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 #include <linux/pktcdvd.h>
  48 #include <linux/module.h>
  49 #include <linux/types.h>
  50 #include <linux/kernel.h>
  51 #include <linux/compat.h>
  52 #include <linux/kthread.h>
  53 #include <linux/errno.h>
  54 #include <linux/spinlock.h>
  55 #include <linux/file.h>
  56 #include <linux/proc_fs.h>
  57 #include <linux/seq_file.h>
  58 #include <linux/miscdevice.h>
  59 #include <linux/freezer.h>
  60 #include <linux/mutex.h>
  61 #include <linux/slab.h>
  62 #include <scsi/scsi_cmnd.h>
  63 #include <scsi/scsi_ioctl.h>
  64 #include <scsi/scsi.h>
  65 #include <linux/debugfs.h>
  66 #include <linux/device.h>
  67
  68 #include <asm/uaccess.h>
  69
  70 #define DRIVER_NAME     "pktcdvd"
  71
  72 #if PACKET_DEBUG
  73 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  74 #else
  75 #define DPRINTK(fmt, args...)
  76 #endif
  77
  78 #if PACKET_DEBUG > 1
  79 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  80 #else
  81 #define VPRINTK(fmt, args...)
  82 #endif
  83
  84 #define MAX_SPEED 0xffff
  85
  86 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  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
 106
 107 /*
 108  * create and register a pktcdvd kernel object.
 109  */
 110 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
 111                                         const char* name,
 112                                         struct kobject* parent,
 113                                         struct kobj_type* ktype)
 114 {
 115         struct pktcdvd_kobj *p;
 116         int error;
 117
 118         p = kzalloc(sizeof(*p), GFP_KERNEL);
 119         if (!p)
 120                 return NULL;
 121         p->pd = pd;
 122         error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
 123         if (error) {
 124                 kobject_put(&p->kobj);
 125                 return NULL;
 126         }
 127         kobject_uevent(&p->kobj, KOBJ_ADD);
 128         return p;
 129 }
 130 /*
 131  * remove a pktcdvd kernel object.
 132  */
 133 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 134 {
 135         if (p)
 136                 kobject_put(&p->kobj);
 137 }
 138 /*
 139  * default release function for pktcdvd kernel objects.
 140  */
 141 static void pkt_kobj_release(struct kobject *kobj)
 142 {
 143         kfree(to_pktcdvdkobj(kobj));
 144 }
 145
 146
 147 /**********************************************************
 148  *
 149  * sysfs interface for pktcdvd
 150  * by (C) 2006  Thomas Maier <balagi@justmail.de>
 151  *
 152  **********************************************************/
 153
 154 #define DEF_ATTR(_obj,_name,_mode) \
 155         static struct attribute _obj = { .name = _name, .mode = _mode }
 156
 157 /**********************************************************
 158   /sys/class/pktcdvd/pktcdvd[0-7]/
 159                      stat/reset
 160                      stat/packets_started
 161                      stat/packets_finished
 162                      stat/kb_written
 163                      stat/kb_read
 164                      stat/kb_read_gather
 165                      write_queue/size
 166                      write_queue/congestion_off
 167                      write_queue/congestion_on
 168  **********************************************************/
 169
 170 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 171 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 172 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 173 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 174 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 175 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 176
 177 static struct attribute *kobj_pkt_attrs_stat[] = {
 178         &kobj_pkt_attr_st1,
 179         &kobj_pkt_attr_st2,
 180         &kobj_pkt_attr_st3,
 181         &kobj_pkt_attr_st4,
 182         &kobj_pkt_attr_st5,
 183         &kobj_pkt_attr_st6,
 184         NULL
 185 };
 186
 187 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 188 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 189 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 190
 191 static struct attribute *kobj_pkt_attrs_wqueue[] = {
 192         &kobj_pkt_attr_wq1,
 193         &kobj_pkt_attr_wq2,
 194         &kobj_pkt_attr_wq3,
 195         NULL
 196 };
 197
 198 static ssize_t kobj_pkt_show(struct kobject *kobj,
 199                         struct attribute *attr, char *data)
 200 {
 201         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 202         int n = 0;
 203         int v;
 204         if (strcmp(attr->name, "packets_started") == 0) {
 205                 n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 206
 207         } else if (strcmp(attr->name, "packets_finished") == 0) {
 208                 n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 209
 210         } else if (strcmp(attr->name, "kb_written") == 0) {
 211                 n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 212
 213         } else if (strcmp(attr->name, "kb_read") == 0) {
 214                 n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 215
 216         } else if (strcmp(attr->name, "kb_read_gather") == 0) {
 217                 n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 218
 219         } else if (strcmp(attr->name, "size") == 0) {
 220                 spin_lock(&pd->lock);
 221                 v = pd->bio_queue_size;
 222                 spin_unlock(&pd->lock);
 223                 n = sprintf(data, "%d\n", v);
 224
 225         } else if (strcmp(attr->name, "congestion_off") == 0) {
 226                 spin_lock(&pd->lock);
 227                 v = pd->write_congestion_off;
 228                 spin_unlock(&pd->lock);
 229                 n = sprintf(data, "%d\n", v);
 230
 231         } else if (strcmp(attr->name, "congestion_on") == 0) {
 232                 spin_lock(&pd->lock);
 233                 v = pd->write_congestion_on;
 234                 spin_unlock(&pd->lock);
 235                 n = sprintf(data, "%d\n", v);
 236         }
 237         return n;
 238 }
 239
 240 static void init_write_congestion_marks(int* lo, int* hi)
 241 {
 242         if (*hi > 0) {
 243                 *hi = max(*hi, 500);
 244                 *hi = min(*hi, 1000000);
 245                 if (*lo <= 0)
 246                         *lo = *hi - 100;
 247                 else {
 248                         *lo = min(*lo, *hi - 100);
 249                         *lo = max(*lo, 100);
 250                 }
 251         } else {
 252                 *hi = -1;
 253                 *lo = -1;
 254         }
 255 }
 256
 257 static ssize_t kobj_pkt_store(struct kobject *kobj,
 258                         struct attribute *attr,
 259                         const char *data, size_t len)
 260 {
 261         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 262         int val;
 263
 264         if (strcmp(attr->name, "reset") == 0 && len > 0) {
 265                 pd->stats.pkt_started = 0;
 266                 pd->stats.pkt_ended = 0;
 267                 pd->stats.secs_w = 0;
 268                 pd->stats.secs_rg = 0;
 269                 pd->stats.secs_r = 0;
 270
 271         } else if (strcmp(attr->name, "congestion_off") == 0
 272                    && sscanf(data, "%d", &val) == 1) {
 273                 spin_lock(&pd->lock);
 274                 pd->write_congestion_off = val;
 275                 init_write_congestion_marks(&pd->write_congestion_off,
 276                                         &pd->write_congestion_on);
 277                 spin_unlock(&pd->lock);
 278
 279         } else if (strcmp(attr->name, "congestion_on") == 0
 280                    && sscanf(data, "%d", &val) == 1) {
 281                 spin_lock(&pd->lock);
 282                 pd->write_congestion_on = val;
 283                 init_write_congestion_marks(&pd->write_congestion_off,
 284                                         &pd->write_congestion_on);
 285                 spin_unlock(&pd->lock);
 286         }
 287         return len;
 288 }
 289
 290 static const struct sysfs_ops kobj_pkt_ops = {
 291         .show = kobj_pkt_show,
 292         .store = kobj_pkt_store
 293 };
 294 static struct kobj_type kobj_pkt_type_stat = {
 295         .release = pkt_kobj_release,
 296         .sysfs_ops = &kobj_pkt_ops,
 297         .default_attrs = kobj_pkt_attrs_stat
 298 };
 299 static struct kobj_type kobj_pkt_type_wqueue = {
 300         .release = pkt_kobj_release,
 301         .sysfs_ops = &kobj_pkt_ops,
 302         .default_attrs = kobj_pkt_attrs_wqueue
 303 };
 304
 305 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 306 {
 307         if (class_pktcdvd) {
 308                 pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
 309                                         "%s", pd->name);
 310                 if (IS_ERR(pd->dev))
 311                         pd->dev = NULL;
 312         }
 313         if (pd->dev) {
 314                 pd->kobj_stat = pkt_kobj_create(pd, "stat",
 315                                         &pd->dev->kobj,
 316                                         &kobj_pkt_type_stat);
 317                 pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 318                                         &pd->dev->kobj,
 319                                         &kobj_pkt_type_wqueue);
 320         }
 321 }
 322
 323 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 324 {
 325         pkt_kobj_remove(pd->kobj_stat);
 326         pkt_kobj_remove(pd->kobj_wqueue);
 327         if (class_pktcdvd)
 328                 device_unregister(pd->dev);
 329 }
 330
 331
 332 /********************************************************************
 333   /sys/class/pktcdvd/
 334                      add            map block device
 335                      remove         unmap packet dev
 336                      device_map     show mappings
 337  *******************************************************************/
 338
 339 static void class_pktcdvd_release(struct class *cls)
 340 {
 341         kfree(cls);
 342 }
 343 static ssize_t class_pktcdvd_show_map(struct class *c,
 344                                         struct class_attribute *attr,
 345                                         char *data)
 346 {
 347         int n = 0;
 348         int idx;
 349         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 350         for (idx = 0; idx < MAX_WRITERS; idx++) {
 351                 struct pktcdvd_device *pd = pkt_devs[idx];
 352                 if (!pd)
 353                         continue;
 354                 n += sprintf(data+n, "%s %u:%u %u:%u\n",
 355                         pd->name,
 356                         MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 357                         MAJOR(pd->bdev->bd_dev),
 358                         MINOR(pd->bdev->bd_dev));
 359         }
 360         mutex_unlock(&ctl_mutex);
 361         return n;
 362 }
 363
 364 static ssize_t class_pktcdvd_store_add(struct class *c,
 365                                         struct class_attribute *attr,
 366                                         const char *buf,
 367                                         size_t count)
 368 {
 369         unsigned int major, minor;
 370
 371         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 372                 /* pkt_setup_dev() expects caller to hold reference to self */
 373                 if (!try_module_get(THIS_MODULE))
 374                         return -ENODEV;
 375
 376                 pkt_setup_dev(MKDEV(major, minor), NULL);
 377
 378                 module_put(THIS_MODULE);
 379
 380                 return count;
 381         }
 382
 383         return -EINVAL;
 384 }
 385
 386 static ssize_t class_pktcdvd_store_remove(struct class *c,
 387                                           struct class_attribute *attr,
 388                                           const char *buf,
 389                                         size_t count)
 390 {
 391         unsigned int major, minor;
 392         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 393                 pkt_remove_dev(MKDEV(major, minor));
 394                 return count;
 395         }
 396         return -EINVAL;
 397 }
 398
 399 static struct class_attribute class_pktcdvd_attrs[] = {
 400  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 401  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 402  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 403  __ATTR_NULL
 404 };
 405
 406
 407 static int pkt_sysfs_init(void)
 408 {
 409         int ret = 0;
 410
 411         /*
 412          * create control files in sysfs
 413          * /sys/class/pktcdvd/...
 414          */
 415         class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 416         if (!class_pktcdvd)
 417                 return -ENOMEM;
 418         class_pktcdvd->name = DRIVER_NAME;
 419         class_pktcdvd->owner = THIS_MODULE;
 420         class_pktcdvd->class_release = class_pktcdvd_release;
 421         class_pktcdvd->class_attrs = class_pktcdvd_attrs;
 422         ret = class_register(class_pktcdvd);
 423         if (ret) {
 424                 kfree(class_pktcdvd);
 425                 class_pktcdvd = NULL;
 426                 printk(DRIVER_NAME": failed to create class pktcdvd\n");
 427                 return ret;
 428         }
 429         return 0;
 430 }
 431
 432 static void pkt_sysfs_cleanup(void)
 433 {
 434         if (class_pktcdvd)
 435                 class_destroy(class_pktcdvd);
 436         class_pktcdvd = NULL;
 437 }
 438
 439 /********************************************************************
 440   entries in debugfs
 441
 442   /sys/kernel/debug/pktcdvd[0-7]/
 443                         info
 444
 445  *******************************************************************/
 446
 447 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 448 {
 449         return pkt_seq_show(m, p);
 450 }
 451
 452 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 453 {
 454         return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 455 }
 456
 457 static const struct file_operations debug_fops = {
 458         .open           = pkt_debugfs_fops_open,
 459         .read           = seq_read,
 460         .llseek         = seq_lseek,
 461         .release        = single_release,
 462         .owner          = THIS_MODULE,
 463 };
 464
 465 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 466 {
 467         if (!pkt_debugfs_root)
 468                 return;
 469         pd->dfs_f_info = NULL;
 470         pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 471         if (IS_ERR(pd->dfs_d_root)) {
 472                 pd->dfs_d_root = NULL;
 473                 return;
 474         }
 475         pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
 476                                 pd->dfs_d_root, pd, &debug_fops);
 477         if (IS_ERR(pd->dfs_f_info)) {
 478                 pd->dfs_f_info = NULL;
 479                 return;
 480         }
 481 }
 482
 483 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 484 {
 485         if (!pkt_debugfs_root)
 486                 return;
 487         if (pd->dfs_f_info)
 488                 debugfs_remove(pd->dfs_f_info);
 489         pd->dfs_f_info = NULL;
 490         if (pd->dfs_d_root)
 491                 debugfs_remove(pd->dfs_d_root);
 492         pd->dfs_d_root = NULL;
 493 }
 494
 495 static void pkt_debugfs_init(void)
 496 {
 497         pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 498         if (IS_ERR(pkt_debugfs_root)) {
 499                 pkt_debugfs_root = NULL;
 500                 return;
 501         }
 502 }
 503
 504 static void pkt_debugfs_cleanup(void)
 505 {
 506         if (!pkt_debugfs_root)
 507                 return;
 508         debugfs_remove(pkt_debugfs_root);
 509         pkt_debugfs_root = NULL;
 510 }
 511
 512 /* ----------------------------------------------------------*/
 513
 514
 515 static void pkt_bio_finished(struct pktcdvd_device *pd)
 516 {
 517         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 518         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 519                 VPRINTK(DRIVER_NAME": queue empty\n");
 520                 atomic_set(&pd->iosched.attention, 1);
 521                 wake_up(&pd->wqueue);
 522         }
 523 }
 524
 525 /*
 526  * Allocate a packet_data struct
 527  */
 528 static struct packet_data *pkt_alloc_packet_data(int frames)
 529 {
 530         int i;
 531         struct packet_data *pkt;
 532
 533         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 534         if (!pkt)
 535                 goto no_pkt;
 536
 537         pkt->frames = frames;
 538         pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
 539         if (!pkt->w_bio)
 540                 goto no_bio;
 541
 542         for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 543                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 544                 if (!pkt->pages[i])
 545                         goto no_page;
 546         }
 547
 548         spin_lock_init(&pkt->lock);
 549         bio_list_init(&pkt->orig_bios);
 550
 551         for (i = 0; i < frames; i++) {
 552                 struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
 553                 if (!bio)
 554                         goto no_rd_bio;
 555
 556                 pkt->r_bios[i] = bio;
 557         }
 558
 559         return pkt;
 560
 561 no_rd_bio:
 562         for (i = 0; i < frames; i++) {
 563                 struct bio *bio = pkt->r_bios[i];
 564                 if (bio)
 565                         bio_put(bio);
 566         }
 567
 568 no_page:
 569         for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 570                 if (pkt->pages[i])
 571                         __free_page(pkt->pages[i]);
 572         bio_put(pkt->w_bio);
 573 no_bio:
 574         kfree(pkt);
 575 no_pkt:
 576         return NULL;
 577 }
 578
 579 /*
 580  * Free a packet_data struct
 581  */
 582 static void pkt_free_packet_data(struct packet_data *pkt)
 583 {
 584         int i;
 585
 586         for (i = 0; i < pkt->frames; i++) {
 587                 struct bio *bio = pkt->r_bios[i];
 588                 if (bio)
 589                         bio_put(bio);
 590         }
 591         for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 592                 __free_page(pkt->pages[i]);
 593         bio_put(pkt->w_bio);
 594         kfree(pkt);
 595 }
 596
 597 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 598 {
 599         struct packet_data *pkt, *next;
 600
 601         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 602
 603         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 604                 pkt_free_packet_data(pkt);
 605         }
 606         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 607 }
 608
 609 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 610 {
 611         struct packet_data *pkt;
 612
 613         BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 614
 615         while (nr_packets > 0) {
 616                 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 617                 if (!pkt) {
 618                         pkt_shrink_pktlist(pd);
 619                         return 0;
 620                 }
 621                 pkt->id = nr_packets;
 622                 pkt->pd = pd;
 623                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 624                 nr_packets--;
 625         }
 626         return 1;
 627 }
 628
 629 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 630 {
 631         struct rb_node *n = rb_next(&node->rb_node);
 632         if (!n)
 633                 return NULL;
 634         return rb_entry(n, struct pkt_rb_node, rb_node);
 635 }
 636
 637 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 638 {
 639         rb_erase(&node->rb_node, &pd->bio_queue);
 640         mempool_free(node, pd->rb_pool);
 641         pd->bio_queue_size--;
 642         BUG_ON(pd->bio_queue_size < 0);
 643 }
 644
 645 /*
 646  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 647  */
 648 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 649 {
 650         struct rb_node *n = pd->bio_queue.rb_node;
 651         struct rb_node *next;
 652         struct pkt_rb_node *tmp;
 653
 654         if (!n) {
 655                 BUG_ON(pd->bio_queue_size > 0);
 656                 return NULL;
 657         }
 658
 659         for (;;) {
 660                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 661                 if (s <= tmp->bio->bi_sector)
 662                         next = n->rb_left;
 663                 else
 664                         next = n->rb_right;
 665                 if (!next)
 666                         break;
 667                 n = next;
 668         }
 669
 670         if (s > tmp->bio->bi_sector) {
 671                 tmp = pkt_rbtree_next(tmp);
 672                 if (!tmp)
 673                         return NULL;
 674         }
 675         BUG_ON(s > tmp->bio->bi_sector);
 676         return tmp;
 677 }
 678
 679 /*
 680  * Insert a node into the pd->bio_queue rb tree.
 681  */
 682 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 683 {
 684         struct rb_node **p = &pd->bio_queue.rb_node;
 685         struct rb_node *parent = NULL;
 686         sector_t s = node->bio->bi_sector;
 687         struct pkt_rb_node *tmp;
 688
 689         while (*p) {
 690                 parent = *p;
 691                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 692                 if (s < tmp->bio->bi_sector)
 693                         p = &(*p)->rb_left;
 694                 else
 695                         p = &(*p)->rb_right;
 696         }
 697         rb_link_node(&node->rb_node, parent, p);
 698         rb_insert_color(&node->rb_node, &pd->bio_queue);
 699         pd->bio_queue_size++;
 700 }
 701
 702 /*
 703  * Send a packet_command to the underlying block device and
 704  * wait for completion.
 705  */
 706 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 707 {
 708         struct request_queue *q = bdev_get_queue(pd->bdev);
 709         struct request *rq;
 710         int ret = 0;
 711
 712         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 713                              WRITE : READ, __GFP_WAIT);
 714
 715         if (cgc->buflen) {
 716                 if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
 717                         goto out;
 718         }
 719
 720         rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 721         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 722
 723         rq->timeout = 60*HZ;
 724         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 725         if (cgc->quiet)
 726                 rq->cmd_flags |= REQ_QUIET;
 727
 728         blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 729         if (rq->errors)
 730                 ret = -EIO;
 731 out:
 732         blk_put_request(rq);
 733         return ret;
 734 }
 735
 736 /*
 737  * A generic sense dump / resolve mechanism should be implemented across
 738  * all ATAPI + SCSI devices.
 739  */
 740 static void pkt_dump_sense(struct packet_command *cgc)
 741 {
 742         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 743                                  "Medium error", "Hardware error", "Illegal request",
 744                                  "Unit attention", "Data protect", "Blank check" };
 745         int i;
 746         struct request_sense *sense = cgc->sense;
 747
 748         printk(DRIVER_NAME":");
 749         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 750                 printk(" %02x", cgc->cmd[i]);
 751         printk(" - ");
 752
 753         if (sense == NULL) {
 754                 printk("no sense\n");
 755                 return;
 756         }
 757
 758         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 759
 760         if (sense->sense_key > 8) {
 761                 printk(" (INVALID)\n");
 762                 return;
 763         }
 764
 765         printk(" (%s)\n", info[sense->sense_key]);
 766 }
 767
 768 /*
 769  * flush the drive cache to media
 770  */
 771 static int pkt_flush_cache(struct pktcdvd_device *pd)
 772 {
 773         struct packet_command cgc;
 774
 775         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 776         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 777         cgc.quiet = 1;
 778
 779         /*
 780          * the IMMED bit -- we default to not setting it, although that
 781          * would allow a much faster close, this is safer
 782          */
 783 #if 0
 784         cgc.cmd[1] = 1 << 1;
 785 #endif
 786         return pkt_generic_packet(pd, &cgc);
 787 }
 788
 789 /*
 790  * speed is given as the normal factor, e.g. 4 for 4x
 791  */
 792 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 793                                 unsigned write_speed, unsigned read_speed)
 794 {
 795         struct packet_command cgc;
 796         struct request_sense sense;
 797         int ret;
 798
 799         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 800         cgc.sense = &sense;
 801         cgc.cmd[0] = GPCMD_SET_SPEED;
 802         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 803         cgc.cmd[3] = read_speed & 0xff;
 804         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 805         cgc.cmd[5] = write_speed & 0xff;
 806
 807         if ((ret = pkt_generic_packet(pd, &cgc)))
 808                 pkt_dump_sense(&cgc);
 809
 810         return ret;
 811 }
 812
 813 /*
 814  * Queue a bio for processing by the low-level CD device. Must be called
 815  * from process context.
 816  */
 817 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 818 {
 819         spin_lock(&pd->iosched.lock);
 820         if (bio_data_dir(bio) == READ)
 821                 bio_list_add(&pd->iosched.read_queue, bio);
 822         else
 823                 bio_list_add(&pd->iosched.write_queue, bio);
 824         spin_unlock(&pd->iosched.lock);
 825
 826         atomic_set(&pd->iosched.attention, 1);
 827         wake_up(&pd->wqueue);
 828 }
 829
 830 /*
 831  * Process the queued read/write requests. This function handles special
 832  * requirements for CDRW drives:
 833  * - A cache flush command must be inserted before a read request if the
 834  *   previous request was a write.
 835  * - Switching between reading and writing is slow, so don't do it more often
 836  *   than necessary.
 837  * - Optimize for throughput at the expense of latency. This means that streaming
 838  *   writes will never be interrupted by a read, but if the drive has to seek
 839  *   before the next write, switch to reading instead if there are any pending
 840  *   read requests.
 841  * - Set the read speed according to current usage pattern. When only reading
 842  *   from the device, it's best to use the highest possible read speed, but
 843  *   when switching often between reading and writing, it's better to have the
 844  *   same read and write speeds.
 845  */
 846 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 847 {
 848
 849         if (atomic_read(&pd->iosched.attention) == 0)
 850                 return;
 851         atomic_set(&pd->iosched.attention, 0);
 852
 853         for (;;) {
 854                 struct bio *bio;
 855                 int reads_queued, writes_queued;
 856
 857                 spin_lock(&pd->iosched.lock);
 858                 reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 859                 writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 860                 spin_unlock(&pd->iosched.lock);
 861
 862                 if (!reads_queued && !writes_queued)
 863                         break;
 864
 865                 if (pd->iosched.writing) {
 866                         int need_write_seek = 1;
 867                         spin_lock(&pd->iosched.lock);
 868                         bio = bio_list_peek(&pd->iosched.write_queue);
 869                         spin_unlock(&pd->iosched.lock);
 870                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 871                                 need_write_seek = 0;
 872                         if (need_write_seek && reads_queued) {
 873                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 874                                         VPRINTK(DRIVER_NAME": write, waiting\n");
 875                                         break;
 876                                 }
 877                                 pkt_flush_cache(pd);
 878                                 pd->iosched.writing = 0;
 879                         }
 880                 } else {
 881                         if (!reads_queued && writes_queued) {
 882                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 883                                         VPRINTK(DRIVER_NAME": read, waiting\n");
 884                                         break;
 885                                 }
 886                                 pd->iosched.writing = 1;
 887                         }
 888                 }
 889
 890                 spin_lock(&pd->iosched.lock);
 891                 if (pd->iosched.writing)
 892                         bio = bio_list_pop(&pd->iosched.write_queue);
 893                 else
 894                         bio = bio_list_pop(&pd->iosched.read_queue);
 895                 spin_unlock(&pd->iosched.lock);
 896
 897                 if (!bio)
 898                         continue;
 899
 900                 if (bio_data_dir(bio) == READ)
 901                         pd->iosched.successive_reads += bio->bi_size >> 10;
 902                 else {
 903                         pd->iosched.successive_reads = 0;
 904                         pd->iosched.last_write = bio_end_sector(bio);
 905                 }
 906                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 907                         if (pd->read_speed == pd->write_speed) {
 908                                 pd->read_speed = MAX_SPEED;
 909                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 910                         }
 911                 } else {
 912                         if (pd->read_speed != pd->write_speed) {
 913                                 pd->read_speed = pd->write_speed;
 914                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 915                         }
 916                 }
 917
 918                 atomic_inc(&pd->cdrw.pending_bios);
 919                 generic_make_request(bio);
 920         }
 921 }
 922
 923 /*
 924  * Special care is needed if the underlying block device has a small
 925  * max_phys_segments value.
 926  */
 927 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 928 {
 929         if ((pd->settings.size << 9) / CD_FRAMESIZE
 930             <= queue_max_segments(q)) {
 931                 /*
 932                  * The cdrom device can handle one segment/frame
 933                  */
 934                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 935                 return 0;
 936         } else if ((pd->settings.size << 9) / PAGE_SIZE
 937                    <= queue_max_segments(q)) {
 938                 /*
 939                  * We can handle this case at the expense of some extra memory
 940                  * copies during write operations
 941                  */
 942                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 943                 return 0;
 944         } else {
 945                 printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
 946                 return -EIO;
 947         }
 948 }
 949
 950 /*
 951  * Copy all data for this packet to pkt->pages[], so that
 952  * a) The number of required segments for the write bio is minimized, which
 953  *    is necessary for some scsi controllers.
 954  * b) The data can be used as cache to avoid read requests if we receive a
 955  *    new write request for the same zone.
 956  */
 957 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
 958 {
 959         int f, p, offs;
 960
 961         /* Copy all data to pkt->pages[] */
 962         p = 0;
 963         offs = 0;
 964         for (f = 0; f < pkt->frames; f++) {
 965                 if (bvec[f].bv_page != pkt->pages[p]) {
 966                         void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset;
 967                         void *vto = page_address(pkt->pages[p]) + offs;
 968                         memcpy(vto, vfrom, CD_FRAMESIZE);
 969                         kunmap_atomic(vfrom);
 970                         bvec[f].bv_page = pkt->pages[p];
 971                         bvec[f].bv_offset = offs;
 972                 } else {
 973                         BUG_ON(bvec[f].bv_offset != offs);
 974                 }
 975                 offs += CD_FRAMESIZE;
 976                 if (offs >= PAGE_SIZE) {
 977                         offs = 0;
 978                         p++;
 979                 }
 980         }
 981 }
 982
 983 static void pkt_end_io_read(struct bio *bio, int err,
 984                             struct batch_complete *batch)
 985 {
 986         struct packet_data *pkt = bio->bi_private;
 987         struct pktcdvd_device *pd = pkt->pd;
 988         BUG_ON(!pd);
 989
 990         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
 991                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
 992
 993         if (err)
 994                 atomic_inc(&pkt->io_errors);
 995         if (atomic_dec_and_test(&pkt->io_wait)) {
 996                 atomic_inc(&pkt->run_sm);
 997                 wake_up(&pd->wqueue);
 998         }
 999         pkt_bio_finished(pd);
1000 }
1001
1002 static void pkt_end_io_packet_write(struct bio *bio, int err,
1003                                     struct batch_complete *batch)
1004 {
1005         struct packet_data *pkt = bio->bi_private;
1006         struct pktcdvd_device *pd = pkt->pd;
1007         BUG_ON(!pd);
1008
1009         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1010
1011         pd->stats.pkt_ended++;
1012
1013         pkt_bio_finished(pd);
1014         atomic_dec(&pkt->io_wait);
1015         atomic_inc(&pkt->run_sm);
1016         wake_up(&pd->wqueue);
1017 }
1018
1019 /*
1020  * Schedule reads for the holes in a packet
1021  */
1022 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1023 {
1024         int frames_read = 0;
1025         struct bio *bio;
1026         int f;
1027         char written[PACKET_MAX_SIZE];
1028
1029         BUG_ON(bio_list_empty(&pkt->orig_bios));
1030
1031         atomic_set(&pkt->io_wait, 0);
1032         atomic_set(&pkt->io_errors, 0);
1033
1034         /*
1035          * Figure out which frames we need to read before we can write.
1036          */
1037         memset(written, 0, sizeof(written));
1038         spin_lock(&pkt->lock);
1039         bio_list_for_each(bio, &pkt->orig_bios) {
1040                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1041                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1042                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1043                 BUG_ON(first_frame < 0);
1044                 BUG_ON(first_frame + num_frames > pkt->frames);
1045                 for (f = first_frame; f < first_frame + num_frames; f++)
1046                         written[f] = 1;
1047         }
1048         spin_unlock(&pkt->lock);
1049
1050         if (pkt->cache_valid) {
1051                 VPRINTK("pkt_gather_data: zone %llx cached\n",
1052                         (unsigned long long)pkt->sector);
1053                 goto out_account;
1054         }
1055
1056         /*
1057          * Schedule reads for missing parts of the packet.
1058          */
1059         for (f = 0; f < pkt->frames; f++) {
1060                 int p, offset;
1061
1062                 if (written[f])
1063                         continue;
1064
1065                 bio = pkt->r_bios[f];
1066                 bio_reset(bio);
1067                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1068                 bio->bi_bdev = pd->bdev;
1069                 bio->bi_end_io = pkt_end_io_read;
1070                 bio->bi_private = pkt;
1071
1072                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1073                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1074                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1075                         f, pkt->pages[p], offset);
1076                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1077                         BUG();
1078
1079                 atomic_inc(&pkt->io_wait);
1080                 bio->bi_rw = READ;
1081                 pkt_queue_bio(pd, bio);
1082                 frames_read++;
1083         }
1084
1085 out_account:
1086         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1087                 frames_read, (unsigned long long)pkt->sector);
1088         pd->stats.pkt_started++;
1089         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1090 }
1091
1092 /*
1093  * Find a packet matching zone, or the least recently used packet if
1094  * there is no match.
1095  */
1096 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1097 {
1098         struct packet_data *pkt;
1099
1100         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1101                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1102                         list_del_init(&pkt->list);
1103                         if (pkt->sector != zone)
1104                                 pkt->cache_valid = 0;
1105                         return pkt;
1106                 }
1107         }
1108         BUG();
1109         return NULL;
1110 }
1111
1112 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1113 {
1114         if (pkt->cache_valid) {
1115                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1116         } else {
1117                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1118         }
1119 }
1120
1121 /*
1122  * recover a failed write, query for relocation if possible
1123  *
1124  * returns 1 if recovery is possible, or 0 if not
1125  *
1126  */
1127 static int pkt_start_recovery(struct packet_data *pkt)
1128 {
1129         /*
1130          * FIXME. We need help from the file system to implement
1131          * recovery handling.
1132          */
1133         return 0;
1134 #if 0
1135         struct request *rq = pkt->rq;
1136         struct pktcdvd_device *pd = rq->rq_disk->private_data;
1137         struct block_device *pkt_bdev;
1138         struct super_block *sb = NULL;
1139         unsigned long old_block, new_block;
1140         sector_t new_sector;
1141
1142         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1143         if (pkt_bdev) {
1144                 sb = get_super(pkt_bdev);
1145                 bdput(pkt_bdev);
1146         }
1147
1148         if (!sb)
1149                 return 0;
1150
1151         if (!sb->s_op->relocate_blocks)
1152                 goto out;
1153
1154         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1155         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1156                 goto out;
1157
1158         new_sector = new_block * (CD_FRAMESIZE >> 9);
1159         pkt->sector = new_sector;
1160
1161         bio_reset(pkt->bio);
1162         pkt->bio->bi_bdev = pd->bdev;
1163         pkt->bio->bi_rw = REQ_WRITE;
1164         pkt->bio->bi_sector = new_sector;
1165         pkt->bio->bi_size = pkt->frames * CD_FRAMESIZE;
1166         pkt->bio->bi_vcnt = pkt->frames;
1167
1168         pkt->bio->bi_end_io = pkt_end_io_packet_write;
1169         pkt->bio->bi_private = pkt;
1170
1171         drop_super(sb);
1172         return 1;
1173
1174 out:
1175         drop_super(sb);
1176         return 0;
1177 #endif
1178 }
1179
1180 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1181 {
1182 #if PACKET_DEBUG > 1
1183         static const char *state_name[] = {
1184                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1185         };
1186         enum packet_data_state old_state = pkt->state;
1187         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1188                 state_name[old_state], state_name[state]);
1189 #endif
1190         pkt->state = state;
1191 }
1192
1193 /*
1194  * Scan the work queue to see if we can start a new packet.
1195  * returns non-zero if any work was done.
1196  */
1197 static int pkt_handle_queue(struct pktcdvd_device *pd)
1198 {
1199         struct packet_data *pkt, *p;
1200         struct bio *bio = NULL;
1201         sector_t zone = 0; /* Suppress gcc warning */
1202         struct pkt_rb_node *node, *first_node;
1203         struct rb_node *n;
1204         int wakeup;
1205
1206         VPRINTK("handle_queue\n");
1207
1208         atomic_set(&pd->scan_queue, 0);
1209
1210         if (list_empty(&pd->cdrw.pkt_free_list)) {
1211                 VPRINTK("handle_queue: no pkt\n");
1212                 return 0;
1213         }
1214
1215         /*
1216          * Try to find a zone we are not already working on.
1217          */
1218         spin_lock(&pd->lock);
1219         first_node = pkt_rbtree_find(pd, pd->current_sector);
1220         if (!first_node) {
1221                 n = rb_first(&pd->bio_queue);
1222                 if (n)
1223                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1224         }
1225         node = first_node;
1226         while (node) {
1227                 bio = node->bio;
1228                 zone = ZONE(bio->bi_sector, pd);
1229                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1230                         if (p->sector == zone) {
1231                                 bio = NULL;
1232                                 goto try_next_bio;
1233                         }
1234                 }
1235                 break;
1236 try_next_bio:
1237                 node = pkt_rbtree_next(node);
1238                 if (!node) {
1239                         n = rb_first(&pd->bio_queue);
1240                         if (n)
1241                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
1242                 }
1243                 if (node == first_node)
1244                         node = NULL;
1245         }
1246         spin_unlock(&pd->lock);
1247         if (!bio) {
1248                 VPRINTK("handle_queue: no bio\n");
1249                 return 0;
1250         }
1251
1252         pkt = pkt_get_packet_data(pd, zone);
1253
1254         pd->current_sector = zone + pd->settings.size;
1255         pkt->sector = zone;
1256         BUG_ON(pkt->frames != pd->settings.size >> 2);
1257         pkt->write_size = 0;
1258
1259         /*
1260          * Scan work queue for bios in the same zone and link them
1261          * to this packet.
1262          */
1263         spin_lock(&pd->lock);
1264         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1265         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1266                 bio = node->bio;
1267                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
1268                         (unsigned long long)ZONE(bio->bi_sector, pd));
1269                 if (ZONE(bio->bi_sector, pd) != zone)
1270                         break;
1271                 pkt_rbtree_erase(pd, node);
1272                 spin_lock(&pkt->lock);
1273                 bio_list_add(&pkt->orig_bios, bio);
1274                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1275                 spin_unlock(&pkt->lock);
1276         }
1277         /* check write congestion marks, and if bio_queue_size is
1278            below, wake up any waiters */
1279         wakeup = (pd->write_congestion_on > 0
1280                         && pd->bio_queue_size <= pd->write_congestion_off);
1281         spin_unlock(&pd->lock);
1282         if (wakeup) {
1283                 clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1284                                         BLK_RW_ASYNC);
1285         }
1286
1287         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1288         pkt_set_state(pkt, PACKET_WAITING_STATE);
1289         atomic_set(&pkt->run_sm, 1);
1290
1291         spin_lock(&pd->cdrw.active_list_lock);
1292         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1293         spin_unlock(&pd->cdrw.active_list_lock);
1294
1295         return 1;
1296 }
1297
1298 /*
1299  * Assemble a bio to write one packet and queue the bio for processing
1300  * by the underlying block device.
1301  */
1302 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1303 {
1304         int f;
1305         struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1306
1307         bio_reset(pkt->w_bio);
1308         pkt->w_bio->bi_sector = pkt->sector;
1309         pkt->w_bio->bi_bdev = pd->bdev;
1310         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1311         pkt->w_bio->bi_private = pkt;
1312
1313         /* XXX: locking? */
1314         for (f = 0; f < pkt->frames; f++) {
1315                 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1316                 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1317                 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1318                         BUG();
1319         }
1320         VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1321
1322         /*
1323          * Fill-in bvec with data from orig_bios.
1324          */
1325         spin_lock(&pkt->lock);
1326         bio_copy_data(pkt->w_bio, pkt->orig_bios.head);
1327
1328         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1329         spin_unlock(&pkt->lock);
1330
1331         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1332                 pkt->write_size, (unsigned long long)pkt->sector);
1333
1334         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1335                 pkt_make_local_copy(pkt, bvec);
1336                 pkt->cache_valid = 1;
1337         } else {
1338                 pkt->cache_valid = 0;
1339         }
1340
1341         /* Start the write request */
1342         atomic_set(&pkt->io_wait, 1);
1343         pkt->w_bio->bi_rw = WRITE;
1344         pkt_queue_bio(pd, pkt->w_bio);
1345 }
1346
1347 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1348 {
1349         struct bio *bio;
1350
1351         if (!uptodate)
1352                 pkt->cache_valid = 0;
1353
1354         /* Finish all bios corresponding to this packet */
1355         while ((bio = bio_list_pop(&pkt->orig_bios)))
1356                 bio_endio(bio, uptodate ? 0 : -EIO);
1357 }
1358
1359 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1360 {
1361         int uptodate;
1362
1363         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1364
1365         for (;;) {
1366                 switch (pkt->state) {
1367                 case PACKET_WAITING_STATE:
1368                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1369                                 return;
1370
1371                         pkt->sleep_time = 0;
1372                         pkt_gather_data(pd, pkt);
1373                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1374                         break;
1375
1376                 case PACKET_READ_WAIT_STATE:
1377                         if (atomic_read(&pkt->io_wait) > 0)
1378                                 return;
1379
1380                         if (atomic_read(&pkt->io_errors) > 0) {
1381                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1382                         } else {
1383                                 pkt_start_write(pd, pkt);
1384                         }
1385                         break;
1386
1387                 case PACKET_WRITE_WAIT_STATE:
1388                         if (atomic_read(&pkt->io_wait) > 0)
1389                                 return;
1390
1391                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1392                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1393                         } else {
1394                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1395                         }
1396                         break;
1397
1398                 case PACKET_RECOVERY_STATE:
1399                         if (pkt_start_recovery(pkt)) {
1400                                 pkt_start_write(pd, pkt);
1401                         } else {
1402                                 VPRINTK("No recovery possible\n");
1403                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1404                         }
1405                         break;
1406
1407                 case PACKET_FINISHED_STATE:
1408                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1409                         pkt_finish_packet(pkt, uptodate);
1410                         return;
1411
1412                 default:
1413                         BUG();
1414                         break;
1415                 }
1416         }
1417 }
1418
1419 static void pkt_handle_packets(struct pktcdvd_device *pd)
1420 {
1421         struct packet_data *pkt, *next;
1422
1423         VPRINTK("pkt_handle_packets\n");
1424
1425         /*
1426          * Run state machine for active packets
1427          */
1428         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1429                 if (atomic_read(&pkt->run_sm) > 0) {
1430                         atomic_set(&pkt->run_sm, 0);
1431                         pkt_run_state_machine(pd, pkt);
1432                 }
1433         }
1434
1435         /*
1436          * Move no longer active packets to the free list
1437          */
1438         spin_lock(&pd->cdrw.active_list_lock);
1439         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1440                 if (pkt->state == PACKET_FINISHED_STATE) {
1441                         list_del(&pkt->list);
1442                         pkt_put_packet_data(pd, pkt);
1443                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1444                         atomic_set(&pd->scan_queue, 1);
1445                 }
1446         }
1447         spin_unlock(&pd->cdrw.active_list_lock);
1448 }
1449
1450 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1451 {
1452         struct packet_data *pkt;
1453         int i;
1454
1455         for (i = 0; i < PACKET_NUM_STATES; i++)
1456                 states[i] = 0;
1457
1458         spin_lock(&pd->cdrw.active_list_lock);
1459         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1460                 states[pkt->state]++;
1461         }
1462         spin_unlock(&pd->cdrw.active_list_lock);
1463 }
1464
1465 /*
1466  * kcdrwd is woken up when writes have been queued for one of our
1467  * registered devices
1468  */
1469 static int kcdrwd(void *foobar)
1470 {
1471         struct pktcdvd_device *pd = foobar;
1472         struct packet_data *pkt;
1473         long min_sleep_time, residue;
1474
1475         set_user_nice(current, -20);
1476         set_freezable();
1477
1478         for (;;) {
1479                 DECLARE_WAITQUEUE(wait, current);
1480
1481                 /*
1482                  * Wait until there is something to do
1483                  */
1484                 add_wait_queue(&pd->wqueue, &wait);
1485                 for (;;) {
1486                         set_current_state(TASK_INTERRUPTIBLE);
1487
1488                         /* Check if we need to run pkt_handle_queue */
1489                         if (atomic_read(&pd->scan_queue) > 0)
1490                                 goto work_to_do;
1491
1492                         /* Check if we need to run the state machine for some packet */
1493                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1494                                 if (atomic_read(&pkt->run_sm) > 0)
1495                                         goto work_to_do;
1496                         }
1497
1498                         /* Check if we need to process the iosched queues */
1499                         if (atomic_read(&pd->iosched.attention) != 0)
1500                                 goto work_to_do;
1501
1502                         /* Otherwise, go to sleep */
1503                         if (PACKET_DEBUG > 1) {
1504                                 int states[PACKET_NUM_STATES];
1505                                 pkt_count_states(pd, states);
1506                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1507                                         states[0], states[1], states[2], states[3],
1508                                         states[4], states[5]);
1509                         }
1510
1511                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1512                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1513                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1514                                         min_sleep_time = pkt->sleep_time;
1515                         }
1516
1517                         VPRINTK("kcdrwd: sleeping\n");
1518                         residue = schedule_timeout(min_sleep_time);
1519                         VPRINTK("kcdrwd: wake up\n");
1520
1521                         /* make swsusp happy with our thread */
1522                         try_to_freeze();
1523
1524                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1525                                 if (!pkt->sleep_time)
1526                                         continue;
1527                                 pkt->sleep_time -= min_sleep_time - residue;
1528                                 if (pkt->sleep_time <= 0) {
1529                                         pkt->sleep_time = 0;
1530                                         atomic_inc(&pkt->run_sm);
1531                                 }
1532                         }
1533
1534                         if (kthread_should_stop())
1535                                 break;
1536                 }
1537 work_to_do:
1538                 set_current_state(TASK_RUNNING);
1539                 remove_wait_queue(&pd->wqueue, &wait);
1540
1541                 if (kthread_should_stop())
1542                         break;
1543
1544                 /*
1545                  * if pkt_handle_queue returns true, we can queue
1546                  * another request.
1547                  */
1548                 while (pkt_handle_queue(pd))
1549                         ;
1550
1551                 /*
1552                  * Handle packet state machine
1553                  */
1554                 pkt_handle_packets(pd);
1555
1556                 /*
1557                  * Handle iosched queues
1558                  */
1559                 pkt_iosched_process_queue(pd);
1560         }
1561
1562         return 0;
1563 }
1564
1565 static void pkt_print_settings(struct pktcdvd_device *pd)
1566 {
1567         printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1568         printk("%u blocks, ", pd->settings.size >> 2);
1569         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1570 }
1571
1572 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1573 {
1574         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1575
1576         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1577         cgc->cmd[2] = page_code | (page_control << 6);
1578         cgc->cmd[7] = cgc->buflen >> 8;
1579         cgc->cmd[8] = cgc->buflen & 0xff;
1580         cgc->data_direction = CGC_DATA_READ;
1581         return pkt_generic_packet(pd, cgc);
1582 }
1583
1584 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1585 {
1586         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1587         memset(cgc->buffer, 0, 2);
1588         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1589         cgc->cmd[1] = 0x10;             /* PF */
1590         cgc->cmd[7] = cgc->buflen >> 8;
1591         cgc->cmd[8] = cgc->buflen & 0xff;
1592         cgc->data_direction = CGC_DATA_WRITE;
1593         return pkt_generic_packet(pd, cgc);
1594 }
1595
1596 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1597 {
1598         struct packet_command cgc;
1599         int ret;
1600
1601         /* set up command and get the disc info */
1602         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1603         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1604         cgc.cmd[8] = cgc.buflen = 2;
1605         cgc.quiet = 1;
1606
1607         if ((ret = pkt_generic_packet(pd, &cgc)))
1608                 return ret;
1609
1610         /* not all drives have the same disc_info length, so requeue
1611          * packet with the length the drive tells us it can supply
1612          */
1613         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1614                      sizeof(di->disc_information_length);
1615
1616         if (cgc.buflen > sizeof(disc_information))
1617                 cgc.buflen = sizeof(disc_information);
1618
1619         cgc.cmd[8] = cgc.buflen;
1620         return pkt_generic_packet(pd, &cgc);
1621 }
1622
1623 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1624 {
1625         struct packet_command cgc;
1626         int ret;
1627
1628         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1629         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1630         cgc.cmd[1] = type & 3;
1631         cgc.cmd[4] = (track & 0xff00) >> 8;
1632         cgc.cmd[5] = track & 0xff;
1633         cgc.cmd[8] = 8;
1634         cgc.quiet = 1;
1635
1636         if ((ret = pkt_generic_packet(pd, &cgc)))
1637                 return ret;
1638
1639         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1640                      sizeof(ti->track_information_length);
1641
1642         if (cgc.buflen > sizeof(track_information))
1643                 cgc.buflen = sizeof(track_information);
1644
1645         cgc.cmd[8] = cgc.buflen;
1646         return pkt_generic_packet(pd, &cgc);
1647 }
1648
1649 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1650                                                 long *last_written)
1651 {
1652         disc_information di;
1653         track_information ti;
1654         __u32 last_track;
1655         int ret = -1;
1656
1657         if ((ret = pkt_get_disc_info(pd, &di)))
1658                 return ret;
1659
1660         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1661         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1662                 return ret;
1663
1664         /* if this track is blank, try the previous. */
1665         if (ti.blank) {
1666                 last_track--;
1667                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1668                         return ret;
1669         }
1670
1671         /* if last recorded field is valid, return it. */
1672         if (ti.lra_v) {
1673                 *last_written = be32_to_cpu(ti.last_rec_address);
1674         } else {
1675                 /* make it up instead */
1676                 *last_written = be32_to_cpu(ti.track_start) +
1677                                 be32_to_cpu(ti.track_size);
1678                 if (ti.free_blocks)
1679                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1680         }
1681         return 0;
1682 }
1683
1684 /*
1685  * write mode select package based on pd->settings
1686  */
1687 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1688 {
1689         struct packet_command cgc;
1690         struct request_sense sense;
1691         write_param_page *wp;
1692         char buffer[128];
1693         int ret, size;
1694
1695         /* doesn't apply to DVD+RW or DVD-RAM */
1696         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1697                 return 0;
1698
1699         memset(buffer, 0, sizeof(buffer));
1700         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1701         cgc.sense = &sense;
1702         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1703                 pkt_dump_sense(&cgc);
1704                 return ret;
1705         }
1706
1707         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1708         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1709         if (size > sizeof(buffer))
1710                 size = sizeof(buffer);
1711
1712         /*
1713          * now get it all
1714          */
1715         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1716         cgc.sense = &sense;
1717         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1718                 pkt_dump_sense(&cgc);
1719                 return ret;
1720         }
1721
1722         /*
1723          * write page is offset header + block descriptor length
1724          */
1725         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1726
1727         wp->fp = pd->settings.fp;
1728         wp->track_mode = pd->settings.track_mode;
1729         wp->write_type = pd->settings.write_type;
1730         wp->data_block_type = pd->settings.block_mode;
1731
1732         wp->multi_session = 0;
1733
1734 #ifdef PACKET_USE_LS
1735         wp->link_size = 7;
1736         wp->ls_v = 1;
1737 #endif
1738
1739         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1740                 wp->session_format = 0;
1741                 wp->subhdr2 = 0x20;
1742         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1743                 wp->session_format = 0x20;
1744                 wp->subhdr2 = 8;
1745 #if 0
1746                 wp->mcn[0] = 0x80;
1747                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1748 #endif
1749         } else {
1750                 /*
1751                  * paranoia
1752                  */
1753                 printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1754                 return 1;
1755         }
1756         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1757
1758         cgc.buflen = cgc.cmd[8] = size;
1759         if ((ret = pkt_mode_select(pd, &cgc))) {
1760                 pkt_dump_sense(&cgc);
1761                 return ret;
1762         }
1763
1764         pkt_print_settings(pd);
1765         return 0;
1766 }
1767
1768 /*
1769  * 1 -- we can write to this track, 0 -- we can't
1770  */
1771 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1772 {
1773         switch (pd->mmc3_profile) {
1774                 case 0x1a: /* DVD+RW */
1775                 case 0x12: /* DVD-RAM */
1776                         /* The track is always writable on DVD+RW/DVD-RAM */
1777                         return 1;
1778                 default:
1779                         break;
1780         }
1781
1782         if (!ti->packet || !ti->fp)
1783                 return 0;
1784
1785         /*
1786          * "good" settings as per Mt Fuji.
1787          */
1788         if (ti->rt == 0 && ti->blank == 0)
1789                 return 1;
1790
1791         if (ti->rt == 0 && ti->blank == 1)
1792                 return 1;
1793
1794         if (ti->rt == 1 && ti->blank == 0)
1795                 return 1;
1796
1797         printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1798         return 0;
1799 }
1800
1801 /*
1802  * 1 -- we can write to this disc, 0 -- we can't
1803  */
1804 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1805 {
1806         switch (pd->mmc3_profile) {
1807                 case 0x0a: /* CD-RW */
1808                 case 0xffff: /* MMC3 not supported */
1809                         break;
1810                 case 0x1a: /* DVD+RW */
1811                 case 0x13: /* DVD-RW */
1812                 case 0x12: /* DVD-RAM */
1813                         return 1;
1814                 default:
1815                         VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1816                         return 0;
1817         }
1818
1819         /*
1820          * for disc type 0xff we should probably reserve a new track.
1821          * but i'm not sure, should we leave this to user apps? probably.
1822          */
1823         if (di->disc_type == 0xff) {
1824                 printk(DRIVER_NAME": Unknown disc. No track?\n");
1825                 return 0;
1826         }
1827
1828         if (di->disc_type != 0x20 && di->disc_type != 0) {
1829                 printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1830                 return 0;
1831         }
1832
1833         if (di->erasable == 0) {
1834                 printk(DRIVER_NAME": Disc not erasable\n");
1835                 return 0;
1836         }
1837
1838         if (di->border_status == PACKET_SESSION_RESERVED) {
1839                 printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1840                 return 0;
1841         }
1842
1843         return 1;
1844 }
1845
1846 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1847 {
1848         struct packet_command cgc;
1849         unsigned char buf[12];
1850         disc_information di;
1851         track_information ti;
1852         int ret, track;
1853
1854         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1855         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1856         cgc.cmd[8] = 8;
1857         ret = pkt_generic_packet(pd, &cgc);
1858         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1859
1860         memset(&di, 0, sizeof(disc_information));
1861         memset(&ti, 0, sizeof(track_information));
1862
1863         if ((ret = pkt_get_disc_info(pd, &di))) {
1864                 printk("failed get_disc\n");
1865                 return ret;
1866         }
1867
1868         if (!pkt_writable_disc(pd, &di))
1869                 return -EROFS;
1870
1871         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1872
1873         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1874         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1875                 printk(DRIVER_NAME": failed get_track\n");
1876                 return ret;
1877         }
1878
1879         if (!pkt_writable_track(pd, &ti)) {
1880                 printk(DRIVER_NAME": can't write to this track\n");
1881                 return -EROFS;
1882         }
1883
1884         /*
1885          * we keep packet size in 512 byte units, makes it easier to
1886          * deal with request calculations.
1887          */
1888         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1889         if (pd->settings.size == 0) {
1890                 printk(DRIVER_NAME": detected zero packet size!\n");
1891                 return -ENXIO;
1892         }
1893         if (pd->settings.size > PACKET_MAX_SECTORS) {
1894                 printk(DRIVER_NAME": packet size is too big\n");
1895                 return -EROFS;
1896         }
1897         pd->settings.fp = ti.fp;
1898         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1899
1900         if (ti.nwa_v) {
1901                 pd->nwa = be32_to_cpu(ti.next_writable);
1902                 set_bit(PACKET_NWA_VALID, &pd->flags);
1903         }
1904
1905         /*
1906          * in theory we could use lra on -RW media as well and just zero
1907          * blocks that haven't been written yet, but in practice that
1908          * is just a no-go. we'll use that for -R, naturally.
1909          */
1910         if (ti.lra_v) {
1911                 pd->lra = be32_to_cpu(ti.last_rec_address);
1912                 set_bit(PACKET_LRA_VALID, &pd->flags);
1913         } else {
1914                 pd->lra = 0xffffffff;
1915                 set_bit(PACKET_LRA_VALID, &pd->flags);
1916         }
1917
1918         /*
1919          * fine for now
1920          */
1921         pd->settings.link_loss = 7;
1922         pd->settings.write_type = 0;    /* packet */
1923         pd->settings.track_mode = ti.track_mode;
1924
1925         /*
1926          * mode1 or mode2 disc
1927          */
1928         switch (ti.data_mode) {
1929                 case PACKET_MODE1:
1930                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1931                         break;
1932                 case PACKET_MODE2:
1933                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1934                         break;
1935                 default:
1936                         printk(DRIVER_NAME": unknown data mode\n");
1937                         return -EROFS;
1938         }
1939         return 0;
1940 }
1941
1942 /*
1943  * enable/disable write caching on drive
1944  */
1945 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
1946                                                 int set)
1947 {
1948         struct packet_command cgc;
1949         struct request_sense sense;
1950         unsigned char buf[64];
1951         int ret;
1952
1953         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1954         cgc.sense = &sense;
1955         cgc.buflen = pd->mode_offset + 12;
1956
1957         /*
1958          * caching mode page might not be there, so quiet this command
1959          */
1960         cgc.quiet = 1;
1961
1962         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
1963                 return ret;
1964
1965         buf[pd->mode_offset + 10] |= (!!set << 2);
1966
1967         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
1968         ret = pkt_mode_select(pd, &cgc);
1969         if (ret) {
1970                 printk(DRIVER_NAME": write caching control failed\n");
1971                 pkt_dump_sense(&cgc);
1972         } else if (!ret && set)
1973                 printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
1974         return ret;
1975 }
1976
1977 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
1978 {
1979         struct packet_command cgc;
1980
1981         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
1982         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
1983         cgc.cmd[4] = lockflag ? 1 : 0;
1984         return pkt_generic_packet(pd, &cgc);
1985 }
1986
1987 /*
1988  * Returns drive maximum write speed
1989  */
1990 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
1991                                                 unsigned *write_speed)
1992 {
1993         struct packet_command cgc;
1994         struct request_sense sense;
1995         unsigned char buf[256+18];
1996         unsigned char *cap_buf;
1997         int ret, offset;
1998
1999         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
2000         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2001         cgc.sense = &sense;
2002
2003         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2004         if (ret) {
2005                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2006                              sizeof(struct mode_page_header);
2007                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2008                 if (ret) {
2009                         pkt_dump_sense(&cgc);
2010                         return ret;
2011                 }
2012         }
2013
2014         offset = 20;                        /* Obsoleted field, used by older drives */
2015         if (cap_buf[1] >= 28)
2016                 offset = 28;                /* Current write speed selected */
2017         if (cap_buf[1] >= 30) {
2018                 /* If the drive reports at least one "Logical Unit Write
2019                  * Speed Performance Descriptor Block", use the information
2020                  * in the first block. (contains the highest speed)
2021                  */
2022                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2023                 if (num_spdb > 0)
2024                         offset = 34;
2025         }
2026
2027         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2028         return 0;
2029 }
2030
2031 /* These tables from cdrecord - I don't have orange book */
2032 /* standard speed CD-RW (1-4x) */
2033 static char clv_to_speed[16] = {
2034         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2035            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2036 };
2037 /* high speed CD-RW (-10x) */
2038 static char hs_clv_to_speed[16] = {
2039         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2040            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2041 };
2042 /* ultra high speed CD-RW */
2043 static char us_clv_to_speed[16] = {
2044         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2045            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2046 };
2047
2048 /*
2049  * reads the maximum media speed from ATIP
2050  */
2051 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2052                                                 unsigned *speed)
2053 {
2054         struct packet_command cgc;
2055         struct request_sense sense;
2056         unsigned char buf[64];
2057         unsigned int size, st, sp;
2058         int ret;
2059
2060         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2061         cgc.sense = &sense;
2062         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2063         cgc.cmd[1] = 2;
2064         cgc.cmd[2] = 4; /* READ ATIP */
2065         cgc.cmd[8] = 2;
2066         ret = pkt_generic_packet(pd, &cgc);
2067         if (ret) {
2068                 pkt_dump_sense(&cgc);
2069                 return ret;
2070         }
2071         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2072         if (size > sizeof(buf))
2073                 size = sizeof(buf);
2074
2075         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2076         cgc.sense = &sense;
2077         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2078         cgc.cmd[1] = 2;
2079         cgc.cmd[2] = 4;
2080         cgc.cmd[8] = size;
2081         ret = pkt_generic_packet(pd, &cgc);
2082         if (ret) {
2083                 pkt_dump_sense(&cgc);
2084                 return ret;
2085         }
2086
2087         if (!(buf[6] & 0x40)) {
2088                 printk(DRIVER_NAME": Disc type is not CD-RW\n");
2089                 return 1;
2090         }
2091         if (!(buf[6] & 0x4)) {
2092                 printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2093                 return 1;
2094         }
2095
2096         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2097
2098         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2099
2100         /* Info from cdrecord */
2101         switch (st) {
2102                 case 0: /* standard speed */
2103                         *speed = clv_to_speed[sp];
2104                         break;
2105                 case 1: /* high speed */
2106                         *speed = hs_clv_to_speed[sp];
2107                         break;
2108                 case 2: /* ultra high speed */
2109                         *speed = us_clv_to_speed[sp];
2110                         break;
2111                 default:
2112                         printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2113                         return 1;
2114         }
2115         if (*speed) {
2116                 printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2117                 return 0;
2118         } else {
2119                 printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2120                 return 1;
2121         }
2122 }
2123
2124 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2125 {
2126         struct packet_command cgc;
2127         struct request_sense sense;
2128         int ret;
2129
2130         VPRINTK(DRIVER_NAME": Performing OPC\n");
2131
2132         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2133         cgc.sense = &sense;
2134         cgc.timeout = 60*HZ;
2135         cgc.cmd[0] = GPCMD_SEND_OPC;
2136         cgc.cmd[1] = 1;
2137         if ((ret = pkt_generic_packet(pd, &cgc)))
2138                 pkt_dump_sense(&cgc);
2139         return ret;
2140 }
2141
2142 static int pkt_open_write(struct pktcdvd_device *pd)
2143 {
2144         int ret;
2145         unsigned int write_speed, media_write_speed, read_speed;
2146
2147         if ((ret = pkt_probe_settings(pd))) {
2148                 VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2149                 return ret;
2150         }
2151
2152         if ((ret = pkt_set_write_settings(pd))) {
2153                 DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2154                 return -EIO;
2155         }
2156
2157         pkt_write_caching(pd, USE_WCACHING);
2158
2159         if ((ret = pkt_get_max_speed(pd, &write_speed)))
2160                 write_speed = 16 * 177;
2161         switch (pd->mmc3_profile) {
2162                 case 0x13: /* DVD-RW */
2163                 case 0x1a: /* DVD+RW */
2164                 case 0x12: /* DVD-RAM */
2165                         DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2166                         break;
2167                 default:
2168                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
2169                                 media_write_speed = 16;
2170                         write_speed = min(write_speed, media_write_speed * 177);
2171                         DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2172                         break;
2173         }
2174         read_speed = write_speed;
2175
2176         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2177                 DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2178                 return -EIO;
2179         }
2180         pd->write_speed = write_speed;
2181         pd->read_speed = read_speed;
2182
2183         if ((ret = pkt_perform_opc(pd))) {
2184                 DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2185         }
2186
2187         return 0;
2188 }
2189
2190 /*
2191  * called at open time.
2192  */
2193 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2194 {
2195         int ret;
2196         long lba;
2197         struct request_queue *q;
2198
2199         /*
2200          * We need to re-open the cdrom device without O_NONBLOCK to be able
2201          * to read/write from/to it. It is already opened in O_NONBLOCK mode
2202          * so bdget() can't fail.
2203          */
2204         bdget(pd->bdev->bd_dev);
2205         if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2206                 goto out;
2207
2208         if ((ret = pkt_get_last_written(pd, &lba))) {
2209                 printk(DRIVER_NAME": pkt_get_last_written failed\n");
2210                 goto out_putdev;
2211         }
2212
2213         set_capacity(pd->disk, lba << 2);
2214         set_capacity(pd->bdev->bd_disk, lba << 2);
2215         bd_set_size(pd->bdev, (loff_t)lba << 11);
2216
2217         q = bdev_get_queue(pd->bdev);
2218         if (write) {
2219                 if ((ret = pkt_open_write(pd)))
2220                         goto out_putdev;
2221                 /*
2222                  * Some CDRW drives can not handle writes larger than one packet,
2223                  * even if the size is a multiple of the packet size.
2224                  */
2225                 spin_lock_irq(q->queue_lock);
2226                 blk_queue_max_hw_sectors(q, pd->settings.size);
2227                 spin_unlock_irq(q->queue_lock);
2228                 set_bit(PACKET_WRITABLE, &pd->flags);
2229         } else {
2230                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2231                 clear_bit(PACKET_WRITABLE, &pd->flags);
2232         }
2233
2234         if ((ret = pkt_set_segment_merging(pd, q)))
2235                 goto out_putdev;
2236
2237         if (write) {
2238                 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2239                         printk(DRIVER_NAME": not enough memory for buffers\n");
2240                         ret = -ENOMEM;
2241                         goto out_putdev;
2242                 }
2243                 printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2244         }
2245
2246         return 0;
2247
2248 out_putdev:
2249         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2250 out:
2251         return ret;
2252 }
2253
2254 /*
2255  * called when the device is closed. makes sure that the device flushes
2256  * the internal cache before we close.
2257  */
2258 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2259 {
2260         if (flush && pkt_flush_cache(pd))
2261                 DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2262
2263         pkt_lock_door(pd, 0);
2264
2265         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2266         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2267
2268         pkt_shrink_pktlist(pd);
2269 }
2270
2271 static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2272 {
2273         if (dev_minor >= MAX_WRITERS)
2274                 return NULL;
2275         return pkt_devs[dev_minor];
2276 }
2277
2278 static int pkt_open(struct block_device *bdev, fmode_t mode)
2279 {
2280         struct pktcdvd_device *pd = NULL;
2281         int ret;
2282
2283         VPRINTK(DRIVER_NAME": entering open\n");
2284
2285         mutex_lock(&pktcdvd_mutex);
2286         mutex_lock(&ctl_mutex);
2287         pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2288         if (!pd) {
2289                 ret = -ENODEV;
2290                 goto out;
2291         }
2292         BUG_ON(pd->refcnt < 0);
2293
2294         pd->refcnt++;
2295         if (pd->refcnt > 1) {
2296                 if ((mode & FMODE_WRITE) &&
2297                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2298                         ret = -EBUSY;
2299                         goto out_dec;
2300                 }
2301         } else {
2302                 ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2303                 if (ret)
2304                         goto out_dec;
2305                 /*
2306                  * needed here as well, since ext2 (among others) may change
2307                  * the blocksize at mount time
2308                  */
2309                 set_blocksize(bdev, CD_FRAMESIZE);
2310         }
2311
2312         mutex_unlock(&ctl_mutex);
2313         mutex_unlock(&pktcdvd_mutex);
2314         return 0;
2315
2316 out_dec:
2317         pd->refcnt--;
2318 out:
2319         VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2320         mutex_unlock(&ctl_mutex);
2321         mutex_unlock(&pktcdvd_mutex);
2322         return ret;
2323 }
2324
2325 static int pkt_close(struct gendisk *disk, fmode_t mode)
2326 {
2327         struct pktcdvd_device *pd = disk->private_data;
2328         int ret = 0;
2329
2330         mutex_lock(&pktcdvd_mutex);
2331         mutex_lock(&ctl_mutex);
2332         pd->refcnt--;
2333         BUG_ON(pd->refcnt < 0);
2334         if (pd->refcnt == 0) {
2335                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2336                 pkt_release_dev(pd, flush);
2337         }
2338         mutex_unlock(&ctl_mutex);
2339         mutex_unlock(&pktcdvd_mutex);
2340         return ret;
2341 }
2342
2343
2344 static void pkt_end_io_read_cloned(struct bio *bio, int err,
2345                                    struct batch_complete *batch)
2346 {
2347         struct packet_stacked_data *psd = bio->bi_private;
2348         struct pktcdvd_device *pd = psd->pd;
2349
2350         bio_put(bio);
2351         bio_endio(psd->bio, err);
2352         mempool_free(psd, psd_pool);
2353         pkt_bio_finished(pd);
2354 }
2355
2356 static void pkt_make_request(struct request_queue *q, struct bio *bio)
2357 {
2358         struct pktcdvd_device *pd;
2359         char b[BDEVNAME_SIZE];
2360         sector_t zone;
2361         struct packet_data *pkt;
2362         int was_empty, blocked_bio;
2363         struct pkt_rb_node *node;
2364
2365         pd = q->queuedata;
2366         if (!pd) {
2367                 printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2368                 goto end_io;
2369         }
2370
2371         /*
2372          * Clone READ bios so we can have our own bi_end_io callback.
2373          */
2374         if (bio_data_dir(bio) == READ) {
2375                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2376                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2377
2378                 psd->pd = pd;
2379                 psd->bio = bio;
2380                 cloned_bio->bi_bdev = pd->bdev;
2381                 cloned_bio->bi_private = psd;
2382                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2383                 pd->stats.secs_r += bio_sectors(bio);
2384                 pkt_queue_bio(pd, cloned_bio);
2385                 return;
2386         }
2387
2388         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2389                 printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2390                         pd->name, (unsigned long long)bio->bi_sector);
2391                 goto end_io;
2392         }
2393
2394         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2395                 printk(DRIVER_NAME": wrong bio size\n");
2396                 goto end_io;
2397         }
2398
2399         blk_queue_bounce(q, &bio);
2400
2401         zone = ZONE(bio->bi_sector, pd);
2402         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2403                 (unsigned long long)bio->bi_sector,
2404                 (unsigned long long)bio_end_sector(bio));
2405
2406         /* Check if we have to split the bio */
2407         {
2408                 struct bio_pair *bp;
2409                 sector_t last_zone;
2410                 int first_sectors;
2411
2412                 last_zone = ZONE(bio_end_sector(bio) - 1, pd);
2413                 if (last_zone != zone) {
2414                         BUG_ON(last_zone != zone + pd->settings.size);
2415                         first_sectors = last_zone - bio->bi_sector;
2416                         bp = bio_split(bio, first_sectors);
2417                         BUG_ON(!bp);
2418                         pkt_make_request(q, &bp->bio1);
2419                         pkt_make_request(q, &bp->bio2);
2420                         bio_pair_release(bp);
2421                         return;
2422                 }
2423         }
2424
2425         /*
2426          * If we find a matching packet in state WAITING or READ_WAIT, we can
2427          * just append this bio to that packet.
2428          */
2429         spin_lock(&pd->cdrw.active_list_lock);
2430         blocked_bio = 0;
2431         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2432                 if (pkt->sector == zone) {
2433                         spin_lock(&pkt->lock);
2434                         if ((pkt->state == PACKET_WAITING_STATE) ||
2435                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2436                                 bio_list_add(&pkt->orig_bios, bio);
2437                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2438                                 if ((pkt->write_size >= pkt->frames) &&
2439                                     (pkt->state == PACKET_WAITING_STATE)) {
2440                                         atomic_inc(&pkt->run_sm);
2441                                         wake_up(&pd->wqueue);
2442                                 }
2443                                 spin_unlock(&pkt->lock);
2444                                 spin_unlock(&pd->cdrw.active_list_lock);
2445                                 return;
2446                         } else {
2447                                 blocked_bio = 1;
2448                         }
2449                         spin_unlock(&pkt->lock);
2450                 }
2451         }
2452         spin_unlock(&pd->cdrw.active_list_lock);
2453
2454         /*
2455          * Test if there is enough room left in the bio work queue
2456          * (queue size >= congestion on mark).
2457          * If not, wait till the work queue size is below the congestion off mark.
2458          */
2459         spin_lock(&pd->lock);
2460         if (pd->write_congestion_on > 0
2461             && pd->bio_queue_size >= pd->write_congestion_on) {
2462                 set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2463                 do {
2464                         spin_unlock(&pd->lock);
2465                         congestion_wait(BLK_RW_ASYNC, HZ);
2466                         spin_lock(&pd->lock);
2467                 } while(pd->bio_queue_size > pd->write_congestion_off);
2468         }
2469         spin_unlock(&pd->lock);
2470
2471         /*
2472          * No matching packet found. Store the bio in the work queue.
2473          */
2474         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2475         node->bio = bio;
2476         spin_lock(&pd->lock);
2477         BUG_ON(pd->bio_queue_size < 0);
2478         was_empty = (pd->bio_queue_size == 0);
2479         pkt_rbtree_insert(pd, node);
2480         spin_unlock(&pd->lock);
2481
2482         /*
2483          * Wake up the worker thread.
2484          */
2485         atomic_set(&pd->scan_queue, 1);
2486         if (was_empty) {
2487                 /* This wake_up is required for correct operation */
2488                 wake_up(&pd->wqueue);
2489         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2490                 /*
2491                  * This wake up is not required for correct operation,
2492                  * but improves performance in some cases.
2493                  */
2494                 wake_up(&pd->wqueue);
2495         }
2496         return;
2497 end_io:
2498         bio_io_error(bio);
2499 }
2500
2501
2502
2503 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2504                           struct bio_vec *bvec)
2505 {
2506         struct pktcdvd_device *pd = q->queuedata;
2507         sector_t zone = ZONE(bmd->bi_sector, pd);
2508         int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2509         int remaining = (pd->settings.size << 9) - used;
2510         int remaining2;
2511
2512         /*
2513          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2514          * boundary, pkt_make_request() will split the bio.
2515          */
2516         remaining2 = PAGE_SIZE - bmd->bi_size;
2517         remaining = max(remaining, remaining2);
2518
2519         BUG_ON(remaining < 0);
2520         return remaining;
2521 }
2522
2523 static void pkt_init_queue(struct pktcdvd_device *pd)
2524 {
2525         struct request_queue *q = pd->disk->queue;
2526
2527         blk_queue_make_request(q, pkt_make_request);
2528         blk_queue_logical_block_size(q, CD_FRAMESIZE);
2529         blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2530         blk_queue_merge_bvec(q, pkt_merge_bvec);
2531         q->queuedata = pd;
2532 }
2533
2534 static int pkt_seq_show(struct seq_file *m, void *p)
2535 {
2536         struct pktcdvd_device *pd = m->private;
2537         char *msg;
2538         char bdev_buf[BDEVNAME_SIZE];
2539         int states[PACKET_NUM_STATES];
2540
2541         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2542                    bdevname(pd->bdev, bdev_buf));
2543
2544         seq_printf(m, "\nSettings:\n");
2545         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2546
2547         if (pd->settings.write_type == 0)
2548                 msg = "Packet";
2549         else
2550                 msg = "Unknown";
2551         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2552
2553         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2554         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2555
2556         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2557
2558         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2559                 msg = "Mode 1";
2560         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2561                 msg = "Mode 2";
2562         else
2563                 msg = "Unknown";
2564         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2565
2566         seq_printf(m, "\nStatistics:\n");
2567         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2568         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2569         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2570         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2571         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2572
2573         seq_printf(m, "\nMisc:\n");
2574         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2575         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2576         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2577         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2578         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2579         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2580
2581         seq_printf(m, "\nQueue state:\n");
2582         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2583         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2584         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2585
2586         pkt_count_states(pd, states);
2587         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2588                    states[0], states[1], states[2], states[3], states[4], states[5]);
2589
2590         seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2591                         pd->write_congestion_off,
2592                         pd->write_congestion_on);
2593         return 0;
2594 }
2595
2596 static int pkt_seq_open(struct inode *inode, struct file *file)
2597 {
2598         return single_open(file, pkt_seq_show, PDE_DATA(inode));
2599 }
2600
2601 static const struct file_operations pkt_proc_fops = {
2602         .open   = pkt_seq_open,
2603         .read   = seq_read,
2604         .llseek = seq_lseek,
2605         .release = single_release
2606 };
2607
2608 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2609 {
2610         int i;
2611         int ret = 0;
2612         char b[BDEVNAME_SIZE];
2613         struct block_device *bdev;
2614
2615         if (pd->pkt_dev == dev) {
2616                 printk(DRIVER_NAME": Recursive setup not allowed\n");
2617                 return -EBUSY;
2618         }
2619         for (i = 0; i < MAX_WRITERS; i++) {
2620                 struct pktcdvd_device *pd2 = pkt_devs[i];
2621                 if (!pd2)
2622                         continue;
2623                 if (pd2->bdev->bd_dev == dev) {
2624                         printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
2625                         return -EBUSY;
2626                 }
2627                 if (pd2->pkt_dev == dev) {
2628                         printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2629                         return -EBUSY;
2630                 }
2631         }
2632
2633         bdev = bdget(dev);
2634         if (!bdev)
2635                 return -ENOMEM;
2636         ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2637         if (ret)
2638                 return ret;
2639
2640         /* This is safe, since we have a reference from open(). */
2641         __module_get(THIS_MODULE);
2642
2643         pd->bdev = bdev;
2644         set_blocksize(bdev, CD_FRAMESIZE);
2645
2646         pkt_init_queue(pd);
2647
2648         atomic_set(&pd->cdrw.pending_bios, 0);
2649         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2650         if (IS_ERR(pd->cdrw.thread)) {
2651                 printk(DRIVER_NAME": can't start kernel thread\n");
2652                 ret = -ENOMEM;
2653                 goto out_mem;
2654         }
2655
2656         proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2657         DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2658         return 0;
2659
2660 out_mem:
2661         blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2662         /* This is safe: open() is still holding a reference. */
2663         module_put(THIS_MODULE);
2664         return ret;
2665 }
2666
2667 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2668 {
2669         struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2670         int ret;
2671
2672         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2673                 MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2674
2675         mutex_lock(&pktcdvd_mutex);
2676         switch (cmd) {
2677         case CDROMEJECT:
2678                 /*
2679                  * The door gets locked when the device is opened, so we
2680                  * have to unlock it or else the eject command fails.
2681                  */
2682                 if (pd->refcnt == 1)
2683                         pkt_lock_door(pd, 0);
2684                 /* fallthru */
2685         /*
2686          * forward selected CDROM ioctls to CD-ROM, for UDF
2687          */
2688         case CDROMMULTISESSION:
2689         case CDROMREADTOCENTRY:
2690         case CDROM_LAST_WRITTEN:
2691         case CDROM_SEND_PACKET:
2692         case SCSI_IOCTL_SEND_COMMAND:
2693                 ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2694                 break;
2695
2696         default:
2697                 VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2698                 ret = -ENOTTY;
2699         }
2700         mutex_unlock(&pktcdvd_mutex);
2701
2702         return ret;
2703 }
2704
2705 static unsigned int pkt_check_events(struct gendisk *disk,
2706                                      unsigned int clearing)
2707 {
2708         struct pktcdvd_device *pd = disk->private_data;
2709         struct gendisk *attached_disk;
2710
2711         if (!pd)
2712                 return 0;
2713         if (!pd->bdev)
2714                 return 0;
2715         attached_disk = pd->bdev->bd_disk;
2716         if (!attached_disk || !attached_disk->fops->check_events)
2717                 return 0;
2718         return attached_disk->fops->check_events(attached_disk, clearing);
2719 }
2720
2721 static const struct block_device_operations pktcdvd_ops = {
2722         .owner =                THIS_MODULE,
2723         .open =                 pkt_open,
2724         .release =              pkt_close,
2725         .ioctl =                pkt_ioctl,
2726         .check_events =         pkt_check_events,
2727 };
2728
2729 static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
2730 {
2731         return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2732 }
2733
2734 /*
2735  * Set up mapping from pktcdvd device to CD-ROM device.
2736  */
2737 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2738 {
2739         int idx;
2740         int ret = -ENOMEM;
2741         struct pktcdvd_device *pd;
2742         struct gendisk *disk;
2743
2744         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2745
2746         for (idx = 0; idx < MAX_WRITERS; idx++)
2747                 if (!pkt_devs[idx])
2748                         break;
2749         if (idx == MAX_WRITERS) {
2750                 printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2751                 ret = -EBUSY;
2752                 goto out_mutex;
2753         }
2754
2755         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2756         if (!pd)
2757                 goto out_mutex;
2758
2759         pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2760                                                   sizeof(struct pkt_rb_node));
2761         if (!pd->rb_pool)
2762                 goto out_mem;
2763
2764         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2765         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2766         spin_lock_init(&pd->cdrw.active_list_lock);
2767
2768         spin_lock_init(&pd->lock);
2769         spin_lock_init(&pd->iosched.lock);
2770         bio_list_init(&pd->iosched.read_queue);
2771         bio_list_init(&pd->iosched.write_queue);
2772         sprintf(pd->name, DRIVER_NAME"%d", idx);
2773         init_waitqueue_head(&pd->wqueue);
2774         pd->bio_queue = RB_ROOT;
2775
2776         pd->write_congestion_on  = write_congestion_on;
2777         pd->write_congestion_off = write_congestion_off;
2778
2779         disk = alloc_disk(1);
2780         if (!disk)
2781                 goto out_mem;
2782         pd->disk = disk;
2783         disk->major = pktdev_major;
2784         disk->first_minor = idx;
2785         disk->fops = &pktcdvd_ops;
2786         disk->flags = GENHD_FL_REMOVABLE;
2787         strcpy(disk->disk_name, pd->name);
2788         disk->devnode = pktcdvd_devnode;
2789         disk->private_data = pd;
2790         disk->queue = blk_alloc_queue(GFP_KERNEL);
2791         if (!disk->queue)
2792                 goto out_mem2;
2793
2794         pd->pkt_dev = MKDEV(pktdev_major, idx);
2795         ret = pkt_new_dev(pd, dev);
2796         if (ret)
2797                 goto out_new_dev;
2798
2799         /* inherit events of the host device */
2800         disk->events = pd->bdev->bd_disk->events;
2801         disk->async_events = pd->bdev->bd_disk->async_events;
2802
2803         add_disk(disk);
2804
2805         pkt_sysfs_dev_new(pd);
2806         pkt_debugfs_dev_new(pd);
2807
2808         pkt_devs[idx] = pd;
2809         if (pkt_dev)
2810                 *pkt_dev = pd->pkt_dev;
2811
2812         mutex_unlock(&ctl_mutex);
2813         return 0;
2814
2815 out_new_dev:
2816         blk_cleanup_queue(disk->queue);
2817 out_mem2:
2818         put_disk(disk);
2819 out_mem:
2820         if (pd->rb_pool)
2821                 mempool_destroy(pd->rb_pool);
2822         kfree(pd);
2823 out_mutex:
2824         mutex_unlock(&ctl_mutex);
2825         printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2826         return ret;
2827 }
2828
2829 /*
2830  * Tear down mapping from pktcdvd device to CD-ROM device.
2831  */
2832 static int pkt_remove_dev(dev_t pkt_dev)
2833 {
2834         struct pktcdvd_device *pd;
2835         int idx;
2836         int ret = 0;
2837
2838         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2839
2840         for (idx = 0; idx < MAX_WRITERS; idx++) {
2841                 pd = pkt_devs[idx];
2842                 if (pd && (pd->pkt_dev == pkt_dev))
2843                         break;
2844         }
2845         if (idx == MAX_WRITERS) {
2846                 DPRINTK(DRIVER_NAME": dev not setup\n");
2847                 ret = -ENXIO;
2848                 goto out;
2849         }
2850
2851         if (pd->refcnt > 0) {
2852                 ret = -EBUSY;
2853                 goto out;
2854         }
2855         if (!IS_ERR(pd->cdrw.thread))
2856                 kthread_stop(pd->cdrw.thread);
2857
2858         pkt_devs[idx] = NULL;
2859
2860         pkt_debugfs_dev_remove(pd);
2861         pkt_sysfs_dev_remove(pd);
2862
2863         blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2864
2865         remove_proc_entry(pd->name, pkt_proc);
2866         DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2867
2868         del_gendisk(pd->disk);
2869         blk_cleanup_queue(pd->disk->queue);
2870         put_disk(pd->disk);
2871
2872         mempool_destroy(pd->rb_pool);
2873         kfree(pd);
2874
2875         /* This is safe: open() is still holding a reference. */
2876         module_put(THIS_MODULE);
2877
2878 out:
2879         mutex_unlock(&ctl_mutex);
2880         return ret;
2881 }
2882
2883 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2884 {
2885         struct pktcdvd_device *pd;
2886
2887         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2888
2889         pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2890         if (pd) {
2891                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2892                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2893         } else {
2894                 ctrl_cmd->dev = 0;
2895                 ctrl_cmd->pkt_dev = 0;
2896         }
2897         ctrl_cmd->num_devices = MAX_WRITERS;
2898
2899         mutex_unlock(&ctl_mutex);
2900 }
2901
2902 static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2903 {
2904         void __user *argp = (void __user *)arg;
2905         struct pkt_ctrl_command ctrl_cmd;
2906         int ret = 0;
2907         dev_t pkt_dev = 0;
2908
2909         if (cmd != PACKET_CTRL_CMD)
2910                 return -ENOTTY;
2911
2912         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2913                 return -EFAULT;
2914
2915         switch (ctrl_cmd.command) {
2916         case PKT_CTRL_CMD_SETUP:
2917                 if (!capable(CAP_SYS_ADMIN))
2918                         return -EPERM;
2919                 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2920                 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2921                 break;
2922         case PKT_CTRL_CMD_TEARDOWN:
2923                 if (!capable(CAP_SYS_ADMIN))
2924                         return -EPERM;
2925                 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2926                 break;
2927         case PKT_CTRL_CMD_STATUS:
2928                 pkt_get_status(&ctrl_cmd);
2929                 break;
2930         default:
2931                 return -ENOTTY;
2932         }
2933
2934         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2935                 return -EFAULT;
2936         return ret;
2937 }
2938
2939 #ifdef CONFIG_COMPAT
2940 static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2941 {
2942         return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2943 }
2944 #endif
2945
2946 static const struct file_operations pkt_ctl_fops = {
2947         .open           = nonseekable_open,
2948         .unlocked_ioctl = pkt_ctl_ioctl,
2949 #ifdef CONFIG_COMPAT
2950         .compat_ioctl   = pkt_ctl_compat_ioctl,
2951 #endif
2952         .owner          = THIS_MODULE,
2953         .llseek         = no_llseek,
2954 };
2955
2956 static struct miscdevice pkt_misc = {
2957         .minor          = MISC_DYNAMIC_MINOR,
2958         .name           = DRIVER_NAME,
2959         .nodename       = "pktcdvd/control",
2960         .fops           = &pkt_ctl_fops
2961 };
2962
2963 static int __init pkt_init(void)
2964 {
2965         int ret;
2966
2967         mutex_init(&ctl_mutex);
2968
2969         psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
2970                                         sizeof(struct packet_stacked_data));
2971         if (!psd_pool)
2972                 return -ENOMEM;
2973
2974         ret = register_blkdev(pktdev_major, DRIVER_NAME);
2975         if (ret < 0) {
2976                 printk(DRIVER_NAME": Unable to register block device\n");
2977                 goto out2;
2978         }
2979         if (!pktdev_major)
2980                 pktdev_major = ret;
2981
2982         ret = pkt_sysfs_init();
2983         if (ret)
2984                 goto out;
2985
2986         pkt_debugfs_init();
2987
2988         ret = misc_register(&pkt_misc);
2989         if (ret) {
2990                 printk(DRIVER_NAME": Unable to register misc device\n");
2991                 goto out_misc;
2992         }
2993
2994         pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
2995
2996         return 0;
2997
2998 out_misc:
2999         pkt_debugfs_cleanup();
3000         pkt_sysfs_cleanup();
3001 out:
3002         unregister_blkdev(pktdev_major, DRIVER_NAME);
3003 out2:
3004         mempool_destroy(psd_pool);
3005         return ret;
3006 }
3007
3008 static void __exit pkt_exit(void)
3009 {
3010         remove_proc_entry("driver/"DRIVER_NAME, NULL);
3011         misc_deregister(&pkt_misc);
3012
3013         pkt_debugfs_cleanup();
3014         pkt_sysfs_cleanup();
3015
3016         unregister_blkdev(pktdev_major, DRIVER_NAME);
3017         mempool_destroy(psd_pool);
3018 }
3019
3020 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3021 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3022 MODULE_LICENSE("GPL");
3023
3024 module_init(pkt_init);
3025 module_exit(pkt_exit);