev;
2618
2619 if (pd->pkt_dev == dev) {
2620 pkt_err(pd, "recursive setup not allowed\n");
2621 return -EBUSY;
2622 }
2623 for (i = 0; i < MAX_WRITERS; i++) {
2624 struct pktcdvd_device *pd2 = pkt_devs[i];
2625 if (!pd2)
2626 continue;
2627 if (pd2->bdev->bd_dev == dev) {
2628 pkt_err(pd, "%s already setup\n",
2629 bdevname(pd2->bdev, b));
2630 return -EBUSY;
2631 }
2632 if (pd2->pkt_dev == dev) {
2633 pkt_err(pd, "can't chain pktcdvd devices\n");
2634 return -EBUSY;
2635 }
2636 }
2637
2638 bdev = bdget(dev);
2639 if (!bdev)
2640 return -ENOMEM;
2641 ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2642 if (ret)
2643 return ret;
2644
2645 /* This is safe, since we have a reference from open(). */
2646 __module_get(THIS_MODULE);
2647
2648 pd->bdev = bdev;
2649 set_blocksize(bdev, CD_FRAMESIZE);
2650
2651 pkt_init_queue(pd);
2652
2653 atomic_set(&pd->cdrw.pending_bios, 0);
2654 pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2655 if (IS_ERR(pd->cdrw.thread)) {
2656 pkt_err(pd, "can't start kernel thread\n");
2657 ret = -ENOMEM;
2658 goto out_mem;
2659 }
2660
2661 proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2662 pkt_dbg(1, pd, "writer mapped to %s\n", bdevname(bdev, b));
2663 return 0;
2664
2665 out_mem:
2666 blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2667 /* This is safe: open() is still holding a reference. */
2668 module_put(THIS_MODULE);
2669 return ret;
2670 }
2671
2672 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2673 {
2674 struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2675 int ret;
2676
2677 pkt_dbg(2, pd, "cmd %x, dev %d:%d\n",
2678 cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2679
2680 mutex_lock(&pktcdvd_mutex);
2681 switch (cmd) {
2682 case CDROMEJECT:
2683 /*
2684 * The door gets locked when the device is opened, so we
2685 * have to unlock it or else the eject command fails.
2686 */
2687 if (pd->refcnt == 1)
2688 pkt_lock_door(pd, 0);
2689 /* fallthru */
2690 /*
2691 * forward selected CDROM ioctls to CD-ROM, for UDF
2692 */
2693 case CDROMMULTISESSION:
2694 case CDROMREADTOCENTRY:
2695 case CDROM_LAST_WRITTEN:
2696 case CDROM_SEND_PACKET:
2697 case SCSI_IOCTL_SEND_COMMAND:
2698 ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2699 break;
2700
2701 default:
2702 pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd);
2703 ret = -ENOTTY;
2704 }
2705 mutex_unlock(&pktcdvd_mutex);
2706
2707 return ret;
2708 }
2709
2710 static unsigned int pkt_check_events(struct gendisk *disk,
2711 unsigned int clearing)
2712 {
2713 struct pktcdvd_device *pd = disk->private_data;
2714 struct gendisk *attached_disk;
2715
2716 if (!pd)
2717 return 0;
2718 if (!pd->bdev)
2719 return 0;
2720 attached_disk = pd->bdev->bd_disk;
2721 if (!attached_disk || !attached_disk->fops->check_events)
2722 return 0;
2723 return attached_disk->fops->check_events(attached_disk, clearing);
2724 }
2725
2726 static const struct block_device_operations pktcdvd_ops = {
2727 .owner = THIS_MODULE,
2728 .open = pkt_open,
2729 .release = pkt_close,
2730 .ioctl = pkt_ioctl,
2731 .check_events = pkt_check_events,
2732 };
2733
2734 static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
2735 {
2736 return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2737 }
2738
2739 /*
2740 * Set up mapping from pktcdvd device to CD-ROM device.
2741 */
2742 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2743 {
2744 int idx;
2745 int ret = -ENOMEM;
2746 struct pktcdvd_device *pd;
2747 struct gendisk *disk;
2748
2749 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2750
2751 for (idx = 0; idx < MAX_WRITERS; idx++)
2752 if (!pkt_devs[idx])
2753 break;
2754 if (idx == MAX_WRITERS) {
2755 pr_err("max %d writers supported\n", MAX_WRITERS);
2756 ret = -EBUSY;
2757 goto out_mutex;
2758 }
2759
2760 pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2761 if (!pd)
2762 goto out_mutex;
2763
2764 pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2765 sizeof(struct pkt_rb_node));
2766 if (!pd->rb_pool)
2767 goto out_mem;
2768
2769 INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2770 INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2771 spin_lock_init(&pd->cdrw.active_list_lock);
2772
2773 spin_lock_init(&pd->lock);
2774 spin_lock_init(&pd->iosched.lock);
2775 bio_list_init(&pd->iosched.read_queue);
2776 bio_list_init(&pd->iosched.write_queue);
2777 sprintf(pd->name, DRIVER_NAME"%d", idx);
2778 init_waitqueue_head(&pd->wqueue);
2779 pd->bio_queue = RB_ROOT;
2780
2781 pd->write_congestion_on = write_congestion_on;
2782 pd->write_congestion_off = write_congestion_off;
2783
2784 disk = alloc_disk(1);
2785 if (!disk)
2786 goto out_mem;
2787 pd->disk = disk;
2788 disk->major = pktdev_major;
2789 disk->first_minor = idx;
2790 disk->fops = &pktcdvd_ops;
2791 disk->flags = GENHD_FL_REMOVABLE;
2792 strcpy(disk->disk_name, pd->name);
2793 disk->devnode = pktcdvd_devnode;
2794 disk->private_data = pd;
2795 disk->queue = blk_alloc_queue(GFP_KERNEL);
2796 if (!disk->queue)
2797 goto out_mem2;
2798
2799 pd->pkt_dev = MKDEV(pktdev_major, idx);
2800 ret = pkt_new_dev(pd, dev);
2801 if (ret)
2802 goto out_new_dev;
2803
2804 /* inherit events of the host device */
2805 disk->events = pd->bdev->bd_disk->events;
2806 disk->async_events = pd->bdev->bd_disk->async_events;
2807
2808 add_disk(disk);
2809
2810 pkt_sysfs_dev_new(pd);
2811 pkt_debugfs_dev_new(pd);
2812
2813 pkt_devs[idx] = pd;
2814 if (pkt_dev)
2815 *pkt_dev = pd->pkt_dev;
2816
2817 mutex_unlock(&ctl_mutex);
2818 return 0;
2819
2820 out_new_dev:
2821 blk_cleanup_queue(disk->queue);
2822 out_mem2:
2823 put_disk(disk);
2824 out_mem:
2825 if (pd->rb_pool)
2826 mempool_destroy(pd->rb_pool);
2827 kfree(pd);
2828 out_mutex:
2829 mutex_unlock(&ctl_mutex);
2830 pr_err("setup of pktcdvd device failed\n");
2831 return ret;
2832 }
2833
2834 /*
2835 * Tear down mapping from pktcdvd device to CD-ROM device.
2836 */
2837 static int pkt_remove_dev(dev_t pkt_dev)
2838 {
2839 struct pktcdvd_device *pd;
2840 int idx;
2841 int ret = 0;
2842
2843 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2844
2845 for (idx = 0; idx < MAX_WRITERS; idx++) {
2846 pd = pkt_devs[idx];
2847 if (pd && (pd->pkt_dev == pkt_dev))
2848 break;
2849 }
2850 if (idx == MAX_WRITERS) {
2851 pr_debug("dev not setup\n");
2852 ret = -ENXIO;
2853 goto out;
2854 }
2855
2856 if (pd->refcnt > 0) {
2857 ret = -EBUSY;
2858 goto out;
2859 }
2860 if (!IS_ERR(pd->cdrw.thread))
2861 kthread_stop(pd->cdrw.thread);
2862
2863 pkt_devs[idx] = NULL;
2864
2865 pkt_debugfs_dev_remove(pd);
2866 pkt_sysfs_dev_remove(pd);
2867
2868 blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2869
2870 remove_proc_entry(pd->name, pkt_proc);
2871 pkt_dbg(1, pd, "writer unmapped\n");
2872
2873 del_gendisk(pd->disk);
2874 blk_cleanup_queue(pd->disk->queue);
2875 put_disk(pd->disk);
2876
2877 mempool_destroy(pd->rb_pool);
2878 kfree(pd);
2879
2880 /* This is safe: open() is still holding a reference. */
2881 module_put(THIS_MODULE);
2882
2883 out:
2884 mutex_unlock(&ctl_mutex);
2885 return ret;
2886 }
2887
2888 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2889 {
2890 struct pktcdvd_device *pd;
2891
2892 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2893
2894 pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2895 if (pd) {
2896 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2897 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2898 } else {
2899 ctrl_cmd->dev = 0;
2900 ctrl_cmd->pkt_dev = 0;
2901 }
2902 ctrl_cmd->num_devices = MAX_WRITERS;
2903
2904 mutex_unlock(&ctl_mutex);
2905 }
2906
2907 static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2908 {
2909 void __user *argp = (void __user *)arg;
2910 struct pkt_ctrl_command ctrl_cmd;
2911 int ret = 0;
2912 dev_t pkt_dev = 0;
2913
2914 if (cmd != PACKET_CTRL_CMD)
2915 return -ENOTTY;
2916
2917 if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2918 return -EFAULT;
2919
2920 switch (ctrl_cmd.command) {
2921 case PKT_CTRL_CMD_SETUP:
2922 if (!capable(CAP_SYS_ADMIN))
2923 return -EPERM;
2924 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2925 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2926 break;
2927 case PKT_CTRL_CMD_TEARDOWN:
2928 if (!capable(CAP_SYS_ADMIN))
2929 return -EPERM;
2930 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2931 break;
2932 case PKT_CTRL_CMD_STATUS:
2933 pkt_get_status(&ctrl_cmd);
2934 break;
2935 default:
2936 return -ENOTTY;
2937 }
2938
2939 if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2940 return -EFAULT;
2941 return ret;
2942 }
2943
2944 #ifdef CONFIG_COMPAT
2945 static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2946 {
2947 return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2948 }
2949 #endif
2950
2951 static const struct file_operations pkt_ctl_fops = {
2952 .open = nonseekable_open,
2953 .unlocked_ioctl = pkt_ctl_ioctl,
2954 #ifdef CONFIG_COMPAT
2955 .compat_ioctl = pkt_ctl_compat_ioctl,
2956 #endif
2957 .owner = THIS_MODULE,
2958 .llseek = no_llseek,
2959 };
2960
2961 static struct miscdevice pkt_misc = {
2962 .minor = MISC_DYNAMIC_MINOR,
2963 .name = DRIVER_NAME,
2964 .nodename = "pktcdvd/control",
2965 .fops = &pkt_ctl_fops
2966 };
2967
2968 static int __init pkt_init(void)
2969 {
2970 int ret;
2971
2972 mutex_init(&ctl_mutex);
2973
2974 psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
2975 sizeof(struct packet_stacked_data));
2976 if (!psd_pool)
2977 return -ENOMEM;
2978
2979 ret = register_blkdev(pktdev_major, DRIVER_NAME);
2980 if (ret < 0) {
2981 pr_err("unable to register block device\n");
2982 goto out2;
2983 }
2984 if (!pktdev_major)
2985 pktdev_major = ret;
2986
2987 ret = pkt_sysfs_init();
2988 if (ret)
2989 goto out;
2990
2991 pkt_debugfs_init();
2992
2993 ret = misc_register(&pkt_misc);
2994 if (ret) {
2995 pr_err("unable to register misc device\n");
2996 goto out_misc;
2997 }
2998
2999 pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
3000
3001 return 0;
3002
3003 out_misc:
3004 pkt_debugfs_cleanup();
3005 pkt_sysfs_cleanup();
3006 out:
3007 unregister_blkdev(pktdev_major, DRIVER_NAME);
3008 out2:
3009 mempool_destroy(psd_pool);
3010 return ret;
3011 }
3012
3013 static void __exit pkt_exit(void)
3014 {
3015 remove_proc_entry("driver/"DRIVER_NAME, NULL);
3016 misc_deregister(&pkt_misc);
3017
3018 pkt_debugfs_cleanup();
3019 pkt_sysfs_cleanup();
3020
3021 unregister_blkdev(pktdev_major, DRIVER_NAME);
3022 mempool_destroy(psd_pool);
3023 }
3024
3025 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3026 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3027 MODULE_LICENSE("GPL");
3028
3029 module_init(pkt_init);
3030 module_exit(pkt_exit);
Ubuntu Artful kernel mirror