Pileus Git - ~andy/linux/blob - drivers/block/pktcdvd.c

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