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