xref: /openbmc/linux/drivers/block/pktcdvd.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
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) & ~((pd)->settings.size - 1))
87 
88 static DEFINE_MUTEX(pktcdvd_mutex);
89 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
90 static struct proc_dir_entry *pkt_proc;
91 static int pktdev_major;
92 static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
93 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
94 static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
95 static mempool_t *psd_pool;
96 
97 static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
98 static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
99 
100 /* forward declaration */
101 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
102 static int pkt_remove_dev(dev_t pkt_dev);
103 static int pkt_seq_show(struct seq_file *m, void *p);
104 
105 
106 
107 /*
108  * create and register a pktcdvd kernel object.
109  */
110 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
111 					const char* name,
112 					struct kobject* parent,
113 					struct kobj_type* ktype)
114 {
115 	struct pktcdvd_kobj *p;
116 	int error;
117 
118 	p = kzalloc(sizeof(*p), GFP_KERNEL);
119 	if (!p)
120 		return NULL;
121 	p->pd = pd;
122 	error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
123 	if (error) {
124 		kobject_put(&p->kobj);
125 		return NULL;
126 	}
127 	kobject_uevent(&p->kobj, KOBJ_ADD);
128 	return p;
129 }
130 /*
131  * remove a pktcdvd kernel object.
132  */
133 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
134 {
135 	if (p)
136 		kobject_put(&p->kobj);
137 }
138 /*
139  * default release function for pktcdvd kernel objects.
140  */
141 static void pkt_kobj_release(struct kobject *kobj)
142 {
143 	kfree(to_pktcdvdkobj(kobj));
144 }
145 
146 
147 /**********************************************************
148  *
149  * sysfs interface for pktcdvd
150  * by (C) 2006  Thomas Maier <balagi@justmail.de>
151  *
152  **********************************************************/
153 
154 #define DEF_ATTR(_obj,_name,_mode) \
155 	static struct attribute _obj = { .name = _name, .mode = _mode }
156 
157 /**********************************************************
158   /sys/class/pktcdvd/pktcdvd[0-7]/
159                      stat/reset
160                      stat/packets_started
161                      stat/packets_finished
162                      stat/kb_written
163                      stat/kb_read
164                      stat/kb_read_gather
165                      write_queue/size
166                      write_queue/congestion_off
167                      write_queue/congestion_on
168  **********************************************************/
169 
170 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
171 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
172 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
173 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
174 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
175 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
176 
177 static struct attribute *kobj_pkt_attrs_stat[] = {
178 	&kobj_pkt_attr_st1,
179 	&kobj_pkt_attr_st2,
180 	&kobj_pkt_attr_st3,
181 	&kobj_pkt_attr_st4,
182 	&kobj_pkt_attr_st5,
183 	&kobj_pkt_attr_st6,
184 	NULL
185 };
186 
187 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
188 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
189 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
190 
191 static struct attribute *kobj_pkt_attrs_wqueue[] = {
192 	&kobj_pkt_attr_wq1,
193 	&kobj_pkt_attr_wq2,
194 	&kobj_pkt_attr_wq3,
195 	NULL
196 };
197 
198 static ssize_t kobj_pkt_show(struct kobject *kobj,
199 			struct attribute *attr, char *data)
200 {
201 	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
202 	int n = 0;
203 	int v;
204 	if (strcmp(attr->name, "packets_started") == 0) {
205 		n = sprintf(data, "%lu\n", pd->stats.pkt_started);
206 
207 	} else if (strcmp(attr->name, "packets_finished") == 0) {
208 		n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
209 
210 	} else if (strcmp(attr->name, "kb_written") == 0) {
211 		n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
212 
213 	} else if (strcmp(attr->name, "kb_read") == 0) {
214 		n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
215 
216 	} else if (strcmp(attr->name, "kb_read_gather") == 0) {
217 		n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
218 
219 	} else if (strcmp(attr->name, "size") == 0) {
220 		spin_lock(&pd->lock);
221 		v = pd->bio_queue_size;
222 		spin_unlock(&pd->lock);
223 		n = sprintf(data, "%d\n", v);
224 
225 	} else if (strcmp(attr->name, "congestion_off") == 0) {
226 		spin_lock(&pd->lock);
227 		v = pd->write_congestion_off;
228 		spin_unlock(&pd->lock);
229 		n = sprintf(data, "%d\n", v);
230 
231 	} else if (strcmp(attr->name, "congestion_on") == 0) {
232 		spin_lock(&pd->lock);
233 		v = pd->write_congestion_on;
234 		spin_unlock(&pd->lock);
235 		n = sprintf(data, "%d\n", v);
236 	}
237 	return n;
238 }
239 
240 static void init_write_congestion_marks(int* lo, int* hi)
241 {
242 	if (*hi > 0) {
243 		*hi = max(*hi, 500);
244 		*hi = min(*hi, 1000000);
245 		if (*lo <= 0)
246 			*lo = *hi - 100;
247 		else {
248 			*lo = min(*lo, *hi - 100);
249 			*lo = max(*lo, 100);
250 		}
251 	} else {
252 		*hi = -1;
253 		*lo = -1;
254 	}
255 }
256 
257 static ssize_t kobj_pkt_store(struct kobject *kobj,
258 			struct attribute *attr,
259 			const char *data, size_t len)
260 {
261 	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
262 	int val;
263 
264 	if (strcmp(attr->name, "reset") == 0 && len > 0) {
265 		pd->stats.pkt_started = 0;
266 		pd->stats.pkt_ended = 0;
267 		pd->stats.secs_w = 0;
268 		pd->stats.secs_rg = 0;
269 		pd->stats.secs_r = 0;
270 
271 	} else if (strcmp(attr->name, "congestion_off") == 0
272 		   && sscanf(data, "%d", &val) == 1) {
273 		spin_lock(&pd->lock);
274 		pd->write_congestion_off = val;
275 		init_write_congestion_marks(&pd->write_congestion_off,
276 					&pd->write_congestion_on);
277 		spin_unlock(&pd->lock);
278 
279 	} else if (strcmp(attr->name, "congestion_on") == 0
280 		   && sscanf(data, "%d", &val) == 1) {
281 		spin_lock(&pd->lock);
282 		pd->write_congestion_on = val;
283 		init_write_congestion_marks(&pd->write_congestion_off,
284 					&pd->write_congestion_on);
285 		spin_unlock(&pd->lock);
286 	}
287 	return len;
288 }
289 
290 static const struct sysfs_ops kobj_pkt_ops = {
291 	.show = kobj_pkt_show,
292 	.store = kobj_pkt_store
293 };
294 static struct kobj_type kobj_pkt_type_stat = {
295 	.release = pkt_kobj_release,
296 	.sysfs_ops = &kobj_pkt_ops,
297 	.default_attrs = kobj_pkt_attrs_stat
298 };
299 static struct kobj_type kobj_pkt_type_wqueue = {
300 	.release = pkt_kobj_release,
301 	.sysfs_ops = &kobj_pkt_ops,
302 	.default_attrs = kobj_pkt_attrs_wqueue
303 };
304 
305 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
306 {
307 	if (class_pktcdvd) {
308 		pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
309 					"%s", pd->name);
310 		if (IS_ERR(pd->dev))
311 			pd->dev = NULL;
312 	}
313 	if (pd->dev) {
314 		pd->kobj_stat = pkt_kobj_create(pd, "stat",
315 					&pd->dev->kobj,
316 					&kobj_pkt_type_stat);
317 		pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
318 					&pd->dev->kobj,
319 					&kobj_pkt_type_wqueue);
320 	}
321 }
322 
323 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
324 {
325 	pkt_kobj_remove(pd->kobj_stat);
326 	pkt_kobj_remove(pd->kobj_wqueue);
327 	if (class_pktcdvd)
328 		device_unregister(pd->dev);
329 }
330 
331 
332 /********************************************************************
333   /sys/class/pktcdvd/
334                      add            map block device
335                      remove         unmap packet dev
336                      device_map     show mappings
337  *******************************************************************/
338 
339 static void class_pktcdvd_release(struct class *cls)
340 {
341 	kfree(cls);
342 }
343 static ssize_t class_pktcdvd_show_map(struct class *c,
344 					struct class_attribute *attr,
345 					char *data)
346 {
347 	int n = 0;
348 	int idx;
349 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
350 	for (idx = 0; idx < MAX_WRITERS; idx++) {
351 		struct pktcdvd_device *pd = pkt_devs[idx];
352 		if (!pd)
353 			continue;
354 		n += sprintf(data+n, "%s %u:%u %u:%u\n",
355 			pd->name,
356 			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
357 			MAJOR(pd->bdev->bd_dev),
358 			MINOR(pd->bdev->bd_dev));
359 	}
360 	mutex_unlock(&ctl_mutex);
361 	return n;
362 }
363 
364 static ssize_t class_pktcdvd_store_add(struct class *c,
365 					struct class_attribute *attr,
366 					const char *buf,
367 					size_t count)
368 {
369 	unsigned int major, minor;
370 
371 	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
372 		/* pkt_setup_dev() expects caller to hold reference to self */
373 		if (!try_module_get(THIS_MODULE))
374 			return -ENODEV;
375 
376 		pkt_setup_dev(MKDEV(major, minor), NULL);
377 
378 		module_put(THIS_MODULE);
379 
380 		return count;
381 	}
382 
383 	return -EINVAL;
384 }
385 
386 static ssize_t class_pktcdvd_store_remove(struct class *c,
387 					  struct class_attribute *attr,
388 					  const char *buf,
389 					size_t count)
390 {
391 	unsigned int major, minor;
392 	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
393 		pkt_remove_dev(MKDEV(major, minor));
394 		return count;
395 	}
396 	return -EINVAL;
397 }
398 
399 static struct class_attribute class_pktcdvd_attrs[] = {
400  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
401  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
402  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
403  __ATTR_NULL
404 };
405 
406 
407 static int pkt_sysfs_init(void)
408 {
409 	int ret = 0;
410 
411 	/*
412 	 * create control files in sysfs
413 	 * /sys/class/pktcdvd/...
414 	 */
415 	class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
416 	if (!class_pktcdvd)
417 		return -ENOMEM;
418 	class_pktcdvd->name = DRIVER_NAME;
419 	class_pktcdvd->owner = THIS_MODULE;
420 	class_pktcdvd->class_release = class_pktcdvd_release;
421 	class_pktcdvd->class_attrs = class_pktcdvd_attrs;
422 	ret = class_register(class_pktcdvd);
423 	if (ret) {
424 		kfree(class_pktcdvd);
425 		class_pktcdvd = NULL;
426 		printk(DRIVER_NAME": failed to create class pktcdvd\n");
427 		return ret;
428 	}
429 	return 0;
430 }
431 
432 static void pkt_sysfs_cleanup(void)
433 {
434 	if (class_pktcdvd)
435 		class_destroy(class_pktcdvd);
436 	class_pktcdvd = NULL;
437 }
438 
439 /********************************************************************
440   entries in debugfs
441 
442   /sys/kernel/debug/pktcdvd[0-7]/
443 			info
444 
445  *******************************************************************/
446 
447 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
448 {
449 	return pkt_seq_show(m, p);
450 }
451 
452 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
453 {
454 	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
455 }
456 
457 static const struct file_operations debug_fops = {
458 	.open		= pkt_debugfs_fops_open,
459 	.read		= seq_read,
460 	.llseek		= seq_lseek,
461 	.release	= single_release,
462 	.owner		= THIS_MODULE,
463 };
464 
465 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
466 {
467 	if (!pkt_debugfs_root)
468 		return;
469 	pd->dfs_f_info = NULL;
470 	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
471 	if (IS_ERR(pd->dfs_d_root)) {
472 		pd->dfs_d_root = NULL;
473 		return;
474 	}
475 	pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
476 				pd->dfs_d_root, pd, &debug_fops);
477 	if (IS_ERR(pd->dfs_f_info)) {
478 		pd->dfs_f_info = NULL;
479 		return;
480 	}
481 }
482 
483 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
484 {
485 	if (!pkt_debugfs_root)
486 		return;
487 	if (pd->dfs_f_info)
488 		debugfs_remove(pd->dfs_f_info);
489 	pd->dfs_f_info = NULL;
490 	if (pd->dfs_d_root)
491 		debugfs_remove(pd->dfs_d_root);
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 	if (IS_ERR(pkt_debugfs_root)) {
499 		pkt_debugfs_root = NULL;
500 		return;
501 	}
502 }
503 
504 static void pkt_debugfs_cleanup(void)
505 {
506 	if (!pkt_debugfs_root)
507 		return;
508 	debugfs_remove(pkt_debugfs_root);
509 	pkt_debugfs_root = NULL;
510 }
511 
512 /* ----------------------------------------------------------*/
513 
514 
515 static void pkt_bio_finished(struct pktcdvd_device *pd)
516 {
517 	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
518 	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
519 		VPRINTK(DRIVER_NAME": queue empty\n");
520 		atomic_set(&pd->iosched.attention, 1);
521 		wake_up(&pd->wqueue);
522 	}
523 }
524 
525 static void pkt_bio_destructor(struct bio *bio)
526 {
527 	kfree(bio->bi_io_vec);
528 	kfree(bio);
529 }
530 
531 static struct bio *pkt_bio_alloc(int nr_iovecs)
532 {
533 	struct bio_vec *bvl = NULL;
534 	struct bio *bio;
535 
536 	bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
537 	if (!bio)
538 		goto no_bio;
539 	bio_init(bio);
540 
541 	bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL);
542 	if (!bvl)
543 		goto no_bvl;
544 
545 	bio->bi_max_vecs = nr_iovecs;
546 	bio->bi_io_vec = bvl;
547 	bio->bi_destructor = pkt_bio_destructor;
548 
549 	return bio;
550 
551  no_bvl:
552 	kfree(bio);
553  no_bio:
554 	return NULL;
555 }
556 
557 /*
558  * Allocate a packet_data struct
559  */
560 static struct packet_data *pkt_alloc_packet_data(int frames)
561 {
562 	int i;
563 	struct packet_data *pkt;
564 
565 	pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
566 	if (!pkt)
567 		goto no_pkt;
568 
569 	pkt->frames = frames;
570 	pkt->w_bio = pkt_bio_alloc(frames);
571 	if (!pkt->w_bio)
572 		goto no_bio;
573 
574 	for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
575 		pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
576 		if (!pkt->pages[i])
577 			goto no_page;
578 	}
579 
580 	spin_lock_init(&pkt->lock);
581 	bio_list_init(&pkt->orig_bios);
582 
583 	for (i = 0; i < frames; i++) {
584 		struct bio *bio = pkt_bio_alloc(1);
585 		if (!bio)
586 			goto no_rd_bio;
587 		pkt->r_bios[i] = bio;
588 	}
589 
590 	return pkt;
591 
592 no_rd_bio:
593 	for (i = 0; i < frames; i++) {
594 		struct bio *bio = pkt->r_bios[i];
595 		if (bio)
596 			bio_put(bio);
597 	}
598 
599 no_page:
600 	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
601 		if (pkt->pages[i])
602 			__free_page(pkt->pages[i]);
603 	bio_put(pkt->w_bio);
604 no_bio:
605 	kfree(pkt);
606 no_pkt:
607 	return NULL;
608 }
609 
610 /*
611  * Free a packet_data struct
612  */
613 static void pkt_free_packet_data(struct packet_data *pkt)
614 {
615 	int i;
616 
617 	for (i = 0; i < pkt->frames; i++) {
618 		struct bio *bio = pkt->r_bios[i];
619 		if (bio)
620 			bio_put(bio);
621 	}
622 	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
623 		__free_page(pkt->pages[i]);
624 	bio_put(pkt->w_bio);
625 	kfree(pkt);
626 }
627 
628 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
629 {
630 	struct packet_data *pkt, *next;
631 
632 	BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
633 
634 	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
635 		pkt_free_packet_data(pkt);
636 	}
637 	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
638 }
639 
640 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
641 {
642 	struct packet_data *pkt;
643 
644 	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
645 
646 	while (nr_packets > 0) {
647 		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
648 		if (!pkt) {
649 			pkt_shrink_pktlist(pd);
650 			return 0;
651 		}
652 		pkt->id = nr_packets;
653 		pkt->pd = pd;
654 		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
655 		nr_packets--;
656 	}
657 	return 1;
658 }
659 
660 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
661 {
662 	struct rb_node *n = rb_next(&node->rb_node);
663 	if (!n)
664 		return NULL;
665 	return rb_entry(n, struct pkt_rb_node, rb_node);
666 }
667 
668 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
669 {
670 	rb_erase(&node->rb_node, &pd->bio_queue);
671 	mempool_free(node, pd->rb_pool);
672 	pd->bio_queue_size--;
673 	BUG_ON(pd->bio_queue_size < 0);
674 }
675 
676 /*
677  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
678  */
679 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
680 {
681 	struct rb_node *n = pd->bio_queue.rb_node;
682 	struct rb_node *next;
683 	struct pkt_rb_node *tmp;
684 
685 	if (!n) {
686 		BUG_ON(pd->bio_queue_size > 0);
687 		return NULL;
688 	}
689 
690 	for (;;) {
691 		tmp = rb_entry(n, struct pkt_rb_node, rb_node);
692 		if (s <= tmp->bio->bi_sector)
693 			next = n->rb_left;
694 		else
695 			next = n->rb_right;
696 		if (!next)
697 			break;
698 		n = next;
699 	}
700 
701 	if (s > tmp->bio->bi_sector) {
702 		tmp = pkt_rbtree_next(tmp);
703 		if (!tmp)
704 			return NULL;
705 	}
706 	BUG_ON(s > tmp->bio->bi_sector);
707 	return tmp;
708 }
709 
710 /*
711  * Insert a node into the pd->bio_queue rb tree.
712  */
713 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
714 {
715 	struct rb_node **p = &pd->bio_queue.rb_node;
716 	struct rb_node *parent = NULL;
717 	sector_t s = node->bio->bi_sector;
718 	struct pkt_rb_node *tmp;
719 
720 	while (*p) {
721 		parent = *p;
722 		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
723 		if (s < tmp->bio->bi_sector)
724 			p = &(*p)->rb_left;
725 		else
726 			p = &(*p)->rb_right;
727 	}
728 	rb_link_node(&node->rb_node, parent, p);
729 	rb_insert_color(&node->rb_node, &pd->bio_queue);
730 	pd->bio_queue_size++;
731 }
732 
733 /*
734  * Send a packet_command to the underlying block device and
735  * wait for completion.
736  */
737 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
738 {
739 	struct request_queue *q = bdev_get_queue(pd->bdev);
740 	struct request *rq;
741 	int ret = 0;
742 
743 	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
744 			     WRITE : READ, __GFP_WAIT);
745 
746 	if (cgc->buflen) {
747 		if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
748 			goto out;
749 	}
750 
751 	rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
752 	memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
753 
754 	rq->timeout = 60*HZ;
755 	rq->cmd_type = REQ_TYPE_BLOCK_PC;
756 	if (cgc->quiet)
757 		rq->cmd_flags |= REQ_QUIET;
758 
759 	blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
760 	if (rq->errors)
761 		ret = -EIO;
762 out:
763 	blk_put_request(rq);
764 	return ret;
765 }
766 
767 /*
768  * A generic sense dump / resolve mechanism should be implemented across
769  * all ATAPI + SCSI devices.
770  */
771 static void pkt_dump_sense(struct packet_command *cgc)
772 {
773 	static char *info[9] = { "No sense", "Recovered error", "Not ready",
774 				 "Medium error", "Hardware error", "Illegal request",
775 				 "Unit attention", "Data protect", "Blank check" };
776 	int i;
777 	struct request_sense *sense = cgc->sense;
778 
779 	printk(DRIVER_NAME":");
780 	for (i = 0; i < CDROM_PACKET_SIZE; i++)
781 		printk(" %02x", cgc->cmd[i]);
782 	printk(" - ");
783 
784 	if (sense == NULL) {
785 		printk("no sense\n");
786 		return;
787 	}
788 
789 	printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
790 
791 	if (sense->sense_key > 8) {
792 		printk(" (INVALID)\n");
793 		return;
794 	}
795 
796 	printk(" (%s)\n", info[sense->sense_key]);
797 }
798 
799 /*
800  * flush the drive cache to media
801  */
802 static int pkt_flush_cache(struct pktcdvd_device *pd)
803 {
804 	struct packet_command cgc;
805 
806 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
807 	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
808 	cgc.quiet = 1;
809 
810 	/*
811 	 * the IMMED bit -- we default to not setting it, although that
812 	 * would allow a much faster close, this is safer
813 	 */
814 #if 0
815 	cgc.cmd[1] = 1 << 1;
816 #endif
817 	return pkt_generic_packet(pd, &cgc);
818 }
819 
820 /*
821  * speed is given as the normal factor, e.g. 4 for 4x
822  */
823 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
824 				unsigned write_speed, unsigned read_speed)
825 {
826 	struct packet_command cgc;
827 	struct request_sense sense;
828 	int ret;
829 
830 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
831 	cgc.sense = &sense;
832 	cgc.cmd[0] = GPCMD_SET_SPEED;
833 	cgc.cmd[2] = (read_speed >> 8) & 0xff;
834 	cgc.cmd[3] = read_speed & 0xff;
835 	cgc.cmd[4] = (write_speed >> 8) & 0xff;
836 	cgc.cmd[5] = write_speed & 0xff;
837 
838 	if ((ret = pkt_generic_packet(pd, &cgc)))
839 		pkt_dump_sense(&cgc);
840 
841 	return ret;
842 }
843 
844 /*
845  * Queue a bio for processing by the low-level CD device. Must be called
846  * from process context.
847  */
848 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
849 {
850 	spin_lock(&pd->iosched.lock);
851 	if (bio_data_dir(bio) == READ)
852 		bio_list_add(&pd->iosched.read_queue, bio);
853 	else
854 		bio_list_add(&pd->iosched.write_queue, bio);
855 	spin_unlock(&pd->iosched.lock);
856 
857 	atomic_set(&pd->iosched.attention, 1);
858 	wake_up(&pd->wqueue);
859 }
860 
861 /*
862  * Process the queued read/write requests. This function handles special
863  * requirements for CDRW drives:
864  * - A cache flush command must be inserted before a read request if the
865  *   previous request was a write.
866  * - Switching between reading and writing is slow, so don't do it more often
867  *   than necessary.
868  * - Optimize for throughput at the expense of latency. This means that streaming
869  *   writes will never be interrupted by a read, but if the drive has to seek
870  *   before the next write, switch to reading instead if there are any pending
871  *   read requests.
872  * - Set the read speed according to current usage pattern. When only reading
873  *   from the device, it's best to use the highest possible read speed, but
874  *   when switching often between reading and writing, it's better to have the
875  *   same read and write speeds.
876  */
877 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
878 {
879 
880 	if (atomic_read(&pd->iosched.attention) == 0)
881 		return;
882 	atomic_set(&pd->iosched.attention, 0);
883 
884 	for (;;) {
885 		struct bio *bio;
886 		int reads_queued, writes_queued;
887 
888 		spin_lock(&pd->iosched.lock);
889 		reads_queued = !bio_list_empty(&pd->iosched.read_queue);
890 		writes_queued = !bio_list_empty(&pd->iosched.write_queue);
891 		spin_unlock(&pd->iosched.lock);
892 
893 		if (!reads_queued && !writes_queued)
894 			break;
895 
896 		if (pd->iosched.writing) {
897 			int need_write_seek = 1;
898 			spin_lock(&pd->iosched.lock);
899 			bio = bio_list_peek(&pd->iosched.write_queue);
900 			spin_unlock(&pd->iosched.lock);
901 			if (bio && (bio->bi_sector == pd->iosched.last_write))
902 				need_write_seek = 0;
903 			if (need_write_seek && reads_queued) {
904 				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
905 					VPRINTK(DRIVER_NAME": write, waiting\n");
906 					break;
907 				}
908 				pkt_flush_cache(pd);
909 				pd->iosched.writing = 0;
910 			}
911 		} else {
912 			if (!reads_queued && writes_queued) {
913 				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
914 					VPRINTK(DRIVER_NAME": read, waiting\n");
915 					break;
916 				}
917 				pd->iosched.writing = 1;
918 			}
919 		}
920 
921 		spin_lock(&pd->iosched.lock);
922 		if (pd->iosched.writing)
923 			bio = bio_list_pop(&pd->iosched.write_queue);
924 		else
925 			bio = bio_list_pop(&pd->iosched.read_queue);
926 		spin_unlock(&pd->iosched.lock);
927 
928 		if (!bio)
929 			continue;
930 
931 		if (bio_data_dir(bio) == READ)
932 			pd->iosched.successive_reads += bio->bi_size >> 10;
933 		else {
934 			pd->iosched.successive_reads = 0;
935 			pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
936 		}
937 		if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
938 			if (pd->read_speed == pd->write_speed) {
939 				pd->read_speed = MAX_SPEED;
940 				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
941 			}
942 		} else {
943 			if (pd->read_speed != pd->write_speed) {
944 				pd->read_speed = pd->write_speed;
945 				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
946 			}
947 		}
948 
949 		atomic_inc(&pd->cdrw.pending_bios);
950 		generic_make_request(bio);
951 	}
952 }
953 
954 /*
955  * Special care is needed if the underlying block device has a small
956  * max_phys_segments value.
957  */
958 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
959 {
960 	if ((pd->settings.size << 9) / CD_FRAMESIZE
961 	    <= queue_max_segments(q)) {
962 		/*
963 		 * The cdrom device can handle one segment/frame
964 		 */
965 		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
966 		return 0;
967 	} else if ((pd->settings.size << 9) / PAGE_SIZE
968 		   <= queue_max_segments(q)) {
969 		/*
970 		 * We can handle this case at the expense of some extra memory
971 		 * copies during write operations
972 		 */
973 		set_bit(PACKET_MERGE_SEGS, &pd->flags);
974 		return 0;
975 	} else {
976 		printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
977 		return -EIO;
978 	}
979 }
980 
981 /*
982  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
983  */
984 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
985 {
986 	unsigned int copy_size = CD_FRAMESIZE;
987 
988 	while (copy_size > 0) {
989 		struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
990 		void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
991 			src_bvl->bv_offset + offs;
992 		void *vto = page_address(dst_page) + dst_offs;
993 		int len = min_t(int, copy_size, src_bvl->bv_len - offs);
994 
995 		BUG_ON(len < 0);
996 		memcpy(vto, vfrom, len);
997 		kunmap_atomic(vfrom, KM_USER0);
998 
999 		seg++;
1000 		offs = 0;
1001 		dst_offs += len;
1002 		copy_size -= len;
1003 	}
1004 }
1005 
1006 /*
1007  * Copy all data for this packet to pkt->pages[], so that
1008  * a) The number of required segments for the write bio is minimized, which
1009  *    is necessary for some scsi controllers.
1010  * b) The data can be used as cache to avoid read requests if we receive a
1011  *    new write request for the same zone.
1012  */
1013 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
1014 {
1015 	int f, p, offs;
1016 
1017 	/* Copy all data to pkt->pages[] */
1018 	p = 0;
1019 	offs = 0;
1020 	for (f = 0; f < pkt->frames; f++) {
1021 		if (bvec[f].bv_page != pkt->pages[p]) {
1022 			void *vfrom = kmap_atomic(bvec[f].bv_page, KM_USER0) + bvec[f].bv_offset;
1023 			void *vto = page_address(pkt->pages[p]) + offs;
1024 			memcpy(vto, vfrom, CD_FRAMESIZE);
1025 			kunmap_atomic(vfrom, KM_USER0);
1026 			bvec[f].bv_page = pkt->pages[p];
1027 			bvec[f].bv_offset = offs;
1028 		} else {
1029 			BUG_ON(bvec[f].bv_offset != offs);
1030 		}
1031 		offs += CD_FRAMESIZE;
1032 		if (offs >= PAGE_SIZE) {
1033 			offs = 0;
1034 			p++;
1035 		}
1036 	}
1037 }
1038 
1039 static void pkt_end_io_read(struct bio *bio, int err)
1040 {
1041 	struct packet_data *pkt = bio->bi_private;
1042 	struct pktcdvd_device *pd = pkt->pd;
1043 	BUG_ON(!pd);
1044 
1045 	VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
1046 		(unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
1047 
1048 	if (err)
1049 		atomic_inc(&pkt->io_errors);
1050 	if (atomic_dec_and_test(&pkt->io_wait)) {
1051 		atomic_inc(&pkt->run_sm);
1052 		wake_up(&pd->wqueue);
1053 	}
1054 	pkt_bio_finished(pd);
1055 }
1056 
1057 static void pkt_end_io_packet_write(struct bio *bio, int err)
1058 {
1059 	struct packet_data *pkt = bio->bi_private;
1060 	struct pktcdvd_device *pd = pkt->pd;
1061 	BUG_ON(!pd);
1062 
1063 	VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1064 
1065 	pd->stats.pkt_ended++;
1066 
1067 	pkt_bio_finished(pd);
1068 	atomic_dec(&pkt->io_wait);
1069 	atomic_inc(&pkt->run_sm);
1070 	wake_up(&pd->wqueue);
1071 }
1072 
1073 /*
1074  * Schedule reads for the holes in a packet
1075  */
1076 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1077 {
1078 	int frames_read = 0;
1079 	struct bio *bio;
1080 	int f;
1081 	char written[PACKET_MAX_SIZE];
1082 
1083 	BUG_ON(bio_list_empty(&pkt->orig_bios));
1084 
1085 	atomic_set(&pkt->io_wait, 0);
1086 	atomic_set(&pkt->io_errors, 0);
1087 
1088 	/*
1089 	 * Figure out which frames we need to read before we can write.
1090 	 */
1091 	memset(written, 0, sizeof(written));
1092 	spin_lock(&pkt->lock);
1093 	bio_list_for_each(bio, &pkt->orig_bios) {
1094 		int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1095 		int num_frames = bio->bi_size / CD_FRAMESIZE;
1096 		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1097 		BUG_ON(first_frame < 0);
1098 		BUG_ON(first_frame + num_frames > pkt->frames);
1099 		for (f = first_frame; f < first_frame + num_frames; f++)
1100 			written[f] = 1;
1101 	}
1102 	spin_unlock(&pkt->lock);
1103 
1104 	if (pkt->cache_valid) {
1105 		VPRINTK("pkt_gather_data: zone %llx cached\n",
1106 			(unsigned long long)pkt->sector);
1107 		goto out_account;
1108 	}
1109 
1110 	/*
1111 	 * Schedule reads for missing parts of the packet.
1112 	 */
1113 	for (f = 0; f < pkt->frames; f++) {
1114 		struct bio_vec *vec;
1115 
1116 		int p, offset;
1117 		if (written[f])
1118 			continue;
1119 		bio = pkt->r_bios[f];
1120 		vec = bio->bi_io_vec;
1121 		bio_init(bio);
1122 		bio->bi_max_vecs = 1;
1123 		bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1124 		bio->bi_bdev = pd->bdev;
1125 		bio->bi_end_io = pkt_end_io_read;
1126 		bio->bi_private = pkt;
1127 		bio->bi_io_vec = vec;
1128 		bio->bi_destructor = pkt_bio_destructor;
1129 
1130 		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1131 		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1132 		VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1133 			f, pkt->pages[p], offset);
1134 		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1135 			BUG();
1136 
1137 		atomic_inc(&pkt->io_wait);
1138 		bio->bi_rw = READ;
1139 		pkt_queue_bio(pd, bio);
1140 		frames_read++;
1141 	}
1142 
1143 out_account:
1144 	VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1145 		frames_read, (unsigned long long)pkt->sector);
1146 	pd->stats.pkt_started++;
1147 	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1148 }
1149 
1150 /*
1151  * Find a packet matching zone, or the least recently used packet if
1152  * there is no match.
1153  */
1154 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1155 {
1156 	struct packet_data *pkt;
1157 
1158 	list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1159 		if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1160 			list_del_init(&pkt->list);
1161 			if (pkt->sector != zone)
1162 				pkt->cache_valid = 0;
1163 			return pkt;
1164 		}
1165 	}
1166 	BUG();
1167 	return NULL;
1168 }
1169 
1170 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1171 {
1172 	if (pkt->cache_valid) {
1173 		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1174 	} else {
1175 		list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1176 	}
1177 }
1178 
1179 /*
1180  * recover a failed write, query for relocation if possible
1181  *
1182  * returns 1 if recovery is possible, or 0 if not
1183  *
1184  */
1185 static int pkt_start_recovery(struct packet_data *pkt)
1186 {
1187 	/*
1188 	 * FIXME. We need help from the file system to implement
1189 	 * recovery handling.
1190 	 */
1191 	return 0;
1192 #if 0
1193 	struct request *rq = pkt->rq;
1194 	struct pktcdvd_device *pd = rq->rq_disk->private_data;
1195 	struct block_device *pkt_bdev;
1196 	struct super_block *sb = NULL;
1197 	unsigned long old_block, new_block;
1198 	sector_t new_sector;
1199 
1200 	pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1201 	if (pkt_bdev) {
1202 		sb = get_super(pkt_bdev);
1203 		bdput(pkt_bdev);
1204 	}
1205 
1206 	if (!sb)
1207 		return 0;
1208 
1209 	if (!sb->s_op || !sb->s_op->relocate_blocks)
1210 		goto out;
1211 
1212 	old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1213 	if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1214 		goto out;
1215 
1216 	new_sector = new_block * (CD_FRAMESIZE >> 9);
1217 	pkt->sector = new_sector;
1218 
1219 	pkt->bio->bi_sector = new_sector;
1220 	pkt->bio->bi_next = NULL;
1221 	pkt->bio->bi_flags = 1 << BIO_UPTODATE;
1222 	pkt->bio->bi_idx = 0;
1223 
1224 	BUG_ON(pkt->bio->bi_rw != REQ_WRITE);
1225 	BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
1226 	BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
1227 	BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
1228 	BUG_ON(pkt->bio->bi_private != pkt);
1229 
1230 	drop_super(sb);
1231 	return 1;
1232 
1233 out:
1234 	drop_super(sb);
1235 	return 0;
1236 #endif
1237 }
1238 
1239 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1240 {
1241 #if PACKET_DEBUG > 1
1242 	static const char *state_name[] = {
1243 		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1244 	};
1245 	enum packet_data_state old_state = pkt->state;
1246 	VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1247 		state_name[old_state], state_name[state]);
1248 #endif
1249 	pkt->state = state;
1250 }
1251 
1252 /*
1253  * Scan the work queue to see if we can start a new packet.
1254  * returns non-zero if any work was done.
1255  */
1256 static int pkt_handle_queue(struct pktcdvd_device *pd)
1257 {
1258 	struct packet_data *pkt, *p;
1259 	struct bio *bio = NULL;
1260 	sector_t zone = 0; /* Suppress gcc warning */
1261 	struct pkt_rb_node *node, *first_node;
1262 	struct rb_node *n;
1263 	int wakeup;
1264 
1265 	VPRINTK("handle_queue\n");
1266 
1267 	atomic_set(&pd->scan_queue, 0);
1268 
1269 	if (list_empty(&pd->cdrw.pkt_free_list)) {
1270 		VPRINTK("handle_queue: no pkt\n");
1271 		return 0;
1272 	}
1273 
1274 	/*
1275 	 * Try to find a zone we are not already working on.
1276 	 */
1277 	spin_lock(&pd->lock);
1278 	first_node = pkt_rbtree_find(pd, pd->current_sector);
1279 	if (!first_node) {
1280 		n = rb_first(&pd->bio_queue);
1281 		if (n)
1282 			first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1283 	}
1284 	node = first_node;
1285 	while (node) {
1286 		bio = node->bio;
1287 		zone = ZONE(bio->bi_sector, pd);
1288 		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1289 			if (p->sector == zone) {
1290 				bio = NULL;
1291 				goto try_next_bio;
1292 			}
1293 		}
1294 		break;
1295 try_next_bio:
1296 		node = pkt_rbtree_next(node);
1297 		if (!node) {
1298 			n = rb_first(&pd->bio_queue);
1299 			if (n)
1300 				node = rb_entry(n, struct pkt_rb_node, rb_node);
1301 		}
1302 		if (node == first_node)
1303 			node = NULL;
1304 	}
1305 	spin_unlock(&pd->lock);
1306 	if (!bio) {
1307 		VPRINTK("handle_queue: no bio\n");
1308 		return 0;
1309 	}
1310 
1311 	pkt = pkt_get_packet_data(pd, zone);
1312 
1313 	pd->current_sector = zone + pd->settings.size;
1314 	pkt->sector = zone;
1315 	BUG_ON(pkt->frames != pd->settings.size >> 2);
1316 	pkt->write_size = 0;
1317 
1318 	/*
1319 	 * Scan work queue for bios in the same zone and link them
1320 	 * to this packet.
1321 	 */
1322 	spin_lock(&pd->lock);
1323 	VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1324 	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1325 		bio = node->bio;
1326 		VPRINTK("pkt_handle_queue: found zone=%llx\n",
1327 			(unsigned long long)ZONE(bio->bi_sector, pd));
1328 		if (ZONE(bio->bi_sector, pd) != zone)
1329 			break;
1330 		pkt_rbtree_erase(pd, node);
1331 		spin_lock(&pkt->lock);
1332 		bio_list_add(&pkt->orig_bios, bio);
1333 		pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1334 		spin_unlock(&pkt->lock);
1335 	}
1336 	/* check write congestion marks, and if bio_queue_size is
1337 	   below, wake up any waiters */
1338 	wakeup = (pd->write_congestion_on > 0
1339 	 		&& pd->bio_queue_size <= pd->write_congestion_off);
1340 	spin_unlock(&pd->lock);
1341 	if (wakeup) {
1342 		clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1343 					BLK_RW_ASYNC);
1344 	}
1345 
1346 	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1347 	pkt_set_state(pkt, PACKET_WAITING_STATE);
1348 	atomic_set(&pkt->run_sm, 1);
1349 
1350 	spin_lock(&pd->cdrw.active_list_lock);
1351 	list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1352 	spin_unlock(&pd->cdrw.active_list_lock);
1353 
1354 	return 1;
1355 }
1356 
1357 /*
1358  * Assemble a bio to write one packet and queue the bio for processing
1359  * by the underlying block device.
1360  */
1361 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1362 {
1363 	struct bio *bio;
1364 	int f;
1365 	int frames_write;
1366 	struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1367 
1368 	for (f = 0; f < pkt->frames; f++) {
1369 		bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1370 		bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1371 	}
1372 
1373 	/*
1374 	 * Fill-in bvec with data from orig_bios.
1375 	 */
1376 	frames_write = 0;
1377 	spin_lock(&pkt->lock);
1378 	bio_list_for_each(bio, &pkt->orig_bios) {
1379 		int segment = bio->bi_idx;
1380 		int src_offs = 0;
1381 		int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1382 		int num_frames = bio->bi_size / CD_FRAMESIZE;
1383 		BUG_ON(first_frame < 0);
1384 		BUG_ON(first_frame + num_frames > pkt->frames);
1385 		for (f = first_frame; f < first_frame + num_frames; f++) {
1386 			struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1387 
1388 			while (src_offs >= src_bvl->bv_len) {
1389 				src_offs -= src_bvl->bv_len;
1390 				segment++;
1391 				BUG_ON(segment >= bio->bi_vcnt);
1392 				src_bvl = bio_iovec_idx(bio, segment);
1393 			}
1394 
1395 			if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1396 				bvec[f].bv_page = src_bvl->bv_page;
1397 				bvec[f].bv_offset = src_bvl->bv_offset + src_offs;
1398 			} else {
1399 				pkt_copy_bio_data(bio, segment, src_offs,
1400 						  bvec[f].bv_page, bvec[f].bv_offset);
1401 			}
1402 			src_offs += CD_FRAMESIZE;
1403 			frames_write++;
1404 		}
1405 	}
1406 	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1407 	spin_unlock(&pkt->lock);
1408 
1409 	VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1410 		frames_write, (unsigned long long)pkt->sector);
1411 	BUG_ON(frames_write != pkt->write_size);
1412 
1413 	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1414 		pkt_make_local_copy(pkt, bvec);
1415 		pkt->cache_valid = 1;
1416 	} else {
1417 		pkt->cache_valid = 0;
1418 	}
1419 
1420 	/* Start the write request */
1421 	bio_init(pkt->w_bio);
1422 	pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1423 	pkt->w_bio->bi_sector = pkt->sector;
1424 	pkt->w_bio->bi_bdev = pd->bdev;
1425 	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1426 	pkt->w_bio->bi_private = pkt;
1427 	pkt->w_bio->bi_io_vec = bvec;
1428 	pkt->w_bio->bi_destructor = pkt_bio_destructor;
1429 	for (f = 0; f < pkt->frames; f++)
1430 		if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1431 			BUG();
1432 	VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1433 
1434 	atomic_set(&pkt->io_wait, 1);
1435 	pkt->w_bio->bi_rw = WRITE;
1436 	pkt_queue_bio(pd, pkt->w_bio);
1437 }
1438 
1439 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1440 {
1441 	struct bio *bio;
1442 
1443 	if (!uptodate)
1444 		pkt->cache_valid = 0;
1445 
1446 	/* Finish all bios corresponding to this packet */
1447 	while ((bio = bio_list_pop(&pkt->orig_bios)))
1448 		bio_endio(bio, uptodate ? 0 : -EIO);
1449 }
1450 
1451 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1452 {
1453 	int uptodate;
1454 
1455 	VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1456 
1457 	for (;;) {
1458 		switch (pkt->state) {
1459 		case PACKET_WAITING_STATE:
1460 			if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1461 				return;
1462 
1463 			pkt->sleep_time = 0;
1464 			pkt_gather_data(pd, pkt);
1465 			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1466 			break;
1467 
1468 		case PACKET_READ_WAIT_STATE:
1469 			if (atomic_read(&pkt->io_wait) > 0)
1470 				return;
1471 
1472 			if (atomic_read(&pkt->io_errors) > 0) {
1473 				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1474 			} else {
1475 				pkt_start_write(pd, pkt);
1476 			}
1477 			break;
1478 
1479 		case PACKET_WRITE_WAIT_STATE:
1480 			if (atomic_read(&pkt->io_wait) > 0)
1481 				return;
1482 
1483 			if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1484 				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1485 			} else {
1486 				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1487 			}
1488 			break;
1489 
1490 		case PACKET_RECOVERY_STATE:
1491 			if (pkt_start_recovery(pkt)) {
1492 				pkt_start_write(pd, pkt);
1493 			} else {
1494 				VPRINTK("No recovery possible\n");
1495 				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1496 			}
1497 			break;
1498 
1499 		case PACKET_FINISHED_STATE:
1500 			uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1501 			pkt_finish_packet(pkt, uptodate);
1502 			return;
1503 
1504 		default:
1505 			BUG();
1506 			break;
1507 		}
1508 	}
1509 }
1510 
1511 static void pkt_handle_packets(struct pktcdvd_device *pd)
1512 {
1513 	struct packet_data *pkt, *next;
1514 
1515 	VPRINTK("pkt_handle_packets\n");
1516 
1517 	/*
1518 	 * Run state machine for active packets
1519 	 */
1520 	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1521 		if (atomic_read(&pkt->run_sm) > 0) {
1522 			atomic_set(&pkt->run_sm, 0);
1523 			pkt_run_state_machine(pd, pkt);
1524 		}
1525 	}
1526 
1527 	/*
1528 	 * Move no longer active packets to the free list
1529 	 */
1530 	spin_lock(&pd->cdrw.active_list_lock);
1531 	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1532 		if (pkt->state == PACKET_FINISHED_STATE) {
1533 			list_del(&pkt->list);
1534 			pkt_put_packet_data(pd, pkt);
1535 			pkt_set_state(pkt, PACKET_IDLE_STATE);
1536 			atomic_set(&pd->scan_queue, 1);
1537 		}
1538 	}
1539 	spin_unlock(&pd->cdrw.active_list_lock);
1540 }
1541 
1542 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1543 {
1544 	struct packet_data *pkt;
1545 	int i;
1546 
1547 	for (i = 0; i < PACKET_NUM_STATES; i++)
1548 		states[i] = 0;
1549 
1550 	spin_lock(&pd->cdrw.active_list_lock);
1551 	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1552 		states[pkt->state]++;
1553 	}
1554 	spin_unlock(&pd->cdrw.active_list_lock);
1555 }
1556 
1557 /*
1558  * kcdrwd is woken up when writes have been queued for one of our
1559  * registered devices
1560  */
1561 static int kcdrwd(void *foobar)
1562 {
1563 	struct pktcdvd_device *pd = foobar;
1564 	struct packet_data *pkt;
1565 	long min_sleep_time, residue;
1566 
1567 	set_user_nice(current, -20);
1568 	set_freezable();
1569 
1570 	for (;;) {
1571 		DECLARE_WAITQUEUE(wait, current);
1572 
1573 		/*
1574 		 * Wait until there is something to do
1575 		 */
1576 		add_wait_queue(&pd->wqueue, &wait);
1577 		for (;;) {
1578 			set_current_state(TASK_INTERRUPTIBLE);
1579 
1580 			/* Check if we need to run pkt_handle_queue */
1581 			if (atomic_read(&pd->scan_queue) > 0)
1582 				goto work_to_do;
1583 
1584 			/* Check if we need to run the state machine for some packet */
1585 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1586 				if (atomic_read(&pkt->run_sm) > 0)
1587 					goto work_to_do;
1588 			}
1589 
1590 			/* Check if we need to process the iosched queues */
1591 			if (atomic_read(&pd->iosched.attention) != 0)
1592 				goto work_to_do;
1593 
1594 			/* Otherwise, go to sleep */
1595 			if (PACKET_DEBUG > 1) {
1596 				int states[PACKET_NUM_STATES];
1597 				pkt_count_states(pd, states);
1598 				VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1599 					states[0], states[1], states[2], states[3],
1600 					states[4], states[5]);
1601 			}
1602 
1603 			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1604 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1605 				if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1606 					min_sleep_time = pkt->sleep_time;
1607 			}
1608 
1609 			generic_unplug_device(bdev_get_queue(pd->bdev));
1610 
1611 			VPRINTK("kcdrwd: sleeping\n");
1612 			residue = schedule_timeout(min_sleep_time);
1613 			VPRINTK("kcdrwd: wake up\n");
1614 
1615 			/* make swsusp happy with our thread */
1616 			try_to_freeze();
1617 
1618 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1619 				if (!pkt->sleep_time)
1620 					continue;
1621 				pkt->sleep_time -= min_sleep_time - residue;
1622 				if (pkt->sleep_time <= 0) {
1623 					pkt->sleep_time = 0;
1624 					atomic_inc(&pkt->run_sm);
1625 				}
1626 			}
1627 
1628 			if (kthread_should_stop())
1629 				break;
1630 		}
1631 work_to_do:
1632 		set_current_state(TASK_RUNNING);
1633 		remove_wait_queue(&pd->wqueue, &wait);
1634 
1635 		if (kthread_should_stop())
1636 			break;
1637 
1638 		/*
1639 		 * if pkt_handle_queue returns true, we can queue
1640 		 * another request.
1641 		 */
1642 		while (pkt_handle_queue(pd))
1643 			;
1644 
1645 		/*
1646 		 * Handle packet state machine
1647 		 */
1648 		pkt_handle_packets(pd);
1649 
1650 		/*
1651 		 * Handle iosched queues
1652 		 */
1653 		pkt_iosched_process_queue(pd);
1654 	}
1655 
1656 	return 0;
1657 }
1658 
1659 static void pkt_print_settings(struct pktcdvd_device *pd)
1660 {
1661 	printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1662 	printk("%u blocks, ", pd->settings.size >> 2);
1663 	printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1664 }
1665 
1666 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1667 {
1668 	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1669 
1670 	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1671 	cgc->cmd[2] = page_code | (page_control << 6);
1672 	cgc->cmd[7] = cgc->buflen >> 8;
1673 	cgc->cmd[8] = cgc->buflen & 0xff;
1674 	cgc->data_direction = CGC_DATA_READ;
1675 	return pkt_generic_packet(pd, cgc);
1676 }
1677 
1678 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1679 {
1680 	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1681 	memset(cgc->buffer, 0, 2);
1682 	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1683 	cgc->cmd[1] = 0x10;		/* PF */
1684 	cgc->cmd[7] = cgc->buflen >> 8;
1685 	cgc->cmd[8] = cgc->buflen & 0xff;
1686 	cgc->data_direction = CGC_DATA_WRITE;
1687 	return pkt_generic_packet(pd, cgc);
1688 }
1689 
1690 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1691 {
1692 	struct packet_command cgc;
1693 	int ret;
1694 
1695 	/* set up command and get the disc info */
1696 	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1697 	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1698 	cgc.cmd[8] = cgc.buflen = 2;
1699 	cgc.quiet = 1;
1700 
1701 	if ((ret = pkt_generic_packet(pd, &cgc)))
1702 		return ret;
1703 
1704 	/* not all drives have the same disc_info length, so requeue
1705 	 * packet with the length the drive tells us it can supply
1706 	 */
1707 	cgc.buflen = be16_to_cpu(di->disc_information_length) +
1708 		     sizeof(di->disc_information_length);
1709 
1710 	if (cgc.buflen > sizeof(disc_information))
1711 		cgc.buflen = sizeof(disc_information);
1712 
1713 	cgc.cmd[8] = cgc.buflen;
1714 	return pkt_generic_packet(pd, &cgc);
1715 }
1716 
1717 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1718 {
1719 	struct packet_command cgc;
1720 	int ret;
1721 
1722 	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1723 	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1724 	cgc.cmd[1] = type & 3;
1725 	cgc.cmd[4] = (track & 0xff00) >> 8;
1726 	cgc.cmd[5] = track & 0xff;
1727 	cgc.cmd[8] = 8;
1728 	cgc.quiet = 1;
1729 
1730 	if ((ret = pkt_generic_packet(pd, &cgc)))
1731 		return ret;
1732 
1733 	cgc.buflen = be16_to_cpu(ti->track_information_length) +
1734 		     sizeof(ti->track_information_length);
1735 
1736 	if (cgc.buflen > sizeof(track_information))
1737 		cgc.buflen = sizeof(track_information);
1738 
1739 	cgc.cmd[8] = cgc.buflen;
1740 	return pkt_generic_packet(pd, &cgc);
1741 }
1742 
1743 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1744 						long *last_written)
1745 {
1746 	disc_information di;
1747 	track_information ti;
1748 	__u32 last_track;
1749 	int ret = -1;
1750 
1751 	if ((ret = pkt_get_disc_info(pd, &di)))
1752 		return ret;
1753 
1754 	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1755 	if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1756 		return ret;
1757 
1758 	/* if this track is blank, try the previous. */
1759 	if (ti.blank) {
1760 		last_track--;
1761 		if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1762 			return ret;
1763 	}
1764 
1765 	/* if last recorded field is valid, return it. */
1766 	if (ti.lra_v) {
1767 		*last_written = be32_to_cpu(ti.last_rec_address);
1768 	} else {
1769 		/* make it up instead */
1770 		*last_written = be32_to_cpu(ti.track_start) +
1771 				be32_to_cpu(ti.track_size);
1772 		if (ti.free_blocks)
1773 			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1774 	}
1775 	return 0;
1776 }
1777 
1778 /*
1779  * write mode select package based on pd->settings
1780  */
1781 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1782 {
1783 	struct packet_command cgc;
1784 	struct request_sense sense;
1785 	write_param_page *wp;
1786 	char buffer[128];
1787 	int ret, size;
1788 
1789 	/* doesn't apply to DVD+RW or DVD-RAM */
1790 	if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1791 		return 0;
1792 
1793 	memset(buffer, 0, sizeof(buffer));
1794 	init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1795 	cgc.sense = &sense;
1796 	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1797 		pkt_dump_sense(&cgc);
1798 		return ret;
1799 	}
1800 
1801 	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1802 	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1803 	if (size > sizeof(buffer))
1804 		size = sizeof(buffer);
1805 
1806 	/*
1807 	 * now get it all
1808 	 */
1809 	init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1810 	cgc.sense = &sense;
1811 	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1812 		pkt_dump_sense(&cgc);
1813 		return ret;
1814 	}
1815 
1816 	/*
1817 	 * write page is offset header + block descriptor length
1818 	 */
1819 	wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1820 
1821 	wp->fp = pd->settings.fp;
1822 	wp->track_mode = pd->settings.track_mode;
1823 	wp->write_type = pd->settings.write_type;
1824 	wp->data_block_type = pd->settings.block_mode;
1825 
1826 	wp->multi_session = 0;
1827 
1828 #ifdef PACKET_USE_LS
1829 	wp->link_size = 7;
1830 	wp->ls_v = 1;
1831 #endif
1832 
1833 	if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1834 		wp->session_format = 0;
1835 		wp->subhdr2 = 0x20;
1836 	} else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1837 		wp->session_format = 0x20;
1838 		wp->subhdr2 = 8;
1839 #if 0
1840 		wp->mcn[0] = 0x80;
1841 		memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1842 #endif
1843 	} else {
1844 		/*
1845 		 * paranoia
1846 		 */
1847 		printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1848 		return 1;
1849 	}
1850 	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1851 
1852 	cgc.buflen = cgc.cmd[8] = size;
1853 	if ((ret = pkt_mode_select(pd, &cgc))) {
1854 		pkt_dump_sense(&cgc);
1855 		return ret;
1856 	}
1857 
1858 	pkt_print_settings(pd);
1859 	return 0;
1860 }
1861 
1862 /*
1863  * 1 -- we can write to this track, 0 -- we can't
1864  */
1865 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1866 {
1867 	switch (pd->mmc3_profile) {
1868 		case 0x1a: /* DVD+RW */
1869 		case 0x12: /* DVD-RAM */
1870 			/* The track is always writable on DVD+RW/DVD-RAM */
1871 			return 1;
1872 		default:
1873 			break;
1874 	}
1875 
1876 	if (!ti->packet || !ti->fp)
1877 		return 0;
1878 
1879 	/*
1880 	 * "good" settings as per Mt Fuji.
1881 	 */
1882 	if (ti->rt == 0 && ti->blank == 0)
1883 		return 1;
1884 
1885 	if (ti->rt == 0 && ti->blank == 1)
1886 		return 1;
1887 
1888 	if (ti->rt == 1 && ti->blank == 0)
1889 		return 1;
1890 
1891 	printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1892 	return 0;
1893 }
1894 
1895 /*
1896  * 1 -- we can write to this disc, 0 -- we can't
1897  */
1898 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1899 {
1900 	switch (pd->mmc3_profile) {
1901 		case 0x0a: /* CD-RW */
1902 		case 0xffff: /* MMC3 not supported */
1903 			break;
1904 		case 0x1a: /* DVD+RW */
1905 		case 0x13: /* DVD-RW */
1906 		case 0x12: /* DVD-RAM */
1907 			return 1;
1908 		default:
1909 			VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1910 			return 0;
1911 	}
1912 
1913 	/*
1914 	 * for disc type 0xff we should probably reserve a new track.
1915 	 * but i'm not sure, should we leave this to user apps? probably.
1916 	 */
1917 	if (di->disc_type == 0xff) {
1918 		printk(DRIVER_NAME": Unknown disc. No track?\n");
1919 		return 0;
1920 	}
1921 
1922 	if (di->disc_type != 0x20 && di->disc_type != 0) {
1923 		printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1924 		return 0;
1925 	}
1926 
1927 	if (di->erasable == 0) {
1928 		printk(DRIVER_NAME": Disc not erasable\n");
1929 		return 0;
1930 	}
1931 
1932 	if (di->border_status == PACKET_SESSION_RESERVED) {
1933 		printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1934 		return 0;
1935 	}
1936 
1937 	return 1;
1938 }
1939 
1940 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1941 {
1942 	struct packet_command cgc;
1943 	unsigned char buf[12];
1944 	disc_information di;
1945 	track_information ti;
1946 	int ret, track;
1947 
1948 	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1949 	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1950 	cgc.cmd[8] = 8;
1951 	ret = pkt_generic_packet(pd, &cgc);
1952 	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1953 
1954 	memset(&di, 0, sizeof(disc_information));
1955 	memset(&ti, 0, sizeof(track_information));
1956 
1957 	if ((ret = pkt_get_disc_info(pd, &di))) {
1958 		printk("failed get_disc\n");
1959 		return ret;
1960 	}
1961 
1962 	if (!pkt_writable_disc(pd, &di))
1963 		return -EROFS;
1964 
1965 	pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1966 
1967 	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1968 	if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1969 		printk(DRIVER_NAME": failed get_track\n");
1970 		return ret;
1971 	}
1972 
1973 	if (!pkt_writable_track(pd, &ti)) {
1974 		printk(DRIVER_NAME": can't write to this track\n");
1975 		return -EROFS;
1976 	}
1977 
1978 	/*
1979 	 * we keep packet size in 512 byte units, makes it easier to
1980 	 * deal with request calculations.
1981 	 */
1982 	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1983 	if (pd->settings.size == 0) {
1984 		printk(DRIVER_NAME": detected zero packet size!\n");
1985 		return -ENXIO;
1986 	}
1987 	if (pd->settings.size > PACKET_MAX_SECTORS) {
1988 		printk(DRIVER_NAME": packet size is too big\n");
1989 		return -EROFS;
1990 	}
1991 	pd->settings.fp = ti.fp;
1992 	pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1993 
1994 	if (ti.nwa_v) {
1995 		pd->nwa = be32_to_cpu(ti.next_writable);
1996 		set_bit(PACKET_NWA_VALID, &pd->flags);
1997 	}
1998 
1999 	/*
2000 	 * in theory we could use lra on -RW media as well and just zero
2001 	 * blocks that haven't been written yet, but in practice that
2002 	 * is just a no-go. we'll use that for -R, naturally.
2003 	 */
2004 	if (ti.lra_v) {
2005 		pd->lra = be32_to_cpu(ti.last_rec_address);
2006 		set_bit(PACKET_LRA_VALID, &pd->flags);
2007 	} else {
2008 		pd->lra = 0xffffffff;
2009 		set_bit(PACKET_LRA_VALID, &pd->flags);
2010 	}
2011 
2012 	/*
2013 	 * fine for now
2014 	 */
2015 	pd->settings.link_loss = 7;
2016 	pd->settings.write_type = 0;	/* packet */
2017 	pd->settings.track_mode = ti.track_mode;
2018 
2019 	/*
2020 	 * mode1 or mode2 disc
2021 	 */
2022 	switch (ti.data_mode) {
2023 		case PACKET_MODE1:
2024 			pd->settings.block_mode = PACKET_BLOCK_MODE1;
2025 			break;
2026 		case PACKET_MODE2:
2027 			pd->settings.block_mode = PACKET_BLOCK_MODE2;
2028 			break;
2029 		default:
2030 			printk(DRIVER_NAME": unknown data mode\n");
2031 			return -EROFS;
2032 	}
2033 	return 0;
2034 }
2035 
2036 /*
2037  * enable/disable write caching on drive
2038  */
2039 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
2040 						int set)
2041 {
2042 	struct packet_command cgc;
2043 	struct request_sense sense;
2044 	unsigned char buf[64];
2045 	int ret;
2046 
2047 	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
2048 	cgc.sense = &sense;
2049 	cgc.buflen = pd->mode_offset + 12;
2050 
2051 	/*
2052 	 * caching mode page might not be there, so quiet this command
2053 	 */
2054 	cgc.quiet = 1;
2055 
2056 	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
2057 		return ret;
2058 
2059 	buf[pd->mode_offset + 10] |= (!!set << 2);
2060 
2061 	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
2062 	ret = pkt_mode_select(pd, &cgc);
2063 	if (ret) {
2064 		printk(DRIVER_NAME": write caching control failed\n");
2065 		pkt_dump_sense(&cgc);
2066 	} else if (!ret && set)
2067 		printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
2068 	return ret;
2069 }
2070 
2071 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
2072 {
2073 	struct packet_command cgc;
2074 
2075 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2076 	cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
2077 	cgc.cmd[4] = lockflag ? 1 : 0;
2078 	return pkt_generic_packet(pd, &cgc);
2079 }
2080 
2081 /*
2082  * Returns drive maximum write speed
2083  */
2084 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
2085 						unsigned *write_speed)
2086 {
2087 	struct packet_command cgc;
2088 	struct request_sense sense;
2089 	unsigned char buf[256+18];
2090 	unsigned char *cap_buf;
2091 	int ret, offset;
2092 
2093 	cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
2094 	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2095 	cgc.sense = &sense;
2096 
2097 	ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2098 	if (ret) {
2099 		cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2100 			     sizeof(struct mode_page_header);
2101 		ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2102 		if (ret) {
2103 			pkt_dump_sense(&cgc);
2104 			return ret;
2105 		}
2106 	}
2107 
2108 	offset = 20;			    /* Obsoleted field, used by older drives */
2109 	if (cap_buf[1] >= 28)
2110 		offset = 28;		    /* Current write speed selected */
2111 	if (cap_buf[1] >= 30) {
2112 		/* If the drive reports at least one "Logical Unit Write
2113 		 * Speed Performance Descriptor Block", use the information
2114 		 * in the first block. (contains the highest speed)
2115 		 */
2116 		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2117 		if (num_spdb > 0)
2118 			offset = 34;
2119 	}
2120 
2121 	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2122 	return 0;
2123 }
2124 
2125 /* These tables from cdrecord - I don't have orange book */
2126 /* standard speed CD-RW (1-4x) */
2127 static char clv_to_speed[16] = {
2128 	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2129 	   0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2130 };
2131 /* high speed CD-RW (-10x) */
2132 static char hs_clv_to_speed[16] = {
2133 	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2134 	   0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2135 };
2136 /* ultra high speed CD-RW */
2137 static char us_clv_to_speed[16] = {
2138 	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2139 	   0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2140 };
2141 
2142 /*
2143  * reads the maximum media speed from ATIP
2144  */
2145 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2146 						unsigned *speed)
2147 {
2148 	struct packet_command cgc;
2149 	struct request_sense sense;
2150 	unsigned char buf[64];
2151 	unsigned int size, st, sp;
2152 	int ret;
2153 
2154 	init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2155 	cgc.sense = &sense;
2156 	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2157 	cgc.cmd[1] = 2;
2158 	cgc.cmd[2] = 4; /* READ ATIP */
2159 	cgc.cmd[8] = 2;
2160 	ret = pkt_generic_packet(pd, &cgc);
2161 	if (ret) {
2162 		pkt_dump_sense(&cgc);
2163 		return ret;
2164 	}
2165 	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2166 	if (size > sizeof(buf))
2167 		size = sizeof(buf);
2168 
2169 	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2170 	cgc.sense = &sense;
2171 	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2172 	cgc.cmd[1] = 2;
2173 	cgc.cmd[2] = 4;
2174 	cgc.cmd[8] = size;
2175 	ret = pkt_generic_packet(pd, &cgc);
2176 	if (ret) {
2177 		pkt_dump_sense(&cgc);
2178 		return ret;
2179 	}
2180 
2181 	if (!(buf[6] & 0x40)) {
2182 		printk(DRIVER_NAME": Disc type is not CD-RW\n");
2183 		return 1;
2184 	}
2185 	if (!(buf[6] & 0x4)) {
2186 		printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2187 		return 1;
2188 	}
2189 
2190 	st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2191 
2192 	sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2193 
2194 	/* Info from cdrecord */
2195 	switch (st) {
2196 		case 0: /* standard speed */
2197 			*speed = clv_to_speed[sp];
2198 			break;
2199 		case 1: /* high speed */
2200 			*speed = hs_clv_to_speed[sp];
2201 			break;
2202 		case 2: /* ultra high speed */
2203 			*speed = us_clv_to_speed[sp];
2204 			break;
2205 		default:
2206 			printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2207 			return 1;
2208 	}
2209 	if (*speed) {
2210 		printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2211 		return 0;
2212 	} else {
2213 		printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2214 		return 1;
2215 	}
2216 }
2217 
2218 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2219 {
2220 	struct packet_command cgc;
2221 	struct request_sense sense;
2222 	int ret;
2223 
2224 	VPRINTK(DRIVER_NAME": Performing OPC\n");
2225 
2226 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2227 	cgc.sense = &sense;
2228 	cgc.timeout = 60*HZ;
2229 	cgc.cmd[0] = GPCMD_SEND_OPC;
2230 	cgc.cmd[1] = 1;
2231 	if ((ret = pkt_generic_packet(pd, &cgc)))
2232 		pkt_dump_sense(&cgc);
2233 	return ret;
2234 }
2235 
2236 static int pkt_open_write(struct pktcdvd_device *pd)
2237 {
2238 	int ret;
2239 	unsigned int write_speed, media_write_speed, read_speed;
2240 
2241 	if ((ret = pkt_probe_settings(pd))) {
2242 		VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2243 		return ret;
2244 	}
2245 
2246 	if ((ret = pkt_set_write_settings(pd))) {
2247 		DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2248 		return -EIO;
2249 	}
2250 
2251 	pkt_write_caching(pd, USE_WCACHING);
2252 
2253 	if ((ret = pkt_get_max_speed(pd, &write_speed)))
2254 		write_speed = 16 * 177;
2255 	switch (pd->mmc3_profile) {
2256 		case 0x13: /* DVD-RW */
2257 		case 0x1a: /* DVD+RW */
2258 		case 0x12: /* DVD-RAM */
2259 			DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2260 			break;
2261 		default:
2262 			if ((ret = pkt_media_speed(pd, &media_write_speed)))
2263 				media_write_speed = 16;
2264 			write_speed = min(write_speed, media_write_speed * 177);
2265 			DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2266 			break;
2267 	}
2268 	read_speed = write_speed;
2269 
2270 	if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2271 		DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2272 		return -EIO;
2273 	}
2274 	pd->write_speed = write_speed;
2275 	pd->read_speed = read_speed;
2276 
2277 	if ((ret = pkt_perform_opc(pd))) {
2278 		DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2279 	}
2280 
2281 	return 0;
2282 }
2283 
2284 /*
2285  * called at open time.
2286  */
2287 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2288 {
2289 	int ret;
2290 	long lba;
2291 	struct request_queue *q;
2292 
2293 	/*
2294 	 * We need to re-open the cdrom device without O_NONBLOCK to be able
2295 	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2296 	 * so bdget() can't fail.
2297 	 */
2298 	bdget(pd->bdev->bd_dev);
2299 	if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2300 		goto out;
2301 
2302 	if ((ret = pkt_get_last_written(pd, &lba))) {
2303 		printk(DRIVER_NAME": pkt_get_last_written failed\n");
2304 		goto out_putdev;
2305 	}
2306 
2307 	set_capacity(pd->disk, lba << 2);
2308 	set_capacity(pd->bdev->bd_disk, lba << 2);
2309 	bd_set_size(pd->bdev, (loff_t)lba << 11);
2310 
2311 	q = bdev_get_queue(pd->bdev);
2312 	if (write) {
2313 		if ((ret = pkt_open_write(pd)))
2314 			goto out_putdev;
2315 		/*
2316 		 * Some CDRW drives can not handle writes larger than one packet,
2317 		 * even if the size is a multiple of the packet size.
2318 		 */
2319 		spin_lock_irq(q->queue_lock);
2320 		blk_queue_max_hw_sectors(q, pd->settings.size);
2321 		spin_unlock_irq(q->queue_lock);
2322 		set_bit(PACKET_WRITABLE, &pd->flags);
2323 	} else {
2324 		pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2325 		clear_bit(PACKET_WRITABLE, &pd->flags);
2326 	}
2327 
2328 	if ((ret = pkt_set_segment_merging(pd, q)))
2329 		goto out_putdev;
2330 
2331 	if (write) {
2332 		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2333 			printk(DRIVER_NAME": not enough memory for buffers\n");
2334 			ret = -ENOMEM;
2335 			goto out_putdev;
2336 		}
2337 		printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2338 	}
2339 
2340 	return 0;
2341 
2342 out_putdev:
2343 	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2344 out:
2345 	return ret;
2346 }
2347 
2348 /*
2349  * called when the device is closed. makes sure that the device flushes
2350  * the internal cache before we close.
2351  */
2352 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2353 {
2354 	if (flush && pkt_flush_cache(pd))
2355 		DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2356 
2357 	pkt_lock_door(pd, 0);
2358 
2359 	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2360 	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2361 
2362 	pkt_shrink_pktlist(pd);
2363 }
2364 
2365 static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2366 {
2367 	if (dev_minor >= MAX_WRITERS)
2368 		return NULL;
2369 	return pkt_devs[dev_minor];
2370 }
2371 
2372 static int pkt_open(struct block_device *bdev, fmode_t mode)
2373 {
2374 	struct pktcdvd_device *pd = NULL;
2375 	int ret;
2376 
2377 	VPRINTK(DRIVER_NAME": entering open\n");
2378 
2379 	mutex_lock(&pktcdvd_mutex);
2380 	mutex_lock(&ctl_mutex);
2381 	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2382 	if (!pd) {
2383 		ret = -ENODEV;
2384 		goto out;
2385 	}
2386 	BUG_ON(pd->refcnt < 0);
2387 
2388 	pd->refcnt++;
2389 	if (pd->refcnt > 1) {
2390 		if ((mode & FMODE_WRITE) &&
2391 		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
2392 			ret = -EBUSY;
2393 			goto out_dec;
2394 		}
2395 	} else {
2396 		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2397 		if (ret)
2398 			goto out_dec;
2399 		/*
2400 		 * needed here as well, since ext2 (among others) may change
2401 		 * the blocksize at mount time
2402 		 */
2403 		set_blocksize(bdev, CD_FRAMESIZE);
2404 	}
2405 
2406 	mutex_unlock(&ctl_mutex);
2407 	mutex_unlock(&pktcdvd_mutex);
2408 	return 0;
2409 
2410 out_dec:
2411 	pd->refcnt--;
2412 out:
2413 	VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2414 	mutex_unlock(&ctl_mutex);
2415 	mutex_unlock(&pktcdvd_mutex);
2416 	return ret;
2417 }
2418 
2419 static int pkt_close(struct gendisk *disk, fmode_t mode)
2420 {
2421 	struct pktcdvd_device *pd = disk->private_data;
2422 	int ret = 0;
2423 
2424 	mutex_lock(&pktcdvd_mutex);
2425 	mutex_lock(&ctl_mutex);
2426 	pd->refcnt--;
2427 	BUG_ON(pd->refcnt < 0);
2428 	if (pd->refcnt == 0) {
2429 		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2430 		pkt_release_dev(pd, flush);
2431 	}
2432 	mutex_unlock(&ctl_mutex);
2433 	mutex_unlock(&pktcdvd_mutex);
2434 	return ret;
2435 }
2436 
2437 
2438 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2439 {
2440 	struct packet_stacked_data *psd = bio->bi_private;
2441 	struct pktcdvd_device *pd = psd->pd;
2442 
2443 	bio_put(bio);
2444 	bio_endio(psd->bio, err);
2445 	mempool_free(psd, psd_pool);
2446 	pkt_bio_finished(pd);
2447 }
2448 
2449 static int pkt_make_request(struct request_queue *q, struct bio *bio)
2450 {
2451 	struct pktcdvd_device *pd;
2452 	char b[BDEVNAME_SIZE];
2453 	sector_t zone;
2454 	struct packet_data *pkt;
2455 	int was_empty, blocked_bio;
2456 	struct pkt_rb_node *node;
2457 
2458 	pd = q->queuedata;
2459 	if (!pd) {
2460 		printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2461 		goto end_io;
2462 	}
2463 
2464 	/*
2465 	 * Clone READ bios so we can have our own bi_end_io callback.
2466 	 */
2467 	if (bio_data_dir(bio) == READ) {
2468 		struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2469 		struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2470 
2471 		psd->pd = pd;
2472 		psd->bio = bio;
2473 		cloned_bio->bi_bdev = pd->bdev;
2474 		cloned_bio->bi_private = psd;
2475 		cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2476 		pd->stats.secs_r += bio->bi_size >> 9;
2477 		pkt_queue_bio(pd, cloned_bio);
2478 		return 0;
2479 	}
2480 
2481 	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2482 		printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2483 			pd->name, (unsigned long long)bio->bi_sector);
2484 		goto end_io;
2485 	}
2486 
2487 	if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2488 		printk(DRIVER_NAME": wrong bio size\n");
2489 		goto end_io;
2490 	}
2491 
2492 	blk_queue_bounce(q, &bio);
2493 
2494 	zone = ZONE(bio->bi_sector, pd);
2495 	VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2496 		(unsigned long long)bio->bi_sector,
2497 		(unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2498 
2499 	/* Check if we have to split the bio */
2500 	{
2501 		struct bio_pair *bp;
2502 		sector_t last_zone;
2503 		int first_sectors;
2504 
2505 		last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2506 		if (last_zone != zone) {
2507 			BUG_ON(last_zone != zone + pd->settings.size);
2508 			first_sectors = last_zone - bio->bi_sector;
2509 			bp = bio_split(bio, first_sectors);
2510 			BUG_ON(!bp);
2511 			pkt_make_request(q, &bp->bio1);
2512 			pkt_make_request(q, &bp->bio2);
2513 			bio_pair_release(bp);
2514 			return 0;
2515 		}
2516 	}
2517 
2518 	/*
2519 	 * If we find a matching packet in state WAITING or READ_WAIT, we can
2520 	 * just append this bio to that packet.
2521 	 */
2522 	spin_lock(&pd->cdrw.active_list_lock);
2523 	blocked_bio = 0;
2524 	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2525 		if (pkt->sector == zone) {
2526 			spin_lock(&pkt->lock);
2527 			if ((pkt->state == PACKET_WAITING_STATE) ||
2528 			    (pkt->state == PACKET_READ_WAIT_STATE)) {
2529 				bio_list_add(&pkt->orig_bios, bio);
2530 				pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2531 				if ((pkt->write_size >= pkt->frames) &&
2532 				    (pkt->state == PACKET_WAITING_STATE)) {
2533 					atomic_inc(&pkt->run_sm);
2534 					wake_up(&pd->wqueue);
2535 				}
2536 				spin_unlock(&pkt->lock);
2537 				spin_unlock(&pd->cdrw.active_list_lock);
2538 				return 0;
2539 			} else {
2540 				blocked_bio = 1;
2541 			}
2542 			spin_unlock(&pkt->lock);
2543 		}
2544 	}
2545 	spin_unlock(&pd->cdrw.active_list_lock);
2546 
2547  	/*
2548 	 * Test if there is enough room left in the bio work queue
2549 	 * (queue size >= congestion on mark).
2550 	 * If not, wait till the work queue size is below the congestion off mark.
2551 	 */
2552 	spin_lock(&pd->lock);
2553 	if (pd->write_congestion_on > 0
2554 	    && pd->bio_queue_size >= pd->write_congestion_on) {
2555 		set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2556 		do {
2557 			spin_unlock(&pd->lock);
2558 			congestion_wait(BLK_RW_ASYNC, HZ);
2559 			spin_lock(&pd->lock);
2560 		} while(pd->bio_queue_size > pd->write_congestion_off);
2561 	}
2562 	spin_unlock(&pd->lock);
2563 
2564 	/*
2565 	 * No matching packet found. Store the bio in the work queue.
2566 	 */
2567 	node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2568 	node->bio = bio;
2569 	spin_lock(&pd->lock);
2570 	BUG_ON(pd->bio_queue_size < 0);
2571 	was_empty = (pd->bio_queue_size == 0);
2572 	pkt_rbtree_insert(pd, node);
2573 	spin_unlock(&pd->lock);
2574 
2575 	/*
2576 	 * Wake up the worker thread.
2577 	 */
2578 	atomic_set(&pd->scan_queue, 1);
2579 	if (was_empty) {
2580 		/* This wake_up is required for correct operation */
2581 		wake_up(&pd->wqueue);
2582 	} else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2583 		/*
2584 		 * This wake up is not required for correct operation,
2585 		 * but improves performance in some cases.
2586 		 */
2587 		wake_up(&pd->wqueue);
2588 	}
2589 	return 0;
2590 end_io:
2591 	bio_io_error(bio);
2592 	return 0;
2593 }
2594 
2595 
2596 
2597 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2598 			  struct bio_vec *bvec)
2599 {
2600 	struct pktcdvd_device *pd = q->queuedata;
2601 	sector_t zone = ZONE(bmd->bi_sector, pd);
2602 	int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2603 	int remaining = (pd->settings.size << 9) - used;
2604 	int remaining2;
2605 
2606 	/*
2607 	 * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2608 	 * boundary, pkt_make_request() will split the bio.
2609 	 */
2610 	remaining2 = PAGE_SIZE - bmd->bi_size;
2611 	remaining = max(remaining, remaining2);
2612 
2613 	BUG_ON(remaining < 0);
2614 	return remaining;
2615 }
2616 
2617 static void pkt_init_queue(struct pktcdvd_device *pd)
2618 {
2619 	struct request_queue *q = pd->disk->queue;
2620 
2621 	blk_queue_make_request(q, pkt_make_request);
2622 	blk_queue_logical_block_size(q, CD_FRAMESIZE);
2623 	blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2624 	blk_queue_merge_bvec(q, pkt_merge_bvec);
2625 	q->queuedata = pd;
2626 }
2627 
2628 static int pkt_seq_show(struct seq_file *m, void *p)
2629 {
2630 	struct pktcdvd_device *pd = m->private;
2631 	char *msg;
2632 	char bdev_buf[BDEVNAME_SIZE];
2633 	int states[PACKET_NUM_STATES];
2634 
2635 	seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2636 		   bdevname(pd->bdev, bdev_buf));
2637 
2638 	seq_printf(m, "\nSettings:\n");
2639 	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2640 
2641 	if (pd->settings.write_type == 0)
2642 		msg = "Packet";
2643 	else
2644 		msg = "Unknown";
2645 	seq_printf(m, "\twrite type:\t\t%s\n", msg);
2646 
2647 	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2648 	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2649 
2650 	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2651 
2652 	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2653 		msg = "Mode 1";
2654 	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2655 		msg = "Mode 2";
2656 	else
2657 		msg = "Unknown";
2658 	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2659 
2660 	seq_printf(m, "\nStatistics:\n");
2661 	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2662 	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2663 	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2664 	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2665 	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2666 
2667 	seq_printf(m, "\nMisc:\n");
2668 	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2669 	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2670 	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2671 	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2672 	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2673 	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2674 
2675 	seq_printf(m, "\nQueue state:\n");
2676 	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2677 	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2678 	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2679 
2680 	pkt_count_states(pd, states);
2681 	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2682 		   states[0], states[1], states[2], states[3], states[4], states[5]);
2683 
2684 	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2685 			pd->write_congestion_off,
2686 			pd->write_congestion_on);
2687 	return 0;
2688 }
2689 
2690 static int pkt_seq_open(struct inode *inode, struct file *file)
2691 {
2692 	return single_open(file, pkt_seq_show, PDE(inode)->data);
2693 }
2694 
2695 static const struct file_operations pkt_proc_fops = {
2696 	.open	= pkt_seq_open,
2697 	.read	= seq_read,
2698 	.llseek	= seq_lseek,
2699 	.release = single_release
2700 };
2701 
2702 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2703 {
2704 	int i;
2705 	int ret = 0;
2706 	char b[BDEVNAME_SIZE];
2707 	struct block_device *bdev;
2708 
2709 	if (pd->pkt_dev == dev) {
2710 		printk(DRIVER_NAME": Recursive setup not allowed\n");
2711 		return -EBUSY;
2712 	}
2713 	for (i = 0; i < MAX_WRITERS; i++) {
2714 		struct pktcdvd_device *pd2 = pkt_devs[i];
2715 		if (!pd2)
2716 			continue;
2717 		if (pd2->bdev->bd_dev == dev) {
2718 			printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
2719 			return -EBUSY;
2720 		}
2721 		if (pd2->pkt_dev == dev) {
2722 			printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2723 			return -EBUSY;
2724 		}
2725 	}
2726 
2727 	bdev = bdget(dev);
2728 	if (!bdev)
2729 		return -ENOMEM;
2730 	ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2731 	if (ret)
2732 		return ret;
2733 
2734 	/* This is safe, since we have a reference from open(). */
2735 	__module_get(THIS_MODULE);
2736 
2737 	pd->bdev = bdev;
2738 	set_blocksize(bdev, CD_FRAMESIZE);
2739 
2740 	pkt_init_queue(pd);
2741 
2742 	atomic_set(&pd->cdrw.pending_bios, 0);
2743 	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2744 	if (IS_ERR(pd->cdrw.thread)) {
2745 		printk(DRIVER_NAME": can't start kernel thread\n");
2746 		ret = -ENOMEM;
2747 		goto out_mem;
2748 	}
2749 
2750 	proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2751 	DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2752 	return 0;
2753 
2754 out_mem:
2755 	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2756 	/* This is safe: open() is still holding a reference. */
2757 	module_put(THIS_MODULE);
2758 	return ret;
2759 }
2760 
2761 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2762 {
2763 	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2764 	int ret;
2765 
2766 	VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2767 		MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2768 
2769 	mutex_lock(&pktcdvd_mutex);
2770 	switch (cmd) {
2771 	case CDROMEJECT:
2772 		/*
2773 		 * The door gets locked when the device is opened, so we
2774 		 * have to unlock it or else the eject command fails.
2775 		 */
2776 		if (pd->refcnt == 1)
2777 			pkt_lock_door(pd, 0);
2778 		/* fallthru */
2779 	/*
2780 	 * forward selected CDROM ioctls to CD-ROM, for UDF
2781 	 */
2782 	case CDROMMULTISESSION:
2783 	case CDROMREADTOCENTRY:
2784 	case CDROM_LAST_WRITTEN:
2785 	case CDROM_SEND_PACKET:
2786 	case SCSI_IOCTL_SEND_COMMAND:
2787 		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2788 		break;
2789 
2790 	default:
2791 		VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2792 		ret = -ENOTTY;
2793 	}
2794 	mutex_unlock(&pktcdvd_mutex);
2795 
2796 	return ret;
2797 }
2798 
2799 static int pkt_media_changed(struct gendisk *disk)
2800 {
2801 	struct pktcdvd_device *pd = disk->private_data;
2802 	struct gendisk *attached_disk;
2803 
2804 	if (!pd)
2805 		return 0;
2806 	if (!pd->bdev)
2807 		return 0;
2808 	attached_disk = pd->bdev->bd_disk;
2809 	if (!attached_disk)
2810 		return 0;
2811 	return attached_disk->fops->media_changed(attached_disk);
2812 }
2813 
2814 static const struct block_device_operations pktcdvd_ops = {
2815 	.owner =		THIS_MODULE,
2816 	.open =			pkt_open,
2817 	.release =		pkt_close,
2818 	.ioctl =		pkt_ioctl,
2819 	.media_changed =	pkt_media_changed,
2820 };
2821 
2822 static char *pktcdvd_devnode(struct gendisk *gd, mode_t *mode)
2823 {
2824 	return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2825 }
2826 
2827 /*
2828  * Set up mapping from pktcdvd device to CD-ROM device.
2829  */
2830 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2831 {
2832 	int idx;
2833 	int ret = -ENOMEM;
2834 	struct pktcdvd_device *pd;
2835 	struct gendisk *disk;
2836 
2837 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2838 
2839 	for (idx = 0; idx < MAX_WRITERS; idx++)
2840 		if (!pkt_devs[idx])
2841 			break;
2842 	if (idx == MAX_WRITERS) {
2843 		printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2844 		ret = -EBUSY;
2845 		goto out_mutex;
2846 	}
2847 
2848 	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2849 	if (!pd)
2850 		goto out_mutex;
2851 
2852 	pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2853 						  sizeof(struct pkt_rb_node));
2854 	if (!pd->rb_pool)
2855 		goto out_mem;
2856 
2857 	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2858 	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2859 	spin_lock_init(&pd->cdrw.active_list_lock);
2860 
2861 	spin_lock_init(&pd->lock);
2862 	spin_lock_init(&pd->iosched.lock);
2863 	bio_list_init(&pd->iosched.read_queue);
2864 	bio_list_init(&pd->iosched.write_queue);
2865 	sprintf(pd->name, DRIVER_NAME"%d", idx);
2866 	init_waitqueue_head(&pd->wqueue);
2867 	pd->bio_queue = RB_ROOT;
2868 
2869 	pd->write_congestion_on  = write_congestion_on;
2870 	pd->write_congestion_off = write_congestion_off;
2871 
2872 	disk = alloc_disk(1);
2873 	if (!disk)
2874 		goto out_mem;
2875 	pd->disk = disk;
2876 	disk->major = pktdev_major;
2877 	disk->first_minor = idx;
2878 	disk->fops = &pktcdvd_ops;
2879 	disk->flags = GENHD_FL_REMOVABLE;
2880 	strcpy(disk->disk_name, pd->name);
2881 	disk->devnode = pktcdvd_devnode;
2882 	disk->private_data = pd;
2883 	disk->queue = blk_alloc_queue(GFP_KERNEL);
2884 	if (!disk->queue)
2885 		goto out_mem2;
2886 
2887 	pd->pkt_dev = MKDEV(pktdev_major, idx);
2888 	ret = pkt_new_dev(pd, dev);
2889 	if (ret)
2890 		goto out_new_dev;
2891 
2892 	add_disk(disk);
2893 
2894 	pkt_sysfs_dev_new(pd);
2895 	pkt_debugfs_dev_new(pd);
2896 
2897 	pkt_devs[idx] = pd;
2898 	if (pkt_dev)
2899 		*pkt_dev = pd->pkt_dev;
2900 
2901 	mutex_unlock(&ctl_mutex);
2902 	return 0;
2903 
2904 out_new_dev:
2905 	blk_cleanup_queue(disk->queue);
2906 out_mem2:
2907 	put_disk(disk);
2908 out_mem:
2909 	if (pd->rb_pool)
2910 		mempool_destroy(pd->rb_pool);
2911 	kfree(pd);
2912 out_mutex:
2913 	mutex_unlock(&ctl_mutex);
2914 	printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2915 	return ret;
2916 }
2917 
2918 /*
2919  * Tear down mapping from pktcdvd device to CD-ROM device.
2920  */
2921 static int pkt_remove_dev(dev_t pkt_dev)
2922 {
2923 	struct pktcdvd_device *pd;
2924 	int idx;
2925 	int ret = 0;
2926 
2927 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2928 
2929 	for (idx = 0; idx < MAX_WRITERS; idx++) {
2930 		pd = pkt_devs[idx];
2931 		if (pd && (pd->pkt_dev == pkt_dev))
2932 			break;
2933 	}
2934 	if (idx == MAX_WRITERS) {
2935 		DPRINTK(DRIVER_NAME": dev not setup\n");
2936 		ret = -ENXIO;
2937 		goto out;
2938 	}
2939 
2940 	if (pd->refcnt > 0) {
2941 		ret = -EBUSY;
2942 		goto out;
2943 	}
2944 	if (!IS_ERR(pd->cdrw.thread))
2945 		kthread_stop(pd->cdrw.thread);
2946 
2947 	pkt_devs[idx] = NULL;
2948 
2949 	pkt_debugfs_dev_remove(pd);
2950 	pkt_sysfs_dev_remove(pd);
2951 
2952 	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2953 
2954 	remove_proc_entry(pd->name, pkt_proc);
2955 	DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2956 
2957 	del_gendisk(pd->disk);
2958 	blk_cleanup_queue(pd->disk->queue);
2959 	put_disk(pd->disk);
2960 
2961 	mempool_destroy(pd->rb_pool);
2962 	kfree(pd);
2963 
2964 	/* This is safe: open() is still holding a reference. */
2965 	module_put(THIS_MODULE);
2966 
2967 out:
2968 	mutex_unlock(&ctl_mutex);
2969 	return ret;
2970 }
2971 
2972 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2973 {
2974 	struct pktcdvd_device *pd;
2975 
2976 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2977 
2978 	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2979 	if (pd) {
2980 		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2981 		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2982 	} else {
2983 		ctrl_cmd->dev = 0;
2984 		ctrl_cmd->pkt_dev = 0;
2985 	}
2986 	ctrl_cmd->num_devices = MAX_WRITERS;
2987 
2988 	mutex_unlock(&ctl_mutex);
2989 }
2990 
2991 static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2992 {
2993 	void __user *argp = (void __user *)arg;
2994 	struct pkt_ctrl_command ctrl_cmd;
2995 	int ret = 0;
2996 	dev_t pkt_dev = 0;
2997 
2998 	if (cmd != PACKET_CTRL_CMD)
2999 		return -ENOTTY;
3000 
3001 	if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
3002 		return -EFAULT;
3003 
3004 	switch (ctrl_cmd.command) {
3005 	case PKT_CTRL_CMD_SETUP:
3006 		if (!capable(CAP_SYS_ADMIN))
3007 			return -EPERM;
3008 		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
3009 		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
3010 		break;
3011 	case PKT_CTRL_CMD_TEARDOWN:
3012 		if (!capable(CAP_SYS_ADMIN))
3013 			return -EPERM;
3014 		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
3015 		break;
3016 	case PKT_CTRL_CMD_STATUS:
3017 		pkt_get_status(&ctrl_cmd);
3018 		break;
3019 	default:
3020 		return -ENOTTY;
3021 	}
3022 
3023 	if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
3024 		return -EFAULT;
3025 	return ret;
3026 }
3027 
3028 #ifdef CONFIG_COMPAT
3029 static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
3030 {
3031 	return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
3032 }
3033 #endif
3034 
3035 static const struct file_operations pkt_ctl_fops = {
3036 	.open		= nonseekable_open,
3037 	.unlocked_ioctl	= pkt_ctl_ioctl,
3038 #ifdef CONFIG_COMPAT
3039 	.compat_ioctl	= pkt_ctl_compat_ioctl,
3040 #endif
3041 	.owner		= THIS_MODULE,
3042 	.llseek		= no_llseek,
3043 };
3044 
3045 static struct miscdevice pkt_misc = {
3046 	.minor 		= MISC_DYNAMIC_MINOR,
3047 	.name  		= DRIVER_NAME,
3048 	.nodename	= "pktcdvd/control",
3049 	.fops  		= &pkt_ctl_fops
3050 };
3051 
3052 static int __init pkt_init(void)
3053 {
3054 	int ret;
3055 
3056 	mutex_init(&ctl_mutex);
3057 
3058 	psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
3059 					sizeof(struct packet_stacked_data));
3060 	if (!psd_pool)
3061 		return -ENOMEM;
3062 
3063 	ret = register_blkdev(pktdev_major, DRIVER_NAME);
3064 	if (ret < 0) {
3065 		printk(DRIVER_NAME": Unable to register block device\n");
3066 		goto out2;
3067 	}
3068 	if (!pktdev_major)
3069 		pktdev_major = ret;
3070 
3071 	ret = pkt_sysfs_init();
3072 	if (ret)
3073 		goto out;
3074 
3075 	pkt_debugfs_init();
3076 
3077 	ret = misc_register(&pkt_misc);
3078 	if (ret) {
3079 		printk(DRIVER_NAME": Unable to register misc device\n");
3080 		goto out_misc;
3081 	}
3082 
3083 	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
3084 
3085 	return 0;
3086 
3087 out_misc:
3088 	pkt_debugfs_cleanup();
3089 	pkt_sysfs_cleanup();
3090 out:
3091 	unregister_blkdev(pktdev_major, DRIVER_NAME);
3092 out2:
3093 	mempool_destroy(psd_pool);
3094 	return ret;
3095 }
3096 
3097 static void __exit pkt_exit(void)
3098 {
3099 	remove_proc_entry("driver/"DRIVER_NAME, NULL);
3100 	misc_deregister(&pkt_misc);
3101 
3102 	pkt_debugfs_cleanup();
3103 	pkt_sysfs_cleanup();
3104 
3105 	unregister_blkdev(pktdev_major, DRIVER_NAME);
3106 	mempool_destroy(psd_pool);
3107 }
3108 
3109 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3110 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3111 MODULE_LICENSE("GPL");
3112 
3113 module_init(pkt_init);
3114 module_exit(pkt_exit);
3115