drivers/block/pktcdvd.c

   1 /*
   2  * Copyright (C) 2000 Jens Axboe <axboe@suse.de>
   3  * Copyright (C) 2001-2004 Peter Osterlund <petero2@telia.com>
   4  * Copyright (C) 2006 Thomas Maier <balagi@justmail.de>
   5  *
   6  * May be copied or modified under the terms of the GNU General Public
   7  * License.  See linux/COPYING for more information.
   8  *
   9  * Packet writing layer for ATAPI and SCSI CD-RW, DVD+RW, DVD-RW and
  10  * DVD-RAM devices.
  11  *
  12  * Theory of operation:
  13  *
  14  * At the lowest level, there is the standard driver for the CD/DVD device,
  15  * typically ide-cd.c or sr.c. This driver can handle read and write requests,
  16  * but it doesn't know anything about the special restrictions that apply to
  17  * packet writing. One restriction is that write requests must be aligned to
  18  * packet boundaries on the physical media, and the size of a write request
  19  * must be equal to the packet size. Another restriction is that a
  20  * GPCMD_FLUSH_CACHE command has to be issued to the drive before a read
  21  * command, if the previous command was a write.
  22  *
  23  * The purpose of the packet writing driver is to hide these restrictions from
  24  * higher layers, such as file systems, and present a block device that can be
  25  * randomly read and written using 2kB-sized blocks.
  26  *
  27  * The lowest layer in the packet writing driver is the packet I/O scheduler.
  28  * Its data is defined by the struct packet_iosched and includes two bio
  29  * queues with pending read and write requests. These queues are processed
  30  * by the pkt_iosched_process_queue() function. The write requests in this
  31  * queue are already properly aligned and sized. This layer is responsible for
  32  * issuing the flush cache commands and scheduling the I/O in a good order.
  33  *
  34  * The next layer transforms unaligned write requests to aligned writes. This
  35  * transformation requires reading missing pieces of data from the underlying
  36  * block device, assembling the pieces to full packets and queuing them to the
  37  * packet I/O scheduler.
  38  *
  39  * At the top layer there is a custom make_request_fn function that forwards
  40  * read requests directly to the iosched queue and puts write requests in the
  41  * unaligned write queue. A kernel thread performs the necessary read
  42  * gathering to convert the unaligned writes to aligned writes and then feeds
  43  * them to the packet I/O scheduler.
  44  *
  45  *************************************************************************/
  46
  47 #include <linux/pktcdvd.h>
  48 #include <linux/module.h>
  49 #include <linux/types.h>
  50 #include <linux/kernel.h>
  51 #include <linux/compat.h>
  52 #include <linux/kthread.h>
  53 #include <linux/errno.h>
  54 #include <linux/spinlock.h>
  55 #include <linux/file.h>
  56 #include <linux/proc_fs.h>
  57 #include <linux/seq_file.h>
  58 #include <linux/miscdevice.h>
  59 #include <linux/freezer.h>
  60 #include <linux/mutex.h>
  61 #include <linux/slab.h>
  62 #include <scsi/scsi_cmnd.h>
  63 #include <scsi/scsi_ioctl.h>
  64 #include <scsi/scsi.h>
  65 #include <linux/debugfs.h>
  66 #include <linux/device.h>
  67
  68 #include <asm/uaccess.h>
  69
  70 #define DRIVER_NAME     "pktcdvd"
  71
  72 #if PACKET_DEBUG
  73 #define DPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  74 #else
  75 #define DPRINTK(fmt, args...)
  76 #endif
  77
  78 #if PACKET_DEBUG > 1
  79 #define VPRINTK(fmt, args...) printk(KERN_NOTICE fmt, ##args)
  80 #else
  81 #define VPRINTK(fmt, args...)
  82 #endif
  83
  84 #define MAX_SPEED 0xffff
  85
  86 #define ZONE(sector, pd) (((sector) + (pd)->offset) & ~((pd)->settings.size - 1))
  87
  88 static DEFINE_MUTEX(pktcdvd_mutex);
  89 static struct pktcdvd_device *pkt_devs[MAX_WRITERS];
  90 static struct proc_dir_entry *pkt_proc;
  91 static int pktdev_major;
  92 static int write_congestion_on  = PKT_WRITE_CONGESTION_ON;
  93 static int write_congestion_off = PKT_WRITE_CONGESTION_OFF;
  94 static struct mutex ctl_mutex;  /* Serialize open/close/setup/teardown */
  95 static mempool_t *psd_pool;
  96
  97 static struct class     *class_pktcdvd = NULL;    /* /sys/class/pktcdvd */
  98 static struct dentry    *pkt_debugfs_root = NULL; /* /sys/kernel/debug/pktcdvd */
  99
 100 /* forward declaration */
 101 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev);
 102 static int pkt_remove_dev(dev_t pkt_dev);
 103 static int pkt_seq_show(struct seq_file *m, void *p);
 104
 105
 106
 107 /*
 108  * create and register a pktcdvd kernel object.
 109  */
 110 static struct pktcdvd_kobj* pkt_kobj_create(struct pktcdvd_device *pd,
 111                                         const char* name,
 112                                         struct kobject* parent,
 113                                         struct kobj_type* ktype)
 114 {
 115         struct pktcdvd_kobj *p;
 116         int error;
 117
 118         p = kzalloc(sizeof(*p), GFP_KERNEL);
 119         if (!p)
 120                 return NULL;
 121         p->pd = pd;
 122         error = kobject_init_and_add(&p->kobj, ktype, parent, "%s", name);
 123         if (error) {
 124                 kobject_put(&p->kobj);
 125                 return NULL;
 126         }
 127         kobject_uevent(&p->kobj, KOBJ_ADD);
 128         return p;
 129 }
 130 /*
 131  * remove a pktcdvd kernel object.
 132  */
 133 static void pkt_kobj_remove(struct pktcdvd_kobj *p)
 134 {
 135         if (p)
 136                 kobject_put(&p->kobj);
 137 }
 138 /*
 139  * default release function for pktcdvd kernel objects.
 140  */
 141 static void pkt_kobj_release(struct kobject *kobj)
 142 {
 143         kfree(to_pktcdvdkobj(kobj));
 144 }
 145
 146
 147 /**********************************************************
 148  *
 149  * sysfs interface for pktcdvd
 150  * by (C) 2006  Thomas Maier <balagi@justmail.de>
 151  *
 152  **********************************************************/
 153
 154 #define DEF_ATTR(_obj,_name,_mode) \
 155         static struct attribute _obj = { .name = _name, .mode = _mode }
 156
 157 /**********************************************************
 158   /sys/class/pktcdvd/pktcdvd[0-7]/
 159                      stat/reset
 160                      stat/packets_started
 161                      stat/packets_finished
 162                      stat/kb_written
 163                      stat/kb_read
 164                      stat/kb_read_gather
 165                      write_queue/size
 166                      write_queue/congestion_off
 167                      write_queue/congestion_on
 168  **********************************************************/
 169
 170 DEF_ATTR(kobj_pkt_attr_st1, "reset", 0200);
 171 DEF_ATTR(kobj_pkt_attr_st2, "packets_started", 0444);
 172 DEF_ATTR(kobj_pkt_attr_st3, "packets_finished", 0444);
 173 DEF_ATTR(kobj_pkt_attr_st4, "kb_written", 0444);
 174 DEF_ATTR(kobj_pkt_attr_st5, "kb_read", 0444);
 175 DEF_ATTR(kobj_pkt_attr_st6, "kb_read_gather", 0444);
 176
 177 static struct attribute *kobj_pkt_attrs_stat[] = {
 178         &kobj_pkt_attr_st1,
 179         &kobj_pkt_attr_st2,
 180         &kobj_pkt_attr_st3,
 181         &kobj_pkt_attr_st4,
 182         &kobj_pkt_attr_st5,
 183         &kobj_pkt_attr_st6,
 184         NULL
 185 };
 186
 187 DEF_ATTR(kobj_pkt_attr_wq1, "size", 0444);
 188 DEF_ATTR(kobj_pkt_attr_wq2, "congestion_off", 0644);
 189 DEF_ATTR(kobj_pkt_attr_wq3, "congestion_on",  0644);
 190
 191 static struct attribute *kobj_pkt_attrs_wqueue[] = {
 192         &kobj_pkt_attr_wq1,
 193         &kobj_pkt_attr_wq2,
 194         &kobj_pkt_attr_wq3,
 195         NULL
 196 };
 197
 198 static ssize_t kobj_pkt_show(struct kobject *kobj,
 199                         struct attribute *attr, char *data)
 200 {
 201         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 202         int n = 0;
 203         int v;
 204         if (strcmp(attr->name, "packets_started") == 0) {
 205                 n = sprintf(data, "%lu\n", pd->stats.pkt_started);
 206
 207         } else if (strcmp(attr->name, "packets_finished") == 0) {
 208                 n = sprintf(data, "%lu\n", pd->stats.pkt_ended);
 209
 210         } else if (strcmp(attr->name, "kb_written") == 0) {
 211                 n = sprintf(data, "%lu\n", pd->stats.secs_w >> 1);
 212
 213         } else if (strcmp(attr->name, "kb_read") == 0) {
 214                 n = sprintf(data, "%lu\n", pd->stats.secs_r >> 1);
 215
 216         } else if (strcmp(attr->name, "kb_read_gather") == 0) {
 217                 n = sprintf(data, "%lu\n", pd->stats.secs_rg >> 1);
 218
 219         } else if (strcmp(attr->name, "size") == 0) {
 220                 spin_lock(&pd->lock);
 221                 v = pd->bio_queue_size;
 222                 spin_unlock(&pd->lock);
 223                 n = sprintf(data, "%d\n", v);
 224
 225         } else if (strcmp(attr->name, "congestion_off") == 0) {
 226                 spin_lock(&pd->lock);
 227                 v = pd->write_congestion_off;
 228                 spin_unlock(&pd->lock);
 229                 n = sprintf(data, "%d\n", v);
 230
 231         } else if (strcmp(attr->name, "congestion_on") == 0) {
 232                 spin_lock(&pd->lock);
 233                 v = pd->write_congestion_on;
 234                 spin_unlock(&pd->lock);
 235                 n = sprintf(data, "%d\n", v);
 236         }
 237         return n;
 238 }
 239
 240 static void init_write_congestion_marks(int* lo, int* hi)
 241 {
 242         if (*hi > 0) {
 243                 *hi = max(*hi, 500);
 244                 *hi = min(*hi, 1000000);
 245                 if (*lo <= 0)
 246                         *lo = *hi - 100;
 247                 else {
 248                         *lo = min(*lo, *hi - 100);
 249                         *lo = max(*lo, 100);
 250                 }
 251         } else {
 252                 *hi = -1;
 253                 *lo = -1;
 254         }
 255 }
 256
 257 static ssize_t kobj_pkt_store(struct kobject *kobj,
 258                         struct attribute *attr,
 259                         const char *data, size_t len)
 260 {
 261         struct pktcdvd_device *pd = to_pktcdvdkobj(kobj)->pd;
 262         int val;
 263
 264         if (strcmp(attr->name, "reset") == 0 && len > 0) {
 265                 pd->stats.pkt_started = 0;
 266                 pd->stats.pkt_ended = 0;
 267                 pd->stats.secs_w = 0;
 268                 pd->stats.secs_rg = 0;
 269                 pd->stats.secs_r = 0;
 270
 271         } else if (strcmp(attr->name, "congestion_off") == 0
 272                    && sscanf(data, "%d", &val) == 1) {
 273                 spin_lock(&pd->lock);
 274                 pd->write_congestion_off = val;
 275                 init_write_congestion_marks(&pd->write_congestion_off,
 276                                         &pd->write_congestion_on);
 277                 spin_unlock(&pd->lock);
 278
 279         } else if (strcmp(attr->name, "congestion_on") == 0
 280                    && sscanf(data, "%d", &val) == 1) {
 281                 spin_lock(&pd->lock);
 282                 pd->write_congestion_on = val;
 283                 init_write_congestion_marks(&pd->write_congestion_off,
 284                                         &pd->write_congestion_on);
 285                 spin_unlock(&pd->lock);
 286         }
 287         return len;
 288 }
 289
 290 static const struct sysfs_ops kobj_pkt_ops = {
 291         .show = kobj_pkt_show,
 292         .store = kobj_pkt_store
 293 };
 294 static struct kobj_type kobj_pkt_type_stat = {
 295         .release = pkt_kobj_release,
 296         .sysfs_ops = &kobj_pkt_ops,
 297         .default_attrs = kobj_pkt_attrs_stat
 298 };
 299 static struct kobj_type kobj_pkt_type_wqueue = {
 300         .release = pkt_kobj_release,
 301         .sysfs_ops = &kobj_pkt_ops,
 302         .default_attrs = kobj_pkt_attrs_wqueue
 303 };
 304
 305 static void pkt_sysfs_dev_new(struct pktcdvd_device *pd)
 306 {
 307         if (class_pktcdvd) {
 308                 pd->dev = device_create(class_pktcdvd, NULL, MKDEV(0, 0), NULL,
 309                                         "%s", pd->name);
 310                 if (IS_ERR(pd->dev))
 311                         pd->dev = NULL;
 312         }
 313         if (pd->dev) {
 314                 pd->kobj_stat = pkt_kobj_create(pd, "stat",
 315                                         &pd->dev->kobj,
 316                                         &kobj_pkt_type_stat);
 317                 pd->kobj_wqueue = pkt_kobj_create(pd, "write_queue",
 318                                         &pd->dev->kobj,
 319                                         &kobj_pkt_type_wqueue);
 320         }
 321 }
 322
 323 static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 324 {
 325         pkt_kobj_remove(pd->kobj_stat);
 326         pkt_kobj_remove(pd->kobj_wqueue);
 327         if (class_pktcdvd)
 328                 device_unregister(pd->dev);
 329 }
 330
 331
 332 /********************************************************************
 333   /sys/class/pktcdvd/
 334                      add            map block device
 335                      remove         unmap packet dev
 336                      device_map     show mappings
 337  *******************************************************************/
 338
 339 static void class_pktcdvd_release(struct class *cls)
 340 {
 341         kfree(cls);
 342 }
 343 static ssize_t class_pktcdvd_show_map(struct class *c,
 344                                         struct class_attribute *attr,
 345                                         char *data)
 346 {
 347         int n = 0;
 348         int idx;
 349         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
 350         for (idx = 0; idx < MAX_WRITERS; idx++) {
 351                 struct pktcdvd_device *pd = pkt_devs[idx];
 352                 if (!pd)
 353                         continue;
 354                 n += sprintf(data+n, "%s %u:%u %u:%u\n",
 355                         pd->name,
 356                         MAJOR(pd->pkt_dev), MINOR(pd->pkt_dev),
 357                         MAJOR(pd->bdev->bd_dev),
 358                         MINOR(pd->bdev->bd_dev));
 359         }
 360         mutex_unlock(&ctl_mutex);
 361         return n;
 362 }
 363
 364 static ssize_t class_pktcdvd_store_add(struct class *c,
 365                                         struct class_attribute *attr,
 366                                         const char *buf,
 367                                         size_t count)
 368 {
 369         unsigned int major, minor;
 370
 371         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 372                 /* pkt_setup_dev() expects caller to hold reference to self */
 373                 if (!try_module_get(THIS_MODULE))
 374                         return -ENODEV;
 375
 376                 pkt_setup_dev(MKDEV(major, minor), NULL);
 377
 378                 module_put(THIS_MODULE);
 379
 380                 return count;
 381         }
 382
 383         return -EINVAL;
 384 }
 385
 386 static ssize_t class_pktcdvd_store_remove(struct class *c,
 387                                           struct class_attribute *attr,
 388                                           const char *buf,
 389                                         size_t count)
 390 {
 391         unsigned int major, minor;
 392         if (sscanf(buf, "%u:%u", &major, &minor) == 2) {
 393                 pkt_remove_dev(MKDEV(major, minor));
 394                 return count;
 395         }
 396         return -EINVAL;
 397 }
 398
 399 static struct class_attribute class_pktcdvd_attrs[] = {
 400  __ATTR(add,            0200, NULL, class_pktcdvd_store_add),
 401  __ATTR(remove,         0200, NULL, class_pktcdvd_store_remove),
 402  __ATTR(device_map,     0444, class_pktcdvd_show_map, NULL),
 403  __ATTR_NULL
 404 };
 405
 406
 407 static int pkt_sysfs_init(void)
 408 {
 409         int ret = 0;
 410
 411         /*
 412          * create control files in sysfs
 413          * /sys/class/pktcdvd/...
 414          */
 415         class_pktcdvd = kzalloc(sizeof(*class_pktcdvd), GFP_KERNEL);
 416         if (!class_pktcdvd)
 417                 return -ENOMEM;
 418         class_pktcdvd->name = DRIVER_NAME;
 419         class_pktcdvd->owner = THIS_MODULE;
 420         class_pktcdvd->class_release = class_pktcdvd_release;
 421         class_pktcdvd->class_attrs = class_pktcdvd_attrs;
 422         ret = class_register(class_pktcdvd);
 423         if (ret) {
 424                 kfree(class_pktcdvd);
 425                 class_pktcdvd = NULL;
 426                 printk(DRIVER_NAME": failed to create class pktcdvd\n");
 427                 return ret;
 428         }
 429         return 0;
 430 }
 431
 432 static void pkt_sysfs_cleanup(void)
 433 {
 434         if (class_pktcdvd)
 435                 class_destroy(class_pktcdvd);
 436         class_pktcdvd = NULL;
 437 }
 438
 439 /********************************************************************
 440   entries in debugfs
 441
 442   /sys/kernel/debug/pktcdvd[0-7]/
 443                         info
 444
 445  *******************************************************************/
 446
 447 static int pkt_debugfs_seq_show(struct seq_file *m, void *p)
 448 {
 449         return pkt_seq_show(m, p);
 450 }
 451
 452 static int pkt_debugfs_fops_open(struct inode *inode, struct file *file)
 453 {
 454         return single_open(file, pkt_debugfs_seq_show, inode->i_private);
 455 }
 456
 457 static const struct file_operations debug_fops = {
 458         .open           = pkt_debugfs_fops_open,
 459         .read           = seq_read,
 460         .llseek         = seq_lseek,
 461         .release        = single_release,
 462         .owner          = THIS_MODULE,
 463 };
 464
 465 static void pkt_debugfs_dev_new(struct pktcdvd_device *pd)
 466 {
 467         if (!pkt_debugfs_root)
 468                 return;
 469         pd->dfs_f_info = NULL;
 470         pd->dfs_d_root = debugfs_create_dir(pd->name, pkt_debugfs_root);
 471         if (IS_ERR(pd->dfs_d_root)) {
 472                 pd->dfs_d_root = NULL;
 473                 return;
 474         }
 475         pd->dfs_f_info = debugfs_create_file("info", S_IRUGO,
 476                                 pd->dfs_d_root, pd, &debug_fops);
 477         if (IS_ERR(pd->dfs_f_info)) {
 478                 pd->dfs_f_info = NULL;
 479                 return;
 480         }
 481 }
 482
 483 static void pkt_debugfs_dev_remove(struct pktcdvd_device *pd)
 484 {
 485         if (!pkt_debugfs_root)
 486                 return;
 487         if (pd->dfs_f_info)
 488                 debugfs_remove(pd->dfs_f_info);
 489         pd->dfs_f_info = NULL;
 490         if (pd->dfs_d_root)
 491                 debugfs_remove(pd->dfs_d_root);
 492         pd->dfs_d_root = NULL;
 493 }
 494
 495 static void pkt_debugfs_init(void)
 496 {
 497         pkt_debugfs_root = debugfs_create_dir(DRIVER_NAME, NULL);
 498         if (IS_ERR(pkt_debugfs_root)) {
 499                 pkt_debugfs_root = NULL;
 500                 return;
 501         }
 502 }
 503
 504 static void pkt_debugfs_cleanup(void)
 505 {
 506         if (!pkt_debugfs_root)
 507                 return;
 508         debugfs_remove(pkt_debugfs_root);
 509         pkt_debugfs_root = NULL;
 510 }
 511
 512 /* ----------------------------------------------------------*/
 513
 514
 515 static void pkt_bio_finished(struct pktcdvd_device *pd)
 516 {
 517         BUG_ON(atomic_read(&pd->cdrw.pending_bios) <= 0);
 518         if (atomic_dec_and_test(&pd->cdrw.pending_bios)) {
 519                 VPRINTK(DRIVER_NAME": queue empty\n");
 520                 atomic_set(&pd->iosched.attention, 1);
 521                 wake_up(&pd->wqueue);
 522         }
 523 }
 524
 525 /*
 526  * Allocate a packet_data struct
 527  */
 528 static struct packet_data *pkt_alloc_packet_data(int frames)
 529 {
 530         int i;
 531         struct packet_data *pkt;
 532
 533         pkt = kzalloc(sizeof(struct packet_data), GFP_KERNEL);
 534         if (!pkt)
 535                 goto no_pkt;
 536
 537         pkt->frames = frames;
 538         pkt->w_bio = bio_kmalloc(GFP_KERNEL, frames);
 539         if (!pkt->w_bio)
 540                 goto no_bio;
 541
 542         for (i = 0; i < frames / FRAMES_PER_PAGE; i++) {
 543                 pkt->pages[i] = alloc_page(GFP_KERNEL|__GFP_ZERO);
 544                 if (!pkt->pages[i])
 545                         goto no_page;
 546         }
 547
 548         spin_lock_init(&pkt->lock);
 549         bio_list_init(&pkt->orig_bios);
 550
 551         for (i = 0; i < frames; i++) {
 552                 struct bio *bio = bio_kmalloc(GFP_KERNEL, 1);
 553                 if (!bio)
 554                         goto no_rd_bio;
 555
 556                 pkt->r_bios[i] = bio;
 557         }
 558
 559         return pkt;
 560
 561 no_rd_bio:
 562         for (i = 0; i < frames; i++) {
 563                 struct bio *bio = pkt->r_bios[i];
 564                 if (bio)
 565                         bio_put(bio);
 566         }
 567
 568 no_page:
 569         for (i = 0; i < frames / FRAMES_PER_PAGE; i++)
 570                 if (pkt->pages[i])
 571                         __free_page(pkt->pages[i]);
 572         bio_put(pkt->w_bio);
 573 no_bio:
 574         kfree(pkt);
 575 no_pkt:
 576         return NULL;
 577 }
 578
 579 /*
 580  * Free a packet_data struct
 581  */
 582 static void pkt_free_packet_data(struct packet_data *pkt)
 583 {
 584         int i;
 585
 586         for (i = 0; i < pkt->frames; i++) {
 587                 struct bio *bio = pkt->r_bios[i];
 588                 if (bio)
 589                         bio_put(bio);
 590         }
 591         for (i = 0; i < pkt->frames / FRAMES_PER_PAGE; i++)
 592                 __free_page(pkt->pages[i]);
 593         bio_put(pkt->w_bio);
 594         kfree(pkt);
 595 }
 596
 597 static void pkt_shrink_pktlist(struct pktcdvd_device *pd)
 598 {
 599         struct packet_data *pkt, *next;
 600
 601         BUG_ON(!list_empty(&pd->cdrw.pkt_active_list));
 602
 603         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_free_list, list) {
 604                 pkt_free_packet_data(pkt);
 605         }
 606         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
 607 }
 608
 609 static int pkt_grow_pktlist(struct pktcdvd_device *pd, int nr_packets)
 610 {
 611         struct packet_data *pkt;
 612
 613         BUG_ON(!list_empty(&pd->cdrw.pkt_free_list));
 614
 615         while (nr_packets > 0) {
 616                 pkt = pkt_alloc_packet_data(pd->settings.size >> 2);
 617                 if (!pkt) {
 618                         pkt_shrink_pktlist(pd);
 619                         return 0;
 620                 }
 621                 pkt->id = nr_packets;
 622                 pkt->pd = pd;
 623                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
 624                 nr_packets--;
 625         }
 626         return 1;
 627 }
 628
 629 static inline struct pkt_rb_node *pkt_rbtree_next(struct pkt_rb_node *node)
 630 {
 631         struct rb_node *n = rb_next(&node->rb_node);
 632         if (!n)
 633                 return NULL;
 634         return rb_entry(n, struct pkt_rb_node, rb_node);
 635 }
 636
 637 static void pkt_rbtree_erase(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 638 {
 639         rb_erase(&node->rb_node, &pd->bio_queue);
 640         mempool_free(node, pd->rb_pool);
 641         pd->bio_queue_size--;
 642         BUG_ON(pd->bio_queue_size < 0);
 643 }
 644
 645 /*
 646  * Find the first node in the pd->bio_queue rb tree with a starting sector >= s.
 647  */
 648 static struct pkt_rb_node *pkt_rbtree_find(struct pktcdvd_device *pd, sector_t s)
 649 {
 650         struct rb_node *n = pd->bio_queue.rb_node;
 651         struct rb_node *next;
 652         struct pkt_rb_node *tmp;
 653
 654         if (!n) {
 655                 BUG_ON(pd->bio_queue_size > 0);
 656                 return NULL;
 657         }
 658
 659         for (;;) {
 660                 tmp = rb_entry(n, struct pkt_rb_node, rb_node);
 661                 if (s <= tmp->bio->bi_sector)
 662                         next = n->rb_left;
 663                 else
 664                         next = n->rb_right;
 665                 if (!next)
 666                         break;
 667                 n = next;
 668         }
 669
 670         if (s > tmp->bio->bi_sector) {
 671                 tmp = pkt_rbtree_next(tmp);
 672                 if (!tmp)
 673                         return NULL;
 674         }
 675         BUG_ON(s > tmp->bio->bi_sector);
 676         return tmp;
 677 }
 678
 679 /*
 680  * Insert a node into the pd->bio_queue rb tree.
 681  */
 682 static void pkt_rbtree_insert(struct pktcdvd_device *pd, struct pkt_rb_node *node)
 683 {
 684         struct rb_node **p = &pd->bio_queue.rb_node;
 685         struct rb_node *parent = NULL;
 686         sector_t s = node->bio->bi_sector;
 687         struct pkt_rb_node *tmp;
 688
 689         while (*p) {
 690                 parent = *p;
 691                 tmp = rb_entry(parent, struct pkt_rb_node, rb_node);
 692                 if (s < tmp->bio->bi_sector)
 693                         p = &(*p)->rb_left;
 694                 else
 695                         p = &(*p)->rb_right;
 696         }
 697         rb_link_node(&node->rb_node, parent, p);
 698         rb_insert_color(&node->rb_node, &pd->bio_queue);
 699         pd->bio_queue_size++;
 700 }
 701
 702 /*
 703  * Send a packet_command to the underlying block device and
 704  * wait for completion.
 705  */
 706 static int pkt_generic_packet(struct pktcdvd_device *pd, struct packet_command *cgc)
 707 {
 708         struct request_queue *q = bdev_get_queue(pd->bdev);
 709         struct request *rq;
 710         int ret = 0;
 711
 712         rq = blk_get_request(q, (cgc->data_direction == CGC_DATA_WRITE) ?
 713                              WRITE : READ, __GFP_WAIT);
 714
 715         if (cgc->buflen) {
 716                 if (blk_rq_map_kern(q, rq, cgc->buffer, cgc->buflen, __GFP_WAIT))
 717                         goto out;
 718         }
 719
 720         rq->cmd_len = COMMAND_SIZE(cgc->cmd[0]);
 721         memcpy(rq->cmd, cgc->cmd, CDROM_PACKET_SIZE);
 722
 723         rq->timeout = 60*HZ;
 724         rq->cmd_type = REQ_TYPE_BLOCK_PC;
 725         if (cgc->quiet)
 726                 rq->cmd_flags |= REQ_QUIET;
 727
 728         blk_execute_rq(rq->q, pd->bdev->bd_disk, rq, 0);
 729         if (rq->errors)
 730                 ret = -EIO;
 731 out:
 732         blk_put_request(rq);
 733         return ret;
 734 }
 735
 736 /*
 737  * A generic sense dump / resolve mechanism should be implemented across
 738  * all ATAPI + SCSI devices.
 739  */
 740 static void pkt_dump_sense(struct packet_command *cgc)
 741 {
 742         static char *info[9] = { "No sense", "Recovered error", "Not ready",
 743                                  "Medium error", "Hardware error", "Illegal request",
 744                                  "Unit attention", "Data protect", "Blank check" };
 745         int i;
 746         struct request_sense *sense = cgc->sense;
 747
 748         printk(DRIVER_NAME":");
 749         for (i = 0; i < CDROM_PACKET_SIZE; i++)
 750                 printk(" %02x", cgc->cmd[i]);
 751         printk(" - ");
 752
 753         if (sense == NULL) {
 754                 printk("no sense\n");
 755                 return;
 756         }
 757
 758         printk("sense %02x.%02x.%02x", sense->sense_key, sense->asc, sense->ascq);
 759
 760         if (sense->sense_key > 8) {
 761                 printk(" (INVALID)\n");
 762                 return;
 763         }
 764
 765         printk(" (%s)\n", info[sense->sense_key]);
 766 }
 767
 768 /*
 769  * flush the drive cache to media
 770  */
 771 static int pkt_flush_cache(struct pktcdvd_device *pd)
 772 {
 773         struct packet_command cgc;
 774
 775         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 776         cgc.cmd[0] = GPCMD_FLUSH_CACHE;
 777         cgc.quiet = 1;
 778
 779         /*
 780          * the IMMED bit -- we default to not setting it, although that
 781          * would allow a much faster close, this is safer
 782          */
 783 #if 0
 784         cgc.cmd[1] = 1 << 1;
 785 #endif
 786         return pkt_generic_packet(pd, &cgc);
 787 }
 788
 789 /*
 790  * speed is given as the normal factor, e.g. 4 for 4x
 791  */
 792 static noinline_for_stack int pkt_set_speed(struct pktcdvd_device *pd,
 793                                 unsigned write_speed, unsigned read_speed)
 794 {
 795         struct packet_command cgc;
 796         struct request_sense sense;
 797         int ret;
 798
 799         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
 800         cgc.sense = &sense;
 801         cgc.cmd[0] = GPCMD_SET_SPEED;
 802         cgc.cmd[2] = (read_speed >> 8) & 0xff;
 803         cgc.cmd[3] = read_speed & 0xff;
 804         cgc.cmd[4] = (write_speed >> 8) & 0xff;
 805         cgc.cmd[5] = write_speed & 0xff;
 806
 807         if ((ret = pkt_generic_packet(pd, &cgc)))
 808                 pkt_dump_sense(&cgc);
 809
 810         return ret;
 811 }
 812
 813 /*
 814  * Queue a bio for processing by the low-level CD device. Must be called
 815  * from process context.
 816  */
 817 static void pkt_queue_bio(struct pktcdvd_device *pd, struct bio *bio)
 818 {
 819         spin_lock(&pd->iosched.lock);
 820         if (bio_data_dir(bio) == READ)
 821                 bio_list_add(&pd->iosched.read_queue, bio);
 822         else
 823                 bio_list_add(&pd->iosched.write_queue, bio);
 824         spin_unlock(&pd->iosched.lock);
 825
 826         atomic_set(&pd->iosched.attention, 1);
 827         wake_up(&pd->wqueue);
 828 }
 829
 830 /*
 831  * Process the queued read/write requests. This function handles special
 832  * requirements for CDRW drives:
 833  * - A cache flush command must be inserted before a read request if the
 834  *   previous request was a write.
 835  * - Switching between reading and writing is slow, so don't do it more often
 836  *   than necessary.
 837  * - Optimize for throughput at the expense of latency. This means that streaming
 838  *   writes will never be interrupted by a read, but if the drive has to seek
 839  *   before the next write, switch to reading instead if there are any pending
 840  *   read requests.
 841  * - Set the read speed according to current usage pattern. When only reading
 842  *   from the device, it's best to use the highest possible read speed, but
 843  *   when switching often between reading and writing, it's better to have the
 844  *   same read and write speeds.
 845  */
 846 static void pkt_iosched_process_queue(struct pktcdvd_device *pd)
 847 {
 848
 849         if (atomic_read(&pd->iosched.attention) == 0)
 850                 return;
 851         atomic_set(&pd->iosched.attention, 0);
 852
 853         for (;;) {
 854                 struct bio *bio;
 855                 int reads_queued, writes_queued;
 856
 857                 spin_lock(&pd->iosched.lock);
 858                 reads_queued = !bio_list_empty(&pd->iosched.read_queue);
 859                 writes_queued = !bio_list_empty(&pd->iosched.write_queue);
 860                 spin_unlock(&pd->iosched.lock);
 861
 862                 if (!reads_queued && !writes_queued)
 863                         break;
 864
 865                 if (pd->iosched.writing) {
 866                         int need_write_seek = 1;
 867                         spin_lock(&pd->iosched.lock);
 868                         bio = bio_list_peek(&pd->iosched.write_queue);
 869                         spin_unlock(&pd->iosched.lock);
 870                         if (bio && (bio->bi_sector == pd->iosched.last_write))
 871                                 need_write_seek = 0;
 872                         if (need_write_seek && reads_queued) {
 873                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 874                                         VPRINTK(DRIVER_NAME": write, waiting\n");
 875                                         break;
 876                                 }
 877                                 pkt_flush_cache(pd);
 878                                 pd->iosched.writing = 0;
 879                         }
 880                 } else {
 881                         if (!reads_queued && writes_queued) {
 882                                 if (atomic_read(&pd->cdrw.pending_bios) > 0) {
 883                                         VPRINTK(DRIVER_NAME": read, waiting\n");
 884                                         break;
 885                                 }
 886                                 pd->iosched.writing = 1;
 887                         }
 888                 }
 889
 890                 spin_lock(&pd->iosched.lock);
 891                 if (pd->iosched.writing)
 892                         bio = bio_list_pop(&pd->iosched.write_queue);
 893                 else
 894                         bio = bio_list_pop(&pd->iosched.read_queue);
 895                 spin_unlock(&pd->iosched.lock);
 896
 897                 if (!bio)
 898                         continue;
 899
 900                 if (bio_data_dir(bio) == READ)
 901                         pd->iosched.successive_reads += bio->bi_size >> 10;
 902                 else {
 903                         pd->iosched.successive_reads = 0;
 904                         pd->iosched.last_write = bio->bi_sector + bio_sectors(bio);
 905                 }
 906                 if (pd->iosched.successive_reads >= HI_SPEED_SWITCH) {
 907                         if (pd->read_speed == pd->write_speed) {
 908                                 pd->read_speed = MAX_SPEED;
 909                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 910                         }
 911                 } else {
 912                         if (pd->read_speed != pd->write_speed) {
 913                                 pd->read_speed = pd->write_speed;
 914                                 pkt_set_speed(pd, pd->write_speed, pd->read_speed);
 915                         }
 916                 }
 917
 918                 atomic_inc(&pd->cdrw.pending_bios);
 919                 generic_make_request(bio);
 920         }
 921 }
 922
 923 /*
 924  * Special care is needed if the underlying block device has a small
 925  * max_phys_segments value.
 926  */
 927 static int pkt_set_segment_merging(struct pktcdvd_device *pd, struct request_queue *q)
 928 {
 929         if ((pd->settings.size << 9) / CD_FRAMESIZE
 930             <= queue_max_segments(q)) {
 931                 /*
 932                  * The cdrom device can handle one segment/frame
 933                  */
 934                 clear_bit(PACKET_MERGE_SEGS, &pd->flags);
 935                 return 0;
 936         } else if ((pd->settings.size << 9) / PAGE_SIZE
 937                    <= queue_max_segments(q)) {
 938                 /*
 939                  * We can handle this case at the expense of some extra memory
 940                  * copies during write operations
 941                  */
 942                 set_bit(PACKET_MERGE_SEGS, &pd->flags);
 943                 return 0;
 944         } else {
 945                 printk(DRIVER_NAME": cdrom max_phys_segments too small\n");
 946                 return -EIO;
 947         }
 948 }
 949
 950 /*
 951  * Copy CD_FRAMESIZE bytes from src_bio into a destination page
 952  */
 953 static void pkt_copy_bio_data(struct bio *src_bio, int seg, int offs, struct page *dst_page, int dst_offs)
 954 {
 955         unsigned int copy_size = CD_FRAMESIZE;
 956
 957         while (copy_size > 0) {
 958                 struct bio_vec *src_bvl = bio_iovec_idx(src_bio, seg);
 959                 void *vfrom = kmap_atomic(src_bvl->bv_page) +
 960                         src_bvl->bv_offset + offs;
 961                 void *vto = page_address(dst_page) + dst_offs;
 962                 int len = min_t(int, copy_size, src_bvl->bv_len - offs);
 963
 964                 BUG_ON(len < 0);
 965                 memcpy(vto, vfrom, len);
 966                 kunmap_atomic(vfrom);
 967
 968                 seg++;
 969                 offs = 0;
 970                 dst_offs += len;
 971                 copy_size -= len;
 972         }
 973 }
 974
 975 /*
 976  * Copy all data for this packet to pkt->pages[], so that
 977  * a) The number of required segments for the write bio is minimized, which
 978  *    is necessary for some scsi controllers.
 979  * b) The data can be used as cache to avoid read requests if we receive a
 980  *    new write request for the same zone.
 981  */
 982 static void pkt_make_local_copy(struct packet_data *pkt, struct bio_vec *bvec)
 983 {
 984         int f, p, offs;
 985
 986         /* Copy all data to pkt->pages[] */
 987         p = 0;
 988         offs = 0;
 989         for (f = 0; f < pkt->frames; f++) {
 990                 if (bvec[f].bv_page != pkt->pages[p]) {
 991                         void *vfrom = kmap_atomic(bvec[f].bv_page) + bvec[f].bv_offset;
 992                         void *vto = page_address(pkt->pages[p]) + offs;
 993                         memcpy(vto, vfrom, CD_FRAMESIZE);
 994                         kunmap_atomic(vfrom);
 995                         bvec[f].bv_page = pkt->pages[p];
 996                         bvec[f].bv_offset = offs;
 997                 } else {
 998                         BUG_ON(bvec[f].bv_offset != offs);
 999                 }
1000                 offs += CD_FRAMESIZE;
1001                 if (offs >= PAGE_SIZE) {
1002                         offs = 0;
1003                         p++;
1004                 }
1005         }
1006 }
1007
1008 static void pkt_end_io_read(struct bio *bio, int err)
1009 {
1010         struct packet_data *pkt = bio->bi_private;
1011         struct pktcdvd_device *pd = pkt->pd;
1012         BUG_ON(!pd);
1013
1014         VPRINTK("pkt_end_io_read: bio=%p sec0=%llx sec=%llx err=%d\n", bio,
1015                 (unsigned long long)pkt->sector, (unsigned long long)bio->bi_sector, err);
1016
1017         if (err)
1018                 atomic_inc(&pkt->io_errors);
1019         if (atomic_dec_and_test(&pkt->io_wait)) {
1020                 atomic_inc(&pkt->run_sm);
1021                 wake_up(&pd->wqueue);
1022         }
1023         pkt_bio_finished(pd);
1024 }
1025
1026 static void pkt_end_io_packet_write(struct bio *bio, int err)
1027 {
1028         struct packet_data *pkt = bio->bi_private;
1029         struct pktcdvd_device *pd = pkt->pd;
1030         BUG_ON(!pd);
1031
1032         VPRINTK("pkt_end_io_packet_write: id=%d, err=%d\n", pkt->id, err);
1033
1034         pd->stats.pkt_ended++;
1035
1036         pkt_bio_finished(pd);
1037         atomic_dec(&pkt->io_wait);
1038         atomic_inc(&pkt->run_sm);
1039         wake_up(&pd->wqueue);
1040 }
1041
1042 /*
1043  * Schedule reads for the holes in a packet
1044  */
1045 static void pkt_gather_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1046 {
1047         int frames_read = 0;
1048         struct bio *bio;
1049         int f;
1050         char written[PACKET_MAX_SIZE];
1051
1052         BUG_ON(bio_list_empty(&pkt->orig_bios));
1053
1054         atomic_set(&pkt->io_wait, 0);
1055         atomic_set(&pkt->io_errors, 0);
1056
1057         /*
1058          * Figure out which frames we need to read before we can write.
1059          */
1060         memset(written, 0, sizeof(written));
1061         spin_lock(&pkt->lock);
1062         bio_list_for_each(bio, &pkt->orig_bios) {
1063                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1064                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1065                 pd->stats.secs_w += num_frames * (CD_FRAMESIZE >> 9);
1066                 BUG_ON(first_frame < 0);
1067                 BUG_ON(first_frame + num_frames > pkt->frames);
1068                 for (f = first_frame; f < first_frame + num_frames; f++)
1069                         written[f] = 1;
1070         }
1071         spin_unlock(&pkt->lock);
1072
1073         if (pkt->cache_valid) {
1074                 VPRINTK("pkt_gather_data: zone %llx cached\n",
1075                         (unsigned long long)pkt->sector);
1076                 goto out_account;
1077         }
1078
1079         /*
1080          * Schedule reads for missing parts of the packet.
1081          */
1082         for (f = 0; f < pkt->frames; f++) {
1083                 int p, offset;
1084
1085                 if (written[f])
1086                         continue;
1087
1088                 bio = pkt->r_bios[f];
1089                 bio_reset(bio);
1090                 bio->bi_sector = pkt->sector + f * (CD_FRAMESIZE >> 9);
1091                 bio->bi_bdev = pd->bdev;
1092                 bio->bi_end_io = pkt_end_io_read;
1093                 bio->bi_private = pkt;
1094
1095                 p = (f * CD_FRAMESIZE) / PAGE_SIZE;
1096                 offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1097                 VPRINTK("pkt_gather_data: Adding frame %d, page:%p offs:%d\n",
1098                         f, pkt->pages[p], offset);
1099                 if (!bio_add_page(bio, pkt->pages[p], CD_FRAMESIZE, offset))
1100                         BUG();
1101
1102                 atomic_inc(&pkt->io_wait);
1103                 bio->bi_rw = READ;
1104                 pkt_queue_bio(pd, bio);
1105                 frames_read++;
1106         }
1107
1108 out_account:
1109         VPRINTK("pkt_gather_data: need %d frames for zone %llx\n",
1110                 frames_read, (unsigned long long)pkt->sector);
1111         pd->stats.pkt_started++;
1112         pd->stats.secs_rg += frames_read * (CD_FRAMESIZE >> 9);
1113 }
1114
1115 /*
1116  * Find a packet matching zone, or the least recently used packet if
1117  * there is no match.
1118  */
1119 static struct packet_data *pkt_get_packet_data(struct pktcdvd_device *pd, int zone)
1120 {
1121         struct packet_data *pkt;
1122
1123         list_for_each_entry(pkt, &pd->cdrw.pkt_free_list, list) {
1124                 if (pkt->sector == zone || pkt->list.next == &pd->cdrw.pkt_free_list) {
1125                         list_del_init(&pkt->list);
1126                         if (pkt->sector != zone)
1127                                 pkt->cache_valid = 0;
1128                         return pkt;
1129                 }
1130         }
1131         BUG();
1132         return NULL;
1133 }
1134
1135 static void pkt_put_packet_data(struct pktcdvd_device *pd, struct packet_data *pkt)
1136 {
1137         if (pkt->cache_valid) {
1138                 list_add(&pkt->list, &pd->cdrw.pkt_free_list);
1139         } else {
1140                 list_add_tail(&pkt->list, &pd->cdrw.pkt_free_list);
1141         }
1142 }
1143
1144 /*
1145  * recover a failed write, query for relocation if possible
1146  *
1147  * returns 1 if recovery is possible, or 0 if not
1148  *
1149  */
1150 static int pkt_start_recovery(struct packet_data *pkt)
1151 {
1152         /*
1153          * FIXME. We need help from the file system to implement
1154          * recovery handling.
1155          */
1156         return 0;
1157 #if 0
1158         struct request *rq = pkt->rq;
1159         struct pktcdvd_device *pd = rq->rq_disk->private_data;
1160         struct block_device *pkt_bdev;
1161         struct super_block *sb = NULL;
1162         unsigned long old_block, new_block;
1163         sector_t new_sector;
1164
1165         pkt_bdev = bdget(kdev_t_to_nr(pd->pkt_dev));
1166         if (pkt_bdev) {
1167                 sb = get_super(pkt_bdev);
1168                 bdput(pkt_bdev);
1169         }
1170
1171         if (!sb)
1172                 return 0;
1173
1174         if (!sb->s_op->relocate_blocks)
1175                 goto out;
1176
1177         old_block = pkt->sector / (CD_FRAMESIZE >> 9);
1178         if (sb->s_op->relocate_blocks(sb, old_block, &new_block))
1179                 goto out;
1180
1181         new_sector = new_block * (CD_FRAMESIZE >> 9);
1182         pkt->sector = new_sector;
1183
1184         pkt->bio->bi_sector = new_sector;
1185         pkt->bio->bi_next = NULL;
1186         pkt->bio->bi_flags = 1 << BIO_UPTODATE;
1187         pkt->bio->bi_idx = 0;
1188
1189         BUG_ON(pkt->bio->bi_rw != REQ_WRITE);
1190         BUG_ON(pkt->bio->bi_vcnt != pkt->frames);
1191         BUG_ON(pkt->bio->bi_size != pkt->frames * CD_FRAMESIZE);
1192         BUG_ON(pkt->bio->bi_end_io != pkt_end_io_packet_write);
1193         BUG_ON(pkt->bio->bi_private != pkt);
1194
1195         drop_super(sb);
1196         return 1;
1197
1198 out:
1199         drop_super(sb);
1200         return 0;
1201 #endif
1202 }
1203
1204 static inline void pkt_set_state(struct packet_data *pkt, enum packet_data_state state)
1205 {
1206 #if PACKET_DEBUG > 1
1207         static const char *state_name[] = {
1208                 "IDLE", "WAITING", "READ_WAIT", "WRITE_WAIT", "RECOVERY", "FINISHED"
1209         };
1210         enum packet_data_state old_state = pkt->state;
1211         VPRINTK("pkt %2d : s=%6llx %s -> %s\n", pkt->id, (unsigned long long)pkt->sector,
1212                 state_name[old_state], state_name[state]);
1213 #endif
1214         pkt->state = state;
1215 }
1216
1217 /*
1218  * Scan the work queue to see if we can start a new packet.
1219  * returns non-zero if any work was done.
1220  */
1221 static int pkt_handle_queue(struct pktcdvd_device *pd)
1222 {
1223         struct packet_data *pkt, *p;
1224         struct bio *bio = NULL;
1225         sector_t zone = 0; /* Suppress gcc warning */
1226         struct pkt_rb_node *node, *first_node;
1227         struct rb_node *n;
1228         int wakeup;
1229
1230         VPRINTK("handle_queue\n");
1231
1232         atomic_set(&pd->scan_queue, 0);
1233
1234         if (list_empty(&pd->cdrw.pkt_free_list)) {
1235                 VPRINTK("handle_queue: no pkt\n");
1236                 return 0;
1237         }
1238
1239         /*
1240          * Try to find a zone we are not already working on.
1241          */
1242         spin_lock(&pd->lock);
1243         first_node = pkt_rbtree_find(pd, pd->current_sector);
1244         if (!first_node) {
1245                 n = rb_first(&pd->bio_queue);
1246                 if (n)
1247                         first_node = rb_entry(n, struct pkt_rb_node, rb_node);
1248         }
1249         node = first_node;
1250         while (node) {
1251                 bio = node->bio;
1252                 zone = ZONE(bio->bi_sector, pd);
1253                 list_for_each_entry(p, &pd->cdrw.pkt_active_list, list) {
1254                         if (p->sector == zone) {
1255                                 bio = NULL;
1256                                 goto try_next_bio;
1257                         }
1258                 }
1259                 break;
1260 try_next_bio:
1261                 node = pkt_rbtree_next(node);
1262                 if (!node) {
1263                         n = rb_first(&pd->bio_queue);
1264                         if (n)
1265                                 node = rb_entry(n, struct pkt_rb_node, rb_node);
1266                 }
1267                 if (node == first_node)
1268                         node = NULL;
1269         }
1270         spin_unlock(&pd->lock);
1271         if (!bio) {
1272                 VPRINTK("handle_queue: no bio\n");
1273                 return 0;
1274         }
1275
1276         pkt = pkt_get_packet_data(pd, zone);
1277
1278         pd->current_sector = zone + pd->settings.size;
1279         pkt->sector = zone;
1280         BUG_ON(pkt->frames != pd->settings.size >> 2);
1281         pkt->write_size = 0;
1282
1283         /*
1284          * Scan work queue for bios in the same zone and link them
1285          * to this packet.
1286          */
1287         spin_lock(&pd->lock);
1288         VPRINTK("pkt_handle_queue: looking for zone %llx\n", (unsigned long long)zone);
1289         while ((node = pkt_rbtree_find(pd, zone)) != NULL) {
1290                 bio = node->bio;
1291                 VPRINTK("pkt_handle_queue: found zone=%llx\n",
1292                         (unsigned long long)ZONE(bio->bi_sector, pd));
1293                 if (ZONE(bio->bi_sector, pd) != zone)
1294                         break;
1295                 pkt_rbtree_erase(pd, node);
1296                 spin_lock(&pkt->lock);
1297                 bio_list_add(&pkt->orig_bios, bio);
1298                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
1299                 spin_unlock(&pkt->lock);
1300         }
1301         /* check write congestion marks, and if bio_queue_size is
1302            below, wake up any waiters */
1303         wakeup = (pd->write_congestion_on > 0
1304                         && pd->bio_queue_size <= pd->write_congestion_off);
1305         spin_unlock(&pd->lock);
1306         if (wakeup) {
1307                 clear_bdi_congested(&pd->disk->queue->backing_dev_info,
1308                                         BLK_RW_ASYNC);
1309         }
1310
1311         pkt->sleep_time = max(PACKET_WAIT_TIME, 1);
1312         pkt_set_state(pkt, PACKET_WAITING_STATE);
1313         atomic_set(&pkt->run_sm, 1);
1314
1315         spin_lock(&pd->cdrw.active_list_lock);
1316         list_add(&pkt->list, &pd->cdrw.pkt_active_list);
1317         spin_unlock(&pd->cdrw.active_list_lock);
1318
1319         return 1;
1320 }
1321
1322 /*
1323  * Assemble a bio to write one packet and queue the bio for processing
1324  * by the underlying block device.
1325  */
1326 static void pkt_start_write(struct pktcdvd_device *pd, struct packet_data *pkt)
1327 {
1328         struct bio *bio;
1329         int f;
1330         int frames_write;
1331         struct bio_vec *bvec = pkt->w_bio->bi_io_vec;
1332
1333         for (f = 0; f < pkt->frames; f++) {
1334                 bvec[f].bv_page = pkt->pages[(f * CD_FRAMESIZE) / PAGE_SIZE];
1335                 bvec[f].bv_offset = (f * CD_FRAMESIZE) % PAGE_SIZE;
1336         }
1337
1338         /*
1339          * Fill-in bvec with data from orig_bios.
1340          */
1341         frames_write = 0;
1342         spin_lock(&pkt->lock);
1343         bio_list_for_each(bio, &pkt->orig_bios) {
1344                 int segment = bio->bi_idx;
1345                 int src_offs = 0;
1346                 int first_frame = (bio->bi_sector - pkt->sector) / (CD_FRAMESIZE >> 9);
1347                 int num_frames = bio->bi_size / CD_FRAMESIZE;
1348                 BUG_ON(first_frame < 0);
1349                 BUG_ON(first_frame + num_frames > pkt->frames);
1350                 for (f = first_frame; f < first_frame + num_frames; f++) {
1351                         struct bio_vec *src_bvl = bio_iovec_idx(bio, segment);
1352
1353                         while (src_offs >= src_bvl->bv_len) {
1354                                 src_offs -= src_bvl->bv_len;
1355                                 segment++;
1356                                 BUG_ON(segment >= bio->bi_vcnt);
1357                                 src_bvl = bio_iovec_idx(bio, segment);
1358                         }
1359
1360                         if (src_bvl->bv_len - src_offs >= CD_FRAMESIZE) {
1361                                 bvec[f].bv_page = src_bvl->bv_page;
1362                                 bvec[f].bv_offset = src_bvl->bv_offset + src_offs;
1363                         } else {
1364                                 pkt_copy_bio_data(bio, segment, src_offs,
1365                                                   bvec[f].bv_page, bvec[f].bv_offset);
1366                         }
1367                         src_offs += CD_FRAMESIZE;
1368                         frames_write++;
1369                 }
1370         }
1371         pkt_set_state(pkt, PACKET_WRITE_WAIT_STATE);
1372         spin_unlock(&pkt->lock);
1373
1374         VPRINTK("pkt_start_write: Writing %d frames for zone %llx\n",
1375                 frames_write, (unsigned long long)pkt->sector);
1376         BUG_ON(frames_write != pkt->write_size);
1377
1378         if (test_bit(PACKET_MERGE_SEGS, &pd->flags) || (pkt->write_size < pkt->frames)) {
1379                 pkt_make_local_copy(pkt, bvec);
1380                 pkt->cache_valid = 1;
1381         } else {
1382                 pkt->cache_valid = 0;
1383         }
1384
1385         /* Start the write request */
1386         bio_reset(pkt->w_bio);
1387         pkt->w_bio->bi_sector = pkt->sector;
1388         pkt->w_bio->bi_bdev = pd->bdev;
1389         pkt->w_bio->bi_end_io = pkt_end_io_packet_write;
1390         pkt->w_bio->bi_private = pkt;
1391         for (f = 0; f < pkt->frames; f++)
1392                 if (!bio_add_page(pkt->w_bio, bvec[f].bv_page, CD_FRAMESIZE, bvec[f].bv_offset))
1393                         BUG();
1394         VPRINTK(DRIVER_NAME": vcnt=%d\n", pkt->w_bio->bi_vcnt);
1395
1396         atomic_set(&pkt->io_wait, 1);
1397         pkt->w_bio->bi_rw = WRITE;
1398         pkt_queue_bio(pd, pkt->w_bio);
1399 }
1400
1401 static void pkt_finish_packet(struct packet_data *pkt, int uptodate)
1402 {
1403         struct bio *bio;
1404
1405         if (!uptodate)
1406                 pkt->cache_valid = 0;
1407
1408         /* Finish all bios corresponding to this packet */
1409         while ((bio = bio_list_pop(&pkt->orig_bios)))
1410                 bio_endio(bio, uptodate ? 0 : -EIO);
1411 }
1412
1413 static void pkt_run_state_machine(struct pktcdvd_device *pd, struct packet_data *pkt)
1414 {
1415         int uptodate;
1416
1417         VPRINTK("run_state_machine: pkt %d\n", pkt->id);
1418
1419         for (;;) {
1420                 switch (pkt->state) {
1421                 case PACKET_WAITING_STATE:
1422                         if ((pkt->write_size < pkt->frames) && (pkt->sleep_time > 0))
1423                                 return;
1424
1425                         pkt->sleep_time = 0;
1426                         pkt_gather_data(pd, pkt);
1427                         pkt_set_state(pkt, PACKET_READ_WAIT_STATE);
1428                         break;
1429
1430                 case PACKET_READ_WAIT_STATE:
1431                         if (atomic_read(&pkt->io_wait) > 0)
1432                                 return;
1433
1434                         if (atomic_read(&pkt->io_errors) > 0) {
1435                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1436                         } else {
1437                                 pkt_start_write(pd, pkt);
1438                         }
1439                         break;
1440
1441                 case PACKET_WRITE_WAIT_STATE:
1442                         if (atomic_read(&pkt->io_wait) > 0)
1443                                 return;
1444
1445                         if (test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags)) {
1446                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1447                         } else {
1448                                 pkt_set_state(pkt, PACKET_RECOVERY_STATE);
1449                         }
1450                         break;
1451
1452                 case PACKET_RECOVERY_STATE:
1453                         if (pkt_start_recovery(pkt)) {
1454                                 pkt_start_write(pd, pkt);
1455                         } else {
1456                                 VPRINTK("No recovery possible\n");
1457                                 pkt_set_state(pkt, PACKET_FINISHED_STATE);
1458                         }
1459                         break;
1460
1461                 case PACKET_FINISHED_STATE:
1462                         uptodate = test_bit(BIO_UPTODATE, &pkt->w_bio->bi_flags);
1463                         pkt_finish_packet(pkt, uptodate);
1464                         return;
1465
1466                 default:
1467                         BUG();
1468                         break;
1469                 }
1470         }
1471 }
1472
1473 static void pkt_handle_packets(struct pktcdvd_device *pd)
1474 {
1475         struct packet_data *pkt, *next;
1476
1477         VPRINTK("pkt_handle_packets\n");
1478
1479         /*
1480          * Run state machine for active packets
1481          */
1482         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1483                 if (atomic_read(&pkt->run_sm) > 0) {
1484                         atomic_set(&pkt->run_sm, 0);
1485                         pkt_run_state_machine(pd, pkt);
1486                 }
1487         }
1488
1489         /*
1490          * Move no longer active packets to the free list
1491          */
1492         spin_lock(&pd->cdrw.active_list_lock);
1493         list_for_each_entry_safe(pkt, next, &pd->cdrw.pkt_active_list, list) {
1494                 if (pkt->state == PACKET_FINISHED_STATE) {
1495                         list_del(&pkt->list);
1496                         pkt_put_packet_data(pd, pkt);
1497                         pkt_set_state(pkt, PACKET_IDLE_STATE);
1498                         atomic_set(&pd->scan_queue, 1);
1499                 }
1500         }
1501         spin_unlock(&pd->cdrw.active_list_lock);
1502 }
1503
1504 static void pkt_count_states(struct pktcdvd_device *pd, int *states)
1505 {
1506         struct packet_data *pkt;
1507         int i;
1508
1509         for (i = 0; i < PACKET_NUM_STATES; i++)
1510                 states[i] = 0;
1511
1512         spin_lock(&pd->cdrw.active_list_lock);
1513         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1514                 states[pkt->state]++;
1515         }
1516         spin_unlock(&pd->cdrw.active_list_lock);
1517 }
1518
1519 /*
1520  * kcdrwd is woken up when writes have been queued for one of our
1521  * registered devices
1522  */
1523 static int kcdrwd(void *foobar)
1524 {
1525         struct pktcdvd_device *pd = foobar;
1526         struct packet_data *pkt;
1527         long min_sleep_time, residue;
1528
1529         set_user_nice(current, -20);
1530         set_freezable();
1531
1532         for (;;) {
1533                 DECLARE_WAITQUEUE(wait, current);
1534
1535                 /*
1536                  * Wait until there is something to do
1537                  */
1538                 add_wait_queue(&pd->wqueue, &wait);
1539                 for (;;) {
1540                         set_current_state(TASK_INTERRUPTIBLE);
1541
1542                         /* Check if we need to run pkt_handle_queue */
1543                         if (atomic_read(&pd->scan_queue) > 0)
1544                                 goto work_to_do;
1545
1546                         /* Check if we need to run the state machine for some packet */
1547                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1548                                 if (atomic_read(&pkt->run_sm) > 0)
1549                                         goto work_to_do;
1550                         }
1551
1552                         /* Check if we need to process the iosched queues */
1553                         if (atomic_read(&pd->iosched.attention) != 0)
1554                                 goto work_to_do;
1555
1556                         /* Otherwise, go to sleep */
1557                         if (PACKET_DEBUG > 1) {
1558                                 int states[PACKET_NUM_STATES];
1559                                 pkt_count_states(pd, states);
1560                                 VPRINTK("kcdrwd: i:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
1561                                         states[0], states[1], states[2], states[3],
1562                                         states[4], states[5]);
1563                         }
1564
1565                         min_sleep_time = MAX_SCHEDULE_TIMEOUT;
1566                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1567                                 if (pkt->sleep_time && pkt->sleep_time < min_sleep_time)
1568                                         min_sleep_time = pkt->sleep_time;
1569                         }
1570
1571                         VPRINTK("kcdrwd: sleeping\n");
1572                         residue = schedule_timeout(min_sleep_time);
1573                         VPRINTK("kcdrwd: wake up\n");
1574
1575                         /* make swsusp happy with our thread */
1576                         try_to_freeze();
1577
1578                         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
1579                                 if (!pkt->sleep_time)
1580                                         continue;
1581                                 pkt->sleep_time -= min_sleep_time - residue;
1582                                 if (pkt->sleep_time <= 0) {
1583                                         pkt->sleep_time = 0;
1584                                         atomic_inc(&pkt->run_sm);
1585                                 }
1586                         }
1587
1588                         if (kthread_should_stop())
1589                                 break;
1590                 }
1591 work_to_do:
1592                 set_current_state(TASK_RUNNING);
1593                 remove_wait_queue(&pd->wqueue, &wait);
1594
1595                 if (kthread_should_stop())
1596                         break;
1597
1598                 /*
1599                  * if pkt_handle_queue returns true, we can queue
1600                  * another request.
1601                  */
1602                 while (pkt_handle_queue(pd))
1603                         ;
1604
1605                 /*
1606                  * Handle packet state machine
1607                  */
1608                 pkt_handle_packets(pd);
1609
1610                 /*
1611                  * Handle iosched queues
1612                  */
1613                 pkt_iosched_process_queue(pd);
1614         }
1615
1616         return 0;
1617 }
1618
1619 static void pkt_print_settings(struct pktcdvd_device *pd)
1620 {
1621         printk(DRIVER_NAME": %s packets, ", pd->settings.fp ? "Fixed" : "Variable");
1622         printk("%u blocks, ", pd->settings.size >> 2);
1623         printk("Mode-%c disc\n", pd->settings.block_mode == 8 ? '1' : '2');
1624 }
1625
1626 static int pkt_mode_sense(struct pktcdvd_device *pd, struct packet_command *cgc, int page_code, int page_control)
1627 {
1628         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1629
1630         cgc->cmd[0] = GPCMD_MODE_SENSE_10;
1631         cgc->cmd[2] = page_code | (page_control << 6);
1632         cgc->cmd[7] = cgc->buflen >> 8;
1633         cgc->cmd[8] = cgc->buflen & 0xff;
1634         cgc->data_direction = CGC_DATA_READ;
1635         return pkt_generic_packet(pd, cgc);
1636 }
1637
1638 static int pkt_mode_select(struct pktcdvd_device *pd, struct packet_command *cgc)
1639 {
1640         memset(cgc->cmd, 0, sizeof(cgc->cmd));
1641         memset(cgc->buffer, 0, 2);
1642         cgc->cmd[0] = GPCMD_MODE_SELECT_10;
1643         cgc->cmd[1] = 0x10;             /* PF */
1644         cgc->cmd[7] = cgc->buflen >> 8;
1645         cgc->cmd[8] = cgc->buflen & 0xff;
1646         cgc->data_direction = CGC_DATA_WRITE;
1647         return pkt_generic_packet(pd, cgc);
1648 }
1649
1650 static int pkt_get_disc_info(struct pktcdvd_device *pd, disc_information *di)
1651 {
1652         struct packet_command cgc;
1653         int ret;
1654
1655         /* set up command and get the disc info */
1656         init_cdrom_command(&cgc, di, sizeof(*di), CGC_DATA_READ);
1657         cgc.cmd[0] = GPCMD_READ_DISC_INFO;
1658         cgc.cmd[8] = cgc.buflen = 2;
1659         cgc.quiet = 1;
1660
1661         if ((ret = pkt_generic_packet(pd, &cgc)))
1662                 return ret;
1663
1664         /* not all drives have the same disc_info length, so requeue
1665          * packet with the length the drive tells us it can supply
1666          */
1667         cgc.buflen = be16_to_cpu(di->disc_information_length) +
1668                      sizeof(di->disc_information_length);
1669
1670         if (cgc.buflen > sizeof(disc_information))
1671                 cgc.buflen = sizeof(disc_information);
1672
1673         cgc.cmd[8] = cgc.buflen;
1674         return pkt_generic_packet(pd, &cgc);
1675 }
1676
1677 static int pkt_get_track_info(struct pktcdvd_device *pd, __u16 track, __u8 type, track_information *ti)
1678 {
1679         struct packet_command cgc;
1680         int ret;
1681
1682         init_cdrom_command(&cgc, ti, 8, CGC_DATA_READ);
1683         cgc.cmd[0] = GPCMD_READ_TRACK_RZONE_INFO;
1684         cgc.cmd[1] = type & 3;
1685         cgc.cmd[4] = (track & 0xff00) >> 8;
1686         cgc.cmd[5] = track & 0xff;
1687         cgc.cmd[8] = 8;
1688         cgc.quiet = 1;
1689
1690         if ((ret = pkt_generic_packet(pd, &cgc)))
1691                 return ret;
1692
1693         cgc.buflen = be16_to_cpu(ti->track_information_length) +
1694                      sizeof(ti->track_information_length);
1695
1696         if (cgc.buflen > sizeof(track_information))
1697                 cgc.buflen = sizeof(track_information);
1698
1699         cgc.cmd[8] = cgc.buflen;
1700         return pkt_generic_packet(pd, &cgc);
1701 }
1702
1703 static noinline_for_stack int pkt_get_last_written(struct pktcdvd_device *pd,
1704                                                 long *last_written)
1705 {
1706         disc_information di;
1707         track_information ti;
1708         __u32 last_track;
1709         int ret = -1;
1710
1711         if ((ret = pkt_get_disc_info(pd, &di)))
1712                 return ret;
1713
1714         last_track = (di.last_track_msb << 8) | di.last_track_lsb;
1715         if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1716                 return ret;
1717
1718         /* if this track is blank, try the previous. */
1719         if (ti.blank) {
1720                 last_track--;
1721                 if ((ret = pkt_get_track_info(pd, last_track, 1, &ti)))
1722                         return ret;
1723         }
1724
1725         /* if last recorded field is valid, return it. */
1726         if (ti.lra_v) {
1727                 *last_written = be32_to_cpu(ti.last_rec_address);
1728         } else {
1729                 /* make it up instead */
1730                 *last_written = be32_to_cpu(ti.track_start) +
1731                                 be32_to_cpu(ti.track_size);
1732                 if (ti.free_blocks)
1733                         *last_written -= (be32_to_cpu(ti.free_blocks) + 7);
1734         }
1735         return 0;
1736 }
1737
1738 /*
1739  * write mode select package based on pd->settings
1740  */
1741 static noinline_for_stack int pkt_set_write_settings(struct pktcdvd_device *pd)
1742 {
1743         struct packet_command cgc;
1744         struct request_sense sense;
1745         write_param_page *wp;
1746         char buffer[128];
1747         int ret, size;
1748
1749         /* doesn't apply to DVD+RW or DVD-RAM */
1750         if ((pd->mmc3_profile == 0x1a) || (pd->mmc3_profile == 0x12))
1751                 return 0;
1752
1753         memset(buffer, 0, sizeof(buffer));
1754         init_cdrom_command(&cgc, buffer, sizeof(*wp), CGC_DATA_READ);
1755         cgc.sense = &sense;
1756         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1757                 pkt_dump_sense(&cgc);
1758                 return ret;
1759         }
1760
1761         size = 2 + ((buffer[0] << 8) | (buffer[1] & 0xff));
1762         pd->mode_offset = (buffer[6] << 8) | (buffer[7] & 0xff);
1763         if (size > sizeof(buffer))
1764                 size = sizeof(buffer);
1765
1766         /*
1767          * now get it all
1768          */
1769         init_cdrom_command(&cgc, buffer, size, CGC_DATA_READ);
1770         cgc.sense = &sense;
1771         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WRITE_PARMS_PAGE, 0))) {
1772                 pkt_dump_sense(&cgc);
1773                 return ret;
1774         }
1775
1776         /*
1777          * write page is offset header + block descriptor length
1778          */
1779         wp = (write_param_page *) &buffer[sizeof(struct mode_page_header) + pd->mode_offset];
1780
1781         wp->fp = pd->settings.fp;
1782         wp->track_mode = pd->settings.track_mode;
1783         wp->write_type = pd->settings.write_type;
1784         wp->data_block_type = pd->settings.block_mode;
1785
1786         wp->multi_session = 0;
1787
1788 #ifdef PACKET_USE_LS
1789         wp->link_size = 7;
1790         wp->ls_v = 1;
1791 #endif
1792
1793         if (wp->data_block_type == PACKET_BLOCK_MODE1) {
1794                 wp->session_format = 0;
1795                 wp->subhdr2 = 0x20;
1796         } else if (wp->data_block_type == PACKET_BLOCK_MODE2) {
1797                 wp->session_format = 0x20;
1798                 wp->subhdr2 = 8;
1799 #if 0
1800                 wp->mcn[0] = 0x80;
1801                 memcpy(&wp->mcn[1], PACKET_MCN, sizeof(wp->mcn) - 1);
1802 #endif
1803         } else {
1804                 /*
1805                  * paranoia
1806                  */
1807                 printk(DRIVER_NAME": write mode wrong %d\n", wp->data_block_type);
1808                 return 1;
1809         }
1810         wp->packet_size = cpu_to_be32(pd->settings.size >> 2);
1811
1812         cgc.buflen = cgc.cmd[8] = size;
1813         if ((ret = pkt_mode_select(pd, &cgc))) {
1814                 pkt_dump_sense(&cgc);
1815                 return ret;
1816         }
1817
1818         pkt_print_settings(pd);
1819         return 0;
1820 }
1821
1822 /*
1823  * 1 -- we can write to this track, 0 -- we can't
1824  */
1825 static int pkt_writable_track(struct pktcdvd_device *pd, track_information *ti)
1826 {
1827         switch (pd->mmc3_profile) {
1828                 case 0x1a: /* DVD+RW */
1829                 case 0x12: /* DVD-RAM */
1830                         /* The track is always writable on DVD+RW/DVD-RAM */
1831                         return 1;
1832                 default:
1833                         break;
1834         }
1835
1836         if (!ti->packet || !ti->fp)
1837                 return 0;
1838
1839         /*
1840          * "good" settings as per Mt Fuji.
1841          */
1842         if (ti->rt == 0 && ti->blank == 0)
1843                 return 1;
1844
1845         if (ti->rt == 0 && ti->blank == 1)
1846                 return 1;
1847
1848         if (ti->rt == 1 && ti->blank == 0)
1849                 return 1;
1850
1851         printk(DRIVER_NAME": bad state %d-%d-%d\n", ti->rt, ti->blank, ti->packet);
1852         return 0;
1853 }
1854
1855 /*
1856  * 1 -- we can write to this disc, 0 -- we can't
1857  */
1858 static int pkt_writable_disc(struct pktcdvd_device *pd, disc_information *di)
1859 {
1860         switch (pd->mmc3_profile) {
1861                 case 0x0a: /* CD-RW */
1862                 case 0xffff: /* MMC3 not supported */
1863                         break;
1864                 case 0x1a: /* DVD+RW */
1865                 case 0x13: /* DVD-RW */
1866                 case 0x12: /* DVD-RAM */
1867                         return 1;
1868                 default:
1869                         VPRINTK(DRIVER_NAME": Wrong disc profile (%x)\n", pd->mmc3_profile);
1870                         return 0;
1871         }
1872
1873         /*
1874          * for disc type 0xff we should probably reserve a new track.
1875          * but i'm not sure, should we leave this to user apps? probably.
1876          */
1877         if (di->disc_type == 0xff) {
1878                 printk(DRIVER_NAME": Unknown disc. No track?\n");
1879                 return 0;
1880         }
1881
1882         if (di->disc_type != 0x20 && di->disc_type != 0) {
1883                 printk(DRIVER_NAME": Wrong disc type (%x)\n", di->disc_type);
1884                 return 0;
1885         }
1886
1887         if (di->erasable == 0) {
1888                 printk(DRIVER_NAME": Disc not erasable\n");
1889                 return 0;
1890         }
1891
1892         if (di->border_status == PACKET_SESSION_RESERVED) {
1893                 printk(DRIVER_NAME": Can't write to last track (reserved)\n");
1894                 return 0;
1895         }
1896
1897         return 1;
1898 }
1899
1900 static noinline_for_stack int pkt_probe_settings(struct pktcdvd_device *pd)
1901 {
1902         struct packet_command cgc;
1903         unsigned char buf[12];
1904         disc_information di;
1905         track_information ti;
1906         int ret, track;
1907
1908         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
1909         cgc.cmd[0] = GPCMD_GET_CONFIGURATION;
1910         cgc.cmd[8] = 8;
1911         ret = pkt_generic_packet(pd, &cgc);
1912         pd->mmc3_profile = ret ? 0xffff : buf[6] << 8 | buf[7];
1913
1914         memset(&di, 0, sizeof(disc_information));
1915         memset(&ti, 0, sizeof(track_information));
1916
1917         if ((ret = pkt_get_disc_info(pd, &di))) {
1918                 printk("failed get_disc\n");
1919                 return ret;
1920         }
1921
1922         if (!pkt_writable_disc(pd, &di))
1923                 return -EROFS;
1924
1925         pd->type = di.erasable ? PACKET_CDRW : PACKET_CDR;
1926
1927         track = 1; /* (di.last_track_msb << 8) | di.last_track_lsb; */
1928         if ((ret = pkt_get_track_info(pd, track, 1, &ti))) {
1929                 printk(DRIVER_NAME": failed get_track\n");
1930                 return ret;
1931         }
1932
1933         if (!pkt_writable_track(pd, &ti)) {
1934                 printk(DRIVER_NAME": can't write to this track\n");
1935                 return -EROFS;
1936         }
1937
1938         /*
1939          * we keep packet size in 512 byte units, makes it easier to
1940          * deal with request calculations.
1941          */
1942         pd->settings.size = be32_to_cpu(ti.fixed_packet_size) << 2;
1943         if (pd->settings.size == 0) {
1944                 printk(DRIVER_NAME": detected zero packet size!\n");
1945                 return -ENXIO;
1946         }
1947         if (pd->settings.size > PACKET_MAX_SECTORS) {
1948                 printk(DRIVER_NAME": packet size is too big\n");
1949                 return -EROFS;
1950         }
1951         pd->settings.fp = ti.fp;
1952         pd->offset = (be32_to_cpu(ti.track_start) << 2) & (pd->settings.size - 1);
1953
1954         if (ti.nwa_v) {
1955                 pd->nwa = be32_to_cpu(ti.next_writable);
1956                 set_bit(PACKET_NWA_VALID, &pd->flags);
1957         }
1958
1959         /*
1960          * in theory we could use lra on -RW media as well and just zero
1961          * blocks that haven't been written yet, but in practice that
1962          * is just a no-go. we'll use that for -R, naturally.
1963          */
1964         if (ti.lra_v) {
1965                 pd->lra = be32_to_cpu(ti.last_rec_address);
1966                 set_bit(PACKET_LRA_VALID, &pd->flags);
1967         } else {
1968                 pd->lra = 0xffffffff;
1969                 set_bit(PACKET_LRA_VALID, &pd->flags);
1970         }
1971
1972         /*
1973          * fine for now
1974          */
1975         pd->settings.link_loss = 7;
1976         pd->settings.write_type = 0;    /* packet */
1977         pd->settings.track_mode = ti.track_mode;
1978
1979         /*
1980          * mode1 or mode2 disc
1981          */
1982         switch (ti.data_mode) {
1983                 case PACKET_MODE1:
1984                         pd->settings.block_mode = PACKET_BLOCK_MODE1;
1985                         break;
1986                 case PACKET_MODE2:
1987                         pd->settings.block_mode = PACKET_BLOCK_MODE2;
1988                         break;
1989                 default:
1990                         printk(DRIVER_NAME": unknown data mode\n");
1991                         return -EROFS;
1992         }
1993         return 0;
1994 }
1995
1996 /*
1997  * enable/disable write caching on drive
1998  */
1999 static noinline_for_stack int pkt_write_caching(struct pktcdvd_device *pd,
2000                                                 int set)
2001 {
2002         struct packet_command cgc;
2003         struct request_sense sense;
2004         unsigned char buf[64];
2005         int ret;
2006
2007         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_READ);
2008         cgc.sense = &sense;
2009         cgc.buflen = pd->mode_offset + 12;
2010
2011         /*
2012          * caching mode page might not be there, so quiet this command
2013          */
2014         cgc.quiet = 1;
2015
2016         if ((ret = pkt_mode_sense(pd, &cgc, GPMODE_WCACHING_PAGE, 0)))
2017                 return ret;
2018
2019         buf[pd->mode_offset + 10] |= (!!set << 2);
2020
2021         cgc.buflen = cgc.cmd[8] = 2 + ((buf[0] << 8) | (buf[1] & 0xff));
2022         ret = pkt_mode_select(pd, &cgc);
2023         if (ret) {
2024                 printk(DRIVER_NAME": write caching control failed\n");
2025                 pkt_dump_sense(&cgc);
2026         } else if (!ret && set)
2027                 printk(DRIVER_NAME": enabled write caching on %s\n", pd->name);
2028         return ret;
2029 }
2030
2031 static int pkt_lock_door(struct pktcdvd_device *pd, int lockflag)
2032 {
2033         struct packet_command cgc;
2034
2035         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2036         cgc.cmd[0] = GPCMD_PREVENT_ALLOW_MEDIUM_REMOVAL;
2037         cgc.cmd[4] = lockflag ? 1 : 0;
2038         return pkt_generic_packet(pd, &cgc);
2039 }
2040
2041 /*
2042  * Returns drive maximum write speed
2043  */
2044 static noinline_for_stack int pkt_get_max_speed(struct pktcdvd_device *pd,
2045                                                 unsigned *write_speed)
2046 {
2047         struct packet_command cgc;
2048         struct request_sense sense;
2049         unsigned char buf[256+18];
2050         unsigned char *cap_buf;
2051         int ret, offset;
2052
2053         cap_buf = &buf[sizeof(struct mode_page_header) + pd->mode_offset];
2054         init_cdrom_command(&cgc, buf, sizeof(buf), CGC_DATA_UNKNOWN);
2055         cgc.sense = &sense;
2056
2057         ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2058         if (ret) {
2059                 cgc.buflen = pd->mode_offset + cap_buf[1] + 2 +
2060                              sizeof(struct mode_page_header);
2061                 ret = pkt_mode_sense(pd, &cgc, GPMODE_CAPABILITIES_PAGE, 0);
2062                 if (ret) {
2063                         pkt_dump_sense(&cgc);
2064                         return ret;
2065                 }
2066         }
2067
2068         offset = 20;                        /* Obsoleted field, used by older drives */
2069         if (cap_buf[1] >= 28)
2070                 offset = 28;                /* Current write speed selected */
2071         if (cap_buf[1] >= 30) {
2072                 /* If the drive reports at least one "Logical Unit Write
2073                  * Speed Performance Descriptor Block", use the information
2074                  * in the first block. (contains the highest speed)
2075                  */
2076                 int num_spdb = (cap_buf[30] << 8) + cap_buf[31];
2077                 if (num_spdb > 0)
2078                         offset = 34;
2079         }
2080
2081         *write_speed = (cap_buf[offset] << 8) | cap_buf[offset + 1];
2082         return 0;
2083 }
2084
2085 /* These tables from cdrecord - I don't have orange book */
2086 /* standard speed CD-RW (1-4x) */
2087 static char clv_to_speed[16] = {
2088         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2089            0, 2, 4, 6, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2090 };
2091 /* high speed CD-RW (-10x) */
2092 static char hs_clv_to_speed[16] = {
2093         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2094            0, 2, 4, 6, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
2095 };
2096 /* ultra high speed CD-RW */
2097 static char us_clv_to_speed[16] = {
2098         /* 0  1  2  3  4  5  6  7  8  9 10 11 12 13 14 15 */
2099            0, 2, 4, 8, 0, 0,16, 0,24,32,40,48, 0, 0, 0, 0
2100 };
2101
2102 /*
2103  * reads the maximum media speed from ATIP
2104  */
2105 static noinline_for_stack int pkt_media_speed(struct pktcdvd_device *pd,
2106                                                 unsigned *speed)
2107 {
2108         struct packet_command cgc;
2109         struct request_sense sense;
2110         unsigned char buf[64];
2111         unsigned int size, st, sp;
2112         int ret;
2113
2114         init_cdrom_command(&cgc, buf, 2, CGC_DATA_READ);
2115         cgc.sense = &sense;
2116         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2117         cgc.cmd[1] = 2;
2118         cgc.cmd[2] = 4; /* READ ATIP */
2119         cgc.cmd[8] = 2;
2120         ret = pkt_generic_packet(pd, &cgc);
2121         if (ret) {
2122                 pkt_dump_sense(&cgc);
2123                 return ret;
2124         }
2125         size = ((unsigned int) buf[0]<<8) + buf[1] + 2;
2126         if (size > sizeof(buf))
2127                 size = sizeof(buf);
2128
2129         init_cdrom_command(&cgc, buf, size, CGC_DATA_READ);
2130         cgc.sense = &sense;
2131         cgc.cmd[0] = GPCMD_READ_TOC_PMA_ATIP;
2132         cgc.cmd[1] = 2;
2133         cgc.cmd[2] = 4;
2134         cgc.cmd[8] = size;
2135         ret = pkt_generic_packet(pd, &cgc);
2136         if (ret) {
2137                 pkt_dump_sense(&cgc);
2138                 return ret;
2139         }
2140
2141         if (!(buf[6] & 0x40)) {
2142                 printk(DRIVER_NAME": Disc type is not CD-RW\n");
2143                 return 1;
2144         }
2145         if (!(buf[6] & 0x4)) {
2146                 printk(DRIVER_NAME": A1 values on media are not valid, maybe not CDRW?\n");
2147                 return 1;
2148         }
2149
2150         st = (buf[6] >> 3) & 0x7; /* disc sub-type */
2151
2152         sp = buf[16] & 0xf; /* max speed from ATIP A1 field */
2153
2154         /* Info from cdrecord */
2155         switch (st) {
2156                 case 0: /* standard speed */
2157                         *speed = clv_to_speed[sp];
2158                         break;
2159                 case 1: /* high speed */
2160                         *speed = hs_clv_to_speed[sp];
2161                         break;
2162                 case 2: /* ultra high speed */
2163                         *speed = us_clv_to_speed[sp];
2164                         break;
2165                 default:
2166                         printk(DRIVER_NAME": Unknown disc sub-type %d\n",st);
2167                         return 1;
2168         }
2169         if (*speed) {
2170                 printk(DRIVER_NAME": Max. media speed: %d\n",*speed);
2171                 return 0;
2172         } else {
2173                 printk(DRIVER_NAME": Unknown speed %d for sub-type %d\n",sp,st);
2174                 return 1;
2175         }
2176 }
2177
2178 static noinline_for_stack int pkt_perform_opc(struct pktcdvd_device *pd)
2179 {
2180         struct packet_command cgc;
2181         struct request_sense sense;
2182         int ret;
2183
2184         VPRINTK(DRIVER_NAME": Performing OPC\n");
2185
2186         init_cdrom_command(&cgc, NULL, 0, CGC_DATA_NONE);
2187         cgc.sense = &sense;
2188         cgc.timeout = 60*HZ;
2189         cgc.cmd[0] = GPCMD_SEND_OPC;
2190         cgc.cmd[1] = 1;
2191         if ((ret = pkt_generic_packet(pd, &cgc)))
2192                 pkt_dump_sense(&cgc);
2193         return ret;
2194 }
2195
2196 static int pkt_open_write(struct pktcdvd_device *pd)
2197 {
2198         int ret;
2199         unsigned int write_speed, media_write_speed, read_speed;
2200
2201         if ((ret = pkt_probe_settings(pd))) {
2202                 VPRINTK(DRIVER_NAME": %s failed probe\n", pd->name);
2203                 return ret;
2204         }
2205
2206         if ((ret = pkt_set_write_settings(pd))) {
2207                 DPRINTK(DRIVER_NAME": %s failed saving write settings\n", pd->name);
2208                 return -EIO;
2209         }
2210
2211         pkt_write_caching(pd, USE_WCACHING);
2212
2213         if ((ret = pkt_get_max_speed(pd, &write_speed)))
2214                 write_speed = 16 * 177;
2215         switch (pd->mmc3_profile) {
2216                 case 0x13: /* DVD-RW */
2217                 case 0x1a: /* DVD+RW */
2218                 case 0x12: /* DVD-RAM */
2219                         DPRINTK(DRIVER_NAME": write speed %ukB/s\n", write_speed);
2220                         break;
2221                 default:
2222                         if ((ret = pkt_media_speed(pd, &media_write_speed)))
2223                                 media_write_speed = 16;
2224                         write_speed = min(write_speed, media_write_speed * 177);
2225                         DPRINTK(DRIVER_NAME": write speed %ux\n", write_speed / 176);
2226                         break;
2227         }
2228         read_speed = write_speed;
2229
2230         if ((ret = pkt_set_speed(pd, write_speed, read_speed))) {
2231                 DPRINTK(DRIVER_NAME": %s couldn't set write speed\n", pd->name);
2232                 return -EIO;
2233         }
2234         pd->write_speed = write_speed;
2235         pd->read_speed = read_speed;
2236
2237         if ((ret = pkt_perform_opc(pd))) {
2238                 DPRINTK(DRIVER_NAME": %s Optimum Power Calibration failed\n", pd->name);
2239         }
2240
2241         return 0;
2242 }
2243
2244 /*
2245  * called at open time.
2246  */
2247 static int pkt_open_dev(struct pktcdvd_device *pd, fmode_t write)
2248 {
2249         int ret;
2250         long lba;
2251         struct request_queue *q;
2252
2253         /*
2254          * We need to re-open the cdrom device without O_NONBLOCK to be able
2255          * to read/write from/to it. It is already opened in O_NONBLOCK mode
2256          * so bdget() can't fail.
2257          */
2258         bdget(pd->bdev->bd_dev);
2259         if ((ret = blkdev_get(pd->bdev, FMODE_READ | FMODE_EXCL, pd)))
2260                 goto out;
2261
2262         if ((ret = pkt_get_last_written(pd, &lba))) {
2263                 printk(DRIVER_NAME": pkt_get_last_written failed\n");
2264                 goto out_putdev;
2265         }
2266
2267         set_capacity(pd->disk, lba << 2);
2268         set_capacity(pd->bdev->bd_disk, lba << 2);
2269         bd_set_size(pd->bdev, (loff_t)lba << 11);
2270
2271         q = bdev_get_queue(pd->bdev);
2272         if (write) {
2273                 if ((ret = pkt_open_write(pd)))
2274                         goto out_putdev;
2275                 /*
2276                  * Some CDRW drives can not handle writes larger than one packet,
2277                  * even if the size is a multiple of the packet size.
2278                  */
2279                 spin_lock_irq(q->queue_lock);
2280                 blk_queue_max_hw_sectors(q, pd->settings.size);
2281                 spin_unlock_irq(q->queue_lock);
2282                 set_bit(PACKET_WRITABLE, &pd->flags);
2283         } else {
2284                 pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2285                 clear_bit(PACKET_WRITABLE, &pd->flags);
2286         }
2287
2288         if ((ret = pkt_set_segment_merging(pd, q)))
2289                 goto out_putdev;
2290
2291         if (write) {
2292                 if (!pkt_grow_pktlist(pd, CONFIG_CDROM_PKTCDVD_BUFFERS)) {
2293                         printk(DRIVER_NAME": not enough memory for buffers\n");
2294                         ret = -ENOMEM;
2295                         goto out_putdev;
2296                 }
2297                 printk(DRIVER_NAME": %lukB available on disc\n", lba << 1);
2298         }
2299
2300         return 0;
2301
2302 out_putdev:
2303         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2304 out:
2305         return ret;
2306 }
2307
2308 /*
2309  * called when the device is closed. makes sure that the device flushes
2310  * the internal cache before we close.
2311  */
2312 static void pkt_release_dev(struct pktcdvd_device *pd, int flush)
2313 {
2314         if (flush && pkt_flush_cache(pd))
2315                 DPRINTK(DRIVER_NAME": %s not flushing cache\n", pd->name);
2316
2317         pkt_lock_door(pd, 0);
2318
2319         pkt_set_speed(pd, MAX_SPEED, MAX_SPEED);
2320         blkdev_put(pd->bdev, FMODE_READ | FMODE_EXCL);
2321
2322         pkt_shrink_pktlist(pd);
2323 }
2324
2325 static struct pktcdvd_device *pkt_find_dev_from_minor(unsigned int dev_minor)
2326 {
2327         if (dev_minor >= MAX_WRITERS)
2328                 return NULL;
2329         return pkt_devs[dev_minor];
2330 }
2331
2332 static int pkt_open(struct block_device *bdev, fmode_t mode)
2333 {
2334         struct pktcdvd_device *pd = NULL;
2335         int ret;
2336
2337         VPRINTK(DRIVER_NAME": entering open\n");
2338
2339         mutex_lock(&pktcdvd_mutex);
2340         mutex_lock(&ctl_mutex);
2341         pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
2342         if (!pd) {
2343                 ret = -ENODEV;
2344                 goto out;
2345         }
2346         BUG_ON(pd->refcnt < 0);
2347
2348         pd->refcnt++;
2349         if (pd->refcnt > 1) {
2350                 if ((mode & FMODE_WRITE) &&
2351                     !test_bit(PACKET_WRITABLE, &pd->flags)) {
2352                         ret = -EBUSY;
2353                         goto out_dec;
2354                 }
2355         } else {
2356                 ret = pkt_open_dev(pd, mode & FMODE_WRITE);
2357                 if (ret)
2358                         goto out_dec;
2359                 /*
2360                  * needed here as well, since ext2 (among others) may change
2361                  * the blocksize at mount time
2362                  */
2363                 set_blocksize(bdev, CD_FRAMESIZE);
2364         }
2365
2366         mutex_unlock(&ctl_mutex);
2367         mutex_unlock(&pktcdvd_mutex);
2368         return 0;
2369
2370 out_dec:
2371         pd->refcnt--;
2372 out:
2373         VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
2374         mutex_unlock(&ctl_mutex);
2375         mutex_unlock(&pktcdvd_mutex);
2376         return ret;
2377 }
2378
2379 static int pkt_close(struct gendisk *disk, fmode_t mode)
2380 {
2381         struct pktcdvd_device *pd = disk->private_data;
2382         int ret = 0;
2383
2384         mutex_lock(&pktcdvd_mutex);
2385         mutex_lock(&ctl_mutex);
2386         pd->refcnt--;
2387         BUG_ON(pd->refcnt < 0);
2388         if (pd->refcnt == 0) {
2389                 int flush = test_bit(PACKET_WRITABLE, &pd->flags);
2390                 pkt_release_dev(pd, flush);
2391         }
2392         mutex_unlock(&ctl_mutex);
2393         mutex_unlock(&pktcdvd_mutex);
2394         return ret;
2395 }
2396
2397
2398 static void pkt_end_io_read_cloned(struct bio *bio, int err)
2399 {
2400         struct packet_stacked_data *psd = bio->bi_private;
2401         struct pktcdvd_device *pd = psd->pd;
2402
2403         bio_put(bio);
2404         bio_endio(psd->bio, err);
2405         mempool_free(psd, psd_pool);
2406         pkt_bio_finished(pd);
2407 }
2408
2409 static void pkt_make_request(struct request_queue *q, struct bio *bio)
2410 {
2411         struct pktcdvd_device *pd;
2412         char b[BDEVNAME_SIZE];
2413         sector_t zone;
2414         struct packet_data *pkt;
2415         int was_empty, blocked_bio;
2416         struct pkt_rb_node *node;
2417
2418         pd = q->queuedata;
2419         if (!pd) {
2420                 printk(DRIVER_NAME": %s incorrect request queue\n", bdevname(bio->bi_bdev, b));
2421                 goto end_io;
2422         }
2423
2424         /*
2425          * Clone READ bios so we can have our own bi_end_io callback.
2426          */
2427         if (bio_data_dir(bio) == READ) {
2428                 struct bio *cloned_bio = bio_clone(bio, GFP_NOIO);
2429                 struct packet_stacked_data *psd = mempool_alloc(psd_pool, GFP_NOIO);
2430
2431                 psd->pd = pd;
2432                 psd->bio = bio;
2433                 cloned_bio->bi_bdev = pd->bdev;
2434                 cloned_bio->bi_private = psd;
2435                 cloned_bio->bi_end_io = pkt_end_io_read_cloned;
2436                 pd->stats.secs_r += bio->bi_size >> 9;
2437                 pkt_queue_bio(pd, cloned_bio);
2438                 return;
2439         }
2440
2441         if (!test_bit(PACKET_WRITABLE, &pd->flags)) {
2442                 printk(DRIVER_NAME": WRITE for ro device %s (%llu)\n",
2443                         pd->name, (unsigned long long)bio->bi_sector);
2444                 goto end_io;
2445         }
2446
2447         if (!bio->bi_size || (bio->bi_size % CD_FRAMESIZE)) {
2448                 printk(DRIVER_NAME": wrong bio size\n");
2449                 goto end_io;
2450         }
2451
2452         blk_queue_bounce(q, &bio);
2453
2454         zone = ZONE(bio->bi_sector, pd);
2455         VPRINTK("pkt_make_request: start = %6llx stop = %6llx\n",
2456                 (unsigned long long)bio->bi_sector,
2457                 (unsigned long long)(bio->bi_sector + bio_sectors(bio)));
2458
2459         /* Check if we have to split the bio */
2460         {
2461                 struct bio_pair *bp;
2462                 sector_t last_zone;
2463                 int first_sectors;
2464
2465                 last_zone = ZONE(bio->bi_sector + bio_sectors(bio) - 1, pd);
2466                 if (last_zone != zone) {
2467                         BUG_ON(last_zone != zone + pd->settings.size);
2468                         first_sectors = last_zone - bio->bi_sector;
2469                         bp = bio_split(bio, first_sectors);
2470                         BUG_ON(!bp);
2471                         pkt_make_request(q, &bp->bio1);
2472                         pkt_make_request(q, &bp->bio2);
2473                         bio_pair_release(bp);
2474                         return;
2475                 }
2476         }
2477
2478         /*
2479          * If we find a matching packet in state WAITING or READ_WAIT, we can
2480          * just append this bio to that packet.
2481          */
2482         spin_lock(&pd->cdrw.active_list_lock);
2483         blocked_bio = 0;
2484         list_for_each_entry(pkt, &pd->cdrw.pkt_active_list, list) {
2485                 if (pkt->sector == zone) {
2486                         spin_lock(&pkt->lock);
2487                         if ((pkt->state == PACKET_WAITING_STATE) ||
2488                             (pkt->state == PACKET_READ_WAIT_STATE)) {
2489                                 bio_list_add(&pkt->orig_bios, bio);
2490                                 pkt->write_size += bio->bi_size / CD_FRAMESIZE;
2491                                 if ((pkt->write_size >= pkt->frames) &&
2492                                     (pkt->state == PACKET_WAITING_STATE)) {
2493                                         atomic_inc(&pkt->run_sm);
2494                                         wake_up(&pd->wqueue);
2495                                 }
2496                                 spin_unlock(&pkt->lock);
2497                                 spin_unlock(&pd->cdrw.active_list_lock);
2498                                 return;
2499                         } else {
2500                                 blocked_bio = 1;
2501                         }
2502                         spin_unlock(&pkt->lock);
2503                 }
2504         }
2505         spin_unlock(&pd->cdrw.active_list_lock);
2506
2507         /*
2508          * Test if there is enough room left in the bio work queue
2509          * (queue size >= congestion on mark).
2510          * If not, wait till the work queue size is below the congestion off mark.
2511          */
2512         spin_lock(&pd->lock);
2513         if (pd->write_congestion_on > 0
2514             && pd->bio_queue_size >= pd->write_congestion_on) {
2515                 set_bdi_congested(&q->backing_dev_info, BLK_RW_ASYNC);
2516                 do {
2517                         spin_unlock(&pd->lock);
2518                         congestion_wait(BLK_RW_ASYNC, HZ);
2519                         spin_lock(&pd->lock);
2520                 } while(pd->bio_queue_size > pd->write_congestion_off);
2521         }
2522         spin_unlock(&pd->lock);
2523
2524         /*
2525          * No matching packet found. Store the bio in the work queue.
2526          */
2527         node = mempool_alloc(pd->rb_pool, GFP_NOIO);
2528         node->bio = bio;
2529         spin_lock(&pd->lock);
2530         BUG_ON(pd->bio_queue_size < 0);
2531         was_empty = (pd->bio_queue_size == 0);
2532         pkt_rbtree_insert(pd, node);
2533         spin_unlock(&pd->lock);
2534
2535         /*
2536          * Wake up the worker thread.
2537          */
2538         atomic_set(&pd->scan_queue, 1);
2539         if (was_empty) {
2540                 /* This wake_up is required for correct operation */
2541                 wake_up(&pd->wqueue);
2542         } else if (!list_empty(&pd->cdrw.pkt_free_list) && !blocked_bio) {
2543                 /*
2544                  * This wake up is not required for correct operation,
2545                  * but improves performance in some cases.
2546                  */
2547                 wake_up(&pd->wqueue);
2548         }
2549         return;
2550 end_io:
2551         bio_io_error(bio);
2552 }
2553
2554
2555
2556 static int pkt_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
2557                           struct bio_vec *bvec)
2558 {
2559         struct pktcdvd_device *pd = q->queuedata;
2560         sector_t zone = ZONE(bmd->bi_sector, pd);
2561         int used = ((bmd->bi_sector - zone) << 9) + bmd->bi_size;
2562         int remaining = (pd->settings.size << 9) - used;
2563         int remaining2;
2564
2565         /*
2566          * A bio <= PAGE_SIZE must be allowed. If it crosses a packet
2567          * boundary, pkt_make_request() will split the bio.
2568          */
2569         remaining2 = PAGE_SIZE - bmd->bi_size;
2570         remaining = max(remaining, remaining2);
2571
2572         BUG_ON(remaining < 0);
2573         return remaining;
2574 }
2575
2576 static void pkt_init_queue(struct pktcdvd_device *pd)
2577 {
2578         struct request_queue *q = pd->disk->queue;
2579
2580         blk_queue_make_request(q, pkt_make_request);
2581         blk_queue_logical_block_size(q, CD_FRAMESIZE);
2582         blk_queue_max_hw_sectors(q, PACKET_MAX_SECTORS);
2583         blk_queue_merge_bvec(q, pkt_merge_bvec);
2584         q->queuedata = pd;
2585 }
2586
2587 static int pkt_seq_show(struct seq_file *m, void *p)
2588 {
2589         struct pktcdvd_device *pd = m->private;
2590         char *msg;
2591         char bdev_buf[BDEVNAME_SIZE];
2592         int states[PACKET_NUM_STATES];
2593
2594         seq_printf(m, "Writer %s mapped to %s:\n", pd->name,
2595                    bdevname(pd->bdev, bdev_buf));
2596
2597         seq_printf(m, "\nSettings:\n");
2598         seq_printf(m, "\tpacket size:\t\t%dkB\n", pd->settings.size / 2);
2599
2600         if (pd->settings.write_type == 0)
2601                 msg = "Packet";
2602         else
2603                 msg = "Unknown";
2604         seq_printf(m, "\twrite type:\t\t%s\n", msg);
2605
2606         seq_printf(m, "\tpacket type:\t\t%s\n", pd->settings.fp ? "Fixed" : "Variable");
2607         seq_printf(m, "\tlink loss:\t\t%d\n", pd->settings.link_loss);
2608
2609         seq_printf(m, "\ttrack mode:\t\t%d\n", pd->settings.track_mode);
2610
2611         if (pd->settings.block_mode == PACKET_BLOCK_MODE1)
2612                 msg = "Mode 1";
2613         else if (pd->settings.block_mode == PACKET_BLOCK_MODE2)
2614                 msg = "Mode 2";
2615         else
2616                 msg = "Unknown";
2617         seq_printf(m, "\tblock mode:\t\t%s\n", msg);
2618
2619         seq_printf(m, "\nStatistics:\n");
2620         seq_printf(m, "\tpackets started:\t%lu\n", pd->stats.pkt_started);
2621         seq_printf(m, "\tpackets ended:\t\t%lu\n", pd->stats.pkt_ended);
2622         seq_printf(m, "\twritten:\t\t%lukB\n", pd->stats.secs_w >> 1);
2623         seq_printf(m, "\tread gather:\t\t%lukB\n", pd->stats.secs_rg >> 1);
2624         seq_printf(m, "\tread:\t\t\t%lukB\n", pd->stats.secs_r >> 1);
2625
2626         seq_printf(m, "\nMisc:\n");
2627         seq_printf(m, "\treference count:\t%d\n", pd->refcnt);
2628         seq_printf(m, "\tflags:\t\t\t0x%lx\n", pd->flags);
2629         seq_printf(m, "\tread speed:\t\t%ukB/s\n", pd->read_speed);
2630         seq_printf(m, "\twrite speed:\t\t%ukB/s\n", pd->write_speed);
2631         seq_printf(m, "\tstart offset:\t\t%lu\n", pd->offset);
2632         seq_printf(m, "\tmode page offset:\t%u\n", pd->mode_offset);
2633
2634         seq_printf(m, "\nQueue state:\n");
2635         seq_printf(m, "\tbios queued:\t\t%d\n", pd->bio_queue_size);
2636         seq_printf(m, "\tbios pending:\t\t%d\n", atomic_read(&pd->cdrw.pending_bios));
2637         seq_printf(m, "\tcurrent sector:\t\t0x%llx\n", (unsigned long long)pd->current_sector);
2638
2639         pkt_count_states(pd, states);
2640         seq_printf(m, "\tstate:\t\t\ti:%d ow:%d rw:%d ww:%d rec:%d fin:%d\n",
2641                    states[0], states[1], states[2], states[3], states[4], states[5]);
2642
2643         seq_printf(m, "\twrite congestion marks:\toff=%d on=%d\n",
2644                         pd->write_congestion_off,
2645                         pd->write_congestion_on);
2646         return 0;
2647 }
2648
2649 static int pkt_seq_open(struct inode *inode, struct file *file)
2650 {
2651         return single_open(file, pkt_seq_show, PDE(inode)->data);
2652 }
2653
2654 static const struct file_operations pkt_proc_fops = {
2655         .open   = pkt_seq_open,
2656         .read   = seq_read,
2657         .llseek = seq_lseek,
2658         .release = single_release
2659 };
2660
2661 static int pkt_new_dev(struct pktcdvd_device *pd, dev_t dev)
2662 {
2663         int i;
2664         int ret = 0;
2665         char b[BDEVNAME_SIZE];
2666         struct block_device *bdev;
2667
2668         if (pd->pkt_dev == dev) {
2669                 printk(DRIVER_NAME": Recursive setup not allowed\n");
2670                 return -EBUSY;
2671         }
2672         for (i = 0; i < MAX_WRITERS; i++) {
2673                 struct pktcdvd_device *pd2 = pkt_devs[i];
2674                 if (!pd2)
2675                         continue;
2676                 if (pd2->bdev->bd_dev == dev) {
2677                         printk(DRIVER_NAME": %s already setup\n", bdevname(pd2->bdev, b));
2678                         return -EBUSY;
2679                 }
2680                 if (pd2->pkt_dev == dev) {
2681                         printk(DRIVER_NAME": Can't chain pktcdvd devices\n");
2682                         return -EBUSY;
2683                 }
2684         }
2685
2686         bdev = bdget(dev);
2687         if (!bdev)
2688                 return -ENOMEM;
2689         ret = blkdev_get(bdev, FMODE_READ | FMODE_NDELAY, NULL);
2690         if (ret)
2691                 return ret;
2692
2693         /* This is safe, since we have a reference from open(). */
2694         __module_get(THIS_MODULE);
2695
2696         pd->bdev = bdev;
2697         set_blocksize(bdev, CD_FRAMESIZE);
2698
2699         pkt_init_queue(pd);
2700
2701         atomic_set(&pd->cdrw.pending_bios, 0);
2702         pd->cdrw.thread = kthread_run(kcdrwd, pd, "%s", pd->name);
2703         if (IS_ERR(pd->cdrw.thread)) {
2704                 printk(DRIVER_NAME": can't start kernel thread\n");
2705                 ret = -ENOMEM;
2706                 goto out_mem;
2707         }
2708
2709         proc_create_data(pd->name, 0, pkt_proc, &pkt_proc_fops, pd);
2710         DPRINTK(DRIVER_NAME": writer %s mapped to %s\n", pd->name, bdevname(bdev, b));
2711         return 0;
2712
2713 out_mem:
2714         blkdev_put(bdev, FMODE_READ | FMODE_NDELAY);
2715         /* This is safe: open() is still holding a reference. */
2716         module_put(THIS_MODULE);
2717         return ret;
2718 }
2719
2720 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
2721 {
2722         struct pktcdvd_device *pd = bdev->bd_disk->private_data;
2723         int ret;
2724
2725         VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
2726                 MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
2727
2728         mutex_lock(&pktcdvd_mutex);
2729         switch (cmd) {
2730         case CDROMEJECT:
2731                 /*
2732                  * The door gets locked when the device is opened, so we
2733                  * have to unlock it or else the eject command fails.
2734                  */
2735                 if (pd->refcnt == 1)
2736                         pkt_lock_door(pd, 0);
2737                 /* fallthru */
2738         /*
2739          * forward selected CDROM ioctls to CD-ROM, for UDF
2740          */
2741         case CDROMMULTISESSION:
2742         case CDROMREADTOCENTRY:
2743         case CDROM_LAST_WRITTEN:
2744         case CDROM_SEND_PACKET:
2745         case SCSI_IOCTL_SEND_COMMAND:
2746                 ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
2747                 break;
2748
2749         default:
2750                 VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
2751                 ret = -ENOTTY;
2752         }
2753         mutex_unlock(&pktcdvd_mutex);
2754
2755         return ret;
2756 }
2757
2758 static unsigned int pkt_check_events(struct gendisk *disk,
2759                                      unsigned int clearing)
2760 {
2761         struct pktcdvd_device *pd = disk->private_data;
2762         struct gendisk *attached_disk;
2763
2764         if (!pd)
2765                 return 0;
2766         if (!pd->bdev)
2767                 return 0;
2768         attached_disk = pd->bdev->bd_disk;
2769         if (!attached_disk || !attached_disk->fops->check_events)
2770                 return 0;
2771         return attached_disk->fops->check_events(attached_disk, clearing);
2772 }
2773
2774 static const struct block_device_operations pktcdvd_ops = {
2775         .owner =                THIS_MODULE,
2776         .open =                 pkt_open,
2777         .release =              pkt_close,
2778         .ioctl =                pkt_ioctl,
2779         .check_events =         pkt_check_events,
2780 };
2781
2782 static char *pktcdvd_devnode(struct gendisk *gd, umode_t *mode)
2783 {
2784         return kasprintf(GFP_KERNEL, "pktcdvd/%s", gd->disk_name);
2785 }
2786
2787 /*
2788  * Set up mapping from pktcdvd device to CD-ROM device.
2789  */
2790 static int pkt_setup_dev(dev_t dev, dev_t* pkt_dev)
2791 {
2792         int idx;
2793         int ret = -ENOMEM;
2794         struct pktcdvd_device *pd;
2795         struct gendisk *disk;
2796
2797         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2798
2799         for (idx = 0; idx < MAX_WRITERS; idx++)
2800                 if (!pkt_devs[idx])
2801                         break;
2802         if (idx == MAX_WRITERS) {
2803                 printk(DRIVER_NAME": max %d writers supported\n", MAX_WRITERS);
2804                 ret = -EBUSY;
2805                 goto out_mutex;
2806         }
2807
2808         pd = kzalloc(sizeof(struct pktcdvd_device), GFP_KERNEL);
2809         if (!pd)
2810                 goto out_mutex;
2811
2812         pd->rb_pool = mempool_create_kmalloc_pool(PKT_RB_POOL_SIZE,
2813                                                   sizeof(struct pkt_rb_node));
2814         if (!pd->rb_pool)
2815                 goto out_mem;
2816
2817         INIT_LIST_HEAD(&pd->cdrw.pkt_free_list);
2818         INIT_LIST_HEAD(&pd->cdrw.pkt_active_list);
2819         spin_lock_init(&pd->cdrw.active_list_lock);
2820
2821         spin_lock_init(&pd->lock);
2822         spin_lock_init(&pd->iosched.lock);
2823         bio_list_init(&pd->iosched.read_queue);
2824         bio_list_init(&pd->iosched.write_queue);
2825         sprintf(pd->name, DRIVER_NAME"%d", idx);
2826         init_waitqueue_head(&pd->wqueue);
2827         pd->bio_queue = RB_ROOT;
2828
2829         pd->write_congestion_on  = write_congestion_on;
2830         pd->write_congestion_off = write_congestion_off;
2831
2832         disk = alloc_disk(1);
2833         if (!disk)
2834                 goto out_mem;
2835         pd->disk = disk;
2836         disk->major = pktdev_major;
2837         disk->first_minor = idx;
2838         disk->fops = &pktcdvd_ops;
2839         disk->flags = GENHD_FL_REMOVABLE;
2840         strcpy(disk->disk_name, pd->name);
2841         disk->devnode = pktcdvd_devnode;
2842         disk->private_data = pd;
2843         disk->queue = blk_alloc_queue(GFP_KERNEL);
2844         if (!disk->queue)
2845                 goto out_mem2;
2846
2847         pd->pkt_dev = MKDEV(pktdev_major, idx);
2848         ret = pkt_new_dev(pd, dev);
2849         if (ret)
2850                 goto out_new_dev;
2851
2852         /* inherit events of the host device */
2853         disk->events = pd->bdev->bd_disk->events;
2854         disk->async_events = pd->bdev->bd_disk->async_events;
2855
2856         add_disk(disk);
2857
2858         pkt_sysfs_dev_new(pd);
2859         pkt_debugfs_dev_new(pd);
2860
2861         pkt_devs[idx] = pd;
2862         if (pkt_dev)
2863                 *pkt_dev = pd->pkt_dev;
2864
2865         mutex_unlock(&ctl_mutex);
2866         return 0;
2867
2868 out_new_dev:
2869         blk_cleanup_queue(disk->queue);
2870 out_mem2:
2871         put_disk(disk);
2872 out_mem:
2873         if (pd->rb_pool)
2874                 mempool_destroy(pd->rb_pool);
2875         kfree(pd);
2876 out_mutex:
2877         mutex_unlock(&ctl_mutex);
2878         printk(DRIVER_NAME": setup of pktcdvd device failed\n");
2879         return ret;
2880 }
2881
2882 /*
2883  * Tear down mapping from pktcdvd device to CD-ROM device.
2884  */
2885 static int pkt_remove_dev(dev_t pkt_dev)
2886 {
2887         struct pktcdvd_device *pd;
2888         int idx;
2889         int ret = 0;
2890
2891         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2892
2893         for (idx = 0; idx < MAX_WRITERS; idx++) {
2894                 pd = pkt_devs[idx];
2895                 if (pd && (pd->pkt_dev == pkt_dev))
2896                         break;
2897         }
2898         if (idx == MAX_WRITERS) {
2899                 DPRINTK(DRIVER_NAME": dev not setup\n");
2900                 ret = -ENXIO;
2901                 goto out;
2902         }
2903
2904         if (pd->refcnt > 0) {
2905                 ret = -EBUSY;
2906                 goto out;
2907         }
2908         if (!IS_ERR(pd->cdrw.thread))
2909                 kthread_stop(pd->cdrw.thread);
2910
2911         pkt_devs[idx] = NULL;
2912
2913         pkt_debugfs_dev_remove(pd);
2914         pkt_sysfs_dev_remove(pd);
2915
2916         blkdev_put(pd->bdev, FMODE_READ | FMODE_NDELAY);
2917
2918         remove_proc_entry(pd->name, pkt_proc);
2919         DPRINTK(DRIVER_NAME": writer %s unmapped\n", pd->name);
2920
2921         del_gendisk(pd->disk);
2922         blk_cleanup_queue(pd->disk->queue);
2923         put_disk(pd->disk);
2924
2925         mempool_destroy(pd->rb_pool);
2926         kfree(pd);
2927
2928         /* This is safe: open() is still holding a reference. */
2929         module_put(THIS_MODULE);
2930
2931 out:
2932         mutex_unlock(&ctl_mutex);
2933         return ret;
2934 }
2935
2936 static void pkt_get_status(struct pkt_ctrl_command *ctrl_cmd)
2937 {
2938         struct pktcdvd_device *pd;
2939
2940         mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
2941
2942         pd = pkt_find_dev_from_minor(ctrl_cmd->dev_index);
2943         if (pd) {
2944                 ctrl_cmd->dev = new_encode_dev(pd->bdev->bd_dev);
2945                 ctrl_cmd->pkt_dev = new_encode_dev(pd->pkt_dev);
2946         } else {
2947                 ctrl_cmd->dev = 0;
2948                 ctrl_cmd->pkt_dev = 0;
2949         }
2950         ctrl_cmd->num_devices = MAX_WRITERS;
2951
2952         mutex_unlock(&ctl_mutex);
2953 }
2954
2955 static long pkt_ctl_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2956 {
2957         void __user *argp = (void __user *)arg;
2958         struct pkt_ctrl_command ctrl_cmd;
2959         int ret = 0;
2960         dev_t pkt_dev = 0;
2961
2962         if (cmd != PACKET_CTRL_CMD)
2963                 return -ENOTTY;
2964
2965         if (copy_from_user(&ctrl_cmd, argp, sizeof(struct pkt_ctrl_command)))
2966                 return -EFAULT;
2967
2968         switch (ctrl_cmd.command) {
2969         case PKT_CTRL_CMD_SETUP:
2970                 if (!capable(CAP_SYS_ADMIN))
2971                         return -EPERM;
2972                 ret = pkt_setup_dev(new_decode_dev(ctrl_cmd.dev), &pkt_dev);
2973                 ctrl_cmd.pkt_dev = new_encode_dev(pkt_dev);
2974                 break;
2975         case PKT_CTRL_CMD_TEARDOWN:
2976                 if (!capable(CAP_SYS_ADMIN))
2977                         return -EPERM;
2978                 ret = pkt_remove_dev(new_decode_dev(ctrl_cmd.pkt_dev));
2979                 break;
2980         case PKT_CTRL_CMD_STATUS:
2981                 pkt_get_status(&ctrl_cmd);
2982                 break;
2983         default:
2984                 return -ENOTTY;
2985         }
2986
2987         if (copy_to_user(argp, &ctrl_cmd, sizeof(struct pkt_ctrl_command)))
2988                 return -EFAULT;
2989         return ret;
2990 }
2991
2992 #ifdef CONFIG_COMPAT
2993 static long pkt_ctl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
2994 {
2995         return pkt_ctl_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
2996 }
2997 #endif
2998
2999 static const struct file_operations pkt_ctl_fops = {
3000         .open           = nonseekable_open,
3001         .unlocked_ioctl = pkt_ctl_ioctl,
3002 #ifdef CONFIG_COMPAT
3003         .compat_ioctl   = pkt_ctl_compat_ioctl,
3004 #endif
3005         .owner          = THIS_MODULE,
3006         .llseek         = no_llseek,
3007 };
3008
3009 static struct miscdevice pkt_misc = {
3010         .minor          = MISC_DYNAMIC_MINOR,
3011         .name           = DRIVER_NAME,
3012         .nodename       = "pktcdvd/control",
3013         .fops           = &pkt_ctl_fops
3014 };
3015
3016 static int __init pkt_init(void)
3017 {
3018         int ret;
3019
3020         mutex_init(&ctl_mutex);
3021
3022         psd_pool = mempool_create_kmalloc_pool(PSD_POOL_SIZE,
3023                                         sizeof(struct packet_stacked_data));
3024         if (!psd_pool)
3025                 return -ENOMEM;
3026
3027         ret = register_blkdev(pktdev_major, DRIVER_NAME);
3028         if (ret < 0) {
3029                 printk(DRIVER_NAME": Unable to register block device\n");
3030                 goto out2;
3031         }
3032         if (!pktdev_major)
3033                 pktdev_major = ret;
3034
3035         ret = pkt_sysfs_init();
3036         if (ret)
3037                 goto out;
3038
3039         pkt_debugfs_init();
3040
3041         ret = misc_register(&pkt_misc);
3042         if (ret) {
3043                 printk(DRIVER_NAME": Unable to register misc device\n");
3044                 goto out_misc;
3045         }
3046
3047         pkt_proc = proc_mkdir("driver/"DRIVER_NAME, NULL);
3048
3049         return 0;
3050
3051 out_misc:
3052         pkt_debugfs_cleanup();
3053         pkt_sysfs_cleanup();
3054 out:
3055         unregister_blkdev(pktdev_major, DRIVER_NAME);
3056 out2:
3057         mempool_destroy(psd_pool);
3058         return ret;
3059 }
3060
3061 static void __exit pkt_exit(void)
3062 {
3063         remove_proc_entry("driver/"DRIVER_NAME, NULL);
3064         misc_deregister(&pkt_misc);
3065
3066         pkt_debugfs_cleanup();
3067         pkt_sysfs_cleanup();
3068
3069         unregister_blkdev(pktdev_major, DRIVER_NAME);
3070         mempool_destroy(psd_pool);
3071 }
3072
3073 MODULE_DESCRIPTION("Packet writing layer for CD/DVD drives");
3074 MODULE_AUTHOR("Jens Axboe <axboe@suse.de>");
3075 MODULE_LICENSE("GPL");
3076
3077 module_init(pkt_init);
3078 module_exit(pkt_exit);