ide-tape.c revision 8fed43684174b68f04d01d1210fd00536af790df
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 /* 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 device *); 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 get_device(&tape->dev); 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 put_device(&tape->dev); 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 get_device(&tape->dev); 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 = drive->hwif->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->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 port 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 = drive->hwif->rq; 588 589 ide_stall_queue(drive, tape->dsc_poll_freq); 590} 591 592static void ide_tape_handle_dsc(ide_drive_t *drive) 593{ 594 idetape_tape_t *tape = drive->driver_data; 595 596 /* Media access command */ 597 tape->dsc_polling_start = jiffies; 598 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 599 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 600 /* Allow ide.c to handle other requests */ 601 idetape_postpone_request(drive); 602} 603 604static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 605 unsigned int bcount, int write) 606{ 607 if (write) 608 idetape_output_buffers(drive, pc, bcount); 609 else 610 idetape_input_buffers(drive, pc, bcount); 611 612 return bcount; 613} 614 615/* 616 * Packet Command Interface 617 * 618 * The current Packet Command is available in drive->pc, and will not change 619 * until we finish handling it. Each packet command is associated with a 620 * callback function that will be called when the command is finished. 621 * 622 * The handling will be done in three stages: 623 * 624 * 1. idetape_issue_pc will send the packet command to the drive, and will set 625 * the interrupt handler to ide_pc_intr. 626 * 627 * 2. On each interrupt, ide_pc_intr will be called. This step will be 628 * repeated until the device signals us that no more interrupts will be issued. 629 * 630 * 3. ATAPI Tape media access commands have immediate status with a delayed 631 * process. In case of a successful initiation of a media access packet command, 632 * the DSC bit will be set when the actual execution of the command is finished. 633 * Since the tape drive will not issue an interrupt, we have to poll for this 634 * event. In this case, we define the request as "low priority request" by 635 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 636 * exit the driver. 637 * 638 * ide.c will then give higher priority to requests which originate from the 639 * other device, until will change rq_status to RQ_ACTIVE. 640 * 641 * 4. When the packet command is finished, it will be checked for errors. 642 * 643 * 5. In case an error was found, we queue a request sense packet command in 644 * front of the request queue and retry the operation up to 645 * IDETAPE_MAX_PC_RETRIES times. 646 * 647 * 6. In case no error was found, or we decided to give up and not to retry 648 * again, the callback function will be called and then we will handle the next 649 * request. 650 */ 651 652static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 653 struct ide_atapi_pc *pc) 654{ 655 idetape_tape_t *tape = drive->driver_data; 656 657 if (drive->pc->c[0] == REQUEST_SENSE && 658 pc->c[0] == REQUEST_SENSE) { 659 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 660 "Two request sense in serial were issued\n"); 661 } 662 663 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 664 tape->failed_pc = pc; 665 666 /* Set the current packet command */ 667 drive->pc = pc; 668 669 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 670 (pc->flags & PC_FLAG_ABORT)) { 671 /* 672 * We will "abort" retrying a packet command in case legitimate 673 * error code was received (crossing a filemark, or end of the 674 * media, for example). 675 */ 676 if (!(pc->flags & PC_FLAG_ABORT)) { 677 if (!(pc->c[0] == TEST_UNIT_READY && 678 tape->sense_key == 2 && tape->asc == 4 && 679 (tape->ascq == 1 || tape->ascq == 8))) { 680 printk(KERN_ERR "ide-tape: %s: I/O error, " 681 "pc = %2x, key = %2x, " 682 "asc = %2x, ascq = %2x\n", 683 tape->name, pc->c[0], 684 tape->sense_key, tape->asc, 685 tape->ascq); 686 } 687 /* Giving up */ 688 pc->error = IDETAPE_ERROR_GENERAL; 689 } 690 tape->failed_pc = NULL; 691 drive->pc_callback(drive, 0); 692 return ide_stopped; 693 } 694 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 695 696 pc->retries++; 697 698 return ide_issue_pc(drive); 699} 700 701/* A mode sense command is used to "sense" tape parameters. */ 702static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 703{ 704 ide_init_pc(pc); 705 pc->c[0] = MODE_SENSE; 706 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 707 /* DBD = 1 - Don't return block descriptors */ 708 pc->c[1] = 8; 709 pc->c[2] = page_code; 710 /* 711 * Changed pc->c[3] to 0 (255 will at best return unused info). 712 * 713 * For SCSI this byte is defined as subpage instead of high byte 714 * of length and some IDE drives seem to interpret it this way 715 * and return an error when 255 is used. 716 */ 717 pc->c[3] = 0; 718 /* We will just discard data in that case */ 719 pc->c[4] = 255; 720 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 721 pc->req_xfer = 12; 722 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 723 pc->req_xfer = 24; 724 else 725 pc->req_xfer = 50; 726} 727 728static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 729{ 730 ide_hwif_t *hwif = drive->hwif; 731 idetape_tape_t *tape = drive->driver_data; 732 struct ide_atapi_pc *pc = drive->pc; 733 u8 stat; 734 735 stat = hwif->tp_ops->read_status(hwif); 736 737 if (stat & ATA_DSC) { 738 if (stat & ATA_ERR) { 739 /* Error detected */ 740 if (pc->c[0] != TEST_UNIT_READY) 741 printk(KERN_ERR "ide-tape: %s: I/O error, ", 742 tape->name); 743 /* Retry operation */ 744 ide_retry_pc(drive, tape->disk); 745 return ide_stopped; 746 } 747 pc->error = 0; 748 } else { 749 pc->error = IDETAPE_ERROR_GENERAL; 750 tape->failed_pc = NULL; 751 } 752 drive->pc_callback(drive, 0); 753 return ide_stopped; 754} 755 756static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 757 struct ide_atapi_pc *pc, struct request *rq, 758 u8 opcode) 759{ 760 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 761 unsigned int length = rq->current_nr_sectors; 762 763 ide_init_pc(pc); 764 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 765 pc->c[1] = 1; 766 pc->bh = bh; 767 pc->buf = NULL; 768 pc->buf_size = length * tape->blk_size; 769 pc->req_xfer = pc->buf_size; 770 if (pc->req_xfer == tape->buffer_size) 771 pc->flags |= PC_FLAG_DMA_OK; 772 773 if (opcode == READ_6) { 774 pc->c[0] = READ_6; 775 atomic_set(&bh->b_count, 0); 776 } else if (opcode == WRITE_6) { 777 pc->c[0] = WRITE_6; 778 pc->flags |= PC_FLAG_WRITING; 779 pc->b_data = bh->b_data; 780 pc->b_count = atomic_read(&bh->b_count); 781 } 782 783 memcpy(rq->cmd, pc->c, 12); 784} 785 786static ide_startstop_t idetape_do_request(ide_drive_t *drive, 787 struct request *rq, sector_t block) 788{ 789 ide_hwif_t *hwif = drive->hwif; 790 idetape_tape_t *tape = drive->driver_data; 791 struct ide_atapi_pc *pc = NULL; 792 struct request *postponed_rq = tape->postponed_rq; 793 u8 stat; 794 795 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 796 " current_nr_sectors: %u\n", 797 (unsigned long long)rq->sector, rq->nr_sectors, 798 rq->current_nr_sectors); 799 800 if (!blk_special_request(rq)) { 801 /* We do not support buffer cache originated requests. */ 802 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 803 "request queue (%d)\n", drive->name, rq->cmd_type); 804 ide_end_request(drive, 0, 0); 805 return ide_stopped; 806 } 807 808 /* Retry a failed packet command */ 809 if (tape->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { 810 pc = tape->failed_pc; 811 goto out; 812 } 813 814 if (postponed_rq != NULL) 815 if (rq != postponed_rq) { 816 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 817 "Two DSC requests were queued\n"); 818 idetape_end_request(drive, 0, 0); 819 return ide_stopped; 820 } 821 822 tape->postponed_rq = NULL; 823 824 /* 825 * If the tape is still busy, postpone our request and service 826 * the other device meanwhile. 827 */ 828 stat = hwif->tp_ops->read_status(hwif); 829 830 if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 && 831 (rq->cmd[13] & REQ_IDETAPE_PC2) == 0) 832 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 833 834 if (drive->dev_flags & IDE_DFLAG_POST_RESET) { 835 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 836 drive->dev_flags &= ~IDE_DFLAG_POST_RESET; 837 } 838 839 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 840 (stat & ATA_DSC) == 0) { 841 if (postponed_rq == NULL) { 842 tape->dsc_polling_start = jiffies; 843 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 844 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 845 } else if (time_after(jiffies, tape->dsc_timeout)) { 846 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 847 tape->name); 848 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 849 idetape_media_access_finished(drive); 850 return ide_stopped; 851 } else { 852 return ide_do_reset(drive); 853 } 854 } else if (time_after(jiffies, 855 tape->dsc_polling_start + 856 IDETAPE_DSC_MA_THRESHOLD)) 857 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 858 idetape_postpone_request(drive); 859 return ide_stopped; 860 } 861 if (rq->cmd[13] & REQ_IDETAPE_READ) { 862 pc = &tape->queued_pc; 863 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 864 goto out; 865 } 866 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 867 pc = &tape->queued_pc; 868 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 869 goto out; 870 } 871 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 872 pc = (struct ide_atapi_pc *) rq->buffer; 873 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 874 rq->cmd[13] |= REQ_IDETAPE_PC2; 875 goto out; 876 } 877 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 878 idetape_media_access_finished(drive); 879 return ide_stopped; 880 } 881 BUG(); 882 883out: 884 return idetape_issue_pc(drive, pc); 885} 886 887/* 888 * The function below uses __get_free_pages to allocate a data buffer of size 889 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 890 * much as possible. 891 * 892 * It returns a pointer to the newly allocated buffer, or NULL in case of 893 * failure. 894 */ 895static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 896 int full, int clear) 897{ 898 struct idetape_bh *prev_bh, *bh, *merge_bh; 899 int pages = tape->pages_per_buffer; 900 unsigned int order, b_allocd; 901 char *b_data = NULL; 902 903 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 904 bh = merge_bh; 905 if (bh == NULL) 906 goto abort; 907 908 order = fls(pages) - 1; 909 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 910 if (!bh->b_data) 911 goto abort; 912 b_allocd = (1 << order) * PAGE_SIZE; 913 pages &= (order-1); 914 915 if (clear) 916 memset(bh->b_data, 0, b_allocd); 917 bh->b_reqnext = NULL; 918 bh->b_size = b_allocd; 919 atomic_set(&bh->b_count, full ? bh->b_size : 0); 920 921 while (pages) { 922 order = fls(pages) - 1; 923 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 924 if (!b_data) 925 goto abort; 926 b_allocd = (1 << order) * PAGE_SIZE; 927 928 if (clear) 929 memset(b_data, 0, b_allocd); 930 931 /* newly allocated page frames below buffer header or ...*/ 932 if (bh->b_data == b_data + b_allocd) { 933 bh->b_size += b_allocd; 934 bh->b_data -= b_allocd; 935 if (full) 936 atomic_add(b_allocd, &bh->b_count); 937 continue; 938 } 939 /* they are above the header */ 940 if (b_data == bh->b_data + bh->b_size) { 941 bh->b_size += b_allocd; 942 if (full) 943 atomic_add(b_allocd, &bh->b_count); 944 continue; 945 } 946 prev_bh = bh; 947 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 948 if (!bh) { 949 free_pages((unsigned long) b_data, order); 950 goto abort; 951 } 952 bh->b_reqnext = NULL; 953 bh->b_data = b_data; 954 bh->b_size = b_allocd; 955 atomic_set(&bh->b_count, full ? bh->b_size : 0); 956 prev_bh->b_reqnext = bh; 957 958 pages &= (order-1); 959 } 960 961 bh->b_size -= tape->excess_bh_size; 962 if (full) 963 atomic_sub(tape->excess_bh_size, &bh->b_count); 964 return merge_bh; 965abort: 966 ide_tape_kfree_buffer(tape); 967 return NULL; 968} 969 970static int idetape_copy_stage_from_user(idetape_tape_t *tape, 971 const char __user *buf, int n) 972{ 973 struct idetape_bh *bh = tape->bh; 974 int count; 975 int ret = 0; 976 977 while (n) { 978 if (bh == NULL) { 979 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 980 __func__); 981 return 1; 982 } 983 count = min((unsigned int) 984 (bh->b_size - atomic_read(&bh->b_count)), 985 (unsigned int)n); 986 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 987 count)) 988 ret = 1; 989 n -= count; 990 atomic_add(count, &bh->b_count); 991 buf += count; 992 if (atomic_read(&bh->b_count) == bh->b_size) { 993 bh = bh->b_reqnext; 994 if (bh) 995 atomic_set(&bh->b_count, 0); 996 } 997 } 998 tape->bh = bh; 999 return ret; 1000} 1001 1002static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1003 int n) 1004{ 1005 struct idetape_bh *bh = tape->bh; 1006 int count; 1007 int ret = 0; 1008 1009 while (n) { 1010 if (bh == NULL) { 1011 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1012 __func__); 1013 return 1; 1014 } 1015 count = min(tape->b_count, n); 1016 if (copy_to_user(buf, tape->b_data, count)) 1017 ret = 1; 1018 n -= count; 1019 tape->b_data += count; 1020 tape->b_count -= count; 1021 buf += count; 1022 if (!tape->b_count) { 1023 bh = bh->b_reqnext; 1024 tape->bh = bh; 1025 if (bh) { 1026 tape->b_data = bh->b_data; 1027 tape->b_count = atomic_read(&bh->b_count); 1028 } 1029 } 1030 } 1031 return ret; 1032} 1033 1034static void idetape_init_merge_buffer(idetape_tape_t *tape) 1035{ 1036 struct idetape_bh *bh = tape->merge_bh; 1037 tape->bh = tape->merge_bh; 1038 1039 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1040 atomic_set(&bh->b_count, 0); 1041 else { 1042 tape->b_data = bh->b_data; 1043 tape->b_count = atomic_read(&bh->b_count); 1044 } 1045} 1046 1047/* 1048 * Write a filemark if write_filemark=1. Flush the device buffers without 1049 * writing a filemark otherwise. 1050 */ 1051static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1052 struct ide_atapi_pc *pc, int write_filemark) 1053{ 1054 ide_init_pc(pc); 1055 pc->c[0] = WRITE_FILEMARKS; 1056 pc->c[4] = write_filemark; 1057 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1058} 1059 1060static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1061{ 1062 idetape_tape_t *tape = drive->driver_data; 1063 struct gendisk *disk = tape->disk; 1064 int load_attempted = 0; 1065 1066 /* Wait for the tape to become ready */ 1067 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1068 timeout += jiffies; 1069 while (time_before(jiffies, timeout)) { 1070 if (ide_do_test_unit_ready(drive, disk) == 0) 1071 return 0; 1072 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1073 || (tape->asc == 0x3A)) { 1074 /* no media */ 1075 if (load_attempted) 1076 return -ENOMEDIUM; 1077 ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1078 load_attempted = 1; 1079 /* not about to be ready */ 1080 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1081 (tape->ascq == 1 || tape->ascq == 8))) 1082 return -EIO; 1083 msleep(100); 1084 } 1085 return -EIO; 1086} 1087 1088static int idetape_flush_tape_buffers(ide_drive_t *drive) 1089{ 1090 struct ide_tape_obj *tape = drive->driver_data; 1091 struct ide_atapi_pc pc; 1092 int rc; 1093 1094 idetape_create_write_filemark_cmd(drive, &pc, 0); 1095 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1096 if (rc) 1097 return rc; 1098 idetape_wait_ready(drive, 60 * 5 * HZ); 1099 return 0; 1100} 1101 1102static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1103{ 1104 ide_init_pc(pc); 1105 pc->c[0] = READ_POSITION; 1106 pc->req_xfer = 20; 1107} 1108 1109static int idetape_read_position(ide_drive_t *drive) 1110{ 1111 idetape_tape_t *tape = drive->driver_data; 1112 struct ide_atapi_pc pc; 1113 int position; 1114 1115 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1116 1117 idetape_create_read_position_cmd(&pc); 1118 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1119 return -1; 1120 position = tape->first_frame; 1121 return position; 1122} 1123 1124static void idetape_create_locate_cmd(ide_drive_t *drive, 1125 struct ide_atapi_pc *pc, 1126 unsigned int block, u8 partition, int skip) 1127{ 1128 ide_init_pc(pc); 1129 pc->c[0] = POSITION_TO_ELEMENT; 1130 pc->c[1] = 2; 1131 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1132 pc->c[8] = partition; 1133 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1134} 1135 1136static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1137{ 1138 idetape_tape_t *tape = drive->driver_data; 1139 1140 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1141 return; 1142 1143 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1144 tape->merge_bh_size = 0; 1145 if (tape->merge_bh != NULL) { 1146 ide_tape_kfree_buffer(tape); 1147 tape->merge_bh = NULL; 1148 } 1149 1150 tape->chrdev_dir = IDETAPE_DIR_NONE; 1151} 1152 1153/* 1154 * Position the tape to the requested block using the LOCATE packet command. 1155 * A READ POSITION command is then issued to check where we are positioned. Like 1156 * all higher level operations, we queue the commands at the tail of the request 1157 * queue and wait for their completion. 1158 */ 1159static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1160 u8 partition, int skip) 1161{ 1162 idetape_tape_t *tape = drive->driver_data; 1163 struct gendisk *disk = tape->disk; 1164 int retval; 1165 struct ide_atapi_pc pc; 1166 1167 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1168 __ide_tape_discard_merge_buffer(drive); 1169 idetape_wait_ready(drive, 60 * 5 * HZ); 1170 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1171 retval = ide_queue_pc_tail(drive, disk, &pc); 1172 if (retval) 1173 return (retval); 1174 1175 idetape_create_read_position_cmd(&pc); 1176 return ide_queue_pc_tail(drive, disk, &pc); 1177} 1178 1179static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1180 int restore_position) 1181{ 1182 idetape_tape_t *tape = drive->driver_data; 1183 int seek, position; 1184 1185 __ide_tape_discard_merge_buffer(drive); 1186 if (restore_position) { 1187 position = idetape_read_position(drive); 1188 seek = position > 0 ? position : 0; 1189 if (idetape_position_tape(drive, seek, 0, 0)) { 1190 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1191 " %s\n", tape->name, __func__); 1192 return; 1193 } 1194 } 1195} 1196 1197/* 1198 * Generate a read/write request for the block device interface and wait for it 1199 * to be serviced. 1200 */ 1201static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1202 struct idetape_bh *bh) 1203{ 1204 idetape_tape_t *tape = drive->driver_data; 1205 struct request *rq; 1206 int ret, errors; 1207 1208 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1209 1210 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1211 rq->cmd_type = REQ_TYPE_SPECIAL; 1212 rq->cmd[13] = cmd; 1213 rq->rq_disk = tape->disk; 1214 rq->special = (void *)bh; 1215 rq->sector = tape->first_frame; 1216 rq->nr_sectors = blocks; 1217 rq->current_nr_sectors = blocks; 1218 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1219 1220 errors = rq->errors; 1221 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1222 blk_put_request(rq); 1223 1224 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1225 return 0; 1226 1227 if (tape->merge_bh) 1228 idetape_init_merge_buffer(tape); 1229 if (errors == IDETAPE_ERROR_GENERAL) 1230 return -EIO; 1231 return ret; 1232} 1233 1234static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1235{ 1236 ide_init_pc(pc); 1237 pc->c[0] = INQUIRY; 1238 pc->c[4] = 254; 1239 pc->req_xfer = 254; 1240} 1241 1242static void idetape_create_rewind_cmd(ide_drive_t *drive, 1243 struct ide_atapi_pc *pc) 1244{ 1245 ide_init_pc(pc); 1246 pc->c[0] = REZERO_UNIT; 1247 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1248} 1249 1250static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1251{ 1252 ide_init_pc(pc); 1253 pc->c[0] = ERASE; 1254 pc->c[1] = 1; 1255 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1256} 1257 1258static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1259{ 1260 ide_init_pc(pc); 1261 pc->c[0] = SPACE; 1262 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1263 pc->c[1] = cmd; 1264 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1265} 1266 1267/* Queue up a character device originated write request. */ 1268static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1269{ 1270 idetape_tape_t *tape = drive->driver_data; 1271 1272 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1273 1274 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1275 blocks, tape->merge_bh); 1276} 1277 1278static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1279{ 1280 idetape_tape_t *tape = drive->driver_data; 1281 int blocks, min; 1282 struct idetape_bh *bh; 1283 1284 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1285 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1286 " but we are not writing.\n"); 1287 return; 1288 } 1289 if (tape->merge_bh_size > tape->buffer_size) { 1290 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1291 tape->merge_bh_size = tape->buffer_size; 1292 } 1293 if (tape->merge_bh_size) { 1294 blocks = tape->merge_bh_size / tape->blk_size; 1295 if (tape->merge_bh_size % tape->blk_size) { 1296 unsigned int i; 1297 1298 blocks++; 1299 i = tape->blk_size - tape->merge_bh_size % 1300 tape->blk_size; 1301 bh = tape->bh->b_reqnext; 1302 while (bh) { 1303 atomic_set(&bh->b_count, 0); 1304 bh = bh->b_reqnext; 1305 } 1306 bh = tape->bh; 1307 while (i) { 1308 if (bh == NULL) { 1309 printk(KERN_INFO "ide-tape: bug," 1310 " bh NULL\n"); 1311 break; 1312 } 1313 min = min(i, (unsigned int)(bh->b_size - 1314 atomic_read(&bh->b_count))); 1315 memset(bh->b_data + atomic_read(&bh->b_count), 1316 0, min); 1317 atomic_add(min, &bh->b_count); 1318 i -= min; 1319 bh = bh->b_reqnext; 1320 } 1321 } 1322 (void) idetape_add_chrdev_write_request(drive, blocks); 1323 tape->merge_bh_size = 0; 1324 } 1325 if (tape->merge_bh != NULL) { 1326 ide_tape_kfree_buffer(tape); 1327 tape->merge_bh = NULL; 1328 } 1329 tape->chrdev_dir = IDETAPE_DIR_NONE; 1330} 1331 1332static int idetape_init_read(ide_drive_t *drive) 1333{ 1334 idetape_tape_t *tape = drive->driver_data; 1335 int bytes_read; 1336 1337 /* Initialize read operation */ 1338 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1339 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1340 ide_tape_flush_merge_buffer(drive); 1341 idetape_flush_tape_buffers(drive); 1342 } 1343 if (tape->merge_bh || tape->merge_bh_size) { 1344 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1345 " 0 now\n"); 1346 tape->merge_bh_size = 0; 1347 } 1348 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1349 if (!tape->merge_bh) 1350 return -ENOMEM; 1351 tape->chrdev_dir = IDETAPE_DIR_READ; 1352 1353 /* 1354 * Issue a read 0 command to ensure that DSC handshake is 1355 * switched from completion mode to buffer available mode. 1356 * No point in issuing this if DSC overlap isn't supported, some 1357 * drives (Seagate STT3401A) will return an error. 1358 */ 1359 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1360 bytes_read = idetape_queue_rw_tail(drive, 1361 REQ_IDETAPE_READ, 0, 1362 tape->merge_bh); 1363 if (bytes_read < 0) { 1364 ide_tape_kfree_buffer(tape); 1365 tape->merge_bh = NULL; 1366 tape->chrdev_dir = IDETAPE_DIR_NONE; 1367 return bytes_read; 1368 } 1369 } 1370 } 1371 1372 return 0; 1373} 1374 1375/* called from idetape_chrdev_read() to service a chrdev read request. */ 1376static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1377{ 1378 idetape_tape_t *tape = drive->driver_data; 1379 1380 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1381 1382 /* If we are at a filemark, return a read length of 0 */ 1383 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1384 return 0; 1385 1386 idetape_init_read(drive); 1387 1388 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1389 tape->merge_bh); 1390} 1391 1392static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1393{ 1394 idetape_tape_t *tape = drive->driver_data; 1395 struct idetape_bh *bh; 1396 int blocks; 1397 1398 while (bcount) { 1399 unsigned int count; 1400 1401 bh = tape->merge_bh; 1402 count = min(tape->buffer_size, bcount); 1403 bcount -= count; 1404 blocks = count / tape->blk_size; 1405 while (count) { 1406 atomic_set(&bh->b_count, 1407 min(count, (unsigned int)bh->b_size)); 1408 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1409 count -= atomic_read(&bh->b_count); 1410 bh = bh->b_reqnext; 1411 } 1412 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1413 tape->merge_bh); 1414 } 1415} 1416 1417/* 1418 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1419 * currently support only one partition. 1420 */ 1421static int idetape_rewind_tape(ide_drive_t *drive) 1422{ 1423 struct ide_tape_obj *tape = drive->driver_data; 1424 struct gendisk *disk = tape->disk; 1425 int retval; 1426 struct ide_atapi_pc pc; 1427 1428 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1429 1430 idetape_create_rewind_cmd(drive, &pc); 1431 retval = ide_queue_pc_tail(drive, disk, &pc); 1432 if (retval) 1433 return retval; 1434 1435 idetape_create_read_position_cmd(&pc); 1436 retval = ide_queue_pc_tail(drive, disk, &pc); 1437 if (retval) 1438 return retval; 1439 return 0; 1440} 1441 1442/* mtio.h compatible commands should be issued to the chrdev interface. */ 1443static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1444 unsigned long arg) 1445{ 1446 idetape_tape_t *tape = drive->driver_data; 1447 void __user *argp = (void __user *)arg; 1448 1449 struct idetape_config { 1450 int dsc_rw_frequency; 1451 int dsc_media_access_frequency; 1452 int nr_stages; 1453 } config; 1454 1455 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1456 1457 switch (cmd) { 1458 case 0x0340: 1459 if (copy_from_user(&config, argp, sizeof(config))) 1460 return -EFAULT; 1461 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1462 break; 1463 case 0x0350: 1464 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1465 config.nr_stages = 1; 1466 if (copy_to_user(argp, &config, sizeof(config))) 1467 return -EFAULT; 1468 break; 1469 default: 1470 return -EIO; 1471 } 1472 return 0; 1473} 1474 1475static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1476 int mt_count) 1477{ 1478 idetape_tape_t *tape = drive->driver_data; 1479 struct gendisk *disk = tape->disk; 1480 struct ide_atapi_pc pc; 1481 int retval, count = 0; 1482 int sprev = !!(tape->caps[4] & 0x20); 1483 1484 if (mt_count == 0) 1485 return 0; 1486 if (MTBSF == mt_op || MTBSFM == mt_op) { 1487 if (!sprev) 1488 return -EIO; 1489 mt_count = -mt_count; 1490 } 1491 1492 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1493 tape->merge_bh_size = 0; 1494 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1495 ++count; 1496 ide_tape_discard_merge_buffer(drive, 0); 1497 } 1498 1499 switch (mt_op) { 1500 case MTFSF: 1501 case MTBSF: 1502 idetape_create_space_cmd(&pc, mt_count - count, 1503 IDETAPE_SPACE_OVER_FILEMARK); 1504 return ide_queue_pc_tail(drive, disk, &pc); 1505 case MTFSFM: 1506 case MTBSFM: 1507 if (!sprev) 1508 return -EIO; 1509 retval = idetape_space_over_filemarks(drive, MTFSF, 1510 mt_count - count); 1511 if (retval) 1512 return retval; 1513 count = (MTBSFM == mt_op ? 1 : -1); 1514 return idetape_space_over_filemarks(drive, MTFSF, count); 1515 default: 1516 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1517 mt_op); 1518 return -EIO; 1519 } 1520} 1521 1522/* 1523 * Our character device read / write functions. 1524 * 1525 * The tape is optimized to maximize throughput when it is transferring an 1526 * integral number of the "continuous transfer limit", which is a parameter of 1527 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1528 * 1529 * As of version 1.3 of the driver, the character device provides an abstract 1530 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1531 * same backup/restore procedure is supported. The driver will internally 1532 * convert the requests to the recommended transfer unit, so that an unmatch 1533 * between the user's block size to the recommended size will only result in a 1534 * (slightly) increased driver overhead, but will no longer hit performance. 1535 * This is not applicable to Onstream. 1536 */ 1537static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1538 size_t count, loff_t *ppos) 1539{ 1540 struct ide_tape_obj *tape = file->private_data; 1541 ide_drive_t *drive = tape->drive; 1542 ssize_t bytes_read, temp, actually_read = 0, rc; 1543 ssize_t ret = 0; 1544 u16 ctl = *(u16 *)&tape->caps[12]; 1545 1546 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1547 1548 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1549 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1550 if (count > tape->blk_size && 1551 (count % tape->blk_size) == 0) 1552 tape->user_bs_factor = count / tape->blk_size; 1553 } 1554 rc = idetape_init_read(drive); 1555 if (rc < 0) 1556 return rc; 1557 if (count == 0) 1558 return (0); 1559 if (tape->merge_bh_size) { 1560 actually_read = min((unsigned int)(tape->merge_bh_size), 1561 (unsigned int)count); 1562 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1563 ret = -EFAULT; 1564 buf += actually_read; 1565 tape->merge_bh_size -= actually_read; 1566 count -= actually_read; 1567 } 1568 while (count >= tape->buffer_size) { 1569 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1570 if (bytes_read <= 0) 1571 goto finish; 1572 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1573 ret = -EFAULT; 1574 buf += bytes_read; 1575 count -= bytes_read; 1576 actually_read += bytes_read; 1577 } 1578 if (count) { 1579 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1580 if (bytes_read <= 0) 1581 goto finish; 1582 temp = min((unsigned long)count, (unsigned long)bytes_read); 1583 if (idetape_copy_stage_to_user(tape, buf, temp)) 1584 ret = -EFAULT; 1585 actually_read += temp; 1586 tape->merge_bh_size = bytes_read-temp; 1587 } 1588finish: 1589 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1590 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1591 1592 idetape_space_over_filemarks(drive, MTFSF, 1); 1593 return 0; 1594 } 1595 1596 return ret ? ret : actually_read; 1597} 1598 1599static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1600 size_t count, loff_t *ppos) 1601{ 1602 struct ide_tape_obj *tape = file->private_data; 1603 ide_drive_t *drive = tape->drive; 1604 ssize_t actually_written = 0; 1605 ssize_t ret = 0; 1606 u16 ctl = *(u16 *)&tape->caps[12]; 1607 1608 /* The drive is write protected. */ 1609 if (tape->write_prot) 1610 return -EACCES; 1611 1612 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1613 1614 /* Initialize write operation */ 1615 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1616 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1617 ide_tape_discard_merge_buffer(drive, 1); 1618 if (tape->merge_bh || tape->merge_bh_size) { 1619 printk(KERN_ERR "ide-tape: merge_bh_size " 1620 "should be 0 now\n"); 1621 tape->merge_bh_size = 0; 1622 } 1623 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1624 if (!tape->merge_bh) 1625 return -ENOMEM; 1626 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1627 idetape_init_merge_buffer(tape); 1628 1629 /* 1630 * Issue a write 0 command to ensure that DSC handshake is 1631 * switched from completion mode to buffer available mode. No 1632 * point in issuing this if DSC overlap isn't supported, some 1633 * drives (Seagate STT3401A) will return an error. 1634 */ 1635 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1636 ssize_t retval = idetape_queue_rw_tail(drive, 1637 REQ_IDETAPE_WRITE, 0, 1638 tape->merge_bh); 1639 if (retval < 0) { 1640 ide_tape_kfree_buffer(tape); 1641 tape->merge_bh = NULL; 1642 tape->chrdev_dir = IDETAPE_DIR_NONE; 1643 return retval; 1644 } 1645 } 1646 } 1647 if (count == 0) 1648 return (0); 1649 if (tape->merge_bh_size) { 1650 if (tape->merge_bh_size >= tape->buffer_size) { 1651 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1652 tape->merge_bh_size = 0; 1653 } 1654 actually_written = min((unsigned int) 1655 (tape->buffer_size - tape->merge_bh_size), 1656 (unsigned int)count); 1657 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1658 ret = -EFAULT; 1659 buf += actually_written; 1660 tape->merge_bh_size += actually_written; 1661 count -= actually_written; 1662 1663 if (tape->merge_bh_size == tape->buffer_size) { 1664 ssize_t retval; 1665 tape->merge_bh_size = 0; 1666 retval = idetape_add_chrdev_write_request(drive, ctl); 1667 if (retval <= 0) 1668 return (retval); 1669 } 1670 } 1671 while (count >= tape->buffer_size) { 1672 ssize_t retval; 1673 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1674 ret = -EFAULT; 1675 buf += tape->buffer_size; 1676 count -= tape->buffer_size; 1677 retval = idetape_add_chrdev_write_request(drive, ctl); 1678 actually_written += tape->buffer_size; 1679 if (retval <= 0) 1680 return (retval); 1681 } 1682 if (count) { 1683 actually_written += count; 1684 if (idetape_copy_stage_from_user(tape, buf, count)) 1685 ret = -EFAULT; 1686 tape->merge_bh_size += count; 1687 } 1688 return ret ? ret : actually_written; 1689} 1690 1691static int idetape_write_filemark(ide_drive_t *drive) 1692{ 1693 struct ide_tape_obj *tape = drive->driver_data; 1694 struct ide_atapi_pc pc; 1695 1696 /* Write a filemark */ 1697 idetape_create_write_filemark_cmd(drive, &pc, 1); 1698 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1699 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1700 return -EIO; 1701 } 1702 return 0; 1703} 1704 1705/* 1706 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1707 * requested. 1708 * 1709 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1710 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1711 * usually not supported. 1712 * 1713 * The following commands are currently not supported: 1714 * 1715 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1716 * MT_ST_WRITE_THRESHOLD. 1717 */ 1718static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1719{ 1720 idetape_tape_t *tape = drive->driver_data; 1721 struct gendisk *disk = tape->disk; 1722 struct ide_atapi_pc pc; 1723 int i, retval; 1724 1725 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1726 mt_op, mt_count); 1727 1728 switch (mt_op) { 1729 case MTFSF: 1730 case MTFSFM: 1731 case MTBSF: 1732 case MTBSFM: 1733 if (!mt_count) 1734 return 0; 1735 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1736 default: 1737 break; 1738 } 1739 1740 switch (mt_op) { 1741 case MTWEOF: 1742 if (tape->write_prot) 1743 return -EACCES; 1744 ide_tape_discard_merge_buffer(drive, 1); 1745 for (i = 0; i < mt_count; i++) { 1746 retval = idetape_write_filemark(drive); 1747 if (retval) 1748 return retval; 1749 } 1750 return 0; 1751 case MTREW: 1752 ide_tape_discard_merge_buffer(drive, 0); 1753 if (idetape_rewind_tape(drive)) 1754 return -EIO; 1755 return 0; 1756 case MTLOAD: 1757 ide_tape_discard_merge_buffer(drive, 0); 1758 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1759 case MTUNLOAD: 1760 case MTOFFL: 1761 /* 1762 * If door is locked, attempt to unlock before 1763 * attempting to eject. 1764 */ 1765 if (tape->door_locked) { 1766 if (!ide_set_media_lock(drive, disk, 0)) 1767 tape->door_locked = DOOR_UNLOCKED; 1768 } 1769 ide_tape_discard_merge_buffer(drive, 0); 1770 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); 1771 if (!retval) 1772 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1773 return retval; 1774 case MTNOP: 1775 ide_tape_discard_merge_buffer(drive, 0); 1776 return idetape_flush_tape_buffers(drive); 1777 case MTRETEN: 1778 ide_tape_discard_merge_buffer(drive, 0); 1779 return ide_do_start_stop(drive, disk, 1780 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1781 case MTEOM: 1782 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1783 return ide_queue_pc_tail(drive, disk, &pc); 1784 case MTERASE: 1785 (void)idetape_rewind_tape(drive); 1786 idetape_create_erase_cmd(&pc); 1787 return ide_queue_pc_tail(drive, disk, &pc); 1788 case MTSETBLK: 1789 if (mt_count) { 1790 if (mt_count < tape->blk_size || 1791 mt_count % tape->blk_size) 1792 return -EIO; 1793 tape->user_bs_factor = mt_count / tape->blk_size; 1794 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1795 } else 1796 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1797 return 0; 1798 case MTSEEK: 1799 ide_tape_discard_merge_buffer(drive, 0); 1800 return idetape_position_tape(drive, 1801 mt_count * tape->user_bs_factor, tape->partition, 0); 1802 case MTSETPART: 1803 ide_tape_discard_merge_buffer(drive, 0); 1804 return idetape_position_tape(drive, 0, mt_count, 0); 1805 case MTFSR: 1806 case MTBSR: 1807 case MTLOCK: 1808 retval = ide_set_media_lock(drive, disk, 1); 1809 if (retval) 1810 return retval; 1811 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1812 return 0; 1813 case MTUNLOCK: 1814 retval = ide_set_media_lock(drive, disk, 0); 1815 if (retval) 1816 return retval; 1817 tape->door_locked = DOOR_UNLOCKED; 1818 return 0; 1819 default: 1820 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1821 mt_op); 1822 return -EIO; 1823 } 1824} 1825 1826/* 1827 * Our character device ioctls. General mtio.h magnetic io commands are 1828 * supported here, and not in the corresponding block interface. Our own 1829 * ide-tape ioctls are supported on both interfaces. 1830 */ 1831static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1832 unsigned int cmd, unsigned long arg) 1833{ 1834 struct ide_tape_obj *tape = file->private_data; 1835 ide_drive_t *drive = tape->drive; 1836 struct mtop mtop; 1837 struct mtget mtget; 1838 struct mtpos mtpos; 1839 int block_offset = 0, position = tape->first_frame; 1840 void __user *argp = (void __user *)arg; 1841 1842 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1843 1844 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1845 ide_tape_flush_merge_buffer(drive); 1846 idetape_flush_tape_buffers(drive); 1847 } 1848 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1849 block_offset = tape->merge_bh_size / 1850 (tape->blk_size * tape->user_bs_factor); 1851 position = idetape_read_position(drive); 1852 if (position < 0) 1853 return -EIO; 1854 } 1855 switch (cmd) { 1856 case MTIOCTOP: 1857 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1858 return -EFAULT; 1859 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1860 case MTIOCGET: 1861 memset(&mtget, 0, sizeof(struct mtget)); 1862 mtget.mt_type = MT_ISSCSI2; 1863 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1864 mtget.mt_dsreg = 1865 ((tape->blk_size * tape->user_bs_factor) 1866 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1867 1868 if (tape->drv_write_prot) 1869 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1870 1871 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1872 return -EFAULT; 1873 return 0; 1874 case MTIOCPOS: 1875 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1876 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1877 return -EFAULT; 1878 return 0; 1879 default: 1880 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1881 ide_tape_discard_merge_buffer(drive, 1); 1882 return idetape_blkdev_ioctl(drive, cmd, arg); 1883 } 1884} 1885 1886/* 1887 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1888 * block size with the reported value. 1889 */ 1890static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1891{ 1892 idetape_tape_t *tape = drive->driver_data; 1893 struct ide_atapi_pc pc; 1894 1895 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1896 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1897 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1898 if (tape->blk_size == 0) { 1899 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1900 "block size, assuming 32k\n"); 1901 tape->blk_size = 32768; 1902 } 1903 return; 1904 } 1905 tape->blk_size = (pc.buf[4 + 5] << 16) + 1906 (pc.buf[4 + 6] << 8) + 1907 pc.buf[4 + 7]; 1908 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1909} 1910 1911static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1912{ 1913 unsigned int minor = iminor(inode), i = minor & ~0xc0; 1914 ide_drive_t *drive; 1915 idetape_tape_t *tape; 1916 int retval; 1917 1918 if (i >= MAX_HWIFS * MAX_DRIVES) 1919 return -ENXIO; 1920 1921 lock_kernel(); 1922 tape = ide_tape_chrdev_get(i); 1923 if (!tape) { 1924 unlock_kernel(); 1925 return -ENXIO; 1926 } 1927 1928 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1929 1930 /* 1931 * We really want to do nonseekable_open(inode, filp); here, but some 1932 * versions of tar incorrectly call lseek on tapes and bail out if that 1933 * fails. So we disallow pread() and pwrite(), but permit lseeks. 1934 */ 1935 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 1936 1937 drive = tape->drive; 1938 1939 filp->private_data = tape; 1940 1941 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 1942 retval = -EBUSY; 1943 goto out_put_tape; 1944 } 1945 1946 retval = idetape_wait_ready(drive, 60 * HZ); 1947 if (retval) { 1948 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1949 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 1950 goto out_put_tape; 1951 } 1952 1953 idetape_read_position(drive); 1954 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 1955 (void)idetape_rewind_tape(drive); 1956 1957 /* Read block size and write protect status from drive. */ 1958 ide_tape_get_bsize_from_bdesc(drive); 1959 1960 /* Set write protect flag if device is opened as read-only. */ 1961 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 1962 tape->write_prot = 1; 1963 else 1964 tape->write_prot = tape->drv_write_prot; 1965 1966 /* Make sure drive isn't write protected if user wants to write. */ 1967 if (tape->write_prot) { 1968 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 1969 (filp->f_flags & O_ACCMODE) == O_RDWR) { 1970 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1971 retval = -EROFS; 1972 goto out_put_tape; 1973 } 1974 } 1975 1976 /* Lock the tape drive door so user can't eject. */ 1977 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1978 if (!ide_set_media_lock(drive, tape->disk, 1)) { 1979 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 1980 tape->door_locked = DOOR_LOCKED; 1981 } 1982 } 1983 unlock_kernel(); 1984 return 0; 1985 1986out_put_tape: 1987 ide_tape_put(tape); 1988 unlock_kernel(); 1989 return retval; 1990} 1991 1992static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 1993{ 1994 idetape_tape_t *tape = drive->driver_data; 1995 1996 ide_tape_flush_merge_buffer(drive); 1997 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 1998 if (tape->merge_bh != NULL) { 1999 idetape_pad_zeros(drive, tape->blk_size * 2000 (tape->user_bs_factor - 1)); 2001 ide_tape_kfree_buffer(tape); 2002 tape->merge_bh = NULL; 2003 } 2004 idetape_write_filemark(drive); 2005 idetape_flush_tape_buffers(drive); 2006 idetape_flush_tape_buffers(drive); 2007} 2008 2009static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2010{ 2011 struct ide_tape_obj *tape = filp->private_data; 2012 ide_drive_t *drive = tape->drive; 2013 unsigned int minor = iminor(inode); 2014 2015 lock_kernel(); 2016 tape = drive->driver_data; 2017 2018 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2019 2020 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2021 idetape_write_release(drive, minor); 2022 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2023 if (minor < 128) 2024 ide_tape_discard_merge_buffer(drive, 1); 2025 } 2026 2027 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 2028 (void) idetape_rewind_tape(drive); 2029 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2030 if (tape->door_locked == DOOR_LOCKED) { 2031 if (!ide_set_media_lock(drive, tape->disk, 0)) 2032 tape->door_locked = DOOR_UNLOCKED; 2033 } 2034 } 2035 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2036 ide_tape_put(tape); 2037 unlock_kernel(); 2038 return 0; 2039} 2040 2041static void idetape_get_inquiry_results(ide_drive_t *drive) 2042{ 2043 idetape_tape_t *tape = drive->driver_data; 2044 struct ide_atapi_pc pc; 2045 char fw_rev[4], vendor_id[8], product_id[16]; 2046 2047 idetape_create_inquiry_cmd(&pc); 2048 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2049 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2050 tape->name); 2051 return; 2052 } 2053 memcpy(vendor_id, &pc.buf[8], 8); 2054 memcpy(product_id, &pc.buf[16], 16); 2055 memcpy(fw_rev, &pc.buf[32], 4); 2056 2057 ide_fixstring(vendor_id, 8, 0); 2058 ide_fixstring(product_id, 16, 0); 2059 ide_fixstring(fw_rev, 4, 0); 2060 2061 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2062 drive->name, tape->name, vendor_id, product_id, fw_rev); 2063} 2064 2065/* 2066 * Ask the tape about its various parameters. In particular, we will adjust our 2067 * data transfer buffer size to the recommended value as returned by the tape. 2068 */ 2069static void idetape_get_mode_sense_results(ide_drive_t *drive) 2070{ 2071 idetape_tape_t *tape = drive->driver_data; 2072 struct ide_atapi_pc pc; 2073 u8 *caps; 2074 u8 speed, max_speed; 2075 2076 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2077 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2078 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2079 " some default values\n"); 2080 tape->blk_size = 512; 2081 put_unaligned(52, (u16 *)&tape->caps[12]); 2082 put_unaligned(540, (u16 *)&tape->caps[14]); 2083 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2084 return; 2085 } 2086 caps = pc.buf + 4 + pc.buf[3]; 2087 2088 /* convert to host order and save for later use */ 2089 speed = be16_to_cpup((__be16 *)&caps[14]); 2090 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2091 2092 *(u16 *)&caps[8] = max_speed; 2093 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2094 *(u16 *)&caps[14] = speed; 2095 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2096 2097 if (!speed) { 2098 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2099 "(assuming 650KB/sec)\n", drive->name); 2100 *(u16 *)&caps[14] = 650; 2101 } 2102 if (!max_speed) { 2103 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2104 "(assuming 650KB/sec)\n", drive->name); 2105 *(u16 *)&caps[8] = 650; 2106 } 2107 2108 memcpy(&tape->caps, caps, 20); 2109 2110 /* device lacks locking support according to capabilities page */ 2111 if ((caps[6] & 1) == 0) 2112 drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING; 2113 2114 if (caps[7] & 0x02) 2115 tape->blk_size = 512; 2116 else if (caps[7] & 0x04) 2117 tape->blk_size = 1024; 2118} 2119 2120#ifdef CONFIG_IDE_PROC_FS 2121#define ide_tape_devset_get(name, field) \ 2122static int get_##name(ide_drive_t *drive) \ 2123{ \ 2124 idetape_tape_t *tape = drive->driver_data; \ 2125 return tape->field; \ 2126} 2127 2128#define ide_tape_devset_set(name, field) \ 2129static int set_##name(ide_drive_t *drive, int arg) \ 2130{ \ 2131 idetape_tape_t *tape = drive->driver_data; \ 2132 tape->field = arg; \ 2133 return 0; \ 2134} 2135 2136#define ide_tape_devset_rw_field(_name, _field) \ 2137ide_tape_devset_get(_name, _field) \ 2138ide_tape_devset_set(_name, _field) \ 2139IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name) 2140 2141#define ide_tape_devset_r_field(_name, _field) \ 2142ide_tape_devset_get(_name, _field) \ 2143IDE_DEVSET(_name, 0, get_##_name, NULL) 2144 2145static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2146static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2147static int divf_buffer(ide_drive_t *drive) { return 2; } 2148static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2149 2150ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP); 2151 2152ide_tape_devset_rw_field(debug_mask, debug_mask); 2153ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq); 2154 2155ide_tape_devset_r_field(avg_speed, avg_speed); 2156ide_tape_devset_r_field(speed, caps[14]); 2157ide_tape_devset_r_field(buffer, caps[16]); 2158ide_tape_devset_r_field(buffer_size, buffer_size); 2159 2160static const struct ide_proc_devset idetape_settings[] = { 2161 __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), 2162 __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), 2163 __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), 2164 __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), 2165 __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), 2166 __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), 2167 __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2168 mulf_tdsc, divf_tdsc), 2169 { 0 }, 2170}; 2171#endif 2172 2173/* 2174 * The function below is called to: 2175 * 2176 * 1. Initialize our various state variables. 2177 * 2. Ask the tape for its capabilities. 2178 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2179 * is chosen based on the recommendation which we received in step 2. 2180 * 2181 * Note that at this point ide.c already assigned us an irq, so that we can 2182 * queue requests here and wait for their completion. 2183 */ 2184static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2185{ 2186 unsigned long t; 2187 int speed; 2188 int buffer_size; 2189 u16 *ctl = (u16 *)&tape->caps[12]; 2190 2191 drive->pc_callback = ide_tape_callback; 2192 drive->pc_update_buffers = idetape_update_buffers; 2193 drive->pc_io_buffers = ide_tape_io_buffers; 2194 2195 spin_lock_init(&tape->lock); 2196 2197 drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP; 2198 2199 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2200 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2201 tape->name); 2202 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2203 } 2204 2205 /* Seagate Travan drives do not support DSC overlap. */ 2206 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2207 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2208 2209 tape->minor = minor; 2210 tape->name[0] = 'h'; 2211 tape->name[1] = 't'; 2212 tape->name[2] = '0' + minor; 2213 tape->chrdev_dir = IDETAPE_DIR_NONE; 2214 2215 idetape_get_inquiry_results(drive); 2216 idetape_get_mode_sense_results(drive); 2217 ide_tape_get_bsize_from_bdesc(drive); 2218 tape->user_bs_factor = 1; 2219 tape->buffer_size = *ctl * tape->blk_size; 2220 while (tape->buffer_size > 0xffff) { 2221 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2222 *ctl /= 2; 2223 tape->buffer_size = *ctl * tape->blk_size; 2224 } 2225 buffer_size = tape->buffer_size; 2226 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2227 if (buffer_size % PAGE_SIZE) { 2228 tape->pages_per_buffer++; 2229 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2230 } 2231 2232 /* select the "best" DSC read/write polling freq */ 2233 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2234 2235 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2236 2237 /* 2238 * Ensure that the number we got makes sense; limit it within 2239 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2240 */ 2241 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2242 IDETAPE_DSC_RW_MAX); 2243 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2244 "%lums tDSC%s\n", 2245 drive->name, tape->name, *(u16 *)&tape->caps[14], 2246 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2247 tape->buffer_size / 1024, 2248 tape->best_dsc_rw_freq * 1000 / HZ, 2249 (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : ""); 2250 2251 ide_proc_register_driver(drive, tape->driver); 2252} 2253 2254static void ide_tape_remove(ide_drive_t *drive) 2255{ 2256 idetape_tape_t *tape = drive->driver_data; 2257 2258 ide_proc_unregister_driver(drive, tape->driver); 2259 device_del(&tape->dev); 2260 ide_unregister_region(tape->disk); 2261 2262 mutex_lock(&idetape_ref_mutex); 2263 put_device(&tape->dev); 2264 mutex_unlock(&idetape_ref_mutex); 2265} 2266 2267static void ide_tape_release(struct device *dev) 2268{ 2269 struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj); 2270 ide_drive_t *drive = tape->drive; 2271 struct gendisk *g = tape->disk; 2272 2273 BUG_ON(tape->merge_bh_size); 2274 2275 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2276 drive->driver_data = NULL; 2277 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2278 device_destroy(idetape_sysfs_class, 2279 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2280 idetape_devs[tape->minor] = NULL; 2281 g->private_data = NULL; 2282 put_disk(g); 2283 kfree(tape); 2284} 2285 2286#ifdef CONFIG_IDE_PROC_FS 2287static int proc_idetape_read_name 2288 (char *page, char **start, off_t off, int count, int *eof, void *data) 2289{ 2290 ide_drive_t *drive = (ide_drive_t *) data; 2291 idetape_tape_t *tape = drive->driver_data; 2292 char *out = page; 2293 int len; 2294 2295 len = sprintf(out, "%s\n", tape->name); 2296 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2297} 2298 2299static ide_proc_entry_t idetape_proc[] = { 2300 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2301 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2302 { NULL, 0, NULL, NULL } 2303}; 2304 2305static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive) 2306{ 2307 return idetape_proc; 2308} 2309 2310static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive) 2311{ 2312 return idetape_settings; 2313} 2314#endif 2315 2316static int ide_tape_probe(ide_drive_t *); 2317 2318static struct ide_driver idetape_driver = { 2319 .gen_driver = { 2320 .owner = THIS_MODULE, 2321 .name = "ide-tape", 2322 .bus = &ide_bus_type, 2323 }, 2324 .probe = ide_tape_probe, 2325 .remove = ide_tape_remove, 2326 .version = IDETAPE_VERSION, 2327 .do_request = idetape_do_request, 2328 .end_request = idetape_end_request, 2329#ifdef CONFIG_IDE_PROC_FS 2330 .proc_entries = ide_tape_proc_entries, 2331 .proc_devsets = ide_tape_proc_devsets, 2332#endif 2333}; 2334 2335/* Our character device supporting functions, passed to register_chrdev. */ 2336static const struct file_operations idetape_fops = { 2337 .owner = THIS_MODULE, 2338 .read = idetape_chrdev_read, 2339 .write = idetape_chrdev_write, 2340 .ioctl = idetape_chrdev_ioctl, 2341 .open = idetape_chrdev_open, 2342 .release = idetape_chrdev_release, 2343}; 2344 2345static int idetape_open(struct block_device *bdev, fmode_t mode) 2346{ 2347 struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk); 2348 2349 if (!tape) 2350 return -ENXIO; 2351 2352 return 0; 2353} 2354 2355static int idetape_release(struct gendisk *disk, fmode_t mode) 2356{ 2357 struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj); 2358 2359 ide_tape_put(tape); 2360 return 0; 2361} 2362 2363static int idetape_ioctl(struct block_device *bdev, fmode_t mode, 2364 unsigned int cmd, unsigned long arg) 2365{ 2366 struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj); 2367 ide_drive_t *drive = tape->drive; 2368 int err = generic_ide_ioctl(drive, bdev, cmd, arg); 2369 if (err == -EINVAL) 2370 err = idetape_blkdev_ioctl(drive, cmd, arg); 2371 return err; 2372} 2373 2374static struct block_device_operations idetape_block_ops = { 2375 .owner = THIS_MODULE, 2376 .open = idetape_open, 2377 .release = idetape_release, 2378 .locked_ioctl = idetape_ioctl, 2379}; 2380 2381static int ide_tape_probe(ide_drive_t *drive) 2382{ 2383 idetape_tape_t *tape; 2384 struct gendisk *g; 2385 int minor; 2386 2387 if (!strstr("ide-tape", drive->driver_req)) 2388 goto failed; 2389 2390 if (drive->media != ide_tape) 2391 goto failed; 2392 2393 if ((drive->dev_flags & IDE_DFLAG_ID_READ) && 2394 ide_check_atapi_device(drive, DRV_NAME) == 0) { 2395 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2396 " the driver\n", drive->name); 2397 goto failed; 2398 } 2399 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2400 if (tape == NULL) { 2401 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2402 drive->name); 2403 goto failed; 2404 } 2405 2406 g = alloc_disk(1 << PARTN_BITS); 2407 if (!g) 2408 goto out_free_tape; 2409 2410 ide_init_disk(g, drive); 2411 2412 tape->dev.parent = &drive->gendev; 2413 tape->dev.release = ide_tape_release; 2414 dev_set_name(&tape->dev, dev_name(&drive->gendev)); 2415 2416 if (device_register(&tape->dev)) 2417 goto out_free_disk; 2418 2419 tape->drive = drive; 2420 tape->driver = &idetape_driver; 2421 tape->disk = g; 2422 2423 g->private_data = &tape->driver; 2424 2425 drive->driver_data = tape; 2426 2427 mutex_lock(&idetape_ref_mutex); 2428 for (minor = 0; idetape_devs[minor]; minor++) 2429 ; 2430 idetape_devs[minor] = tape; 2431 mutex_unlock(&idetape_ref_mutex); 2432 2433 idetape_setup(drive, tape, minor); 2434 2435 device_create(idetape_sysfs_class, &drive->gendev, 2436 MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name); 2437 device_create(idetape_sysfs_class, &drive->gendev, 2438 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2439 "n%s", tape->name); 2440 2441 g->fops = &idetape_block_ops; 2442 ide_register_region(g); 2443 2444 return 0; 2445 2446out_free_disk: 2447 put_disk(g); 2448out_free_tape: 2449 kfree(tape); 2450failed: 2451 return -ENODEV; 2452} 2453 2454static void __exit idetape_exit(void) 2455{ 2456 driver_unregister(&idetape_driver.gen_driver); 2457 class_destroy(idetape_sysfs_class); 2458 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2459} 2460 2461static int __init idetape_init(void) 2462{ 2463 int error = 1; 2464 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2465 if (IS_ERR(idetape_sysfs_class)) { 2466 idetape_sysfs_class = NULL; 2467 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2468 error = -EBUSY; 2469 goto out; 2470 } 2471 2472 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2473 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2474 " interface\n"); 2475 error = -EBUSY; 2476 goto out_free_class; 2477 } 2478 2479 error = driver_register(&idetape_driver.gen_driver); 2480 if (error) 2481 goto out_free_driver; 2482 2483 return 0; 2484 2485out_free_driver: 2486 driver_unregister(&idetape_driver.gen_driver); 2487out_free_class: 2488 class_destroy(idetape_sysfs_class); 2489out: 2490 return error; 2491} 2492 2493MODULE_ALIAS("ide:*m-tape*"); 2494module_init(idetape_init); 2495module_exit(idetape_exit); 2496MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2497MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2498MODULE_LICENSE("GPL"); 2499