SAFE public projects git trees. - safe/jmp/linux-2.6/blob - drivers/ide/ide-tape.c

   1 /*
   2  * IDE ATAPI streaming tape driver.
   3  *
   4  * Copyright (C) 1995-1999  Gadi Oxman <gadio@netvision.net.il>
   5  * Copyright (C) 2003-2005  Bartlomiej Zolnierkiewicz
   6  *
   7  * This driver was constructed as a student project in the software laboratory
   8  * of the faculty of electrical engineering in the Technion - Israel's
   9  * Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David.
  10  *
  11  * It is hereby placed under the terms of the GNU general public license.
  12  * (See linux/COPYING).
  13  *
  14  * For a historical changelog see
  15  * Documentation/ide/ChangeLog.ide-tape.1995-2002
  16  */
  17
  18 #define DRV_NAME "ide-tape"
  19
  20 #define IDETAPE_VERSION "1.20"
  21
  22 #include <linux/module.h>
  23 #include <linux/types.h>
  24 #include <linux/string.h>
  25 #include <linux/kernel.h>
  26 #include <linux/delay.h>
  27 #include <linux/timer.h>
  28 #include <linux/mm.h>
  29 #include <linux/interrupt.h>
  30 #include <linux/jiffies.h>
  31 #include <linux/major.h>
  32 #include <linux/errno.h>
  33 #include <linux/genhd.h>
  34 #include <linux/seq_file.h>
  35 #include <linux/slab.h>
  36 #include <linux/pci.h>
  37 #include <linux/ide.h>
  38 #include <linux/smp_lock.h>
  39 #include <linux/completion.h>
  40 #include <linux/bitops.h>
  41 #include <linux/mutex.h>
  42 #include <scsi/scsi.h>
  43
  44 #include <asm/byteorder.h>
  45 #include <linux/irq.h>
  46 #include <linux/uaccess.h>
  47 #include <linux/io.h>
  48 #include <asm/unaligned.h>
  49 #include <linux/mtio.h>
  50
  51 /* define to see debug info */
  52 #undef IDETAPE_DEBUG_LOG
  53
  54 #ifdef IDETAPE_DEBUG_LOG
  55 #define ide_debug_log(lvl, fmt, args...) __ide_debug_log(lvl, fmt, ## args)
  56 #else
  57 #define ide_debug_log(lvl, fmt, args...) do {} while (0)
  58 #endif
  59
  60 /**************************** Tunable parameters *****************************/
  61 /*
  62  * After each failed packet command we issue a request sense command and retry
  63  * the packet command IDETAPE_MAX_PC_RETRIES times.
  64  *
  65  * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
  66  */
  67 #define IDETAPE_MAX_PC_RETRIES          3
  68
  69 /*
  70  * The following parameter is used to select the point in the internal tape fifo
  71  * in which we will start to refill the buffer. Decreasing the following
  72  * parameter will improve the system's latency and interactive response, while
  73  * using a high value might improve system throughput.
  74  */
  75 #define IDETAPE_FIFO_THRESHOLD          2
  76
  77 /*
  78  * DSC polling parameters.
  79  *
  80  * Polling for DSC (a single bit in the status register) is a very important
  81  * function in ide-tape. There are two cases in which we poll for DSC:
  82  *
  83  * 1. Before a read/write packet command, to ensure that we can transfer data
  84  * from/to the tape's data buffers, without causing an actual media access.
  85  * In case the tape is not ready yet, we take out our request from the device
  86  * request queue, so that ide.c could service requests from the other device
  87  * on the same interface in the meantime.
  88  *
  89  * 2. After the successful initialization of a "media access packet command",
  90  * which is a command that can take a long time to complete (the interval can
  91  * range from several seconds to even an hour). Again, we postpone our request
  92  * in the middle to free the bus for the other device. The polling frequency
  93  * here should be lower than the read/write frequency since those media access
  94  * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
  95  * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
  96  * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
  97  *
  98  * We also set a timeout for the timer, in case something goes wrong. The
  99  * timeout should be longer then the maximum execution time of a tape operation.
 100  */
 101
 102 /* DSC timings. */
 103 #define IDETAPE_DSC_RW_MIN              5*HZ/100        /* 50 msec */
 104 #define IDETAPE_DSC_RW_MAX              40*HZ/100       /* 400 msec */
 105 #define IDETAPE_DSC_RW_TIMEOUT          2*60*HZ         /* 2 minutes */
 106 #define IDETAPE_DSC_MA_FAST             2*HZ            /* 2 seconds */
 107 #define IDETAPE_DSC_MA_THRESHOLD        5*60*HZ         /* 5 minutes */
 108 #define IDETAPE_DSC_MA_SLOW             30*HZ           /* 30 seconds */
 109 #define IDETAPE_DSC_MA_TIMEOUT          2*60*60*HZ      /* 2 hours */
 110
 111 /*************************** End of tunable parameters ***********************/
 112
 113 /* tape directions */
 114 enum {
 115         IDETAPE_DIR_NONE  = (1 << 0),
 116         IDETAPE_DIR_READ  = (1 << 1),
 117         IDETAPE_DIR_WRITE = (1 << 2),
 118 };
 119
 120 /* Tape door status */
 121 #define DOOR_UNLOCKED                   0
 122 #define DOOR_LOCKED                     1
 123 #define DOOR_EXPLICITLY_LOCKED          2
 124
 125 /* Some defines for the SPACE command */
 126 #define IDETAPE_SPACE_OVER_FILEMARK     1
 127 #define IDETAPE_SPACE_TO_EOD            3
 128
 129 /* Some defines for the LOAD UNLOAD command */
 130 #define IDETAPE_LU_LOAD_MASK            1
 131 #define IDETAPE_LU_RETENSION_MASK       2
 132 #define IDETAPE_LU_EOT_MASK             4
 133
 134 /* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
 135 #define IDETAPE_BLOCK_DESCRIPTOR        0
 136 #define IDETAPE_CAPABILITIES_PAGE       0x2a
 137
 138 /*
 139  * Most of our global data which we need to save even as we leave the driver due
 140  * to an interrupt or a timer event is stored in the struct defined below.
 141  */
 142 typedef struct ide_tape_obj {
 143         ide_drive_t             *drive;
 144         struct ide_driver       *driver;
 145         struct gendisk          *disk;
 146         struct device           dev;
 147
 148         /* used by REQ_IDETAPE_{READ,WRITE} requests */
 149         struct ide_atapi_pc queued_pc;
 150
 151         /*
 152          * DSC polling variables.
 153          *
 154          * While polling for DSC we use postponed_rq to postpone the current
 155          * request so that ide.c will be able to service pending requests on the
 156          * other device. Note that at most we will have only one DSC (usually
 157          * data transfer) request in the device request queue.
 158          */
 159         bool postponed_rq;
 160
 161         /* The time in which we started polling for DSC */
 162         unsigned long dsc_polling_start;
 163         /* Timer used to poll for dsc */
 164         struct timer_list dsc_timer;
 165         /* Read/Write dsc polling frequency */
 166         unsigned long best_dsc_rw_freq;
 167         unsigned long dsc_poll_freq;
 168         unsigned long dsc_timeout;
 169
 170         /* Read position information */
 171         u8 partition;
 172         /* Current block */
 173         unsigned int first_frame;
 174
 175         /* Last error information */
 176         u8 sense_key, asc, ascq;
 177
 178         /* Character device operation */
 179         unsigned int minor;
 180         /* device name */
 181         char name[4];
 182         /* Current character device data transfer direction */
 183         u8 chrdev_dir;
 184
 185         /* tape block size, usually 512 or 1024 bytes */
 186         unsigned short blk_size;
 187         int user_bs_factor;
 188
 189         /* Copy of the tape's Capabilities and Mechanical Page */
 190         u8 caps[20];
 191
 192         /*
 193          * Active data transfer request parameters.
 194          *
 195          * At most, there is only one ide-tape originated data transfer request
 196          * in the device request queue. This allows ide.c to easily service
 197          * requests from the other device when we postpone our active request.
 198          */
 199
 200         /* Data buffer size chosen based on the tape's recommendation */
 201         int buffer_size;
 202         /* Staging buffer of buffer_size bytes */
 203         void *buf;
 204         /* The read/write cursor */
 205         void *cur;
 206         /* The number of valid bytes in buf */
 207         size_t valid;
 208
 209         /* Measures average tape speed */
 210         unsigned long avg_time;
 211         int avg_size;
 212         int avg_speed;
 213
 214         /* the door is currently locked */
 215         int door_locked;
 216         /* the tape hardware is write protected */
 217         char drv_write_prot;
 218         /* the tape is write protected (hardware or opened as read-only) */
 219         char write_prot;
 220 } idetape_tape_t;
 221
 222 static DEFINE_MUTEX(idetape_ref_mutex);
 223
 224 static struct class *idetape_sysfs_class;
 225
 226 static void ide_tape_release(struct device *);
 227
 228 static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
 229
 230 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk, bool cdev,
 231                                          unsigned int i)
 232 {
 233         struct ide_tape_obj *tape = NULL;
 234
 235         mutex_lock(&idetape_ref_mutex);
 236
 237         if (cdev)
 238                 tape = idetape_devs[i];
 239         else
 240                 tape = ide_drv_g(disk, ide_tape_obj);
 241
 242         if (tape) {
 243                 if (ide_device_get(tape->drive))
 244                         tape = NULL;
 245                 else
 246                         get_device(&tape->dev);
 247         }
 248
 249         mutex_unlock(&idetape_ref_mutex);
 250         return tape;
 251 }
 252
 253 static void ide_tape_put(struct ide_tape_obj *tape)
 254 {
 255         ide_drive_t *drive = tape->drive;
 256
 257         mutex_lock(&idetape_ref_mutex);
 258         put_device(&tape->dev);
 259         ide_device_put(drive);
 260         mutex_unlock(&idetape_ref_mutex);
 261 }
 262
 263 /*
 264  * called on each failed packet command retry to analyze the request sense. We
 265  * currently do not utilize this information.
 266  */
 267 static void idetape_analyze_error(ide_drive_t *drive)
 268 {
 269         idetape_tape_t *tape = drive->driver_data;
 270         struct ide_atapi_pc *pc = drive->failed_pc;
 271         struct request *rq = drive->hwif->rq;
 272         u8 *sense = bio_data(rq->bio);
 273
 274         tape->sense_key = sense[2] & 0xF;
 275         tape->asc       = sense[12];
 276         tape->ascq      = sense[13];
 277
 278         ide_debug_log(IDE_DBG_FUNC,
 279                       "cmd: 0x%x, sense key = %x, asc = %x, ascq = %x",
 280                       rq->cmd[0], tape->sense_key, tape->asc, tape->ascq);
 281
 282         /* correct remaining bytes to transfer */
 283         if (pc->flags & PC_FLAG_DMA_ERROR)
 284                 rq->resid_len = tape->blk_size * get_unaligned_be32(&sense[3]);
 285
 286         /*
 287          * If error was the result of a zero-length read or write command,
 288          * with sense key=5, asc=0x22, ascq=0, let it slide.  Some drives
 289          * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
 290          */
 291         if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
 292             /* length == 0 */
 293             && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
 294                 if (tape->sense_key == 5) {
 295                         /* don't report an error, everything's ok */
 296                         pc->error = 0;
 297                         /* don't retry read/write */
 298                         pc->flags |= PC_FLAG_ABORT;
 299                 }
 300         }
 301         if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
 302                 pc->error = IDE_DRV_ERROR_FILEMARK;
 303                 pc->flags |= PC_FLAG_ABORT;
 304         }
 305         if (pc->c[0] == WRITE_6) {
 306                 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
 307                      && tape->asc == 0x0 && tape->ascq == 0x2)) {
 308                         pc->error = IDE_DRV_ERROR_EOD;
 309                         pc->flags |= PC_FLAG_ABORT;
 310                 }
 311         }
 312         if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
 313                 if (tape->sense_key == 8) {
 314                         pc->error = IDE_DRV_ERROR_EOD;
 315                         pc->flags |= PC_FLAG_ABORT;
 316                 }
 317                 if (!(pc->flags & PC_FLAG_ABORT) &&
 318                     (blk_rq_bytes(rq) - rq->resid_len))
 319                         pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
 320         }
 321 }
 322
 323 static void ide_tape_handle_dsc(ide_drive_t *);
 324
 325 static int ide_tape_callback(ide_drive_t *drive, int dsc)
 326 {
 327         idetape_tape_t *tape = drive->driver_data;
 328         struct ide_atapi_pc *pc = drive->pc;
 329         struct request *rq = drive->hwif->rq;
 330         int uptodate = pc->error ? 0 : 1;
 331         int err = uptodate ? 0 : IDE_DRV_ERROR_GENERAL;
 332
 333         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc: %d, err: %d", rq->cmd[0],
 334                       dsc, err);
 335
 336         if (dsc)
 337                 ide_tape_handle_dsc(drive);
 338
 339         if (drive->failed_pc == pc)
 340                 drive->failed_pc = NULL;
 341
 342         if (pc->c[0] == REQUEST_SENSE) {
 343                 if (uptodate)
 344                         idetape_analyze_error(drive);
 345                 else
 346                         printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
 347                                         "itself - Aborting request!\n");
 348         } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
 349                 unsigned int blocks =
 350                         (blk_rq_bytes(rq) - rq->resid_len) / tape->blk_size;
 351
 352                 tape->avg_size += blocks * tape->blk_size;
 353
 354                 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
 355                         tape->avg_speed = tape->avg_size * HZ /
 356                                 (jiffies - tape->avg_time) / 1024;
 357                         tape->avg_size = 0;
 358                         tape->avg_time = jiffies;
 359                 }
 360
 361                 tape->first_frame += blocks;
 362
 363                 if (pc->error) {
 364                         uptodate = 0;
 365                         err = pc->error;
 366                 }
 367         }
 368         rq->errors = err;
 369
 370         return uptodate;
 371 }
 372
 373 /*
 374  * Postpone the current request so that ide.c will be able to service requests
 375  * from another device on the same port while we are polling for DSC.
 376  */
 377 static void ide_tape_stall_queue(ide_drive_t *drive)
 378 {
 379         idetape_tape_t *tape = drive->driver_data;
 380
 381         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, dsc_poll_freq: %lu",
 382                       drive->hwif->rq->cmd[0], tape->dsc_poll_freq);
 383
 384         tape->postponed_rq = true;
 385
 386         ide_stall_queue(drive, tape->dsc_poll_freq);
 387 }
 388
 389 static void ide_tape_handle_dsc(ide_drive_t *drive)
 390 {
 391         idetape_tape_t *tape = drive->driver_data;
 392
 393         /* Media access command */
 394         tape->dsc_polling_start = jiffies;
 395         tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
 396         tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
 397         /* Allow ide.c to handle other requests */
 398         ide_tape_stall_queue(drive);
 399 }
 400
 401 /*
 402  * Packet Command Interface
 403  *
 404  * The current Packet Command is available in drive->pc, and will not change
 405  * until we finish handling it. Each packet command is associated with a
 406  * callback function that will be called when the command is finished.
 407  *
 408  * The handling will be done in three stages:
 409  *
 410  * 1. ide_tape_issue_pc will send the packet command to the drive, and will set
 411  * the interrupt handler to ide_pc_intr.
 412  *
 413  * 2. On each interrupt, ide_pc_intr will be called. This step will be
 414  * repeated until the device signals us that no more interrupts will be issued.
 415  *
 416  * 3. ATAPI Tape media access commands have immediate status with a delayed
 417  * process. In case of a successful initiation of a media access packet command,
 418  * the DSC bit will be set when the actual execution of the command is finished.
 419  * Since the tape drive will not issue an interrupt, we have to poll for this
 420  * event. In this case, we define the request as "low priority request" by
 421  * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
 422  * exit the driver.
 423  *
 424  * ide.c will then give higher priority to requests which originate from the
 425  * other device, until will change rq_status to RQ_ACTIVE.
 426  *
 427  * 4. When the packet command is finished, it will be checked for errors.
 428  *
 429  * 5. In case an error was found, we queue a request sense packet command in
 430  * front of the request queue and retry the operation up to
 431  * IDETAPE_MAX_PC_RETRIES times.
 432  *
 433  * 6. In case no error was found, or we decided to give up and not to retry
 434  * again, the callback function will be called and then we will handle the next
 435  * request.
 436  */
 437
 438 static ide_startstop_t ide_tape_issue_pc(ide_drive_t *drive,
 439                                          struct ide_cmd *cmd,
 440                                          struct ide_atapi_pc *pc)
 441 {
 442         idetape_tape_t *tape = drive->driver_data;
 443         struct request *rq = drive->hwif->rq;
 444
 445         if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
 446                 drive->failed_pc = pc;
 447
 448         /* Set the current packet command */
 449         drive->pc = pc;
 450
 451         if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
 452                 (pc->flags & PC_FLAG_ABORT)) {
 453
 454                 /*
 455                  * We will "abort" retrying a packet command in case legitimate
 456                  * error code was received (crossing a filemark, or end of the
 457                  * media, for example).
 458                  */
 459                 if (!(pc->flags & PC_FLAG_ABORT)) {
 460                         if (!(pc->c[0] == TEST_UNIT_READY &&
 461                               tape->sense_key == 2 && tape->asc == 4 &&
 462                              (tape->ascq == 1 || tape->ascq == 8))) {
 463                                 printk(KERN_ERR "ide-tape: %s: I/O error, "
 464                                                 "pc = %2x, key = %2x, "
 465                                                 "asc = %2x, ascq = %2x\n",
 466                                                 tape->name, pc->c[0],
 467                                                 tape->sense_key, tape->asc,
 468                                                 tape->ascq);
 469                         }
 470                         /* Giving up */
 471                         pc->error = IDE_DRV_ERROR_GENERAL;
 472                 }
 473
 474                 drive->failed_pc = NULL;
 475                 drive->pc_callback(drive, 0);
 476                 ide_complete_rq(drive, -EIO, blk_rq_bytes(rq));
 477                 return ide_stopped;
 478         }
 479         ide_debug_log(IDE_DBG_SENSE, "retry #%d, cmd: 0x%02x", pc->retries,
 480                       pc->c[0]);
 481
 482         pc->retries++;
 483
 484         return ide_issue_pc(drive, cmd);
 485 }
 486
 487 /* A mode sense command is used to "sense" tape parameters. */
 488 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
 489 {
 490         ide_init_pc(pc);
 491         pc->c[0] = MODE_SENSE;
 492         if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
 493                 /* DBD = 1 - Don't return block descriptors */
 494                 pc->c[1] = 8;
 495         pc->c[2] = page_code;
 496         /*
 497          * Changed pc->c[3] to 0 (255 will at best return unused info).
 498          *
 499          * For SCSI this byte is defined as subpage instead of high byte
 500          * of length and some IDE drives seem to interpret it this way
 501          * and return an error when 255 is used.
 502          */
 503         pc->c[3] = 0;
 504         /* We will just discard data in that case */
 505         pc->c[4] = 255;
 506         if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
 507                 pc->req_xfer = 12;
 508         else if (page_code == IDETAPE_CAPABILITIES_PAGE)
 509                 pc->req_xfer = 24;
 510         else
 511                 pc->req_xfer = 50;
 512 }
 513
 514 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
 515 {
 516         ide_hwif_t *hwif = drive->hwif;
 517         idetape_tape_t *tape = drive->driver_data;
 518         struct ide_atapi_pc *pc = drive->pc;
 519         u8 stat;
 520
 521         stat = hwif->tp_ops->read_status(hwif);
 522
 523         if (stat & ATA_DSC) {
 524                 if (stat & ATA_ERR) {
 525                         /* Error detected */
 526                         if (pc->c[0] != TEST_UNIT_READY)
 527                                 printk(KERN_ERR "ide-tape: %s: I/O error, ",
 528                                                 tape->name);
 529                         /* Retry operation */
 530                         ide_retry_pc(drive);
 531                         return ide_stopped;
 532                 }
 533                 pc->error = 0;
 534         } else {
 535                 pc->error = IDE_DRV_ERROR_GENERAL;
 536                 drive->failed_pc = NULL;
 537         }
 538         drive->pc_callback(drive, 0);
 539         return ide_stopped;
 540 }
 541
 542 static void ide_tape_create_rw_cmd(idetape_tape_t *tape,
 543                                    struct ide_atapi_pc *pc, struct request *rq,
 544                                    u8 opcode)
 545 {
 546         unsigned int length = blk_rq_sectors(rq) / (tape->blk_size >> 9);
 547
 548         ide_init_pc(pc);
 549         put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
 550         pc->c[1] = 1;
 551
 552         if (blk_rq_bytes(rq) == tape->buffer_size)
 553                 pc->flags |= PC_FLAG_DMA_OK;
 554
 555         if (opcode == READ_6)
 556                 pc->c[0] = READ_6;
 557         else if (opcode == WRITE_6) {
 558                 pc->c[0] = WRITE_6;
 559                 pc->flags |= PC_FLAG_WRITING;
 560         }
 561
 562         memcpy(rq->cmd, pc->c, 12);
 563 }
 564
 565 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
 566                                           struct request *rq, sector_t block)
 567 {
 568         ide_hwif_t *hwif = drive->hwif;
 569         idetape_tape_t *tape = drive->driver_data;
 570         struct ide_atapi_pc *pc = NULL;
 571         struct ide_cmd cmd;
 572         u8 stat;
 573
 574         ide_debug_log(IDE_DBG_RQ, "cmd: 0x%x, sector: %llu, nr_sectors: %u",
 575                       rq->cmd[0], (unsigned long long)blk_rq_pos(rq),
 576                       blk_rq_sectors(rq));
 577
 578         BUG_ON(!(blk_special_request(rq) || blk_sense_request(rq)));
 579
 580         /* Retry a failed packet command */
 581         if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) {
 582                 pc = drive->failed_pc;
 583                 goto out;
 584         }
 585
 586         /*
 587          * If the tape is still busy, postpone our request and service
 588          * the other device meanwhile.
 589          */
 590         stat = hwif->tp_ops->read_status(hwif);
 591
 592         if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 &&
 593             (rq->cmd[13] & REQ_IDETAPE_PC2) == 0)
 594                 drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
 595
 596         if (drive->dev_flags & IDE_DFLAG_POST_RESET) {
 597                 drive->atapi_flags |= IDE_AFLAG_IGNORE_DSC;
 598                 drive->dev_flags &= ~IDE_DFLAG_POST_RESET;
 599         }
 600
 601         if (!(drive->atapi_flags & IDE_AFLAG_IGNORE_DSC) &&
 602             !(stat & ATA_DSC)) {
 603                 if (!tape->postponed_rq) {
 604                         tape->dsc_polling_start = jiffies;
 605                         tape->dsc_poll_freq = tape->best_dsc_rw_freq;
 606                         tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
 607                 } else if (time_after(jiffies, tape->dsc_timeout)) {
 608                         printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
 609                                 tape->name);
 610                         if (rq->cmd[13] & REQ_IDETAPE_PC2) {
 611                                 idetape_media_access_finished(drive);
 612                                 return ide_stopped;
 613                         } else {
 614                                 return ide_do_reset(drive);
 615                         }
 616                 } else if (time_after(jiffies,
 617                                         tape->dsc_polling_start +
 618                                         IDETAPE_DSC_MA_THRESHOLD))
 619                         tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
 620                 ide_tape_stall_queue(drive);
 621                 return ide_stopped;
 622         } else {
 623                 drive->atapi_flags &= ~IDE_AFLAG_IGNORE_DSC;
 624                 tape->postponed_rq = false;
 625         }
 626
 627         if (rq->cmd[13] & REQ_IDETAPE_READ) {
 628                 pc = &tape->queued_pc;
 629                 ide_tape_create_rw_cmd(tape, pc, rq, READ_6);
 630                 goto out;
 631         }
 632         if (rq->cmd[13] & REQ_IDETAPE_WRITE) {
 633                 pc = &tape->queued_pc;
 634                 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6);
 635                 goto out;
 636         }
 637         if (rq->cmd[13] & REQ_IDETAPE_PC1) {
 638                 pc = (struct ide_atapi_pc *)rq->special;
 639                 rq->cmd[13] &= ~(REQ_IDETAPE_PC1);
 640                 rq->cmd[13] |= REQ_IDETAPE_PC2;
 641                 goto out;
 642         }
 643         if (rq->cmd[13] & REQ_IDETAPE_PC2) {
 644                 idetape_media_access_finished(drive);
 645                 return ide_stopped;
 646         }
 647         BUG();
 648
 649 out:
 650         /* prepare sense request for this command */
 651         ide_prep_sense(drive, rq);
 652
 653         memset(&cmd, 0, sizeof(cmd));
 654
 655         if (rq_data_dir(rq))
 656                 cmd.tf_flags |= IDE_TFLAG_WRITE;
 657
 658         cmd.rq = rq;
 659
 660         ide_init_sg_cmd(&cmd, blk_rq_bytes(rq));
 661         ide_map_sg(drive, &cmd);
 662
 663         return ide_tape_issue_pc(drive, &cmd, pc);
 664 }
 665
 666 /*
 667  * Write a filemark if write_filemark=1. Flush the device buffers without
 668  * writing a filemark otherwise.
 669  */
 670 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
 671                 struct ide_atapi_pc *pc, int write_filemark)
 672 {
 673         ide_init_pc(pc);
 674         pc->c[0] = WRITE_FILEMARKS;
 675         pc->c[4] = write_filemark;
 676         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 677 }
 678
 679 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
 680 {
 681         idetape_tape_t *tape = drive->driver_data;
 682         struct gendisk *disk = tape->disk;
 683         int load_attempted = 0;
 684
 685         /* Wait for the tape to become ready */
 686         set_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT), &drive->atapi_flags);
 687         timeout += jiffies;
 688         while (time_before(jiffies, timeout)) {
 689                 if (ide_do_test_unit_ready(drive, disk) == 0)
 690                         return 0;
 691                 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
 692                     || (tape->asc == 0x3A)) {
 693                         /* no media */
 694                         if (load_attempted)
 695                                 return -ENOMEDIUM;
 696                         ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
 697                         load_attempted = 1;
 698                 /* not about to be ready */
 699                 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
 700                              (tape->ascq == 1 || tape->ascq == 8)))
 701                         return -EIO;
 702                 msleep(100);
 703         }
 704         return -EIO;
 705 }
 706
 707 static int idetape_flush_tape_buffers(ide_drive_t *drive)
 708 {
 709         struct ide_tape_obj *tape = drive->driver_data;
 710         struct ide_atapi_pc pc;
 711         int rc;
 712
 713         idetape_create_write_filemark_cmd(drive, &pc, 0);
 714         rc = ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0);
 715         if (rc)
 716                 return rc;
 717         idetape_wait_ready(drive, 60 * 5 * HZ);
 718         return 0;
 719 }
 720
 721 static int ide_tape_read_position(ide_drive_t *drive)
 722 {
 723         idetape_tape_t *tape = drive->driver_data;
 724         struct ide_atapi_pc pc;
 725         u8 buf[20];
 726
 727         ide_debug_log(IDE_DBG_FUNC, "enter");
 728
 729         /* prep cmd */
 730         ide_init_pc(&pc);
 731         pc.c[0] = READ_POSITION;
 732         pc.req_xfer = 20;
 733
 734         if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer))
 735                 return -1;
 736
 737         if (!pc.error) {
 738                 ide_debug_log(IDE_DBG_FUNC, "BOP - %s",
 739                                 (buf[0] & 0x80) ? "Yes" : "No");
 740                 ide_debug_log(IDE_DBG_FUNC, "EOP - %s",
 741                                 (buf[0] & 0x40) ? "Yes" : "No");
 742
 743                 if (buf[0] & 0x4) {
 744                         printk(KERN_INFO "ide-tape: Block location is unknown"
 745                                          "to the tape\n");
 746                         clear_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
 747                                   &drive->atapi_flags);
 748                         return -1;
 749                 } else {
 750                         ide_debug_log(IDE_DBG_FUNC, "Block Location: %u",
 751                                       be32_to_cpup((__be32 *)&buf[4]));
 752
 753                         tape->partition = buf[1];
 754                         tape->first_frame = be32_to_cpup((__be32 *)&buf[4]);
 755                         set_bit(ilog2(IDE_AFLAG_ADDRESS_VALID),
 756                                 &drive->atapi_flags);
 757                 }
 758         }
 759
 760         return tape->first_frame;
 761 }
 762
 763 static void idetape_create_locate_cmd(ide_drive_t *drive,
 764                 struct ide_atapi_pc *pc,
 765                 unsigned int block, u8 partition, int skip)
 766 {
 767         ide_init_pc(pc);
 768         pc->c[0] = POSITION_TO_ELEMENT;
 769         pc->c[1] = 2;
 770         put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
 771         pc->c[8] = partition;
 772         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 773 }
 774
 775 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
 776 {
 777         idetape_tape_t *tape = drive->driver_data;
 778
 779         if (tape->chrdev_dir != IDETAPE_DIR_READ)
 780                 return;
 781
 782         clear_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags);
 783         tape->valid = 0;
 784         if (tape->buf != NULL) {
 785                 kfree(tape->buf);
 786                 tape->buf = NULL;
 787         }
 788
 789         tape->chrdev_dir = IDETAPE_DIR_NONE;
 790 }
 791
 792 /*
 793  * Position the tape to the requested block using the LOCATE packet command.
 794  * A READ POSITION command is then issued to check where we are positioned. Like
 795  * all higher level operations, we queue the commands at the tail of the request
 796  * queue and wait for their completion.
 797  */
 798 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
 799                 u8 partition, int skip)
 800 {
 801         idetape_tape_t *tape = drive->driver_data;
 802         struct gendisk *disk = tape->disk;
 803         int ret;
 804         struct ide_atapi_pc pc;
 805
 806         if (tape->chrdev_dir == IDETAPE_DIR_READ)
 807                 __ide_tape_discard_merge_buffer(drive);
 808         idetape_wait_ready(drive, 60 * 5 * HZ);
 809         idetape_create_locate_cmd(drive, &pc, block, partition, skip);
 810         ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
 811         if (ret)
 812                 return ret;
 813
 814         ret = ide_tape_read_position(drive);
 815         if (ret < 0)
 816                 return ret;
 817         return 0;
 818 }
 819
 820 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
 821                                           int restore_position)
 822 {
 823         idetape_tape_t *tape = drive->driver_data;
 824         int seek, position;
 825
 826         __ide_tape_discard_merge_buffer(drive);
 827         if (restore_position) {
 828                 position = ide_tape_read_position(drive);
 829                 seek = position > 0 ? position : 0;
 830                 if (idetape_position_tape(drive, seek, 0, 0)) {
 831                         printk(KERN_INFO "ide-tape: %s: position_tape failed in"
 832                                          " %s\n", tape->name, __func__);
 833                         return;
 834                 }
 835         }
 836 }
 837
 838 /*
 839  * Generate a read/write request for the block device interface and wait for it
 840  * to be serviced.
 841  */
 842 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int size)
 843 {
 844         idetape_tape_t *tape = drive->driver_data;
 845         struct request *rq;
 846         int ret;
 847
 848         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x, size: %d", cmd, size);
 849
 850         BUG_ON(cmd != REQ_IDETAPE_READ && cmd != REQ_IDETAPE_WRITE);
 851         BUG_ON(size < 0 || size % tape->blk_size);
 852
 853         rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
 854         rq->cmd_type = REQ_TYPE_SPECIAL;
 855         rq->cmd[13] = cmd;
 856         rq->rq_disk = tape->disk;
 857         rq->__sector = tape->first_frame;
 858
 859         if (size) {
 860                 ret = blk_rq_map_kern(drive->queue, rq, tape->buf, size,
 861                                       __GFP_WAIT);
 862                 if (ret)
 863                         goto out_put;
 864         }
 865
 866         blk_execute_rq(drive->queue, tape->disk, rq, 0);
 867
 868         /* calculate the number of transferred bytes and update buffer state */
 869         size -= rq->resid_len;
 870         tape->cur = tape->buf;
 871         if (cmd == REQ_IDETAPE_READ)
 872                 tape->valid = size;
 873         else
 874                 tape->valid = 0;
 875
 876         ret = size;
 877         if (rq->errors == IDE_DRV_ERROR_GENERAL)
 878                 ret = -EIO;
 879 out_put:
 880         blk_put_request(rq);
 881         return ret;
 882 }
 883
 884 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
 885 {
 886         ide_init_pc(pc);
 887         pc->c[0] = INQUIRY;
 888         pc->c[4] = 254;
 889         pc->req_xfer = 254;
 890 }
 891
 892 static void idetape_create_rewind_cmd(ide_drive_t *drive,
 893                 struct ide_atapi_pc *pc)
 894 {
 895         ide_init_pc(pc);
 896         pc->c[0] = REZERO_UNIT;
 897         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 898 }
 899
 900 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
 901 {
 902         ide_init_pc(pc);
 903         pc->c[0] = ERASE;
 904         pc->c[1] = 1;
 905         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 906 }
 907
 908 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
 909 {
 910         ide_init_pc(pc);
 911         pc->c[0] = SPACE;
 912         put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
 913         pc->c[1] = cmd;
 914         pc->flags |= PC_FLAG_WAIT_FOR_DSC;
 915 }
 916
 917 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
 918 {
 919         idetape_tape_t *tape = drive->driver_data;
 920
 921         if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
 922                 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
 923                                 " but we are not writing.\n");
 924                 return;
 925         }
 926         if (tape->buf) {
 927                 size_t aligned = roundup(tape->valid, tape->blk_size);
 928
 929                 memset(tape->cur, 0, aligned - tape->valid);
 930                 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, aligned);
 931                 kfree(tape->buf);
 932                 tape->buf = NULL;
 933         }
 934         tape->chrdev_dir = IDETAPE_DIR_NONE;
 935 }
 936
 937 static int idetape_init_rw(ide_drive_t *drive, int dir)
 938 {
 939         idetape_tape_t *tape = drive->driver_data;
 940         int rc;
 941
 942         BUG_ON(dir != IDETAPE_DIR_READ && dir != IDETAPE_DIR_WRITE);
 943
 944         if (tape->chrdev_dir == dir)
 945                 return 0;
 946
 947         if (tape->chrdev_dir == IDETAPE_DIR_READ)
 948                 ide_tape_discard_merge_buffer(drive, 1);
 949         else if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
 950                 ide_tape_flush_merge_buffer(drive);
 951                 idetape_flush_tape_buffers(drive);
 952         }
 953
 954         if (tape->buf || tape->valid) {
 955                 printk(KERN_ERR "ide-tape: valid should be 0 now\n");
 956                 tape->valid = 0;
 957         }
 958
 959         tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
 960         if (!tape->buf)
 961                 return -ENOMEM;
 962         tape->chrdev_dir = dir;
 963         tape->cur = tape->buf;
 964
 965         /*
 966          * Issue a 0 rw command to ensure that DSC handshake is
 967          * switched from completion mode to buffer available mode.  No
 968          * point in issuing this if DSC overlap isn't supported, some
 969          * drives (Seagate STT3401A) will return an error.
 970          */
 971         if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) {
 972                 int cmd = dir == IDETAPE_DIR_READ ? REQ_IDETAPE_READ
 973                                                   : REQ_IDETAPE_WRITE;
 974
 975                 rc = idetape_queue_rw_tail(drive, cmd, 0);
 976                 if (rc < 0) {
 977                         kfree(tape->buf);
 978                         tape->buf = NULL;
 979                         tape->chrdev_dir = IDETAPE_DIR_NONE;
 980                         return rc;
 981                 }
 982         }
 983
 984         return 0;
 985 }
 986
 987 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
 988 {
 989         idetape_tape_t *tape = drive->driver_data;
 990
 991         memset(tape->buf, 0, tape->buffer_size);
 992
 993         while (bcount) {
 994                 unsigned int count = min(tape->buffer_size, bcount);
 995
 996                 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, count);
 997                 bcount -= count;
 998         }
 999 }
1000
1001 /*
1002  * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1003  * currently support only one partition.
1004  */
1005 static int idetape_rewind_tape(ide_drive_t *drive)
1006 {
1007         struct ide_tape_obj *tape = drive->driver_data;
1008         struct gendisk *disk = tape->disk;
1009         struct ide_atapi_pc pc;
1010         int ret;
1011
1012         ide_debug_log(IDE_DBG_FUNC, "enter");
1013
1014         idetape_create_rewind_cmd(drive, &pc);
1015         ret = ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1016         if (ret)
1017                 return ret;
1018
1019         ret = ide_tape_read_position(drive);
1020         if (ret < 0)
1021                 return ret;
1022         return 0;
1023 }
1024
1025 /* mtio.h compatible commands should be issued to the chrdev interface. */
1026 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1027                                 unsigned long arg)
1028 {
1029         idetape_tape_t *tape = drive->driver_data;
1030         void __user *argp = (void __user *)arg;
1031
1032         struct idetape_config {
1033                 int dsc_rw_frequency;
1034                 int dsc_media_access_frequency;
1035                 int nr_stages;
1036         } config;
1037
1038         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%04x", cmd);
1039
1040         switch (cmd) {
1041         case 0x0340:
1042                 if (copy_from_user(&config, argp, sizeof(config)))
1043                         return -EFAULT;
1044                 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1045                 break;
1046         case 0x0350:
1047                 memset(&config, 0, sizeof(config));
1048                 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1049                 config.nr_stages = 1;
1050                 if (copy_to_user(argp, &config, sizeof(config)))
1051                         return -EFAULT;
1052                 break;
1053         default:
1054                 return -EIO;
1055         }
1056         return 0;
1057 }
1058
1059 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1060                                         int mt_count)
1061 {
1062         idetape_tape_t *tape = drive->driver_data;
1063         struct gendisk *disk = tape->disk;
1064         struct ide_atapi_pc pc;
1065         int retval, count = 0;
1066         int sprev = !!(tape->caps[4] & 0x20);
1067
1068
1069         ide_debug_log(IDE_DBG_FUNC, "mt_op: %d, mt_count: %d", mt_op, mt_count);
1070
1071         if (mt_count == 0)
1072                 return 0;
1073         if (MTBSF == mt_op || MTBSFM == mt_op) {
1074                 if (!sprev)
1075                         return -EIO;
1076                 mt_count = -mt_count;
1077         }
1078
1079         if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1080                 tape->valid = 0;
1081                 if (test_and_clear_bit(ilog2(IDE_AFLAG_FILEMARK),
1082                                        &drive->atapi_flags))
1083                         ++count;
1084                 ide_tape_discard_merge_buffer(drive, 0);
1085         }
1086
1087         switch (mt_op) {
1088         case MTFSF:
1089         case MTBSF:
1090                 idetape_create_space_cmd(&pc, mt_count - count,
1091                                          IDETAPE_SPACE_OVER_FILEMARK);
1092                 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1093         case MTFSFM:
1094         case MTBSFM:
1095                 if (!sprev)
1096                         return -EIO;
1097                 retval = idetape_space_over_filemarks(drive, MTFSF,
1098                                                       mt_count - count);
1099                 if (retval)
1100                         return retval;
1101                 count = (MTBSFM == mt_op ? 1 : -1);
1102                 return idetape_space_over_filemarks(drive, MTFSF, count);
1103         default:
1104                 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1105                                 mt_op);
1106                 return -EIO;
1107         }
1108 }
1109
1110 /*
1111  * Our character device read / write functions.
1112  *
1113  * The tape is optimized to maximize throughput when it is transferring an
1114  * integral number of the "continuous transfer limit", which is a parameter of
1115  * the specific tape (26kB on my particular tape, 32kB for Onstream).
1116  *
1117  * As of version 1.3 of the driver, the character device provides an abstract
1118  * continuous view of the media - any mix of block sizes (even 1 byte) on the
1119  * same backup/restore procedure is supported. The driver will internally
1120  * convert the requests to the recommended transfer unit, so that an unmatch
1121  * between the user's block size to the recommended size will only result in a
1122  * (slightly) increased driver overhead, but will no longer hit performance.
1123  * This is not applicable to Onstream.
1124  */
1125 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1126                                    size_t count, loff_t *ppos)
1127 {
1128         struct ide_tape_obj *tape = file->private_data;
1129         ide_drive_t *drive = tape->drive;
1130         size_t done = 0;
1131         ssize_t ret = 0;
1132         int rc;
1133
1134         ide_debug_log(IDE_DBG_FUNC, "count %Zd", count);
1135
1136         if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1137                 if (test_bit(ilog2(IDE_AFLAG_DETECT_BS), &drive->atapi_flags))
1138                         if (count > tape->blk_size &&
1139                             (count % tape->blk_size) == 0)
1140                                 tape->user_bs_factor = count / tape->blk_size;
1141         }
1142
1143         rc = idetape_init_rw(drive, IDETAPE_DIR_READ);
1144         if (rc < 0)
1145                 return rc;
1146
1147         while (done < count) {
1148                 size_t todo;
1149
1150                 /* refill if staging buffer is empty */
1151                 if (!tape->valid) {
1152                         /* If we are at a filemark, nothing more to read */
1153                         if (test_bit(ilog2(IDE_AFLAG_FILEMARK),
1154                                      &drive->atapi_flags))
1155                                 break;
1156                         /* read */
1157                         if (idetape_queue_rw_tail(drive, REQ_IDETAPE_READ,
1158                                                   tape->buffer_size) <= 0)
1159                                 break;
1160                 }
1161
1162                 /* copy out */
1163                 todo = min_t(size_t, count - done, tape->valid);
1164                 if (copy_to_user(buf + done, tape->cur, todo))
1165                         ret = -EFAULT;
1166
1167                 tape->cur += todo;
1168                 tape->valid -= todo;
1169                 done += todo;
1170         }
1171
1172         if (!done && test_bit(ilog2(IDE_AFLAG_FILEMARK), &drive->atapi_flags)) {
1173                 idetape_space_over_filemarks(drive, MTFSF, 1);
1174                 return 0;
1175         }
1176
1177         return ret ? ret : done;
1178 }
1179
1180 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
1181                                      size_t count, loff_t *ppos)
1182 {
1183         struct ide_tape_obj *tape = file->private_data;
1184         ide_drive_t *drive = tape->drive;
1185         size_t done = 0;
1186         ssize_t ret = 0;
1187         int rc;
1188
1189         /* The drive is write protected. */
1190         if (tape->write_prot)
1191                 return -EACCES;
1192
1193         ide_debug_log(IDE_DBG_FUNC, "count %Zd", count);
1194
1195         /* Initialize write operation */
1196         rc = idetape_init_rw(drive, IDETAPE_DIR_WRITE);
1197         if (rc < 0)
1198                 return rc;
1199
1200         while (done < count) {
1201                 size_t todo;
1202
1203                 /* flush if staging buffer is full */
1204                 if (tape->valid == tape->buffer_size &&
1205                     idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1206                                           tape->buffer_size) <= 0)
1207                         return rc;
1208
1209                 /* copy in */
1210                 todo = min_t(size_t, count - done,
1211                              tape->buffer_size - tape->valid);
1212                 if (copy_from_user(tape->cur, buf + done, todo))
1213                         ret = -EFAULT;
1214
1215                 tape->cur += todo;
1216                 tape->valid += todo;
1217                 done += todo;
1218         }
1219
1220         return ret ? ret : done;
1221 }
1222
1223 static int idetape_write_filemark(ide_drive_t *drive)
1224 {
1225         struct ide_tape_obj *tape = drive->driver_data;
1226         struct ide_atapi_pc pc;
1227
1228         /* Write a filemark */
1229         idetape_create_write_filemark_cmd(drive, &pc, 1);
1230         if (ide_queue_pc_tail(drive, tape->disk, &pc, NULL, 0)) {
1231                 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
1232                 return -EIO;
1233         }
1234         return 0;
1235 }
1236
1237 /*
1238  * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
1239  * requested.
1240  *
1241  * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
1242  * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
1243  * usually not supported.
1244  *
1245  * The following commands are currently not supported:
1246  *
1247  * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
1248  * MT_ST_WRITE_THRESHOLD.
1249  */
1250 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
1251 {
1252         idetape_tape_t *tape = drive->driver_data;
1253         struct gendisk *disk = tape->disk;
1254         struct ide_atapi_pc pc;
1255         int i, retval;
1256
1257         ide_debug_log(IDE_DBG_FUNC, "MTIOCTOP ioctl: mt_op: %d, mt_count: %d",
1258                       mt_op, mt_count);
1259
1260         switch (mt_op) {
1261         case MTFSF:
1262         case MTFSFM:
1263         case MTBSF:
1264         case MTBSFM:
1265                 if (!mt_count)
1266                         return 0;
1267                 return idetape_space_over_filemarks(drive, mt_op, mt_count);
1268         default:
1269                 break;
1270         }
1271
1272         switch (mt_op) {
1273         case MTWEOF:
1274                 if (tape->write_prot)
1275                         return -EACCES;
1276                 ide_tape_discard_merge_buffer(drive, 1);
1277                 for (i = 0; i < mt_count; i++) {
1278                         retval = idetape_write_filemark(drive);
1279                         if (retval)
1280                                 return retval;
1281                 }
1282                 return 0;
1283         case MTREW:
1284                 ide_tape_discard_merge_buffer(drive, 0);
1285                 if (idetape_rewind_tape(drive))
1286                         return -EIO;
1287                 return 0;
1288         case MTLOAD:
1289                 ide_tape_discard_merge_buffer(drive, 0);
1290                 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK);
1291         case MTUNLOAD:
1292         case MTOFFL:
1293                 /*
1294                  * If door is locked, attempt to unlock before
1295                  * attempting to eject.
1296                  */
1297                 if (tape->door_locked) {
1298                         if (!ide_set_media_lock(drive, disk, 0))
1299                                 tape->door_locked = DOOR_UNLOCKED;
1300                 }
1301                 ide_tape_discard_merge_buffer(drive, 0);
1302                 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK);
1303                 if (!retval)
1304                         clear_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
1305                                   &drive->atapi_flags);
1306                 return retval;
1307         case MTNOP:
1308                 ide_tape_discard_merge_buffer(drive, 0);
1309                 return idetape_flush_tape_buffers(drive);
1310         case MTRETEN:
1311                 ide_tape_discard_merge_buffer(drive, 0);
1312                 return ide_do_start_stop(drive, disk,
1313                         IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
1314         case MTEOM:
1315                 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
1316                 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1317         case MTERASE:
1318                 (void)idetape_rewind_tape(drive);
1319                 idetape_create_erase_cmd(&pc);
1320                 return ide_queue_pc_tail(drive, disk, &pc, NULL, 0);
1321         case MTSETBLK:
1322                 if (mt_count) {
1323                         if (mt_count < tape->blk_size ||
1324                             mt_count % tape->blk_size)
1325                                 return -EIO;
1326                         tape->user_bs_factor = mt_count / tape->blk_size;
1327                         clear_bit(ilog2(IDE_AFLAG_DETECT_BS),
1328                                   &drive->atapi_flags);
1329                 } else
1330                         set_bit(ilog2(IDE_AFLAG_DETECT_BS),
1331                                 &drive->atapi_flags);
1332                 return 0;
1333         case MTSEEK:
1334                 ide_tape_discard_merge_buffer(drive, 0);
1335                 return idetape_position_tape(drive,
1336                         mt_count * tape->user_bs_factor, tape->partition, 0);
1337         case MTSETPART:
1338                 ide_tape_discard_merge_buffer(drive, 0);
1339                 return idetape_position_tape(drive, 0, mt_count, 0);
1340         case MTFSR:
1341         case MTBSR:
1342         case MTLOCK:
1343                 retval = ide_set_media_lock(drive, disk, 1);
1344                 if (retval)
1345                         return retval;
1346                 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
1347                 return 0;
1348         case MTUNLOCK:
1349                 retval = ide_set_media_lock(drive, disk, 0);
1350                 if (retval)
1351                         return retval;
1352                 tape->door_locked = DOOR_UNLOCKED;
1353                 return 0;
1354         default:
1355                 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1356                                 mt_op);
1357                 return -EIO;
1358         }
1359 }
1360
1361 /*
1362  * Our character device ioctls. General mtio.h magnetic io commands are
1363  * supported here, and not in the corresponding block interface. Our own
1364  * ide-tape ioctls are supported on both interfaces.
1365  */
1366 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
1367                                 unsigned int cmd, unsigned long arg)
1368 {
1369         struct ide_tape_obj *tape = file->private_data;
1370         ide_drive_t *drive = tape->drive;
1371         struct mtop mtop;
1372         struct mtget mtget;
1373         struct mtpos mtpos;
1374         int block_offset = 0, position = tape->first_frame;
1375         void __user *argp = (void __user *)arg;
1376
1377         ide_debug_log(IDE_DBG_FUNC, "cmd: 0x%x", cmd);
1378
1379         if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1380                 ide_tape_flush_merge_buffer(drive);
1381                 idetape_flush_tape_buffers(drive);
1382         }
1383         if (cmd == MTIOCGET || cmd == MTIOCPOS) {
1384                 block_offset = tape->valid /
1385                         (tape->blk_size * tape->user_bs_factor);
1386                 position = ide_tape_read_position(drive);
1387                 if (position < 0)
1388                         return -EIO;
1389         }
1390         switch (cmd) {
1391         case MTIOCTOP:
1392                 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
1393                         return -EFAULT;
1394                 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
1395         case MTIOCGET:
1396                 memset(&mtget, 0, sizeof(struct mtget));
1397                 mtget.mt_type = MT_ISSCSI2;
1398                 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
1399                 mtget.mt_dsreg =
1400                         ((tape->blk_size * tape->user_bs_factor)
1401                          << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
1402
1403                 if (tape->drv_write_prot)
1404                         mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
1405
1406                 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
1407                         return -EFAULT;
1408                 return 0;
1409         case MTIOCPOS:
1410                 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
1411                 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
1412                         return -EFAULT;
1413                 return 0;
1414         default:
1415                 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1416                         ide_tape_discard_merge_buffer(drive, 1);
1417                 return idetape_blkdev_ioctl(drive, cmd, arg);
1418         }
1419 }
1420
1421 /*
1422  * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
1423  * block size with the reported value.
1424  */
1425 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
1426 {
1427         idetape_tape_t *tape = drive->driver_data;
1428         struct ide_atapi_pc pc;
1429         u8 buf[12];
1430
1431         idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
1432         if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
1433                 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
1434                 if (tape->blk_size == 0) {
1435                         printk(KERN_WARNING "ide-tape: Cannot deal with zero "
1436                                             "block size, assuming 32k\n");
1437                         tape->blk_size = 32768;
1438                 }
1439                 return;
1440         }
1441         tape->blk_size = (buf[4 + 5] << 16) +
1442                                 (buf[4 + 6] << 8)  +
1443                                  buf[4 + 7];
1444         tape->drv_write_prot = (buf[2] & 0x80) >> 7;
1445
1446         ide_debug_log(IDE_DBG_FUNC, "blk_size: %d, write_prot: %d",
1447                       tape->blk_size, tape->drv_write_prot);
1448 }
1449
1450 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
1451 {
1452         unsigned int minor = iminor(inode), i = minor & ~0xc0;
1453         ide_drive_t *drive;
1454         idetape_tape_t *tape;
1455         int retval;
1456
1457         if (i >= MAX_HWIFS * MAX_DRIVES)
1458                 return -ENXIO;
1459
1460         lock_kernel();
1461         tape = ide_tape_get(NULL, true, i);
1462         if (!tape) {
1463                 unlock_kernel();
1464                 return -ENXIO;
1465         }
1466
1467         drive = tape->drive;
1468         filp->private_data = tape;
1469
1470         ide_debug_log(IDE_DBG_FUNC, "enter");
1471
1472         /*
1473          * We really want to do nonseekable_open(inode, filp); here, but some
1474          * versions of tar incorrectly call lseek on tapes and bail out if that
1475          * fails.  So we disallow pread() and pwrite(), but permit lseeks.
1476          */
1477         filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
1478
1479
1480         if (test_and_set_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags)) {
1481                 retval = -EBUSY;
1482                 goto out_put_tape;
1483         }
1484
1485         retval = idetape_wait_ready(drive, 60 * HZ);
1486         if (retval) {
1487                 clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
1488                 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
1489                 goto out_put_tape;
1490         }
1491
1492         ide_tape_read_position(drive);
1493         if (!test_bit(ilog2(IDE_AFLAG_ADDRESS_VALID), &drive->atapi_flags))
1494                 (void)idetape_rewind_tape(drive);
1495
1496         /* Read block size and write protect status from drive. */
1497         ide_tape_get_bsize_from_bdesc(drive);
1498
1499         /* Set write protect flag if device is opened as read-only. */
1500         if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
1501                 tape->write_prot = 1;
1502         else
1503                 tape->write_prot = tape->drv_write_prot;
1504
1505         /* Make sure drive isn't write protected if user wants to write. */
1506         if (tape->write_prot) {
1507                 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
1508                     (filp->f_flags & O_ACCMODE) == O_RDWR) {
1509                         clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
1510                         retval = -EROFS;
1511                         goto out_put_tape;
1512                 }
1513         }
1514
1515         /* Lock the tape drive door so user can't eject. */
1516         if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
1517                 if (!ide_set_media_lock(drive, tape->disk, 1)) {
1518                         if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
1519                                 tape->door_locked = DOOR_LOCKED;
1520                 }
1521         }
1522         unlock_kernel();
1523         return 0;
1524
1525 out_put_tape:
1526         ide_tape_put(tape);
1527         unlock_kernel();
1528         return retval;
1529 }
1530
1531 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
1532 {
1533         idetape_tape_t *tape = drive->driver_data;
1534
1535         ide_tape_flush_merge_buffer(drive);
1536         tape->buf = kmalloc(tape->buffer_size, GFP_KERNEL);
1537         if (tape->buf != NULL) {
1538                 idetape_pad_zeros(drive, tape->blk_size *
1539                                 (tape->user_bs_factor - 1));
1540                 kfree(tape->buf);
1541                 tape->buf = NULL;
1542         }
1543         idetape_write_filemark(drive);
1544         idetape_flush_tape_buffers(drive);
1545         idetape_flush_tape_buffers(drive);
1546 }
1547
1548 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
1549 {
1550         struct ide_tape_obj *tape = filp->private_data;
1551         ide_drive_t *drive = tape->drive;
1552         unsigned int minor = iminor(inode);
1553
1554         lock_kernel();
1555         tape = drive->driver_data;
1556
1557         ide_debug_log(IDE_DBG_FUNC, "enter");
1558
1559         if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1560                 idetape_write_release(drive, minor);
1561         if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1562                 if (minor < 128)
1563                         ide_tape_discard_merge_buffer(drive, 1);
1564         }
1565
1566         if (minor < 128 && test_bit(ilog2(IDE_AFLAG_MEDIUM_PRESENT),
1567                                     &drive->atapi_flags))
1568                 (void) idetape_rewind_tape(drive);
1569
1570         if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
1571                 if (tape->door_locked == DOOR_LOCKED) {
1572                         if (!ide_set_media_lock(drive, tape->disk, 0))
1573                                 tape->door_locked = DOOR_UNLOCKED;
1574                 }
1575         }
1576         clear_bit(ilog2(IDE_AFLAG_BUSY), &drive->atapi_flags);
1577         ide_tape_put(tape);
1578         unlock_kernel();
1579         return 0;
1580 }
1581
1582 static void idetape_get_inquiry_results(ide_drive_t *drive)
1583 {
1584         idetape_tape_t *tape = drive->driver_data;
1585         struct ide_atapi_pc pc;
1586         u8 pc_buf[256];
1587         char fw_rev[4], vendor_id[8], product_id[16];
1588
1589         idetape_create_inquiry_cmd(&pc);
1590         if (ide_queue_pc_tail(drive, tape->disk, &pc, pc_buf, pc.req_xfer)) {
1591                 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
1592                                 tape->name);
1593                 return;
1594         }
1595         memcpy(vendor_id, &pc_buf[8], 8);
1596         memcpy(product_id, &pc_buf[16], 16);
1597         memcpy(fw_rev, &pc_buf[32], 4);
1598
1599         ide_fixstring(vendor_id, 8, 0);
1600         ide_fixstring(product_id, 16, 0);
1601         ide_fixstring(fw_rev, 4, 0);
1602
1603         printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n",
1604                         drive->name, tape->name, vendor_id, product_id, fw_rev);
1605 }
1606
1607 /*
1608  * Ask the tape about its various parameters. In particular, we will adjust our
1609  * data transfer buffer size to the recommended value as returned by the tape.
1610  */
1611 static void idetape_get_mode_sense_results(ide_drive_t *drive)
1612 {
1613         idetape_tape_t *tape = drive->driver_data;
1614         struct ide_atapi_pc pc;
1615         u8 buf[24], *caps;
1616         u8 speed, max_speed;
1617
1618         idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
1619         if (ide_queue_pc_tail(drive, tape->disk, &pc, buf, pc.req_xfer)) {
1620                 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
1621                                 " some default values\n");
1622                 tape->blk_size = 512;
1623                 put_unaligned(52,   (u16 *)&tape->caps[12]);
1624                 put_unaligned(540,  (u16 *)&tape->caps[14]);
1625                 put_unaligned(6*52, (u16 *)&tape->caps[16]);
1626                 return;
1627         }
1628         caps = buf + 4 + buf[3];
1629
1630         /* convert to host order and save for later use */
1631         speed = be16_to_cpup((__be16 *)&caps[14]);
1632         max_speed = be16_to_cpup((__be16 *)&caps[8]);
1633
1634         *(u16 *)&caps[8] = max_speed;
1635         *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]);
1636         *(u16 *)&caps[14] = speed;
1637         *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]);
1638
1639         if (!speed) {
1640                 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
1641                                 "(assuming 650KB/sec)\n", drive->name);
1642                 *(u16 *)&caps[14] = 650;
1643         }
1644         if (!max_speed) {
1645                 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
1646                                 "(assuming 650KB/sec)\n", drive->name);
1647                 *(u16 *)&caps[8] = 650;
1648         }
1649
1650         memcpy(&tape->caps, caps, 20);
1651
1652         /* device lacks locking support according to capabilities page */
1653         if ((caps[6] & 1) == 0)
1654                 drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING;
1655
1656         if (caps[7] & 0x02)
1657                 tape->blk_size = 512;
1658         else if (caps[7] & 0x04)
1659                 tape->blk_size = 1024;
1660 }
1661
1662 #ifdef CONFIG_IDE_PROC_FS
1663 #define ide_tape_devset_get(name, field) \
1664 static int get_##name(ide_drive_t *drive) \
1665 { \
1666         idetape_tape_t *tape = drive->driver_data; \
1667         return tape->field; \
1668 }
1669
1670 #define ide_tape_devset_set(name, field) \
1671 static int set_##name(ide_drive_t *drive, int arg) \
1672 { \
1673         idetape_tape_t *tape = drive->driver_data; \
1674         tape->field = arg; \
1675         return 0; \
1676 }
1677
1678 #define ide_tape_devset_rw_field(_name, _field) \
1679 ide_tape_devset_get(_name, _field) \
1680 ide_tape_devset_set(_name, _field) \
1681 IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name)
1682
1683 #define ide_tape_devset_r_field(_name, _field) \
1684 ide_tape_devset_get(_name, _field) \
1685 IDE_DEVSET(_name, 0, get_##_name, NULL)
1686
1687 static int mulf_tdsc(ide_drive_t *drive)        { return 1000; }
1688 static int divf_tdsc(ide_drive_t *drive)        { return   HZ; }
1689 static int divf_buffer(ide_drive_t *drive)      { return    2; }
1690 static int divf_buffer_size(ide_drive_t *drive) { return 1024; }
1691
1692 ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP);
1693
1694 ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq);
1695
1696 ide_tape_devset_r_field(avg_speed, avg_speed);
1697 ide_tape_devset_r_field(speed, caps[14]);
1698 ide_tape_devset_r_field(buffer, caps[16]);
1699 ide_tape_devset_r_field(buffer_size, buffer_size);
1700
1701 static const struct ide_proc_devset idetape_settings[] = {
1702         __IDE_PROC_DEVSET(avg_speed,    0, 0xffff, NULL, NULL),
1703         __IDE_PROC_DEVSET(buffer,       0, 0xffff, NULL, divf_buffer),
1704         __IDE_PROC_DEVSET(buffer_size,  0, 0xffff, NULL, divf_buffer_size),
1705         __IDE_PROC_DEVSET(dsc_overlap,  0,      1, NULL, NULL),
1706         __IDE_PROC_DEVSET(speed,        0, 0xffff, NULL, NULL),
1707         __IDE_PROC_DEVSET(tdsc,         IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX,
1708                                         mulf_tdsc, divf_tdsc),
1709         { NULL },
1710 };
1711 #endif
1712
1713 /*
1714  * The function below is called to:
1715  *
1716  * 1. Initialize our various state variables.
1717  * 2. Ask the tape for its capabilities.
1718  * 3. Allocate a buffer which will be used for data transfer. The buffer size
1719  * is chosen based on the recommendation which we received in step 2.
1720  *
1721  * Note that at this point ide.c already assigned us an irq, so that we can
1722  * queue requests here and wait for their completion.
1723  */
1724 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
1725 {
1726         unsigned long t;
1727         int speed;
1728         int buffer_size;
1729         u16 *ctl = (u16 *)&tape->caps[12];
1730
1731         ide_debug_log(IDE_DBG_FUNC, "minor: %d", minor);
1732
1733         drive->pc_callback = ide_tape_callback;
1734
1735         drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP;
1736
1737         if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
1738                 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
1739                                  tape->name);
1740                 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
1741         }
1742
1743         /* Seagate Travan drives do not support DSC overlap. */
1744         if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401"))
1745                 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
1746
1747         tape->minor = minor;
1748         tape->name[0] = 'h';
1749         tape->name[1] = 't';
1750         tape->name[2] = '0' + minor;
1751         tape->chrdev_dir = IDETAPE_DIR_NONE;
1752
1753         idetape_get_inquiry_results(drive);
1754         idetape_get_mode_sense_results(drive);
1755         ide_tape_get_bsize_from_bdesc(drive);
1756         tape->user_bs_factor = 1;
1757         tape->buffer_size = *ctl * tape->blk_size;
1758         while (tape->buffer_size > 0xffff) {
1759                 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
1760                 *ctl /= 2;
1761                 tape->buffer_size = *ctl * tape->blk_size;
1762         }
1763         buffer_size = tape->buffer_size;
1764
1765         /* select the "best" DSC read/write polling freq */
1766         speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
1767
1768         t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
1769
1770         /*
1771          * Ensure that the number we got makes sense; limit it within
1772          * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
1773          */
1774         tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
1775                                          IDETAPE_DSC_RW_MAX);
1776         printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
1777                 "%lums tDSC%s\n",
1778                 drive->name, tape->name, *(u16 *)&tape->caps[14],
1779                 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
1780                 tape->buffer_size / 1024,
1781                 tape->best_dsc_rw_freq * 1000 / HZ,
1782                 (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : "");
1783
1784         ide_proc_register_driver(drive, tape->driver);
1785 }
1786
1787 static void ide_tape_remove(ide_drive_t *drive)
1788 {
1789         idetape_tape_t *tape = drive->driver_data;
1790
1791         ide_proc_unregister_driver(drive, tape->driver);
1792         device_del(&tape->dev);
1793         ide_unregister_region(tape->disk);
1794
1795         mutex_lock(&idetape_ref_mutex);
1796         put_device(&tape->dev);
1797         mutex_unlock(&idetape_ref_mutex);
1798 }
1799
1800 static void ide_tape_release(struct device *dev)
1801 {
1802         struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj);
1803         ide_drive_t *drive = tape->drive;
1804         struct gendisk *g = tape->disk;
1805
1806         BUG_ON(tape->valid);
1807
1808         drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP;
1809         drive->driver_data = NULL;
1810         device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
1811         device_destroy(idetape_sysfs_class,
1812                         MKDEV(IDETAPE_MAJOR, tape->minor + 128));
1813         idetape_devs[tape->minor] = NULL;
1814         g->private_data = NULL;
1815         put_disk(g);
1816         kfree(tape);
1817 }
1818
1819 #ifdef CONFIG_IDE_PROC_FS
1820 static int idetape_name_proc_show(struct seq_file *m, void *v)
1821 {
1822         ide_drive_t     *drive = (ide_drive_t *) m->private;
1823         idetape_tape_t  *tape = drive->driver_data;
1824
1825         seq_printf(m, "%s\n", tape->name);
1826         return 0;
1827 }
1828
1829 static int idetape_name_proc_open(struct inode *inode, struct file *file)
1830 {
1831         return single_open(file, idetape_name_proc_show, PDE(inode)->data);
1832 }
1833
1834 static const struct file_operations idetape_name_proc_fops = {
1835         .owner          = THIS_MODULE,
1836         .open           = idetape_name_proc_open,
1837         .read           = seq_read,
1838         .llseek         = seq_lseek,
1839         .release        = single_release,
1840 };
1841
1842 static ide_proc_entry_t idetape_proc[] = {
1843         { "capacity",   S_IFREG|S_IRUGO,        &ide_capacity_proc_fops },
1844         { "name",       S_IFREG|S_IRUGO,        &idetape_name_proc_fops },
1845         {}
1846 };
1847
1848 static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive)
1849 {
1850         return idetape_proc;
1851 }
1852
1853 static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive)
1854 {
1855         return idetape_settings;
1856 }
1857 #endif
1858
1859 static int ide_tape_probe(ide_drive_t *);
1860
1861 static struct ide_driver idetape_driver = {
1862         .gen_driver = {
1863                 .owner          = THIS_MODULE,
1864                 .name           = "ide-tape",
1865                 .bus            = &ide_bus_type,
1866         },
1867         .probe                  = ide_tape_probe,
1868         .remove                 = ide_tape_remove,
1869         .version                = IDETAPE_VERSION,
1870         .do_request             = idetape_do_request,
1871 #ifdef CONFIG_IDE_PROC_FS
1872         .proc_entries           = ide_tape_proc_entries,
1873         .proc_devsets           = ide_tape_proc_devsets,
1874 #endif
1875 };
1876
1877 /* Our character device supporting functions, passed to register_chrdev. */
1878 static const struct file_operations idetape_fops = {
1879         .owner          = THIS_MODULE,
1880         .read           = idetape_chrdev_read,
1881         .write          = idetape_chrdev_write,
1882         .ioctl          = idetape_chrdev_ioctl,
1883         .open           = idetape_chrdev_open,
1884         .release        = idetape_chrdev_release,
1885 };
1886
1887 static int idetape_open(struct block_device *bdev, fmode_t mode)
1888 {
1889         struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk, false, 0);
1890
1891         if (!tape)
1892                 return -ENXIO;
1893
1894         return 0;
1895 }
1896
1897 static int idetape_release(struct gendisk *disk, fmode_t mode)
1898 {
1899         struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
1900
1901         ide_tape_put(tape);
1902         return 0;
1903 }
1904
1905 static int idetape_ioctl(struct block_device *bdev, fmode_t mode,
1906                         unsigned int cmd, unsigned long arg)
1907 {
1908         struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj);
1909         ide_drive_t *drive = tape->drive;
1910         int err = generic_ide_ioctl(drive, bdev, cmd, arg);
1911         if (err == -EINVAL)
1912                 err = idetape_blkdev_ioctl(drive, cmd, arg);
1913         return err;
1914 }
1915
1916 static const struct block_device_operations idetape_block_ops = {
1917         .owner          = THIS_MODULE,
1918         .open           = idetape_open,
1919         .release        = idetape_release,
1920         .locked_ioctl   = idetape_ioctl,
1921 };
1922
1923 static int ide_tape_probe(ide_drive_t *drive)
1924 {
1925         idetape_tape_t *tape;
1926         struct gendisk *g;
1927         int minor;
1928
1929         ide_debug_log(IDE_DBG_FUNC, "enter");
1930
1931         if (!strstr(DRV_NAME, drive->driver_req))
1932                 goto failed;
1933
1934         if (drive->media != ide_tape)
1935                 goto failed;
1936
1937         if ((drive->dev_flags & IDE_DFLAG_ID_READ) &&
1938             ide_check_atapi_device(drive, DRV_NAME) == 0) {
1939                 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
1940                                 " the driver\n", drive->name);
1941                 goto failed;
1942         }
1943         tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
1944         if (tape == NULL) {
1945                 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
1946                                 drive->name);
1947                 goto failed;
1948         }
1949
1950         g = alloc_disk(1 << PARTN_BITS);
1951         if (!g)
1952                 goto out_free_tape;
1953
1954         ide_init_disk(g, drive);
1955
1956         tape->dev.parent = &drive->gendev;
1957         tape->dev.release = ide_tape_release;
1958         dev_set_name(&tape->dev, dev_name(&drive->gendev));
1959
1960         if (device_register(&tape->dev))
1961                 goto out_free_disk;
1962
1963         tape->drive = drive;
1964         tape->driver = &idetape_driver;
1965         tape->disk = g;
1966
1967         g->private_data = &tape->driver;
1968
1969         drive->driver_data = tape;
1970
1971         mutex_lock(&idetape_ref_mutex);
1972         for (minor = 0; idetape_devs[minor]; minor++)
1973                 ;
1974         idetape_devs[minor] = tape;
1975         mutex_unlock(&idetape_ref_mutex);
1976
1977         idetape_setup(drive, tape, minor);
1978
1979         device_create(idetape_sysfs_class, &drive->gendev,
1980                       MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name);
1981         device_create(idetape_sysfs_class, &drive->gendev,
1982                       MKDEV(IDETAPE_MAJOR, minor + 128), NULL,
1983                       "n%s", tape->name);
1984
1985         g->fops = &idetape_block_ops;
1986         ide_register_region(g);
1987
1988         return 0;
1989
1990 out_free_disk:
1991         put_disk(g);
1992 out_free_tape:
1993         kfree(tape);
1994 failed:
1995         return -ENODEV;
1996 }
1997
1998 static void __exit idetape_exit(void)
1999 {
2000         driver_unregister(&idetape_driver.gen_driver);
2001         class_destroy(idetape_sysfs_class);
2002         unregister_chrdev(IDETAPE_MAJOR, "ht");
2003 }
2004
2005 static int __init idetape_init(void)
2006 {
2007         int error = 1;
2008         idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2009         if (IS_ERR(idetape_sysfs_class)) {
2010                 idetape_sysfs_class = NULL;
2011                 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2012                 error = -EBUSY;
2013                 goto out;
2014         }
2015
2016         if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2017                 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2018                                 " interface\n");
2019                 error = -EBUSY;
2020                 goto out_free_class;
2021         }
2022
2023         error = driver_register(&idetape_driver.gen_driver);
2024         if (error)
2025                 goto out_free_driver;
2026
2027         return 0;
2028
2029 out_free_driver:
2030         driver_unregister(&idetape_driver.gen_driver);
2031 out_free_class:
2032         class_destroy(idetape_sysfs_class);
2033 out:
2034         return error;
2035 }
2036
2037 MODULE_ALIAS("ide:*m-tape*");
2038 module_init(idetape_init);
2039 module_exit(idetape_exit);
2040 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2041 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2042 MODULE_LICENSE("GPL");