ide-tape.c revision 67c56364df843fb9e3ed1af014b8fbe4b22ff25d
1/* 2 * IDE ATAPI streaming tape driver. 3 * 4 * Copyright (C) 1995-1999 Gadi Oxman <gadio@netvision.net.il> 5 * Copyright (C) 2003-2005 Bartlomiej Zolnierkiewicz 6 * 7 * This driver was constructed as a student project in the software laboratory 8 * of the faculty of electrical engineering in the Technion - Israel's 9 * Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David. 10 * 11 * It is hereby placed under the terms of the GNU general public license. 12 * (See linux/COPYING). 13 * 14 * For a historical changelog see 15 * Documentation/ide/ChangeLog.ide-tape.1995-2002 16 */ 17 18#define DRV_NAME "ide-tape" 19 20#define IDETAPE_VERSION "1.20" 21 22#include <linux/module.h> 23#include <linux/types.h> 24#include <linux/string.h> 25#include <linux/kernel.h> 26#include <linux/delay.h> 27#include <linux/timer.h> 28#include <linux/mm.h> 29#include <linux/interrupt.h> 30#include <linux/jiffies.h> 31#include <linux/major.h> 32#include <linux/errno.h> 33#include <linux/genhd.h> 34#include <linux/slab.h> 35#include <linux/pci.h> 36#include <linux/ide.h> 37#include <linux/smp_lock.h> 38#include <linux/completion.h> 39#include <linux/bitops.h> 40#include <linux/mutex.h> 41#include <scsi/scsi.h> 42 43#include <asm/byteorder.h> 44#include <linux/irq.h> 45#include <linux/uaccess.h> 46#include <linux/io.h> 47#include <asm/unaligned.h> 48#include <linux/mtio.h> 49 50enum { 51 /* output errors only */ 52 DBG_ERR = (1 << 0), 53 /* output all sense key/asc */ 54 DBG_SENSE = (1 << 1), 55 /* info regarding all chrdev-related procedures */ 56 DBG_CHRDEV = (1 << 2), 57 /* all remaining procedures */ 58 DBG_PROCS = (1 << 3), 59}; 60 61/* define to see debug info */ 62#define IDETAPE_DEBUG_LOG 0 63 64#if IDETAPE_DEBUG_LOG 65#define debug_log(lvl, fmt, args...) \ 66{ \ 67 if (tape->debug_mask & lvl) \ 68 printk(KERN_INFO "ide-tape: " fmt, ## args); \ 69} 70#else 71#define debug_log(lvl, fmt, args...) do {} while (0) 72#endif 73 74/**************************** Tunable parameters *****************************/ 75/* 76 * After each failed packet command we issue a request sense command and retry 77 * the packet command IDETAPE_MAX_PC_RETRIES times. 78 * 79 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries. 80 */ 81#define IDETAPE_MAX_PC_RETRIES 3 82 83/* 84 * The following parameter is used to select the point in the internal tape fifo 85 * in which we will start to refill the buffer. Decreasing the following 86 * parameter will improve the system's latency and interactive response, while 87 * using a high value might improve system throughput. 88 */ 89#define IDETAPE_FIFO_THRESHOLD 2 90 91/* 92 * DSC polling parameters. 93 * 94 * Polling for DSC (a single bit in the status register) is a very important 95 * function in ide-tape. There are two cases in which we poll for DSC: 96 * 97 * 1. Before a read/write packet command, to ensure that we can transfer data 98 * from/to the tape's data buffers, without causing an actual media access. 99 * In case the tape is not ready yet, we take out our request from the device 100 * request queue, so that ide.c could service requests from the other device 101 * on the same interface in the meantime. 102 * 103 * 2. After the successful initialization of a "media access packet command", 104 * which is a command that can take a long time to complete (the interval can 105 * range from several seconds to even an hour). Again, we postpone our request 106 * in the middle to free the bus for the other device. The polling frequency 107 * here should be lower than the read/write frequency since those media access 108 * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST 109 * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD 110 * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min). 111 * 112 * We also set a timeout for the timer, in case something goes wrong. The 113 * timeout should be longer then the maximum execution time of a tape operation. 114 */ 115 116/* DSC timings. */ 117#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */ 118#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */ 119#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */ 120#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */ 121#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */ 122#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */ 123#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */ 124 125/*************************** End of tunable parameters ***********************/ 126 127/* tape directions */ 128enum { 129 IDETAPE_DIR_NONE = (1 << 0), 130 IDETAPE_DIR_READ = (1 << 1), 131 IDETAPE_DIR_WRITE = (1 << 2), 132}; 133 134struct idetape_bh { 135 u32 b_size; 136 atomic_t b_count; 137 struct idetape_bh *b_reqnext; 138 char *b_data; 139}; 140 141/* Tape door status */ 142#define DOOR_UNLOCKED 0 143#define DOOR_LOCKED 1 144#define DOOR_EXPLICITLY_LOCKED 2 145 146/* Some defines for the SPACE command */ 147#define IDETAPE_SPACE_OVER_FILEMARK 1 148#define IDETAPE_SPACE_TO_EOD 3 149 150/* Some defines for the LOAD UNLOAD command */ 151#define IDETAPE_LU_LOAD_MASK 1 152#define IDETAPE_LU_RETENSION_MASK 2 153#define IDETAPE_LU_EOT_MASK 4 154 155/* Error codes returned in rq->errors to the higher part of the driver. */ 156#define IDETAPE_ERROR_GENERAL 101 157#define IDETAPE_ERROR_FILEMARK 102 158#define IDETAPE_ERROR_EOD 103 159 160/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 161#define IDETAPE_BLOCK_DESCRIPTOR 0 162#define IDETAPE_CAPABILITIES_PAGE 0x2a 163 164/* 165 * Most of our global data which we need to save even as we leave the driver due 166 * to an interrupt or a timer event is stored in the struct defined below. 167 */ 168typedef struct ide_tape_obj { 169 ide_drive_t *drive; 170 ide_driver_t *driver; 171 struct gendisk *disk; 172 struct kref kref; 173 174 /* 175 * failed_pc points to the last failed packet command, or contains 176 * NULL if we do not need to retry any packet command. This is 177 * required since an additional packet command is needed before the 178 * retry, to get detailed information on what went wrong. 179 */ 180 /* Last failed packet command */ 181 struct ide_atapi_pc *failed_pc; 182 /* used by REQ_IDETAPE_{READ,WRITE} requests */ 183 struct ide_atapi_pc queued_pc; 184 185 /* 186 * DSC polling variables. 187 * 188 * While polling for DSC we use postponed_rq to postpone the current 189 * request so that ide.c will be able to service pending requests on the 190 * other device. Note that at most we will have only one DSC (usually 191 * data transfer) request in the device request queue. 192 */ 193 struct request *postponed_rq; 194 /* The time in which we started polling for DSC */ 195 unsigned long dsc_polling_start; 196 /* Timer used to poll for dsc */ 197 struct timer_list dsc_timer; 198 /* Read/Write dsc polling frequency */ 199 unsigned long best_dsc_rw_freq; 200 unsigned long dsc_poll_freq; 201 unsigned long dsc_timeout; 202 203 /* Read position information */ 204 u8 partition; 205 /* Current block */ 206 unsigned int first_frame; 207 208 /* Last error information */ 209 u8 sense_key, asc, ascq; 210 211 /* Character device operation */ 212 unsigned int minor; 213 /* device name */ 214 char name[4]; 215 /* Current character device data transfer direction */ 216 u8 chrdev_dir; 217 218 /* tape block size, usually 512 or 1024 bytes */ 219 unsigned short blk_size; 220 int user_bs_factor; 221 222 /* Copy of the tape's Capabilities and Mechanical Page */ 223 u8 caps[20]; 224 225 /* 226 * Active data transfer request parameters. 227 * 228 * At most, there is only one ide-tape originated data transfer request 229 * in the device request queue. This allows ide.c to easily service 230 * requests from the other device when we postpone our active request. 231 */ 232 233 /* Data buffer size chosen based on the tape's recommendation */ 234 int buffer_size; 235 /* merge buffer */ 236 struct idetape_bh *merge_bh; 237 /* size of the merge buffer */ 238 int merge_bh_size; 239 /* pointer to current buffer head within the merge buffer */ 240 struct idetape_bh *bh; 241 char *b_data; 242 int b_count; 243 244 int pages_per_buffer; 245 /* Wasted space in each stage */ 246 int excess_bh_size; 247 248 /* protects the ide-tape queue */ 249 spinlock_t lock; 250 251 /* Measures average tape speed */ 252 unsigned long avg_time; 253 int avg_size; 254 int avg_speed; 255 256 /* the door is currently locked */ 257 int door_locked; 258 /* the tape hardware is write protected */ 259 char drv_write_prot; 260 /* the tape is write protected (hardware or opened as read-only) */ 261 char write_prot; 262 263 u32 debug_mask; 264} idetape_tape_t; 265 266static DEFINE_MUTEX(idetape_ref_mutex); 267 268static struct class *idetape_sysfs_class; 269 270#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref) 271 272#define ide_tape_g(disk) \ 273 container_of((disk)->private_data, struct ide_tape_obj, driver) 274 275static void ide_tape_release(struct kref *); 276 277static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 278{ 279 struct ide_tape_obj *tape = NULL; 280 281 mutex_lock(&idetape_ref_mutex); 282 tape = ide_tape_g(disk); 283 if (tape) { 284 if (ide_device_get(tape->drive)) 285 tape = NULL; 286 else 287 kref_get(&tape->kref); 288 } 289 mutex_unlock(&idetape_ref_mutex); 290 return tape; 291} 292 293static void ide_tape_put(struct ide_tape_obj *tape) 294{ 295 ide_drive_t *drive = tape->drive; 296 297 mutex_lock(&idetape_ref_mutex); 298 kref_put(&tape->kref, ide_tape_release); 299 ide_device_put(drive); 300 mutex_unlock(&idetape_ref_mutex); 301} 302 303/* 304 * The variables below are used for the character device interface. Additional 305 * state variables are defined in our ide_drive_t structure. 306 */ 307static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES]; 308 309#define ide_tape_f(file) ((file)->private_data) 310 311static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 312{ 313 struct ide_tape_obj *tape = NULL; 314 315 mutex_lock(&idetape_ref_mutex); 316 tape = idetape_devs[i]; 317 if (tape) 318 kref_get(&tape->kref); 319 mutex_unlock(&idetape_ref_mutex); 320 return tape; 321} 322 323static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 324 unsigned int bcount) 325{ 326 struct idetape_bh *bh = pc->bh; 327 int count; 328 329 while (bcount) { 330 if (bh == NULL) { 331 printk(KERN_ERR "ide-tape: bh == NULL in " 332 "idetape_input_buffers\n"); 333 ide_pad_transfer(drive, 0, bcount); 334 return; 335 } 336 count = min( 337 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 338 bcount); 339 drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data + 340 atomic_read(&bh->b_count), count); 341 bcount -= count; 342 atomic_add(count, &bh->b_count); 343 if (atomic_read(&bh->b_count) == bh->b_size) { 344 bh = bh->b_reqnext; 345 if (bh) 346 atomic_set(&bh->b_count, 0); 347 } 348 } 349 pc->bh = bh; 350} 351 352static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 353 unsigned int bcount) 354{ 355 struct idetape_bh *bh = pc->bh; 356 int count; 357 358 while (bcount) { 359 if (bh == NULL) { 360 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 361 __func__); 362 return; 363 } 364 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 365 drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); 366 bcount -= count; 367 pc->b_data += count; 368 pc->b_count -= count; 369 if (!pc->b_count) { 370 bh = bh->b_reqnext; 371 pc->bh = bh; 372 if (bh) { 373 pc->b_data = bh->b_data; 374 pc->b_count = atomic_read(&bh->b_count); 375 } 376 } 377 } 378} 379 380static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) 381{ 382 struct idetape_bh *bh = pc->bh; 383 int count; 384 unsigned int bcount = pc->xferred; 385 386 if (pc->flags & PC_FLAG_WRITING) 387 return; 388 while (bcount) { 389 if (bh == NULL) { 390 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 391 __func__); 392 return; 393 } 394 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 395 atomic_set(&bh->b_count, count); 396 if (atomic_read(&bh->b_count) == bh->b_size) 397 bh = bh->b_reqnext; 398 bcount -= count; 399 } 400 pc->bh = bh; 401} 402 403/* 404 * called on each failed packet command retry to analyze the request sense. We 405 * currently do not utilize this information. 406 */ 407static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 408{ 409 idetape_tape_t *tape = drive->driver_data; 410 struct ide_atapi_pc *pc = tape->failed_pc; 411 412 tape->sense_key = sense[2] & 0xF; 413 tape->asc = sense[12]; 414 tape->ascq = sense[13]; 415 416 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 417 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 418 419 /* Correct pc->xferred by asking the tape. */ 420 if (pc->flags & PC_FLAG_DMA_ERROR) { 421 pc->xferred = pc->req_xfer - 422 tape->blk_size * 423 get_unaligned_be32(&sense[3]); 424 idetape_update_buffers(drive, pc); 425 } 426 427 /* 428 * If error was the result of a zero-length read or write command, 429 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 430 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 431 */ 432 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 433 /* length == 0 */ 434 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 435 if (tape->sense_key == 5) { 436 /* don't report an error, everything's ok */ 437 pc->error = 0; 438 /* don't retry read/write */ 439 pc->flags |= PC_FLAG_ABORT; 440 } 441 } 442 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 443 pc->error = IDETAPE_ERROR_FILEMARK; 444 pc->flags |= PC_FLAG_ABORT; 445 } 446 if (pc->c[0] == WRITE_6) { 447 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 448 && tape->asc == 0x0 && tape->ascq == 0x2)) { 449 pc->error = IDETAPE_ERROR_EOD; 450 pc->flags |= PC_FLAG_ABORT; 451 } 452 } 453 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 454 if (tape->sense_key == 8) { 455 pc->error = IDETAPE_ERROR_EOD; 456 pc->flags |= PC_FLAG_ABORT; 457 } 458 if (!(pc->flags & PC_FLAG_ABORT) && 459 pc->xferred) 460 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 461 } 462} 463 464/* Free data buffers completely. */ 465static void ide_tape_kfree_buffer(idetape_tape_t *tape) 466{ 467 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 468 469 while (bh) { 470 u32 size = bh->b_size; 471 472 while (size) { 473 unsigned int order = fls(size >> PAGE_SHIFT)-1; 474 475 if (bh->b_data) 476 free_pages((unsigned long)bh->b_data, order); 477 478 size &= (order-1); 479 bh->b_data += (1 << order) * PAGE_SIZE; 480 } 481 prev_bh = bh; 482 bh = bh->b_reqnext; 483 kfree(prev_bh); 484 } 485} 486 487static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 488{ 489 struct request *rq = HWGROUP(drive)->rq; 490 idetape_tape_t *tape = drive->driver_data; 491 unsigned long flags; 492 int error; 493 494 debug_log(DBG_PROCS, "Enter %s\n", __func__); 495 496 switch (uptodate) { 497 case 0: error = IDETAPE_ERROR_GENERAL; break; 498 case 1: error = 0; break; 499 default: error = uptodate; 500 } 501 rq->errors = error; 502 if (error) 503 tape->failed_pc = NULL; 504 505 if (!blk_special_request(rq)) { 506 ide_end_request(drive, uptodate, nr_sects); 507 return 0; 508 } 509 510 spin_lock_irqsave(&tape->lock, flags); 511 512 ide_end_drive_cmd(drive, 0, 0); 513 514 spin_unlock_irqrestore(&tape->lock, flags); 515 return 0; 516} 517 518static void ide_tape_handle_dsc(ide_drive_t *); 519 520static void ide_tape_callback(ide_drive_t *drive, int dsc) 521{ 522 idetape_tape_t *tape = drive->driver_data; 523 struct ide_atapi_pc *pc = drive->pc; 524 int uptodate = pc->error ? 0 : 1; 525 526 debug_log(DBG_PROCS, "Enter %s\n", __func__); 527 528 if (dsc) 529 ide_tape_handle_dsc(drive); 530 531 if (tape->failed_pc == pc) 532 tape->failed_pc = NULL; 533 534 if (pc->c[0] == REQUEST_SENSE) { 535 if (uptodate) 536 idetape_analyze_error(drive, pc->buf); 537 else 538 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 539 "itself - Aborting request!\n"); 540 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 541 struct request *rq = drive->hwif->hwgroup->rq; 542 int blocks = pc->xferred / tape->blk_size; 543 544 tape->avg_size += blocks * tape->blk_size; 545 546 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 547 tape->avg_speed = tape->avg_size * HZ / 548 (jiffies - tape->avg_time) / 1024; 549 tape->avg_size = 0; 550 tape->avg_time = jiffies; 551 } 552 553 tape->first_frame += blocks; 554 rq->current_nr_sectors -= blocks; 555 556 if (pc->error) 557 uptodate = pc->error; 558 } else if (pc->c[0] == READ_POSITION && uptodate) { 559 u8 *readpos = pc->buf; 560 561 debug_log(DBG_SENSE, "BOP - %s\n", 562 (readpos[0] & 0x80) ? "Yes" : "No"); 563 debug_log(DBG_SENSE, "EOP - %s\n", 564 (readpos[0] & 0x40) ? "Yes" : "No"); 565 566 if (readpos[0] & 0x4) { 567 printk(KERN_INFO "ide-tape: Block location is unknown" 568 "to the tape\n"); 569 clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 570 uptodate = 0; 571 } else { 572 debug_log(DBG_SENSE, "Block Location - %u\n", 573 be32_to_cpup((__be32 *)&readpos[4])); 574 575 tape->partition = readpos[1]; 576 tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]); 577 set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 578 } 579 } 580 581 idetape_end_request(drive, uptodate, 0); 582} 583 584static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc) 585{ 586 ide_init_pc(pc); 587 pc->c[0] = REQUEST_SENSE; 588 pc->c[4] = 20; 589 pc->req_xfer = 20; 590} 591 592/* 593 * idetape_retry_pc is called when an error was detected during the 594 * last packet command. We queue a request sense packet command in 595 * the head of the request list. 596 */ 597static void idetape_retry_pc(ide_drive_t *drive) 598{ 599 struct ide_tape_obj *tape = drive->driver_data; 600 struct request *rq = &drive->request_sense_rq; 601 struct ide_atapi_pc *pc = &drive->request_sense_pc; 602 603 (void)ide_read_error(drive); 604 idetape_create_request_sense_cmd(pc); 605 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 606 ide_queue_pc_head(drive, tape->disk, pc, rq); 607} 608 609/* 610 * Postpone the current request so that ide.c will be able to service requests 611 * from another device on the same hwgroup while we are polling for DSC. 612 */ 613static void idetape_postpone_request(ide_drive_t *drive) 614{ 615 idetape_tape_t *tape = drive->driver_data; 616 617 debug_log(DBG_PROCS, "Enter %s\n", __func__); 618 619 tape->postponed_rq = HWGROUP(drive)->rq; 620 ide_stall_queue(drive, tape->dsc_poll_freq); 621} 622 623static void ide_tape_handle_dsc(ide_drive_t *drive) 624{ 625 idetape_tape_t *tape = drive->driver_data; 626 627 /* Media access command */ 628 tape->dsc_polling_start = jiffies; 629 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 630 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 631 /* Allow ide.c to handle other requests */ 632 idetape_postpone_request(drive); 633} 634 635static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 636 unsigned int bcount, int write) 637{ 638 if (write) 639 idetape_output_buffers(drive, pc, bcount); 640 else 641 idetape_input_buffers(drive, pc, bcount); 642 643 return bcount; 644} 645 646/* 647 * This is the usual interrupt handler which will be called during a packet 648 * command. We will transfer some of the data (as requested by the drive) and 649 * will re-point interrupt handler to us. When data transfer is finished, we 650 * will act according to the algorithm described before 651 * idetape_issue_pc. 652 */ 653static ide_startstop_t idetape_pc_intr(ide_drive_t *drive) 654{ 655 return ide_pc_intr(drive, idetape_pc_intr, idetape_update_buffers, 656 idetape_retry_pc, ide_tape_io_buffers); 657} 658 659/* 660 * Packet Command Interface 661 * 662 * The current Packet Command is available in drive->pc, and will not change 663 * until we finish handling it. Each packet command is associated with a 664 * callback function that will be called when the command is finished. 665 * 666 * The handling will be done in three stages: 667 * 668 * 1. idetape_issue_pc will send the packet command to the drive, and will set 669 * the interrupt handler to idetape_pc_intr. 670 * 671 * 2. On each interrupt, idetape_pc_intr will be called. This step will be 672 * repeated until the device signals us that no more interrupts will be issued. 673 * 674 * 3. ATAPI Tape media access commands have immediate status with a delayed 675 * process. In case of a successful initiation of a media access packet command, 676 * the DSC bit will be set when the actual execution of the command is finished. 677 * Since the tape drive will not issue an interrupt, we have to poll for this 678 * event. In this case, we define the request as "low priority request" by 679 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 680 * exit the driver. 681 * 682 * ide.c will then give higher priority to requests which originate from the 683 * other device, until will change rq_status to RQ_ACTIVE. 684 * 685 * 4. When the packet command is finished, it will be checked for errors. 686 * 687 * 5. In case an error was found, we queue a request sense packet command in 688 * front of the request queue and retry the operation up to 689 * IDETAPE_MAX_PC_RETRIES times. 690 * 691 * 6. In case no error was found, or we decided to give up and not to retry 692 * again, the callback function will be called and then we will handle the next 693 * request. 694 */ 695static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 696{ 697 return ide_transfer_pc(drive, idetape_pc_intr, WAIT_TAPE_CMD, NULL); 698} 699 700static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 701 struct ide_atapi_pc *pc) 702{ 703 idetape_tape_t *tape = drive->driver_data; 704 705 if (drive->pc->c[0] == REQUEST_SENSE && 706 pc->c[0] == REQUEST_SENSE) { 707 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 708 "Two request sense in serial were issued\n"); 709 } 710 711 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 712 tape->failed_pc = pc; 713 714 /* Set the current packet command */ 715 drive->pc = pc; 716 717 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 718 (pc->flags & PC_FLAG_ABORT)) { 719 /* 720 * We will "abort" retrying a packet command in case legitimate 721 * error code was received (crossing a filemark, or end of the 722 * media, for example). 723 */ 724 if (!(pc->flags & PC_FLAG_ABORT)) { 725 if (!(pc->c[0] == TEST_UNIT_READY && 726 tape->sense_key == 2 && tape->asc == 4 && 727 (tape->ascq == 1 || tape->ascq == 8))) { 728 printk(KERN_ERR "ide-tape: %s: I/O error, " 729 "pc = %2x, key = %2x, " 730 "asc = %2x, ascq = %2x\n", 731 tape->name, pc->c[0], 732 tape->sense_key, tape->asc, 733 tape->ascq); 734 } 735 /* Giving up */ 736 pc->error = IDETAPE_ERROR_GENERAL; 737 } 738 tape->failed_pc = NULL; 739 drive->pc_callback(drive, 0); 740 return ide_stopped; 741 } 742 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 743 744 pc->retries++; 745 746 return ide_issue_pc(drive, idetape_transfer_pc, WAIT_TAPE_CMD, NULL); 747} 748 749/* A mode sense command is used to "sense" tape parameters. */ 750static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 751{ 752 ide_init_pc(pc); 753 pc->c[0] = MODE_SENSE; 754 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 755 /* DBD = 1 - Don't return block descriptors */ 756 pc->c[1] = 8; 757 pc->c[2] = page_code; 758 /* 759 * Changed pc->c[3] to 0 (255 will at best return unused info). 760 * 761 * For SCSI this byte is defined as subpage instead of high byte 762 * of length and some IDE drives seem to interpret it this way 763 * and return an error when 255 is used. 764 */ 765 pc->c[3] = 0; 766 /* We will just discard data in that case */ 767 pc->c[4] = 255; 768 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 769 pc->req_xfer = 12; 770 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 771 pc->req_xfer = 24; 772 else 773 pc->req_xfer = 50; 774} 775 776static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 777{ 778 ide_hwif_t *hwif = drive->hwif; 779 idetape_tape_t *tape = drive->driver_data; 780 struct ide_atapi_pc *pc = drive->pc; 781 u8 stat; 782 783 stat = hwif->tp_ops->read_status(hwif); 784 785 if (stat & ATA_DSC) { 786 if (stat & ATA_ERR) { 787 /* Error detected */ 788 if (pc->c[0] != TEST_UNIT_READY) 789 printk(KERN_ERR "ide-tape: %s: I/O error, ", 790 tape->name); 791 /* Retry operation */ 792 idetape_retry_pc(drive); 793 return ide_stopped; 794 } 795 pc->error = 0; 796 } else { 797 pc->error = IDETAPE_ERROR_GENERAL; 798 tape->failed_pc = NULL; 799 } 800 drive->pc_callback(drive, 0); 801 return ide_stopped; 802} 803 804static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 805 struct ide_atapi_pc *pc, struct request *rq, 806 u8 opcode) 807{ 808 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 809 unsigned int length = rq->current_nr_sectors; 810 811 ide_init_pc(pc); 812 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 813 pc->c[1] = 1; 814 pc->bh = bh; 815 pc->buf = NULL; 816 pc->buf_size = length * tape->blk_size; 817 pc->req_xfer = pc->buf_size; 818 if (pc->req_xfer == tape->buffer_size) 819 pc->flags |= PC_FLAG_DMA_OK; 820 821 if (opcode == READ_6) { 822 pc->c[0] = READ_6; 823 atomic_set(&bh->b_count, 0); 824 } else if (opcode == WRITE_6) { 825 pc->c[0] = WRITE_6; 826 pc->flags |= PC_FLAG_WRITING; 827 pc->b_data = bh->b_data; 828 pc->b_count = atomic_read(&bh->b_count); 829 } 830 831 memcpy(rq->cmd, pc->c, 12); 832} 833 834static ide_startstop_t idetape_do_request(ide_drive_t *drive, 835 struct request *rq, sector_t block) 836{ 837 ide_hwif_t *hwif = drive->hwif; 838 idetape_tape_t *tape = drive->driver_data; 839 struct ide_atapi_pc *pc = NULL; 840 struct request *postponed_rq = tape->postponed_rq; 841 u8 stat; 842 843 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 844 " current_nr_sectors: %u\n", 845 (unsigned long long)rq->sector, rq->nr_sectors, 846 rq->current_nr_sectors); 847 848 if (!blk_special_request(rq)) { 849 /* We do not support buffer cache originated requests. */ 850 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 851 "request queue (%d)\n", drive->name, rq->cmd_type); 852 ide_end_request(drive, 0, 0); 853 return ide_stopped; 854 } 855 856 /* Retry a failed packet command */ 857 if (tape->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { 858 pc = tape->failed_pc; 859 goto out; 860 } 861 862 if (postponed_rq != NULL) 863 if (rq != postponed_rq) { 864 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 865 "Two DSC requests were queued\n"); 866 idetape_end_request(drive, 0, 0); 867 return ide_stopped; 868 } 869 870 tape->postponed_rq = NULL; 871 872 /* 873 * If the tape is still busy, postpone our request and service 874 * the other device meanwhile. 875 */ 876 stat = hwif->tp_ops->read_status(hwif); 877 878 if (!drive->dsc_overlap && !(rq->cmd[13] & REQ_IDETAPE_PC2)) 879 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 880 881 if (drive->post_reset == 1) { 882 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 883 drive->post_reset = 0; 884 } 885 886 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 887 (stat & ATA_DSC) == 0) { 888 if (postponed_rq == NULL) { 889 tape->dsc_polling_start = jiffies; 890 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 891 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 892 } else if (time_after(jiffies, tape->dsc_timeout)) { 893 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 894 tape->name); 895 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 896 idetape_media_access_finished(drive); 897 return ide_stopped; 898 } else { 899 return ide_do_reset(drive); 900 } 901 } else if (time_after(jiffies, 902 tape->dsc_polling_start + 903 IDETAPE_DSC_MA_THRESHOLD)) 904 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 905 idetape_postpone_request(drive); 906 return ide_stopped; 907 } 908 if (rq->cmd[13] & REQ_IDETAPE_READ) { 909 pc = &tape->queued_pc; 910 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 911 goto out; 912 } 913 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 914 pc = &tape->queued_pc; 915 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 916 goto out; 917 } 918 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 919 pc = (struct ide_atapi_pc *) rq->buffer; 920 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 921 rq->cmd[13] |= REQ_IDETAPE_PC2; 922 goto out; 923 } 924 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 925 idetape_media_access_finished(drive); 926 return ide_stopped; 927 } 928 BUG(); 929 930out: 931 return idetape_issue_pc(drive, pc); 932} 933 934/* 935 * The function below uses __get_free_pages to allocate a data buffer of size 936 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 937 * much as possible. 938 * 939 * It returns a pointer to the newly allocated buffer, or NULL in case of 940 * failure. 941 */ 942static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 943 int full, int clear) 944{ 945 struct idetape_bh *prev_bh, *bh, *merge_bh; 946 int pages = tape->pages_per_buffer; 947 unsigned int order, b_allocd; 948 char *b_data = NULL; 949 950 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 951 bh = merge_bh; 952 if (bh == NULL) 953 goto abort; 954 955 order = fls(pages) - 1; 956 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 957 if (!bh->b_data) 958 goto abort; 959 b_allocd = (1 << order) * PAGE_SIZE; 960 pages &= (order-1); 961 962 if (clear) 963 memset(bh->b_data, 0, b_allocd); 964 bh->b_reqnext = NULL; 965 bh->b_size = b_allocd; 966 atomic_set(&bh->b_count, full ? bh->b_size : 0); 967 968 while (pages) { 969 order = fls(pages) - 1; 970 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 971 if (!b_data) 972 goto abort; 973 b_allocd = (1 << order) * PAGE_SIZE; 974 975 if (clear) 976 memset(b_data, 0, b_allocd); 977 978 /* newly allocated page frames below buffer header or ...*/ 979 if (bh->b_data == b_data + b_allocd) { 980 bh->b_size += b_allocd; 981 bh->b_data -= b_allocd; 982 if (full) 983 atomic_add(b_allocd, &bh->b_count); 984 continue; 985 } 986 /* they are above the header */ 987 if (b_data == bh->b_data + bh->b_size) { 988 bh->b_size += b_allocd; 989 if (full) 990 atomic_add(b_allocd, &bh->b_count); 991 continue; 992 } 993 prev_bh = bh; 994 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 995 if (!bh) { 996 free_pages((unsigned long) b_data, order); 997 goto abort; 998 } 999 bh->b_reqnext = NULL; 1000 bh->b_data = b_data; 1001 bh->b_size = b_allocd; 1002 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1003 prev_bh->b_reqnext = bh; 1004 1005 pages &= (order-1); 1006 } 1007 1008 bh->b_size -= tape->excess_bh_size; 1009 if (full) 1010 atomic_sub(tape->excess_bh_size, &bh->b_count); 1011 return merge_bh; 1012abort: 1013 ide_tape_kfree_buffer(tape); 1014 return NULL; 1015} 1016 1017static int idetape_copy_stage_from_user(idetape_tape_t *tape, 1018 const char __user *buf, int n) 1019{ 1020 struct idetape_bh *bh = tape->bh; 1021 int count; 1022 int ret = 0; 1023 1024 while (n) { 1025 if (bh == NULL) { 1026 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1027 __func__); 1028 return 1; 1029 } 1030 count = min((unsigned int) 1031 (bh->b_size - atomic_read(&bh->b_count)), 1032 (unsigned int)n); 1033 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 1034 count)) 1035 ret = 1; 1036 n -= count; 1037 atomic_add(count, &bh->b_count); 1038 buf += count; 1039 if (atomic_read(&bh->b_count) == bh->b_size) { 1040 bh = bh->b_reqnext; 1041 if (bh) 1042 atomic_set(&bh->b_count, 0); 1043 } 1044 } 1045 tape->bh = bh; 1046 return ret; 1047} 1048 1049static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1050 int n) 1051{ 1052 struct idetape_bh *bh = tape->bh; 1053 int count; 1054 int ret = 0; 1055 1056 while (n) { 1057 if (bh == NULL) { 1058 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1059 __func__); 1060 return 1; 1061 } 1062 count = min(tape->b_count, n); 1063 if (copy_to_user(buf, tape->b_data, count)) 1064 ret = 1; 1065 n -= count; 1066 tape->b_data += count; 1067 tape->b_count -= count; 1068 buf += count; 1069 if (!tape->b_count) { 1070 bh = bh->b_reqnext; 1071 tape->bh = bh; 1072 if (bh) { 1073 tape->b_data = bh->b_data; 1074 tape->b_count = atomic_read(&bh->b_count); 1075 } 1076 } 1077 } 1078 return ret; 1079} 1080 1081static void idetape_init_merge_buffer(idetape_tape_t *tape) 1082{ 1083 struct idetape_bh *bh = tape->merge_bh; 1084 tape->bh = tape->merge_bh; 1085 1086 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1087 atomic_set(&bh->b_count, 0); 1088 else { 1089 tape->b_data = bh->b_data; 1090 tape->b_count = atomic_read(&bh->b_count); 1091 } 1092} 1093 1094/* 1095 * Write a filemark if write_filemark=1. Flush the device buffers without 1096 * writing a filemark otherwise. 1097 */ 1098static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1099 struct ide_atapi_pc *pc, int write_filemark) 1100{ 1101 ide_init_pc(pc); 1102 pc->c[0] = WRITE_FILEMARKS; 1103 pc->c[4] = write_filemark; 1104 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1105} 1106 1107static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1108{ 1109 idetape_tape_t *tape = drive->driver_data; 1110 struct gendisk *disk = tape->disk; 1111 int load_attempted = 0; 1112 1113 /* Wait for the tape to become ready */ 1114 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1115 timeout += jiffies; 1116 while (time_before(jiffies, timeout)) { 1117 if (ide_do_test_unit_ready(drive, disk) == 0) 1118 return 0; 1119 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1120 || (tape->asc == 0x3A)) { 1121 /* no media */ 1122 if (load_attempted) 1123 return -ENOMEDIUM; 1124 ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1125 load_attempted = 1; 1126 /* not about to be ready */ 1127 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1128 (tape->ascq == 1 || tape->ascq == 8))) 1129 return -EIO; 1130 msleep(100); 1131 } 1132 return -EIO; 1133} 1134 1135static int idetape_flush_tape_buffers(ide_drive_t *drive) 1136{ 1137 struct ide_tape_obj *tape = drive->driver_data; 1138 struct ide_atapi_pc pc; 1139 int rc; 1140 1141 idetape_create_write_filemark_cmd(drive, &pc, 0); 1142 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1143 if (rc) 1144 return rc; 1145 idetape_wait_ready(drive, 60 * 5 * HZ); 1146 return 0; 1147} 1148 1149static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1150{ 1151 ide_init_pc(pc); 1152 pc->c[0] = READ_POSITION; 1153 pc->req_xfer = 20; 1154} 1155 1156static int idetape_read_position(ide_drive_t *drive) 1157{ 1158 idetape_tape_t *tape = drive->driver_data; 1159 struct ide_atapi_pc pc; 1160 int position; 1161 1162 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1163 1164 idetape_create_read_position_cmd(&pc); 1165 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1166 return -1; 1167 position = tape->first_frame; 1168 return position; 1169} 1170 1171static void idetape_create_locate_cmd(ide_drive_t *drive, 1172 struct ide_atapi_pc *pc, 1173 unsigned int block, u8 partition, int skip) 1174{ 1175 ide_init_pc(pc); 1176 pc->c[0] = POSITION_TO_ELEMENT; 1177 pc->c[1] = 2; 1178 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1179 pc->c[8] = partition; 1180 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1181} 1182 1183static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1184{ 1185 idetape_tape_t *tape = drive->driver_data; 1186 1187 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1188 return; 1189 1190 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1191 tape->merge_bh_size = 0; 1192 if (tape->merge_bh != NULL) { 1193 ide_tape_kfree_buffer(tape); 1194 tape->merge_bh = NULL; 1195 } 1196 1197 tape->chrdev_dir = IDETAPE_DIR_NONE; 1198} 1199 1200/* 1201 * Position the tape to the requested block using the LOCATE packet command. 1202 * A READ POSITION command is then issued to check where we are positioned. Like 1203 * all higher level operations, we queue the commands at the tail of the request 1204 * queue and wait for their completion. 1205 */ 1206static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1207 u8 partition, int skip) 1208{ 1209 idetape_tape_t *tape = drive->driver_data; 1210 struct gendisk *disk = tape->disk; 1211 int retval; 1212 struct ide_atapi_pc pc; 1213 1214 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1215 __ide_tape_discard_merge_buffer(drive); 1216 idetape_wait_ready(drive, 60 * 5 * HZ); 1217 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1218 retval = ide_queue_pc_tail(drive, disk, &pc); 1219 if (retval) 1220 return (retval); 1221 1222 idetape_create_read_position_cmd(&pc); 1223 return ide_queue_pc_tail(drive, disk, &pc); 1224} 1225 1226static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1227 int restore_position) 1228{ 1229 idetape_tape_t *tape = drive->driver_data; 1230 int seek, position; 1231 1232 __ide_tape_discard_merge_buffer(drive); 1233 if (restore_position) { 1234 position = idetape_read_position(drive); 1235 seek = position > 0 ? position : 0; 1236 if (idetape_position_tape(drive, seek, 0, 0)) { 1237 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1238 " %s\n", tape->name, __func__); 1239 return; 1240 } 1241 } 1242} 1243 1244/* 1245 * Generate a read/write request for the block device interface and wait for it 1246 * to be serviced. 1247 */ 1248static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1249 struct idetape_bh *bh) 1250{ 1251 idetape_tape_t *tape = drive->driver_data; 1252 struct request *rq; 1253 int ret, errors; 1254 1255 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1256 1257 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1258 rq->cmd_type = REQ_TYPE_SPECIAL; 1259 rq->cmd[13] = cmd; 1260 rq->rq_disk = tape->disk; 1261 rq->special = (void *)bh; 1262 rq->sector = tape->first_frame; 1263 rq->nr_sectors = blocks; 1264 rq->current_nr_sectors = blocks; 1265 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1266 1267 errors = rq->errors; 1268 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1269 blk_put_request(rq); 1270 1271 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1272 return 0; 1273 1274 if (tape->merge_bh) 1275 idetape_init_merge_buffer(tape); 1276 if (errors == IDETAPE_ERROR_GENERAL) 1277 return -EIO; 1278 return ret; 1279} 1280 1281static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1282{ 1283 ide_init_pc(pc); 1284 pc->c[0] = INQUIRY; 1285 pc->c[4] = 254; 1286 pc->req_xfer = 254; 1287} 1288 1289static void idetape_create_rewind_cmd(ide_drive_t *drive, 1290 struct ide_atapi_pc *pc) 1291{ 1292 ide_init_pc(pc); 1293 pc->c[0] = REZERO_UNIT; 1294 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1295} 1296 1297static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1298{ 1299 ide_init_pc(pc); 1300 pc->c[0] = ERASE; 1301 pc->c[1] = 1; 1302 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1303} 1304 1305static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1306{ 1307 ide_init_pc(pc); 1308 pc->c[0] = SPACE; 1309 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1310 pc->c[1] = cmd; 1311 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1312} 1313 1314/* Queue up a character device originated write request. */ 1315static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1316{ 1317 idetape_tape_t *tape = drive->driver_data; 1318 1319 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1320 1321 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1322 blocks, tape->merge_bh); 1323} 1324 1325static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1326{ 1327 idetape_tape_t *tape = drive->driver_data; 1328 int blocks, min; 1329 struct idetape_bh *bh; 1330 1331 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1332 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1333 " but we are not writing.\n"); 1334 return; 1335 } 1336 if (tape->merge_bh_size > tape->buffer_size) { 1337 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1338 tape->merge_bh_size = tape->buffer_size; 1339 } 1340 if (tape->merge_bh_size) { 1341 blocks = tape->merge_bh_size / tape->blk_size; 1342 if (tape->merge_bh_size % tape->blk_size) { 1343 unsigned int i; 1344 1345 blocks++; 1346 i = tape->blk_size - tape->merge_bh_size % 1347 tape->blk_size; 1348 bh = tape->bh->b_reqnext; 1349 while (bh) { 1350 atomic_set(&bh->b_count, 0); 1351 bh = bh->b_reqnext; 1352 } 1353 bh = tape->bh; 1354 while (i) { 1355 if (bh == NULL) { 1356 printk(KERN_INFO "ide-tape: bug," 1357 " bh NULL\n"); 1358 break; 1359 } 1360 min = min(i, (unsigned int)(bh->b_size - 1361 atomic_read(&bh->b_count))); 1362 memset(bh->b_data + atomic_read(&bh->b_count), 1363 0, min); 1364 atomic_add(min, &bh->b_count); 1365 i -= min; 1366 bh = bh->b_reqnext; 1367 } 1368 } 1369 (void) idetape_add_chrdev_write_request(drive, blocks); 1370 tape->merge_bh_size = 0; 1371 } 1372 if (tape->merge_bh != NULL) { 1373 ide_tape_kfree_buffer(tape); 1374 tape->merge_bh = NULL; 1375 } 1376 tape->chrdev_dir = IDETAPE_DIR_NONE; 1377} 1378 1379static int idetape_init_read(ide_drive_t *drive) 1380{ 1381 idetape_tape_t *tape = drive->driver_data; 1382 int bytes_read; 1383 1384 /* Initialize read operation */ 1385 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1386 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1387 ide_tape_flush_merge_buffer(drive); 1388 idetape_flush_tape_buffers(drive); 1389 } 1390 if (tape->merge_bh || tape->merge_bh_size) { 1391 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1392 " 0 now\n"); 1393 tape->merge_bh_size = 0; 1394 } 1395 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1396 if (!tape->merge_bh) 1397 return -ENOMEM; 1398 tape->chrdev_dir = IDETAPE_DIR_READ; 1399 1400 /* 1401 * Issue a read 0 command to ensure that DSC handshake is 1402 * switched from completion mode to buffer available mode. 1403 * No point in issuing this if DSC overlap isn't supported, some 1404 * drives (Seagate STT3401A) will return an error. 1405 */ 1406 if (drive->dsc_overlap) { 1407 bytes_read = idetape_queue_rw_tail(drive, 1408 REQ_IDETAPE_READ, 0, 1409 tape->merge_bh); 1410 if (bytes_read < 0) { 1411 ide_tape_kfree_buffer(tape); 1412 tape->merge_bh = NULL; 1413 tape->chrdev_dir = IDETAPE_DIR_NONE; 1414 return bytes_read; 1415 } 1416 } 1417 } 1418 1419 return 0; 1420} 1421 1422/* called from idetape_chrdev_read() to service a chrdev read request. */ 1423static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1424{ 1425 idetape_tape_t *tape = drive->driver_data; 1426 1427 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1428 1429 /* If we are at a filemark, return a read length of 0 */ 1430 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1431 return 0; 1432 1433 idetape_init_read(drive); 1434 1435 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1436 tape->merge_bh); 1437} 1438 1439static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1440{ 1441 idetape_tape_t *tape = drive->driver_data; 1442 struct idetape_bh *bh; 1443 int blocks; 1444 1445 while (bcount) { 1446 unsigned int count; 1447 1448 bh = tape->merge_bh; 1449 count = min(tape->buffer_size, bcount); 1450 bcount -= count; 1451 blocks = count / tape->blk_size; 1452 while (count) { 1453 atomic_set(&bh->b_count, 1454 min(count, (unsigned int)bh->b_size)); 1455 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1456 count -= atomic_read(&bh->b_count); 1457 bh = bh->b_reqnext; 1458 } 1459 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1460 tape->merge_bh); 1461 } 1462} 1463 1464/* 1465 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1466 * currently support only one partition. 1467 */ 1468static int idetape_rewind_tape(ide_drive_t *drive) 1469{ 1470 struct ide_tape_obj *tape = drive->driver_data; 1471 struct gendisk *disk = tape->disk; 1472 int retval; 1473 struct ide_atapi_pc pc; 1474 1475 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1476 1477 idetape_create_rewind_cmd(drive, &pc); 1478 retval = ide_queue_pc_tail(drive, disk, &pc); 1479 if (retval) 1480 return retval; 1481 1482 idetape_create_read_position_cmd(&pc); 1483 retval = ide_queue_pc_tail(drive, disk, &pc); 1484 if (retval) 1485 return retval; 1486 return 0; 1487} 1488 1489/* mtio.h compatible commands should be issued to the chrdev interface. */ 1490static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1491 unsigned long arg) 1492{ 1493 idetape_tape_t *tape = drive->driver_data; 1494 void __user *argp = (void __user *)arg; 1495 1496 struct idetape_config { 1497 int dsc_rw_frequency; 1498 int dsc_media_access_frequency; 1499 int nr_stages; 1500 } config; 1501 1502 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1503 1504 switch (cmd) { 1505 case 0x0340: 1506 if (copy_from_user(&config, argp, sizeof(config))) 1507 return -EFAULT; 1508 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1509 break; 1510 case 0x0350: 1511 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1512 config.nr_stages = 1; 1513 if (copy_to_user(argp, &config, sizeof(config))) 1514 return -EFAULT; 1515 break; 1516 default: 1517 return -EIO; 1518 } 1519 return 0; 1520} 1521 1522static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1523 int mt_count) 1524{ 1525 idetape_tape_t *tape = drive->driver_data; 1526 struct gendisk *disk = tape->disk; 1527 struct ide_atapi_pc pc; 1528 int retval, count = 0; 1529 int sprev = !!(tape->caps[4] & 0x20); 1530 1531 if (mt_count == 0) 1532 return 0; 1533 if (MTBSF == mt_op || MTBSFM == mt_op) { 1534 if (!sprev) 1535 return -EIO; 1536 mt_count = -mt_count; 1537 } 1538 1539 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1540 tape->merge_bh_size = 0; 1541 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1542 ++count; 1543 ide_tape_discard_merge_buffer(drive, 0); 1544 } 1545 1546 switch (mt_op) { 1547 case MTFSF: 1548 case MTBSF: 1549 idetape_create_space_cmd(&pc, mt_count - count, 1550 IDETAPE_SPACE_OVER_FILEMARK); 1551 return ide_queue_pc_tail(drive, disk, &pc); 1552 case MTFSFM: 1553 case MTBSFM: 1554 if (!sprev) 1555 return -EIO; 1556 retval = idetape_space_over_filemarks(drive, MTFSF, 1557 mt_count - count); 1558 if (retval) 1559 return retval; 1560 count = (MTBSFM == mt_op ? 1 : -1); 1561 return idetape_space_over_filemarks(drive, MTFSF, count); 1562 default: 1563 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1564 mt_op); 1565 return -EIO; 1566 } 1567} 1568 1569/* 1570 * Our character device read / write functions. 1571 * 1572 * The tape is optimized to maximize throughput when it is transferring an 1573 * integral number of the "continuous transfer limit", which is a parameter of 1574 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1575 * 1576 * As of version 1.3 of the driver, the character device provides an abstract 1577 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1578 * same backup/restore procedure is supported. The driver will internally 1579 * convert the requests to the recommended transfer unit, so that an unmatch 1580 * between the user's block size to the recommended size will only result in a 1581 * (slightly) increased driver overhead, but will no longer hit performance. 1582 * This is not applicable to Onstream. 1583 */ 1584static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1585 size_t count, loff_t *ppos) 1586{ 1587 struct ide_tape_obj *tape = ide_tape_f(file); 1588 ide_drive_t *drive = tape->drive; 1589 ssize_t bytes_read, temp, actually_read = 0, rc; 1590 ssize_t ret = 0; 1591 u16 ctl = *(u16 *)&tape->caps[12]; 1592 1593 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1594 1595 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1596 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1597 if (count > tape->blk_size && 1598 (count % tape->blk_size) == 0) 1599 tape->user_bs_factor = count / tape->blk_size; 1600 } 1601 rc = idetape_init_read(drive); 1602 if (rc < 0) 1603 return rc; 1604 if (count == 0) 1605 return (0); 1606 if (tape->merge_bh_size) { 1607 actually_read = min((unsigned int)(tape->merge_bh_size), 1608 (unsigned int)count); 1609 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1610 ret = -EFAULT; 1611 buf += actually_read; 1612 tape->merge_bh_size -= actually_read; 1613 count -= actually_read; 1614 } 1615 while (count >= tape->buffer_size) { 1616 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1617 if (bytes_read <= 0) 1618 goto finish; 1619 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1620 ret = -EFAULT; 1621 buf += bytes_read; 1622 count -= bytes_read; 1623 actually_read += bytes_read; 1624 } 1625 if (count) { 1626 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1627 if (bytes_read <= 0) 1628 goto finish; 1629 temp = min((unsigned long)count, (unsigned long)bytes_read); 1630 if (idetape_copy_stage_to_user(tape, buf, temp)) 1631 ret = -EFAULT; 1632 actually_read += temp; 1633 tape->merge_bh_size = bytes_read-temp; 1634 } 1635finish: 1636 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1637 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1638 1639 idetape_space_over_filemarks(drive, MTFSF, 1); 1640 return 0; 1641 } 1642 1643 return ret ? ret : actually_read; 1644} 1645 1646static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1647 size_t count, loff_t *ppos) 1648{ 1649 struct ide_tape_obj *tape = ide_tape_f(file); 1650 ide_drive_t *drive = tape->drive; 1651 ssize_t actually_written = 0; 1652 ssize_t ret = 0; 1653 u16 ctl = *(u16 *)&tape->caps[12]; 1654 1655 /* The drive is write protected. */ 1656 if (tape->write_prot) 1657 return -EACCES; 1658 1659 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1660 1661 /* Initialize write operation */ 1662 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1663 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1664 ide_tape_discard_merge_buffer(drive, 1); 1665 if (tape->merge_bh || tape->merge_bh_size) { 1666 printk(KERN_ERR "ide-tape: merge_bh_size " 1667 "should be 0 now\n"); 1668 tape->merge_bh_size = 0; 1669 } 1670 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1671 if (!tape->merge_bh) 1672 return -ENOMEM; 1673 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1674 idetape_init_merge_buffer(tape); 1675 1676 /* 1677 * Issue a write 0 command to ensure that DSC handshake is 1678 * switched from completion mode to buffer available mode. No 1679 * point in issuing this if DSC overlap isn't supported, some 1680 * drives (Seagate STT3401A) will return an error. 1681 */ 1682 if (drive->dsc_overlap) { 1683 ssize_t retval = idetape_queue_rw_tail(drive, 1684 REQ_IDETAPE_WRITE, 0, 1685 tape->merge_bh); 1686 if (retval < 0) { 1687 ide_tape_kfree_buffer(tape); 1688 tape->merge_bh = NULL; 1689 tape->chrdev_dir = IDETAPE_DIR_NONE; 1690 return retval; 1691 } 1692 } 1693 } 1694 if (count == 0) 1695 return (0); 1696 if (tape->merge_bh_size) { 1697 if (tape->merge_bh_size >= tape->buffer_size) { 1698 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1699 tape->merge_bh_size = 0; 1700 } 1701 actually_written = min((unsigned int) 1702 (tape->buffer_size - tape->merge_bh_size), 1703 (unsigned int)count); 1704 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1705 ret = -EFAULT; 1706 buf += actually_written; 1707 tape->merge_bh_size += actually_written; 1708 count -= actually_written; 1709 1710 if (tape->merge_bh_size == tape->buffer_size) { 1711 ssize_t retval; 1712 tape->merge_bh_size = 0; 1713 retval = idetape_add_chrdev_write_request(drive, ctl); 1714 if (retval <= 0) 1715 return (retval); 1716 } 1717 } 1718 while (count >= tape->buffer_size) { 1719 ssize_t retval; 1720 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1721 ret = -EFAULT; 1722 buf += tape->buffer_size; 1723 count -= tape->buffer_size; 1724 retval = idetape_add_chrdev_write_request(drive, ctl); 1725 actually_written += tape->buffer_size; 1726 if (retval <= 0) 1727 return (retval); 1728 } 1729 if (count) { 1730 actually_written += count; 1731 if (idetape_copy_stage_from_user(tape, buf, count)) 1732 ret = -EFAULT; 1733 tape->merge_bh_size += count; 1734 } 1735 return ret ? ret : actually_written; 1736} 1737 1738static int idetape_write_filemark(ide_drive_t *drive) 1739{ 1740 struct ide_tape_obj *tape = drive->driver_data; 1741 struct ide_atapi_pc pc; 1742 1743 /* Write a filemark */ 1744 idetape_create_write_filemark_cmd(drive, &pc, 1); 1745 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1746 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1747 return -EIO; 1748 } 1749 return 0; 1750} 1751 1752/* 1753 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1754 * requested. 1755 * 1756 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1757 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1758 * usually not supported. 1759 * 1760 * The following commands are currently not supported: 1761 * 1762 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1763 * MT_ST_WRITE_THRESHOLD. 1764 */ 1765static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1766{ 1767 idetape_tape_t *tape = drive->driver_data; 1768 struct gendisk *disk = tape->disk; 1769 struct ide_atapi_pc pc; 1770 int i, retval; 1771 1772 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1773 mt_op, mt_count); 1774 1775 switch (mt_op) { 1776 case MTFSF: 1777 case MTFSFM: 1778 case MTBSF: 1779 case MTBSFM: 1780 if (!mt_count) 1781 return 0; 1782 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1783 default: 1784 break; 1785 } 1786 1787 switch (mt_op) { 1788 case MTWEOF: 1789 if (tape->write_prot) 1790 return -EACCES; 1791 ide_tape_discard_merge_buffer(drive, 1); 1792 for (i = 0; i < mt_count; i++) { 1793 retval = idetape_write_filemark(drive); 1794 if (retval) 1795 return retval; 1796 } 1797 return 0; 1798 case MTREW: 1799 ide_tape_discard_merge_buffer(drive, 0); 1800 if (idetape_rewind_tape(drive)) 1801 return -EIO; 1802 return 0; 1803 case MTLOAD: 1804 ide_tape_discard_merge_buffer(drive, 0); 1805 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1806 case MTUNLOAD: 1807 case MTOFFL: 1808 /* 1809 * If door is locked, attempt to unlock before 1810 * attempting to eject. 1811 */ 1812 if (tape->door_locked) { 1813 if (!ide_set_media_lock(drive, disk, 0)) 1814 tape->door_locked = DOOR_UNLOCKED; 1815 } 1816 ide_tape_discard_merge_buffer(drive, 0); 1817 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); 1818 if (!retval) 1819 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1820 return retval; 1821 case MTNOP: 1822 ide_tape_discard_merge_buffer(drive, 0); 1823 return idetape_flush_tape_buffers(drive); 1824 case MTRETEN: 1825 ide_tape_discard_merge_buffer(drive, 0); 1826 return ide_do_start_stop(drive, disk, 1827 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1828 case MTEOM: 1829 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1830 return ide_queue_pc_tail(drive, disk, &pc); 1831 case MTERASE: 1832 (void)idetape_rewind_tape(drive); 1833 idetape_create_erase_cmd(&pc); 1834 return ide_queue_pc_tail(drive, disk, &pc); 1835 case MTSETBLK: 1836 if (mt_count) { 1837 if (mt_count < tape->blk_size || 1838 mt_count % tape->blk_size) 1839 return -EIO; 1840 tape->user_bs_factor = mt_count / tape->blk_size; 1841 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1842 } else 1843 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1844 return 0; 1845 case MTSEEK: 1846 ide_tape_discard_merge_buffer(drive, 0); 1847 return idetape_position_tape(drive, 1848 mt_count * tape->user_bs_factor, tape->partition, 0); 1849 case MTSETPART: 1850 ide_tape_discard_merge_buffer(drive, 0); 1851 return idetape_position_tape(drive, 0, mt_count, 0); 1852 case MTFSR: 1853 case MTBSR: 1854 case MTLOCK: 1855 retval = ide_set_media_lock(drive, disk, 1); 1856 if (retval) 1857 return retval; 1858 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1859 return 0; 1860 case MTUNLOCK: 1861 retval = ide_set_media_lock(drive, disk, 0); 1862 if (retval) 1863 return retval; 1864 tape->door_locked = DOOR_UNLOCKED; 1865 return 0; 1866 default: 1867 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1868 mt_op); 1869 return -EIO; 1870 } 1871} 1872 1873/* 1874 * Our character device ioctls. General mtio.h magnetic io commands are 1875 * supported here, and not in the corresponding block interface. Our own 1876 * ide-tape ioctls are supported on both interfaces. 1877 */ 1878static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1879 unsigned int cmd, unsigned long arg) 1880{ 1881 struct ide_tape_obj *tape = ide_tape_f(file); 1882 ide_drive_t *drive = tape->drive; 1883 struct mtop mtop; 1884 struct mtget mtget; 1885 struct mtpos mtpos; 1886 int block_offset = 0, position = tape->first_frame; 1887 void __user *argp = (void __user *)arg; 1888 1889 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1890 1891 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1892 ide_tape_flush_merge_buffer(drive); 1893 idetape_flush_tape_buffers(drive); 1894 } 1895 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1896 block_offset = tape->merge_bh_size / 1897 (tape->blk_size * tape->user_bs_factor); 1898 position = idetape_read_position(drive); 1899 if (position < 0) 1900 return -EIO; 1901 } 1902 switch (cmd) { 1903 case MTIOCTOP: 1904 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1905 return -EFAULT; 1906 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1907 case MTIOCGET: 1908 memset(&mtget, 0, sizeof(struct mtget)); 1909 mtget.mt_type = MT_ISSCSI2; 1910 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1911 mtget.mt_dsreg = 1912 ((tape->blk_size * tape->user_bs_factor) 1913 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1914 1915 if (tape->drv_write_prot) 1916 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1917 1918 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1919 return -EFAULT; 1920 return 0; 1921 case MTIOCPOS: 1922 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1923 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1924 return -EFAULT; 1925 return 0; 1926 default: 1927 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1928 ide_tape_discard_merge_buffer(drive, 1); 1929 return idetape_blkdev_ioctl(drive, cmd, arg); 1930 } 1931} 1932 1933/* 1934 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1935 * block size with the reported value. 1936 */ 1937static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1938{ 1939 idetape_tape_t *tape = drive->driver_data; 1940 struct ide_atapi_pc pc; 1941 1942 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1943 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1944 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1945 if (tape->blk_size == 0) { 1946 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1947 "block size, assuming 32k\n"); 1948 tape->blk_size = 32768; 1949 } 1950 return; 1951 } 1952 tape->blk_size = (pc.buf[4 + 5] << 16) + 1953 (pc.buf[4 + 6] << 8) + 1954 pc.buf[4 + 7]; 1955 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1956} 1957 1958static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1959{ 1960 unsigned int minor = iminor(inode), i = minor & ~0xc0; 1961 ide_drive_t *drive; 1962 idetape_tape_t *tape; 1963 int retval; 1964 1965 if (i >= MAX_HWIFS * MAX_DRIVES) 1966 return -ENXIO; 1967 1968 lock_kernel(); 1969 tape = ide_tape_chrdev_get(i); 1970 if (!tape) { 1971 unlock_kernel(); 1972 return -ENXIO; 1973 } 1974 1975 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1976 1977 /* 1978 * We really want to do nonseekable_open(inode, filp); here, but some 1979 * versions of tar incorrectly call lseek on tapes and bail out if that 1980 * fails. So we disallow pread() and pwrite(), but permit lseeks. 1981 */ 1982 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 1983 1984 drive = tape->drive; 1985 1986 filp->private_data = tape; 1987 1988 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 1989 retval = -EBUSY; 1990 goto out_put_tape; 1991 } 1992 1993 retval = idetape_wait_ready(drive, 60 * HZ); 1994 if (retval) { 1995 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1996 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 1997 goto out_put_tape; 1998 } 1999 2000 idetape_read_position(drive); 2001 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 2002 (void)idetape_rewind_tape(drive); 2003 2004 /* Read block size and write protect status from drive. */ 2005 ide_tape_get_bsize_from_bdesc(drive); 2006 2007 /* Set write protect flag if device is opened as read-only. */ 2008 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 2009 tape->write_prot = 1; 2010 else 2011 tape->write_prot = tape->drv_write_prot; 2012 2013 /* Make sure drive isn't write protected if user wants to write. */ 2014 if (tape->write_prot) { 2015 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 2016 (filp->f_flags & O_ACCMODE) == O_RDWR) { 2017 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2018 retval = -EROFS; 2019 goto out_put_tape; 2020 } 2021 } 2022 2023 /* Lock the tape drive door so user can't eject. */ 2024 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2025 if (!ide_set_media_lock(drive, tape->disk, 1)) { 2026 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 2027 tape->door_locked = DOOR_LOCKED; 2028 } 2029 } 2030 unlock_kernel(); 2031 return 0; 2032 2033out_put_tape: 2034 ide_tape_put(tape); 2035 unlock_kernel(); 2036 return retval; 2037} 2038 2039static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 2040{ 2041 idetape_tape_t *tape = drive->driver_data; 2042 2043 ide_tape_flush_merge_buffer(drive); 2044 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 2045 if (tape->merge_bh != NULL) { 2046 idetape_pad_zeros(drive, tape->blk_size * 2047 (tape->user_bs_factor - 1)); 2048 ide_tape_kfree_buffer(tape); 2049 tape->merge_bh = NULL; 2050 } 2051 idetape_write_filemark(drive); 2052 idetape_flush_tape_buffers(drive); 2053 idetape_flush_tape_buffers(drive); 2054} 2055 2056static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2057{ 2058 struct ide_tape_obj *tape = ide_tape_f(filp); 2059 ide_drive_t *drive = tape->drive; 2060 unsigned int minor = iminor(inode); 2061 2062 lock_kernel(); 2063 tape = drive->driver_data; 2064 2065 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2066 2067 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2068 idetape_write_release(drive, minor); 2069 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2070 if (minor < 128) 2071 ide_tape_discard_merge_buffer(drive, 1); 2072 } 2073 2074 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 2075 (void) idetape_rewind_tape(drive); 2076 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2077 if (tape->door_locked == DOOR_LOCKED) { 2078 if (!ide_set_media_lock(drive, tape->disk, 0)) 2079 tape->door_locked = DOOR_UNLOCKED; 2080 } 2081 } 2082 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2083 ide_tape_put(tape); 2084 unlock_kernel(); 2085 return 0; 2086} 2087 2088static void idetape_get_inquiry_results(ide_drive_t *drive) 2089{ 2090 idetape_tape_t *tape = drive->driver_data; 2091 struct ide_atapi_pc pc; 2092 char fw_rev[4], vendor_id[8], product_id[16]; 2093 2094 idetape_create_inquiry_cmd(&pc); 2095 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2096 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2097 tape->name); 2098 return; 2099 } 2100 memcpy(vendor_id, &pc.buf[8], 8); 2101 memcpy(product_id, &pc.buf[16], 16); 2102 memcpy(fw_rev, &pc.buf[32], 4); 2103 2104 ide_fixstring(vendor_id, 8, 0); 2105 ide_fixstring(product_id, 16, 0); 2106 ide_fixstring(fw_rev, 4, 0); 2107 2108 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2109 drive->name, tape->name, vendor_id, product_id, fw_rev); 2110} 2111 2112/* 2113 * Ask the tape about its various parameters. In particular, we will adjust our 2114 * data transfer buffer size to the recommended value as returned by the tape. 2115 */ 2116static void idetape_get_mode_sense_results(ide_drive_t *drive) 2117{ 2118 idetape_tape_t *tape = drive->driver_data; 2119 struct ide_atapi_pc pc; 2120 u8 *caps; 2121 u8 speed, max_speed; 2122 2123 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2124 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2125 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2126 " some default values\n"); 2127 tape->blk_size = 512; 2128 put_unaligned(52, (u16 *)&tape->caps[12]); 2129 put_unaligned(540, (u16 *)&tape->caps[14]); 2130 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2131 return; 2132 } 2133 caps = pc.buf + 4 + pc.buf[3]; 2134 2135 /* convert to host order and save for later use */ 2136 speed = be16_to_cpup((__be16 *)&caps[14]); 2137 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2138 2139 *(u16 *)&caps[8] = max_speed; 2140 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2141 *(u16 *)&caps[14] = speed; 2142 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2143 2144 if (!speed) { 2145 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2146 "(assuming 650KB/sec)\n", drive->name); 2147 *(u16 *)&caps[14] = 650; 2148 } 2149 if (!max_speed) { 2150 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2151 "(assuming 650KB/sec)\n", drive->name); 2152 *(u16 *)&caps[8] = 650; 2153 } 2154 2155 memcpy(&tape->caps, caps, 20); 2156 2157 /* device lacks locking support according to capabilities page */ 2158 if ((caps[6] & 1) == 0) 2159 drive->atapi_flags |= IDE_AFLAG_NO_DOORLOCK; 2160 2161 if (caps[7] & 0x02) 2162 tape->blk_size = 512; 2163 else if (caps[7] & 0x04) 2164 tape->blk_size = 1024; 2165} 2166 2167#ifdef CONFIG_IDE_PROC_FS 2168#define ide_tape_devset_get(name, field) \ 2169static int get_##name(ide_drive_t *drive) \ 2170{ \ 2171 idetape_tape_t *tape = drive->driver_data; \ 2172 return tape->field; \ 2173} 2174 2175#define ide_tape_devset_set(name, field) \ 2176static int set_##name(ide_drive_t *drive, int arg) \ 2177{ \ 2178 idetape_tape_t *tape = drive->driver_data; \ 2179 tape->field = arg; \ 2180 return 0; \ 2181} 2182 2183#define ide_tape_devset_rw_field(_name, _field) \ 2184ide_tape_devset_get(_name, _field) \ 2185ide_tape_devset_set(_name, _field) \ 2186IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name) 2187 2188#define ide_tape_devset_r_field(_name, _field) \ 2189ide_tape_devset_get(_name, _field) \ 2190IDE_DEVSET(_name, 0, get_##_name, NULL) 2191 2192static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2193static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2194static int divf_buffer(ide_drive_t *drive) { return 2; } 2195static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2196 2197ide_devset_rw_field(dsc_overlap, dsc_overlap); 2198 2199ide_tape_devset_rw_field(debug_mask, debug_mask); 2200ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq); 2201 2202ide_tape_devset_r_field(avg_speed, avg_speed); 2203ide_tape_devset_r_field(speed, caps[14]); 2204ide_tape_devset_r_field(buffer, caps[16]); 2205ide_tape_devset_r_field(buffer_size, buffer_size); 2206 2207static const struct ide_proc_devset idetape_settings[] = { 2208 __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), 2209 __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), 2210 __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), 2211 __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), 2212 __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), 2213 __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), 2214 __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2215 mulf_tdsc, divf_tdsc), 2216 { 0 }, 2217}; 2218#endif 2219 2220/* 2221 * The function below is called to: 2222 * 2223 * 1. Initialize our various state variables. 2224 * 2. Ask the tape for its capabilities. 2225 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2226 * is chosen based on the recommendation which we received in step 2. 2227 * 2228 * Note that at this point ide.c already assigned us an irq, so that we can 2229 * queue requests here and wait for their completion. 2230 */ 2231static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2232{ 2233 unsigned long t; 2234 int speed; 2235 int buffer_size; 2236 u8 gcw[2]; 2237 u16 *ctl = (u16 *)&tape->caps[12]; 2238 2239 drive->pc_callback = ide_tape_callback; 2240 2241 spin_lock_init(&tape->lock); 2242 drive->dsc_overlap = 1; 2243 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2244 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2245 tape->name); 2246 drive->dsc_overlap = 0; 2247 } 2248 /* Seagate Travan drives do not support DSC overlap. */ 2249 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2250 drive->dsc_overlap = 0; 2251 tape->minor = minor; 2252 tape->name[0] = 'h'; 2253 tape->name[1] = 't'; 2254 tape->name[2] = '0' + minor; 2255 tape->chrdev_dir = IDETAPE_DIR_NONE; 2256 2257 *((u16 *)&gcw) = drive->id[ATA_ID_CONFIG]; 2258 2259 /* Command packet DRQ type */ 2260 if (((gcw[0] & 0x60) >> 5) == 1) 2261 set_bit(IDE_AFLAG_DRQ_INTERRUPT, &drive->atapi_flags); 2262 2263 idetape_get_inquiry_results(drive); 2264 idetape_get_mode_sense_results(drive); 2265 ide_tape_get_bsize_from_bdesc(drive); 2266 tape->user_bs_factor = 1; 2267 tape->buffer_size = *ctl * tape->blk_size; 2268 while (tape->buffer_size > 0xffff) { 2269 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2270 *ctl /= 2; 2271 tape->buffer_size = *ctl * tape->blk_size; 2272 } 2273 buffer_size = tape->buffer_size; 2274 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2275 if (buffer_size % PAGE_SIZE) { 2276 tape->pages_per_buffer++; 2277 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2278 } 2279 2280 /* select the "best" DSC read/write polling freq */ 2281 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2282 2283 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2284 2285 /* 2286 * Ensure that the number we got makes sense; limit it within 2287 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2288 */ 2289 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2290 IDETAPE_DSC_RW_MAX); 2291 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2292 "%lums tDSC%s\n", 2293 drive->name, tape->name, *(u16 *)&tape->caps[14], 2294 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2295 tape->buffer_size / 1024, 2296 tape->best_dsc_rw_freq * 1000 / HZ, 2297 drive->using_dma ? ", DMA":""); 2298 2299 ide_proc_register_driver(drive, tape->driver); 2300} 2301 2302static void ide_tape_remove(ide_drive_t *drive) 2303{ 2304 idetape_tape_t *tape = drive->driver_data; 2305 2306 ide_proc_unregister_driver(drive, tape->driver); 2307 2308 ide_unregister_region(tape->disk); 2309 2310 ide_tape_put(tape); 2311} 2312 2313static void ide_tape_release(struct kref *kref) 2314{ 2315 struct ide_tape_obj *tape = to_ide_tape(kref); 2316 ide_drive_t *drive = tape->drive; 2317 struct gendisk *g = tape->disk; 2318 2319 BUG_ON(tape->merge_bh_size); 2320 2321 drive->dsc_overlap = 0; 2322 drive->driver_data = NULL; 2323 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2324 device_destroy(idetape_sysfs_class, 2325 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2326 idetape_devs[tape->minor] = NULL; 2327 g->private_data = NULL; 2328 put_disk(g); 2329 kfree(tape); 2330} 2331 2332#ifdef CONFIG_IDE_PROC_FS 2333static int proc_idetape_read_name 2334 (char *page, char **start, off_t off, int count, int *eof, void *data) 2335{ 2336 ide_drive_t *drive = (ide_drive_t *) data; 2337 idetape_tape_t *tape = drive->driver_data; 2338 char *out = page; 2339 int len; 2340 2341 len = sprintf(out, "%s\n", tape->name); 2342 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2343} 2344 2345static ide_proc_entry_t idetape_proc[] = { 2346 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2347 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2348 { NULL, 0, NULL, NULL } 2349}; 2350#endif 2351 2352static int ide_tape_probe(ide_drive_t *); 2353 2354static ide_driver_t idetape_driver = { 2355 .gen_driver = { 2356 .owner = THIS_MODULE, 2357 .name = "ide-tape", 2358 .bus = &ide_bus_type, 2359 }, 2360 .probe = ide_tape_probe, 2361 .remove = ide_tape_remove, 2362 .version = IDETAPE_VERSION, 2363 .media = ide_tape, 2364 .do_request = idetape_do_request, 2365 .end_request = idetape_end_request, 2366 .error = __ide_error, 2367#ifdef CONFIG_IDE_PROC_FS 2368 .proc = idetape_proc, 2369 .settings = idetape_settings, 2370#endif 2371}; 2372 2373/* Our character device supporting functions, passed to register_chrdev. */ 2374static const struct file_operations idetape_fops = { 2375 .owner = THIS_MODULE, 2376 .read = idetape_chrdev_read, 2377 .write = idetape_chrdev_write, 2378 .ioctl = idetape_chrdev_ioctl, 2379 .open = idetape_chrdev_open, 2380 .release = idetape_chrdev_release, 2381}; 2382 2383static int idetape_open(struct inode *inode, struct file *filp) 2384{ 2385 struct gendisk *disk = inode->i_bdev->bd_disk; 2386 struct ide_tape_obj *tape; 2387 2388 tape = ide_tape_get(disk); 2389 if (!tape) 2390 return -ENXIO; 2391 2392 return 0; 2393} 2394 2395static int idetape_release(struct inode *inode, struct file *filp) 2396{ 2397 struct gendisk *disk = inode->i_bdev->bd_disk; 2398 struct ide_tape_obj *tape = ide_tape_g(disk); 2399 2400 ide_tape_put(tape); 2401 2402 return 0; 2403} 2404 2405static int idetape_ioctl(struct inode *inode, struct file *file, 2406 unsigned int cmd, unsigned long arg) 2407{ 2408 struct block_device *bdev = inode->i_bdev; 2409 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 2410 ide_drive_t *drive = tape->drive; 2411 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 2412 if (err == -EINVAL) 2413 err = idetape_blkdev_ioctl(drive, cmd, arg); 2414 return err; 2415} 2416 2417static struct block_device_operations idetape_block_ops = { 2418 .owner = THIS_MODULE, 2419 .open = idetape_open, 2420 .release = idetape_release, 2421 .ioctl = idetape_ioctl, 2422}; 2423 2424static int ide_tape_probe(ide_drive_t *drive) 2425{ 2426 idetape_tape_t *tape; 2427 struct gendisk *g; 2428 int minor; 2429 2430 if (!strstr("ide-tape", drive->driver_req)) 2431 goto failed; 2432 2433 if (drive->media != ide_tape) 2434 goto failed; 2435 2436 if (drive->id_read == 1 && !ide_check_atapi_device(drive, DRV_NAME)) { 2437 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2438 " the driver\n", drive->name); 2439 goto failed; 2440 } 2441 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2442 if (tape == NULL) { 2443 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2444 drive->name); 2445 goto failed; 2446 } 2447 2448 g = alloc_disk(1 << PARTN_BITS); 2449 if (!g) 2450 goto out_free_tape; 2451 2452 ide_init_disk(g, drive); 2453 2454 kref_init(&tape->kref); 2455 2456 tape->drive = drive; 2457 tape->driver = &idetape_driver; 2458 tape->disk = g; 2459 2460 g->private_data = &tape->driver; 2461 2462 drive->driver_data = tape; 2463 2464 mutex_lock(&idetape_ref_mutex); 2465 for (minor = 0; idetape_devs[minor]; minor++) 2466 ; 2467 idetape_devs[minor] = tape; 2468 mutex_unlock(&idetape_ref_mutex); 2469 2470 idetape_setup(drive, tape, minor); 2471 2472 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2473 MKDEV(IDETAPE_MAJOR, minor), NULL, 2474 "%s", tape->name); 2475 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2476 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2477 "n%s", tape->name); 2478 2479 g->fops = &idetape_block_ops; 2480 ide_register_region(g); 2481 2482 return 0; 2483 2484out_free_tape: 2485 kfree(tape); 2486failed: 2487 return -ENODEV; 2488} 2489 2490static void __exit idetape_exit(void) 2491{ 2492 driver_unregister(&idetape_driver.gen_driver); 2493 class_destroy(idetape_sysfs_class); 2494 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2495} 2496 2497static int __init idetape_init(void) 2498{ 2499 int error = 1; 2500 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2501 if (IS_ERR(idetape_sysfs_class)) { 2502 idetape_sysfs_class = NULL; 2503 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2504 error = -EBUSY; 2505 goto out; 2506 } 2507 2508 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2509 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2510 " interface\n"); 2511 error = -EBUSY; 2512 goto out_free_class; 2513 } 2514 2515 error = driver_register(&idetape_driver.gen_driver); 2516 if (error) 2517 goto out_free_driver; 2518 2519 return 0; 2520 2521out_free_driver: 2522 driver_unregister(&idetape_driver.gen_driver); 2523out_free_class: 2524 class_destroy(idetape_sysfs_class); 2525out: 2526 return error; 2527} 2528 2529MODULE_ALIAS("ide:*m-tape*"); 2530module_init(idetape_init); 2531module_exit(idetape_exit); 2532MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2533MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2534MODULE_LICENSE("GPL"); 2535