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