ide-tape.c revision 5aeddf907f149cae7e19b7c23ccea3823d00698c
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 * The following parameter is used to select the point in the internal tape fifo 85 * in which we will start to refill the buffer. Decreasing the following 86 * parameter will improve the system's latency and interactive response, while 87 * using a high value might improve system throughput. 88 */ 89#define IDETAPE_FIFO_THRESHOLD 2 90 91/* 92 * DSC polling parameters. 93 * 94 * Polling for DSC (a single bit in the status register) is a very important 95 * function in ide-tape. There are two cases in which we poll for DSC: 96 * 97 * 1. Before a read/write packet command, to ensure that we can transfer data 98 * from/to the tape's data buffers, without causing an actual media access. 99 * In case the tape is not ready yet, we take out our request from the device 100 * request queue, so that ide.c could service requests from the other device 101 * on the same interface in the meantime. 102 * 103 * 2. After the successful initialization of a "media access packet command", 104 * which is a command that can take a long time to complete (the interval can 105 * range from several seconds to even an hour). Again, we postpone our request 106 * in the middle to free the bus for the other device. The polling frequency 107 * here should be lower than the read/write frequency since those media access 108 * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST 109 * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD 110 * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min). 111 * 112 * We also set a timeout for the timer, in case something goes wrong. The 113 * timeout should be longer then the maximum execution time of a tape operation. 114 */ 115 116/* DSC timings. */ 117#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */ 118#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */ 119#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */ 120#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */ 121#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */ 122#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */ 123#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */ 124 125/*************************** End of tunable parameters ***********************/ 126 127/* tape directions */ 128enum { 129 IDETAPE_DIR_NONE = (1 << 0), 130 IDETAPE_DIR_READ = (1 << 1), 131 IDETAPE_DIR_WRITE = (1 << 2), 132}; 133 134struct idetape_bh { 135 u32 b_size; 136 atomic_t b_count; 137 struct idetape_bh *b_reqnext; 138 char *b_data; 139}; 140 141/* Tape door status */ 142#define DOOR_UNLOCKED 0 143#define DOOR_LOCKED 1 144#define DOOR_EXPLICITLY_LOCKED 2 145 146/* Some defines for the SPACE command */ 147#define IDETAPE_SPACE_OVER_FILEMARK 1 148#define IDETAPE_SPACE_TO_EOD 3 149 150/* Some defines for the LOAD UNLOAD command */ 151#define IDETAPE_LU_LOAD_MASK 1 152#define IDETAPE_LU_RETENSION_MASK 2 153#define IDETAPE_LU_EOT_MASK 4 154 155/* Error codes returned in rq->errors to the higher part of the driver. */ 156#define IDETAPE_ERROR_GENERAL 101 157#define IDETAPE_ERROR_FILEMARK 102 158#define IDETAPE_ERROR_EOD 103 159 160/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 161#define IDETAPE_BLOCK_DESCRIPTOR 0 162#define IDETAPE_CAPABILITIES_PAGE 0x2a 163 164/* 165 * Most of our global data which we need to save even as we leave the driver due 166 * to an interrupt or a timer event is stored in the struct defined below. 167 */ 168typedef struct ide_tape_obj { 169 ide_drive_t *drive; 170 ide_driver_t *driver; 171 struct gendisk *disk; 172 struct kref kref; 173 174 /* 175 * failed_pc points to the last failed packet command, or contains 176 * NULL if we do not need to retry any packet command. This is 177 * required since an additional packet command is needed before the 178 * retry, to get detailed information on what went wrong. 179 */ 180 /* Last failed packet command */ 181 struct ide_atapi_pc *failed_pc; 182 /* used by REQ_IDETAPE_{READ,WRITE} requests */ 183 struct ide_atapi_pc queued_pc; 184 185 /* 186 * DSC polling variables. 187 * 188 * While polling for DSC we use postponed_rq to postpone the current 189 * request so that ide.c will be able to service pending requests on the 190 * other device. Note that at most we will have only one DSC (usually 191 * data transfer) request in the device request queue. 192 */ 193 struct request *postponed_rq; 194 /* The time in which we started polling for DSC */ 195 unsigned long dsc_polling_start; 196 /* Timer used to poll for dsc */ 197 struct timer_list dsc_timer; 198 /* Read/Write dsc polling frequency */ 199 unsigned long best_dsc_rw_freq; 200 unsigned long dsc_poll_freq; 201 unsigned long dsc_timeout; 202 203 /* Read position information */ 204 u8 partition; 205 /* Current block */ 206 unsigned int first_frame; 207 208 /* Last error information */ 209 u8 sense_key, asc, ascq; 210 211 /* Character device operation */ 212 unsigned int minor; 213 /* device name */ 214 char name[4]; 215 /* Current character device data transfer direction */ 216 u8 chrdev_dir; 217 218 /* tape block size, usually 512 or 1024 bytes */ 219 unsigned short blk_size; 220 int user_bs_factor; 221 222 /* Copy of the tape's Capabilities and Mechanical Page */ 223 u8 caps[20]; 224 225 /* 226 * Active data transfer request parameters. 227 * 228 * At most, there is only one ide-tape originated data transfer request 229 * in the device request queue. This allows ide.c to easily service 230 * requests from the other device when we postpone our active request. 231 */ 232 233 /* Data buffer size chosen based on the tape's recommendation */ 234 int buffer_size; 235 /* merge buffer */ 236 struct idetape_bh *merge_bh; 237 /* size of the merge buffer */ 238 int merge_bh_size; 239 /* pointer to current buffer head within the merge buffer */ 240 struct idetape_bh *bh; 241 char *b_data; 242 int b_count; 243 244 int pages_per_buffer; 245 /* Wasted space in each stage */ 246 int excess_bh_size; 247 248 /* protects the ide-tape queue */ 249 spinlock_t lock; 250 251 /* Measures average tape speed */ 252 unsigned long avg_time; 253 int avg_size; 254 int avg_speed; 255 256 /* the door is currently locked */ 257 int door_locked; 258 /* the tape hardware is write protected */ 259 char drv_write_prot; 260 /* the tape is write protected (hardware or opened as read-only) */ 261 char write_prot; 262 263 u32 debug_mask; 264} idetape_tape_t; 265 266static DEFINE_MUTEX(idetape_ref_mutex); 267 268static struct class *idetape_sysfs_class; 269 270static void ide_tape_release(struct kref *); 271 272static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 273{ 274 struct ide_tape_obj *tape = NULL; 275 276 mutex_lock(&idetape_ref_mutex); 277 tape = ide_drv_g(disk, ide_tape_obj); 278 if (tape) { 279 if (ide_device_get(tape->drive)) 280 tape = NULL; 281 else 282 kref_get(&tape->kref); 283 } 284 mutex_unlock(&idetape_ref_mutex); 285 return tape; 286} 287 288static void ide_tape_put(struct ide_tape_obj *tape) 289{ 290 ide_drive_t *drive = tape->drive; 291 292 mutex_lock(&idetape_ref_mutex); 293 kref_put(&tape->kref, ide_tape_release); 294 ide_device_put(drive); 295 mutex_unlock(&idetape_ref_mutex); 296} 297 298/* 299 * The variables below are used for the character device interface. Additional 300 * state variables are defined in our ide_drive_t structure. 301 */ 302static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES]; 303 304static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 305{ 306 struct ide_tape_obj *tape = NULL; 307 308 mutex_lock(&idetape_ref_mutex); 309 tape = idetape_devs[i]; 310 if (tape) 311 kref_get(&tape->kref); 312 mutex_unlock(&idetape_ref_mutex); 313 return tape; 314} 315 316static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 317 unsigned int bcount) 318{ 319 struct idetape_bh *bh = pc->bh; 320 int count; 321 322 while (bcount) { 323 if (bh == NULL) { 324 printk(KERN_ERR "ide-tape: bh == NULL in " 325 "idetape_input_buffers\n"); 326 ide_pad_transfer(drive, 0, bcount); 327 return; 328 } 329 count = min( 330 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 331 bcount); 332 drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data + 333 atomic_read(&bh->b_count), count); 334 bcount -= count; 335 atomic_add(count, &bh->b_count); 336 if (atomic_read(&bh->b_count) == bh->b_size) { 337 bh = bh->b_reqnext; 338 if (bh) 339 atomic_set(&bh->b_count, 0); 340 } 341 } 342 pc->bh = bh; 343} 344 345static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 346 unsigned int bcount) 347{ 348 struct idetape_bh *bh = pc->bh; 349 int count; 350 351 while (bcount) { 352 if (bh == NULL) { 353 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 354 __func__); 355 return; 356 } 357 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 358 drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); 359 bcount -= count; 360 pc->b_data += count; 361 pc->b_count -= count; 362 if (!pc->b_count) { 363 bh = bh->b_reqnext; 364 pc->bh = bh; 365 if (bh) { 366 pc->b_data = bh->b_data; 367 pc->b_count = atomic_read(&bh->b_count); 368 } 369 } 370 } 371} 372 373static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) 374{ 375 struct idetape_bh *bh = pc->bh; 376 int count; 377 unsigned int bcount = pc->xferred; 378 379 if (pc->flags & PC_FLAG_WRITING) 380 return; 381 while (bcount) { 382 if (bh == NULL) { 383 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 384 __func__); 385 return; 386 } 387 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 388 atomic_set(&bh->b_count, count); 389 if (atomic_read(&bh->b_count) == bh->b_size) 390 bh = bh->b_reqnext; 391 bcount -= count; 392 } 393 pc->bh = bh; 394} 395 396/* 397 * called on each failed packet command retry to analyze the request sense. We 398 * currently do not utilize this information. 399 */ 400static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 401{ 402 idetape_tape_t *tape = drive->driver_data; 403 struct ide_atapi_pc *pc = tape->failed_pc; 404 405 tape->sense_key = sense[2] & 0xF; 406 tape->asc = sense[12]; 407 tape->ascq = sense[13]; 408 409 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 410 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 411 412 /* Correct pc->xferred by asking the tape. */ 413 if (pc->flags & PC_FLAG_DMA_ERROR) { 414 pc->xferred = pc->req_xfer - 415 tape->blk_size * 416 get_unaligned_be32(&sense[3]); 417 idetape_update_buffers(drive, pc); 418 } 419 420 /* 421 * If error was the result of a zero-length read or write command, 422 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 423 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 424 */ 425 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 426 /* length == 0 */ 427 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 428 if (tape->sense_key == 5) { 429 /* don't report an error, everything's ok */ 430 pc->error = 0; 431 /* don't retry read/write */ 432 pc->flags |= PC_FLAG_ABORT; 433 } 434 } 435 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 436 pc->error = IDETAPE_ERROR_FILEMARK; 437 pc->flags |= PC_FLAG_ABORT; 438 } 439 if (pc->c[0] == WRITE_6) { 440 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 441 && tape->asc == 0x0 && tape->ascq == 0x2)) { 442 pc->error = IDETAPE_ERROR_EOD; 443 pc->flags |= PC_FLAG_ABORT; 444 } 445 } 446 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 447 if (tape->sense_key == 8) { 448 pc->error = IDETAPE_ERROR_EOD; 449 pc->flags |= PC_FLAG_ABORT; 450 } 451 if (!(pc->flags & PC_FLAG_ABORT) && 452 pc->xferred) 453 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 454 } 455} 456 457/* Free data buffers completely. */ 458static void ide_tape_kfree_buffer(idetape_tape_t *tape) 459{ 460 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 461 462 while (bh) { 463 u32 size = bh->b_size; 464 465 while (size) { 466 unsigned int order = fls(size >> PAGE_SHIFT)-1; 467 468 if (bh->b_data) 469 free_pages((unsigned long)bh->b_data, order); 470 471 size &= (order-1); 472 bh->b_data += (1 << order) * PAGE_SIZE; 473 } 474 prev_bh = bh; 475 bh = bh->b_reqnext; 476 kfree(prev_bh); 477 } 478} 479 480static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 481{ 482 struct request *rq = HWGROUP(drive)->rq; 483 idetape_tape_t *tape = drive->driver_data; 484 unsigned long flags; 485 int error; 486 487 debug_log(DBG_PROCS, "Enter %s\n", __func__); 488 489 switch (uptodate) { 490 case 0: error = IDETAPE_ERROR_GENERAL; break; 491 case 1: error = 0; break; 492 default: error = uptodate; 493 } 494 rq->errors = error; 495 if (error) 496 tape->failed_pc = NULL; 497 498 if (!blk_special_request(rq)) { 499 ide_end_request(drive, uptodate, nr_sects); 500 return 0; 501 } 502 503 spin_lock_irqsave(&tape->lock, flags); 504 505 ide_end_drive_cmd(drive, 0, 0); 506 507 spin_unlock_irqrestore(&tape->lock, flags); 508 return 0; 509} 510 511static void ide_tape_handle_dsc(ide_drive_t *); 512 513static void ide_tape_callback(ide_drive_t *drive, int dsc) 514{ 515 idetape_tape_t *tape = drive->driver_data; 516 struct ide_atapi_pc *pc = drive->pc; 517 int uptodate = pc->error ? 0 : 1; 518 519 debug_log(DBG_PROCS, "Enter %s\n", __func__); 520 521 if (dsc) 522 ide_tape_handle_dsc(drive); 523 524 if (tape->failed_pc == pc) 525 tape->failed_pc = NULL; 526 527 if (pc->c[0] == REQUEST_SENSE) { 528 if (uptodate) 529 idetape_analyze_error(drive, pc->buf); 530 else 531 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 532 "itself - Aborting request!\n"); 533 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 534 struct request *rq = drive->hwif->hwgroup->rq; 535 int blocks = pc->xferred / tape->blk_size; 536 537 tape->avg_size += blocks * tape->blk_size; 538 539 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 540 tape->avg_speed = tape->avg_size * HZ / 541 (jiffies - tape->avg_time) / 1024; 542 tape->avg_size = 0; 543 tape->avg_time = jiffies; 544 } 545 546 tape->first_frame += blocks; 547 rq->current_nr_sectors -= blocks; 548 549 if (pc->error) 550 uptodate = pc->error; 551 } else if (pc->c[0] == READ_POSITION && uptodate) { 552 u8 *readpos = pc->buf; 553 554 debug_log(DBG_SENSE, "BOP - %s\n", 555 (readpos[0] & 0x80) ? "Yes" : "No"); 556 debug_log(DBG_SENSE, "EOP - %s\n", 557 (readpos[0] & 0x40) ? "Yes" : "No"); 558 559 if (readpos[0] & 0x4) { 560 printk(KERN_INFO "ide-tape: Block location is unknown" 561 "to the tape\n"); 562 clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 563 uptodate = 0; 564 } else { 565 debug_log(DBG_SENSE, "Block Location - %u\n", 566 be32_to_cpup((__be32 *)&readpos[4])); 567 568 tape->partition = readpos[1]; 569 tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]); 570 set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 571 } 572 } 573 574 idetape_end_request(drive, uptodate, 0); 575} 576 577/* 578 * Postpone the current request so that ide.c will be able to service requests 579 * from another device on the same hwgroup while we are polling for DSC. 580 */ 581static void idetape_postpone_request(ide_drive_t *drive) 582{ 583 idetape_tape_t *tape = drive->driver_data; 584 585 debug_log(DBG_PROCS, "Enter %s\n", __func__); 586 587 tape->postponed_rq = HWGROUP(drive)->rq; 588 ide_stall_queue(drive, tape->dsc_poll_freq); 589} 590 591static void ide_tape_handle_dsc(ide_drive_t *drive) 592{ 593 idetape_tape_t *tape = drive->driver_data; 594 595 /* Media access command */ 596 tape->dsc_polling_start = jiffies; 597 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 598 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 599 /* Allow ide.c to handle other requests */ 600 idetape_postpone_request(drive); 601} 602 603static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 604 unsigned int bcount, int write) 605{ 606 if (write) 607 idetape_output_buffers(drive, pc, bcount); 608 else 609 idetape_input_buffers(drive, pc, bcount); 610 611 return bcount; 612} 613 614/* 615 * Packet Command Interface 616 * 617 * The current Packet Command is available in drive->pc, and will not change 618 * until we finish handling it. Each packet command is associated with a 619 * callback function that will be called when the command is finished. 620 * 621 * The handling will be done in three stages: 622 * 623 * 1. idetape_issue_pc will send the packet command to the drive, and will set 624 * the interrupt handler to ide_pc_intr. 625 * 626 * 2. On each interrupt, ide_pc_intr will be called. This step will be 627 * repeated until the device signals us that no more interrupts will be issued. 628 * 629 * 3. ATAPI Tape media access commands have immediate status with a delayed 630 * process. In case of a successful initiation of a media access packet command, 631 * the DSC bit will be set when the actual execution of the command is finished. 632 * Since the tape drive will not issue an interrupt, we have to poll for this 633 * event. In this case, we define the request as "low priority request" by 634 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 635 * exit the driver. 636 * 637 * ide.c will then give higher priority to requests which originate from the 638 * other device, until will change rq_status to RQ_ACTIVE. 639 * 640 * 4. When the packet command is finished, it will be checked for errors. 641 * 642 * 5. In case an error was found, we queue a request sense packet command in 643 * front of the request queue and retry the operation up to 644 * IDETAPE_MAX_PC_RETRIES times. 645 * 646 * 6. In case no error was found, or we decided to give up and not to retry 647 * again, the callback function will be called and then we will handle the next 648 * request. 649 */ 650 651static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 652 struct ide_atapi_pc *pc) 653{ 654 idetape_tape_t *tape = drive->driver_data; 655 656 if (drive->pc->c[0] == REQUEST_SENSE && 657 pc->c[0] == REQUEST_SENSE) { 658 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 659 "Two request sense in serial were issued\n"); 660 } 661 662 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 663 tape->failed_pc = pc; 664 665 /* Set the current packet command */ 666 drive->pc = pc; 667 668 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 669 (pc->flags & PC_FLAG_ABORT)) { 670 /* 671 * We will "abort" retrying a packet command in case legitimate 672 * error code was received (crossing a filemark, or end of the 673 * media, for example). 674 */ 675 if (!(pc->flags & PC_FLAG_ABORT)) { 676 if (!(pc->c[0] == TEST_UNIT_READY && 677 tape->sense_key == 2 && tape->asc == 4 && 678 (tape->ascq == 1 || tape->ascq == 8))) { 679 printk(KERN_ERR "ide-tape: %s: I/O error, " 680 "pc = %2x, key = %2x, " 681 "asc = %2x, ascq = %2x\n", 682 tape->name, pc->c[0], 683 tape->sense_key, tape->asc, 684 tape->ascq); 685 } 686 /* Giving up */ 687 pc->error = IDETAPE_ERROR_GENERAL; 688 } 689 tape->failed_pc = NULL; 690 drive->pc_callback(drive, 0); 691 return ide_stopped; 692 } 693 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 694 695 pc->retries++; 696 697 return ide_issue_pc(drive, WAIT_TAPE_CMD, NULL); 698} 699 700/* A mode sense command is used to "sense" tape parameters. */ 701static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 702{ 703 ide_init_pc(pc); 704 pc->c[0] = MODE_SENSE; 705 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 706 /* DBD = 1 - Don't return block descriptors */ 707 pc->c[1] = 8; 708 pc->c[2] = page_code; 709 /* 710 * Changed pc->c[3] to 0 (255 will at best return unused info). 711 * 712 * For SCSI this byte is defined as subpage instead of high byte 713 * of length and some IDE drives seem to interpret it this way 714 * and return an error when 255 is used. 715 */ 716 pc->c[3] = 0; 717 /* We will just discard data in that case */ 718 pc->c[4] = 255; 719 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 720 pc->req_xfer = 12; 721 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 722 pc->req_xfer = 24; 723 else 724 pc->req_xfer = 50; 725} 726 727static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 728{ 729 ide_hwif_t *hwif = drive->hwif; 730 idetape_tape_t *tape = drive->driver_data; 731 struct ide_atapi_pc *pc = drive->pc; 732 u8 stat; 733 734 stat = hwif->tp_ops->read_status(hwif); 735 736 if (stat & ATA_DSC) { 737 if (stat & ATA_ERR) { 738 /* Error detected */ 739 if (pc->c[0] != TEST_UNIT_READY) 740 printk(KERN_ERR "ide-tape: %s: I/O error, ", 741 tape->name); 742 /* Retry operation */ 743 ide_retry_pc(drive, tape->disk); 744 return ide_stopped; 745 } 746 pc->error = 0; 747 } else { 748 pc->error = IDETAPE_ERROR_GENERAL; 749 tape->failed_pc = NULL; 750 } 751 drive->pc_callback(drive, 0); 752 return ide_stopped; 753} 754 755static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 756 struct ide_atapi_pc *pc, struct request *rq, 757 u8 opcode) 758{ 759 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 760 unsigned int length = rq->current_nr_sectors; 761 762 ide_init_pc(pc); 763 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 764 pc->c[1] = 1; 765 pc->bh = bh; 766 pc->buf = NULL; 767 pc->buf_size = length * tape->blk_size; 768 pc->req_xfer = pc->buf_size; 769 if (pc->req_xfer == tape->buffer_size) 770 pc->flags |= PC_FLAG_DMA_OK; 771 772 if (opcode == READ_6) { 773 pc->c[0] = READ_6; 774 atomic_set(&bh->b_count, 0); 775 } else if (opcode == WRITE_6) { 776 pc->c[0] = WRITE_6; 777 pc->flags |= PC_FLAG_WRITING; 778 pc->b_data = bh->b_data; 779 pc->b_count = atomic_read(&bh->b_count); 780 } 781 782 memcpy(rq->cmd, pc->c, 12); 783} 784 785static ide_startstop_t idetape_do_request(ide_drive_t *drive, 786 struct request *rq, sector_t block) 787{ 788 ide_hwif_t *hwif = drive->hwif; 789 idetape_tape_t *tape = drive->driver_data; 790 struct ide_atapi_pc *pc = NULL; 791 struct request *postponed_rq = tape->postponed_rq; 792 u8 stat; 793 794 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 795 " current_nr_sectors: %u\n", 796 (unsigned long long)rq->sector, rq->nr_sectors, 797 rq->current_nr_sectors); 798 799 if (!blk_special_request(rq)) { 800 /* We do not support buffer cache originated requests. */ 801 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 802 "request queue (%d)\n", drive->name, rq->cmd_type); 803 ide_end_request(drive, 0, 0); 804 return ide_stopped; 805 } 806 807 /* Retry a failed packet command */ 808 if (tape->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { 809 pc = tape->failed_pc; 810 goto out; 811 } 812 813 if (postponed_rq != NULL) 814 if (rq != postponed_rq) { 815 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 816 "Two DSC requests were queued\n"); 817 idetape_end_request(drive, 0, 0); 818 return ide_stopped; 819 } 820 821 tape->postponed_rq = NULL; 822 823 /* 824 * If the tape is still busy, postpone our request and service 825 * the other device meanwhile. 826 */ 827 stat = hwif->tp_ops->read_status(hwif); 828 829 if (!drive->dsc_overlap && !(rq->cmd[13] & REQ_IDETAPE_PC2)) 830 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 831 832 if (drive->post_reset == 1) { 833 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 834 drive->post_reset = 0; 835 } 836 837 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 838 (stat & ATA_DSC) == 0) { 839 if (postponed_rq == NULL) { 840 tape->dsc_polling_start = jiffies; 841 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 842 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 843 } else if (time_after(jiffies, tape->dsc_timeout)) { 844 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 845 tape->name); 846 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 847 idetape_media_access_finished(drive); 848 return ide_stopped; 849 } else { 850 return ide_do_reset(drive); 851 } 852 } else if (time_after(jiffies, 853 tape->dsc_polling_start + 854 IDETAPE_DSC_MA_THRESHOLD)) 855 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 856 idetape_postpone_request(drive); 857 return ide_stopped; 858 } 859 if (rq->cmd[13] & REQ_IDETAPE_READ) { 860 pc = &tape->queued_pc; 861 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 862 goto out; 863 } 864 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 865 pc = &tape->queued_pc; 866 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 867 goto out; 868 } 869 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 870 pc = (struct ide_atapi_pc *) rq->buffer; 871 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 872 rq->cmd[13] |= REQ_IDETAPE_PC2; 873 goto out; 874 } 875 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 876 idetape_media_access_finished(drive); 877 return ide_stopped; 878 } 879 BUG(); 880 881out: 882 return idetape_issue_pc(drive, pc); 883} 884 885/* 886 * The function below uses __get_free_pages to allocate a data buffer of size 887 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 888 * much as possible. 889 * 890 * It returns a pointer to the newly allocated buffer, or NULL in case of 891 * failure. 892 */ 893static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 894 int full, int clear) 895{ 896 struct idetape_bh *prev_bh, *bh, *merge_bh; 897 int pages = tape->pages_per_buffer; 898 unsigned int order, b_allocd; 899 char *b_data = NULL; 900 901 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 902 bh = merge_bh; 903 if (bh == NULL) 904 goto abort; 905 906 order = fls(pages) - 1; 907 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 908 if (!bh->b_data) 909 goto abort; 910 b_allocd = (1 << order) * PAGE_SIZE; 911 pages &= (order-1); 912 913 if (clear) 914 memset(bh->b_data, 0, b_allocd); 915 bh->b_reqnext = NULL; 916 bh->b_size = b_allocd; 917 atomic_set(&bh->b_count, full ? bh->b_size : 0); 918 919 while (pages) { 920 order = fls(pages) - 1; 921 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 922 if (!b_data) 923 goto abort; 924 b_allocd = (1 << order) * PAGE_SIZE; 925 926 if (clear) 927 memset(b_data, 0, b_allocd); 928 929 /* newly allocated page frames below buffer header or ...*/ 930 if (bh->b_data == b_data + b_allocd) { 931 bh->b_size += b_allocd; 932 bh->b_data -= b_allocd; 933 if (full) 934 atomic_add(b_allocd, &bh->b_count); 935 continue; 936 } 937 /* they are above the header */ 938 if (b_data == bh->b_data + bh->b_size) { 939 bh->b_size += b_allocd; 940 if (full) 941 atomic_add(b_allocd, &bh->b_count); 942 continue; 943 } 944 prev_bh = bh; 945 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 946 if (!bh) { 947 free_pages((unsigned long) b_data, order); 948 goto abort; 949 } 950 bh->b_reqnext = NULL; 951 bh->b_data = b_data; 952 bh->b_size = b_allocd; 953 atomic_set(&bh->b_count, full ? bh->b_size : 0); 954 prev_bh->b_reqnext = bh; 955 956 pages &= (order-1); 957 } 958 959 bh->b_size -= tape->excess_bh_size; 960 if (full) 961 atomic_sub(tape->excess_bh_size, &bh->b_count); 962 return merge_bh; 963abort: 964 ide_tape_kfree_buffer(tape); 965 return NULL; 966} 967 968static int idetape_copy_stage_from_user(idetape_tape_t *tape, 969 const char __user *buf, int n) 970{ 971 struct idetape_bh *bh = tape->bh; 972 int count; 973 int ret = 0; 974 975 while (n) { 976 if (bh == NULL) { 977 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 978 __func__); 979 return 1; 980 } 981 count = min((unsigned int) 982 (bh->b_size - atomic_read(&bh->b_count)), 983 (unsigned int)n); 984 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 985 count)) 986 ret = 1; 987 n -= count; 988 atomic_add(count, &bh->b_count); 989 buf += count; 990 if (atomic_read(&bh->b_count) == bh->b_size) { 991 bh = bh->b_reqnext; 992 if (bh) 993 atomic_set(&bh->b_count, 0); 994 } 995 } 996 tape->bh = bh; 997 return ret; 998} 999 1000static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1001 int n) 1002{ 1003 struct idetape_bh *bh = tape->bh; 1004 int count; 1005 int ret = 0; 1006 1007 while (n) { 1008 if (bh == NULL) { 1009 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1010 __func__); 1011 return 1; 1012 } 1013 count = min(tape->b_count, n); 1014 if (copy_to_user(buf, tape->b_data, count)) 1015 ret = 1; 1016 n -= count; 1017 tape->b_data += count; 1018 tape->b_count -= count; 1019 buf += count; 1020 if (!tape->b_count) { 1021 bh = bh->b_reqnext; 1022 tape->bh = bh; 1023 if (bh) { 1024 tape->b_data = bh->b_data; 1025 tape->b_count = atomic_read(&bh->b_count); 1026 } 1027 } 1028 } 1029 return ret; 1030} 1031 1032static void idetape_init_merge_buffer(idetape_tape_t *tape) 1033{ 1034 struct idetape_bh *bh = tape->merge_bh; 1035 tape->bh = tape->merge_bh; 1036 1037 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1038 atomic_set(&bh->b_count, 0); 1039 else { 1040 tape->b_data = bh->b_data; 1041 tape->b_count = atomic_read(&bh->b_count); 1042 } 1043} 1044 1045/* 1046 * Write a filemark if write_filemark=1. Flush the device buffers without 1047 * writing a filemark otherwise. 1048 */ 1049static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1050 struct ide_atapi_pc *pc, int write_filemark) 1051{ 1052 ide_init_pc(pc); 1053 pc->c[0] = WRITE_FILEMARKS; 1054 pc->c[4] = write_filemark; 1055 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1056} 1057 1058static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1059{ 1060 idetape_tape_t *tape = drive->driver_data; 1061 struct gendisk *disk = tape->disk; 1062 int load_attempted = 0; 1063 1064 /* Wait for the tape to become ready */ 1065 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1066 timeout += jiffies; 1067 while (time_before(jiffies, timeout)) { 1068 if (ide_do_test_unit_ready(drive, disk) == 0) 1069 return 0; 1070 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1071 || (tape->asc == 0x3A)) { 1072 /* no media */ 1073 if (load_attempted) 1074 return -ENOMEDIUM; 1075 ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1076 load_attempted = 1; 1077 /* not about to be ready */ 1078 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1079 (tape->ascq == 1 || tape->ascq == 8))) 1080 return -EIO; 1081 msleep(100); 1082 } 1083 return -EIO; 1084} 1085 1086static int idetape_flush_tape_buffers(ide_drive_t *drive) 1087{ 1088 struct ide_tape_obj *tape = drive->driver_data; 1089 struct ide_atapi_pc pc; 1090 int rc; 1091 1092 idetape_create_write_filemark_cmd(drive, &pc, 0); 1093 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1094 if (rc) 1095 return rc; 1096 idetape_wait_ready(drive, 60 * 5 * HZ); 1097 return 0; 1098} 1099 1100static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1101{ 1102 ide_init_pc(pc); 1103 pc->c[0] = READ_POSITION; 1104 pc->req_xfer = 20; 1105} 1106 1107static int idetape_read_position(ide_drive_t *drive) 1108{ 1109 idetape_tape_t *tape = drive->driver_data; 1110 struct ide_atapi_pc pc; 1111 int position; 1112 1113 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1114 1115 idetape_create_read_position_cmd(&pc); 1116 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1117 return -1; 1118 position = tape->first_frame; 1119 return position; 1120} 1121 1122static void idetape_create_locate_cmd(ide_drive_t *drive, 1123 struct ide_atapi_pc *pc, 1124 unsigned int block, u8 partition, int skip) 1125{ 1126 ide_init_pc(pc); 1127 pc->c[0] = POSITION_TO_ELEMENT; 1128 pc->c[1] = 2; 1129 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1130 pc->c[8] = partition; 1131 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1132} 1133 1134static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1135{ 1136 idetape_tape_t *tape = drive->driver_data; 1137 1138 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1139 return; 1140 1141 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1142 tape->merge_bh_size = 0; 1143 if (tape->merge_bh != NULL) { 1144 ide_tape_kfree_buffer(tape); 1145 tape->merge_bh = NULL; 1146 } 1147 1148 tape->chrdev_dir = IDETAPE_DIR_NONE; 1149} 1150 1151/* 1152 * Position the tape to the requested block using the LOCATE packet command. 1153 * A READ POSITION command is then issued to check where we are positioned. Like 1154 * all higher level operations, we queue the commands at the tail of the request 1155 * queue and wait for their completion. 1156 */ 1157static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1158 u8 partition, int skip) 1159{ 1160 idetape_tape_t *tape = drive->driver_data; 1161 struct gendisk *disk = tape->disk; 1162 int retval; 1163 struct ide_atapi_pc pc; 1164 1165 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1166 __ide_tape_discard_merge_buffer(drive); 1167 idetape_wait_ready(drive, 60 * 5 * HZ); 1168 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1169 retval = ide_queue_pc_tail(drive, disk, &pc); 1170 if (retval) 1171 return (retval); 1172 1173 idetape_create_read_position_cmd(&pc); 1174 return ide_queue_pc_tail(drive, disk, &pc); 1175} 1176 1177static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1178 int restore_position) 1179{ 1180 idetape_tape_t *tape = drive->driver_data; 1181 int seek, position; 1182 1183 __ide_tape_discard_merge_buffer(drive); 1184 if (restore_position) { 1185 position = idetape_read_position(drive); 1186 seek = position > 0 ? position : 0; 1187 if (idetape_position_tape(drive, seek, 0, 0)) { 1188 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1189 " %s\n", tape->name, __func__); 1190 return; 1191 } 1192 } 1193} 1194 1195/* 1196 * Generate a read/write request for the block device interface and wait for it 1197 * to be serviced. 1198 */ 1199static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1200 struct idetape_bh *bh) 1201{ 1202 idetape_tape_t *tape = drive->driver_data; 1203 struct request *rq; 1204 int ret, errors; 1205 1206 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1207 1208 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1209 rq->cmd_type = REQ_TYPE_SPECIAL; 1210 rq->cmd[13] = cmd; 1211 rq->rq_disk = tape->disk; 1212 rq->special = (void *)bh; 1213 rq->sector = tape->first_frame; 1214 rq->nr_sectors = blocks; 1215 rq->current_nr_sectors = blocks; 1216 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1217 1218 errors = rq->errors; 1219 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1220 blk_put_request(rq); 1221 1222 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1223 return 0; 1224 1225 if (tape->merge_bh) 1226 idetape_init_merge_buffer(tape); 1227 if (errors == IDETAPE_ERROR_GENERAL) 1228 return -EIO; 1229 return ret; 1230} 1231 1232static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1233{ 1234 ide_init_pc(pc); 1235 pc->c[0] = INQUIRY; 1236 pc->c[4] = 254; 1237 pc->req_xfer = 254; 1238} 1239 1240static void idetape_create_rewind_cmd(ide_drive_t *drive, 1241 struct ide_atapi_pc *pc) 1242{ 1243 ide_init_pc(pc); 1244 pc->c[0] = REZERO_UNIT; 1245 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1246} 1247 1248static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1249{ 1250 ide_init_pc(pc); 1251 pc->c[0] = ERASE; 1252 pc->c[1] = 1; 1253 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1254} 1255 1256static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1257{ 1258 ide_init_pc(pc); 1259 pc->c[0] = SPACE; 1260 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1261 pc->c[1] = cmd; 1262 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1263} 1264 1265/* Queue up a character device originated write request. */ 1266static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1267{ 1268 idetape_tape_t *tape = drive->driver_data; 1269 1270 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1271 1272 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1273 blocks, tape->merge_bh); 1274} 1275 1276static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1277{ 1278 idetape_tape_t *tape = drive->driver_data; 1279 int blocks, min; 1280 struct idetape_bh *bh; 1281 1282 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1283 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1284 " but we are not writing.\n"); 1285 return; 1286 } 1287 if (tape->merge_bh_size > tape->buffer_size) { 1288 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1289 tape->merge_bh_size = tape->buffer_size; 1290 } 1291 if (tape->merge_bh_size) { 1292 blocks = tape->merge_bh_size / tape->blk_size; 1293 if (tape->merge_bh_size % tape->blk_size) { 1294 unsigned int i; 1295 1296 blocks++; 1297 i = tape->blk_size - tape->merge_bh_size % 1298 tape->blk_size; 1299 bh = tape->bh->b_reqnext; 1300 while (bh) { 1301 atomic_set(&bh->b_count, 0); 1302 bh = bh->b_reqnext; 1303 } 1304 bh = tape->bh; 1305 while (i) { 1306 if (bh == NULL) { 1307 printk(KERN_INFO "ide-tape: bug," 1308 " bh NULL\n"); 1309 break; 1310 } 1311 min = min(i, (unsigned int)(bh->b_size - 1312 atomic_read(&bh->b_count))); 1313 memset(bh->b_data + atomic_read(&bh->b_count), 1314 0, min); 1315 atomic_add(min, &bh->b_count); 1316 i -= min; 1317 bh = bh->b_reqnext; 1318 } 1319 } 1320 (void) idetape_add_chrdev_write_request(drive, blocks); 1321 tape->merge_bh_size = 0; 1322 } 1323 if (tape->merge_bh != NULL) { 1324 ide_tape_kfree_buffer(tape); 1325 tape->merge_bh = NULL; 1326 } 1327 tape->chrdev_dir = IDETAPE_DIR_NONE; 1328} 1329 1330static int idetape_init_read(ide_drive_t *drive) 1331{ 1332 idetape_tape_t *tape = drive->driver_data; 1333 int bytes_read; 1334 1335 /* Initialize read operation */ 1336 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1337 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1338 ide_tape_flush_merge_buffer(drive); 1339 idetape_flush_tape_buffers(drive); 1340 } 1341 if (tape->merge_bh || tape->merge_bh_size) { 1342 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1343 " 0 now\n"); 1344 tape->merge_bh_size = 0; 1345 } 1346 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1347 if (!tape->merge_bh) 1348 return -ENOMEM; 1349 tape->chrdev_dir = IDETAPE_DIR_READ; 1350 1351 /* 1352 * Issue a read 0 command to ensure that DSC handshake is 1353 * switched from completion mode to buffer available mode. 1354 * No point in issuing this if DSC overlap isn't supported, some 1355 * drives (Seagate STT3401A) will return an error. 1356 */ 1357 if (drive->dsc_overlap) { 1358 bytes_read = idetape_queue_rw_tail(drive, 1359 REQ_IDETAPE_READ, 0, 1360 tape->merge_bh); 1361 if (bytes_read < 0) { 1362 ide_tape_kfree_buffer(tape); 1363 tape->merge_bh = NULL; 1364 tape->chrdev_dir = IDETAPE_DIR_NONE; 1365 return bytes_read; 1366 } 1367 } 1368 } 1369 1370 return 0; 1371} 1372 1373/* called from idetape_chrdev_read() to service a chrdev read request. */ 1374static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1375{ 1376 idetape_tape_t *tape = drive->driver_data; 1377 1378 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1379 1380 /* If we are at a filemark, return a read length of 0 */ 1381 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1382 return 0; 1383 1384 idetape_init_read(drive); 1385 1386 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1387 tape->merge_bh); 1388} 1389 1390static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1391{ 1392 idetape_tape_t *tape = drive->driver_data; 1393 struct idetape_bh *bh; 1394 int blocks; 1395 1396 while (bcount) { 1397 unsigned int count; 1398 1399 bh = tape->merge_bh; 1400 count = min(tape->buffer_size, bcount); 1401 bcount -= count; 1402 blocks = count / tape->blk_size; 1403 while (count) { 1404 atomic_set(&bh->b_count, 1405 min(count, (unsigned int)bh->b_size)); 1406 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1407 count -= atomic_read(&bh->b_count); 1408 bh = bh->b_reqnext; 1409 } 1410 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1411 tape->merge_bh); 1412 } 1413} 1414 1415/* 1416 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1417 * currently support only one partition. 1418 */ 1419static int idetape_rewind_tape(ide_drive_t *drive) 1420{ 1421 struct ide_tape_obj *tape = drive->driver_data; 1422 struct gendisk *disk = tape->disk; 1423 int retval; 1424 struct ide_atapi_pc pc; 1425 1426 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1427 1428 idetape_create_rewind_cmd(drive, &pc); 1429 retval = ide_queue_pc_tail(drive, disk, &pc); 1430 if (retval) 1431 return retval; 1432 1433 idetape_create_read_position_cmd(&pc); 1434 retval = ide_queue_pc_tail(drive, disk, &pc); 1435 if (retval) 1436 return retval; 1437 return 0; 1438} 1439 1440/* mtio.h compatible commands should be issued to the chrdev interface. */ 1441static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1442 unsigned long arg) 1443{ 1444 idetape_tape_t *tape = drive->driver_data; 1445 void __user *argp = (void __user *)arg; 1446 1447 struct idetape_config { 1448 int dsc_rw_frequency; 1449 int dsc_media_access_frequency; 1450 int nr_stages; 1451 } config; 1452 1453 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1454 1455 switch (cmd) { 1456 case 0x0340: 1457 if (copy_from_user(&config, argp, sizeof(config))) 1458 return -EFAULT; 1459 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1460 break; 1461 case 0x0350: 1462 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1463 config.nr_stages = 1; 1464 if (copy_to_user(argp, &config, sizeof(config))) 1465 return -EFAULT; 1466 break; 1467 default: 1468 return -EIO; 1469 } 1470 return 0; 1471} 1472 1473static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1474 int mt_count) 1475{ 1476 idetape_tape_t *tape = drive->driver_data; 1477 struct gendisk *disk = tape->disk; 1478 struct ide_atapi_pc pc; 1479 int retval, count = 0; 1480 int sprev = !!(tape->caps[4] & 0x20); 1481 1482 if (mt_count == 0) 1483 return 0; 1484 if (MTBSF == mt_op || MTBSFM == mt_op) { 1485 if (!sprev) 1486 return -EIO; 1487 mt_count = -mt_count; 1488 } 1489 1490 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1491 tape->merge_bh_size = 0; 1492 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1493 ++count; 1494 ide_tape_discard_merge_buffer(drive, 0); 1495 } 1496 1497 switch (mt_op) { 1498 case MTFSF: 1499 case MTBSF: 1500 idetape_create_space_cmd(&pc, mt_count - count, 1501 IDETAPE_SPACE_OVER_FILEMARK); 1502 return ide_queue_pc_tail(drive, disk, &pc); 1503 case MTFSFM: 1504 case MTBSFM: 1505 if (!sprev) 1506 return -EIO; 1507 retval = idetape_space_over_filemarks(drive, MTFSF, 1508 mt_count - count); 1509 if (retval) 1510 return retval; 1511 count = (MTBSFM == mt_op ? 1 : -1); 1512 return idetape_space_over_filemarks(drive, MTFSF, count); 1513 default: 1514 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1515 mt_op); 1516 return -EIO; 1517 } 1518} 1519 1520/* 1521 * Our character device read / write functions. 1522 * 1523 * The tape is optimized to maximize throughput when it is transferring an 1524 * integral number of the "continuous transfer limit", which is a parameter of 1525 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1526 * 1527 * As of version 1.3 of the driver, the character device provides an abstract 1528 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1529 * same backup/restore procedure is supported. The driver will internally 1530 * convert the requests to the recommended transfer unit, so that an unmatch 1531 * between the user's block size to the recommended size will only result in a 1532 * (slightly) increased driver overhead, but will no longer hit performance. 1533 * This is not applicable to Onstream. 1534 */ 1535static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1536 size_t count, loff_t *ppos) 1537{ 1538 struct ide_tape_obj *tape = file->private_data; 1539 ide_drive_t *drive = tape->drive; 1540 ssize_t bytes_read, temp, actually_read = 0, rc; 1541 ssize_t ret = 0; 1542 u16 ctl = *(u16 *)&tape->caps[12]; 1543 1544 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1545 1546 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1547 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1548 if (count > tape->blk_size && 1549 (count % tape->blk_size) == 0) 1550 tape->user_bs_factor = count / tape->blk_size; 1551 } 1552 rc = idetape_init_read(drive); 1553 if (rc < 0) 1554 return rc; 1555 if (count == 0) 1556 return (0); 1557 if (tape->merge_bh_size) { 1558 actually_read = min((unsigned int)(tape->merge_bh_size), 1559 (unsigned int)count); 1560 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1561 ret = -EFAULT; 1562 buf += actually_read; 1563 tape->merge_bh_size -= actually_read; 1564 count -= actually_read; 1565 } 1566 while (count >= tape->buffer_size) { 1567 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1568 if (bytes_read <= 0) 1569 goto finish; 1570 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1571 ret = -EFAULT; 1572 buf += bytes_read; 1573 count -= bytes_read; 1574 actually_read += bytes_read; 1575 } 1576 if (count) { 1577 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1578 if (bytes_read <= 0) 1579 goto finish; 1580 temp = min((unsigned long)count, (unsigned long)bytes_read); 1581 if (idetape_copy_stage_to_user(tape, buf, temp)) 1582 ret = -EFAULT; 1583 actually_read += temp; 1584 tape->merge_bh_size = bytes_read-temp; 1585 } 1586finish: 1587 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1588 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1589 1590 idetape_space_over_filemarks(drive, MTFSF, 1); 1591 return 0; 1592 } 1593 1594 return ret ? ret : actually_read; 1595} 1596 1597static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1598 size_t count, loff_t *ppos) 1599{ 1600 struct ide_tape_obj *tape = file->private_data; 1601 ide_drive_t *drive = tape->drive; 1602 ssize_t actually_written = 0; 1603 ssize_t ret = 0; 1604 u16 ctl = *(u16 *)&tape->caps[12]; 1605 1606 /* The drive is write protected. */ 1607 if (tape->write_prot) 1608 return -EACCES; 1609 1610 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1611 1612 /* Initialize write operation */ 1613 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1614 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1615 ide_tape_discard_merge_buffer(drive, 1); 1616 if (tape->merge_bh || tape->merge_bh_size) { 1617 printk(KERN_ERR "ide-tape: merge_bh_size " 1618 "should be 0 now\n"); 1619 tape->merge_bh_size = 0; 1620 } 1621 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1622 if (!tape->merge_bh) 1623 return -ENOMEM; 1624 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1625 idetape_init_merge_buffer(tape); 1626 1627 /* 1628 * Issue a write 0 command to ensure that DSC handshake is 1629 * switched from completion mode to buffer available mode. No 1630 * point in issuing this if DSC overlap isn't supported, some 1631 * drives (Seagate STT3401A) will return an error. 1632 */ 1633 if (drive->dsc_overlap) { 1634 ssize_t retval = idetape_queue_rw_tail(drive, 1635 REQ_IDETAPE_WRITE, 0, 1636 tape->merge_bh); 1637 if (retval < 0) { 1638 ide_tape_kfree_buffer(tape); 1639 tape->merge_bh = NULL; 1640 tape->chrdev_dir = IDETAPE_DIR_NONE; 1641 return retval; 1642 } 1643 } 1644 } 1645 if (count == 0) 1646 return (0); 1647 if (tape->merge_bh_size) { 1648 if (tape->merge_bh_size >= tape->buffer_size) { 1649 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1650 tape->merge_bh_size = 0; 1651 } 1652 actually_written = min((unsigned int) 1653 (tape->buffer_size - tape->merge_bh_size), 1654 (unsigned int)count); 1655 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1656 ret = -EFAULT; 1657 buf += actually_written; 1658 tape->merge_bh_size += actually_written; 1659 count -= actually_written; 1660 1661 if (tape->merge_bh_size == tape->buffer_size) { 1662 ssize_t retval; 1663 tape->merge_bh_size = 0; 1664 retval = idetape_add_chrdev_write_request(drive, ctl); 1665 if (retval <= 0) 1666 return (retval); 1667 } 1668 } 1669 while (count >= tape->buffer_size) { 1670 ssize_t retval; 1671 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1672 ret = -EFAULT; 1673 buf += tape->buffer_size; 1674 count -= tape->buffer_size; 1675 retval = idetape_add_chrdev_write_request(drive, ctl); 1676 actually_written += tape->buffer_size; 1677 if (retval <= 0) 1678 return (retval); 1679 } 1680 if (count) { 1681 actually_written += count; 1682 if (idetape_copy_stage_from_user(tape, buf, count)) 1683 ret = -EFAULT; 1684 tape->merge_bh_size += count; 1685 } 1686 return ret ? ret : actually_written; 1687} 1688 1689static int idetape_write_filemark(ide_drive_t *drive) 1690{ 1691 struct ide_tape_obj *tape = drive->driver_data; 1692 struct ide_atapi_pc pc; 1693 1694 /* Write a filemark */ 1695 idetape_create_write_filemark_cmd(drive, &pc, 1); 1696 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1697 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1698 return -EIO; 1699 } 1700 return 0; 1701} 1702 1703/* 1704 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1705 * requested. 1706 * 1707 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1708 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1709 * usually not supported. 1710 * 1711 * The following commands are currently not supported: 1712 * 1713 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1714 * MT_ST_WRITE_THRESHOLD. 1715 */ 1716static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1717{ 1718 idetape_tape_t *tape = drive->driver_data; 1719 struct gendisk *disk = tape->disk; 1720 struct ide_atapi_pc pc; 1721 int i, retval; 1722 1723 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1724 mt_op, mt_count); 1725 1726 switch (mt_op) { 1727 case MTFSF: 1728 case MTFSFM: 1729 case MTBSF: 1730 case MTBSFM: 1731 if (!mt_count) 1732 return 0; 1733 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1734 default: 1735 break; 1736 } 1737 1738 switch (mt_op) { 1739 case MTWEOF: 1740 if (tape->write_prot) 1741 return -EACCES; 1742 ide_tape_discard_merge_buffer(drive, 1); 1743 for (i = 0; i < mt_count; i++) { 1744 retval = idetape_write_filemark(drive); 1745 if (retval) 1746 return retval; 1747 } 1748 return 0; 1749 case MTREW: 1750 ide_tape_discard_merge_buffer(drive, 0); 1751 if (idetape_rewind_tape(drive)) 1752 return -EIO; 1753 return 0; 1754 case MTLOAD: 1755 ide_tape_discard_merge_buffer(drive, 0); 1756 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1757 case MTUNLOAD: 1758 case MTOFFL: 1759 /* 1760 * If door is locked, attempt to unlock before 1761 * attempting to eject. 1762 */ 1763 if (tape->door_locked) { 1764 if (!ide_set_media_lock(drive, disk, 0)) 1765 tape->door_locked = DOOR_UNLOCKED; 1766 } 1767 ide_tape_discard_merge_buffer(drive, 0); 1768 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); 1769 if (!retval) 1770 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1771 return retval; 1772 case MTNOP: 1773 ide_tape_discard_merge_buffer(drive, 0); 1774 return idetape_flush_tape_buffers(drive); 1775 case MTRETEN: 1776 ide_tape_discard_merge_buffer(drive, 0); 1777 return ide_do_start_stop(drive, disk, 1778 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1779 case MTEOM: 1780 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1781 return ide_queue_pc_tail(drive, disk, &pc); 1782 case MTERASE: 1783 (void)idetape_rewind_tape(drive); 1784 idetape_create_erase_cmd(&pc); 1785 return ide_queue_pc_tail(drive, disk, &pc); 1786 case MTSETBLK: 1787 if (mt_count) { 1788 if (mt_count < tape->blk_size || 1789 mt_count % tape->blk_size) 1790 return -EIO; 1791 tape->user_bs_factor = mt_count / tape->blk_size; 1792 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1793 } else 1794 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1795 return 0; 1796 case MTSEEK: 1797 ide_tape_discard_merge_buffer(drive, 0); 1798 return idetape_position_tape(drive, 1799 mt_count * tape->user_bs_factor, tape->partition, 0); 1800 case MTSETPART: 1801 ide_tape_discard_merge_buffer(drive, 0); 1802 return idetape_position_tape(drive, 0, mt_count, 0); 1803 case MTFSR: 1804 case MTBSR: 1805 case MTLOCK: 1806 retval = ide_set_media_lock(drive, disk, 1); 1807 if (retval) 1808 return retval; 1809 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1810 return 0; 1811 case MTUNLOCK: 1812 retval = ide_set_media_lock(drive, disk, 0); 1813 if (retval) 1814 return retval; 1815 tape->door_locked = DOOR_UNLOCKED; 1816 return 0; 1817 default: 1818 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1819 mt_op); 1820 return -EIO; 1821 } 1822} 1823 1824/* 1825 * Our character device ioctls. General mtio.h magnetic io commands are 1826 * supported here, and not in the corresponding block interface. Our own 1827 * ide-tape ioctls are supported on both interfaces. 1828 */ 1829static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1830 unsigned int cmd, unsigned long arg) 1831{ 1832 struct ide_tape_obj *tape = file->private_data; 1833 ide_drive_t *drive = tape->drive; 1834 struct mtop mtop; 1835 struct mtget mtget; 1836 struct mtpos mtpos; 1837 int block_offset = 0, position = tape->first_frame; 1838 void __user *argp = (void __user *)arg; 1839 1840 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1841 1842 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1843 ide_tape_flush_merge_buffer(drive); 1844 idetape_flush_tape_buffers(drive); 1845 } 1846 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1847 block_offset = tape->merge_bh_size / 1848 (tape->blk_size * tape->user_bs_factor); 1849 position = idetape_read_position(drive); 1850 if (position < 0) 1851 return -EIO; 1852 } 1853 switch (cmd) { 1854 case MTIOCTOP: 1855 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1856 return -EFAULT; 1857 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1858 case MTIOCGET: 1859 memset(&mtget, 0, sizeof(struct mtget)); 1860 mtget.mt_type = MT_ISSCSI2; 1861 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1862 mtget.mt_dsreg = 1863 ((tape->blk_size * tape->user_bs_factor) 1864 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1865 1866 if (tape->drv_write_prot) 1867 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1868 1869 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1870 return -EFAULT; 1871 return 0; 1872 case MTIOCPOS: 1873 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1874 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1875 return -EFAULT; 1876 return 0; 1877 default: 1878 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1879 ide_tape_discard_merge_buffer(drive, 1); 1880 return idetape_blkdev_ioctl(drive, cmd, arg); 1881 } 1882} 1883 1884/* 1885 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1886 * block size with the reported value. 1887 */ 1888static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1889{ 1890 idetape_tape_t *tape = drive->driver_data; 1891 struct ide_atapi_pc pc; 1892 1893 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1894 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1895 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1896 if (tape->blk_size == 0) { 1897 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1898 "block size, assuming 32k\n"); 1899 tape->blk_size = 32768; 1900 } 1901 return; 1902 } 1903 tape->blk_size = (pc.buf[4 + 5] << 16) + 1904 (pc.buf[4 + 6] << 8) + 1905 pc.buf[4 + 7]; 1906 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1907} 1908 1909static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1910{ 1911 unsigned int minor = iminor(inode), i = minor & ~0xc0; 1912 ide_drive_t *drive; 1913 idetape_tape_t *tape; 1914 int retval; 1915 1916 if (i >= MAX_HWIFS * MAX_DRIVES) 1917 return -ENXIO; 1918 1919 lock_kernel(); 1920 tape = ide_tape_chrdev_get(i); 1921 if (!tape) { 1922 unlock_kernel(); 1923 return -ENXIO; 1924 } 1925 1926 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1927 1928 /* 1929 * We really want to do nonseekable_open(inode, filp); here, but some 1930 * versions of tar incorrectly call lseek on tapes and bail out if that 1931 * fails. So we disallow pread() and pwrite(), but permit lseeks. 1932 */ 1933 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 1934 1935 drive = tape->drive; 1936 1937 filp->private_data = tape; 1938 1939 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 1940 retval = -EBUSY; 1941 goto out_put_tape; 1942 } 1943 1944 retval = idetape_wait_ready(drive, 60 * HZ); 1945 if (retval) { 1946 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1947 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 1948 goto out_put_tape; 1949 } 1950 1951 idetape_read_position(drive); 1952 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 1953 (void)idetape_rewind_tape(drive); 1954 1955 /* Read block size and write protect status from drive. */ 1956 ide_tape_get_bsize_from_bdesc(drive); 1957 1958 /* Set write protect flag if device is opened as read-only. */ 1959 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 1960 tape->write_prot = 1; 1961 else 1962 tape->write_prot = tape->drv_write_prot; 1963 1964 /* Make sure drive isn't write protected if user wants to write. */ 1965 if (tape->write_prot) { 1966 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 1967 (filp->f_flags & O_ACCMODE) == O_RDWR) { 1968 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1969 retval = -EROFS; 1970 goto out_put_tape; 1971 } 1972 } 1973 1974 /* Lock the tape drive door so user can't eject. */ 1975 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1976 if (!ide_set_media_lock(drive, tape->disk, 1)) { 1977 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 1978 tape->door_locked = DOOR_LOCKED; 1979 } 1980 } 1981 unlock_kernel(); 1982 return 0; 1983 1984out_put_tape: 1985 ide_tape_put(tape); 1986 unlock_kernel(); 1987 return retval; 1988} 1989 1990static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 1991{ 1992 idetape_tape_t *tape = drive->driver_data; 1993 1994 ide_tape_flush_merge_buffer(drive); 1995 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 1996 if (tape->merge_bh != NULL) { 1997 idetape_pad_zeros(drive, tape->blk_size * 1998 (tape->user_bs_factor - 1)); 1999 ide_tape_kfree_buffer(tape); 2000 tape->merge_bh = NULL; 2001 } 2002 idetape_write_filemark(drive); 2003 idetape_flush_tape_buffers(drive); 2004 idetape_flush_tape_buffers(drive); 2005} 2006 2007static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2008{ 2009 struct ide_tape_obj *tape = filp->private_data; 2010 ide_drive_t *drive = tape->drive; 2011 unsigned int minor = iminor(inode); 2012 2013 lock_kernel(); 2014 tape = drive->driver_data; 2015 2016 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2017 2018 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2019 idetape_write_release(drive, minor); 2020 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2021 if (minor < 128) 2022 ide_tape_discard_merge_buffer(drive, 1); 2023 } 2024 2025 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 2026 (void) idetape_rewind_tape(drive); 2027 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2028 if (tape->door_locked == DOOR_LOCKED) { 2029 if (!ide_set_media_lock(drive, tape->disk, 0)) 2030 tape->door_locked = DOOR_UNLOCKED; 2031 } 2032 } 2033 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2034 ide_tape_put(tape); 2035 unlock_kernel(); 2036 return 0; 2037} 2038 2039static void idetape_get_inquiry_results(ide_drive_t *drive) 2040{ 2041 idetape_tape_t *tape = drive->driver_data; 2042 struct ide_atapi_pc pc; 2043 char fw_rev[4], vendor_id[8], product_id[16]; 2044 2045 idetape_create_inquiry_cmd(&pc); 2046 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2047 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2048 tape->name); 2049 return; 2050 } 2051 memcpy(vendor_id, &pc.buf[8], 8); 2052 memcpy(product_id, &pc.buf[16], 16); 2053 memcpy(fw_rev, &pc.buf[32], 4); 2054 2055 ide_fixstring(vendor_id, 8, 0); 2056 ide_fixstring(product_id, 16, 0); 2057 ide_fixstring(fw_rev, 4, 0); 2058 2059 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2060 drive->name, tape->name, vendor_id, product_id, fw_rev); 2061} 2062 2063/* 2064 * Ask the tape about its various parameters. In particular, we will adjust our 2065 * data transfer buffer size to the recommended value as returned by the tape. 2066 */ 2067static void idetape_get_mode_sense_results(ide_drive_t *drive) 2068{ 2069 idetape_tape_t *tape = drive->driver_data; 2070 struct ide_atapi_pc pc; 2071 u8 *caps; 2072 u8 speed, max_speed; 2073 2074 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2075 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2076 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2077 " some default values\n"); 2078 tape->blk_size = 512; 2079 put_unaligned(52, (u16 *)&tape->caps[12]); 2080 put_unaligned(540, (u16 *)&tape->caps[14]); 2081 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2082 return; 2083 } 2084 caps = pc.buf + 4 + pc.buf[3]; 2085 2086 /* convert to host order and save for later use */ 2087 speed = be16_to_cpup((__be16 *)&caps[14]); 2088 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2089 2090 *(u16 *)&caps[8] = max_speed; 2091 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2092 *(u16 *)&caps[14] = speed; 2093 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2094 2095 if (!speed) { 2096 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2097 "(assuming 650KB/sec)\n", drive->name); 2098 *(u16 *)&caps[14] = 650; 2099 } 2100 if (!max_speed) { 2101 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2102 "(assuming 650KB/sec)\n", drive->name); 2103 *(u16 *)&caps[8] = 650; 2104 } 2105 2106 memcpy(&tape->caps, caps, 20); 2107 2108 /* device lacks locking support according to capabilities page */ 2109 if ((caps[6] & 1) == 0) 2110 drive->atapi_flags |= IDE_AFLAG_NO_DOORLOCK; 2111 2112 if (caps[7] & 0x02) 2113 tape->blk_size = 512; 2114 else if (caps[7] & 0x04) 2115 tape->blk_size = 1024; 2116} 2117 2118#ifdef CONFIG_IDE_PROC_FS 2119#define ide_tape_devset_get(name, field) \ 2120static int get_##name(ide_drive_t *drive) \ 2121{ \ 2122 idetape_tape_t *tape = drive->driver_data; \ 2123 return tape->field; \ 2124} 2125 2126#define ide_tape_devset_set(name, field) \ 2127static int set_##name(ide_drive_t *drive, int arg) \ 2128{ \ 2129 idetape_tape_t *tape = drive->driver_data; \ 2130 tape->field = arg; \ 2131 return 0; \ 2132} 2133 2134#define ide_tape_devset_rw_field(_name, _field) \ 2135ide_tape_devset_get(_name, _field) \ 2136ide_tape_devset_set(_name, _field) \ 2137IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name) 2138 2139#define ide_tape_devset_r_field(_name, _field) \ 2140ide_tape_devset_get(_name, _field) \ 2141IDE_DEVSET(_name, 0, get_##_name, NULL) 2142 2143static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2144static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2145static int divf_buffer(ide_drive_t *drive) { return 2; } 2146static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2147 2148ide_devset_rw_field(dsc_overlap, dsc_overlap); 2149 2150ide_tape_devset_rw_field(debug_mask, debug_mask); 2151ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq); 2152 2153ide_tape_devset_r_field(avg_speed, avg_speed); 2154ide_tape_devset_r_field(speed, caps[14]); 2155ide_tape_devset_r_field(buffer, caps[16]); 2156ide_tape_devset_r_field(buffer_size, buffer_size); 2157 2158static const struct ide_proc_devset idetape_settings[] = { 2159 __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), 2160 __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), 2161 __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), 2162 __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), 2163 __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), 2164 __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), 2165 __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2166 mulf_tdsc, divf_tdsc), 2167 { 0 }, 2168}; 2169#endif 2170 2171/* 2172 * The function below is called to: 2173 * 2174 * 1. Initialize our various state variables. 2175 * 2. Ask the tape for its capabilities. 2176 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2177 * is chosen based on the recommendation which we received in step 2. 2178 * 2179 * Note that at this point ide.c already assigned us an irq, so that we can 2180 * queue requests here and wait for their completion. 2181 */ 2182static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2183{ 2184 unsigned long t; 2185 int speed; 2186 int buffer_size; 2187 u8 gcw[2]; 2188 u16 *ctl = (u16 *)&tape->caps[12]; 2189 2190 drive->pc_callback = ide_tape_callback; 2191 drive->pc_update_buffers = idetape_update_buffers; 2192 drive->pc_io_buffers = ide_tape_io_buffers; 2193 2194 spin_lock_init(&tape->lock); 2195 drive->dsc_overlap = 1; 2196 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2197 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2198 tape->name); 2199 drive->dsc_overlap = 0; 2200 } 2201 /* Seagate Travan drives do not support DSC overlap. */ 2202 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2203 drive->dsc_overlap = 0; 2204 tape->minor = minor; 2205 tape->name[0] = 'h'; 2206 tape->name[1] = 't'; 2207 tape->name[2] = '0' + minor; 2208 tape->chrdev_dir = IDETAPE_DIR_NONE; 2209 2210 *((u16 *)&gcw) = drive->id[ATA_ID_CONFIG]; 2211 2212 /* Command packet DRQ type */ 2213 if (((gcw[0] & 0x60) >> 5) == 1) 2214 set_bit(IDE_AFLAG_DRQ_INTERRUPT, &drive->atapi_flags); 2215 2216 idetape_get_inquiry_results(drive); 2217 idetape_get_mode_sense_results(drive); 2218 ide_tape_get_bsize_from_bdesc(drive); 2219 tape->user_bs_factor = 1; 2220 tape->buffer_size = *ctl * tape->blk_size; 2221 while (tape->buffer_size > 0xffff) { 2222 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2223 *ctl /= 2; 2224 tape->buffer_size = *ctl * tape->blk_size; 2225 } 2226 buffer_size = tape->buffer_size; 2227 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2228 if (buffer_size % PAGE_SIZE) { 2229 tape->pages_per_buffer++; 2230 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2231 } 2232 2233 /* select the "best" DSC read/write polling freq */ 2234 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2235 2236 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2237 2238 /* 2239 * Ensure that the number we got makes sense; limit it within 2240 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2241 */ 2242 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2243 IDETAPE_DSC_RW_MAX); 2244 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2245 "%lums tDSC%s\n", 2246 drive->name, tape->name, *(u16 *)&tape->caps[14], 2247 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2248 tape->buffer_size / 1024, 2249 tape->best_dsc_rw_freq * 1000 / HZ, 2250 drive->using_dma ? ", DMA":""); 2251 2252 ide_proc_register_driver(drive, tape->driver); 2253} 2254 2255static void ide_tape_remove(ide_drive_t *drive) 2256{ 2257 idetape_tape_t *tape = drive->driver_data; 2258 2259 ide_proc_unregister_driver(drive, tape->driver); 2260 2261 ide_unregister_region(tape->disk); 2262 2263 ide_tape_put(tape); 2264} 2265 2266static void ide_tape_release(struct kref *kref) 2267{ 2268 struct ide_tape_obj *tape = to_ide_drv(kref, ide_tape_obj); 2269 ide_drive_t *drive = tape->drive; 2270 struct gendisk *g = tape->disk; 2271 2272 BUG_ON(tape->merge_bh_size); 2273 2274 drive->dsc_overlap = 0; 2275 drive->driver_data = NULL; 2276 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2277 device_destroy(idetape_sysfs_class, 2278 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2279 idetape_devs[tape->minor] = NULL; 2280 g->private_data = NULL; 2281 put_disk(g); 2282 kfree(tape); 2283} 2284 2285#ifdef CONFIG_IDE_PROC_FS 2286static int proc_idetape_read_name 2287 (char *page, char **start, off_t off, int count, int *eof, void *data) 2288{ 2289 ide_drive_t *drive = (ide_drive_t *) data; 2290 idetape_tape_t *tape = drive->driver_data; 2291 char *out = page; 2292 int len; 2293 2294 len = sprintf(out, "%s\n", tape->name); 2295 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2296} 2297 2298static ide_proc_entry_t idetape_proc[] = { 2299 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2300 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2301 { NULL, 0, NULL, NULL } 2302}; 2303#endif 2304 2305static int ide_tape_probe(ide_drive_t *); 2306 2307static ide_driver_t idetape_driver = { 2308 .gen_driver = { 2309 .owner = THIS_MODULE, 2310 .name = "ide-tape", 2311 .bus = &ide_bus_type, 2312 }, 2313 .probe = ide_tape_probe, 2314 .remove = ide_tape_remove, 2315 .version = IDETAPE_VERSION, 2316 .media = ide_tape, 2317 .do_request = idetape_do_request, 2318 .end_request = idetape_end_request, 2319 .error = __ide_error, 2320#ifdef CONFIG_IDE_PROC_FS 2321 .proc = idetape_proc, 2322 .settings = idetape_settings, 2323#endif 2324}; 2325 2326/* Our character device supporting functions, passed to register_chrdev. */ 2327static const struct file_operations idetape_fops = { 2328 .owner = THIS_MODULE, 2329 .read = idetape_chrdev_read, 2330 .write = idetape_chrdev_write, 2331 .ioctl = idetape_chrdev_ioctl, 2332 .open = idetape_chrdev_open, 2333 .release = idetape_chrdev_release, 2334}; 2335 2336static int idetape_open(struct inode *inode, struct file *filp) 2337{ 2338 struct gendisk *disk = inode->i_bdev->bd_disk; 2339 struct ide_tape_obj *tape; 2340 2341 tape = ide_tape_get(disk); 2342 if (!tape) 2343 return -ENXIO; 2344 2345 return 0; 2346} 2347 2348static int idetape_release(struct inode *inode, struct file *filp) 2349{ 2350 struct gendisk *disk = inode->i_bdev->bd_disk; 2351 struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj); 2352 2353 ide_tape_put(tape); 2354 2355 return 0; 2356} 2357 2358static int idetape_ioctl(struct inode *inode, struct file *file, 2359 unsigned int cmd, unsigned long arg) 2360{ 2361 struct block_device *bdev = inode->i_bdev; 2362 struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj); 2363 ide_drive_t *drive = tape->drive; 2364 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 2365 if (err == -EINVAL) 2366 err = idetape_blkdev_ioctl(drive, cmd, arg); 2367 return err; 2368} 2369 2370static struct block_device_operations idetape_block_ops = { 2371 .owner = THIS_MODULE, 2372 .open = idetape_open, 2373 .release = idetape_release, 2374 .ioctl = idetape_ioctl, 2375}; 2376 2377static int ide_tape_probe(ide_drive_t *drive) 2378{ 2379 idetape_tape_t *tape; 2380 struct gendisk *g; 2381 int minor; 2382 2383 if (!strstr("ide-tape", drive->driver_req)) 2384 goto failed; 2385 2386 if (drive->media != ide_tape) 2387 goto failed; 2388 2389 if (drive->id_read == 1 && !ide_check_atapi_device(drive, DRV_NAME)) { 2390 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2391 " the driver\n", drive->name); 2392 goto failed; 2393 } 2394 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2395 if (tape == NULL) { 2396 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2397 drive->name); 2398 goto failed; 2399 } 2400 2401 g = alloc_disk(1 << PARTN_BITS); 2402 if (!g) 2403 goto out_free_tape; 2404 2405 ide_init_disk(g, drive); 2406 2407 kref_init(&tape->kref); 2408 2409 tape->drive = drive; 2410 tape->driver = &idetape_driver; 2411 tape->disk = g; 2412 2413 g->private_data = &tape->driver; 2414 2415 drive->driver_data = tape; 2416 2417 mutex_lock(&idetape_ref_mutex); 2418 for (minor = 0; idetape_devs[minor]; minor++) 2419 ; 2420 idetape_devs[minor] = tape; 2421 mutex_unlock(&idetape_ref_mutex); 2422 2423 idetape_setup(drive, tape, minor); 2424 2425 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2426 MKDEV(IDETAPE_MAJOR, minor), NULL, 2427 "%s", tape->name); 2428 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2429 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2430 "n%s", tape->name); 2431 2432 g->fops = &idetape_block_ops; 2433 ide_register_region(g); 2434 2435 return 0; 2436 2437out_free_tape: 2438 kfree(tape); 2439failed: 2440 return -ENODEV; 2441} 2442 2443static void __exit idetape_exit(void) 2444{ 2445 driver_unregister(&idetape_driver.gen_driver); 2446 class_destroy(idetape_sysfs_class); 2447 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2448} 2449 2450static int __init idetape_init(void) 2451{ 2452 int error = 1; 2453 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2454 if (IS_ERR(idetape_sysfs_class)) { 2455 idetape_sysfs_class = NULL; 2456 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2457 error = -EBUSY; 2458 goto out; 2459 } 2460 2461 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2462 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2463 " interface\n"); 2464 error = -EBUSY; 2465 goto out_free_class; 2466 } 2467 2468 error = driver_register(&idetape_driver.gen_driver); 2469 if (error) 2470 goto out_free_driver; 2471 2472 return 0; 2473 2474out_free_driver: 2475 driver_unregister(&idetape_driver.gen_driver); 2476out_free_class: 2477 class_destroy(idetape_sysfs_class); 2478out: 2479 return error; 2480} 2481 2482MODULE_ALIAS("ide:*m-tape*"); 2483module_init(idetape_init); 2484module_exit(idetape_exit); 2485MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2486MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2487MODULE_LICENSE("GPL"); 2488