ide-tape.c revision 5e2040fd0a97888952b37243b5868872bbe0f6ac
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 struct ide_driver *driver; 171 struct gendisk *disk; 172 struct device dev; 173 174 /* used by REQ_IDETAPE_{READ,WRITE} requests */ 175 struct ide_atapi_pc queued_pc; 176 177 /* 178 * DSC polling variables. 179 * 180 * While polling for DSC we use postponed_rq to postpone the current 181 * request so that ide.c will be able to service pending requests on the 182 * other device. Note that at most we will have only one DSC (usually 183 * data transfer) request in the device request queue. 184 */ 185 struct request *postponed_rq; 186 /* The time in which we started polling for DSC */ 187 unsigned long dsc_polling_start; 188 /* Timer used to poll for dsc */ 189 struct timer_list dsc_timer; 190 /* Read/Write dsc polling frequency */ 191 unsigned long best_dsc_rw_freq; 192 unsigned long dsc_poll_freq; 193 unsigned long dsc_timeout; 194 195 /* Read position information */ 196 u8 partition; 197 /* Current block */ 198 unsigned int first_frame; 199 200 /* Last error information */ 201 u8 sense_key, asc, ascq; 202 203 /* Character device operation */ 204 unsigned int minor; 205 /* device name */ 206 char name[4]; 207 /* Current character device data transfer direction */ 208 u8 chrdev_dir; 209 210 /* tape block size, usually 512 or 1024 bytes */ 211 unsigned short blk_size; 212 int user_bs_factor; 213 214 /* Copy of the tape's Capabilities and Mechanical Page */ 215 u8 caps[20]; 216 217 /* 218 * Active data transfer request parameters. 219 * 220 * At most, there is only one ide-tape originated data transfer request 221 * in the device request queue. This allows ide.c to easily service 222 * requests from the other device when we postpone our active request. 223 */ 224 225 /* Data buffer size chosen based on the tape's recommendation */ 226 int buffer_size; 227 /* merge buffer */ 228 struct idetape_bh *merge_bh; 229 /* size of the merge buffer */ 230 int merge_bh_size; 231 /* pointer to current buffer head within the merge buffer */ 232 struct idetape_bh *bh; 233 char *b_data; 234 int b_count; 235 236 int pages_per_buffer; 237 /* Wasted space in each stage */ 238 int excess_bh_size; 239 240 /* Measures average tape speed */ 241 unsigned long avg_time; 242 int avg_size; 243 int avg_speed; 244 245 /* the door is currently locked */ 246 int door_locked; 247 /* the tape hardware is write protected */ 248 char drv_write_prot; 249 /* the tape is write protected (hardware or opened as read-only) */ 250 char write_prot; 251 252 u32 debug_mask; 253} idetape_tape_t; 254 255static DEFINE_MUTEX(idetape_ref_mutex); 256 257static struct class *idetape_sysfs_class; 258 259static void ide_tape_release(struct device *); 260 261static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 262{ 263 struct ide_tape_obj *tape = NULL; 264 265 mutex_lock(&idetape_ref_mutex); 266 tape = ide_drv_g(disk, ide_tape_obj); 267 if (tape) { 268 if (ide_device_get(tape->drive)) 269 tape = NULL; 270 else 271 get_device(&tape->dev); 272 } 273 mutex_unlock(&idetape_ref_mutex); 274 return tape; 275} 276 277static void ide_tape_put(struct ide_tape_obj *tape) 278{ 279 ide_drive_t *drive = tape->drive; 280 281 mutex_lock(&idetape_ref_mutex); 282 put_device(&tape->dev); 283 ide_device_put(drive); 284 mutex_unlock(&idetape_ref_mutex); 285} 286 287/* 288 * The variables below are used for the character device interface. Additional 289 * state variables are defined in our ide_drive_t structure. 290 */ 291static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES]; 292 293static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 294{ 295 struct ide_tape_obj *tape = NULL; 296 297 mutex_lock(&idetape_ref_mutex); 298 tape = idetape_devs[i]; 299 if (tape) 300 get_device(&tape->dev); 301 mutex_unlock(&idetape_ref_mutex); 302 return tape; 303} 304 305static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 306 unsigned int bcount) 307{ 308 struct idetape_bh *bh = pc->bh; 309 int count; 310 311 while (bcount) { 312 if (bh == NULL) { 313 printk(KERN_ERR "ide-tape: bh == NULL in " 314 "idetape_input_buffers\n"); 315 ide_pad_transfer(drive, 0, bcount); 316 return; 317 } 318 count = min( 319 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 320 bcount); 321 drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data + 322 atomic_read(&bh->b_count), count); 323 bcount -= count; 324 atomic_add(count, &bh->b_count); 325 if (atomic_read(&bh->b_count) == bh->b_size) { 326 bh = bh->b_reqnext; 327 if (bh) 328 atomic_set(&bh->b_count, 0); 329 } 330 } 331 pc->bh = bh; 332} 333 334static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 335 unsigned int bcount) 336{ 337 struct idetape_bh *bh = pc->bh; 338 int count; 339 340 while (bcount) { 341 if (bh == NULL) { 342 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 343 __func__); 344 return; 345 } 346 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 347 drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); 348 bcount -= count; 349 pc->b_data += count; 350 pc->b_count -= count; 351 if (!pc->b_count) { 352 bh = bh->b_reqnext; 353 pc->bh = bh; 354 if (bh) { 355 pc->b_data = bh->b_data; 356 pc->b_count = atomic_read(&bh->b_count); 357 } 358 } 359 } 360} 361 362static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) 363{ 364 struct idetape_bh *bh = pc->bh; 365 int count; 366 unsigned int bcount = pc->xferred; 367 368 if (pc->flags & PC_FLAG_WRITING) 369 return; 370 while (bcount) { 371 if (bh == NULL) { 372 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 373 __func__); 374 return; 375 } 376 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 377 atomic_set(&bh->b_count, count); 378 if (atomic_read(&bh->b_count) == bh->b_size) 379 bh = bh->b_reqnext; 380 bcount -= count; 381 } 382 pc->bh = bh; 383} 384 385/* 386 * called on each failed packet command retry to analyze the request sense. We 387 * currently do not utilize this information. 388 */ 389static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 390{ 391 idetape_tape_t *tape = drive->driver_data; 392 struct ide_atapi_pc *pc = drive->failed_pc; 393 394 tape->sense_key = sense[2] & 0xF; 395 tape->asc = sense[12]; 396 tape->ascq = sense[13]; 397 398 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 399 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 400 401 /* Correct pc->xferred by asking the tape. */ 402 if (pc->flags & PC_FLAG_DMA_ERROR) { 403 pc->xferred = pc->req_xfer - 404 tape->blk_size * 405 get_unaligned_be32(&sense[3]); 406 idetape_update_buffers(drive, pc); 407 } 408 409 /* 410 * If error was the result of a zero-length read or write command, 411 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 412 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 413 */ 414 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 415 /* length == 0 */ 416 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 417 if (tape->sense_key == 5) { 418 /* don't report an error, everything's ok */ 419 pc->error = 0; 420 /* don't retry read/write */ 421 pc->flags |= PC_FLAG_ABORT; 422 } 423 } 424 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 425 pc->error = IDETAPE_ERROR_FILEMARK; 426 pc->flags |= PC_FLAG_ABORT; 427 } 428 if (pc->c[0] == WRITE_6) { 429 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 430 && tape->asc == 0x0 && tape->ascq == 0x2)) { 431 pc->error = IDETAPE_ERROR_EOD; 432 pc->flags |= PC_FLAG_ABORT; 433 } 434 } 435 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 436 if (tape->sense_key == 8) { 437 pc->error = IDETAPE_ERROR_EOD; 438 pc->flags |= PC_FLAG_ABORT; 439 } 440 if (!(pc->flags & PC_FLAG_ABORT) && 441 pc->xferred) 442 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 443 } 444} 445 446/* Free data buffers completely. */ 447static void ide_tape_kfree_buffer(idetape_tape_t *tape) 448{ 449 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 450 451 while (bh) { 452 u32 size = bh->b_size; 453 454 while (size) { 455 unsigned int order = fls(size >> PAGE_SHIFT)-1; 456 457 if (bh->b_data) 458 free_pages((unsigned long)bh->b_data, order); 459 460 size &= (order-1); 461 bh->b_data += (1 << order) * PAGE_SIZE; 462 } 463 prev_bh = bh; 464 bh = bh->b_reqnext; 465 kfree(prev_bh); 466 } 467} 468 469static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 470{ 471 struct request *rq = drive->hwif->rq; 472 int error; 473 474 debug_log(DBG_PROCS, "Enter %s\n", __func__); 475 476 switch (uptodate) { 477 case 0: error = IDETAPE_ERROR_GENERAL; break; 478 case 1: error = 0; break; 479 default: error = uptodate; 480 } 481 rq->errors = error; 482 if (error) 483 drive->failed_pc = NULL; 484 485 if (!blk_special_request(rq)) { 486 ide_end_request(drive, uptodate, nr_sects); 487 return 0; 488 } 489 490 ide_complete_rq(drive, 0); 491 492 return 0; 493} 494 495static void ide_tape_handle_dsc(ide_drive_t *); 496 497static void ide_tape_callback(ide_drive_t *drive, int dsc) 498{ 499 idetape_tape_t *tape = drive->driver_data; 500 struct ide_atapi_pc *pc = drive->pc; 501 int uptodate = pc->error ? 0 : 1; 502 503 debug_log(DBG_PROCS, "Enter %s\n", __func__); 504 505 if (dsc) 506 ide_tape_handle_dsc(drive); 507 508 if (drive->failed_pc == pc) 509 drive->failed_pc = NULL; 510 511 if (pc->c[0] == REQUEST_SENSE) { 512 if (uptodate) 513 idetape_analyze_error(drive, pc->buf); 514 else 515 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 516 "itself - Aborting request!\n"); 517 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 518 struct request *rq = drive->hwif->rq; 519 int blocks = pc->xferred / tape->blk_size; 520 521 tape->avg_size += blocks * tape->blk_size; 522 523 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 524 tape->avg_speed = tape->avg_size * HZ / 525 (jiffies - tape->avg_time) / 1024; 526 tape->avg_size = 0; 527 tape->avg_time = jiffies; 528 } 529 530 tape->first_frame += blocks; 531 rq->current_nr_sectors -= blocks; 532 533 if (pc->error) 534 uptodate = pc->error; 535 } else if (pc->c[0] == READ_POSITION && uptodate) { 536 u8 *readpos = pc->buf; 537 538 debug_log(DBG_SENSE, "BOP - %s\n", 539 (readpos[0] & 0x80) ? "Yes" : "No"); 540 debug_log(DBG_SENSE, "EOP - %s\n", 541 (readpos[0] & 0x40) ? "Yes" : "No"); 542 543 if (readpos[0] & 0x4) { 544 printk(KERN_INFO "ide-tape: Block location is unknown" 545 "to the tape\n"); 546 clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 547 uptodate = 0; 548 } else { 549 debug_log(DBG_SENSE, "Block Location - %u\n", 550 be32_to_cpup((__be32 *)&readpos[4])); 551 552 tape->partition = readpos[1]; 553 tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]); 554 set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 555 } 556 } 557 558 idetape_end_request(drive, uptodate, 0); 559} 560 561/* 562 * Postpone the current request so that ide.c will be able to service requests 563 * from another device on the same port while we are polling for DSC. 564 */ 565static void idetape_postpone_request(ide_drive_t *drive) 566{ 567 idetape_tape_t *tape = drive->driver_data; 568 569 debug_log(DBG_PROCS, "Enter %s\n", __func__); 570 571 tape->postponed_rq = drive->hwif->rq; 572 573 ide_stall_queue(drive, tape->dsc_poll_freq); 574} 575 576static void ide_tape_handle_dsc(ide_drive_t *drive) 577{ 578 idetape_tape_t *tape = drive->driver_data; 579 580 /* Media access command */ 581 tape->dsc_polling_start = jiffies; 582 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 583 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 584 /* Allow ide.c to handle other requests */ 585 idetape_postpone_request(drive); 586} 587 588static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 589 unsigned int bcount, int write) 590{ 591 if (write) 592 idetape_output_buffers(drive, pc, bcount); 593 else 594 idetape_input_buffers(drive, pc, bcount); 595 596 return bcount; 597} 598 599/* 600 * Packet Command Interface 601 * 602 * The current Packet Command is available in drive->pc, and will not change 603 * until we finish handling it. Each packet command is associated with a 604 * callback function that will be called when the command is finished. 605 * 606 * The handling will be done in three stages: 607 * 608 * 1. idetape_issue_pc will send the packet command to the drive, and will set 609 * the interrupt handler to ide_pc_intr. 610 * 611 * 2. On each interrupt, ide_pc_intr will be called. This step will be 612 * repeated until the device signals us that no more interrupts will be issued. 613 * 614 * 3. ATAPI Tape media access commands have immediate status with a delayed 615 * process. In case of a successful initiation of a media access packet command, 616 * the DSC bit will be set when the actual execution of the command is finished. 617 * Since the tape drive will not issue an interrupt, we have to poll for this 618 * event. In this case, we define the request as "low priority request" by 619 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 620 * exit the driver. 621 * 622 * ide.c will then give higher priority to requests which originate from the 623 * other device, until will change rq_status to RQ_ACTIVE. 624 * 625 * 4. When the packet command is finished, it will be checked for errors. 626 * 627 * 5. In case an error was found, we queue a request sense packet command in 628 * front of the request queue and retry the operation up to 629 * IDETAPE_MAX_PC_RETRIES times. 630 * 631 * 6. In case no error was found, or we decided to give up and not to retry 632 * again, the callback function will be called and then we will handle the next 633 * request. 634 */ 635 636static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 637 struct ide_atapi_pc *pc) 638{ 639 idetape_tape_t *tape = drive->driver_data; 640 641 if (drive->pc->c[0] == REQUEST_SENSE && 642 pc->c[0] == REQUEST_SENSE) { 643 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 644 "Two request sense in serial were issued\n"); 645 } 646 647 if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 648 drive->failed_pc = pc; 649 650 /* Set the current packet command */ 651 drive->pc = pc; 652 653 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 654 (pc->flags & PC_FLAG_ABORT)) { 655 /* 656 * We will "abort" retrying a packet command in case legitimate 657 * error code was received (crossing a filemark, or end of the 658 * media, for example). 659 */ 660 if (!(pc->flags & PC_FLAG_ABORT)) { 661 if (!(pc->c[0] == TEST_UNIT_READY && 662 tape->sense_key == 2 && tape->asc == 4 && 663 (tape->ascq == 1 || tape->ascq == 8))) { 664 printk(KERN_ERR "ide-tape: %s: I/O error, " 665 "pc = %2x, key = %2x, " 666 "asc = %2x, ascq = %2x\n", 667 tape->name, pc->c[0], 668 tape->sense_key, tape->asc, 669 tape->ascq); 670 } 671 /* Giving up */ 672 pc->error = IDETAPE_ERROR_GENERAL; 673 } 674 drive->failed_pc = NULL; 675 drive->pc_callback(drive, 0); 676 return ide_stopped; 677 } 678 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 679 680 pc->retries++; 681 682 return ide_issue_pc(drive); 683} 684 685/* A mode sense command is used to "sense" tape parameters. */ 686static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 687{ 688 ide_init_pc(pc); 689 pc->c[0] = MODE_SENSE; 690 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 691 /* DBD = 1 - Don't return block descriptors */ 692 pc->c[1] = 8; 693 pc->c[2] = page_code; 694 /* 695 * Changed pc->c[3] to 0 (255 will at best return unused info). 696 * 697 * For SCSI this byte is defined as subpage instead of high byte 698 * of length and some IDE drives seem to interpret it this way 699 * and return an error when 255 is used. 700 */ 701 pc->c[3] = 0; 702 /* We will just discard data in that case */ 703 pc->c[4] = 255; 704 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 705 pc->req_xfer = 12; 706 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 707 pc->req_xfer = 24; 708 else 709 pc->req_xfer = 50; 710} 711 712static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 713{ 714 ide_hwif_t *hwif = drive->hwif; 715 idetape_tape_t *tape = drive->driver_data; 716 struct ide_atapi_pc *pc = drive->pc; 717 u8 stat; 718 719 stat = hwif->tp_ops->read_status(hwif); 720 721 if (stat & ATA_DSC) { 722 if (stat & ATA_ERR) { 723 /* Error detected */ 724 if (pc->c[0] != TEST_UNIT_READY) 725 printk(KERN_ERR "ide-tape: %s: I/O error, ", 726 tape->name); 727 /* Retry operation */ 728 ide_retry_pc(drive, tape->disk); 729 return ide_stopped; 730 } 731 pc->error = 0; 732 } else { 733 pc->error = IDETAPE_ERROR_GENERAL; 734 drive->failed_pc = NULL; 735 } 736 drive->pc_callback(drive, 0); 737 return ide_stopped; 738} 739 740static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 741 struct ide_atapi_pc *pc, struct request *rq, 742 u8 opcode) 743{ 744 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 745 unsigned int length = rq->current_nr_sectors; 746 747 ide_init_pc(pc); 748 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 749 pc->c[1] = 1; 750 pc->bh = bh; 751 pc->buf = NULL; 752 pc->buf_size = length * tape->blk_size; 753 pc->req_xfer = pc->buf_size; 754 if (pc->req_xfer == tape->buffer_size) 755 pc->flags |= PC_FLAG_DMA_OK; 756 757 if (opcode == READ_6) { 758 pc->c[0] = READ_6; 759 atomic_set(&bh->b_count, 0); 760 } else if (opcode == WRITE_6) { 761 pc->c[0] = WRITE_6; 762 pc->flags |= PC_FLAG_WRITING; 763 pc->b_data = bh->b_data; 764 pc->b_count = atomic_read(&bh->b_count); 765 } 766 767 memcpy(rq->cmd, pc->c, 12); 768} 769 770static ide_startstop_t idetape_do_request(ide_drive_t *drive, 771 struct request *rq, sector_t block) 772{ 773 ide_hwif_t *hwif = drive->hwif; 774 idetape_tape_t *tape = drive->driver_data; 775 struct ide_atapi_pc *pc = NULL; 776 struct request *postponed_rq = tape->postponed_rq; 777 u8 stat; 778 779 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 780 " current_nr_sectors: %u\n", 781 (unsigned long long)rq->sector, rq->nr_sectors, 782 rq->current_nr_sectors); 783 784 if (!blk_special_request(rq)) { 785 /* We do not support buffer cache originated requests. */ 786 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 787 "request queue (%d)\n", drive->name, rq->cmd_type); 788 ide_end_request(drive, 0, 0); 789 return ide_stopped; 790 } 791 792 /* Retry a failed packet command */ 793 if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { 794 pc = drive->failed_pc; 795 goto out; 796 } 797 798 if (postponed_rq != NULL) 799 if (rq != postponed_rq) { 800 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 801 "Two DSC requests were queued\n"); 802 idetape_end_request(drive, 0, 0); 803 return ide_stopped; 804 } 805 806 tape->postponed_rq = NULL; 807 808 /* 809 * If the tape is still busy, postpone our request and service 810 * the other device meanwhile. 811 */ 812 stat = hwif->tp_ops->read_status(hwif); 813 814 if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 && 815 (rq->cmd[13] & REQ_IDETAPE_PC2) == 0) 816 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 817 818 if (drive->dev_flags & IDE_DFLAG_POST_RESET) { 819 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 820 drive->dev_flags &= ~IDE_DFLAG_POST_RESET; 821 } 822 823 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 824 (stat & ATA_DSC) == 0) { 825 if (postponed_rq == NULL) { 826 tape->dsc_polling_start = jiffies; 827 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 828 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 829 } else if (time_after(jiffies, tape->dsc_timeout)) { 830 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 831 tape->name); 832 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 833 idetape_media_access_finished(drive); 834 return ide_stopped; 835 } else { 836 return ide_do_reset(drive); 837 } 838 } else if (time_after(jiffies, 839 tape->dsc_polling_start + 840 IDETAPE_DSC_MA_THRESHOLD)) 841 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 842 idetape_postpone_request(drive); 843 return ide_stopped; 844 } 845 if (rq->cmd[13] & REQ_IDETAPE_READ) { 846 pc = &tape->queued_pc; 847 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 848 goto out; 849 } 850 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 851 pc = &tape->queued_pc; 852 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 853 goto out; 854 } 855 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 856 pc = (struct ide_atapi_pc *) rq->buffer; 857 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 858 rq->cmd[13] |= REQ_IDETAPE_PC2; 859 goto out; 860 } 861 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 862 idetape_media_access_finished(drive); 863 return ide_stopped; 864 } 865 BUG(); 866 867out: 868 return idetape_issue_pc(drive, pc); 869} 870 871/* 872 * The function below uses __get_free_pages to allocate a data buffer of size 873 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 874 * much as possible. 875 * 876 * It returns a pointer to the newly allocated buffer, or NULL in case of 877 * failure. 878 */ 879static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 880 int full, int clear) 881{ 882 struct idetape_bh *prev_bh, *bh, *merge_bh; 883 int pages = tape->pages_per_buffer; 884 unsigned int order, b_allocd; 885 char *b_data = NULL; 886 887 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 888 bh = merge_bh; 889 if (bh == NULL) 890 goto abort; 891 892 order = fls(pages) - 1; 893 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 894 if (!bh->b_data) 895 goto abort; 896 b_allocd = (1 << order) * PAGE_SIZE; 897 pages &= (order-1); 898 899 if (clear) 900 memset(bh->b_data, 0, b_allocd); 901 bh->b_reqnext = NULL; 902 bh->b_size = b_allocd; 903 atomic_set(&bh->b_count, full ? bh->b_size : 0); 904 905 while (pages) { 906 order = fls(pages) - 1; 907 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 908 if (!b_data) 909 goto abort; 910 b_allocd = (1 << order) * PAGE_SIZE; 911 912 if (clear) 913 memset(b_data, 0, b_allocd); 914 915 /* newly allocated page frames below buffer header or ...*/ 916 if (bh->b_data == b_data + b_allocd) { 917 bh->b_size += b_allocd; 918 bh->b_data -= b_allocd; 919 if (full) 920 atomic_add(b_allocd, &bh->b_count); 921 continue; 922 } 923 /* they are above the header */ 924 if (b_data == bh->b_data + bh->b_size) { 925 bh->b_size += b_allocd; 926 if (full) 927 atomic_add(b_allocd, &bh->b_count); 928 continue; 929 } 930 prev_bh = bh; 931 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 932 if (!bh) { 933 free_pages((unsigned long) b_data, order); 934 goto abort; 935 } 936 bh->b_reqnext = NULL; 937 bh->b_data = b_data; 938 bh->b_size = b_allocd; 939 atomic_set(&bh->b_count, full ? bh->b_size : 0); 940 prev_bh->b_reqnext = bh; 941 942 pages &= (order-1); 943 } 944 945 bh->b_size -= tape->excess_bh_size; 946 if (full) 947 atomic_sub(tape->excess_bh_size, &bh->b_count); 948 return merge_bh; 949abort: 950 ide_tape_kfree_buffer(tape); 951 return NULL; 952} 953 954static int idetape_copy_stage_from_user(idetape_tape_t *tape, 955 const char __user *buf, int n) 956{ 957 struct idetape_bh *bh = tape->bh; 958 int count; 959 int ret = 0; 960 961 while (n) { 962 if (bh == NULL) { 963 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 964 __func__); 965 return 1; 966 } 967 count = min((unsigned int) 968 (bh->b_size - atomic_read(&bh->b_count)), 969 (unsigned int)n); 970 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 971 count)) 972 ret = 1; 973 n -= count; 974 atomic_add(count, &bh->b_count); 975 buf += count; 976 if (atomic_read(&bh->b_count) == bh->b_size) { 977 bh = bh->b_reqnext; 978 if (bh) 979 atomic_set(&bh->b_count, 0); 980 } 981 } 982 tape->bh = bh; 983 return ret; 984} 985 986static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 987 int n) 988{ 989 struct idetape_bh *bh = tape->bh; 990 int count; 991 int ret = 0; 992 993 while (n) { 994 if (bh == NULL) { 995 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 996 __func__); 997 return 1; 998 } 999 count = min(tape->b_count, n); 1000 if (copy_to_user(buf, tape->b_data, count)) 1001 ret = 1; 1002 n -= count; 1003 tape->b_data += count; 1004 tape->b_count -= count; 1005 buf += count; 1006 if (!tape->b_count) { 1007 bh = bh->b_reqnext; 1008 tape->bh = bh; 1009 if (bh) { 1010 tape->b_data = bh->b_data; 1011 tape->b_count = atomic_read(&bh->b_count); 1012 } 1013 } 1014 } 1015 return ret; 1016} 1017 1018static void idetape_init_merge_buffer(idetape_tape_t *tape) 1019{ 1020 struct idetape_bh *bh = tape->merge_bh; 1021 tape->bh = tape->merge_bh; 1022 1023 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1024 atomic_set(&bh->b_count, 0); 1025 else { 1026 tape->b_data = bh->b_data; 1027 tape->b_count = atomic_read(&bh->b_count); 1028 } 1029} 1030 1031/* 1032 * Write a filemark if write_filemark=1. Flush the device buffers without 1033 * writing a filemark otherwise. 1034 */ 1035static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1036 struct ide_atapi_pc *pc, int write_filemark) 1037{ 1038 ide_init_pc(pc); 1039 pc->c[0] = WRITE_FILEMARKS; 1040 pc->c[4] = write_filemark; 1041 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1042} 1043 1044static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1045{ 1046 idetape_tape_t *tape = drive->driver_data; 1047 struct gendisk *disk = tape->disk; 1048 int load_attempted = 0; 1049 1050 /* Wait for the tape to become ready */ 1051 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1052 timeout += jiffies; 1053 while (time_before(jiffies, timeout)) { 1054 if (ide_do_test_unit_ready(drive, disk) == 0) 1055 return 0; 1056 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1057 || (tape->asc == 0x3A)) { 1058 /* no media */ 1059 if (load_attempted) 1060 return -ENOMEDIUM; 1061 ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1062 load_attempted = 1; 1063 /* not about to be ready */ 1064 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1065 (tape->ascq == 1 || tape->ascq == 8))) 1066 return -EIO; 1067 msleep(100); 1068 } 1069 return -EIO; 1070} 1071 1072static int idetape_flush_tape_buffers(ide_drive_t *drive) 1073{ 1074 struct ide_tape_obj *tape = drive->driver_data; 1075 struct ide_atapi_pc pc; 1076 int rc; 1077 1078 idetape_create_write_filemark_cmd(drive, &pc, 0); 1079 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1080 if (rc) 1081 return rc; 1082 idetape_wait_ready(drive, 60 * 5 * HZ); 1083 return 0; 1084} 1085 1086static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1087{ 1088 ide_init_pc(pc); 1089 pc->c[0] = READ_POSITION; 1090 pc->req_xfer = 20; 1091} 1092 1093static int idetape_read_position(ide_drive_t *drive) 1094{ 1095 idetape_tape_t *tape = drive->driver_data; 1096 struct ide_atapi_pc pc; 1097 int position; 1098 1099 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1100 1101 idetape_create_read_position_cmd(&pc); 1102 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1103 return -1; 1104 position = tape->first_frame; 1105 return position; 1106} 1107 1108static void idetape_create_locate_cmd(ide_drive_t *drive, 1109 struct ide_atapi_pc *pc, 1110 unsigned int block, u8 partition, int skip) 1111{ 1112 ide_init_pc(pc); 1113 pc->c[0] = POSITION_TO_ELEMENT; 1114 pc->c[1] = 2; 1115 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1116 pc->c[8] = partition; 1117 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1118} 1119 1120static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1121{ 1122 idetape_tape_t *tape = drive->driver_data; 1123 1124 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1125 return; 1126 1127 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1128 tape->merge_bh_size = 0; 1129 if (tape->merge_bh != NULL) { 1130 ide_tape_kfree_buffer(tape); 1131 tape->merge_bh = NULL; 1132 } 1133 1134 tape->chrdev_dir = IDETAPE_DIR_NONE; 1135} 1136 1137/* 1138 * Position the tape to the requested block using the LOCATE packet command. 1139 * A READ POSITION command is then issued to check where we are positioned. Like 1140 * all higher level operations, we queue the commands at the tail of the request 1141 * queue and wait for their completion. 1142 */ 1143static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1144 u8 partition, int skip) 1145{ 1146 idetape_tape_t *tape = drive->driver_data; 1147 struct gendisk *disk = tape->disk; 1148 int retval; 1149 struct ide_atapi_pc pc; 1150 1151 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1152 __ide_tape_discard_merge_buffer(drive); 1153 idetape_wait_ready(drive, 60 * 5 * HZ); 1154 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1155 retval = ide_queue_pc_tail(drive, disk, &pc); 1156 if (retval) 1157 return (retval); 1158 1159 idetape_create_read_position_cmd(&pc); 1160 return ide_queue_pc_tail(drive, disk, &pc); 1161} 1162 1163static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1164 int restore_position) 1165{ 1166 idetape_tape_t *tape = drive->driver_data; 1167 int seek, position; 1168 1169 __ide_tape_discard_merge_buffer(drive); 1170 if (restore_position) { 1171 position = idetape_read_position(drive); 1172 seek = position > 0 ? position : 0; 1173 if (idetape_position_tape(drive, seek, 0, 0)) { 1174 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1175 " %s\n", tape->name, __func__); 1176 return; 1177 } 1178 } 1179} 1180 1181/* 1182 * Generate a read/write request for the block device interface and wait for it 1183 * to be serviced. 1184 */ 1185static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1186 struct idetape_bh *bh) 1187{ 1188 idetape_tape_t *tape = drive->driver_data; 1189 struct request *rq; 1190 int ret, errors; 1191 1192 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1193 1194 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1195 rq->cmd_type = REQ_TYPE_SPECIAL; 1196 rq->cmd[13] = cmd; 1197 rq->rq_disk = tape->disk; 1198 rq->special = (void *)bh; 1199 rq->sector = tape->first_frame; 1200 rq->nr_sectors = blocks; 1201 rq->current_nr_sectors = blocks; 1202 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1203 1204 errors = rq->errors; 1205 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1206 blk_put_request(rq); 1207 1208 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1209 return 0; 1210 1211 if (tape->merge_bh) 1212 idetape_init_merge_buffer(tape); 1213 if (errors == IDETAPE_ERROR_GENERAL) 1214 return -EIO; 1215 return ret; 1216} 1217 1218static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1219{ 1220 ide_init_pc(pc); 1221 pc->c[0] = INQUIRY; 1222 pc->c[4] = 254; 1223 pc->req_xfer = 254; 1224} 1225 1226static void idetape_create_rewind_cmd(ide_drive_t *drive, 1227 struct ide_atapi_pc *pc) 1228{ 1229 ide_init_pc(pc); 1230 pc->c[0] = REZERO_UNIT; 1231 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1232} 1233 1234static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1235{ 1236 ide_init_pc(pc); 1237 pc->c[0] = ERASE; 1238 pc->c[1] = 1; 1239 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1240} 1241 1242static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1243{ 1244 ide_init_pc(pc); 1245 pc->c[0] = SPACE; 1246 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1247 pc->c[1] = cmd; 1248 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1249} 1250 1251/* Queue up a character device originated write request. */ 1252static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1253{ 1254 idetape_tape_t *tape = drive->driver_data; 1255 1256 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1257 1258 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1259 blocks, tape->merge_bh); 1260} 1261 1262static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1263{ 1264 idetape_tape_t *tape = drive->driver_data; 1265 int blocks, min; 1266 struct idetape_bh *bh; 1267 1268 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1269 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1270 " but we are not writing.\n"); 1271 return; 1272 } 1273 if (tape->merge_bh_size > tape->buffer_size) { 1274 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1275 tape->merge_bh_size = tape->buffer_size; 1276 } 1277 if (tape->merge_bh_size) { 1278 blocks = tape->merge_bh_size / tape->blk_size; 1279 if (tape->merge_bh_size % tape->blk_size) { 1280 unsigned int i; 1281 1282 blocks++; 1283 i = tape->blk_size - tape->merge_bh_size % 1284 tape->blk_size; 1285 bh = tape->bh->b_reqnext; 1286 while (bh) { 1287 atomic_set(&bh->b_count, 0); 1288 bh = bh->b_reqnext; 1289 } 1290 bh = tape->bh; 1291 while (i) { 1292 if (bh == NULL) { 1293 printk(KERN_INFO "ide-tape: bug," 1294 " bh NULL\n"); 1295 break; 1296 } 1297 min = min(i, (unsigned int)(bh->b_size - 1298 atomic_read(&bh->b_count))); 1299 memset(bh->b_data + atomic_read(&bh->b_count), 1300 0, min); 1301 atomic_add(min, &bh->b_count); 1302 i -= min; 1303 bh = bh->b_reqnext; 1304 } 1305 } 1306 (void) idetape_add_chrdev_write_request(drive, blocks); 1307 tape->merge_bh_size = 0; 1308 } 1309 if (tape->merge_bh != NULL) { 1310 ide_tape_kfree_buffer(tape); 1311 tape->merge_bh = NULL; 1312 } 1313 tape->chrdev_dir = IDETAPE_DIR_NONE; 1314} 1315 1316static int idetape_init_read(ide_drive_t *drive) 1317{ 1318 idetape_tape_t *tape = drive->driver_data; 1319 int bytes_read; 1320 1321 /* Initialize read operation */ 1322 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1323 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1324 ide_tape_flush_merge_buffer(drive); 1325 idetape_flush_tape_buffers(drive); 1326 } 1327 if (tape->merge_bh || tape->merge_bh_size) { 1328 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1329 " 0 now\n"); 1330 tape->merge_bh_size = 0; 1331 } 1332 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1333 if (!tape->merge_bh) 1334 return -ENOMEM; 1335 tape->chrdev_dir = IDETAPE_DIR_READ; 1336 1337 /* 1338 * Issue a read 0 command to ensure that DSC handshake is 1339 * switched from completion mode to buffer available mode. 1340 * No point in issuing this if DSC overlap isn't supported, some 1341 * drives (Seagate STT3401A) will return an error. 1342 */ 1343 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1344 bytes_read = idetape_queue_rw_tail(drive, 1345 REQ_IDETAPE_READ, 0, 1346 tape->merge_bh); 1347 if (bytes_read < 0) { 1348 ide_tape_kfree_buffer(tape); 1349 tape->merge_bh = NULL; 1350 tape->chrdev_dir = IDETAPE_DIR_NONE; 1351 return bytes_read; 1352 } 1353 } 1354 } 1355 1356 return 0; 1357} 1358 1359/* called from idetape_chrdev_read() to service a chrdev read request. */ 1360static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1361{ 1362 idetape_tape_t *tape = drive->driver_data; 1363 1364 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1365 1366 /* If we are at a filemark, return a read length of 0 */ 1367 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1368 return 0; 1369 1370 idetape_init_read(drive); 1371 1372 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1373 tape->merge_bh); 1374} 1375 1376static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1377{ 1378 idetape_tape_t *tape = drive->driver_data; 1379 struct idetape_bh *bh; 1380 int blocks; 1381 1382 while (bcount) { 1383 unsigned int count; 1384 1385 bh = tape->merge_bh; 1386 count = min(tape->buffer_size, bcount); 1387 bcount -= count; 1388 blocks = count / tape->blk_size; 1389 while (count) { 1390 atomic_set(&bh->b_count, 1391 min(count, (unsigned int)bh->b_size)); 1392 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1393 count -= atomic_read(&bh->b_count); 1394 bh = bh->b_reqnext; 1395 } 1396 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1397 tape->merge_bh); 1398 } 1399} 1400 1401/* 1402 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1403 * currently support only one partition. 1404 */ 1405static int idetape_rewind_tape(ide_drive_t *drive) 1406{ 1407 struct ide_tape_obj *tape = drive->driver_data; 1408 struct gendisk *disk = tape->disk; 1409 int retval; 1410 struct ide_atapi_pc pc; 1411 1412 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1413 1414 idetape_create_rewind_cmd(drive, &pc); 1415 retval = ide_queue_pc_tail(drive, disk, &pc); 1416 if (retval) 1417 return retval; 1418 1419 idetape_create_read_position_cmd(&pc); 1420 retval = ide_queue_pc_tail(drive, disk, &pc); 1421 if (retval) 1422 return retval; 1423 return 0; 1424} 1425 1426/* mtio.h compatible commands should be issued to the chrdev interface. */ 1427static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1428 unsigned long arg) 1429{ 1430 idetape_tape_t *tape = drive->driver_data; 1431 void __user *argp = (void __user *)arg; 1432 1433 struct idetape_config { 1434 int dsc_rw_frequency; 1435 int dsc_media_access_frequency; 1436 int nr_stages; 1437 } config; 1438 1439 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1440 1441 switch (cmd) { 1442 case 0x0340: 1443 if (copy_from_user(&config, argp, sizeof(config))) 1444 return -EFAULT; 1445 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1446 break; 1447 case 0x0350: 1448 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1449 config.nr_stages = 1; 1450 if (copy_to_user(argp, &config, sizeof(config))) 1451 return -EFAULT; 1452 break; 1453 default: 1454 return -EIO; 1455 } 1456 return 0; 1457} 1458 1459static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1460 int mt_count) 1461{ 1462 idetape_tape_t *tape = drive->driver_data; 1463 struct gendisk *disk = tape->disk; 1464 struct ide_atapi_pc pc; 1465 int retval, count = 0; 1466 int sprev = !!(tape->caps[4] & 0x20); 1467 1468 if (mt_count == 0) 1469 return 0; 1470 if (MTBSF == mt_op || MTBSFM == mt_op) { 1471 if (!sprev) 1472 return -EIO; 1473 mt_count = -mt_count; 1474 } 1475 1476 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1477 tape->merge_bh_size = 0; 1478 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1479 ++count; 1480 ide_tape_discard_merge_buffer(drive, 0); 1481 } 1482 1483 switch (mt_op) { 1484 case MTFSF: 1485 case MTBSF: 1486 idetape_create_space_cmd(&pc, mt_count - count, 1487 IDETAPE_SPACE_OVER_FILEMARK); 1488 return ide_queue_pc_tail(drive, disk, &pc); 1489 case MTFSFM: 1490 case MTBSFM: 1491 if (!sprev) 1492 return -EIO; 1493 retval = idetape_space_over_filemarks(drive, MTFSF, 1494 mt_count - count); 1495 if (retval) 1496 return retval; 1497 count = (MTBSFM == mt_op ? 1 : -1); 1498 return idetape_space_over_filemarks(drive, MTFSF, count); 1499 default: 1500 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1501 mt_op); 1502 return -EIO; 1503 } 1504} 1505 1506/* 1507 * Our character device read / write functions. 1508 * 1509 * The tape is optimized to maximize throughput when it is transferring an 1510 * integral number of the "continuous transfer limit", which is a parameter of 1511 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1512 * 1513 * As of version 1.3 of the driver, the character device provides an abstract 1514 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1515 * same backup/restore procedure is supported. The driver will internally 1516 * convert the requests to the recommended transfer unit, so that an unmatch 1517 * between the user's block size to the recommended size will only result in a 1518 * (slightly) increased driver overhead, but will no longer hit performance. 1519 * This is not applicable to Onstream. 1520 */ 1521static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1522 size_t count, loff_t *ppos) 1523{ 1524 struct ide_tape_obj *tape = file->private_data; 1525 ide_drive_t *drive = tape->drive; 1526 ssize_t bytes_read, temp, actually_read = 0, rc; 1527 ssize_t ret = 0; 1528 u16 ctl = *(u16 *)&tape->caps[12]; 1529 1530 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1531 1532 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1533 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1534 if (count > tape->blk_size && 1535 (count % tape->blk_size) == 0) 1536 tape->user_bs_factor = count / tape->blk_size; 1537 } 1538 rc = idetape_init_read(drive); 1539 if (rc < 0) 1540 return rc; 1541 if (count == 0) 1542 return (0); 1543 if (tape->merge_bh_size) { 1544 actually_read = min((unsigned int)(tape->merge_bh_size), 1545 (unsigned int)count); 1546 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1547 ret = -EFAULT; 1548 buf += actually_read; 1549 tape->merge_bh_size -= actually_read; 1550 count -= actually_read; 1551 } 1552 while (count >= tape->buffer_size) { 1553 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1554 if (bytes_read <= 0) 1555 goto finish; 1556 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1557 ret = -EFAULT; 1558 buf += bytes_read; 1559 count -= bytes_read; 1560 actually_read += bytes_read; 1561 } 1562 if (count) { 1563 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1564 if (bytes_read <= 0) 1565 goto finish; 1566 temp = min((unsigned long)count, (unsigned long)bytes_read); 1567 if (idetape_copy_stage_to_user(tape, buf, temp)) 1568 ret = -EFAULT; 1569 actually_read += temp; 1570 tape->merge_bh_size = bytes_read-temp; 1571 } 1572finish: 1573 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1574 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1575 1576 idetape_space_over_filemarks(drive, MTFSF, 1); 1577 return 0; 1578 } 1579 1580 return ret ? ret : actually_read; 1581} 1582 1583static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1584 size_t count, loff_t *ppos) 1585{ 1586 struct ide_tape_obj *tape = file->private_data; 1587 ide_drive_t *drive = tape->drive; 1588 ssize_t actually_written = 0; 1589 ssize_t ret = 0; 1590 u16 ctl = *(u16 *)&tape->caps[12]; 1591 1592 /* The drive is write protected. */ 1593 if (tape->write_prot) 1594 return -EACCES; 1595 1596 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1597 1598 /* Initialize write operation */ 1599 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1600 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1601 ide_tape_discard_merge_buffer(drive, 1); 1602 if (tape->merge_bh || tape->merge_bh_size) { 1603 printk(KERN_ERR "ide-tape: merge_bh_size " 1604 "should be 0 now\n"); 1605 tape->merge_bh_size = 0; 1606 } 1607 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1608 if (!tape->merge_bh) 1609 return -ENOMEM; 1610 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1611 idetape_init_merge_buffer(tape); 1612 1613 /* 1614 * Issue a write 0 command to ensure that DSC handshake is 1615 * switched from completion mode to buffer available mode. No 1616 * point in issuing this if DSC overlap isn't supported, some 1617 * drives (Seagate STT3401A) will return an error. 1618 */ 1619 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1620 ssize_t retval = idetape_queue_rw_tail(drive, 1621 REQ_IDETAPE_WRITE, 0, 1622 tape->merge_bh); 1623 if (retval < 0) { 1624 ide_tape_kfree_buffer(tape); 1625 tape->merge_bh = NULL; 1626 tape->chrdev_dir = IDETAPE_DIR_NONE; 1627 return retval; 1628 } 1629 } 1630 } 1631 if (count == 0) 1632 return (0); 1633 if (tape->merge_bh_size) { 1634 if (tape->merge_bh_size >= tape->buffer_size) { 1635 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1636 tape->merge_bh_size = 0; 1637 } 1638 actually_written = min((unsigned int) 1639 (tape->buffer_size - tape->merge_bh_size), 1640 (unsigned int)count); 1641 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1642 ret = -EFAULT; 1643 buf += actually_written; 1644 tape->merge_bh_size += actually_written; 1645 count -= actually_written; 1646 1647 if (tape->merge_bh_size == tape->buffer_size) { 1648 ssize_t retval; 1649 tape->merge_bh_size = 0; 1650 retval = idetape_add_chrdev_write_request(drive, ctl); 1651 if (retval <= 0) 1652 return (retval); 1653 } 1654 } 1655 while (count >= tape->buffer_size) { 1656 ssize_t retval; 1657 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1658 ret = -EFAULT; 1659 buf += tape->buffer_size; 1660 count -= tape->buffer_size; 1661 retval = idetape_add_chrdev_write_request(drive, ctl); 1662 actually_written += tape->buffer_size; 1663 if (retval <= 0) 1664 return (retval); 1665 } 1666 if (count) { 1667 actually_written += count; 1668 if (idetape_copy_stage_from_user(tape, buf, count)) 1669 ret = -EFAULT; 1670 tape->merge_bh_size += count; 1671 } 1672 return ret ? ret : actually_written; 1673} 1674 1675static int idetape_write_filemark(ide_drive_t *drive) 1676{ 1677 struct ide_tape_obj *tape = drive->driver_data; 1678 struct ide_atapi_pc pc; 1679 1680 /* Write a filemark */ 1681 idetape_create_write_filemark_cmd(drive, &pc, 1); 1682 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1683 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1684 return -EIO; 1685 } 1686 return 0; 1687} 1688 1689/* 1690 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1691 * requested. 1692 * 1693 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1694 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1695 * usually not supported. 1696 * 1697 * The following commands are currently not supported: 1698 * 1699 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1700 * MT_ST_WRITE_THRESHOLD. 1701 */ 1702static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1703{ 1704 idetape_tape_t *tape = drive->driver_data; 1705 struct gendisk *disk = tape->disk; 1706 struct ide_atapi_pc pc; 1707 int i, retval; 1708 1709 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1710 mt_op, mt_count); 1711 1712 switch (mt_op) { 1713 case MTFSF: 1714 case MTFSFM: 1715 case MTBSF: 1716 case MTBSFM: 1717 if (!mt_count) 1718 return 0; 1719 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1720 default: 1721 break; 1722 } 1723 1724 switch (mt_op) { 1725 case MTWEOF: 1726 if (tape->write_prot) 1727 return -EACCES; 1728 ide_tape_discard_merge_buffer(drive, 1); 1729 for (i = 0; i < mt_count; i++) { 1730 retval = idetape_write_filemark(drive); 1731 if (retval) 1732 return retval; 1733 } 1734 return 0; 1735 case MTREW: 1736 ide_tape_discard_merge_buffer(drive, 0); 1737 if (idetape_rewind_tape(drive)) 1738 return -EIO; 1739 return 0; 1740 case MTLOAD: 1741 ide_tape_discard_merge_buffer(drive, 0); 1742 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1743 case MTUNLOAD: 1744 case MTOFFL: 1745 /* 1746 * If door is locked, attempt to unlock before 1747 * attempting to eject. 1748 */ 1749 if (tape->door_locked) { 1750 if (!ide_set_media_lock(drive, disk, 0)) 1751 tape->door_locked = DOOR_UNLOCKED; 1752 } 1753 ide_tape_discard_merge_buffer(drive, 0); 1754 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); 1755 if (!retval) 1756 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1757 return retval; 1758 case MTNOP: 1759 ide_tape_discard_merge_buffer(drive, 0); 1760 return idetape_flush_tape_buffers(drive); 1761 case MTRETEN: 1762 ide_tape_discard_merge_buffer(drive, 0); 1763 return ide_do_start_stop(drive, disk, 1764 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1765 case MTEOM: 1766 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1767 return ide_queue_pc_tail(drive, disk, &pc); 1768 case MTERASE: 1769 (void)idetape_rewind_tape(drive); 1770 idetape_create_erase_cmd(&pc); 1771 return ide_queue_pc_tail(drive, disk, &pc); 1772 case MTSETBLK: 1773 if (mt_count) { 1774 if (mt_count < tape->blk_size || 1775 mt_count % tape->blk_size) 1776 return -EIO; 1777 tape->user_bs_factor = mt_count / tape->blk_size; 1778 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1779 } else 1780 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1781 return 0; 1782 case MTSEEK: 1783 ide_tape_discard_merge_buffer(drive, 0); 1784 return idetape_position_tape(drive, 1785 mt_count * tape->user_bs_factor, tape->partition, 0); 1786 case MTSETPART: 1787 ide_tape_discard_merge_buffer(drive, 0); 1788 return idetape_position_tape(drive, 0, mt_count, 0); 1789 case MTFSR: 1790 case MTBSR: 1791 case MTLOCK: 1792 retval = ide_set_media_lock(drive, disk, 1); 1793 if (retval) 1794 return retval; 1795 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1796 return 0; 1797 case MTUNLOCK: 1798 retval = ide_set_media_lock(drive, disk, 0); 1799 if (retval) 1800 return retval; 1801 tape->door_locked = DOOR_UNLOCKED; 1802 return 0; 1803 default: 1804 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1805 mt_op); 1806 return -EIO; 1807 } 1808} 1809 1810/* 1811 * Our character device ioctls. General mtio.h magnetic io commands are 1812 * supported here, and not in the corresponding block interface. Our own 1813 * ide-tape ioctls are supported on both interfaces. 1814 */ 1815static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1816 unsigned int cmd, unsigned long arg) 1817{ 1818 struct ide_tape_obj *tape = file->private_data; 1819 ide_drive_t *drive = tape->drive; 1820 struct mtop mtop; 1821 struct mtget mtget; 1822 struct mtpos mtpos; 1823 int block_offset = 0, position = tape->first_frame; 1824 void __user *argp = (void __user *)arg; 1825 1826 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1827 1828 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1829 ide_tape_flush_merge_buffer(drive); 1830 idetape_flush_tape_buffers(drive); 1831 } 1832 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1833 block_offset = tape->merge_bh_size / 1834 (tape->blk_size * tape->user_bs_factor); 1835 position = idetape_read_position(drive); 1836 if (position < 0) 1837 return -EIO; 1838 } 1839 switch (cmd) { 1840 case MTIOCTOP: 1841 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1842 return -EFAULT; 1843 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1844 case MTIOCGET: 1845 memset(&mtget, 0, sizeof(struct mtget)); 1846 mtget.mt_type = MT_ISSCSI2; 1847 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1848 mtget.mt_dsreg = 1849 ((tape->blk_size * tape->user_bs_factor) 1850 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1851 1852 if (tape->drv_write_prot) 1853 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1854 1855 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1856 return -EFAULT; 1857 return 0; 1858 case MTIOCPOS: 1859 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1860 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1861 return -EFAULT; 1862 return 0; 1863 default: 1864 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1865 ide_tape_discard_merge_buffer(drive, 1); 1866 return idetape_blkdev_ioctl(drive, cmd, arg); 1867 } 1868} 1869 1870/* 1871 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1872 * block size with the reported value. 1873 */ 1874static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1875{ 1876 idetape_tape_t *tape = drive->driver_data; 1877 struct ide_atapi_pc pc; 1878 1879 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1880 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1881 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1882 if (tape->blk_size == 0) { 1883 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1884 "block size, assuming 32k\n"); 1885 tape->blk_size = 32768; 1886 } 1887 return; 1888 } 1889 tape->blk_size = (pc.buf[4 + 5] << 16) + 1890 (pc.buf[4 + 6] << 8) + 1891 pc.buf[4 + 7]; 1892 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1893} 1894 1895static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1896{ 1897 unsigned int minor = iminor(inode), i = minor & ~0xc0; 1898 ide_drive_t *drive; 1899 idetape_tape_t *tape; 1900 int retval; 1901 1902 if (i >= MAX_HWIFS * MAX_DRIVES) 1903 return -ENXIO; 1904 1905 lock_kernel(); 1906 tape = ide_tape_chrdev_get(i); 1907 if (!tape) { 1908 unlock_kernel(); 1909 return -ENXIO; 1910 } 1911 1912 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1913 1914 /* 1915 * We really want to do nonseekable_open(inode, filp); here, but some 1916 * versions of tar incorrectly call lseek on tapes and bail out if that 1917 * fails. So we disallow pread() and pwrite(), but permit lseeks. 1918 */ 1919 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 1920 1921 drive = tape->drive; 1922 1923 filp->private_data = tape; 1924 1925 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 1926 retval = -EBUSY; 1927 goto out_put_tape; 1928 } 1929 1930 retval = idetape_wait_ready(drive, 60 * HZ); 1931 if (retval) { 1932 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1933 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 1934 goto out_put_tape; 1935 } 1936 1937 idetape_read_position(drive); 1938 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 1939 (void)idetape_rewind_tape(drive); 1940 1941 /* Read block size and write protect status from drive. */ 1942 ide_tape_get_bsize_from_bdesc(drive); 1943 1944 /* Set write protect flag if device is opened as read-only. */ 1945 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 1946 tape->write_prot = 1; 1947 else 1948 tape->write_prot = tape->drv_write_prot; 1949 1950 /* Make sure drive isn't write protected if user wants to write. */ 1951 if (tape->write_prot) { 1952 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 1953 (filp->f_flags & O_ACCMODE) == O_RDWR) { 1954 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1955 retval = -EROFS; 1956 goto out_put_tape; 1957 } 1958 } 1959 1960 /* Lock the tape drive door so user can't eject. */ 1961 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1962 if (!ide_set_media_lock(drive, tape->disk, 1)) { 1963 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 1964 tape->door_locked = DOOR_LOCKED; 1965 } 1966 } 1967 unlock_kernel(); 1968 return 0; 1969 1970out_put_tape: 1971 ide_tape_put(tape); 1972 unlock_kernel(); 1973 return retval; 1974} 1975 1976static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 1977{ 1978 idetape_tape_t *tape = drive->driver_data; 1979 1980 ide_tape_flush_merge_buffer(drive); 1981 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 1982 if (tape->merge_bh != NULL) { 1983 idetape_pad_zeros(drive, tape->blk_size * 1984 (tape->user_bs_factor - 1)); 1985 ide_tape_kfree_buffer(tape); 1986 tape->merge_bh = NULL; 1987 } 1988 idetape_write_filemark(drive); 1989 idetape_flush_tape_buffers(drive); 1990 idetape_flush_tape_buffers(drive); 1991} 1992 1993static int idetape_chrdev_release(struct inode *inode, struct file *filp) 1994{ 1995 struct ide_tape_obj *tape = filp->private_data; 1996 ide_drive_t *drive = tape->drive; 1997 unsigned int minor = iminor(inode); 1998 1999 lock_kernel(); 2000 tape = drive->driver_data; 2001 2002 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2003 2004 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2005 idetape_write_release(drive, minor); 2006 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2007 if (minor < 128) 2008 ide_tape_discard_merge_buffer(drive, 1); 2009 } 2010 2011 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 2012 (void) idetape_rewind_tape(drive); 2013 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2014 if (tape->door_locked == DOOR_LOCKED) { 2015 if (!ide_set_media_lock(drive, tape->disk, 0)) 2016 tape->door_locked = DOOR_UNLOCKED; 2017 } 2018 } 2019 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2020 ide_tape_put(tape); 2021 unlock_kernel(); 2022 return 0; 2023} 2024 2025static void idetape_get_inquiry_results(ide_drive_t *drive) 2026{ 2027 idetape_tape_t *tape = drive->driver_data; 2028 struct ide_atapi_pc pc; 2029 char fw_rev[4], vendor_id[8], product_id[16]; 2030 2031 idetape_create_inquiry_cmd(&pc); 2032 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2033 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2034 tape->name); 2035 return; 2036 } 2037 memcpy(vendor_id, &pc.buf[8], 8); 2038 memcpy(product_id, &pc.buf[16], 16); 2039 memcpy(fw_rev, &pc.buf[32], 4); 2040 2041 ide_fixstring(vendor_id, 8, 0); 2042 ide_fixstring(product_id, 16, 0); 2043 ide_fixstring(fw_rev, 4, 0); 2044 2045 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2046 drive->name, tape->name, vendor_id, product_id, fw_rev); 2047} 2048 2049/* 2050 * Ask the tape about its various parameters. In particular, we will adjust our 2051 * data transfer buffer size to the recommended value as returned by the tape. 2052 */ 2053static void idetape_get_mode_sense_results(ide_drive_t *drive) 2054{ 2055 idetape_tape_t *tape = drive->driver_data; 2056 struct ide_atapi_pc pc; 2057 u8 *caps; 2058 u8 speed, max_speed; 2059 2060 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2061 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2062 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2063 " some default values\n"); 2064 tape->blk_size = 512; 2065 put_unaligned(52, (u16 *)&tape->caps[12]); 2066 put_unaligned(540, (u16 *)&tape->caps[14]); 2067 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2068 return; 2069 } 2070 caps = pc.buf + 4 + pc.buf[3]; 2071 2072 /* convert to host order and save for later use */ 2073 speed = be16_to_cpup((__be16 *)&caps[14]); 2074 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2075 2076 *(u16 *)&caps[8] = max_speed; 2077 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2078 *(u16 *)&caps[14] = speed; 2079 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2080 2081 if (!speed) { 2082 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2083 "(assuming 650KB/sec)\n", drive->name); 2084 *(u16 *)&caps[14] = 650; 2085 } 2086 if (!max_speed) { 2087 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2088 "(assuming 650KB/sec)\n", drive->name); 2089 *(u16 *)&caps[8] = 650; 2090 } 2091 2092 memcpy(&tape->caps, caps, 20); 2093 2094 /* device lacks locking support according to capabilities page */ 2095 if ((caps[6] & 1) == 0) 2096 drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING; 2097 2098 if (caps[7] & 0x02) 2099 tape->blk_size = 512; 2100 else if (caps[7] & 0x04) 2101 tape->blk_size = 1024; 2102} 2103 2104#ifdef CONFIG_IDE_PROC_FS 2105#define ide_tape_devset_get(name, field) \ 2106static int get_##name(ide_drive_t *drive) \ 2107{ \ 2108 idetape_tape_t *tape = drive->driver_data; \ 2109 return tape->field; \ 2110} 2111 2112#define ide_tape_devset_set(name, field) \ 2113static int set_##name(ide_drive_t *drive, int arg) \ 2114{ \ 2115 idetape_tape_t *tape = drive->driver_data; \ 2116 tape->field = arg; \ 2117 return 0; \ 2118} 2119 2120#define ide_tape_devset_rw_field(_name, _field) \ 2121ide_tape_devset_get(_name, _field) \ 2122ide_tape_devset_set(_name, _field) \ 2123IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name) 2124 2125#define ide_tape_devset_r_field(_name, _field) \ 2126ide_tape_devset_get(_name, _field) \ 2127IDE_DEVSET(_name, 0, get_##_name, NULL) 2128 2129static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2130static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2131static int divf_buffer(ide_drive_t *drive) { return 2; } 2132static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2133 2134ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP); 2135 2136ide_tape_devset_rw_field(debug_mask, debug_mask); 2137ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq); 2138 2139ide_tape_devset_r_field(avg_speed, avg_speed); 2140ide_tape_devset_r_field(speed, caps[14]); 2141ide_tape_devset_r_field(buffer, caps[16]); 2142ide_tape_devset_r_field(buffer_size, buffer_size); 2143 2144static const struct ide_proc_devset idetape_settings[] = { 2145 __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), 2146 __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), 2147 __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), 2148 __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), 2149 __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), 2150 __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), 2151 __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2152 mulf_tdsc, divf_tdsc), 2153 { NULL }, 2154}; 2155#endif 2156 2157/* 2158 * The function below is called to: 2159 * 2160 * 1. Initialize our various state variables. 2161 * 2. Ask the tape for its capabilities. 2162 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2163 * is chosen based on the recommendation which we received in step 2. 2164 * 2165 * Note that at this point ide.c already assigned us an irq, so that we can 2166 * queue requests here and wait for their completion. 2167 */ 2168static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2169{ 2170 unsigned long t; 2171 int speed; 2172 int buffer_size; 2173 u16 *ctl = (u16 *)&tape->caps[12]; 2174 2175 drive->pc_callback = ide_tape_callback; 2176 drive->pc_update_buffers = idetape_update_buffers; 2177 drive->pc_io_buffers = ide_tape_io_buffers; 2178 2179 drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP; 2180 2181 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2182 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2183 tape->name); 2184 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2185 } 2186 2187 /* Seagate Travan drives do not support DSC overlap. */ 2188 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2189 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2190 2191 tape->minor = minor; 2192 tape->name[0] = 'h'; 2193 tape->name[1] = 't'; 2194 tape->name[2] = '0' + minor; 2195 tape->chrdev_dir = IDETAPE_DIR_NONE; 2196 2197 idetape_get_inquiry_results(drive); 2198 idetape_get_mode_sense_results(drive); 2199 ide_tape_get_bsize_from_bdesc(drive); 2200 tape->user_bs_factor = 1; 2201 tape->buffer_size = *ctl * tape->blk_size; 2202 while (tape->buffer_size > 0xffff) { 2203 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2204 *ctl /= 2; 2205 tape->buffer_size = *ctl * tape->blk_size; 2206 } 2207 buffer_size = tape->buffer_size; 2208 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2209 if (buffer_size % PAGE_SIZE) { 2210 tape->pages_per_buffer++; 2211 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2212 } 2213 2214 /* select the "best" DSC read/write polling freq */ 2215 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2216 2217 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2218 2219 /* 2220 * Ensure that the number we got makes sense; limit it within 2221 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2222 */ 2223 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2224 IDETAPE_DSC_RW_MAX); 2225 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2226 "%lums tDSC%s\n", 2227 drive->name, tape->name, *(u16 *)&tape->caps[14], 2228 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2229 tape->buffer_size / 1024, 2230 tape->best_dsc_rw_freq * 1000 / HZ, 2231 (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : ""); 2232 2233 ide_proc_register_driver(drive, tape->driver); 2234} 2235 2236static void ide_tape_remove(ide_drive_t *drive) 2237{ 2238 idetape_tape_t *tape = drive->driver_data; 2239 2240 ide_proc_unregister_driver(drive, tape->driver); 2241 device_del(&tape->dev); 2242 ide_unregister_region(tape->disk); 2243 2244 mutex_lock(&idetape_ref_mutex); 2245 put_device(&tape->dev); 2246 mutex_unlock(&idetape_ref_mutex); 2247} 2248 2249static void ide_tape_release(struct device *dev) 2250{ 2251 struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj); 2252 ide_drive_t *drive = tape->drive; 2253 struct gendisk *g = tape->disk; 2254 2255 BUG_ON(tape->merge_bh_size); 2256 2257 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2258 drive->driver_data = NULL; 2259 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2260 device_destroy(idetape_sysfs_class, 2261 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2262 idetape_devs[tape->minor] = NULL; 2263 g->private_data = NULL; 2264 put_disk(g); 2265 kfree(tape); 2266} 2267 2268#ifdef CONFIG_IDE_PROC_FS 2269static int proc_idetape_read_name 2270 (char *page, char **start, off_t off, int count, int *eof, void *data) 2271{ 2272 ide_drive_t *drive = (ide_drive_t *) data; 2273 idetape_tape_t *tape = drive->driver_data; 2274 char *out = page; 2275 int len; 2276 2277 len = sprintf(out, "%s\n", tape->name); 2278 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2279} 2280 2281static ide_proc_entry_t idetape_proc[] = { 2282 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2283 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2284 { NULL, 0, NULL, NULL } 2285}; 2286 2287static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive) 2288{ 2289 return idetape_proc; 2290} 2291 2292static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive) 2293{ 2294 return idetape_settings; 2295} 2296#endif 2297 2298static int ide_tape_probe(ide_drive_t *); 2299 2300static struct ide_driver idetape_driver = { 2301 .gen_driver = { 2302 .owner = THIS_MODULE, 2303 .name = "ide-tape", 2304 .bus = &ide_bus_type, 2305 }, 2306 .probe = ide_tape_probe, 2307 .remove = ide_tape_remove, 2308 .version = IDETAPE_VERSION, 2309 .do_request = idetape_do_request, 2310 .end_request = idetape_end_request, 2311#ifdef CONFIG_IDE_PROC_FS 2312 .proc_entries = ide_tape_proc_entries, 2313 .proc_devsets = ide_tape_proc_devsets, 2314#endif 2315}; 2316 2317/* Our character device supporting functions, passed to register_chrdev. */ 2318static const struct file_operations idetape_fops = { 2319 .owner = THIS_MODULE, 2320 .read = idetape_chrdev_read, 2321 .write = idetape_chrdev_write, 2322 .ioctl = idetape_chrdev_ioctl, 2323 .open = idetape_chrdev_open, 2324 .release = idetape_chrdev_release, 2325}; 2326 2327static int idetape_open(struct block_device *bdev, fmode_t mode) 2328{ 2329 struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk); 2330 2331 if (!tape) 2332 return -ENXIO; 2333 2334 return 0; 2335} 2336 2337static int idetape_release(struct gendisk *disk, fmode_t mode) 2338{ 2339 struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj); 2340 2341 ide_tape_put(tape); 2342 return 0; 2343} 2344 2345static int idetape_ioctl(struct block_device *bdev, fmode_t mode, 2346 unsigned int cmd, unsigned long arg) 2347{ 2348 struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj); 2349 ide_drive_t *drive = tape->drive; 2350 int err = generic_ide_ioctl(drive, bdev, cmd, arg); 2351 if (err == -EINVAL) 2352 err = idetape_blkdev_ioctl(drive, cmd, arg); 2353 return err; 2354} 2355 2356static struct block_device_operations idetape_block_ops = { 2357 .owner = THIS_MODULE, 2358 .open = idetape_open, 2359 .release = idetape_release, 2360 .locked_ioctl = idetape_ioctl, 2361}; 2362 2363static int ide_tape_probe(ide_drive_t *drive) 2364{ 2365 idetape_tape_t *tape; 2366 struct gendisk *g; 2367 int minor; 2368 2369 if (!strstr("ide-tape", drive->driver_req)) 2370 goto failed; 2371 2372 if (drive->media != ide_tape) 2373 goto failed; 2374 2375 if ((drive->dev_flags & IDE_DFLAG_ID_READ) && 2376 ide_check_atapi_device(drive, DRV_NAME) == 0) { 2377 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2378 " the driver\n", drive->name); 2379 goto failed; 2380 } 2381 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2382 if (tape == NULL) { 2383 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2384 drive->name); 2385 goto failed; 2386 } 2387 2388 g = alloc_disk(1 << PARTN_BITS); 2389 if (!g) 2390 goto out_free_tape; 2391 2392 ide_init_disk(g, drive); 2393 2394 tape->dev.parent = &drive->gendev; 2395 tape->dev.release = ide_tape_release; 2396 dev_set_name(&tape->dev, dev_name(&drive->gendev)); 2397 2398 if (device_register(&tape->dev)) 2399 goto out_free_disk; 2400 2401 tape->drive = drive; 2402 tape->driver = &idetape_driver; 2403 tape->disk = g; 2404 2405 g->private_data = &tape->driver; 2406 2407 drive->driver_data = tape; 2408 2409 mutex_lock(&idetape_ref_mutex); 2410 for (minor = 0; idetape_devs[minor]; minor++) 2411 ; 2412 idetape_devs[minor] = tape; 2413 mutex_unlock(&idetape_ref_mutex); 2414 2415 idetape_setup(drive, tape, minor); 2416 2417 device_create(idetape_sysfs_class, &drive->gendev, 2418 MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name); 2419 device_create(idetape_sysfs_class, &drive->gendev, 2420 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2421 "n%s", tape->name); 2422 2423 g->fops = &idetape_block_ops; 2424 ide_register_region(g); 2425 2426 return 0; 2427 2428out_free_disk: 2429 put_disk(g); 2430out_free_tape: 2431 kfree(tape); 2432failed: 2433 return -ENODEV; 2434} 2435 2436static void __exit idetape_exit(void) 2437{ 2438 driver_unregister(&idetape_driver.gen_driver); 2439 class_destroy(idetape_sysfs_class); 2440 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2441} 2442 2443static int __init idetape_init(void) 2444{ 2445 int error = 1; 2446 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2447 if (IS_ERR(idetape_sysfs_class)) { 2448 idetape_sysfs_class = NULL; 2449 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2450 error = -EBUSY; 2451 goto out; 2452 } 2453 2454 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2455 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2456 " interface\n"); 2457 error = -EBUSY; 2458 goto out_free_class; 2459 } 2460 2461 error = driver_register(&idetape_driver.gen_driver); 2462 if (error) 2463 goto out_free_driver; 2464 2465 return 0; 2466 2467out_free_driver: 2468 driver_unregister(&idetape_driver.gen_driver); 2469out_free_class: 2470 class_destroy(idetape_sysfs_class); 2471out: 2472 return error; 2473} 2474 2475MODULE_ALIAS("ide:*m-tape*"); 2476module_init(idetape_init); 2477module_exit(idetape_exit); 2478MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2479MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2480MODULE_LICENSE("GPL"); 2481