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