drivers/block/pktcdvd.c

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