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 * such as drivers/scsi/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 ->submit_bio function that forwards
40 * read requests directly to the iosched queue and puts write requests in the
41 * unaligned write queue. A kernel thread performs the necessary read
42 * gathering to convert the unaligned writes to aligned writes and then feeds
43 * them to the packet I/O scheduler.
44 *
45 *************************************************************************/
46
47 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
48
49 #include <linux/backing-dev.h>
50 #include <linux/compat.h>
51 #include <linux/debugfs.h>
52 #include <linux/device.h>
53 #include <linux/errno.h>
54 #include <linux/file.h>
55 #include <linux/freezer.h>
56 #include <linux/kernel.h>
57 #include <linux/kthread.h>
58 #include <linux/miscdevice.h>
59 #include <linux/module.h>
60 #include <linux/mutex.h>
61 #include <linux/nospec.h>
62 #include <linux/pktcdvd.h>
63 #include <linux/proc_fs.h>
64 #include <linux/seq_file.h>
65 #include <linux/slab.h>
66 #include <linux/spinlock.h>
67 #include <linux/types.h>
68 #include <linux/uaccess.h>
69
70 #include <scsi/scsi.h>
71 #include <scsi/scsi_cmnd.h>
72 #include <scsi/scsi_ioctl.h>
73
74 #include <asm/unaligned.h>
75
76 #define DRIVER_NAME "pktcdvd"
77
78 #define MAX_SPEED 0xffff
79
80 static DEFINE_MUTEX(pktcdvd_mutex);
81 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
82 static struct proc_dir_entry *pkt_proc;
83 static int pktdev_major;
84 static int write_congestion_on = PKT_WRITE_CONGESTION_ON;
85 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
86 static struct mutex ctl_mutex; /* Serialize open/close/setup/teardown */
87 static mempool_t psd_pool;
88 static struct bio_set pkt_bio_set;
89
90 /* /sys/class/pktcdvd */
91 static struct class class_pktcdvd;
92 static struct dentry *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
93
94 /* forward declaration */
95 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
96 static int pkt_remove_dev(dev_t pkt_dev);
97
get_zone(sector_t sector,struct pktcdvd_device * pd)98 static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
99 {
100 return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1);
101 }
102
103 /**********************************************************
104 * sysfs interface for pktcdvd
105 * by (C) 2006 Thomas Maier <balagi@justmail.de>
106
107 /sys/class/pktcdvd/pktcdvd[0-7]/
108 stat/reset
109 stat/packets_started
110 stat/packets_finished
111 stat/kb_written
112 stat/kb_read
113 stat/kb_read_gather
114 write_queue/size
115 write_queue/congestion_off
116 write_queue/congestion_on
117 **********************************************************/
118
packets_started_show(struct device * dev,struct device_attribute * attr,char * buf)119 static ssize_t packets_started_show(struct device *dev,
120 struct device_attribute *attr, char *buf)
121 {
122 struct pktcdvd_device *pd = dev_get_drvdata(dev);
123
124 return sysfs_emit(buf, "%lu\n", pd->stats.pkt_started);
125 }
126 static DEVICE_ATTR_RO(packets_started);
127
packets_finished_show(struct device * dev,struct device_attribute * attr,char * buf)128 static ssize_t packets_finished_show(struct device *dev,
129 struct device_attribute *attr, char *buf)
130 {
131 struct pktcdvd_device *pd = dev_get_drvdata(dev);
132
133 return sysfs_emit(buf, "%lu\n", pd->stats.pkt_ended);
134 }
135 static DEVICE_ATTR_RO(packets_finished);
136
kb_written_show(struct device * dev,struct device_attribute * attr,char * buf)137 static ssize_t kb_written_show(struct device *dev,
138 struct device_attribute *attr, char *buf)
139 {
140 struct pktcdvd_device *pd = dev_get_drvdata(dev);
141
142 return sysfs_emit(buf, "%lu\n", pd->stats.secs_w >> 1);
143 }
144 static DEVICE_ATTR_RO(kb_written);
145
kb_read_show(struct device * dev,struct device_attribute * attr,char * buf)146 static ssize_t kb_read_show(struct device *dev,
147 struct device_attribute *attr, char *buf)
148 {
149 struct pktcdvd_device *pd = dev_get_drvdata(dev);
150
151 return sysfs_emit(buf, "%lu\n", pd->stats.secs_r >> 1);
152 }
153 static DEVICE_ATTR_RO(kb_read);
154
kb_read_gather_show(struct device * dev,struct device_attribute * attr,char * buf)155 static ssize_t kb_read_gather_show(struct device *dev,
156 struct device_attribute *attr, char *buf)
157 {
158 struct pktcdvd_device *pd = dev_get_drvdata(dev);
159
160 return sysfs_emit(buf, "%lu\n", pd->stats.secs_rg >> 1);
161 }
162 static DEVICE_ATTR_RO(kb_read_gather);
163
reset_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)164 static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
165 const char *buf, size_t len)
166 {
167 struct pktcdvd_device *pd = dev_get_drvdata(dev);
168
169 if (len > 0) {
170 pd->stats.pkt_started = 0;
171 pd->stats.pkt_ended = 0;
172 pd->stats.secs_w = 0;
173 pd->stats.secs_rg = 0;
174 pd->stats.secs_r = 0;
175 }
176 return len;
177 }
178 static DEVICE_ATTR_WO(reset);
179
180 static struct attribute *pkt_stat_attrs[] = {
181 &dev_attr_packets_finished.attr,
182 &dev_attr_packets_started.attr,
183 &dev_attr_kb_read.attr,
184 &dev_attr_kb_written.attr,
185 &dev_attr_kb_read_gather.attr,
186 &dev_attr_reset.attr,
187 NULL,
188 };
189
190 static const struct attribute_group pkt_stat_group = {
191 .name = "stat",
192 .attrs = pkt_stat_attrs,
193 };
194
size_show(struct device * dev,struct device_attribute * attr,char * buf)195 static ssize_t size_show(struct device *dev,
196 struct device_attribute *attr, char *buf)
197 {
198 struct pktcdvd_device *pd = dev_get_drvdata(dev);
199 int n;
200
201 spin_lock(&pd->lock);
202 n = sysfs_emit(buf, "%d\n", pd->bio_queue_size);
203 spin_unlock(&pd->lock);
204 return n;
205 }
206 static DEVICE_ATTR_RO(size);
207
init_write_congestion_marks(int * lo,int * hi)208 static void init_write_congestion_marks(int* lo, int* hi)
209 {
210 if (*hi > 0) {
211 *hi = max(*hi, 500);
212 *hi = min(*hi, 1000000);
213 if (*lo <= 0)
214 *lo = *hi - 100;
215 else {
216 *lo = min(*lo, *hi - 100);
217 *lo = max(*lo, 100);
218 }
219 } else {
220 *hi = -1;
221 *lo = -1;
222 }
223 }
224
congestion_off_show(struct device * dev,struct device_attribute * attr,char * buf)225 static ssize_t congestion_off_show(struct device *dev,
226 struct device_attribute *attr, char *buf)
227 {
228 struct pktcdvd_device *pd = dev_get_drvdata(dev);
229 int n;
230
231 spin_lock(&pd->lock);
232 n = sysfs_emit(buf, "%d\n", pd->write_congestion_off);
233 spin_unlock(&pd->lock);
234 return n;
235 }
236
congestion_off_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)237 static ssize_t congestion_off_store(struct device *dev,
238 struct device_attribute *attr,
239 const char *buf, size_t len)
240 {
241 struct pktcdvd_device *pd = dev_get_drvdata(dev);
242 int val, ret;
243
244 ret = kstrtoint(buf, 10, &val);
245 if (ret)
246 return ret;
247
248 spin_lock(&pd->lock);
249 pd->write_congestion_off = val;
250 init_write_congestion_marks(&pd->write_congestion_off, &pd->write_congestion_on);
251 spin_unlock(&pd->lock);
252 return len;
253 }
254 static DEVICE_ATTR_RW(congestion_off);
255
congestion_on_show(struct device * dev,struct device_attribute * attr,char * buf)256 static ssize_t congestion_on_show(struct device *dev,
257 struct device_attribute *attr, char *buf)
258 {
259 struct pktcdvd_device *pd = dev_get_drvdata(dev);
260 int n;
261
262 spin_lock(&pd->lock);
263 n = sysfs_emit(buf, "%d\n", pd->write_congestion_on);
264 spin_unlock(&pd->lock);
265 return n;
266 }
267
congestion_on_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t len)268 static ssize_t congestion_on_store(struct device *dev,
269 struct device_attribute *attr,
270 const char *buf, size_t len)
271 {
272 struct pktcdvd_device *pd = dev_get_drvdata(dev);
273 int val, ret;
274
275 ret = kstrtoint(buf, 10, &val);
276 if (ret)
277 return ret;
278
279 spin_lock(&pd->lock);
280 pd->write_congestion_on = val;
281 init_write_congestion_marks(&pd->write_congestion_off, &pd->write_congestion_on);
282 spin_unlock(&pd->lock);
283 return len;
284 }
285 static DEVICE_ATTR_RW(congestion_on);
286
287 static struct attribute *pkt_wq_attrs[] = {
288 &dev_attr_congestion_on.attr,
289 &dev_attr_congestion_off.attr,
290 &dev_attr_size.attr,
291 NULL,
292 };
293
294 static const struct attribute_group pkt_wq_group = {
295 .name = "write_queue",
296 .attrs = pkt_wq_attrs,
297 };
298
299 static const struct attribute_group *pkt_groups[] = {
300 &pkt_stat_group,
301 &pkt_wq_group,
302 NULL,
303 };
304
pkt_sysfs_dev_new(struct pktcdvd_device * pd)305 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
306 {
307 if (class_is_registered(&class_pktcdvd)) {
308 pd->dev = device_create_with_groups(&class_pktcdvd, NULL,
309 MKDEV(0, 0), pd, pkt_groups,
310 "%s", pd->disk->disk_name);
311 if (IS_ERR(pd->dev))
312 pd->dev = NULL;
313 }
314 }
315
pkt_sysfs_dev_remove(struct pktcdvd_device * pd)316 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
317 {
318 if (class_is_registered(&class_pktcdvd))
319 device_unregister(pd->dev);
320 }
321
322
323 /********************************************************************
324 /sys/class/pktcdvd/
325 add map block device
326 remove unmap packet dev
327 device_map show mappings
328 *******************************************************************/
329
device_map_show(const struct class * c,const struct class_attribute * attr,char * data)330 static ssize_t device_map_show(const struct class *c, const struct class_attribute *attr,
331 char *data)
332 {
333 int n = 0;
334 int idx;
335 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
336 for (idx = 0; idx < MAX_WRITERS; idx++) {
337 struct pktcdvd_device *pd = pkt_devs[idx];
338 if (!pd)
339 continue;
340 n += sysfs_emit_at(data, n, "%s %u:%u %u:%u\n",
341 pd->disk->disk_name,
342 MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
343 MAJOR(pd->bdev->bd_dev),
344 MINOR(pd->bdev->bd_dev));
345 }
346 mutex_unlock(&ctl_mutex);
347 return n;
348 }
349 static CLASS_ATTR_RO(device_map);
350
add_store(const struct class * c,const struct class_attribute * attr,const char * buf,size_t count)351 static ssize_t add_store(const struct class *c, const struct class_attribute *attr,
352 const char *buf, size_t count)
353 {
354 unsigned int major, minor;
355
356 if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
357 /* pkt_setup_dev() expects caller to hold reference to self */
358 if (!try_module_get(THIS_MODULE))
359 return -ENODEV;
360
361 pkt_setup_dev(MKDEV(major, minor), NULL);
362
363 module_put(THIS_MODULE);
364
365 return count;
366 }
367
368 return -EINVAL;
369 }
370 static CLASS_ATTR_WO(add);
371
remove_store(const struct class * c,const struct class_attribute * attr,const char * buf,size_t count)372 static ssize_t remove_store(const struct class *c, const struct class_attribute *attr,
373 const char *buf, size_t count)
374 {
375 unsigned int major, minor;
376 if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
377 pkt_remove_dev(MKDEV(major, minor));
378 return count;
379 }
380 return -EINVAL;
381 }
382 static CLASS_ATTR_WO(remove);
383
384 static struct attribute *class_pktcdvd_attrs[] = {
385 &class_attr_add.attr,
386 &class_attr_remove.attr,
387 &class_attr_device_map.attr,
388 NULL,
389 };
390 ATTRIBUTE_GROUPS(class_pktcdvd);
391
392 static struct class class_pktcdvd = {
393 .name = DRIVER_NAME,
394 .class_groups = class_pktcdvd_groups,
395 };
396
pkt_sysfs_init(void)397 static int pkt_sysfs_init(void)
398 {
399 /*
400 * create control files in sysfs
401 * /sys/class/pktcdvd/...
402 */
403 return class_register(&class_pktcdvd);
404 }
405
pkt_sysfs_cleanup(void)406 static void pkt_sysfs_cleanup(void)
407 {
408 class_unregister(&class_pktcdvd);
409 }
410
411 /********************************************************************
412 entries in debugfs
413
414 /sys/kernel/debug/pktcdvd[0-7]/
415 info
416
417 *******************************************************************/
418
pkt_count_states(struct pktcdvd_device * pd,int * states)419 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
420 {
421 struct packet_data *pkt;
422 int i;
423
424 for (i = 0; i < PACKET_NUM_STATES; i++)
425 states[i] = 0;
426
427 spin_lock(&pd->cdrw.active_list_lock);
428 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
429 states[pkt->state]++;
430 }
431 spin_unlock(&pd->cdrw.active_list_lock);
432 }
433
pkt_seq_show(struct seq_file * m,void * p)434 static int pkt_seq_show(struct seq_file *m, void *p)
435 {
436 struct pktcdvd_device *pd = m->private;
437 char *msg;
438 int states[PACKET_NUM_STATES];
439
440 seq_printf(m, "Writer %s mapped to %pg:\n", pd->disk->disk_name, pd->bdev);
441
442 seq_printf(m, "\nSettings:\n");
443 seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
444
445 if (pd->settings.write_type == 0)
446 msg = "Packet";
447 else
448 msg = "Unknown";
449 seq_printf(m, "\twrite type:\t\t%s\n", msg);
450
451 seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
452 seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
453
454 seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
455
456 if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
457 msg = "Mode 1";
458 else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
459 msg = "Mode 2";
460 else
461 msg = "Unknown";
462 seq_printf(m, "\tblock mode:\t\t%s\n", msg);
463
464 seq_printf(m, "\nStatistics:\n");
465 seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
466 seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
467 seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
468 seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
469 seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
470
471 seq_printf(m, "\nMisc:\n");
472 seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
473 seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
474 seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
475 seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
476 seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
477 seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
478
479 seq_printf(m, "\nQueue state:\n");
480 seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
481 seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
482 seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", pd->current_sector);
483
484 pkt_count_states(pd, states);
485 seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
486 states[0], states[1], states[2], states[3], states[4], states[5]);
487
488 seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
489 pd->write_congestion_off,
490 pd->write_congestion_on);
491 return 0;
492 }
493 DEFINE_SHOW_ATTRIBUTE(pkt_seq);
494
pkt_debugfs_dev_new(struct pktcdvd_device * pd)495 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
496 {
497 if (!pkt_debugfs_root)
498 return;
499 pd->dfs_d_root = debugfs_create_dir(pd->disk->disk_name, pkt_debugfs_root);
500 if (!pd->dfs_d_root)
501 return;
502
503 pd->dfs_f_info = debugfs_create_file("info", 0444, pd->dfs_d_root,
504 pd, &pkt_seq_fops);
505 }
506
pkt_debugfs_dev_remove(struct pktcdvd_device * pd)507 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
508 {
509 if (!pkt_debugfs_root)
510 return;
511 debugfs_remove(pd->dfs_f_info);
512 debugfs_remove(pd->dfs_d_root);
513 pd->dfs_f_info = NULL;
514 pd->dfs_d_root = NULL;
515 }
516
pkt_debugfs_init(void)517 static void pkt_debugfs_init(void)
518 {
519 pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
520 }
521
pkt_debugfs_cleanup(void)522 static void pkt_debugfs_cleanup(void)
523 {
524 debugfs_remove(pkt_debugfs_root);
525 pkt_debugfs_root = NULL;
526 }
527
528 /* ----------------------------------------------------------*/
529
530
pkt_bio_finished(struct pktcdvd_device * pd)531 static void pkt_bio_finished(struct pktcdvd_device *pd)
532 {
533 struct device *ddev = disk_to_dev(pd->disk);
534
535 BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
536 if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
537 dev_dbg(ddev, "queue empty\n");
538 atomic_set(&pd->iosched.attention, 1);
539 wake_up(&pd->wqueue);
540 }
541 }
542
543 /*
544 * Allocate a packet_data struct
545 */
pkt_alloc_packet_data(int frames)546 static struct packet_data *pkt_alloc_packet_data(int frames)
547 {
548 int i;
549 struct packet_data *pkt;
550
551 pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
552 if (!pkt)
553 goto no_pkt;
554
555 pkt->frames = frames;
556 pkt->w_bio = bio_kmalloc(frames, GFP_KERNEL);
557 if (!pkt->w_bio)
558 goto no_bio;
559
560 for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
561 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
562 if (!pkt->pages[i])
563 goto no_page;
564 }
565
566 spin_lock_init(&pkt->lock);
567 bio_list_init(&pkt->orig_bios);
568
569 for (i = 0; i < frames; i++) {
570 pkt->r_bios[i] = bio_kmalloc(1, GFP_KERNEL);
571 if (!pkt->r_bios[i])
572 goto no_rd_bio;
573 }
574
575 return pkt;
576
577 no_rd_bio:
578 for (i = 0; i < frames; i++)
579 kfree(pkt->r_bios[i]);
580 no_page:
581 for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
582 if (pkt->pages[i])
583 __free_page(pkt->pages[i]);
584 kfree(pkt->w_bio);
585 no_bio:
586 kfree(pkt);
587 no_pkt:
588 return NULL;
589 }
590
591 /*
592 * Free a packet_data struct
593 */
pkt_free_packet_data(struct packet_data * pkt)594 static void pkt_free_packet_data(struct packet_data *pkt)
595 {
596 int i;
597
598 for (i = 0; i < pkt->frames; i++)
599 kfree(pkt->r_bios[i]);
600 for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
601 __free_page(pkt->pages[i]);
602 kfree(pkt->w_bio);
603 kfree(pkt);
604 }
605
pkt_shrink_pktlist(struct pktcdvd_device * pd)606 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
607 {
608 struct packet_data *pkt, *next;
609
610 BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
611
612 list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
613 pkt_free_packet_data(pkt);
614 }
615 INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
616 }
617
pkt_grow_pktlist(struct pktcdvd_device * pd,int nr_packets)618 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
619 {
620 struct packet_data *pkt;
621
622 BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
623
624 while (nr_packets > 0) {
625 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
626 if (!pkt) {
627 pkt_shrink_pktlist(pd);
628 return 0;
629 }
630 pkt->id = nr_packets;
631 pkt->pd = pd;
632 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
633 nr_packets--;
634 }
635 return 1;
636 }
637
pkt_rbtree_next(struct pkt_rb_node * node)638 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
639 {
640 struct rb_node *n = rb_next(&node->rb_node);
641 if (!n)
642 return NULL;
643 return rb_entry(n, struct pkt_rb_node, rb_node);
644 }
645
pkt_rbtree_erase(struct pktcdvd_device * pd,struct pkt_rb_node * node)646 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
647 {
648 rb_erase(&node->rb_node, &pd->bio_queue);
649 mempool_free(node, &pd->rb_pool);
650 pd->bio_queue_size--;
651 BUG_ON(pd->bio_queue_size < 0);
652 }
653
654 /*
655 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
656 */
pkt_rbtree_find(struct pktcdvd_device * pd,sector_t s)657 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
658 {
659 struct rb_node *n = pd->bio_queue.rb_node;
660 struct rb_node *next;
661 struct pkt_rb_node *tmp;
662
663 if (!n) {
664 BUG_ON(pd->bio_queue_size > 0);
665 return NULL;
666 }
667
668 for (;;) {
669 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
670 if (s <= tmp->bio->bi_iter.bi_sector)
671 next = n->rb_left;
672 else
673 next = n->rb_right;
674 if (!next)
675 break;
676 n = next;
677 }
678
679 if (s > tmp->bio->bi_iter.bi_sector) {
680 tmp = pkt_rbtree_next(tmp);
681 if (!tmp)
682 return NULL;
683 }
684 BUG_ON(s > tmp->bio->bi_iter.bi_sector);
685 return tmp;
686 }
687
688 /*
689 * Insert a node into the pd->bio_queue rb tree.
690 */
pkt_rbtree_insert(struct pktcdvd_device * pd,struct pkt_rb_node * node)691 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
692 {
693 struct rb_node **p = &pd->bio_queue.rb_node;
694 struct rb_node *parent = NULL;
695 sector_t s = node->bio->bi_iter.bi_sector;
696 struct pkt_rb_node *tmp;
697
698 while (*p) {
699 parent = *p;
700 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
701 if (s < tmp->bio->bi_iter.bi_sector)
702 p = &(*p)->rb_left;
703 else
704 p = &(*p)->rb_right;
705 }
706 rb_link_node(&node->rb_node, parent, p);
707 rb_insert_color(&node->rb_node, &pd->bio_queue);
708 pd->bio_queue_size++;
709 }
710
711 /*
712 * Send a packet_command to the underlying block device and
713 * wait for completion.
714 */
pkt_generic_packet(struct pktcdvd_device * pd,struct packet_command * cgc)715 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
716 {
717 struct request_queue *q = bdev_get_queue(pd->bdev);
718 struct scsi_cmnd *scmd;
719 struct request *rq;
720 int ret = 0;
721
722 rq = scsi_alloc_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
723 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
724 if (IS_ERR(rq))
725 return PTR_ERR(rq);
726 scmd = blk_mq_rq_to_pdu(rq);
727
728 if (cgc->buflen) {
729 ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
730 GFP_NOIO);
731 if (ret)
732 goto out;
733 }
734
735 scmd->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
736 memcpy(scmd->cmnd, cgc->cmd, CDROM_PACKET_SIZE);
737
738 rq->timeout = 60*HZ;
739 if (cgc->quiet)
740 rq->rq_flags |= RQF_QUIET;
741
742 blk_execute_rq(rq, false);
743 if (scmd->result)
744 ret = -EIO;
745 out:
746 blk_mq_free_request(rq);
747 return ret;
748 }
749
sense_key_string(__u8 index)750 static const char *sense_key_string(__u8 index)
751 {
752 static const char * const info[] = {
753 "No sense", "Recovered error", "Not ready",
754 "Medium error", "Hardware error", "Illegal request",
755 "Unit attention", "Data protect", "Blank check",
756 };
757
758 return index < ARRAY_SIZE(info) ? info[index] : "INVALID";
759 }
760
761 /*
762 * A generic sense dump / resolve mechanism should be implemented across
763 * all ATAPI + SCSI devices.
764 */
pkt_dump_sense(struct pktcdvd_device * pd,struct packet_command * cgc)765 static void pkt_dump_sense(struct pktcdvd_device *pd,
766 struct packet_command *cgc)
767 {
768 struct device *ddev = disk_to_dev(pd->disk);
769 struct scsi_sense_hdr *sshdr = cgc->sshdr;
770
771 if (sshdr)
772 dev_err(ddev, "%*ph - sense %02x.%02x.%02x (%s)\n",
773 CDROM_PACKET_SIZE, cgc->cmd,
774 sshdr->sense_key, sshdr->asc, sshdr->ascq,
775 sense_key_string(sshdr->sense_key));
776 else
777 dev_err(ddev, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
778 }
779
780 /*
781 * flush the drive cache to media
782 */
pkt_flush_cache(struct pktcdvd_device * pd)783 static int pkt_flush_cache(struct pktcdvd_device *pd)
784 {
785 struct packet_command cgc;
786
787 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
788 cgc.cmd[0] = GPCMD_FLUSH_CACHE;
789 cgc.quiet = 1;
790
791 /*
792 * the IMMED bit -- we default to not setting it, although that
793 * would allow a much faster close, this is safer
794 */
795 #if 0
796 cgc.cmd[1] = 1 << 1;
797 #endif
798 return pkt_generic_packet(pd, &cgc);
799 }
800
801 /*
802 * speed is given as the normal factor, e.g. 4 for 4x
803 */
pkt_set_speed(struct pktcdvd_device * pd,unsigned write_speed,unsigned read_speed)804 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
805 unsigned write_speed, unsigned read_speed)
806 {
807 struct packet_command cgc;
808 struct scsi_sense_hdr sshdr;
809 int ret;
810
811 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
812 cgc.sshdr = &sshdr;
813 cgc.cmd[0] = GPCMD_SET_SPEED;
814 put_unaligned_be16(read_speed, &cgc.cmd[2]);
815 put_unaligned_be16(write_speed, &cgc.cmd[4]);
816
817 ret = pkt_generic_packet(pd, &cgc);
818 if (ret)
819 pkt_dump_sense(pd, &cgc);
820
821 return ret;
822 }
823
824 /*
825 * Queue a bio for processing by the low-level CD device. Must be called
826 * from process context.
827 */
pkt_queue_bio(struct pktcdvd_device * pd,struct bio * bio)828 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
829 {
830 spin_lock(&pd->iosched.lock);
831 if (bio_data_dir(bio) == READ)
832 bio_list_add(&pd->iosched.read_queue, bio);
833 else
834 bio_list_add(&pd->iosched.write_queue, bio);
835 spin_unlock(&pd->iosched.lock);
836
837 atomic_set(&pd->iosched.attention, 1);
838 wake_up(&pd->wqueue);
839 }
840
841 /*
842 * Process the queued read/write requests. This function handles special
843 * requirements for CDRW drives:
844 * - A cache flush command must be inserted before a read request if the
845 * previous request was a write.
846 * - Switching between reading and writing is slow, so don't do it more often
847 * than necessary.
848 * - Optimize for throughput at the expense of latency. This means that streaming
849 * writes will never be interrupted by a read, but if the drive has to seek
850 * before the next write, switch to reading instead if there are any pending
851 * read requests.
852 * - Set the read speed according to current usage pattern. When only reading
853 * from the device, it's best to use the highest possible read speed, but
854 * when switching often between reading and writing, it's better to have the
855 * same read and write speeds.
856 */
pkt_iosched_process_queue(struct pktcdvd_device * pd)857 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
858 {
859 struct device *ddev = disk_to_dev(pd->disk);
860
861 if (atomic_read(&pd->iosched.attention) == 0)
862 return;
863 atomic_set(&pd->iosched.attention, 0);
864
865 for (;;) {
866 struct bio *bio;
867 int reads_queued, writes_queued;
868
869 spin_lock(&pd->iosched.lock);
870 reads_queued = !bio_list_empty(&pd->iosched.read_queue);
871 writes_queued = !bio_list_empty(&pd->iosched.write_queue);
872 spin_unlock(&pd->iosched.lock);
873
874 if (!reads_queued && !writes_queued)
875 break;
876
877 if (pd->iosched.writing) {
878 int need_write_seek = 1;
879 spin_lock(&pd->iosched.lock);
880 bio = bio_list_peek(&pd->iosched.write_queue);
881 spin_unlock(&pd->iosched.lock);
882 if (bio && (bio->bi_iter.bi_sector ==
883 pd->iosched.last_write))
884 need_write_seek = 0;
885 if (need_write_seek && reads_queued) {
886 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
887 dev_dbg(ddev, "write, waiting\n");
888 break;
889 }
890 pkt_flush_cache(pd);
891 pd->iosched.writing = 0;
892 }
893 } else {
894 if (!reads_queued && writes_queued) {
895 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
896 dev_dbg(ddev, "read, waiting\n");
897 break;
898 }
899 pd->iosched.writing = 1;
900 }
901 }
902
903 spin_lock(&pd->iosched.lock);
904 if (pd->iosched.writing)
905 bio = bio_list_pop(&pd->iosched.write_queue);
906 else
907 bio = bio_list_pop(&pd->iosched.read_queue);
908 spin_unlock(&pd->iosched.lock);
909
910 if (!bio)
911 continue;
912
913 if (bio_data_dir(bio) == READ)
914 pd->iosched.successive_reads +=
915 bio->bi_iter.bi_size >> 10;
916 else {
917 pd->iosched.successive_reads = 0;
918 pd->iosched.last_write = bio_end_sector(bio);
919 }
920 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
921 if (pd->read_speed == pd->write_speed) {
922 pd->read_speed = MAX_SPEED;
923 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
924 }
925 } else {
926 if (pd->read_speed != pd->write_speed) {
927 pd->read_speed = pd->write_speed;
928 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
929 }
930 }
931
932 atomic_inc(&pd->cdrw.pending_bios);
933 submit_bio_noacct(bio);
934 }
935 }
936
937 /*
938 * Special care is needed if the underlying block device has a small
939 * max_phys_segments value.
940 */
pkt_set_segment_merging(struct pktcdvd_device * pd,struct request_queue * q)941 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
942 {
943 struct device *ddev = disk_to_dev(pd->disk);
944
945 if ((pd->settings.size << 9) / CD_FRAMESIZE <= queue_max_segments(q)) {
946 /*
947 * The cdrom device can handle one segment/frame
948 */
949 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
950 return 0;
951 }
952
953 if ((pd->settings.size << 9) / PAGE_SIZE <= queue_max_segments(q)) {
954 /*
955 * We can handle this case at the expense of some extra memory
956 * copies during write operations
957 */
958 set_bit(PACKET_MERGE_SEGS, &pd->flags);
959 return 0;
960 }
961
962 dev_err(ddev, "cdrom max_phys_segments too small\n");
963 return -EIO;
964 }
965
pkt_end_io_read(struct bio * bio)966 static void pkt_end_io_read(struct bio *bio)
967 {
968 struct packet_data *pkt = bio->bi_private;
969 struct pktcdvd_device *pd = pkt->pd;
970 BUG_ON(!pd);
971
972 dev_dbg(disk_to_dev(pd->disk), "bio=%p sec0=%llx sec=%llx err=%d\n",
973 bio, pkt->sector, bio->bi_iter.bi_sector, bio->bi_status);
974
975 if (bio->bi_status)
976 atomic_inc(&pkt->io_errors);
977 bio_uninit(bio);
978 if (atomic_dec_and_test(&pkt->io_wait)) {
979 atomic_inc(&pkt->run_sm);
980 wake_up(&pd->wqueue);
981 }
982 pkt_bio_finished(pd);
983 }
984
pkt_end_io_packet_write(struct bio * bio)985 static void pkt_end_io_packet_write(struct bio *bio)
986 {
987 struct packet_data *pkt = bio->bi_private;
988 struct pktcdvd_device *pd = pkt->pd;
989 BUG_ON(!pd);
990
991 dev_dbg(disk_to_dev(pd->disk), "id=%d, err=%d\n", pkt->id, bio->bi_status);
992
993 pd->stats.pkt_ended++;
994
995 bio_uninit(bio);
996 pkt_bio_finished(pd);
997 atomic_dec(&pkt->io_wait);
998 atomic_inc(&pkt->run_sm);
999 wake_up(&pd->wqueue);
1000 }
1001
1002 /*
1003 * Schedule reads for the holes in a packet
1004 */
pkt_gather_data(struct pktcdvd_device * pd,struct packet_data * pkt)1005 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1006 {
1007 struct device *ddev = disk_to_dev(pd->disk);
1008 int frames_read = 0;
1009 struct bio *bio;
1010 int f;
1011 char written[PACKET_MAX_SIZE];
1012
1013 BUG_ON(bio_list_empty(&pkt->orig_bios));
1014
1015 atomic_set(&pkt->io_wait, 0);
1016 atomic_set(&pkt->io_errors, 0);
1017
1018 /*
1019 * Figure out which frames we need to read before we can write.
1020 */
1021 memset(written, 0, sizeof(written));
1022 spin_lock(&pkt->lock);
1023 bio_list_for_each(bio, &pkt->orig_bios) {
1024 int first_frame = (bio->bi_iter.bi_sector - pkt->sector) /
1025 (CD_FRAMESIZE >> 9);
1026 int num_frames = bio->bi_iter.bi_size / CD_FRAMESIZE;
1027 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1028 BUG_ON(first_frame < 0);
1029 BUG_ON(first_frame + num_frames > pkt->frames);
1030 for (f = first_frame; f < first_frame + num_frames; f++)
1031 written[f] = 1;
1032 }
1033 spin_unlock(&pkt->lock);
1034
1035 if (pkt->cache_valid) {
1036 dev_dbg(ddev, "zone %llx cached\n", pkt->sector);
1037 goto out_account;
1038 }
1039
1040 /*
1041 * Schedule reads for missing parts of the packet.
1042 */
1043 for (f = 0; f < pkt->frames; f++) {
1044 int p, offset;
1045
1046 if (written[f])
1047 continue;
1048
1049 bio = pkt->r_bios[f];
1050 bio_init(bio, pd->bdev, bio->bi_inline_vecs, 1, REQ_OP_READ);
1051 bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1052 bio->bi_end_io = pkt_end_io_read;
1053 bio->bi_private = pkt;
1054
1055 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1056 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1057 dev_dbg(ddev, "Adding frame %d, page:%p offs:%d\n", f,
1058 pkt->pages[p], offset);
1059 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1060 BUG();
1061
1062 atomic_inc(&pkt->io_wait);
1063 pkt_queue_bio(pd, bio);
1064 frames_read++;
1065 }
1066
1067 out_account:
1068 dev_dbg(ddev, "need %d frames for zone %llx\n", frames_read, pkt->sector);
1069 pd->stats.pkt_started++;
1070 pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1071 }
1072
1073 /*
1074 * Find a packet matching zone, or the least recently used packet if
1075 * there is no match.
1076 */
pkt_get_packet_data(struct pktcdvd_device * pd,int zone)1077 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1078 {
1079 struct packet_data *pkt;
1080
1081 list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1082 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1083 list_del_init(&pkt->list);
1084 if (pkt->sector != zone)
1085 pkt->cache_valid = 0;
1086 return pkt;
1087 }
1088 }
1089 BUG();
1090 return NULL;
1091 }
1092
pkt_put_packet_data(struct pktcdvd_device * pd,struct packet_data * pkt)1093 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1094 {
1095 if (pkt->cache_valid) {
1096 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1097 } else {
1098 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1099 }
1100 }
1101
pkt_set_state(struct device * ddev,struct packet_data * pkt,enum packet_data_state state)1102 static inline void pkt_set_state(struct device *ddev, struct packet_data *pkt,
1103 enum packet_data_state state)
1104 {
1105 static const char *state_name[] = {
1106 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1107 };
1108 enum packet_data_state old_state = pkt->state;
1109
1110 dev_dbg(ddev, "pkt %2d : s=%6llx %s -> %s\n",
1111 pkt->id, pkt->sector, state_name[old_state], state_name[state]);
1112
1113 pkt->state = state;
1114 }
1115
1116 /*
1117 * Scan the work queue to see if we can start a new packet.
1118 * returns non-zero if any work was done.
1119 */
pkt_handle_queue(struct pktcdvd_device * pd)1120 static int pkt_handle_queue(struct pktcdvd_device *pd)
1121 {
1122 struct device *ddev = disk_to_dev(pd->disk);
1123 struct packet_data *pkt, *p;
1124 struct bio *bio = NULL;
1125 sector_t zone = 0; /* Suppress gcc warning */
1126 struct pkt_rb_node *node, *first_node;
1127 struct rb_node *n;
1128
1129 atomic_set(&pd->scan_queue, 0);
1130
1131 if (list_empty(&pd->cdrw.pkt_free_list)) {
1132 dev_dbg(ddev, "no pkt\n");
1133 return 0;
1134 }
1135
1136 /*
1137 * Try to find a zone we are not already working on.
1138 */
1139 spin_lock(&pd->lock);
1140 first_node = pkt_rbtree_find(pd, pd->current_sector);
1141 if (!first_node) {
1142 n = rb_first(&pd->bio_queue);
1143 if (n)
1144 first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1145 }
1146 node = first_node;
1147 while (node) {
1148 bio = node->bio;
1149 zone = get_zone(bio->bi_iter.bi_sector, pd);
1150 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1151 if (p->sector == zone) {
1152 bio = NULL;
1153 goto try_next_bio;
1154 }
1155 }
1156 break;
1157 try_next_bio:
1158 node = pkt_rbtree_next(node);
1159 if (!node) {
1160 n = rb_first(&pd->bio_queue);
1161 if (n)
1162 node = rb_entry(n, struct pkt_rb_node, rb_node);
1163 }
1164 if (node == first_node)
1165 node = NULL;
1166 }
1167 spin_unlock(&pd->lock);
1168 if (!bio) {
1169 dev_dbg(ddev, "no bio\n");
1170 return 0;
1171 }
1172
1173 pkt = pkt_get_packet_data(pd, zone);
1174
1175 pd->current_sector = zone + pd->settings.size;
1176 pkt->sector = zone;
1177 BUG_ON(pkt->frames != pd->settings.size >> 2);
1178 pkt->write_size = 0;
1179
1180 /*
1181 * Scan work queue for bios in the same zone and link them
1182 * to this packet.
1183 */
1184 spin_lock(&pd->lock);
1185 dev_dbg(ddev, "looking for zone %llx\n", zone);
1186 while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1187 sector_t tmp = get_zone(node->bio->bi_iter.bi_sector, pd);
1188
1189 bio = node->bio;
1190 dev_dbg(ddev, "found zone=%llx\n", tmp);
1191 if (tmp != zone)
1192 break;
1193 pkt_rbtree_erase(pd, node);
1194 spin_lock(&pkt->lock);
1195 bio_list_add(&pkt->orig_bios, bio);
1196 pkt->write_size += bio->bi_iter.bi_size / CD_FRAMESIZE;
1197 spin_unlock(&pkt->lock);
1198 }
1199 /* check write congestion marks, and if bio_queue_size is
1200 * below, wake up any waiters
1201 */
1202 if (pd->congested &&
1203 pd->bio_queue_size <= pd->write_congestion_off) {
1204 pd->congested = false;
1205 wake_up_var(&pd->congested);
1206 }
1207 spin_unlock(&pd->lock);
1208
1209 pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1210 pkt_set_state(ddev, pkt, PACKET_WAITING_STATE);
1211 atomic_set(&pkt->run_sm, 1);
1212
1213 spin_lock(&pd->cdrw.active_list_lock);
1214 list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1215 spin_unlock(&pd->cdrw.active_list_lock);
1216
1217 return 1;
1218 }
1219
1220 /**
1221 * bio_list_copy_data - copy contents of data buffers from one chain of bios to
1222 * another
1223 * @src: source bio list
1224 * @dst: destination bio list
1225 *
1226 * Stops when it reaches the end of either the @src list or @dst list - that is,
1227 * copies min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of
1228 * bios).
1229 */
bio_list_copy_data(struct bio * dst,struct bio * src)1230 static void bio_list_copy_data(struct bio *dst, struct bio *src)
1231 {
1232 struct bvec_iter src_iter = src->bi_iter;
1233 struct bvec_iter dst_iter = dst->bi_iter;
1234
1235 while (1) {
1236 if (!src_iter.bi_size) {
1237 src = src->bi_next;
1238 if (!src)
1239 break;
1240
1241 src_iter = src->bi_iter;
1242 }
1243
1244 if (!dst_iter.bi_size) {
1245 dst = dst->bi_next;
1246 if (!dst)
1247 break;
1248
1249 dst_iter = dst->bi_iter;
1250 }
1251
1252 bio_copy_data_iter(dst, &dst_iter, src, &src_iter);
1253 }
1254 }
1255
1256 /*
1257 * Assemble a bio to write one packet and queue the bio for processing
1258 * by the underlying block device.
1259 */
pkt_start_write(struct pktcdvd_device * pd,struct packet_data * pkt)1260 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1261 {
1262 struct device *ddev = disk_to_dev(pd->disk);
1263 int f;
1264
1265 bio_init(pkt->w_bio, pd->bdev, pkt->w_bio->bi_inline_vecs, pkt->frames,
1266 REQ_OP_WRITE);
1267 pkt->w_bio->bi_iter.bi_sector = pkt->sector;
1268 pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1269 pkt->w_bio->bi_private = pkt;
1270
1271 /* XXX: locking? */
1272 for (f = 0; f < pkt->frames; f++) {
1273 struct page *page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1274 unsigned offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1275
1276 if (!bio_add_page(pkt->w_bio, page, CD_FRAMESIZE, offset))
1277 BUG();
1278 }
1279 dev_dbg(ddev, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
1280
1281 /*
1282 * Fill-in bvec with data from orig_bios.
1283 */
1284 spin_lock(&pkt->lock);
1285 bio_list_copy_data(pkt->w_bio, pkt->orig_bios.head);
1286
1287 pkt_set_state(ddev, pkt, PACKET_WRITE_WAIT_STATE);
1288 spin_unlock(&pkt->lock);
1289
1290 dev_dbg(ddev, "Writing %d frames for zone %llx\n", pkt->write_size, pkt->sector);
1291
1292 if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames))
1293 pkt->cache_valid = 1;
1294 else
1295 pkt->cache_valid = 0;
1296
1297 /* Start the write request */
1298 atomic_set(&pkt->io_wait, 1);
1299 pkt_queue_bio(pd, pkt->w_bio);
1300 }
1301
pkt_finish_packet(struct packet_data * pkt,blk_status_t status)1302 static void pkt_finish_packet(struct packet_data *pkt, blk_status_t status)
1303 {
1304 struct bio *bio;
1305
1306 if (status)
1307 pkt->cache_valid = 0;
1308
1309 /* Finish all bios corresponding to this packet */
1310 while ((bio = bio_list_pop(&pkt->orig_bios))) {
1311 bio->bi_status = status;
1312 bio_endio(bio);
1313 }
1314 }
1315
pkt_run_state_machine(struct pktcdvd_device * pd,struct packet_data * pkt)1316 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1317 {
1318 struct device *ddev = disk_to_dev(pd->disk);
1319
1320 dev_dbg(ddev, "pkt %d\n", pkt->id);
1321
1322 for (;;) {
1323 switch (pkt->state) {
1324 case PACKET_WAITING_STATE:
1325 if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1326 return;
1327
1328 pkt->sleep_time = 0;
1329 pkt_gather_data(pd, pkt);
1330 pkt_set_state(ddev, pkt, PACKET_READ_WAIT_STATE);
1331 break;
1332
1333 case PACKET_READ_WAIT_STATE:
1334 if (atomic_read(&pkt->io_wait) > 0)
1335 return;
1336
1337 if (atomic_read(&pkt->io_errors) > 0) {
1338 pkt_set_state(ddev, pkt, PACKET_RECOVERY_STATE);
1339 } else {
1340 pkt_start_write(pd, pkt);
1341 }
1342 break;
1343
1344 case PACKET_WRITE_WAIT_STATE:
1345 if (atomic_read(&pkt->io_wait) > 0)
1346 return;
1347
1348 if (!pkt->w_bio->bi_status) {
1349 pkt_set_state(ddev, pkt, PACKET_FINISHED_STATE);
1350 } else {
1351 pkt_set_state(ddev, pkt, PACKET_RECOVERY_STATE);
1352 }
1353 break;
1354
1355 case PACKET_RECOVERY_STATE:
1356 dev_dbg(ddev, "No recovery possible\n");
1357 pkt_set_state(ddev, pkt, PACKET_FINISHED_STATE);
1358 break;
1359
1360 case PACKET_FINISHED_STATE:
1361 pkt_finish_packet(pkt, pkt->w_bio->bi_status);
1362 return;
1363
1364 default:
1365 BUG();
1366 break;
1367 }
1368 }
1369 }
1370
pkt_handle_packets(struct pktcdvd_device * pd)1371 static void pkt_handle_packets(struct pktcdvd_device *pd)
1372 {
1373 struct device *ddev = disk_to_dev(pd->disk);
1374 struct packet_data *pkt, *next;
1375
1376 /*
1377 * Run state machine for active packets
1378 */
1379 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1380 if (atomic_read(&pkt->run_sm) > 0) {
1381 atomic_set(&pkt->run_sm, 0);
1382 pkt_run_state_machine(pd, pkt);
1383 }
1384 }
1385
1386 /*
1387 * Move no longer active packets to the free list
1388 */
1389 spin_lock(&pd->cdrw.active_list_lock);
1390 list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1391 if (pkt->state == PACKET_FINISHED_STATE) {
1392 list_del(&pkt->list);
1393 pkt_put_packet_data(pd, pkt);
1394 pkt_set_state(ddev, pkt, PACKET_IDLE_STATE);
1395 atomic_set(&pd->scan_queue, 1);
1396 }
1397 }
1398 spin_unlock(&pd->cdrw.active_list_lock);
1399 }
1400
1401 /*
1402 * kcdrwd is woken up when writes have been queued for one of our
1403 * registered devices
1404 */
kcdrwd(void * foobar)1405 static int kcdrwd(void *foobar)
1406 {
1407 struct pktcdvd_device *pd = foobar;
1408 struct device *ddev = disk_to_dev(pd->disk);
1409 struct packet_data *pkt;
1410 int states[PACKET_NUM_STATES];
1411 long min_sleep_time, residue;
1412
1413 set_user_nice(current, MIN_NICE);
1414 set_freezable();
1415
1416 for (;;) {
1417 DECLARE_WAITQUEUE(wait, current);
1418
1419 /*
1420 * Wait until there is something to do
1421 */
1422 add_wait_queue(&pd->wqueue, &wait);
1423 for (;;) {
1424 set_current_state(TASK_INTERRUPTIBLE);
1425
1426 /* Check if we need to run pkt_handle_queue */
1427 if (atomic_read(&pd->scan_queue) > 0)
1428 goto work_to_do;
1429
1430 /* Check if we need to run the state machine for some packet */
1431 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1432 if (atomic_read(&pkt->run_sm) > 0)
1433 goto work_to_do;
1434 }
1435
1436 /* Check if we need to process the iosched queues */
1437 if (atomic_read(&pd->iosched.attention) != 0)
1438 goto work_to_do;
1439
1440 /* Otherwise, go to sleep */
1441 pkt_count_states(pd, states);
1442 dev_dbg(ddev, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1443 states[0], states[1], states[2], states[3], states[4], states[5]);
1444
1445 min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1446 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1447 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1448 min_sleep_time = pkt->sleep_time;
1449 }
1450
1451 dev_dbg(ddev, "sleeping\n");
1452 residue = schedule_timeout(min_sleep_time);
1453 dev_dbg(ddev, "wake up\n");
1454
1455 /* make swsusp happy with our thread */
1456 try_to_freeze();
1457
1458 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1459 if (!pkt->sleep_time)
1460 continue;
1461 pkt->sleep_time -= min_sleep_time - residue;
1462 if (pkt->sleep_time <= 0) {
1463 pkt->sleep_time = 0;
1464 atomic_inc(&pkt->run_sm);
1465 }
1466 }
1467
1468 if (kthread_should_stop())
1469 break;
1470 }
1471 work_to_do:
1472 set_current_state(TASK_RUNNING);
1473 remove_wait_queue(&pd->wqueue, &wait);
1474
1475 if (kthread_should_stop())
1476 break;
1477
1478 /*
1479 * if pkt_handle_queue returns true, we can queue
1480 * another request.
1481 */
1482 while (pkt_handle_queue(pd))
1483 ;
1484
1485 /*
1486 * Handle packet state machine
1487 */
1488 pkt_handle_packets(pd);
1489
1490 /*
1491 * Handle iosched queues
1492 */
1493 pkt_iosched_process_queue(pd);
1494 }
1495
1496 return 0;
1497 }
1498
pkt_print_settings(struct pktcdvd_device * pd)1499 static void pkt_print_settings(struct pktcdvd_device *pd)
1500 {
1501 dev_info(disk_to_dev(pd->disk), "%s packets, %u blocks, Mode-%c disc\n",
1502 pd->settings.fp ? "Fixed" : "Variable",
1503 pd->settings.size >> 2,
1504 pd->settings.block_mode == 8 ? '1' : '2');
1505 }
1506
pkt_mode_sense(struct pktcdvd_device * pd,struct packet_command * cgc,int page_code,int page_control)1507 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1508 {
1509 memset(cgc->cmd, 0, sizeof(cgc->cmd));
1510
1511 cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1512 cgc->cmd[2] = page_code | (page_control << 6);
1513 put_unaligned_be16(cgc->buflen, &cgc->cmd[7]);
1514 cgc->data_direction = CGC_DATA_READ;
1515 return pkt_generic_packet(pd, cgc);
1516 }
1517
pkt_mode_select(struct pktcdvd_device * pd,struct packet_command * cgc)1518 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1519 {
1520 memset(cgc->cmd, 0, sizeof(cgc->cmd));
1521 memset(cgc->buffer, 0, 2);
1522 cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1523 cgc->cmd[1] = 0x10; /* PF */
1524 put_unaligned_be16(cgc->buflen, &cgc->cmd[7]);
1525 cgc->data_direction = CGC_DATA_WRITE;
1526 return pkt_generic_packet(pd, cgc);
1527 }
1528
pkt_get_disc_info(struct pktcdvd_device * pd,disc_information * di)1529 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1530 {
1531 struct packet_command cgc;
1532 int ret;
1533
1534 /* set up command and get the disc info */
1535 init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1536 cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1537 cgc.cmd[8] = cgc.buflen = 2;
1538 cgc.quiet = 1;
1539
1540 ret = pkt_generic_packet(pd, &cgc);
1541 if (ret)
1542 return ret;
1543
1544 /* not all drives have the same disc_info length, so requeue
1545 * packet with the length the drive tells us it can supply
1546 */
1547 cgc.buflen = be16_to_cpu(di->disc_information_length) +
1548 sizeof(di->disc_information_length);
1549
1550 if (cgc.buflen > sizeof(disc_information))
1551 cgc.buflen = sizeof(disc_information);
1552
1553 cgc.cmd[8] = cgc.buflen;
1554 return pkt_generic_packet(pd, &cgc);
1555 }
1556
pkt_get_track_info(struct pktcdvd_device * pd,__u16 track,__u8 type,track_information * ti)1557 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1558 {
1559 struct packet_command cgc;
1560 int ret;
1561
1562 init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1563 cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1564 cgc.cmd[1] = type & 3;
1565 put_unaligned_be16(track, &cgc.cmd[4]);
1566 cgc.cmd[8] = 8;
1567 cgc.quiet = 1;
1568
1569 ret = pkt_generic_packet(pd, &cgc);
1570 if (ret)
1571 return ret;
1572
1573 cgc.buflen = be16_to_cpu(ti->track_information_length) +
1574 sizeof(ti->track_information_length);
1575
1576 if (cgc.buflen > sizeof(track_information))
1577 cgc.buflen = sizeof(track_information);
1578
1579 cgc.cmd[8] = cgc.buflen;
1580 return pkt_generic_packet(pd, &cgc);
1581 }
1582
pkt_get_last_written(struct pktcdvd_device * pd,long * last_written)1583 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1584 long *last_written)
1585 {
1586 disc_information di;
1587 track_information ti;
1588 __u32 last_track;
1589 int ret;
1590
1591 ret = pkt_get_disc_info(pd, &di);
1592 if (ret)
1593 return ret;
1594
1595 last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1596 ret = pkt_get_track_info(pd, last_track, 1, &ti);
1597 if (ret)
1598 return ret;
1599
1600 /* if this track is blank, try the previous. */
1601 if (ti.blank) {
1602 last_track--;
1603 ret = pkt_get_track_info(pd, last_track, 1, &ti);
1604 if (ret)
1605 return ret;
1606 }
1607
1608 /* if last recorded field is valid, return it. */
1609 if (ti.lra_v) {
1610 *last_written = be32_to_cpu(ti.last_rec_address);
1611 } else {
1612 /* make it up instead */
1613 *last_written = be32_to_cpu(ti.track_start) +
1614 be32_to_cpu(ti.track_size);
1615 if (ti.free_blocks)
1616 *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1617 }
1618 return 0;
1619 }
1620
1621 /*
1622 * write mode select package based on pd->settings
1623 */
pkt_set_write_settings(struct pktcdvd_device * pd)1624 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1625 {
1626 struct device *ddev = disk_to_dev(pd->disk);
1627 struct packet_command cgc;
1628 struct scsi_sense_hdr sshdr;
1629 write_param_page *wp;
1630 char buffer[128];
1631 int ret, size;
1632
1633 /* doesn't apply to DVD+RW or DVD-RAM */
1634 if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1635 return 0;
1636
1637 memset(buffer, 0, sizeof(buffer));
1638 init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1639 cgc.sshdr = &sshdr;
1640 ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0);
1641 if (ret) {
1642 pkt_dump_sense(pd, &cgc);
1643 return ret;
1644 }
1645
1646 size = 2 + get_unaligned_be16(&buffer[0]);
1647 pd->mode_offset = get_unaligned_be16(&buffer[6]);
1648 if (size > sizeof(buffer))
1649 size = sizeof(buffer);
1650
1651 /*
1652 * now get it all
1653 */
1654 init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1655 cgc.sshdr = &sshdr;
1656 ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0);
1657 if (ret) {
1658 pkt_dump_sense(pd, &cgc);
1659 return ret;
1660 }
1661
1662 /*
1663 * write page is offset header + block descriptor length
1664 */
1665 wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1666
1667 wp->fp = pd->settings.fp;
1668 wp->track_mode = pd->settings.track_mode;
1669 wp->write_type = pd->settings.write_type;
1670 wp->data_block_type = pd->settings.block_mode;
1671
1672 wp->multi_session = 0;
1673
1674 #ifdef PACKET_USE_LS
1675 wp->link_size = 7;
1676 wp->ls_v = 1;
1677 #endif
1678
1679 if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1680 wp->session_format = 0;
1681 wp->subhdr2 = 0x20;
1682 } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1683 wp->session_format = 0x20;
1684 wp->subhdr2 = 8;
1685 #if 0
1686 wp->mcn[0] = 0x80;
1687 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1688 #endif
1689 } else {
1690 /*
1691 * paranoia
1692 */
1693 dev_err(ddev, "write mode wrong %d\n", wp->data_block_type);
1694 return 1;
1695 }
1696 wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1697
1698 cgc.buflen = cgc.cmd[8] = size;
1699 ret = pkt_mode_select(pd, &cgc);
1700 if (ret) {
1701 pkt_dump_sense(pd, &cgc);
1702 return ret;
1703 }
1704
1705 pkt_print_settings(pd);
1706 return 0;
1707 }
1708
1709 /*
1710 * 1 -- we can write to this track, 0 -- we can't
1711 */
pkt_writable_track(struct pktcdvd_device * pd,track_information * ti)1712 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1713 {
1714 struct device *ddev = disk_to_dev(pd->disk);
1715
1716 switch (pd->mmc3_profile) {
1717 case 0x1a: /* DVD+RW */
1718 case 0x12: /* DVD-RAM */
1719 /* The track is always writable on DVD+RW/DVD-RAM */
1720 return 1;
1721 default:
1722 break;
1723 }
1724
1725 if (!ti->packet || !ti->fp)
1726 return 0;
1727
1728 /*
1729 * "good" settings as per Mt Fuji.
1730 */
1731 if (ti->rt == 0 && ti->blank == 0)
1732 return 1;
1733
1734 if (ti->rt == 0 && ti->blank == 1)
1735 return 1;
1736
1737 if (ti->rt == 1 && ti->blank == 0)
1738 return 1;
1739
1740 dev_err(ddev, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1741 return 0;
1742 }
1743
1744 /*
1745 * 1 -- we can write to this disc, 0 -- we can't
1746 */
pkt_writable_disc(struct pktcdvd_device * pd,disc_information * di)1747 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1748 {
1749 struct device *ddev = disk_to_dev(pd->disk);
1750
1751 switch (pd->mmc3_profile) {
1752 case 0x0a: /* CD-RW */
1753 case 0xffff: /* MMC3 not supported */
1754 break;
1755 case 0x1a: /* DVD+RW */
1756 case 0x13: /* DVD-RW */
1757 case 0x12: /* DVD-RAM */
1758 return 1;
1759 default:
1760 dev_dbg(ddev, "Wrong disc profile (%x)\n", pd->mmc3_profile);
1761 return 0;
1762 }
1763
1764 /*
1765 * for disc type 0xff we should probably reserve a new track.
1766 * but i'm not sure, should we leave this to user apps? probably.
1767 */
1768 if (di->disc_type == 0xff) {
1769 dev_notice(ddev, "unknown disc - no track?\n");
1770 return 0;
1771 }
1772
1773 if (di->disc_type != 0x20 && di->disc_type != 0) {
1774 dev_err(ddev, "wrong disc type (%x)\n", di->disc_type);
1775 return 0;
1776 }
1777
1778 if (di->erasable == 0) {
1779 dev_err(ddev, "disc not erasable\n");
1780 return 0;
1781 }
1782
1783 if (di->border_status == PACKET_SESSION_RESERVED) {
1784 dev_err(ddev, "can't write to last track (reserved)\n");
1785 return 0;
1786 }
1787
1788 return 1;
1789 }
1790
pkt_probe_settings(struct pktcdvd_device * pd)1791 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1792 {
1793 struct device *ddev = disk_to_dev(pd->disk);
1794 struct packet_command cgc;
1795 unsigned char buf[12];
1796 disc_information di;
1797 track_information ti;
1798 int ret, track;
1799
1800 init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1801 cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1802 cgc.cmd[8] = 8;
1803 ret = pkt_generic_packet(pd, &cgc);
1804 pd->mmc3_profile = ret ? 0xffff : get_unaligned_be16(&buf[6]);
1805
1806 memset(&di, 0, sizeof(disc_information));
1807 memset(&ti, 0, sizeof(track_information));
1808
1809 ret = pkt_get_disc_info(pd, &di);
1810 if (ret) {
1811 dev_err(ddev, "failed get_disc\n");
1812 return ret;
1813 }
1814
1815 if (!pkt_writable_disc(pd, &di))
1816 return -EROFS;
1817
1818 pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1819
1820 track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1821 ret = pkt_get_track_info(pd, track, 1, &ti);
1822 if (ret) {
1823 dev_err(ddev, "failed get_track\n");
1824 return ret;
1825 }
1826
1827 if (!pkt_writable_track(pd, &ti)) {
1828 dev_err(ddev, "can't write to this track\n");
1829 return -EROFS;
1830 }
1831
1832 /*
1833 * we keep packet size in 512 byte units, makes it easier to
1834 * deal with request calculations.
1835 */
1836 pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1837 if (pd->settings.size == 0) {
1838 dev_notice(ddev, "detected zero packet size!\n");
1839 return -ENXIO;
1840 }
1841 if (pd->settings.size > PACKET_MAX_SECTORS) {
1842 dev_err(ddev, "packet size is too big\n");
1843 return -EROFS;
1844 }
1845 pd->settings.fp = ti.fp;
1846 pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1847
1848 if (ti.nwa_v) {
1849 pd->nwa = be32_to_cpu(ti.next_writable);
1850 set_bit(PACKET_NWA_VALID, &pd->flags);
1851 }
1852
1853 /*
1854 * in theory we could use lra on -RW media as well and just zero
1855 * blocks that haven't been written yet, but in practice that
1856 * is just a no-go. we'll use that for -R, naturally.
1857 */
1858 if (ti.lra_v) {
1859 pd->lra = be32_to_cpu(ti.last_rec_address);
1860 set_bit(PACKET_LRA_VALID, &pd->flags);
1861 } else {
1862 pd->lra = 0xffffffff;
1863 set_bit(PACKET_LRA_VALID, &pd->flags);
1864 }
1865
1866 /*
1867 * fine for now
1868 */
1869 pd->settings.link_loss = 7;
1870 pd->settings.write_type = 0; /* packet */
1871 pd->settings.track_mode = ti.track_mode;
1872
1873 /*
1874 * mode1 or mode2 disc
1875 */
1876 switch (ti.data_mode) {
1877 case PACKET_MODE1:
1878 pd->settings.block_mode = PACKET_BLOCK_MODE1;
1879 break;
1880 case PACKET_MODE2:
1881 pd->settings.block_mode = PACKET_BLOCK_MODE2;
1882 break;
1883 default:
1884 dev_err(ddev, "unknown data mode\n");
1885 return -EROFS;
1886 }
1887 return 0;
1888 }
1889
1890 /*
1891 * enable/disable write caching on drive
1892 */
pkt_write_caching(struct pktcdvd_device * pd)1893 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd)
1894 {
1895 struct device *ddev = disk_to_dev(pd->disk);
1896 struct packet_command cgc;
1897 struct scsi_sense_hdr sshdr;
1898 unsigned char buf[64];
1899 bool set = IS_ENABLED(CONFIG_CDROM_PKTCDVD_WCACHE);
1900 int ret;
1901
1902 init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1903 cgc.sshdr = &sshdr;
1904 cgc.buflen = pd->mode_offset + 12;
1905
1906 /*
1907 * caching mode page might not be there, so quiet this command
1908 */
1909 cgc.quiet = 1;
1910
1911 ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0);
1912 if (ret)
1913 return ret;
1914
1915 /*
1916 * use drive write caching -- we need deferred error handling to be
1917 * able to successfully recover with this option (drive will return good
1918 * status as soon as the cdb is validated).
1919 */
1920 buf[pd->mode_offset + 10] |= (set << 2);
1921
1922 cgc.buflen = cgc.cmd[8] = 2 + get_unaligned_be16(&buf[0]);
1923 ret = pkt_mode_select(pd, &cgc);
1924 if (ret) {
1925 dev_err(ddev, "write caching control failed\n");
1926 pkt_dump_sense(pd, &cgc);
1927 } else if (!ret && set)
1928 dev_notice(ddev, "enabled write caching\n");
1929 return ret;
1930 }
1931
pkt_lock_door(struct pktcdvd_device * pd,int lockflag)1932 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1933 {
1934 struct packet_command cgc;
1935
1936 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1937 cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1938 cgc.cmd[4] = lockflag ? 1 : 0;
1939 return pkt_generic_packet(pd, &cgc);
1940 }
1941
1942 /*
1943 * Returns drive maximum write speed
1944 */
pkt_get_max_speed(struct pktcdvd_device * pd,unsigned * write_speed)1945 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1946 unsigned *write_speed)
1947 {
1948 struct packet_command cgc;
1949 struct scsi_sense_hdr sshdr;
1950 unsigned char buf[256+18];
1951 unsigned char *cap_buf;
1952 int ret, offset;
1953
1954 cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1955 init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1956 cgc.sshdr = &sshdr;
1957
1958 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1959 if (ret) {
1960 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1961 sizeof(struct mode_page_header);
1962 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1963 if (ret) {
1964 pkt_dump_sense(pd, &cgc);
1965 return ret;
1966 }
1967 }
1968
1969 offset = 20; /* Obsoleted field, used by older drives */
1970 if (cap_buf[1] >= 28)
1971 offset = 28; /* Current write speed selected */
1972 if (cap_buf[1] >= 30) {
1973 /* If the drive reports at least one "Logical Unit Write
1974 * Speed Performance Descriptor Block", use the information
1975 * in the first block. (contains the highest speed)
1976 */
1977 int num_spdb = get_unaligned_be16(&cap_buf[30]);
1978 if (num_spdb > 0)
1979 offset = 34;
1980 }
1981
1982 *write_speed = get_unaligned_be16(&cap_buf[offset]);
1983 return 0;
1984 }
1985
1986 /* These tables from cdrecord - I don't have orange book */
1987 /* standard speed CD-RW (1-4x) */
1988 static char clv_to_speed[16] = {
1989 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
1990 0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1991 };
1992 /* high speed CD-RW (-10x) */
1993 static char hs_clv_to_speed[16] = {
1994 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
1995 0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1996 };
1997 /* ultra high speed CD-RW */
1998 static char us_clv_to_speed[16] = {
1999 /* 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 */
2000 0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2001 };
2002
2003 /*
2004 * reads the maximum media speed from ATIP
2005 */
pkt_media_speed(struct pktcdvd_device * pd,unsigned * speed)2006 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2007 unsigned *speed)
2008 {
2009 struct device *ddev = disk_to_dev(pd->disk);
2010 struct packet_command cgc;
2011 struct scsi_sense_hdr sshdr;
2012 unsigned char buf[64];
2013 unsigned int size, st, sp;
2014 int ret;
2015
2016 init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2017 cgc.sshdr = &sshdr;
2018 cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2019 cgc.cmd[1] = 2;
2020 cgc.cmd[2] = 4; /* READ ATIP */
2021 cgc.cmd[8] = 2;
2022 ret = pkt_generic_packet(pd, &cgc);
2023 if (ret) {
2024 pkt_dump_sense(pd, &cgc);
2025 return ret;
2026 }
2027 size = 2 + get_unaligned_be16(&buf[0]);
2028 if (size > sizeof(buf))
2029 size = sizeof(buf);
2030
2031 init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2032 cgc.sshdr = &sshdr;
2033 cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2034 cgc.cmd[1] = 2;
2035 cgc.cmd[2] = 4;
2036 cgc.cmd[8] = size;
2037 ret = pkt_generic_packet(pd, &cgc);
2038 if (ret) {
2039 pkt_dump_sense(pd, &cgc);
2040 return ret;
2041 }
2042
2043 if (!(buf[6] & 0x40)) {
2044 dev_notice(ddev, "disc type is not CD-RW\n");
2045 return 1;
2046 }
2047 if (!(buf[6] & 0x4)) {
2048 dev_notice(ddev, "A1 values on media are not valid, maybe not CDRW?\n");
2049 return 1;
2050 }
2051
2052 st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2053
2054 sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2055
2056 /* Info from cdrecord */
2057 switch (st) {
2058 case 0: /* standard speed */
2059 *speed = clv_to_speed[sp];
2060 break;
2061 case 1: /* high speed */
2062 *speed = hs_clv_to_speed[sp];
2063 break;
2064 case 2: /* ultra high speed */
2065 *speed = us_clv_to_speed[sp];
2066 break;
2067 default:
2068 dev_notice(ddev, "unknown disc sub-type %d\n", st);
2069 return 1;
2070 }
2071 if (*speed) {
2072 dev_info(ddev, "maximum media speed: %d\n", *speed);
2073 return 0;
2074 } else {
2075 dev_notice(ddev, "unknown speed %d for sub-type %d\n", sp, st);
2076 return 1;
2077 }
2078 }
2079
pkt_perform_opc(struct pktcdvd_device * pd)2080 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2081 {
2082 struct device *ddev = disk_to_dev(pd->disk);
2083 struct packet_command cgc;
2084 struct scsi_sense_hdr sshdr;
2085 int ret;
2086
2087 dev_dbg(ddev, "Performing OPC\n");
2088
2089 init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2090 cgc.sshdr = &sshdr;
2091 cgc.timeout = 60*HZ;
2092 cgc.cmd[0] = GPCMD_SEND_OPC;
2093 cgc.cmd[1] = 1;
2094 ret = pkt_generic_packet(pd, &cgc);
2095 if (ret)
2096 pkt_dump_sense(pd, &cgc);
2097 return ret;
2098 }
2099
pkt_open_write(struct pktcdvd_device * pd)2100 static int pkt_open_write(struct pktcdvd_device *pd)
2101 {
2102 struct device *ddev = disk_to_dev(pd->disk);
2103 int ret;
2104 unsigned int write_speed, media_write_speed, read_speed;
2105
2106 ret = pkt_probe_settings(pd);
2107 if (ret) {
2108 dev_dbg(ddev, "failed probe\n");
2109 return ret;
2110 }
2111
2112 ret = pkt_set_write_settings(pd);
2113 if (ret) {
2114 dev_notice(ddev, "failed saving write settings\n");
2115 return -EIO;
2116 }
2117
2118 pkt_write_caching(pd);
2119
2120 ret = pkt_get_max_speed(pd, &write_speed);
2121 if (ret)
2122 write_speed = 16 * 177;
2123 switch (pd->mmc3_profile) {
2124 case 0x13: /* DVD-RW */
2125 case 0x1a: /* DVD+RW */
2126 case 0x12: /* DVD-RAM */
2127 dev_notice(ddev, "write speed %ukB/s\n", write_speed);
2128 break;
2129 default:
2130 ret = pkt_media_speed(pd, &media_write_speed);
2131 if (ret)
2132 media_write_speed = 16;
2133 write_speed = min(write_speed, media_write_speed * 177);
2134 dev_notice(ddev, "write speed %ux\n", write_speed / 176);
2135 break;
2136 }
2137 read_speed = write_speed;
2138
2139 ret = pkt_set_speed(pd, write_speed, read_speed);
2140 if (ret) {
2141 dev_notice(ddev, "couldn't set write speed\n");
2142 return -EIO;
2143 }
2144 pd->write_speed = write_speed;
2145 pd->read_speed = read_speed;
2146
2147 ret = pkt_perform_opc(pd);
2148 if (ret)
2149 dev_notice(ddev, "Optimum Power Calibration failed\n");
2150
2151 return 0;
2152 }
2153
2154 /*
2155 * called at open time.
2156 */
pkt_open_dev(struct pktcdvd_device * pd,bool write)2157 static int pkt_open_dev(struct pktcdvd_device *pd, bool write)
2158 {
2159 struct device *ddev = disk_to_dev(pd->disk);
2160 int ret;
2161 long lba;
2162 struct request_queue *q;
2163 struct block_device *bdev;
2164
2165 /*
2166 * We need to re-open the cdrom device without O_NONBLOCK to be able
2167 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2168 * so open should not fail.
2169 */
2170 bdev = blkdev_get_by_dev(pd->bdev->bd_dev, BLK_OPEN_READ, pd, NULL);
2171 if (IS_ERR(bdev)) {
2172 ret = PTR_ERR(bdev);
2173 goto out;
2174 }
2175
2176 ret = pkt_get_last_written(pd, &lba);
2177 if (ret) {
2178 dev_err(ddev, "pkt_get_last_written failed\n");
2179 goto out_putdev;
2180 }
2181
2182 set_capacity(pd->disk, lba << 2);
2183 set_capacity_and_notify(pd->bdev->bd_disk, lba << 2);
2184
2185 q = bdev_get_queue(pd->bdev);
2186 if (write) {
2187 ret = pkt_open_write(pd);
2188 if (ret)
2189 goto out_putdev;
2190 /*
2191 * Some CDRW drives can not handle writes larger than one packet,
2192 * even if the size is a multiple of the packet size.
2193 */
2194 blk_queue_max_hw_sectors(q, pd->settings.size);
2195 set_bit(PACKET_WRITABLE, &pd->flags);
2196 } else {
2197 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2198 clear_bit(PACKET_WRITABLE, &pd->flags);
2199 }
2200
2201 ret = pkt_set_segment_merging(pd, q);
2202 if (ret)
2203 goto out_putdev;
2204
2205 if (write) {
2206 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2207 dev_err(ddev, "not enough memory for buffers\n");
2208 ret = -ENOMEM;
2209 goto out_putdev;
2210 }
2211 dev_info(ddev, "%lukB available on disc\n", lba << 1);
2212 }
2213
2214 return 0;
2215
2216 out_putdev:
2217 blkdev_put(bdev, pd);
2218 out:
2219 return ret;
2220 }
2221
2222 /*
2223 * called when the device is closed. makes sure that the device flushes
2224 * the internal cache before we close.
2225 */
pkt_release_dev(struct pktcdvd_device * pd,int flush)2226 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2227 {
2228 struct device *ddev = disk_to_dev(pd->disk);
2229
2230 if (flush && pkt_flush_cache(pd))
2231 dev_notice(ddev, "not flushing cache\n");
2232
2233 pkt_lock_door(pd, 0);
2234
2235 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2236 blkdev_put(pd->bdev, pd);
2237
2238 pkt_shrink_pktlist(pd);
2239 }
2240
pkt_find_dev_from_minor(unsigned int dev_minor)2241 static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2242 {
2243 if (dev_minor >= MAX_WRITERS)
2244 return NULL;
2245
2246 dev_minor = array_index_nospec(dev_minor, MAX_WRITERS);
2247 return pkt_devs[dev_minor];
2248 }
2249
pkt_open(struct gendisk * disk,blk_mode_t mode)2250 static int pkt_open(struct gendisk *disk, blk_mode_t mode)
2251 {
2252 struct pktcdvd_device *pd = NULL;
2253 int ret;
2254
2255 mutex_lock(&pktcdvd_mutex);
2256 mutex_lock(&ctl_mutex);
2257 pd = pkt_find_dev_from_minor(disk->first_minor);
2258 if (!pd) {
2259 ret = -ENODEV;
2260 goto out;
2261 }
2262 BUG_ON(pd->refcnt < 0);
2263
2264 pd->refcnt++;
2265 if (pd->refcnt > 1) {
2266 if ((mode & BLK_OPEN_WRITE) &&
2267 !test_bit(PACKET_WRITABLE, &pd->flags)) {
2268 ret = -EBUSY;
2269 goto out_dec;
2270 }
2271 } else {
2272 ret = pkt_open_dev(pd, mode & BLK_OPEN_WRITE);
2273 if (ret)
2274 goto out_dec;
2275 /*
2276 * needed here as well, since ext2 (among others) may change
2277 * the blocksize at mount time
2278 */
2279 set_blocksize(disk->part0, CD_FRAMESIZE);
2280 }
2281 mutex_unlock(&ctl_mutex);
2282 mutex_unlock(&pktcdvd_mutex);
2283 return 0;
2284
2285 out_dec:
2286 pd->refcnt--;
2287 out:
2288 mutex_unlock(&ctl_mutex);
2289 mutex_unlock(&pktcdvd_mutex);
2290 return ret;
2291 }
2292
pkt_release(struct gendisk * disk)2293 static void pkt_release(struct gendisk *disk)
2294 {
2295 struct pktcdvd_device *pd = disk->private_data;
2296
2297 mutex_lock(&pktcdvd_mutex);
2298 mutex_lock(&ctl_mutex);
2299 pd->refcnt--;
2300 BUG_ON(pd->refcnt < 0);
2301 if (pd->refcnt == 0) {
2302 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2303 pkt_release_dev(pd, flush);
2304 }
2305 mutex_unlock(&ctl_mutex);
2306 mutex_unlock(&pktcdvd_mutex);
2307 }
2308
2309
pkt_end_io_read_cloned(struct bio * bio)2310 static void pkt_end_io_read_cloned(struct bio *bio)
2311 {
2312 struct packet_stacked_data *psd = bio->bi_private;
2313 struct pktcdvd_device *pd = psd->pd;
2314
2315 psd->bio->bi_status = bio->bi_status;
2316 bio_put(bio);
2317 bio_endio(psd->bio);
2318 mempool_free(psd, &psd_pool);
2319 pkt_bio_finished(pd);
2320 }
2321
pkt_make_request_read(struct pktcdvd_device * pd,struct bio * bio)2322 static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio)
2323 {
2324 struct bio *cloned_bio =
2325 bio_alloc_clone(pd->bdev, bio, GFP_NOIO, &pkt_bio_set);
2326 struct packet_stacked_data *psd = mempool_alloc(&psd_pool, GFP_NOIO);
2327
2328 psd->pd = pd;
2329 psd->bio = bio;
2330 cloned_bio->bi_private = psd;
2331 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2332 pd->stats.secs_r += bio_sectors(bio);
2333 pkt_queue_bio(pd, cloned_bio);
2334 }
2335
pkt_make_request_write(struct request_queue * q,struct bio * bio)2336 static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
2337 {
2338 struct pktcdvd_device *pd = q->queuedata;
2339 sector_t zone;
2340 struct packet_data *pkt;
2341 int was_empty, blocked_bio;
2342 struct pkt_rb_node *node;
2343
2344 zone = get_zone(bio->bi_iter.bi_sector, pd);
2345
2346 /*
2347 * If we find a matching packet in state WAITING or READ_WAIT, we can
2348 * just append this bio to that packet.
2349 */
2350 spin_lock(&pd->cdrw.active_list_lock);
2351 blocked_bio = 0;
2352 list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2353 if (pkt->sector == zone) {
2354 spin_lock(&pkt->lock);
2355 if ((pkt->state == PACKET_WAITING_STATE) ||
2356 (pkt->state == PACKET_READ_WAIT_STATE)) {
2357 bio_list_add(&pkt->orig_bios, bio);
2358 pkt->write_size +=
2359 bio->bi_iter.bi_size / CD_FRAMESIZE;
2360 if ((pkt->write_size >= pkt->frames) &&
2361 (pkt->state == PACKET_WAITING_STATE)) {
2362 atomic_inc(&pkt->run_sm);
2363 wake_up(&pd->wqueue);
2364 }
2365 spin_unlock(&pkt->lock);
2366 spin_unlock(&pd->cdrw.active_list_lock);
2367 return;
2368 } else {
2369 blocked_bio = 1;
2370 }
2371 spin_unlock(&pkt->lock);
2372 }
2373 }
2374 spin_unlock(&pd->cdrw.active_list_lock);
2375
2376 /*
2377 * Test if there is enough room left in the bio work queue
2378 * (queue size >= congestion on mark).
2379 * If not, wait till the work queue size is below the congestion off mark.
2380 */
2381 spin_lock(&pd->lock);
2382 if (pd->write_congestion_on > 0
2383 && pd->bio_queue_size >= pd->write_congestion_on) {
2384 struct wait_bit_queue_entry wqe;
2385
2386 init_wait_var_entry(&wqe, &pd->congested, 0);
2387 for (;;) {
2388 prepare_to_wait_event(__var_waitqueue(&pd->congested),
2389 &wqe.wq_entry,
2390 TASK_UNINTERRUPTIBLE);
2391 if (pd->bio_queue_size <= pd->write_congestion_off)
2392 break;
2393 pd->congested = true;
2394 spin_unlock(&pd->lock);
2395 schedule();
2396 spin_lock(&pd->lock);
2397 }
2398 }
2399 spin_unlock(&pd->lock);
2400
2401 /*
2402 * No matching packet found. Store the bio in the work queue.
2403 */
2404 node = mempool_alloc(&pd->rb_pool, GFP_NOIO);
2405 node->bio = bio;
2406 spin_lock(&pd->lock);
2407 BUG_ON(pd->bio_queue_size < 0);
2408 was_empty = (pd->bio_queue_size == 0);
2409 pkt_rbtree_insert(pd, node);
2410 spin_unlock(&pd->lock);
2411
2412 /*
2413 * Wake up the worker thread.
2414 */
2415 atomic_set(&pd->scan_queue, 1);
2416 if (was_empty) {
2417 /* This wake_up is required for correct operation */
2418 wake_up(&pd->wqueue);
2419 } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2420 /*
2421 * This wake up is not required for correct operation,
2422 * but improves performance in some cases.
2423 */
2424 wake_up(&pd->wqueue);
2425 }
2426 }
2427
pkt_submit_bio(struct bio * bio)2428 static void pkt_submit_bio(struct bio *bio)
2429 {
2430 struct pktcdvd_device *pd = bio->bi_bdev->bd_disk->queue->queuedata;
2431 struct device *ddev = disk_to_dev(pd->disk);
2432 struct bio *split;
2433
2434 bio = bio_split_to_limits(bio);
2435 if (!bio)
2436 return;
2437
2438 dev_dbg(ddev, "start = %6llx stop = %6llx\n",
2439 bio->bi_iter.bi_sector, bio_end_sector(bio));
2440
2441 /*
2442 * Clone READ bios so we can have our own bi_end_io callback.
2443 */
2444 if (bio_data_dir(bio) == READ) {
2445 pkt_make_request_read(pd, bio);
2446 return;
2447 }
2448
2449 if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2450 dev_notice(ddev, "WRITE for ro device (%llu)\n", bio->bi_iter.bi_sector);
2451 goto end_io;
2452 }
2453
2454 if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) {
2455 dev_err(ddev, "wrong bio size\n");
2456 goto end_io;
2457 }
2458
2459 do {
2460 sector_t zone = get_zone(bio->bi_iter.bi_sector, pd);
2461 sector_t last_zone = get_zone(bio_end_sector(bio) - 1, pd);
2462
2463 if (last_zone != zone) {
2464 BUG_ON(last_zone != zone + pd->settings.size);
2465
2466 split = bio_split(bio, last_zone -
2467 bio->bi_iter.bi_sector,
2468 GFP_NOIO, &pkt_bio_set);
2469 bio_chain(split, bio);
2470 } else {
2471 split = bio;
2472 }
2473
2474 pkt_make_request_write(bio->bi_bdev->bd_disk->queue, split);
2475 } while (split != bio);
2476
2477 return;
2478 end_io:
2479 bio_io_error(bio);
2480 }
2481
pkt_init_queue(struct pktcdvd_device * pd)2482 static void pkt_init_queue(struct pktcdvd_device *pd)
2483 {
2484 struct request_queue *q = pd->disk->queue;
2485
2486 blk_queue_logical_block_size(q, CD_FRAMESIZE);
2487 blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2488 q->queuedata = pd;
2489 }
2490
pkt_new_dev(struct pktcdvd_device * pd,dev_t dev)2491 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2492 {
2493 struct device *ddev = disk_to_dev(pd->disk);
2494 int i;
2495 struct block_device *bdev;
2496 struct scsi_device *sdev;
2497
2498 if (pd->pkt_dev == dev) {
2499 dev_err(ddev, "recursive setup not allowed\n");
2500 return -EBUSY;
2501 }
2502 for (i = 0; i < MAX_WRITERS; i++) {
2503 struct pktcdvd_device *pd2 = pkt_devs[i];
2504 if (!pd2)
2505 continue;
2506 if (pd2->bdev->bd_dev == dev) {
2507 dev_err(ddev, "%pg already setup\n", pd2->bdev);
2508 return -EBUSY;
2509 }
2510 if (pd2->pkt_dev == dev) {
2511 dev_err(ddev, "can't chain pktcdvd devices\n");
2512 return -EBUSY;
2513 }
2514 }
2515
2516 bdev = blkdev_get_by_dev(dev, BLK_OPEN_READ | BLK_OPEN_NDELAY, NULL,
2517 NULL);
2518 if (IS_ERR(bdev))
2519 return PTR_ERR(bdev);
2520 sdev = scsi_device_from_queue(bdev->bd_disk->queue);
2521 if (!sdev) {
2522 blkdev_put(bdev, NULL);
2523 return -EINVAL;
2524 }
2525 put_device(&sdev->sdev_gendev);
2526
2527 /* This is safe, since we have a reference from open(). */
2528 __module_get(THIS_MODULE);
2529
2530 pd->bdev = bdev;
2531 set_blocksize(bdev, CD_FRAMESIZE);
2532
2533 pkt_init_queue(pd);
2534
2535 atomic_set(&pd->cdrw.pending_bios, 0);
2536 pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->disk->disk_name);
2537 if (IS_ERR(pd->cdrw.thread)) {
2538 dev_err(ddev, "can't start kernel thread\n");
2539 goto out_mem;
2540 }
2541
2542 proc_create_single_data(pd->disk->disk_name, 0, pkt_proc, pkt_seq_show, pd);
2543 dev_notice(ddev, "writer mapped to %pg\n", bdev);
2544 return 0;
2545
2546 out_mem:
2547 blkdev_put(bdev, NULL);
2548 /* This is safe: open() is still holding a reference. */
2549 module_put(THIS_MODULE);
2550 return -ENOMEM;
2551 }
2552
pkt_ioctl(struct block_device * bdev,blk_mode_t mode,unsigned int cmd,unsigned long arg)2553 static int pkt_ioctl(struct block_device *bdev, blk_mode_t mode,
2554 unsigned int cmd, unsigned long arg)
2555 {
2556 struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2557 struct device *ddev = disk_to_dev(pd->disk);
2558 int ret;
2559
2560 dev_dbg(ddev, "cmd %x, dev %d:%d\n", cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2561
2562 mutex_lock(&pktcdvd_mutex);
2563 switch (cmd) {
2564 case CDROMEJECT:
2565 /*
2566 * The door gets locked when the device is opened, so we
2567 * have to unlock it or else the eject command fails.
2568 */
2569 if (pd->refcnt == 1)
2570 pkt_lock_door(pd, 0);
2571 fallthrough;
2572 /*
2573 * forward selected CDROM ioctls to CD-ROM, for UDF
2574 */
2575 case CDROMMULTISESSION:
2576 case CDROMREADTOCENTRY:
2577 case CDROM_LAST_WRITTEN:
2578 case CDROM_SEND_PACKET:
2579 case SCSI_IOCTL_SEND_COMMAND:
2580 if (!bdev->bd_disk->fops->ioctl)
2581 ret = -ENOTTY;
2582 else
2583 ret = bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
2584 break;
2585 default:
2586 dev_dbg(ddev, "Unknown ioctl (%x)\n", cmd);
2587 ret = -ENOTTY;
2588 }
2589 mutex_unlock(&pktcdvd_mutex);
2590
2591 return ret;
2592 }
2593
pkt_check_events(struct gendisk * disk,unsigned int clearing)2594 static unsigned int pkt_check_events(struct gendisk *disk,
2595 unsigned int clearing)
2596 {
2597 struct pktcdvd_device *pd = disk->private_data;
2598 struct gendisk *attached_disk;
2599
2600 if (!pd)
2601 return 0;
2602 if (!pd->bdev)
2603 return 0;
2604 attached_disk = pd->bdev->bd_disk;
2605 if (!attached_disk || !attached_disk->fops->check_events)
2606 return 0;
2607 return attached_disk->fops->check_events(attached_disk, clearing);
2608 }
2609
pkt_devnode(struct gendisk * disk,umode_t * mode)2610 static char *pkt_devnode(struct gendisk *disk, umode_t *mode)
2611 {
2612 return kasprintf(GFP_KERNEL, "pktcdvd/%s", disk->disk_name);
2613 }
2614
2615 static const struct block_device_operations pktcdvd_ops = {
2616 .owner = THIS_MODULE,
2617 .submit_bio = pkt_submit_bio,
2618 .open = pkt_open,
2619 .release = pkt_release,
2620 .ioctl = pkt_ioctl,
2621 .compat_ioctl = blkdev_compat_ptr_ioctl,
2622 .check_events = pkt_check_events,
2623 .devnode = pkt_devnode,
2624 };
2625
2626 /*
2627 * Set up mapping from pktcdvd device to CD-ROM device.
2628 */
pkt_setup_dev(dev_t dev,dev_t * pkt_dev)2629 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2630 {
2631 int idx;
2632 int ret = -ENOMEM;
2633 struct pktcdvd_device *pd;
2634 struct gendisk *disk;
2635
2636 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2637
2638 for (idx = 0; idx < MAX_WRITERS; idx++)
2639 if (!pkt_devs[idx])
2640 break;
2641 if (idx == MAX_WRITERS) {
2642 pr_err("max %d writers supported\n", MAX_WRITERS);
2643 ret = -EBUSY;
2644 goto out_mutex;
2645 }
2646
2647 pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2648 if (!pd)
2649 goto out_mutex;
2650
2651 ret = mempool_init_kmalloc_pool(&pd->rb_pool, PKT_RB_POOL_SIZE,
2652 sizeof(struct pkt_rb_node));
2653 if (ret)
2654 goto out_mem;
2655
2656 INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2657 INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2658 spin_lock_init(&pd->cdrw.active_list_lock);
2659
2660 spin_lock_init(&pd->lock);
2661 spin_lock_init(&pd->iosched.lock);
2662 bio_list_init(&pd->iosched.read_queue);
2663 bio_list_init(&pd->iosched.write_queue);
2664 init_waitqueue_head(&pd->wqueue);
2665 pd->bio_queue = RB_ROOT;
2666
2667 pd->write_congestion_on = write_congestion_on;
2668 pd->write_congestion_off = write_congestion_off;
2669
2670 ret = -ENOMEM;
2671 disk = blk_alloc_disk(NUMA_NO_NODE);
2672 if (!disk)
2673 goto out_mem;
2674 pd->disk = disk;
2675 disk->major = pktdev_major;
2676 disk->first_minor = idx;
2677 disk->minors = 1;
2678 disk->fops = &pktcdvd_ops;
2679 disk->flags = GENHD_FL_REMOVABLE | GENHD_FL_NO_PART;
2680 snprintf(disk->disk_name, sizeof(disk->disk_name), DRIVER_NAME"%d", idx);
2681 disk->private_data = pd;
2682
2683 pd->pkt_dev = MKDEV(pktdev_major, idx);
2684 ret = pkt_new_dev(pd, dev);
2685 if (ret)
2686 goto out_mem2;
2687
2688 /* inherit events of the host device */
2689 disk->events = pd->bdev->bd_disk->events;
2690
2691 ret = add_disk(disk);
2692 if (ret)
2693 goto out_mem2;
2694
2695 pkt_sysfs_dev_new(pd);
2696 pkt_debugfs_dev_new(pd);
2697
2698 pkt_devs[idx] = pd;
2699 if (pkt_dev)
2700 *pkt_dev = pd->pkt_dev;
2701
2702 mutex_unlock(&ctl_mutex);
2703 return 0;
2704
2705 out_mem2:
2706 put_disk(disk);
2707 out_mem:
2708 mempool_exit(&pd->rb_pool);
2709 kfree(pd);
2710 out_mutex:
2711 mutex_unlock(&ctl_mutex);
2712 pr_err("setup of pktcdvd device failed\n");
2713 return ret;
2714 }
2715
2716 /*
2717 * Tear down mapping from pktcdvd device to CD-ROM device.
2718 */
pkt_remove_dev(dev_t pkt_dev)2719 static int pkt_remove_dev(dev_t pkt_dev)
2720 {
2721 struct pktcdvd_device *pd;
2722 struct device *ddev;
2723 int idx;
2724 int ret = 0;
2725
2726 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2727
2728 for (idx = 0; idx < MAX_WRITERS; idx++) {
2729 pd = pkt_devs[idx];
2730 if (pd && (pd->pkt_dev == pkt_dev))
2731 break;
2732 }
2733 if (idx == MAX_WRITERS) {
2734 pr_debug("dev not setup\n");
2735 ret = -ENXIO;
2736 goto out;
2737 }
2738
2739 if (pd->refcnt > 0) {
2740 ret = -EBUSY;
2741 goto out;
2742 }
2743
2744 ddev = disk_to_dev(pd->disk);
2745
2746 if (!IS_ERR(pd->cdrw.thread))
2747 kthread_stop(pd->cdrw.thread);
2748
2749 pkt_devs[idx] = NULL;
2750
2751 pkt_debugfs_dev_remove(pd);
2752 pkt_sysfs_dev_remove(pd);
2753
2754 blkdev_put(pd->bdev, NULL);
2755
2756 remove_proc_entry(pd->disk->disk_name, pkt_proc);
2757 dev_notice(ddev, "writer unmapped\n");
2758
2759 del_gendisk(pd->disk);
2760 put_disk(pd->disk);
2761
2762 mempool_exit(&pd->rb_pool);
2763 kfree(pd);
2764
2765 /* This is safe: open() is still holding a reference. */
2766 module_put(THIS_MODULE);
2767
2768 out:
2769 mutex_unlock(&ctl_mutex);
2770 return ret;
2771 }
2772
pkt_get_status(struct pkt_ctrl_command * ctrl_cmd)2773 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2774 {
2775 struct pktcdvd_device *pd;
2776
2777 mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2778
2779 pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2780 if (pd) {
2781 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2782 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2783 } else {
2784 ctrl_cmd->dev = 0;
2785 ctrl_cmd->pkt_dev = 0;
2786 }
2787 ctrl_cmd->num_devices = MAX_WRITERS;
2788
2789 mutex_unlock(&ctl_mutex);
2790 }
2791
pkt_ctl_ioctl(struct file * file,unsigned int cmd,unsigned long arg)2792 static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2793 {
2794 void __user *argp = (void __user *)arg;
2795 struct pkt_ctrl_command ctrl_cmd;
2796 int ret = 0;
2797 dev_t pkt_dev = 0;
2798
2799 if (cmd != PACKET_CTRL_CMD)
2800 return -ENOTTY;
2801
2802 if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2803 return -EFAULT;
2804
2805 switch (ctrl_cmd.command) {
2806 case PKT_CTRL_CMD_SETUP:
2807 if (!capable(CAP_SYS_ADMIN))
2808 return -EPERM;
2809 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2810 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2811 break;
2812 case PKT_CTRL_CMD_TEARDOWN:
2813 if (!capable(CAP_SYS_ADMIN))
2814 return -EPERM;
2815 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2816 break;
2817 case PKT_CTRL_CMD_STATUS:
2818 pkt_get_status(&ctrl_cmd);
2819 break;
2820 default:
2821 return -ENOTTY;
2822 }
2823
2824 if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2825 return -EFAULT;
2826 return ret;
2827 }
2828
2829 #ifdef CONFIG_COMPAT
pkt_ctl_compat_ioctl(struct file * file,unsigned int cmd,unsigned long arg)2830 static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2831 {
2832 return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2833 }
2834 #endif
2835
2836 static const struct file_operations pkt_ctl_fops = {
2837 .open = nonseekable_open,
2838 .unlocked_ioctl = pkt_ctl_ioctl,
2839 #ifdef CONFIG_COMPAT
2840 .compat_ioctl = pkt_ctl_compat_ioctl,
2841 #endif
2842 .owner = THIS_MODULE,
2843 .llseek = no_llseek,
2844 };
2845
2846 static struct miscdevice pkt_misc = {
2847 .minor = MISC_DYNAMIC_MINOR,
2848 .name = DRIVER_NAME,
2849 .nodename = "pktcdvd/control",
2850 .fops = &pkt_ctl_fops
2851 };
2852
pkt_init(void)2853 static int __init pkt_init(void)
2854 {
2855 int ret;
2856
2857 mutex_init(&ctl_mutex);
2858
2859 ret = mempool_init_kmalloc_pool(&psd_pool, PSD_POOL_SIZE,
2860 sizeof(struct packet_stacked_data));
2861 if (ret)
2862 return ret;
2863 ret = bioset_init(&pkt_bio_set, BIO_POOL_SIZE, 0, 0);
2864 if (ret) {
2865 mempool_exit(&psd_pool);
2866 return ret;
2867 }
2868
2869 ret = register_blkdev(pktdev_major, DRIVER_NAME);
2870 if (ret < 0) {
2871 pr_err("unable to register block device\n");
2872 goto out2;
2873 }
2874 if (!pktdev_major)
2875 pktdev_major = ret;
2876
2877 ret = pkt_sysfs_init();
2878 if (ret)
2879 goto out;
2880
2881 pkt_debugfs_init();
2882
2883 ret = misc_register(&pkt_misc);
2884 if (ret) {
2885 pr_err("unable to register misc device\n");
2886 goto out_misc;
2887 }
2888
2889 pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
2890
2891 return 0;
2892
2893 out_misc:
2894 pkt_debugfs_cleanup();
2895 pkt_sysfs_cleanup();
2896 out:
2897 unregister_blkdev(pktdev_major, DRIVER_NAME);
2898 out2:
2899 mempool_exit(&psd_pool);
2900 bioset_exit(&pkt_bio_set);
2901 return ret;
2902 }
2903
pkt_exit(void)2904 static void __exit pkt_exit(void)
2905 {
2906 remove_proc_entry("driver/"DRIVER_NAME, NULL);
2907 misc_deregister(&pkt_misc);
2908
2909 pkt_debugfs_cleanup();
2910 pkt_sysfs_cleanup();
2911
2912 unregister_blkdev(pktdev_major, DRIVER_NAME);
2913 mempool_exit(&psd_pool);
2914 bioset_exit(&pkt_bio_set);
2915 }
2916
2917 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2918 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2919 MODULE_LICENSE("GPL");
2920
2921 module_init(pkt_init);
2922 module_exit(pkt_exit);
2923