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   1/*
   2 * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
   3 * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
   4 * Copyright (C) 2006 Thomas Maier <balagi@justmail.de>
   5 *
   6 * May be copied or modified under the terms of the GNU General Public
   7 * License.  See linux/COPYING for more information.
   8 *
   9 * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
  10 * DVD-RAM devices.
  11 *
  12 * Theory of operation:
  13 *
  14 * At the lowest level, there is the standard driver for the CD/DVD device,
  15 * typically ide-cd.c or sr.c. This driver can handle read and write requests,
  16 * but it doesn't know anything about the special restrictions that apply to
  17 * packet writing. One restriction is that write requests must be aligned to
  18 * packet boundaries on the physical media, and the size of a write request
  19 * must be equal to the packet size. Another restriction is that a
  20 * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
  21 * command, if the previous command was a write.
  22 *
  23 * The purpose of the packet writing driver is to hide these restrictions from
  24 * higher layers, such as file systems, and present a block device that can be
  25 * randomly read and written using 2kB-sized blocks.
  26 *
  27 * The lowest layer in the packet writing driver is the packet I/O scheduler.
  28 * Its data is defined by the struct packet_iosched and includes two bio
  29 * queues with pending read and write requests. These queues are processed
  30 * by the pkt_iosched_process_queue() function. The write requests in this
  31 * queue are already properly aligned and sized. This layer is responsible for
  32 * issuing the flush cache commands and scheduling the I/O in a good order.
  33 *
  34 * The next layer transforms unaligned write requests to aligned writes. This
  35 * transformation requires reading missing pieces of data from the underlying
  36 * block device, assembling the pieces to full packets and queuing them to the
  37 * packet I/O scheduler.
  38 *
  39 * At the top layer there is a custom make_request_fn function that forwards
  40 * read requests directly to the iosched queue and puts write requests in the
  41 * unaligned write queue. A kernel thread performs the necessary read
  42 * gathering to convert the unaligned writes to aligned writes and then feeds
  43 * them to the packet I/O scheduler.
  44 *
  45 *************************************************************************/
  46
 
 
  47#include <linux/pktcdvd.h>
  48#include <linux/module.h>
  49#include <linux/types.h>
  50#include <linux/kernel.h>
  51#include <linux/compat.h>
  52#include <linux/kthread.h>
  53#include <linux/errno.h>
  54#include <linux/spinlock.h>
  55#include <linux/file.h>
  56#include <linux/proc_fs.h>
  57#include <linux/seq_file.h>
  58#include <linux/miscdevice.h>
  59#include <linux/freezer.h>
  60#include <linux/mutex.h>
  61#include <linux/slab.h>
  62#include <scsi/scsi_cmnd.h>
  63#include <scsi/scsi_ioctl.h>
  64#include <scsi/scsi.h>
  65#include <linux/debugfs.h>
  66#include <linux/device.h>
  67
  68#include <asm/uaccess.h>
  69
  70#define DRIVER_NAME	"pktcdvd"
  71
  72#if PACKET_DEBUG
  73#define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  74#else
  75#define DPRINTK(fmt, args...)
  76#endif
  77
  78#if PACKET_DEBUG > 1
  79#define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  80#else
  81#define VPRINTK(fmt, args...)
  82#endif
 
 
 
 
  83
  84#define MAX_SPEED 0xffff
  85
  86#define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  87
  88static DEFINE_MUTEX(pktcdvd_mutex);
  89static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  90static struct proc_dir_entry *pkt_proc;
  91static int pktdev_major;
  92static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
  93static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
  94static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
  95static mempool_t *psd_pool;
  96
  97static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
  98static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
  99
 100/* forward declaration */
 101static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
 102static int pkt_remove_dev(dev_t pkt_dev);
 103static int pkt_seq_show(struct seq_file *m, void *p);
 104
 105
 
 
 
 106
 107/*
 108 * create and register a pktcdvd kernel object.
 109 */
 110static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
 111					const char* name,
 112					struct kobject* parent,
 113					struct kobj_type* ktype)
 114{
 115	struct pktcdvd_kobj *p;
 116	int error;
 117
 118	p = kzalloc(sizeof(*p), GFP_KERNEL);
 119	if (!p)
 120		return NULL;
 121	p->pd = pd;
 122	error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
 123	if (error) {
 124		kobject_put(&p->kobj);
 125		return NULL;
 126	}
 127	kobject_uevent(&p->kobj, KOBJ_ADD);
 128	return p;
 129}
 130/*
 131 * remove a pktcdvd kernel object.
 132 */
 133static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 134{
 135	if (p)
 136		kobject_put(&p->kobj);
 137}
 138/*
 139 * default release function for pktcdvd kernel objects.
 140 */
 141static void pkt_kobj_release(struct kobject *kobj)
 142{
 143	kfree(to_pktcdvdkobj(kobj));
 144}
 145
 146
 147/**********************************************************
 148 *
 149 * sysfs interface for pktcdvd
 150 * by (C) 2006  Thomas Maier <balagi@justmail.de>
 151 *
 152 **********************************************************/
 153
 154#define DEF_ATTR(_obj,_name,_mode) \
 155	static struct attribute _obj = { .name = _name, .mode = _mode }
 156
 157/**********************************************************
 158  /sys/class/pktcdvd/pktcdvd[0-7]/
 159                     stat/reset
 160                     stat/packets_started
 161                     stat/packets_finished
 162                     stat/kb_written
 163                     stat/kb_read
 164                     stat/kb_read_gather
 165                     write_queue/size
 166                     write_queue/congestion_off
 167                     write_queue/congestion_on
 168 **********************************************************/
 169
 170DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 171DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 172DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 173DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 174DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 175DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 176
 177static struct attribute *kobj_pkt_attrs_stat[] = {
 178	&kobj_pkt_attr_st1,
 179	&kobj_pkt_attr_st2,
 180	&kobj_pkt_attr_st3,
 181	&kobj_pkt_attr_st4,
 182	&kobj_pkt_attr_st5,
 183	&kobj_pkt_attr_st6,
 184	NULL
 185};
 186
 187DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 188DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 189DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 190
 191static struct attribute *kobj_pkt_attrs_wqueue[] = {
 192	&kobj_pkt_attr_wq1,
 193	&kobj_pkt_attr_wq2,
 194	&kobj_pkt_attr_wq3,
 195	NULL
 196};
 197
 198static ssize_t kobj_pkt_show(struct kobject *kobj,
 199			struct attribute *attr, char *data)
 200{
 201	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 202	int n = 0;
 203	int v;
 204	if (strcmp(attr->name, "packets_started") == 0) {
 205		n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 206
 207	} else if (strcmp(attr->name, "packets_finished") == 0) {
 208		n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 209
 210	} else if (strcmp(attr->name, "kb_written") == 0) {
 211		n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 212
 213	} else if (strcmp(attr->name, "kb_read") == 0) {
 214		n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 215
 216	} else if (strcmp(attr->name, "kb_read_gather") == 0) {
 217		n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 218
 219	} else if (strcmp(attr->name, "size") == 0) {
 220		spin_lock(&pd->lock);
 221		v = pd->bio_queue_size;
 222		spin_unlock(&pd->lock);
 223		n = sprintf(data, "%d\n", v);
 224
 225	} else if (strcmp(attr->name, "congestion_off") == 0) {
 226		spin_lock(&pd->lock);
 227		v = pd->write_congestion_off;
 228		spin_unlock(&pd->lock);
 229		n = sprintf(data, "%d\n", v);
 230
 231	} else if (strcmp(attr->name, "congestion_on") == 0) {
 232		spin_lock(&pd->lock);
 233		v = pd->write_congestion_on;
 234		spin_unlock(&pd->lock);
 235		n = sprintf(data, "%d\n", v);
 236	}
 237	return n;
 238}
 239
 240static void init_write_congestion_marks(int* lo, int* hi)
 241{
 242	if (*hi > 0) {
 243		*hi = max(*hi, 500);
 244		*hi = min(*hi, 1000000);
 245		if (*lo <= 0)
 246			*lo = *hi - 100;
 247		else {
 248			*lo = min(*lo, *hi - 100);
 249			*lo = max(*lo, 100);
 250		}
 251	} else {
 252		*hi = -1;
 253		*lo = -1;
 254	}
 255}
 256
 257static ssize_t kobj_pkt_store(struct kobject *kobj,
 258			struct attribute *attr,
 259			const char *data, size_t len)
 260{
 261	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 262	int val;
 263
 264	if (strcmp(attr->name, "reset") == 0 && len > 0) {
 265		pd->stats.pkt_started = 0;
 266		pd->stats.pkt_ended = 0;
 267		pd->stats.secs_w = 0;
 268		pd->stats.secs_rg = 0;
 269		pd->stats.secs_r = 0;
 270
 271	} else if (strcmp(attr->name, "congestion_off") == 0
 272		   && sscanf(data, "%d", &val) == 1) {
 273		spin_lock(&pd->lock);
 274		pd->write_congestion_off = val;
 275		init_write_congestion_marks(&pd->write_congestion_off,
 276					&pd->write_congestion_on);
 277		spin_unlock(&pd->lock);
 278
 279	} else if (strcmp(attr->name, "congestion_on") == 0
 280		   && sscanf(data, "%d", &val) == 1) {
 281		spin_lock(&pd->lock);
 282		pd->write_congestion_on = val;
 283		init_write_congestion_marks(&pd->write_congestion_off,
 284					&pd->write_congestion_on);
 285		spin_unlock(&pd->lock);
 286	}
 287	return len;
 288}
 289
 290static const struct sysfs_ops kobj_pkt_ops = {
 291	.show = kobj_pkt_show,
 292	.store = kobj_pkt_store
 293};
 294static struct kobj_type kobj_pkt_type_stat = {
 295	.release = pkt_kobj_release,
 296	.sysfs_ops = &kobj_pkt_ops,
 297	.default_attrs = kobj_pkt_attrs_stat
 298};
 299static struct kobj_type kobj_pkt_type_wqueue = {
 300	.release = pkt_kobj_release,
 301	.sysfs_ops = &kobj_pkt_ops,
 302	.default_attrs = kobj_pkt_attrs_wqueue
 303};
 304
 305static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 306{
 307	if (class_pktcdvd) {
 308		pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
 309					"%s", pd->name);
 310		if (IS_ERR(pd->dev))
 311			pd->dev = NULL;
 312	}
 313	if (pd->dev) {
 314		pd->kobj_stat = pkt_kobj_create(pd, "stat",
 315					&pd->dev->kobj,
 316					&kobj_pkt_type_stat);
 317		pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 318					&pd->dev->kobj,
 319					&kobj_pkt_type_wqueue);
 320	}
 321}
 322
 323static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 324{
 325	pkt_kobj_remove(pd->kobj_stat);
 326	pkt_kobj_remove(pd->kobj_wqueue);
 327	if (class_pktcdvd)
 328		device_unregister(pd->dev);
 329}
 330
 331
 332/********************************************************************
 333  /sys/class/pktcdvd/
 334                     add            map block device
 335                     remove         unmap packet dev
 336                     device_map     show mappings
 337 *******************************************************************/
 338
 339static void class_pktcdvd_release(struct class *cls)
 340{
 341	kfree(cls);
 342}
 343static ssize_t class_pktcdvd_show_map(struct class *c,
 344					struct class_attribute *attr,
 345					char *data)
 346{
 347	int n = 0;
 348	int idx;
 349	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 350	for (idx = 0; idx < MAX_WRITERS; idx++) {
 351		struct pktcdvd_device *pd = pkt_devs[idx];
 352		if (!pd)
 353			continue;
 354		n += sprintf(data+n, "%s %u:%u %u:%u\n",
 355			pd->name,
 356			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 357			MAJOR(pd->bdev->bd_dev),
 358			MINOR(pd->bdev->bd_dev));
 359	}
 360	mutex_unlock(&ctl_mutex);
 361	return n;
 362}
 363
 364static ssize_t class_pktcdvd_store_add(struct class *c,
 365					struct class_attribute *attr,
 366					const char *buf,
 367					size_t count)
 368{
 369	unsigned int major, minor;
 370
 371	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 372		/* pkt_setup_dev() expects caller to hold reference to self */
 373		if (!try_module_get(THIS_MODULE))
 374			return -ENODEV;
 375
 376		pkt_setup_dev(MKDEV(major, minor), NULL);
 377
 378		module_put(THIS_MODULE);
 379
 380		return count;
 381	}
 382
 383	return -EINVAL;
 384}
 385
 386static ssize_t class_pktcdvd_store_remove(struct class *c,
 387					  struct class_attribute *attr,
 388					  const char *buf,
 389					size_t count)
 390{
 391	unsigned int major, minor;
 392	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 393		pkt_remove_dev(MKDEV(major, minor));
 394		return count;
 395	}
 396	return -EINVAL;
 397}
 398
 399static struct class_attribute class_pktcdvd_attrs[] = {
 400 __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 401 __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 402 __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 403 __ATTR_NULL
 404};
 405
 406
 407static int pkt_sysfs_init(void)
 408{
 409	int ret = 0;
 410
 411	/*
 412	 * create control files in sysfs
 413	 * /sys/class/pktcdvd/...
 414	 */
 415	class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 416	if (!class_pktcdvd)
 417		return -ENOMEM;
 418	class_pktcdvd->name = DRIVER_NAME;
 419	class_pktcdvd->owner = THIS_MODULE;
 420	class_pktcdvd->class_release = class_pktcdvd_release;
 421	class_pktcdvd->class_attrs = class_pktcdvd_attrs;
 422	ret = class_register(class_pktcdvd);
 423	if (ret) {
 424		kfree(class_pktcdvd);
 425		class_pktcdvd = NULL;
 426		printk(DRIVER_NAME": failed to create class pktcdvd\n");
 427		return ret;
 428	}
 429	return 0;
 430}
 431
 432static void pkt_sysfs_cleanup(void)
 433{
 434	if (class_pktcdvd)
 435		class_destroy(class_pktcdvd);
 436	class_pktcdvd = NULL;
 437}
 438
 439/********************************************************************
 440  entries in debugfs
 441
 442  /sys/kernel/debug/pktcdvd[0-7]/
 443			info
 444
 445 *******************************************************************/
 446
 447static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 448{
 449	return pkt_seq_show(m, p);
 450}
 451
 452static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 453{
 454	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 455}
 456
 457static const struct file_operations debug_fops = {
 458	.open		= pkt_debugfs_fops_open,
 459	.read		= seq_read,
 460	.llseek		= seq_lseek,
 461	.release	= single_release,
 462	.owner		= THIS_MODULE,
 463};
 464
 465static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 466{
 467	if (!pkt_debugfs_root)
 468		return;
 469	pd->dfs_f_info = NULL;
 470	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 471	if (IS_ERR(pd->dfs_d_root)) {
 472		pd->dfs_d_root = NULL;
 473		return;
 474	}
 475	pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
 476				pd->dfs_d_root, pd, &debug_fops);
 477	if (IS_ERR(pd->dfs_f_info)) {
 478		pd->dfs_f_info = NULL;
 479		return;
 480	}
 481}
 482
 483static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 484{
 485	if (!pkt_debugfs_root)
 486		return;
 487	if (pd->dfs_f_info)
 488		debugfs_remove(pd->dfs_f_info);
 489	pd->dfs_f_info = NULL;
 490	if (pd->dfs_d_root)
 491		debugfs_remove(pd->dfs_d_root);
 492	pd->dfs_d_root = NULL;
 493}
 494
 495static void pkt_debugfs_init(void)
 496{
 497	pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 498	if (IS_ERR(pkt_debugfs_root)) {
 499		pkt_debugfs_root = NULL;
 500		return;
 501	}
 502}
 503
 504static void pkt_debugfs_cleanup(void)
 505{
 506	if (!pkt_debugfs_root)
 507		return;
 508	debugfs_remove(pkt_debugfs_root);
 509	pkt_debugfs_root = NULL;
 510}
 511
 512/* ----------------------------------------------------------*/
 513
 514
 515static void pkt_bio_finished(struct pktcdvd_device *pd)
 516{
 517	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 518	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 519		VPRINTK(DRIVER_NAME": queue empty\n");
 520		atomic_set(&pd->iosched.attention, 1);
 521		wake_up(&pd->wqueue);
 522	}
 523}
 524
 525static void pkt_bio_destructor(struct bio *bio)
 526{
 527	kfree(bio->bi_io_vec);
 528	kfree(bio);
 529}
 530
 531static struct bio *pkt_bio_alloc(int nr_iovecs)
 532{
 533	struct bio_vec *bvl = NULL;
 534	struct bio *bio;
 535
 536	bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
 537	if (!bio)
 538		goto no_bio;
 539	bio_init(bio);
 540
 541	bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL);
 542	if (!bvl)
 543		goto no_bvl;
 544
 545	bio->bi_max_vecs = nr_iovecs;
 546	bio->bi_io_vec = bvl;
 547	bio->bi_destructor = pkt_bio_destructor;
 548
 549	return bio;
 550
 551 no_bvl:
 552	kfree(bio);
 553 no_bio:
 554	return NULL;
 555}
 556
 557/*
 558 * Allocate a packet_data struct
 559 */
 560static struct packet_data *pkt_alloc_packet_data(int frames)
 561{
 562	int i;
 563	struct packet_data *pkt;
 564
 565	pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 566	if (!pkt)
 567		goto no_pkt;
 568
 569	pkt->frames = frames;
 570	pkt->w_bio = pkt_bio_alloc(frames);
 571	if (!pkt->w_bio)
 572		goto no_bio;
 573
 574	for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 575		pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 576		if (!pkt->pages[i])
 577			goto no_page;
 578	}
 579
 580	spin_lock_init(&pkt->lock);
 581	bio_list_init(&pkt->orig_bios);
 582
 583	for (i = 0; i < frames; i++) {
 584		struct bio *bio = pkt_bio_alloc(1);
 585		if (!bio)
 586			goto no_rd_bio;
 
 587		pkt->r_bios[i] = bio;
 588	}
 589
 590	return pkt;
 591
 592no_rd_bio:
 593	for (i = 0; i < frames; i++) {
 594		struct bio *bio = pkt->r_bios[i];
 595		if (bio)
 596			bio_put(bio);
 597	}
 598
 599no_page:
 600	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 601		if (pkt->pages[i])
 602			__free_page(pkt->pages[i]);
 603	bio_put(pkt->w_bio);
 604no_bio:
 605	kfree(pkt);
 606no_pkt:
 607	return NULL;
 608}
 609
 610/*
 611 * Free a packet_data struct
 612 */
 613static void pkt_free_packet_data(struct packet_data *pkt)
 614{
 615	int i;
 616
 617	for (i = 0; i < pkt->frames; i++) {
 618		struct bio *bio = pkt->r_bios[i];
 619		if (bio)
 620			bio_put(bio);
 621	}
 622	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 623		__free_page(pkt->pages[i]);
 624	bio_put(pkt->w_bio);
 625	kfree(pkt);
 626}
 627
 628static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 629{
 630	struct packet_data *pkt, *next;
 631
 632	BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 633
 634	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 635		pkt_free_packet_data(pkt);
 636	}
 637	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 638}
 639
 640static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 641{
 642	struct packet_data *pkt;
 643
 644	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 645
 646	while (nr_packets > 0) {
 647		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 648		if (!pkt) {
 649			pkt_shrink_pktlist(pd);
 650			return 0;
 651		}
 652		pkt->id = nr_packets;
 653		pkt->pd = pd;
 654		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 655		nr_packets--;
 656	}
 657	return 1;
 658}
 659
 660static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 661{
 662	struct rb_node *n = rb_next(&node->rb_node);
 663	if (!n)
 664		return NULL;
 665	return rb_entry(n, struct pkt_rb_node, rb_node);
 666}
 667
 668static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 669{
 670	rb_erase(&node->rb_node, &pd->bio_queue);
 671	mempool_free(node, pd->rb_pool);
 672	pd->bio_queue_size--;
 673	BUG_ON(pd->bio_queue_size < 0);
 674}
 675
 676/*
 677 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 678 */
 679static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 680{
 681	struct rb_node *n = pd->bio_queue.rb_node;
 682	struct rb_node *next;
 683	struct pkt_rb_node *tmp;
 684
 685	if (!n) {
 686		BUG_ON(pd->bio_queue_size > 0);
 687		return NULL;
 688	}
 689
 690	for (;;) {
 691		tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 692		if (s <= tmp->bio->bi_sector)
 693			next = n->rb_left;
 694		else
 695			next = n->rb_right;
 696		if (!next)
 697			break;
 698		n = next;
 699	}
 700
 701	if (s > tmp->bio->bi_sector) {
 702		tmp = pkt_rbtree_next(tmp);
 703		if (!tmp)
 704			return NULL;
 705	}
 706	BUG_ON(s > tmp->bio->bi_sector);
 707	return tmp;
 708}
 709
 710/*
 711 * Insert a node into the pd->bio_queue rb tree.
 712 */
 713static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 714{
 715	struct rb_node **p = &pd->bio_queue.rb_node;
 716	struct rb_node *parent = NULL;
 717	sector_t s = node->bio->bi_sector;
 718	struct pkt_rb_node *tmp;
 719
 720	while (*p) {
 721		parent = *p;
 722		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 723		if (s < tmp->bio->bi_sector)
 724			p = &(*p)->rb_left;
 725		else
 726			p = &(*p)->rb_right;
 727	}
 728	rb_link_node(&node->rb_node, parent, p);
 729	rb_insert_color(&node->rb_node, &pd->bio_queue);
 730	pd->bio_queue_size++;
 731}
 732
 733/*
 734 * Send a packet_command to the underlying block device and
 735 * wait for completion.
 736 */
 737static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 738{
 739	struct request_queue *q = bdev_get_queue(pd->bdev);
 740	struct request *rq;
 741	int ret = 0;
 742
 743	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 744			     WRITE : READ, __GFP_WAIT);
 745
 746	if (cgc->buflen) {
 747		if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
 
 
 748			goto out;
 749	}
 750
 751	rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 752	memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 753
 754	rq->timeout = 60*HZ;
 755	rq->cmd_type = REQ_TYPE_BLOCK_PC;
 756	if (cgc->quiet)
 757		rq->cmd_flags |= REQ_QUIET;
 758
 759	blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 760	if (rq->errors)
 761		ret = -EIO;
 762out:
 763	blk_put_request(rq);
 764	return ret;
 765}
 766
 
 
 
 
 
 
 
 
 
 
 
 767/*
 768 * A generic sense dump / resolve mechanism should be implemented across
 769 * all ATAPI + SCSI devices.
 770 */
 771static void pkt_dump_sense(struct packet_command *cgc)
 
 772{
 773	static char *info[9] = { "No sense", "Recovered error", "Not ready",
 774				 "Medium error", "Hardware error", "Illegal request",
 775				 "Unit attention", "Data protect", "Blank check" };
 776	int i;
 777	struct request_sense *sense = cgc->sense;
 778
 779	printk(DRIVER_NAME":");
 780	for (i = 0; i < CDROM_PACKET_SIZE; i++)
 781		printk(" %02x", cgc->cmd[i]);
 782	printk(" - ");
 783
 784	if (sense == NULL) {
 785		printk("no sense\n");
 786		return;
 787	}
 788
 789	printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 790
 791	if (sense->sense_key > 8) {
 792		printk(" (INVALID)\n");
 793		return;
 794	}
 795
 796	printk(" (%s)\n", info[sense->sense_key]);
 797}
 798
 799/*
 800 * flush the drive cache to media
 801 */
 802static int pkt_flush_cache(struct pktcdvd_device *pd)
 803{
 804	struct packet_command cgc;
 805
 806	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 807	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 808	cgc.quiet = 1;
 809
 810	/*
 811	 * the IMMED bit -- we default to not setting it, although that
 812	 * would allow a much faster close, this is safer
 813	 */
 814#if 0
 815	cgc.cmd[1] = 1 << 1;
 816#endif
 817	return pkt_generic_packet(pd, &cgc);
 818}
 819
 820/*
 821 * speed is given as the normal factor, e.g. 4 for 4x
 822 */
 823static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 824				unsigned write_speed, unsigned read_speed)
 825{
 826	struct packet_command cgc;
 827	struct request_sense sense;
 828	int ret;
 829
 830	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 831	cgc.sense = &sense;
 832	cgc.cmd[0] = GPCMD_SET_SPEED;
 833	cgc.cmd[2] = (read_speed >> 8) & 0xff;
 834	cgc.cmd[3] = read_speed & 0xff;
 835	cgc.cmd[4] = (write_speed >> 8) & 0xff;
 836	cgc.cmd[5] = write_speed & 0xff;
 837
 838	if ((ret = pkt_generic_packet(pd, &cgc)))
 839		pkt_dump_sense(&cgc);
 840
 841	return ret;
 842}
 843
 844/*
 845 * Queue a bio for processing by the low-level CD device. Must be called
 846 * from process context.
 847 */
 848static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 849{
 850	spin_lock(&pd->iosched.lock);
 851	if (bio_data_dir(bio) == READ)
 852		bio_list_add(&pd->iosched.read_queue, bio);
 853	else
 854		bio_list_add(&pd->iosched.write_queue, bio);
 855	spin_unlock(&pd->iosched.lock);
 856
 857	atomic_set(&pd->iosched.attention, 1);
 858	wake_up(&pd->wqueue);
 859}
 860
 861/*
 862 * Process the queued read/write requests. This function handles special
 863 * requirements for CDRW drives:
 864 * - A cache flush command must be inserted before a read request if the
 865 *   previous request was a write.
 866 * - Switching between reading and writing is slow, so don't do it more often
 867 *   than necessary.
 868 * - Optimize for throughput at the expense of latency. This means that streaming
 869 *   writes will never be interrupted by a read, but if the drive has to seek
 870 *   before the next write, switch to reading instead if there are any pending
 871 *   read requests.
 872 * - Set the read speed according to current usage pattern. When only reading
 873 *   from the device, it's best to use the highest possible read speed, but
 874 *   when switching often between reading and writing, it's better to have the
 875 *   same read and write speeds.
 876 */
 877static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 878{
 879
 880	if (atomic_read(&pd->iosched.attention) == 0)
 881		return;
 882	atomic_set(&pd->iosched.attention, 0);
 883
 884	for (;;) {
 885		struct bio *bio;
 886		int reads_queued, writes_queued;
 887
 888		spin_lock(&pd->iosched.lock);
 889		reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 890		writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 891		spin_unlock(&pd->iosched.lock);
 892
 893		if (!reads_queued && !writes_queued)
 894			break;
 895
 896		if (pd->iosched.writing) {
 897			int need_write_seek = 1;
 898			spin_lock(&pd->iosched.lock);
 899			bio = bio_list_peek(&pd->iosched.write_queue);
 900			spin_unlock(&pd->iosched.lock);
 901			if (bio && (bio->bi_sector == pd->iosched.last_write))
 
 902				need_write_seek = 0;
 903			if (need_write_seek && reads_queued) {
 904				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 905					VPRINTK(DRIVER_NAME": write, waiting\n");
 906					break;
 907				}
 908				pkt_flush_cache(pd);
 909				pd->iosched.writing = 0;
 910			}
 911		} else {
 912			if (!reads_queued && writes_queued) {
 913				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 914					VPRINTK(DRIVER_NAME": read, waiting\n");
 915					break;
 916				}
 917				pd->iosched.writing = 1;
 918			}
 919		}
 920
 921		spin_lock(&pd->iosched.lock);
 922		if (pd->iosched.writing)
 923			bio = bio_list_pop(&pd->iosched.write_queue);
 924		else
 925			bio = bio_list_pop(&pd->iosched.read_queue);
 926		spin_unlock(&pd->iosched.lock);
 927
 928		if (!bio)
 929			continue;
 930
 931		if (bio_data_dir(bio) == READ)
 932			pd->iosched.successive_reads += bio->bi_size >> 10;
 
 933		else {
 934			pd->iosched.successive_reads = 0;
 935			pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
 936		}
 937		if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 938			if (pd->read_speed == pd->write_speed) {
 939				pd->read_speed = MAX_SPEED;
 940				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 941			}
 942		} else {
 943			if (pd->read_speed != pd->write_speed) {
 944				pd->read_speed = pd->write_speed;
 945				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 946			}
 947		}
 948
 949		atomic_inc(&pd->cdrw.pending_bios);
 950		generic_make_request(bio);
 951	}
 952}
 953
 954/*
 955 * Special care is needed if the underlying block device has a small
 956 * max_phys_segments value.
 957 */
 958static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 959{
 960	if ((pd->settings.size << 9) / CD_FRAMESIZE
 961	    <= queue_max_segments(q)) {
 962		/*
 963		 * The cdrom device can handle one segment/frame
 964		 */
 965		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 966		return 0;
 967	} else if ((pd->settings.size << 9) / PAGE_SIZE
 968		   <= queue_max_segments(q)) {
 969		/*
 970		 * We can handle this case at the expense of some extra memory
 971		 * copies during write operations
 972		 */
 973		set_bit(PACKET_MERGE_SEGS, &pd->flags);
 974		return 0;
 975	} else {
 976		printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
 977		return -EIO;
 978	}
 979}
 980
 981/*
 982 * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 983 */
 984static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 985{
 986	unsigned int copy_size = CD_FRAMESIZE;
 987
 988	while (copy_size > 0) {
 989		struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 990		void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 991			src_bvl->bv_offset + offs;
 992		void *vto = page_address(dst_page) + dst_offs;
 993		int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 994
 995		BUG_ON(len < 0);
 996		memcpy(vto, vfrom, len);
 997		kunmap_atomic(vfrom, KM_USER0);
 998
 999		seg++;
1000		offs = 0;
1001		dst_offs += len;
1002		copy_size -= len;
1003	}
1004}
1005
1006/*
1007 * Copy all data for this packet to pkt->pages[], so that
1008 * a) The number of required segments for the write bio is minimized, which
1009 *    is necessary for some scsi controllers.
1010 * b) The data can be used as cache to avoid read requests if we receive a
1011 *    new write request for the same zone.
1012 */
1013static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
1014{
1015	int f, p, offs;
1016
1017	/* Copy all data to pkt->pages[] */
1018	p = 0;
1019	offs = 0;
1020	for (f = 0; f < pkt->frames; f++) {
1021		if (bvec[f].bv_page != pkt->pages[p]) {
1022			void *vfrom = kmap_atomic(bvec[f].bv_page, KM_USER0) + bvec[f].bv_offset;
1023			void *vto = page_address(pkt->pages[p]) + offs;
1024			memcpy(vto, vfrom, CD_FRAMESIZE);
1025			kunmap_atomic(vfrom, KM_USER0);
1026			bvec[f].bv_page = pkt->pages[p];
1027			bvec[f].bv_offset = offs;
1028		} else {
1029			BUG_ON(bvec[f].bv_offset != offs);
1030		}
1031		offs += CD_FRAMESIZE;
1032		if (offs >= PAGE_SIZE) {
1033			offs = 0;
1034			p++;
1035		}
1036	}
1037}
1038
1039static void pkt_end_io_read(struct bio *bio, int err)
1040{
1041	struct packet_data *pkt = bio->bi_private;
1042	struct pktcdvd_device *pd = pkt->pd;
1043	BUG_ON(!pd);
1044
1045	VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
1046		(unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 
1047
1048	if (err)
1049		atomic_inc(&pkt->io_errors);
1050	if (atomic_dec_and_test(&pkt->io_wait)) {
1051		atomic_inc(&pkt->run_sm);
1052		wake_up(&pd->wqueue);
1053	}
1054	pkt_bio_finished(pd);
1055}
1056
1057static void pkt_end_io_packet_write(struct bio *bio, int err)
1058{
1059	struct packet_data *pkt = bio->bi_private;
1060	struct pktcdvd_device *pd = pkt->pd;
1061	BUG_ON(!pd);
1062
1063	VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1064
1065	pd->stats.pkt_ended++;
1066
1067	pkt_bio_finished(pd);
1068	atomic_dec(&pkt->io_wait);
1069	atomic_inc(&pkt->run_sm);
1070	wake_up(&pd->wqueue);
1071}
1072
1073/*
1074 * Schedule reads for the holes in a packet
1075 */
1076static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1077{
1078	int frames_read = 0;
1079	struct bio *bio;
1080	int f;
1081	char written[PACKET_MAX_SIZE];
1082
1083	BUG_ON(bio_list_empty(&pkt->orig_bios));
1084
1085	atomic_set(&pkt->io_wait, 0);
1086	atomic_set(&pkt->io_errors, 0);
1087
1088	/*
1089	 * Figure out which frames we need to read before we can write.
1090	 */
1091	memset(written, 0, sizeof(written));
1092	spin_lock(&pkt->lock);
1093	bio_list_for_each(bio, &pkt->orig_bios) {
1094		int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1095		int num_frames = bio->bi_size / CD_FRAMESIZE;
 
1096		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1097		BUG_ON(first_frame < 0);
1098		BUG_ON(first_frame + num_frames > pkt->frames);
1099		for (f = first_frame; f < first_frame + num_frames; f++)
1100			written[f] = 1;
1101	}
1102	spin_unlock(&pkt->lock);
1103
1104	if (pkt->cache_valid) {
1105		VPRINTK("pkt_gather_data: zone %llx cached\n",
1106			(unsigned long long)pkt->sector);
1107		goto out_account;
1108	}
1109
1110	/*
1111	 * Schedule reads for missing parts of the packet.
1112	 */
1113	for (f = 0; f < pkt->frames; f++) {
1114		struct bio_vec *vec;
1115
1116		int p, offset;
 
1117		if (written[f])
1118			continue;
 
1119		bio = pkt->r_bios[f];
1120		vec = bio->bi_io_vec;
1121		bio_init(bio);
1122		bio->bi_max_vecs = 1;
1123		bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1124		bio->bi_bdev = pd->bdev;
1125		bio->bi_end_io = pkt_end_io_read;
1126		bio->bi_private = pkt;
1127		bio->bi_io_vec = vec;
1128		bio->bi_destructor = pkt_bio_destructor;
1129
1130		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1131		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1132		VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1133			f, pkt->pages[p], offset);
1134		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1135			BUG();
1136
1137		atomic_inc(&pkt->io_wait);
1138		bio->bi_rw = READ;
1139		pkt_queue_bio(pd, bio);
1140		frames_read++;
1141	}
1142
1143out_account:
1144	VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1145		frames_read, (unsigned long long)pkt->sector);
1146	pd->stats.pkt_started++;
1147	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1148}
1149
1150/*
1151 * Find a packet matching zone, or the least recently used packet if
1152 * there is no match.
1153 */
1154static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1155{
1156	struct packet_data *pkt;
1157
1158	list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1159		if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1160			list_del_init(&pkt->list);
1161			if (pkt->sector != zone)
1162				pkt->cache_valid = 0;
1163			return pkt;
1164		}
1165	}
1166	BUG();
1167	return NULL;
1168}
1169
1170static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1171{
1172	if (pkt->cache_valid) {
1173		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1174	} else {
1175		list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1176	}
1177}
1178
1179/*
1180 * recover a failed write, query for relocation if possible
1181 *
1182 * returns 1 if recovery is possible, or 0 if not
1183 *
1184 */
1185static int pkt_start_recovery(struct packet_data *pkt)
1186{
1187	/*
1188	 * FIXME. We need help from the file system to implement
1189	 * recovery handling.
1190	 */
1191	return 0;
1192#if 0
1193	struct request *rq = pkt->rq;
1194	struct pktcdvd_device *pd = rq->rq_disk->private_data;
1195	struct block_device *pkt_bdev;
1196	struct super_block *sb = NULL;
1197	unsigned long old_block, new_block;
1198	sector_t new_sector;
1199
1200	pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1201	if (pkt_bdev) {
1202		sb = get_super(pkt_bdev);
1203		bdput(pkt_bdev);
1204	}
1205
1206	if (!sb)
1207		return 0;
1208
1209	if (!sb->s_op->relocate_blocks)
1210		goto out;
1211
1212	old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1213	if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1214		goto out;
1215
1216	new_sector = new_block * (CD_FRAMESIZE >> 9);
1217	pkt->sector = new_sector;
1218
1219	pkt->bio->bi_sector = new_sector;
1220	pkt->bio->bi_next = NULL;
1221	pkt->bio->bi_flags = 1 << BIO_UPTODATE;
1222	pkt->bio->bi_idx = 0;
1223
1224	BUG_ON(pkt->bio->bi_rw != REQ_WRITE);
1225	BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
1226	BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
1227	BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
1228	BUG_ON(pkt->bio->bi_private != pkt);
1229
1230	drop_super(sb);
1231	return 1;
1232
1233out:
1234	drop_super(sb);
1235	return 0;
1236#endif
1237}
1238
1239static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1240{
1241#if PACKET_DEBUG > 1
1242	static const char *state_name[] = {
1243		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1244	};
1245	enum packet_data_state old_state = pkt->state;
1246	VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
 
1247		state_name[old_state], state_name[state]);
1248#endif
1249	pkt->state = state;
1250}
1251
1252/*
1253 * Scan the work queue to see if we can start a new packet.
1254 * returns non-zero if any work was done.
1255 */
1256static int pkt_handle_queue(struct pktcdvd_device *pd)
1257{
1258	struct packet_data *pkt, *p;
1259	struct bio *bio = NULL;
1260	sector_t zone = 0; /* Suppress gcc warning */
1261	struct pkt_rb_node *node, *first_node;
1262	struct rb_node *n;
1263	int wakeup;
1264
1265	VPRINTK("handle_queue\n");
1266
1267	atomic_set(&pd->scan_queue, 0);
1268
1269	if (list_empty(&pd->cdrw.pkt_free_list)) {
1270		VPRINTK("handle_queue: no pkt\n");
1271		return 0;
1272	}
1273
1274	/*
1275	 * Try to find a zone we are not already working on.
1276	 */
1277	spin_lock(&pd->lock);
1278	first_node = pkt_rbtree_find(pd, pd->current_sector);
1279	if (!first_node) {
1280		n = rb_first(&pd->bio_queue);
1281		if (n)
1282			first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1283	}
1284	node = first_node;
1285	while (node) {
1286		bio = node->bio;
1287		zone = ZONE(bio->bi_sector, pd);
1288		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1289			if (p->sector == zone) {
1290				bio = NULL;
1291				goto try_next_bio;
1292			}
1293		}
1294		break;
1295try_next_bio:
1296		node = pkt_rbtree_next(node);
1297		if (!node) {
1298			n = rb_first(&pd->bio_queue);
1299			if (n)
1300				node = rb_entry(n, struct pkt_rb_node, rb_node);
1301		}
1302		if (node == first_node)
1303			node = NULL;
1304	}
1305	spin_unlock(&pd->lock);
1306	if (!bio) {
1307		VPRINTK("handle_queue: no bio\n");
1308		return 0;
1309	}
1310
1311	pkt = pkt_get_packet_data(pd, zone);
1312
1313	pd->current_sector = zone + pd->settings.size;
1314	pkt->sector = zone;
1315	BUG_ON(pkt->frames != pd->settings.size >> 2);
1316	pkt->write_size = 0;
1317
1318	/*
1319	 * Scan work queue for bios in the same zone and link them
1320	 * to this packet.
1321	 */
1322	spin_lock(&pd->lock);
1323	VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1324	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1325		bio = node->bio;
1326		VPRINTK("pkt_handle_queue: found zone=%llx\n",
1327			(unsigned long long)ZONE(bio->bi_sector, pd));
1328		if (ZONE(bio->bi_sector, pd) != zone)
1329			break;
1330		pkt_rbtree_erase(pd, node);
1331		spin_lock(&pkt->lock);
1332		bio_list_add(&pkt->orig_bios, bio);
1333		pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1334		spin_unlock(&pkt->lock);
1335	}
1336	/* check write congestion marks, and if bio_queue_size is
1337	   below, wake up any waiters */
1338	wakeup = (pd->write_congestion_on > 0
1339	 		&& pd->bio_queue_size <= pd->write_congestion_off);
1340	spin_unlock(&pd->lock);
1341	if (wakeup) {
1342		clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1343					BLK_RW_ASYNC);
1344	}
1345
1346	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1347	pkt_set_state(pkt, PACKET_WAITING_STATE);
1348	atomic_set(&pkt->run_sm, 1);
1349
1350	spin_lock(&pd->cdrw.active_list_lock);
1351	list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1352	spin_unlock(&pd->cdrw.active_list_lock);
1353
1354	return 1;
1355}
1356
1357/*
1358 * Assemble a bio to write one packet and queue the bio for processing
1359 * by the underlying block device.
1360 */
1361static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1362{
1363	struct bio *bio;
1364	int f;
1365	int frames_write;
1366	struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1367
 
 
 
 
 
 
 
1368	for (f = 0; f < pkt->frames; f++) {
1369		bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1370		bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
 
 
1371	}
 
1372
1373	/*
1374	 * Fill-in bvec with data from orig_bios.
1375	 */
1376	frames_write = 0;
1377	spin_lock(&pkt->lock);
1378	bio_list_for_each(bio, &pkt->orig_bios) {
1379		int segment = bio->bi_idx;
1380		int src_offs = 0;
1381		int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1382		int num_frames = bio->bi_size / CD_FRAMESIZE;
1383		BUG_ON(first_frame < 0);
1384		BUG_ON(first_frame + num_frames > pkt->frames);
1385		for (f = first_frame; f < first_frame + num_frames; f++) {
1386			struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1387
1388			while (src_offs >= src_bvl->bv_len) {
1389				src_offs -= src_bvl->bv_len;
1390				segment++;
1391				BUG_ON(segment >= bio->bi_vcnt);
1392				src_bvl = bio_iovec_idx(bio, segment);
1393			}
1394
1395			if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1396				bvec[f].bv_page = src_bvl->bv_page;
1397				bvec[f].bv_offset = src_bvl->bv_offset + src_offs;
1398			} else {
1399				pkt_copy_bio_data(bio, segment, src_offs,
1400						  bvec[f].bv_page, bvec[f].bv_offset);
1401			}
1402			src_offs += CD_FRAMESIZE;
1403			frames_write++;
1404		}
1405	}
1406	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1407	spin_unlock(&pkt->lock);
1408
1409	VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1410		frames_write, (unsigned long long)pkt->sector);
1411	BUG_ON(frames_write != pkt->write_size);
1412
1413	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1414		pkt_make_local_copy(pkt, bvec);
1415		pkt->cache_valid = 1;
1416	} else {
1417		pkt->cache_valid = 0;
1418	}
1419
1420	/* Start the write request */
1421	bio_init(pkt->w_bio);
1422	pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1423	pkt->w_bio->bi_sector = pkt->sector;
1424	pkt->w_bio->bi_bdev = pd->bdev;
1425	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1426	pkt->w_bio->bi_private = pkt;
1427	pkt->w_bio->bi_io_vec = bvec;
1428	pkt->w_bio->bi_destructor = pkt_bio_destructor;
1429	for (f = 0; f < pkt->frames; f++)
1430		if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1431			BUG();
1432	VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1433
1434	atomic_set(&pkt->io_wait, 1);
1435	pkt->w_bio->bi_rw = WRITE;
1436	pkt_queue_bio(pd, pkt->w_bio);
1437}
1438
1439static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1440{
1441	struct bio *bio;
1442
1443	if (!uptodate)
1444		pkt->cache_valid = 0;
1445
1446	/* Finish all bios corresponding to this packet */
1447	while ((bio = bio_list_pop(&pkt->orig_bios)))
1448		bio_endio(bio, uptodate ? 0 : -EIO);
1449}
1450
1451static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1452{
1453	int uptodate;
1454
1455	VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1456
1457	for (;;) {
1458		switch (pkt->state) {
1459		case PACKET_WAITING_STATE:
1460			if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1461				return;
1462
1463			pkt->sleep_time = 0;
1464			pkt_gather_data(pd, pkt);
1465			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1466			break;
1467
1468		case PACKET_READ_WAIT_STATE:
1469			if (atomic_read(&pkt->io_wait) > 0)
1470				return;
1471
1472			if (atomic_read(&pkt->io_errors) > 0) {
1473				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1474			} else {
1475				pkt_start_write(pd, pkt);
1476			}
1477			break;
1478
1479		case PACKET_WRITE_WAIT_STATE:
1480			if (atomic_read(&pkt->io_wait) > 0)
1481				return;
1482
1483			if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1484				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1485			} else {
1486				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1487			}
1488			break;
1489
1490		case PACKET_RECOVERY_STATE:
1491			if (pkt_start_recovery(pkt)) {
1492				pkt_start_write(pd, pkt);
1493			} else {
1494				VPRINTK("No recovery possible\n");
1495				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1496			}
1497			break;
1498
1499		case PACKET_FINISHED_STATE:
1500			uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1501			pkt_finish_packet(pkt, uptodate);
1502			return;
1503
1504		default:
1505			BUG();
1506			break;
1507		}
1508	}
1509}
1510
1511static void pkt_handle_packets(struct pktcdvd_device *pd)
1512{
1513	struct packet_data *pkt, *next;
1514
1515	VPRINTK("pkt_handle_packets\n");
1516
1517	/*
1518	 * Run state machine for active packets
1519	 */
1520	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1521		if (atomic_read(&pkt->run_sm) > 0) {
1522			atomic_set(&pkt->run_sm, 0);
1523			pkt_run_state_machine(pd, pkt);
1524		}
1525	}
1526
1527	/*
1528	 * Move no longer active packets to the free list
1529	 */
1530	spin_lock(&pd->cdrw.active_list_lock);
1531	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1532		if (pkt->state == PACKET_FINISHED_STATE) {
1533			list_del(&pkt->list);
1534			pkt_put_packet_data(pd, pkt);
1535			pkt_set_state(pkt, PACKET_IDLE_STATE);
1536			atomic_set(&pd->scan_queue, 1);
1537		}
1538	}
1539	spin_unlock(&pd->cdrw.active_list_lock);
1540}
1541
1542static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1543{
1544	struct packet_data *pkt;
1545	int i;
1546
1547	for (i = 0; i < PACKET_NUM_STATES; i++)
1548		states[i] = 0;
1549
1550	spin_lock(&pd->cdrw.active_list_lock);
1551	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1552		states[pkt->state]++;
1553	}
1554	spin_unlock(&pd->cdrw.active_list_lock);
1555}
1556
1557/*
1558 * kcdrwd is woken up when writes have been queued for one of our
1559 * registered devices
1560 */
1561static int kcdrwd(void *foobar)
1562{
1563	struct pktcdvd_device *pd = foobar;
1564	struct packet_data *pkt;
1565	long min_sleep_time, residue;
1566
1567	set_user_nice(current, -20);
1568	set_freezable();
1569
1570	for (;;) {
1571		DECLARE_WAITQUEUE(wait, current);
1572
1573		/*
1574		 * Wait until there is something to do
1575		 */
1576		add_wait_queue(&pd->wqueue, &wait);
1577		for (;;) {
1578			set_current_state(TASK_INTERRUPTIBLE);
1579
1580			/* Check if we need to run pkt_handle_queue */
1581			if (atomic_read(&pd->scan_queue) > 0)
1582				goto work_to_do;
1583
1584			/* Check if we need to run the state machine for some packet */
1585			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1586				if (atomic_read(&pkt->run_sm) > 0)
1587					goto work_to_do;
1588			}
1589
1590			/* Check if we need to process the iosched queues */
1591			if (atomic_read(&pd->iosched.attention) != 0)
1592				goto work_to_do;
1593
1594			/* Otherwise, go to sleep */
1595			if (PACKET_DEBUG > 1) {
1596				int states[PACKET_NUM_STATES];
1597				pkt_count_states(pd, states);
1598				VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1599					states[0], states[1], states[2], states[3],
1600					states[4], states[5]);
1601			}
1602
1603			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1604			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1605				if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1606					min_sleep_time = pkt->sleep_time;
1607			}
1608
1609			VPRINTK("kcdrwd: sleeping\n");
1610			residue = schedule_timeout(min_sleep_time);
1611			VPRINTK("kcdrwd: wake up\n");
1612
1613			/* make swsusp happy with our thread */
1614			try_to_freeze();
1615
1616			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1617				if (!pkt->sleep_time)
1618					continue;
1619				pkt->sleep_time -= min_sleep_time - residue;
1620				if (pkt->sleep_time <= 0) {
1621					pkt->sleep_time = 0;
1622					atomic_inc(&pkt->run_sm);
1623				}
1624			}
1625
1626			if (kthread_should_stop())
1627				break;
1628		}
1629work_to_do:
1630		set_current_state(TASK_RUNNING);
1631		remove_wait_queue(&pd->wqueue, &wait);
1632
1633		if (kthread_should_stop())
1634			break;
1635
1636		/*
1637		 * if pkt_handle_queue returns true, we can queue
1638		 * another request.
1639		 */
1640		while (pkt_handle_queue(pd))
1641			;
1642
1643		/*
1644		 * Handle packet state machine
1645		 */
1646		pkt_handle_packets(pd);
1647
1648		/*
1649		 * Handle iosched queues
1650		 */
1651		pkt_iosched_process_queue(pd);
1652	}
1653
1654	return 0;
1655}
1656
1657static void pkt_print_settings(struct pktcdvd_device *pd)
1658{
1659	printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1660	printk("%u blocks, ", pd->settings.size >> 2);
1661	printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
 
1662}
1663
1664static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1665{
1666	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1667
1668	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1669	cgc->cmd[2] = page_code | (page_control << 6);
1670	cgc->cmd[7] = cgc->buflen >> 8;
1671	cgc->cmd[8] = cgc->buflen & 0xff;
1672	cgc->data_direction = CGC_DATA_READ;
1673	return pkt_generic_packet(pd, cgc);
1674}
1675
1676static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1677{
1678	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1679	memset(cgc->buffer, 0, 2);
1680	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1681	cgc->cmd[1] = 0x10;		/* PF */
1682	cgc->cmd[7] = cgc->buflen >> 8;
1683	cgc->cmd[8] = cgc->buflen & 0xff;
1684	cgc->data_direction = CGC_DATA_WRITE;
1685	return pkt_generic_packet(pd, cgc);
1686}
1687
1688static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1689{
1690	struct packet_command cgc;
1691	int ret;
1692
1693	/* set up command and get the disc info */
1694	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1695	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1696	cgc.cmd[8] = cgc.buflen = 2;
1697	cgc.quiet = 1;
1698
1699	if ((ret = pkt_generic_packet(pd, &cgc)))
1700		return ret;
1701
1702	/* not all drives have the same disc_info length, so requeue
1703	 * packet with the length the drive tells us it can supply
1704	 */
1705	cgc.buflen = be16_to_cpu(di->disc_information_length) +
1706		     sizeof(di->disc_information_length);
1707
1708	if (cgc.buflen > sizeof(disc_information))
1709		cgc.buflen = sizeof(disc_information);
1710
1711	cgc.cmd[8] = cgc.buflen;
1712	return pkt_generic_packet(pd, &cgc);
1713}
1714
1715static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1716{
1717	struct packet_command cgc;
1718	int ret;
1719
1720	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1721	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1722	cgc.cmd[1] = type & 3;
1723	cgc.cmd[4] = (track & 0xff00) >> 8;
1724	cgc.cmd[5] = track & 0xff;
1725	cgc.cmd[8] = 8;
1726	cgc.quiet = 1;
1727
1728	if ((ret = pkt_generic_packet(pd, &cgc)))
1729		return ret;
1730
1731	cgc.buflen = be16_to_cpu(ti->track_information_length) +
1732		     sizeof(ti->track_information_length);
1733
1734	if (cgc.buflen > sizeof(track_information))
1735		cgc.buflen = sizeof(track_information);
1736
1737	cgc.cmd[8] = cgc.buflen;
1738	return pkt_generic_packet(pd, &cgc);
1739}
1740
1741static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1742						long *last_written)
1743{
1744	disc_information di;
1745	track_information ti;
1746	__u32 last_track;
1747	int ret = -1;
1748
1749	if ((ret = pkt_get_disc_info(pd, &di)))
1750		return ret;
1751
1752	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1753	if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1754		return ret;
1755
1756	/* if this track is blank, try the previous. */
1757	if (ti.blank) {
1758		last_track--;
1759		if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1760			return ret;
1761	}
1762
1763	/* if last recorded field is valid, return it. */
1764	if (ti.lra_v) {
1765		*last_written = be32_to_cpu(ti.last_rec_address);
1766	} else {
1767		/* make it up instead */
1768		*last_written = be32_to_cpu(ti.track_start) +
1769				be32_to_cpu(ti.track_size);
1770		if (ti.free_blocks)
1771			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1772	}
1773	return 0;
1774}
1775
1776/*
1777 * write mode select package based on pd->settings
1778 */
1779static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1780{
1781	struct packet_command cgc;
1782	struct request_sense sense;
1783	write_param_page *wp;
1784	char buffer[128];
1785	int ret, size;
1786
1787	/* doesn't apply to DVD+RW or DVD-RAM */
1788	if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1789		return 0;
1790
1791	memset(buffer, 0, sizeof(buffer));
1792	init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1793	cgc.sense = &sense;
1794	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1795		pkt_dump_sense(&cgc);
1796		return ret;
1797	}
1798
1799	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1800	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1801	if (size > sizeof(buffer))
1802		size = sizeof(buffer);
1803
1804	/*
1805	 * now get it all
1806	 */
1807	init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1808	cgc.sense = &sense;
1809	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1810		pkt_dump_sense(&cgc);
1811		return ret;
1812	}
1813
1814	/*
1815	 * write page is offset header + block descriptor length
1816	 */
1817	wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1818
1819	wp->fp = pd->settings.fp;
1820	wp->track_mode = pd->settings.track_mode;
1821	wp->write_type = pd->settings.write_type;
1822	wp->data_block_type = pd->settings.block_mode;
1823
1824	wp->multi_session = 0;
1825
1826#ifdef PACKET_USE_LS
1827	wp->link_size = 7;
1828	wp->ls_v = 1;
1829#endif
1830
1831	if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1832		wp->session_format = 0;
1833		wp->subhdr2 = 0x20;
1834	} else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1835		wp->session_format = 0x20;
1836		wp->subhdr2 = 8;
1837#if 0
1838		wp->mcn[0] = 0x80;
1839		memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1840#endif
1841	} else {
1842		/*
1843		 * paranoia
1844		 */
1845		printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1846		return 1;
1847	}
1848	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1849
1850	cgc.buflen = cgc.cmd[8] = size;
1851	if ((ret = pkt_mode_select(pd, &cgc))) {
1852		pkt_dump_sense(&cgc);
1853		return ret;
1854	}
1855
1856	pkt_print_settings(pd);
1857	return 0;
1858}
1859
1860/*
1861 * 1 -- we can write to this track, 0 -- we can't
1862 */
1863static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1864{
1865	switch (pd->mmc3_profile) {
1866		case 0x1a: /* DVD+RW */
1867		case 0x12: /* DVD-RAM */
1868			/* The track is always writable on DVD+RW/DVD-RAM */
1869			return 1;
1870		default:
1871			break;
1872	}
1873
1874	if (!ti->packet || !ti->fp)
1875		return 0;
1876
1877	/*
1878	 * "good" settings as per Mt Fuji.
1879	 */
1880	if (ti->rt == 0 && ti->blank == 0)
1881		return 1;
1882
1883	if (ti->rt == 0 && ti->blank == 1)
1884		return 1;
1885
1886	if (ti->rt == 1 && ti->blank == 0)
1887		return 1;
1888
1889	printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1890	return 0;
1891}
1892
1893/*
1894 * 1 -- we can write to this disc, 0 -- we can't
1895 */
1896static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1897{
1898	switch (pd->mmc3_profile) {
1899		case 0x0a: /* CD-RW */
1900		case 0xffff: /* MMC3 not supported */
1901			break;
1902		case 0x1a: /* DVD+RW */
1903		case 0x13: /* DVD-RW */
1904		case 0x12: /* DVD-RAM */
1905			return 1;
1906		default:
1907			VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
 
1908			return 0;
1909	}
1910
1911	/*
1912	 * for disc type 0xff we should probably reserve a new track.
1913	 * but i'm not sure, should we leave this to user apps? probably.
1914	 */
1915	if (di->disc_type == 0xff) {
1916		printk(DRIVER_NAME": Unknown disc. No track?\n");
1917		return 0;
1918	}
1919
1920	if (di->disc_type != 0x20 && di->disc_type != 0) {
1921		printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1922		return 0;
1923	}
1924
1925	if (di->erasable == 0) {
1926		printk(DRIVER_NAME": Disc not erasable\n");
1927		return 0;
1928	}
1929
1930	if (di->border_status == PACKET_SESSION_RESERVED) {
1931		printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1932		return 0;
1933	}
1934
1935	return 1;
1936}
1937
1938static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1939{
1940	struct packet_command cgc;
1941	unsigned char buf[12];
1942	disc_information di;
1943	track_information ti;
1944	int ret, track;
1945
1946	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1947	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1948	cgc.cmd[8] = 8;
1949	ret = pkt_generic_packet(pd, &cgc);
1950	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1951
1952	memset(&di, 0, sizeof(disc_information));
1953	memset(&ti, 0, sizeof(track_information));
1954
1955	if ((ret = pkt_get_disc_info(pd, &di))) {
1956		printk("failed get_disc\n");
1957		return ret;
1958	}
1959
1960	if (!pkt_writable_disc(pd, &di))
1961		return -EROFS;
1962
1963	pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1964
1965	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1966	if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1967		printk(DRIVER_NAME": failed get_track\n");
1968		return ret;
1969	}
1970
1971	if (!pkt_writable_track(pd, &ti)) {
1972		printk(DRIVER_NAME": can't write to this track\n");
1973		return -EROFS;
1974	}
1975
1976	/*
1977	 * we keep packet size in 512 byte units, makes it easier to
1978	 * deal with request calculations.
1979	 */
1980	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1981	if (pd->settings.size == 0) {
1982		printk(DRIVER_NAME": detected zero packet size!\n");
1983		return -ENXIO;
1984	}
1985	if (pd->settings.size > PACKET_MAX_SECTORS) {
1986		printk(DRIVER_NAME": packet size is too big\n");
1987		return -EROFS;
1988	}
1989	pd->settings.fp = ti.fp;
1990	pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1991
1992	if (ti.nwa_v) {
1993		pd->nwa = be32_to_cpu(ti.next_writable);
1994		set_bit(PACKET_NWA_VALID, &pd->flags);
1995	}
1996
1997	/*
1998	 * in theory we could use lra on -RW media as well and just zero
1999	 * blocks that haven't been written yet, but in practice that
2000	 * is just a no-go. we'll use that for -R, naturally.
2001	 */
2002	if (ti.lra_v) {
2003		pd->lra = be32_to_cpu(ti.last_rec_address);
2004		set_bit(PACKET_LRA_VALID, &pd->flags);
2005	} else {
2006		pd->lra = 0xffffffff;
2007		set_bit(PACKET_LRA_VALID, &pd->flags);
2008	}
2009
2010	/*
2011	 * fine for now
2012	 */
2013	pd->settings.link_loss = 7;
2014	pd->settings.write_type = 0;	/* packet */
2015	pd->settings.track_mode = ti.track_mode;
2016
2017	/*
2018	 * mode1 or mode2 disc
2019	 */
2020	switch (ti.data_mode) {
2021		case PACKET_MODE1:
2022			pd->settings.block_mode = PACKET_BLOCK_MODE1;
2023			break;
2024		case PACKET_MODE2:
2025			pd->settings.block_mode = PACKET_BLOCK_MODE2;
2026			break;
2027		default:
2028			printk(DRIVER_NAME": unknown data mode\n");
2029			return -EROFS;
2030	}
2031	return 0;
2032}
2033
2034/*
2035 * enable/disable write caching on drive
2036 */
2037static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
2038						int set)
2039{
2040	struct packet_command cgc;
2041	struct request_sense sense;
2042	unsigned char buf[64];
2043	int ret;
2044
2045	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
2046	cgc.sense = &sense;
2047	cgc.buflen = pd->mode_offset + 12;
2048
2049	/*
2050	 * caching mode page might not be there, so quiet this command
2051	 */
2052	cgc.quiet = 1;
2053
2054	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
2055		return ret;
2056
2057	buf[pd->mode_offset + 10] |= (!!set << 2);
2058
2059	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
2060	ret = pkt_mode_select(pd, &cgc);
2061	if (ret) {
2062		printk(DRIVER_NAME": write caching control failed\n");
2063		pkt_dump_sense(&cgc);
2064	} else if (!ret && set)
2065		printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
2066	return ret;
2067}
2068
2069static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
2070{
2071	struct packet_command cgc;
2072
2073	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2074	cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
2075	cgc.cmd[4] = lockflag ? 1 : 0;
2076	return pkt_generic_packet(pd, &cgc);
2077}
2078
2079/*
2080 * Returns drive maximum write speed
2081 */
2082static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
2083						unsigned *write_speed)
2084{
2085	struct packet_command cgc;
2086	struct request_sense sense;
2087	unsigned char buf[256+18];
2088	unsigned char *cap_buf;
2089	int ret, offset;
2090
2091	cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
2092	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2093	cgc.sense = &sense;
2094
2095	ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2096	if (ret) {
2097		cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2098			     sizeof(struct mode_page_header);
2099		ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2100		if (ret) {
2101			pkt_dump_sense(&cgc);
2102			return ret;
2103		}
2104	}
2105
2106	offset = 20;			    /* Obsoleted field, used by older drives */
2107	if (cap_buf[1] >= 28)
2108		offset = 28;		    /* Current write speed selected */
2109	if (cap_buf[1] >= 30) {
2110		/* If the drive reports at least one "Logical Unit Write
2111		 * Speed Performance Descriptor Block", use the information
2112		 * in the first block. (contains the highest speed)
2113		 */
2114		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2115		if (num_spdb > 0)
2116			offset = 34;
2117	}
2118
2119	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2120	return 0;
2121}
2122
2123/* These tables from cdrecord - I don't have orange book */
2124/* standard speed CD-RW (1-4x) */
2125static char clv_to_speed[16] = {
2126	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2127	   0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2128};
2129/* high speed CD-RW (-10x) */
2130static char hs_clv_to_speed[16] = {
2131	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2132	   0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2133};
2134/* ultra high speed CD-RW */
2135static char us_clv_to_speed[16] = {
2136	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2137	   0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2138};
2139
2140/*
2141 * reads the maximum media speed from ATIP
2142 */
2143static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2144						unsigned *speed)
2145{
2146	struct packet_command cgc;
2147	struct request_sense sense;
2148	unsigned char buf[64];
2149	unsigned int size, st, sp;
2150	int ret;
2151
2152	init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2153	cgc.sense = &sense;
2154	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2155	cgc.cmd[1] = 2;
2156	cgc.cmd[2] = 4; /* READ ATIP */
2157	cgc.cmd[8] = 2;
2158	ret = pkt_generic_packet(pd, &cgc);
2159	if (ret) {
2160		pkt_dump_sense(&cgc);
2161		return ret;
2162	}
2163	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2164	if (size > sizeof(buf))
2165		size = sizeof(buf);
2166
2167	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2168	cgc.sense = &sense;
2169	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2170	cgc.cmd[1] = 2;
2171	cgc.cmd[2] = 4;
2172	cgc.cmd[8] = size;
2173	ret = pkt_generic_packet(pd, &cgc);
2174	if (ret) {
2175		pkt_dump_sense(&cgc);
2176		return ret;
2177	}
2178
2179	if (!(buf[6] & 0x40)) {
2180		printk(DRIVER_NAME": Disc type is not CD-RW\n");
2181		return 1;
2182	}
2183	if (!(buf[6] & 0x4)) {
2184		printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2185		return 1;
2186	}
2187
2188	st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2189
2190	sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2191
2192	/* Info from cdrecord */
2193	switch (st) {
2194		case 0: /* standard speed */
2195			*speed = clv_to_speed[sp];
2196			break;
2197		case 1: /* high speed */
2198			*speed = hs_clv_to_speed[sp];
2199			break;
2200		case 2: /* ultra high speed */
2201			*speed = us_clv_to_speed[sp];
2202			break;
2203		default:
2204			printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2205			return 1;
2206	}
2207	if (*speed) {
2208		printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2209		return 0;
2210	} else {
2211		printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2212		return 1;
2213	}
2214}
2215
2216static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2217{
2218	struct packet_command cgc;
2219	struct request_sense sense;
2220	int ret;
2221
2222	VPRINTK(DRIVER_NAME": Performing OPC\n");
2223
2224	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2225	cgc.sense = &sense;
2226	cgc.timeout = 60*HZ;
2227	cgc.cmd[0] = GPCMD_SEND_OPC;
2228	cgc.cmd[1] = 1;
2229	if ((ret = pkt_generic_packet(pd, &cgc)))
2230		pkt_dump_sense(&cgc);
2231	return ret;
2232}
2233
2234static int pkt_open_write(struct pktcdvd_device *pd)
2235{
2236	int ret;
2237	unsigned int write_speed, media_write_speed, read_speed;
2238
2239	if ((ret = pkt_probe_settings(pd))) {
2240		VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2241		return ret;
2242	}
2243
2244	if ((ret = pkt_set_write_settings(pd))) {
2245		DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2246		return -EIO;
2247	}
2248
2249	pkt_write_caching(pd, USE_WCACHING);
2250
2251	if ((ret = pkt_get_max_speed(pd, &write_speed)))
2252		write_speed = 16 * 177;
2253	switch (pd->mmc3_profile) {
2254		case 0x13: /* DVD-RW */
2255		case 0x1a: /* DVD+RW */
2256		case 0x12: /* DVD-RAM */
2257			DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2258			break;
2259		default:
2260			if ((ret = pkt_media_speed(pd, &media_write_speed)))
2261				media_write_speed = 16;
2262			write_speed = min(write_speed, media_write_speed * 177);
2263			DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2264			break;
2265	}
2266	read_speed = write_speed;
2267
2268	if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2269		DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2270		return -EIO;
2271	}
2272	pd->write_speed = write_speed;
2273	pd->read_speed = read_speed;
2274
2275	if ((ret = pkt_perform_opc(pd))) {
2276		DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2277	}
2278
2279	return 0;
2280}
2281
2282/*
2283 * called at open time.
2284 */
2285static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2286{
2287	int ret;
2288	long lba;
2289	struct request_queue *q;
2290
2291	/*
2292	 * We need to re-open the cdrom device without O_NONBLOCK to be able
2293	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2294	 * so bdget() can't fail.
2295	 */
2296	bdget(pd->bdev->bd_dev);
2297	if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2298		goto out;
2299
2300	if ((ret = pkt_get_last_written(pd, &lba))) {
2301		printk(DRIVER_NAME": pkt_get_last_written failed\n");
2302		goto out_putdev;
2303	}
2304
2305	set_capacity(pd->disk, lba << 2);
2306	set_capacity(pd->bdev->bd_disk, lba << 2);
2307	bd_set_size(pd->bdev, (loff_t)lba << 11);
2308
2309	q = bdev_get_queue(pd->bdev);
2310	if (write) {
2311		if ((ret = pkt_open_write(pd)))
2312			goto out_putdev;
2313		/*
2314		 * Some CDRW drives can not handle writes larger than one packet,
2315		 * even if the size is a multiple of the packet size.
2316		 */
2317		spin_lock_irq(q->queue_lock);
2318		blk_queue_max_hw_sectors(q, pd->settings.size);
2319		spin_unlock_irq(q->queue_lock);
2320		set_bit(PACKET_WRITABLE, &pd->flags);
2321	} else {
2322		pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2323		clear_bit(PACKET_WRITABLE, &pd->flags);
2324	}
2325
2326	if ((ret = pkt_set_segment_merging(pd, q)))
2327		goto out_putdev;
2328
2329	if (write) {
2330		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2331			printk(DRIVER_NAME": not enough memory for buffers\n");
2332			ret = -ENOMEM;
2333			goto out_putdev;
2334		}
2335		printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2336	}
2337
2338	return 0;
2339
2340out_putdev:
2341	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2342out:
2343	return ret;
2344}
2345
2346/*
2347 * called when the device is closed. makes sure that the device flushes
2348 * the internal cache before we close.
2349 */
2350static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2351{
2352	if (flush && pkt_flush_cache(pd))
2353		DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2354
2355	pkt_lock_door(pd, 0);
2356
2357	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2358	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2359
2360	pkt_shrink_pktlist(pd);
2361}
2362
2363static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2364{
2365	if (dev_minor >= MAX_WRITERS)
2366		return NULL;
2367	return pkt_devs[dev_minor];
2368}
2369
2370static int pkt_open(struct block_device *bdev, fmode_t mode)
2371{
2372	struct pktcdvd_device *pd = NULL;
2373	int ret;
2374
2375	VPRINTK(DRIVER_NAME": entering open\n");
2376
2377	mutex_lock(&pktcdvd_mutex);
2378	mutex_lock(&ctl_mutex);
2379	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2380	if (!pd) {
2381		ret = -ENODEV;
2382		goto out;
2383	}
2384	BUG_ON(pd->refcnt < 0);
2385
2386	pd->refcnt++;
2387	if (pd->refcnt > 1) {
2388		if ((mode & FMODE_WRITE) &&
2389		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
2390			ret = -EBUSY;
2391			goto out_dec;
2392		}
2393	} else {
2394		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2395		if (ret)
2396			goto out_dec;
2397		/*
2398		 * needed here as well, since ext2 (among others) may change
2399		 * the blocksize at mount time
2400		 */
2401		set_blocksize(bdev, CD_FRAMESIZE);
2402	}
2403
2404	mutex_unlock(&ctl_mutex);
2405	mutex_unlock(&pktcdvd_mutex);
2406	return 0;
2407
2408out_dec:
2409	pd->refcnt--;
2410out:
2411	VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2412	mutex_unlock(&ctl_mutex);
2413	mutex_unlock(&pktcdvd_mutex);
2414	return ret;
2415}
2416
2417static int pkt_close(struct gendisk *disk, fmode_t mode)
2418{
2419	struct pktcdvd_device *pd = disk->private_data;
2420	int ret = 0;
2421
2422	mutex_lock(&pktcdvd_mutex);
2423	mutex_lock(&ctl_mutex);
2424	pd->refcnt--;
2425	BUG_ON(pd->refcnt < 0);
2426	if (pd->refcnt == 0) {
2427		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2428		pkt_release_dev(pd, flush);
2429	}
2430	mutex_unlock(&ctl_mutex);
2431	mutex_unlock(&pktcdvd_mutex);
2432	return ret;
2433}
2434
2435
2436static void pkt_end_io_read_cloned(struct bio *bio, int err)
2437{
2438	struct packet_stacked_data *psd = bio->bi_private;
2439	struct pktcdvd_device *pd = psd->pd;
2440
2441	bio_put(bio);
2442	bio_endio(psd->bio, err);
2443	mempool_free(psd, psd_pool);
2444	pkt_bio_finished(pd);
2445}
2446
2447static int pkt_make_request(struct request_queue *q, struct bio *bio)
2448{
2449	struct pktcdvd_device *pd;
2450	char b[BDEVNAME_SIZE];
 
 
 
 
 
 
 
 
 
 
 
 
 
2451	sector_t zone;
2452	struct packet_data *pkt;
2453	int was_empty, blocked_bio;
2454	struct pkt_rb_node *node;
2455
2456	pd = q->queuedata;
2457	if (!pd) {
2458		printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2459		goto end_io;
2460	}
2461
2462	/*
2463	 * Clone READ bios so we can have our own bi_end_io callback.
2464	 */
2465	if (bio_data_dir(bio) == READ) {
2466		struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2467		struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2468
2469		psd->pd = pd;
2470		psd->bio = bio;
2471		cloned_bio->bi_bdev = pd->bdev;
2472		cloned_bio->bi_private = psd;
2473		cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2474		pd->stats.secs_r += bio->bi_size >> 9;
2475		pkt_queue_bio(pd, cloned_bio);
2476		return 0;
2477	}
2478
2479	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2480		printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2481			pd->name, (unsigned long long)bio->bi_sector);
2482		goto end_io;
2483	}
2484
2485	if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2486		printk(DRIVER_NAME": wrong bio size\n");
2487		goto end_io;
2488	}
2489
2490	blk_queue_bounce(q, &bio);
2491
2492	zone = ZONE(bio->bi_sector, pd);
2493	VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2494		(unsigned long long)bio->bi_sector,
2495		(unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2496
2497	/* Check if we have to split the bio */
2498	{
2499		struct bio_pair *bp;
2500		sector_t last_zone;
2501		int first_sectors;
2502
2503		last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2504		if (last_zone != zone) {
2505			BUG_ON(last_zone != zone + pd->settings.size);
2506			first_sectors = last_zone - bio->bi_sector;
2507			bp = bio_split(bio, first_sectors);
2508			BUG_ON(!bp);
2509			pkt_make_request(q, &bp->bio1);
2510			pkt_make_request(q, &bp->bio2);
2511			bio_pair_release(bp);
2512			return 0;
2513		}
2514	}
2515
2516	/*
2517	 * If we find a matching packet in state WAITING or READ_WAIT, we can
2518	 * just append this bio to that packet.
2519	 */
2520	spin_lock(&pd->cdrw.active_list_lock);
2521	blocked_bio = 0;
2522	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2523		if (pkt->sector == zone) {
2524			spin_lock(&pkt->lock);
2525			if ((pkt->state == PACKET_WAITING_STATE) ||
2526			    (pkt->state == PACKET_READ_WAIT_STATE)) {
2527				bio_list_add(&pkt->orig_bios, bio);
2528				pkt->write_size += bio->bi_size / CD_FRAMESIZE;
 
2529				if ((pkt->write_size >= pkt->frames) &&
2530				    (pkt->state == PACKET_WAITING_STATE)) {
2531					atomic_inc(&pkt->run_sm);
2532					wake_up(&pd->wqueue);
2533				}
2534				spin_unlock(&pkt->lock);
2535				spin_unlock(&pd->cdrw.active_list_lock);
2536				return 0;
2537			} else {
2538				blocked_bio = 1;
2539			}
2540			spin_unlock(&pkt->lock);
2541		}
2542	}
2543	spin_unlock(&pd->cdrw.active_list_lock);
2544
2545 	/*
2546	 * Test if there is enough room left in the bio work queue
2547	 * (queue size >= congestion on mark).
2548	 * If not, wait till the work queue size is below the congestion off mark.
2549	 */
2550	spin_lock(&pd->lock);
2551	if (pd->write_congestion_on > 0
2552	    && pd->bio_queue_size >= pd->write_congestion_on) {
2553		set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2554		do {
2555			spin_unlock(&pd->lock);
2556			congestion_wait(BLK_RW_ASYNC, HZ);
2557			spin_lock(&pd->lock);
2558		} while(pd->bio_queue_size > pd->write_congestion_off);
2559	}
2560	spin_unlock(&pd->lock);
2561
2562	/*
2563	 * No matching packet found. Store the bio in the work queue.
2564	 */
2565	node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2566	node->bio = bio;
2567	spin_lock(&pd->lock);
2568	BUG_ON(pd->bio_queue_size < 0);
2569	was_empty = (pd->bio_queue_size == 0);
2570	pkt_rbtree_insert(pd, node);
2571	spin_unlock(&pd->lock);
2572
2573	/*
2574	 * Wake up the worker thread.
2575	 */
2576	atomic_set(&pd->scan_queue, 1);
2577	if (was_empty) {
2578		/* This wake_up is required for correct operation */
2579		wake_up(&pd->wqueue);
2580	} else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2581		/*
2582		 * This wake up is not required for correct operation,
2583		 * but improves performance in some cases.
2584		 */
2585		wake_up(&pd->wqueue);
2586	}
2587	return 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2588end_io:
2589	bio_io_error(bio);
2590	return 0;
2591}
2592
2593
2594
2595static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2596			  struct bio_vec *bvec)
2597{
2598	struct pktcdvd_device *pd = q->queuedata;
2599	sector_t zone = ZONE(bmd->bi_sector, pd);
2600	int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2601	int remaining = (pd->settings.size << 9) - used;
2602	int remaining2;
2603
2604	/*
2605	 * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2606	 * boundary, pkt_make_request() will split the bio.
2607	 */
2608	remaining2 = PAGE_SIZE - bmd->bi_size;
2609	remaining = max(remaining, remaining2);
2610
2611	BUG_ON(remaining < 0);
2612	return remaining;
2613}
2614
2615static void pkt_init_queue(struct pktcdvd_device *pd)
2616{
2617	struct request_queue *q = pd->disk->queue;
2618
2619	blk_queue_make_request(q, pkt_make_request);
2620	blk_queue_logical_block_size(q, CD_FRAMESIZE);
2621	blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2622	blk_queue_merge_bvec(q, pkt_merge_bvec);
2623	q->queuedata = pd;
2624}
2625
2626static int pkt_seq_show(struct seq_file *m, void *p)
2627{
2628	struct pktcdvd_device *pd = m->private;
2629	char *msg;
2630	char bdev_buf[BDEVNAME_SIZE];
2631	int states[PACKET_NUM_STATES];
2632
2633	seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2634		   bdevname(pd->bdev, bdev_buf));
2635
2636	seq_printf(m, "\nSettings:\n");
2637	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2638
2639	if (pd->settings.write_type == 0)
2640		msg = "Packet";
2641	else
2642		msg = "Unknown";
2643	seq_printf(m, "\twrite type:\t\t%s\n", msg);
2644
2645	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2646	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2647
2648	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2649
2650	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2651		msg = "Mode 1";
2652	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2653		msg = "Mode 2";
2654	else
2655		msg = "Unknown";
2656	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2657
2658	seq_printf(m, "\nStatistics:\n");
2659	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2660	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2661	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2662	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2663	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2664
2665	seq_printf(m, "\nMisc:\n");
2666	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2667	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2668	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2669	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2670	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2671	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2672
2673	seq_printf(m, "\nQueue state:\n");
2674	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2675	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2676	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2677
2678	pkt_count_states(pd, states);
2679	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2680		   states[0], states[1], states[2], states[3], states[4], states[5]);
2681
2682	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2683			pd->write_congestion_off,
2684			pd->write_congestion_on);
2685	return 0;
2686}
2687
2688static int pkt_seq_open(struct inode *inode, struct file *file)
2689{
2690	return single_open(file, pkt_seq_show, PDE(inode)->data);
2691}
2692
2693static const struct file_operations pkt_proc_fops = {
2694	.open	= pkt_seq_open,
2695	.read	= seq_read,
2696	.llseek	= seq_lseek,
2697	.release = single_release
2698};
2699
2700static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2701{
2702	int i;
2703	int ret = 0;
2704	char b[BDEVNAME_SIZE];
2705	struct block_device *bdev;
2706
2707	if (pd->pkt_dev == dev) {
2708		printk(DRIVER_NAME": Recursive setup not allowed\n");
2709		return -EBUSY;
2710	}
2711	for (i = 0; i < MAX_WRITERS; i++) {
2712		struct pktcdvd_device *pd2 = pkt_devs[i];
2713		if (!pd2)
2714			continue;
2715		if (pd2->bdev->bd_dev == dev) {
2716			printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
 
2717			return -EBUSY;
2718		}
2719		if (pd2->pkt_dev == dev) {
2720			printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2721			return -EBUSY;
2722		}
2723	}
2724
2725	bdev = bdget(dev);
2726	if (!bdev)
2727		return -ENOMEM;
2728	ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2729	if (ret)
2730		return ret;
2731
2732	/* This is safe, since we have a reference from open(). */
2733	__module_get(THIS_MODULE);
2734
2735	pd->bdev = bdev;
2736	set_blocksize(bdev, CD_FRAMESIZE);
2737
2738	pkt_init_queue(pd);
2739
2740	atomic_set(&pd->cdrw.pending_bios, 0);
2741	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2742	if (IS_ERR(pd->cdrw.thread)) {
2743		printk(DRIVER_NAME": can't start kernel thread\n");
2744		ret = -ENOMEM;
2745		goto out_mem;
2746	}
2747
2748	proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2749	DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2750	return 0;
2751
2752out_mem:
2753	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2754	/* This is safe: open() is still holding a reference. */
2755	module_put(THIS_MODULE);
2756	return ret;
2757}
2758
2759static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2760{
2761	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2762	int ret;
2763
2764	VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2765		MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2766
2767	mutex_lock(&pktcdvd_mutex);
2768	switch (cmd) {
2769	case CDROMEJECT:
2770		/*
2771		 * The door gets locked when the device is opened, so we
2772		 * have to unlock it or else the eject command fails.
2773		 */
2774		if (pd->refcnt == 1)
2775			pkt_lock_door(pd, 0);
2776		/* fallthru */
2777	/*
2778	 * forward selected CDROM ioctls to CD-ROM, for UDF
2779	 */
2780	case CDROMMULTISESSION:
2781	case CDROMREADTOCENTRY:
2782	case CDROM_LAST_WRITTEN:
2783	case CDROM_SEND_PACKET:
2784	case SCSI_IOCTL_SEND_COMMAND:
2785		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2786		break;
2787
2788	default:
2789		VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2790		ret = -ENOTTY;
2791	}
2792	mutex_unlock(&pktcdvd_mutex);
2793
2794	return ret;
2795}
2796
2797static unsigned int pkt_check_events(struct gendisk *disk,
2798				     unsigned int clearing)
2799{
2800	struct pktcdvd_device *pd = disk->private_data;
2801	struct gendisk *attached_disk;
2802
2803	if (!pd)
2804		return 0;
2805	if (!pd->bdev)
2806		return 0;
2807	attached_disk = pd->bdev->bd_disk;
2808	if (!attached_disk || !attached_disk->fops->check_events)
2809		return 0;
2810	return attached_disk->fops->check_events(attached_disk, clearing);
2811}
2812
2813static const struct block_device_operations pktcdvd_ops = {
2814	.owner =		THIS_MODULE,
2815	.open =			pkt_open,
2816	.release =		pkt_close,
2817	.ioctl =		pkt_ioctl,
2818	.check_events =		pkt_check_events,
2819};
2820
2821static char *pktcdvd_devnode(struct gendisk *gd, mode_t *mode)
2822{
2823	return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2824}
2825
2826/*
2827 * Set up mapping from pktcdvd device to CD-ROM device.
2828 */
2829static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2830{
2831	int idx;
2832	int ret = -ENOMEM;
2833	struct pktcdvd_device *pd;
2834	struct gendisk *disk;
2835
2836	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2837
2838	for (idx = 0; idx < MAX_WRITERS; idx++)
2839		if (!pkt_devs[idx])
2840			break;
2841	if (idx == MAX_WRITERS) {
2842		printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2843		ret = -EBUSY;
2844		goto out_mutex;
2845	}
2846
2847	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2848	if (!pd)
2849		goto out_mutex;
2850
2851	pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2852						  sizeof(struct pkt_rb_node));
2853	if (!pd->rb_pool)
2854		goto out_mem;
2855
2856	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2857	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2858	spin_lock_init(&pd->cdrw.active_list_lock);
2859
2860	spin_lock_init(&pd->lock);
2861	spin_lock_init(&pd->iosched.lock);
2862	bio_list_init(&pd->iosched.read_queue);
2863	bio_list_init(&pd->iosched.write_queue);
2864	sprintf(pd->name, DRIVER_NAME"%d", idx);
2865	init_waitqueue_head(&pd->wqueue);
2866	pd->bio_queue = RB_ROOT;
2867
2868	pd->write_congestion_on  = write_congestion_on;
2869	pd->write_congestion_off = write_congestion_off;
2870
2871	disk = alloc_disk(1);
2872	if (!disk)
2873		goto out_mem;
2874	pd->disk = disk;
2875	disk->major = pktdev_major;
2876	disk->first_minor = idx;
2877	disk->fops = &pktcdvd_ops;
2878	disk->flags = GENHD_FL_REMOVABLE;
2879	strcpy(disk->disk_name, pd->name);
2880	disk->devnode = pktcdvd_devnode;
2881	disk->private_data = pd;
2882	disk->queue = blk_alloc_queue(GFP_KERNEL);
2883	if (!disk->queue)
2884		goto out_mem2;
2885
2886	pd->pkt_dev = MKDEV(pktdev_major, idx);
2887	ret = pkt_new_dev(pd, dev);
2888	if (ret)
2889		goto out_new_dev;
2890
2891	/* inherit events of the host device */
2892	disk->events = pd->bdev->bd_disk->events;
2893	disk->async_events = pd->bdev->bd_disk->async_events;
2894
2895	add_disk(disk);
2896
2897	pkt_sysfs_dev_new(pd);
2898	pkt_debugfs_dev_new(pd);
2899
2900	pkt_devs[idx] = pd;
2901	if (pkt_dev)
2902		*pkt_dev = pd->pkt_dev;
2903
2904	mutex_unlock(&ctl_mutex);
2905	return 0;
2906
2907out_new_dev:
2908	blk_cleanup_queue(disk->queue);
2909out_mem2:
2910	put_disk(disk);
2911out_mem:
2912	if (pd->rb_pool)
2913		mempool_destroy(pd->rb_pool);
2914	kfree(pd);
2915out_mutex:
2916	mutex_unlock(&ctl_mutex);
2917	printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2918	return ret;
2919}
2920
2921/*
2922 * Tear down mapping from pktcdvd device to CD-ROM device.
2923 */
2924static int pkt_remove_dev(dev_t pkt_dev)
2925{
2926	struct pktcdvd_device *pd;
2927	int idx;
2928	int ret = 0;
2929
2930	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2931
2932	for (idx = 0; idx < MAX_WRITERS; idx++) {
2933		pd = pkt_devs[idx];
2934		if (pd && (pd->pkt_dev == pkt_dev))
2935			break;
2936	}
2937	if (idx == MAX_WRITERS) {
2938		DPRINTK(DRIVER_NAME": dev not setup\n");
2939		ret = -ENXIO;
2940		goto out;
2941	}
2942
2943	if (pd->refcnt > 0) {
2944		ret = -EBUSY;
2945		goto out;
2946	}
2947	if (!IS_ERR(pd->cdrw.thread))
2948		kthread_stop(pd->cdrw.thread);
2949
2950	pkt_devs[idx] = NULL;
2951
2952	pkt_debugfs_dev_remove(pd);
2953	pkt_sysfs_dev_remove(pd);
2954
2955	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2956
2957	remove_proc_entry(pd->name, pkt_proc);
2958	DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2959
2960	del_gendisk(pd->disk);
2961	blk_cleanup_queue(pd->disk->queue);
2962	put_disk(pd->disk);
2963
2964	mempool_destroy(pd->rb_pool);
2965	kfree(pd);
2966
2967	/* This is safe: open() is still holding a reference. */
2968	module_put(THIS_MODULE);
2969
2970out:
2971	mutex_unlock(&ctl_mutex);
2972	return ret;
2973}
2974
2975static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2976{
2977	struct pktcdvd_device *pd;
2978
2979	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2980
2981	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2982	if (pd) {
2983		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2984		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2985	} else {
2986		ctrl_cmd->dev = 0;
2987		ctrl_cmd->pkt_dev = 0;
2988	}
2989	ctrl_cmd->num_devices = MAX_WRITERS;
2990
2991	mutex_unlock(&ctl_mutex);
2992}
2993
2994static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2995{
2996	void __user *argp = (void __user *)arg;
2997	struct pkt_ctrl_command ctrl_cmd;
2998	int ret = 0;
2999	dev_t pkt_dev = 0;
3000
3001	if (cmd != PACKET_CTRL_CMD)
3002		return -ENOTTY;
3003
3004	if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
3005		return -EFAULT;
3006
3007	switch (ctrl_cmd.command) {
3008	case PKT_CTRL_CMD_SETUP:
3009		if (!capable(CAP_SYS_ADMIN))
3010			return -EPERM;
3011		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
3012		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
3013		break;
3014	case PKT_CTRL_CMD_TEARDOWN:
3015		if (!capable(CAP_SYS_ADMIN))
3016			return -EPERM;
3017		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
3018		break;
3019	case PKT_CTRL_CMD_STATUS:
3020		pkt_get_status(&ctrl_cmd);
3021		break;
3022	default:
3023		return -ENOTTY;
3024	}
3025
3026	if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
3027		return -EFAULT;
3028	return ret;
3029}
3030
3031#ifdef CONFIG_COMPAT
3032static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
3033{
3034	return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
3035}
3036#endif
3037
3038static const struct file_operations pkt_ctl_fops = {
3039	.open		= nonseekable_open,
3040	.unlocked_ioctl	= pkt_ctl_ioctl,
3041#ifdef CONFIG_COMPAT
3042	.compat_ioctl	= pkt_ctl_compat_ioctl,
3043#endif
3044	.owner		= THIS_MODULE,
3045	.llseek		= no_llseek,
3046};
3047
3048static struct miscdevice pkt_misc = {
3049	.minor 		= MISC_DYNAMIC_MINOR,
3050	.name  		= DRIVER_NAME,
3051	.nodename	= "pktcdvd/control",
3052	.fops  		= &pkt_ctl_fops
3053};
3054
3055static int __init pkt_init(void)
3056{
3057	int ret;
3058
3059	mutex_init(&ctl_mutex);
3060
3061	psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
3062					sizeof(struct packet_stacked_data));
3063	if (!psd_pool)
3064		return -ENOMEM;
3065
3066	ret = register_blkdev(pktdev_major, DRIVER_NAME);
3067	if (ret < 0) {
3068		printk(DRIVER_NAME": Unable to register block device\n");
3069		goto out2;
3070	}
3071	if (!pktdev_major)
3072		pktdev_major = ret;
3073
3074	ret = pkt_sysfs_init();
3075	if (ret)
3076		goto out;
3077
3078	pkt_debugfs_init();
3079
3080	ret = misc_register(&pkt_misc);
3081	if (ret) {
3082		printk(DRIVER_NAME": Unable to register misc device\n");
3083		goto out_misc;
3084	}
3085
3086	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
3087
3088	return 0;
3089
3090out_misc:
3091	pkt_debugfs_cleanup();
3092	pkt_sysfs_cleanup();
3093out:
3094	unregister_blkdev(pktdev_major, DRIVER_NAME);
3095out2:
3096	mempool_destroy(psd_pool);
3097	return ret;
3098}
3099
3100static void __exit pkt_exit(void)
3101{
3102	remove_proc_entry("driver/"DRIVER_NAME, NULL);
3103	misc_deregister(&pkt_misc);
3104
3105	pkt_debugfs_cleanup();
3106	pkt_sysfs_cleanup();
3107
3108	unregister_blkdev(pktdev_major, DRIVER_NAME);
3109	mempool_destroy(psd_pool);
3110}
3111
3112MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3113MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3114MODULE_LICENSE("GPL");
3115
3116module_init(pkt_init);
3117module_exit(pkt_exit);
v3.15
   1/*
   2 * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
   3 * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
   4 * Copyright (C) 2006 Thomas Maier <balagi@justmail.de>
   5 *
   6 * May be copied or modified under the terms of the GNU General Public
   7 * License.  See linux/COPYING for more information.
   8 *
   9 * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
  10 * DVD-RAM devices.
  11 *
  12 * Theory of operation:
  13 *
  14 * At the lowest level, there is the standard driver for the CD/DVD device,
  15 * typically ide-cd.c or sr.c. This driver can handle read and write requests,
  16 * but it doesn't know anything about the special restrictions that apply to
  17 * packet writing. One restriction is that write requests must be aligned to
  18 * packet boundaries on the physical media, and the size of a write request
  19 * must be equal to the packet size. Another restriction is that a
  20 * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
  21 * command, if the previous command was a write.
  22 *
  23 * The purpose of the packet writing driver is to hide these restrictions from
  24 * higher layers, such as file systems, and present a block device that can be
  25 * randomly read and written using 2kB-sized blocks.
  26 *
  27 * The lowest layer in the packet writing driver is the packet I/O scheduler.
  28 * Its data is defined by the struct packet_iosched and includes two bio
  29 * queues with pending read and write requests. These queues are processed
  30 * by the pkt_iosched_process_queue() function. The write requests in this
  31 * queue are already properly aligned and sized. This layer is responsible for
  32 * issuing the flush cache commands and scheduling the I/O in a good order.
  33 *
  34 * The next layer transforms unaligned write requests to aligned writes. This
  35 * transformation requires reading missing pieces of data from the underlying
  36 * block device, assembling the pieces to full packets and queuing them to the
  37 * packet I/O scheduler.
  38 *
  39 * At the top layer there is a custom make_request_fn function that forwards
  40 * read requests directly to the iosched queue and puts write requests in the
  41 * unaligned write queue. A kernel thread performs the necessary read
  42 * gathering to convert the unaligned writes to aligned writes and then feeds
  43 * them to the packet I/O scheduler.
  44 *
  45 *************************************************************************/
  46
  47#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  48
  49#include <linux/pktcdvd.h>
  50#include <linux/module.h>
  51#include <linux/types.h>
  52#include <linux/kernel.h>
  53#include <linux/compat.h>
  54#include <linux/kthread.h>
  55#include <linux/errno.h>
  56#include <linux/spinlock.h>
  57#include <linux/file.h>
  58#include <linux/proc_fs.h>
  59#include <linux/seq_file.h>
  60#include <linux/miscdevice.h>
  61#include <linux/freezer.h>
  62#include <linux/mutex.h>
  63#include <linux/slab.h>
  64#include <scsi/scsi_cmnd.h>
  65#include <scsi/scsi_ioctl.h>
  66#include <scsi/scsi.h>
  67#include <linux/debugfs.h>
  68#include <linux/device.h>
  69
  70#include <asm/uaccess.h>
  71
  72#define DRIVER_NAME	"pktcdvd"
  73
  74#define pkt_err(pd, fmt, ...)						\
  75	pr_err("%s: " fmt, pd->name, ##__VA_ARGS__)
  76#define pkt_notice(pd, fmt, ...)					\
  77	pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__)
  78#define pkt_info(pd, fmt, ...)						\
  79	pr_info("%s: " fmt, pd->name, ##__VA_ARGS__)
  80
  81#define pkt_dbg(level, pd, fmt, ...)					\
  82do {									\
  83	if (level == 2 && PACKET_DEBUG >= 2)				\
  84		pr_notice("%s: %s():" fmt,				\
  85			  pd->name, __func__, ##__VA_ARGS__);		\
  86	else if (level == 1 && PACKET_DEBUG >= 1)			\
  87		pr_notice("%s: " fmt, pd->name, ##__VA_ARGS__);		\
  88} while (0)
  89
  90#define MAX_SPEED 0xffff
  91
 
 
  92static DEFINE_MUTEX(pktcdvd_mutex);
  93static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  94static struct proc_dir_entry *pkt_proc;
  95static int pktdev_major;
  96static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
  97static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
  98static struct mutex ctl_mutex;	/* Serialize open/close/setup/teardown */
  99static mempool_t *psd_pool;
 100
 101static struct class	*class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
 102static struct dentry	*pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
 103
 104/* forward declaration */
 105static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
 106static int pkt_remove_dev(dev_t pkt_dev);
 107static int pkt_seq_show(struct seq_file *m, void *p);
 108
 109static sector_t get_zone(sector_t sector, struct pktcdvd_device *pd)
 110{
 111	return (sector + pd->offset) & ~(sector_t)(pd->settings.size - 1);
 112}
 113
 114/*
 115 * create and register a pktcdvd kernel object.
 116 */
 117static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
 118					const char* name,
 119					struct kobject* parent,
 120					struct kobj_type* ktype)
 121{
 122	struct pktcdvd_kobj *p;
 123	int error;
 124
 125	p = kzalloc(sizeof(*p), GFP_KERNEL);
 126	if (!p)
 127		return NULL;
 128	p->pd = pd;
 129	error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
 130	if (error) {
 131		kobject_put(&p->kobj);
 132		return NULL;
 133	}
 134	kobject_uevent(&p->kobj, KOBJ_ADD);
 135	return p;
 136}
 137/*
 138 * remove a pktcdvd kernel object.
 139 */
 140static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 141{
 142	if (p)
 143		kobject_put(&p->kobj);
 144}
 145/*
 146 * default release function for pktcdvd kernel objects.
 147 */
 148static void pkt_kobj_release(struct kobject *kobj)
 149{
 150	kfree(to_pktcdvdkobj(kobj));
 151}
 152
 153
 154/**********************************************************
 155 *
 156 * sysfs interface for pktcdvd
 157 * by (C) 2006  Thomas Maier <balagi@justmail.de>
 158 *
 159 **********************************************************/
 160
 161#define DEF_ATTR(_obj,_name,_mode) \
 162	static struct attribute _obj = { .name = _name, .mode = _mode }
 163
 164/**********************************************************
 165  /sys/class/pktcdvd/pktcdvd[0-7]/
 166                     stat/reset
 167                     stat/packets_started
 168                     stat/packets_finished
 169                     stat/kb_written
 170                     stat/kb_read
 171                     stat/kb_read_gather
 172                     write_queue/size
 173                     write_queue/congestion_off
 174                     write_queue/congestion_on
 175 **********************************************************/
 176
 177DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 178DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 179DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 180DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 181DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 182DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 183
 184static struct attribute *kobj_pkt_attrs_stat[] = {
 185	&kobj_pkt_attr_st1,
 186	&kobj_pkt_attr_st2,
 187	&kobj_pkt_attr_st3,
 188	&kobj_pkt_attr_st4,
 189	&kobj_pkt_attr_st5,
 190	&kobj_pkt_attr_st6,
 191	NULL
 192};
 193
 194DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 195DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 196DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 197
 198static struct attribute *kobj_pkt_attrs_wqueue[] = {
 199	&kobj_pkt_attr_wq1,
 200	&kobj_pkt_attr_wq2,
 201	&kobj_pkt_attr_wq3,
 202	NULL
 203};
 204
 205static ssize_t kobj_pkt_show(struct kobject *kobj,
 206			struct attribute *attr, char *data)
 207{
 208	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 209	int n = 0;
 210	int v;
 211	if (strcmp(attr->name, "packets_started") == 0) {
 212		n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 213
 214	} else if (strcmp(attr->name, "packets_finished") == 0) {
 215		n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 216
 217	} else if (strcmp(attr->name, "kb_written") == 0) {
 218		n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 219
 220	} else if (strcmp(attr->name, "kb_read") == 0) {
 221		n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 222
 223	} else if (strcmp(attr->name, "kb_read_gather") == 0) {
 224		n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 225
 226	} else if (strcmp(attr->name, "size") == 0) {
 227		spin_lock(&pd->lock);
 228		v = pd->bio_queue_size;
 229		spin_unlock(&pd->lock);
 230		n = sprintf(data, "%d\n", v);
 231
 232	} else if (strcmp(attr->name, "congestion_off") == 0) {
 233		spin_lock(&pd->lock);
 234		v = pd->write_congestion_off;
 235		spin_unlock(&pd->lock);
 236		n = sprintf(data, "%d\n", v);
 237
 238	} else if (strcmp(attr->name, "congestion_on") == 0) {
 239		spin_lock(&pd->lock);
 240		v = pd->write_congestion_on;
 241		spin_unlock(&pd->lock);
 242		n = sprintf(data, "%d\n", v);
 243	}
 244	return n;
 245}
 246
 247static void init_write_congestion_marks(int* lo, int* hi)
 248{
 249	if (*hi > 0) {
 250		*hi = max(*hi, 500);
 251		*hi = min(*hi, 1000000);
 252		if (*lo <= 0)
 253			*lo = *hi - 100;
 254		else {
 255			*lo = min(*lo, *hi - 100);
 256			*lo = max(*lo, 100);
 257		}
 258	} else {
 259		*hi = -1;
 260		*lo = -1;
 261	}
 262}
 263
 264static ssize_t kobj_pkt_store(struct kobject *kobj,
 265			struct attribute *attr,
 266			const char *data, size_t len)
 267{
 268	struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 269	int val;
 270
 271	if (strcmp(attr->name, "reset") == 0 && len > 0) {
 272		pd->stats.pkt_started = 0;
 273		pd->stats.pkt_ended = 0;
 274		pd->stats.secs_w = 0;
 275		pd->stats.secs_rg = 0;
 276		pd->stats.secs_r = 0;
 277
 278	} else if (strcmp(attr->name, "congestion_off") == 0
 279		   && sscanf(data, "%d", &val) == 1) {
 280		spin_lock(&pd->lock);
 281		pd->write_congestion_off = val;
 282		init_write_congestion_marks(&pd->write_congestion_off,
 283					&pd->write_congestion_on);
 284		spin_unlock(&pd->lock);
 285
 286	} else if (strcmp(attr->name, "congestion_on") == 0
 287		   && sscanf(data, "%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}
 296
 297static const struct sysfs_ops kobj_pkt_ops = {
 298	.show = kobj_pkt_show,
 299	.store = kobj_pkt_store
 300};
 301static struct kobj_type kobj_pkt_type_stat = {
 302	.release = pkt_kobj_release,
 303	.sysfs_ops = &kobj_pkt_ops,
 304	.default_attrs = kobj_pkt_attrs_stat
 305};
 306static struct kobj_type kobj_pkt_type_wqueue = {
 307	.release = pkt_kobj_release,
 308	.sysfs_ops = &kobj_pkt_ops,
 309	.default_attrs = kobj_pkt_attrs_wqueue
 310};
 311
 312static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 313{
 314	if (class_pktcdvd) {
 315		pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
 316					"%s", pd->name);
 317		if (IS_ERR(pd->dev))
 318			pd->dev = NULL;
 319	}
 320	if (pd->dev) {
 321		pd->kobj_stat = pkt_kobj_create(pd, "stat",
 322					&pd->dev->kobj,
 323					&kobj_pkt_type_stat);
 324		pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 325					&pd->dev->kobj,
 326					&kobj_pkt_type_wqueue);
 327	}
 328}
 329
 330static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 331{
 332	pkt_kobj_remove(pd->kobj_stat);
 333	pkt_kobj_remove(pd->kobj_wqueue);
 334	if (class_pktcdvd)
 335		device_unregister(pd->dev);
 336}
 337
 338
 339/********************************************************************
 340  /sys/class/pktcdvd/
 341                     add            map block device
 342                     remove         unmap packet dev
 343                     device_map     show mappings
 344 *******************************************************************/
 345
 346static void class_pktcdvd_release(struct class *cls)
 347{
 348	kfree(cls);
 349}
 350static ssize_t class_pktcdvd_show_map(struct class *c,
 351					struct class_attribute *attr,
 352					char *data)
 353{
 354	int n = 0;
 355	int idx;
 356	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 357	for (idx = 0; idx < MAX_WRITERS; idx++) {
 358		struct pktcdvd_device *pd = pkt_devs[idx];
 359		if (!pd)
 360			continue;
 361		n += sprintf(data+n, "%s %u:%u %u:%u\n",
 362			pd->name,
 363			MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 364			MAJOR(pd->bdev->bd_dev),
 365			MINOR(pd->bdev->bd_dev));
 366	}
 367	mutex_unlock(&ctl_mutex);
 368	return n;
 369}
 370
 371static ssize_t class_pktcdvd_store_add(struct class *c,
 372					struct class_attribute *attr,
 373					const char *buf,
 374					size_t count)
 375{
 376	unsigned int major, minor;
 377
 378	if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 379		/* pkt_setup_dev() expects caller to hold reference to self */
 380		if (!try_module_get(THIS_MODULE))
 381			return -ENODEV;
 382
 383		pkt_setup_dev(MKDEV(major, minor), NULL);
 384
 385		module_put(THIS_MODULE);
 386
 387		return count;
 388	}
 389
 390	return -EINVAL;
 391}
 392
 393static ssize_t class_pktcdvd_store_remove(struct class *c,
 394					  struct class_attribute *attr,
 395					  const char *buf,
 396					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}
 405
 406static struct class_attribute class_pktcdvd_attrs[] = {
 407 __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 408 __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 409 __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 410 __ATTR_NULL
 411};
 412
 413
 414static int pkt_sysfs_init(void)
 415{
 416	int ret = 0;
 417
 418	/*
 419	 * create control files in sysfs
 420	 * /sys/class/pktcdvd/...
 421	 */
 422	class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 423	if (!class_pktcdvd)
 424		return -ENOMEM;
 425	class_pktcdvd->name = DRIVER_NAME;
 426	class_pktcdvd->owner = THIS_MODULE;
 427	class_pktcdvd->class_release = class_pktcdvd_release;
 428	class_pktcdvd->class_attrs = class_pktcdvd_attrs;
 429	ret = class_register(class_pktcdvd);
 430	if (ret) {
 431		kfree(class_pktcdvd);
 432		class_pktcdvd = NULL;
 433		pr_err("failed to create class pktcdvd\n");
 434		return ret;
 435	}
 436	return 0;
 437}
 438
 439static void pkt_sysfs_cleanup(void)
 440{
 441	if (class_pktcdvd)
 442		class_destroy(class_pktcdvd);
 443	class_pktcdvd = NULL;
 444}
 445
 446/********************************************************************
 447  entries in debugfs
 448
 449  /sys/kernel/debug/pktcdvd[0-7]/
 450			info
 451
 452 *******************************************************************/
 453
 454static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 455{
 456	return pkt_seq_show(m, p);
 457}
 458
 459static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 460{
 461	return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 462}
 463
 464static const struct file_operations debug_fops = {
 465	.open		= pkt_debugfs_fops_open,
 466	.read		= seq_read,
 467	.llseek		= seq_lseek,
 468	.release	= single_release,
 469	.owner		= THIS_MODULE,
 470};
 471
 472static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 473{
 474	if (!pkt_debugfs_root)
 475		return;
 
 476	pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 477	if (!pd->dfs_d_root)
 
 478		return;
 479
 480	pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
 481				pd->dfs_d_root, pd, &debug_fops);
 
 
 
 
 482}
 483
 484static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 485{
 486	if (!pkt_debugfs_root)
 487		return;
 488	debugfs_remove(pd->dfs_f_info);
 489	debugfs_remove(pd->dfs_d_root);
 490	pd->dfs_f_info = NULL;
 
 
 491	pd->dfs_d_root = NULL;
 492}
 493
 494static void pkt_debugfs_init(void)
 495{
 496	pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 
 
 
 
 497}
 498
 499static void pkt_debugfs_cleanup(void)
 500{
 
 
 501	debugfs_remove(pkt_debugfs_root);
 502	pkt_debugfs_root = NULL;
 503}
 504
 505/* ----------------------------------------------------------*/
 506
 507
 508static void pkt_bio_finished(struct pktcdvd_device *pd)
 509{
 510	BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 511	if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 512		pkt_dbg(2, pd, "queue empty\n");
 513		atomic_set(&pd->iosched.attention, 1);
 514		wake_up(&pd->wqueue);
 515	}
 516}
 517
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 518/*
 519 * Allocate a packet_data struct
 520 */
 521static struct packet_data *pkt_alloc_packet_data(int frames)
 522{
 523	int i;
 524	struct packet_data *pkt;
 525
 526	pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 527	if (!pkt)
 528		goto no_pkt;
 529
 530	pkt->frames = frames;
 531	pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
 532	if (!pkt->w_bio)
 533		goto no_bio;
 534
 535	for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 536		pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 537		if (!pkt->pages[i])
 538			goto no_page;
 539	}
 540
 541	spin_lock_init(&pkt->lock);
 542	bio_list_init(&pkt->orig_bios);
 543
 544	for (i = 0; i < frames; i++) {
 545		struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
 546		if (!bio)
 547			goto no_rd_bio;
 548
 549		pkt->r_bios[i] = bio;
 550	}
 551
 552	return pkt;
 553
 554no_rd_bio:
 555	for (i = 0; i < frames; i++) {
 556		struct bio *bio = pkt->r_bios[i];
 557		if (bio)
 558			bio_put(bio);
 559	}
 560
 561no_page:
 562	for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 563		if (pkt->pages[i])
 564			__free_page(pkt->pages[i]);
 565	bio_put(pkt->w_bio);
 566no_bio:
 567	kfree(pkt);
 568no_pkt:
 569	return NULL;
 570}
 571
 572/*
 573 * Free a packet_data struct
 574 */
 575static void pkt_free_packet_data(struct packet_data *pkt)
 576{
 577	int i;
 578
 579	for (i = 0; i < pkt->frames; i++) {
 580		struct bio *bio = pkt->r_bios[i];
 581		if (bio)
 582			bio_put(bio);
 583	}
 584	for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 585		__free_page(pkt->pages[i]);
 586	bio_put(pkt->w_bio);
 587	kfree(pkt);
 588}
 589
 590static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 591{
 592	struct packet_data *pkt, *next;
 593
 594	BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 595
 596	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 597		pkt_free_packet_data(pkt);
 598	}
 599	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 600}
 601
 602static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 603{
 604	struct packet_data *pkt;
 605
 606	BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 607
 608	while (nr_packets > 0) {
 609		pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 610		if (!pkt) {
 611			pkt_shrink_pktlist(pd);
 612			return 0;
 613		}
 614		pkt->id = nr_packets;
 615		pkt->pd = pd;
 616		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 617		nr_packets--;
 618	}
 619	return 1;
 620}
 621
 622static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 623{
 624	struct rb_node *n = rb_next(&node->rb_node);
 625	if (!n)
 626		return NULL;
 627	return rb_entry(n, struct pkt_rb_node, rb_node);
 628}
 629
 630static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 631{
 632	rb_erase(&node->rb_node, &pd->bio_queue);
 633	mempool_free(node, pd->rb_pool);
 634	pd->bio_queue_size--;
 635	BUG_ON(pd->bio_queue_size < 0);
 636}
 637
 638/*
 639 * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 640 */
 641static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 642{
 643	struct rb_node *n = pd->bio_queue.rb_node;
 644	struct rb_node *next;
 645	struct pkt_rb_node *tmp;
 646
 647	if (!n) {
 648		BUG_ON(pd->bio_queue_size > 0);
 649		return NULL;
 650	}
 651
 652	for (;;) {
 653		tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 654		if (s <= tmp->bio->bi_iter.bi_sector)
 655			next = n->rb_left;
 656		else
 657			next = n->rb_right;
 658		if (!next)
 659			break;
 660		n = next;
 661	}
 662
 663	if (s > tmp->bio->bi_iter.bi_sector) {
 664		tmp = pkt_rbtree_next(tmp);
 665		if (!tmp)
 666			return NULL;
 667	}
 668	BUG_ON(s > tmp->bio->bi_iter.bi_sector);
 669	return tmp;
 670}
 671
 672/*
 673 * Insert a node into the pd->bio_queue rb tree.
 674 */
 675static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 676{
 677	struct rb_node **p = &pd->bio_queue.rb_node;
 678	struct rb_node *parent = NULL;
 679	sector_t s = node->bio->bi_iter.bi_sector;
 680	struct pkt_rb_node *tmp;
 681
 682	while (*p) {
 683		parent = *p;
 684		tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 685		if (s < tmp->bio->bi_iter.bi_sector)
 686			p = &(*p)->rb_left;
 687		else
 688			p = &(*p)->rb_right;
 689	}
 690	rb_link_node(&node->rb_node, parent, p);
 691	rb_insert_color(&node->rb_node, &pd->bio_queue);
 692	pd->bio_queue_size++;
 693}
 694
 695/*
 696 * Send a packet_command to the underlying block device and
 697 * wait for completion.
 698 */
 699static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 700{
 701	struct request_queue *q = bdev_get_queue(pd->bdev);
 702	struct request *rq;
 703	int ret = 0;
 704
 705	rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 706			     WRITE : READ, __GFP_WAIT);
 707
 708	if (cgc->buflen) {
 709		ret = blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen,
 710				      __GFP_WAIT);
 711		if (ret)
 712			goto out;
 713	}
 714
 715	rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 716	memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 717
 718	rq->timeout = 60*HZ;
 719	rq->cmd_type = REQ_TYPE_BLOCK_PC;
 720	if (cgc->quiet)
 721		rq->cmd_flags |= REQ_QUIET;
 722
 723	blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 724	if (rq->errors)
 725		ret = -EIO;
 726out:
 727	blk_put_request(rq);
 728	return ret;
 729}
 730
 731static const char *sense_key_string(__u8 index)
 732{
 733	static const char * const info[] = {
 734		"No sense", "Recovered error", "Not ready",
 735		"Medium error", "Hardware error", "Illegal request",
 736		"Unit attention", "Data protect", "Blank check",
 737	};
 738
 739	return index < ARRAY_SIZE(info) ? info[index] : "INVALID";
 740}
 741
 742/*
 743 * A generic sense dump / resolve mechanism should be implemented across
 744 * all ATAPI + SCSI devices.
 745 */
 746static void pkt_dump_sense(struct pktcdvd_device *pd,
 747			   struct packet_command *cgc)
 748{
 
 
 
 
 749	struct request_sense *sense = cgc->sense;
 750
 751	if (sense)
 752		pkt_err(pd, "%*ph - sense %02x.%02x.%02x (%s)\n",
 753			CDROM_PACKET_SIZE, cgc->cmd,
 754			sense->sense_key, sense->asc, sense->ascq,
 755			sense_key_string(sense->sense_key));
 756	else
 757		pkt_err(pd, "%*ph - no sense\n", CDROM_PACKET_SIZE, cgc->cmd);
 
 
 
 
 
 
 
 
 
 
 
 758}
 759
 760/*
 761 * flush the drive cache to media
 762 */
 763static int pkt_flush_cache(struct pktcdvd_device *pd)
 764{
 765	struct packet_command cgc;
 766
 767	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 768	cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 769	cgc.quiet = 1;
 770
 771	/*
 772	 * the IMMED bit -- we default to not setting it, although that
 773	 * would allow a much faster close, this is safer
 774	 */
 775#if 0
 776	cgc.cmd[1] = 1 << 1;
 777#endif
 778	return pkt_generic_packet(pd, &cgc);
 779}
 780
 781/*
 782 * speed is given as the normal factor, e.g. 4 for 4x
 783 */
 784static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 785				unsigned write_speed, unsigned read_speed)
 786{
 787	struct packet_command cgc;
 788	struct request_sense sense;
 789	int ret;
 790
 791	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 792	cgc.sense = &sense;
 793	cgc.cmd[0] = GPCMD_SET_SPEED;
 794	cgc.cmd[2] = (read_speed >> 8) & 0xff;
 795	cgc.cmd[3] = read_speed & 0xff;
 796	cgc.cmd[4] = (write_speed >> 8) & 0xff;
 797	cgc.cmd[5] = write_speed & 0xff;
 798
 799	if ((ret = pkt_generic_packet(pd, &cgc)))
 800		pkt_dump_sense(pd, &cgc);
 801
 802	return ret;
 803}
 804
 805/*
 806 * Queue a bio for processing by the low-level CD device. Must be called
 807 * from process context.
 808 */
 809static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 810{
 811	spin_lock(&pd->iosched.lock);
 812	if (bio_data_dir(bio) == READ)
 813		bio_list_add(&pd->iosched.read_queue, bio);
 814	else
 815		bio_list_add(&pd->iosched.write_queue, bio);
 816	spin_unlock(&pd->iosched.lock);
 817
 818	atomic_set(&pd->iosched.attention, 1);
 819	wake_up(&pd->wqueue);
 820}
 821
 822/*
 823 * Process the queued read/write requests. This function handles special
 824 * requirements for CDRW drives:
 825 * - A cache flush command must be inserted before a read request if the
 826 *   previous request was a write.
 827 * - Switching between reading and writing is slow, so don't do it more often
 828 *   than necessary.
 829 * - Optimize for throughput at the expense of latency. This means that streaming
 830 *   writes will never be interrupted by a read, but if the drive has to seek
 831 *   before the next write, switch to reading instead if there are any pending
 832 *   read requests.
 833 * - Set the read speed according to current usage pattern. When only reading
 834 *   from the device, it's best to use the highest possible read speed, but
 835 *   when switching often between reading and writing, it's better to have the
 836 *   same read and write speeds.
 837 */
 838static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 839{
 840
 841	if (atomic_read(&pd->iosched.attention) == 0)
 842		return;
 843	atomic_set(&pd->iosched.attention, 0);
 844
 845	for (;;) {
 846		struct bio *bio;
 847		int reads_queued, writes_queued;
 848
 849		spin_lock(&pd->iosched.lock);
 850		reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 851		writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 852		spin_unlock(&pd->iosched.lock);
 853
 854		if (!reads_queued && !writes_queued)
 855			break;
 856
 857		if (pd->iosched.writing) {
 858			int need_write_seek = 1;
 859			spin_lock(&pd->iosched.lock);
 860			bio = bio_list_peek(&pd->iosched.write_queue);
 861			spin_unlock(&pd->iosched.lock);
 862			if (bio && (bio->bi_iter.bi_sector ==
 863				    pd->iosched.last_write))
 864				need_write_seek = 0;
 865			if (need_write_seek && reads_queued) {
 866				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 867					pkt_dbg(2, pd, "write, waiting\n");
 868					break;
 869				}
 870				pkt_flush_cache(pd);
 871				pd->iosched.writing = 0;
 872			}
 873		} else {
 874			if (!reads_queued && writes_queued) {
 875				if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 876					pkt_dbg(2, pd, "read, waiting\n");
 877					break;
 878				}
 879				pd->iosched.writing = 1;
 880			}
 881		}
 882
 883		spin_lock(&pd->iosched.lock);
 884		if (pd->iosched.writing)
 885			bio = bio_list_pop(&pd->iosched.write_queue);
 886		else
 887			bio = bio_list_pop(&pd->iosched.read_queue);
 888		spin_unlock(&pd->iosched.lock);
 889
 890		if (!bio)
 891			continue;
 892
 893		if (bio_data_dir(bio) == READ)
 894			pd->iosched.successive_reads +=
 895				bio->bi_iter.bi_size >> 10;
 896		else {
 897			pd->iosched.successive_reads = 0;
 898			pd->iosched.last_write = bio_end_sector(bio);
 899		}
 900		if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 901			if (pd->read_speed == pd->write_speed) {
 902				pd->read_speed = MAX_SPEED;
 903				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 904			}
 905		} else {
 906			if (pd->read_speed != pd->write_speed) {
 907				pd->read_speed = pd->write_speed;
 908				pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 909			}
 910		}
 911
 912		atomic_inc(&pd->cdrw.pending_bios);
 913		generic_make_request(bio);
 914	}
 915}
 916
 917/*
 918 * Special care is needed if the underlying block device has a small
 919 * max_phys_segments value.
 920 */
 921static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 922{
 923	if ((pd->settings.size << 9) / CD_FRAMESIZE
 924	    <= queue_max_segments(q)) {
 925		/*
 926		 * The cdrom device can handle one segment/frame
 927		 */
 928		clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 929		return 0;
 930	} else if ((pd->settings.size << 9) / PAGE_SIZE
 931		   <= queue_max_segments(q)) {
 932		/*
 933		 * We can handle this case at the expense of some extra memory
 934		 * copies during write operations
 935		 */
 936		set_bit(PACKET_MERGE_SEGS, &pd->flags);
 937		return 0;
 938	} else {
 939		pkt_err(pd, "cdrom max_phys_segments too small\n");
 940		return -EIO;
 941	}
 942}
 943
 944/*
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 945 * Copy all data for this packet to pkt->pages[], so that
 946 * a) The number of required segments for the write bio is minimized, which
 947 *    is necessary for some scsi controllers.
 948 * b) The data can be used as cache to avoid read requests if we receive a
 949 *    new write request for the same zone.
 950 */
 951static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
 952{
 953	int f, p, offs;
 954
 955	/* Copy all data to pkt->pages[] */
 956	p = 0;
 957	offs = 0;
 958	for (f = 0; f < pkt->frames; f++) {
 959		if (bvec[f].bv_page != pkt->pages[p]) {
 960			void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset;
 961			void *vto = page_address(pkt->pages[p]) + offs;
 962			memcpy(vto, vfrom, CD_FRAMESIZE);
 963			kunmap_atomic(vfrom);
 964			bvec[f].bv_page = pkt->pages[p];
 965			bvec[f].bv_offset = offs;
 966		} else {
 967			BUG_ON(bvec[f].bv_offset != offs);
 968		}
 969		offs += CD_FRAMESIZE;
 970		if (offs >= PAGE_SIZE) {
 971			offs = 0;
 972			p++;
 973		}
 974	}
 975}
 976
 977static void pkt_end_io_read(struct bio *bio, int err)
 978{
 979	struct packet_data *pkt = bio->bi_private;
 980	struct pktcdvd_device *pd = pkt->pd;
 981	BUG_ON(!pd);
 982
 983	pkt_dbg(2, pd, "bio=%p sec0=%llx sec=%llx err=%d\n",
 984		bio, (unsigned long long)pkt->sector,
 985		(unsigned long long)bio->bi_iter.bi_sector, err);
 986
 987	if (err)
 988		atomic_inc(&pkt->io_errors);
 989	if (atomic_dec_and_test(&pkt->io_wait)) {
 990		atomic_inc(&pkt->run_sm);
 991		wake_up(&pd->wqueue);
 992	}
 993	pkt_bio_finished(pd);
 994}
 995
 996static void pkt_end_io_packet_write(struct bio *bio, int err)
 997{
 998	struct packet_data *pkt = bio->bi_private;
 999	struct pktcdvd_device *pd = pkt->pd;
1000	BUG_ON(!pd);
1001
1002	pkt_dbg(2, pd, "id=%d, err=%d\n", pkt->id, err);
1003
1004	pd->stats.pkt_ended++;
1005
1006	pkt_bio_finished(pd);
1007	atomic_dec(&pkt->io_wait);
1008	atomic_inc(&pkt->run_sm);
1009	wake_up(&pd->wqueue);
1010}
1011
1012/*
1013 * Schedule reads for the holes in a packet
1014 */
1015static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1016{
1017	int frames_read = 0;
1018	struct bio *bio;
1019	int f;
1020	char written[PACKET_MAX_SIZE];
1021
1022	BUG_ON(bio_list_empty(&pkt->orig_bios));
1023
1024	atomic_set(&pkt->io_wait, 0);
1025	atomic_set(&pkt->io_errors, 0);
1026
1027	/*
1028	 * Figure out which frames we need to read before we can write.
1029	 */
1030	memset(written, 0, sizeof(written));
1031	spin_lock(&pkt->lock);
1032	bio_list_for_each(bio, &pkt->orig_bios) {
1033		int first_frame = (bio->bi_iter.bi_sector - pkt->sector) /
1034			(CD_FRAMESIZE >> 9);
1035		int num_frames = bio->bi_iter.bi_size / CD_FRAMESIZE;
1036		pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1037		BUG_ON(first_frame < 0);
1038		BUG_ON(first_frame + num_frames > pkt->frames);
1039		for (f = first_frame; f < first_frame + num_frames; f++)
1040			written[f] = 1;
1041	}
1042	spin_unlock(&pkt->lock);
1043
1044	if (pkt->cache_valid) {
1045		pkt_dbg(2, pd, "zone %llx cached\n",
1046			(unsigned long long)pkt->sector);
1047		goto out_account;
1048	}
1049
1050	/*
1051	 * Schedule reads for missing parts of the packet.
1052	 */
1053	for (f = 0; f < pkt->frames; f++) {
 
 
1054		int p, offset;
1055
1056		if (written[f])
1057			continue;
1058
1059		bio = pkt->r_bios[f];
1060		bio_reset(bio);
1061		bio->bi_iter.bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
 
 
1062		bio->bi_bdev = pd->bdev;
1063		bio->bi_end_io = pkt_end_io_read;
1064		bio->bi_private = pkt;
 
 
1065
1066		p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1067		offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1068		pkt_dbg(2, pd, "Adding frame %d, page:%p offs:%d\n",
1069			f, pkt->pages[p], offset);
1070		if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1071			BUG();
1072
1073		atomic_inc(&pkt->io_wait);
1074		bio->bi_rw = READ;
1075		pkt_queue_bio(pd, bio);
1076		frames_read++;
1077	}
1078
1079out_account:
1080	pkt_dbg(2, pd, "need %d frames for zone %llx\n",
1081		frames_read, (unsigned long long)pkt->sector);
1082	pd->stats.pkt_started++;
1083	pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1084}
1085
1086/*
1087 * Find a packet matching zone, or the least recently used packet if
1088 * there is no match.
1089 */
1090static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1091{
1092	struct packet_data *pkt;
1093
1094	list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1095		if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1096			list_del_init(&pkt->list);
1097			if (pkt->sector != zone)
1098				pkt->cache_valid = 0;
1099			return pkt;
1100		}
1101	}
1102	BUG();
1103	return NULL;
1104}
1105
1106static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1107{
1108	if (pkt->cache_valid) {
1109		list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1110	} else {
1111		list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1112	}
1113}
1114
1115/*
1116 * recover a failed write, query for relocation if possible
1117 *
1118 * returns 1 if recovery is possible, or 0 if not
1119 *
1120 */
1121static int pkt_start_recovery(struct packet_data *pkt)
1122{
1123	/*
1124	 * FIXME. We need help from the file system to implement
1125	 * recovery handling.
1126	 */
1127	return 0;
1128#if 0
1129	struct request *rq = pkt->rq;
1130	struct pktcdvd_device *pd = rq->rq_disk->private_data;
1131	struct block_device *pkt_bdev;
1132	struct super_block *sb = NULL;
1133	unsigned long old_block, new_block;
1134	sector_t new_sector;
1135
1136	pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1137	if (pkt_bdev) {
1138		sb = get_super(pkt_bdev);
1139		bdput(pkt_bdev);
1140	}
1141
1142	if (!sb)
1143		return 0;
1144
1145	if (!sb->s_op->relocate_blocks)
1146		goto out;
1147
1148	old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1149	if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1150		goto out;
1151
1152	new_sector = new_block * (CD_FRAMESIZE >> 9);
1153	pkt->sector = new_sector;
1154
1155	bio_reset(pkt->bio);
1156	pkt->bio->bi_bdev = pd->bdev;
1157	pkt->bio->bi_rw = REQ_WRITE;
1158	pkt->bio->bi_iter.bi_sector = new_sector;
1159	pkt->bio->bi_iter.bi_size = pkt->frames * CD_FRAMESIZE;
1160	pkt->bio->bi_vcnt = pkt->frames;
1161
1162	pkt->bio->bi_end_io = pkt_end_io_packet_write;
1163	pkt->bio->bi_private = pkt;
 
1164
1165	drop_super(sb);
1166	return 1;
1167
1168out:
1169	drop_super(sb);
1170	return 0;
1171#endif
1172}
1173
1174static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1175{
1176#if PACKET_DEBUG > 1
1177	static const char *state_name[] = {
1178		"IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1179	};
1180	enum packet_data_state old_state = pkt->state;
1181	pkt_dbg(2, pd, "pkt %2d : s=%6llx %s -> %s\n",
1182		pkt->id, (unsigned long long)pkt->sector,
1183		state_name[old_state], state_name[state]);
1184#endif
1185	pkt->state = state;
1186}
1187
1188/*
1189 * Scan the work queue to see if we can start a new packet.
1190 * returns non-zero if any work was done.
1191 */
1192static int pkt_handle_queue(struct pktcdvd_device *pd)
1193{
1194	struct packet_data *pkt, *p;
1195	struct bio *bio = NULL;
1196	sector_t zone = 0; /* Suppress gcc warning */
1197	struct pkt_rb_node *node, *first_node;
1198	struct rb_node *n;
1199	int wakeup;
1200
 
 
1201	atomic_set(&pd->scan_queue, 0);
1202
1203	if (list_empty(&pd->cdrw.pkt_free_list)) {
1204		pkt_dbg(2, pd, "no pkt\n");
1205		return 0;
1206	}
1207
1208	/*
1209	 * Try to find a zone we are not already working on.
1210	 */
1211	spin_lock(&pd->lock);
1212	first_node = pkt_rbtree_find(pd, pd->current_sector);
1213	if (!first_node) {
1214		n = rb_first(&pd->bio_queue);
1215		if (n)
1216			first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1217	}
1218	node = first_node;
1219	while (node) {
1220		bio = node->bio;
1221		zone = get_zone(bio->bi_iter.bi_sector, pd);
1222		list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1223			if (p->sector == zone) {
1224				bio = NULL;
1225				goto try_next_bio;
1226			}
1227		}
1228		break;
1229try_next_bio:
1230		node = pkt_rbtree_next(node);
1231		if (!node) {
1232			n = rb_first(&pd->bio_queue);
1233			if (n)
1234				node = rb_entry(n, struct pkt_rb_node, rb_node);
1235		}
1236		if (node == first_node)
1237			node = NULL;
1238	}
1239	spin_unlock(&pd->lock);
1240	if (!bio) {
1241		pkt_dbg(2, pd, "no bio\n");
1242		return 0;
1243	}
1244
1245	pkt = pkt_get_packet_data(pd, zone);
1246
1247	pd->current_sector = zone + pd->settings.size;
1248	pkt->sector = zone;
1249	BUG_ON(pkt->frames != pd->settings.size >> 2);
1250	pkt->write_size = 0;
1251
1252	/*
1253	 * Scan work queue for bios in the same zone and link them
1254	 * to this packet.
1255	 */
1256	spin_lock(&pd->lock);
1257	pkt_dbg(2, pd, "looking for zone %llx\n", (unsigned long long)zone);
1258	while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1259		bio = node->bio;
1260		pkt_dbg(2, pd, "found zone=%llx\n", (unsigned long long)
1261			get_zone(bio->bi_iter.bi_sector, pd));
1262		if (get_zone(bio->bi_iter.bi_sector, pd) != zone)
1263			break;
1264		pkt_rbtree_erase(pd, node);
1265		spin_lock(&pkt->lock);
1266		bio_list_add(&pkt->orig_bios, bio);
1267		pkt->write_size += bio->bi_iter.bi_size / CD_FRAMESIZE;
1268		spin_unlock(&pkt->lock);
1269	}
1270	/* check write congestion marks, and if bio_queue_size is
1271	   below, wake up any waiters */
1272	wakeup = (pd->write_congestion_on > 0
1273	 		&& pd->bio_queue_size <= pd->write_congestion_off);
1274	spin_unlock(&pd->lock);
1275	if (wakeup) {
1276		clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1277					BLK_RW_ASYNC);
1278	}
1279
1280	pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1281	pkt_set_state(pkt, PACKET_WAITING_STATE);
1282	atomic_set(&pkt->run_sm, 1);
1283
1284	spin_lock(&pd->cdrw.active_list_lock);
1285	list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1286	spin_unlock(&pd->cdrw.active_list_lock);
1287
1288	return 1;
1289}
1290
1291/*
1292 * Assemble a bio to write one packet and queue the bio for processing
1293 * by the underlying block device.
1294 */
1295static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1296{
 
1297	int f;
 
1298	struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1299
1300	bio_reset(pkt->w_bio);
1301	pkt->w_bio->bi_iter.bi_sector = pkt->sector;
1302	pkt->w_bio->bi_bdev = pd->bdev;
1303	pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1304	pkt->w_bio->bi_private = pkt;
1305
1306	/* XXX: locking? */
1307	for (f = 0; f < pkt->frames; f++) {
1308		bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1309		bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1310		if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1311			BUG();
1312	}
1313	pkt_dbg(2, pd, "vcnt=%d\n", pkt->w_bio->bi_vcnt);
1314
1315	/*
1316	 * Fill-in bvec with data from orig_bios.
1317	 */
 
1318	spin_lock(&pkt->lock);
1319	bio_copy_data(pkt->w_bio, pkt->orig_bios.head);
 
 
 
 
 
 
 
 
1320
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1321	pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1322	spin_unlock(&pkt->lock);
1323
1324	pkt_dbg(2, pd, "Writing %d frames for zone %llx\n",
1325		pkt->write_size, (unsigned long long)pkt->sector);
 
1326
1327	if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1328		pkt_make_local_copy(pkt, bvec);
1329		pkt->cache_valid = 1;
1330	} else {
1331		pkt->cache_valid = 0;
1332	}
1333
1334	/* Start the write request */
 
 
 
 
 
 
 
 
 
 
 
 
 
1335	atomic_set(&pkt->io_wait, 1);
1336	pkt->w_bio->bi_rw = WRITE;
1337	pkt_queue_bio(pd, pkt->w_bio);
1338}
1339
1340static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1341{
1342	struct bio *bio;
1343
1344	if (!uptodate)
1345		pkt->cache_valid = 0;
1346
1347	/* Finish all bios corresponding to this packet */
1348	while ((bio = bio_list_pop(&pkt->orig_bios)))
1349		bio_endio(bio, uptodate ? 0 : -EIO);
1350}
1351
1352static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1353{
1354	int uptodate;
1355
1356	pkt_dbg(2, pd, "pkt %d\n", pkt->id);
1357
1358	for (;;) {
1359		switch (pkt->state) {
1360		case PACKET_WAITING_STATE:
1361			if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1362				return;
1363
1364			pkt->sleep_time = 0;
1365			pkt_gather_data(pd, pkt);
1366			pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1367			break;
1368
1369		case PACKET_READ_WAIT_STATE:
1370			if (atomic_read(&pkt->io_wait) > 0)
1371				return;
1372
1373			if (atomic_read(&pkt->io_errors) > 0) {
1374				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1375			} else {
1376				pkt_start_write(pd, pkt);
1377			}
1378			break;
1379
1380		case PACKET_WRITE_WAIT_STATE:
1381			if (atomic_read(&pkt->io_wait) > 0)
1382				return;
1383
1384			if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1385				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1386			} else {
1387				pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1388			}
1389			break;
1390
1391		case PACKET_RECOVERY_STATE:
1392			if (pkt_start_recovery(pkt)) {
1393				pkt_start_write(pd, pkt);
1394			} else {
1395				pkt_dbg(2, pd, "No recovery possible\n");
1396				pkt_set_state(pkt, PACKET_FINISHED_STATE);
1397			}
1398			break;
1399
1400		case PACKET_FINISHED_STATE:
1401			uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1402			pkt_finish_packet(pkt, uptodate);
1403			return;
1404
1405		default:
1406			BUG();
1407			break;
1408		}
1409	}
1410}
1411
1412static void pkt_handle_packets(struct pktcdvd_device *pd)
1413{
1414	struct packet_data *pkt, *next;
1415
 
 
1416	/*
1417	 * Run state machine for active packets
1418	 */
1419	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1420		if (atomic_read(&pkt->run_sm) > 0) {
1421			atomic_set(&pkt->run_sm, 0);
1422			pkt_run_state_machine(pd, pkt);
1423		}
1424	}
1425
1426	/*
1427	 * Move no longer active packets to the free list
1428	 */
1429	spin_lock(&pd->cdrw.active_list_lock);
1430	list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1431		if (pkt->state == PACKET_FINISHED_STATE) {
1432			list_del(&pkt->list);
1433			pkt_put_packet_data(pd, pkt);
1434			pkt_set_state(pkt, PACKET_IDLE_STATE);
1435			atomic_set(&pd->scan_queue, 1);
1436		}
1437	}
1438	spin_unlock(&pd->cdrw.active_list_lock);
1439}
1440
1441static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1442{
1443	struct packet_data *pkt;
1444	int i;
1445
1446	for (i = 0; i < PACKET_NUM_STATES; i++)
1447		states[i] = 0;
1448
1449	spin_lock(&pd->cdrw.active_list_lock);
1450	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1451		states[pkt->state]++;
1452	}
1453	spin_unlock(&pd->cdrw.active_list_lock);
1454}
1455
1456/*
1457 * kcdrwd is woken up when writes have been queued for one of our
1458 * registered devices
1459 */
1460static int kcdrwd(void *foobar)
1461{
1462	struct pktcdvd_device *pd = foobar;
1463	struct packet_data *pkt;
1464	long min_sleep_time, residue;
1465
1466	set_user_nice(current, -20);
1467	set_freezable();
1468
1469	for (;;) {
1470		DECLARE_WAITQUEUE(wait, current);
1471
1472		/*
1473		 * Wait until there is something to do
1474		 */
1475		add_wait_queue(&pd->wqueue, &wait);
1476		for (;;) {
1477			set_current_state(TASK_INTERRUPTIBLE);
1478
1479			/* Check if we need to run pkt_handle_queue */
1480			if (atomic_read(&pd->scan_queue) > 0)
1481				goto work_to_do;
1482
1483			/* Check if we need to run the state machine for some packet */
1484			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1485				if (atomic_read(&pkt->run_sm) > 0)
1486					goto work_to_do;
1487			}
1488
1489			/* Check if we need to process the iosched queues */
1490			if (atomic_read(&pd->iosched.attention) != 0)
1491				goto work_to_do;
1492
1493			/* Otherwise, go to sleep */
1494			if (PACKET_DEBUG > 1) {
1495				int states[PACKET_NUM_STATES];
1496				pkt_count_states(pd, states);
1497				pkt_dbg(2, pd, "i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1498					states[0], states[1], states[2],
1499					states[3], states[4], states[5]);
1500			}
1501
1502			min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1503			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1504				if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1505					min_sleep_time = pkt->sleep_time;
1506			}
1507
1508			pkt_dbg(2, pd, "sleeping\n");
1509			residue = schedule_timeout(min_sleep_time);
1510			pkt_dbg(2, pd, "wake up\n");
1511
1512			/* make swsusp happy with our thread */
1513			try_to_freeze();
1514
1515			list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1516				if (!pkt->sleep_time)
1517					continue;
1518				pkt->sleep_time -= min_sleep_time - residue;
1519				if (pkt->sleep_time <= 0) {
1520					pkt->sleep_time = 0;
1521					atomic_inc(&pkt->run_sm);
1522				}
1523			}
1524
1525			if (kthread_should_stop())
1526				break;
1527		}
1528work_to_do:
1529		set_current_state(TASK_RUNNING);
1530		remove_wait_queue(&pd->wqueue, &wait);
1531
1532		if (kthread_should_stop())
1533			break;
1534
1535		/*
1536		 * if pkt_handle_queue returns true, we can queue
1537		 * another request.
1538		 */
1539		while (pkt_handle_queue(pd))
1540			;
1541
1542		/*
1543		 * Handle packet state machine
1544		 */
1545		pkt_handle_packets(pd);
1546
1547		/*
1548		 * Handle iosched queues
1549		 */
1550		pkt_iosched_process_queue(pd);
1551	}
1552
1553	return 0;
1554}
1555
1556static void pkt_print_settings(struct pktcdvd_device *pd)
1557{
1558	pkt_info(pd, "%s packets, %u blocks, Mode-%c disc\n",
1559		 pd->settings.fp ? "Fixed" : "Variable",
1560		 pd->settings.size >> 2,
1561		 pd->settings.block_mode == 8 ? '1' : '2');
1562}
1563
1564static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1565{
1566	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1567
1568	cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1569	cgc->cmd[2] = page_code | (page_control << 6);
1570	cgc->cmd[7] = cgc->buflen >> 8;
1571	cgc->cmd[8] = cgc->buflen & 0xff;
1572	cgc->data_direction = CGC_DATA_READ;
1573	return pkt_generic_packet(pd, cgc);
1574}
1575
1576static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1577{
1578	memset(cgc->cmd, 0, sizeof(cgc->cmd));
1579	memset(cgc->buffer, 0, 2);
1580	cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1581	cgc->cmd[1] = 0x10;		/* PF */
1582	cgc->cmd[7] = cgc->buflen >> 8;
1583	cgc->cmd[8] = cgc->buflen & 0xff;
1584	cgc->data_direction = CGC_DATA_WRITE;
1585	return pkt_generic_packet(pd, cgc);
1586}
1587
1588static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1589{
1590	struct packet_command cgc;
1591	int ret;
1592
1593	/* set up command and get the disc info */
1594	init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1595	cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1596	cgc.cmd[8] = cgc.buflen = 2;
1597	cgc.quiet = 1;
1598
1599	if ((ret = pkt_generic_packet(pd, &cgc)))
1600		return ret;
1601
1602	/* not all drives have the same disc_info length, so requeue
1603	 * packet with the length the drive tells us it can supply
1604	 */
1605	cgc.buflen = be16_to_cpu(di->disc_information_length) +
1606		     sizeof(di->disc_information_length);
1607
1608	if (cgc.buflen > sizeof(disc_information))
1609		cgc.buflen = sizeof(disc_information);
1610
1611	cgc.cmd[8] = cgc.buflen;
1612	return pkt_generic_packet(pd, &cgc);
1613}
1614
1615static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1616{
1617	struct packet_command cgc;
1618	int ret;
1619
1620	init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1621	cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1622	cgc.cmd[1] = type & 3;
1623	cgc.cmd[4] = (track & 0xff00) >> 8;
1624	cgc.cmd[5] = track & 0xff;
1625	cgc.cmd[8] = 8;
1626	cgc.quiet = 1;
1627
1628	if ((ret = pkt_generic_packet(pd, &cgc)))
1629		return ret;
1630
1631	cgc.buflen = be16_to_cpu(ti->track_information_length) +
1632		     sizeof(ti->track_information_length);
1633
1634	if (cgc.buflen > sizeof(track_information))
1635		cgc.buflen = sizeof(track_information);
1636
1637	cgc.cmd[8] = cgc.buflen;
1638	return pkt_generic_packet(pd, &cgc);
1639}
1640
1641static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1642						long *last_written)
1643{
1644	disc_information di;
1645	track_information ti;
1646	__u32 last_track;
1647	int ret = -1;
1648
1649	if ((ret = pkt_get_disc_info(pd, &di)))
1650		return ret;
1651
1652	last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1653	if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1654		return ret;
1655
1656	/* if this track is blank, try the previous. */
1657	if (ti.blank) {
1658		last_track--;
1659		if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1660			return ret;
1661	}
1662
1663	/* if last recorded field is valid, return it. */
1664	if (ti.lra_v) {
1665		*last_written = be32_to_cpu(ti.last_rec_address);
1666	} else {
1667		/* make it up instead */
1668		*last_written = be32_to_cpu(ti.track_start) +
1669				be32_to_cpu(ti.track_size);
1670		if (ti.free_blocks)
1671			*last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1672	}
1673	return 0;
1674}
1675
1676/*
1677 * write mode select package based on pd->settings
1678 */
1679static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1680{
1681	struct packet_command cgc;
1682	struct request_sense sense;
1683	write_param_page *wp;
1684	char buffer[128];
1685	int ret, size;
1686
1687	/* doesn't apply to DVD+RW or DVD-RAM */
1688	if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1689		return 0;
1690
1691	memset(buffer, 0, sizeof(buffer));
1692	init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1693	cgc.sense = &sense;
1694	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1695		pkt_dump_sense(pd, &cgc);
1696		return ret;
1697	}
1698
1699	size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1700	pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1701	if (size > sizeof(buffer))
1702		size = sizeof(buffer);
1703
1704	/*
1705	 * now get it all
1706	 */
1707	init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1708	cgc.sense = &sense;
1709	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1710		pkt_dump_sense(pd, &cgc);
1711		return ret;
1712	}
1713
1714	/*
1715	 * write page is offset header + block descriptor length
1716	 */
1717	wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1718
1719	wp->fp = pd->settings.fp;
1720	wp->track_mode = pd->settings.track_mode;
1721	wp->write_type = pd->settings.write_type;
1722	wp->data_block_type = pd->settings.block_mode;
1723
1724	wp->multi_session = 0;
1725
1726#ifdef PACKET_USE_LS
1727	wp->link_size = 7;
1728	wp->ls_v = 1;
1729#endif
1730
1731	if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1732		wp->session_format = 0;
1733		wp->subhdr2 = 0x20;
1734	} else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1735		wp->session_format = 0x20;
1736		wp->subhdr2 = 8;
1737#if 0
1738		wp->mcn[0] = 0x80;
1739		memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1740#endif
1741	} else {
1742		/*
1743		 * paranoia
1744		 */
1745		pkt_err(pd, "write mode wrong %d\n", wp->data_block_type);
1746		return 1;
1747	}
1748	wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1749
1750	cgc.buflen = cgc.cmd[8] = size;
1751	if ((ret = pkt_mode_select(pd, &cgc))) {
1752		pkt_dump_sense(pd, &cgc);
1753		return ret;
1754	}
1755
1756	pkt_print_settings(pd);
1757	return 0;
1758}
1759
1760/*
1761 * 1 -- we can write to this track, 0 -- we can't
1762 */
1763static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1764{
1765	switch (pd->mmc3_profile) {
1766		case 0x1a: /* DVD+RW */
1767		case 0x12: /* DVD-RAM */
1768			/* The track is always writable on DVD+RW/DVD-RAM */
1769			return 1;
1770		default:
1771			break;
1772	}
1773
1774	if (!ti->packet || !ti->fp)
1775		return 0;
1776
1777	/*
1778	 * "good" settings as per Mt Fuji.
1779	 */
1780	if (ti->rt == 0 && ti->blank == 0)
1781		return 1;
1782
1783	if (ti->rt == 0 && ti->blank == 1)
1784		return 1;
1785
1786	if (ti->rt == 1 && ti->blank == 0)
1787		return 1;
1788
1789	pkt_err(pd, "bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1790	return 0;
1791}
1792
1793/*
1794 * 1 -- we can write to this disc, 0 -- we can't
1795 */
1796static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1797{
1798	switch (pd->mmc3_profile) {
1799		case 0x0a: /* CD-RW */
1800		case 0xffff: /* MMC3 not supported */
1801			break;
1802		case 0x1a: /* DVD+RW */
1803		case 0x13: /* DVD-RW */
1804		case 0x12: /* DVD-RAM */
1805			return 1;
1806		default:
1807			pkt_dbg(2, pd, "Wrong disc profile (%x)\n",
1808				pd->mmc3_profile);
1809			return 0;
1810	}
1811
1812	/*
1813	 * for disc type 0xff we should probably reserve a new track.
1814	 * but i'm not sure, should we leave this to user apps? probably.
1815	 */
1816	if (di->disc_type == 0xff) {
1817		pkt_notice(pd, "unknown disc - no track?\n");
1818		return 0;
1819	}
1820
1821	if (di->disc_type != 0x20 && di->disc_type != 0) {
1822		pkt_err(pd, "wrong disc type (%x)\n", di->disc_type);
1823		return 0;
1824	}
1825
1826	if (di->erasable == 0) {
1827		pkt_notice(pd, "disc not erasable\n");
1828		return 0;
1829	}
1830
1831	if (di->border_status == PACKET_SESSION_RESERVED) {
1832		pkt_err(pd, "can't write to last track (reserved)\n");
1833		return 0;
1834	}
1835
1836	return 1;
1837}
1838
1839static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1840{
1841	struct packet_command cgc;
1842	unsigned char buf[12];
1843	disc_information di;
1844	track_information ti;
1845	int ret, track;
1846
1847	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1848	cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1849	cgc.cmd[8] = 8;
1850	ret = pkt_generic_packet(pd, &cgc);
1851	pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1852
1853	memset(&di, 0, sizeof(disc_information));
1854	memset(&ti, 0, sizeof(track_information));
1855
1856	if ((ret = pkt_get_disc_info(pd, &di))) {
1857		pkt_err(pd, "failed get_disc\n");
1858		return ret;
1859	}
1860
1861	if (!pkt_writable_disc(pd, &di))
1862		return -EROFS;
1863
1864	pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1865
1866	track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1867	if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1868		pkt_err(pd, "failed get_track\n");
1869		return ret;
1870	}
1871
1872	if (!pkt_writable_track(pd, &ti)) {
1873		pkt_err(pd, "can't write to this track\n");
1874		return -EROFS;
1875	}
1876
1877	/*
1878	 * we keep packet size in 512 byte units, makes it easier to
1879	 * deal with request calculations.
1880	 */
1881	pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1882	if (pd->settings.size == 0) {
1883		pkt_notice(pd, "detected zero packet size!\n");
1884		return -ENXIO;
1885	}
1886	if (pd->settings.size > PACKET_MAX_SECTORS) {
1887		pkt_err(pd, "packet size is too big\n");
1888		return -EROFS;
1889	}
1890	pd->settings.fp = ti.fp;
1891	pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1892
1893	if (ti.nwa_v) {
1894		pd->nwa = be32_to_cpu(ti.next_writable);
1895		set_bit(PACKET_NWA_VALID, &pd->flags);
1896	}
1897
1898	/*
1899	 * in theory we could use lra on -RW media as well and just zero
1900	 * blocks that haven't been written yet, but in practice that
1901	 * is just a no-go. we'll use that for -R, naturally.
1902	 */
1903	if (ti.lra_v) {
1904		pd->lra = be32_to_cpu(ti.last_rec_address);
1905		set_bit(PACKET_LRA_VALID, &pd->flags);
1906	} else {
1907		pd->lra = 0xffffffff;
1908		set_bit(PACKET_LRA_VALID, &pd->flags);
1909	}
1910
1911	/*
1912	 * fine for now
1913	 */
1914	pd->settings.link_loss = 7;
1915	pd->settings.write_type = 0;	/* packet */
1916	pd->settings.track_mode = ti.track_mode;
1917
1918	/*
1919	 * mode1 or mode2 disc
1920	 */
1921	switch (ti.data_mode) {
1922		case PACKET_MODE1:
1923			pd->settings.block_mode = PACKET_BLOCK_MODE1;
1924			break;
1925		case PACKET_MODE2:
1926			pd->settings.block_mode = PACKET_BLOCK_MODE2;
1927			break;
1928		default:
1929			pkt_err(pd, "unknown data mode\n");
1930			return -EROFS;
1931	}
1932	return 0;
1933}
1934
1935/*
1936 * enable/disable write caching on drive
1937 */
1938static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
1939						int set)
1940{
1941	struct packet_command cgc;
1942	struct request_sense sense;
1943	unsigned char buf[64];
1944	int ret;
1945
1946	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1947	cgc.sense = &sense;
1948	cgc.buflen = pd->mode_offset + 12;
1949
1950	/*
1951	 * caching mode page might not be there, so quiet this command
1952	 */
1953	cgc.quiet = 1;
1954
1955	if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1956		return ret;
1957
1958	buf[pd->mode_offset + 10] |= (!!set << 2);
1959
1960	cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1961	ret = pkt_mode_select(pd, &cgc);
1962	if (ret) {
1963		pkt_err(pd, "write caching control failed\n");
1964		pkt_dump_sense(pd, &cgc);
1965	} else if (!ret && set)
1966		pkt_notice(pd, "enabled write caching\n");
1967	return ret;
1968}
1969
1970static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1971{
1972	struct packet_command cgc;
1973
1974	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1975	cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1976	cgc.cmd[4] = lockflag ? 1 : 0;
1977	return pkt_generic_packet(pd, &cgc);
1978}
1979
1980/*
1981 * Returns drive maximum write speed
1982 */
1983static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1984						unsigned *write_speed)
1985{
1986	struct packet_command cgc;
1987	struct request_sense sense;
1988	unsigned char buf[256+18];
1989	unsigned char *cap_buf;
1990	int ret, offset;
1991
1992	cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
1993	init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
1994	cgc.sense = &sense;
1995
1996	ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
1997	if (ret) {
1998		cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
1999			     sizeof(struct mode_page_header);
2000		ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2001		if (ret) {
2002			pkt_dump_sense(pd, &cgc);
2003			return ret;
2004		}
2005	}
2006
2007	offset = 20;			    /* Obsoleted field, used by older drives */
2008	if (cap_buf[1] >= 28)
2009		offset = 28;		    /* Current write speed selected */
2010	if (cap_buf[1] >= 30) {
2011		/* If the drive reports at least one "Logical Unit Write
2012		 * Speed Performance Descriptor Block", use the information
2013		 * in the first block. (contains the highest speed)
2014		 */
2015		int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2016		if (num_spdb > 0)
2017			offset = 34;
2018	}
2019
2020	*write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2021	return 0;
2022}
2023
2024/* These tables from cdrecord - I don't have orange book */
2025/* standard speed CD-RW (1-4x) */
2026static char clv_to_speed[16] = {
2027	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2028	   0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2029};
2030/* high speed CD-RW (-10x) */
2031static char hs_clv_to_speed[16] = {
2032	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2033	   0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2034};
2035/* ultra high speed CD-RW */
2036static char us_clv_to_speed[16] = {
2037	/* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2038	   0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2039};
2040
2041/*
2042 * reads the maximum media speed from ATIP
2043 */
2044static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2045						unsigned *speed)
2046{
2047	struct packet_command cgc;
2048	struct request_sense sense;
2049	unsigned char buf[64];
2050	unsigned int size, st, sp;
2051	int ret;
2052
2053	init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2054	cgc.sense = &sense;
2055	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2056	cgc.cmd[1] = 2;
2057	cgc.cmd[2] = 4; /* READ ATIP */
2058	cgc.cmd[8] = 2;
2059	ret = pkt_generic_packet(pd, &cgc);
2060	if (ret) {
2061		pkt_dump_sense(pd, &cgc);
2062		return ret;
2063	}
2064	size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2065	if (size > sizeof(buf))
2066		size = sizeof(buf);
2067
2068	init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2069	cgc.sense = &sense;
2070	cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2071	cgc.cmd[1] = 2;
2072	cgc.cmd[2] = 4;
2073	cgc.cmd[8] = size;
2074	ret = pkt_generic_packet(pd, &cgc);
2075	if (ret) {
2076		pkt_dump_sense(pd, &cgc);
2077		return ret;
2078	}
2079
2080	if (!(buf[6] & 0x40)) {
2081		pkt_notice(pd, "disc type is not CD-RW\n");
2082		return 1;
2083	}
2084	if (!(buf[6] & 0x4)) {
2085		pkt_notice(pd, "A1 values on media are not valid, maybe not CDRW?\n");
2086		return 1;
2087	}
2088
2089	st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2090
2091	sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2092
2093	/* Info from cdrecord */
2094	switch (st) {
2095		case 0: /* standard speed */
2096			*speed = clv_to_speed[sp];
2097			break;
2098		case 1: /* high speed */
2099			*speed = hs_clv_to_speed[sp];
2100			break;
2101		case 2: /* ultra high speed */
2102			*speed = us_clv_to_speed[sp];
2103			break;
2104		default:
2105			pkt_notice(pd, "unknown disc sub-type %d\n", st);
2106			return 1;
2107	}
2108	if (*speed) {
2109		pkt_info(pd, "maximum media speed: %d\n", *speed);
2110		return 0;
2111	} else {
2112		pkt_notice(pd, "unknown speed %d for sub-type %d\n", sp, st);
2113		return 1;
2114	}
2115}
2116
2117static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2118{
2119	struct packet_command cgc;
2120	struct request_sense sense;
2121	int ret;
2122
2123	pkt_dbg(2, pd, "Performing OPC\n");
2124
2125	init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2126	cgc.sense = &sense;
2127	cgc.timeout = 60*HZ;
2128	cgc.cmd[0] = GPCMD_SEND_OPC;
2129	cgc.cmd[1] = 1;
2130	if ((ret = pkt_generic_packet(pd, &cgc)))
2131		pkt_dump_sense(pd, &cgc);
2132	return ret;
2133}
2134
2135static int pkt_open_write(struct pktcdvd_device *pd)
2136{
2137	int ret;
2138	unsigned int write_speed, media_write_speed, read_speed;
2139
2140	if ((ret = pkt_probe_settings(pd))) {
2141		pkt_dbg(2, pd, "failed probe\n");
2142		return ret;
2143	}
2144
2145	if ((ret = pkt_set_write_settings(pd))) {
2146		pkt_dbg(1, pd, "failed saving write settings\n");
2147		return -EIO;
2148	}
2149
2150	pkt_write_caching(pd, USE_WCACHING);
2151
2152	if ((ret = pkt_get_max_speed(pd, &write_speed)))
2153		write_speed = 16 * 177;
2154	switch (pd->mmc3_profile) {
2155		case 0x13: /* DVD-RW */
2156		case 0x1a: /* DVD+RW */
2157		case 0x12: /* DVD-RAM */
2158			pkt_dbg(1, pd, "write speed %ukB/s\n", write_speed);
2159			break;
2160		default:
2161			if ((ret = pkt_media_speed(pd, &media_write_speed)))
2162				media_write_speed = 16;
2163			write_speed = min(write_speed, media_write_speed * 177);
2164			pkt_dbg(1, pd, "write speed %ux\n", write_speed / 176);
2165			break;
2166	}
2167	read_speed = write_speed;
2168
2169	if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2170		pkt_dbg(1, pd, "couldn't set write speed\n");
2171		return -EIO;
2172	}
2173	pd->write_speed = write_speed;
2174	pd->read_speed = read_speed;
2175
2176	if ((ret = pkt_perform_opc(pd))) {
2177		pkt_dbg(1, pd, "Optimum Power Calibration failed\n");
2178	}
2179
2180	return 0;
2181}
2182
2183/*
2184 * called at open time.
2185 */
2186static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2187{
2188	int ret;
2189	long lba;
2190	struct request_queue *q;
2191
2192	/*
2193	 * We need to re-open the cdrom device without O_NONBLOCK to be able
2194	 * to read/write from/to it. It is already opened in O_NONBLOCK mode
2195	 * so bdget() can't fail.
2196	 */
2197	bdget(pd->bdev->bd_dev);
2198	if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2199		goto out;
2200
2201	if ((ret = pkt_get_last_written(pd, &lba))) {
2202		pkt_err(pd, "pkt_get_last_written failed\n");
2203		goto out_putdev;
2204	}
2205
2206	set_capacity(pd->disk, lba << 2);
2207	set_capacity(pd->bdev->bd_disk, lba << 2);
2208	bd_set_size(pd->bdev, (loff_t)lba << 11);
2209
2210	q = bdev_get_queue(pd->bdev);
2211	if (write) {
2212		if ((ret = pkt_open_write(pd)))
2213			goto out_putdev;
2214		/*
2215		 * Some CDRW drives can not handle writes larger than one packet,
2216		 * even if the size is a multiple of the packet size.
2217		 */
2218		spin_lock_irq(q->queue_lock);
2219		blk_queue_max_hw_sectors(q, pd->settings.size);
2220		spin_unlock_irq(q->queue_lock);
2221		set_bit(PACKET_WRITABLE, &pd->flags);
2222	} else {
2223		pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2224		clear_bit(PACKET_WRITABLE, &pd->flags);
2225	}
2226
2227	if ((ret = pkt_set_segment_merging(pd, q)))
2228		goto out_putdev;
2229
2230	if (write) {
2231		if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2232			pkt_err(pd, "not enough memory for buffers\n");
2233			ret = -ENOMEM;
2234			goto out_putdev;
2235		}
2236		pkt_info(pd, "%lukB available on disc\n", lba << 1);
2237	}
2238
2239	return 0;
2240
2241out_putdev:
2242	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2243out:
2244	return ret;
2245}
2246
2247/*
2248 * called when the device is closed. makes sure that the device flushes
2249 * the internal cache before we close.
2250 */
2251static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2252{
2253	if (flush && pkt_flush_cache(pd))
2254		pkt_dbg(1, pd, "not flushing cache\n");
2255
2256	pkt_lock_door(pd, 0);
2257
2258	pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2259	blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2260
2261	pkt_shrink_pktlist(pd);
2262}
2263
2264static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2265{
2266	if (dev_minor >= MAX_WRITERS)
2267		return NULL;
2268	return pkt_devs[dev_minor];
2269}
2270
2271static int pkt_open(struct block_device *bdev, fmode_t mode)
2272{
2273	struct pktcdvd_device *pd = NULL;
2274	int ret;
2275
 
 
2276	mutex_lock(&pktcdvd_mutex);
2277	mutex_lock(&ctl_mutex);
2278	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2279	if (!pd) {
2280		ret = -ENODEV;
2281		goto out;
2282	}
2283	BUG_ON(pd->refcnt < 0);
2284
2285	pd->refcnt++;
2286	if (pd->refcnt > 1) {
2287		if ((mode & FMODE_WRITE) &&
2288		    !test_bit(PACKET_WRITABLE, &pd->flags)) {
2289			ret = -EBUSY;
2290			goto out_dec;
2291		}
2292	} else {
2293		ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2294		if (ret)
2295			goto out_dec;
2296		/*
2297		 * needed here as well, since ext2 (among others) may change
2298		 * the blocksize at mount time
2299		 */
2300		set_blocksize(bdev, CD_FRAMESIZE);
2301	}
2302
2303	mutex_unlock(&ctl_mutex);
2304	mutex_unlock(&pktcdvd_mutex);
2305	return 0;
2306
2307out_dec:
2308	pd->refcnt--;
2309out:
 
2310	mutex_unlock(&ctl_mutex);
2311	mutex_unlock(&pktcdvd_mutex);
2312	return ret;
2313}
2314
2315static void pkt_close(struct gendisk *disk, fmode_t mode)
2316{
2317	struct pktcdvd_device *pd = disk->private_data;
 
2318
2319	mutex_lock(&pktcdvd_mutex);
2320	mutex_lock(&ctl_mutex);
2321	pd->refcnt--;
2322	BUG_ON(pd->refcnt < 0);
2323	if (pd->refcnt == 0) {
2324		int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2325		pkt_release_dev(pd, flush);
2326	}
2327	mutex_unlock(&ctl_mutex);
2328	mutex_unlock(&pktcdvd_mutex);
 
2329}
2330
2331
2332static void pkt_end_io_read_cloned(struct bio *bio, int err)
2333{
2334	struct packet_stacked_data *psd = bio->bi_private;
2335	struct pktcdvd_device *pd = psd->pd;
2336
2337	bio_put(bio);
2338	bio_endio(psd->bio, err);
2339	mempool_free(psd, psd_pool);
2340	pkt_bio_finished(pd);
2341}
2342
2343static void pkt_make_request_read(struct pktcdvd_device *pd, struct bio *bio)
2344{
2345	struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2346	struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2347
2348	psd->pd = pd;
2349	psd->bio = bio;
2350	cloned_bio->bi_bdev = pd->bdev;
2351	cloned_bio->bi_private = psd;
2352	cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2353	pd->stats.secs_r += bio_sectors(bio);
2354	pkt_queue_bio(pd, cloned_bio);
2355}
2356
2357static void pkt_make_request_write(struct request_queue *q, struct bio *bio)
2358{
2359	struct pktcdvd_device *pd = q->queuedata;
2360	sector_t zone;
2361	struct packet_data *pkt;
2362	int was_empty, blocked_bio;
2363	struct pkt_rb_node *node;
2364
2365	zone = get_zone(bio->bi_iter.bi_sector, pd);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2366
2367	/*
2368	 * If we find a matching packet in state WAITING or READ_WAIT, we can
2369	 * just append this bio to that packet.
2370	 */
2371	spin_lock(&pd->cdrw.active_list_lock);
2372	blocked_bio = 0;
2373	list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2374		if (pkt->sector == zone) {
2375			spin_lock(&pkt->lock);
2376			if ((pkt->state == PACKET_WAITING_STATE) ||
2377			    (pkt->state == PACKET_READ_WAIT_STATE)) {
2378				bio_list_add(&pkt->orig_bios, bio);
2379				pkt->write_size +=
2380					bio->bi_iter.bi_size / CD_FRAMESIZE;
2381				if ((pkt->write_size >= pkt->frames) &&
2382				    (pkt->state == PACKET_WAITING_STATE)) {
2383					atomic_inc(&pkt->run_sm);
2384					wake_up(&pd->wqueue);
2385				}
2386				spin_unlock(&pkt->lock);
2387				spin_unlock(&pd->cdrw.active_list_lock);
2388				return;
2389			} else {
2390				blocked_bio = 1;
2391			}
2392			spin_unlock(&pkt->lock);
2393		}
2394	}
2395	spin_unlock(&pd->cdrw.active_list_lock);
2396
2397 	/*
2398	 * Test if there is enough room left in the bio work queue
2399	 * (queue size >= congestion on mark).
2400	 * If not, wait till the work queue size is below the congestion off mark.
2401	 */
2402	spin_lock(&pd->lock);
2403	if (pd->write_congestion_on > 0
2404	    && pd->bio_queue_size >= pd->write_congestion_on) {
2405		set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2406		do {
2407			spin_unlock(&pd->lock);
2408			congestion_wait(BLK_RW_ASYNC, HZ);
2409			spin_lock(&pd->lock);
2410		} while(pd->bio_queue_size > pd->write_congestion_off);
2411	}
2412	spin_unlock(&pd->lock);
2413
2414	/*
2415	 * No matching packet found. Store the bio in the work queue.
2416	 */
2417	node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2418	node->bio = bio;
2419	spin_lock(&pd->lock);
2420	BUG_ON(pd->bio_queue_size < 0);
2421	was_empty = (pd->bio_queue_size == 0);
2422	pkt_rbtree_insert(pd, node);
2423	spin_unlock(&pd->lock);
2424
2425	/*
2426	 * Wake up the worker thread.
2427	 */
2428	atomic_set(&pd->scan_queue, 1);
2429	if (was_empty) {
2430		/* This wake_up is required for correct operation */
2431		wake_up(&pd->wqueue);
2432	} else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2433		/*
2434		 * This wake up is not required for correct operation,
2435		 * but improves performance in some cases.
2436		 */
2437		wake_up(&pd->wqueue);
2438	}
2439}
2440
2441static void pkt_make_request(struct request_queue *q, struct bio *bio)
2442{
2443	struct pktcdvd_device *pd;
2444	char b[BDEVNAME_SIZE];
2445	struct bio *split;
2446
2447	pd = q->queuedata;
2448	if (!pd) {
2449		pr_err("%s incorrect request queue\n",
2450		       bdevname(bio->bi_bdev, b));
2451		goto end_io;
2452	}
2453
2454	pkt_dbg(2, pd, "start = %6llx stop = %6llx\n",
2455		(unsigned long long)bio->bi_iter.bi_sector,
2456		(unsigned long long)bio_end_sector(bio));
2457
2458	/*
2459	 * Clone READ bios so we can have our own bi_end_io callback.
2460	 */
2461	if (bio_data_dir(bio) == READ) {
2462		pkt_make_request_read(pd, bio);
2463		return;
2464	}
2465
2466	if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2467		pkt_notice(pd, "WRITE for ro device (%llu)\n",
2468			   (unsigned long long)bio->bi_iter.bi_sector);
2469		goto end_io;
2470	}
2471
2472	if (!bio->bi_iter.bi_size || (bio->bi_iter.bi_size % CD_FRAMESIZE)) {
2473		pkt_err(pd, "wrong bio size\n");
2474		goto end_io;
2475	}
2476
2477	blk_queue_bounce(q, &bio);
2478
2479	do {
2480		sector_t zone = get_zone(bio->bi_iter.bi_sector, pd);
2481		sector_t last_zone = get_zone(bio_end_sector(bio) - 1, pd);
2482
2483		if (last_zone != zone) {
2484			BUG_ON(last_zone != zone + pd->settings.size);
2485
2486			split = bio_split(bio, last_zone -
2487					  bio->bi_iter.bi_sector,
2488					  GFP_NOIO, fs_bio_set);
2489			bio_chain(split, bio);
2490		} else {
2491			split = bio;
2492		}
2493
2494		pkt_make_request_write(q, split);
2495	} while (split != bio);
2496
2497	return;
2498end_io:
2499	bio_io_error(bio);
 
2500}
2501
2502
2503
2504static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2505			  struct bio_vec *bvec)
2506{
2507	struct pktcdvd_device *pd = q->queuedata;
2508	sector_t zone = get_zone(bmd->bi_sector, pd);
2509	int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2510	int remaining = (pd->settings.size << 9) - used;
2511	int remaining2;
2512
2513	/*
2514	 * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2515	 * boundary, pkt_make_request() will split the bio.
2516	 */
2517	remaining2 = PAGE_SIZE - bmd->bi_size;
2518	remaining = max(remaining, remaining2);
2519
2520	BUG_ON(remaining < 0);
2521	return remaining;
2522}
2523
2524static void pkt_init_queue(struct pktcdvd_device *pd)
2525{
2526	struct request_queue *q = pd->disk->queue;
2527
2528	blk_queue_make_request(q, pkt_make_request);
2529	blk_queue_logical_block_size(q, CD_FRAMESIZE);
2530	blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2531	blk_queue_merge_bvec(q, pkt_merge_bvec);
2532	q->queuedata = pd;
2533}
2534
2535static int pkt_seq_show(struct seq_file *m, void *p)
2536{
2537	struct pktcdvd_device *pd = m->private;
2538	char *msg;
2539	char bdev_buf[BDEVNAME_SIZE];
2540	int states[PACKET_NUM_STATES];
2541
2542	seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2543		   bdevname(pd->bdev, bdev_buf));
2544
2545	seq_printf(m, "\nSettings:\n");
2546	seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2547
2548	if (pd->settings.write_type == 0)
2549		msg = "Packet";
2550	else
2551		msg = "Unknown";
2552	seq_printf(m, "\twrite type:\t\t%s\n", msg);
2553
2554	seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2555	seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2556
2557	seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2558
2559	if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2560		msg = "Mode 1";
2561	else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2562		msg = "Mode 2";
2563	else
2564		msg = "Unknown";
2565	seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2566
2567	seq_printf(m, "\nStatistics:\n");
2568	seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2569	seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2570	seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2571	seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2572	seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2573
2574	seq_printf(m, "\nMisc:\n");
2575	seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2576	seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2577	seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2578	seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2579	seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2580	seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2581
2582	seq_printf(m, "\nQueue state:\n");
2583	seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2584	seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2585	seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2586
2587	pkt_count_states(pd, states);
2588	seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2589		   states[0], states[1], states[2], states[3], states[4], states[5]);
2590
2591	seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2592			pd->write_congestion_off,
2593			pd->write_congestion_on);
2594	return 0;
2595}
2596
2597static int pkt_seq_open(struct inode *inode, struct file *file)
2598{
2599	return single_open(file, pkt_seq_show, PDE_DATA(inode));
2600}
2601
2602static const struct file_operations pkt_proc_fops = {
2603	.open	= pkt_seq_open,
2604	.read	= seq_read,
2605	.llseek	= seq_lseek,
2606	.release = single_release
2607};
2608
2609static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2610{
2611	int i;
2612	int ret = 0;
2613	char b[BDEVNAME_SIZE];
2614	struct block_device *bdev;
2615
2616	if (pd->pkt_dev == dev) {
2617		pkt_err(pd, "recursive setup not allowed\n");
2618		return -EBUSY;
2619	}
2620	for (i = 0; i < MAX_WRITERS; i++) {
2621		struct pktcdvd_device *pd2 = pkt_devs[i];
2622		if (!pd2)
2623			continue;
2624		if (pd2->bdev->bd_dev == dev) {
2625			pkt_err(pd, "%s already setup\n",
2626				bdevname(pd2->bdev, b));
2627			return -EBUSY;
2628		}
2629		if (pd2->pkt_dev == dev) {
2630			pkt_err(pd, "can't chain pktcdvd devices\n");
2631			return -EBUSY;
2632		}
2633	}
2634
2635	bdev = bdget(dev);
2636	if (!bdev)
2637		return -ENOMEM;
2638	ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2639	if (ret)
2640		return ret;
2641
2642	/* This is safe, since we have a reference from open(). */
2643	__module_get(THIS_MODULE);
2644
2645	pd->bdev = bdev;
2646	set_blocksize(bdev, CD_FRAMESIZE);
2647
2648	pkt_init_queue(pd);
2649
2650	atomic_set(&pd->cdrw.pending_bios, 0);
2651	pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2652	if (IS_ERR(pd->cdrw.thread)) {
2653		pkt_err(pd, "can't start kernel thread\n");
2654		ret = -ENOMEM;
2655		goto out_mem;
2656	}
2657
2658	proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2659	pkt_dbg(1, pd, "writer mapped to %s\n", bdevname(bdev, b));
2660	return 0;
2661
2662out_mem:
2663	blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2664	/* This is safe: open() is still holding a reference. */
2665	module_put(THIS_MODULE);
2666	return ret;
2667}
2668
2669static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2670{
2671	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2672	int ret;
2673
2674	pkt_dbg(2, pd, "cmd %x, dev %d:%d\n",
2675		cmd, MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2676
2677	mutex_lock(&pktcdvd_mutex);
2678	switch (cmd) {
2679	case CDROMEJECT:
2680		/*
2681		 * The door gets locked when the device is opened, so we
2682		 * have to unlock it or else the eject command fails.
2683		 */
2684		if (pd->refcnt == 1)
2685			pkt_lock_door(pd, 0);
2686		/* fallthru */
2687	/*
2688	 * forward selected CDROM ioctls to CD-ROM, for UDF
2689	 */
2690	case CDROMMULTISESSION:
2691	case CDROMREADTOCENTRY:
2692	case CDROM_LAST_WRITTEN:
2693	case CDROM_SEND_PACKET:
2694	case SCSI_IOCTL_SEND_COMMAND:
2695		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2696		break;
2697
2698	default:
2699		pkt_dbg(2, pd, "Unknown ioctl (%x)\n", cmd);
2700		ret = -ENOTTY;
2701	}
2702	mutex_unlock(&pktcdvd_mutex);
2703
2704	return ret;
2705}
2706
2707static unsigned int pkt_check_events(struct gendisk *disk,
2708				     unsigned int clearing)
2709{
2710	struct pktcdvd_device *pd = disk->private_data;
2711	struct gendisk *attached_disk;
2712
2713	if (!pd)
2714		return 0;
2715	if (!pd->bdev)
2716		return 0;
2717	attached_disk = pd->bdev->bd_disk;
2718	if (!attached_disk || !attached_disk->fops->check_events)
2719		return 0;
2720	return attached_disk->fops->check_events(attached_disk, clearing);
2721}
2722
2723static const struct block_device_operations pktcdvd_ops = {
2724	.owner =		THIS_MODULE,
2725	.open =			pkt_open,
2726	.release =		pkt_close,
2727	.ioctl =		pkt_ioctl,
2728	.check_events =		pkt_check_events,
2729};
2730
2731static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
2732{
2733	return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2734}
2735
2736/*
2737 * Set up mapping from pktcdvd device to CD-ROM device.
2738 */
2739static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2740{
2741	int idx;
2742	int ret = -ENOMEM;
2743	struct pktcdvd_device *pd;
2744	struct gendisk *disk;
2745
2746	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2747
2748	for (idx = 0; idx < MAX_WRITERS; idx++)
2749		if (!pkt_devs[idx])
2750			break;
2751	if (idx == MAX_WRITERS) {
2752		pr_err("max %d writers supported\n", MAX_WRITERS);
2753		ret = -EBUSY;
2754		goto out_mutex;
2755	}
2756
2757	pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2758	if (!pd)
2759		goto out_mutex;
2760
2761	pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2762						  sizeof(struct pkt_rb_node));
2763	if (!pd->rb_pool)
2764		goto out_mem;
2765
2766	INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2767	INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2768	spin_lock_init(&pd->cdrw.active_list_lock);
2769
2770	spin_lock_init(&pd->lock);
2771	spin_lock_init(&pd->iosched.lock);
2772	bio_list_init(&pd->iosched.read_queue);
2773	bio_list_init(&pd->iosched.write_queue);
2774	sprintf(pd->name, DRIVER_NAME"%d", idx);
2775	init_waitqueue_head(&pd->wqueue);
2776	pd->bio_queue = RB_ROOT;
2777
2778	pd->write_congestion_on  = write_congestion_on;
2779	pd->write_congestion_off = write_congestion_off;
2780
2781	disk = alloc_disk(1);
2782	if (!disk)
2783		goto out_mem;
2784	pd->disk = disk;
2785	disk->major = pktdev_major;
2786	disk->first_minor = idx;
2787	disk->fops = &pktcdvd_ops;
2788	disk->flags = GENHD_FL_REMOVABLE;
2789	strcpy(disk->disk_name, pd->name);
2790	disk->devnode = pktcdvd_devnode;
2791	disk->private_data = pd;
2792	disk->queue = blk_alloc_queue(GFP_KERNEL);
2793	if (!disk->queue)
2794		goto out_mem2;
2795
2796	pd->pkt_dev = MKDEV(pktdev_major, idx);
2797	ret = pkt_new_dev(pd, dev);
2798	if (ret)
2799		goto out_new_dev;
2800
2801	/* inherit events of the host device */
2802	disk->events = pd->bdev->bd_disk->events;
2803	disk->async_events = pd->bdev->bd_disk->async_events;
2804
2805	add_disk(disk);
2806
2807	pkt_sysfs_dev_new(pd);
2808	pkt_debugfs_dev_new(pd);
2809
2810	pkt_devs[idx] = pd;
2811	if (pkt_dev)
2812		*pkt_dev = pd->pkt_dev;
2813
2814	mutex_unlock(&ctl_mutex);
2815	return 0;
2816
2817out_new_dev:
2818	blk_cleanup_queue(disk->queue);
2819out_mem2:
2820	put_disk(disk);
2821out_mem:
2822	if (pd->rb_pool)
2823		mempool_destroy(pd->rb_pool);
2824	kfree(pd);
2825out_mutex:
2826	mutex_unlock(&ctl_mutex);
2827	pr_err("setup of pktcdvd device failed\n");
2828	return ret;
2829}
2830
2831/*
2832 * Tear down mapping from pktcdvd device to CD-ROM device.
2833 */
2834static int pkt_remove_dev(dev_t pkt_dev)
2835{
2836	struct pktcdvd_device *pd;
2837	int idx;
2838	int ret = 0;
2839
2840	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2841
2842	for (idx = 0; idx < MAX_WRITERS; idx++) {
2843		pd = pkt_devs[idx];
2844		if (pd && (pd->pkt_dev == pkt_dev))
2845			break;
2846	}
2847	if (idx == MAX_WRITERS) {
2848		pr_debug("dev not setup\n");
2849		ret = -ENXIO;
2850		goto out;
2851	}
2852
2853	if (pd->refcnt > 0) {
2854		ret = -EBUSY;
2855		goto out;
2856	}
2857	if (!IS_ERR(pd->cdrw.thread))
2858		kthread_stop(pd->cdrw.thread);
2859
2860	pkt_devs[idx] = NULL;
2861
2862	pkt_debugfs_dev_remove(pd);
2863	pkt_sysfs_dev_remove(pd);
2864
2865	blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2866
2867	remove_proc_entry(pd->name, pkt_proc);
2868	pkt_dbg(1, pd, "writer unmapped\n");
2869
2870	del_gendisk(pd->disk);
2871	blk_cleanup_queue(pd->disk->queue);
2872	put_disk(pd->disk);
2873
2874	mempool_destroy(pd->rb_pool);
2875	kfree(pd);
2876
2877	/* This is safe: open() is still holding a reference. */
2878	module_put(THIS_MODULE);
2879
2880out:
2881	mutex_unlock(&ctl_mutex);
2882	return ret;
2883}
2884
2885static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2886{
2887	struct pktcdvd_device *pd;
2888
2889	mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2890
2891	pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2892	if (pd) {
2893		ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2894		ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2895	} else {
2896		ctrl_cmd->dev = 0;
2897		ctrl_cmd->pkt_dev = 0;
2898	}
2899	ctrl_cmd->num_devices = MAX_WRITERS;
2900
2901	mutex_unlock(&ctl_mutex);
2902}
2903
2904static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2905{
2906	void __user *argp = (void __user *)arg;
2907	struct pkt_ctrl_command ctrl_cmd;
2908	int ret = 0;
2909	dev_t pkt_dev = 0;
2910
2911	if (cmd != PACKET_CTRL_CMD)
2912		return -ENOTTY;
2913
2914	if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2915		return -EFAULT;
2916
2917	switch (ctrl_cmd.command) {
2918	case PKT_CTRL_CMD_SETUP:
2919		if (!capable(CAP_SYS_ADMIN))
2920			return -EPERM;
2921		ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2922		ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2923		break;
2924	case PKT_CTRL_CMD_TEARDOWN:
2925		if (!capable(CAP_SYS_ADMIN))
2926			return -EPERM;
2927		ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2928		break;
2929	case PKT_CTRL_CMD_STATUS:
2930		pkt_get_status(&ctrl_cmd);
2931		break;
2932	default:
2933		return -ENOTTY;
2934	}
2935
2936	if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2937		return -EFAULT;
2938	return ret;
2939}
2940
2941#ifdef CONFIG_COMPAT
2942static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2943{
2944	return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2945}
2946#endif
2947
2948static const struct file_operations pkt_ctl_fops = {
2949	.open		= nonseekable_open,
2950	.unlocked_ioctl	= pkt_ctl_ioctl,
2951#ifdef CONFIG_COMPAT
2952	.compat_ioctl	= pkt_ctl_compat_ioctl,
2953#endif
2954	.owner		= THIS_MODULE,
2955	.llseek		= no_llseek,
2956};
2957
2958static struct miscdevice pkt_misc = {
2959	.minor 		= MISC_DYNAMIC_MINOR,
2960	.name  		= DRIVER_NAME,
2961	.nodename	= "pktcdvd/control",
2962	.fops  		= &pkt_ctl_fops
2963};
2964
2965static int __init pkt_init(void)
2966{
2967	int ret;
2968
2969	mutex_init(&ctl_mutex);
2970
2971	psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
2972					sizeof(struct packet_stacked_data));
2973	if (!psd_pool)
2974		return -ENOMEM;
2975
2976	ret = register_blkdev(pktdev_major, DRIVER_NAME);
2977	if (ret < 0) {
2978		pr_err("unable to register block device\n");
2979		goto out2;
2980	}
2981	if (!pktdev_major)
2982		pktdev_major = ret;
2983
2984	ret = pkt_sysfs_init();
2985	if (ret)
2986		goto out;
2987
2988	pkt_debugfs_init();
2989
2990	ret = misc_register(&pkt_misc);
2991	if (ret) {
2992		pr_err("unable to register misc device\n");
2993		goto out_misc;
2994	}
2995
2996	pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
2997
2998	return 0;
2999
3000out_misc:
3001	pkt_debugfs_cleanup();
3002	pkt_sysfs_cleanup();
3003out:
3004	unregister_blkdev(pktdev_major, DRIVER_NAME);
3005out2:
3006	mempool_destroy(psd_pool);
3007	return ret;
3008}
3009
3010static void __exit pkt_exit(void)
3011{
3012	remove_proc_entry("driver/"DRIVER_NAME, NULL);
3013	misc_deregister(&pkt_misc);
3014
3015	pkt_debugfs_cleanup();
3016	pkt_sysfs_cleanup();
3017
3018	unregister_blkdev(pktdev_major, DRIVER_NAME);
3019	mempool_destroy(psd_pool);
3020}
3021
3022MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3023MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3024MODULE_LICENSE("GPL");
3025
3026module_init(pkt_init);
3027module_exit(pkt_exit);