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v5.9
   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 ->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/pktcdvd.h>
  50#include <linux/module.h>
  51#include <linux/types.h>
  52#include <linux/kernel.h>
  53#include <linux/compat.h>
  54#include <linux/kthread.h>
  55#include <linux/errno.h>
  56#include <linux/spinlock.h>
  57#include <linux/file.h>
  58#include <linux/proc_fs.h>
  59#include <linux/seq_file.h>
  60#include <linux/miscdevice.h>
  61#include <linux/freezer.h>
  62#include <linux/mutex.h>
  63#include <linux/slab.h>
  64#include <linux/backing-dev.h>
  65#include <scsi/scsi_cmnd.h>
  66#include <scsi/scsi_ioctl.h>
  67#include <scsi/scsi.h>
  68#include <linux/debugfs.h>
  69#include <linux/device.h>
  70#include <linux/nospec.h>
  71#include <linux/uaccess.h>
  72
  73#define DRIVER_NAME	"pktcdvd"
  74
  75#define pkt_err(pd, fmt, ...)						\
  76	pr_err("%s: " fmt, pd->name, ##__VA_ARGS__)
  77#define pkt_notice(pd, fmt, ...)					\
  78	pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__)
  79#define pkt_info(pd, fmt, ...)						\
  80	pr_info("%s: " fmt, pd->name, ##__VA_ARGS__)
  81
  82#define pkt_dbg(level, pd, fmt, ...)					\
  83do {									\
  84	if (level == 2 && PACKET_DEBUG >= 2)				\
  85		pr_notice("%s: %s():" fmt,				\
  86			  pd->name, __func__, ##__VA_ARGS__);		\
  87	else if (level == 1 && PACKET_DEBUG >= 1)			\
  88		pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__);		\
  89} while (0)
  90
  91#define MAX_SPEED 0xffff
  92
  93static DEFINE_MUTEX(pktcdvd_mutex);
  94static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  95static struct proc_dir_entry *pkt_proc;
  96static int pktdev_major;
  97static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
  98static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
  99static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
 100static mempool_t psd_pool;
 101static struct bio_set pkt_bio_set;
 102
 103static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
 104static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
 105
 106/* forward declaration */
 107static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
 108static int pkt_remove_dev(dev_t pkt_dev);
 109static int pkt_seq_show(struct seq_file *m, void *p);
 110
 111static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
 112{
 113	return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1);
 114}
 115
 116/*
 117 * create and register a pktcdvd kernel object.
 118 */
 119static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
 120					const char* name,
 121					struct kobject* parent,
 122					struct kobj_type* ktype)
 123{
 124	struct pktcdvd_kobj *p;
 125	int error;
 126
 127	p = kzalloc(sizeof(*p), GFP_KERNEL);
 128	if (!p)
 129		return NULL;
 130	p->pd = pd;
 131	error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
 132	if (error) {
 133		kobject_put(&p->kobj);
 134		return NULL;
 135	}
 136	kobject_uevent(&p->kobj, KOBJ_ADD);
 137	return p;
 138}
 139/*
 140 * remove a pktcdvd kernel object.
 141 */
 142static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 143{
 144	if (p)
 145		kobject_put(&p->kobj);
 146}
 147/*
 148 * default release function for pktcdvd kernel objects.
 149 */
 150static void pkt_kobj_release(struct kobject *kobj)
 151{
 152	kfree(to_pktcdvdkobj(kobj));
 153}
 154
 155
 156/**********************************************************
 157 *
 158 * sysfs interface for pktcdvd
 159 * by (C) 2006  Thomas Maier <balagi@justmail.de>
 160 *
 161 **********************************************************/
 162
 163#define DEF_ATTR(_obj,_name,_mode) \
 164	static struct attribute _obj = { .name = _name, .mode = _mode }
 165
 166/**********************************************************
 167  /sys/class/pktcdvd/pktcdvd[0-7]/
 168                     stat/reset
 169                     stat/packets_started
 170                     stat/packets_finished
 171                     stat/kb_written
 172                     stat/kb_read
 173                     stat/kb_read_gather
 174                     write_queue/size
 175                     write_queue/congestion_off
 176                     write_queue/congestion_on
 177 **********************************************************/
 178
 179DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 180DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 181DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 182DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 183DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 184DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 185
 186static struct attribute *kobj_pkt_attrs_stat[] = {
 187	&kobj_pkt_attr_st1,
 188	&kobj_pkt_attr_st2,
 189	&kobj_pkt_attr_st3,
 190	&kobj_pkt_attr_st4,
 191	&kobj_pkt_attr_st5,
 192	&kobj_pkt_attr_st6,
 193	NULL
 194};
 195
 196DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 197DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 198DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 199
 200static struct attribute *kobj_pkt_attrs_wqueue[] = {
 201	&kobj_pkt_attr_wq1,
 202	&kobj_pkt_attr_wq2,
 203	&kobj_pkt_attr_wq3,
 204	NULL
 205};
 206
 207static ssize_t kobj_pkt_show(struct kobject *kobj,
 208			struct attribute *attr, char *data)
 209{
 210	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 211	int n = 0;
 212	int v;
 213	if (strcmp(attr->name, "packets_started") == 0) {
 214		n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 215
 216	} else if (strcmp(attr->name, "packets_finished") == 0) {
 217		n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 
 218
 219	} else if (strcmp(attr->name, "kb_written") == 0) {
 220		n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 
 
 221
 222	} else if (strcmp(attr->name, "kb_read") == 0) {
 223		n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 
 224
 225	} else if (strcmp(attr->name, "kb_read_gather") == 0) {
 226		n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 
 
 227
 228	} else if (strcmp(attr->name, "size") == 0) {
 229		spin_lock(&pd->lock);
 230		v = pd->bio_queue_size;
 231		spin_unlock(&pd->lock);
 232		n = sprintf(data, "%d\n", v);
 233
 234	} else if (strcmp(attr->name, "congestion_off") == 0) {
 235		spin_lock(&pd->lock);
 236		v = pd->write_congestion_off;
 237		spin_unlock(&pd->lock);
 238		n = sprintf(data, "%d\n", v);
 239
 240	} else if (strcmp(attr->name, "congestion_on") == 0) {
 241		spin_lock(&pd->lock);
 242		v = pd->write_congestion_on;
 243		spin_unlock(&pd->lock);
 244		n = sprintf(data, "%d\n", v);
 
 
 
 
 
 
 
 
 
 
 245	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 246	return n;
 247}
 
 248
 249static void init_write_congestion_marks(int* lo, int* hi)
 250{
 251	if (*hi > 0) {
 252		*hi = max(*hi, 500);
 253		*hi = min(*hi, 1000000);
 254		if (*lo <= 0)
 255			*lo = *hi - 100;
 256		else {
 257			*lo = min(*lo, *hi - 100);
 258			*lo = max(*lo, 100);
 259		}
 260	} else {
 261		*hi = -1;
 262		*lo = -1;
 263	}
 264}
 265
 266static ssize_t kobj_pkt_store(struct kobject *kobj,
 267			struct attribute *attr,
 268			const char *data, size_t len)
 269{
 270	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 271	int val;
 272
 273	if (strcmp(attr->name, "reset") == 0 && len > 0) {
 274		pd->stats.pkt_started = 0;
 275		pd->stats.pkt_ended = 0;
 276		pd->stats.secs_w = 0;
 277		pd->stats.secs_rg = 0;
 278		pd->stats.secs_r = 0;
 279
 280	} else if (strcmp(attr->name, "congestion_off") == 0
 281		   && sscanf(data, "%d", &val) == 1) {
 
 
 
 
 
 
 282		spin_lock(&pd->lock);
 283		pd->write_congestion_off = val;
 284		init_write_congestion_marks(&pd->write_congestion_off,
 285					&pd->write_congestion_on);
 286		spin_unlock(&pd->lock);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 287
 288	} else if (strcmp(attr->name, "congestion_on") == 0
 289		   && sscanf(data, "%d", &val) == 1) {
 
 
 
 
 
 
 290		spin_lock(&pd->lock);
 291		pd->write_congestion_on = val;
 292		init_write_congestion_marks(&pd->write_congestion_off,
 293					&pd->write_congestion_on);
 294		spin_unlock(&pd->lock);
 295	}
 296	return len;
 297}
 
 298
 299static const struct sysfs_ops kobj_pkt_ops = {
 300	.show = kobj_pkt_show,
 301	.store = kobj_pkt_store
 
 
 302};
 303static struct kobj_type kobj_pkt_type_stat = {
 304	.release = pkt_kobj_release,
 305	.sysfs_ops = &kobj_pkt_ops,
 306	.default_attrs = kobj_pkt_attrs_stat
 307};
 308static struct kobj_type kobj_pkt_type_wqueue = {
 309	.release = pkt_kobj_release,
 310	.sysfs_ops = &kobj_pkt_ops,
 311	.default_attrs = kobj_pkt_attrs_wqueue
 
 312};
 313
 314static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 315{
 316	if (class_pktcdvd) {
 317		pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
 318					"%s", pd->name);
 
 319		if (IS_ERR(pd->dev))
 320			pd->dev = NULL;
 321	}
 322	if (pd->dev) {
 323		pd->kobj_stat = pkt_kobj_create(pd, "stat",
 324					&pd->dev->kobj,
 325					&kobj_pkt_type_stat);
 326		pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 327					&pd->dev->kobj,
 328					&kobj_pkt_type_wqueue);
 329	}
 330}
 331
 332static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 333{
 334	pkt_kobj_remove(pd->kobj_stat);
 335	pkt_kobj_remove(pd->kobj_wqueue);
 336	if (class_pktcdvd)
 337		device_unregister(pd->dev);
 338}
 339
 340
 341/********************************************************************
 342  /sys/class/pktcdvd/
 343                     add            map block device
 344                     remove         unmap packet dev
 345                     device_map     show mappings
 346 *******************************************************************/
 347
 348static void class_pktcdvd_release(struct class *cls)
 349{
 350	kfree(cls);
 351}
 352
 353static ssize_t device_map_show(struct class *c, struct class_attribute *attr,
 354			       char *data)
 355{
 356	int n = 0;
 357	int idx;
 358	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 359	for (idx = 0; idx < MAX_WRITERS; idx++) {
 360		struct pktcdvd_device *pd = pkt_devs[idx];
 361		if (!pd)
 362			continue;
 363		n += sprintf(data+n, "%s %u:%u %u:%u\n",
 364			pd->name,
 365			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 366			MAJOR(pd->bdev->bd_dev),
 367			MINOR(pd->bdev->bd_dev));
 368	}
 369	mutex_unlock(&ctl_mutex);
 370	return n;
 371}
 372static CLASS_ATTR_RO(device_map);
 373
 374static ssize_t add_store(struct class *c, struct class_attribute *attr,
 375			 const char *buf, size_t count)
 376{
 377	unsigned int major, minor;
 378
 379	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 380		/* pkt_setup_dev() expects caller to hold reference to self */
 381		if (!try_module_get(THIS_MODULE))
 382			return -ENODEV;
 383
 384		pkt_setup_dev(MKDEV(major, minor), NULL);
 385
 386		module_put(THIS_MODULE);
 387
 388		return count;
 389	}
 390
 391	return -EINVAL;
 392}
 393static CLASS_ATTR_WO(add);
 394
 395static ssize_t remove_store(struct class *c, struct class_attribute *attr,
 396			    const char *buf, size_t count)
 397{
 398	unsigned int major, minor;
 399	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 400		pkt_remove_dev(MKDEV(major, minor));
 401		return count;
 402	}
 403	return -EINVAL;
 404}
 405static CLASS_ATTR_WO(remove);
 406
 407static struct attribute *class_pktcdvd_attrs[] = {
 408	&class_attr_add.attr,
 409	&class_attr_remove.attr,
 410	&class_attr_device_map.attr,
 411	NULL,
 412};
 413ATTRIBUTE_GROUPS(class_pktcdvd);
 414
 415static int pkt_sysfs_init(void)
 416{
 417	int ret = 0;
 418
 419	/*
 420	 * create control files in sysfs
 421	 * /sys/class/pktcdvd/...
 422	 */
 423	class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 424	if (!class_pktcdvd)
 425		return -ENOMEM;
 426	class_pktcdvd->name = DRIVER_NAME;
 427	class_pktcdvd->owner = THIS_MODULE;
 428	class_pktcdvd->class_release = class_pktcdvd_release;
 429	class_pktcdvd->class_groups = class_pktcdvd_groups;
 430	ret = class_register(class_pktcdvd);
 431	if (ret) {
 432		kfree(class_pktcdvd);
 433		class_pktcdvd = NULL;
 434		pr_err("failed to create class pktcdvd\n");
 435		return ret;
 436	}
 437	return 0;
 438}
 439
 440static void pkt_sysfs_cleanup(void)
 441{
 442	if (class_pktcdvd)
 443		class_destroy(class_pktcdvd);
 444	class_pktcdvd = NULL;
 445}
 446
 447/********************************************************************
 448  entries in debugfs
 449
 450  /sys/kernel/debug/pktcdvd[0-7]/
 451			info
 452
 453 *******************************************************************/
 454
 455static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 456{
 457	return pkt_seq_show(m, p);
 458}
 459
 460static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 461{
 462	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 463}
 464
 465static const struct file_operations debug_fops = {
 466	.open		= pkt_debugfs_fops_open,
 467	.read		= seq_read,
 468	.llseek		= seq_lseek,
 469	.release	= single_release,
 470	.owner		= THIS_MODULE,
 471};
 472
 473static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 474{
 475	if (!pkt_debugfs_root)
 476		return;
 477	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 478	if (!pd->dfs_d_root)
 479		return;
 480
 481	pd->dfs_f_info = debugfs_create_file("info", 0444,
 482					     pd->dfs_d_root, pd, &debug_fops);
 483}
 484
 485static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 486{
 487	if (!pkt_debugfs_root)
 488		return;
 489	debugfs_remove(pd->dfs_f_info);
 490	debugfs_remove(pd->dfs_d_root);
 491	pd->dfs_f_info = NULL;
 492	pd->dfs_d_root = NULL;
 493}
 494
 495static void pkt_debugfs_init(void)
 496{
 497	pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 498}
 499
 500static void pkt_debugfs_cleanup(void)
 501{
 502	debugfs_remove(pkt_debugfs_root);
 503	pkt_debugfs_root = NULL;
 504}
 505
 506/* ----------------------------------------------------------*/
 507
 508
 509static void pkt_bio_finished(struct pktcdvd_device *pd)
 510{
 511	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 512	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 513		pkt_dbg(2, pd, "queue empty\n");
 514		atomic_set(&pd->iosched.attention, 1);
 515		wake_up(&pd->wqueue);
 516	}
 517}
 518
 519/*
 520 * Allocate a packet_data struct
 521 */
 522static struct packet_data *pkt_alloc_packet_data(int frames)
 523{
 524	int i;
 525	struct packet_data *pkt;
 526
 527	pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 528	if (!pkt)
 529		goto no_pkt;
 530
 531	pkt->frames = frames;
 532	pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
 533	if (!pkt->w_bio)
 534		goto no_bio;
 535
 536	for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 537		pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 538		if (!pkt->pages[i])
 539			goto no_page;
 540	}
 541
 542	spin_lock_init(&pkt->lock);
 543	bio_list_init(&pkt->orig_bios);
 544
 545	for (i = 0; i < frames; i++) {
 546		struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
 547		if (!bio)
 548			goto no_rd_bio;
 549
 550		pkt->r_bios[i] = bio;
 551	}
 552
 553	return pkt;
 554
 555no_rd_bio:
 556	for (i = 0; i < frames; i++) {
 557		struct bio *bio = pkt->r_bios[i];
 558		if (bio)
 559			bio_put(bio);
 560	}
 561
 562no_page:
 563	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 564		if (pkt->pages[i])
 565			__free_page(pkt->pages[i]);
 566	bio_put(pkt->w_bio);
 567no_bio:
 568	kfree(pkt);
 569no_pkt:
 570	return NULL;
 571}
 572
 573/*
 574 * Free a packet_data struct
 575 */
 576static void pkt_free_packet_data(struct packet_data *pkt)
 577{
 578	int i;
 579
 580	for (i = 0; i < pkt->frames; i++) {
 581		struct bio *bio = pkt->r_bios[i];
 582		if (bio)
 583			bio_put(bio);
 584	}
 585	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 586		__free_page(pkt->pages[i]);
 587	bio_put(pkt->w_bio);
 588	kfree(pkt);
 589}
 590
 591static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 592{
 593	struct packet_data *pkt, *next;
 594
 595	BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 596
 597	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 598		pkt_free_packet_data(pkt);
 599	}
 600	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 601}
 602
 603static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 604{
 605	struct packet_data *pkt;
 606
 607	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 608
 609	while (nr_packets > 0) {
 610		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 611		if (!pkt) {
 612			pkt_shrink_pktlist(pd);
 613			return 0;
 614		}
 615		pkt->id = nr_packets;
 616		pkt->pd = pd;
 617		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 618		nr_packets--;
 619	}
 620	return 1;
 621}
 622
 623static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 624{
 625	struct rb_node *n = rb_next(&node->rb_node);
 626	if (!n)
 627		return NULL;
 628	return rb_entry(n, struct pkt_rb_node, rb_node);
 629}
 630
 631static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 632{
 633	rb_erase(&node->rb_node, &pd->bio_queue);
 634	mempool_free(node, &pd->rb_pool);
 635	pd->bio_queue_size--;
 636	BUG_ON(pd->bio_queue_size < 0);
 637}
 638
 639/*
 640 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 641 */
 642static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 643{
 644	struct rb_node *n = pd->bio_queue.rb_node;
 645	struct rb_node *next;
 646	struct pkt_rb_node *tmp;
 647
 648	if (!n) {
 649		BUG_ON(pd->bio_queue_size > 0);
 650		return NULL;
 651	}
 652
 653	for (;;) {
 654		tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 655		if (s <= tmp->bio->bi_iter.bi_sector)
 656			next = n->rb_left;
 657		else
 658			next = n->rb_right;
 659		if (!next)
 660			break;
 661		n = next;
 662	}
 663
 664	if (s > tmp->bio->bi_iter.bi_sector) {
 665		tmp = pkt_rbtree_next(tmp);
 666		if (!tmp)
 667			return NULL;
 668	}
 669	BUG_ON(s > tmp->bio->bi_iter.bi_sector);
 670	return tmp;
 671}
 672
 673/*
 674 * Insert a node into the pd->bio_queue rb tree.
 675 */
 676static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 677{
 678	struct rb_node **p = &pd->bio_queue.rb_node;
 679	struct rb_node *parent = NULL;
 680	sector_t s = node->bio->bi_iter.bi_sector;
 681	struct pkt_rb_node *tmp;
 682
 683	while (*p) {
 684		parent = *p;
 685		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 686		if (s < tmp->bio->bi_iter.bi_sector)
 687			p = &(*p)->rb_left;
 688		else
 689			p = &(*p)->rb_right;
 690	}
 691	rb_link_node(&node->rb_node, parent, p);
 692	rb_insert_color(&node->rb_node, &pd->bio_queue);
 693	pd->bio_queue_size++;
 694}
 695
 696/*
 697 * Send a packet_command to the underlying block device and
 698 * wait for completion.
 699 */
 700static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 701{
 702	struct request_queue *q = bdev_get_queue(pd->bdev);
 
 703	struct request *rq;
 704	int ret = 0;
 705
 706	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 707			     REQ_OP_SCSI_OUT : REQ_OP_SCSI_IN, 0);
 708	if (IS_ERR(rq))
 709		return PTR_ERR(rq);
 
 710
 711	if (cgc->buflen) {
 712		ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
 713				      GFP_NOIO);
 714		if (ret)
 715			goto out;
 716	}
 717
 718	scsi_req(rq)->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 719	memcpy(scsi_req(rq)->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 720
 721	rq->timeout = 60*HZ;
 722	if (cgc->quiet)
 723		rq->rq_flags |= RQF_QUIET;
 724
 725	blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 726	if (scsi_req(rq)->result)
 727		ret = -EIO;
 728out:
 729	blk_put_request(rq);
 730	return ret;
 731}
 732
 733static const char *sense_key_string(__u8 index)
 734{
 735	static const char * const info[] = {
 736		"No sense", "Recovered error", "Not ready",
 737		"Medium error", "Hardware error", "Illegal request",
 738		"Unit attention", "Data protect", "Blank check",
 739	};
 740
 741	return index < ARRAY_SIZE(info) ? info[index] : "INVALID";
 742}
 743
 744/*
 745 * A generic sense dump / resolve mechanism should be implemented across
 746 * all ATAPI + SCSI devices.
 747 */
 748static void pkt_dump_sense(struct pktcdvd_device *pd,
 749			   struct packet_command *cgc)
 750{
 751	struct scsi_sense_hdr *sshdr = cgc->sshdr;
 752
 753	if (sshdr)
 754		pkt_err(pd, "%*ph - sense %02x.%02x.%02x (%s)\n",
 755			CDROM_PACKET_SIZE, cgc->cmd,
 756			sshdr->sense_key, sshdr->asc, sshdr->ascq,
 757			sense_key_string(sshdr->sense_key));
 758	else
 759		pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
 760}
 761
 762/*
 763 * flush the drive cache to media
 764 */
 765static int pkt_flush_cache(struct pktcdvd_device *pd)
 766{
 767	struct packet_command cgc;
 768
 769	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 770	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 771	cgc.quiet = 1;
 772
 773	/*
 774	 * the IMMED bit -- we default to not setting it, although that
 775	 * would allow a much faster close, this is safer
 776	 */
 777#if 0
 778	cgc.cmd[1] = 1 << 1;
 779#endif
 780	return pkt_generic_packet(pd, &cgc);
 781}
 782
 783/*
 784 * speed is given as the normal factor, e.g. 4 for 4x
 785 */
 786static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 787				unsigned write_speed, unsigned read_speed)
 788{
 789	struct packet_command cgc;
 790	struct scsi_sense_hdr sshdr;
 791	int ret;
 792
 793	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 794	cgc.sshdr = &sshdr;
 795	cgc.cmd[0] = GPCMD_SET_SPEED;
 796	cgc.cmd[2] = (read_speed >> 8) & 0xff;
 797	cgc.cmd[3] = read_speed & 0xff;
 798	cgc.cmd[4] = (write_speed >> 8) & 0xff;
 799	cgc.cmd[5] = write_speed & 0xff;
 800
 801	ret = pkt_generic_packet(pd, &cgc);
 802	if (ret)
 803		pkt_dump_sense(pd, &cgc);
 804
 805	return ret;
 806}
 807
 808/*
 809 * Queue a bio for processing by the low-level CD device. Must be called
 810 * from process context.
 811 */
 812static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 813{
 814	spin_lock(&pd->iosched.lock);
 815	if (bio_data_dir(bio) == READ)
 816		bio_list_add(&pd->iosched.read_queue, bio);
 817	else
 818		bio_list_add(&pd->iosched.write_queue, bio);
 819	spin_unlock(&pd->iosched.lock);
 820
 821	atomic_set(&pd->iosched.attention, 1);
 822	wake_up(&pd->wqueue);
 823}
 824
 825/*
 826 * Process the queued read/write requests. This function handles special
 827 * requirements for CDRW drives:
 828 * - A cache flush command must be inserted before a read request if the
 829 *   previous request was a write.
 830 * - Switching between reading and writing is slow, so don't do it more often
 831 *   than necessary.
 832 * - Optimize for throughput at the expense of latency. This means that streaming
 833 *   writes will never be interrupted by a read, but if the drive has to seek
 834 *   before the next write, switch to reading instead if there are any pending
 835 *   read requests.
 836 * - Set the read speed according to current usage pattern. When only reading
 837 *   from the device, it's best to use the highest possible read speed, but
 838 *   when switching often between reading and writing, it's better to have the
 839 *   same read and write speeds.
 840 */
 841static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 842{
 843
 844	if (atomic_read(&pd->iosched.attention) == 0)
 845		return;
 846	atomic_set(&pd->iosched.attention, 0);
 847
 848	for (;;) {
 849		struct bio *bio;
 850		int reads_queued, writes_queued;
 851
 852		spin_lock(&pd->iosched.lock);
 853		reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 854		writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 855		spin_unlock(&pd->iosched.lock);
 856
 857		if (!reads_queued && !writes_queued)
 858			break;
 859
 860		if (pd->iosched.writing) {
 861			int need_write_seek = 1;
 862			spin_lock(&pd->iosched.lock);
 863			bio = bio_list_peek(&pd->iosched.write_queue);
 864			spin_unlock(&pd->iosched.lock);
 865			if (bio && (bio->bi_iter.bi_sector ==
 866				    pd->iosched.last_write))
 867				need_write_seek = 0;
 868			if (need_write_seek && reads_queued) {
 869				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 870					pkt_dbg(2, pd, "write, waiting\n");
 871					break;
 872				}
 873				pkt_flush_cache(pd);
 874				pd->iosched.writing = 0;
 875			}
 876		} else {
 877			if (!reads_queued && writes_queued) {
 878				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 879					pkt_dbg(2, pd, "read, waiting\n");
 880					break;
 881				}
 882				pd->iosched.writing = 1;
 883			}
 884		}
 885
 886		spin_lock(&pd->iosched.lock);
 887		if (pd->iosched.writing)
 888			bio = bio_list_pop(&pd->iosched.write_queue);
 889		else
 890			bio = bio_list_pop(&pd->iosched.read_queue);
 891		spin_unlock(&pd->iosched.lock);
 892
 893		if (!bio)
 894			continue;
 895
 896		if (bio_data_dir(bio) == READ)
 897			pd->iosched.successive_reads +=
 898				bio->bi_iter.bi_size >> 10;
 899		else {
 900			pd->iosched.successive_reads = 0;
 901			pd->iosched.last_write = bio_end_sector(bio);
 902		}
 903		if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 904			if (pd->read_speed == pd->write_speed) {
 905				pd->read_speed = MAX_SPEED;
 906				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 907			}
 908		} else {
 909			if (pd->read_speed != pd->write_speed) {
 910				pd->read_speed = pd->write_speed;
 911				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 912			}
 913		}
 914
 915		atomic_inc(&pd->cdrw.pending_bios);
 916		submit_bio_noacct(bio);
 917	}
 918}
 919
 920/*
 921 * Special care is needed if the underlying block device has a small
 922 * max_phys_segments value.
 923 */
 924static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 925{
 926	if ((pd->settings.size << 9) / CD_FRAMESIZE
 927	    <= queue_max_segments(q)) {
 928		/*
 929		 * The cdrom device can handle one segment/frame
 930		 */
 931		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 932		return 0;
 933	} else if ((pd->settings.size << 9) / PAGE_SIZE
 934		   <= queue_max_segments(q)) {
 935		/*
 936		 * We can handle this case at the expense of some extra memory
 937		 * copies during write operations
 938		 */
 939		set_bit(PACKET_MERGE_SEGS, &pd->flags);
 940		return 0;
 941	} else {
 942		pkt_err(pd, "cdrom max_phys_segments too small\n");
 943		return -EIO;
 944	}
 945}
 946
 947static void pkt_end_io_read(struct bio *bio)
 948{
 949	struct packet_data *pkt = bio->bi_private;
 950	struct pktcdvd_device *pd = pkt->pd;
 951	BUG_ON(!pd);
 952
 953	pkt_dbg(2, pd, "bio=%p sec0=%llx sec=%llx err=%d\n",
 954		bio, (unsigned long long)pkt->sector,
 955		(unsigned long long)bio->bi_iter.bi_sector, bio->bi_status);
 956
 957	if (bio->bi_status)
 958		atomic_inc(&pkt->io_errors);
 
 959	if (atomic_dec_and_test(&pkt->io_wait)) {
 960		atomic_inc(&pkt->run_sm);
 961		wake_up(&pd->wqueue);
 962	}
 963	pkt_bio_finished(pd);
 964}
 965
 966static void pkt_end_io_packet_write(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	pkt_dbg(2, pd, "id=%d, err=%d\n", pkt->id, bio->bi_status);
 973
 974	pd->stats.pkt_ended++;
 975
 
 976	pkt_bio_finished(pd);
 977	atomic_dec(&pkt->io_wait);
 978	atomic_inc(&pkt->run_sm);
 979	wake_up(&pd->wqueue);
 980}
 981
 982/*
 983 * Schedule reads for the holes in a packet
 984 */
 985static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 986{
 987	int frames_read = 0;
 988	struct bio *bio;
 989	int f;
 990	char written[PACKET_MAX_SIZE];
 991
 992	BUG_ON(bio_list_empty(&pkt->orig_bios));
 993
 994	atomic_set(&pkt->io_wait, 0);
 995	atomic_set(&pkt->io_errors, 0);
 996
 997	/*
 998	 * Figure out which frames we need to read before we can write.
 999	 */
1000	memset(written, 0, sizeof(written));
1001	spin_lock(&pkt->lock);
1002	bio_list_for_each(bio, &pkt->orig_bios) {
1003		int first_frame = (bio->bi_iter.bi_sector - pkt->sector) /
1004			(CD_FRAMESIZE >> 9);
1005		int num_frames = bio->bi_iter.bi_size / CD_FRAMESIZE;
1006		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1007		BUG_ON(first_frame < 0);
1008		BUG_ON(first_frame + num_frames > pkt->frames);
1009		for (f = first_frame; f < first_frame + num_frames; f++)
1010			written[f] = 1;
1011	}
1012	spin_unlock(&pkt->lock);
1013
1014	if (pkt->cache_valid) {
1015		pkt_dbg(2, pd, "zone %llx cached\n",
1016			(unsigned long long)pkt->sector);
1017		goto out_account;
1018	}
1019
1020	/*
1021	 * Schedule reads for missing parts of the packet.
1022	 */
1023	for (f = 0; f < pkt->frames; f++) {
1024		int p, offset;
1025
1026		if (written[f])
1027			continue;
1028
1029		bio = pkt->r_bios[f];
1030		bio_reset(bio);
1031		bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1032		bio_set_dev(bio, pd->bdev);
1033		bio->bi_end_io = pkt_end_io_read;
1034		bio->bi_private = pkt;
1035
1036		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1037		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1038		pkt_dbg(2, pd, "Adding frame %d, page:%p offs:%d\n",
1039			f, pkt->pages[p], offset);
1040		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1041			BUG();
1042
1043		atomic_inc(&pkt->io_wait);
1044		bio_set_op_attrs(bio, REQ_OP_READ, 0);
1045		pkt_queue_bio(pd, bio);
1046		frames_read++;
1047	}
1048
1049out_account:
1050	pkt_dbg(2, pd, "need %d frames for zone %llx\n",
1051		frames_read, (unsigned long long)pkt->sector);
1052	pd->stats.pkt_started++;
1053	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1054}
1055
1056/*
1057 * Find a packet matching zone, or the least recently used packet if
1058 * there is no match.
1059 */
1060static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1061{
1062	struct packet_data *pkt;
1063
1064	list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1065		if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1066			list_del_init(&pkt->list);
1067			if (pkt->sector != zone)
1068				pkt->cache_valid = 0;
1069			return pkt;
1070		}
1071	}
1072	BUG();
1073	return NULL;
1074}
1075
1076static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1077{
1078	if (pkt->cache_valid) {
1079		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1080	} else {
1081		list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1082	}
1083}
1084
1085/*
1086 * recover a failed write, query for relocation if possible
1087 *
1088 * returns 1 if recovery is possible, or 0 if not
1089 *
1090 */
1091static int pkt_start_recovery(struct packet_data *pkt)
1092{
1093	/*
1094	 * FIXME. We need help from the file system to implement
1095	 * recovery handling.
1096	 */
1097	return 0;
1098#if 0
1099	struct request *rq = pkt->rq;
1100	struct pktcdvd_device *pd = rq->rq_disk->private_data;
1101	struct block_device *pkt_bdev;
1102	struct super_block *sb = NULL;
1103	unsigned long old_block, new_block;
1104	sector_t new_sector;
1105
1106	pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1107	if (pkt_bdev) {
1108		sb = get_super(pkt_bdev);
1109		bdput(pkt_bdev);
1110	}
1111
1112	if (!sb)
1113		return 0;
1114
1115	if (!sb->s_op->relocate_blocks)
1116		goto out;
1117
1118	old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1119	if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1120		goto out;
1121
1122	new_sector = new_block * (CD_FRAMESIZE >> 9);
1123	pkt->sector = new_sector;
1124
1125	bio_reset(pkt->bio);
1126	bio_set_dev(pkt->bio, pd->bdev);
1127	bio_set_op_attrs(pkt->bio, REQ_OP_WRITE, 0);
1128	pkt->bio->bi_iter.bi_sector = new_sector;
1129	pkt->bio->bi_iter.bi_size = pkt->frames * CD_FRAMESIZE;
1130	pkt->bio->bi_vcnt = pkt->frames;
1131
1132	pkt->bio->bi_end_io = pkt_end_io_packet_write;
1133	pkt->bio->bi_private = pkt;
1134
1135	drop_super(sb);
1136	return 1;
1137
1138out:
1139	drop_super(sb);
1140	return 0;
1141#endif
1142}
1143
1144static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1145{
1146#if PACKET_DEBUG > 1
1147	static const char *state_name[] = {
1148		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1149	};
1150	enum packet_data_state old_state = pkt->state;
1151	pkt_dbg(2, pd, "pkt %2d : s=%6llx %s -> %s\n",
1152		pkt->id, (unsigned long long)pkt->sector,
1153		state_name[old_state], state_name[state]);
1154#endif
1155	pkt->state = state;
1156}
1157
1158/*
1159 * Scan the work queue to see if we can start a new packet.
1160 * returns non-zero if any work was done.
1161 */
1162static int pkt_handle_queue(struct pktcdvd_device *pd)
1163{
1164	struct packet_data *pkt, *p;
1165	struct bio *bio = NULL;
1166	sector_t zone = 0; /* Suppress gcc warning */
1167	struct pkt_rb_node *node, *first_node;
1168	struct rb_node *n;
1169	int wakeup;
1170
1171	atomic_set(&pd->scan_queue, 0);
1172
1173	if (list_empty(&pd->cdrw.pkt_free_list)) {
1174		pkt_dbg(2, pd, "no pkt\n");
1175		return 0;
1176	}
1177
1178	/*
1179	 * Try to find a zone we are not already working on.
1180	 */
1181	spin_lock(&pd->lock);
1182	first_node = pkt_rbtree_find(pd, pd->current_sector);
1183	if (!first_node) {
1184		n = rb_first(&pd->bio_queue);
1185		if (n)
1186			first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1187	}
1188	node = first_node;
1189	while (node) {
1190		bio = node->bio;
1191		zone = get_zone(bio->bi_iter.bi_sector, pd);
1192		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1193			if (p->sector == zone) {
1194				bio = NULL;
1195				goto try_next_bio;
1196			}
1197		}
1198		break;
1199try_next_bio:
1200		node = pkt_rbtree_next(node);
1201		if (!node) {
1202			n = rb_first(&pd->bio_queue);
1203			if (n)
1204				node = rb_entry(n, struct pkt_rb_node, rb_node);
1205		}
1206		if (node == first_node)
1207			node = NULL;
1208	}
1209	spin_unlock(&pd->lock);
1210	if (!bio) {
1211		pkt_dbg(2, pd, "no bio\n");
1212		return 0;
1213	}
1214
1215	pkt = pkt_get_packet_data(pd, zone);
1216
1217	pd->current_sector = zone + pd->settings.size;
1218	pkt->sector = zone;
1219	BUG_ON(pkt->frames != pd->settings.size >> 2);
1220	pkt->write_size = 0;
1221
1222	/*
1223	 * Scan work queue for bios in the same zone and link them
1224	 * to this packet.
1225	 */
1226	spin_lock(&pd->lock);
1227	pkt_dbg(2, pd, "looking for zone %llx\n", (unsigned long long)zone);
1228	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1229		bio = node->bio;
1230		pkt_dbg(2, pd, "found zone=%llx\n", (unsigned long long)
1231			get_zone(bio->bi_iter.bi_sector, pd));
1232		if (get_zone(bio->bi_iter.bi_sector, pd) != zone)
1233			break;
1234		pkt_rbtree_erase(pd, node);
1235		spin_lock(&pkt->lock);
1236		bio_list_add(&pkt->orig_bios, bio);
1237		pkt->write_size += bio->bi_iter.bi_size / CD_FRAMESIZE;
1238		spin_unlock(&pkt->lock);
1239	}
1240	/* check write congestion marks, and if bio_queue_size is
1241	   below, wake up any waiters */
1242	wakeup = (pd->write_congestion_on > 0
1243	 		&& pd->bio_queue_size <= pd->write_congestion_off);
1244	spin_unlock(&pd->lock);
1245	if (wakeup) {
1246		clear_bdi_congested(pd->disk->queue->backing_dev_info,
1247					BLK_RW_ASYNC);
1248	}
 
1249
1250	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1251	pkt_set_state(pkt, PACKET_WAITING_STATE);
1252	atomic_set(&pkt->run_sm, 1);
1253
1254	spin_lock(&pd->cdrw.active_list_lock);
1255	list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1256	spin_unlock(&pd->cdrw.active_list_lock);
1257
1258	return 1;
1259}
1260
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1261/*
1262 * Assemble a bio to write one packet and queue the bio for processing
1263 * by the underlying block device.
1264 */
1265static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1266{
1267	int f;
1268
1269	bio_reset(pkt->w_bio);
 
1270	pkt->w_bio->bi_iter.bi_sector = pkt->sector;
1271	bio_set_dev(pkt->w_bio, pd->bdev);
1272	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1273	pkt->w_bio->bi_private = pkt;
1274
1275	/* XXX: locking? */
1276	for (f = 0; f < pkt->frames; f++) {
1277		struct page *page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1278		unsigned offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1279
1280		if (!bio_add_page(pkt->w_bio, page, CD_FRAMESIZE, offset))
1281			BUG();
1282	}
1283	pkt_dbg(2, pd, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
1284
1285	/*
1286	 * Fill-in bvec with data from orig_bios.
1287	 */
1288	spin_lock(&pkt->lock);
1289	bio_list_copy_data(pkt->w_bio, pkt->orig_bios.head);
1290
1291	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1292	spin_unlock(&pkt->lock);
1293
1294	pkt_dbg(2, pd, "Writing %d frames for zone %llx\n",
1295		pkt->write_size, (unsigned long long)pkt->sector);
1296
1297	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames))
1298		pkt->cache_valid = 1;
1299	else
1300		pkt->cache_valid = 0;
1301
1302	/* Start the write request */
1303	atomic_set(&pkt->io_wait, 1);
1304	bio_set_op_attrs(pkt->w_bio, REQ_OP_WRITE, 0);
1305	pkt_queue_bio(pd, pkt->w_bio);
1306}
1307
1308static void pkt_finish_packet(struct packet_data *pkt, blk_status_t status)
1309{
1310	struct bio *bio;
1311
1312	if (status)
1313		pkt->cache_valid = 0;
1314
1315	/* Finish all bios corresponding to this packet */
1316	while ((bio = bio_list_pop(&pkt->orig_bios))) {
1317		bio->bi_status = status;
1318		bio_endio(bio);
1319	}
1320}
1321
1322static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1323{
1324	pkt_dbg(2, pd, "pkt %d\n", pkt->id);
1325
1326	for (;;) {
1327		switch (pkt->state) {
1328		case PACKET_WAITING_STATE:
1329			if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1330				return;
1331
1332			pkt->sleep_time = 0;
1333			pkt_gather_data(pd, pkt);
1334			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1335			break;
1336
1337		case PACKET_READ_WAIT_STATE:
1338			if (atomic_read(&pkt->io_wait) > 0)
1339				return;
1340
1341			if (atomic_read(&pkt->io_errors) > 0) {
1342				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1343			} else {
1344				pkt_start_write(pd, pkt);
1345			}
1346			break;
1347
1348		case PACKET_WRITE_WAIT_STATE:
1349			if (atomic_read(&pkt->io_wait) > 0)
1350				return;
1351
1352			if (!pkt->w_bio->bi_status) {
1353				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1354			} else {
1355				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1356			}
1357			break;
1358
1359		case PACKET_RECOVERY_STATE:
1360			if (pkt_start_recovery(pkt)) {
1361				pkt_start_write(pd, pkt);
1362			} else {
1363				pkt_dbg(2, pd, "No recovery possible\n");
1364				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1365			}
1366			break;
1367
1368		case PACKET_FINISHED_STATE:
1369			pkt_finish_packet(pkt, pkt->w_bio->bi_status);
1370			return;
1371
1372		default:
1373			BUG();
1374			break;
1375		}
1376	}
1377}
1378
1379static void pkt_handle_packets(struct pktcdvd_device *pd)
1380{
1381	struct packet_data *pkt, *next;
1382
1383	/*
1384	 * Run state machine for active packets
1385	 */
1386	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1387		if (atomic_read(&pkt->run_sm) > 0) {
1388			atomic_set(&pkt->run_sm, 0);
1389			pkt_run_state_machine(pd, pkt);
1390		}
1391	}
1392
1393	/*
1394	 * Move no longer active packets to the free list
1395	 */
1396	spin_lock(&pd->cdrw.active_list_lock);
1397	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1398		if (pkt->state == PACKET_FINISHED_STATE) {
1399			list_del(&pkt->list);
1400			pkt_put_packet_data(pd, pkt);
1401			pkt_set_state(pkt, PACKET_IDLE_STATE);
1402			atomic_set(&pd->scan_queue, 1);
1403		}
1404	}
1405	spin_unlock(&pd->cdrw.active_list_lock);
1406}
1407
1408static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1409{
1410	struct packet_data *pkt;
1411	int i;
1412
1413	for (i = 0; i < PACKET_NUM_STATES; i++)
1414		states[i] = 0;
1415
1416	spin_lock(&pd->cdrw.active_list_lock);
1417	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1418		states[pkt->state]++;
1419	}
1420	spin_unlock(&pd->cdrw.active_list_lock);
1421}
1422
1423/*
1424 * kcdrwd is woken up when writes have been queued for one of our
1425 * registered devices
1426 */
1427static int kcdrwd(void *foobar)
1428{
1429	struct pktcdvd_device *pd = foobar;
1430	struct packet_data *pkt;
1431	long min_sleep_time, residue;
1432
1433	set_user_nice(current, MIN_NICE);
1434	set_freezable();
1435
1436	for (;;) {
1437		DECLARE_WAITQUEUE(wait, current);
1438
1439		/*
1440		 * Wait until there is something to do
1441		 */
1442		add_wait_queue(&pd->wqueue, &wait);
1443		for (;;) {
1444			set_current_state(TASK_INTERRUPTIBLE);
1445
1446			/* Check if we need to run pkt_handle_queue */
1447			if (atomic_read(&pd->scan_queue) > 0)
1448				goto work_to_do;
1449
1450			/* Check if we need to run the state machine for some packet */
1451			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1452				if (atomic_read(&pkt->run_sm) > 0)
1453					goto work_to_do;
1454			}
1455
1456			/* Check if we need to process the iosched queues */
1457			if (atomic_read(&pd->iosched.attention) != 0)
1458				goto work_to_do;
1459
1460			/* Otherwise, go to sleep */
1461			if (PACKET_DEBUG > 1) {
1462				int states[PACKET_NUM_STATES];
1463				pkt_count_states(pd, states);
1464				pkt_dbg(2, pd, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1465					states[0], states[1], states[2],
1466					states[3], states[4], states[5]);
1467			}
1468
1469			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1470			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1471				if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1472					min_sleep_time = pkt->sleep_time;
1473			}
1474
1475			pkt_dbg(2, pd, "sleeping\n");
1476			residue = schedule_timeout(min_sleep_time);
1477			pkt_dbg(2, pd, "wake up\n");
1478
1479			/* make swsusp happy with our thread */
1480			try_to_freeze();
1481
1482			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1483				if (!pkt->sleep_time)
1484					continue;
1485				pkt->sleep_time -= min_sleep_time - residue;
1486				if (pkt->sleep_time <= 0) {
1487					pkt->sleep_time = 0;
1488					atomic_inc(&pkt->run_sm);
1489				}
1490			}
1491
1492			if (kthread_should_stop())
1493				break;
1494		}
1495work_to_do:
1496		set_current_state(TASK_RUNNING);
1497		remove_wait_queue(&pd->wqueue, &wait);
1498
1499		if (kthread_should_stop())
1500			break;
1501
1502		/*
1503		 * if pkt_handle_queue returns true, we can queue
1504		 * another request.
1505		 */
1506		while (pkt_handle_queue(pd))
1507			;
1508
1509		/*
1510		 * Handle packet state machine
1511		 */
1512		pkt_handle_packets(pd);
1513
1514		/*
1515		 * Handle iosched queues
1516		 */
1517		pkt_iosched_process_queue(pd);
1518	}
1519
1520	return 0;
1521}
1522
1523static void pkt_print_settings(struct pktcdvd_device *pd)
1524{
1525	pkt_info(pd, "%s packets, %u blocks, Mode-%c disc\n",
1526		 pd->settings.fp ? "Fixed" : "Variable",
1527		 pd->settings.size >> 2,
1528		 pd->settings.block_mode == 8 ? '1' : '2');
1529}
1530
1531static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1532{
1533	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1534
1535	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1536	cgc->cmd[2] = page_code | (page_control << 6);
1537	cgc->cmd[7] = cgc->buflen >> 8;
1538	cgc->cmd[8] = cgc->buflen & 0xff;
1539	cgc->data_direction = CGC_DATA_READ;
1540	return pkt_generic_packet(pd, cgc);
1541}
1542
1543static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1544{
1545	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1546	memset(cgc->buffer, 0, 2);
1547	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1548	cgc->cmd[1] = 0x10;		/* PF */
1549	cgc->cmd[7] = cgc->buflen >> 8;
1550	cgc->cmd[8] = cgc->buflen & 0xff;
1551	cgc->data_direction = CGC_DATA_WRITE;
1552	return pkt_generic_packet(pd, cgc);
1553}
1554
1555static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1556{
1557	struct packet_command cgc;
1558	int ret;
1559
1560	/* set up command and get the disc info */
1561	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1562	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1563	cgc.cmd[8] = cgc.buflen = 2;
1564	cgc.quiet = 1;
1565
1566	ret = pkt_generic_packet(pd, &cgc);
1567	if (ret)
1568		return ret;
1569
1570	/* not all drives have the same disc_info length, so requeue
1571	 * packet with the length the drive tells us it can supply
1572	 */
1573	cgc.buflen = be16_to_cpu(di->disc_information_length) +
1574		     sizeof(di->disc_information_length);
1575
1576	if (cgc.buflen > sizeof(disc_information))
1577		cgc.buflen = sizeof(disc_information);
1578
1579	cgc.cmd[8] = cgc.buflen;
1580	return pkt_generic_packet(pd, &cgc);
1581}
1582
1583static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1584{
1585	struct packet_command cgc;
1586	int ret;
1587
1588	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1589	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1590	cgc.cmd[1] = type & 3;
1591	cgc.cmd[4] = (track & 0xff00) >> 8;
1592	cgc.cmd[5] = track & 0xff;
1593	cgc.cmd[8] = 8;
1594	cgc.quiet = 1;
1595
1596	ret = pkt_generic_packet(pd, &cgc);
1597	if (ret)
1598		return ret;
1599
1600	cgc.buflen = be16_to_cpu(ti->track_information_length) +
1601		     sizeof(ti->track_information_length);
1602
1603	if (cgc.buflen > sizeof(track_information))
1604		cgc.buflen = sizeof(track_information);
1605
1606	cgc.cmd[8] = cgc.buflen;
1607	return pkt_generic_packet(pd, &cgc);
1608}
1609
1610static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1611						long *last_written)
1612{
1613	disc_information di;
1614	track_information ti;
1615	__u32 last_track;
1616	int ret;
1617
1618	ret = pkt_get_disc_info(pd, &di);
1619	if (ret)
1620		return ret;
1621
1622	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1623	ret = pkt_get_track_info(pd, last_track, 1, &ti);
1624	if (ret)
1625		return ret;
1626
1627	/* if this track is blank, try the previous. */
1628	if (ti.blank) {
1629		last_track--;
1630		ret = pkt_get_track_info(pd, last_track, 1, &ti);
1631		if (ret)
1632			return ret;
1633	}
1634
1635	/* if last recorded field is valid, return it. */
1636	if (ti.lra_v) {
1637		*last_written = be32_to_cpu(ti.last_rec_address);
1638	} else {
1639		/* make it up instead */
1640		*last_written = be32_to_cpu(ti.track_start) +
1641				be32_to_cpu(ti.track_size);
1642		if (ti.free_blocks)
1643			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1644	}
1645	return 0;
1646}
1647
1648/*
1649 * write mode select package based on pd->settings
1650 */
1651static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1652{
1653	struct packet_command cgc;
1654	struct scsi_sense_hdr sshdr;
1655	write_param_page *wp;
1656	char buffer[128];
1657	int ret, size;
1658
1659	/* doesn't apply to DVD+RW or DVD-RAM */
1660	if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1661		return 0;
1662
1663	memset(buffer, 0, sizeof(buffer));
1664	init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1665	cgc.sshdr = &sshdr;
1666	ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0);
1667	if (ret) {
1668		pkt_dump_sense(pd, &cgc);
1669		return ret;
1670	}
1671
1672	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1673	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1674	if (size > sizeof(buffer))
1675		size = sizeof(buffer);
1676
1677	/*
1678	 * now get it all
1679	 */
1680	init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1681	cgc.sshdr = &sshdr;
1682	ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0);
1683	if (ret) {
1684		pkt_dump_sense(pd, &cgc);
1685		return ret;
1686	}
1687
1688	/*
1689	 * write page is offset header + block descriptor length
1690	 */
1691	wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1692
1693	wp->fp = pd->settings.fp;
1694	wp->track_mode = pd->settings.track_mode;
1695	wp->write_type = pd->settings.write_type;
1696	wp->data_block_type = pd->settings.block_mode;
1697
1698	wp->multi_session = 0;
1699
1700#ifdef PACKET_USE_LS
1701	wp->link_size = 7;
1702	wp->ls_v = 1;
1703#endif
1704
1705	if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1706		wp->session_format = 0;
1707		wp->subhdr2 = 0x20;
1708	} else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1709		wp->session_format = 0x20;
1710		wp->subhdr2 = 8;
1711#if 0
1712		wp->mcn[0] = 0x80;
1713		memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1714#endif
1715	} else {
1716		/*
1717		 * paranoia
1718		 */
1719		pkt_err(pd, "write mode wrong %d\n", wp->data_block_type);
1720		return 1;
1721	}
1722	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1723
1724	cgc.buflen = cgc.cmd[8] = size;
1725	ret = pkt_mode_select(pd, &cgc);
1726	if (ret) {
1727		pkt_dump_sense(pd, &cgc);
1728		return ret;
1729	}
1730
1731	pkt_print_settings(pd);
1732	return 0;
1733}
1734
1735/*
1736 * 1 -- we can write to this track, 0 -- we can't
1737 */
1738static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1739{
1740	switch (pd->mmc3_profile) {
1741		case 0x1a: /* DVD+RW */
1742		case 0x12: /* DVD-RAM */
1743			/* The track is always writable on DVD+RW/DVD-RAM */
1744			return 1;
1745		default:
1746			break;
1747	}
1748
1749	if (!ti->packet || !ti->fp)
1750		return 0;
1751
1752	/*
1753	 * "good" settings as per Mt Fuji.
1754	 */
1755	if (ti->rt == 0 && ti->blank == 0)
1756		return 1;
1757
1758	if (ti->rt == 0 && ti->blank == 1)
1759		return 1;
1760
1761	if (ti->rt == 1 && ti->blank == 0)
1762		return 1;
1763
1764	pkt_err(pd, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1765	return 0;
1766}
1767
1768/*
1769 * 1 -- we can write to this disc, 0 -- we can't
1770 */
1771static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1772{
1773	switch (pd->mmc3_profile) {
1774		case 0x0a: /* CD-RW */
1775		case 0xffff: /* MMC3 not supported */
1776			break;
1777		case 0x1a: /* DVD+RW */
1778		case 0x13: /* DVD-RW */
1779		case 0x12: /* DVD-RAM */
1780			return 1;
1781		default:
1782			pkt_dbg(2, pd, "Wrong disc profile (%x)\n",
1783				pd->mmc3_profile);
1784			return 0;
1785	}
1786
1787	/*
1788	 * for disc type 0xff we should probably reserve a new track.
1789	 * but i'm not sure, should we leave this to user apps? probably.
1790	 */
1791	if (di->disc_type == 0xff) {
1792		pkt_notice(pd, "unknown disc - no track?\n");
1793		return 0;
1794	}
1795
1796	if (di->disc_type != 0x20 && di->disc_type != 0) {
1797		pkt_err(pd, "wrong disc type (%x)\n", di->disc_type);
1798		return 0;
1799	}
1800
1801	if (di->erasable == 0) {
1802		pkt_notice(pd, "disc not erasable\n");
1803		return 0;
1804	}
1805
1806	if (di->border_status == PACKET_SESSION_RESERVED) {
1807		pkt_err(pd, "can't write to last track (reserved)\n");
1808		return 0;
1809	}
1810
1811	return 1;
1812}
1813
1814static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1815{
1816	struct packet_command cgc;
1817	unsigned char buf[12];
1818	disc_information di;
1819	track_information ti;
1820	int ret, track;
1821
1822	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1823	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1824	cgc.cmd[8] = 8;
1825	ret = pkt_generic_packet(pd, &cgc);
1826	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1827
1828	memset(&di, 0, sizeof(disc_information));
1829	memset(&ti, 0, sizeof(track_information));
1830
1831	ret = pkt_get_disc_info(pd, &di);
1832	if (ret) {
1833		pkt_err(pd, "failed get_disc\n");
1834		return ret;
1835	}
1836
1837	if (!pkt_writable_disc(pd, &di))
1838		return -EROFS;
1839
1840	pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1841
1842	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1843	ret = pkt_get_track_info(pd, track, 1, &ti);
1844	if (ret) {
1845		pkt_err(pd, "failed get_track\n");
1846		return ret;
1847	}
1848
1849	if (!pkt_writable_track(pd, &ti)) {
1850		pkt_err(pd, "can't write to this track\n");
1851		return -EROFS;
1852	}
1853
1854	/*
1855	 * we keep packet size in 512 byte units, makes it easier to
1856	 * deal with request calculations.
1857	 */
1858	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1859	if (pd->settings.size == 0) {
1860		pkt_notice(pd, "detected zero packet size!\n");
1861		return -ENXIO;
1862	}
1863	if (pd->settings.size > PACKET_MAX_SECTORS) {
1864		pkt_err(pd, "packet size is too big\n");
1865		return -EROFS;
1866	}
1867	pd->settings.fp = ti.fp;
1868	pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1869
1870	if (ti.nwa_v) {
1871		pd->nwa = be32_to_cpu(ti.next_writable);
1872		set_bit(PACKET_NWA_VALID, &pd->flags);
1873	}
1874
1875	/*
1876	 * in theory we could use lra on -RW media as well and just zero
1877	 * blocks that haven't been written yet, but in practice that
1878	 * is just a no-go. we'll use that for -R, naturally.
1879	 */
1880	if (ti.lra_v) {
1881		pd->lra = be32_to_cpu(ti.last_rec_address);
1882		set_bit(PACKET_LRA_VALID, &pd->flags);
1883	} else {
1884		pd->lra = 0xffffffff;
1885		set_bit(PACKET_LRA_VALID, &pd->flags);
1886	}
1887
1888	/*
1889	 * fine for now
1890	 */
1891	pd->settings.link_loss = 7;
1892	pd->settings.write_type = 0;	/* packet */
1893	pd->settings.track_mode = ti.track_mode;
1894
1895	/*
1896	 * mode1 or mode2 disc
1897	 */
1898	switch (ti.data_mode) {
1899		case PACKET_MODE1:
1900			pd->settings.block_mode = PACKET_BLOCK_MODE1;
1901			break;
1902		case PACKET_MODE2:
1903			pd->settings.block_mode = PACKET_BLOCK_MODE2;
1904			break;
1905		default:
1906			pkt_err(pd, "unknown data mode\n");
1907			return -EROFS;
1908	}
1909	return 0;
1910}
1911
1912/*
1913 * enable/disable write caching on drive
1914 */
1915static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
1916						int set)
1917{
1918	struct packet_command cgc;
1919	struct scsi_sense_hdr sshdr;
1920	unsigned char buf[64];
1921	int ret;
1922
1923	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1924	cgc.sshdr = &sshdr;
1925	cgc.buflen = pd->mode_offset + 12;
1926
1927	/*
1928	 * caching mode page might not be there, so quiet this command
1929	 */
1930	cgc.quiet = 1;
1931
1932	ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0);
1933	if (ret)
1934		return ret;
1935
1936	buf[pd->mode_offset + 10] |= (!!set << 2);
1937
1938	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1939	ret = pkt_mode_select(pd, &cgc);
1940	if (ret) {
1941		pkt_err(pd, "write caching control failed\n");
1942		pkt_dump_sense(pd, &cgc);
1943	} else if (!ret && set)
1944		pkt_notice(pd, "enabled write caching\n");
1945	return ret;
1946}
1947
1948static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1949{
1950	struct packet_command cgc;
1951
1952	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1953	cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1954	cgc.cmd[4] = lockflag ? 1 : 0;
1955	return pkt_generic_packet(pd, &cgc);
1956}
1957
1958/*
1959 * Returns drive maximum write speed
1960 */
1961static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1962						unsigned *write_speed)
1963{
1964	struct packet_command cgc;
1965	struct scsi_sense_hdr sshdr;
1966	unsigned char buf[256+18];
1967	unsigned char *cap_buf;
1968	int ret, offset;
1969
1970	cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1971	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1972	cgc.sshdr = &sshdr;
1973
1974	ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1975	if (ret) {
1976		cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1977			     sizeof(struct mode_page_header);
1978		ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1979		if (ret) {
1980			pkt_dump_sense(pd, &cgc);
1981			return ret;
1982		}
1983	}
1984
1985	offset = 20;			    /* Obsoleted field, used by older drives */
1986	if (cap_buf[1] >= 28)
1987		offset = 28;		    /* Current write speed selected */
1988	if (cap_buf[1] >= 30) {
1989		/* If the drive reports at least one "Logical Unit Write
1990		 * Speed Performance Descriptor Block", use the information
1991		 * in the first block. (contains the highest speed)
1992		 */
1993		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1994		if (num_spdb > 0)
1995			offset = 34;
1996	}
1997
1998	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1999	return 0;
2000}
2001
2002/* These tables from cdrecord - I don't have orange book */
2003/* standard speed CD-RW (1-4x) */
2004static char clv_to_speed[16] = {
2005	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2006	   0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2007};
2008/* high speed CD-RW (-10x) */
2009static char hs_clv_to_speed[16] = {
2010	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2011	   0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2012};
2013/* ultra high speed CD-RW */
2014static char us_clv_to_speed[16] = {
2015	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2016	   0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2017};
2018
2019/*
2020 * reads the maximum media speed from ATIP
2021 */
2022static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2023						unsigned *speed)
2024{
2025	struct packet_command cgc;
2026	struct scsi_sense_hdr sshdr;
2027	unsigned char buf[64];
2028	unsigned int size, st, sp;
2029	int ret;
2030
2031	init_cdrom_command(&cgc, buf, 2, 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; /* READ ATIP */
2036	cgc.cmd[8] = 2;
2037	ret = pkt_generic_packet(pd, &cgc);
2038	if (ret) {
2039		pkt_dump_sense(pd, &cgc);
2040		return ret;
2041	}
2042	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2043	if (size > sizeof(buf))
2044		size = sizeof(buf);
2045
2046	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2047	cgc.sshdr = &sshdr;
2048	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2049	cgc.cmd[1] = 2;
2050	cgc.cmd[2] = 4;
2051	cgc.cmd[8] = size;
2052	ret = pkt_generic_packet(pd, &cgc);
2053	if (ret) {
2054		pkt_dump_sense(pd, &cgc);
2055		return ret;
2056	}
2057
2058	if (!(buf[6] & 0x40)) {
2059		pkt_notice(pd, "disc type is not CD-RW\n");
2060		return 1;
2061	}
2062	if (!(buf[6] & 0x4)) {
2063		pkt_notice(pd, "A1 values on media are not valid, maybe not CDRW?\n");
2064		return 1;
2065	}
2066
2067	st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2068
2069	sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2070
2071	/* Info from cdrecord */
2072	switch (st) {
2073		case 0: /* standard speed */
2074			*speed = clv_to_speed[sp];
2075			break;
2076		case 1: /* high speed */
2077			*speed = hs_clv_to_speed[sp];
2078			break;
2079		case 2: /* ultra high speed */
2080			*speed = us_clv_to_speed[sp];
2081			break;
2082		default:
2083			pkt_notice(pd, "unknown disc sub-type %d\n", st);
2084			return 1;
2085	}
2086	if (*speed) {
2087		pkt_info(pd, "maximum media speed: %d\n", *speed);
2088		return 0;
2089	} else {
2090		pkt_notice(pd, "unknown speed %d for sub-type %d\n", sp, st);
2091		return 1;
2092	}
2093}
2094
2095static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2096{
2097	struct packet_command cgc;
2098	struct scsi_sense_hdr sshdr;
2099	int ret;
2100
2101	pkt_dbg(2, pd, "Performing OPC\n");
2102
2103	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2104	cgc.sshdr = &sshdr;
2105	cgc.timeout = 60*HZ;
2106	cgc.cmd[0] = GPCMD_SEND_OPC;
2107	cgc.cmd[1] = 1;
2108	ret = pkt_generic_packet(pd, &cgc);
2109	if (ret)
2110		pkt_dump_sense(pd, &cgc);
2111	return ret;
2112}
2113
2114static int pkt_open_write(struct pktcdvd_device *pd)
2115{
2116	int ret;
2117	unsigned int write_speed, media_write_speed, read_speed;
2118
2119	ret = pkt_probe_settings(pd);
2120	if (ret) {
2121		pkt_dbg(2, pd, "failed probe\n");
2122		return ret;
2123	}
2124
2125	ret = pkt_set_write_settings(pd);
2126	if (ret) {
2127		pkt_dbg(1, pd, "failed saving write settings\n");
2128		return -EIO;
2129	}
2130
2131	pkt_write_caching(pd, USE_WCACHING);
2132
2133	ret = pkt_get_max_speed(pd, &write_speed);
2134	if (ret)
2135		write_speed = 16 * 177;
2136	switch (pd->mmc3_profile) {
2137		case 0x13: /* DVD-RW */
2138		case 0x1a: /* DVD+RW */
2139		case 0x12: /* DVD-RAM */
2140			pkt_dbg(1, pd, "write speed %ukB/s\n", write_speed);
2141			break;
2142		default:
2143			ret = pkt_media_speed(pd, &media_write_speed);
2144			if (ret)
2145				media_write_speed = 16;
2146			write_speed = min(write_speed, media_write_speed * 177);
2147			pkt_dbg(1, pd, "write speed %ux\n", write_speed / 176);
2148			break;
2149	}
2150	read_speed = write_speed;
2151
2152	ret = pkt_set_speed(pd, write_speed, read_speed);
2153	if (ret) {
2154		pkt_dbg(1, pd, "couldn't set write speed\n");
2155		return -EIO;
2156	}
2157	pd->write_speed = write_speed;
2158	pd->read_speed = read_speed;
2159
2160	ret = pkt_perform_opc(pd);
2161	if (ret) {
2162		pkt_dbg(1, pd, "Optimum Power Calibration failed\n");
2163	}
2164
2165	return 0;
2166}
2167
2168/*
2169 * called at open time.
2170 */
2171static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2172{
2173	int ret;
2174	long lba;
2175	struct request_queue *q;
 
2176
2177	/*
2178	 * We need to re-open the cdrom device without O_NONBLOCK to be able
2179	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2180	 * so bdget() can't fail.
2181	 */
2182	bdget(pd->bdev->bd_dev);
2183	ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd);
2184	if (ret)
2185		goto out;
 
2186
2187	ret = pkt_get_last_written(pd, &lba);
2188	if (ret) {
2189		pkt_err(pd, "pkt_get_last_written failed\n");
2190		goto out_putdev;
2191	}
2192
2193	set_capacity(pd->disk, lba << 2);
2194	set_capacity(pd->bdev->bd_disk, lba << 2);
2195	bd_set_size(pd->bdev, (loff_t)lba << 11);
2196
2197	q = bdev_get_queue(pd->bdev);
2198	if (write) {
2199		ret = pkt_open_write(pd);
2200		if (ret)
2201			goto out_putdev;
2202		/*
2203		 * Some CDRW drives can not handle writes larger than one packet,
2204		 * even if the size is a multiple of the packet size.
2205		 */
2206		blk_queue_max_hw_sectors(q, pd->settings.size);
2207		set_bit(PACKET_WRITABLE, &pd->flags);
2208	} else {
2209		pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2210		clear_bit(PACKET_WRITABLE, &pd->flags);
2211	}
2212
2213	ret = pkt_set_segment_merging(pd, q);
2214	if (ret)
2215		goto out_putdev;
2216
2217	if (write) {
2218		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2219			pkt_err(pd, "not enough memory for buffers\n");
2220			ret = -ENOMEM;
2221			goto out_putdev;
2222		}
2223		pkt_info(pd, "%lukB available on disc\n", lba << 1);
2224	}
2225
2226	return 0;
2227
2228out_putdev:
2229	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2230out:
2231	return ret;
2232}
2233
2234/*
2235 * called when the device is closed. makes sure that the device flushes
2236 * the internal cache before we close.
2237 */
2238static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2239{
2240	if (flush && pkt_flush_cache(pd))
2241		pkt_dbg(1, pd, "not flushing cache\n");
2242
2243	pkt_lock_door(pd, 0);
2244
2245	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2246	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2247
2248	pkt_shrink_pktlist(pd);
2249}
2250
2251static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2252{
2253	if (dev_minor >= MAX_WRITERS)
2254		return NULL;
2255
2256	dev_minor = array_index_nospec(dev_minor, MAX_WRITERS);
2257	return pkt_devs[dev_minor];
2258}
2259
2260static int pkt_open(struct block_device *bdev, fmode_t mode)
2261{
2262	struct pktcdvd_device *pd = NULL;
2263	int ret;
2264
2265	mutex_lock(&pktcdvd_mutex);
2266	mutex_lock(&ctl_mutex);
2267	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2268	if (!pd) {
2269		ret = -ENODEV;
2270		goto out;
2271	}
2272	BUG_ON(pd->refcnt < 0);
2273
2274	pd->refcnt++;
2275	if (pd->refcnt > 1) {
2276		if ((mode & FMODE_WRITE) &&
2277		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
2278			ret = -EBUSY;
2279			goto out_dec;
2280		}
2281	} else {
2282		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2283		if (ret)
2284			goto out_dec;
2285		/*
2286		 * needed here as well, since ext2 (among others) may change
2287		 * the blocksize at mount time
2288		 */
2289		set_blocksize(bdev, CD_FRAMESIZE);
2290	}
2291
2292	mutex_unlock(&ctl_mutex);
2293	mutex_unlock(&pktcdvd_mutex);
2294	return 0;
2295
2296out_dec:
2297	pd->refcnt--;
2298out:
2299	mutex_unlock(&ctl_mutex);
2300	mutex_unlock(&pktcdvd_mutex);
2301	return ret;
2302}
2303
2304static void pkt_close(struct gendisk *disk, fmode_t mode)
2305{
2306	struct pktcdvd_device *pd = disk->private_data;
2307
2308	mutex_lock(&pktcdvd_mutex);
2309	mutex_lock(&ctl_mutex);
2310	pd->refcnt--;
2311	BUG_ON(pd->refcnt < 0);
2312	if (pd->refcnt == 0) {
2313		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2314		pkt_release_dev(pd, flush);
2315	}
2316	mutex_unlock(&ctl_mutex);
2317	mutex_unlock(&pktcdvd_mutex);
2318}
2319
2320
2321static void pkt_end_io_read_cloned(struct bio *bio)
2322{
2323	struct packet_stacked_data *psd = bio->bi_private;
2324	struct pktcdvd_device *pd = psd->pd;
2325
2326	psd->bio->bi_status = bio->bi_status;
2327	bio_put(bio);
2328	bio_endio(psd->bio);
2329	mempool_free(psd, &psd_pool);
2330	pkt_bio_finished(pd);
2331}
2332
2333static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio)
2334{
2335	struct bio *cloned_bio = bio_clone_fast(bio, GFP_NOIO, &pkt_bio_set);
 
2336	struct packet_stacked_data *psd = mempool_alloc(&psd_pool, GFP_NOIO);
2337
2338	psd->pd = pd;
2339	psd->bio = bio;
2340	bio_set_dev(cloned_bio, pd->bdev);
2341	cloned_bio->bi_private = psd;
2342	cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2343	pd->stats.secs_r += bio_sectors(bio);
2344	pkt_queue_bio(pd, cloned_bio);
2345}
2346
2347static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
2348{
2349	struct pktcdvd_device *pd = q->queuedata;
2350	sector_t zone;
2351	struct packet_data *pkt;
2352	int was_empty, blocked_bio;
2353	struct pkt_rb_node *node;
2354
2355	zone = get_zone(bio->bi_iter.bi_sector, pd);
2356
2357	/*
2358	 * If we find a matching packet in state WAITING or READ_WAIT, we can
2359	 * just append this bio to that packet.
2360	 */
2361	spin_lock(&pd->cdrw.active_list_lock);
2362	blocked_bio = 0;
2363	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2364		if (pkt->sector == zone) {
2365			spin_lock(&pkt->lock);
2366			if ((pkt->state == PACKET_WAITING_STATE) ||
2367			    (pkt->state == PACKET_READ_WAIT_STATE)) {
2368				bio_list_add(&pkt->orig_bios, bio);
2369				pkt->write_size +=
2370					bio->bi_iter.bi_size / CD_FRAMESIZE;
2371				if ((pkt->write_size >= pkt->frames) &&
2372				    (pkt->state == PACKET_WAITING_STATE)) {
2373					atomic_inc(&pkt->run_sm);
2374					wake_up(&pd->wqueue);
2375				}
2376				spin_unlock(&pkt->lock);
2377				spin_unlock(&pd->cdrw.active_list_lock);
2378				return;
2379			} else {
2380				blocked_bio = 1;
2381			}
2382			spin_unlock(&pkt->lock);
2383		}
2384	}
2385	spin_unlock(&pd->cdrw.active_list_lock);
2386
2387 	/*
2388	 * Test if there is enough room left in the bio work queue
2389	 * (queue size >= congestion on mark).
2390	 * If not, wait till the work queue size is below the congestion off mark.
2391	 */
2392	spin_lock(&pd->lock);
2393	if (pd->write_congestion_on > 0
2394	    && pd->bio_queue_size >= pd->write_congestion_on) {
2395		set_bdi_congested(q->backing_dev_info, BLK_RW_ASYNC);
2396		do {
 
 
 
 
 
 
 
 
2397			spin_unlock(&pd->lock);
2398			congestion_wait(BLK_RW_ASYNC, HZ);
2399			spin_lock(&pd->lock);
2400		} while(pd->bio_queue_size > pd->write_congestion_off);
2401	}
2402	spin_unlock(&pd->lock);
2403
2404	/*
2405	 * No matching packet found. Store the bio in the work queue.
2406	 */
2407	node = mempool_alloc(&pd->rb_pool, GFP_NOIO);
2408	node->bio = bio;
2409	spin_lock(&pd->lock);
2410	BUG_ON(pd->bio_queue_size < 0);
2411	was_empty = (pd->bio_queue_size == 0);
2412	pkt_rbtree_insert(pd, node);
2413	spin_unlock(&pd->lock);
2414
2415	/*
2416	 * Wake up the worker thread.
2417	 */
2418	atomic_set(&pd->scan_queue, 1);
2419	if (was_empty) {
2420		/* This wake_up is required for correct operation */
2421		wake_up(&pd->wqueue);
2422	} else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2423		/*
2424		 * This wake up is not required for correct operation,
2425		 * but improves performance in some cases.
2426		 */
2427		wake_up(&pd->wqueue);
2428	}
2429}
2430
2431static blk_qc_t pkt_submit_bio(struct bio *bio)
2432{
2433	struct pktcdvd_device *pd;
2434	char b[BDEVNAME_SIZE];
2435	struct bio *split;
2436
2437	blk_queue_split(&bio);
2438
2439	pd = bio->bi_disk->queue->queuedata;
2440	if (!pd) {
2441		pr_err("%s incorrect request queue\n", bio_devname(bio, b));
2442		goto end_io;
2443	}
2444
2445	pkt_dbg(2, pd, "start = %6llx stop = %6llx\n",
2446		(unsigned long long)bio->bi_iter.bi_sector,
2447		(unsigned long long)bio_end_sector(bio));
2448
2449	/*
2450	 * Clone READ bios so we can have our own bi_end_io callback.
2451	 */
2452	if (bio_data_dir(bio) == READ) {
2453		pkt_make_request_read(pd, bio);
2454		return BLK_QC_T_NONE;
2455	}
2456
2457	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2458		pkt_notice(pd, "WRITE for ro device (%llu)\n",
2459			   (unsigned long long)bio->bi_iter.bi_sector);
2460		goto end_io;
2461	}
2462
2463	if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) {
2464		pkt_err(pd, "wrong bio size\n");
2465		goto end_io;
2466	}
2467
2468	do {
2469		sector_t zone = get_zone(bio->bi_iter.bi_sector, pd);
2470		sector_t last_zone = get_zone(bio_end_sector(bio) - 1, pd);
2471
2472		if (last_zone != zone) {
2473			BUG_ON(last_zone != zone + pd->settings.size);
2474
2475			split = bio_split(bio, last_zone -
2476					  bio->bi_iter.bi_sector,
2477					  GFP_NOIO, &pkt_bio_set);
2478			bio_chain(split, bio);
2479		} else {
2480			split = bio;
2481		}
2482
2483		pkt_make_request_write(bio->bi_disk->queue, split);
2484	} while (split != bio);
2485
2486	return BLK_QC_T_NONE;
2487end_io:
2488	bio_io_error(bio);
2489	return BLK_QC_T_NONE;
2490}
2491
2492static void pkt_init_queue(struct pktcdvd_device *pd)
2493{
2494	struct request_queue *q = pd->disk->queue;
2495
2496	blk_queue_logical_block_size(q, CD_FRAMESIZE);
2497	blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2498	q->queuedata = pd;
2499}
2500
2501static int pkt_seq_show(struct seq_file *m, void *p)
2502{
2503	struct pktcdvd_device *pd = m->private;
2504	char *msg;
2505	char bdev_buf[BDEVNAME_SIZE];
2506	int states[PACKET_NUM_STATES];
2507
2508	seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2509		   bdevname(pd->bdev, bdev_buf));
2510
2511	seq_printf(m, "\nSettings:\n");
2512	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2513
2514	if (pd->settings.write_type == 0)
2515		msg = "Packet";
2516	else
2517		msg = "Unknown";
2518	seq_printf(m, "\twrite type:\t\t%s\n", msg);
2519
2520	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2521	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2522
2523	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2524
2525	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2526		msg = "Mode 1";
2527	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2528		msg = "Mode 2";
2529	else
2530		msg = "Unknown";
2531	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2532
2533	seq_printf(m, "\nStatistics:\n");
2534	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2535	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2536	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2537	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2538	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2539
2540	seq_printf(m, "\nMisc:\n");
2541	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2542	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2543	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2544	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2545	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2546	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2547
2548	seq_printf(m, "\nQueue state:\n");
2549	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2550	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2551	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2552
2553	pkt_count_states(pd, states);
2554	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2555		   states[0], states[1], states[2], states[3], states[4], states[5]);
2556
2557	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2558			pd->write_congestion_off,
2559			pd->write_congestion_on);
2560	return 0;
2561}
2562
2563static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2564{
2565	int i;
2566	int ret = 0;
2567	char b[BDEVNAME_SIZE];
2568	struct block_device *bdev;
 
2569
2570	if (pd->pkt_dev == dev) {
2571		pkt_err(pd, "recursive setup not allowed\n");
2572		return -EBUSY;
2573	}
2574	for (i = 0; i < MAX_WRITERS; i++) {
2575		struct pktcdvd_device *pd2 = pkt_devs[i];
2576		if (!pd2)
2577			continue;
2578		if (pd2->bdev->bd_dev == dev) {
2579			pkt_err(pd, "%s already setup\n",
2580				bdevname(pd2->bdev, b));
2581			return -EBUSY;
2582		}
2583		if (pd2->pkt_dev == dev) {
2584			pkt_err(pd, "can't chain pktcdvd devices\n");
2585			return -EBUSY;
2586		}
2587	}
2588
2589	bdev = bdget(dev);
2590	if (!bdev)
2591		return -ENOMEM;
2592	ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2593	if (ret)
2594		return ret;
2595	if (!blk_queue_scsi_passthrough(bdev_get_queue(bdev))) {
2596		blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2597		return -EINVAL;
2598	}
 
2599
2600	/* This is safe, since we have a reference from open(). */
2601	__module_get(THIS_MODULE);
2602
2603	pd->bdev = bdev;
2604	set_blocksize(bdev, CD_FRAMESIZE);
2605
2606	pkt_init_queue(pd);
2607
2608	atomic_set(&pd->cdrw.pending_bios, 0);
2609	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2610	if (IS_ERR(pd->cdrw.thread)) {
2611		pkt_err(pd, "can't start kernel thread\n");
2612		ret = -ENOMEM;
2613		goto out_mem;
2614	}
2615
2616	proc_create_single_data(pd->name, 0, pkt_proc, pkt_seq_show, pd);
2617	pkt_dbg(1, pd, "writer mapped to %s\n", bdevname(bdev, b));
2618	return 0;
2619
2620out_mem:
2621	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2622	/* This is safe: open() is still holding a reference. */
2623	module_put(THIS_MODULE);
2624	return ret;
2625}
2626
2627static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2628{
2629	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2630	int ret;
2631
2632	pkt_dbg(2, pd, "cmd %x, dev %d:%d\n",
2633		cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2634
2635	mutex_lock(&pktcdvd_mutex);
2636	switch (cmd) {
2637	case CDROMEJECT:
2638		/*
2639		 * The door gets locked when the device is opened, so we
2640		 * have to unlock it or else the eject command fails.
2641		 */
2642		if (pd->refcnt == 1)
2643			pkt_lock_door(pd, 0);
2644		fallthrough;
2645	/*
2646	 * forward selected CDROM ioctls to CD-ROM, for UDF
2647	 */
2648	case CDROMMULTISESSION:
2649	case CDROMREADTOCENTRY:
2650	case CDROM_LAST_WRITTEN:
2651	case CDROM_SEND_PACKET:
2652	case SCSI_IOCTL_SEND_COMMAND:
2653		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
 
 
 
2654		break;
2655
2656	default:
2657		pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd);
2658		ret = -ENOTTY;
2659	}
2660	mutex_unlock(&pktcdvd_mutex);
2661
2662	return ret;
2663}
2664
2665static unsigned int pkt_check_events(struct gendisk *disk,
2666				     unsigned int clearing)
2667{
2668	struct pktcdvd_device *pd = disk->private_data;
2669	struct gendisk *attached_disk;
2670
2671	if (!pd)
2672		return 0;
2673	if (!pd->bdev)
2674		return 0;
2675	attached_disk = pd->bdev->bd_disk;
2676	if (!attached_disk || !attached_disk->fops->check_events)
2677		return 0;
2678	return attached_disk->fops->check_events(attached_disk, clearing);
2679}
2680
2681static char *pkt_devnode(struct gendisk *disk, umode_t *mode)
2682{
2683	return kasprintf(GFP_KERNEL, "pktcdvd/%s", disk->disk_name);
2684}
2685
2686static const struct block_device_operations pktcdvd_ops = {
2687	.owner =		THIS_MODULE,
2688	.submit_bio =		pkt_submit_bio,
2689	.open =			pkt_open,
2690	.release =		pkt_close,
2691	.ioctl =		pkt_ioctl,
2692	.compat_ioctl =		blkdev_compat_ptr_ioctl,
2693	.check_events =		pkt_check_events,
2694	.devnode =		pkt_devnode,
2695};
2696
2697/*
2698 * Set up mapping from pktcdvd device to CD-ROM device.
2699 */
2700static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2701{
2702	int idx;
2703	int ret = -ENOMEM;
2704	struct pktcdvd_device *pd;
2705	struct gendisk *disk;
2706
2707	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2708
2709	for (idx = 0; idx < MAX_WRITERS; idx++)
2710		if (!pkt_devs[idx])
2711			break;
2712	if (idx == MAX_WRITERS) {
2713		pr_err("max %d writers supported\n", MAX_WRITERS);
2714		ret = -EBUSY;
2715		goto out_mutex;
2716	}
2717
2718	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2719	if (!pd)
2720		goto out_mutex;
2721
2722	ret = mempool_init_kmalloc_pool(&pd->rb_pool, PKT_RB_POOL_SIZE,
2723					sizeof(struct pkt_rb_node));
2724	if (ret)
2725		goto out_mem;
2726
2727	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2728	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2729	spin_lock_init(&pd->cdrw.active_list_lock);
2730
2731	spin_lock_init(&pd->lock);
2732	spin_lock_init(&pd->iosched.lock);
2733	bio_list_init(&pd->iosched.read_queue);
2734	bio_list_init(&pd->iosched.write_queue);
2735	sprintf(pd->name, DRIVER_NAME"%d", idx);
2736	init_waitqueue_head(&pd->wqueue);
2737	pd->bio_queue = RB_ROOT;
2738
2739	pd->write_congestion_on  = write_congestion_on;
2740	pd->write_congestion_off = write_congestion_off;
2741
2742	ret = -ENOMEM;
2743	disk = alloc_disk(1);
2744	if (!disk)
2745		goto out_mem;
2746	pd->disk = disk;
2747	disk->major = pktdev_major;
2748	disk->first_minor = idx;
 
2749	disk->fops = &pktcdvd_ops;
2750	disk->flags = GENHD_FL_REMOVABLE;
2751	strcpy(disk->disk_name, pd->name);
2752	disk->private_data = pd;
2753	disk->queue = blk_alloc_queue(NUMA_NO_NODE);
2754	if (!disk->queue)
2755		goto out_mem2;
2756
2757	pd->pkt_dev = MKDEV(pktdev_major, idx);
2758	ret = pkt_new_dev(pd, dev);
2759	if (ret)
2760		goto out_mem2;
2761
2762	/* inherit events of the host device */
2763	disk->events = pd->bdev->bd_disk->events;
2764
2765	add_disk(disk);
 
 
2766
2767	pkt_sysfs_dev_new(pd);
2768	pkt_debugfs_dev_new(pd);
2769
2770	pkt_devs[idx] = pd;
2771	if (pkt_dev)
2772		*pkt_dev = pd->pkt_dev;
2773
2774	mutex_unlock(&ctl_mutex);
2775	return 0;
2776
2777out_mem2:
2778	put_disk(disk);
2779out_mem:
2780	mempool_exit(&pd->rb_pool);
2781	kfree(pd);
2782out_mutex:
2783	mutex_unlock(&ctl_mutex);
2784	pr_err("setup of pktcdvd device failed\n");
2785	return ret;
2786}
2787
2788/*
2789 * Tear down mapping from pktcdvd device to CD-ROM device.
2790 */
2791static int pkt_remove_dev(dev_t pkt_dev)
2792{
2793	struct pktcdvd_device *pd;
2794	int idx;
2795	int ret = 0;
2796
2797	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2798
2799	for (idx = 0; idx < MAX_WRITERS; idx++) {
2800		pd = pkt_devs[idx];
2801		if (pd && (pd->pkt_dev == pkt_dev))
2802			break;
2803	}
2804	if (idx == MAX_WRITERS) {
2805		pr_debug("dev not setup\n");
2806		ret = -ENXIO;
2807		goto out;
2808	}
2809
2810	if (pd->refcnt > 0) {
2811		ret = -EBUSY;
2812		goto out;
2813	}
2814	if (!IS_ERR(pd->cdrw.thread))
2815		kthread_stop(pd->cdrw.thread);
2816
2817	pkt_devs[idx] = NULL;
2818
2819	pkt_debugfs_dev_remove(pd);
2820	pkt_sysfs_dev_remove(pd);
2821
2822	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2823
2824	remove_proc_entry(pd->name, pkt_proc);
2825	pkt_dbg(1, pd, "writer unmapped\n");
2826
2827	del_gendisk(pd->disk);
2828	blk_cleanup_queue(pd->disk->queue);
2829	put_disk(pd->disk);
2830
2831	mempool_exit(&pd->rb_pool);
2832	kfree(pd);
2833
2834	/* This is safe: open() is still holding a reference. */
2835	module_put(THIS_MODULE);
2836
2837out:
2838	mutex_unlock(&ctl_mutex);
2839	return ret;
2840}
2841
2842static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2843{
2844	struct pktcdvd_device *pd;
2845
2846	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2847
2848	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2849	if (pd) {
2850		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2851		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2852	} else {
2853		ctrl_cmd->dev = 0;
2854		ctrl_cmd->pkt_dev = 0;
2855	}
2856	ctrl_cmd->num_devices = MAX_WRITERS;
2857
2858	mutex_unlock(&ctl_mutex);
2859}
2860
2861static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2862{
2863	void __user *argp = (void __user *)arg;
2864	struct pkt_ctrl_command ctrl_cmd;
2865	int ret = 0;
2866	dev_t pkt_dev = 0;
2867
2868	if (cmd != PACKET_CTRL_CMD)
2869		return -ENOTTY;
2870
2871	if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2872		return -EFAULT;
2873
2874	switch (ctrl_cmd.command) {
2875	case PKT_CTRL_CMD_SETUP:
2876		if (!capable(CAP_SYS_ADMIN))
2877			return -EPERM;
2878		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2879		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2880		break;
2881	case PKT_CTRL_CMD_TEARDOWN:
2882		if (!capable(CAP_SYS_ADMIN))
2883			return -EPERM;
2884		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2885		break;
2886	case PKT_CTRL_CMD_STATUS:
2887		pkt_get_status(&ctrl_cmd);
2888		break;
2889	default:
2890		return -ENOTTY;
2891	}
2892
2893	if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2894		return -EFAULT;
2895	return ret;
2896}
2897
2898#ifdef CONFIG_COMPAT
2899static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2900{
2901	return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2902}
2903#endif
2904
2905static const struct file_operations pkt_ctl_fops = {
2906	.open		= nonseekable_open,
2907	.unlocked_ioctl	= pkt_ctl_ioctl,
2908#ifdef CONFIG_COMPAT
2909	.compat_ioctl	= pkt_ctl_compat_ioctl,
2910#endif
2911	.owner		= THIS_MODULE,
2912	.llseek		= no_llseek,
2913};
2914
2915static struct miscdevice pkt_misc = {
2916	.minor 		= MISC_DYNAMIC_MINOR,
2917	.name  		= DRIVER_NAME,
2918	.nodename	= "pktcdvd/control",
2919	.fops  		= &pkt_ctl_fops
2920};
2921
2922static int __init pkt_init(void)
2923{
2924	int ret;
2925
2926	mutex_init(&ctl_mutex);
2927
2928	ret = mempool_init_kmalloc_pool(&psd_pool, PSD_POOL_SIZE,
2929				    sizeof(struct packet_stacked_data));
2930	if (ret)
2931		return ret;
2932	ret = bioset_init(&pkt_bio_set, BIO_POOL_SIZE, 0, 0);
2933	if (ret) {
2934		mempool_exit(&psd_pool);
2935		return ret;
2936	}
2937
2938	ret = register_blkdev(pktdev_major, DRIVER_NAME);
2939	if (ret < 0) {
2940		pr_err("unable to register block device\n");
2941		goto out2;
2942	}
2943	if (!pktdev_major)
2944		pktdev_major = ret;
2945
2946	ret = pkt_sysfs_init();
2947	if (ret)
2948		goto out;
2949
2950	pkt_debugfs_init();
2951
2952	ret = misc_register(&pkt_misc);
2953	if (ret) {
2954		pr_err("unable to register misc device\n");
2955		goto out_misc;
2956	}
2957
2958	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
2959
2960	return 0;
2961
2962out_misc:
2963	pkt_debugfs_cleanup();
2964	pkt_sysfs_cleanup();
2965out:
2966	unregister_blkdev(pktdev_major, DRIVER_NAME);
2967out2:
2968	mempool_exit(&psd_pool);
2969	bioset_exit(&pkt_bio_set);
2970	return ret;
2971}
2972
2973static void __exit pkt_exit(void)
2974{
2975	remove_proc_entry("driver/"DRIVER_NAME, NULL);
2976	misc_deregister(&pkt_misc);
2977
2978	pkt_debugfs_cleanup();
2979	pkt_sysfs_cleanup();
2980
2981	unregister_blkdev(pktdev_major, DRIVER_NAME);
2982	mempool_exit(&psd_pool);
2983	bioset_exit(&pkt_bio_set);
2984}
2985
2986MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2987MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2988MODULE_LICENSE("GPL");
2989
2990module_init(pkt_init);
2991module_exit(pkt_exit);
v6.2
   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/pktcdvd.h>
  50#include <linux/module.h>
  51#include <linux/types.h>
  52#include <linux/kernel.h>
  53#include <linux/compat.h>
  54#include <linux/kthread.h>
  55#include <linux/errno.h>
  56#include <linux/spinlock.h>
  57#include <linux/file.h>
  58#include <linux/proc_fs.h>
  59#include <linux/seq_file.h>
  60#include <linux/miscdevice.h>
  61#include <linux/freezer.h>
  62#include <linux/mutex.h>
  63#include <linux/slab.h>
  64#include <linux/backing-dev.h>
  65#include <scsi/scsi_cmnd.h>
  66#include <scsi/scsi_ioctl.h>
  67#include <scsi/scsi.h>
  68#include <linux/debugfs.h>
  69#include <linux/device.h>
  70#include <linux/nospec.h>
  71#include <linux/uaccess.h>
  72
  73#define DRIVER_NAME	"pktcdvd"
  74
  75#define pkt_err(pd, fmt, ...)						\
  76	pr_err("%s: " fmt, pd->name, ##__VA_ARGS__)
  77#define pkt_notice(pd, fmt, ...)					\
  78	pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__)
  79#define pkt_info(pd, fmt, ...)						\
  80	pr_info("%s: " fmt, pd->name, ##__VA_ARGS__)
  81
  82#define pkt_dbg(level, pd, fmt, ...)					\
  83do {									\
  84	if (level == 2 && PACKET_DEBUG >= 2)				\
  85		pr_notice("%s: %s():" fmt,				\
  86			  pd->name, __func__, ##__VA_ARGS__);		\
  87	else if (level == 1 && PACKET_DEBUG >= 1)			\
  88		pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__);		\
  89} while (0)
  90
  91#define MAX_SPEED 0xffff
  92
  93static DEFINE_MUTEX(pktcdvd_mutex);
  94static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  95static struct proc_dir_entry *pkt_proc;
  96static int pktdev_major;
  97static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
  98static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
  99static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
 100static mempool_t psd_pool;
 101static struct bio_set pkt_bio_set;
 102
 103static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
 104static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
 105
 106/* forward declaration */
 107static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
 108static int pkt_remove_dev(dev_t pkt_dev);
 109static int pkt_seq_show(struct seq_file *m, void *p);
 110
 111static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
 112{
 113	return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1);
 114}
 115
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 116/**********************************************************
 
 117 * sysfs interface for pktcdvd
 118 * by (C) 2006  Thomas Maier <balagi@justmail.de>
 119 
 
 
 
 
 
 
 120  /sys/class/pktcdvd/pktcdvd[0-7]/
 121                     stat/reset
 122                     stat/packets_started
 123                     stat/packets_finished
 124                     stat/kb_written
 125                     stat/kb_read
 126                     stat/kb_read_gather
 127                     write_queue/size
 128                     write_queue/congestion_off
 129                     write_queue/congestion_on
 130 **********************************************************/
 131
 132static ssize_t packets_started_show(struct device *dev,
 133				    struct device_attribute *attr, char *buf)
 134{
 135	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 
 
 
 
 
 
 
 
 
 
 
 
 136
 137	return sysfs_emit(buf, "%lu\n", pd->stats.pkt_started);
 138}
 139static DEVICE_ATTR_RO(packets_started);
 
 
 
 
 
 
 
 140
 141static ssize_t packets_finished_show(struct device *dev,
 142				     struct device_attribute *attr, char *buf)
 143{
 144	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 
 
 
 
 145
 146	return sysfs_emit(buf, "%lu\n", pd->stats.pkt_ended);
 147}
 148static DEVICE_ATTR_RO(packets_finished);
 149
 150static ssize_t kb_written_show(struct device *dev,
 151			       struct device_attribute *attr, char *buf)
 152{
 153	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 154
 155	return sysfs_emit(buf, "%lu\n", pd->stats.secs_w >> 1);
 156}
 157static DEVICE_ATTR_RO(kb_written);
 158
 159static ssize_t kb_read_show(struct device *dev,
 160			    struct device_attribute *attr, char *buf)
 161{
 162	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 163
 164	return sysfs_emit(buf, "%lu\n", pd->stats.secs_r >> 1);
 165}
 166static DEVICE_ATTR_RO(kb_read);
 
 
 167
 168static ssize_t kb_read_gather_show(struct device *dev,
 169				   struct device_attribute *attr, char *buf)
 170{
 171	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 
 172
 173	return sysfs_emit(buf, "%lu\n", pd->stats.secs_rg >> 1);
 174}
 175static DEVICE_ATTR_RO(kb_read_gather);
 176
 177static ssize_t reset_store(struct device *dev, struct device_attribute *attr,
 178			   const char *buf, size_t len)
 179{
 180	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 181
 182	if (len > 0) {
 183		pd->stats.pkt_started = 0;
 184		pd->stats.pkt_ended = 0;
 185		pd->stats.secs_w = 0;
 186		pd->stats.secs_rg = 0;
 187		pd->stats.secs_r = 0;
 188	}
 189	return len;
 190}
 191static DEVICE_ATTR_WO(reset);
 192
 193static struct attribute *pkt_stat_attrs[] = {
 194	&dev_attr_packets_finished.attr,
 195	&dev_attr_packets_started.attr,
 196	&dev_attr_kb_read.attr,
 197	&dev_attr_kb_written.attr,
 198	&dev_attr_kb_read_gather.attr,
 199	&dev_attr_reset.attr,
 200	NULL,
 201};
 202
 203static const struct attribute_group pkt_stat_group = {
 204	.name = "stat",
 205	.attrs = pkt_stat_attrs,
 206};
 207
 208static ssize_t size_show(struct device *dev,
 209			 struct device_attribute *attr, char *buf)
 210{
 211	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 212	int n;
 213
 214	spin_lock(&pd->lock);
 215	n = sysfs_emit(buf, "%d\n", pd->bio_queue_size);
 216	spin_unlock(&pd->lock);
 217	return n;
 218}
 219static DEVICE_ATTR_RO(size);
 220
 221static void init_write_congestion_marks(int* lo, int* hi)
 222{
 223	if (*hi > 0) {
 224		*hi = max(*hi, 500);
 225		*hi = min(*hi, 1000000);
 226		if (*lo <= 0)
 227			*lo = *hi - 100;
 228		else {
 229			*lo = min(*lo, *hi - 100);
 230			*lo = max(*lo, 100);
 231		}
 232	} else {
 233		*hi = -1;
 234		*lo = -1;
 235	}
 236}
 237
 238static ssize_t congestion_off_show(struct device *dev,
 239				   struct device_attribute *attr, char *buf)
 
 240{
 241	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 242	int n;
 243
 244	spin_lock(&pd->lock);
 245	n = sysfs_emit(buf, "%d\n", pd->write_congestion_off);
 246	spin_unlock(&pd->lock);
 247	return n;
 248}
 
 249
 250static ssize_t congestion_off_store(struct device *dev,
 251				    struct device_attribute *attr,
 252				    const char *buf, size_t len)
 253{
 254	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 255	int val;
 256
 257	if (sscanf(buf, "%d", &val) == 1) {
 258		spin_lock(&pd->lock);
 259		pd->write_congestion_off = val;
 260		init_write_congestion_marks(&pd->write_congestion_off,
 261					&pd->write_congestion_on);
 262		spin_unlock(&pd->lock);
 263	}
 264	return len;
 265}
 266static DEVICE_ATTR_RW(congestion_off);
 267
 268static ssize_t congestion_on_show(struct device *dev,
 269				  struct device_attribute *attr, char *buf)
 270{
 271	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 272	int n;
 273
 274	spin_lock(&pd->lock);
 275	n = sysfs_emit(buf, "%d\n", pd->write_congestion_on);
 276	spin_unlock(&pd->lock);
 277	return n;
 278}
 279
 280static ssize_t congestion_on_store(struct device *dev,
 281				   struct device_attribute *attr,
 282				   const char *buf, size_t len)
 283{
 284	struct pktcdvd_device *pd = dev_get_drvdata(dev);
 285	int val;
 286
 287	if (sscanf(buf, "%d", &val) == 1) {
 288		spin_lock(&pd->lock);
 289		pd->write_congestion_on = val;
 290		init_write_congestion_marks(&pd->write_congestion_off,
 291					&pd->write_congestion_on);
 292		spin_unlock(&pd->lock);
 293	}
 294	return len;
 295}
 296static DEVICE_ATTR_RW(congestion_on);
 297
 298static struct attribute *pkt_wq_attrs[] = {
 299	&dev_attr_congestion_on.attr,
 300	&dev_attr_congestion_off.attr,
 301	&dev_attr_size.attr,
 302	NULL,
 303};
 304
 305static const struct attribute_group pkt_wq_group = {
 306	.name = "write_queue",
 307	.attrs = pkt_wq_attrs,
 308};
 309
 310static const struct attribute_group *pkt_groups[] = {
 311	&pkt_stat_group,
 312	&pkt_wq_group,
 313	NULL,
 314};
 315
 316static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 317{
 318	if (class_pktcdvd) {
 319		pd->dev = device_create_with_groups(class_pktcdvd, NULL,
 320						    MKDEV(0, 0), pd, pkt_groups,
 321						    "%s", pd->name);
 322		if (IS_ERR(pd->dev))
 323			pd->dev = NULL;
 324	}
 
 
 
 
 
 
 
 
 325}
 326
 327static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 328{
 
 
 329	if (class_pktcdvd)
 330		device_unregister(pd->dev);
 331}
 332
 333
 334/********************************************************************
 335  /sys/class/pktcdvd/
 336                     add            map block device
 337                     remove         unmap packet dev
 338                     device_map     show mappings
 339 *******************************************************************/
 340
 341static void class_pktcdvd_release(struct class *cls)
 342{
 343	kfree(cls);
 344}
 345
 346static ssize_t device_map_show(struct class *c, struct class_attribute *attr,
 347			       char *data)
 348{
 349	int n = 0;
 350	int idx;
 351	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 352	for (idx = 0; idx < MAX_WRITERS; idx++) {
 353		struct pktcdvd_device *pd = pkt_devs[idx];
 354		if (!pd)
 355			continue;
 356		n += sprintf(data+n, "%s %u:%u %u:%u\n",
 357			pd->name,
 358			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 359			MAJOR(pd->bdev->bd_dev),
 360			MINOR(pd->bdev->bd_dev));
 361	}
 362	mutex_unlock(&ctl_mutex);
 363	return n;
 364}
 365static CLASS_ATTR_RO(device_map);
 366
 367static ssize_t add_store(struct class *c, struct class_attribute *attr,
 368			 const char *buf, size_t count)
 369{
 370	unsigned int major, minor;
 371
 372	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 373		/* pkt_setup_dev() expects caller to hold reference to self */
 374		if (!try_module_get(THIS_MODULE))
 375			return -ENODEV;
 376
 377		pkt_setup_dev(MKDEV(major, minor), NULL);
 378
 379		module_put(THIS_MODULE);
 380
 381		return count;
 382	}
 383
 384	return -EINVAL;
 385}
 386static CLASS_ATTR_WO(add);
 387
 388static ssize_t remove_store(struct class *c, struct class_attribute *attr,
 389			    const char *buf, size_t count)
 390{
 391	unsigned int major, minor;
 392	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 393		pkt_remove_dev(MKDEV(major, minor));
 394		return count;
 395	}
 396	return -EINVAL;
 397}
 398static CLASS_ATTR_WO(remove);
 399
 400static struct attribute *class_pktcdvd_attrs[] = {
 401	&class_attr_add.attr,
 402	&class_attr_remove.attr,
 403	&class_attr_device_map.attr,
 404	NULL,
 405};
 406ATTRIBUTE_GROUPS(class_pktcdvd);
 407
 408static int pkt_sysfs_init(void)
 409{
 410	int ret = 0;
 411
 412	/*
 413	 * create control files in sysfs
 414	 * /sys/class/pktcdvd/...
 415	 */
 416	class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 417	if (!class_pktcdvd)
 418		return -ENOMEM;
 419	class_pktcdvd->name = DRIVER_NAME;
 420	class_pktcdvd->owner = THIS_MODULE;
 421	class_pktcdvd->class_release = class_pktcdvd_release;
 422	class_pktcdvd->class_groups = class_pktcdvd_groups;
 423	ret = class_register(class_pktcdvd);
 424	if (ret) {
 425		kfree(class_pktcdvd);
 426		class_pktcdvd = NULL;
 427		pr_err("failed to create class pktcdvd\n");
 428		return ret;
 429	}
 430	return 0;
 431}
 432
 433static void pkt_sysfs_cleanup(void)
 434{
 435	if (class_pktcdvd)
 436		class_destroy(class_pktcdvd);
 437	class_pktcdvd = NULL;
 438}
 439
 440/********************************************************************
 441  entries in debugfs
 442
 443  /sys/kernel/debug/pktcdvd[0-7]/
 444			info
 445
 446 *******************************************************************/
 447
 448static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 449{
 450	return pkt_seq_show(m, p);
 451}
 452
 453static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 454{
 455	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 456}
 457
 458static const struct file_operations debug_fops = {
 459	.open		= pkt_debugfs_fops_open,
 460	.read		= seq_read,
 461	.llseek		= seq_lseek,
 462	.release	= single_release,
 463	.owner		= THIS_MODULE,
 464};
 465
 466static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 467{
 468	if (!pkt_debugfs_root)
 469		return;
 470	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 471	if (!pd->dfs_d_root)
 472		return;
 473
 474	pd->dfs_f_info = debugfs_create_file("info", 0444,
 475					     pd->dfs_d_root, pd, &debug_fops);
 476}
 477
 478static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 479{
 480	if (!pkt_debugfs_root)
 481		return;
 482	debugfs_remove(pd->dfs_f_info);
 483	debugfs_remove(pd->dfs_d_root);
 484	pd->dfs_f_info = NULL;
 485	pd->dfs_d_root = NULL;
 486}
 487
 488static void pkt_debugfs_init(void)
 489{
 490	pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 491}
 492
 493static void pkt_debugfs_cleanup(void)
 494{
 495	debugfs_remove(pkt_debugfs_root);
 496	pkt_debugfs_root = NULL;
 497}
 498
 499/* ----------------------------------------------------------*/
 500
 501
 502static void pkt_bio_finished(struct pktcdvd_device *pd)
 503{
 504	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 505	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 506		pkt_dbg(2, pd, "queue empty\n");
 507		atomic_set(&pd->iosched.attention, 1);
 508		wake_up(&pd->wqueue);
 509	}
 510}
 511
 512/*
 513 * Allocate a packet_data struct
 514 */
 515static struct packet_data *pkt_alloc_packet_data(int frames)
 516{
 517	int i;
 518	struct packet_data *pkt;
 519
 520	pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 521	if (!pkt)
 522		goto no_pkt;
 523
 524	pkt->frames = frames;
 525	pkt->w_bio = bio_kmalloc(frames, GFP_KERNEL);
 526	if (!pkt->w_bio)
 527		goto no_bio;
 528
 529	for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 530		pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 531		if (!pkt->pages[i])
 532			goto no_page;
 533	}
 534
 535	spin_lock_init(&pkt->lock);
 536	bio_list_init(&pkt->orig_bios);
 537
 538	for (i = 0; i < frames; i++) {
 539		pkt->r_bios[i] = bio_kmalloc(1, GFP_KERNEL);
 540		if (!pkt->r_bios[i])
 541			goto no_rd_bio;
 
 
 542	}
 543
 544	return pkt;
 545
 546no_rd_bio:
 547	for (i = 0; i < frames; i++)
 548		kfree(pkt->r_bios[i]);
 
 
 
 
 549no_page:
 550	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 551		if (pkt->pages[i])
 552			__free_page(pkt->pages[i]);
 553	kfree(pkt->w_bio);
 554no_bio:
 555	kfree(pkt);
 556no_pkt:
 557	return NULL;
 558}
 559
 560/*
 561 * Free a packet_data struct
 562 */
 563static void pkt_free_packet_data(struct packet_data *pkt)
 564{
 565	int i;
 566
 567	for (i = 0; i < pkt->frames; i++)
 568		kfree(pkt->r_bios[i]);
 
 
 
 569	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 570		__free_page(pkt->pages[i]);
 571	kfree(pkt->w_bio);
 572	kfree(pkt);
 573}
 574
 575static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 576{
 577	struct packet_data *pkt, *next;
 578
 579	BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 580
 581	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 582		pkt_free_packet_data(pkt);
 583	}
 584	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 585}
 586
 587static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 588{
 589	struct packet_data *pkt;
 590
 591	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 592
 593	while (nr_packets > 0) {
 594		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 595		if (!pkt) {
 596			pkt_shrink_pktlist(pd);
 597			return 0;
 598		}
 599		pkt->id = nr_packets;
 600		pkt->pd = pd;
 601		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 602		nr_packets--;
 603	}
 604	return 1;
 605}
 606
 607static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 608{
 609	struct rb_node *n = rb_next(&node->rb_node);
 610	if (!n)
 611		return NULL;
 612	return rb_entry(n, struct pkt_rb_node, rb_node);
 613}
 614
 615static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 616{
 617	rb_erase(&node->rb_node, &pd->bio_queue);
 618	mempool_free(node, &pd->rb_pool);
 619	pd->bio_queue_size--;
 620	BUG_ON(pd->bio_queue_size < 0);
 621}
 622
 623/*
 624 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 625 */
 626static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 627{
 628	struct rb_node *n = pd->bio_queue.rb_node;
 629	struct rb_node *next;
 630	struct pkt_rb_node *tmp;
 631
 632	if (!n) {
 633		BUG_ON(pd->bio_queue_size > 0);
 634		return NULL;
 635	}
 636
 637	for (;;) {
 638		tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 639		if (s <= tmp->bio->bi_iter.bi_sector)
 640			next = n->rb_left;
 641		else
 642			next = n->rb_right;
 643		if (!next)
 644			break;
 645		n = next;
 646	}
 647
 648	if (s > tmp->bio->bi_iter.bi_sector) {
 649		tmp = pkt_rbtree_next(tmp);
 650		if (!tmp)
 651			return NULL;
 652	}
 653	BUG_ON(s > tmp->bio->bi_iter.bi_sector);
 654	return tmp;
 655}
 656
 657/*
 658 * Insert a node into the pd->bio_queue rb tree.
 659 */
 660static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 661{
 662	struct rb_node **p = &pd->bio_queue.rb_node;
 663	struct rb_node *parent = NULL;
 664	sector_t s = node->bio->bi_iter.bi_sector;
 665	struct pkt_rb_node *tmp;
 666
 667	while (*p) {
 668		parent = *p;
 669		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 670		if (s < tmp->bio->bi_iter.bi_sector)
 671			p = &(*p)->rb_left;
 672		else
 673			p = &(*p)->rb_right;
 674	}
 675	rb_link_node(&node->rb_node, parent, p);
 676	rb_insert_color(&node->rb_node, &pd->bio_queue);
 677	pd->bio_queue_size++;
 678}
 679
 680/*
 681 * Send a packet_command to the underlying block device and
 682 * wait for completion.
 683 */
 684static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 685{
 686	struct request_queue *q = bdev_get_queue(pd->bdev);
 687	struct scsi_cmnd *scmd;
 688	struct request *rq;
 689	int ret = 0;
 690
 691	rq = scsi_alloc_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 692			     REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
 693	if (IS_ERR(rq))
 694		return PTR_ERR(rq);
 695	scmd = blk_mq_rq_to_pdu(rq);
 696
 697	if (cgc->buflen) {
 698		ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
 699				      GFP_NOIO);
 700		if (ret)
 701			goto out;
 702	}
 703
 704	scmd->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 705	memcpy(scmd->cmnd, cgc->cmd, CDROM_PACKET_SIZE);
 706
 707	rq->timeout = 60*HZ;
 708	if (cgc->quiet)
 709		rq->rq_flags |= RQF_QUIET;
 710
 711	blk_execute_rq(rq, false);
 712	if (scmd->result)
 713		ret = -EIO;
 714out:
 715	blk_mq_free_request(rq);
 716	return ret;
 717}
 718
 719static const char *sense_key_string(__u8 index)
 720{
 721	static const char * const info[] = {
 722		"No sense", "Recovered error", "Not ready",
 723		"Medium error", "Hardware error", "Illegal request",
 724		"Unit attention", "Data protect", "Blank check",
 725	};
 726
 727	return index < ARRAY_SIZE(info) ? info[index] : "INVALID";
 728}
 729
 730/*
 731 * A generic sense dump / resolve mechanism should be implemented across
 732 * all ATAPI + SCSI devices.
 733 */
 734static void pkt_dump_sense(struct pktcdvd_device *pd,
 735			   struct packet_command *cgc)
 736{
 737	struct scsi_sense_hdr *sshdr = cgc->sshdr;
 738
 739	if (sshdr)
 740		pkt_err(pd, "%*ph - sense %02x.%02x.%02x (%s)\n",
 741			CDROM_PACKET_SIZE, cgc->cmd,
 742			sshdr->sense_key, sshdr->asc, sshdr->ascq,
 743			sense_key_string(sshdr->sense_key));
 744	else
 745		pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
 746}
 747
 748/*
 749 * flush the drive cache to media
 750 */
 751static int pkt_flush_cache(struct pktcdvd_device *pd)
 752{
 753	struct packet_command cgc;
 754
 755	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 756	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 757	cgc.quiet = 1;
 758
 759	/*
 760	 * the IMMED bit -- we default to not setting it, although that
 761	 * would allow a much faster close, this is safer
 762	 */
 763#if 0
 764	cgc.cmd[1] = 1 << 1;
 765#endif
 766	return pkt_generic_packet(pd, &cgc);
 767}
 768
 769/*
 770 * speed is given as the normal factor, e.g. 4 for 4x
 771 */
 772static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 773				unsigned write_speed, unsigned read_speed)
 774{
 775	struct packet_command cgc;
 776	struct scsi_sense_hdr sshdr;
 777	int ret;
 778
 779	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 780	cgc.sshdr = &sshdr;
 781	cgc.cmd[0] = GPCMD_SET_SPEED;
 782	cgc.cmd[2] = (read_speed >> 8) & 0xff;
 783	cgc.cmd[3] = read_speed & 0xff;
 784	cgc.cmd[4] = (write_speed >> 8) & 0xff;
 785	cgc.cmd[5] = write_speed & 0xff;
 786
 787	ret = pkt_generic_packet(pd, &cgc);
 788	if (ret)
 789		pkt_dump_sense(pd, &cgc);
 790
 791	return ret;
 792}
 793
 794/*
 795 * Queue a bio for processing by the low-level CD device. Must be called
 796 * from process context.
 797 */
 798static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 799{
 800	spin_lock(&pd->iosched.lock);
 801	if (bio_data_dir(bio) == READ)
 802		bio_list_add(&pd->iosched.read_queue, bio);
 803	else
 804		bio_list_add(&pd->iosched.write_queue, bio);
 805	spin_unlock(&pd->iosched.lock);
 806
 807	atomic_set(&pd->iosched.attention, 1);
 808	wake_up(&pd->wqueue);
 809}
 810
 811/*
 812 * Process the queued read/write requests. This function handles special
 813 * requirements for CDRW drives:
 814 * - A cache flush command must be inserted before a read request if the
 815 *   previous request was a write.
 816 * - Switching between reading and writing is slow, so don't do it more often
 817 *   than necessary.
 818 * - Optimize for throughput at the expense of latency. This means that streaming
 819 *   writes will never be interrupted by a read, but if the drive has to seek
 820 *   before the next write, switch to reading instead if there are any pending
 821 *   read requests.
 822 * - Set the read speed according to current usage pattern. When only reading
 823 *   from the device, it's best to use the highest possible read speed, but
 824 *   when switching often between reading and writing, it's better to have the
 825 *   same read and write speeds.
 826 */
 827static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 828{
 829
 830	if (atomic_read(&pd->iosched.attention) == 0)
 831		return;
 832	atomic_set(&pd->iosched.attention, 0);
 833
 834	for (;;) {
 835		struct bio *bio;
 836		int reads_queued, writes_queued;
 837
 838		spin_lock(&pd->iosched.lock);
 839		reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 840		writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 841		spin_unlock(&pd->iosched.lock);
 842
 843		if (!reads_queued && !writes_queued)
 844			break;
 845
 846		if (pd->iosched.writing) {
 847			int need_write_seek = 1;
 848			spin_lock(&pd->iosched.lock);
 849			bio = bio_list_peek(&pd->iosched.write_queue);
 850			spin_unlock(&pd->iosched.lock);
 851			if (bio && (bio->bi_iter.bi_sector ==
 852				    pd->iosched.last_write))
 853				need_write_seek = 0;
 854			if (need_write_seek && reads_queued) {
 855				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 856					pkt_dbg(2, pd, "write, waiting\n");
 857					break;
 858				}
 859				pkt_flush_cache(pd);
 860				pd->iosched.writing = 0;
 861			}
 862		} else {
 863			if (!reads_queued && writes_queued) {
 864				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 865					pkt_dbg(2, pd, "read, waiting\n");
 866					break;
 867				}
 868				pd->iosched.writing = 1;
 869			}
 870		}
 871
 872		spin_lock(&pd->iosched.lock);
 873		if (pd->iosched.writing)
 874			bio = bio_list_pop(&pd->iosched.write_queue);
 875		else
 876			bio = bio_list_pop(&pd->iosched.read_queue);
 877		spin_unlock(&pd->iosched.lock);
 878
 879		if (!bio)
 880			continue;
 881
 882		if (bio_data_dir(bio) == READ)
 883			pd->iosched.successive_reads +=
 884				bio->bi_iter.bi_size >> 10;
 885		else {
 886			pd->iosched.successive_reads = 0;
 887			pd->iosched.last_write = bio_end_sector(bio);
 888		}
 889		if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 890			if (pd->read_speed == pd->write_speed) {
 891				pd->read_speed = MAX_SPEED;
 892				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 893			}
 894		} else {
 895			if (pd->read_speed != pd->write_speed) {
 896				pd->read_speed = pd->write_speed;
 897				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 898			}
 899		}
 900
 901		atomic_inc(&pd->cdrw.pending_bios);
 902		submit_bio_noacct(bio);
 903	}
 904}
 905
 906/*
 907 * Special care is needed if the underlying block device has a small
 908 * max_phys_segments value.
 909 */
 910static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 911{
 912	if ((pd->settings.size << 9) / CD_FRAMESIZE
 913	    <= queue_max_segments(q)) {
 914		/*
 915		 * The cdrom device can handle one segment/frame
 916		 */
 917		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 918		return 0;
 919	} else if ((pd->settings.size << 9) / PAGE_SIZE
 920		   <= queue_max_segments(q)) {
 921		/*
 922		 * We can handle this case at the expense of some extra memory
 923		 * copies during write operations
 924		 */
 925		set_bit(PACKET_MERGE_SEGS, &pd->flags);
 926		return 0;
 927	} else {
 928		pkt_err(pd, "cdrom max_phys_segments too small\n");
 929		return -EIO;
 930	}
 931}
 932
 933static void pkt_end_io_read(struct bio *bio)
 934{
 935	struct packet_data *pkt = bio->bi_private;
 936	struct pktcdvd_device *pd = pkt->pd;
 937	BUG_ON(!pd);
 938
 939	pkt_dbg(2, pd, "bio=%p sec0=%llx sec=%llx err=%d\n",
 940		bio, (unsigned long long)pkt->sector,
 941		(unsigned long long)bio->bi_iter.bi_sector, bio->bi_status);
 942
 943	if (bio->bi_status)
 944		atomic_inc(&pkt->io_errors);
 945	bio_uninit(bio);
 946	if (atomic_dec_and_test(&pkt->io_wait)) {
 947		atomic_inc(&pkt->run_sm);
 948		wake_up(&pd->wqueue);
 949	}
 950	pkt_bio_finished(pd);
 951}
 952
 953static void pkt_end_io_packet_write(struct bio *bio)
 954{
 955	struct packet_data *pkt = bio->bi_private;
 956	struct pktcdvd_device *pd = pkt->pd;
 957	BUG_ON(!pd);
 958
 959	pkt_dbg(2, pd, "id=%d, err=%d\n", pkt->id, bio->bi_status);
 960
 961	pd->stats.pkt_ended++;
 962
 963	bio_uninit(bio);
 964	pkt_bio_finished(pd);
 965	atomic_dec(&pkt->io_wait);
 966	atomic_inc(&pkt->run_sm);
 967	wake_up(&pd->wqueue);
 968}
 969
 970/*
 971 * Schedule reads for the holes in a packet
 972 */
 973static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
 974{
 975	int frames_read = 0;
 976	struct bio *bio;
 977	int f;
 978	char written[PACKET_MAX_SIZE];
 979
 980	BUG_ON(bio_list_empty(&pkt->orig_bios));
 981
 982	atomic_set(&pkt->io_wait, 0);
 983	atomic_set(&pkt->io_errors, 0);
 984
 985	/*
 986	 * Figure out which frames we need to read before we can write.
 987	 */
 988	memset(written, 0, sizeof(written));
 989	spin_lock(&pkt->lock);
 990	bio_list_for_each(bio, &pkt->orig_bios) {
 991		int first_frame = (bio->bi_iter.bi_sector - pkt->sector) /
 992			(CD_FRAMESIZE >> 9);
 993		int num_frames = bio->bi_iter.bi_size / CD_FRAMESIZE;
 994		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
 995		BUG_ON(first_frame < 0);
 996		BUG_ON(first_frame + num_frames > pkt->frames);
 997		for (f = first_frame; f < first_frame + num_frames; f++)
 998			written[f] = 1;
 999	}
1000	spin_unlock(&pkt->lock);
1001
1002	if (pkt->cache_valid) {
1003		pkt_dbg(2, pd, "zone %llx cached\n",
1004			(unsigned long long)pkt->sector);
1005		goto out_account;
1006	}
1007
1008	/*
1009	 * Schedule reads for missing parts of the packet.
1010	 */
1011	for (f = 0; f < pkt->frames; f++) {
1012		int p, offset;
1013
1014		if (written[f])
1015			continue;
1016
1017		bio = pkt->r_bios[f];
1018		bio_init(bio, pd->bdev, bio->bi_inline_vecs, 1, REQ_OP_READ);
1019		bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 
1020		bio->bi_end_io = pkt_end_io_read;
1021		bio->bi_private = pkt;
1022
1023		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1024		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1025		pkt_dbg(2, pd, "Adding frame %d, page:%p offs:%d\n",
1026			f, pkt->pages[p], offset);
1027		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1028			BUG();
1029
1030		atomic_inc(&pkt->io_wait);
 
1031		pkt_queue_bio(pd, bio);
1032		frames_read++;
1033	}
1034
1035out_account:
1036	pkt_dbg(2, pd, "need %d frames for zone %llx\n",
1037		frames_read, (unsigned long long)pkt->sector);
1038	pd->stats.pkt_started++;
1039	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1040}
1041
1042/*
1043 * Find a packet matching zone, or the least recently used packet if
1044 * there is no match.
1045 */
1046static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1047{
1048	struct packet_data *pkt;
1049
1050	list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1051		if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1052			list_del_init(&pkt->list);
1053			if (pkt->sector != zone)
1054				pkt->cache_valid = 0;
1055			return pkt;
1056		}
1057	}
1058	BUG();
1059	return NULL;
1060}
1061
1062static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1063{
1064	if (pkt->cache_valid) {
1065		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1066	} else {
1067		list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1068	}
1069}
1070
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1071static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1072{
1073#if PACKET_DEBUG > 1
1074	static const char *state_name[] = {
1075		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1076	};
1077	enum packet_data_state old_state = pkt->state;
1078	pkt_dbg(2, pd, "pkt %2d : s=%6llx %s -> %s\n",
1079		pkt->id, (unsigned long long)pkt->sector,
1080		state_name[old_state], state_name[state]);
1081#endif
1082	pkt->state = state;
1083}
1084
1085/*
1086 * Scan the work queue to see if we can start a new packet.
1087 * returns non-zero if any work was done.
1088 */
1089static int pkt_handle_queue(struct pktcdvd_device *pd)
1090{
1091	struct packet_data *pkt, *p;
1092	struct bio *bio = NULL;
1093	sector_t zone = 0; /* Suppress gcc warning */
1094	struct pkt_rb_node *node, *first_node;
1095	struct rb_node *n;
 
1096
1097	atomic_set(&pd->scan_queue, 0);
1098
1099	if (list_empty(&pd->cdrw.pkt_free_list)) {
1100		pkt_dbg(2, pd, "no pkt\n");
1101		return 0;
1102	}
1103
1104	/*
1105	 * Try to find a zone we are not already working on.
1106	 */
1107	spin_lock(&pd->lock);
1108	first_node = pkt_rbtree_find(pd, pd->current_sector);
1109	if (!first_node) {
1110		n = rb_first(&pd->bio_queue);
1111		if (n)
1112			first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1113	}
1114	node = first_node;
1115	while (node) {
1116		bio = node->bio;
1117		zone = get_zone(bio->bi_iter.bi_sector, pd);
1118		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1119			if (p->sector == zone) {
1120				bio = NULL;
1121				goto try_next_bio;
1122			}
1123		}
1124		break;
1125try_next_bio:
1126		node = pkt_rbtree_next(node);
1127		if (!node) {
1128			n = rb_first(&pd->bio_queue);
1129			if (n)
1130				node = rb_entry(n, struct pkt_rb_node, rb_node);
1131		}
1132		if (node == first_node)
1133			node = NULL;
1134	}
1135	spin_unlock(&pd->lock);
1136	if (!bio) {
1137		pkt_dbg(2, pd, "no bio\n");
1138		return 0;
1139	}
1140
1141	pkt = pkt_get_packet_data(pd, zone);
1142
1143	pd->current_sector = zone + pd->settings.size;
1144	pkt->sector = zone;
1145	BUG_ON(pkt->frames != pd->settings.size >> 2);
1146	pkt->write_size = 0;
1147
1148	/*
1149	 * Scan work queue for bios in the same zone and link them
1150	 * to this packet.
1151	 */
1152	spin_lock(&pd->lock);
1153	pkt_dbg(2, pd, "looking for zone %llx\n", (unsigned long long)zone);
1154	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1155		bio = node->bio;
1156		pkt_dbg(2, pd, "found zone=%llx\n", (unsigned long long)
1157			get_zone(bio->bi_iter.bi_sector, pd));
1158		if (get_zone(bio->bi_iter.bi_sector, pd) != zone)
1159			break;
1160		pkt_rbtree_erase(pd, node);
1161		spin_lock(&pkt->lock);
1162		bio_list_add(&pkt->orig_bios, bio);
1163		pkt->write_size += bio->bi_iter.bi_size / CD_FRAMESIZE;
1164		spin_unlock(&pkt->lock);
1165	}
1166	/* check write congestion marks, and if bio_queue_size is
1167	 * below, wake up any waiters
1168	 */
1169	if (pd->congested &&
1170	    pd->bio_queue_size <= pd->write_congestion_off) {
1171		pd->congested = false;
1172		wake_up_var(&pd->congested);
 
1173	}
1174	spin_unlock(&pd->lock);
1175
1176	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1177	pkt_set_state(pkt, PACKET_WAITING_STATE);
1178	atomic_set(&pkt->run_sm, 1);
1179
1180	spin_lock(&pd->cdrw.active_list_lock);
1181	list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1182	spin_unlock(&pd->cdrw.active_list_lock);
1183
1184	return 1;
1185}
1186
1187/**
1188 * bio_list_copy_data - copy contents of data buffers from one chain of bios to
1189 * another
1190 * @src: source bio list
1191 * @dst: destination bio list
1192 *
1193 * Stops when it reaches the end of either the @src list or @dst list - that is,
1194 * copies min(src->bi_size, dst->bi_size) bytes (or the equivalent for lists of
1195 * bios).
1196 */
1197static void bio_list_copy_data(struct bio *dst, struct bio *src)
1198{
1199	struct bvec_iter src_iter = src->bi_iter;
1200	struct bvec_iter dst_iter = dst->bi_iter;
1201
1202	while (1) {
1203		if (!src_iter.bi_size) {
1204			src = src->bi_next;
1205			if (!src)
1206				break;
1207
1208			src_iter = src->bi_iter;
1209		}
1210
1211		if (!dst_iter.bi_size) {
1212			dst = dst->bi_next;
1213			if (!dst)
1214				break;
1215
1216			dst_iter = dst->bi_iter;
1217		}
1218
1219		bio_copy_data_iter(dst, &dst_iter, src, &src_iter);
1220	}
1221}
1222
1223/*
1224 * Assemble a bio to write one packet and queue the bio for processing
1225 * by the underlying block device.
1226 */
1227static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1228{
1229	int f;
1230
1231	bio_init(pkt->w_bio, pd->bdev, pkt->w_bio->bi_inline_vecs, pkt->frames,
1232		 REQ_OP_WRITE);
1233	pkt->w_bio->bi_iter.bi_sector = pkt->sector;
 
1234	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1235	pkt->w_bio->bi_private = pkt;
1236
1237	/* XXX: locking? */
1238	for (f = 0; f < pkt->frames; f++) {
1239		struct page *page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1240		unsigned offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1241
1242		if (!bio_add_page(pkt->w_bio, page, CD_FRAMESIZE, offset))
1243			BUG();
1244	}
1245	pkt_dbg(2, pd, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
1246
1247	/*
1248	 * Fill-in bvec with data from orig_bios.
1249	 */
1250	spin_lock(&pkt->lock);
1251	bio_list_copy_data(pkt->w_bio, pkt->orig_bios.head);
1252
1253	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1254	spin_unlock(&pkt->lock);
1255
1256	pkt_dbg(2, pd, "Writing %d frames for zone %llx\n",
1257		pkt->write_size, (unsigned long long)pkt->sector);
1258
1259	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames))
1260		pkt->cache_valid = 1;
1261	else
1262		pkt->cache_valid = 0;
1263
1264	/* Start the write request */
1265	atomic_set(&pkt->io_wait, 1);
 
1266	pkt_queue_bio(pd, pkt->w_bio);
1267}
1268
1269static void pkt_finish_packet(struct packet_data *pkt, blk_status_t status)
1270{
1271	struct bio *bio;
1272
1273	if (status)
1274		pkt->cache_valid = 0;
1275
1276	/* Finish all bios corresponding to this packet */
1277	while ((bio = bio_list_pop(&pkt->orig_bios))) {
1278		bio->bi_status = status;
1279		bio_endio(bio);
1280	}
1281}
1282
1283static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1284{
1285	pkt_dbg(2, pd, "pkt %d\n", pkt->id);
1286
1287	for (;;) {
1288		switch (pkt->state) {
1289		case PACKET_WAITING_STATE:
1290			if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1291				return;
1292
1293			pkt->sleep_time = 0;
1294			pkt_gather_data(pd, pkt);
1295			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1296			break;
1297
1298		case PACKET_READ_WAIT_STATE:
1299			if (atomic_read(&pkt->io_wait) > 0)
1300				return;
1301
1302			if (atomic_read(&pkt->io_errors) > 0) {
1303				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1304			} else {
1305				pkt_start_write(pd, pkt);
1306			}
1307			break;
1308
1309		case PACKET_WRITE_WAIT_STATE:
1310			if (atomic_read(&pkt->io_wait) > 0)
1311				return;
1312
1313			if (!pkt->w_bio->bi_status) {
1314				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1315			} else {
1316				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1317			}
1318			break;
1319
1320		case PACKET_RECOVERY_STATE:
1321			pkt_dbg(2, pd, "No recovery possible\n");
1322			pkt_set_state(pkt, PACKET_FINISHED_STATE);
 
 
 
 
1323			break;
1324
1325		case PACKET_FINISHED_STATE:
1326			pkt_finish_packet(pkt, pkt->w_bio->bi_status);
1327			return;
1328
1329		default:
1330			BUG();
1331			break;
1332		}
1333	}
1334}
1335
1336static void pkt_handle_packets(struct pktcdvd_device *pd)
1337{
1338	struct packet_data *pkt, *next;
1339
1340	/*
1341	 * Run state machine for active packets
1342	 */
1343	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1344		if (atomic_read(&pkt->run_sm) > 0) {
1345			atomic_set(&pkt->run_sm, 0);
1346			pkt_run_state_machine(pd, pkt);
1347		}
1348	}
1349
1350	/*
1351	 * Move no longer active packets to the free list
1352	 */
1353	spin_lock(&pd->cdrw.active_list_lock);
1354	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1355		if (pkt->state == PACKET_FINISHED_STATE) {
1356			list_del(&pkt->list);
1357			pkt_put_packet_data(pd, pkt);
1358			pkt_set_state(pkt, PACKET_IDLE_STATE);
1359			atomic_set(&pd->scan_queue, 1);
1360		}
1361	}
1362	spin_unlock(&pd->cdrw.active_list_lock);
1363}
1364
1365static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1366{
1367	struct packet_data *pkt;
1368	int i;
1369
1370	for (i = 0; i < PACKET_NUM_STATES; i++)
1371		states[i] = 0;
1372
1373	spin_lock(&pd->cdrw.active_list_lock);
1374	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1375		states[pkt->state]++;
1376	}
1377	spin_unlock(&pd->cdrw.active_list_lock);
1378}
1379
1380/*
1381 * kcdrwd is woken up when writes have been queued for one of our
1382 * registered devices
1383 */
1384static int kcdrwd(void *foobar)
1385{
1386	struct pktcdvd_device *pd = foobar;
1387	struct packet_data *pkt;
1388	long min_sleep_time, residue;
1389
1390	set_user_nice(current, MIN_NICE);
1391	set_freezable();
1392
1393	for (;;) {
1394		DECLARE_WAITQUEUE(wait, current);
1395
1396		/*
1397		 * Wait until there is something to do
1398		 */
1399		add_wait_queue(&pd->wqueue, &wait);
1400		for (;;) {
1401			set_current_state(TASK_INTERRUPTIBLE);
1402
1403			/* Check if we need to run pkt_handle_queue */
1404			if (atomic_read(&pd->scan_queue) > 0)
1405				goto work_to_do;
1406
1407			/* Check if we need to run the state machine for some packet */
1408			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1409				if (atomic_read(&pkt->run_sm) > 0)
1410					goto work_to_do;
1411			}
1412
1413			/* Check if we need to process the iosched queues */
1414			if (atomic_read(&pd->iosched.attention) != 0)
1415				goto work_to_do;
1416
1417			/* Otherwise, go to sleep */
1418			if (PACKET_DEBUG > 1) {
1419				int states[PACKET_NUM_STATES];
1420				pkt_count_states(pd, states);
1421				pkt_dbg(2, pd, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1422					states[0], states[1], states[2],
1423					states[3], states[4], states[5]);
1424			}
1425
1426			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1427			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1428				if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1429					min_sleep_time = pkt->sleep_time;
1430			}
1431
1432			pkt_dbg(2, pd, "sleeping\n");
1433			residue = schedule_timeout(min_sleep_time);
1434			pkt_dbg(2, pd, "wake up\n");
1435
1436			/* make swsusp happy with our thread */
1437			try_to_freeze();
1438
1439			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1440				if (!pkt->sleep_time)
1441					continue;
1442				pkt->sleep_time -= min_sleep_time - residue;
1443				if (pkt->sleep_time <= 0) {
1444					pkt->sleep_time = 0;
1445					atomic_inc(&pkt->run_sm);
1446				}
1447			}
1448
1449			if (kthread_should_stop())
1450				break;
1451		}
1452work_to_do:
1453		set_current_state(TASK_RUNNING);
1454		remove_wait_queue(&pd->wqueue, &wait);
1455
1456		if (kthread_should_stop())
1457			break;
1458
1459		/*
1460		 * if pkt_handle_queue returns true, we can queue
1461		 * another request.
1462		 */
1463		while (pkt_handle_queue(pd))
1464			;
1465
1466		/*
1467		 * Handle packet state machine
1468		 */
1469		pkt_handle_packets(pd);
1470
1471		/*
1472		 * Handle iosched queues
1473		 */
1474		pkt_iosched_process_queue(pd);
1475	}
1476
1477	return 0;
1478}
1479
1480static void pkt_print_settings(struct pktcdvd_device *pd)
1481{
1482	pkt_info(pd, "%s packets, %u blocks, Mode-%c disc\n",
1483		 pd->settings.fp ? "Fixed" : "Variable",
1484		 pd->settings.size >> 2,
1485		 pd->settings.block_mode == 8 ? '1' : '2');
1486}
1487
1488static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1489{
1490	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1491
1492	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1493	cgc->cmd[2] = page_code | (page_control << 6);
1494	cgc->cmd[7] = cgc->buflen >> 8;
1495	cgc->cmd[8] = cgc->buflen & 0xff;
1496	cgc->data_direction = CGC_DATA_READ;
1497	return pkt_generic_packet(pd, cgc);
1498}
1499
1500static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1501{
1502	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1503	memset(cgc->buffer, 0, 2);
1504	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1505	cgc->cmd[1] = 0x10;		/* PF */
1506	cgc->cmd[7] = cgc->buflen >> 8;
1507	cgc->cmd[8] = cgc->buflen & 0xff;
1508	cgc->data_direction = CGC_DATA_WRITE;
1509	return pkt_generic_packet(pd, cgc);
1510}
1511
1512static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1513{
1514	struct packet_command cgc;
1515	int ret;
1516
1517	/* set up command and get the disc info */
1518	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1519	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1520	cgc.cmd[8] = cgc.buflen = 2;
1521	cgc.quiet = 1;
1522
1523	ret = pkt_generic_packet(pd, &cgc);
1524	if (ret)
1525		return ret;
1526
1527	/* not all drives have the same disc_info length, so requeue
1528	 * packet with the length the drive tells us it can supply
1529	 */
1530	cgc.buflen = be16_to_cpu(di->disc_information_length) +
1531		     sizeof(di->disc_information_length);
1532
1533	if (cgc.buflen > sizeof(disc_information))
1534		cgc.buflen = sizeof(disc_information);
1535
1536	cgc.cmd[8] = cgc.buflen;
1537	return pkt_generic_packet(pd, &cgc);
1538}
1539
1540static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1541{
1542	struct packet_command cgc;
1543	int ret;
1544
1545	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1546	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1547	cgc.cmd[1] = type & 3;
1548	cgc.cmd[4] = (track & 0xff00) >> 8;
1549	cgc.cmd[5] = track & 0xff;
1550	cgc.cmd[8] = 8;
1551	cgc.quiet = 1;
1552
1553	ret = pkt_generic_packet(pd, &cgc);
1554	if (ret)
1555		return ret;
1556
1557	cgc.buflen = be16_to_cpu(ti->track_information_length) +
1558		     sizeof(ti->track_information_length);
1559
1560	if (cgc.buflen > sizeof(track_information))
1561		cgc.buflen = sizeof(track_information);
1562
1563	cgc.cmd[8] = cgc.buflen;
1564	return pkt_generic_packet(pd, &cgc);
1565}
1566
1567static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1568						long *last_written)
1569{
1570	disc_information di;
1571	track_information ti;
1572	__u32 last_track;
1573	int ret;
1574
1575	ret = pkt_get_disc_info(pd, &di);
1576	if (ret)
1577		return ret;
1578
1579	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1580	ret = pkt_get_track_info(pd, last_track, 1, &ti);
1581	if (ret)
1582		return ret;
1583
1584	/* if this track is blank, try the previous. */
1585	if (ti.blank) {
1586		last_track--;
1587		ret = pkt_get_track_info(pd, last_track, 1, &ti);
1588		if (ret)
1589			return ret;
1590	}
1591
1592	/* if last recorded field is valid, return it. */
1593	if (ti.lra_v) {
1594		*last_written = be32_to_cpu(ti.last_rec_address);
1595	} else {
1596		/* make it up instead */
1597		*last_written = be32_to_cpu(ti.track_start) +
1598				be32_to_cpu(ti.track_size);
1599		if (ti.free_blocks)
1600			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1601	}
1602	return 0;
1603}
1604
1605/*
1606 * write mode select package based on pd->settings
1607 */
1608static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1609{
1610	struct packet_command cgc;
1611	struct scsi_sense_hdr sshdr;
1612	write_param_page *wp;
1613	char buffer[128];
1614	int ret, size;
1615
1616	/* doesn't apply to DVD+RW or DVD-RAM */
1617	if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1618		return 0;
1619
1620	memset(buffer, 0, sizeof(buffer));
1621	init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1622	cgc.sshdr = &sshdr;
1623	ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0);
1624	if (ret) {
1625		pkt_dump_sense(pd, &cgc);
1626		return ret;
1627	}
1628
1629	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1630	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1631	if (size > sizeof(buffer))
1632		size = sizeof(buffer);
1633
1634	/*
1635	 * now get it all
1636	 */
1637	init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1638	cgc.sshdr = &sshdr;
1639	ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0);
1640	if (ret) {
1641		pkt_dump_sense(pd, &cgc);
1642		return ret;
1643	}
1644
1645	/*
1646	 * write page is offset header + block descriptor length
1647	 */
1648	wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1649
1650	wp->fp = pd->settings.fp;
1651	wp->track_mode = pd->settings.track_mode;
1652	wp->write_type = pd->settings.write_type;
1653	wp->data_block_type = pd->settings.block_mode;
1654
1655	wp->multi_session = 0;
1656
1657#ifdef PACKET_USE_LS
1658	wp->link_size = 7;
1659	wp->ls_v = 1;
1660#endif
1661
1662	if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1663		wp->session_format = 0;
1664		wp->subhdr2 = 0x20;
1665	} else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1666		wp->session_format = 0x20;
1667		wp->subhdr2 = 8;
1668#if 0
1669		wp->mcn[0] = 0x80;
1670		memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1671#endif
1672	} else {
1673		/*
1674		 * paranoia
1675		 */
1676		pkt_err(pd, "write mode wrong %d\n", wp->data_block_type);
1677		return 1;
1678	}
1679	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1680
1681	cgc.buflen = cgc.cmd[8] = size;
1682	ret = pkt_mode_select(pd, &cgc);
1683	if (ret) {
1684		pkt_dump_sense(pd, &cgc);
1685		return ret;
1686	}
1687
1688	pkt_print_settings(pd);
1689	return 0;
1690}
1691
1692/*
1693 * 1 -- we can write to this track, 0 -- we can't
1694 */
1695static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1696{
1697	switch (pd->mmc3_profile) {
1698		case 0x1a: /* DVD+RW */
1699		case 0x12: /* DVD-RAM */
1700			/* The track is always writable on DVD+RW/DVD-RAM */
1701			return 1;
1702		default:
1703			break;
1704	}
1705
1706	if (!ti->packet || !ti->fp)
1707		return 0;
1708
1709	/*
1710	 * "good" settings as per Mt Fuji.
1711	 */
1712	if (ti->rt == 0 && ti->blank == 0)
1713		return 1;
1714
1715	if (ti->rt == 0 && ti->blank == 1)
1716		return 1;
1717
1718	if (ti->rt == 1 && ti->blank == 0)
1719		return 1;
1720
1721	pkt_err(pd, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1722	return 0;
1723}
1724
1725/*
1726 * 1 -- we can write to this disc, 0 -- we can't
1727 */
1728static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1729{
1730	switch (pd->mmc3_profile) {
1731		case 0x0a: /* CD-RW */
1732		case 0xffff: /* MMC3 not supported */
1733			break;
1734		case 0x1a: /* DVD+RW */
1735		case 0x13: /* DVD-RW */
1736		case 0x12: /* DVD-RAM */
1737			return 1;
1738		default:
1739			pkt_dbg(2, pd, "Wrong disc profile (%x)\n",
1740				pd->mmc3_profile);
1741			return 0;
1742	}
1743
1744	/*
1745	 * for disc type 0xff we should probably reserve a new track.
1746	 * but i'm not sure, should we leave this to user apps? probably.
1747	 */
1748	if (di->disc_type == 0xff) {
1749		pkt_notice(pd, "unknown disc - no track?\n");
1750		return 0;
1751	}
1752
1753	if (di->disc_type != 0x20 && di->disc_type != 0) {
1754		pkt_err(pd, "wrong disc type (%x)\n", di->disc_type);
1755		return 0;
1756	}
1757
1758	if (di->erasable == 0) {
1759		pkt_notice(pd, "disc not erasable\n");
1760		return 0;
1761	}
1762
1763	if (di->border_status == PACKET_SESSION_RESERVED) {
1764		pkt_err(pd, "can't write to last track (reserved)\n");
1765		return 0;
1766	}
1767
1768	return 1;
1769}
1770
1771static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1772{
1773	struct packet_command cgc;
1774	unsigned char buf[12];
1775	disc_information di;
1776	track_information ti;
1777	int ret, track;
1778
1779	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1780	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1781	cgc.cmd[8] = 8;
1782	ret = pkt_generic_packet(pd, &cgc);
1783	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1784
1785	memset(&di, 0, sizeof(disc_information));
1786	memset(&ti, 0, sizeof(track_information));
1787
1788	ret = pkt_get_disc_info(pd, &di);
1789	if (ret) {
1790		pkt_err(pd, "failed get_disc\n");
1791		return ret;
1792	}
1793
1794	if (!pkt_writable_disc(pd, &di))
1795		return -EROFS;
1796
1797	pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1798
1799	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1800	ret = pkt_get_track_info(pd, track, 1, &ti);
1801	if (ret) {
1802		pkt_err(pd, "failed get_track\n");
1803		return ret;
1804	}
1805
1806	if (!pkt_writable_track(pd, &ti)) {
1807		pkt_err(pd, "can't write to this track\n");
1808		return -EROFS;
1809	}
1810
1811	/*
1812	 * we keep packet size in 512 byte units, makes it easier to
1813	 * deal with request calculations.
1814	 */
1815	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1816	if (pd->settings.size == 0) {
1817		pkt_notice(pd, "detected zero packet size!\n");
1818		return -ENXIO;
1819	}
1820	if (pd->settings.size > PACKET_MAX_SECTORS) {
1821		pkt_err(pd, "packet size is too big\n");
1822		return -EROFS;
1823	}
1824	pd->settings.fp = ti.fp;
1825	pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1826
1827	if (ti.nwa_v) {
1828		pd->nwa = be32_to_cpu(ti.next_writable);
1829		set_bit(PACKET_NWA_VALID, &pd->flags);
1830	}
1831
1832	/*
1833	 * in theory we could use lra on -RW media as well and just zero
1834	 * blocks that haven't been written yet, but in practice that
1835	 * is just a no-go. we'll use that for -R, naturally.
1836	 */
1837	if (ti.lra_v) {
1838		pd->lra = be32_to_cpu(ti.last_rec_address);
1839		set_bit(PACKET_LRA_VALID, &pd->flags);
1840	} else {
1841		pd->lra = 0xffffffff;
1842		set_bit(PACKET_LRA_VALID, &pd->flags);
1843	}
1844
1845	/*
1846	 * fine for now
1847	 */
1848	pd->settings.link_loss = 7;
1849	pd->settings.write_type = 0;	/* packet */
1850	pd->settings.track_mode = ti.track_mode;
1851
1852	/*
1853	 * mode1 or mode2 disc
1854	 */
1855	switch (ti.data_mode) {
1856		case PACKET_MODE1:
1857			pd->settings.block_mode = PACKET_BLOCK_MODE1;
1858			break;
1859		case PACKET_MODE2:
1860			pd->settings.block_mode = PACKET_BLOCK_MODE2;
1861			break;
1862		default:
1863			pkt_err(pd, "unknown data mode\n");
1864			return -EROFS;
1865	}
1866	return 0;
1867}
1868
1869/*
1870 * enable/disable write caching on drive
1871 */
1872static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
1873						int set)
1874{
1875	struct packet_command cgc;
1876	struct scsi_sense_hdr sshdr;
1877	unsigned char buf[64];
1878	int ret;
1879
1880	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1881	cgc.sshdr = &sshdr;
1882	cgc.buflen = pd->mode_offset + 12;
1883
1884	/*
1885	 * caching mode page might not be there, so quiet this command
1886	 */
1887	cgc.quiet = 1;
1888
1889	ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0);
1890	if (ret)
1891		return ret;
1892
1893	buf[pd->mode_offset + 10] |= (!!set << 2);
1894
1895	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1896	ret = pkt_mode_select(pd, &cgc);
1897	if (ret) {
1898		pkt_err(pd, "write caching control failed\n");
1899		pkt_dump_sense(pd, &cgc);
1900	} else if (!ret && set)
1901		pkt_notice(pd, "enabled write caching\n");
1902	return ret;
1903}
1904
1905static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1906{
1907	struct packet_command cgc;
1908
1909	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1910	cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1911	cgc.cmd[4] = lockflag ? 1 : 0;
1912	return pkt_generic_packet(pd, &cgc);
1913}
1914
1915/*
1916 * Returns drive maximum write speed
1917 */
1918static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1919						unsigned *write_speed)
1920{
1921	struct packet_command cgc;
1922	struct scsi_sense_hdr sshdr;
1923	unsigned char buf[256+18];
1924	unsigned char *cap_buf;
1925	int ret, offset;
1926
1927	cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1928	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1929	cgc.sshdr = &sshdr;
1930
1931	ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1932	if (ret) {
1933		cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1934			     sizeof(struct mode_page_header);
1935		ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1936		if (ret) {
1937			pkt_dump_sense(pd, &cgc);
1938			return ret;
1939		}
1940	}
1941
1942	offset = 20;			    /* Obsoleted field, used by older drives */
1943	if (cap_buf[1] >= 28)
1944		offset = 28;		    /* Current write speed selected */
1945	if (cap_buf[1] >= 30) {
1946		/* If the drive reports at least one "Logical Unit Write
1947		 * Speed Performance Descriptor Block", use the information
1948		 * in the first block. (contains the highest speed)
1949		 */
1950		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
1951		if (num_spdb > 0)
1952			offset = 34;
1953	}
1954
1955	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
1956	return 0;
1957}
1958
1959/* These tables from cdrecord - I don't have orange book */
1960/* standard speed CD-RW (1-4x) */
1961static char clv_to_speed[16] = {
1962	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1963	   0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1964};
1965/* high speed CD-RW (-10x) */
1966static char hs_clv_to_speed[16] = {
1967	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1968	   0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
1969};
1970/* ultra high speed CD-RW */
1971static char us_clv_to_speed[16] = {
1972	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
1973	   0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
1974};
1975
1976/*
1977 * reads the maximum media speed from ATIP
1978 */
1979static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
1980						unsigned *speed)
1981{
1982	struct packet_command cgc;
1983	struct scsi_sense_hdr sshdr;
1984	unsigned char buf[64];
1985	unsigned int size, st, sp;
1986	int ret;
1987
1988	init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
1989	cgc.sshdr = &sshdr;
1990	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
1991	cgc.cmd[1] = 2;
1992	cgc.cmd[2] = 4; /* READ ATIP */
1993	cgc.cmd[8] = 2;
1994	ret = pkt_generic_packet(pd, &cgc);
1995	if (ret) {
1996		pkt_dump_sense(pd, &cgc);
1997		return ret;
1998	}
1999	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2000	if (size > sizeof(buf))
2001		size = sizeof(buf);
2002
2003	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2004	cgc.sshdr = &sshdr;
2005	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2006	cgc.cmd[1] = 2;
2007	cgc.cmd[2] = 4;
2008	cgc.cmd[8] = size;
2009	ret = pkt_generic_packet(pd, &cgc);
2010	if (ret) {
2011		pkt_dump_sense(pd, &cgc);
2012		return ret;
2013	}
2014
2015	if (!(buf[6] & 0x40)) {
2016		pkt_notice(pd, "disc type is not CD-RW\n");
2017		return 1;
2018	}
2019	if (!(buf[6] & 0x4)) {
2020		pkt_notice(pd, "A1 values on media are not valid, maybe not CDRW?\n");
2021		return 1;
2022	}
2023
2024	st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2025
2026	sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2027
2028	/* Info from cdrecord */
2029	switch (st) {
2030		case 0: /* standard speed */
2031			*speed = clv_to_speed[sp];
2032			break;
2033		case 1: /* high speed */
2034			*speed = hs_clv_to_speed[sp];
2035			break;
2036		case 2: /* ultra high speed */
2037			*speed = us_clv_to_speed[sp];
2038			break;
2039		default:
2040			pkt_notice(pd, "unknown disc sub-type %d\n", st);
2041			return 1;
2042	}
2043	if (*speed) {
2044		pkt_info(pd, "maximum media speed: %d\n", *speed);
2045		return 0;
2046	} else {
2047		pkt_notice(pd, "unknown speed %d for sub-type %d\n", sp, st);
2048		return 1;
2049	}
2050}
2051
2052static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2053{
2054	struct packet_command cgc;
2055	struct scsi_sense_hdr sshdr;
2056	int ret;
2057
2058	pkt_dbg(2, pd, "Performing OPC\n");
2059
2060	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2061	cgc.sshdr = &sshdr;
2062	cgc.timeout = 60*HZ;
2063	cgc.cmd[0] = GPCMD_SEND_OPC;
2064	cgc.cmd[1] = 1;
2065	ret = pkt_generic_packet(pd, &cgc);
2066	if (ret)
2067		pkt_dump_sense(pd, &cgc);
2068	return ret;
2069}
2070
2071static int pkt_open_write(struct pktcdvd_device *pd)
2072{
2073	int ret;
2074	unsigned int write_speed, media_write_speed, read_speed;
2075
2076	ret = pkt_probe_settings(pd);
2077	if (ret) {
2078		pkt_dbg(2, pd, "failed probe\n");
2079		return ret;
2080	}
2081
2082	ret = pkt_set_write_settings(pd);
2083	if (ret) {
2084		pkt_dbg(1, pd, "failed saving write settings\n");
2085		return -EIO;
2086	}
2087
2088	pkt_write_caching(pd, USE_WCACHING);
2089
2090	ret = pkt_get_max_speed(pd, &write_speed);
2091	if (ret)
2092		write_speed = 16 * 177;
2093	switch (pd->mmc3_profile) {
2094		case 0x13: /* DVD-RW */
2095		case 0x1a: /* DVD+RW */
2096		case 0x12: /* DVD-RAM */
2097			pkt_dbg(1, pd, "write speed %ukB/s\n", write_speed);
2098			break;
2099		default:
2100			ret = pkt_media_speed(pd, &media_write_speed);
2101			if (ret)
2102				media_write_speed = 16;
2103			write_speed = min(write_speed, media_write_speed * 177);
2104			pkt_dbg(1, pd, "write speed %ux\n", write_speed / 176);
2105			break;
2106	}
2107	read_speed = write_speed;
2108
2109	ret = pkt_set_speed(pd, write_speed, read_speed);
2110	if (ret) {
2111		pkt_dbg(1, pd, "couldn't set write speed\n");
2112		return -EIO;
2113	}
2114	pd->write_speed = write_speed;
2115	pd->read_speed = read_speed;
2116
2117	ret = pkt_perform_opc(pd);
2118	if (ret) {
2119		pkt_dbg(1, pd, "Optimum Power Calibration failed\n");
2120	}
2121
2122	return 0;
2123}
2124
2125/*
2126 * called at open time.
2127 */
2128static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2129{
2130	int ret;
2131	long lba;
2132	struct request_queue *q;
2133	struct block_device *bdev;
2134
2135	/*
2136	 * We need to re-open the cdrom device without O_NONBLOCK to be able
2137	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2138	 * so open should not fail.
2139	 */
2140	bdev = blkdev_get_by_dev(pd->bdev->bd_dev, FMODE_READ | FMODE_EXCL, pd);
2141	if (IS_ERR(bdev)) {
2142		ret = PTR_ERR(bdev);
2143		goto out;
2144	}
2145
2146	ret = pkt_get_last_written(pd, &lba);
2147	if (ret) {
2148		pkt_err(pd, "pkt_get_last_written failed\n");
2149		goto out_putdev;
2150	}
2151
2152	set_capacity(pd->disk, lba << 2);
2153	set_capacity_and_notify(pd->bdev->bd_disk, lba << 2);
 
2154
2155	q = bdev_get_queue(pd->bdev);
2156	if (write) {
2157		ret = pkt_open_write(pd);
2158		if (ret)
2159			goto out_putdev;
2160		/*
2161		 * Some CDRW drives can not handle writes larger than one packet,
2162		 * even if the size is a multiple of the packet size.
2163		 */
2164		blk_queue_max_hw_sectors(q, pd->settings.size);
2165		set_bit(PACKET_WRITABLE, &pd->flags);
2166	} else {
2167		pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2168		clear_bit(PACKET_WRITABLE, &pd->flags);
2169	}
2170
2171	ret = pkt_set_segment_merging(pd, q);
2172	if (ret)
2173		goto out_putdev;
2174
2175	if (write) {
2176		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2177			pkt_err(pd, "not enough memory for buffers\n");
2178			ret = -ENOMEM;
2179			goto out_putdev;
2180		}
2181		pkt_info(pd, "%lukB available on disc\n", lba << 1);
2182	}
2183
2184	return 0;
2185
2186out_putdev:
2187	blkdev_put(bdev, FMODE_READ | FMODE_EXCL);
2188out:
2189	return ret;
2190}
2191
2192/*
2193 * called when the device is closed. makes sure that the device flushes
2194 * the internal cache before we close.
2195 */
2196static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2197{
2198	if (flush && pkt_flush_cache(pd))
2199		pkt_dbg(1, pd, "not flushing cache\n");
2200
2201	pkt_lock_door(pd, 0);
2202
2203	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2204	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2205
2206	pkt_shrink_pktlist(pd);
2207}
2208
2209static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2210{
2211	if (dev_minor >= MAX_WRITERS)
2212		return NULL;
2213
2214	dev_minor = array_index_nospec(dev_minor, MAX_WRITERS);
2215	return pkt_devs[dev_minor];
2216}
2217
2218static int pkt_open(struct block_device *bdev, fmode_t mode)
2219{
2220	struct pktcdvd_device *pd = NULL;
2221	int ret;
2222
2223	mutex_lock(&pktcdvd_mutex);
2224	mutex_lock(&ctl_mutex);
2225	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2226	if (!pd) {
2227		ret = -ENODEV;
2228		goto out;
2229	}
2230	BUG_ON(pd->refcnt < 0);
2231
2232	pd->refcnt++;
2233	if (pd->refcnt > 1) {
2234		if ((mode & FMODE_WRITE) &&
2235		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
2236			ret = -EBUSY;
2237			goto out_dec;
2238		}
2239	} else {
2240		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2241		if (ret)
2242			goto out_dec;
2243		/*
2244		 * needed here as well, since ext2 (among others) may change
2245		 * the blocksize at mount time
2246		 */
2247		set_blocksize(bdev, CD_FRAMESIZE);
2248	}
2249
2250	mutex_unlock(&ctl_mutex);
2251	mutex_unlock(&pktcdvd_mutex);
2252	return 0;
2253
2254out_dec:
2255	pd->refcnt--;
2256out:
2257	mutex_unlock(&ctl_mutex);
2258	mutex_unlock(&pktcdvd_mutex);
2259	return ret;
2260}
2261
2262static void pkt_close(struct gendisk *disk, fmode_t mode)
2263{
2264	struct pktcdvd_device *pd = disk->private_data;
2265
2266	mutex_lock(&pktcdvd_mutex);
2267	mutex_lock(&ctl_mutex);
2268	pd->refcnt--;
2269	BUG_ON(pd->refcnt < 0);
2270	if (pd->refcnt == 0) {
2271		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2272		pkt_release_dev(pd, flush);
2273	}
2274	mutex_unlock(&ctl_mutex);
2275	mutex_unlock(&pktcdvd_mutex);
2276}
2277
2278
2279static void pkt_end_io_read_cloned(struct bio *bio)
2280{
2281	struct packet_stacked_data *psd = bio->bi_private;
2282	struct pktcdvd_device *pd = psd->pd;
2283
2284	psd->bio->bi_status = bio->bi_status;
2285	bio_put(bio);
2286	bio_endio(psd->bio);
2287	mempool_free(psd, &psd_pool);
2288	pkt_bio_finished(pd);
2289}
2290
2291static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio)
2292{
2293	struct bio *cloned_bio =
2294		bio_alloc_clone(pd->bdev, bio, GFP_NOIO, &pkt_bio_set);
2295	struct packet_stacked_data *psd = mempool_alloc(&psd_pool, GFP_NOIO);
2296
2297	psd->pd = pd;
2298	psd->bio = bio;
 
2299	cloned_bio->bi_private = psd;
2300	cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2301	pd->stats.secs_r += bio_sectors(bio);
2302	pkt_queue_bio(pd, cloned_bio);
2303}
2304
2305static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
2306{
2307	struct pktcdvd_device *pd = q->queuedata;
2308	sector_t zone;
2309	struct packet_data *pkt;
2310	int was_empty, blocked_bio;
2311	struct pkt_rb_node *node;
2312
2313	zone = get_zone(bio->bi_iter.bi_sector, pd);
2314
2315	/*
2316	 * If we find a matching packet in state WAITING or READ_WAIT, we can
2317	 * just append this bio to that packet.
2318	 */
2319	spin_lock(&pd->cdrw.active_list_lock);
2320	blocked_bio = 0;
2321	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2322		if (pkt->sector == zone) {
2323			spin_lock(&pkt->lock);
2324			if ((pkt->state == PACKET_WAITING_STATE) ||
2325			    (pkt->state == PACKET_READ_WAIT_STATE)) {
2326				bio_list_add(&pkt->orig_bios, bio);
2327				pkt->write_size +=
2328					bio->bi_iter.bi_size / CD_FRAMESIZE;
2329				if ((pkt->write_size >= pkt->frames) &&
2330				    (pkt->state == PACKET_WAITING_STATE)) {
2331					atomic_inc(&pkt->run_sm);
2332					wake_up(&pd->wqueue);
2333				}
2334				spin_unlock(&pkt->lock);
2335				spin_unlock(&pd->cdrw.active_list_lock);
2336				return;
2337			} else {
2338				blocked_bio = 1;
2339			}
2340			spin_unlock(&pkt->lock);
2341		}
2342	}
2343	spin_unlock(&pd->cdrw.active_list_lock);
2344
2345	/*
2346	 * Test if there is enough room left in the bio work queue
2347	 * (queue size >= congestion on mark).
2348	 * If not, wait till the work queue size is below the congestion off mark.
2349	 */
2350	spin_lock(&pd->lock);
2351	if (pd->write_congestion_on > 0
2352	    && pd->bio_queue_size >= pd->write_congestion_on) {
2353		struct wait_bit_queue_entry wqe;
2354
2355		init_wait_var_entry(&wqe, &pd->congested, 0);
2356		for (;;) {
2357			prepare_to_wait_event(__var_waitqueue(&pd->congested),
2358					      &wqe.wq_entry,
2359					      TASK_UNINTERRUPTIBLE);
2360			if (pd->bio_queue_size <= pd->write_congestion_off)
2361				break;
2362			pd->congested = true;
2363			spin_unlock(&pd->lock);
2364			schedule();
2365			spin_lock(&pd->lock);
2366		}
2367	}
2368	spin_unlock(&pd->lock);
2369
2370	/*
2371	 * No matching packet found. Store the bio in the work queue.
2372	 */
2373	node = mempool_alloc(&pd->rb_pool, GFP_NOIO);
2374	node->bio = bio;
2375	spin_lock(&pd->lock);
2376	BUG_ON(pd->bio_queue_size < 0);
2377	was_empty = (pd->bio_queue_size == 0);
2378	pkt_rbtree_insert(pd, node);
2379	spin_unlock(&pd->lock);
2380
2381	/*
2382	 * Wake up the worker thread.
2383	 */
2384	atomic_set(&pd->scan_queue, 1);
2385	if (was_empty) {
2386		/* This wake_up is required for correct operation */
2387		wake_up(&pd->wqueue);
2388	} else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2389		/*
2390		 * This wake up is not required for correct operation,
2391		 * but improves performance in some cases.
2392		 */
2393		wake_up(&pd->wqueue);
2394	}
2395}
2396
2397static void pkt_submit_bio(struct bio *bio)
2398{
2399	struct pktcdvd_device *pd = bio->bi_bdev->bd_disk->queue->queuedata;
 
2400	struct bio *split;
2401
2402	bio = bio_split_to_limits(bio);
2403	if (!bio)
2404		return;
 
 
 
 
2405
2406	pkt_dbg(2, pd, "start = %6llx stop = %6llx\n",
2407		(unsigned long long)bio->bi_iter.bi_sector,
2408		(unsigned long long)bio_end_sector(bio));
2409
2410	/*
2411	 * Clone READ bios so we can have our own bi_end_io callback.
2412	 */
2413	if (bio_data_dir(bio) == READ) {
2414		pkt_make_request_read(pd, bio);
2415		return;
2416	}
2417
2418	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2419		pkt_notice(pd, "WRITE for ro device (%llu)\n",
2420			   (unsigned long long)bio->bi_iter.bi_sector);
2421		goto end_io;
2422	}
2423
2424	if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) {
2425		pkt_err(pd, "wrong bio size\n");
2426		goto end_io;
2427	}
2428
2429	do {
2430		sector_t zone = get_zone(bio->bi_iter.bi_sector, pd);
2431		sector_t last_zone = get_zone(bio_end_sector(bio) - 1, pd);
2432
2433		if (last_zone != zone) {
2434			BUG_ON(last_zone != zone + pd->settings.size);
2435
2436			split = bio_split(bio, last_zone -
2437					  bio->bi_iter.bi_sector,
2438					  GFP_NOIO, &pkt_bio_set);
2439			bio_chain(split, bio);
2440		} else {
2441			split = bio;
2442		}
2443
2444		pkt_make_request_write(bio->bi_bdev->bd_disk->queue, split);
2445	} while (split != bio);
2446
2447	return;
2448end_io:
2449	bio_io_error(bio);
 
2450}
2451
2452static void pkt_init_queue(struct pktcdvd_device *pd)
2453{
2454	struct request_queue *q = pd->disk->queue;
2455
2456	blk_queue_logical_block_size(q, CD_FRAMESIZE);
2457	blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2458	q->queuedata = pd;
2459}
2460
2461static int pkt_seq_show(struct seq_file *m, void *p)
2462{
2463	struct pktcdvd_device *pd = m->private;
2464	char *msg;
 
2465	int states[PACKET_NUM_STATES];
2466
2467	seq_printf(m, "Writer %s mapped to %pg:\n", pd->name, pd->bdev);
 
2468
2469	seq_printf(m, "\nSettings:\n");
2470	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2471
2472	if (pd->settings.write_type == 0)
2473		msg = "Packet";
2474	else
2475		msg = "Unknown";
2476	seq_printf(m, "\twrite type:\t\t%s\n", msg);
2477
2478	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2479	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2480
2481	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2482
2483	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2484		msg = "Mode 1";
2485	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2486		msg = "Mode 2";
2487	else
2488		msg = "Unknown";
2489	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2490
2491	seq_printf(m, "\nStatistics:\n");
2492	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2493	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2494	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2495	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2496	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2497
2498	seq_printf(m, "\nMisc:\n");
2499	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2500	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2501	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2502	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2503	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2504	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2505
2506	seq_printf(m, "\nQueue state:\n");
2507	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2508	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2509	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2510
2511	pkt_count_states(pd, states);
2512	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2513		   states[0], states[1], states[2], states[3], states[4], states[5]);
2514
2515	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2516			pd->write_congestion_off,
2517			pd->write_congestion_on);
2518	return 0;
2519}
2520
2521static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2522{
2523	int i;
 
 
2524	struct block_device *bdev;
2525	struct scsi_device *sdev;
2526
2527	if (pd->pkt_dev == dev) {
2528		pkt_err(pd, "recursive setup not allowed\n");
2529		return -EBUSY;
2530	}
2531	for (i = 0; i < MAX_WRITERS; i++) {
2532		struct pktcdvd_device *pd2 = pkt_devs[i];
2533		if (!pd2)
2534			continue;
2535		if (pd2->bdev->bd_dev == dev) {
2536			pkt_err(pd, "%pg already setup\n", pd2->bdev);
 
2537			return -EBUSY;
2538		}
2539		if (pd2->pkt_dev == dev) {
2540			pkt_err(pd, "can't chain pktcdvd devices\n");
2541			return -EBUSY;
2542		}
2543	}
2544
2545	bdev = blkdev_get_by_dev(dev, FMODE_READ | FMODE_NDELAY, NULL);
2546	if (IS_ERR(bdev))
2547		return PTR_ERR(bdev);
2548	sdev = scsi_device_from_queue(bdev->bd_disk->queue);
2549	if (!sdev) {
 
 
2550		blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2551		return -EINVAL;
2552	}
2553	put_device(&sdev->sdev_gendev);
2554
2555	/* This is safe, since we have a reference from open(). */
2556	__module_get(THIS_MODULE);
2557
2558	pd->bdev = bdev;
2559	set_blocksize(bdev, CD_FRAMESIZE);
2560
2561	pkt_init_queue(pd);
2562
2563	atomic_set(&pd->cdrw.pending_bios, 0);
2564	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2565	if (IS_ERR(pd->cdrw.thread)) {
2566		pkt_err(pd, "can't start kernel thread\n");
 
2567		goto out_mem;
2568	}
2569
2570	proc_create_single_data(pd->name, 0, pkt_proc, pkt_seq_show, pd);
2571	pkt_dbg(1, pd, "writer mapped to %pg\n", bdev);
2572	return 0;
2573
2574out_mem:
2575	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2576	/* This is safe: open() is still holding a reference. */
2577	module_put(THIS_MODULE);
2578	return -ENOMEM;
2579}
2580
2581static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2582{
2583	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2584	int ret;
2585
2586	pkt_dbg(2, pd, "cmd %x, dev %d:%d\n",
2587		cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2588
2589	mutex_lock(&pktcdvd_mutex);
2590	switch (cmd) {
2591	case CDROMEJECT:
2592		/*
2593		 * The door gets locked when the device is opened, so we
2594		 * have to unlock it or else the eject command fails.
2595		 */
2596		if (pd->refcnt == 1)
2597			pkt_lock_door(pd, 0);
2598		fallthrough;
2599	/*
2600	 * forward selected CDROM ioctls to CD-ROM, for UDF
2601	 */
2602	case CDROMMULTISESSION:
2603	case CDROMREADTOCENTRY:
2604	case CDROM_LAST_WRITTEN:
2605	case CDROM_SEND_PACKET:
2606	case SCSI_IOCTL_SEND_COMMAND:
2607		if (!bdev->bd_disk->fops->ioctl)
2608			ret = -ENOTTY;
2609		else
2610			ret = bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
2611		break;
 
2612	default:
2613		pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd);
2614		ret = -ENOTTY;
2615	}
2616	mutex_unlock(&pktcdvd_mutex);
2617
2618	return ret;
2619}
2620
2621static unsigned int pkt_check_events(struct gendisk *disk,
2622				     unsigned int clearing)
2623{
2624	struct pktcdvd_device *pd = disk->private_data;
2625	struct gendisk *attached_disk;
2626
2627	if (!pd)
2628		return 0;
2629	if (!pd->bdev)
2630		return 0;
2631	attached_disk = pd->bdev->bd_disk;
2632	if (!attached_disk || !attached_disk->fops->check_events)
2633		return 0;
2634	return attached_disk->fops->check_events(attached_disk, clearing);
2635}
2636
2637static char *pkt_devnode(struct gendisk *disk, umode_t *mode)
2638{
2639	return kasprintf(GFP_KERNEL, "pktcdvd/%s", disk->disk_name);
2640}
2641
2642static const struct block_device_operations pktcdvd_ops = {
2643	.owner =		THIS_MODULE,
2644	.submit_bio =		pkt_submit_bio,
2645	.open =			pkt_open,
2646	.release =		pkt_close,
2647	.ioctl =		pkt_ioctl,
2648	.compat_ioctl =		blkdev_compat_ptr_ioctl,
2649	.check_events =		pkt_check_events,
2650	.devnode =		pkt_devnode,
2651};
2652
2653/*
2654 * Set up mapping from pktcdvd device to CD-ROM device.
2655 */
2656static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2657{
2658	int idx;
2659	int ret = -ENOMEM;
2660	struct pktcdvd_device *pd;
2661	struct gendisk *disk;
2662
2663	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2664
2665	for (idx = 0; idx < MAX_WRITERS; idx++)
2666		if (!pkt_devs[idx])
2667			break;
2668	if (idx == MAX_WRITERS) {
2669		pr_err("max %d writers supported\n", MAX_WRITERS);
2670		ret = -EBUSY;
2671		goto out_mutex;
2672	}
2673
2674	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2675	if (!pd)
2676		goto out_mutex;
2677
2678	ret = mempool_init_kmalloc_pool(&pd->rb_pool, PKT_RB_POOL_SIZE,
2679					sizeof(struct pkt_rb_node));
2680	if (ret)
2681		goto out_mem;
2682
2683	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2684	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2685	spin_lock_init(&pd->cdrw.active_list_lock);
2686
2687	spin_lock_init(&pd->lock);
2688	spin_lock_init(&pd->iosched.lock);
2689	bio_list_init(&pd->iosched.read_queue);
2690	bio_list_init(&pd->iosched.write_queue);
2691	sprintf(pd->name, DRIVER_NAME"%d", idx);
2692	init_waitqueue_head(&pd->wqueue);
2693	pd->bio_queue = RB_ROOT;
2694
2695	pd->write_congestion_on  = write_congestion_on;
2696	pd->write_congestion_off = write_congestion_off;
2697
2698	ret = -ENOMEM;
2699	disk = blk_alloc_disk(NUMA_NO_NODE);
2700	if (!disk)
2701		goto out_mem;
2702	pd->disk = disk;
2703	disk->major = pktdev_major;
2704	disk->first_minor = idx;
2705	disk->minors = 1;
2706	disk->fops = &pktcdvd_ops;
2707	disk->flags = GENHD_FL_REMOVABLE | GENHD_FL_NO_PART;
2708	strcpy(disk->disk_name, pd->name);
2709	disk->private_data = pd;
 
 
 
2710
2711	pd->pkt_dev = MKDEV(pktdev_major, idx);
2712	ret = pkt_new_dev(pd, dev);
2713	if (ret)
2714		goto out_mem2;
2715
2716	/* inherit events of the host device */
2717	disk->events = pd->bdev->bd_disk->events;
2718
2719	ret = add_disk(disk);
2720	if (ret)
2721		goto out_mem2;
2722
2723	pkt_sysfs_dev_new(pd);
2724	pkt_debugfs_dev_new(pd);
2725
2726	pkt_devs[idx] = pd;
2727	if (pkt_dev)
2728		*pkt_dev = pd->pkt_dev;
2729
2730	mutex_unlock(&ctl_mutex);
2731	return 0;
2732
2733out_mem2:
2734	put_disk(disk);
2735out_mem:
2736	mempool_exit(&pd->rb_pool);
2737	kfree(pd);
2738out_mutex:
2739	mutex_unlock(&ctl_mutex);
2740	pr_err("setup of pktcdvd device failed\n");
2741	return ret;
2742}
2743
2744/*
2745 * Tear down mapping from pktcdvd device to CD-ROM device.
2746 */
2747static int pkt_remove_dev(dev_t pkt_dev)
2748{
2749	struct pktcdvd_device *pd;
2750	int idx;
2751	int ret = 0;
2752
2753	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2754
2755	for (idx = 0; idx < MAX_WRITERS; idx++) {
2756		pd = pkt_devs[idx];
2757		if (pd && (pd->pkt_dev == pkt_dev))
2758			break;
2759	}
2760	if (idx == MAX_WRITERS) {
2761		pr_debug("dev not setup\n");
2762		ret = -ENXIO;
2763		goto out;
2764	}
2765
2766	if (pd->refcnt > 0) {
2767		ret = -EBUSY;
2768		goto out;
2769	}
2770	if (!IS_ERR(pd->cdrw.thread))
2771		kthread_stop(pd->cdrw.thread);
2772
2773	pkt_devs[idx] = NULL;
2774
2775	pkt_debugfs_dev_remove(pd);
2776	pkt_sysfs_dev_remove(pd);
2777
2778	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2779
2780	remove_proc_entry(pd->name, pkt_proc);
2781	pkt_dbg(1, pd, "writer unmapped\n");
2782
2783	del_gendisk(pd->disk);
 
2784	put_disk(pd->disk);
2785
2786	mempool_exit(&pd->rb_pool);
2787	kfree(pd);
2788
2789	/* This is safe: open() is still holding a reference. */
2790	module_put(THIS_MODULE);
2791
2792out:
2793	mutex_unlock(&ctl_mutex);
2794	return ret;
2795}
2796
2797static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2798{
2799	struct pktcdvd_device *pd;
2800
2801	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2802
2803	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2804	if (pd) {
2805		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2806		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2807	} else {
2808		ctrl_cmd->dev = 0;
2809		ctrl_cmd->pkt_dev = 0;
2810	}
2811	ctrl_cmd->num_devices = MAX_WRITERS;
2812
2813	mutex_unlock(&ctl_mutex);
2814}
2815
2816static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2817{
2818	void __user *argp = (void __user *)arg;
2819	struct pkt_ctrl_command ctrl_cmd;
2820	int ret = 0;
2821	dev_t pkt_dev = 0;
2822
2823	if (cmd != PACKET_CTRL_CMD)
2824		return -ENOTTY;
2825
2826	if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2827		return -EFAULT;
2828
2829	switch (ctrl_cmd.command) {
2830	case PKT_CTRL_CMD_SETUP:
2831		if (!capable(CAP_SYS_ADMIN))
2832			return -EPERM;
2833		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2834		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2835		break;
2836	case PKT_CTRL_CMD_TEARDOWN:
2837		if (!capable(CAP_SYS_ADMIN))
2838			return -EPERM;
2839		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2840		break;
2841	case PKT_CTRL_CMD_STATUS:
2842		pkt_get_status(&ctrl_cmd);
2843		break;
2844	default:
2845		return -ENOTTY;
2846	}
2847
2848	if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2849		return -EFAULT;
2850	return ret;
2851}
2852
2853#ifdef CONFIG_COMPAT
2854static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2855{
2856	return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2857}
2858#endif
2859
2860static const struct file_operations pkt_ctl_fops = {
2861	.open		= nonseekable_open,
2862	.unlocked_ioctl	= pkt_ctl_ioctl,
2863#ifdef CONFIG_COMPAT
2864	.compat_ioctl	= pkt_ctl_compat_ioctl,
2865#endif
2866	.owner		= THIS_MODULE,
2867	.llseek		= no_llseek,
2868};
2869
2870static struct miscdevice pkt_misc = {
2871	.minor 		= MISC_DYNAMIC_MINOR,
2872	.name  		= DRIVER_NAME,
2873	.nodename	= "pktcdvd/control",
2874	.fops  		= &pkt_ctl_fops
2875};
2876
2877static int __init pkt_init(void)
2878{
2879	int ret;
2880
2881	mutex_init(&ctl_mutex);
2882
2883	ret = mempool_init_kmalloc_pool(&psd_pool, PSD_POOL_SIZE,
2884				    sizeof(struct packet_stacked_data));
2885	if (ret)
2886		return ret;
2887	ret = bioset_init(&pkt_bio_set, BIO_POOL_SIZE, 0, 0);
2888	if (ret) {
2889		mempool_exit(&psd_pool);
2890		return ret;
2891	}
2892
2893	ret = register_blkdev(pktdev_major, DRIVER_NAME);
2894	if (ret < 0) {
2895		pr_err("unable to register block device\n");
2896		goto out2;
2897	}
2898	if (!pktdev_major)
2899		pktdev_major = ret;
2900
2901	ret = pkt_sysfs_init();
2902	if (ret)
2903		goto out;
2904
2905	pkt_debugfs_init();
2906
2907	ret = misc_register(&pkt_misc);
2908	if (ret) {
2909		pr_err("unable to register misc device\n");
2910		goto out_misc;
2911	}
2912
2913	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
2914
2915	return 0;
2916
2917out_misc:
2918	pkt_debugfs_cleanup();
2919	pkt_sysfs_cleanup();
2920out:
2921	unregister_blkdev(pktdev_major, DRIVER_NAME);
2922out2:
2923	mempool_exit(&psd_pool);
2924	bioset_exit(&pkt_bio_set);
2925	return ret;
2926}
2927
2928static void __exit pkt_exit(void)
2929{
2930	remove_proc_entry("driver/"DRIVER_NAME, NULL);
2931	misc_deregister(&pkt_misc);
2932
2933	pkt_debugfs_cleanup();
2934	pkt_sysfs_cleanup();
2935
2936	unregister_blkdev(pktdev_major, DRIVER_NAME);
2937	mempool_exit(&psd_pool);
2938	bioset_exit(&pkt_bio_set);
2939}
2940
2941MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
2942MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
2943MODULE_LICENSE("GPL");
2944
2945module_init(pkt_init);
2946module_exit(pkt_exit);