drivers/block/pktcdvd.c

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