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/kthread.h>
  52 #include <linux/errno.h>
  53 #include <linux/spinlock.h>
  54 #include <linux/file.h>
  55 #include <linux/proc_fs.h>
  56 #include <linux/seq_file.h>
  57 #include <linux/miscdevice.h>
  58 #include <linux/freezer.h>
  59 #include <linux/mutex.h>
  60 #include <scsi/scsi_cmnd.h>
  61 #include <scsi/scsi_ioctl.h>
  62 #include <scsi/scsi.h>
  63 #include <linux/debugfs.h>
  64 #include <linux/device.h>
  65
  66 #include <asm/uaccess.h>
  67
  68 #define DRIVER_NAME     "pktcdvd"
  69
  70 #if PACKET_DEBUG
  71 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  72 #else
  73 #define DPRINTK(fmt, args...)
  74 #endif
  75
  76 #if PACKET_DEBUG > 1
  77 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  78 #else
  79 #define VPRINTK(fmt, args...)
  80 #endif
  81
  82 #define MAX_SPEED 0xffff
  83
  84 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  85
  86 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  87 static struct proc_dir_entry *pkt_proc;
  88 static int pktdev_major;
  89 static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
  90 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
  91 static struct mutex ctl_mutex;  /* Serialize open/close/setup/teardown */
  92 static mempool_t *psd_pool;
  93
  94 static struct class     *class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
  95 static struct dentry    *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
  96
  97 /* forward declaration */
  98 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
  99 static int pkt_remove_dev(dev_t pkt_dev);
 100 static int pkt_seq_show(struct seq_file *m, void *p);
 101
 102
 103
 104 /*
 105  * create and register a pktcdvd kernel object.
 106  */
 107 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
 108                                         const char* name,
 109                                         struct kobject* parent,
 110                                         struct kobj_type* ktype)
 111 {
 112         struct pktcdvd_kobj *p;
 113         int error;
 114
 115         p = kzalloc(sizeof(*p), GFP_KERNEL);
 116         if (!p)
 117                 return NULL;
 118         p->pd = pd;
 119         error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
 120         if (error) {
 121                 kobject_put(&p->kobj);
 122                 return NULL;
 123         }
 124         kobject_uevent(&p->kobj, KOBJ_ADD);
 125         return p;
 126 }
 127 /*
 128  * remove a pktcdvd kernel object.
 129  */
 130 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 131 {
 132         if (p)
 133                 kobject_put(&p->kobj);
 134 }
 135 /*
 136  * default release function for pktcdvd kernel objects.
 137  */
 138 static void pkt_kobj_release(struct kobject *kobj)
 139 {
 140         kfree(to_pktcdvdkobj(kobj));
 141 }
 142
 143
 144 /**********************************************************
 145  *
 146  * sysfs interface for pktcdvd
 147  * by (C) 2006  Thomas Maier <balagi@justmail.de>
 148  *
 149  **********************************************************/
 150
 151 #define DEF_ATTR(_obj,_name,_mode) \
 152         static struct attribute _obj = { .name = _name, .mode = _mode }
 153
 154 /**********************************************************
 155   /sys/class/pktcdvd/pktcdvd[0-7]/
 156                      stat/reset
 157                      stat/packets_started
 158                      stat/packets_finished
 159                      stat/kb_written
 160                      stat/kb_read
 161                      stat/kb_read_gather
 162                      write_queue/size
 163                      write_queue/congestion_off
 164                      write_queue/congestion_on
 165  **********************************************************/
 166
 167 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 168 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 169 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 170 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 171 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 172 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 173
 174 static struct attribute *kobj_pkt_attrs_stat[] = {
 175         &kobj_pkt_attr_st1,
 176         &kobj_pkt_attr_st2,
 177         &kobj_pkt_attr_st3,
 178         &kobj_pkt_attr_st4,
 179         &kobj_pkt_attr_st5,
 180         &kobj_pkt_attr_st6,
 181         NULL
 182 };
 183
 184 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 185 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 186 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 187
 188 static struct attribute *kobj_pkt_attrs_wqueue[] = {
 189         &kobj_pkt_attr_wq1,
 190         &kobj_pkt_attr_wq2,
 191         &kobj_pkt_attr_wq3,
 192         NULL
 193 };
 194
 195 static ssize_t kobj_pkt_show(struct kobject *kobj,
 196                         struct attribute *attr, char *data)
 197 {
 198         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 199         int n = 0;
 200         int v;
 201         if (strcmp(attr->name, "packets_started") == 0) {
 202                 n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 203
 204         } else if (strcmp(attr->name, "packets_finished") == 0) {
 205                 n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 206
 207         } else if (strcmp(attr->name, "kb_written") == 0) {
 208                 n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 209
 210         } else if (strcmp(attr->name, "kb_read") == 0) {
 211                 n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 212
 213         } else if (strcmp(attr->name, "kb_read_gather") == 0) {
 214                 n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 215
 216         } else if (strcmp(attr->name, "size") == 0) {
 217                 spin_lock(&pd->lock);
 218                 v = pd->bio_queue_size;
 219                 spin_unlock(&pd->lock);
 220                 n = sprintf(data, "%d\n", v);
 221
 222         } else if (strcmp(attr->name, "congestion_off") == 0) {
 223                 spin_lock(&pd->lock);
 224                 v = pd->write_congestion_off;
 225                 spin_unlock(&pd->lock);
 226                 n = sprintf(data, "%d\n", v);
 227
 228         } else if (strcmp(attr->name, "congestion_on") == 0) {
 229                 spin_lock(&pd->lock);
 230                 v = pd->write_congestion_on;
 231                 spin_unlock(&pd->lock);
 232                 n = sprintf(data, "%d\n", v);
 233         }
 234         return n;
 235 }
 236
 237 static void init_write_congestion_marks(int* lo, int* hi)
 238 {
 239         if (*hi > 0) {
 240                 *hi = max(*hi, 500);
 241                 *hi = min(*hi, 1000000);
 242                 if (*lo <= 0)
 243                         *lo = *hi - 100;
 244                 else {
 245                         *lo = min(*lo, *hi - 100);
 246                         *lo = max(*lo, 100);
 247                 }
 248         } else {
 249                 *hi = -1;
 250                 *lo = -1;
 251         }
 252 }
 253
 254 static ssize_t kobj_pkt_store(struct kobject *kobj,
 255                         struct attribute *attr,
 256                         const char *data, size_t len)
 257 {
 258         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 259         int val;
 260
 261         if (strcmp(attr->name, "reset") == 0 && len > 0) {
 262                 pd->stats.pkt_started = 0;
 263                 pd->stats.pkt_ended = 0;
 264                 pd->stats.secs_w = 0;
 265                 pd->stats.secs_rg = 0;
 266                 pd->stats.secs_r = 0;
 267
 268         } else if (strcmp(attr->name, "congestion_off") == 0
 269                    && sscanf(data, "%d", &val) == 1) {
 270                 spin_lock(&pd->lock);
 271                 pd->write_congestion_off = val;
 272                 init_write_congestion_marks(&pd->write_congestion_off,
 273                                         &pd->write_congestion_on);
 274                 spin_unlock(&pd->lock);
 275
 276         } else if (strcmp(attr->name, "congestion_on") == 0
 277                    && sscanf(data, "%d", &val) == 1) {
 278                 spin_lock(&pd->lock);
 279                 pd->write_congestion_on = val;
 280                 init_write_congestion_marks(&pd->write_congestion_off,
 281                                         &pd->write_congestion_on);
 282                 spin_unlock(&pd->lock);
 283         }
 284         return len;
 285 }
 286
 287 static const struct sysfs_ops kobj_pkt_ops = {
 288         .show = kobj_pkt_show,
 289         .store = kobj_pkt_store
 290 };
 291 static struct kobj_type kobj_pkt_type_stat = {
 292         .release = pkt_kobj_release,
 293         .sysfs_ops = &kobj_pkt_ops,
 294         .default_attrs = kobj_pkt_attrs_stat
 295 };
 296 static struct kobj_type kobj_pkt_type_wqueue = {
 297         .release = pkt_kobj_release,
 298         .sysfs_ops = &kobj_pkt_ops,
 299         .default_attrs = kobj_pkt_attrs_wqueue
 300 };
 301
 302 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 303 {
 304         if (class_pktcdvd) {
 305                 pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
 306                                         "%s", pd->name);
 307                 if (IS_ERR(pd->dev))
 308                         pd->dev = NULL;
 309         }
 310         if (pd->dev) {
 311                 pd->kobj_stat = pkt_kobj_create(pd, "stat",
 312                                         &pd->dev->kobj,
 313                                         &kobj_pkt_type_stat);
 314                 pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 315                                         &pd->dev->kobj,
 316                                         &kobj_pkt_type_wqueue);
 317         }
 318 }
 319
 320 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 321 {
 322         pkt_kobj_remove(pd->kobj_stat);
 323         pkt_kobj_remove(pd->kobj_wqueue);
 324         if (class_pktcdvd)
 325                 device_unregister(pd->dev);
 326 }
 327
 328
 329 /********************************************************************
 330   /sys/class/pktcdvd/
 331                      add            map block device
 332                      remove         unmap packet dev
 333                      device_map     show mappings
 334  *******************************************************************/
 335
 336 static void class_pktcdvd_release(struct class *cls)
 337 {
 338         kfree(cls);
 339 }
 340 static ssize_t class_pktcdvd_show_map(struct class *c,
 341                                         struct class_attribute *attr,
 342                                         char *data)
 343 {
 344         int n = 0;
 345         int idx;
 346         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 347         for (idx = 0; idx < MAX_WRITERS; idx++) {
 348                 struct pktcdvd_device *pd = pkt_devs[idx];
 349                 if (!pd)
 350                         continue;
 351                 n += sprintf(data+n, "%s %u:%u %u:%u\n",
 352                         pd->name,
 353                         MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 354                         MAJOR(pd->bdev->bd_dev),
 355                         MINOR(pd->bdev->bd_dev));
 356         }
 357         mutex_unlock(&ctl_mutex);
 358         return n;
 359 }
 360
 361 static ssize_t class_pktcdvd_store_add(struct class *c,
 362                                         struct class_attribute *attr,
 363                                         const char *buf,
 364                                         size_t count)
 365 {
 366         unsigned int major, minor;
 367
 368         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 369                 /* pkt_setup_dev() expects caller to hold reference to self */
 370                 if (!try_module_get(THIS_MODULE))
 371                         return -ENODEV;
 372
 373                 pkt_setup_dev(MKDEV(major, minor), NULL);
 374
 375                 module_put(THIS_MODULE);
 376
 377                 return count;
 378         }
 379
 380         return -EINVAL;
 381 }
 382
 383 static ssize_t class_pktcdvd_store_remove(struct class *c,
 384                                           struct class_attribute *attr,
 385                                           const char *buf,
 386                                         size_t count)
 387 {
 388         unsigned int major, minor;
 389         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 390                 pkt_remove_dev(MKDEV(major, minor));
 391                 return count;
 392         }
 393         return -EINVAL;
 394 }
 395
 396 static struct class_attribute class_pktcdvd_attrs[] = {
 397  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 398  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 399  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 400  __ATTR_NULL
 401 };
 402
 403
 404 static int pkt_sysfs_init(void)
 405 {
 406         int ret = 0;
 407
 408         /*
 409          * create control files in sysfs
 410          * /sys/class/pktcdvd/...
 411          */
 412         class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 413         if (!class_pktcdvd)
 414                 return -ENOMEM;
 415         class_pktcdvd->name = DRIVER_NAME;
 416         class_pktcdvd->owner = THIS_MODULE;
 417         class_pktcdvd->class_release = class_pktcdvd_release;
 418         class_pktcdvd->class_attrs = class_pktcdvd_attrs;
 419         ret = class_register(class_pktcdvd);
 420         if (ret) {
 421                 kfree(class_pktcdvd);
 422                 class_pktcdvd = NULL;
 423                 printk(DRIVER_NAME": failed to create class pktcdvd\n");
 424                 return ret;
 425         }
 426         return 0;
 427 }
 428
 429 static void pkt_sysfs_cleanup(void)
 430 {
 431         if (class_pktcdvd)
 432                 class_destroy(class_pktcdvd);
 433         class_pktcdvd = NULL;
 434 }
 435
 436 /********************************************************************
 437   entries in debugfs
 438
 439   /sys/kernel/debug/pktcdvd[0-7]/
 440                         info
 441
 442  *******************************************************************/
 443
 444 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 445 {
 446         return pkt_seq_show(m, p);
 447 }
 448
 449 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 450 {
 451         return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 452 }
 453
 454 static const struct file_operations debug_fops = {
 455         .open           = pkt_debugfs_fops_open,
 456         .read           = seq_read,
 457         .llseek         = seq_lseek,
 458         .release        = single_release,
 459         .owner          = THIS_MODULE,
 460 };
 461
 462 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 463 {
 464         if (!pkt_debugfs_root)
 465                 return;
 466         pd->dfs_f_info = NULL;
 467         pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 468         if (IS_ERR(pd->dfs_d_root)) {
 469                 pd->dfs_d_root = NULL;
 470                 return;
 471         }
 472         pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
 473                                 pd->dfs_d_root, pd, &debug_fops);
 474         if (IS_ERR(pd->dfs_f_info)) {
 475                 pd->dfs_f_info = NULL;
 476                 return;
 477         }
 478 }
 479
 480 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 481 {
 482         if (!pkt_debugfs_root)
 483                 return;
 484         if (pd->dfs_f_info)
 485                 debugfs_remove(pd->dfs_f_info);
 486         pd->dfs_f_info = NULL;
 487         if (pd->dfs_d_root)
 488                 debugfs_remove(pd->dfs_d_root);
 489         pd->dfs_d_root = NULL;
 490 }
 491
 492 static void pkt_debugfs_init(void)
 493 {
 494         pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 495         if (IS_ERR(pkt_debugfs_root)) {
 496                 pkt_debugfs_root = NULL;
 497                 return;
 498         }
 499 }
 500
 501 static void pkt_debugfs_cleanup(void)
 502 {
 503         if (!pkt_debugfs_root)
 504                 return;
 505         debugfs_remove(pkt_debugfs_root);
 506         pkt_debugfs_root = NULL;
 507 }
 508
 509 /* ----------------------------------------------------------*/
 510
 511
 512 static void pkt_bio_finished(struct pktcdvd_device *pd)
 513 {
 514         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 515         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 516                 VPRINTK(DRIVER_NAME": queue empty\n");
 517                 atomic_set(&pd->iosched.attention, 1);
 518                 wake_up(&pd->wqueue);
 519         }
 520 }
 521
 522 static void pkt_bio_destructor(struct bio *bio)
 523 {
 524         kfree(bio->bi_io_vec);
 525         kfree(bio);
 526 }
 527
 528 static struct bio *pkt_bio_alloc(int nr_iovecs)
 529 {
 530         struct bio_vec *bvl = NULL;
 531         struct bio *bio;
 532
 533         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
 534         if (!bio)
 535                 goto no_bio;
 536         bio_init(bio);
 537
 538         bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL);
 539         if (!bvl)
 540                 goto no_bvl;
 541
 542         bio->bi_max_vecs = nr_iovecs;
 543         bio->bi_io_vec = bvl;
 544         bio->bi_destructor = pkt_bio_destructor;
 545
 546         return bio;
 547
 548  no_bvl:
 549         kfree(bio);
 550  no_bio:
 551         return NULL;
 552 }
 553
 554 /*
 555  * Allocate a packet_data struct
 556  */
 557 static struct packet_data *pkt_alloc_packet_data(int frames)
 558 {
 559         int i;
 560         struct packet_data *pkt;
 561
 562         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 563         if (!pkt)
 564                 goto no_pkt;
 565
 566         pkt->frames = frames;
 567         pkt->w_bio = pkt_bio_alloc(frames);
 568         if (!pkt->w_bio)
 569                 goto no_bio;
 570
 571         for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 572                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 573                 if (!pkt->pages[i])
 574                         goto no_page;
 575         }
 576
 577         spin_lock_init(&pkt->lock);
 578         bio_list_init(&pkt->orig_bios);
 579
 580         for (i = 0; i < frames; i++) {
 581                 struct bio *bio = pkt_bio_alloc(1);
 582                 if (!bio)
 583                         goto no_rd_bio;
 584                 pkt->r_bios[i] = bio;
 585         }
 586
 587         return pkt;
 588
 589 no_rd_bio:
 590         for (i = 0; i < frames; i++) {
 591                 struct bio *bio = pkt->r_bios[i];
 592                 if (bio)
 593                         bio_put(bio);
 594         }
 595
 596 no_page:
 597         for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 598                 if (pkt->pages[i])
 599                         __free_page(pkt->pages[i]);
 600         bio_put(pkt->w_bio);
 601 no_bio:
 602         kfree(pkt);
 603 no_pkt:
 604         return NULL;
 605 }
 606
 607 /*
 608  * Free a packet_data struct
 609  */
 610 static void pkt_free_packet_data(struct packet_data *pkt)
 611 {
 612         int i;
 613
 614         for (i = 0; i < pkt->frames; i++) {
 615                 struct bio *bio = pkt->r_bios[i];
 616                 if (bio)
 617                         bio_put(bio);
 618         }
 619         for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 620                 __free_page(pkt->pages[i]);
 621         bio_put(pkt->w_bio);
 622         kfree(pkt);
 623 }
 624
 625 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 626 {
 627         struct packet_data *pkt, *next;
 628
 629         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 630
 631         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 632                 pkt_free_packet_data(pkt);
 633         }
 634         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 635 }
 636
 637 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 638 {
 639         struct packet_data *pkt;
 640
 641         BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 642
 643         while (nr_packets > 0) {
 644                 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 645                 if (!pkt) {
 646                         pkt_shrink_pktlist(pd);
 647                         return 0;
 648                 }
 649                 pkt->id = nr_packets;
 650                 pkt->pd = pd;
 651                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 652                 nr_packets--;
 653         }
 654         return 1;
 655 }
 656
 657 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 658 {
 659         struct rb_node *n = rb_next(&node->rb_node);
 660         if (!n)
 661                 return NULL;
 662         return rb_entry(n, struct pkt_rb_node, rb_node);
 663 }
 664
 665 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 666 {
 667         rb_erase(&node->rb_node, &pd->bio_queue);
 668         mempool_free(node, pd->rb_pool);
 669         pd->bio_queue_size--;
 670         BUG_ON(pd->bio_queue_size < 0);
 671 }
 672
 673 /*
 674  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 675  */
 676 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 677 {
 678         struct rb_node *n = pd->bio_queue.rb_node;
 679         struct rb_node *next;
 680         struct pkt_rb_node *tmp;
 681
 682         if (!n) {
 683                 BUG_ON(pd->bio_queue_size > 0);
 684                 return NULL;
 685         }
 686
 687         for (;;) {
 688                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 689                 if (s <= tmp->bio->bi_sector)
 690                         next = n->rb_left;
 691                 else
 692                         next = n->rb_right;
 693                 if (!next)
 694                         break;
 695                 n = next;
 696         }
 697
 698         if (s > tmp->bio->bi_sector) {
 699                 tmp = pkt_rbtree_next(tmp);
 700                 if (!tmp)
 701                         return NULL;
 702         }
 703         BUG_ON(s > tmp->bio->bi_sector);
 704         return tmp;
 705 }
 706
 707 /*
 708  * Insert a node into the pd->bio_queue rb tree.
 709  */
 710 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 711 {
 712         struct rb_node **p = &pd->bio_queue.rb_node;
 713         struct rb_node *parent = NULL;
 714         sector_t s = node->bio->bi_sector;
 715         struct pkt_rb_node *tmp;
 716
 717         while (*p) {
 718                 parent = *p;
 719                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 720                 if (s < tmp->bio->bi_sector)
 721                         p = &(*p)->rb_left;
 722                 else
 723                         p = &(*p)->rb_right;
 724         }
 725         rb_link_node(&node->rb_node, parent, p);
 726         rb_insert_color(&node->rb_node, &pd->bio_queue);
 727         pd->bio_queue_size++;
 728 }
 729
 730 /*
 731  * Send a packet_command to the underlying block device and
 732  * wait for completion.
 733  */
 734 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 735 {
 736         struct request_queue *q = bdev_get_queue(pd->bdev);
 737         struct request *rq;
 738         int ret = 0;
 739
 740         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 741                              WRITE : READ, __GFP_WAIT);
 742
 743         if (cgc->buflen) {
 744                 if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
 745                         goto out;
 746         }
 747
 748         rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 749         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 750
 751         rq->timeout = 60*HZ;
 752         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 753         rq->cmd_flags |= REQ_HARDBARRIER;
 754         if (cgc->quiet)
 755                 rq->cmd_flags |= REQ_QUIET;
 756
 757         blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 758         if (rq->errors)
 759                 ret = -EIO;
 760 out:
 761         blk_put_request(rq);
 762         return ret;
 763 }
 764
 765 /*
 766  * A generic sense dump / resolve mechanism should be implemented across
 767  * all ATAPI + SCSI devices.
 768  */
 769 static void pkt_dump_sense(struct packet_command *cgc)
 770 {
 771         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 772                                  "Medium error", "Hardware error", "Illegal request",
 773                                  "Unit attention", "Data protect", "Blank check" };
 774         int i;
 775         struct request_sense *sense = cgc->sense;
 776
 777         printk(DRIVER_NAME":");
 778         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 779                 printk(" %02x", cgc->cmd[i]);
 780         printk(" - ");
 781
 782         if (sense == NULL) {
 783                 printk("no sense\n");
 784                 return;
 785         }
 786
 787         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 788
 789         if (sense->sense_key > 8) {
 790                 printk(" (INVALID)\n");
 791                 return;
 792         }
 793
 794         printk(" (%s)\n", info[sense->sense_key]);
 795 }
 796
 797 /*
 798  * flush the drive cache to media
 799  */
 800 static int pkt_flush_cache(struct pktcdvd_device *pd)
 801 {
 802         struct packet_command cgc;
 803
 804         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 805         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 806         cgc.quiet = 1;
 807
 808         /*
 809          * the IMMED bit -- we default to not setting it, although that
 810          * would allow a much faster close, this is safer
 811          */
 812 #if 0
 813         cgc.cmd[1] = 1 << 1;
 814 #endif
 815         return pkt_generic_packet(pd, &cgc);
 816 }
 817
 818 /*
 819  * speed is given as the normal factor, e.g. 4 for 4x
 820  */
 821 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 822                                 unsigned write_speed, unsigned read_speed)
 823 {
 824         struct packet_command cgc;
 825         struct request_sense sense;
 826         int ret;
 827
 828         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 829         cgc.sense = &sense;
 830         cgc.cmd[0] = GPCMD_SET_SPEED;
 831         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 832         cgc.cmd[3] = read_speed & 0xff;
 833         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 834         cgc.cmd[5] = write_speed & 0xff;
 835
 836         if ((ret = pkt_generic_packet(pd, &cgc)))
 837                 pkt_dump_sense(&cgc);
 838
 839         return ret;
 840 }
 841
 842 /*
 843  * Queue a bio for processing by the low-level CD device. Must be called
 844  * from process context.
 845  */
 846 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 847 {
 848         spin_lock(&pd->iosched.lock);
 849         if (bio_data_dir(bio) == READ)
 850                 bio_list_add(&pd->iosched.read_queue, bio);
 851         else
 852                 bio_list_add(&pd->iosched.write_queue, bio);
 853         spin_unlock(&pd->iosched.lock);
 854
 855         atomic_set(&pd->iosched.attention, 1);
 856         wake_up(&pd->wqueue);
 857 }
 858
 859 /*
 860  * Process the queued read/write requests. This function handles special
 861  * requirements for CDRW drives:
 862  * - A cache flush command must be inserted before a read request if the
 863  *   previous request was a write.
 864  * - Switching between reading and writing is slow, so don't do it more often
 865  *   than necessary.
 866  * - Optimize for throughput at the expense of latency. This means that streaming
 867  *   writes will never be interrupted by a read, but if the drive has to seek
 868  *   before the next write, switch to reading instead if there are any pending
 869  *   read requests.
 870  * - Set the read speed according to current usage pattern. When only reading
 871  *   from the device, it's best to use the highest possible read speed, but
 872  *   when switching often between reading and writing, it's better to have the
 873  *   same read and write speeds.
 874  */
 875 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 876 {
 877
 878         if (atomic_read(&pd->iosched.attention) == 0)
 879                 return;
 880         atomic_set(&pd->iosched.attention, 0);
 881
 882         for (;;) {
 883                 struct bio *bio;
 884                 int reads_queued, writes_queued;
 885
 886                 spin_lock(&pd->iosched.lock);
 887                 reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 888                 writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 889                 spin_unlock(&pd->iosched.lock);
 890
 891                 if (!reads_queued && !writes_queued)
 892                         break;
 893
 894                 if (pd->iosched.writing) {
 895                         int need_write_seek = 1;
 896                         spin_lock(&pd->iosched.lock);
 897                         bio = bio_list_peek(&pd->iosched.write_queue);
 898                         spin_unlock(&pd->iosched.lock);
 899                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 900                                 need_write_seek = 0;
 901                         if (need_write_seek && reads_queued) {
 902                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 903                                         VPRINTK(DRIVER_NAME": write, waiting\n");
 904                                         break;
 905                                 }
 906                                 pkt_flush_cache(pd);
 907                                 pd->iosched.writing = 0;
 908                         }
 909                 } else {
 910                         if (!reads_queued && writes_queued) {
 911                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 912                                         VPRINTK(DRIVER_NAME": read, waiting\n");
 913                                         break;
 914                                 }
 915                                 pd->iosched.writing = 1;
 916                         }
 917                 }
 918
 919                 spin_lock(&pd->iosched.lock);
 920                 if (pd->iosched.writing)
 921                         bio = bio_list_pop(&pd->iosched.write_queue);
 922                 else
 923                         bio = bio_list_pop(&pd->iosched.read_queue);
 924                 spin_unlock(&pd->iosched.lock);
 925
 926                 if (!bio)
 927                         continue;
 928
 929                 if (bio_data_dir(bio) == READ)
 930                         pd->iosched.successive_reads += bio->bi_size >> 10;
 931                 else {
 932                         pd->iosched.successive_reads = 0;
 933                         pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
 934                 }
 935                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 936                         if (pd->read_speed == pd->write_speed) {
 937                                 pd->read_speed = MAX_SPEED;
 938                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 939                         }
 940                 } else {
 941                         if (pd->read_speed != pd->write_speed) {
 942                                 pd->read_speed = pd->write_speed;
 943                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 944                         }
 945                 }
 946
 947                 atomic_inc(&pd->cdrw.pending_bios);
 948                 generic_make_request(bio);
 949         }
 950 }
 951
 952 /*
 953  * Special care is needed if the underlying block device has a small
 954  * max_phys_segments value.
 955  */
 956 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 957 {
 958         if ((pd->settings.size << 9) / CD_FRAMESIZE
 959             <= queue_max_segments(q)) {
 960                 /*
 961                  * The cdrom device can handle one segment/frame
 962                  */
 963                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 964                 return 0;
 965         } else if ((pd->settings.size << 9) / PAGE_SIZE
 966                    <= queue_max_segments(q)) {
 967                 /*
 968                  * We can handle this case at the expense of some extra memory
 969                  * copies during write operations
 970                  */
 971                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 972                 return 0;
 973         } else {
 974                 printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
 975                 return -EIO;
 976         }
 977 }
 978
 979 /*
 980  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 981  */
 982 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 983 {
 984         unsigned int copy_size = CD_FRAMESIZE;
 985
 986         while (copy_size > 0) {
 987                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 988                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
 989                         src_bvl->bv_offset + offs;
 990                 void *vto = page_address(dst_page) + dst_offs;
 991                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 992
 993                 BUG_ON(len < 0);
 994                 memcpy(vto, vfrom, len);
 995                 kunmap_atomic(vfrom, KM_USER0);
 996
 997                 seg++;
 998                 offs = 0;
 999                 dst_offs += len;
1000                 copy_size -= len;
1001         }
1002 }
1003
1004 /*
1005  * Copy all data for this packet to pkt->pages[], so that
1006  * a) The number of required segments for the write bio is minimized, which
1007  *    is necessary for some scsi controllers.
1008  * b) The data can be used as cache to avoid read requests if we receive a
1009  *    new write request for the same zone.
1010  */
1011 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
1012 {
1013         int f, p, offs;
1014
1015         /* Copy all data to pkt->pages[] */
1016         p = 0;
1017         offs = 0;
1018         for (f = 0; f < pkt->frames; f++) {
1019                 if (bvec[f].bv_page != pkt->pages[p]) {
1020                         void *vfrom = kmap_atomic(bvec[f].bv_page, KM_USER0) + bvec[f].bv_offset;
1021                         void *vto = page_address(pkt->pages[p]) + offs;
1022                         memcpy(vto, vfrom, CD_FRAMESIZE);
1023                         kunmap_atomic(vfrom, KM_USER0);
1024                         bvec[f].bv_page = pkt->pages[p];
1025                         bvec[f].bv_offset = offs;
1026                 } else {
1027                         BUG_ON(bvec[f].bv_offset != offs);
1028                 }
1029                 offs += CD_FRAMESIZE;
1030                 if (offs >= PAGE_SIZE) {
1031                         offs = 0;
1032                         p++;
1033                 }
1034         }
1035 }
1036
1037 static void pkt_end_io_read(struct bio *bio, int err)
1038 {
1039         struct packet_data *pkt = bio->bi_private;
1040         struct pktcdvd_device *pd = pkt->pd;
1041         BUG_ON(!pd);
1042
1043         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
1044                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
1045
1046         if (err)
1047                 atomic_inc(&pkt->io_errors);
1048         if (atomic_dec_and_test(&pkt->io_wait)) {
1049                 atomic_inc(&pkt->run_sm);
1050                 wake_up(&pd->wqueue);
1051         }
1052         pkt_bio_finished(pd);
1053 }
1054
1055 static void pkt_end_io_packet_write(struct bio *bio, int err)
1056 {
1057         struct packet_data *pkt = bio->bi_private;
1058         struct pktcdvd_device *pd = pkt->pd;
1059         BUG_ON(!pd);
1060
1061         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1062
1063         pd->stats.pkt_ended++;
1064
1065         pkt_bio_finished(pd);
1066         atomic_dec(&pkt->io_wait);
1067         atomic_inc(&pkt->run_sm);
1068         wake_up(&pd->wqueue);
1069 }
1070
1071 /*
1072  * Schedule reads for the holes in a packet
1073  */
1074 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1075 {
1076         int frames_read = 0;
1077         struct bio *bio;
1078         int f;
1079         char written[PACKET_MAX_SIZE];
1080
1081         BUG_ON(bio_list_empty(&pkt->orig_bios));
1082
1083         atomic_set(&pkt->io_wait, 0);
1084         atomic_set(&pkt->io_errors, 0);
1085
1086         /*
1087          * Figure out which frames we need to read before we can write.
1088          */
1089         memset(written, 0, sizeof(written));
1090         spin_lock(&pkt->lock);
1091         bio_list_for_each(bio, &pkt->orig_bios) {
1092                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1093                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1094                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1095                 BUG_ON(first_frame < 0);
1096                 BUG_ON(first_frame + num_frames > pkt->frames);
1097                 for (f = first_frame; f < first_frame + num_frames; f++)
1098                         written[f] = 1;
1099         }
1100         spin_unlock(&pkt->lock);
1101
1102         if (pkt->cache_valid) {
1103                 VPRINTK("pkt_gather_data: zone %llx cached\n",
1104                         (unsigned long long)pkt->sector);
1105                 goto out_account;
1106         }
1107
1108         /*
1109          * Schedule reads for missing parts of the packet.
1110          */
1111         for (f = 0; f < pkt->frames; f++) {
1112                 struct bio_vec *vec;
1113
1114                 int p, offset;
1115                 if (written[f])
1116                         continue;
1117                 bio = pkt->r_bios[f];
1118                 vec = bio->bi_io_vec;
1119                 bio_init(bio);
1120                 bio->bi_max_vecs = 1;
1121                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1122                 bio->bi_bdev = pd->bdev;
1123                 bio->bi_end_io = pkt_end_io_read;
1124                 bio->bi_private = pkt;
1125                 bio->bi_io_vec = vec;
1126                 bio->bi_destructor = pkt_bio_destructor;
1127
1128                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1129                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1130                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1131                         f, pkt->pages[p], offset);
1132                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1133                         BUG();
1134
1135                 atomic_inc(&pkt->io_wait);
1136                 bio->bi_rw = READ;
1137                 pkt_queue_bio(pd, bio);
1138                 frames_read++;
1139         }
1140
1141 out_account:
1142         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1143                 frames_read, (unsigned long long)pkt->sector);
1144         pd->stats.pkt_started++;
1145         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1146 }
1147
1148 /*
1149  * Find a packet matching zone, or the least recently used packet if
1150  * there is no match.
1151  */
1152 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1153 {
1154         struct packet_data *pkt;
1155
1156         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1157                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1158                         list_del_init(&pkt->list);
1159                         if (pkt->sector != zone)
1160                                 pkt->cache_valid = 0;
1161                         return pkt;
1162                 }
1163         }
1164         BUG();
1165         return NULL;
1166 }
1167
1168 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1169 {
1170         if (pkt->cache_valid) {
1171                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1172         } else {
1173                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1174         }
1175 }
1176
1177 /*
1178  * recover a failed write, query for relocation if possible
1179  *
1180  * returns 1 if recovery is possible, or 0 if not
1181  *
1182  */
1183 static int pkt_start_recovery(struct packet_data *pkt)
1184 {
1185         /*
1186          * FIXME. We need help from the file system to implement
1187          * recovery handling.
1188          */
1189         return 0;
1190 #if 0
1191         struct request *rq = pkt->rq;
1192         struct pktcdvd_device *pd = rq->rq_disk->private_data;
1193         struct block_device *pkt_bdev;
1194         struct super_block *sb = NULL;
1195         unsigned long old_block, new_block;
1196         sector_t new_sector;
1197
1198         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1199         if (pkt_bdev) {
1200                 sb = get_super(pkt_bdev);
1201                 bdput(pkt_bdev);
1202         }
1203
1204         if (!sb)
1205                 return 0;
1206
1207         if (!sb->s_op || !sb->s_op->relocate_blocks)
1208                 goto out;
1209
1210         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1211         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1212                 goto out;
1213
1214         new_sector = new_block * (CD_FRAMESIZE >> 9);
1215         pkt->sector = new_sector;
1216
1217         pkt->bio->bi_sector = new_sector;
1218         pkt->bio->bi_next = NULL;
1219         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
1220         pkt->bio->bi_idx = 0;
1221
1222         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
1223         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
1224         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
1225         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
1226         BUG_ON(pkt->bio->bi_private != pkt);
1227
1228         drop_super(sb);
1229         return 1;
1230
1231 out:
1232         drop_super(sb);
1233         return 0;
1234 #endif
1235 }
1236
1237 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1238 {
1239 #if PACKET_DEBUG > 1
1240         static const char *state_name[] = {
1241                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1242         };
1243         enum packet_data_state old_state = pkt->state;
1244         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1245                 state_name[old_state], state_name[state]);
1246 #endif
1247         pkt->state = state;
1248 }
1249
1250 /*
1251  * Scan the work queue to see if we can start a new packet.
1252  * returns non-zero if any work was done.
1253  */
1254 static int pkt_handle_queue(struct pktcdvd_device *pd)
1255 {
1256         struct packet_data *pkt, *p;
1257         struct bio *bio = NULL;
1258         sector_t zone = 0; /* Suppress gcc warning */
1259         struct pkt_rb_node *node, *first_node;
1260         struct rb_node *n;
1261         int wakeup;
1262
1263         VPRINTK("handle_queue\n");
1264
1265         atomic_set(&pd->scan_queue, 0);
1266
1267         if (list_empty(&pd->cdrw.pkt_free_list)) {
1268                 VPRINTK("handle_queue: no pkt\n");
1269                 return 0;
1270         }
1271
1272         /*
1273          * Try to find a zone we are not already working on.
1274          */
1275         spin_lock(&pd->lock);
1276         first_node = pkt_rbtree_find(pd, pd->current_sector);
1277         if (!first_node) {
1278                 n = rb_first(&pd->bio_queue);
1279                 if (n)
1280                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1281         }
1282         node = first_node;
1283         while (node) {
1284                 bio = node->bio;
1285                 zone = ZONE(bio->bi_sector, pd);
1286                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1287                         if (p->sector == zone) {
1288                                 bio = NULL;
1289                                 goto try_next_bio;
1290                         }
1291                 }
1292                 break;
1293 try_next_bio:
1294                 node = pkt_rbtree_next(node);
1295                 if (!node) {
1296                         n = rb_first(&pd->bio_queue);
1297                         if (n)
1298                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
1299                 }
1300                 if (node == first_node)
1301                         node = NULL;
1302         }
1303         spin_unlock(&pd->lock);
1304         if (!bio) {
1305                 VPRINTK("handle_queue: no bio\n");
1306                 return 0;
1307         }
1308
1309         pkt = pkt_get_packet_data(pd, zone);
1310
1311         pd->current_sector = zone + pd->settings.size;
1312         pkt->sector = zone;
1313         BUG_ON(pkt->frames != pd->settings.size >> 2);
1314         pkt->write_size = 0;
1315
1316         /*
1317          * Scan work queue for bios in the same zone and link them
1318          * to this packet.
1319          */
1320         spin_lock(&pd->lock);
1321         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1322         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1323                 bio = node->bio;
1324                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
1325                         (unsigned long long)ZONE(bio->bi_sector, pd));
1326                 if (ZONE(bio->bi_sector, pd) != zone)
1327                         break;
1328                 pkt_rbtree_erase(pd, node);
1329                 spin_lock(&pkt->lock);
1330                 bio_list_add(&pkt->orig_bios, bio);
1331                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1332                 spin_unlock(&pkt->lock);
1333         }
1334         /* check write congestion marks, and if bio_queue_size is
1335            below, wake up any waiters */
1336         wakeup = (pd->write_congestion_on > 0
1337                         && pd->bio_queue_size <= pd->write_congestion_off);
1338         spin_unlock(&pd->lock);
1339         if (wakeup) {
1340                 clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1341                                         BLK_RW_ASYNC);
1342         }
1343
1344         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1345         pkt_set_state(pkt, PACKET_WAITING_STATE);
1346         atomic_set(&pkt->run_sm, 1);
1347
1348         spin_lock(&pd->cdrw.active_list_lock);
1349         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1350         spin_unlock(&pd->cdrw.active_list_lock);
1351
1352         return 1;
1353 }
1354
1355 /*
1356  * Assemble a bio to write one packet and queue the bio for processing
1357  * by the underlying block device.
1358  */
1359 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1360 {
1361         struct bio *bio;
1362         int f;
1363         int frames_write;
1364         struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1365
1366         for (f = 0; f < pkt->frames; f++) {
1367                 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1368                 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1369         }
1370
1371         /*
1372          * Fill-in bvec with data from orig_bios.
1373          */
1374         frames_write = 0;
1375         spin_lock(&pkt->lock);
1376         bio_list_for_each(bio, &pkt->orig_bios) {
1377                 int segment = bio->bi_idx;
1378                 int src_offs = 0;
1379                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1380                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1381                 BUG_ON(first_frame < 0);
1382                 BUG_ON(first_frame + num_frames > pkt->frames);
1383                 for (f = first_frame; f < first_frame + num_frames; f++) {
1384                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1385
1386                         while (src_offs >= src_bvl->bv_len) {
1387                                 src_offs -= src_bvl->bv_len;
1388                                 segment++;
1389                                 BUG_ON(segment >= bio->bi_vcnt);
1390                                 src_bvl = bio_iovec_idx(bio, segment);
1391                         }
1392
1393                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1394                                 bvec[f].bv_page = src_bvl->bv_page;
1395                                 bvec[f].bv_offset = src_bvl->bv_offset + src_offs;
1396                         } else {
1397                                 pkt_copy_bio_data(bio, segment, src_offs,
1398                                                   bvec[f].bv_page, bvec[f].bv_offset);
1399                         }
1400                         src_offs += CD_FRAMESIZE;
1401                         frames_write++;
1402                 }
1403         }
1404         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1405         spin_unlock(&pkt->lock);
1406
1407         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1408                 frames_write, (unsigned long long)pkt->sector);
1409         BUG_ON(frames_write != pkt->write_size);
1410
1411         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1412                 pkt_make_local_copy(pkt, bvec);
1413                 pkt->cache_valid = 1;
1414         } else {
1415                 pkt->cache_valid = 0;
1416         }
1417
1418         /* Start the write request */
1419         bio_init(pkt->w_bio);
1420         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1421         pkt->w_bio->bi_sector = pkt->sector;
1422         pkt->w_bio->bi_bdev = pd->bdev;
1423         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1424         pkt->w_bio->bi_private = pkt;
1425         pkt->w_bio->bi_io_vec = bvec;
1426         pkt->w_bio->bi_destructor = pkt_bio_destructor;
1427         for (f = 0; f < pkt->frames; f++)
1428                 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1429                         BUG();
1430         VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1431
1432         atomic_set(&pkt->io_wait, 1);
1433         pkt->w_bio->bi_rw = WRITE;
1434         pkt_queue_bio(pd, pkt->w_bio);
1435 }
1436
1437 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1438 {
1439         struct bio *bio;
1440
1441         if (!uptodate)
1442                 pkt->cache_valid = 0;
1443
1444         /* Finish all bios corresponding to this packet */
1445         while ((bio = bio_list_pop(&pkt->orig_bios)))
1446                 bio_endio(bio, uptodate ? 0 : -EIO);
1447 }
1448
1449 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1450 {
1451         int uptodate;
1452
1453         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1454
1455         for (;;) {
1456                 switch (pkt->state) {
1457                 case PACKET_WAITING_STATE:
1458                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1459                                 return;
1460
1461                         pkt->sleep_time = 0;
1462                         pkt_gather_data(pd, pkt);
1463                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1464                         break;
1465
1466                 case PACKET_READ_WAIT_STATE:
1467                         if (atomic_read(&pkt->io_wait) > 0)
1468                                 return;
1469
1470                         if (atomic_read(&pkt->io_errors) > 0) {
1471                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1472                         } else {
1473                                 pkt_start_write(pd, pkt);
1474                         }
1475                         break;
1476
1477                 case PACKET_WRITE_WAIT_STATE:
1478                         if (atomic_read(&pkt->io_wait) > 0)
1479                                 return;
1480
1481                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1482                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1483                         } else {
1484                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1485                         }
1486                         break;
1487
1488                 case PACKET_RECOVERY_STATE:
1489                         if (pkt_start_recovery(pkt)) {
1490                                 pkt_start_write(pd, pkt);
1491                         } else {
1492                                 VPRINTK("No recovery possible\n");
1493                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1494                         }
1495                         break;
1496
1497                 case PACKET_FINISHED_STATE:
1498                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1499                         pkt_finish_packet(pkt, uptodate);
1500                         return;
1501
1502                 default:
1503                         BUG();
1504                         break;
1505                 }
1506         }
1507 }
1508
1509 static void pkt_handle_packets(struct pktcdvd_device *pd)
1510 {
1511         struct packet_data *pkt, *next;
1512
1513         VPRINTK("pkt_handle_packets\n");
1514
1515         /*
1516          * Run state machine for active packets
1517          */
1518         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1519                 if (atomic_read(&pkt->run_sm) > 0) {
1520                         atomic_set(&pkt->run_sm, 0);
1521                         pkt_run_state_machine(pd, pkt);
1522                 }
1523         }
1524
1525         /*
1526          * Move no longer active packets to the free list
1527          */
1528         spin_lock(&pd->cdrw.active_list_lock);
1529         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1530                 if (pkt->state == PACKET_FINISHED_STATE) {
1531                         list_del(&pkt->list);
1532                         pkt_put_packet_data(pd, pkt);
1533                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1534                         atomic_set(&pd->scan_queue, 1);
1535                 }
1536         }
1537         spin_unlock(&pd->cdrw.active_list_lock);
1538 }
1539
1540 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1541 {
1542         struct packet_data *pkt;
1543         int i;
1544
1545         for (i = 0; i < PACKET_NUM_STATES; i++)
1546                 states[i] = 0;
1547
1548         spin_lock(&pd->cdrw.active_list_lock);
1549         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1550                 states[pkt->state]++;
1551         }
1552         spin_unlock(&pd->cdrw.active_list_lock);
1553 }
1554
1555 /*
1556  * kcdrwd is woken up when writes have been queued for one of our
1557  * registered devices
1558  */
1559 static int kcdrwd(void *foobar)
1560 {
1561         struct pktcdvd_device *pd = foobar;
1562         struct packet_data *pkt;
1563         long min_sleep_time, residue;
1564
1565         set_user_nice(current, -20);
1566         set_freezable();
1567
1568         for (;;) {
1569                 DECLARE_WAITQUEUE(wait, current);
1570
1571                 /*
1572                  * Wait until there is something to do
1573                  */
1574                 add_wait_queue(&pd->wqueue, &wait);
1575                 for (;;) {
1576                         set_current_state(TASK_INTERRUPTIBLE);
1577
1578                         /* Check if we need to run pkt_handle_queue */
1579                         if (atomic_read(&pd->scan_queue) > 0)
1580                                 goto work_to_do;
1581
1582                         /* Check if we need to run the state machine for some packet */
1583                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1584                                 if (atomic_read(&pkt->run_sm) > 0)
1585                                         goto work_to_do;
1586                         }
1587
1588                         /* Check if we need to process the iosched queues */
1589                         if (atomic_read(&pd->iosched.attention) != 0)
1590                                 goto work_to_do;
1591
1592                         /* Otherwise, go to sleep */
1593                         if (PACKET_DEBUG > 1) {
1594                                 int states[PACKET_NUM_STATES];
1595                                 pkt_count_states(pd, states);
1596                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1597                                         states[0], states[1], states[2], states[3],
1598                                         states[4], states[5]);
1599                         }
1600
1601                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1602                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1603                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1604                                         min_sleep_time = pkt->sleep_time;
1605                         }
1606
1607                         generic_unplug_device(bdev_get_queue(pd->bdev));
1608
1609                         VPRINTK("kcdrwd: sleeping\n");
1610                         residue = schedule_timeout(min_sleep_time);
1611                         VPRINTK("kcdrwd: wake up\n");
1612
1613                         /* make swsusp happy with our thread */
1614                         try_to_freeze();
1615
1616                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1617                                 if (!pkt->sleep_time)
1618                                         continue;
1619                                 pkt->sleep_time -= min_sleep_time - residue;
1620                                 if (pkt->sleep_time <= 0) {
1621                                         pkt->sleep_time = 0;
1622                                         atomic_inc(&pkt->run_sm);
1623                                 }
1624                         }
1625
1626                         if (kthread_should_stop())
1627                                 break;
1628                 }
1629 work_to_do:
1630                 set_current_state(TASK_RUNNING);
1631                 remove_wait_queue(&pd->wqueue, &wait);
1632
1633                 if (kthread_should_stop())
1634                         break;
1635
1636                 /*
1637                  * if pkt_handle_queue returns true, we can queue
1638                  * another request.
1639                  */
1640                 while (pkt_handle_queue(pd))
1641                         ;
1642
1643                 /*
1644                  * Handle packet state machine
1645                  */
1646                 pkt_handle_packets(pd);
1647
1648                 /*
1649                  * Handle iosched queues
1650                  */
1651                 pkt_iosched_process_queue(pd);
1652         }
1653
1654         return 0;
1655 }
1656
1657 static void pkt_print_settings(struct pktcdvd_device *pd)
1658 {
1659         printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1660         printk("%u blocks, ", pd->settings.size >> 2);
1661         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1662 }
1663
1664 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1665 {
1666         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1667
1668         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1669         cgc->cmd[2] = page_code | (page_control << 6);
1670         cgc->cmd[7] = cgc->buflen >> 8;
1671         cgc->cmd[8] = cgc->buflen & 0xff;
1672         cgc->data_direction = CGC_DATA_READ;
1673         return pkt_generic_packet(pd, cgc);
1674 }
1675
1676 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1677 {
1678         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1679         memset(cgc->buffer, 0, 2);
1680         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1681         cgc->cmd[1] = 0x10;             /* PF */
1682         cgc->cmd[7] = cgc->buflen >> 8;
1683         cgc->cmd[8] = cgc->buflen & 0xff;
1684         cgc->data_direction = CGC_DATA_WRITE;
1685         return pkt_generic_packet(pd, cgc);
1686 }
1687
1688 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1689 {
1690         struct packet_command cgc;
1691         int ret;
1692
1693         /* set up command and get the disc info */
1694         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1695         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1696         cgc.cmd[8] = cgc.buflen = 2;
1697         cgc.quiet = 1;
1698
1699         if ((ret = pkt_generic_packet(pd, &cgc)))
1700                 return ret;
1701
1702         /* not all drives have the same disc_info length, so requeue
1703          * packet with the length the drive tells us it can supply
1704          */
1705         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1706                      sizeof(di->disc_information_length);
1707
1708         if (cgc.buflen > sizeof(disc_information))
1709                 cgc.buflen = sizeof(disc_information);
1710
1711         cgc.cmd[8] = cgc.buflen;
1712         return pkt_generic_packet(pd, &cgc);
1713 }
1714
1715 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1716 {
1717         struct packet_command cgc;
1718         int ret;
1719
1720         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1721         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1722         cgc.cmd[1] = type & 3;
1723         cgc.cmd[4] = (track & 0xff00) >> 8;
1724         cgc.cmd[5] = track & 0xff;
1725         cgc.cmd[8] = 8;
1726         cgc.quiet = 1;
1727
1728         if ((ret = pkt_generic_packet(pd, &cgc)))
1729                 return ret;
1730
1731         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1732                      sizeof(ti->track_information_length);
1733
1734         if (cgc.buflen > sizeof(track_information))
1735                 cgc.buflen = sizeof(track_information);
1736
1737         cgc.cmd[8] = cgc.buflen;
1738         return pkt_generic_packet(pd, &cgc);
1739 }
1740
1741 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1742                                                 long *last_written)
1743 {
1744         disc_information di;
1745         track_information ti;
1746         __u32 last_track;
1747         int ret = -1;
1748
1749         if ((ret = pkt_get_disc_info(pd, &di)))
1750                 return ret;
1751
1752         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1753         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1754                 return ret;
1755
1756         /* if this track is blank, try the previous. */
1757         if (ti.blank) {
1758                 last_track--;
1759                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1760                         return ret;
1761         }
1762
1763         /* if last recorded field is valid, return it. */
1764         if (ti.lra_v) {
1765                 *last_written = be32_to_cpu(ti.last_rec_address);
1766         } else {
1767                 /* make it up instead */
1768                 *last_written = be32_to_cpu(ti.track_start) +
1769                                 be32_to_cpu(ti.track_size);
1770                 if (ti.free_blocks)
1771                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1772         }
1773         return 0;
1774 }
1775
1776 /*
1777  * write mode select package based on pd->settings
1778  */
1779 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1780 {
1781         struct packet_command cgc;
1782         struct request_sense sense;
1783         write_param_page *wp;
1784         char buffer[128];
1785         int ret, size;
1786
1787         /* doesn't apply to DVD+RW or DVD-RAM */
1788         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1789                 return 0;
1790
1791         memset(buffer, 0, sizeof(buffer));
1792         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1793         cgc.sense = &sense;
1794         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1795                 pkt_dump_sense(&cgc);
1796                 return ret;
1797         }
1798
1799         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1800         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1801         if (size > sizeof(buffer))
1802                 size = sizeof(buffer);
1803
1804         /*
1805          * now get it all
1806          */
1807         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1808         cgc.sense = &sense;
1809         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1810                 pkt_dump_sense(&cgc);
1811                 return ret;
1812         }
1813
1814         /*
1815          * write page is offset header + block descriptor length
1816          */
1817         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1818
1819         wp->fp = pd->settings.fp;
1820         wp->track_mode = pd->settings.track_mode;
1821         wp->write_type = pd->settings.write_type;
1822         wp->data_block_type = pd->settings.block_mode;
1823
1824         wp->multi_session = 0;
1825
1826 #ifdef PACKET_USE_LS
1827         wp->link_size = 7;
1828         wp->ls_v = 1;
1829 #endif
1830
1831         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1832                 wp->session_format = 0;
1833                 wp->subhdr2 = 0x20;
1834         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1835                 wp->session_format = 0x20;
1836                 wp->subhdr2 = 8;
1837 #if 0
1838                 wp->mcn[0] = 0x80;
1839                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1840 #endif
1841         } else {
1842                 /*
1843                  * paranoia
1844                  */
1845                 printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1846                 return 1;
1847         }
1848         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1849
1850         cgc.buflen = cgc.cmd[8] = size;
1851         if ((ret = pkt_mode_select(pd, &cgc))) {
1852                 pkt_dump_sense(&cgc);
1853                 return ret;
1854         }
1855
1856         pkt_print_settings(pd);
1857         return 0;
1858 }
1859
1860 /*
1861  * 1 -- we can write to this track, 0 -- we can't
1862  */
1863 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1864 {
1865         switch (pd->mmc3_profile) {
1866                 case 0x1a: /* DVD+RW */
1867                 case 0x12: /* DVD-RAM */
1868                         /* The track is always writable on DVD+RW/DVD-RAM */
1869                         return 1;
1870                 default:
1871                         break;
1872         }
1873
1874         if (!ti->packet || !ti->fp)
1875                 return 0;
1876
1877         /*
1878          * "good" settings as per Mt Fuji.
1879          */
1880         if (ti->rt == 0 && ti->blank == 0)
1881                 return 1;
1882
1883         if (ti->rt == 0 && ti->blank == 1)
1884                 return 1;
1885
1886         if (ti->rt == 1 && ti->blank == 0)
1887                 return 1;
1888
1889         printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1890         return 0;
1891 }
1892
1893 /*
1894  * 1 -- we can write to this disc, 0 -- we can't
1895  */
1896 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1897 {
1898         switch (pd->mmc3_profile) {
1899                 case 0x0a: /* CD-RW */
1900                 case 0xffff: /* MMC3 not supported */
1901                         break;
1902                 case 0x1a: /* DVD+RW */
1903                 case 0x13: /* DVD-RW */
1904                 case 0x12: /* DVD-RAM */
1905                         return 1;
1906                 default:
1907                         VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1908                         return 0;
1909         }
1910
1911         /*
1912          * for disc type 0xff we should probably reserve a new track.
1913          * but i'm not sure, should we leave this to user apps? probably.
1914          */
1915         if (di->disc_type == 0xff) {
1916                 printk(DRIVER_NAME": Unknown disc. No track?\n");
1917                 return 0;
1918         }
1919
1920         if (di->disc_type != 0x20 && di->disc_type != 0) {
1921                 printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1922                 return 0;
1923         }
1924
1925         if (di->erasable == 0) {
1926                 printk(DRIVER_NAME": Disc not erasable\n");
1927                 return 0;
1928         }
1929
1930         if (di->border_status == PACKET_SESSION_RESERVED) {
1931                 printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1932                 return 0;
1933         }
1934
1935         return 1;
1936 }
1937
1938 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1939 {
1940         struct packet_command cgc;
1941         unsigned char buf[12];
1942         disc_information di;
1943         track_information ti;
1944         int ret, track;
1945
1946         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1947         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1948         cgc.cmd[8] = 8;
1949         ret = pkt_generic_packet(pd, &cgc);
1950         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1951
1952         memset(&di, 0, sizeof(disc_information));
1953         memset(&ti, 0, sizeof(track_information));
1954
1955         if ((ret = pkt_get_disc_info(pd, &di))) {
1956                 printk("failed get_disc\n");
1957                 return ret;
1958         }
1959
1960         if (!pkt_writable_disc(pd, &di))
1961                 return -EROFS;
1962
1963         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1964
1965         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1966         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1967                 printk(DRIVER_NAME": failed get_track\n");
1968                 return ret;
1969         }
1970
1971         if (!pkt_writable_track(pd, &ti)) {
1972                 printk(DRIVER_NAME": can't write to this track\n");
1973                 return -EROFS;
1974         }
1975
1976         /*
1977          * we keep packet size in 512 byte units, makes it easier to
1978          * deal with request calculations.
1979          */
1980         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1981         if (pd->settings.size == 0) {
1982                 printk(DRIVER_NAME": detected zero packet size!\n");
1983                 return -ENXIO;
1984         }
1985         if (pd->settings.size > PACKET_MAX_SECTORS) {
1986                 printk(DRIVER_NAME": packet size is too big\n");
1987                 return -EROFS;
1988         }
1989         pd->settings.fp = ti.fp;
1990         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1991
1992         if (ti.nwa_v) {
1993                 pd->nwa = be32_to_cpu(ti.next_writable);
1994                 set_bit(PACKET_NWA_VALID, &pd->flags);
1995         }
1996
1997         /*
1998          * in theory we could use lra on -RW media as well and just zero
1999          * blocks that haven't been written yet, but in practice that
2000          * is just a no-go. we'll use that for -R, naturally.
2001          */
2002         if (ti.lra_v) {
2003                 pd->lra = be32_to_cpu(ti.last_rec_address);
2004                 set_bit(PACKET_LRA_VALID, &pd->flags);
2005         } else {
2006                 pd->lra = 0xffffffff;
2007                 set_bit(PACKET_LRA_VALID, &pd->flags);
2008         }
2009
2010         /*
2011          * fine for now
2012          */
2013         pd->settings.link_loss = 7;
2014         pd->settings.write_type = 0;    /* packet */
2015         pd->settings.track_mode = ti.track_mode;
2016
2017         /*
2018          * mode1 or mode2 disc
2019          */
2020         switch (ti.data_mode) {
2021                 case PACKET_MODE1:
2022                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
2023                         break;
2024                 case PACKET_MODE2:
2025                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
2026                         break;
2027                 default:
2028                         printk(DRIVER_NAME": unknown data mode\n");
2029                         return -EROFS;
2030         }
2031         return 0;
2032 }
2033
2034 /*
2035  * enable/disable write caching on drive
2036  */
2037 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
2038                                                 int set)
2039 {
2040         struct packet_command cgc;
2041         struct request_sense sense;
2042         unsigned char buf[64];
2043         int ret;
2044
2045         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
2046         cgc.sense = &sense;
2047         cgc.buflen = pd->mode_offset + 12;
2048
2049         /*
2050          * caching mode page might not be there, so quiet this command
2051          */
2052         cgc.quiet = 1;
2053
2054         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
2055                 return ret;
2056
2057         buf[pd->mode_offset + 10] |= (!!set << 2);
2058
2059         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
2060         ret = pkt_mode_select(pd, &cgc);
2061         if (ret) {
2062                 printk(DRIVER_NAME": write caching control failed\n");
2063                 pkt_dump_sense(&cgc);
2064         } else if (!ret && set)
2065                 printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
2066         return ret;
2067 }
2068
2069 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
2070 {
2071         struct packet_command cgc;
2072
2073         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2074         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
2075         cgc.cmd[4] = lockflag ? 1 : 0;
2076         return pkt_generic_packet(pd, &cgc);
2077 }
2078
2079 /*
2080  * Returns drive maximum write speed
2081  */
2082 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
2083                                                 unsigned *write_speed)
2084 {
2085         struct packet_command cgc;
2086         struct request_sense sense;
2087         unsigned char buf[256+18];
2088         unsigned char *cap_buf;
2089         int ret, offset;
2090
2091         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
2092         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2093         cgc.sense = &sense;
2094
2095         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2096         if (ret) {
2097                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2098                              sizeof(struct mode_page_header);
2099                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2100                 if (ret) {
2101                         pkt_dump_sense(&cgc);
2102                         return ret;
2103                 }
2104         }
2105
2106         offset = 20;                        /* Obsoleted field, used by older drives */
2107         if (cap_buf[1] >= 28)
2108                 offset = 28;                /* Current write speed selected */
2109         if (cap_buf[1] >= 30) {
2110                 /* If the drive reports at least one "Logical Unit Write
2111                  * Speed Performance Descriptor Block", use the information
2112                  * in the first block. (contains the highest speed)
2113                  */
2114                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2115                 if (num_spdb > 0)
2116                         offset = 34;
2117         }
2118
2119         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2120         return 0;
2121 }
2122
2123 /* These tables from cdrecord - I don't have orange book */
2124 /* standard speed CD-RW (1-4x) */
2125 static char clv_to_speed[16] = {
2126         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2127            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2128 };
2129 /* high speed CD-RW (-10x) */
2130 static char hs_clv_to_speed[16] = {
2131         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2132            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2133 };
2134 /* ultra high speed CD-RW */
2135 static char us_clv_to_speed[16] = {
2136         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2137            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2138 };
2139
2140 /*
2141  * reads the maximum media speed from ATIP
2142  */
2143 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2144                                                 unsigned *speed)
2145 {
2146         struct packet_command cgc;
2147         struct request_sense sense;
2148         unsigned char buf[64];
2149         unsigned int size, st, sp;
2150         int ret;
2151
2152         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2153         cgc.sense = &sense;
2154         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2155         cgc.cmd[1] = 2;
2156         cgc.cmd[2] = 4; /* READ ATIP */
2157         cgc.cmd[8] = 2;
2158         ret = pkt_generic_packet(pd, &cgc);
2159         if (ret) {
2160                 pkt_dump_sense(&cgc);
2161                 return ret;
2162         }
2163         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2164         if (size > sizeof(buf))
2165                 size = sizeof(buf);
2166
2167         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2168         cgc.sense = &sense;
2169         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2170         cgc.cmd[1] = 2;
2171         cgc.cmd[2] = 4;
2172         cgc.cmd[8] = size;
2173         ret = pkt_generic_packet(pd, &cgc);
2174         if (ret) {
2175                 pkt_dump_sense(&cgc);
2176                 return ret;
2177         }
2178
2179         if (!(buf[6] & 0x40)) {
2180                 printk(DRIVER_NAME": Disc type is not CD-RW\n");
2181                 return 1;
2182         }
2183         if (!(buf[6] & 0x4)) {
2184                 printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2185                 return 1;
2186         }
2187
2188         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2189
2190         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2191
2192         /* Info from cdrecord */
2193         switch (st) {
2194                 case 0: /* standard speed */
2195                         *speed = clv_to_speed[sp];
2196                         break;
2197                 case 1: /* high speed */
2198                         *speed = hs_clv_to_speed[sp];
2199                         break;
2200                 case 2: /* ultra high speed */
2201                         *speed = us_clv_to_speed[sp];
2202                         break;
2203                 default:
2204                         printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2205                         return 1;
2206         }
2207         if (*speed) {
2208                 printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2209                 return 0;
2210         } else {
2211                 printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2212                 return 1;
2213         }
2214 }
2215
2216 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2217 {
2218         struct packet_command cgc;
2219         struct request_sense sense;
2220         int ret;
2221
2222         VPRINTK(DRIVER_NAME": Performing OPC\n");
2223
2224         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2225         cgc.sense = &sense;
2226         cgc.timeout = 60*HZ;
2227         cgc.cmd[0] = GPCMD_SEND_OPC;
2228         cgc.cmd[1] = 1;
2229         if ((ret = pkt_generic_packet(pd, &cgc)))
2230                 pkt_dump_sense(&cgc);
2231         return ret;
2232 }
2233
2234 static int pkt_open_write(struct pktcdvd_device *pd)
2235 {
2236         int ret;
2237         unsigned int write_speed, media_write_speed, read_speed;
2238
2239         if ((ret = pkt_probe_settings(pd))) {
2240                 VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2241                 return ret;
2242         }
2243
2244         if ((ret = pkt_set_write_settings(pd))) {
2245                 DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2246                 return -EIO;
2247         }
2248
2249         pkt_write_caching(pd, USE_WCACHING);
2250
2251         if ((ret = pkt_get_max_speed(pd, &write_speed)))
2252                 write_speed = 16 * 177;
2253         switch (pd->mmc3_profile) {
2254                 case 0x13: /* DVD-RW */
2255                 case 0x1a: /* DVD+RW */
2256                 case 0x12: /* DVD-RAM */
2257                         DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2258                         break;
2259                 default:
2260                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
2261                                 media_write_speed = 16;
2262                         write_speed = min(write_speed, media_write_speed * 177);
2263                         DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2264                         break;
2265         }
2266         read_speed = write_speed;
2267
2268         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2269                 DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2270                 return -EIO;
2271         }
2272         pd->write_speed = write_speed;
2273         pd->read_speed = read_speed;
2274
2275         if ((ret = pkt_perform_opc(pd))) {
2276                 DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2277         }
2278
2279         return 0;
2280 }
2281
2282 /*
2283  * called at open time.
2284  */
2285 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2286 {
2287         int ret;
2288         long lba;
2289         struct request_queue *q;
2290
2291         /*
2292          * We need to re-open the cdrom device without O_NONBLOCK to be able
2293          * to read/write from/to it. It is already opened in O_NONBLOCK mode
2294          * so bdget() can't fail.
2295          */
2296         bdget(pd->bdev->bd_dev);
2297         if ((ret = blkdev_get(pd->bdev, FMODE_READ)))
2298                 goto out;
2299
2300         if ((ret = bd_claim(pd->bdev, pd)))
2301                 goto out_putdev;
2302
2303         if ((ret = pkt_get_last_written(pd, &lba))) {
2304                 printk(DRIVER_NAME": pkt_get_last_written failed\n");
2305                 goto out_unclaim;
2306         }
2307
2308         set_capacity(pd->disk, lba << 2);
2309         set_capacity(pd->bdev->bd_disk, lba << 2);
2310         bd_set_size(pd->bdev, (loff_t)lba << 11);
2311
2312         q = bdev_get_queue(pd->bdev);
2313         if (write) {
2314                 if ((ret = pkt_open_write(pd)))
2315                         goto out_unclaim;
2316                 /*
2317                  * Some CDRW drives can not handle writes larger than one packet,
2318                  * even if the size is a multiple of the packet size.
2319                  */
2320                 spin_lock_irq(q->queue_lock);
2321                 blk_queue_max_hw_sectors(q, pd->settings.size);
2322                 spin_unlock_irq(q->queue_lock);
2323                 set_bit(PACKET_WRITABLE, &pd->flags);
2324         } else {
2325                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2326                 clear_bit(PACKET_WRITABLE, &pd->flags);
2327         }
2328
2329         if ((ret = pkt_set_segment_merging(pd, q)))
2330                 goto out_unclaim;
2331
2332         if (write) {
2333                 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2334                         printk(DRIVER_NAME": not enough memory for buffers\n");
2335                         ret = -ENOMEM;
2336                         goto out_unclaim;
2337                 }
2338                 printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2339         }
2340
2341         return 0;
2342
2343 out_unclaim:
2344         bd_release(pd->bdev);
2345 out_putdev:
2346         blkdev_put(pd->bdev, FMODE_READ);
2347 out:
2348         return ret;
2349 }
2350
2351 /*
2352  * called when the device is closed. makes sure that the device flushes
2353  * the internal cache before we close.
2354  */
2355 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2356 {
2357         if (flush && pkt_flush_cache(pd))
2358                 DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2359
2360         pkt_lock_door(pd, 0);
2361
2362         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2363         bd_release(pd->bdev);
2364         blkdev_put(pd->bdev, FMODE_READ);
2365
2366         pkt_shrink_pktlist(pd);
2367 }
2368
2369 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2370 {
2371         if (dev_minor >= MAX_WRITERS)
2372                 return NULL;
2373         return pkt_devs[dev_minor];
2374 }
2375
2376 static int pkt_open(struct block_device *bdev, fmode_t mode)
2377 {
2378         struct pktcdvd_device *pd = NULL;
2379         int ret;
2380
2381         VPRINTK(DRIVER_NAME": entering open\n");
2382
2383         mutex_lock(&ctl_mutex);
2384         pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2385         if (!pd) {
2386                 ret = -ENODEV;
2387                 goto out;
2388         }
2389         BUG_ON(pd->refcnt < 0);
2390
2391         pd->refcnt++;
2392         if (pd->refcnt > 1) {
2393                 if ((mode & FMODE_WRITE) &&
2394                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2395                         ret = -EBUSY;
2396                         goto out_dec;
2397                 }
2398         } else {
2399                 ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2400                 if (ret)
2401                         goto out_dec;
2402                 /*
2403                  * needed here as well, since ext2 (among others) may change
2404                  * the blocksize at mount time
2405                  */
2406                 set_blocksize(bdev, CD_FRAMESIZE);
2407         }
2408
2409         mutex_unlock(&ctl_mutex);
2410         return 0;
2411
2412 out_dec:
2413         pd->refcnt--;
2414 out:
2415         VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2416         mutex_unlock(&ctl_mutex);
2417         return ret;
2418 }
2419
2420 static int pkt_close(struct gendisk *disk, fmode_t mode)
2421 {
2422         struct pktcdvd_device *pd = disk->private_data;
2423         int ret = 0;
2424
2425         mutex_lock(&ctl_mutex);
2426         pd->refcnt--;
2427         BUG_ON(pd->refcnt < 0);
2428         if (pd->refcnt == 0) {
2429                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2430                 pkt_release_dev(pd, flush);
2431         }
2432         mutex_unlock(&ctl_mutex);
2433         return ret;
2434 }
2435
2436
2437 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2438 {
2439         struct packet_stacked_data *psd = bio->bi_private;
2440         struct pktcdvd_device *pd = psd->pd;
2441
2442         bio_put(bio);
2443         bio_endio(psd->bio, err);
2444         mempool_free(psd, psd_pool);
2445         pkt_bio_finished(pd);
2446 }
2447
2448 static int pkt_make_request(struct request_queue *q, struct bio *bio)
2449 {
2450         struct pktcdvd_device *pd;
2451         char b[BDEVNAME_SIZE];
2452         sector_t zone;
2453         struct packet_data *pkt;
2454         int was_empty, blocked_bio;
2455         struct pkt_rb_node *node;
2456
2457         pd = q->queuedata;
2458         if (!pd) {
2459                 printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2460                 goto end_io;
2461         }
2462
2463         /*
2464          * Clone READ bios so we can have our own bi_end_io callback.
2465          */
2466         if (bio_data_dir(bio) == READ) {
2467                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2468                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2469
2470                 psd->pd = pd;
2471                 psd->bio = bio;
2472                 cloned_bio->bi_bdev = pd->bdev;
2473                 cloned_bio->bi_private = psd;
2474                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2475                 pd->stats.secs_r += bio->bi_size >> 9;
2476                 pkt_queue_bio(pd, cloned_bio);
2477                 return 0;
2478         }
2479
2480         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2481                 printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2482                         pd->name, (unsigned long long)bio->bi_sector);
2483                 goto end_io;
2484         }
2485
2486         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2487                 printk(DRIVER_NAME": wrong bio size\n");
2488                 goto end_io;
2489         }
2490
2491         blk_queue_bounce(q, &bio);
2492
2493         zone = ZONE(bio->bi_sector, pd);
2494         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2495                 (unsigned long long)bio->bi_sector,
2496                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2497
2498         /* Check if we have to split the bio */
2499         {
2500                 struct bio_pair *bp;
2501                 sector_t last_zone;
2502                 int first_sectors;
2503
2504                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2505                 if (last_zone != zone) {
2506                         BUG_ON(last_zone != zone + pd->settings.size);
2507                         first_sectors = last_zone - bio->bi_sector;
2508                         bp = bio_split(bio, first_sectors);
2509                         BUG_ON(!bp);
2510                         pkt_make_request(q, &bp->bio1);
2511                         pkt_make_request(q, &bp->bio2);
2512                         bio_pair_release(bp);
2513                         return 0;
2514                 }
2515         }
2516
2517         /*
2518          * If we find a matching packet in state WAITING or READ_WAIT, we can
2519          * just append this bio to that packet.
2520          */
2521         spin_lock(&pd->cdrw.active_list_lock);
2522         blocked_bio = 0;
2523         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2524                 if (pkt->sector == zone) {
2525                         spin_lock(&pkt->lock);
2526                         if ((pkt->state == PACKET_WAITING_STATE) ||
2527                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2528                                 bio_list_add(&pkt->orig_bios, bio);
2529                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2530                                 if ((pkt->write_size >= pkt->frames) &&
2531                                     (pkt->state == PACKET_WAITING_STATE)) {
2532                                         atomic_inc(&pkt->run_sm);
2533                                         wake_up(&pd->wqueue);
2534                                 }
2535                                 spin_unlock(&pkt->lock);
2536                                 spin_unlock(&pd->cdrw.active_list_lock);
2537                                 return 0;
2538                         } else {
2539                                 blocked_bio = 1;
2540                         }
2541                         spin_unlock(&pkt->lock);
2542                 }
2543         }
2544         spin_unlock(&pd->cdrw.active_list_lock);
2545
2546         /*
2547          * Test if there is enough room left in the bio work queue
2548          * (queue size >= congestion on mark).
2549          * If not, wait till the work queue size is below the congestion off mark.
2550          */
2551         spin_lock(&pd->lock);
2552         if (pd->write_congestion_on > 0
2553             && pd->bio_queue_size >= pd->write_congestion_on) {
2554                 set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2555                 do {
2556                         spin_unlock(&pd->lock);
2557                         congestion_wait(BLK_RW_ASYNC, HZ);
2558                         spin_lock(&pd->lock);
2559                 } while(pd->bio_queue_size > pd->write_congestion_off);
2560         }
2561         spin_unlock(&pd->lock);
2562
2563         /*
2564          * No matching packet found. Store the bio in the work queue.
2565          */
2566         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2567         node->bio = bio;
2568         spin_lock(&pd->lock);
2569         BUG_ON(pd->bio_queue_size < 0);
2570         was_empty = (pd->bio_queue_size == 0);
2571         pkt_rbtree_insert(pd, node);
2572         spin_unlock(&pd->lock);
2573
2574         /*
2575          * Wake up the worker thread.
2576          */
2577         atomic_set(&pd->scan_queue, 1);
2578         if (was_empty) {
2579                 /* This wake_up is required for correct operation */
2580                 wake_up(&pd->wqueue);
2581         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2582                 /*
2583                  * This wake up is not required for correct operation,
2584                  * but improves performance in some cases.
2585                  */
2586                 wake_up(&pd->wqueue);
2587         }
2588         return 0;
2589 end_io:
2590         bio_io_error(bio);
2591         return 0;
2592 }
2593
2594
2595
2596 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2597                           struct bio_vec *bvec)
2598 {
2599         struct pktcdvd_device *pd = q->queuedata;
2600         sector_t zone = ZONE(bmd->bi_sector, pd);
2601         int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2602         int remaining = (pd->settings.size << 9) - used;
2603         int remaining2;
2604
2605         /*
2606          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2607          * boundary, pkt_make_request() will split the bio.
2608          */
2609         remaining2 = PAGE_SIZE - bmd->bi_size;
2610         remaining = max(remaining, remaining2);
2611
2612         BUG_ON(remaining < 0);
2613         return remaining;
2614 }
2615
2616 static void pkt_init_queue(struct pktcdvd_device *pd)
2617 {
2618         struct request_queue *q = pd->disk->queue;
2619
2620         blk_queue_make_request(q, pkt_make_request);
2621         blk_queue_logical_block_size(q, CD_FRAMESIZE);
2622         blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2623         blk_queue_merge_bvec(q, pkt_merge_bvec);
2624         q->queuedata = pd;
2625 }
2626
2627 static int pkt_seq_show(struct seq_file *m, void *p)
2628 {
2629         struct pktcdvd_device *pd = m->private;
2630         char *msg;
2631         char bdev_buf[BDEVNAME_SIZE];
2632         int states[PACKET_NUM_STATES];
2633
2634         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2635                    bdevname(pd->bdev, bdev_buf));
2636
2637         seq_printf(m, "\nSettings:\n");
2638         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2639
2640         if (pd->settings.write_type == 0)
2641                 msg = "Packet";
2642         else
2643                 msg = "Unknown";
2644         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2645
2646         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2647         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2648
2649         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2650
2651         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2652                 msg = "Mode 1";
2653         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2654                 msg = "Mode 2";
2655         else
2656                 msg = "Unknown";
2657         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2658
2659         seq_printf(m, "\nStatistics:\n");
2660         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2661         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2662         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2663         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2664         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2665
2666         seq_printf(m, "\nMisc:\n");
2667         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2668         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2669         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2670         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2671         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2672         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2673
2674         seq_printf(m, "\nQueue state:\n");
2675         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2676         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2677         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2678
2679         pkt_count_states(pd, states);
2680         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2681                    states[0], states[1], states[2], states[3], states[4], states[5]);
2682
2683         seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2684                         pd->write_congestion_off,
2685                         pd->write_congestion_on);
2686         return 0;
2687 }
2688
2689 static int pkt_seq_open(struct inode *inode, struct file *file)
2690 {
2691         return single_open(file, pkt_seq_show, PDE(inode)->data);
2692 }
2693
2694 static const struct file_operations pkt_proc_fops = {
2695         .open   = pkt_seq_open,
2696         .read   = seq_read,
2697         .llseek = seq_lseek,
2698         .release = single_release
2699 };
2700
2701 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2702 {
2703         int i;
2704         int ret = 0;
2705         char b[BDEVNAME_SIZE];
2706         struct block_device *bdev;
2707
2708         if (pd->pkt_dev == dev) {
2709                 printk(DRIVER_NAME": Recursive setup not allowed\n");
2710                 return -EBUSY;
2711         }
2712         for (i = 0; i < MAX_WRITERS; i++) {
2713                 struct pktcdvd_device *pd2 = pkt_devs[i];
2714                 if (!pd2)
2715                         continue;
2716                 if (pd2->bdev->bd_dev == dev) {
2717                         printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
2718                         return -EBUSY;
2719                 }
2720                 if (pd2->pkt_dev == dev) {
2721                         printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2722                         return -EBUSY;
2723                 }
2724         }
2725
2726         bdev = bdget(dev);
2727         if (!bdev)
2728                 return -ENOMEM;
2729         ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY);
2730         if (ret)
2731                 return ret;
2732
2733         /* This is safe, since we have a reference from open(). */
2734         __module_get(THIS_MODULE);
2735
2736         pd->bdev = bdev;
2737         set_blocksize(bdev, CD_FRAMESIZE);
2738
2739         pkt_init_queue(pd);
2740
2741         atomic_set(&pd->cdrw.pending_bios, 0);
2742         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2743         if (IS_ERR(pd->cdrw.thread)) {
2744                 printk(DRIVER_NAME": can't start kernel thread\n");
2745                 ret = -ENOMEM;
2746                 goto out_mem;
2747         }
2748
2749         proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2750         DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2751         return 0;
2752
2753 out_mem:
2754         blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2755         /* This is safe: open() is still holding a reference. */
2756         module_put(THIS_MODULE);
2757         return ret;
2758 }
2759
2760 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2761 {
2762         struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2763
2764         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2765                 MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2766
2767         switch (cmd) {
2768         case CDROMEJECT:
2769                 /*
2770                  * The door gets locked when the device is opened, so we
2771                  * have to unlock it or else the eject command fails.
2772                  */
2773                 if (pd->refcnt == 1)
2774                         pkt_lock_door(pd, 0);
2775                 /* fallthru */
2776         /*
2777          * forward selected CDROM ioctls to CD-ROM, for UDF
2778          */
2779         case CDROMMULTISESSION:
2780         case CDROMREADTOCENTRY:
2781         case CDROM_LAST_WRITTEN:
2782         case CDROM_SEND_PACKET:
2783         case SCSI_IOCTL_SEND_COMMAND:
2784                 return __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2785
2786         default:
2787                 VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2788                 return -ENOTTY;
2789         }
2790
2791         return 0;
2792 }
2793
2794 static int pkt_media_changed(struct gendisk *disk)
2795 {
2796         struct pktcdvd_device *pd = disk->private_data;
2797         struct gendisk *attached_disk;
2798
2799         if (!pd)
2800                 return 0;
2801         if (!pd->bdev)
2802                 return 0;
2803         attached_disk = pd->bdev->bd_disk;
2804         if (!attached_disk)
2805                 return 0;
2806         return attached_disk->fops->media_changed(attached_disk);
2807 }
2808
2809 static const struct block_device_operations pktcdvd_ops = {
2810         .owner =                THIS_MODULE,
2811         .open =                 pkt_open,
2812         .release =              pkt_close,
2813         .locked_ioctl =         pkt_ioctl,
2814         .media_changed =        pkt_media_changed,
2815 };
2816
2817 static char *pktcdvd_devnode(struct gendisk *gd, mode_t *mode)
2818 {
2819         return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2820 }
2821
2822 /*
2823  * Set up mapping from pktcdvd device to CD-ROM device.
2824  */
2825 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2826 {
2827         int idx;
2828         int ret = -ENOMEM;
2829         struct pktcdvd_device *pd;
2830         struct gendisk *disk;
2831
2832         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2833
2834         for (idx = 0; idx < MAX_WRITERS; idx++)
2835                 if (!pkt_devs[idx])
2836                         break;
2837         if (idx == MAX_WRITERS) {
2838                 printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2839                 ret = -EBUSY;
2840                 goto out_mutex;
2841         }
2842
2843         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2844         if (!pd)
2845                 goto out_mutex;
2846
2847         pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2848                                                   sizeof(struct pkt_rb_node));
2849         if (!pd->rb_pool)
2850                 goto out_mem;
2851
2852         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2853         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2854         spin_lock_init(&pd->cdrw.active_list_lock);
2855
2856         spin_lock_init(&pd->lock);
2857         spin_lock_init(&pd->iosched.lock);
2858         bio_list_init(&pd->iosched.read_queue);
2859         bio_list_init(&pd->iosched.write_queue);
2860         sprintf(pd->name, DRIVER_NAME"%d", idx);
2861         init_waitqueue_head(&pd->wqueue);
2862         pd->bio_queue = RB_ROOT;
2863
2864         pd->write_congestion_on  = write_congestion_on;
2865         pd->write_congestion_off = write_congestion_off;
2866
2867         disk = alloc_disk(1);
2868         if (!disk)
2869                 goto out_mem;
2870         pd->disk = disk;
2871         disk->major = pktdev_major;
2872         disk->first_minor = idx;
2873         disk->fops = &pktcdvd_ops;
2874         disk->flags = GENHD_FL_REMOVABLE;
2875         strcpy(disk->disk_name, pd->name);
2876         disk->devnode = pktcdvd_devnode;
2877         disk->private_data = pd;
2878         disk->queue = blk_alloc_queue(GFP_KERNEL);
2879         if (!disk->queue)
2880                 goto out_mem2;
2881
2882         pd->pkt_dev = MKDEV(pktdev_major, idx);
2883         ret = pkt_new_dev(pd, dev);
2884         if (ret)
2885                 goto out_new_dev;
2886
2887         add_disk(disk);
2888
2889         pkt_sysfs_dev_new(pd);
2890         pkt_debugfs_dev_new(pd);
2891
2892         pkt_devs[idx] = pd;
2893         if (pkt_dev)
2894                 *pkt_dev = pd->pkt_dev;
2895
2896         mutex_unlock(&ctl_mutex);
2897         return 0;
2898
2899 out_new_dev:
2900         blk_cleanup_queue(disk->queue);
2901 out_mem2:
2902         put_disk(disk);
2903 out_mem:
2904         if (pd->rb_pool)
2905                 mempool_destroy(pd->rb_pool);
2906         kfree(pd);
2907 out_mutex:
2908         mutex_unlock(&ctl_mutex);
2909         printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2910         return ret;
2911 }
2912
2913 /*
2914  * Tear down mapping from pktcdvd device to CD-ROM device.
2915  */
2916 static int pkt_remove_dev(dev_t pkt_dev)
2917 {
2918         struct pktcdvd_device *pd;
2919         int idx;
2920         int ret = 0;
2921
2922         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2923
2924         for (idx = 0; idx < MAX_WRITERS; idx++) {
2925                 pd = pkt_devs[idx];
2926                 if (pd && (pd->pkt_dev == pkt_dev))
2927                         break;
2928         }
2929         if (idx == MAX_WRITERS) {
2930                 DPRINTK(DRIVER_NAME": dev not setup\n");
2931                 ret = -ENXIO;
2932                 goto out;
2933         }
2934
2935         if (pd->refcnt > 0) {
2936                 ret = -EBUSY;
2937                 goto out;
2938         }
2939         if (!IS_ERR(pd->cdrw.thread))
2940                 kthread_stop(pd->cdrw.thread);
2941
2942         pkt_devs[idx] = NULL;
2943
2944         pkt_debugfs_dev_remove(pd);
2945         pkt_sysfs_dev_remove(pd);
2946
2947         blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2948
2949         remove_proc_entry(pd->name, pkt_proc);
2950         DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2951
2952         del_gendisk(pd->disk);
2953         blk_cleanup_queue(pd->disk->queue);
2954         put_disk(pd->disk);
2955
2956         mempool_destroy(pd->rb_pool);
2957         kfree(pd);
2958
2959         /* This is safe: open() is still holding a reference. */
2960         module_put(THIS_MODULE);
2961
2962 out:
2963         mutex_unlock(&ctl_mutex);
2964         return ret;
2965 }
2966
2967 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2968 {
2969         struct pktcdvd_device *pd;
2970
2971         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2972
2973         pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2974         if (pd) {
2975                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2976                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2977         } else {
2978                 ctrl_cmd->dev = 0;
2979                 ctrl_cmd->pkt_dev = 0;
2980         }
2981         ctrl_cmd->num_devices = MAX_WRITERS;
2982
2983         mutex_unlock(&ctl_mutex);
2984 }
2985
2986 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2987 {
2988         void __user *argp = (void __user *)arg;
2989         struct pkt_ctrl_command ctrl_cmd;
2990         int ret = 0;
2991         dev_t pkt_dev = 0;
2992
2993         if (cmd != PACKET_CTRL_CMD)
2994                 return -ENOTTY;
2995
2996         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2997                 return -EFAULT;
2998
2999         switch (ctrl_cmd.command) {
3000         case PKT_CTRL_CMD_SETUP:
3001                 if (!capable(CAP_SYS_ADMIN))
3002                         return -EPERM;
3003                 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
3004                 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
3005                 break;
3006         case PKT_CTRL_CMD_TEARDOWN:
3007                 if (!capable(CAP_SYS_ADMIN))
3008                         return -EPERM;
3009                 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
3010                 break;
3011         case PKT_CTRL_CMD_STATUS:
3012                 pkt_get_status(&ctrl_cmd);
3013                 break;
3014         default:
3015                 return -ENOTTY;
3016         }
3017
3018         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
3019                 return -EFAULT;
3020         return ret;
3021 }
3022
3023
3024 static const struct file_operations pkt_ctl_fops = {
3025         .ioctl   = pkt_ctl_ioctl,
3026         .owner   = THIS_MODULE,
3027 };
3028
3029 static struct miscdevice pkt_misc = {
3030         .minor          = MISC_DYNAMIC_MINOR,
3031         .name           = DRIVER_NAME,
3032         .nodename       = "pktcdvd/control",
3033         .fops           = &pkt_ctl_fops
3034 };
3035
3036 static int __init pkt_init(void)
3037 {
3038         int ret;
3039
3040         mutex_init(&ctl_mutex);
3041
3042         psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
3043                                         sizeof(struct packet_stacked_data));
3044         if (!psd_pool)
3045                 return -ENOMEM;
3046
3047         ret = register_blkdev(pktdev_major, DRIVER_NAME);
3048         if (ret < 0) {
3049                 printk(DRIVER_NAME": Unable to register block device\n");
3050                 goto out2;
3051         }
3052         if (!pktdev_major)
3053                 pktdev_major = ret;
3054
3055         ret = pkt_sysfs_init();
3056         if (ret)
3057                 goto out;
3058
3059         pkt_debugfs_init();
3060
3061         ret = misc_register(&pkt_misc);
3062         if (ret) {
3063                 printk(DRIVER_NAME": Unable to register misc device\n");
3064                 goto out_misc;
3065         }
3066
3067         pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
3068
3069         return 0;
3070
3071 out_misc:
3072         pkt_debugfs_cleanup();
3073         pkt_sysfs_cleanup();
3074 out:
3075         unregister_blkdev(pktdev_major, DRIVER_NAME);
3076 out2:
3077         mempool_destroy(psd_pool);
3078         return ret;
3079 }
3080
3081 static void __exit pkt_exit(void)
3082 {
3083         remove_proc_entry("driver/"DRIVER_NAME, NULL);
3084         misc_deregister(&pkt_misc);
3085
3086         pkt_debugfs_cleanup();
3087         pkt_sysfs_cleanup();
3088
3089         unregister_blkdev(pktdev_major, DRIVER_NAME);
3090         mempool_destroy(psd_pool);
3091 }
3092
3093 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3094 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3095 MODULE_LICENSE("GPL");
3096
3097 module_init(pkt_init);
3098 module_exit(pkt_exit);