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; /* /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         p = kzalloc(sizeof(*p), GFP_KERNEL);
 114         if (!p)
 115                 return NULL;
 116         kobject_set_name(&p->kobj, "%s", name);
 117         p->kobj.parent = parent;
 118         p->kobj.ktype = ktype;
 119         p->pd = pd;
 120         if (kobject_register(&p->kobj) != 0)
 121                 return NULL;
 122         return p;
 123 }
 124 /*
 125  * remove a pktcdvd kernel object.
 126  */
 127 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 128 {
 129         if (p)
 130                 kobject_unregister(&p->kobj);
 131 }
 132 /*
 133  * default release function for pktcdvd kernel objects.
 134  */
 135 static void pkt_kobj_release(struct kobject *kobj)
 136 {
 137         kfree(to_pktcdvdkobj(kobj));
 138 }
 139
 140
 141 /**********************************************************
 142  *
 143  * sysfs interface for pktcdvd
 144  * by (C) 2006  Thomas Maier <balagi@justmail.de>
 145  *
 146  **********************************************************/
 147
 148 #define DEF_ATTR(_obj,_name,_mode) \
 149         static struct attribute _obj = { .name = _name, .mode = _mode }
 150
 151 /**********************************************************
 152   /sys/class/pktcdvd/pktcdvd[0-7]/
 153                      stat/reset
 154                      stat/packets_started
 155                      stat/packets_finished
 156                      stat/kb_written
 157                      stat/kb_read
 158                      stat/kb_read_gather
 159                      write_queue/size
 160                      write_queue/congestion_off
 161                      write_queue/congestion_on
 162  **********************************************************/
 163
 164 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 165 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 166 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 167 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 168 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 169 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 170
 171 static struct attribute *kobj_pkt_attrs_stat[] = {
 172         &kobj_pkt_attr_st1,
 173         &kobj_pkt_attr_st2,
 174         &kobj_pkt_attr_st3,
 175         &kobj_pkt_attr_st4,
 176         &kobj_pkt_attr_st5,
 177         &kobj_pkt_attr_st6,
 178         NULL
 179 };
 180
 181 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 182 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 183 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 184
 185 static struct attribute *kobj_pkt_attrs_wqueue[] = {
 186         &kobj_pkt_attr_wq1,
 187         &kobj_pkt_attr_wq2,
 188         &kobj_pkt_attr_wq3,
 189         NULL
 190 };
 191
 192 static ssize_t kobj_pkt_show(struct kobject *kobj,
 193                         struct attribute *attr, char *data)
 194 {
 195         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 196         int n = 0;
 197         int v;
 198         if (strcmp(attr->name, "packets_started") == 0) {
 199                 n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 200
 201         } else if (strcmp(attr->name, "packets_finished") == 0) {
 202                 n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 203
 204         } else if (strcmp(attr->name, "kb_written") == 0) {
 205                 n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 206
 207         } else if (strcmp(attr->name, "kb_read") == 0) {
 208                 n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 209
 210         } else if (strcmp(attr->name, "kb_read_gather") == 0) {
 211                 n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 212
 213         } else if (strcmp(attr->name, "size") == 0) {
 214                 spin_lock(&pd->lock);
 215                 v = pd->bio_queue_size;
 216                 spin_unlock(&pd->lock);
 217                 n = sprintf(data, "%d\n", v);
 218
 219         } else if (strcmp(attr->name, "congestion_off") == 0) {
 220                 spin_lock(&pd->lock);
 221                 v = pd->write_congestion_off;
 222                 spin_unlock(&pd->lock);
 223                 n = sprintf(data, "%d\n", v);
 224
 225         } else if (strcmp(attr->name, "congestion_on") == 0) {
 226                 spin_lock(&pd->lock);
 227                 v = pd->write_congestion_on;
 228                 spin_unlock(&pd->lock);
 229                 n = sprintf(data, "%d\n", v);
 230         }
 231         return n;
 232 }
 233
 234 static void init_write_congestion_marks(int* lo, int* hi)
 235 {
 236         if (*hi > 0) {
 237                 *hi = max(*hi, 500);
 238                 *hi = min(*hi, 1000000);
 239                 if (*lo <= 0)
 240                         *lo = *hi - 100;
 241                 else {
 242                         *lo = min(*lo, *hi - 100);
 243                         *lo = max(*lo, 100);
 244                 }
 245         } else {
 246                 *hi = -1;
 247                 *lo = -1;
 248         }
 249 }
 250
 251 static ssize_t kobj_pkt_store(struct kobject *kobj,
 252                         struct attribute *attr,
 253                         const char *data, size_t len)
 254 {
 255         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 256         int val;
 257
 258         if (strcmp(attr->name, "reset") == 0 && len > 0) {
 259                 pd->stats.pkt_started = 0;
 260                 pd->stats.pkt_ended = 0;
 261                 pd->stats.secs_w = 0;
 262                 pd->stats.secs_rg = 0;
 263                 pd->stats.secs_r = 0;
 264
 265         } else if (strcmp(attr->name, "congestion_off") == 0
 266                    && sscanf(data, "%d", &val) == 1) {
 267                 spin_lock(&pd->lock);
 268                 pd->write_congestion_off = val;
 269                 init_write_congestion_marks(&pd->write_congestion_off,
 270                                         &pd->write_congestion_on);
 271                 spin_unlock(&pd->lock);
 272
 273         } else if (strcmp(attr->name, "congestion_on") == 0
 274                    && sscanf(data, "%d", &val) == 1) {
 275                 spin_lock(&pd->lock);
 276                 pd->write_congestion_on = val;
 277                 init_write_congestion_marks(&pd->write_congestion_off,
 278                                         &pd->write_congestion_on);
 279                 spin_unlock(&pd->lock);
 280         }
 281         return len;
 282 }
 283
 284 static struct sysfs_ops kobj_pkt_ops = {
 285         .show = kobj_pkt_show,
 286         .store = kobj_pkt_store
 287 };
 288 static struct kobj_type kobj_pkt_type_stat = {
 289         .release = pkt_kobj_release,
 290         .sysfs_ops = &kobj_pkt_ops,
 291         .default_attrs = kobj_pkt_attrs_stat
 292 };
 293 static struct kobj_type kobj_pkt_type_wqueue = {
 294         .release = pkt_kobj_release,
 295         .sysfs_ops = &kobj_pkt_ops,
 296         .default_attrs = kobj_pkt_attrs_wqueue
 297 };
 298
 299 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 300 {
 301         if (class_pktcdvd) {
 302                 pd->clsdev = class_device_create(class_pktcdvd,
 303                                         NULL, pd->pkt_dev,
 304                                         NULL, "%s", pd->name);
 305                 if (IS_ERR(pd->clsdev))
 306                         pd->clsdev = NULL;
 307         }
 308         if (pd->clsdev) {
 309                 pd->kobj_stat = pkt_kobj_create(pd, "stat",
 310                                         &pd->clsdev->kobj,
 311                                         &kobj_pkt_type_stat);
 312                 pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 313                                         &pd->clsdev->kobj,
 314                                         &kobj_pkt_type_wqueue);
 315         }
 316 }
 317
 318 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 319 {
 320         pkt_kobj_remove(pd->kobj_stat);
 321         pkt_kobj_remove(pd->kobj_wqueue);
 322         if (class_pktcdvd)
 323                 class_device_destroy(class_pktcdvd, pd->pkt_dev);
 324 }
 325
 326
 327 /********************************************************************
 328   /sys/class/pktcdvd/
 329                      add            map block device
 330                      remove         unmap packet dev
 331                      device_map     show mappings
 332  *******************************************************************/
 333
 334 static void class_pktcdvd_release(struct class *cls)
 335 {
 336         kfree(cls);
 337 }
 338 static ssize_t class_pktcdvd_show_map(struct class *c, char *data)
 339 {
 340         int n = 0;
 341         int idx;
 342         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 343         for (idx = 0; idx < MAX_WRITERS; idx++) {
 344                 struct pktcdvd_device *pd = pkt_devs[idx];
 345                 if (!pd)
 346                         continue;
 347                 n += sprintf(data+n, "%s %u:%u %u:%u\n",
 348                         pd->name,
 349                         MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 350                         MAJOR(pd->bdev->bd_dev),
 351                         MINOR(pd->bdev->bd_dev));
 352         }
 353         mutex_unlock(&ctl_mutex);
 354         return n;
 355 }
 356
 357 static ssize_t class_pktcdvd_store_add(struct class *c, const char *buf,
 358                                         size_t count)
 359 {
 360         unsigned int major, minor;
 361         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 362                 pkt_setup_dev(MKDEV(major, minor), NULL);
 363                 return count;
 364         }
 365         return -EINVAL;
 366 }
 367
 368 static ssize_t class_pktcdvd_store_remove(struct class *c, const char *buf,
 369                                         size_t count)
 370 {
 371         unsigned int major, minor;
 372         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 373                 pkt_remove_dev(MKDEV(major, minor));
 374                 return count;
 375         }
 376         return -EINVAL;
 377 }
 378
 379 static struct class_attribute class_pktcdvd_attrs[] = {
 380  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 381  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 382  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 383  __ATTR_NULL
 384 };
 385
 386
 387 static int pkt_sysfs_init(void)
 388 {
 389         int ret = 0;
 390
 391         /*
 392          * create control files in sysfs
 393          * /sys/class/pktcdvd/...
 394          */
 395         class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 396         if (!class_pktcdvd)
 397                 return -ENOMEM;
 398         class_pktcdvd->name = DRIVER_NAME;
 399         class_pktcdvd->owner = THIS_MODULE;
 400         class_pktcdvd->class_release = class_pktcdvd_release;
 401         class_pktcdvd->class_attrs = class_pktcdvd_attrs;
 402         ret = class_register(class_pktcdvd);
 403         if (ret) {
 404                 kfree(class_pktcdvd);
 405                 class_pktcdvd = NULL;
 406                 printk(DRIVER_NAME": failed to create class pktcdvd\n");
 407                 return ret;
 408         }
 409         return 0;
 410 }
 411
 412 static void pkt_sysfs_cleanup(void)
 413 {
 414         if (class_pktcdvd)
 415                 class_destroy(class_pktcdvd);
 416         class_pktcdvd = NULL;
 417 }
 418
 419 /********************************************************************
 420   entries in debugfs
 421
 422   /debugfs/pktcdvd[0-7]/
 423                         info
 424
 425  *******************************************************************/
 426
 427 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 428 {
 429         return pkt_seq_show(m, p);
 430 }
 431
 432 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 433 {
 434         return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 435 }
 436
 437 static const struct file_operations debug_fops = {
 438         .open           = pkt_debugfs_fops_open,
 439         .read           = seq_read,
 440         .llseek         = seq_lseek,
 441         .release        = single_release,
 442         .owner          = THIS_MODULE,
 443 };
 444
 445 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 446 {
 447         if (!pkt_debugfs_root)
 448                 return;
 449         pd->dfs_f_info = NULL;
 450         pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 451         if (IS_ERR(pd->dfs_d_root)) {
 452                 pd->dfs_d_root = NULL;
 453                 return;
 454         }
 455         pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
 456                                 pd->dfs_d_root, pd, &debug_fops);
 457         if (IS_ERR(pd->dfs_f_info)) {
 458                 pd->dfs_f_info = NULL;
 459                 return;
 460         }
 461 }
 462
 463 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 464 {
 465         if (!pkt_debugfs_root)
 466                 return;
 467         if (pd->dfs_f_info)
 468                 debugfs_remove(pd->dfs_f_info);
 469         pd->dfs_f_info = NULL;
 470         if (pd->dfs_d_root)
 471                 debugfs_remove(pd->dfs_d_root);
 472         pd->dfs_d_root = NULL;
 473 }
 474
 475 static void pkt_debugfs_init(void)
 476 {
 477         pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 478         if (IS_ERR(pkt_debugfs_root)) {
 479                 pkt_debugfs_root = NULL;
 480                 return;
 481         }
 482 }
 483
 484 static void pkt_debugfs_cleanup(void)
 485 {
 486         if (!pkt_debugfs_root)
 487                 return;
 488         debugfs_remove(pkt_debugfs_root);
 489         pkt_debugfs_root = NULL;
 490 }
 491
 492 /* ----------------------------------------------------------*/
 493
 494
 495 static void pkt_bio_finished(struct pktcdvd_device *pd)
 496 {
 497         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 498         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 499                 VPRINTK(DRIVER_NAME": queue empty\n");
 500                 atomic_set(&pd->iosched.attention, 1);
 501                 wake_up(&pd->wqueue);
 502         }
 503 }
 504
 505 static void pkt_bio_destructor(struct bio *bio)
 506 {
 507         kfree(bio->bi_io_vec);
 508         kfree(bio);
 509 }
 510
 511 static struct bio *pkt_bio_alloc(int nr_iovecs)
 512 {
 513         struct bio_vec *bvl = NULL;
 514         struct bio *bio;
 515
 516         bio = kmalloc(sizeof(struct bio), GFP_KERNEL);
 517         if (!bio)
 518                 goto no_bio;
 519         bio_init(bio);
 520
 521         bvl = kcalloc(nr_iovecs, sizeof(struct bio_vec), GFP_KERNEL);
 522         if (!bvl)
 523                 goto no_bvl;
 524
 525         bio->bi_max_vecs = nr_iovecs;
 526         bio->bi_io_vec = bvl;
 527         bio->bi_destructor = pkt_bio_destructor;
 528
 529         return bio;
 530
 531  no_bvl:
 532         kfree(bio);
 533  no_bio:
 534         return NULL;
 535 }
 536
 537 /*
 538  * Allocate a packet_data struct
 539  */
 540 static struct packet_data *pkt_alloc_packet_data(int frames)
 541 {
 542         int i;
 543         struct packet_data *pkt;
 544
 545         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 546         if (!pkt)
 547                 goto no_pkt;
 548
 549         pkt->frames = frames;
 550         pkt->w_bio = pkt_bio_alloc(frames);
 551         if (!pkt->w_bio)
 552                 goto no_bio;
 553
 554         for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 555                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 556                 if (!pkt->pages[i])
 557                         goto no_page;
 558         }
 559
 560         spin_lock_init(&pkt->lock);
 561
 562         for (i = 0; i < frames; i++) {
 563                 struct bio *bio = pkt_bio_alloc(1);
 564                 if (!bio)
 565                         goto no_rd_bio;
 566                 pkt->r_bios[i] = bio;
 567         }
 568
 569         return pkt;
 570
 571 no_rd_bio:
 572         for (i = 0; i < frames; i++) {
 573                 struct bio *bio = pkt->r_bios[i];
 574                 if (bio)
 575                         bio_put(bio);
 576         }
 577
 578 no_page:
 579         for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 580                 if (pkt->pages[i])
 581                         __free_page(pkt->pages[i]);
 582         bio_put(pkt->w_bio);
 583 no_bio:
 584         kfree(pkt);
 585 no_pkt:
 586         return NULL;
 587 }
 588
 589 /*
 590  * Free a packet_data struct
 591  */
 592 static void pkt_free_packet_data(struct packet_data *pkt)
 593 {
 594         int i;
 595
 596         for (i = 0; i < pkt->frames; i++) {
 597                 struct bio *bio = pkt->r_bios[i];
 598                 if (bio)
 599                         bio_put(bio);
 600         }
 601         for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 602                 __free_page(pkt->pages[i]);
 603         bio_put(pkt->w_bio);
 604         kfree(pkt);
 605 }
 606
 607 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 608 {
 609         struct packet_data *pkt, *next;
 610
 611         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 612
 613         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 614                 pkt_free_packet_data(pkt);
 615         }
 616         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 617 }
 618
 619 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 620 {
 621         struct packet_data *pkt;
 622
 623         BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 624
 625         while (nr_packets > 0) {
 626                 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 627                 if (!pkt) {
 628                         pkt_shrink_pktlist(pd);
 629                         return 0;
 630                 }
 631                 pkt->id = nr_packets;
 632                 pkt->pd = pd;
 633                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 634                 nr_packets--;
 635         }
 636         return 1;
 637 }
 638
 639 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 640 {
 641         struct rb_node *n = rb_next(&node->rb_node);
 642         if (!n)
 643                 return NULL;
 644         return rb_entry(n, struct pkt_rb_node, rb_node);
 645 }
 646
 647 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 648 {
 649         rb_erase(&node->rb_node, &pd->bio_queue);
 650         mempool_free(node, pd->rb_pool);
 651         pd->bio_queue_size--;
 652         BUG_ON(pd->bio_queue_size < 0);
 653 }
 654
 655 /*
 656  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 657  */
 658 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 659 {
 660         struct rb_node *n = pd->bio_queue.rb_node;
 661         struct rb_node *next;
 662         struct pkt_rb_node *tmp;
 663
 664         if (!n) {
 665                 BUG_ON(pd->bio_queue_size > 0);
 666                 return NULL;
 667         }
 668
 669         for (;;) {
 670                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 671                 if (s <= tmp->bio->bi_sector)
 672                         next = n->rb_left;
 673                 else
 674                         next = n->rb_right;
 675                 if (!next)
 676                         break;
 677                 n = next;
 678         }
 679
 680         if (s > tmp->bio->bi_sector) {
 681                 tmp = pkt_rbtree_next(tmp);
 682                 if (!tmp)
 683                         return NULL;
 684         }
 685         BUG_ON(s > tmp->bio->bi_sector);
 686         return tmp;
 687 }
 688
 689 /*
 690  * Insert a node into the pd->bio_queue rb tree.
 691  */
 692 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 693 {
 694         struct rb_node **p = &pd->bio_queue.rb_node;
 695         struct rb_node *parent = NULL;
 696         sector_t s = node->bio->bi_sector;
 697         struct pkt_rb_node *tmp;
 698
 699         while (*p) {
 700                 parent = *p;
 701                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 702                 if (s < tmp->bio->bi_sector)
 703                         p = &(*p)->rb_left;
 704                 else
 705                         p = &(*p)->rb_right;
 706         }
 707         rb_link_node(&node->rb_node, parent, p);
 708         rb_insert_color(&node->rb_node, &pd->bio_queue);
 709         pd->bio_queue_size++;
 710 }
 711
 712 /*
 713  * Add a bio to a single linked list defined by its head and tail pointers.
 714  */
 715 static void pkt_add_list_last(struct bio *bio, struct bio **list_head, struct bio **list_tail)
 716 {
 717         bio->bi_next = NULL;
 718         if (*list_tail) {
 719                 BUG_ON((*list_head) == NULL);
 720                 (*list_tail)->bi_next = bio;
 721                 (*list_tail) = bio;
 722         } else {
 723                 BUG_ON((*list_head) != NULL);
 724                 (*list_head) = bio;
 725                 (*list_tail) = bio;
 726         }
 727 }
 728
 729 /*
 730  * Remove and return the first bio from a single linked list defined by its
 731  * head and tail pointers.
 732  */
 733 static inline struct bio *pkt_get_list_first(struct bio **list_head, struct bio **list_tail)
 734 {
 735         struct bio *bio;
 736
 737         if (*list_head == NULL)
 738                 return NULL;
 739
 740         bio = *list_head;
 741         *list_head = bio->bi_next;
 742         if (*list_head == NULL)
 743                 *list_tail = NULL;
 744
 745         bio->bi_next = NULL;
 746         return bio;
 747 }
 748
 749 /*
 750  * Send a packet_command to the underlying block device and
 751  * wait for completion.
 752  */
 753 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 754 {
 755         struct request_queue *q = bdev_get_queue(pd->bdev);
 756         struct request *rq;
 757         int ret = 0;
 758
 759         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 760                              WRITE : READ, __GFP_WAIT);
 761
 762         if (cgc->buflen) {
 763                 if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
 764                         goto out;
 765         }
 766
 767         rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 768         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 769         if (sizeof(rq->cmd) > CDROM_PACKET_SIZE)
 770                 memset(rq->cmd + CDROM_PACKET_SIZE, 0, sizeof(rq->cmd) - CDROM_PACKET_SIZE);
 771
 772         rq->timeout = 60*HZ;
 773         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 774         rq->cmd_flags |= REQ_HARDBARRIER;
 775         if (cgc->quiet)
 776                 rq->cmd_flags |= REQ_QUIET;
 777
 778         blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 779         if (rq->errors)
 780                 ret = -EIO;
 781 out:
 782         blk_put_request(rq);
 783         return ret;
 784 }
 785
 786 /*
 787  * A generic sense dump / resolve mechanism should be implemented across
 788  * all ATAPI + SCSI devices.
 789  */
 790 static void pkt_dump_sense(struct packet_command *cgc)
 791 {
 792         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 793                                  "Medium error", "Hardware error", "Illegal request",
 794                                  "Unit attention", "Data protect", "Blank check" };
 795         int i;
 796         struct request_sense *sense = cgc->sense;
 797
 798         printk(DRIVER_NAME":");
 799         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 800                 printk(" %02x", cgc->cmd[i]);
 801         printk(" - ");
 802
 803         if (sense == NULL) {
 804                 printk("no sense\n");
 805                 return;
 806         }
 807
 808         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 809
 810         if (sense->sense_key > 8) {
 811                 printk(" (INVALID)\n");
 812                 return;
 813         }
 814
 815         printk(" (%s)\n", info[sense->sense_key]);
 816 }
 817
 818 /*
 819  * flush the drive cache to media
 820  */
 821 static int pkt_flush_cache(struct pktcdvd_device *pd)
 822 {
 823         struct packet_command cgc;
 824
 825         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 826         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 827         cgc.quiet = 1;
 828
 829         /*
 830          * the IMMED bit -- we default to not setting it, although that
 831          * would allow a much faster close, this is safer
 832          */
 833 #if 0
 834         cgc.cmd[1] = 1 << 1;
 835 #endif
 836         return pkt_generic_packet(pd, &cgc);
 837 }
 838
 839 /*
 840  * speed is given as the normal factor, e.g. 4 for 4x
 841  */
 842 static int pkt_set_speed(struct pktcdvd_device *pd, unsigned write_speed, unsigned read_speed)
 843 {
 844         struct packet_command cgc;
 845         struct request_sense sense;
 846         int ret;
 847
 848         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 849         cgc.sense = &sense;
 850         cgc.cmd[0] = GPCMD_SET_SPEED;
 851         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 852         cgc.cmd[3] = read_speed & 0xff;
 853         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 854         cgc.cmd[5] = write_speed & 0xff;
 855
 856         if ((ret = pkt_generic_packet(pd, &cgc)))
 857                 pkt_dump_sense(&cgc);
 858
 859         return ret;
 860 }
 861
 862 /*
 863  * Queue a bio for processing by the low-level CD device. Must be called
 864  * from process context.
 865  */
 866 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 867 {
 868         spin_lock(&pd->iosched.lock);
 869         if (bio_data_dir(bio) == READ) {
 870                 pkt_add_list_last(bio, &pd->iosched.read_queue,
 871                                   &pd->iosched.read_queue_tail);
 872         } else {
 873                 pkt_add_list_last(bio, &pd->iosched.write_queue,
 874                                   &pd->iosched.write_queue_tail);
 875         }
 876         spin_unlock(&pd->iosched.lock);
 877
 878         atomic_set(&pd->iosched.attention, 1);
 879         wake_up(&pd->wqueue);
 880 }
 881
 882 /*
 883  * Process the queued read/write requests. This function handles special
 884  * requirements for CDRW drives:
 885  * - A cache flush command must be inserted before a read request if the
 886  *   previous request was a write.
 887  * - Switching between reading and writing is slow, so don't do it more often
 888  *   than necessary.
 889  * - Optimize for throughput at the expense of latency. This means that streaming
 890  *   writes will never be interrupted by a read, but if the drive has to seek
 891  *   before the next write, switch to reading instead if there are any pending
 892  *   read requests.
 893  * - Set the read speed according to current usage pattern. When only reading
 894  *   from the device, it's best to use the highest possible read speed, but
 895  *   when switching often between reading and writing, it's better to have the
 896  *   same read and write speeds.
 897  */
 898 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 899 {
 900
 901         if (atomic_read(&pd->iosched.attention) == 0)
 902                 return;
 903         atomic_set(&pd->iosched.attention, 0);
 904
 905         for (;;) {
 906                 struct bio *bio;
 907                 int reads_queued, writes_queued;
 908
 909                 spin_lock(&pd->iosched.lock);
 910                 reads_queued = (pd->iosched.read_queue != NULL);
 911                 writes_queued = (pd->iosched.write_queue != NULL);
 912                 spin_unlock(&pd->iosched.lock);
 913
 914                 if (!reads_queued && !writes_queued)
 915                         break;
 916
 917                 if (pd->iosched.writing) {
 918                         int need_write_seek = 1;
 919                         spin_lock(&pd->iosched.lock);
 920                         bio = pd->iosched.write_queue;
 921                         spin_unlock(&pd->iosched.lock);
 922                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 923                                 need_write_seek = 0;
 924                         if (need_write_seek && reads_queued) {
 925                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 926                                         VPRINTK(DRIVER_NAME": write, waiting\n");
 927                                         break;
 928                                 }
 929                                 pkt_flush_cache(pd);
 930                                 pd->iosched.writing = 0;
 931                         }
 932                 } else {
 933                         if (!reads_queued && writes_queued) {
 934                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 935                                         VPRINTK(DRIVER_NAME": read, waiting\n");
 936                                         break;
 937                                 }
 938                                 pd->iosched.writing = 1;
 939                         }
 940                 }
 941
 942                 spin_lock(&pd->iosched.lock);
 943                 if (pd->iosched.writing) {
 944                         bio = pkt_get_list_first(&pd->iosched.write_queue,
 945                                                  &pd->iosched.write_queue_tail);
 946                 } else {
 947                         bio = pkt_get_list_first(&pd->iosched.read_queue,
 948                                                  &pd->iosched.read_queue_tail);
 949                 }
 950                 spin_unlock(&pd->iosched.lock);
 951
 952                 if (!bio)
 953                         continue;
 954
 955                 if (bio_data_dir(bio) == READ)
 956                         pd->iosched.successive_reads += bio->bi_size >> 10;
 957                 else {
 958                         pd->iosched.successive_reads = 0;
 959                         pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
 960                 }
 961                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 962                         if (pd->read_speed == pd->write_speed) {
 963                                 pd->read_speed = MAX_SPEED;
 964                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 965                         }
 966                 } else {
 967                         if (pd->read_speed != pd->write_speed) {
 968                                 pd->read_speed = pd->write_speed;
 969                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 970                         }
 971                 }
 972
 973                 atomic_inc(&pd->cdrw.pending_bios);
 974                 generic_make_request(bio);
 975         }
 976 }
 977
 978 /*
 979  * Special care is needed if the underlying block device has a small
 980  * max_phys_segments value.
 981  */
 982 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 983 {
 984         if ((pd->settings.size << 9) / CD_FRAMESIZE <= q->max_phys_segments) {
 985                 /*
 986                  * The cdrom device can handle one segment/frame
 987                  */
 988                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 989                 return 0;
 990         } else if ((pd->settings.size << 9) / PAGE_SIZE <= q->max_phys_segments) {
 991                 /*
 992                  * We can handle this case at the expense of some extra memory
 993                  * copies during write operations
 994                  */
 995                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 996                 return 0;
 997         } else {
 998                 printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
 999                 return -EIO;
1000         }
1001 }
1002
1003 /*
1004  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
1005  */
1006 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
1007 {
1008         unsigned int copy_size = CD_FRAMESIZE;
1009
1010         while (copy_size > 0) {
1011                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
1012                 void *vfrom = kmap_atomic(src_bvl->bv_page, KM_USER0) +
1013                         src_bvl->bv_offset + offs;
1014                 void *vto = page_address(dst_page) + dst_offs;
1015                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
1016
1017                 BUG_ON(len < 0);
1018                 memcpy(vto, vfrom, len);
1019                 kunmap_atomic(vfrom, KM_USER0);
1020
1021                 seg++;
1022                 offs = 0;
1023                 dst_offs += len;
1024                 copy_size -= len;
1025         }
1026 }
1027
1028 /*
1029  * Copy all data for this packet to pkt->pages[], so that
1030  * a) The number of required segments for the write bio is minimized, which
1031  *    is necessary for some scsi controllers.
1032  * b) The data can be used as cache to avoid read requests if we receive a
1033  *    new write request for the same zone.
1034  */
1035 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
1036 {
1037         int f, p, offs;
1038
1039         /* Copy all data to pkt->pages[] */
1040         p = 0;
1041         offs = 0;
1042         for (f = 0; f < pkt->frames; f++) {
1043                 if (bvec[f].bv_page != pkt->pages[p]) {
1044                         void *vfrom = kmap_atomic(bvec[f].bv_page, KM_USER0) + bvec[f].bv_offset;
1045                         void *vto = page_address(pkt->pages[p]) + offs;
1046                         memcpy(vto, vfrom, CD_FRAMESIZE);
1047                         kunmap_atomic(vfrom, KM_USER0);
1048                         bvec[f].bv_page = pkt->pages[p];
1049                         bvec[f].bv_offset = offs;
1050                 } else {
1051                         BUG_ON(bvec[f].bv_offset != offs);
1052                 }
1053                 offs += CD_FRAMESIZE;
1054                 if (offs >= PAGE_SIZE) {
1055                         offs = 0;
1056                         p++;
1057                 }
1058         }
1059 }
1060
1061 static void pkt_end_io_read(struct bio *bio, int err)
1062 {
1063         struct packet_data *pkt = bio->bi_private;
1064         struct pktcdvd_device *pd = pkt->pd;
1065         BUG_ON(!pd);
1066
1067         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
1068                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
1069
1070         if (err)
1071                 atomic_inc(&pkt->io_errors);
1072         if (atomic_dec_and_test(&pkt->io_wait)) {
1073                 atomic_inc(&pkt->run_sm);
1074                 wake_up(&pd->wqueue);
1075         }
1076         pkt_bio_finished(pd);
1077 }
1078
1079 static void pkt_end_io_packet_write(struct bio *bio, int err)
1080 {
1081         struct packet_data *pkt = bio->bi_private;
1082         struct pktcdvd_device *pd = pkt->pd;
1083         BUG_ON(!pd);
1084
1085         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1086
1087         pd->stats.pkt_ended++;
1088
1089         pkt_bio_finished(pd);
1090         atomic_dec(&pkt->io_wait);
1091         atomic_inc(&pkt->run_sm);
1092         wake_up(&pd->wqueue);
1093 }
1094
1095 /*
1096  * Schedule reads for the holes in a packet
1097  */
1098 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1099 {
1100         int frames_read = 0;
1101         struct bio *bio;
1102         int f;
1103         char written[PACKET_MAX_SIZE];
1104
1105         BUG_ON(!pkt->orig_bios);
1106
1107         atomic_set(&pkt->io_wait, 0);
1108         atomic_set(&pkt->io_errors, 0);
1109
1110         /*
1111          * Figure out which frames we need to read before we can write.
1112          */
1113         memset(written, 0, sizeof(written));
1114         spin_lock(&pkt->lock);
1115         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1116                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1117                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1118                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1119                 BUG_ON(first_frame < 0);
1120                 BUG_ON(first_frame + num_frames > pkt->frames);
1121                 for (f = first_frame; f < first_frame + num_frames; f++)
1122                         written[f] = 1;
1123         }
1124         spin_unlock(&pkt->lock);
1125
1126         if (pkt->cache_valid) {
1127                 VPRINTK("pkt_gather_data: zone %llx cached\n",
1128                         (unsigned long long)pkt->sector);
1129                 goto out_account;
1130         }
1131
1132         /*
1133          * Schedule reads for missing parts of the packet.
1134          */
1135         for (f = 0; f < pkt->frames; f++) {
1136                 struct bio_vec *vec;
1137
1138                 int p, offset;
1139                 if (written[f])
1140                         continue;
1141                 bio = pkt->r_bios[f];
1142                 vec = bio->bi_io_vec;
1143                 bio_init(bio);
1144                 bio->bi_max_vecs = 1;
1145                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1146                 bio->bi_bdev = pd->bdev;
1147                 bio->bi_end_io = pkt_end_io_read;
1148                 bio->bi_private = pkt;
1149                 bio->bi_io_vec = vec;
1150
1151                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1152                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1153                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1154                         f, pkt->pages[p], offset);
1155                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1156                         BUG();
1157
1158                 atomic_inc(&pkt->io_wait);
1159                 bio->bi_rw = READ;
1160                 pkt_queue_bio(pd, bio);
1161                 frames_read++;
1162         }
1163
1164 out_account:
1165         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1166                 frames_read, (unsigned long long)pkt->sector);
1167         pd->stats.pkt_started++;
1168         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1169 }
1170
1171 /*
1172  * Find a packet matching zone, or the least recently used packet if
1173  * there is no match.
1174  */
1175 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1176 {
1177         struct packet_data *pkt;
1178
1179         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1180                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1181                         list_del_init(&pkt->list);
1182                         if (pkt->sector != zone)
1183                                 pkt->cache_valid = 0;
1184                         return pkt;
1185                 }
1186         }
1187         BUG();
1188         return NULL;
1189 }
1190
1191 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1192 {
1193         if (pkt->cache_valid) {
1194                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1195         } else {
1196                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1197         }
1198 }
1199
1200 /*
1201  * recover a failed write, query for relocation if possible
1202  *
1203  * returns 1 if recovery is possible, or 0 if not
1204  *
1205  */
1206 static int pkt_start_recovery(struct packet_data *pkt)
1207 {
1208         /*
1209          * FIXME. We need help from the file system to implement
1210          * recovery handling.
1211          */
1212         return 0;
1213 #if 0
1214         struct request *rq = pkt->rq;
1215         struct pktcdvd_device *pd = rq->rq_disk->private_data;
1216         struct block_device *pkt_bdev;
1217         struct super_block *sb = NULL;
1218         unsigned long old_block, new_block;
1219         sector_t new_sector;
1220
1221         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1222         if (pkt_bdev) {
1223                 sb = get_super(pkt_bdev);
1224                 bdput(pkt_bdev);
1225         }
1226
1227         if (!sb)
1228                 return 0;
1229
1230         if (!sb->s_op || !sb->s_op->relocate_blocks)
1231                 goto out;
1232
1233         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1234         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1235                 goto out;
1236
1237         new_sector = new_block * (CD_FRAMESIZE >> 9);
1238         pkt->sector = new_sector;
1239
1240         pkt->bio->bi_sector = new_sector;
1241         pkt->bio->bi_next = NULL;
1242         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
1243         pkt->bio->bi_idx = 0;
1244
1245         BUG_ON(pkt->bio->bi_rw != (1 << BIO_RW));
1246         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
1247         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
1248         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
1249         BUG_ON(pkt->bio->bi_private != pkt);
1250
1251         drop_super(sb);
1252         return 1;
1253
1254 out:
1255         drop_super(sb);
1256         return 0;
1257 #endif
1258 }
1259
1260 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1261 {
1262 #if PACKET_DEBUG > 1
1263         static const char *state_name[] = {
1264                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1265         };
1266         enum packet_data_state old_state = pkt->state;
1267         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1268                 state_name[old_state], state_name[state]);
1269 #endif
1270         pkt->state = state;
1271 }
1272
1273 /*
1274  * Scan the work queue to see if we can start a new packet.
1275  * returns non-zero if any work was done.
1276  */
1277 static int pkt_handle_queue(struct pktcdvd_device *pd)
1278 {
1279         struct packet_data *pkt, *p;
1280         struct bio *bio = NULL;
1281         sector_t zone = 0; /* Suppress gcc warning */
1282         struct pkt_rb_node *node, *first_node;
1283         struct rb_node *n;
1284         int wakeup;
1285
1286         VPRINTK("handle_queue\n");
1287
1288         atomic_set(&pd->scan_queue, 0);
1289
1290         if (list_empty(&pd->cdrw.pkt_free_list)) {
1291                 VPRINTK("handle_queue: no pkt\n");
1292                 return 0;
1293         }
1294
1295         /*
1296          * Try to find a zone we are not already working on.
1297          */
1298         spin_lock(&pd->lock);
1299         first_node = pkt_rbtree_find(pd, pd->current_sector);
1300         if (!first_node) {
1301                 n = rb_first(&pd->bio_queue);
1302                 if (n)
1303                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1304         }
1305         node = first_node;
1306         while (node) {
1307                 bio = node->bio;
1308                 zone = ZONE(bio->bi_sector, pd);
1309                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1310                         if (p->sector == zone) {
1311                                 bio = NULL;
1312                                 goto try_next_bio;
1313                         }
1314                 }
1315                 break;
1316 try_next_bio:
1317                 node = pkt_rbtree_next(node);
1318                 if (!node) {
1319                         n = rb_first(&pd->bio_queue);
1320                         if (n)
1321                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
1322                 }
1323                 if (node == first_node)
1324                         node = NULL;
1325         }
1326         spin_unlock(&pd->lock);
1327         if (!bio) {
1328                 VPRINTK("handle_queue: no bio\n");
1329                 return 0;
1330         }
1331
1332         pkt = pkt_get_packet_data(pd, zone);
1333
1334         pd->current_sector = zone + pd->settings.size;
1335         pkt->sector = zone;
1336         BUG_ON(pkt->frames != pd->settings.size >> 2);
1337         pkt->write_size = 0;
1338
1339         /*
1340          * Scan work queue for bios in the same zone and link them
1341          * to this packet.
1342          */
1343         spin_lock(&pd->lock);
1344         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1345         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1346                 bio = node->bio;
1347                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
1348                         (unsigned long long)ZONE(bio->bi_sector, pd));
1349                 if (ZONE(bio->bi_sector, pd) != zone)
1350                         break;
1351                 pkt_rbtree_erase(pd, node);
1352                 spin_lock(&pkt->lock);
1353                 pkt_add_list_last(bio, &pkt->orig_bios, &pkt->orig_bios_tail);
1354                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1355                 spin_unlock(&pkt->lock);
1356         }
1357         /* check write congestion marks, and if bio_queue_size is
1358            below, wake up any waiters */
1359         wakeup = (pd->write_congestion_on > 0
1360                         && pd->bio_queue_size <= pd->write_congestion_off);
1361         spin_unlock(&pd->lock);
1362         if (wakeup)
1363                 clear_bdi_congested(&pd->disk->queue->backing_dev_info, WRITE);
1364
1365         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1366         pkt_set_state(pkt, PACKET_WAITING_STATE);
1367         atomic_set(&pkt->run_sm, 1);
1368
1369         spin_lock(&pd->cdrw.active_list_lock);
1370         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1371         spin_unlock(&pd->cdrw.active_list_lock);
1372
1373         return 1;
1374 }
1375
1376 /*
1377  * Assemble a bio to write one packet and queue the bio for processing
1378  * by the underlying block device.
1379  */
1380 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1381 {
1382         struct bio *bio;
1383         int f;
1384         int frames_write;
1385         struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1386
1387         for (f = 0; f < pkt->frames; f++) {
1388                 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1389                 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1390         }
1391
1392         /*
1393          * Fill-in bvec with data from orig_bios.
1394          */
1395         frames_write = 0;
1396         spin_lock(&pkt->lock);
1397         for (bio = pkt->orig_bios; bio; bio = bio->bi_next) {
1398                 int segment = bio->bi_idx;
1399                 int src_offs = 0;
1400                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1401                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1402                 BUG_ON(first_frame < 0);
1403                 BUG_ON(first_frame + num_frames > pkt->frames);
1404                 for (f = first_frame; f < first_frame + num_frames; f++) {
1405                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1406
1407                         while (src_offs >= src_bvl->bv_len) {
1408                                 src_offs -= src_bvl->bv_len;
1409                                 segment++;
1410                                 BUG_ON(segment >= bio->bi_vcnt);
1411                                 src_bvl = bio_iovec_idx(bio, segment);
1412                         }
1413
1414                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1415                                 bvec[f].bv_page = src_bvl->bv_page;
1416                                 bvec[f].bv_offset = src_bvl->bv_offset + src_offs;
1417                         } else {
1418                                 pkt_copy_bio_data(bio, segment, src_offs,
1419                                                   bvec[f].bv_page, bvec[f].bv_offset);
1420                         }
1421                         src_offs += CD_FRAMESIZE;
1422                         frames_write++;
1423                 }
1424         }
1425         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1426         spin_unlock(&pkt->lock);
1427
1428         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1429                 frames_write, (unsigned long long)pkt->sector);
1430         BUG_ON(frames_write != pkt->write_size);
1431
1432         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1433                 pkt_make_local_copy(pkt, bvec);
1434                 pkt->cache_valid = 1;
1435         } else {
1436                 pkt->cache_valid = 0;
1437         }
1438
1439         /* Start the write request */
1440         bio_init(pkt->w_bio);
1441         pkt->w_bio->bi_max_vecs = PACKET_MAX_SIZE;
1442         pkt->w_bio->bi_sector = pkt->sector;
1443         pkt->w_bio->bi_bdev = pd->bdev;
1444         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1445         pkt->w_bio->bi_private = pkt;
1446         pkt->w_bio->bi_io_vec = bvec;
1447         for (f = 0; f < pkt->frames; f++)
1448                 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1449                         BUG();
1450         VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1451
1452         atomic_set(&pkt->io_wait, 1);
1453         pkt->w_bio->bi_rw = WRITE;
1454         pkt_queue_bio(pd, pkt->w_bio);
1455 }
1456
1457 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1458 {
1459         struct bio *bio, *next;
1460
1461         if (!uptodate)
1462                 pkt->cache_valid = 0;
1463
1464         /* Finish all bios corresponding to this packet */
1465         bio = pkt->orig_bios;
1466         while (bio) {
1467                 next = bio->bi_next;
1468                 bio->bi_next = NULL;
1469                 bio_endio(bio, uptodate ? 0 : -EIO);
1470                 bio = next;
1471         }
1472         pkt->orig_bios = pkt->orig_bios_tail = NULL;
1473 }
1474
1475 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1476 {
1477         int uptodate;
1478
1479         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1480
1481         for (;;) {
1482                 switch (pkt->state) {
1483                 case PACKET_WAITING_STATE:
1484                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1485                                 return;
1486
1487                         pkt->sleep_time = 0;
1488                         pkt_gather_data(pd, pkt);
1489                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1490                         break;
1491
1492                 case PACKET_READ_WAIT_STATE:
1493                         if (atomic_read(&pkt->io_wait) > 0)
1494                                 return;
1495
1496                         if (atomic_read(&pkt->io_errors) > 0) {
1497                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1498                         } else {
1499                                 pkt_start_write(pd, pkt);
1500                         }
1501                         break;
1502
1503                 case PACKET_WRITE_WAIT_STATE:
1504                         if (atomic_read(&pkt->io_wait) > 0)
1505                                 return;
1506
1507                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1508                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1509                         } else {
1510                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1511                         }
1512                         break;
1513
1514                 case PACKET_RECOVERY_STATE:
1515                         if (pkt_start_recovery(pkt)) {
1516                                 pkt_start_write(pd, pkt);
1517                         } else {
1518                                 VPRINTK("No recovery possible\n");
1519                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1520                         }
1521                         break;
1522
1523                 case PACKET_FINISHED_STATE:
1524                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1525                         pkt_finish_packet(pkt, uptodate);
1526                         return;
1527
1528                 default:
1529                         BUG();
1530                         break;
1531                 }
1532         }
1533 }
1534
1535 static void pkt_handle_packets(struct pktcdvd_device *pd)
1536 {
1537         struct packet_data *pkt, *next;
1538
1539         VPRINTK("pkt_handle_packets\n");
1540
1541         /*
1542          * Run state machine for active packets
1543          */
1544         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1545                 if (atomic_read(&pkt->run_sm) > 0) {
1546                         atomic_set(&pkt->run_sm, 0);
1547                         pkt_run_state_machine(pd, pkt);
1548                 }
1549         }
1550
1551         /*
1552          * Move no longer active packets to the free list
1553          */
1554         spin_lock(&pd->cdrw.active_list_lock);
1555         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1556                 if (pkt->state == PACKET_FINISHED_STATE) {
1557                         list_del(&pkt->list);
1558                         pkt_put_packet_data(pd, pkt);
1559                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1560                         atomic_set(&pd->scan_queue, 1);
1561                 }
1562         }
1563         spin_unlock(&pd->cdrw.active_list_lock);
1564 }
1565
1566 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1567 {
1568         struct packet_data *pkt;
1569         int i;
1570
1571         for (i = 0; i < PACKET_NUM_STATES; i++)
1572                 states[i] = 0;
1573
1574         spin_lock(&pd->cdrw.active_list_lock);
1575         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1576                 states[pkt->state]++;
1577         }
1578         spin_unlock(&pd->cdrw.active_list_lock);
1579 }
1580
1581 /*
1582  * kcdrwd is woken up when writes have been queued for one of our
1583  * registered devices
1584  */
1585 static int kcdrwd(void *foobar)
1586 {
1587         struct pktcdvd_device *pd = foobar;
1588         struct packet_data *pkt;
1589         long min_sleep_time, residue;
1590
1591         set_user_nice(current, -20);
1592         set_freezable();
1593
1594         for (;;) {
1595                 DECLARE_WAITQUEUE(wait, current);
1596
1597                 /*
1598                  * Wait until there is something to do
1599                  */
1600                 add_wait_queue(&pd->wqueue, &wait);
1601                 for (;;) {
1602                         set_current_state(TASK_INTERRUPTIBLE);
1603
1604                         /* Check if we need to run pkt_handle_queue */
1605                         if (atomic_read(&pd->scan_queue) > 0)
1606                                 goto work_to_do;
1607
1608                         /* Check if we need to run the state machine for some packet */
1609                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1610                                 if (atomic_read(&pkt->run_sm) > 0)
1611                                         goto work_to_do;
1612                         }
1613
1614                         /* Check if we need to process the iosched queues */
1615                         if (atomic_read(&pd->iosched.attention) != 0)
1616                                 goto work_to_do;
1617
1618                         /* Otherwise, go to sleep */
1619                         if (PACKET_DEBUG > 1) {
1620                                 int states[PACKET_NUM_STATES];
1621                                 pkt_count_states(pd, states);
1622                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1623                                         states[0], states[1], states[2], states[3],
1624                                         states[4], states[5]);
1625                         }
1626
1627                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1628                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1629                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1630                                         min_sleep_time = pkt->sleep_time;
1631                         }
1632
1633                         generic_unplug_device(bdev_get_queue(pd->bdev));
1634
1635                         VPRINTK("kcdrwd: sleeping\n");
1636                         residue = schedule_timeout(min_sleep_time);
1637                         VPRINTK("kcdrwd: wake up\n");
1638
1639                         /* make swsusp happy with our thread */
1640                         try_to_freeze();
1641
1642                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1643                                 if (!pkt->sleep_time)
1644                                         continue;
1645                                 pkt->sleep_time -= min_sleep_time - residue;
1646                                 if (pkt->sleep_time <= 0) {
1647                                         pkt->sleep_time = 0;
1648                                         atomic_inc(&pkt->run_sm);
1649                                 }
1650                         }
1651
1652                         if (kthread_should_stop())
1653                                 break;
1654                 }
1655 work_to_do:
1656                 set_current_state(TASK_RUNNING);
1657                 remove_wait_queue(&pd->wqueue, &wait);
1658
1659                 if (kthread_should_stop())
1660                         break;
1661
1662                 /*
1663                  * if pkt_handle_queue returns true, we can queue
1664                  * another request.
1665                  */
1666                 while (pkt_handle_queue(pd))
1667                         ;
1668
1669                 /*
1670                  * Handle packet state machine
1671                  */
1672                 pkt_handle_packets(pd);
1673
1674                 /*
1675                  * Handle iosched queues
1676                  */
1677                 pkt_iosched_process_queue(pd);
1678         }
1679
1680         return 0;
1681 }
1682
1683 static void pkt_print_settings(struct pktcdvd_device *pd)
1684 {
1685         printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1686         printk("%u blocks, ", pd->settings.size >> 2);
1687         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1688 }
1689
1690 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1691 {
1692         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1693
1694         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1695         cgc->cmd[2] = page_code | (page_control << 6);
1696         cgc->cmd[7] = cgc->buflen >> 8;
1697         cgc->cmd[8] = cgc->buflen & 0xff;
1698         cgc->data_direction = CGC_DATA_READ;
1699         return pkt_generic_packet(pd, cgc);
1700 }
1701
1702 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1703 {
1704         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1705         memset(cgc->buffer, 0, 2);
1706         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1707         cgc->cmd[1] = 0x10;             /* PF */
1708         cgc->cmd[7] = cgc->buflen >> 8;
1709         cgc->cmd[8] = cgc->buflen & 0xff;
1710         cgc->data_direction = CGC_DATA_WRITE;
1711         return pkt_generic_packet(pd, cgc);
1712 }
1713
1714 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1715 {
1716         struct packet_command cgc;
1717         int ret;
1718
1719         /* set up command and get the disc info */
1720         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1721         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1722         cgc.cmd[8] = cgc.buflen = 2;
1723         cgc.quiet = 1;
1724
1725         if ((ret = pkt_generic_packet(pd, &cgc)))
1726                 return ret;
1727
1728         /* not all drives have the same disc_info length, so requeue
1729          * packet with the length the drive tells us it can supply
1730          */
1731         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1732                      sizeof(di->disc_information_length);
1733
1734         if (cgc.buflen > sizeof(disc_information))
1735                 cgc.buflen = sizeof(disc_information);
1736
1737         cgc.cmd[8] = cgc.buflen;
1738         return pkt_generic_packet(pd, &cgc);
1739 }
1740
1741 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1742 {
1743         struct packet_command cgc;
1744         int ret;
1745
1746         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1747         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1748         cgc.cmd[1] = type & 3;
1749         cgc.cmd[4] = (track & 0xff00) >> 8;
1750         cgc.cmd[5] = track & 0xff;
1751         cgc.cmd[8] = 8;
1752         cgc.quiet = 1;
1753
1754         if ((ret = pkt_generic_packet(pd, &cgc)))
1755                 return ret;
1756
1757         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1758                      sizeof(ti->track_information_length);
1759
1760         if (cgc.buflen > sizeof(track_information))
1761                 cgc.buflen = sizeof(track_information);
1762
1763         cgc.cmd[8] = cgc.buflen;
1764         return pkt_generic_packet(pd, &cgc);
1765 }
1766
1767 static int pkt_get_last_written(struct pktcdvd_device *pd, long *last_written)
1768 {
1769         disc_information di;
1770         track_information ti;
1771         __u32 last_track;
1772         int ret = -1;
1773
1774         if ((ret = pkt_get_disc_info(pd, &di)))
1775                 return ret;
1776
1777         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1778         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1779                 return ret;
1780
1781         /* if this track is blank, try the previous. */
1782         if (ti.blank) {
1783                 last_track--;
1784                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1785                         return ret;
1786         }
1787
1788         /* if last recorded field is valid, return it. */
1789         if (ti.lra_v) {
1790                 *last_written = be32_to_cpu(ti.last_rec_address);
1791         } else {
1792                 /* make it up instead */
1793                 *last_written = be32_to_cpu(ti.track_start) +
1794                                 be32_to_cpu(ti.track_size);
1795                 if (ti.free_blocks)
1796                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1797         }
1798         return 0;
1799 }
1800
1801 /*
1802  * write mode select package based on pd->settings
1803  */
1804 static int pkt_set_write_settings(struct pktcdvd_device *pd)
1805 {
1806         struct packet_command cgc;
1807         struct request_sense sense;
1808         write_param_page *wp;
1809         char buffer[128];
1810         int ret, size;
1811
1812         /* doesn't apply to DVD+RW or DVD-RAM */
1813         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1814                 return 0;
1815
1816         memset(buffer, 0, sizeof(buffer));
1817         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1818         cgc.sense = &sense;
1819         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1820                 pkt_dump_sense(&cgc);
1821                 return ret;
1822         }
1823
1824         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1825         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1826         if (size > sizeof(buffer))
1827                 size = sizeof(buffer);
1828
1829         /*
1830          * now get it all
1831          */
1832         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1833         cgc.sense = &sense;
1834         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1835                 pkt_dump_sense(&cgc);
1836                 return ret;
1837         }
1838
1839         /*
1840          * write page is offset header + block descriptor length
1841          */
1842         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1843
1844         wp->fp = pd->settings.fp;
1845         wp->track_mode = pd->settings.track_mode;
1846         wp->write_type = pd->settings.write_type;
1847         wp->data_block_type = pd->settings.block_mode;
1848
1849         wp->multi_session = 0;
1850
1851 #ifdef PACKET_USE_LS
1852         wp->link_size = 7;
1853         wp->ls_v = 1;
1854 #endif
1855
1856         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1857                 wp->session_format = 0;
1858                 wp->subhdr2 = 0x20;
1859         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1860                 wp->session_format = 0x20;
1861                 wp->subhdr2 = 8;
1862 #if 0
1863                 wp->mcn[0] = 0x80;
1864                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1865 #endif
1866         } else {
1867                 /*
1868                  * paranoia
1869                  */
1870                 printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1871                 return 1;
1872         }
1873         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1874
1875         cgc.buflen = cgc.cmd[8] = size;
1876         if ((ret = pkt_mode_select(pd, &cgc))) {
1877                 pkt_dump_sense(&cgc);
1878                 return ret;
1879         }
1880
1881         pkt_print_settings(pd);
1882         return 0;
1883 }
1884
1885 /*
1886  * 1 -- we can write to this track, 0 -- we can't
1887  */
1888 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1889 {
1890         switch (pd->mmc3_profile) {
1891                 case 0x1a: /* DVD+RW */
1892                 case 0x12: /* DVD-RAM */
1893                         /* The track is always writable on DVD+RW/DVD-RAM */
1894                         return 1;
1895                 default:
1896                         break;
1897         }
1898
1899         if (!ti->packet || !ti->fp)
1900                 return 0;
1901
1902         /*
1903          * "good" settings as per Mt Fuji.
1904          */
1905         if (ti->rt == 0 && ti->blank == 0)
1906                 return 1;
1907
1908         if (ti->rt == 0 && ti->blank == 1)
1909                 return 1;
1910
1911         if (ti->rt == 1 && ti->blank == 0)
1912                 return 1;
1913
1914         printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1915         return 0;
1916 }
1917
1918 /*
1919  * 1 -- we can write to this disc, 0 -- we can't
1920  */
1921 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1922 {
1923         switch (pd->mmc3_profile) {
1924                 case 0x0a: /* CD-RW */
1925                 case 0xffff: /* MMC3 not supported */
1926                         break;
1927                 case 0x1a: /* DVD+RW */
1928                 case 0x13: /* DVD-RW */
1929                 case 0x12: /* DVD-RAM */
1930                         return 1;
1931                 default:
1932                         VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1933                         return 0;
1934         }
1935
1936         /*
1937          * for disc type 0xff we should probably reserve a new track.
1938          * but i'm not sure, should we leave this to user apps? probably.
1939          */
1940         if (di->disc_type == 0xff) {
1941                 printk(DRIVER_NAME": Unknown disc. No track?\n");
1942                 return 0;
1943         }
1944
1945         if (di->disc_type != 0x20 && di->disc_type != 0) {
1946                 printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1947                 return 0;
1948         }
1949
1950         if (di->erasable == 0) {
1951                 printk(DRIVER_NAME": Disc not erasable\n");
1952                 return 0;
1953         }
1954
1955         if (di->border_status == PACKET_SESSION_RESERVED) {
1956                 printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1957                 return 0;
1958         }
1959
1960         return 1;
1961 }
1962
1963 static int pkt_probe_settings(struct pktcdvd_device *pd)
1964 {
1965         struct packet_command cgc;
1966         unsigned char buf[12];
1967         disc_information di;
1968         track_information ti;
1969         int ret, track;
1970
1971         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1972         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1973         cgc.cmd[8] = 8;
1974         ret = pkt_generic_packet(pd, &cgc);
1975         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1976
1977         memset(&di, 0, sizeof(disc_information));
1978         memset(&ti, 0, sizeof(track_information));
1979
1980         if ((ret = pkt_get_disc_info(pd, &di))) {
1981                 printk("failed get_disc\n");
1982                 return ret;
1983         }
1984
1985         if (!pkt_writable_disc(pd, &di))
1986                 return -EROFS;
1987
1988         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1989
1990         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1991         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1992                 printk(DRIVER_NAME": failed get_track\n");
1993                 return ret;
1994         }
1995
1996         if (!pkt_writable_track(pd, &ti)) {
1997                 printk(DRIVER_NAME": can't write to this track\n");
1998                 return -EROFS;
1999         }
2000
2001         /*
2002          * we keep packet size in 512 byte units, makes it easier to
2003          * deal with request calculations.
2004          */
2005         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
2006         if (pd->settings.size == 0) {
2007                 printk(DRIVER_NAME": detected zero packet size!\n");
2008                 return -ENXIO;
2009         }
2010         if (pd->settings.size > PACKET_MAX_SECTORS) {
2011                 printk(DRIVER_NAME": packet size is too big\n");
2012                 return -EROFS;
2013         }
2014         pd->settings.fp = ti.fp;
2015         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
2016
2017         if (ti.nwa_v) {
2018                 pd->nwa = be32_to_cpu(ti.next_writable);
2019                 set_bit(PACKET_NWA_VALID, &pd->flags);
2020         }
2021
2022         /*
2023          * in theory we could use lra on -RW media as well and just zero
2024          * blocks that haven't been written yet, but in practice that
2025          * is just a no-go. we'll use that for -R, naturally.
2026          */
2027         if (ti.lra_v) {
2028                 pd->lra = be32_to_cpu(ti.last_rec_address);
2029                 set_bit(PACKET_LRA_VALID, &pd->flags);
2030         } else {
2031                 pd->lra = 0xffffffff;
2032                 set_bit(PACKET_LRA_VALID, &pd->flags);
2033         }
2034
2035         /*
2036          * fine for now
2037          */
2038         pd->settings.link_loss = 7;
2039         pd->settings.write_type = 0;    /* packet */
2040         pd->settings.track_mode = ti.track_mode;
2041
2042         /*
2043          * mode1 or mode2 disc
2044          */
2045         switch (ti.data_mode) {
2046                 case PACKET_MODE1:
2047                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
2048                         break;
2049                 case PACKET_MODE2:
2050                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
2051                         break;
2052                 default:
2053                         printk(DRIVER_NAME": unknown data mode\n");
2054                         return -EROFS;
2055         }
2056         return 0;
2057 }
2058
2059 /*
2060  * enable/disable write caching on drive
2061  */
2062 static int pkt_write_caching(struct pktcdvd_device *pd, int set)
2063 {
2064         struct packet_command cgc;
2065         struct request_sense sense;
2066         unsigned char buf[64];
2067         int ret;
2068
2069         memset(buf, 0, sizeof(buf));
2070         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
2071         cgc.sense = &sense;
2072         cgc.buflen = pd->mode_offset + 12;
2073
2074         /*
2075          * caching mode page might not be there, so quiet this command
2076          */
2077         cgc.quiet = 1;
2078
2079         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
2080                 return ret;
2081
2082         buf[pd->mode_offset + 10] |= (!!set << 2);
2083
2084         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
2085         ret = pkt_mode_select(pd, &cgc);
2086         if (ret) {
2087                 printk(DRIVER_NAME": write caching control failed\n");
2088                 pkt_dump_sense(&cgc);
2089         } else if (!ret && set)
2090                 printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
2091         return ret;
2092 }
2093
2094 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
2095 {
2096         struct packet_command cgc;
2097
2098         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2099         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
2100         cgc.cmd[4] = lockflag ? 1 : 0;
2101         return pkt_generic_packet(pd, &cgc);
2102 }
2103
2104 /*
2105  * Returns drive maximum write speed
2106  */
2107 static int pkt_get_max_speed(struct pktcdvd_device *pd, unsigned *write_speed)
2108 {
2109         struct packet_command cgc;
2110         struct request_sense sense;
2111         unsigned char buf[256+18];
2112         unsigned char *cap_buf;
2113         int ret, offset;
2114
2115         memset(buf, 0, sizeof(buf));
2116         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
2117         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2118         cgc.sense = &sense;
2119
2120         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2121         if (ret) {
2122                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2123                              sizeof(struct mode_page_header);
2124                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2125                 if (ret) {
2126                         pkt_dump_sense(&cgc);
2127                         return ret;
2128                 }
2129         }
2130
2131         offset = 20;                        /* Obsoleted field, used by older drives */
2132         if (cap_buf[1] >= 28)
2133                 offset = 28;                /* Current write speed selected */
2134         if (cap_buf[1] >= 30) {
2135                 /* If the drive reports at least one "Logical Unit Write
2136                  * Speed Performance Descriptor Block", use the information
2137                  * in the first block. (contains the highest speed)
2138                  */
2139                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2140                 if (num_spdb > 0)
2141                         offset = 34;
2142         }
2143
2144         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2145         return 0;
2146 }
2147
2148 /* These tables from cdrecord - I don't have orange book */
2149 /* standard speed CD-RW (1-4x) */
2150 static char clv_to_speed[16] = {
2151         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2152            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2153 };
2154 /* high speed CD-RW (-10x) */
2155 static char hs_clv_to_speed[16] = {
2156         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2157            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2158 };
2159 /* ultra high speed CD-RW */
2160 static char us_clv_to_speed[16] = {
2161         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2162            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2163 };
2164
2165 /*
2166  * reads the maximum media speed from ATIP
2167  */
2168 static int pkt_media_speed(struct pktcdvd_device *pd, unsigned *speed)
2169 {
2170         struct packet_command cgc;
2171         struct request_sense sense;
2172         unsigned char buf[64];
2173         unsigned int size, st, sp;
2174         int ret;
2175
2176         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2177         cgc.sense = &sense;
2178         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2179         cgc.cmd[1] = 2;
2180         cgc.cmd[2] = 4; /* READ ATIP */
2181         cgc.cmd[8] = 2;
2182         ret = pkt_generic_packet(pd, &cgc);
2183         if (ret) {
2184                 pkt_dump_sense(&cgc);
2185                 return ret;
2186         }
2187         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2188         if (size > sizeof(buf))
2189                 size = sizeof(buf);
2190
2191         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2192         cgc.sense = &sense;
2193         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2194         cgc.cmd[1] = 2;
2195         cgc.cmd[2] = 4;
2196         cgc.cmd[8] = size;
2197         ret = pkt_generic_packet(pd, &cgc);
2198         if (ret) {
2199                 pkt_dump_sense(&cgc);
2200                 return ret;
2201         }
2202
2203         if (!buf[6] & 0x40) {
2204                 printk(DRIVER_NAME": Disc type is not CD-RW\n");
2205                 return 1;
2206         }
2207         if (!buf[6] & 0x4) {
2208                 printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2209                 return 1;
2210         }
2211
2212         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2213
2214         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2215
2216         /* Info from cdrecord */
2217         switch (st) {
2218                 case 0: /* standard speed */
2219                         *speed = clv_to_speed[sp];
2220                         break;
2221                 case 1: /* high speed */
2222                         *speed = hs_clv_to_speed[sp];
2223                         break;
2224                 case 2: /* ultra high speed */
2225                         *speed = us_clv_to_speed[sp];
2226                         break;
2227                 default:
2228                         printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2229                         return 1;
2230         }
2231         if (*speed) {
2232                 printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2233                 return 0;
2234         } else {
2235                 printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2236                 return 1;
2237         }
2238 }
2239
2240 static int pkt_perform_opc(struct pktcdvd_device *pd)
2241 {
2242         struct packet_command cgc;
2243         struct request_sense sense;
2244         int ret;
2245
2246         VPRINTK(DRIVER_NAME": Performing OPC\n");
2247
2248         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2249         cgc.sense = &sense;
2250         cgc.timeout = 60*HZ;
2251         cgc.cmd[0] = GPCMD_SEND_OPC;
2252         cgc.cmd[1] = 1;
2253         if ((ret = pkt_generic_packet(pd, &cgc)))
2254                 pkt_dump_sense(&cgc);
2255         return ret;
2256 }
2257
2258 static int pkt_open_write(struct pktcdvd_device *pd)
2259 {
2260         int ret;
2261         unsigned int write_speed, media_write_speed, read_speed;
2262
2263         if ((ret = pkt_probe_settings(pd))) {
2264                 VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2265                 return ret;
2266         }
2267
2268         if ((ret = pkt_set_write_settings(pd))) {
2269                 DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2270                 return -EIO;
2271         }
2272
2273         pkt_write_caching(pd, USE_WCACHING);
2274
2275         if ((ret = pkt_get_max_speed(pd, &write_speed)))
2276                 write_speed = 16 * 177;
2277         switch (pd->mmc3_profile) {
2278                 case 0x13: /* DVD-RW */
2279                 case 0x1a: /* DVD+RW */
2280                 case 0x12: /* DVD-RAM */
2281                         DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2282                         break;
2283                 default:
2284                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
2285                                 media_write_speed = 16;
2286                         write_speed = min(write_speed, media_write_speed * 177);
2287                         DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2288                         break;
2289         }
2290         read_speed = write_speed;
2291
2292         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2293                 DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2294                 return -EIO;
2295         }
2296         pd->write_speed = write_speed;
2297         pd->read_speed = read_speed;
2298
2299         if ((ret = pkt_perform_opc(pd))) {
2300                 DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2301         }
2302
2303         return 0;
2304 }
2305
2306 /*
2307  * called at open time.
2308  */
2309 static int pkt_open_dev(struct pktcdvd_device *pd, int write)
2310 {
2311         int ret;
2312         long lba;
2313         struct request_queue *q;
2314
2315         /*
2316          * We need to re-open the cdrom device without O_NONBLOCK to be able
2317          * to read/write from/to it. It is already opened in O_NONBLOCK mode
2318          * so bdget() can't fail.
2319          */
2320         bdget(pd->bdev->bd_dev);
2321         if ((ret = blkdev_get(pd->bdev, FMODE_READ, O_RDONLY)))
2322                 goto out;
2323
2324         if ((ret = bd_claim(pd->bdev, pd)))
2325                 goto out_putdev;
2326
2327         if ((ret = pkt_get_last_written(pd, &lba))) {
2328                 printk(DRIVER_NAME": pkt_get_last_written failed\n");
2329                 goto out_unclaim;
2330         }
2331
2332         set_capacity(pd->disk, lba << 2);
2333         set_capacity(pd->bdev->bd_disk, lba << 2);
2334         bd_set_size(pd->bdev, (loff_t)lba << 11);
2335
2336         q = bdev_get_queue(pd->bdev);
2337         if (write) {
2338                 if ((ret = pkt_open_write(pd)))
2339                         goto out_unclaim;
2340                 /*
2341                  * Some CDRW drives can not handle writes larger than one packet,
2342                  * even if the size is a multiple of the packet size.
2343                  */
2344                 spin_lock_irq(q->queue_lock);
2345                 blk_queue_max_sectors(q, pd->settings.size);
2346                 spin_unlock_irq(q->queue_lock);
2347                 set_bit(PACKET_WRITABLE, &pd->flags);
2348         } else {
2349                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2350                 clear_bit(PACKET_WRITABLE, &pd->flags);
2351         }
2352
2353         if ((ret = pkt_set_segment_merging(pd, q)))
2354                 goto out_unclaim;
2355
2356         if (write) {
2357                 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2358                         printk(DRIVER_NAME": not enough memory for buffers\n");
2359                         ret = -ENOMEM;
2360                         goto out_unclaim;
2361                 }
2362                 printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2363         }
2364
2365         return 0;
2366
2367 out_unclaim:
2368         bd_release(pd->bdev);
2369 out_putdev:
2370         blkdev_put(pd->bdev);
2371 out:
2372         return ret;
2373 }
2374
2375 /*
2376  * called when the device is closed. makes sure that the device flushes
2377  * the internal cache before we close.
2378  */
2379 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2380 {
2381         if (flush && pkt_flush_cache(pd))
2382                 DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2383
2384         pkt_lock_door(pd, 0);
2385
2386         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2387         bd_release(pd->bdev);
2388         blkdev_put(pd->bdev);
2389
2390         pkt_shrink_pktlist(pd);
2391 }
2392
2393 static struct pktcdvd_device *pkt_find_dev_from_minor(int dev_minor)
2394 {
2395         if (dev_minor >= MAX_WRITERS)
2396                 return NULL;
2397         return pkt_devs[dev_minor];
2398 }
2399
2400 static int pkt_open(struct inode *inode, struct file *file)
2401 {
2402         struct pktcdvd_device *pd = NULL;
2403         int ret;
2404
2405         VPRINTK(DRIVER_NAME": entering open\n");
2406
2407         mutex_lock(&ctl_mutex);
2408         pd = pkt_find_dev_from_minor(iminor(inode));
2409         if (!pd) {
2410                 ret = -ENODEV;
2411                 goto out;
2412         }
2413         BUG_ON(pd->refcnt < 0);
2414
2415         pd->refcnt++;
2416         if (pd->refcnt > 1) {
2417                 if ((file->f_mode & FMODE_WRITE) &&
2418                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2419                         ret = -EBUSY;
2420                         goto out_dec;
2421                 }
2422         } else {
2423                 ret = pkt_open_dev(pd, file->f_mode & FMODE_WRITE);
2424                 if (ret)
2425                         goto out_dec;
2426                 /*
2427                  * needed here as well, since ext2 (among others) may change
2428                  * the blocksize at mount time
2429                  */
2430                 set_blocksize(inode->i_bdev, CD_FRAMESIZE);
2431         }
2432
2433         mutex_unlock(&ctl_mutex);
2434         return 0;
2435
2436 out_dec:
2437         pd->refcnt--;
2438 out:
2439         VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2440         mutex_unlock(&ctl_mutex);
2441         return ret;
2442 }
2443
2444 static int pkt_close(struct inode *inode, struct file *file)
2445 {
2446         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2447         int ret = 0;
2448
2449         mutex_lock(&ctl_mutex);
2450         pd->refcnt--;
2451         BUG_ON(pd->refcnt < 0);
2452         if (pd->refcnt == 0) {
2453                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2454                 pkt_release_dev(pd, flush);
2455         }
2456         mutex_unlock(&ctl_mutex);
2457         return ret;
2458 }
2459
2460
2461 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2462 {
2463         struct packet_stacked_data *psd = bio->bi_private;
2464         struct pktcdvd_device *pd = psd->pd;
2465
2466         bio_put(bio);
2467         bio_endio(psd->bio, err);
2468         mempool_free(psd, psd_pool);
2469         pkt_bio_finished(pd);
2470 }
2471
2472 static int pkt_make_request(struct request_queue *q, struct bio *bio)
2473 {
2474         struct pktcdvd_device *pd;
2475         char b[BDEVNAME_SIZE];
2476         sector_t zone;
2477         struct packet_data *pkt;
2478         int was_empty, blocked_bio;
2479         struct pkt_rb_node *node;
2480
2481         pd = q->queuedata;
2482         if (!pd) {
2483                 printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2484                 goto end_io;
2485         }
2486
2487         /*
2488          * Clone READ bios so we can have our own bi_end_io callback.
2489          */
2490         if (bio_data_dir(bio) == READ) {
2491                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2492                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2493
2494                 psd->pd = pd;
2495                 psd->bio = bio;
2496                 cloned_bio->bi_bdev = pd->bdev;
2497                 cloned_bio->bi_private = psd;
2498                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2499                 pd->stats.secs_r += bio->bi_size >> 9;
2500                 pkt_queue_bio(pd, cloned_bio);
2501                 return 0;
2502         }
2503
2504         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2505                 printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2506                         pd->name, (unsigned long long)bio->bi_sector);
2507                 goto end_io;
2508         }
2509
2510         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2511                 printk(DRIVER_NAME": wrong bio size\n");
2512                 goto end_io;
2513         }
2514
2515         blk_queue_bounce(q, &bio);
2516
2517         zone = ZONE(bio->bi_sector, pd);
2518         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2519                 (unsigned long long)bio->bi_sector,
2520                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2521
2522         /* Check if we have to split the bio */
2523         {
2524                 struct bio_pair *bp;
2525                 sector_t last_zone;
2526                 int first_sectors;
2527
2528                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2529                 if (last_zone != zone) {
2530                         BUG_ON(last_zone != zone + pd->settings.size);
2531                         first_sectors = last_zone - bio->bi_sector;
2532                         bp = bio_split(bio, bio_split_pool, first_sectors);
2533                         BUG_ON(!bp);
2534                         pkt_make_request(q, &bp->bio1);
2535                         pkt_make_request(q, &bp->bio2);
2536                         bio_pair_release(bp);
2537                         return 0;
2538                 }
2539         }
2540
2541         /*
2542          * If we find a matching packet in state WAITING or READ_WAIT, we can
2543          * just append this bio to that packet.
2544          */
2545         spin_lock(&pd->cdrw.active_list_lock);
2546         blocked_bio = 0;
2547         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2548                 if (pkt->sector == zone) {
2549                         spin_lock(&pkt->lock);
2550                         if ((pkt->state == PACKET_WAITING_STATE) ||
2551                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2552                                 pkt_add_list_last(bio, &pkt->orig_bios,
2553                                                   &pkt->orig_bios_tail);
2554                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2555                                 if ((pkt->write_size >= pkt->frames) &&
2556                                     (pkt->state == PACKET_WAITING_STATE)) {
2557                                         atomic_inc(&pkt->run_sm);
2558                                         wake_up(&pd->wqueue);
2559                                 }
2560                                 spin_unlock(&pkt->lock);
2561                                 spin_unlock(&pd->cdrw.active_list_lock);
2562                                 return 0;
2563                         } else {
2564                                 blocked_bio = 1;
2565                         }
2566                         spin_unlock(&pkt->lock);
2567                 }
2568         }
2569         spin_unlock(&pd->cdrw.active_list_lock);
2570
2571         /*
2572          * Test if there is enough room left in the bio work queue
2573          * (queue size >= congestion on mark).
2574          * If not, wait till the work queue size is below the congestion off mark.
2575          */
2576         spin_lock(&pd->lock);
2577         if (pd->write_congestion_on > 0
2578             && pd->bio_queue_size >= pd->write_congestion_on) {
2579                 set_bdi_congested(&q->backing_dev_info, WRITE);
2580                 do {
2581                         spin_unlock(&pd->lock);
2582                         congestion_wait(WRITE, HZ);
2583                         spin_lock(&pd->lock);
2584                 } while(pd->bio_queue_size > pd->write_congestion_off);
2585         }
2586         spin_unlock(&pd->lock);
2587
2588         /*
2589          * No matching packet found. Store the bio in the work queue.
2590          */
2591         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2592         node->bio = bio;
2593         spin_lock(&pd->lock);
2594         BUG_ON(pd->bio_queue_size < 0);
2595         was_empty = (pd->bio_queue_size == 0);
2596         pkt_rbtree_insert(pd, node);
2597         spin_unlock(&pd->lock);
2598
2599         /*
2600          * Wake up the worker thread.
2601          */
2602         atomic_set(&pd->scan_queue, 1);
2603         if (was_empty) {
2604                 /* This wake_up is required for correct operation */
2605                 wake_up(&pd->wqueue);
2606         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2607                 /*
2608                  * This wake up is not required for correct operation,
2609                  * but improves performance in some cases.
2610                  */
2611                 wake_up(&pd->wqueue);
2612         }
2613         return 0;
2614 end_io:
2615         bio_io_error(bio);
2616         return 0;
2617 }
2618
2619
2620
2621 static int pkt_merge_bvec(struct request_queue *q, struct bio *bio, struct bio_vec *bvec)
2622 {
2623         struct pktcdvd_device *pd = q->queuedata;
2624         sector_t zone = ZONE(bio->bi_sector, pd);
2625         int used = ((bio->bi_sector - zone) << 9) + bio->bi_size;
2626         int remaining = (pd->settings.size << 9) - used;
2627         int remaining2;
2628
2629         /*
2630          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2631          * boundary, pkt_make_request() will split the bio.
2632          */
2633         remaining2 = PAGE_SIZE - bio->bi_size;
2634         remaining = max(remaining, remaining2);
2635
2636         BUG_ON(remaining < 0);
2637         return remaining;
2638 }
2639
2640 static void pkt_init_queue(struct pktcdvd_device *pd)
2641 {
2642         struct request_queue *q = pd->disk->queue;
2643
2644         blk_queue_make_request(q, pkt_make_request);
2645         blk_queue_hardsect_size(q, CD_FRAMESIZE);
2646         blk_queue_max_sectors(q, PACKET_MAX_SECTORS);
2647         blk_queue_merge_bvec(q, pkt_merge_bvec);
2648         q->queuedata = pd;
2649 }
2650
2651 static int pkt_seq_show(struct seq_file *m, void *p)
2652 {
2653         struct pktcdvd_device *pd = m->private;
2654         char *msg;
2655         char bdev_buf[BDEVNAME_SIZE];
2656         int states[PACKET_NUM_STATES];
2657
2658         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2659                    bdevname(pd->bdev, bdev_buf));
2660
2661         seq_printf(m, "\nSettings:\n");
2662         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2663
2664         if (pd->settings.write_type == 0)
2665                 msg = "Packet";
2666         else
2667                 msg = "Unknown";
2668         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2669
2670         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2671         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2672
2673         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2674
2675         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2676                 msg = "Mode 1";
2677         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2678                 msg = "Mode 2";
2679         else
2680                 msg = "Unknown";
2681         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2682
2683         seq_printf(m, "\nStatistics:\n");
2684         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2685         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2686         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2687         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2688         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2689
2690         seq_printf(m, "\nMisc:\n");
2691         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2692         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2693         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2694         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2695         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2696         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2697
2698         seq_printf(m, "\nQueue state:\n");
2699         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2700         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2701         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2702
2703         pkt_count_states(pd, states);
2704         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2705                    states[0], states[1], states[2], states[3], states[4], states[5]);
2706
2707         seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2708                         pd->write_congestion_off,
2709                         pd->write_congestion_on);
2710         return 0;
2711 }
2712
2713 static int pkt_seq_open(struct inode *inode, struct file *file)
2714 {
2715         return single_open(file, pkt_seq_show, PDE(inode)->data);
2716 }
2717
2718 static const struct file_operations pkt_proc_fops = {
2719         .open   = pkt_seq_open,
2720         .read   = seq_read,
2721         .llseek = seq_lseek,
2722         .release = single_release
2723 };
2724
2725 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2726 {
2727         int i;
2728         int ret = 0;
2729         char b[BDEVNAME_SIZE];
2730         struct proc_dir_entry *proc;
2731         struct block_device *bdev;
2732
2733         if (pd->pkt_dev == dev) {
2734                 printk(DRIVER_NAME": Recursive setup not allowed\n");
2735                 return -EBUSY;
2736         }
2737         for (i = 0; i < MAX_WRITERS; i++) {
2738                 struct pktcdvd_device *pd2 = pkt_devs[i];
2739                 if (!pd2)
2740                         continue;
2741                 if (pd2->bdev->bd_dev == dev) {
2742                         printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
2743                         return -EBUSY;
2744                 }
2745                 if (pd2->pkt_dev == dev) {
2746                         printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2747                         return -EBUSY;
2748                 }
2749         }
2750
2751         bdev = bdget(dev);
2752         if (!bdev)
2753                 return -ENOMEM;
2754         ret = blkdev_get(bdev, FMODE_READ, O_RDONLY | O_NONBLOCK);
2755         if (ret)
2756                 return ret;
2757
2758         /* This is safe, since we have a reference from open(). */
2759         __module_get(THIS_MODULE);
2760
2761         pd->bdev = bdev;
2762         set_blocksize(bdev, CD_FRAMESIZE);
2763
2764         pkt_init_queue(pd);
2765
2766         atomic_set(&pd->cdrw.pending_bios, 0);
2767         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2768         if (IS_ERR(pd->cdrw.thread)) {
2769                 printk(DRIVER_NAME": can't start kernel thread\n");
2770                 ret = -ENOMEM;
2771                 goto out_mem;
2772         }
2773
2774         proc = create_proc_entry(pd->name, 0, pkt_proc);
2775         if (proc) {
2776                 proc->data = pd;
2777                 proc->proc_fops = &pkt_proc_fops;
2778         }
2779         DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2780         return 0;
2781
2782 out_mem:
2783         blkdev_put(bdev);
2784         /* This is safe: open() is still holding a reference. */
2785         module_put(THIS_MODULE);
2786         return ret;
2787 }
2788
2789 static int pkt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
2790 {
2791         struct pktcdvd_device *pd = inode->i_bdev->bd_disk->private_data;
2792
2793         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd, imajor(inode), iminor(inode));
2794
2795         switch (cmd) {
2796         /*
2797          * forward selected CDROM ioctls to CD-ROM, for UDF
2798          */
2799         case CDROMMULTISESSION:
2800         case CDROMREADTOCENTRY:
2801         case CDROM_LAST_WRITTEN:
2802         case CDROM_SEND_PACKET:
2803         case SCSI_IOCTL_SEND_COMMAND:
2804                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2805
2806         case CDROMEJECT:
2807                 /*
2808                  * The door gets locked when the device is opened, so we
2809                  * have to unlock it or else the eject command fails.
2810                  */
2811                 if (pd->refcnt == 1)
2812                         pkt_lock_door(pd, 0);
2813                 return blkdev_ioctl(pd->bdev->bd_inode, file, cmd, arg);
2814
2815         default:
2816                 VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2817                 return -ENOTTY;
2818         }
2819
2820         return 0;
2821 }
2822
2823 static int pkt_media_changed(struct gendisk *disk)
2824 {
2825         struct pktcdvd_device *pd = disk->private_data;
2826         struct gendisk *attached_disk;
2827
2828         if (!pd)
2829                 return 0;
2830         if (!pd->bdev)
2831                 return 0;
2832         attached_disk = pd->bdev->bd_disk;
2833         if (!attached_disk)
2834                 return 0;
2835         return attached_disk->fops->media_changed(attached_disk);
2836 }
2837
2838 static struct block_device_operations pktcdvd_ops = {
2839         .owner =                THIS_MODULE,
2840         .open =                 pkt_open,
2841         .release =              pkt_close,
2842         .ioctl =                pkt_ioctl,
2843         .media_changed =        pkt_media_changed,
2844 };
2845
2846 /*
2847  * Set up mapping from pktcdvd device to CD-ROM device.
2848  */
2849 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2850 {
2851         int idx;
2852         int ret = -ENOMEM;
2853         struct pktcdvd_device *pd;
2854         struct gendisk *disk;
2855
2856         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2857
2858         for (idx = 0; idx < MAX_WRITERS; idx++)
2859                 if (!pkt_devs[idx])
2860                         break;
2861         if (idx == MAX_WRITERS) {
2862                 printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2863                 ret = -EBUSY;
2864                 goto out_mutex;
2865         }
2866
2867         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2868         if (!pd)
2869                 goto out_mutex;
2870
2871         pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2872                                                   sizeof(struct pkt_rb_node));
2873         if (!pd->rb_pool)
2874                 goto out_mem;
2875
2876         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2877         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2878         spin_lock_init(&pd->cdrw.active_list_lock);
2879
2880         spin_lock_init(&pd->lock);
2881         spin_lock_init(&pd->iosched.lock);
2882         sprintf(pd->name, DRIVER_NAME"%d", idx);
2883         init_waitqueue_head(&pd->wqueue);
2884         pd->bio_queue = RB_ROOT;
2885
2886         pd->write_congestion_on  = write_congestion_on;
2887         pd->write_congestion_off = write_congestion_off;
2888
2889         disk = alloc_disk(1);
2890         if (!disk)
2891                 goto out_mem;
2892         pd->disk = disk;
2893         disk->major = pktdev_major;
2894         disk->first_minor = idx;
2895         disk->fops = &pktcdvd_ops;
2896         disk->flags = GENHD_FL_REMOVABLE;
2897         strcpy(disk->disk_name, pd->name);
2898         disk->private_data = pd;
2899         disk->queue = blk_alloc_queue(GFP_KERNEL);
2900         if (!disk->queue)
2901                 goto out_mem2;
2902
2903         pd->pkt_dev = MKDEV(disk->major, disk->first_minor);
2904         ret = pkt_new_dev(pd, dev);
2905         if (ret)
2906                 goto out_new_dev;
2907
2908         add_disk(disk);
2909
2910         pkt_sysfs_dev_new(pd);
2911         pkt_debugfs_dev_new(pd);
2912
2913         pkt_devs[idx] = pd;
2914         if (pkt_dev)
2915                 *pkt_dev = pd->pkt_dev;
2916
2917         mutex_unlock(&ctl_mutex);
2918         return 0;
2919
2920 out_new_dev:
2921         blk_cleanup_queue(disk->queue);
2922 out_mem2:
2923         put_disk(disk);
2924 out_mem:
2925         if (pd->rb_pool)
2926                 mempool_destroy(pd->rb_pool);
2927         kfree(pd);
2928 out_mutex:
2929         mutex_unlock(&ctl_mutex);
2930         printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2931         return ret;
2932 }
2933
2934 /*
2935  * Tear down mapping from pktcdvd device to CD-ROM device.
2936  */
2937 static int pkt_remove_dev(dev_t pkt_dev)
2938 {
2939         struct pktcdvd_device *pd;
2940         int idx;
2941         int ret = 0;
2942
2943         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2944
2945         for (idx = 0; idx < MAX_WRITERS; idx++) {
2946                 pd = pkt_devs[idx];
2947                 if (pd && (pd->pkt_dev == pkt_dev))
2948                         break;
2949         }
2950         if (idx == MAX_WRITERS) {
2951                 DPRINTK(DRIVER_NAME": dev not setup\n");
2952                 ret = -ENXIO;
2953                 goto out;
2954         }
2955
2956         if (pd->refcnt > 0) {
2957                 ret = -EBUSY;
2958                 goto out;
2959         }
2960         if (!IS_ERR(pd->cdrw.thread))
2961                 kthread_stop(pd->cdrw.thread);
2962
2963         pkt_devs[idx] = NULL;
2964
2965         pkt_debugfs_dev_remove(pd);
2966         pkt_sysfs_dev_remove(pd);
2967
2968         blkdev_put(pd->bdev);
2969
2970         remove_proc_entry(pd->name, pkt_proc);
2971         DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2972
2973         del_gendisk(pd->disk);
2974         blk_cleanup_queue(pd->disk->queue);
2975         put_disk(pd->disk);
2976
2977         mempool_destroy(pd->rb_pool);
2978         kfree(pd);
2979
2980         /* This is safe: open() is still holding a reference. */
2981         module_put(THIS_MODULE);
2982
2983 out:
2984         mutex_unlock(&ctl_mutex);
2985         return ret;
2986 }
2987
2988 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2989 {
2990         struct pktcdvd_device *pd;
2991
2992         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2993
2994         pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2995         if (pd) {
2996                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2997                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2998         } else {
2999                 ctrl_cmd->dev = 0;
3000                 ctrl_cmd->pkt_dev = 0;
3001         }
3002         ctrl_cmd->num_devices = MAX_WRITERS;
3003
3004         mutex_unlock(&ctl_mutex);
3005 }
3006
3007 static int pkt_ctl_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
3008 {
3009         void __user *argp = (void __user *)arg;
3010         struct pkt_ctrl_command ctrl_cmd;
3011         int ret = 0;
3012         dev_t pkt_dev = 0;
3013
3014         if (cmd != PACKET_CTRL_CMD)
3015                 return -ENOTTY;
3016
3017         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
3018                 return -EFAULT;
3019
3020         switch (ctrl_cmd.command) {
3021         case PKT_CTRL_CMD_SETUP:
3022                 if (!capable(CAP_SYS_ADMIN))
3023                         return -EPERM;
3024                 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
3025                 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
3026                 break;
3027         case PKT_CTRL_CMD_TEARDOWN:
3028                 if (!capable(CAP_SYS_ADMIN))
3029                         return -EPERM;
3030                 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
3031                 break;
3032         case PKT_CTRL_CMD_STATUS:
3033                 pkt_get_status(&ctrl_cmd);
3034                 break;
3035         default:
3036                 return -ENOTTY;
3037         }
3038
3039         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
3040                 return -EFAULT;
3041         return ret;
3042 }
3043
3044
3045 static const struct file_operations pkt_ctl_fops = {
3046         .ioctl   = pkt_ctl_ioctl,
3047         .owner   = THIS_MODULE,
3048 };
3049
3050 static struct miscdevice pkt_misc = {
3051         .minor          = MISC_DYNAMIC_MINOR,
3052         .name           = DRIVER_NAME,
3053         .fops           = &pkt_ctl_fops
3054 };
3055
3056 static int __init pkt_init(void)
3057 {
3058         int ret;
3059
3060         mutex_init(&ctl_mutex);
3061
3062         psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
3063                                         sizeof(struct packet_stacked_data));
3064         if (!psd_pool)
3065                 return -ENOMEM;
3066
3067         ret = register_blkdev(pktdev_major, DRIVER_NAME);
3068         if (ret < 0) {
3069                 printk(DRIVER_NAME": Unable to register block device\n");
3070                 goto out2;
3071         }
3072         if (!pktdev_major)
3073                 pktdev_major = ret;
3074
3075         ret = pkt_sysfs_init();
3076         if (ret)
3077                 goto out;
3078
3079         pkt_debugfs_init();
3080
3081         ret = misc_register(&pkt_misc);
3082         if (ret) {
3083                 printk(DRIVER_NAME": Unable to register misc device\n");
3084                 goto out_misc;
3085         }
3086
3087         pkt_proc = proc_mkdir(DRIVER_NAME, proc_root_driver);
3088
3089         return 0;
3090
3091 out_misc:
3092         pkt_debugfs_cleanup();
3093         pkt_sysfs_cleanup();
3094 out:
3095         unregister_blkdev(pktdev_major, DRIVER_NAME);
3096 out2:
3097         mempool_destroy(psd_pool);
3098         return ret;
3099 }
3100
3101 static void __exit pkt_exit(void)
3102 {
3103         remove_proc_entry(DRIVER_NAME, proc_root_driver);
3104         misc_deregister(&pkt_misc);
3105
3106         pkt_debugfs_cleanup();
3107         pkt_sysfs_cleanup();
3108
3109         unregister_blkdev(pktdev_major, DRIVER_NAME);
3110         mempool_destroy(psd_pool);
3111 }
3112
3113 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3114 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3115 MODULE_LICENSE("GPL");
3116
3117 module_init(pkt_init);
3118 module_exit(pkt_exit);