ide-tape.c revision 0578042db3191e1ac76b53d213f2a691c3e1eaed
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/slab.h> 35#include <linux/pci.h> 36#include <linux/ide.h> 37#include <linux/smp_lock.h> 38#include <linux/completion.h> 39#include <linux/bitops.h> 40#include <linux/mutex.h> 41#include <scsi/scsi.h> 42 43#include <asm/byteorder.h> 44#include <linux/irq.h> 45#include <linux/uaccess.h> 46#include <linux/io.h> 47#include <asm/unaligned.h> 48#include <linux/mtio.h> 49 50enum { 51 /* output errors only */ 52 DBG_ERR = (1 << 0), 53 /* output all sense key/asc */ 54 DBG_SENSE = (1 << 1), 55 /* info regarding all chrdev-related procedures */ 56 DBG_CHRDEV = (1 << 2), 57 /* all remaining procedures */ 58 DBG_PROCS = (1 << 3), 59}; 60 61/* define to see debug info */ 62#define IDETAPE_DEBUG_LOG 0 63 64#if IDETAPE_DEBUG_LOG 65#define debug_log(lvl, fmt, args...) \ 66{ \ 67 if (tape->debug_mask & lvl) \ 68 printk(KERN_INFO "ide-tape: " fmt, ## args); \ 69} 70#else 71#define debug_log(lvl, fmt, args...) do {} while (0) 72#endif 73 74/**************************** Tunable parameters *****************************/ 75/* 76 * After each failed packet command we issue a request sense command and retry 77 * the packet command IDETAPE_MAX_PC_RETRIES times. 78 * 79 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries. 80 */ 81#define IDETAPE_MAX_PC_RETRIES 3 82 83/* 84 * Some drives (for example, Seagate STT3401A Travan) require a very long 85 * timeout, because they don't return an interrupt or clear their busy bit 86 * until after the command completes (even retension commands). 87 */ 88#define IDETAPE_WAIT_CMD (900*HZ) 89 90/* 91 * The following parameter is used to select the point in the internal tape fifo 92 * in which we will start to refill the buffer. Decreasing the following 93 * parameter will improve the system's latency and interactive response, while 94 * using a high value might improve system throughput. 95 */ 96#define IDETAPE_FIFO_THRESHOLD 2 97 98/* 99 * DSC polling parameters. 100 * 101 * Polling for DSC (a single bit in the status register) is a very important 102 * function in ide-tape. There are two cases in which we poll for DSC: 103 * 104 * 1. Before a read/write packet command, to ensure that we can transfer data 105 * from/to the tape's data buffers, without causing an actual media access. 106 * In case the tape is not ready yet, we take out our request from the device 107 * request queue, so that ide.c could service requests from the other device 108 * on the same interface in the meantime. 109 * 110 * 2. After the successful initialization of a "media access packet command", 111 * which is a command that can take a long time to complete (the interval can 112 * range from several seconds to even an hour). Again, we postpone our request 113 * in the middle to free the bus for the other device. The polling frequency 114 * here should be lower than the read/write frequency since those media access 115 * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST 116 * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD 117 * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min). 118 * 119 * We also set a timeout for the timer, in case something goes wrong. The 120 * timeout should be longer then the maximum execution time of a tape operation. 121 */ 122 123/* DSC timings. */ 124#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */ 125#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */ 126#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */ 127#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */ 128#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */ 129#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */ 130#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */ 131 132/*************************** End of tunable parameters ***********************/ 133 134/* tape directions */ 135enum { 136 IDETAPE_DIR_NONE = (1 << 0), 137 IDETAPE_DIR_READ = (1 << 1), 138 IDETAPE_DIR_WRITE = (1 << 2), 139}; 140 141struct idetape_bh { 142 u32 b_size; 143 atomic_t b_count; 144 struct idetape_bh *b_reqnext; 145 char *b_data; 146}; 147 148/* Tape door status */ 149#define DOOR_UNLOCKED 0 150#define DOOR_LOCKED 1 151#define DOOR_EXPLICITLY_LOCKED 2 152 153/* Some defines for the SPACE command */ 154#define IDETAPE_SPACE_OVER_FILEMARK 1 155#define IDETAPE_SPACE_TO_EOD 3 156 157/* Some defines for the LOAD UNLOAD command */ 158#define IDETAPE_LU_LOAD_MASK 1 159#define IDETAPE_LU_RETENSION_MASK 2 160#define IDETAPE_LU_EOT_MASK 4 161 162/* Error codes returned in rq->errors to the higher part of the driver. */ 163#define IDETAPE_ERROR_GENERAL 101 164#define IDETAPE_ERROR_FILEMARK 102 165#define IDETAPE_ERROR_EOD 103 166 167/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 168#define IDETAPE_BLOCK_DESCRIPTOR 0 169#define IDETAPE_CAPABILITIES_PAGE 0x2a 170 171/* 172 * Most of our global data which we need to save even as we leave the driver due 173 * to an interrupt or a timer event is stored in the struct defined below. 174 */ 175typedef struct ide_tape_obj { 176 ide_drive_t *drive; 177 ide_driver_t *driver; 178 struct gendisk *disk; 179 struct kref kref; 180 181 /* 182 * pc points to the current processed packet command. 183 * 184 * failed_pc points to the last failed packet command, or contains 185 * NULL if we do not need to retry any packet command. This is 186 * required since an additional packet command is needed before the 187 * retry, to get detailed information on what went wrong. 188 */ 189 /* Current packet command */ 190 struct ide_atapi_pc *pc; 191 /* Last failed packet command */ 192 struct ide_atapi_pc *failed_pc; 193 /* used by REQ_IDETAPE_{READ,WRITE} requests */ 194 struct ide_atapi_pc queued_pc; 195 196 struct ide_atapi_pc request_sense_pc; 197 struct request request_sense_rq; 198 199 /* 200 * DSC polling variables. 201 * 202 * While polling for DSC we use postponed_rq to postpone the current 203 * request so that ide.c will be able to service pending requests on the 204 * other device. Note that at most we will have only one DSC (usually 205 * data transfer) request in the device request queue. 206 */ 207 struct request *postponed_rq; 208 /* The time in which we started polling for DSC */ 209 unsigned long dsc_polling_start; 210 /* Timer used to poll for dsc */ 211 struct timer_list dsc_timer; 212 /* Read/Write dsc polling frequency */ 213 unsigned long best_dsc_rw_freq; 214 unsigned long dsc_poll_freq; 215 unsigned long dsc_timeout; 216 217 /* Read position information */ 218 u8 partition; 219 /* Current block */ 220 unsigned int first_frame; 221 222 /* Last error information */ 223 u8 sense_key, asc, ascq; 224 225 /* Character device operation */ 226 unsigned int minor; 227 /* device name */ 228 char name[4]; 229 /* Current character device data transfer direction */ 230 u8 chrdev_dir; 231 232 /* tape block size, usually 512 or 1024 bytes */ 233 unsigned short blk_size; 234 int user_bs_factor; 235 236 /* Copy of the tape's Capabilities and Mechanical Page */ 237 u8 caps[20]; 238 239 /* 240 * Active data transfer request parameters. 241 * 242 * At most, there is only one ide-tape originated data transfer request 243 * in the device request queue. This allows ide.c to easily service 244 * requests from the other device when we postpone our active request. 245 */ 246 247 /* Data buffer size chosen based on the tape's recommendation */ 248 int buffer_size; 249 /* merge buffer */ 250 struct idetape_bh *merge_bh; 251 /* size of the merge buffer */ 252 int merge_bh_size; 253 /* pointer to current buffer head within the merge buffer */ 254 struct idetape_bh *bh; 255 char *b_data; 256 int b_count; 257 258 int pages_per_buffer; 259 /* Wasted space in each stage */ 260 int excess_bh_size; 261 262 /* protects the ide-tape queue */ 263 spinlock_t lock; 264 265 /* Measures average tape speed */ 266 unsigned long avg_time; 267 int avg_size; 268 int avg_speed; 269 270 /* the door is currently locked */ 271 int door_locked; 272 /* the tape hardware is write protected */ 273 char drv_write_prot; 274 /* the tape is write protected (hardware or opened as read-only) */ 275 char write_prot; 276 277 u32 debug_mask; 278} idetape_tape_t; 279 280static DEFINE_MUTEX(idetape_ref_mutex); 281 282static struct class *idetape_sysfs_class; 283 284#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref) 285 286#define ide_tape_g(disk) \ 287 container_of((disk)->private_data, struct ide_tape_obj, driver) 288 289static void ide_tape_release(struct kref *); 290 291static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 292{ 293 struct ide_tape_obj *tape = NULL; 294 295 mutex_lock(&idetape_ref_mutex); 296 tape = ide_tape_g(disk); 297 if (tape) { 298 if (ide_device_get(tape->drive)) 299 tape = NULL; 300 else 301 kref_get(&tape->kref); 302 } 303 mutex_unlock(&idetape_ref_mutex); 304 return tape; 305} 306 307static void ide_tape_put(struct ide_tape_obj *tape) 308{ 309 ide_drive_t *drive = tape->drive; 310 311 mutex_lock(&idetape_ref_mutex); 312 kref_put(&tape->kref, ide_tape_release); 313 ide_device_put(drive); 314 mutex_unlock(&idetape_ref_mutex); 315} 316 317/* 318 * The variables below are used for the character device interface. Additional 319 * state variables are defined in our ide_drive_t structure. 320 */ 321static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES]; 322 323#define ide_tape_f(file) ((file)->private_data) 324 325static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 326{ 327 struct ide_tape_obj *tape = NULL; 328 329 mutex_lock(&idetape_ref_mutex); 330 tape = idetape_devs[i]; 331 if (tape) 332 kref_get(&tape->kref); 333 mutex_unlock(&idetape_ref_mutex); 334 return tape; 335} 336 337static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 338 unsigned int bcount) 339{ 340 struct idetape_bh *bh = pc->bh; 341 int count; 342 343 while (bcount) { 344 if (bh == NULL) { 345 printk(KERN_ERR "ide-tape: bh == NULL in " 346 "idetape_input_buffers\n"); 347 ide_pad_transfer(drive, 0, bcount); 348 return; 349 } 350 count = min( 351 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 352 bcount); 353 drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data + 354 atomic_read(&bh->b_count), count); 355 bcount -= count; 356 atomic_add(count, &bh->b_count); 357 if (atomic_read(&bh->b_count) == bh->b_size) { 358 bh = bh->b_reqnext; 359 if (bh) 360 atomic_set(&bh->b_count, 0); 361 } 362 } 363 pc->bh = bh; 364} 365 366static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 367 unsigned int bcount) 368{ 369 struct idetape_bh *bh = pc->bh; 370 int count; 371 372 while (bcount) { 373 if (bh == NULL) { 374 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 375 __func__); 376 return; 377 } 378 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 379 drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); 380 bcount -= count; 381 pc->b_data += count; 382 pc->b_count -= count; 383 if (!pc->b_count) { 384 bh = bh->b_reqnext; 385 pc->bh = bh; 386 if (bh) { 387 pc->b_data = bh->b_data; 388 pc->b_count = atomic_read(&bh->b_count); 389 } 390 } 391 } 392} 393 394static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) 395{ 396 struct idetape_bh *bh = pc->bh; 397 int count; 398 unsigned int bcount = pc->xferred; 399 400 if (pc->flags & PC_FLAG_WRITING) 401 return; 402 while (bcount) { 403 if (bh == NULL) { 404 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 405 __func__); 406 return; 407 } 408 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 409 atomic_set(&bh->b_count, count); 410 if (atomic_read(&bh->b_count) == bh->b_size) 411 bh = bh->b_reqnext; 412 bcount -= count; 413 } 414 pc->bh = bh; 415} 416 417/* 418 * called on each failed packet command retry to analyze the request sense. We 419 * currently do not utilize this information. 420 */ 421static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 422{ 423 idetape_tape_t *tape = drive->driver_data; 424 struct ide_atapi_pc *pc = tape->failed_pc; 425 426 tape->sense_key = sense[2] & 0xF; 427 tape->asc = sense[12]; 428 tape->ascq = sense[13]; 429 430 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 431 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 432 433 /* Correct pc->xferred by asking the tape. */ 434 if (pc->flags & PC_FLAG_DMA_ERROR) { 435 pc->xferred = pc->req_xfer - 436 tape->blk_size * 437 get_unaligned_be32(&sense[3]); 438 idetape_update_buffers(drive, pc); 439 } 440 441 /* 442 * If error was the result of a zero-length read or write command, 443 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 444 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 445 */ 446 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 447 /* length == 0 */ 448 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 449 if (tape->sense_key == 5) { 450 /* don't report an error, everything's ok */ 451 pc->error = 0; 452 /* don't retry read/write */ 453 pc->flags |= PC_FLAG_ABORT; 454 } 455 } 456 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 457 pc->error = IDETAPE_ERROR_FILEMARK; 458 pc->flags |= PC_FLAG_ABORT; 459 } 460 if (pc->c[0] == WRITE_6) { 461 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 462 && tape->asc == 0x0 && tape->ascq == 0x2)) { 463 pc->error = IDETAPE_ERROR_EOD; 464 pc->flags |= PC_FLAG_ABORT; 465 } 466 } 467 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 468 if (tape->sense_key == 8) { 469 pc->error = IDETAPE_ERROR_EOD; 470 pc->flags |= PC_FLAG_ABORT; 471 } 472 if (!(pc->flags & PC_FLAG_ABORT) && 473 pc->xferred) 474 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 475 } 476} 477 478/* Free data buffers completely. */ 479static void ide_tape_kfree_buffer(idetape_tape_t *tape) 480{ 481 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 482 483 while (bh) { 484 u32 size = bh->b_size; 485 486 while (size) { 487 unsigned int order = fls(size >> PAGE_SHIFT)-1; 488 489 if (bh->b_data) 490 free_pages((unsigned long)bh->b_data, order); 491 492 size &= (order-1); 493 bh->b_data += (1 << order) * PAGE_SIZE; 494 } 495 prev_bh = bh; 496 bh = bh->b_reqnext; 497 kfree(prev_bh); 498 } 499} 500 501static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 502{ 503 struct request *rq = HWGROUP(drive)->rq; 504 idetape_tape_t *tape = drive->driver_data; 505 unsigned long flags; 506 int error; 507 508 debug_log(DBG_PROCS, "Enter %s\n", __func__); 509 510 switch (uptodate) { 511 case 0: error = IDETAPE_ERROR_GENERAL; break; 512 case 1: error = 0; break; 513 default: error = uptodate; 514 } 515 rq->errors = error; 516 if (error) 517 tape->failed_pc = NULL; 518 519 if (!blk_special_request(rq)) { 520 ide_end_request(drive, uptodate, nr_sects); 521 return 0; 522 } 523 524 spin_lock_irqsave(&tape->lock, flags); 525 526 ide_end_drive_cmd(drive, 0, 0); 527 528 spin_unlock_irqrestore(&tape->lock, flags); 529 return 0; 530} 531 532static void ide_tape_callback(ide_drive_t *drive) 533{ 534 idetape_tape_t *tape = drive->driver_data; 535 struct ide_atapi_pc *pc = tape->pc; 536 int uptodate = pc->error ? 0 : 1; 537 538 debug_log(DBG_PROCS, "Enter %s\n", __func__); 539 540 if (tape->failed_pc == pc) 541 tape->failed_pc = NULL; 542 543 if (pc->c[0] == REQUEST_SENSE) { 544 if (uptodate) 545 idetape_analyze_error(drive, pc->buf); 546 else 547 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 548 "itself - Aborting request!\n"); 549 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 550 struct request *rq = drive->hwif->hwgroup->rq; 551 int blocks = pc->xferred / tape->blk_size; 552 553 tape->avg_size += blocks * tape->blk_size; 554 555 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 556 tape->avg_speed = tape->avg_size * HZ / 557 (jiffies - tape->avg_time) / 1024; 558 tape->avg_size = 0; 559 tape->avg_time = jiffies; 560 } 561 562 tape->first_frame += blocks; 563 rq->current_nr_sectors -= blocks; 564 565 if (pc->error) 566 uptodate = pc->error; 567 } else if (pc->c[0] == READ_POSITION && uptodate) { 568 u8 *readpos = tape->pc->buf; 569 570 debug_log(DBG_SENSE, "BOP - %s\n", 571 (readpos[0] & 0x80) ? "Yes" : "No"); 572 debug_log(DBG_SENSE, "EOP - %s\n", 573 (readpos[0] & 0x40) ? "Yes" : "No"); 574 575 if (readpos[0] & 0x4) { 576 printk(KERN_INFO "ide-tape: Block location is unknown" 577 "to the tape\n"); 578 clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 579 uptodate = 0; 580 } else { 581 debug_log(DBG_SENSE, "Block Location - %u\n", 582 be32_to_cpup((__be32 *)&readpos[4])); 583 584 tape->partition = readpos[1]; 585 tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]); 586 set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 587 } 588 } 589 590 idetape_end_request(drive, uptodate, 0); 591} 592 593static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc) 594{ 595 ide_init_pc(pc); 596 pc->c[0] = REQUEST_SENSE; 597 pc->c[4] = 20; 598 pc->req_xfer = 20; 599} 600 601/* 602 * idetape_retry_pc is called when an error was detected during the 603 * last packet command. We queue a request sense packet command in 604 * the head of the request list. 605 */ 606static void idetape_retry_pc(ide_drive_t *drive) 607{ 608 struct ide_tape_obj *tape = drive->driver_data; 609 struct request *rq = &tape->request_sense_rq; 610 struct ide_atapi_pc *pc = &tape->request_sense_pc; 611 612 (void)ide_read_error(drive); 613 idetape_create_request_sense_cmd(pc); 614 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 615 ide_queue_pc_head(drive, tape->disk, pc, rq); 616} 617 618/* 619 * Postpone the current request so that ide.c will be able to service requests 620 * from another device on the same hwgroup while we are polling for DSC. 621 */ 622static void idetape_postpone_request(ide_drive_t *drive) 623{ 624 idetape_tape_t *tape = drive->driver_data; 625 626 debug_log(DBG_PROCS, "Enter %s\n", __func__); 627 628 tape->postponed_rq = HWGROUP(drive)->rq; 629 ide_stall_queue(drive, tape->dsc_poll_freq); 630} 631 632static void ide_tape_handle_dsc(ide_drive_t *drive) 633{ 634 idetape_tape_t *tape = drive->driver_data; 635 636 /* Media access command */ 637 tape->dsc_polling_start = jiffies; 638 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 639 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 640 /* Allow ide.c to handle other requests */ 641 idetape_postpone_request(drive); 642} 643 644static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 645 unsigned int bcount, int write) 646{ 647 if (write) 648 idetape_output_buffers(drive, pc, bcount); 649 else 650 idetape_input_buffers(drive, pc, bcount); 651 652 return bcount; 653} 654 655/* 656 * This is the usual interrupt handler which will be called during a packet 657 * command. We will transfer some of the data (as requested by the drive) and 658 * will re-point interrupt handler to us. When data transfer is finished, we 659 * will act according to the algorithm described before 660 * idetape_issue_pc. 661 */ 662static ide_startstop_t idetape_pc_intr(ide_drive_t *drive) 663{ 664 idetape_tape_t *tape = drive->driver_data; 665 666 return ide_pc_intr(drive, tape->pc, idetape_pc_intr, IDETAPE_WAIT_CMD, 667 NULL, idetape_update_buffers, idetape_retry_pc, 668 ide_tape_handle_dsc, ide_tape_io_buffers); 669} 670 671/* 672 * Packet Command Interface 673 * 674 * The current Packet Command is available in tape->pc, and will not change 675 * until we finish handling it. Each packet command is associated with a 676 * callback function that will be called when the command is finished. 677 * 678 * The handling will be done in three stages: 679 * 680 * 1. idetape_issue_pc will send the packet command to the drive, and will set 681 * the interrupt handler to idetape_pc_intr. 682 * 683 * 2. On each interrupt, idetape_pc_intr will be called. This step will be 684 * repeated until the device signals us that no more interrupts will be issued. 685 * 686 * 3. ATAPI Tape media access commands have immediate status with a delayed 687 * process. In case of a successful initiation of a media access packet command, 688 * the DSC bit will be set when the actual execution of the command is finished. 689 * Since the tape drive will not issue an interrupt, we have to poll for this 690 * event. In this case, we define the request as "low priority request" by 691 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 692 * exit the driver. 693 * 694 * ide.c will then give higher priority to requests which originate from the 695 * other device, until will change rq_status to RQ_ACTIVE. 696 * 697 * 4. When the packet command is finished, it will be checked for errors. 698 * 699 * 5. In case an error was found, we queue a request sense packet command in 700 * front of the request queue and retry the operation up to 701 * IDETAPE_MAX_PC_RETRIES times. 702 * 703 * 6. In case no error was found, or we decided to give up and not to retry 704 * again, the callback function will be called and then we will handle the next 705 * request. 706 */ 707static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 708{ 709 idetape_tape_t *tape = drive->driver_data; 710 711 return ide_transfer_pc(drive, tape->pc, idetape_pc_intr, 712 IDETAPE_WAIT_CMD, NULL); 713} 714 715static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 716 struct ide_atapi_pc *pc) 717{ 718 idetape_tape_t *tape = drive->driver_data; 719 720 if (tape->pc->c[0] == REQUEST_SENSE && 721 pc->c[0] == REQUEST_SENSE) { 722 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 723 "Two request sense in serial were issued\n"); 724 } 725 726 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 727 tape->failed_pc = pc; 728 /* Set the current packet command */ 729 tape->pc = pc; 730 731 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 732 (pc->flags & PC_FLAG_ABORT)) { 733 /* 734 * We will "abort" retrying a packet command in case legitimate 735 * error code was received (crossing a filemark, or end of the 736 * media, for example). 737 */ 738 if (!(pc->flags & PC_FLAG_ABORT)) { 739 if (!(pc->c[0] == TEST_UNIT_READY && 740 tape->sense_key == 2 && tape->asc == 4 && 741 (tape->ascq == 1 || tape->ascq == 8))) { 742 printk(KERN_ERR "ide-tape: %s: I/O error, " 743 "pc = %2x, key = %2x, " 744 "asc = %2x, ascq = %2x\n", 745 tape->name, pc->c[0], 746 tape->sense_key, tape->asc, 747 tape->ascq); 748 } 749 /* Giving up */ 750 pc->error = IDETAPE_ERROR_GENERAL; 751 } 752 tape->failed_pc = NULL; 753 drive->pc_callback(drive); 754 return ide_stopped; 755 } 756 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 757 758 pc->retries++; 759 760 return ide_issue_pc(drive, pc, idetape_transfer_pc, 761 IDETAPE_WAIT_CMD, NULL); 762} 763 764/* A mode sense command is used to "sense" tape parameters. */ 765static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 766{ 767 ide_init_pc(pc); 768 pc->c[0] = MODE_SENSE; 769 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 770 /* DBD = 1 - Don't return block descriptors */ 771 pc->c[1] = 8; 772 pc->c[2] = page_code; 773 /* 774 * Changed pc->c[3] to 0 (255 will at best return unused info). 775 * 776 * For SCSI this byte is defined as subpage instead of high byte 777 * of length and some IDE drives seem to interpret it this way 778 * and return an error when 255 is used. 779 */ 780 pc->c[3] = 0; 781 /* We will just discard data in that case */ 782 pc->c[4] = 255; 783 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 784 pc->req_xfer = 12; 785 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 786 pc->req_xfer = 24; 787 else 788 pc->req_xfer = 50; 789} 790 791static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 792{ 793 ide_hwif_t *hwif = drive->hwif; 794 idetape_tape_t *tape = drive->driver_data; 795 struct ide_atapi_pc *pc = tape->pc; 796 u8 stat; 797 798 stat = hwif->tp_ops->read_status(hwif); 799 800 if (stat & ATA_DSC) { 801 if (stat & ATA_ERR) { 802 /* Error detected */ 803 if (pc->c[0] != TEST_UNIT_READY) 804 printk(KERN_ERR "ide-tape: %s: I/O error, ", 805 tape->name); 806 /* Retry operation */ 807 idetape_retry_pc(drive); 808 return ide_stopped; 809 } 810 pc->error = 0; 811 } else { 812 pc->error = IDETAPE_ERROR_GENERAL; 813 tape->failed_pc = NULL; 814 } 815 drive->pc_callback(drive); 816 return ide_stopped; 817} 818 819static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 820 struct ide_atapi_pc *pc, struct request *rq, 821 u8 opcode) 822{ 823 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 824 unsigned int length = rq->current_nr_sectors; 825 826 ide_init_pc(pc); 827 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 828 pc->c[1] = 1; 829 pc->bh = bh; 830 pc->buf = NULL; 831 pc->buf_size = length * tape->blk_size; 832 pc->req_xfer = pc->buf_size; 833 if (pc->req_xfer == tape->buffer_size) 834 pc->flags |= PC_FLAG_DMA_OK; 835 836 if (opcode == READ_6) { 837 pc->c[0] = READ_6; 838 atomic_set(&bh->b_count, 0); 839 } else if (opcode == WRITE_6) { 840 pc->c[0] = WRITE_6; 841 pc->flags |= PC_FLAG_WRITING; 842 pc->b_data = bh->b_data; 843 pc->b_count = atomic_read(&bh->b_count); 844 } 845 846 memcpy(rq->cmd, pc->c, 12); 847} 848 849static ide_startstop_t idetape_do_request(ide_drive_t *drive, 850 struct request *rq, sector_t block) 851{ 852 ide_hwif_t *hwif = drive->hwif; 853 idetape_tape_t *tape = drive->driver_data; 854 struct ide_atapi_pc *pc = NULL; 855 struct request *postponed_rq = tape->postponed_rq; 856 u8 stat; 857 858 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 859 " current_nr_sectors: %u\n", 860 (unsigned long long)rq->sector, rq->nr_sectors, 861 rq->current_nr_sectors); 862 863 if (!blk_special_request(rq)) { 864 /* We do not support buffer cache originated requests. */ 865 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 866 "request queue (%d)\n", drive->name, rq->cmd_type); 867 ide_end_request(drive, 0, 0); 868 return ide_stopped; 869 } 870 871 /* Retry a failed packet command */ 872 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) { 873 pc = tape->failed_pc; 874 goto out; 875 } 876 877 if (postponed_rq != NULL) 878 if (rq != postponed_rq) { 879 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 880 "Two DSC requests were queued\n"); 881 idetape_end_request(drive, 0, 0); 882 return ide_stopped; 883 } 884 885 tape->postponed_rq = NULL; 886 887 /* 888 * If the tape is still busy, postpone our request and service 889 * the other device meanwhile. 890 */ 891 stat = hwif->tp_ops->read_status(hwif); 892 893 if (!drive->dsc_overlap && !(rq->cmd[13] & REQ_IDETAPE_PC2)) 894 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 895 896 if (drive->post_reset == 1) { 897 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 898 drive->post_reset = 0; 899 } 900 901 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 902 (stat & ATA_DSC) == 0) { 903 if (postponed_rq == NULL) { 904 tape->dsc_polling_start = jiffies; 905 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 906 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 907 } else if (time_after(jiffies, tape->dsc_timeout)) { 908 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 909 tape->name); 910 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 911 idetape_media_access_finished(drive); 912 return ide_stopped; 913 } else { 914 return ide_do_reset(drive); 915 } 916 } else if (time_after(jiffies, 917 tape->dsc_polling_start + 918 IDETAPE_DSC_MA_THRESHOLD)) 919 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 920 idetape_postpone_request(drive); 921 return ide_stopped; 922 } 923 if (rq->cmd[13] & REQ_IDETAPE_READ) { 924 pc = &tape->queued_pc; 925 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 926 goto out; 927 } 928 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 929 pc = &tape->queued_pc; 930 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 931 goto out; 932 } 933 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 934 pc = (struct ide_atapi_pc *) rq->buffer; 935 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 936 rq->cmd[13] |= REQ_IDETAPE_PC2; 937 goto out; 938 } 939 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 940 idetape_media_access_finished(drive); 941 return ide_stopped; 942 } 943 BUG(); 944 945out: 946 return idetape_issue_pc(drive, pc); 947} 948 949/* 950 * The function below uses __get_free_pages to allocate a data buffer of size 951 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 952 * much as possible. 953 * 954 * It returns a pointer to the newly allocated buffer, or NULL in case of 955 * failure. 956 */ 957static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 958 int full, int clear) 959{ 960 struct idetape_bh *prev_bh, *bh, *merge_bh; 961 int pages = tape->pages_per_buffer; 962 unsigned int order, b_allocd; 963 char *b_data = NULL; 964 965 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 966 bh = merge_bh; 967 if (bh == NULL) 968 goto abort; 969 970 order = fls(pages) - 1; 971 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 972 if (!bh->b_data) 973 goto abort; 974 b_allocd = (1 << order) * PAGE_SIZE; 975 pages &= (order-1); 976 977 if (clear) 978 memset(bh->b_data, 0, b_allocd); 979 bh->b_reqnext = NULL; 980 bh->b_size = b_allocd; 981 atomic_set(&bh->b_count, full ? bh->b_size : 0); 982 983 while (pages) { 984 order = fls(pages) - 1; 985 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 986 if (!b_data) 987 goto abort; 988 b_allocd = (1 << order) * PAGE_SIZE; 989 990 if (clear) 991 memset(b_data, 0, b_allocd); 992 993 /* newly allocated page frames below buffer header or ...*/ 994 if (bh->b_data == b_data + b_allocd) { 995 bh->b_size += b_allocd; 996 bh->b_data -= b_allocd; 997 if (full) 998 atomic_add(b_allocd, &bh->b_count); 999 continue; 1000 } 1001 /* they are above the header */ 1002 if (b_data == bh->b_data + bh->b_size) { 1003 bh->b_size += b_allocd; 1004 if (full) 1005 atomic_add(b_allocd, &bh->b_count); 1006 continue; 1007 } 1008 prev_bh = bh; 1009 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1010 if (!bh) { 1011 free_pages((unsigned long) b_data, order); 1012 goto abort; 1013 } 1014 bh->b_reqnext = NULL; 1015 bh->b_data = b_data; 1016 bh->b_size = b_allocd; 1017 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1018 prev_bh->b_reqnext = bh; 1019 1020 pages &= (order-1); 1021 } 1022 1023 bh->b_size -= tape->excess_bh_size; 1024 if (full) 1025 atomic_sub(tape->excess_bh_size, &bh->b_count); 1026 return merge_bh; 1027abort: 1028 ide_tape_kfree_buffer(tape); 1029 return NULL; 1030} 1031 1032static int idetape_copy_stage_from_user(idetape_tape_t *tape, 1033 const char __user *buf, int n) 1034{ 1035 struct idetape_bh *bh = tape->bh; 1036 int count; 1037 int ret = 0; 1038 1039 while (n) { 1040 if (bh == NULL) { 1041 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1042 __func__); 1043 return 1; 1044 } 1045 count = min((unsigned int) 1046 (bh->b_size - atomic_read(&bh->b_count)), 1047 (unsigned int)n); 1048 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 1049 count)) 1050 ret = 1; 1051 n -= count; 1052 atomic_add(count, &bh->b_count); 1053 buf += count; 1054 if (atomic_read(&bh->b_count) == bh->b_size) { 1055 bh = bh->b_reqnext; 1056 if (bh) 1057 atomic_set(&bh->b_count, 0); 1058 } 1059 } 1060 tape->bh = bh; 1061 return ret; 1062} 1063 1064static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1065 int n) 1066{ 1067 struct idetape_bh *bh = tape->bh; 1068 int count; 1069 int ret = 0; 1070 1071 while (n) { 1072 if (bh == NULL) { 1073 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1074 __func__); 1075 return 1; 1076 } 1077 count = min(tape->b_count, n); 1078 if (copy_to_user(buf, tape->b_data, count)) 1079 ret = 1; 1080 n -= count; 1081 tape->b_data += count; 1082 tape->b_count -= count; 1083 buf += count; 1084 if (!tape->b_count) { 1085 bh = bh->b_reqnext; 1086 tape->bh = bh; 1087 if (bh) { 1088 tape->b_data = bh->b_data; 1089 tape->b_count = atomic_read(&bh->b_count); 1090 } 1091 } 1092 } 1093 return ret; 1094} 1095 1096static void idetape_init_merge_buffer(idetape_tape_t *tape) 1097{ 1098 struct idetape_bh *bh = tape->merge_bh; 1099 tape->bh = tape->merge_bh; 1100 1101 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1102 atomic_set(&bh->b_count, 0); 1103 else { 1104 tape->b_data = bh->b_data; 1105 tape->b_count = atomic_read(&bh->b_count); 1106 } 1107} 1108 1109/* 1110 * Write a filemark if write_filemark=1. Flush the device buffers without 1111 * writing a filemark otherwise. 1112 */ 1113static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1114 struct ide_atapi_pc *pc, int write_filemark) 1115{ 1116 ide_init_pc(pc); 1117 pc->c[0] = WRITE_FILEMARKS; 1118 pc->c[4] = write_filemark; 1119 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1120} 1121 1122static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc) 1123{ 1124 ide_init_pc(pc); 1125 pc->c[0] = TEST_UNIT_READY; 1126} 1127 1128static void idetape_create_load_unload_cmd(ide_drive_t *drive, 1129 struct ide_atapi_pc *pc, int cmd) 1130{ 1131 ide_init_pc(pc); 1132 pc->c[0] = START_STOP; 1133 pc->c[4] = cmd; 1134 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1135} 1136 1137static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1138{ 1139 idetape_tape_t *tape = drive->driver_data; 1140 struct gendisk *disk = tape->disk; 1141 struct ide_atapi_pc pc; 1142 int load_attempted = 0; 1143 1144 /* Wait for the tape to become ready */ 1145 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1146 timeout += jiffies; 1147 while (time_before(jiffies, timeout)) { 1148 idetape_create_test_unit_ready_cmd(&pc); 1149 if (!ide_queue_pc_tail(drive, disk, &pc)) 1150 return 0; 1151 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1152 || (tape->asc == 0x3A)) { 1153 /* no media */ 1154 if (load_attempted) 1155 return -ENOMEDIUM; 1156 idetape_create_load_unload_cmd(drive, &pc, 1157 IDETAPE_LU_LOAD_MASK); 1158 ide_queue_pc_tail(drive, disk, &pc); 1159 load_attempted = 1; 1160 /* not about to be ready */ 1161 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1162 (tape->ascq == 1 || tape->ascq == 8))) 1163 return -EIO; 1164 msleep(100); 1165 } 1166 return -EIO; 1167} 1168 1169static int idetape_flush_tape_buffers(ide_drive_t *drive) 1170{ 1171 struct ide_tape_obj *tape = drive->driver_data; 1172 struct ide_atapi_pc pc; 1173 int rc; 1174 1175 idetape_create_write_filemark_cmd(drive, &pc, 0); 1176 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1177 if (rc) 1178 return rc; 1179 idetape_wait_ready(drive, 60 * 5 * HZ); 1180 return 0; 1181} 1182 1183static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1184{ 1185 ide_init_pc(pc); 1186 pc->c[0] = READ_POSITION; 1187 pc->req_xfer = 20; 1188} 1189 1190static int idetape_read_position(ide_drive_t *drive) 1191{ 1192 idetape_tape_t *tape = drive->driver_data; 1193 struct ide_atapi_pc pc; 1194 int position; 1195 1196 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1197 1198 idetape_create_read_position_cmd(&pc); 1199 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1200 return -1; 1201 position = tape->first_frame; 1202 return position; 1203} 1204 1205static void idetape_create_locate_cmd(ide_drive_t *drive, 1206 struct ide_atapi_pc *pc, 1207 unsigned int block, u8 partition, int skip) 1208{ 1209 ide_init_pc(pc); 1210 pc->c[0] = POSITION_TO_ELEMENT; 1211 pc->c[1] = 2; 1212 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1213 pc->c[8] = partition; 1214 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1215} 1216 1217static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1218{ 1219 idetape_tape_t *tape = drive->driver_data; 1220 1221 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1222 return; 1223 1224 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1225 tape->merge_bh_size = 0; 1226 if (tape->merge_bh != NULL) { 1227 ide_tape_kfree_buffer(tape); 1228 tape->merge_bh = NULL; 1229 } 1230 1231 tape->chrdev_dir = IDETAPE_DIR_NONE; 1232} 1233 1234/* 1235 * Position the tape to the requested block using the LOCATE packet command. 1236 * A READ POSITION command is then issued to check where we are positioned. Like 1237 * all higher level operations, we queue the commands at the tail of the request 1238 * queue and wait for their completion. 1239 */ 1240static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1241 u8 partition, int skip) 1242{ 1243 idetape_tape_t *tape = drive->driver_data; 1244 struct gendisk *disk = tape->disk; 1245 int retval; 1246 struct ide_atapi_pc pc; 1247 1248 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1249 __ide_tape_discard_merge_buffer(drive); 1250 idetape_wait_ready(drive, 60 * 5 * HZ); 1251 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1252 retval = ide_queue_pc_tail(drive, disk, &pc); 1253 if (retval) 1254 return (retval); 1255 1256 idetape_create_read_position_cmd(&pc); 1257 return ide_queue_pc_tail(drive, disk, &pc); 1258} 1259 1260static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1261 int restore_position) 1262{ 1263 idetape_tape_t *tape = drive->driver_data; 1264 int seek, position; 1265 1266 __ide_tape_discard_merge_buffer(drive); 1267 if (restore_position) { 1268 position = idetape_read_position(drive); 1269 seek = position > 0 ? position : 0; 1270 if (idetape_position_tape(drive, seek, 0, 0)) { 1271 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1272 " %s\n", tape->name, __func__); 1273 return; 1274 } 1275 } 1276} 1277 1278/* 1279 * Generate a read/write request for the block device interface and wait for it 1280 * to be serviced. 1281 */ 1282static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1283 struct idetape_bh *bh) 1284{ 1285 idetape_tape_t *tape = drive->driver_data; 1286 struct request *rq; 1287 int ret, errors; 1288 1289 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1290 1291 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1292 rq->cmd_type = REQ_TYPE_SPECIAL; 1293 rq->cmd[13] = cmd; 1294 rq->rq_disk = tape->disk; 1295 rq->special = (void *)bh; 1296 rq->sector = tape->first_frame; 1297 rq->nr_sectors = blocks; 1298 rq->current_nr_sectors = blocks; 1299 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1300 1301 errors = rq->errors; 1302 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1303 blk_put_request(rq); 1304 1305 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1306 return 0; 1307 1308 if (tape->merge_bh) 1309 idetape_init_merge_buffer(tape); 1310 if (errors == IDETAPE_ERROR_GENERAL) 1311 return -EIO; 1312 return ret; 1313} 1314 1315static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1316{ 1317 ide_init_pc(pc); 1318 pc->c[0] = INQUIRY; 1319 pc->c[4] = 254; 1320 pc->req_xfer = 254; 1321} 1322 1323static void idetape_create_rewind_cmd(ide_drive_t *drive, 1324 struct ide_atapi_pc *pc) 1325{ 1326 ide_init_pc(pc); 1327 pc->c[0] = REZERO_UNIT; 1328 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1329} 1330 1331static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1332{ 1333 ide_init_pc(pc); 1334 pc->c[0] = ERASE; 1335 pc->c[1] = 1; 1336 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1337} 1338 1339static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1340{ 1341 ide_init_pc(pc); 1342 pc->c[0] = SPACE; 1343 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1344 pc->c[1] = cmd; 1345 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1346} 1347 1348/* Queue up a character device originated write request. */ 1349static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1350{ 1351 idetape_tape_t *tape = drive->driver_data; 1352 1353 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1354 1355 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1356 blocks, tape->merge_bh); 1357} 1358 1359static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1360{ 1361 idetape_tape_t *tape = drive->driver_data; 1362 int blocks, min; 1363 struct idetape_bh *bh; 1364 1365 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1366 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1367 " but we are not writing.\n"); 1368 return; 1369 } 1370 if (tape->merge_bh_size > tape->buffer_size) { 1371 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1372 tape->merge_bh_size = tape->buffer_size; 1373 } 1374 if (tape->merge_bh_size) { 1375 blocks = tape->merge_bh_size / tape->blk_size; 1376 if (tape->merge_bh_size % tape->blk_size) { 1377 unsigned int i; 1378 1379 blocks++; 1380 i = tape->blk_size - tape->merge_bh_size % 1381 tape->blk_size; 1382 bh = tape->bh->b_reqnext; 1383 while (bh) { 1384 atomic_set(&bh->b_count, 0); 1385 bh = bh->b_reqnext; 1386 } 1387 bh = tape->bh; 1388 while (i) { 1389 if (bh == NULL) { 1390 printk(KERN_INFO "ide-tape: bug," 1391 " bh NULL\n"); 1392 break; 1393 } 1394 min = min(i, (unsigned int)(bh->b_size - 1395 atomic_read(&bh->b_count))); 1396 memset(bh->b_data + atomic_read(&bh->b_count), 1397 0, min); 1398 atomic_add(min, &bh->b_count); 1399 i -= min; 1400 bh = bh->b_reqnext; 1401 } 1402 } 1403 (void) idetape_add_chrdev_write_request(drive, blocks); 1404 tape->merge_bh_size = 0; 1405 } 1406 if (tape->merge_bh != NULL) { 1407 ide_tape_kfree_buffer(tape); 1408 tape->merge_bh = NULL; 1409 } 1410 tape->chrdev_dir = IDETAPE_DIR_NONE; 1411} 1412 1413static int idetape_init_read(ide_drive_t *drive) 1414{ 1415 idetape_tape_t *tape = drive->driver_data; 1416 int bytes_read; 1417 1418 /* Initialize read operation */ 1419 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1420 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1421 ide_tape_flush_merge_buffer(drive); 1422 idetape_flush_tape_buffers(drive); 1423 } 1424 if (tape->merge_bh || tape->merge_bh_size) { 1425 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1426 " 0 now\n"); 1427 tape->merge_bh_size = 0; 1428 } 1429 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1430 if (!tape->merge_bh) 1431 return -ENOMEM; 1432 tape->chrdev_dir = IDETAPE_DIR_READ; 1433 1434 /* 1435 * Issue a read 0 command to ensure that DSC handshake is 1436 * switched from completion mode to buffer available mode. 1437 * No point in issuing this if DSC overlap isn't supported, some 1438 * drives (Seagate STT3401A) will return an error. 1439 */ 1440 if (drive->dsc_overlap) { 1441 bytes_read = idetape_queue_rw_tail(drive, 1442 REQ_IDETAPE_READ, 0, 1443 tape->merge_bh); 1444 if (bytes_read < 0) { 1445 ide_tape_kfree_buffer(tape); 1446 tape->merge_bh = NULL; 1447 tape->chrdev_dir = IDETAPE_DIR_NONE; 1448 return bytes_read; 1449 } 1450 } 1451 } 1452 1453 return 0; 1454} 1455 1456/* called from idetape_chrdev_read() to service a chrdev read request. */ 1457static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1458{ 1459 idetape_tape_t *tape = drive->driver_data; 1460 1461 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1462 1463 /* If we are at a filemark, return a read length of 0 */ 1464 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1465 return 0; 1466 1467 idetape_init_read(drive); 1468 1469 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1470 tape->merge_bh); 1471} 1472 1473static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1474{ 1475 idetape_tape_t *tape = drive->driver_data; 1476 struct idetape_bh *bh; 1477 int blocks; 1478 1479 while (bcount) { 1480 unsigned int count; 1481 1482 bh = tape->merge_bh; 1483 count = min(tape->buffer_size, bcount); 1484 bcount -= count; 1485 blocks = count / tape->blk_size; 1486 while (count) { 1487 atomic_set(&bh->b_count, 1488 min(count, (unsigned int)bh->b_size)); 1489 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1490 count -= atomic_read(&bh->b_count); 1491 bh = bh->b_reqnext; 1492 } 1493 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1494 tape->merge_bh); 1495 } 1496} 1497 1498/* 1499 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1500 * currently support only one partition. 1501 */ 1502static int idetape_rewind_tape(ide_drive_t *drive) 1503{ 1504 struct ide_tape_obj *tape = drive->driver_data; 1505 struct gendisk *disk = tape->disk; 1506 int retval; 1507 struct ide_atapi_pc pc; 1508 1509 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1510 1511 idetape_create_rewind_cmd(drive, &pc); 1512 retval = ide_queue_pc_tail(drive, disk, &pc); 1513 if (retval) 1514 return retval; 1515 1516 idetape_create_read_position_cmd(&pc); 1517 retval = ide_queue_pc_tail(drive, disk, &pc); 1518 if (retval) 1519 return retval; 1520 return 0; 1521} 1522 1523/* mtio.h compatible commands should be issued to the chrdev interface. */ 1524static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1525 unsigned long arg) 1526{ 1527 idetape_tape_t *tape = drive->driver_data; 1528 void __user *argp = (void __user *)arg; 1529 1530 struct idetape_config { 1531 int dsc_rw_frequency; 1532 int dsc_media_access_frequency; 1533 int nr_stages; 1534 } config; 1535 1536 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1537 1538 switch (cmd) { 1539 case 0x0340: 1540 if (copy_from_user(&config, argp, sizeof(config))) 1541 return -EFAULT; 1542 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1543 break; 1544 case 0x0350: 1545 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1546 config.nr_stages = 1; 1547 if (copy_to_user(argp, &config, sizeof(config))) 1548 return -EFAULT; 1549 break; 1550 default: 1551 return -EIO; 1552 } 1553 return 0; 1554} 1555 1556static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1557 int mt_count) 1558{ 1559 idetape_tape_t *tape = drive->driver_data; 1560 struct gendisk *disk = tape->disk; 1561 struct ide_atapi_pc pc; 1562 int retval, count = 0; 1563 int sprev = !!(tape->caps[4] & 0x20); 1564 1565 if (mt_count == 0) 1566 return 0; 1567 if (MTBSF == mt_op || MTBSFM == mt_op) { 1568 if (!sprev) 1569 return -EIO; 1570 mt_count = -mt_count; 1571 } 1572 1573 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1574 tape->merge_bh_size = 0; 1575 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1576 ++count; 1577 ide_tape_discard_merge_buffer(drive, 0); 1578 } 1579 1580 switch (mt_op) { 1581 case MTFSF: 1582 case MTBSF: 1583 idetape_create_space_cmd(&pc, mt_count - count, 1584 IDETAPE_SPACE_OVER_FILEMARK); 1585 return ide_queue_pc_tail(drive, disk, &pc); 1586 case MTFSFM: 1587 case MTBSFM: 1588 if (!sprev) 1589 return -EIO; 1590 retval = idetape_space_over_filemarks(drive, MTFSF, 1591 mt_count - count); 1592 if (retval) 1593 return retval; 1594 count = (MTBSFM == mt_op ? 1 : -1); 1595 return idetape_space_over_filemarks(drive, MTFSF, count); 1596 default: 1597 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1598 mt_op); 1599 return -EIO; 1600 } 1601} 1602 1603/* 1604 * Our character device read / write functions. 1605 * 1606 * The tape is optimized to maximize throughput when it is transferring an 1607 * integral number of the "continuous transfer limit", which is a parameter of 1608 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1609 * 1610 * As of version 1.3 of the driver, the character device provides an abstract 1611 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1612 * same backup/restore procedure is supported. The driver will internally 1613 * convert the requests to the recommended transfer unit, so that an unmatch 1614 * between the user's block size to the recommended size will only result in a 1615 * (slightly) increased driver overhead, but will no longer hit performance. 1616 * This is not applicable to Onstream. 1617 */ 1618static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1619 size_t count, loff_t *ppos) 1620{ 1621 struct ide_tape_obj *tape = ide_tape_f(file); 1622 ide_drive_t *drive = tape->drive; 1623 ssize_t bytes_read, temp, actually_read = 0, rc; 1624 ssize_t ret = 0; 1625 u16 ctl = *(u16 *)&tape->caps[12]; 1626 1627 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1628 1629 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1630 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1631 if (count > tape->blk_size && 1632 (count % tape->blk_size) == 0) 1633 tape->user_bs_factor = count / tape->blk_size; 1634 } 1635 rc = idetape_init_read(drive); 1636 if (rc < 0) 1637 return rc; 1638 if (count == 0) 1639 return (0); 1640 if (tape->merge_bh_size) { 1641 actually_read = min((unsigned int)(tape->merge_bh_size), 1642 (unsigned int)count); 1643 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1644 ret = -EFAULT; 1645 buf += actually_read; 1646 tape->merge_bh_size -= actually_read; 1647 count -= actually_read; 1648 } 1649 while (count >= tape->buffer_size) { 1650 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1651 if (bytes_read <= 0) 1652 goto finish; 1653 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1654 ret = -EFAULT; 1655 buf += bytes_read; 1656 count -= bytes_read; 1657 actually_read += bytes_read; 1658 } 1659 if (count) { 1660 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1661 if (bytes_read <= 0) 1662 goto finish; 1663 temp = min((unsigned long)count, (unsigned long)bytes_read); 1664 if (idetape_copy_stage_to_user(tape, buf, temp)) 1665 ret = -EFAULT; 1666 actually_read += temp; 1667 tape->merge_bh_size = bytes_read-temp; 1668 } 1669finish: 1670 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1671 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1672 1673 idetape_space_over_filemarks(drive, MTFSF, 1); 1674 return 0; 1675 } 1676 1677 return ret ? ret : actually_read; 1678} 1679 1680static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1681 size_t count, loff_t *ppos) 1682{ 1683 struct ide_tape_obj *tape = ide_tape_f(file); 1684 ide_drive_t *drive = tape->drive; 1685 ssize_t actually_written = 0; 1686 ssize_t ret = 0; 1687 u16 ctl = *(u16 *)&tape->caps[12]; 1688 1689 /* The drive is write protected. */ 1690 if (tape->write_prot) 1691 return -EACCES; 1692 1693 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1694 1695 /* Initialize write operation */ 1696 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1697 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1698 ide_tape_discard_merge_buffer(drive, 1); 1699 if (tape->merge_bh || tape->merge_bh_size) { 1700 printk(KERN_ERR "ide-tape: merge_bh_size " 1701 "should be 0 now\n"); 1702 tape->merge_bh_size = 0; 1703 } 1704 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1705 if (!tape->merge_bh) 1706 return -ENOMEM; 1707 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1708 idetape_init_merge_buffer(tape); 1709 1710 /* 1711 * Issue a write 0 command to ensure that DSC handshake is 1712 * switched from completion mode to buffer available mode. No 1713 * point in issuing this if DSC overlap isn't supported, some 1714 * drives (Seagate STT3401A) will return an error. 1715 */ 1716 if (drive->dsc_overlap) { 1717 ssize_t retval = idetape_queue_rw_tail(drive, 1718 REQ_IDETAPE_WRITE, 0, 1719 tape->merge_bh); 1720 if (retval < 0) { 1721 ide_tape_kfree_buffer(tape); 1722 tape->merge_bh = NULL; 1723 tape->chrdev_dir = IDETAPE_DIR_NONE; 1724 return retval; 1725 } 1726 } 1727 } 1728 if (count == 0) 1729 return (0); 1730 if (tape->merge_bh_size) { 1731 if (tape->merge_bh_size >= tape->buffer_size) { 1732 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1733 tape->merge_bh_size = 0; 1734 } 1735 actually_written = min((unsigned int) 1736 (tape->buffer_size - tape->merge_bh_size), 1737 (unsigned int)count); 1738 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1739 ret = -EFAULT; 1740 buf += actually_written; 1741 tape->merge_bh_size += actually_written; 1742 count -= actually_written; 1743 1744 if (tape->merge_bh_size == tape->buffer_size) { 1745 ssize_t retval; 1746 tape->merge_bh_size = 0; 1747 retval = idetape_add_chrdev_write_request(drive, ctl); 1748 if (retval <= 0) 1749 return (retval); 1750 } 1751 } 1752 while (count >= tape->buffer_size) { 1753 ssize_t retval; 1754 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1755 ret = -EFAULT; 1756 buf += tape->buffer_size; 1757 count -= tape->buffer_size; 1758 retval = idetape_add_chrdev_write_request(drive, ctl); 1759 actually_written += tape->buffer_size; 1760 if (retval <= 0) 1761 return (retval); 1762 } 1763 if (count) { 1764 actually_written += count; 1765 if (idetape_copy_stage_from_user(tape, buf, count)) 1766 ret = -EFAULT; 1767 tape->merge_bh_size += count; 1768 } 1769 return ret ? ret : actually_written; 1770} 1771 1772static int idetape_write_filemark(ide_drive_t *drive) 1773{ 1774 struct ide_tape_obj *tape = drive->driver_data; 1775 struct ide_atapi_pc pc; 1776 1777 /* Write a filemark */ 1778 idetape_create_write_filemark_cmd(drive, &pc, 1); 1779 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1780 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1781 return -EIO; 1782 } 1783 return 0; 1784} 1785 1786/* 1787 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1788 * requested. 1789 * 1790 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1791 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1792 * usually not supported. 1793 * 1794 * The following commands are currently not supported: 1795 * 1796 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1797 * MT_ST_WRITE_THRESHOLD. 1798 */ 1799static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1800{ 1801 idetape_tape_t *tape = drive->driver_data; 1802 struct gendisk *disk = tape->disk; 1803 struct ide_atapi_pc pc; 1804 int i, retval; 1805 1806 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1807 mt_op, mt_count); 1808 1809 switch (mt_op) { 1810 case MTFSF: 1811 case MTFSFM: 1812 case MTBSF: 1813 case MTBSFM: 1814 if (!mt_count) 1815 return 0; 1816 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1817 default: 1818 break; 1819 } 1820 1821 switch (mt_op) { 1822 case MTWEOF: 1823 if (tape->write_prot) 1824 return -EACCES; 1825 ide_tape_discard_merge_buffer(drive, 1); 1826 for (i = 0; i < mt_count; i++) { 1827 retval = idetape_write_filemark(drive); 1828 if (retval) 1829 return retval; 1830 } 1831 return 0; 1832 case MTREW: 1833 ide_tape_discard_merge_buffer(drive, 0); 1834 if (idetape_rewind_tape(drive)) 1835 return -EIO; 1836 return 0; 1837 case MTLOAD: 1838 ide_tape_discard_merge_buffer(drive, 0); 1839 idetape_create_load_unload_cmd(drive, &pc, 1840 IDETAPE_LU_LOAD_MASK); 1841 return ide_queue_pc_tail(drive, disk, &pc); 1842 case MTUNLOAD: 1843 case MTOFFL: 1844 /* 1845 * If door is locked, attempt to unlock before 1846 * attempting to eject. 1847 */ 1848 if (tape->door_locked) { 1849 if (!ide_set_media_lock(drive, disk, 0)) 1850 tape->door_locked = DOOR_UNLOCKED; 1851 } 1852 ide_tape_discard_merge_buffer(drive, 0); 1853 idetape_create_load_unload_cmd(drive, &pc, 1854 !IDETAPE_LU_LOAD_MASK); 1855 retval = ide_queue_pc_tail(drive, disk, &pc); 1856 if (!retval) 1857 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1858 return retval; 1859 case MTNOP: 1860 ide_tape_discard_merge_buffer(drive, 0); 1861 return idetape_flush_tape_buffers(drive); 1862 case MTRETEN: 1863 ide_tape_discard_merge_buffer(drive, 0); 1864 idetape_create_load_unload_cmd(drive, &pc, 1865 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1866 return ide_queue_pc_tail(drive, disk, &pc); 1867 case MTEOM: 1868 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1869 return ide_queue_pc_tail(drive, disk, &pc); 1870 case MTERASE: 1871 (void)idetape_rewind_tape(drive); 1872 idetape_create_erase_cmd(&pc); 1873 return ide_queue_pc_tail(drive, disk, &pc); 1874 case MTSETBLK: 1875 if (mt_count) { 1876 if (mt_count < tape->blk_size || 1877 mt_count % tape->blk_size) 1878 return -EIO; 1879 tape->user_bs_factor = mt_count / tape->blk_size; 1880 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1881 } else 1882 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1883 return 0; 1884 case MTSEEK: 1885 ide_tape_discard_merge_buffer(drive, 0); 1886 return idetape_position_tape(drive, 1887 mt_count * tape->user_bs_factor, tape->partition, 0); 1888 case MTSETPART: 1889 ide_tape_discard_merge_buffer(drive, 0); 1890 return idetape_position_tape(drive, 0, mt_count, 0); 1891 case MTFSR: 1892 case MTBSR: 1893 case MTLOCK: 1894 retval = ide_set_media_lock(drive, disk, 1); 1895 if (retval) 1896 return retval; 1897 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1898 return 0; 1899 case MTUNLOCK: 1900 retval = ide_set_media_lock(drive, disk, 0); 1901 if (retval) 1902 return retval; 1903 tape->door_locked = DOOR_UNLOCKED; 1904 return 0; 1905 default: 1906 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1907 mt_op); 1908 return -EIO; 1909 } 1910} 1911 1912/* 1913 * Our character device ioctls. General mtio.h magnetic io commands are 1914 * supported here, and not in the corresponding block interface. Our own 1915 * ide-tape ioctls are supported on both interfaces. 1916 */ 1917static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1918 unsigned int cmd, unsigned long arg) 1919{ 1920 struct ide_tape_obj *tape = ide_tape_f(file); 1921 ide_drive_t *drive = tape->drive; 1922 struct mtop mtop; 1923 struct mtget mtget; 1924 struct mtpos mtpos; 1925 int block_offset = 0, position = tape->first_frame; 1926 void __user *argp = (void __user *)arg; 1927 1928 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1929 1930 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1931 ide_tape_flush_merge_buffer(drive); 1932 idetape_flush_tape_buffers(drive); 1933 } 1934 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1935 block_offset = tape->merge_bh_size / 1936 (tape->blk_size * tape->user_bs_factor); 1937 position = idetape_read_position(drive); 1938 if (position < 0) 1939 return -EIO; 1940 } 1941 switch (cmd) { 1942 case MTIOCTOP: 1943 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1944 return -EFAULT; 1945 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1946 case MTIOCGET: 1947 memset(&mtget, 0, sizeof(struct mtget)); 1948 mtget.mt_type = MT_ISSCSI2; 1949 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1950 mtget.mt_dsreg = 1951 ((tape->blk_size * tape->user_bs_factor) 1952 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1953 1954 if (tape->drv_write_prot) 1955 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1956 1957 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1958 return -EFAULT; 1959 return 0; 1960 case MTIOCPOS: 1961 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1962 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1963 return -EFAULT; 1964 return 0; 1965 default: 1966 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1967 ide_tape_discard_merge_buffer(drive, 1); 1968 return idetape_blkdev_ioctl(drive, cmd, arg); 1969 } 1970} 1971 1972/* 1973 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1974 * block size with the reported value. 1975 */ 1976static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1977{ 1978 idetape_tape_t *tape = drive->driver_data; 1979 struct ide_atapi_pc pc; 1980 1981 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1982 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1983 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1984 if (tape->blk_size == 0) { 1985 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1986 "block size, assuming 32k\n"); 1987 tape->blk_size = 32768; 1988 } 1989 return; 1990 } 1991 tape->blk_size = (pc.buf[4 + 5] << 16) + 1992 (pc.buf[4 + 6] << 8) + 1993 pc.buf[4 + 7]; 1994 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1995} 1996 1997static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1998{ 1999 unsigned int minor = iminor(inode), i = minor & ~0xc0; 2000 ide_drive_t *drive; 2001 idetape_tape_t *tape; 2002 int retval; 2003 2004 if (i >= MAX_HWIFS * MAX_DRIVES) 2005 return -ENXIO; 2006 2007 lock_kernel(); 2008 tape = ide_tape_chrdev_get(i); 2009 if (!tape) { 2010 unlock_kernel(); 2011 return -ENXIO; 2012 } 2013 2014 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2015 2016 /* 2017 * We really want to do nonseekable_open(inode, filp); here, but some 2018 * versions of tar incorrectly call lseek on tapes and bail out if that 2019 * fails. So we disallow pread() and pwrite(), but permit lseeks. 2020 */ 2021 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 2022 2023 drive = tape->drive; 2024 2025 filp->private_data = tape; 2026 2027 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 2028 retval = -EBUSY; 2029 goto out_put_tape; 2030 } 2031 2032 retval = idetape_wait_ready(drive, 60 * HZ); 2033 if (retval) { 2034 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2035 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 2036 goto out_put_tape; 2037 } 2038 2039 idetape_read_position(drive); 2040 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 2041 (void)idetape_rewind_tape(drive); 2042 2043 /* Read block size and write protect status from drive. */ 2044 ide_tape_get_bsize_from_bdesc(drive); 2045 2046 /* Set write protect flag if device is opened as read-only. */ 2047 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 2048 tape->write_prot = 1; 2049 else 2050 tape->write_prot = tape->drv_write_prot; 2051 2052 /* Make sure drive isn't write protected if user wants to write. */ 2053 if (tape->write_prot) { 2054 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 2055 (filp->f_flags & O_ACCMODE) == O_RDWR) { 2056 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2057 retval = -EROFS; 2058 goto out_put_tape; 2059 } 2060 } 2061 2062 /* Lock the tape drive door so user can't eject. */ 2063 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2064 if (!ide_set_media_lock(drive, tape->disk, 1)) { 2065 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 2066 tape->door_locked = DOOR_LOCKED; 2067 } 2068 } 2069 unlock_kernel(); 2070 return 0; 2071 2072out_put_tape: 2073 ide_tape_put(tape); 2074 unlock_kernel(); 2075 return retval; 2076} 2077 2078static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 2079{ 2080 idetape_tape_t *tape = drive->driver_data; 2081 2082 ide_tape_flush_merge_buffer(drive); 2083 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 2084 if (tape->merge_bh != NULL) { 2085 idetape_pad_zeros(drive, tape->blk_size * 2086 (tape->user_bs_factor - 1)); 2087 ide_tape_kfree_buffer(tape); 2088 tape->merge_bh = NULL; 2089 } 2090 idetape_write_filemark(drive); 2091 idetape_flush_tape_buffers(drive); 2092 idetape_flush_tape_buffers(drive); 2093} 2094 2095static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2096{ 2097 struct ide_tape_obj *tape = ide_tape_f(filp); 2098 ide_drive_t *drive = tape->drive; 2099 unsigned int minor = iminor(inode); 2100 2101 lock_kernel(); 2102 tape = drive->driver_data; 2103 2104 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2105 2106 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2107 idetape_write_release(drive, minor); 2108 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2109 if (minor < 128) 2110 ide_tape_discard_merge_buffer(drive, 1); 2111 } 2112 2113 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 2114 (void) idetape_rewind_tape(drive); 2115 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2116 if (tape->door_locked == DOOR_LOCKED) { 2117 if (!ide_set_media_lock(drive, tape->disk, 0)) 2118 tape->door_locked = DOOR_UNLOCKED; 2119 } 2120 } 2121 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2122 ide_tape_put(tape); 2123 unlock_kernel(); 2124 return 0; 2125} 2126 2127static void idetape_get_inquiry_results(ide_drive_t *drive) 2128{ 2129 idetape_tape_t *tape = drive->driver_data; 2130 struct ide_atapi_pc pc; 2131 char fw_rev[4], vendor_id[8], product_id[16]; 2132 2133 idetape_create_inquiry_cmd(&pc); 2134 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2135 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2136 tape->name); 2137 return; 2138 } 2139 memcpy(vendor_id, &pc.buf[8], 8); 2140 memcpy(product_id, &pc.buf[16], 16); 2141 memcpy(fw_rev, &pc.buf[32], 4); 2142 2143 ide_fixstring(vendor_id, 8, 0); 2144 ide_fixstring(product_id, 16, 0); 2145 ide_fixstring(fw_rev, 4, 0); 2146 2147 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2148 drive->name, tape->name, vendor_id, product_id, fw_rev); 2149} 2150 2151/* 2152 * Ask the tape about its various parameters. In particular, we will adjust our 2153 * data transfer buffer size to the recommended value as returned by the tape. 2154 */ 2155static void idetape_get_mode_sense_results(ide_drive_t *drive) 2156{ 2157 idetape_tape_t *tape = drive->driver_data; 2158 struct ide_atapi_pc pc; 2159 u8 *caps; 2160 u8 speed, max_speed; 2161 2162 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2163 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2164 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2165 " some default values\n"); 2166 tape->blk_size = 512; 2167 put_unaligned(52, (u16 *)&tape->caps[12]); 2168 put_unaligned(540, (u16 *)&tape->caps[14]); 2169 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2170 return; 2171 } 2172 caps = pc.buf + 4 + pc.buf[3]; 2173 2174 /* convert to host order and save for later use */ 2175 speed = be16_to_cpup((__be16 *)&caps[14]); 2176 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2177 2178 *(u16 *)&caps[8] = max_speed; 2179 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2180 *(u16 *)&caps[14] = speed; 2181 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2182 2183 if (!speed) { 2184 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2185 "(assuming 650KB/sec)\n", drive->name); 2186 *(u16 *)&caps[14] = 650; 2187 } 2188 if (!max_speed) { 2189 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2190 "(assuming 650KB/sec)\n", drive->name); 2191 *(u16 *)&caps[8] = 650; 2192 } 2193 2194 memcpy(&tape->caps, caps, 20); 2195 2196 /* device lacks locking support according to capabilities page */ 2197 if ((caps[6] & 1) == 0) 2198 drive->atapi_flags |= IDE_AFLAG_NO_DOORLOCK; 2199 2200 if (caps[7] & 0x02) 2201 tape->blk_size = 512; 2202 else if (caps[7] & 0x04) 2203 tape->blk_size = 1024; 2204} 2205 2206#ifdef CONFIG_IDE_PROC_FS 2207#define ide_tape_devset_get(name, field) \ 2208static int get_##name(ide_drive_t *drive) \ 2209{ \ 2210 idetape_tape_t *tape = drive->driver_data; \ 2211 return tape->field; \ 2212} 2213 2214#define ide_tape_devset_set(name, field) \ 2215static int set_##name(ide_drive_t *drive, int arg) \ 2216{ \ 2217 idetape_tape_t *tape = drive->driver_data; \ 2218 tape->field = arg; \ 2219 return 0; \ 2220} 2221 2222#define ide_tape_devset_rw(_name, _min, _max, _field, _mulf, _divf) \ 2223ide_tape_devset_get(_name, _field) \ 2224ide_tape_devset_set(_name, _field) \ 2225__IDE_DEVSET(_name, S_RW, _min, _max, get_##_name, set_##_name, _mulf, _divf) 2226 2227#define ide_tape_devset_r(_name, _min, _max, _field, _mulf, _divf) \ 2228ide_tape_devset_get(_name, _field) \ 2229__IDE_DEVSET(_name, S_READ, _min, _max, get_##_name, NULL, _mulf, _divf) 2230 2231static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2232static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2233static int divf_buffer(ide_drive_t *drive) { return 2; } 2234static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2235 2236ide_devset_rw(dsc_overlap, 0, 1, dsc_overlap); 2237 2238ide_tape_devset_rw(debug_mask, 0, 0xffff, debug_mask, NULL, NULL); 2239ide_tape_devset_rw(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2240 best_dsc_rw_freq, mulf_tdsc, divf_tdsc); 2241 2242ide_tape_devset_r(avg_speed, 0, 0xffff, avg_speed, NULL, NULL); 2243ide_tape_devset_r(speed, 0, 0xffff, caps[14], NULL, NULL); 2244ide_tape_devset_r(buffer, 0, 0xffff, caps[16], NULL, divf_buffer); 2245ide_tape_devset_r(buffer_size, 0, 0xffff, buffer_size, NULL, divf_buffer_size); 2246 2247static const struct ide_devset *idetape_settings[] = { 2248 &ide_devset_avg_speed, 2249 &ide_devset_buffer, 2250 &ide_devset_buffer_size, 2251 &ide_devset_debug_mask, 2252 &ide_devset_dsc_overlap, 2253 &ide_devset_speed, 2254 &ide_devset_tdsc, 2255 NULL 2256}; 2257#endif 2258 2259/* 2260 * The function below is called to: 2261 * 2262 * 1. Initialize our various state variables. 2263 * 2. Ask the tape for its capabilities. 2264 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2265 * is chosen based on the recommendation which we received in step 2. 2266 * 2267 * Note that at this point ide.c already assigned us an irq, so that we can 2268 * queue requests here and wait for their completion. 2269 */ 2270static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2271{ 2272 unsigned long t; 2273 int speed; 2274 int buffer_size; 2275 u8 gcw[2]; 2276 u16 *ctl = (u16 *)&tape->caps[12]; 2277 2278 drive->pc_callback = ide_tape_callback; 2279 2280 spin_lock_init(&tape->lock); 2281 drive->dsc_overlap = 1; 2282 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2283 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2284 tape->name); 2285 drive->dsc_overlap = 0; 2286 } 2287 /* Seagate Travan drives do not support DSC overlap. */ 2288 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2289 drive->dsc_overlap = 0; 2290 tape->minor = minor; 2291 tape->name[0] = 'h'; 2292 tape->name[1] = 't'; 2293 tape->name[2] = '0' + minor; 2294 tape->chrdev_dir = IDETAPE_DIR_NONE; 2295 2296 *((u16 *)&gcw) = drive->id[ATA_ID_CONFIG]; 2297 2298 /* Command packet DRQ type */ 2299 if (((gcw[0] & 0x60) >> 5) == 1) 2300 set_bit(IDE_AFLAG_DRQ_INTERRUPT, &drive->atapi_flags); 2301 2302 idetape_get_inquiry_results(drive); 2303 idetape_get_mode_sense_results(drive); 2304 ide_tape_get_bsize_from_bdesc(drive); 2305 tape->user_bs_factor = 1; 2306 tape->buffer_size = *ctl * tape->blk_size; 2307 while (tape->buffer_size > 0xffff) { 2308 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2309 *ctl /= 2; 2310 tape->buffer_size = *ctl * tape->blk_size; 2311 } 2312 buffer_size = tape->buffer_size; 2313 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2314 if (buffer_size % PAGE_SIZE) { 2315 tape->pages_per_buffer++; 2316 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2317 } 2318 2319 /* select the "best" DSC read/write polling freq */ 2320 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2321 2322 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2323 2324 /* 2325 * Ensure that the number we got makes sense; limit it within 2326 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2327 */ 2328 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2329 IDETAPE_DSC_RW_MAX); 2330 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2331 "%lums tDSC%s\n", 2332 drive->name, tape->name, *(u16 *)&tape->caps[14], 2333 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2334 tape->buffer_size / 1024, 2335 tape->best_dsc_rw_freq * 1000 / HZ, 2336 drive->using_dma ? ", DMA":""); 2337 2338 ide_proc_register_driver(drive, tape->driver); 2339} 2340 2341static void ide_tape_remove(ide_drive_t *drive) 2342{ 2343 idetape_tape_t *tape = drive->driver_data; 2344 2345 ide_proc_unregister_driver(drive, tape->driver); 2346 2347 ide_unregister_region(tape->disk); 2348 2349 ide_tape_put(tape); 2350} 2351 2352static void ide_tape_release(struct kref *kref) 2353{ 2354 struct ide_tape_obj *tape = to_ide_tape(kref); 2355 ide_drive_t *drive = tape->drive; 2356 struct gendisk *g = tape->disk; 2357 2358 BUG_ON(tape->merge_bh_size); 2359 2360 drive->dsc_overlap = 0; 2361 drive->driver_data = NULL; 2362 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2363 device_destroy(idetape_sysfs_class, 2364 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2365 idetape_devs[tape->minor] = NULL; 2366 g->private_data = NULL; 2367 put_disk(g); 2368 kfree(tape); 2369} 2370 2371#ifdef CONFIG_IDE_PROC_FS 2372static int proc_idetape_read_name 2373 (char *page, char **start, off_t off, int count, int *eof, void *data) 2374{ 2375 ide_drive_t *drive = (ide_drive_t *) data; 2376 idetape_tape_t *tape = drive->driver_data; 2377 char *out = page; 2378 int len; 2379 2380 len = sprintf(out, "%s\n", tape->name); 2381 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2382} 2383 2384static ide_proc_entry_t idetape_proc[] = { 2385 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2386 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2387 { NULL, 0, NULL, NULL } 2388}; 2389#endif 2390 2391static int ide_tape_probe(ide_drive_t *); 2392 2393static ide_driver_t idetape_driver = { 2394 .gen_driver = { 2395 .owner = THIS_MODULE, 2396 .name = "ide-tape", 2397 .bus = &ide_bus_type, 2398 }, 2399 .probe = ide_tape_probe, 2400 .remove = ide_tape_remove, 2401 .version = IDETAPE_VERSION, 2402 .media = ide_tape, 2403 .do_request = idetape_do_request, 2404 .end_request = idetape_end_request, 2405 .error = __ide_error, 2406#ifdef CONFIG_IDE_PROC_FS 2407 .proc = idetape_proc, 2408 .settings = idetape_settings, 2409#endif 2410}; 2411 2412/* Our character device supporting functions, passed to register_chrdev. */ 2413static const struct file_operations idetape_fops = { 2414 .owner = THIS_MODULE, 2415 .read = idetape_chrdev_read, 2416 .write = idetape_chrdev_write, 2417 .ioctl = idetape_chrdev_ioctl, 2418 .open = idetape_chrdev_open, 2419 .release = idetape_chrdev_release, 2420}; 2421 2422static int idetape_open(struct inode *inode, struct file *filp) 2423{ 2424 struct gendisk *disk = inode->i_bdev->bd_disk; 2425 struct ide_tape_obj *tape; 2426 2427 tape = ide_tape_get(disk); 2428 if (!tape) 2429 return -ENXIO; 2430 2431 return 0; 2432} 2433 2434static int idetape_release(struct inode *inode, struct file *filp) 2435{ 2436 struct gendisk *disk = inode->i_bdev->bd_disk; 2437 struct ide_tape_obj *tape = ide_tape_g(disk); 2438 2439 ide_tape_put(tape); 2440 2441 return 0; 2442} 2443 2444static int idetape_ioctl(struct inode *inode, struct file *file, 2445 unsigned int cmd, unsigned long arg) 2446{ 2447 struct block_device *bdev = inode->i_bdev; 2448 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 2449 ide_drive_t *drive = tape->drive; 2450 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 2451 if (err == -EINVAL) 2452 err = idetape_blkdev_ioctl(drive, cmd, arg); 2453 return err; 2454} 2455 2456static struct block_device_operations idetape_block_ops = { 2457 .owner = THIS_MODULE, 2458 .open = idetape_open, 2459 .release = idetape_release, 2460 .ioctl = idetape_ioctl, 2461}; 2462 2463static int ide_tape_probe(ide_drive_t *drive) 2464{ 2465 idetape_tape_t *tape; 2466 struct gendisk *g; 2467 int minor; 2468 2469 if (!strstr("ide-tape", drive->driver_req)) 2470 goto failed; 2471 2472 if (drive->media != ide_tape) 2473 goto failed; 2474 2475 if (drive->id_read == 1 && !ide_check_atapi_device(drive, DRV_NAME)) { 2476 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2477 " the driver\n", drive->name); 2478 goto failed; 2479 } 2480 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2481 if (tape == NULL) { 2482 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2483 drive->name); 2484 goto failed; 2485 } 2486 2487 g = alloc_disk(1 << PARTN_BITS); 2488 if (!g) 2489 goto out_free_tape; 2490 2491 ide_init_disk(g, drive); 2492 2493 kref_init(&tape->kref); 2494 2495 tape->drive = drive; 2496 tape->driver = &idetape_driver; 2497 tape->disk = g; 2498 2499 g->private_data = &tape->driver; 2500 2501 drive->driver_data = tape; 2502 2503 mutex_lock(&idetape_ref_mutex); 2504 for (minor = 0; idetape_devs[minor]; minor++) 2505 ; 2506 idetape_devs[minor] = tape; 2507 mutex_unlock(&idetape_ref_mutex); 2508 2509 idetape_setup(drive, tape, minor); 2510 2511 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2512 MKDEV(IDETAPE_MAJOR, minor), NULL, 2513 "%s", tape->name); 2514 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2515 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2516 "n%s", tape->name); 2517 2518 g->fops = &idetape_block_ops; 2519 ide_register_region(g); 2520 2521 return 0; 2522 2523out_free_tape: 2524 kfree(tape); 2525failed: 2526 return -ENODEV; 2527} 2528 2529static void __exit idetape_exit(void) 2530{ 2531 driver_unregister(&idetape_driver.gen_driver); 2532 class_destroy(idetape_sysfs_class); 2533 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2534} 2535 2536static int __init idetape_init(void) 2537{ 2538 int error = 1; 2539 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2540 if (IS_ERR(idetape_sysfs_class)) { 2541 idetape_sysfs_class = NULL; 2542 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2543 error = -EBUSY; 2544 goto out; 2545 } 2546 2547 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2548 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2549 " interface\n"); 2550 error = -EBUSY; 2551 goto out_free_class; 2552 } 2553 2554 error = driver_register(&idetape_driver.gen_driver); 2555 if (error) 2556 goto out_free_driver; 2557 2558 return 0; 2559 2560out_free_driver: 2561 driver_unregister(&idetape_driver.gen_driver); 2562out_free_class: 2563 class_destroy(idetape_sysfs_class); 2564out: 2565 return error; 2566} 2567 2568MODULE_ALIAS("ide:*m-tape*"); 2569module_init(idetape_init); 2570module_exit(idetape_exit); 2571MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2572MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2573MODULE_LICENSE("GPL"); 2574