xref: /openbmc/linux/drivers/block/pktcdvd.c (revision a09d2831)
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/kthread.h>
52 #include <linux/errno.h>
53 #include <linux/spinlock.h>
54 #include <linux/file.h>
55 #include <linux/proc_fs.h>
56 #include <linux/seq_file.h>
57 #include <linux/miscdevice.h>
58 #include <linux/freezer.h>
59 #include <linux/mutex.h>
60 #include <scsi/scsi_cmnd.h>
61 #include <scsi/scsi_ioctl.h>
62 #include <scsi/scsi.h>
63 #include <linux/debugfs.h>
64 #include <linux/device.h>
65 
66 #include <asm/uaccess.h>
67 
68 #define DRIVER_NAME	"pktcdvd"
69 
70 #if PACKET_DEBUG
71 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
72 #else
73 #define DPRINTK(fmt, args...)
74 #endif
75 
76 #if PACKET_DEBUG > 1
77 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
78 #else
79 #define VPRINTK(fmt, args...)
80 #endif
81 
82 #define MAX_SPEED 0xffff
83 
84 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
85 
86 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
87 static struct proc_dir_entry *pkt_proc;
88 static int pktdev_major;
89 static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
90 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
91 static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
92 static mempool_t *psd_pool;
93 
94 static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
95 static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
96 
97 /* forward declaration */
98 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
99 static int pkt_remove_dev(dev_t pkt_dev);
100 static int pkt_seq_show(struct seq_file *m, void *p);
101 
102 
103 
104 /*
105  * create and register a pktcdvd kernel object.
106  */
107 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
108 					const char* name,
109 					struct kobject* parent,
110 					struct kobj_type* ktype)
111 {
112 	struct pktcdvd_kobj *p;
113 	int error;
114 
115 	p = kzalloc(sizeof(*p), GFP_KERNEL);
116 	if (!p)
117 		return NULL;
118 	p->pd = pd;
119 	error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
120 	if (error) {
121 		kobject_put(&p->kobj);
122 		return NULL;
123 	}
124 	kobject_uevent(&p->kobj, KOBJ_ADD);
125 	return p;
126 }
127 /*
128  * remove a pktcdvd kernel object.
129  */
130 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
131 {
132 	if (p)
133 		kobject_put(&p->kobj);
134 }
135 /*
136  * default release function for pktcdvd kernel objects.
137  */
138 static void pkt_kobj_release(struct kobject *kobj)
139 {
140 	kfree(to_pktcdvdkobj(kobj));
141 }
142 
143 
144 /**********************************************************
145  *
146  * sysfs interface for pktcdvd
147  * by (C) 2006  Thomas Maier <balagi@justmail.de>
148  *
149  **********************************************************/
150 
151 #define DEF_ATTR(_obj,_name,_mode) \
152 	static struct attribute _obj = { .name = _name, .mode = _mode }
153 
154 /**********************************************************
155   /sys/class/pktcdvd/pktcdvd[0-7]/
156                      stat/reset
157                      stat/packets_started
158                      stat/packets_finished
159                      stat/kb_written
160                      stat/kb_read
161                      stat/kb_read_gather
162                      write_queue/size
163                      write_queue/congestion_off
164                      write_queue/congestion_on
165  **********************************************************/
166 
167 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
168 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
169 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
170 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
171 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
172 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
173 
174 static struct attribute *kobj_pkt_attrs_stat[] = {
175 	&kobj_pkt_attr_st1,
176 	&kobj_pkt_attr_st2,
177 	&kobj_pkt_attr_st3,
178 	&kobj_pkt_attr_st4,
179 	&kobj_pkt_attr_st5,
180 	&kobj_pkt_attr_st6,
181 	NULL
182 };
183 
184 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
185 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
186 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
187 
188 static struct attribute *kobj_pkt_attrs_wqueue[] = {
189 	&kobj_pkt_attr_wq1,
190 	&kobj_pkt_attr_wq2,
191 	&kobj_pkt_attr_wq3,
192 	NULL
193 };
194 
195 static ssize_t kobj_pkt_show(struct kobject *kobj,
196 			struct attribute *attr, char *data)
197 {
198 	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
199 	int n = 0;
200 	int v;
201 	if (strcmp(attr->name, "packets_started") == 0) {
202 		n = sprintf(data, "%lu\n", pd->stats.pkt_started);
203 
204 	} else if (strcmp(attr->name, "packets_finished") == 0) {
205 		n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
206 
207 	} else if (strcmp(attr->name, "kb_written") == 0) {
208 		n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
209 
210 	} else if (strcmp(attr->name, "kb_read") == 0) {
211 		n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
212 
213 	} else if (strcmp(attr->name, "kb_read_gather") == 0) {
214 		n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
215 
216 	} else if (strcmp(attr->name, "size") == 0) {
217 		spin_lock(&pd->lock);
218 		v = pd->bio_queue_size;
219 		spin_unlock(&pd->lock);
220 		n = sprintf(data, "%d\n", v);
221 
222 	} else if (strcmp(attr->name, "congestion_off") == 0) {
223 		spin_lock(&pd->lock);
224 		v = pd->write_congestion_off;
225 		spin_unlock(&pd->lock);
226 		n = sprintf(data, "%d\n", v);
227 
228 	} else if (strcmp(attr->name, "congestion_on") == 0) {
229 		spin_lock(&pd->lock);
230 		v = pd->write_congestion_on;
231 		spin_unlock(&pd->lock);
232 		n = sprintf(data, "%d\n", v);
233 	}
234 	return n;
235 }
236 
237 static void init_write_congestion_marks(int* lo, int* hi)
238 {
239 	if (*hi > 0) {
240 		*hi = max(*hi, 500);
241 		*hi = min(*hi, 1000000);
242 		if (*lo <= 0)
243 			*lo = *hi - 100;
244 		else {
245 			*lo = min(*lo, *hi - 100);
246 			*lo = max(*lo, 100);
247 		}
248 	} else {
249 		*hi = -1;
250 		*lo = -1;
251 	}
252 }
253 
254 static ssize_t kobj_pkt_store(struct kobject *kobj,
255 			struct attribute *attr,
256 			const char *data, size_t len)
257 {
258 	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
259 	int val;
260 
261 	if (strcmp(attr->name, "reset") == 0 && len > 0) {
262 		pd->stats.pkt_started = 0;
263 		pd->stats.pkt_ended = 0;
264 		pd->stats.secs_w = 0;
265 		pd->stats.secs_rg = 0;
266 		pd->stats.secs_r = 0;
267 
268 	} else if (strcmp(attr->name, "congestion_off") == 0
269 		   && sscanf(data, "%d", &val) == 1) {
270 		spin_lock(&pd->lock);
271 		pd->write_congestion_off = val;
272 		init_write_congestion_marks(&pd->write_congestion_off,
273 					&pd->write_congestion_on);
274 		spin_unlock(&pd->lock);
275 
276 	} else if (strcmp(attr->name, "congestion_on") == 0
277 		   && sscanf(data, "%d", &val) == 1) {
278 		spin_lock(&pd->lock);
279 		pd->write_congestion_on = val;
280 		init_write_congestion_marks(&pd->write_congestion_off,
281 					&pd->write_congestion_on);
282 		spin_unlock(&pd->lock);
283 	}
284 	return len;
285 }
286 
287 static struct sysfs_ops kobj_pkt_ops = {
288 	.show = kobj_pkt_show,
289 	.store = kobj_pkt_store
290 };
291 static struct kobj_type kobj_pkt_type_stat = {
292 	.release = pkt_kobj_release,
293 	.sysfs_ops = &kobj_pkt_ops,
294 	.default_attrs = kobj_pkt_attrs_stat
295 };
296 static struct kobj_type kobj_pkt_type_wqueue = {
297 	.release = pkt_kobj_release,
298 	.sysfs_ops = &kobj_pkt_ops,
299 	.default_attrs = kobj_pkt_attrs_wqueue
300 };
301 
302 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
303 {
304 	if (class_pktcdvd) {
305 		pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
306 					"%s", pd->name);
307 		if (IS_ERR(pd->dev))
308 			pd->dev = NULL;
309 	}
310 	if (pd->dev) {
311 		pd->kobj_stat = pkt_kobj_create(pd, "stat",
312 					&pd->dev->kobj,
313 					&kobj_pkt_type_stat);
314 		pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
315 					&pd->dev->kobj,
316 					&kobj_pkt_type_wqueue);
317 	}
318 }
319 
320 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
321 {
322 	pkt_kobj_remove(pd->kobj_stat);
323 	pkt_kobj_remove(pd->kobj_wqueue);
324 	if (class_pktcdvd)
325 		device_destroy(class_pktcdvd, pd->pkt_dev);
326 }
327 
328 
329 /********************************************************************
330   /sys/class/pktcdvd/
331                      add            map block device
332                      remove         unmap packet dev
333                      device_map     show mappings
334  *******************************************************************/
335 
336 static void class_pktcdvd_release(struct class *cls)
337 {
338 	kfree(cls);
339 }
340 static ssize_t class_pktcdvd_show_map(struct class *c, char *data)
341 {
342 	int n = 0;
343 	int idx;
344 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
345 	for (idx = 0; idx < MAX_WRITERS; idx++) {
346 		struct pktcdvd_device *pd = pkt_devs[idx];
347 		if (!pd)
348 			continue;
349 		n += sprintf(data+n, "%s %u:%u %u:%u\n",
350 			pd->name,
351 			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
352 			MAJOR(pd->bdev->bd_dev),
353 			MINOR(pd->bdev->bd_dev));
354 	}
355 	mutex_unlock(&ctl_mutex);
356 	return n;
357 }
358 
359 static ssize_t class_pktcdvd_store_add(struct class *c, const char *buf,
360 					size_t count)
361 {
362 	unsigned int major, minor;
363 
364 	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
365 		/* pkt_setup_dev() expects caller to hold reference to self */
366 		if (!try_module_get(THIS_MODULE))
367 			return -ENODEV;
368 
369 		pkt_setup_dev(MKDEV(major, minor), NULL);
370 
371 		module_put(THIS_MODULE);
372 
373 		return count;
374 	}
375 
376 	return -EINVAL;
377 }
378 
379 static ssize_t class_pktcdvd_store_remove(struct class *c, const char *buf,
380 					size_t count)
381 {
382 	unsigned int major, minor;
383 	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
384 		pkt_remove_dev(MKDEV(major, minor));
385 		return count;
386 	}
387 	return -EINVAL;
388 }
389 
390 static struct class_attribute class_pktcdvd_attrs[] = {
391  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
392  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
393  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
394  __ATTR_NULL
395 };
396 
397 
398 static int pkt_sysfs_init(void)
399 {
400 	int ret = 0;
401 
402 	/*
403 	 * create control files in sysfs
404 	 * /sys/class/pktcdvd/...
405 	 */
406 	class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
407 	if (!class_pktcdvd)
408 		return -ENOMEM;
409 	class_pktcdvd->name = DRIVER_NAME;
410 	class_pktcdvd->owner = THIS_MODULE;
411 	class_pktcdvd->class_release = class_pktcdvd_release;
412 	class_pktcdvd->class_attrs = class_pktcdvd_attrs;
413 	ret = class_register(class_pktcdvd);
414 	if (ret) {
415 		kfree(class_pktcdvd);
416 		class_pktcdvd = NULL;
417 		printk(DRIVER_NAME": failed to create class pktcdvd\n");
418 		return ret;
419 	}
420 	return 0;
421 }
422 
423 static void pkt_sysfs_cleanup(void)
424 {
425 	if (class_pktcdvd)
426 		class_destroy(class_pktcdvd);
427 	class_pktcdvd = NULL;
428 }
429 
430 /********************************************************************
431   entries in debugfs
432 
433   /sys/kernel/debug/pktcdvd[0-7]/
434 			info
435 
436  *******************************************************************/
437 
438 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
439 {
440 	return pkt_seq_show(m, p);
441 }
442 
443 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
444 {
445 	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
446 }
447 
448 static const struct file_operations debug_fops = {
449 	.open		= pkt_debugfs_fops_open,
450 	.read		= seq_read,
451 	.llseek		= seq_lseek,
452 	.release	= single_release,
453 	.owner		= THIS_MODULE,
454 };
455 
456 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
457 {
458 	if (!pkt_debugfs_root)
459 		return;
460 	pd->dfs_f_info = NULL;
461 	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
462 	if (IS_ERR(pd->dfs_d_root)) {
463 		pd->dfs_d_root = NULL;
464 		return;
465 	}
466 	pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
467 				pd->dfs_d_root, pd, &debug_fops);
468 	if (IS_ERR(pd->dfs_f_info)) {
469 		pd->dfs_f_info = NULL;
470 		return;
471 	}
472 }
473 
474 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
475 {
476 	if (!pkt_debugfs_root)
477 		return;
478 	if (pd->dfs_f_info)
479 		debugfs_remove(pd->dfs_f_info);
480 	pd->dfs_f_info = NULL;
481 	if (pd->dfs_d_root)
482 		debugfs_remove(pd->dfs_d_root);
483 	pd->dfs_d_root = NULL;
484 }
485 
486 static void pkt_debugfs_init(void)
487 {
488 	pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
489 	if (IS_ERR(pkt_debugfs_root)) {
490 		pkt_debugfs_root = NULL;
491 		return;
492 	}
493 }
494 
495 static void pkt_debugfs_cleanup(void)
496 {
497 	if (!pkt_debugfs_root)
498 		return;
499 	debugfs_remove(pkt_debugfs_root);
500 	pkt_debugfs_root = NULL;
501 }
502 
503 /* ----------------------------------------------------------*/
504 
505 
506 static void pkt_bio_finished(struct pktcdvd_device *pd)
507 {
508 	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
509 	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
510 		VPRINTK(DRIVER_NAME": queue empty\n");
511 		atomic_set(&pd->iosched.attention, 1);
512 		wake_up(&pd->wqueue);
513 	}
514 }
515 
516 static void pkt_bio_destructor(struct bio *bio)
517 {
518 	kfree(bio->bi_io_vec);
519 	kfree(bio);
520 }
521 
522 static struct bio *pkt_bio_alloc(int nr_iovecs)
523 {
524 	struct bio_vec *bvl = NULL;
525 	struct bio *bio;
526 
527 	bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
528 	if (!bio)
529 		goto no_bio;
530 	bio_init(bio);
531 
532 	bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL);
533 	if (!bvl)
534 		goto no_bvl;
535 
536 	bio->bi_max_vecs = nr_iovecs;
537 	bio->bi_io_vec = bvl;
538 	bio->bi_destructor = pkt_bio_destructor;
539 
540 	return bio;
541 
542  no_bvl:
543 	kfree(bio);
544  no_bio:
545 	return NULL;
546 }
547 
548 /*
549  * Allocate a packet_data struct
550  */
551 static struct packet_data *pkt_alloc_packet_data(int frames)
552 {
553 	int i;
554 	struct packet_data *pkt;
555 
556 	pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
557 	if (!pkt)
558 		goto no_pkt;
559 
560 	pkt->frames = frames;
561 	pkt->w_bio = pkt_bio_alloc(frames);
562 	if (!pkt->w_bio)
563 		goto no_bio;
564 
565 	for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
566 		pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
567 		if (!pkt->pages[i])
568 			goto no_page;
569 	}
570 
571 	spin_lock_init(&pkt->lock);
572 
573 	for (i = 0; i < frames; i++) {
574 		struct bio *bio = pkt_bio_alloc(1);
575 		if (!bio)
576 			goto no_rd_bio;
577 		pkt->r_bios[i] = bio;
578 	}
579 
580 	return pkt;
581 
582 no_rd_bio:
583 	for (i = 0; i < frames; i++) {
584 		struct bio *bio = pkt->r_bios[i];
585 		if (bio)
586 			bio_put(bio);
587 	}
588 
589 no_page:
590 	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
591 		if (pkt->pages[i])
592 			__free_page(pkt->pages[i]);
593 	bio_put(pkt->w_bio);
594 no_bio:
595 	kfree(pkt);
596 no_pkt:
597 	return NULL;
598 }
599 
600 /*
601  * Free a packet_data struct
602  */
603 static void pkt_free_packet_data(struct packet_data *pkt)
604 {
605 	int i;
606 
607 	for (i = 0; i < pkt->frames; i++) {
608 		struct bio *bio = pkt->r_bios[i];
609 		if (bio)
610 			bio_put(bio);
611 	}
612 	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
613 		__free_page(pkt->pages[i]);
614 	bio_put(pkt->w_bio);
615 	kfree(pkt);
616 }
617 
618 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
619 {
620 	struct packet_data *pkt, *next;
621 
622 	BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
623 
624 	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
625 		pkt_free_packet_data(pkt);
626 	}
627 	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
628 }
629 
630 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
631 {
632 	struct packet_data *pkt;
633 
634 	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
635 
636 	while (nr_packets > 0) {
637 		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
638 		if (!pkt) {
639 			pkt_shrink_pktlist(pd);
640 			return 0;
641 		}
642 		pkt->id = nr_packets;
643 		pkt->pd = pd;
644 		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
645 		nr_packets--;
646 	}
647 	return 1;
648 }
649 
650 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
651 {
652 	struct rb_node *n = rb_next(&node->rb_node);
653 	if (!n)
654 		return NULL;
655 	return rb_entry(n, struct pkt_rb_node, rb_node);
656 }
657 
658 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
659 {
660 	rb_erase(&node->rb_node, &pd->bio_queue);
661 	mempool_free(node, pd->rb_pool);
662 	pd->bio_queue_size--;
663 	BUG_ON(pd->bio_queue_size < 0);
664 }
665 
666 /*
667  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
668  */
669 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
670 {
671 	struct rb_node *n = pd->bio_queue.rb_node;
672 	struct rb_node *next;
673 	struct pkt_rb_node *tmp;
674 
675 	if (!n) {
676 		BUG_ON(pd->bio_queue_size > 0);
677 		return NULL;
678 	}
679 
680 	for (;;) {
681 		tmp = rb_entry(n, struct pkt_rb_node, rb_node);
682 		if (s <= tmp->bio->bi_sector)
683 			next = n->rb_left;
684 		else
685 			next = n->rb_right;
686 		if (!next)
687 			break;
688 		n = next;
689 	}
690 
691 	if (s > tmp->bio->bi_sector) {
692 		tmp = pkt_rbtree_next(tmp);
693 		if (!tmp)
694 			return NULL;
695 	}
696 	BUG_ON(s > tmp->bio->bi_sector);
697 	return tmp;
698 }
699 
700 /*
701  * Insert a node into the pd->bio_queue rb tree.
702  */
703 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
704 {
705 	struct rb_node **p = &pd->bio_queue.rb_node;
706 	struct rb_node *parent = NULL;
707 	sector_t s = node->bio->bi_sector;
708 	struct pkt_rb_node *tmp;
709 
710 	while (*p) {
711 		parent = *p;
712 		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
713 		if (s < tmp->bio->bi_sector)
714 			p = &(*p)->rb_left;
715 		else
716 			p = &(*p)->rb_right;
717 	}
718 	rb_link_node(&node->rb_node, parent, p);
719 	rb_insert_color(&node->rb_node, &pd->bio_queue);
720 	pd->bio_queue_size++;
721 }
722 
723 /*
724  * Add a bio to a single linked list defined by its head and tail pointers.
725  */
726 static void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
727 {
728 	bio->bi_next = NULL;
729 	if (*list_tail) {
730 		BUG_ON((*list_head) == NULL);
731 		(*list_tail)->bi_next = bio;
732 		(*list_tail) = bio;
733 	} else {
734 		BUG_ON((*list_head) != NULL);
735 		(*list_head) = bio;
736 		(*list_tail) = bio;
737 	}
738 }
739 
740 /*
741  * Remove and return the first bio from a single linked list defined by its
742  * head and tail pointers.
743  */
744 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
745 {
746 	struct bio *bio;
747 
748 	if (*list_head == NULL)
749 		return NULL;
750 
751 	bio = *list_head;
752 	*list_head = bio->bi_next;
753 	if (*list_head == NULL)
754 		*list_tail = NULL;
755 
756 	bio->bi_next = NULL;
757 	return bio;
758 }
759 
760 /*
761  * Send a packet_command to the underlying block device and
762  * wait for completion.
763  */
764 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
765 {
766 	struct request_queue *q = bdev_get_queue(pd->bdev);
767 	struct request *rq;
768 	int ret = 0;
769 
770 	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
771 			     WRITE : READ, __GFP_WAIT);
772 
773 	if (cgc->buflen) {
774 		if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
775 			goto out;
776 	}
777 
778 	rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
779 	memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
780 
781 	rq->timeout = 60*HZ;
782 	rq->cmd_type = REQ_TYPE_BLOCK_PC;
783 	rq->cmd_flags |= REQ_HARDBARRIER;
784 	if (cgc->quiet)
785 		rq->cmd_flags |= REQ_QUIET;
786 
787 	blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
788 	if (rq->errors)
789 		ret = -EIO;
790 out:
791 	blk_put_request(rq);
792 	return ret;
793 }
794 
795 /*
796  * A generic sense dump / resolve mechanism should be implemented across
797  * all ATAPI + SCSI devices.
798  */
799 static void pkt_dump_sense(struct packet_command *cgc)
800 {
801 	static char *info[9] = { "No sense", "Recovered error", "Not ready",
802 				 "Medium error", "Hardware error", "Illegal request",
803 				 "Unit attention", "Data protect", "Blank check" };
804 	int i;
805 	struct request_sense *sense = cgc->sense;
806 
807 	printk(DRIVER_NAME":");
808 	for (i = 0; i < CDROM_PACKET_SIZE; i++)
809 		printk(" %02x", cgc->cmd[i]);
810 	printk(" - ");
811 
812 	if (sense == NULL) {
813 		printk("no sense\n");
814 		return;
815 	}
816 
817 	printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
818 
819 	if (sense->sense_key > 8) {
820 		printk(" (INVALID)\n");
821 		return;
822 	}
823 
824 	printk(" (%s)\n", info[sense->sense_key]);
825 }
826 
827 /*
828  * flush the drive cache to media
829  */
830 static int pkt_flush_cache(struct pktcdvd_device *pd)
831 {
832 	struct packet_command cgc;
833 
834 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
835 	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
836 	cgc.quiet = 1;
837 
838 	/*
839 	 * the IMMED bit -- we default to not setting it, although that
840 	 * would allow a much faster close, this is safer
841 	 */
842 #if 0
843 	cgc.cmd[1] = 1 << 1;
844 #endif
845 	return pkt_generic_packet(pd, &cgc);
846 }
847 
848 /*
849  * speed is given as the normal factor, e.g. 4 for 4x
850  */
851 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
852 				unsigned write_speed, unsigned read_speed)
853 {
854 	struct packet_command cgc;
855 	struct request_sense sense;
856 	int ret;
857 
858 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
859 	cgc.sense = &sense;
860 	cgc.cmd[0] = GPCMD_SET_SPEED;
861 	cgc.cmd[2] = (read_speed >> 8) & 0xff;
862 	cgc.cmd[3] = read_speed & 0xff;
863 	cgc.cmd[4] = (write_speed >> 8) & 0xff;
864 	cgc.cmd[5] = write_speed & 0xff;
865 
866 	if ((ret = pkt_generic_packet(pd, &cgc)))
867 		pkt_dump_sense(&cgc);
868 
869 	return ret;
870 }
871 
872 /*
873  * Queue a bio for processing by the low-level CD device. Must be called
874  * from process context.
875  */
876 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
877 {
878 	spin_lock(&pd->iosched.lock);
879 	if (bio_data_dir(bio) == READ) {
880 		pkt_add_list_last(bio, &pd->iosched.read_queue,
881 				  &pd->iosched.read_queue_tail);
882 	} else {
883 		pkt_add_list_last(bio, &pd->iosched.write_queue,
884 				  &pd->iosched.write_queue_tail);
885 	}
886 	spin_unlock(&pd->iosched.lock);
887 
888 	atomic_set(&pd->iosched.attention, 1);
889 	wake_up(&pd->wqueue);
890 }
891 
892 /*
893  * Process the queued read/write requests. This function handles special
894  * requirements for CDRW drives:
895  * - A cache flush command must be inserted before a read request if the
896  *   previous request was a write.
897  * - Switching between reading and writing is slow, so don't do it more often
898  *   than necessary.
899  * - Optimize for throughput at the expense of latency. This means that streaming
900  *   writes will never be interrupted by a read, but if the drive has to seek
901  *   before the next write, switch to reading instead if there are any pending
902  *   read requests.
903  * - Set the read speed according to current usage pattern. When only reading
904  *   from the device, it's best to use the highest possible read speed, but
905  *   when switching often between reading and writing, it's better to have the
906  *   same read and write speeds.
907  */
908 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
909 {
910 
911 	if (atomic_read(&pd->iosched.attention) == 0)
912 		return;
913 	atomic_set(&pd->iosched.attention, 0);
914 
915 	for (;;) {
916 		struct bio *bio;
917 		int reads_queued, writes_queued;
918 
919 		spin_lock(&pd->iosched.lock);
920 		reads_queued = (pd->iosched.read_queue != NULL);
921 		writes_queued = (pd->iosched.write_queue != NULL);
922 		spin_unlock(&pd->iosched.lock);
923 
924 		if (!reads_queued && !writes_queued)
925 			break;
926 
927 		if (pd->iosched.writing) {
928 			int need_write_seek = 1;
929 			spin_lock(&pd->iosched.lock);
930 			bio = pd->iosched.write_queue;
931 			spin_unlock(&pd->iosched.lock);
932 			if (bio && (bio->bi_sector == pd->iosched.last_write))
933 				need_write_seek = 0;
934 			if (need_write_seek && reads_queued) {
935 				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
936 					VPRINTK(DRIVER_NAME": write, waiting\n");
937 					break;
938 				}
939 				pkt_flush_cache(pd);
940 				pd->iosched.writing = 0;
941 			}
942 		} else {
943 			if (!reads_queued && writes_queued) {
944 				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
945 					VPRINTK(DRIVER_NAME": read, waiting\n");
946 					break;
947 				}
948 				pd->iosched.writing = 1;
949 			}
950 		}
951 
952 		spin_lock(&pd->iosched.lock);
953 		if (pd->iosched.writing) {
954 			bio = pkt_get_list_first(&pd->iosched.write_queue,
955 						 &pd->iosched.write_queue_tail);
956 		} else {
957 			bio = pkt_get_list_first(&pd->iosched.read_queue,
958 						 &pd->iosched.read_queue_tail);
959 		}
960 		spin_unlock(&pd->iosched.lock);
961 
962 		if (!bio)
963 			continue;
964 
965 		if (bio_data_dir(bio) == READ)
966 			pd->iosched.successive_reads += bio->bi_size >> 10;
967 		else {
968 			pd->iosched.successive_reads = 0;
969 			pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
970 		}
971 		if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
972 			if (pd->read_speed == pd->write_speed) {
973 				pd->read_speed = MAX_SPEED;
974 				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
975 			}
976 		} else {
977 			if (pd->read_speed != pd->write_speed) {
978 				pd->read_speed = pd->write_speed;
979 				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
980 			}
981 		}
982 
983 		atomic_inc(&pd->cdrw.pending_bios);
984 		generic_make_request(bio);
985 	}
986 }
987 
988 /*
989  * Special care is needed if the underlying block device has a small
990  * max_phys_segments value.
991  */
992 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
993 {
994 	if ((pd->settings.size << 9) / CD_FRAMESIZE
995 	    <= queue_max_phys_segments(q)) {
996 		/*
997 		 * The cdrom device can handle one segment/frame
998 		 */
999 		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
1000 		return 0;
1001 	} else if ((pd->settings.size << 9) / PAGE_SIZE
1002 		   <= queue_max_phys_segments(q)) {
1003 		/*
1004 		 * We can handle this case at the expense of some extra memory
1005 		 * copies during write operations
1006 		 */
1007 		set_bit(PACKET_MERGE_SEGS, &pd->flags);
1008 		return 0;
1009 	} else {
1010 		printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
1011 		return -EIO;
1012 	}
1013 }
1014 
1015 /*
1016  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
1017  */
1018 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
1019 {
1020 	unsigned int copy_size = CD_FRAMESIZE;
1021 
1022 	while (copy_size > 0) {
1023 		struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
1024 		void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
1025 			src_bvl->bv_offset + offs;
1026 		void *vto = page_address(dst_page) + dst_offs;
1027 		int len = min_t(int, copy_size, src_bvl->bv_len - offs);
1028 
1029 		BUG_ON(len < 0);
1030 		memcpy(vto, vfrom, len);
1031 		kunmap_atomic(vfrom, KM_USER0);
1032 
1033 		seg++;
1034 		offs = 0;
1035 		dst_offs += len;
1036 		copy_size -= len;
1037 	}
1038 }
1039 
1040 /*
1041  * Copy all data for this packet to pkt->pages[], so that
1042  * a) The number of required segments for the write bio is minimized, which
1043  *    is necessary for some scsi controllers.
1044  * b) The data can be used as cache to avoid read requests if we receive a
1045  *    new write request for the same zone.
1046  */
1047 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
1048 {
1049 	int f, p, offs;
1050 
1051 	/* Copy all data to pkt->pages[] */
1052 	p = 0;
1053 	offs = 0;
1054 	for (f = 0; f < pkt->frames; f++) {
1055 		if (bvec[f].bv_page != pkt->pages[p]) {
1056 			void *vfrom = kmap_atomic(bvec[f].bv_page, KM_USER0) + bvec[f].bv_offset;
1057 			void *vto = page_address(pkt->pages[p]) + offs;
1058 			memcpy(vto, vfrom, CD_FRAMESIZE);
1059 			kunmap_atomic(vfrom, KM_USER0);
1060 			bvec[f].bv_page = pkt->pages[p];
1061 			bvec[f].bv_offset = offs;
1062 		} else {
1063 			BUG_ON(bvec[f].bv_offset != offs);
1064 		}
1065 		offs += CD_FRAMESIZE;
1066 		if (offs >= PAGE_SIZE) {
1067 			offs = 0;
1068 			p++;
1069 		}
1070 	}
1071 }
1072 
1073 static void pkt_end_io_read(struct bio *bio, int err)
1074 {
1075 	struct packet_data *pkt = bio->bi_private;
1076 	struct pktcdvd_device *pd = pkt->pd;
1077 	BUG_ON(!pd);
1078 
1079 	VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
1080 		(unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
1081 
1082 	if (err)
1083 		atomic_inc(&pkt->io_errors);
1084 	if (atomic_dec_and_test(&pkt->io_wait)) {
1085 		atomic_inc(&pkt->run_sm);
1086 		wake_up(&pd->wqueue);
1087 	}
1088 	pkt_bio_finished(pd);
1089 }
1090 
1091 static void pkt_end_io_packet_write(struct bio *bio, int err)
1092 {
1093 	struct packet_data *pkt = bio->bi_private;
1094 	struct pktcdvd_device *pd = pkt->pd;
1095 	BUG_ON(!pd);
1096 
1097 	VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1098 
1099 	pd->stats.pkt_ended++;
1100 
1101 	pkt_bio_finished(pd);
1102 	atomic_dec(&pkt->io_wait);
1103 	atomic_inc(&pkt->run_sm);
1104 	wake_up(&pd->wqueue);
1105 }
1106 
1107 /*
1108  * Schedule reads for the holes in a packet
1109  */
1110 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1111 {
1112 	int frames_read = 0;
1113 	struct bio *bio;
1114 	int f;
1115 	char written[PACKET_MAX_SIZE];
1116 
1117 	BUG_ON(!pkt->orig_bios);
1118 
1119 	atomic_set(&pkt->io_wait, 0);
1120 	atomic_set(&pkt->io_errors, 0);
1121 
1122 	/*
1123 	 * Figure out which frames we need to read before we can write.
1124 	 */
1125 	memset(written, 0, sizeof(written));
1126 	spin_lock(&pkt->lock);
1127 	for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1128 		int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1129 		int num_frames = bio->bi_size / CD_FRAMESIZE;
1130 		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1131 		BUG_ON(first_frame < 0);
1132 		BUG_ON(first_frame + num_frames > pkt->frames);
1133 		for (f = first_frame; f < first_frame + num_frames; f++)
1134 			written[f] = 1;
1135 	}
1136 	spin_unlock(&pkt->lock);
1137 
1138 	if (pkt->cache_valid) {
1139 		VPRINTK("pkt_gather_data: zone %llx cached\n",
1140 			(unsigned long long)pkt->sector);
1141 		goto out_account;
1142 	}
1143 
1144 	/*
1145 	 * Schedule reads for missing parts of the packet.
1146 	 */
1147 	for (f = 0; f < pkt->frames; f++) {
1148 		struct bio_vec *vec;
1149 
1150 		int p, offset;
1151 		if (written[f])
1152 			continue;
1153 		bio = pkt->r_bios[f];
1154 		vec = bio->bi_io_vec;
1155 		bio_init(bio);
1156 		bio->bi_max_vecs = 1;
1157 		bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1158 		bio->bi_bdev = pd->bdev;
1159 		bio->bi_end_io = pkt_end_io_read;
1160 		bio->bi_private = pkt;
1161 		bio->bi_io_vec = vec;
1162 		bio->bi_destructor = pkt_bio_destructor;
1163 
1164 		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1165 		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1166 		VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1167 			f, pkt->pages[p], offset);
1168 		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1169 			BUG();
1170 
1171 		atomic_inc(&pkt->io_wait);
1172 		bio->bi_rw = READ;
1173 		pkt_queue_bio(pd, bio);
1174 		frames_read++;
1175 	}
1176 
1177 out_account:
1178 	VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1179 		frames_read, (unsigned long long)pkt->sector);
1180 	pd->stats.pkt_started++;
1181 	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1182 }
1183 
1184 /*
1185  * Find a packet matching zone, or the least recently used packet if
1186  * there is no match.
1187  */
1188 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1189 {
1190 	struct packet_data *pkt;
1191 
1192 	list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1193 		if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1194 			list_del_init(&pkt->list);
1195 			if (pkt->sector != zone)
1196 				pkt->cache_valid = 0;
1197 			return pkt;
1198 		}
1199 	}
1200 	BUG();
1201 	return NULL;
1202 }
1203 
1204 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1205 {
1206 	if (pkt->cache_valid) {
1207 		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1208 	} else {
1209 		list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1210 	}
1211 }
1212 
1213 /*
1214  * recover a failed write, query for relocation if possible
1215  *
1216  * returns 1 if recovery is possible, or 0 if not
1217  *
1218  */
1219 static int pkt_start_recovery(struct packet_data *pkt)
1220 {
1221 	/*
1222 	 * FIXME. We need help from the file system to implement
1223 	 * recovery handling.
1224 	 */
1225 	return 0;
1226 #if 0
1227 	struct request *rq = pkt->rq;
1228 	struct pktcdvd_device *pd = rq->rq_disk->private_data;
1229 	struct block_device *pkt_bdev;
1230 	struct super_block *sb = NULL;
1231 	unsigned long old_block, new_block;
1232 	sector_t new_sector;
1233 
1234 	pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1235 	if (pkt_bdev) {
1236 		sb = get_super(pkt_bdev);
1237 		bdput(pkt_bdev);
1238 	}
1239 
1240 	if (!sb)
1241 		return 0;
1242 
1243 	if (!sb->s_op || !sb->s_op->relocate_blocks)
1244 		goto out;
1245 
1246 	old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1247 	if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1248 		goto out;
1249 
1250 	new_sector = new_block * (CD_FRAMESIZE >> 9);
1251 	pkt->sector = new_sector;
1252 
1253 	pkt->bio->bi_sector = new_sector;
1254 	pkt->bio->bi_next = NULL;
1255 	pkt->bio->bi_flags = 1 << BIO_UPTODATE;
1256 	pkt->bio->bi_idx = 0;
1257 
1258 	BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
1259 	BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
1260 	BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
1261 	BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
1262 	BUG_ON(pkt->bio->bi_private != pkt);
1263 
1264 	drop_super(sb);
1265 	return 1;
1266 
1267 out:
1268 	drop_super(sb);
1269 	return 0;
1270 #endif
1271 }
1272 
1273 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1274 {
1275 #if PACKET_DEBUG > 1
1276 	static const char *state_name[] = {
1277 		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1278 	};
1279 	enum packet_data_state old_state = pkt->state;
1280 	VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1281 		state_name[old_state], state_name[state]);
1282 #endif
1283 	pkt->state = state;
1284 }
1285 
1286 /*
1287  * Scan the work queue to see if we can start a new packet.
1288  * returns non-zero if any work was done.
1289  */
1290 static int pkt_handle_queue(struct pktcdvd_device *pd)
1291 {
1292 	struct packet_data *pkt, *p;
1293 	struct bio *bio = NULL;
1294 	sector_t zone = 0; /* Suppress gcc warning */
1295 	struct pkt_rb_node *node, *first_node;
1296 	struct rb_node *n;
1297 	int wakeup;
1298 
1299 	VPRINTK("handle_queue\n");
1300 
1301 	atomic_set(&pd->scan_queue, 0);
1302 
1303 	if (list_empty(&pd->cdrw.pkt_free_list)) {
1304 		VPRINTK("handle_queue: no pkt\n");
1305 		return 0;
1306 	}
1307 
1308 	/*
1309 	 * Try to find a zone we are not already working on.
1310 	 */
1311 	spin_lock(&pd->lock);
1312 	first_node = pkt_rbtree_find(pd, pd->current_sector);
1313 	if (!first_node) {
1314 		n = rb_first(&pd->bio_queue);
1315 		if (n)
1316 			first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1317 	}
1318 	node = first_node;
1319 	while (node) {
1320 		bio = node->bio;
1321 		zone = ZONE(bio->bi_sector, pd);
1322 		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1323 			if (p->sector == zone) {
1324 				bio = NULL;
1325 				goto try_next_bio;
1326 			}
1327 		}
1328 		break;
1329 try_next_bio:
1330 		node = pkt_rbtree_next(node);
1331 		if (!node) {
1332 			n = rb_first(&pd->bio_queue);
1333 			if (n)
1334 				node = rb_entry(n, struct pkt_rb_node, rb_node);
1335 		}
1336 		if (node == first_node)
1337 			node = NULL;
1338 	}
1339 	spin_unlock(&pd->lock);
1340 	if (!bio) {
1341 		VPRINTK("handle_queue: no bio\n");
1342 		return 0;
1343 	}
1344 
1345 	pkt = pkt_get_packet_data(pd, zone);
1346 
1347 	pd->current_sector = zone + pd->settings.size;
1348 	pkt->sector = zone;
1349 	BUG_ON(pkt->frames != pd->settings.size >> 2);
1350 	pkt->write_size = 0;
1351 
1352 	/*
1353 	 * Scan work queue for bios in the same zone and link them
1354 	 * to this packet.
1355 	 */
1356 	spin_lock(&pd->lock);
1357 	VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1358 	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1359 		bio = node->bio;
1360 		VPRINTK("pkt_handle_queue: found zone=%llx\n",
1361 			(unsigned long long)ZONE(bio->bi_sector, pd));
1362 		if (ZONE(bio->bi_sector, pd) != zone)
1363 			break;
1364 		pkt_rbtree_erase(pd, node);
1365 		spin_lock(&pkt->lock);
1366 		pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
1367 		pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1368 		spin_unlock(&pkt->lock);
1369 	}
1370 	/* check write congestion marks, and if bio_queue_size is
1371 	   below, wake up any waiters */
1372 	wakeup = (pd->write_congestion_on > 0
1373 	 		&& pd->bio_queue_size <= pd->write_congestion_off);
1374 	spin_unlock(&pd->lock);
1375 	if (wakeup) {
1376 		clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1377 					BLK_RW_ASYNC);
1378 	}
1379 
1380 	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1381 	pkt_set_state(pkt, PACKET_WAITING_STATE);
1382 	atomic_set(&pkt->run_sm, 1);
1383 
1384 	spin_lock(&pd->cdrw.active_list_lock);
1385 	list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1386 	spin_unlock(&pd->cdrw.active_list_lock);
1387 
1388 	return 1;
1389 }
1390 
1391 /*
1392  * Assemble a bio to write one packet and queue the bio for processing
1393  * by the underlying block device.
1394  */
1395 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1396 {
1397 	struct bio *bio;
1398 	int f;
1399 	int frames_write;
1400 	struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1401 
1402 	for (f = 0; f < pkt->frames; f++) {
1403 		bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1404 		bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1405 	}
1406 
1407 	/*
1408 	 * Fill-in bvec with data from orig_bios.
1409 	 */
1410 	frames_write = 0;
1411 	spin_lock(&pkt->lock);
1412 	for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1413 		int segment = bio->bi_idx;
1414 		int src_offs = 0;
1415 		int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1416 		int num_frames = bio->bi_size / CD_FRAMESIZE;
1417 		BUG_ON(first_frame < 0);
1418 		BUG_ON(first_frame + num_frames > pkt->frames);
1419 		for (f = first_frame; f < first_frame + num_frames; f++) {
1420 			struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1421 
1422 			while (src_offs >= src_bvl->bv_len) {
1423 				src_offs -= src_bvl->bv_len;
1424 				segment++;
1425 				BUG_ON(segment >= bio->bi_vcnt);
1426 				src_bvl = bio_iovec_idx(bio, segment);
1427 			}
1428 
1429 			if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1430 				bvec[f].bv_page = src_bvl->bv_page;
1431 				bvec[f].bv_offset = src_bvl->bv_offset + src_offs;
1432 			} else {
1433 				pkt_copy_bio_data(bio, segment, src_offs,
1434 						  bvec[f].bv_page, bvec[f].bv_offset);
1435 			}
1436 			src_offs += CD_FRAMESIZE;
1437 			frames_write++;
1438 		}
1439 	}
1440 	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1441 	spin_unlock(&pkt->lock);
1442 
1443 	VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1444 		frames_write, (unsigned long long)pkt->sector);
1445 	BUG_ON(frames_write != pkt->write_size);
1446 
1447 	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1448 		pkt_make_local_copy(pkt, bvec);
1449 		pkt->cache_valid = 1;
1450 	} else {
1451 		pkt->cache_valid = 0;
1452 	}
1453 
1454 	/* Start the write request */
1455 	bio_init(pkt->w_bio);
1456 	pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1457 	pkt->w_bio->bi_sector = pkt->sector;
1458 	pkt->w_bio->bi_bdev = pd->bdev;
1459 	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1460 	pkt->w_bio->bi_private = pkt;
1461 	pkt->w_bio->bi_io_vec = bvec;
1462 	pkt->w_bio->bi_destructor = pkt_bio_destructor;
1463 	for (f = 0; f < pkt->frames; f++)
1464 		if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1465 			BUG();
1466 	VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1467 
1468 	atomic_set(&pkt->io_wait, 1);
1469 	pkt->w_bio->bi_rw = WRITE;
1470 	pkt_queue_bio(pd, pkt->w_bio);
1471 }
1472 
1473 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1474 {
1475 	struct bio *bio, *next;
1476 
1477 	if (!uptodate)
1478 		pkt->cache_valid = 0;
1479 
1480 	/* Finish all bios corresponding to this packet */
1481 	bio = pkt->orig_bios;
1482 	while (bio) {
1483 		next = bio->bi_next;
1484 		bio->bi_next = NULL;
1485 		bio_endio(bio, uptodate ? 0 : -EIO);
1486 		bio = next;
1487 	}
1488 	pkt->orig_bios = pkt->orig_bios_tail = NULL;
1489 }
1490 
1491 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1492 {
1493 	int uptodate;
1494 
1495 	VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1496 
1497 	for (;;) {
1498 		switch (pkt->state) {
1499 		case PACKET_WAITING_STATE:
1500 			if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1501 				return;
1502 
1503 			pkt->sleep_time = 0;
1504 			pkt_gather_data(pd, pkt);
1505 			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1506 			break;
1507 
1508 		case PACKET_READ_WAIT_STATE:
1509 			if (atomic_read(&pkt->io_wait) > 0)
1510 				return;
1511 
1512 			if (atomic_read(&pkt->io_errors) > 0) {
1513 				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1514 			} else {
1515 				pkt_start_write(pd, pkt);
1516 			}
1517 			break;
1518 
1519 		case PACKET_WRITE_WAIT_STATE:
1520 			if (atomic_read(&pkt->io_wait) > 0)
1521 				return;
1522 
1523 			if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1524 				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1525 			} else {
1526 				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1527 			}
1528 			break;
1529 
1530 		case PACKET_RECOVERY_STATE:
1531 			if (pkt_start_recovery(pkt)) {
1532 				pkt_start_write(pd, pkt);
1533 			} else {
1534 				VPRINTK("No recovery possible\n");
1535 				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1536 			}
1537 			break;
1538 
1539 		case PACKET_FINISHED_STATE:
1540 			uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1541 			pkt_finish_packet(pkt, uptodate);
1542 			return;
1543 
1544 		default:
1545 			BUG();
1546 			break;
1547 		}
1548 	}
1549 }
1550 
1551 static void pkt_handle_packets(struct pktcdvd_device *pd)
1552 {
1553 	struct packet_data *pkt, *next;
1554 
1555 	VPRINTK("pkt_handle_packets\n");
1556 
1557 	/*
1558 	 * Run state machine for active packets
1559 	 */
1560 	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1561 		if (atomic_read(&pkt->run_sm) > 0) {
1562 			atomic_set(&pkt->run_sm, 0);
1563 			pkt_run_state_machine(pd, pkt);
1564 		}
1565 	}
1566 
1567 	/*
1568 	 * Move no longer active packets to the free list
1569 	 */
1570 	spin_lock(&pd->cdrw.active_list_lock);
1571 	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1572 		if (pkt->state == PACKET_FINISHED_STATE) {
1573 			list_del(&pkt->list);
1574 			pkt_put_packet_data(pd, pkt);
1575 			pkt_set_state(pkt, PACKET_IDLE_STATE);
1576 			atomic_set(&pd->scan_queue, 1);
1577 		}
1578 	}
1579 	spin_unlock(&pd->cdrw.active_list_lock);
1580 }
1581 
1582 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1583 {
1584 	struct packet_data *pkt;
1585 	int i;
1586 
1587 	for (i = 0; i < PACKET_NUM_STATES; i++)
1588 		states[i] = 0;
1589 
1590 	spin_lock(&pd->cdrw.active_list_lock);
1591 	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1592 		states[pkt->state]++;
1593 	}
1594 	spin_unlock(&pd->cdrw.active_list_lock);
1595 }
1596 
1597 /*
1598  * kcdrwd is woken up when writes have been queued for one of our
1599  * registered devices
1600  */
1601 static int kcdrwd(void *foobar)
1602 {
1603 	struct pktcdvd_device *pd = foobar;
1604 	struct packet_data *pkt;
1605 	long min_sleep_time, residue;
1606 
1607 	set_user_nice(current, -20);
1608 	set_freezable();
1609 
1610 	for (;;) {
1611 		DECLARE_WAITQUEUE(wait, current);
1612 
1613 		/*
1614 		 * Wait until there is something to do
1615 		 */
1616 		add_wait_queue(&pd->wqueue, &wait);
1617 		for (;;) {
1618 			set_current_state(TASK_INTERRUPTIBLE);
1619 
1620 			/* Check if we need to run pkt_handle_queue */
1621 			if (atomic_read(&pd->scan_queue) > 0)
1622 				goto work_to_do;
1623 
1624 			/* Check if we need to run the state machine for some packet */
1625 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1626 				if (atomic_read(&pkt->run_sm) > 0)
1627 					goto work_to_do;
1628 			}
1629 
1630 			/* Check if we need to process the iosched queues */
1631 			if (atomic_read(&pd->iosched.attention) != 0)
1632 				goto work_to_do;
1633 
1634 			/* Otherwise, go to sleep */
1635 			if (PACKET_DEBUG > 1) {
1636 				int states[PACKET_NUM_STATES];
1637 				pkt_count_states(pd, states);
1638 				VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1639 					states[0], states[1], states[2], states[3],
1640 					states[4], states[5]);
1641 			}
1642 
1643 			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1644 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1645 				if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1646 					min_sleep_time = pkt->sleep_time;
1647 			}
1648 
1649 			generic_unplug_device(bdev_get_queue(pd->bdev));
1650 
1651 			VPRINTK("kcdrwd: sleeping\n");
1652 			residue = schedule_timeout(min_sleep_time);
1653 			VPRINTK("kcdrwd: wake up\n");
1654 
1655 			/* make swsusp happy with our thread */
1656 			try_to_freeze();
1657 
1658 			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1659 				if (!pkt->sleep_time)
1660 					continue;
1661 				pkt->sleep_time -= min_sleep_time - residue;
1662 				if (pkt->sleep_time <= 0) {
1663 					pkt->sleep_time = 0;
1664 					atomic_inc(&pkt->run_sm);
1665 				}
1666 			}
1667 
1668 			if (kthread_should_stop())
1669 				break;
1670 		}
1671 work_to_do:
1672 		set_current_state(TASK_RUNNING);
1673 		remove_wait_queue(&pd->wqueue, &wait);
1674 
1675 		if (kthread_should_stop())
1676 			break;
1677 
1678 		/*
1679 		 * if pkt_handle_queue returns true, we can queue
1680 		 * another request.
1681 		 */
1682 		while (pkt_handle_queue(pd))
1683 			;
1684 
1685 		/*
1686 		 * Handle packet state machine
1687 		 */
1688 		pkt_handle_packets(pd);
1689 
1690 		/*
1691 		 * Handle iosched queues
1692 		 */
1693 		pkt_iosched_process_queue(pd);
1694 	}
1695 
1696 	return 0;
1697 }
1698 
1699 static void pkt_print_settings(struct pktcdvd_device *pd)
1700 {
1701 	printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1702 	printk("%u blocks, ", pd->settings.size >> 2);
1703 	printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1704 }
1705 
1706 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1707 {
1708 	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1709 
1710 	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1711 	cgc->cmd[2] = page_code | (page_control << 6);
1712 	cgc->cmd[7] = cgc->buflen >> 8;
1713 	cgc->cmd[8] = cgc->buflen & 0xff;
1714 	cgc->data_direction = CGC_DATA_READ;
1715 	return pkt_generic_packet(pd, cgc);
1716 }
1717 
1718 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1719 {
1720 	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1721 	memset(cgc->buffer, 0, 2);
1722 	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1723 	cgc->cmd[1] = 0x10;		/* PF */
1724 	cgc->cmd[7] = cgc->buflen >> 8;
1725 	cgc->cmd[8] = cgc->buflen & 0xff;
1726 	cgc->data_direction = CGC_DATA_WRITE;
1727 	return pkt_generic_packet(pd, cgc);
1728 }
1729 
1730 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1731 {
1732 	struct packet_command cgc;
1733 	int ret;
1734 
1735 	/* set up command and get the disc info */
1736 	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1737 	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1738 	cgc.cmd[8] = cgc.buflen = 2;
1739 	cgc.quiet = 1;
1740 
1741 	if ((ret = pkt_generic_packet(pd, &cgc)))
1742 		return ret;
1743 
1744 	/* not all drives have the same disc_info length, so requeue
1745 	 * packet with the length the drive tells us it can supply
1746 	 */
1747 	cgc.buflen = be16_to_cpu(di->disc_information_length) +
1748 		     sizeof(di->disc_information_length);
1749 
1750 	if (cgc.buflen > sizeof(disc_information))
1751 		cgc.buflen = sizeof(disc_information);
1752 
1753 	cgc.cmd[8] = cgc.buflen;
1754 	return pkt_generic_packet(pd, &cgc);
1755 }
1756 
1757 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1758 {
1759 	struct packet_command cgc;
1760 	int ret;
1761 
1762 	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1763 	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1764 	cgc.cmd[1] = type & 3;
1765 	cgc.cmd[4] = (track & 0xff00) >> 8;
1766 	cgc.cmd[5] = track & 0xff;
1767 	cgc.cmd[8] = 8;
1768 	cgc.quiet = 1;
1769 
1770 	if ((ret = pkt_generic_packet(pd, &cgc)))
1771 		return ret;
1772 
1773 	cgc.buflen = be16_to_cpu(ti->track_information_length) +
1774 		     sizeof(ti->track_information_length);
1775 
1776 	if (cgc.buflen > sizeof(track_information))
1777 		cgc.buflen = sizeof(track_information);
1778 
1779 	cgc.cmd[8] = cgc.buflen;
1780 	return pkt_generic_packet(pd, &cgc);
1781 }
1782 
1783 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1784 						long *last_written)
1785 {
1786 	disc_information di;
1787 	track_information ti;
1788 	__u32 last_track;
1789 	int ret = -1;
1790 
1791 	if ((ret = pkt_get_disc_info(pd, &di)))
1792 		return ret;
1793 
1794 	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1795 	if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1796 		return ret;
1797 
1798 	/* if this track is blank, try the previous. */
1799 	if (ti.blank) {
1800 		last_track--;
1801 		if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1802 			return ret;
1803 	}
1804 
1805 	/* if last recorded field is valid, return it. */
1806 	if (ti.lra_v) {
1807 		*last_written = be32_to_cpu(ti.last_rec_address);
1808 	} else {
1809 		/* make it up instead */
1810 		*last_written = be32_to_cpu(ti.track_start) +
1811 				be32_to_cpu(ti.track_size);
1812 		if (ti.free_blocks)
1813 			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1814 	}
1815 	return 0;
1816 }
1817 
1818 /*
1819  * write mode select package based on pd->settings
1820  */
1821 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1822 {
1823 	struct packet_command cgc;
1824 	struct request_sense sense;
1825 	write_param_page *wp;
1826 	char buffer[128];
1827 	int ret, size;
1828 
1829 	/* doesn't apply to DVD+RW or DVD-RAM */
1830 	if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1831 		return 0;
1832 
1833 	memset(buffer, 0, sizeof(buffer));
1834 	init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1835 	cgc.sense = &sense;
1836 	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1837 		pkt_dump_sense(&cgc);
1838 		return ret;
1839 	}
1840 
1841 	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1842 	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1843 	if (size > sizeof(buffer))
1844 		size = sizeof(buffer);
1845 
1846 	/*
1847 	 * now get it all
1848 	 */
1849 	init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1850 	cgc.sense = &sense;
1851 	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1852 		pkt_dump_sense(&cgc);
1853 		return ret;
1854 	}
1855 
1856 	/*
1857 	 * write page is offset header + block descriptor length
1858 	 */
1859 	wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1860 
1861 	wp->fp = pd->settings.fp;
1862 	wp->track_mode = pd->settings.track_mode;
1863 	wp->write_type = pd->settings.write_type;
1864 	wp->data_block_type = pd->settings.block_mode;
1865 
1866 	wp->multi_session = 0;
1867 
1868 #ifdef PACKET_USE_LS
1869 	wp->link_size = 7;
1870 	wp->ls_v = 1;
1871 #endif
1872 
1873 	if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1874 		wp->session_format = 0;
1875 		wp->subhdr2 = 0x20;
1876 	} else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1877 		wp->session_format = 0x20;
1878 		wp->subhdr2 = 8;
1879 #if 0
1880 		wp->mcn[0] = 0x80;
1881 		memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1882 #endif
1883 	} else {
1884 		/*
1885 		 * paranoia
1886 		 */
1887 		printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1888 		return 1;
1889 	}
1890 	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1891 
1892 	cgc.buflen = cgc.cmd[8] = size;
1893 	if ((ret = pkt_mode_select(pd, &cgc))) {
1894 		pkt_dump_sense(&cgc);
1895 		return ret;
1896 	}
1897 
1898 	pkt_print_settings(pd);
1899 	return 0;
1900 }
1901 
1902 /*
1903  * 1 -- we can write to this track, 0 -- we can't
1904  */
1905 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1906 {
1907 	switch (pd->mmc3_profile) {
1908 		case 0x1a: /* DVD+RW */
1909 		case 0x12: /* DVD-RAM */
1910 			/* The track is always writable on DVD+RW/DVD-RAM */
1911 			return 1;
1912 		default:
1913 			break;
1914 	}
1915 
1916 	if (!ti->packet || !ti->fp)
1917 		return 0;
1918 
1919 	/*
1920 	 * "good" settings as per Mt Fuji.
1921 	 */
1922 	if (ti->rt == 0 && ti->blank == 0)
1923 		return 1;
1924 
1925 	if (ti->rt == 0 && ti->blank == 1)
1926 		return 1;
1927 
1928 	if (ti->rt == 1 && ti->blank == 0)
1929 		return 1;
1930 
1931 	printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1932 	return 0;
1933 }
1934 
1935 /*
1936  * 1 -- we can write to this disc, 0 -- we can't
1937  */
1938 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1939 {
1940 	switch (pd->mmc3_profile) {
1941 		case 0x0a: /* CD-RW */
1942 		case 0xffff: /* MMC3 not supported */
1943 			break;
1944 		case 0x1a: /* DVD+RW */
1945 		case 0x13: /* DVD-RW */
1946 		case 0x12: /* DVD-RAM */
1947 			return 1;
1948 		default:
1949 			VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1950 			return 0;
1951 	}
1952 
1953 	/*
1954 	 * for disc type 0xff we should probably reserve a new track.
1955 	 * but i'm not sure, should we leave this to user apps? probably.
1956 	 */
1957 	if (di->disc_type == 0xff) {
1958 		printk(DRIVER_NAME": Unknown disc. No track?\n");
1959 		return 0;
1960 	}
1961 
1962 	if (di->disc_type != 0x20 && di->disc_type != 0) {
1963 		printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1964 		return 0;
1965 	}
1966 
1967 	if (di->erasable == 0) {
1968 		printk(DRIVER_NAME": Disc not erasable\n");
1969 		return 0;
1970 	}
1971 
1972 	if (di->border_status == PACKET_SESSION_RESERVED) {
1973 		printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1974 		return 0;
1975 	}
1976 
1977 	return 1;
1978 }
1979 
1980 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1981 {
1982 	struct packet_command cgc;
1983 	unsigned char buf[12];
1984 	disc_information di;
1985 	track_information ti;
1986 	int ret, track;
1987 
1988 	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1989 	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1990 	cgc.cmd[8] = 8;
1991 	ret = pkt_generic_packet(pd, &cgc);
1992 	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1993 
1994 	memset(&di, 0, sizeof(disc_information));
1995 	memset(&ti, 0, sizeof(track_information));
1996 
1997 	if ((ret = pkt_get_disc_info(pd, &di))) {
1998 		printk("failed get_disc\n");
1999 		return ret;
2000 	}
2001 
2002 	if (!pkt_writable_disc(pd, &di))
2003 		return -EROFS;
2004 
2005 	pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
2006 
2007 	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
2008 	if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
2009 		printk(DRIVER_NAME": failed get_track\n");
2010 		return ret;
2011 	}
2012 
2013 	if (!pkt_writable_track(pd, &ti)) {
2014 		printk(DRIVER_NAME": can't write to this track\n");
2015 		return -EROFS;
2016 	}
2017 
2018 	/*
2019 	 * we keep packet size in 512 byte units, makes it easier to
2020 	 * deal with request calculations.
2021 	 */
2022 	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
2023 	if (pd->settings.size == 0) {
2024 		printk(DRIVER_NAME": detected zero packet size!\n");
2025 		return -ENXIO;
2026 	}
2027 	if (pd->settings.size > PACKET_MAX_SECTORS) {
2028 		printk(DRIVER_NAME": packet size is too big\n");
2029 		return -EROFS;
2030 	}
2031 	pd->settings.fp = ti.fp;
2032 	pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
2033 
2034 	if (ti.nwa_v) {
2035 		pd->nwa = be32_to_cpu(ti.next_writable);
2036 		set_bit(PACKET_NWA_VALID, &pd->flags);
2037 	}
2038 
2039 	/*
2040 	 * in theory we could use lra on -RW media as well and just zero
2041 	 * blocks that haven't been written yet, but in practice that
2042 	 * is just a no-go. we'll use that for -R, naturally.
2043 	 */
2044 	if (ti.lra_v) {
2045 		pd->lra = be32_to_cpu(ti.last_rec_address);
2046 		set_bit(PACKET_LRA_VALID, &pd->flags);
2047 	} else {
2048 		pd->lra = 0xffffffff;
2049 		set_bit(PACKET_LRA_VALID, &pd->flags);
2050 	}
2051 
2052 	/*
2053 	 * fine for now
2054 	 */
2055 	pd->settings.link_loss = 7;
2056 	pd->settings.write_type = 0;	/* packet */
2057 	pd->settings.track_mode = ti.track_mode;
2058 
2059 	/*
2060 	 * mode1 or mode2 disc
2061 	 */
2062 	switch (ti.data_mode) {
2063 		case PACKET_MODE1:
2064 			pd->settings.block_mode = PACKET_BLOCK_MODE1;
2065 			break;
2066 		case PACKET_MODE2:
2067 			pd->settings.block_mode = PACKET_BLOCK_MODE2;
2068 			break;
2069 		default:
2070 			printk(DRIVER_NAME": unknown data mode\n");
2071 			return -EROFS;
2072 	}
2073 	return 0;
2074 }
2075 
2076 /*
2077  * enable/disable write caching on drive
2078  */
2079 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
2080 						int set)
2081 {
2082 	struct packet_command cgc;
2083 	struct request_sense sense;
2084 	unsigned char buf[64];
2085 	int ret;
2086 
2087 	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
2088 	cgc.sense = &sense;
2089 	cgc.buflen = pd->mode_offset + 12;
2090 
2091 	/*
2092 	 * caching mode page might not be there, so quiet this command
2093 	 */
2094 	cgc.quiet = 1;
2095 
2096 	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
2097 		return ret;
2098 
2099 	buf[pd->mode_offset + 10] |= (!!set << 2);
2100 
2101 	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
2102 	ret = pkt_mode_select(pd, &cgc);
2103 	if (ret) {
2104 		printk(DRIVER_NAME": write caching control failed\n");
2105 		pkt_dump_sense(&cgc);
2106 	} else if (!ret && set)
2107 		printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
2108 	return ret;
2109 }
2110 
2111 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
2112 {
2113 	struct packet_command cgc;
2114 
2115 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2116 	cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
2117 	cgc.cmd[4] = lockflag ? 1 : 0;
2118 	return pkt_generic_packet(pd, &cgc);
2119 }
2120 
2121 /*
2122  * Returns drive maximum write speed
2123  */
2124 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
2125 						unsigned *write_speed)
2126 {
2127 	struct packet_command cgc;
2128 	struct request_sense sense;
2129 	unsigned char buf[256+18];
2130 	unsigned char *cap_buf;
2131 	int ret, offset;
2132 
2133 	cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
2134 	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2135 	cgc.sense = &sense;
2136 
2137 	ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2138 	if (ret) {
2139 		cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2140 			     sizeof(struct mode_page_header);
2141 		ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2142 		if (ret) {
2143 			pkt_dump_sense(&cgc);
2144 			return ret;
2145 		}
2146 	}
2147 
2148 	offset = 20;			    /* Obsoleted field, used by older drives */
2149 	if (cap_buf[1] >= 28)
2150 		offset = 28;		    /* Current write speed selected */
2151 	if (cap_buf[1] >= 30) {
2152 		/* If the drive reports at least one "Logical Unit Write
2153 		 * Speed Performance Descriptor Block", use the information
2154 		 * in the first block. (contains the highest speed)
2155 		 */
2156 		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2157 		if (num_spdb > 0)
2158 			offset = 34;
2159 	}
2160 
2161 	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2162 	return 0;
2163 }
2164 
2165 /* These tables from cdrecord - I don't have orange book */
2166 /* standard speed CD-RW (1-4x) */
2167 static char clv_to_speed[16] = {
2168 	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2169 	   0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2170 };
2171 /* high speed CD-RW (-10x) */
2172 static char hs_clv_to_speed[16] = {
2173 	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2174 	   0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2175 };
2176 /* ultra high speed CD-RW */
2177 static char us_clv_to_speed[16] = {
2178 	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2179 	   0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2180 };
2181 
2182 /*
2183  * reads the maximum media speed from ATIP
2184  */
2185 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2186 						unsigned *speed)
2187 {
2188 	struct packet_command cgc;
2189 	struct request_sense sense;
2190 	unsigned char buf[64];
2191 	unsigned int size, st, sp;
2192 	int ret;
2193 
2194 	init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2195 	cgc.sense = &sense;
2196 	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2197 	cgc.cmd[1] = 2;
2198 	cgc.cmd[2] = 4; /* READ ATIP */
2199 	cgc.cmd[8] = 2;
2200 	ret = pkt_generic_packet(pd, &cgc);
2201 	if (ret) {
2202 		pkt_dump_sense(&cgc);
2203 		return ret;
2204 	}
2205 	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2206 	if (size > sizeof(buf))
2207 		size = sizeof(buf);
2208 
2209 	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2210 	cgc.sense = &sense;
2211 	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2212 	cgc.cmd[1] = 2;
2213 	cgc.cmd[2] = 4;
2214 	cgc.cmd[8] = size;
2215 	ret = pkt_generic_packet(pd, &cgc);
2216 	if (ret) {
2217 		pkt_dump_sense(&cgc);
2218 		return ret;
2219 	}
2220 
2221 	if (!(buf[6] & 0x40)) {
2222 		printk(DRIVER_NAME": Disc type is not CD-RW\n");
2223 		return 1;
2224 	}
2225 	if (!(buf[6] & 0x4)) {
2226 		printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2227 		return 1;
2228 	}
2229 
2230 	st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2231 
2232 	sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2233 
2234 	/* Info from cdrecord */
2235 	switch (st) {
2236 		case 0: /* standard speed */
2237 			*speed = clv_to_speed[sp];
2238 			break;
2239 		case 1: /* high speed */
2240 			*speed = hs_clv_to_speed[sp];
2241 			break;
2242 		case 2: /* ultra high speed */
2243 			*speed = us_clv_to_speed[sp];
2244 			break;
2245 		default:
2246 			printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2247 			return 1;
2248 	}
2249 	if (*speed) {
2250 		printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2251 		return 0;
2252 	} else {
2253 		printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2254 		return 1;
2255 	}
2256 }
2257 
2258 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2259 {
2260 	struct packet_command cgc;
2261 	struct request_sense sense;
2262 	int ret;
2263 
2264 	VPRINTK(DRIVER_NAME": Performing OPC\n");
2265 
2266 	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2267 	cgc.sense = &sense;
2268 	cgc.timeout = 60*HZ;
2269 	cgc.cmd[0] = GPCMD_SEND_OPC;
2270 	cgc.cmd[1] = 1;
2271 	if ((ret = pkt_generic_packet(pd, &cgc)))
2272 		pkt_dump_sense(&cgc);
2273 	return ret;
2274 }
2275 
2276 static int pkt_open_write(struct pktcdvd_device *pd)
2277 {
2278 	int ret;
2279 	unsigned int write_speed, media_write_speed, read_speed;
2280 
2281 	if ((ret = pkt_probe_settings(pd))) {
2282 		VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2283 		return ret;
2284 	}
2285 
2286 	if ((ret = pkt_set_write_settings(pd))) {
2287 		DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2288 		return -EIO;
2289 	}
2290 
2291 	pkt_write_caching(pd, USE_WCACHING);
2292 
2293 	if ((ret = pkt_get_max_speed(pd, &write_speed)))
2294 		write_speed = 16 * 177;
2295 	switch (pd->mmc3_profile) {
2296 		case 0x13: /* DVD-RW */
2297 		case 0x1a: /* DVD+RW */
2298 		case 0x12: /* DVD-RAM */
2299 			DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2300 			break;
2301 		default:
2302 			if ((ret = pkt_media_speed(pd, &media_write_speed)))
2303 				media_write_speed = 16;
2304 			write_speed = min(write_speed, media_write_speed * 177);
2305 			DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2306 			break;
2307 	}
2308 	read_speed = write_speed;
2309 
2310 	if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2311 		DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2312 		return -EIO;
2313 	}
2314 	pd->write_speed = write_speed;
2315 	pd->read_speed = read_speed;
2316 
2317 	if ((ret = pkt_perform_opc(pd))) {
2318 		DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2319 	}
2320 
2321 	return 0;
2322 }
2323 
2324 /*
2325  * called at open time.
2326  */
2327 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2328 {
2329 	int ret;
2330 	long lba;
2331 	struct request_queue *q;
2332 
2333 	/*
2334 	 * We need to re-open the cdrom device without O_NONBLOCK to be able
2335 	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2336 	 * so bdget() can't fail.
2337 	 */
2338 	bdget(pd->bdev->bd_dev);
2339 	if ((ret = blkdev_get(pd->bdev, FMODE_READ)))
2340 		goto out;
2341 
2342 	if ((ret = bd_claim(pd->bdev, pd)))
2343 		goto out_putdev;
2344 
2345 	if ((ret = pkt_get_last_written(pd, &lba))) {
2346 		printk(DRIVER_NAME": pkt_get_last_written failed\n");
2347 		goto out_unclaim;
2348 	}
2349 
2350 	set_capacity(pd->disk, lba << 2);
2351 	set_capacity(pd->bdev->bd_disk, lba << 2);
2352 	bd_set_size(pd->bdev, (loff_t)lba << 11);
2353 
2354 	q = bdev_get_queue(pd->bdev);
2355 	if (write) {
2356 		if ((ret = pkt_open_write(pd)))
2357 			goto out_unclaim;
2358 		/*
2359 		 * Some CDRW drives can not handle writes larger than one packet,
2360 		 * even if the size is a multiple of the packet size.
2361 		 */
2362 		spin_lock_irq(q->queue_lock);
2363 		blk_queue_max_sectors(q, pd->settings.size);
2364 		spin_unlock_irq(q->queue_lock);
2365 		set_bit(PACKET_WRITABLE, &pd->flags);
2366 	} else {
2367 		pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2368 		clear_bit(PACKET_WRITABLE, &pd->flags);
2369 	}
2370 
2371 	if ((ret = pkt_set_segment_merging(pd, q)))
2372 		goto out_unclaim;
2373 
2374 	if (write) {
2375 		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2376 			printk(DRIVER_NAME": not enough memory for buffers\n");
2377 			ret = -ENOMEM;
2378 			goto out_unclaim;
2379 		}
2380 		printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2381 	}
2382 
2383 	return 0;
2384 
2385 out_unclaim:
2386 	bd_release(pd->bdev);
2387 out_putdev:
2388 	blkdev_put(pd->bdev, FMODE_READ);
2389 out:
2390 	return ret;
2391 }
2392 
2393 /*
2394  * called when the device is closed. makes sure that the device flushes
2395  * the internal cache before we close.
2396  */
2397 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2398 {
2399 	if (flush && pkt_flush_cache(pd))
2400 		DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2401 
2402 	pkt_lock_door(pd, 0);
2403 
2404 	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2405 	bd_release(pd->bdev);
2406 	blkdev_put(pd->bdev, FMODE_READ);
2407 
2408 	pkt_shrink_pktlist(pd);
2409 }
2410 
2411 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2412 {
2413 	if (dev_minor >= MAX_WRITERS)
2414 		return NULL;
2415 	return pkt_devs[dev_minor];
2416 }
2417 
2418 static int pkt_open(struct block_device *bdev, fmode_t mode)
2419 {
2420 	struct pktcdvd_device *pd = NULL;
2421 	int ret;
2422 
2423 	VPRINTK(DRIVER_NAME": entering open\n");
2424 
2425 	mutex_lock(&ctl_mutex);
2426 	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2427 	if (!pd) {
2428 		ret = -ENODEV;
2429 		goto out;
2430 	}
2431 	BUG_ON(pd->refcnt < 0);
2432 
2433 	pd->refcnt++;
2434 	if (pd->refcnt > 1) {
2435 		if ((mode & FMODE_WRITE) &&
2436 		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
2437 			ret = -EBUSY;
2438 			goto out_dec;
2439 		}
2440 	} else {
2441 		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2442 		if (ret)
2443 			goto out_dec;
2444 		/*
2445 		 * needed here as well, since ext2 (among others) may change
2446 		 * the blocksize at mount time
2447 		 */
2448 		set_blocksize(bdev, CD_FRAMESIZE);
2449 	}
2450 
2451 	mutex_unlock(&ctl_mutex);
2452 	return 0;
2453 
2454 out_dec:
2455 	pd->refcnt--;
2456 out:
2457 	VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2458 	mutex_unlock(&ctl_mutex);
2459 	return ret;
2460 }
2461 
2462 static int pkt_close(struct gendisk *disk, fmode_t mode)
2463 {
2464 	struct pktcdvd_device *pd = disk->private_data;
2465 	int ret = 0;
2466 
2467 	mutex_lock(&ctl_mutex);
2468 	pd->refcnt--;
2469 	BUG_ON(pd->refcnt < 0);
2470 	if (pd->refcnt == 0) {
2471 		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2472 		pkt_release_dev(pd, flush);
2473 	}
2474 	mutex_unlock(&ctl_mutex);
2475 	return ret;
2476 }
2477 
2478 
2479 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2480 {
2481 	struct packet_stacked_data *psd = bio->bi_private;
2482 	struct pktcdvd_device *pd = psd->pd;
2483 
2484 	bio_put(bio);
2485 	bio_endio(psd->bio, err);
2486 	mempool_free(psd, psd_pool);
2487 	pkt_bio_finished(pd);
2488 }
2489 
2490 static int pkt_make_request(struct request_queue *q, struct bio *bio)
2491 {
2492 	struct pktcdvd_device *pd;
2493 	char b[BDEVNAME_SIZE];
2494 	sector_t zone;
2495 	struct packet_data *pkt;
2496 	int was_empty, blocked_bio;
2497 	struct pkt_rb_node *node;
2498 
2499 	pd = q->queuedata;
2500 	if (!pd) {
2501 		printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2502 		goto end_io;
2503 	}
2504 
2505 	/*
2506 	 * Clone READ bios so we can have our own bi_end_io callback.
2507 	 */
2508 	if (bio_data_dir(bio) == READ) {
2509 		struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2510 		struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2511 
2512 		psd->pd = pd;
2513 		psd->bio = bio;
2514 		cloned_bio->bi_bdev = pd->bdev;
2515 		cloned_bio->bi_private = psd;
2516 		cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2517 		pd->stats.secs_r += bio->bi_size >> 9;
2518 		pkt_queue_bio(pd, cloned_bio);
2519 		return 0;
2520 	}
2521 
2522 	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2523 		printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2524 			pd->name, (unsigned long long)bio->bi_sector);
2525 		goto end_io;
2526 	}
2527 
2528 	if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2529 		printk(DRIVER_NAME": wrong bio size\n");
2530 		goto end_io;
2531 	}
2532 
2533 	blk_queue_bounce(q, &bio);
2534 
2535 	zone = ZONE(bio->bi_sector, pd);
2536 	VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2537 		(unsigned long long)bio->bi_sector,
2538 		(unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2539 
2540 	/* Check if we have to split the bio */
2541 	{
2542 		struct bio_pair *bp;
2543 		sector_t last_zone;
2544 		int first_sectors;
2545 
2546 		last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2547 		if (last_zone != zone) {
2548 			BUG_ON(last_zone != zone + pd->settings.size);
2549 			first_sectors = last_zone - bio->bi_sector;
2550 			bp = bio_split(bio, first_sectors);
2551 			BUG_ON(!bp);
2552 			pkt_make_request(q, &bp->bio1);
2553 			pkt_make_request(q, &bp->bio2);
2554 			bio_pair_release(bp);
2555 			return 0;
2556 		}
2557 	}
2558 
2559 	/*
2560 	 * If we find a matching packet in state WAITING or READ_WAIT, we can
2561 	 * just append this bio to that packet.
2562 	 */
2563 	spin_lock(&pd->cdrw.active_list_lock);
2564 	blocked_bio = 0;
2565 	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2566 		if (pkt->sector == zone) {
2567 			spin_lock(&pkt->lock);
2568 			if ((pkt->state == PACKET_WAITING_STATE) ||
2569 			    (pkt->state == PACKET_READ_WAIT_STATE)) {
2570 				pkt_add_list_last(bio, &pkt->orig_bios,
2571 						  &pkt->orig_bios_tail);
2572 				pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2573 				if ((pkt->write_size >= pkt->frames) &&
2574 				    (pkt->state == PACKET_WAITING_STATE)) {
2575 					atomic_inc(&pkt->run_sm);
2576 					wake_up(&pd->wqueue);
2577 				}
2578 				spin_unlock(&pkt->lock);
2579 				spin_unlock(&pd->cdrw.active_list_lock);
2580 				return 0;
2581 			} else {
2582 				blocked_bio = 1;
2583 			}
2584 			spin_unlock(&pkt->lock);
2585 		}
2586 	}
2587 	spin_unlock(&pd->cdrw.active_list_lock);
2588 
2589  	/*
2590 	 * Test if there is enough room left in the bio work queue
2591 	 * (queue size >= congestion on mark).
2592 	 * If not, wait till the work queue size is below the congestion off mark.
2593 	 */
2594 	spin_lock(&pd->lock);
2595 	if (pd->write_congestion_on > 0
2596 	    && pd->bio_queue_size >= pd->write_congestion_on) {
2597 		set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2598 		do {
2599 			spin_unlock(&pd->lock);
2600 			congestion_wait(BLK_RW_ASYNC, HZ);
2601 			spin_lock(&pd->lock);
2602 		} while(pd->bio_queue_size > pd->write_congestion_off);
2603 	}
2604 	spin_unlock(&pd->lock);
2605 
2606 	/*
2607 	 * No matching packet found. Store the bio in the work queue.
2608 	 */
2609 	node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2610 	node->bio = bio;
2611 	spin_lock(&pd->lock);
2612 	BUG_ON(pd->bio_queue_size < 0);
2613 	was_empty = (pd->bio_queue_size == 0);
2614 	pkt_rbtree_insert(pd, node);
2615 	spin_unlock(&pd->lock);
2616 
2617 	/*
2618 	 * Wake up the worker thread.
2619 	 */
2620 	atomic_set(&pd->scan_queue, 1);
2621 	if (was_empty) {
2622 		/* This wake_up is required for correct operation */
2623 		wake_up(&pd->wqueue);
2624 	} else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2625 		/*
2626 		 * This wake up is not required for correct operation,
2627 		 * but improves performance in some cases.
2628 		 */
2629 		wake_up(&pd->wqueue);
2630 	}
2631 	return 0;
2632 end_io:
2633 	bio_io_error(bio);
2634 	return 0;
2635 }
2636 
2637 
2638 
2639 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2640 			  struct bio_vec *bvec)
2641 {
2642 	struct pktcdvd_device *pd = q->queuedata;
2643 	sector_t zone = ZONE(bmd->bi_sector, pd);
2644 	int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2645 	int remaining = (pd->settings.size << 9) - used;
2646 	int remaining2;
2647 
2648 	/*
2649 	 * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2650 	 * boundary, pkt_make_request() will split the bio.
2651 	 */
2652 	remaining2 = PAGE_SIZE - bmd->bi_size;
2653 	remaining = max(remaining, remaining2);
2654 
2655 	BUG_ON(remaining < 0);
2656 	return remaining;
2657 }
2658 
2659 static void pkt_init_queue(struct pktcdvd_device *pd)
2660 {
2661 	struct request_queue *q = pd->disk->queue;
2662 
2663 	blk_queue_make_request(q, pkt_make_request);
2664 	blk_queue_logical_block_size(q, CD_FRAMESIZE);
2665 	blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2666 	blk_queue_merge_bvec(q, pkt_merge_bvec);
2667 	q->queuedata = pd;
2668 }
2669 
2670 static int pkt_seq_show(struct seq_file *m, void *p)
2671 {
2672 	struct pktcdvd_device *pd = m->private;
2673 	char *msg;
2674 	char bdev_buf[BDEVNAME_SIZE];
2675 	int states[PACKET_NUM_STATES];
2676 
2677 	seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2678 		   bdevname(pd->bdev, bdev_buf));
2679 
2680 	seq_printf(m, "\nSettings:\n");
2681 	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2682 
2683 	if (pd->settings.write_type == 0)
2684 		msg = "Packet";
2685 	else
2686 		msg = "Unknown";
2687 	seq_printf(m, "\twrite type:\t\t%s\n", msg);
2688 
2689 	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2690 	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2691 
2692 	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2693 
2694 	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2695 		msg = "Mode 1";
2696 	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2697 		msg = "Mode 2";
2698 	else
2699 		msg = "Unknown";
2700 	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2701 
2702 	seq_printf(m, "\nStatistics:\n");
2703 	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2704 	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2705 	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2706 	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2707 	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2708 
2709 	seq_printf(m, "\nMisc:\n");
2710 	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2711 	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2712 	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2713 	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2714 	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2715 	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2716 
2717 	seq_printf(m, "\nQueue state:\n");
2718 	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2719 	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2720 	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2721 
2722 	pkt_count_states(pd, states);
2723 	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2724 		   states[0], states[1], states[2], states[3], states[4], states[5]);
2725 
2726 	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2727 			pd->write_congestion_off,
2728 			pd->write_congestion_on);
2729 	return 0;
2730 }
2731 
2732 static int pkt_seq_open(struct inode *inode, struct file *file)
2733 {
2734 	return single_open(file, pkt_seq_show, PDE(inode)->data);
2735 }
2736 
2737 static const struct file_operations pkt_proc_fops = {
2738 	.open	= pkt_seq_open,
2739 	.read	= seq_read,
2740 	.llseek	= seq_lseek,
2741 	.release = single_release
2742 };
2743 
2744 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2745 {
2746 	int i;
2747 	int ret = 0;
2748 	char b[BDEVNAME_SIZE];
2749 	struct block_device *bdev;
2750 
2751 	if (pd->pkt_dev == dev) {
2752 		printk(DRIVER_NAME": Recursive setup not allowed\n");
2753 		return -EBUSY;
2754 	}
2755 	for (i = 0; i < MAX_WRITERS; i++) {
2756 		struct pktcdvd_device *pd2 = pkt_devs[i];
2757 		if (!pd2)
2758 			continue;
2759 		if (pd2->bdev->bd_dev == dev) {
2760 			printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
2761 			return -EBUSY;
2762 		}
2763 		if (pd2->pkt_dev == dev) {
2764 			printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2765 			return -EBUSY;
2766 		}
2767 	}
2768 
2769 	bdev = bdget(dev);
2770 	if (!bdev)
2771 		return -ENOMEM;
2772 	ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY);
2773 	if (ret)
2774 		return ret;
2775 
2776 	/* This is safe, since we have a reference from open(). */
2777 	__module_get(THIS_MODULE);
2778 
2779 	pd->bdev = bdev;
2780 	set_blocksize(bdev, CD_FRAMESIZE);
2781 
2782 	pkt_init_queue(pd);
2783 
2784 	atomic_set(&pd->cdrw.pending_bios, 0);
2785 	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2786 	if (IS_ERR(pd->cdrw.thread)) {
2787 		printk(DRIVER_NAME": can't start kernel thread\n");
2788 		ret = -ENOMEM;
2789 		goto out_mem;
2790 	}
2791 
2792 	proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2793 	DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2794 	return 0;
2795 
2796 out_mem:
2797 	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2798 	/* This is safe: open() is still holding a reference. */
2799 	module_put(THIS_MODULE);
2800 	return ret;
2801 }
2802 
2803 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2804 {
2805 	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2806 
2807 	VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2808 		MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2809 
2810 	switch (cmd) {
2811 	case CDROMEJECT:
2812 		/*
2813 		 * The door gets locked when the device is opened, so we
2814 		 * have to unlock it or else the eject command fails.
2815 		 */
2816 		if (pd->refcnt == 1)
2817 			pkt_lock_door(pd, 0);
2818 		/* fallthru */
2819 	/*
2820 	 * forward selected CDROM ioctls to CD-ROM, for UDF
2821 	 */
2822 	case CDROMMULTISESSION:
2823 	case CDROMREADTOCENTRY:
2824 	case CDROM_LAST_WRITTEN:
2825 	case CDROM_SEND_PACKET:
2826 	case SCSI_IOCTL_SEND_COMMAND:
2827 		return __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2828 
2829 	default:
2830 		VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2831 		return -ENOTTY;
2832 	}
2833 
2834 	return 0;
2835 }
2836 
2837 static int pkt_media_changed(struct gendisk *disk)
2838 {
2839 	struct pktcdvd_device *pd = disk->private_data;
2840 	struct gendisk *attached_disk;
2841 
2842 	if (!pd)
2843 		return 0;
2844 	if (!pd->bdev)
2845 		return 0;
2846 	attached_disk = pd->bdev->bd_disk;
2847 	if (!attached_disk)
2848 		return 0;
2849 	return attached_disk->fops->media_changed(attached_disk);
2850 }
2851 
2852 static const struct block_device_operations pktcdvd_ops = {
2853 	.owner =		THIS_MODULE,
2854 	.open =			pkt_open,
2855 	.release =		pkt_close,
2856 	.locked_ioctl =		pkt_ioctl,
2857 	.media_changed =	pkt_media_changed,
2858 };
2859 
2860 static char *pktcdvd_devnode(struct gendisk *gd, mode_t *mode)
2861 {
2862 	return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2863 }
2864 
2865 /*
2866  * Set up mapping from pktcdvd device to CD-ROM device.
2867  */
2868 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2869 {
2870 	int idx;
2871 	int ret = -ENOMEM;
2872 	struct pktcdvd_device *pd;
2873 	struct gendisk *disk;
2874 
2875 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2876 
2877 	for (idx = 0; idx < MAX_WRITERS; idx++)
2878 		if (!pkt_devs[idx])
2879 			break;
2880 	if (idx == MAX_WRITERS) {
2881 		printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2882 		ret = -EBUSY;
2883 		goto out_mutex;
2884 	}
2885 
2886 	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2887 	if (!pd)
2888 		goto out_mutex;
2889 
2890 	pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2891 						  sizeof(struct pkt_rb_node));
2892 	if (!pd->rb_pool)
2893 		goto out_mem;
2894 
2895 	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2896 	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2897 	spin_lock_init(&pd->cdrw.active_list_lock);
2898 
2899 	spin_lock_init(&pd->lock);
2900 	spin_lock_init(&pd->iosched.lock);
2901 	sprintf(pd->name, DRIVER_NAME"%d", idx);
2902 	init_waitqueue_head(&pd->wqueue);
2903 	pd->bio_queue = RB_ROOT;
2904 
2905 	pd->write_congestion_on  = write_congestion_on;
2906 	pd->write_congestion_off = write_congestion_off;
2907 
2908 	disk = alloc_disk(1);
2909 	if (!disk)
2910 		goto out_mem;
2911 	pd->disk = disk;
2912 	disk->major = pktdev_major;
2913 	disk->first_minor = idx;
2914 	disk->fops = &pktcdvd_ops;
2915 	disk->flags = GENHD_FL_REMOVABLE;
2916 	strcpy(disk->disk_name, pd->name);
2917 	disk->devnode = pktcdvd_devnode;
2918 	disk->private_data = pd;
2919 	disk->queue = blk_alloc_queue(GFP_KERNEL);
2920 	if (!disk->queue)
2921 		goto out_mem2;
2922 
2923 	pd->pkt_dev = MKDEV(pktdev_major, idx);
2924 	ret = pkt_new_dev(pd, dev);
2925 	if (ret)
2926 		goto out_new_dev;
2927 
2928 	add_disk(disk);
2929 
2930 	pkt_sysfs_dev_new(pd);
2931 	pkt_debugfs_dev_new(pd);
2932 
2933 	pkt_devs[idx] = pd;
2934 	if (pkt_dev)
2935 		*pkt_dev = pd->pkt_dev;
2936 
2937 	mutex_unlock(&ctl_mutex);
2938 	return 0;
2939 
2940 out_new_dev:
2941 	blk_cleanup_queue(disk->queue);
2942 out_mem2:
2943 	put_disk(disk);
2944 out_mem:
2945 	if (pd->rb_pool)
2946 		mempool_destroy(pd->rb_pool);
2947 	kfree(pd);
2948 out_mutex:
2949 	mutex_unlock(&ctl_mutex);
2950 	printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2951 	return ret;
2952 }
2953 
2954 /*
2955  * Tear down mapping from pktcdvd device to CD-ROM device.
2956  */
2957 static int pkt_remove_dev(dev_t pkt_dev)
2958 {
2959 	struct pktcdvd_device *pd;
2960 	int idx;
2961 	int ret = 0;
2962 
2963 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2964 
2965 	for (idx = 0; idx < MAX_WRITERS; idx++) {
2966 		pd = pkt_devs[idx];
2967 		if (pd && (pd->pkt_dev == pkt_dev))
2968 			break;
2969 	}
2970 	if (idx == MAX_WRITERS) {
2971 		DPRINTK(DRIVER_NAME": dev not setup\n");
2972 		ret = -ENXIO;
2973 		goto out;
2974 	}
2975 
2976 	if (pd->refcnt > 0) {
2977 		ret = -EBUSY;
2978 		goto out;
2979 	}
2980 	if (!IS_ERR(pd->cdrw.thread))
2981 		kthread_stop(pd->cdrw.thread);
2982 
2983 	pkt_devs[idx] = NULL;
2984 
2985 	pkt_debugfs_dev_remove(pd);
2986 	pkt_sysfs_dev_remove(pd);
2987 
2988 	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2989 
2990 	remove_proc_entry(pd->name, pkt_proc);
2991 	DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2992 
2993 	del_gendisk(pd->disk);
2994 	blk_cleanup_queue(pd->disk->queue);
2995 	put_disk(pd->disk);
2996 
2997 	mempool_destroy(pd->rb_pool);
2998 	kfree(pd);
2999 
3000 	/* This is safe: open() is still holding a reference. */
3001 	module_put(THIS_MODULE);
3002 
3003 out:
3004 	mutex_unlock(&ctl_mutex);
3005 	return ret;
3006 }
3007 
3008 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
3009 {
3010 	struct pktcdvd_device *pd;
3011 
3012 	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
3013 
3014 	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
3015 	if (pd) {
3016 		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
3017 		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
3018 	} else {
3019 		ctrl_cmd->dev = 0;
3020 		ctrl_cmd->pkt_dev = 0;
3021 	}
3022 	ctrl_cmd->num_devices = MAX_WRITERS;
3023 
3024 	mutex_unlock(&ctl_mutex);
3025 }
3026 
3027 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
3028 {
3029 	void __user *argp = (void __user *)arg;
3030 	struct pkt_ctrl_command ctrl_cmd;
3031 	int ret = 0;
3032 	dev_t pkt_dev = 0;
3033 
3034 	if (cmd != PACKET_CTRL_CMD)
3035 		return -ENOTTY;
3036 
3037 	if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
3038 		return -EFAULT;
3039 
3040 	switch (ctrl_cmd.command) {
3041 	case PKT_CTRL_CMD_SETUP:
3042 		if (!capable(CAP_SYS_ADMIN))
3043 			return -EPERM;
3044 		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
3045 		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
3046 		break;
3047 	case PKT_CTRL_CMD_TEARDOWN:
3048 		if (!capable(CAP_SYS_ADMIN))
3049 			return -EPERM;
3050 		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
3051 		break;
3052 	case PKT_CTRL_CMD_STATUS:
3053 		pkt_get_status(&ctrl_cmd);
3054 		break;
3055 	default:
3056 		return -ENOTTY;
3057 	}
3058 
3059 	if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
3060 		return -EFAULT;
3061 	return ret;
3062 }
3063 
3064 
3065 static const struct file_operations pkt_ctl_fops = {
3066 	.ioctl	 = pkt_ctl_ioctl,
3067 	.owner	 = THIS_MODULE,
3068 };
3069 
3070 static struct miscdevice pkt_misc = {
3071 	.minor 		= MISC_DYNAMIC_MINOR,
3072 	.name  		= DRIVER_NAME,
3073 	.nodename	= "pktcdvd/control",
3074 	.fops  		= &pkt_ctl_fops
3075 };
3076 
3077 static int __init pkt_init(void)
3078 {
3079 	int ret;
3080 
3081 	mutex_init(&ctl_mutex);
3082 
3083 	psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
3084 					sizeof(struct packet_stacked_data));
3085 	if (!psd_pool)
3086 		return -ENOMEM;
3087 
3088 	ret = register_blkdev(pktdev_major, DRIVER_NAME);
3089 	if (ret < 0) {
3090 		printk(DRIVER_NAME": Unable to register block device\n");
3091 		goto out2;
3092 	}
3093 	if (!pktdev_major)
3094 		pktdev_major = ret;
3095 
3096 	ret = pkt_sysfs_init();
3097 	if (ret)
3098 		goto out;
3099 
3100 	pkt_debugfs_init();
3101 
3102 	ret = misc_register(&pkt_misc);
3103 	if (ret) {
3104 		printk(DRIVER_NAME": Unable to register misc device\n");
3105 		goto out_misc;
3106 	}
3107 
3108 	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
3109 
3110 	return 0;
3111 
3112 out_misc:
3113 	pkt_debugfs_cleanup();
3114 	pkt_sysfs_cleanup();
3115 out:
3116 	unregister_blkdev(pktdev_major, DRIVER_NAME);
3117 out2:
3118 	mempool_destroy(psd_pool);
3119 	return ret;
3120 }
3121 
3122 static void __exit pkt_exit(void)
3123 {
3124 	remove_proc_entry("driver/"DRIVER_NAME, NULL);
3125 	misc_deregister(&pkt_misc);
3126 
3127 	pkt_debugfs_cleanup();
3128 	pkt_sysfs_cleanup();
3129 
3130 	unregister_blkdev(pktdev_major, DRIVER_NAME);
3131 	mempool_destroy(psd_pool);
3132 }
3133 
3134 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3135 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3136 MODULE_LICENSE("GPL");
3137 
3138 module_init(pkt_init);
3139 module_exit(pkt_exit);
3140