ide-tape.c revision 6902a5331256e1b9f4cef95a1e3622252113b260
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/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 156#define IDETAPE_BLOCK_DESCRIPTOR 0 157#define IDETAPE_CAPABILITIES_PAGE 0x2a 158 159/* 160 * Most of our global data which we need to save even as we leave the driver due 161 * to an interrupt or a timer event is stored in the struct defined below. 162 */ 163typedef struct ide_tape_obj { 164 ide_drive_t *drive; 165 struct ide_driver *driver; 166 struct gendisk *disk; 167 struct device dev; 168 169 /* used by REQ_IDETAPE_{READ,WRITE} requests */ 170 struct ide_atapi_pc queued_pc; 171 172 /* 173 * DSC polling variables. 174 * 175 * While polling for DSC we use postponed_rq to postpone the current 176 * request so that ide.c will be able to service pending requests on the 177 * other device. Note that at most we will have only one DSC (usually 178 * data transfer) request in the device request queue. 179 */ 180 struct request *postponed_rq; 181 /* The time in which we started polling for DSC */ 182 unsigned long dsc_polling_start; 183 /* Timer used to poll for dsc */ 184 struct timer_list dsc_timer; 185 /* Read/Write dsc polling frequency */ 186 unsigned long best_dsc_rw_freq; 187 unsigned long dsc_poll_freq; 188 unsigned long dsc_timeout; 189 190 /* Read position information */ 191 u8 partition; 192 /* Current block */ 193 unsigned int first_frame; 194 195 /* Last error information */ 196 u8 sense_key, asc, ascq; 197 198 /* Character device operation */ 199 unsigned int minor; 200 /* device name */ 201 char name[4]; 202 /* Current character device data transfer direction */ 203 u8 chrdev_dir; 204 205 /* tape block size, usually 512 or 1024 bytes */ 206 unsigned short blk_size; 207 int user_bs_factor; 208 209 /* Copy of the tape's Capabilities and Mechanical Page */ 210 u8 caps[20]; 211 212 /* 213 * Active data transfer request parameters. 214 * 215 * At most, there is only one ide-tape originated data transfer request 216 * in the device request queue. This allows ide.c to easily service 217 * requests from the other device when we postpone our active request. 218 */ 219 220 /* Data buffer size chosen based on the tape's recommendation */ 221 int buffer_size; 222 /* merge buffer */ 223 struct idetape_bh *merge_bh; 224 /* size of the merge buffer */ 225 int merge_bh_size; 226 /* pointer to current buffer head within the merge buffer */ 227 struct idetape_bh *bh; 228 char *b_data; 229 int b_count; 230 231 int pages_per_buffer; 232 /* Wasted space in each stage */ 233 int excess_bh_size; 234 235 /* Measures average tape speed */ 236 unsigned long avg_time; 237 int avg_size; 238 int avg_speed; 239 240 /* the door is currently locked */ 241 int door_locked; 242 /* the tape hardware is write protected */ 243 char drv_write_prot; 244 /* the tape is write protected (hardware or opened as read-only) */ 245 char write_prot; 246 247 u32 debug_mask; 248} idetape_tape_t; 249 250static DEFINE_MUTEX(idetape_ref_mutex); 251 252static struct class *idetape_sysfs_class; 253 254static void ide_tape_release(struct device *); 255 256static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 257{ 258 struct ide_tape_obj *tape = NULL; 259 260 mutex_lock(&idetape_ref_mutex); 261 tape = ide_drv_g(disk, ide_tape_obj); 262 if (tape) { 263 if (ide_device_get(tape->drive)) 264 tape = NULL; 265 else 266 get_device(&tape->dev); 267 } 268 mutex_unlock(&idetape_ref_mutex); 269 return tape; 270} 271 272static void ide_tape_put(struct ide_tape_obj *tape) 273{ 274 ide_drive_t *drive = tape->drive; 275 276 mutex_lock(&idetape_ref_mutex); 277 put_device(&tape->dev); 278 ide_device_put(drive); 279 mutex_unlock(&idetape_ref_mutex); 280} 281 282/* 283 * The variables below are used for the character device interface. Additional 284 * state variables are defined in our ide_drive_t structure. 285 */ 286static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES]; 287 288static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 289{ 290 struct ide_tape_obj *tape = NULL; 291 292 mutex_lock(&idetape_ref_mutex); 293 tape = idetape_devs[i]; 294 if (tape) 295 get_device(&tape->dev); 296 mutex_unlock(&idetape_ref_mutex); 297 return tape; 298} 299 300static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 301 unsigned int bcount) 302{ 303 struct idetape_bh *bh = pc->bh; 304 int count; 305 306 while (bcount) { 307 if (bh == NULL) { 308 printk(KERN_ERR "ide-tape: bh == NULL in " 309 "idetape_input_buffers\n"); 310 ide_pad_transfer(drive, 0, bcount); 311 return; 312 } 313 count = min( 314 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 315 bcount); 316 drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data + 317 atomic_read(&bh->b_count), count); 318 bcount -= count; 319 atomic_add(count, &bh->b_count); 320 if (atomic_read(&bh->b_count) == bh->b_size) { 321 bh = bh->b_reqnext; 322 if (bh) 323 atomic_set(&bh->b_count, 0); 324 } 325 } 326 pc->bh = bh; 327} 328 329static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 330 unsigned int bcount) 331{ 332 struct idetape_bh *bh = pc->bh; 333 int count; 334 335 while (bcount) { 336 if (bh == NULL) { 337 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 338 __func__); 339 return; 340 } 341 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 342 drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); 343 bcount -= count; 344 pc->b_data += count; 345 pc->b_count -= count; 346 if (!pc->b_count) { 347 bh = bh->b_reqnext; 348 pc->bh = bh; 349 if (bh) { 350 pc->b_data = bh->b_data; 351 pc->b_count = atomic_read(&bh->b_count); 352 } 353 } 354 } 355} 356 357static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) 358{ 359 struct idetape_bh *bh = pc->bh; 360 int count; 361 unsigned int bcount = pc->xferred; 362 363 if (pc->flags & PC_FLAG_WRITING) 364 return; 365 while (bcount) { 366 if (bh == NULL) { 367 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 368 __func__); 369 return; 370 } 371 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 372 atomic_set(&bh->b_count, count); 373 if (atomic_read(&bh->b_count) == bh->b_size) 374 bh = bh->b_reqnext; 375 bcount -= count; 376 } 377 pc->bh = bh; 378} 379 380/* 381 * called on each failed packet command retry to analyze the request sense. We 382 * currently do not utilize this information. 383 */ 384static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 385{ 386 idetape_tape_t *tape = drive->driver_data; 387 struct ide_atapi_pc *pc = drive->failed_pc; 388 389 tape->sense_key = sense[2] & 0xF; 390 tape->asc = sense[12]; 391 tape->ascq = sense[13]; 392 393 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 394 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 395 396 /* Correct pc->xferred by asking the tape. */ 397 if (pc->flags & PC_FLAG_DMA_ERROR) { 398 pc->xferred = pc->req_xfer - 399 tape->blk_size * 400 get_unaligned_be32(&sense[3]); 401 idetape_update_buffers(drive, pc); 402 } 403 404 /* 405 * If error was the result of a zero-length read or write command, 406 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 407 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 408 */ 409 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 410 /* length == 0 */ 411 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 412 if (tape->sense_key == 5) { 413 /* don't report an error, everything's ok */ 414 pc->error = 0; 415 /* don't retry read/write */ 416 pc->flags |= PC_FLAG_ABORT; 417 } 418 } 419 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 420 pc->error = IDE_DRV_ERROR_FILEMARK; 421 pc->flags |= PC_FLAG_ABORT; 422 } 423 if (pc->c[0] == WRITE_6) { 424 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 425 && tape->asc == 0x0 && tape->ascq == 0x2)) { 426 pc->error = IDE_DRV_ERROR_EOD; 427 pc->flags |= PC_FLAG_ABORT; 428 } 429 } 430 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 431 if (tape->sense_key == 8) { 432 pc->error = IDE_DRV_ERROR_EOD; 433 pc->flags |= PC_FLAG_ABORT; 434 } 435 if (!(pc->flags & PC_FLAG_ABORT) && 436 pc->xferred) 437 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 438 } 439} 440 441/* Free data buffers completely. */ 442static void ide_tape_kfree_buffer(idetape_tape_t *tape) 443{ 444 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 445 446 while (bh) { 447 u32 size = bh->b_size; 448 449 while (size) { 450 unsigned int order = fls(size >> PAGE_SHIFT)-1; 451 452 if (bh->b_data) 453 free_pages((unsigned long)bh->b_data, order); 454 455 size &= (order-1); 456 bh->b_data += (1 << order) * PAGE_SIZE; 457 } 458 prev_bh = bh; 459 bh = bh->b_reqnext; 460 kfree(prev_bh); 461 } 462} 463 464static void ide_tape_handle_dsc(ide_drive_t *); 465 466static int ide_tape_callback(ide_drive_t *drive, int dsc) 467{ 468 idetape_tape_t *tape = drive->driver_data; 469 struct ide_atapi_pc *pc = drive->pc; 470 struct request *rq = drive->hwif->rq; 471 int uptodate = pc->error ? 0 : 1; 472 int err = uptodate ? 0 : IDE_DRV_ERROR_GENERAL; 473 474 debug_log(DBG_PROCS, "Enter %s\n", __func__); 475 476 if (dsc) 477 ide_tape_handle_dsc(drive); 478 479 if (drive->failed_pc == pc) 480 drive->failed_pc = NULL; 481 482 if (pc->c[0] == REQUEST_SENSE) { 483 if (uptodate) 484 idetape_analyze_error(drive, pc->buf); 485 else 486 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 487 "itself - Aborting request!\n"); 488 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 489 int blocks = pc->xferred / tape->blk_size; 490 491 tape->avg_size += blocks * tape->blk_size; 492 493 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 494 tape->avg_speed = tape->avg_size * HZ / 495 (jiffies - tape->avg_time) / 1024; 496 tape->avg_size = 0; 497 tape->avg_time = jiffies; 498 } 499 500 tape->first_frame += blocks; 501 rq->current_nr_sectors -= blocks; 502 503 if (pc->error) { 504 uptodate = 0; 505 err = pc->error; 506 } 507 } else if (pc->c[0] == READ_POSITION && uptodate) { 508 u8 *readpos = pc->buf; 509 510 debug_log(DBG_SENSE, "BOP - %s\n", 511 (readpos[0] & 0x80) ? "Yes" : "No"); 512 debug_log(DBG_SENSE, "EOP - %s\n", 513 (readpos[0] & 0x40) ? "Yes" : "No"); 514 515 if (readpos[0] & 0x4) { 516 printk(KERN_INFO "ide-tape: Block location is unknown" 517 "to the tape\n"); 518 clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 519 uptodate = 0; 520 err = IDE_DRV_ERROR_GENERAL; 521 } else { 522 debug_log(DBG_SENSE, "Block Location - %u\n", 523 be32_to_cpup((__be32 *)&readpos[4])); 524 525 tape->partition = readpos[1]; 526 tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]); 527 set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 528 } 529 } 530 531 rq->errors = err; 532 533 return uptodate; 534} 535 536/* 537 * Postpone the current request so that ide.c will be able to service requests 538 * from another device on the same port while we are polling for DSC. 539 */ 540static void idetape_postpone_request(ide_drive_t *drive) 541{ 542 idetape_tape_t *tape = drive->driver_data; 543 544 debug_log(DBG_PROCS, "Enter %s\n", __func__); 545 546 tape->postponed_rq = drive->hwif->rq; 547 548 ide_stall_queue(drive, tape->dsc_poll_freq); 549} 550 551static void ide_tape_handle_dsc(ide_drive_t *drive) 552{ 553 idetape_tape_t *tape = drive->driver_data; 554 555 /* Media access command */ 556 tape->dsc_polling_start = jiffies; 557 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 558 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 559 /* Allow ide.c to handle other requests */ 560 idetape_postpone_request(drive); 561} 562 563static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 564 unsigned int bcount, int write) 565{ 566 if (write) 567 idetape_output_buffers(drive, pc, bcount); 568 else 569 idetape_input_buffers(drive, pc, bcount); 570 571 return bcount; 572} 573 574/* 575 * Packet Command Interface 576 * 577 * The current Packet Command is available in drive->pc, and will not change 578 * until we finish handling it. Each packet command is associated with a 579 * callback function that will be called when the command is finished. 580 * 581 * The handling will be done in three stages: 582 * 583 * 1. idetape_issue_pc will send the packet command to the drive, and will set 584 * the interrupt handler to ide_pc_intr. 585 * 586 * 2. On each interrupt, ide_pc_intr will be called. This step will be 587 * repeated until the device signals us that no more interrupts will be issued. 588 * 589 * 3. ATAPI Tape media access commands have immediate status with a delayed 590 * process. In case of a successful initiation of a media access packet command, 591 * the DSC bit will be set when the actual execution of the command is finished. 592 * Since the tape drive will not issue an interrupt, we have to poll for this 593 * event. In this case, we define the request as "low priority request" by 594 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 595 * exit the driver. 596 * 597 * ide.c will then give higher priority to requests which originate from the 598 * other device, until will change rq_status to RQ_ACTIVE. 599 * 600 * 4. When the packet command is finished, it will be checked for errors. 601 * 602 * 5. In case an error was found, we queue a request sense packet command in 603 * front of the request queue and retry the operation up to 604 * IDETAPE_MAX_PC_RETRIES times. 605 * 606 * 6. In case no error was found, or we decided to give up and not to retry 607 * again, the callback function will be called and then we will handle the next 608 * request. 609 */ 610 611static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 612 struct ide_atapi_pc *pc) 613{ 614 idetape_tape_t *tape = drive->driver_data; 615 616 if (drive->pc->c[0] == REQUEST_SENSE && 617 pc->c[0] == REQUEST_SENSE) { 618 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 619 "Two request sense in serial were issued\n"); 620 } 621 622 if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 623 drive->failed_pc = pc; 624 625 /* Set the current packet command */ 626 drive->pc = pc; 627 628 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 629 (pc->flags & PC_FLAG_ABORT)) { 630 /* 631 * We will "abort" retrying a packet command in case legitimate 632 * error code was received (crossing a filemark, or end of the 633 * media, for example). 634 */ 635 if (!(pc->flags & PC_FLAG_ABORT)) { 636 if (!(pc->c[0] == TEST_UNIT_READY && 637 tape->sense_key == 2 && tape->asc == 4 && 638 (tape->ascq == 1 || tape->ascq == 8))) { 639 printk(KERN_ERR "ide-tape: %s: I/O error, " 640 "pc = %2x, key = %2x, " 641 "asc = %2x, ascq = %2x\n", 642 tape->name, pc->c[0], 643 tape->sense_key, tape->asc, 644 tape->ascq); 645 } 646 /* Giving up */ 647 pc->error = IDE_DRV_ERROR_GENERAL; 648 } 649 drive->failed_pc = NULL; 650 drive->pc_callback(drive, 0); 651 return ide_stopped; 652 } 653 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 654 655 pc->retries++; 656 657 return ide_issue_pc(drive); 658} 659 660/* A mode sense command is used to "sense" tape parameters. */ 661static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 662{ 663 ide_init_pc(pc); 664 pc->c[0] = MODE_SENSE; 665 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 666 /* DBD = 1 - Don't return block descriptors */ 667 pc->c[1] = 8; 668 pc->c[2] = page_code; 669 /* 670 * Changed pc->c[3] to 0 (255 will at best return unused info). 671 * 672 * For SCSI this byte is defined as subpage instead of high byte 673 * of length and some IDE drives seem to interpret it this way 674 * and return an error when 255 is used. 675 */ 676 pc->c[3] = 0; 677 /* We will just discard data in that case */ 678 pc->c[4] = 255; 679 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 680 pc->req_xfer = 12; 681 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 682 pc->req_xfer = 24; 683 else 684 pc->req_xfer = 50; 685} 686 687static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 688{ 689 ide_hwif_t *hwif = drive->hwif; 690 idetape_tape_t *tape = drive->driver_data; 691 struct ide_atapi_pc *pc = drive->pc; 692 u8 stat; 693 694 stat = hwif->tp_ops->read_status(hwif); 695 696 if (stat & ATA_DSC) { 697 if (stat & ATA_ERR) { 698 /* Error detected */ 699 if (pc->c[0] != TEST_UNIT_READY) 700 printk(KERN_ERR "ide-tape: %s: I/O error, ", 701 tape->name); 702 /* Retry operation */ 703 ide_retry_pc(drive, tape->disk); 704 return ide_stopped; 705 } 706 pc->error = 0; 707 } else { 708 pc->error = IDE_DRV_ERROR_GENERAL; 709 drive->failed_pc = NULL; 710 } 711 drive->pc_callback(drive, 0); 712 return ide_stopped; 713} 714 715static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 716 struct ide_atapi_pc *pc, struct request *rq, 717 u8 opcode) 718{ 719 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 720 unsigned int length = rq->current_nr_sectors; 721 722 ide_init_pc(pc); 723 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 724 pc->c[1] = 1; 725 pc->bh = bh; 726 pc->buf = NULL; 727 pc->buf_size = length * tape->blk_size; 728 pc->req_xfer = pc->buf_size; 729 if (pc->req_xfer == tape->buffer_size) 730 pc->flags |= PC_FLAG_DMA_OK; 731 732 if (opcode == READ_6) { 733 pc->c[0] = READ_6; 734 atomic_set(&bh->b_count, 0); 735 } else if (opcode == WRITE_6) { 736 pc->c[0] = WRITE_6; 737 pc->flags |= PC_FLAG_WRITING; 738 pc->b_data = bh->b_data; 739 pc->b_count = atomic_read(&bh->b_count); 740 } 741 742 memcpy(rq->cmd, pc->c, 12); 743} 744 745static ide_startstop_t idetape_do_request(ide_drive_t *drive, 746 struct request *rq, sector_t block) 747{ 748 ide_hwif_t *hwif = drive->hwif; 749 idetape_tape_t *tape = drive->driver_data; 750 struct ide_atapi_pc *pc = NULL; 751 struct request *postponed_rq = tape->postponed_rq; 752 u8 stat; 753 754 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 755 " current_nr_sectors: %u\n", 756 (unsigned long long)rq->sector, rq->nr_sectors, 757 rq->current_nr_sectors); 758 759 if (!blk_special_request(rq)) { 760 /* We do not support buffer cache originated requests. */ 761 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 762 "request queue (%d)\n", drive->name, rq->cmd_type); 763 ide_end_request(drive, 0, 0); 764 return ide_stopped; 765 } 766 767 /* Retry a failed packet command */ 768 if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { 769 pc = drive->failed_pc; 770 goto out; 771 } 772 773 if (postponed_rq != NULL) 774 if (rq != postponed_rq) { 775 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 776 "Two DSC requests were queued\n"); 777 drive->failed_pc = NULL; 778 rq->errors = 0; 779 ide_complete_rq(drive, 0); 780 return ide_stopped; 781 } 782 783 tape->postponed_rq = NULL; 784 785 /* 786 * If the tape is still busy, postpone our request and service 787 * the other device meanwhile. 788 */ 789 stat = hwif->tp_ops->read_status(hwif); 790 791 if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 && 792 (rq->cmd[13] & REQ_IDETAPE_PC2) == 0) 793 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 794 795 if (drive->dev_flags & IDE_DFLAG_POST_RESET) { 796 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 797 drive->dev_flags &= ~IDE_DFLAG_POST_RESET; 798 } 799 800 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 801 (stat & ATA_DSC) == 0) { 802 if (postponed_rq == NULL) { 803 tape->dsc_polling_start = jiffies; 804 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 805 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 806 } else if (time_after(jiffies, tape->dsc_timeout)) { 807 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 808 tape->name); 809 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 810 idetape_media_access_finished(drive); 811 return ide_stopped; 812 } else { 813 return ide_do_reset(drive); 814 } 815 } else if (time_after(jiffies, 816 tape->dsc_polling_start + 817 IDETAPE_DSC_MA_THRESHOLD)) 818 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 819 idetape_postpone_request(drive); 820 return ide_stopped; 821 } 822 if (rq->cmd[13] & REQ_IDETAPE_READ) { 823 pc = &tape->queued_pc; 824 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 825 goto out; 826 } 827 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 828 pc = &tape->queued_pc; 829 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 830 goto out; 831 } 832 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 833 pc = (struct ide_atapi_pc *) rq->buffer; 834 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 835 rq->cmd[13] |= REQ_IDETAPE_PC2; 836 goto out; 837 } 838 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 839 idetape_media_access_finished(drive); 840 return ide_stopped; 841 } 842 BUG(); 843 844out: 845 return idetape_issue_pc(drive, pc); 846} 847 848/* 849 * The function below uses __get_free_pages to allocate a data buffer of size 850 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 851 * much as possible. 852 * 853 * It returns a pointer to the newly allocated buffer, or NULL in case of 854 * failure. 855 */ 856static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 857 int full, int clear) 858{ 859 struct idetape_bh *prev_bh, *bh, *merge_bh; 860 int pages = tape->pages_per_buffer; 861 unsigned int order, b_allocd; 862 char *b_data = NULL; 863 864 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 865 bh = merge_bh; 866 if (bh == NULL) 867 goto abort; 868 869 order = fls(pages) - 1; 870 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 871 if (!bh->b_data) 872 goto abort; 873 b_allocd = (1 << order) * PAGE_SIZE; 874 pages &= (order-1); 875 876 if (clear) 877 memset(bh->b_data, 0, b_allocd); 878 bh->b_reqnext = NULL; 879 bh->b_size = b_allocd; 880 atomic_set(&bh->b_count, full ? bh->b_size : 0); 881 882 while (pages) { 883 order = fls(pages) - 1; 884 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 885 if (!b_data) 886 goto abort; 887 b_allocd = (1 << order) * PAGE_SIZE; 888 889 if (clear) 890 memset(b_data, 0, b_allocd); 891 892 /* newly allocated page frames below buffer header or ...*/ 893 if (bh->b_data == b_data + b_allocd) { 894 bh->b_size += b_allocd; 895 bh->b_data -= b_allocd; 896 if (full) 897 atomic_add(b_allocd, &bh->b_count); 898 continue; 899 } 900 /* they are above the header */ 901 if (b_data == bh->b_data + bh->b_size) { 902 bh->b_size += b_allocd; 903 if (full) 904 atomic_add(b_allocd, &bh->b_count); 905 continue; 906 } 907 prev_bh = bh; 908 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 909 if (!bh) { 910 free_pages((unsigned long) b_data, order); 911 goto abort; 912 } 913 bh->b_reqnext = NULL; 914 bh->b_data = b_data; 915 bh->b_size = b_allocd; 916 atomic_set(&bh->b_count, full ? bh->b_size : 0); 917 prev_bh->b_reqnext = bh; 918 919 pages &= (order-1); 920 } 921 922 bh->b_size -= tape->excess_bh_size; 923 if (full) 924 atomic_sub(tape->excess_bh_size, &bh->b_count); 925 return merge_bh; 926abort: 927 ide_tape_kfree_buffer(tape); 928 return NULL; 929} 930 931static int idetape_copy_stage_from_user(idetape_tape_t *tape, 932 const char __user *buf, int n) 933{ 934 struct idetape_bh *bh = tape->bh; 935 int count; 936 int ret = 0; 937 938 while (n) { 939 if (bh == NULL) { 940 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 941 __func__); 942 return 1; 943 } 944 count = min((unsigned int) 945 (bh->b_size - atomic_read(&bh->b_count)), 946 (unsigned int)n); 947 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 948 count)) 949 ret = 1; 950 n -= count; 951 atomic_add(count, &bh->b_count); 952 buf += count; 953 if (atomic_read(&bh->b_count) == bh->b_size) { 954 bh = bh->b_reqnext; 955 if (bh) 956 atomic_set(&bh->b_count, 0); 957 } 958 } 959 tape->bh = bh; 960 return ret; 961} 962 963static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 964 int n) 965{ 966 struct idetape_bh *bh = tape->bh; 967 int count; 968 int ret = 0; 969 970 while (n) { 971 if (bh == NULL) { 972 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 973 __func__); 974 return 1; 975 } 976 count = min(tape->b_count, n); 977 if (copy_to_user(buf, tape->b_data, count)) 978 ret = 1; 979 n -= count; 980 tape->b_data += count; 981 tape->b_count -= count; 982 buf += count; 983 if (!tape->b_count) { 984 bh = bh->b_reqnext; 985 tape->bh = bh; 986 if (bh) { 987 tape->b_data = bh->b_data; 988 tape->b_count = atomic_read(&bh->b_count); 989 } 990 } 991 } 992 return ret; 993} 994 995static void idetape_init_merge_buffer(idetape_tape_t *tape) 996{ 997 struct idetape_bh *bh = tape->merge_bh; 998 tape->bh = tape->merge_bh; 999 1000 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1001 atomic_set(&bh->b_count, 0); 1002 else { 1003 tape->b_data = bh->b_data; 1004 tape->b_count = atomic_read(&bh->b_count); 1005 } 1006} 1007 1008/* 1009 * Write a filemark if write_filemark=1. Flush the device buffers without 1010 * writing a filemark otherwise. 1011 */ 1012static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1013 struct ide_atapi_pc *pc, int write_filemark) 1014{ 1015 ide_init_pc(pc); 1016 pc->c[0] = WRITE_FILEMARKS; 1017 pc->c[4] = write_filemark; 1018 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1019} 1020 1021static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1022{ 1023 idetape_tape_t *tape = drive->driver_data; 1024 struct gendisk *disk = tape->disk; 1025 int load_attempted = 0; 1026 1027 /* Wait for the tape to become ready */ 1028 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1029 timeout += jiffies; 1030 while (time_before(jiffies, timeout)) { 1031 if (ide_do_test_unit_ready(drive, disk) == 0) 1032 return 0; 1033 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1034 || (tape->asc == 0x3A)) { 1035 /* no media */ 1036 if (load_attempted) 1037 return -ENOMEDIUM; 1038 ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1039 load_attempted = 1; 1040 /* not about to be ready */ 1041 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1042 (tape->ascq == 1 || tape->ascq == 8))) 1043 return -EIO; 1044 msleep(100); 1045 } 1046 return -EIO; 1047} 1048 1049static int idetape_flush_tape_buffers(ide_drive_t *drive) 1050{ 1051 struct ide_tape_obj *tape = drive->driver_data; 1052 struct ide_atapi_pc pc; 1053 int rc; 1054 1055 idetape_create_write_filemark_cmd(drive, &pc, 0); 1056 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1057 if (rc) 1058 return rc; 1059 idetape_wait_ready(drive, 60 * 5 * HZ); 1060 return 0; 1061} 1062 1063static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1064{ 1065 ide_init_pc(pc); 1066 pc->c[0] = READ_POSITION; 1067 pc->req_xfer = 20; 1068} 1069 1070static int idetape_read_position(ide_drive_t *drive) 1071{ 1072 idetape_tape_t *tape = drive->driver_data; 1073 struct ide_atapi_pc pc; 1074 int position; 1075 1076 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1077 1078 idetape_create_read_position_cmd(&pc); 1079 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1080 return -1; 1081 position = tape->first_frame; 1082 return position; 1083} 1084 1085static void idetape_create_locate_cmd(ide_drive_t *drive, 1086 struct ide_atapi_pc *pc, 1087 unsigned int block, u8 partition, int skip) 1088{ 1089 ide_init_pc(pc); 1090 pc->c[0] = POSITION_TO_ELEMENT; 1091 pc->c[1] = 2; 1092 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1093 pc->c[8] = partition; 1094 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1095} 1096 1097static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1098{ 1099 idetape_tape_t *tape = drive->driver_data; 1100 1101 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1102 return; 1103 1104 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1105 tape->merge_bh_size = 0; 1106 if (tape->merge_bh != NULL) { 1107 ide_tape_kfree_buffer(tape); 1108 tape->merge_bh = NULL; 1109 } 1110 1111 tape->chrdev_dir = IDETAPE_DIR_NONE; 1112} 1113 1114/* 1115 * Position the tape to the requested block using the LOCATE packet command. 1116 * A READ POSITION command is then issued to check where we are positioned. Like 1117 * all higher level operations, we queue the commands at the tail of the request 1118 * queue and wait for their completion. 1119 */ 1120static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1121 u8 partition, int skip) 1122{ 1123 idetape_tape_t *tape = drive->driver_data; 1124 struct gendisk *disk = tape->disk; 1125 int retval; 1126 struct ide_atapi_pc pc; 1127 1128 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1129 __ide_tape_discard_merge_buffer(drive); 1130 idetape_wait_ready(drive, 60 * 5 * HZ); 1131 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1132 retval = ide_queue_pc_tail(drive, disk, &pc); 1133 if (retval) 1134 return (retval); 1135 1136 idetape_create_read_position_cmd(&pc); 1137 return ide_queue_pc_tail(drive, disk, &pc); 1138} 1139 1140static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1141 int restore_position) 1142{ 1143 idetape_tape_t *tape = drive->driver_data; 1144 int seek, position; 1145 1146 __ide_tape_discard_merge_buffer(drive); 1147 if (restore_position) { 1148 position = idetape_read_position(drive); 1149 seek = position > 0 ? position : 0; 1150 if (idetape_position_tape(drive, seek, 0, 0)) { 1151 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1152 " %s\n", tape->name, __func__); 1153 return; 1154 } 1155 } 1156} 1157 1158/* 1159 * Generate a read/write request for the block device interface and wait for it 1160 * to be serviced. 1161 */ 1162static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1163 struct idetape_bh *bh) 1164{ 1165 idetape_tape_t *tape = drive->driver_data; 1166 struct request *rq; 1167 int ret, errors; 1168 1169 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1170 1171 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1172 rq->cmd_type = REQ_TYPE_SPECIAL; 1173 rq->cmd[13] = cmd; 1174 rq->rq_disk = tape->disk; 1175 rq->special = (void *)bh; 1176 rq->sector = tape->first_frame; 1177 rq->nr_sectors = blocks; 1178 rq->current_nr_sectors = blocks; 1179 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1180 1181 errors = rq->errors; 1182 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1183 blk_put_request(rq); 1184 1185 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1186 return 0; 1187 1188 if (tape->merge_bh) 1189 idetape_init_merge_buffer(tape); 1190 if (errors == IDE_DRV_ERROR_GENERAL) 1191 return -EIO; 1192 return ret; 1193} 1194 1195static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1196{ 1197 ide_init_pc(pc); 1198 pc->c[0] = INQUIRY; 1199 pc->c[4] = 254; 1200 pc->req_xfer = 254; 1201} 1202 1203static void idetape_create_rewind_cmd(ide_drive_t *drive, 1204 struct ide_atapi_pc *pc) 1205{ 1206 ide_init_pc(pc); 1207 pc->c[0] = REZERO_UNIT; 1208 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1209} 1210 1211static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1212{ 1213 ide_init_pc(pc); 1214 pc->c[0] = ERASE; 1215 pc->c[1] = 1; 1216 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1217} 1218 1219static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1220{ 1221 ide_init_pc(pc); 1222 pc->c[0] = SPACE; 1223 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1224 pc->c[1] = cmd; 1225 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1226} 1227 1228/* Queue up a character device originated write request. */ 1229static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1230{ 1231 idetape_tape_t *tape = drive->driver_data; 1232 1233 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1234 1235 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1236 blocks, tape->merge_bh); 1237} 1238 1239static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1240{ 1241 idetape_tape_t *tape = drive->driver_data; 1242 int blocks, min; 1243 struct idetape_bh *bh; 1244 1245 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1246 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1247 " but we are not writing.\n"); 1248 return; 1249 } 1250 if (tape->merge_bh_size > tape->buffer_size) { 1251 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1252 tape->merge_bh_size = tape->buffer_size; 1253 } 1254 if (tape->merge_bh_size) { 1255 blocks = tape->merge_bh_size / tape->blk_size; 1256 if (tape->merge_bh_size % tape->blk_size) { 1257 unsigned int i; 1258 1259 blocks++; 1260 i = tape->blk_size - tape->merge_bh_size % 1261 tape->blk_size; 1262 bh = tape->bh->b_reqnext; 1263 while (bh) { 1264 atomic_set(&bh->b_count, 0); 1265 bh = bh->b_reqnext; 1266 } 1267 bh = tape->bh; 1268 while (i) { 1269 if (bh == NULL) { 1270 printk(KERN_INFO "ide-tape: bug," 1271 " bh NULL\n"); 1272 break; 1273 } 1274 min = min(i, (unsigned int)(bh->b_size - 1275 atomic_read(&bh->b_count))); 1276 memset(bh->b_data + atomic_read(&bh->b_count), 1277 0, min); 1278 atomic_add(min, &bh->b_count); 1279 i -= min; 1280 bh = bh->b_reqnext; 1281 } 1282 } 1283 (void) idetape_add_chrdev_write_request(drive, blocks); 1284 tape->merge_bh_size = 0; 1285 } 1286 if (tape->merge_bh != NULL) { 1287 ide_tape_kfree_buffer(tape); 1288 tape->merge_bh = NULL; 1289 } 1290 tape->chrdev_dir = IDETAPE_DIR_NONE; 1291} 1292 1293static int idetape_init_read(ide_drive_t *drive) 1294{ 1295 idetape_tape_t *tape = drive->driver_data; 1296 int bytes_read; 1297 1298 /* Initialize read operation */ 1299 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1300 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1301 ide_tape_flush_merge_buffer(drive); 1302 idetape_flush_tape_buffers(drive); 1303 } 1304 if (tape->merge_bh || tape->merge_bh_size) { 1305 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1306 " 0 now\n"); 1307 tape->merge_bh_size = 0; 1308 } 1309 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1310 if (!tape->merge_bh) 1311 return -ENOMEM; 1312 tape->chrdev_dir = IDETAPE_DIR_READ; 1313 1314 /* 1315 * Issue a read 0 command to ensure that DSC handshake is 1316 * switched from completion mode to buffer available mode. 1317 * No point in issuing this if DSC overlap isn't supported, some 1318 * drives (Seagate STT3401A) will return an error. 1319 */ 1320 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1321 bytes_read = idetape_queue_rw_tail(drive, 1322 REQ_IDETAPE_READ, 0, 1323 tape->merge_bh); 1324 if (bytes_read < 0) { 1325 ide_tape_kfree_buffer(tape); 1326 tape->merge_bh = NULL; 1327 tape->chrdev_dir = IDETAPE_DIR_NONE; 1328 return bytes_read; 1329 } 1330 } 1331 } 1332 1333 return 0; 1334} 1335 1336/* called from idetape_chrdev_read() to service a chrdev read request. */ 1337static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1338{ 1339 idetape_tape_t *tape = drive->driver_data; 1340 1341 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1342 1343 /* If we are at a filemark, return a read length of 0 */ 1344 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1345 return 0; 1346 1347 idetape_init_read(drive); 1348 1349 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1350 tape->merge_bh); 1351} 1352 1353static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1354{ 1355 idetape_tape_t *tape = drive->driver_data; 1356 struct idetape_bh *bh; 1357 int blocks; 1358 1359 while (bcount) { 1360 unsigned int count; 1361 1362 bh = tape->merge_bh; 1363 count = min(tape->buffer_size, bcount); 1364 bcount -= count; 1365 blocks = count / tape->blk_size; 1366 while (count) { 1367 atomic_set(&bh->b_count, 1368 min(count, (unsigned int)bh->b_size)); 1369 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1370 count -= atomic_read(&bh->b_count); 1371 bh = bh->b_reqnext; 1372 } 1373 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1374 tape->merge_bh); 1375 } 1376} 1377 1378/* 1379 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1380 * currently support only one partition. 1381 */ 1382static int idetape_rewind_tape(ide_drive_t *drive) 1383{ 1384 struct ide_tape_obj *tape = drive->driver_data; 1385 struct gendisk *disk = tape->disk; 1386 int retval; 1387 struct ide_atapi_pc pc; 1388 1389 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1390 1391 idetape_create_rewind_cmd(drive, &pc); 1392 retval = ide_queue_pc_tail(drive, disk, &pc); 1393 if (retval) 1394 return retval; 1395 1396 idetape_create_read_position_cmd(&pc); 1397 retval = ide_queue_pc_tail(drive, disk, &pc); 1398 if (retval) 1399 return retval; 1400 return 0; 1401} 1402 1403/* mtio.h compatible commands should be issued to the chrdev interface. */ 1404static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1405 unsigned long arg) 1406{ 1407 idetape_tape_t *tape = drive->driver_data; 1408 void __user *argp = (void __user *)arg; 1409 1410 struct idetape_config { 1411 int dsc_rw_frequency; 1412 int dsc_media_access_frequency; 1413 int nr_stages; 1414 } config; 1415 1416 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1417 1418 switch (cmd) { 1419 case 0x0340: 1420 if (copy_from_user(&config, argp, sizeof(config))) 1421 return -EFAULT; 1422 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1423 break; 1424 case 0x0350: 1425 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1426 config.nr_stages = 1; 1427 if (copy_to_user(argp, &config, sizeof(config))) 1428 return -EFAULT; 1429 break; 1430 default: 1431 return -EIO; 1432 } 1433 return 0; 1434} 1435 1436static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1437 int mt_count) 1438{ 1439 idetape_tape_t *tape = drive->driver_data; 1440 struct gendisk *disk = tape->disk; 1441 struct ide_atapi_pc pc; 1442 int retval, count = 0; 1443 int sprev = !!(tape->caps[4] & 0x20); 1444 1445 if (mt_count == 0) 1446 return 0; 1447 if (MTBSF == mt_op || MTBSFM == mt_op) { 1448 if (!sprev) 1449 return -EIO; 1450 mt_count = -mt_count; 1451 } 1452 1453 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1454 tape->merge_bh_size = 0; 1455 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1456 ++count; 1457 ide_tape_discard_merge_buffer(drive, 0); 1458 } 1459 1460 switch (mt_op) { 1461 case MTFSF: 1462 case MTBSF: 1463 idetape_create_space_cmd(&pc, mt_count - count, 1464 IDETAPE_SPACE_OVER_FILEMARK); 1465 return ide_queue_pc_tail(drive, disk, &pc); 1466 case MTFSFM: 1467 case MTBSFM: 1468 if (!sprev) 1469 return -EIO; 1470 retval = idetape_space_over_filemarks(drive, MTFSF, 1471 mt_count - count); 1472 if (retval) 1473 return retval; 1474 count = (MTBSFM == mt_op ? 1 : -1); 1475 return idetape_space_over_filemarks(drive, MTFSF, count); 1476 default: 1477 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1478 mt_op); 1479 return -EIO; 1480 } 1481} 1482 1483/* 1484 * Our character device read / write functions. 1485 * 1486 * The tape is optimized to maximize throughput when it is transferring an 1487 * integral number of the "continuous transfer limit", which is a parameter of 1488 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1489 * 1490 * As of version 1.3 of the driver, the character device provides an abstract 1491 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1492 * same backup/restore procedure is supported. The driver will internally 1493 * convert the requests to the recommended transfer unit, so that an unmatch 1494 * between the user's block size to the recommended size will only result in a 1495 * (slightly) increased driver overhead, but will no longer hit performance. 1496 * This is not applicable to Onstream. 1497 */ 1498static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1499 size_t count, loff_t *ppos) 1500{ 1501 struct ide_tape_obj *tape = file->private_data; 1502 ide_drive_t *drive = tape->drive; 1503 ssize_t bytes_read, temp, actually_read = 0, rc; 1504 ssize_t ret = 0; 1505 u16 ctl = *(u16 *)&tape->caps[12]; 1506 1507 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1508 1509 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1510 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1511 if (count > tape->blk_size && 1512 (count % tape->blk_size) == 0) 1513 tape->user_bs_factor = count / tape->blk_size; 1514 } 1515 rc = idetape_init_read(drive); 1516 if (rc < 0) 1517 return rc; 1518 if (count == 0) 1519 return (0); 1520 if (tape->merge_bh_size) { 1521 actually_read = min((unsigned int)(tape->merge_bh_size), 1522 (unsigned int)count); 1523 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1524 ret = -EFAULT; 1525 buf += actually_read; 1526 tape->merge_bh_size -= actually_read; 1527 count -= actually_read; 1528 } 1529 while (count >= tape->buffer_size) { 1530 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1531 if (bytes_read <= 0) 1532 goto finish; 1533 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1534 ret = -EFAULT; 1535 buf += bytes_read; 1536 count -= bytes_read; 1537 actually_read += bytes_read; 1538 } 1539 if (count) { 1540 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1541 if (bytes_read <= 0) 1542 goto finish; 1543 temp = min((unsigned long)count, (unsigned long)bytes_read); 1544 if (idetape_copy_stage_to_user(tape, buf, temp)) 1545 ret = -EFAULT; 1546 actually_read += temp; 1547 tape->merge_bh_size = bytes_read-temp; 1548 } 1549finish: 1550 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1551 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1552 1553 idetape_space_over_filemarks(drive, MTFSF, 1); 1554 return 0; 1555 } 1556 1557 return ret ? ret : actually_read; 1558} 1559 1560static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1561 size_t count, loff_t *ppos) 1562{ 1563 struct ide_tape_obj *tape = file->private_data; 1564 ide_drive_t *drive = tape->drive; 1565 ssize_t actually_written = 0; 1566 ssize_t ret = 0; 1567 u16 ctl = *(u16 *)&tape->caps[12]; 1568 1569 /* The drive is write protected. */ 1570 if (tape->write_prot) 1571 return -EACCES; 1572 1573 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1574 1575 /* Initialize write operation */ 1576 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1577 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1578 ide_tape_discard_merge_buffer(drive, 1); 1579 if (tape->merge_bh || tape->merge_bh_size) { 1580 printk(KERN_ERR "ide-tape: merge_bh_size " 1581 "should be 0 now\n"); 1582 tape->merge_bh_size = 0; 1583 } 1584 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1585 if (!tape->merge_bh) 1586 return -ENOMEM; 1587 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1588 idetape_init_merge_buffer(tape); 1589 1590 /* 1591 * Issue a write 0 command to ensure that DSC handshake is 1592 * switched from completion mode to buffer available mode. No 1593 * point in issuing this if DSC overlap isn't supported, some 1594 * drives (Seagate STT3401A) will return an error. 1595 */ 1596 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1597 ssize_t retval = idetape_queue_rw_tail(drive, 1598 REQ_IDETAPE_WRITE, 0, 1599 tape->merge_bh); 1600 if (retval < 0) { 1601 ide_tape_kfree_buffer(tape); 1602 tape->merge_bh = NULL; 1603 tape->chrdev_dir = IDETAPE_DIR_NONE; 1604 return retval; 1605 } 1606 } 1607 } 1608 if (count == 0) 1609 return (0); 1610 if (tape->merge_bh_size) { 1611 if (tape->merge_bh_size >= tape->buffer_size) { 1612 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1613 tape->merge_bh_size = 0; 1614 } 1615 actually_written = min((unsigned int) 1616 (tape->buffer_size - tape->merge_bh_size), 1617 (unsigned int)count); 1618 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1619 ret = -EFAULT; 1620 buf += actually_written; 1621 tape->merge_bh_size += actually_written; 1622 count -= actually_written; 1623 1624 if (tape->merge_bh_size == tape->buffer_size) { 1625 ssize_t retval; 1626 tape->merge_bh_size = 0; 1627 retval = idetape_add_chrdev_write_request(drive, ctl); 1628 if (retval <= 0) 1629 return (retval); 1630 } 1631 } 1632 while (count >= tape->buffer_size) { 1633 ssize_t retval; 1634 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1635 ret = -EFAULT; 1636 buf += tape->buffer_size; 1637 count -= tape->buffer_size; 1638 retval = idetape_add_chrdev_write_request(drive, ctl); 1639 actually_written += tape->buffer_size; 1640 if (retval <= 0) 1641 return (retval); 1642 } 1643 if (count) { 1644 actually_written += count; 1645 if (idetape_copy_stage_from_user(tape, buf, count)) 1646 ret = -EFAULT; 1647 tape->merge_bh_size += count; 1648 } 1649 return ret ? ret : actually_written; 1650} 1651 1652static int idetape_write_filemark(ide_drive_t *drive) 1653{ 1654 struct ide_tape_obj *tape = drive->driver_data; 1655 struct ide_atapi_pc pc; 1656 1657 /* Write a filemark */ 1658 idetape_create_write_filemark_cmd(drive, &pc, 1); 1659 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1660 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1661 return -EIO; 1662 } 1663 return 0; 1664} 1665 1666/* 1667 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1668 * requested. 1669 * 1670 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1671 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1672 * usually not supported. 1673 * 1674 * The following commands are currently not supported: 1675 * 1676 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1677 * MT_ST_WRITE_THRESHOLD. 1678 */ 1679static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1680{ 1681 idetape_tape_t *tape = drive->driver_data; 1682 struct gendisk *disk = tape->disk; 1683 struct ide_atapi_pc pc; 1684 int i, retval; 1685 1686 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1687 mt_op, mt_count); 1688 1689 switch (mt_op) { 1690 case MTFSF: 1691 case MTFSFM: 1692 case MTBSF: 1693 case MTBSFM: 1694 if (!mt_count) 1695 return 0; 1696 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1697 default: 1698 break; 1699 } 1700 1701 switch (mt_op) { 1702 case MTWEOF: 1703 if (tape->write_prot) 1704 return -EACCES; 1705 ide_tape_discard_merge_buffer(drive, 1); 1706 for (i = 0; i < mt_count; i++) { 1707 retval = idetape_write_filemark(drive); 1708 if (retval) 1709 return retval; 1710 } 1711 return 0; 1712 case MTREW: 1713 ide_tape_discard_merge_buffer(drive, 0); 1714 if (idetape_rewind_tape(drive)) 1715 return -EIO; 1716 return 0; 1717 case MTLOAD: 1718 ide_tape_discard_merge_buffer(drive, 0); 1719 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1720 case MTUNLOAD: 1721 case MTOFFL: 1722 /* 1723 * If door is locked, attempt to unlock before 1724 * attempting to eject. 1725 */ 1726 if (tape->door_locked) { 1727 if (!ide_set_media_lock(drive, disk, 0)) 1728 tape->door_locked = DOOR_UNLOCKED; 1729 } 1730 ide_tape_discard_merge_buffer(drive, 0); 1731 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); 1732 if (!retval) 1733 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1734 return retval; 1735 case MTNOP: 1736 ide_tape_discard_merge_buffer(drive, 0); 1737 return idetape_flush_tape_buffers(drive); 1738 case MTRETEN: 1739 ide_tape_discard_merge_buffer(drive, 0); 1740 return ide_do_start_stop(drive, disk, 1741 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1742 case MTEOM: 1743 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1744 return ide_queue_pc_tail(drive, disk, &pc); 1745 case MTERASE: 1746 (void)idetape_rewind_tape(drive); 1747 idetape_create_erase_cmd(&pc); 1748 return ide_queue_pc_tail(drive, disk, &pc); 1749 case MTSETBLK: 1750 if (mt_count) { 1751 if (mt_count < tape->blk_size || 1752 mt_count % tape->blk_size) 1753 return -EIO; 1754 tape->user_bs_factor = mt_count / tape->blk_size; 1755 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1756 } else 1757 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1758 return 0; 1759 case MTSEEK: 1760 ide_tape_discard_merge_buffer(drive, 0); 1761 return idetape_position_tape(drive, 1762 mt_count * tape->user_bs_factor, tape->partition, 0); 1763 case MTSETPART: 1764 ide_tape_discard_merge_buffer(drive, 0); 1765 return idetape_position_tape(drive, 0, mt_count, 0); 1766 case MTFSR: 1767 case MTBSR: 1768 case MTLOCK: 1769 retval = ide_set_media_lock(drive, disk, 1); 1770 if (retval) 1771 return retval; 1772 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1773 return 0; 1774 case MTUNLOCK: 1775 retval = ide_set_media_lock(drive, disk, 0); 1776 if (retval) 1777 return retval; 1778 tape->door_locked = DOOR_UNLOCKED; 1779 return 0; 1780 default: 1781 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1782 mt_op); 1783 return -EIO; 1784 } 1785} 1786 1787/* 1788 * Our character device ioctls. General mtio.h magnetic io commands are 1789 * supported here, and not in the corresponding block interface. Our own 1790 * ide-tape ioctls are supported on both interfaces. 1791 */ 1792static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1793 unsigned int cmd, unsigned long arg) 1794{ 1795 struct ide_tape_obj *tape = file->private_data; 1796 ide_drive_t *drive = tape->drive; 1797 struct mtop mtop; 1798 struct mtget mtget; 1799 struct mtpos mtpos; 1800 int block_offset = 0, position = tape->first_frame; 1801 void __user *argp = (void __user *)arg; 1802 1803 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1804 1805 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1806 ide_tape_flush_merge_buffer(drive); 1807 idetape_flush_tape_buffers(drive); 1808 } 1809 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1810 block_offset = tape->merge_bh_size / 1811 (tape->blk_size * tape->user_bs_factor); 1812 position = idetape_read_position(drive); 1813 if (position < 0) 1814 return -EIO; 1815 } 1816 switch (cmd) { 1817 case MTIOCTOP: 1818 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1819 return -EFAULT; 1820 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1821 case MTIOCGET: 1822 memset(&mtget, 0, sizeof(struct mtget)); 1823 mtget.mt_type = MT_ISSCSI2; 1824 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1825 mtget.mt_dsreg = 1826 ((tape->blk_size * tape->user_bs_factor) 1827 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1828 1829 if (tape->drv_write_prot) 1830 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1831 1832 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1833 return -EFAULT; 1834 return 0; 1835 case MTIOCPOS: 1836 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1837 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1838 return -EFAULT; 1839 return 0; 1840 default: 1841 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1842 ide_tape_discard_merge_buffer(drive, 1); 1843 return idetape_blkdev_ioctl(drive, cmd, arg); 1844 } 1845} 1846 1847/* 1848 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1849 * block size with the reported value. 1850 */ 1851static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1852{ 1853 idetape_tape_t *tape = drive->driver_data; 1854 struct ide_atapi_pc pc; 1855 1856 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1857 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1858 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1859 if (tape->blk_size == 0) { 1860 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1861 "block size, assuming 32k\n"); 1862 tape->blk_size = 32768; 1863 } 1864 return; 1865 } 1866 tape->blk_size = (pc.buf[4 + 5] << 16) + 1867 (pc.buf[4 + 6] << 8) + 1868 pc.buf[4 + 7]; 1869 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1870} 1871 1872static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1873{ 1874 unsigned int minor = iminor(inode), i = minor & ~0xc0; 1875 ide_drive_t *drive; 1876 idetape_tape_t *tape; 1877 int retval; 1878 1879 if (i >= MAX_HWIFS * MAX_DRIVES) 1880 return -ENXIO; 1881 1882 lock_kernel(); 1883 tape = ide_tape_chrdev_get(i); 1884 if (!tape) { 1885 unlock_kernel(); 1886 return -ENXIO; 1887 } 1888 1889 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1890 1891 /* 1892 * We really want to do nonseekable_open(inode, filp); here, but some 1893 * versions of tar incorrectly call lseek on tapes and bail out if that 1894 * fails. So we disallow pread() and pwrite(), but permit lseeks. 1895 */ 1896 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 1897 1898 drive = tape->drive; 1899 1900 filp->private_data = tape; 1901 1902 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 1903 retval = -EBUSY; 1904 goto out_put_tape; 1905 } 1906 1907 retval = idetape_wait_ready(drive, 60 * HZ); 1908 if (retval) { 1909 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1910 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 1911 goto out_put_tape; 1912 } 1913 1914 idetape_read_position(drive); 1915 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 1916 (void)idetape_rewind_tape(drive); 1917 1918 /* Read block size and write protect status from drive. */ 1919 ide_tape_get_bsize_from_bdesc(drive); 1920 1921 /* Set write protect flag if device is opened as read-only. */ 1922 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 1923 tape->write_prot = 1; 1924 else 1925 tape->write_prot = tape->drv_write_prot; 1926 1927 /* Make sure drive isn't write protected if user wants to write. */ 1928 if (tape->write_prot) { 1929 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 1930 (filp->f_flags & O_ACCMODE) == O_RDWR) { 1931 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1932 retval = -EROFS; 1933 goto out_put_tape; 1934 } 1935 } 1936 1937 /* Lock the tape drive door so user can't eject. */ 1938 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1939 if (!ide_set_media_lock(drive, tape->disk, 1)) { 1940 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 1941 tape->door_locked = DOOR_LOCKED; 1942 } 1943 } 1944 unlock_kernel(); 1945 return 0; 1946 1947out_put_tape: 1948 ide_tape_put(tape); 1949 unlock_kernel(); 1950 return retval; 1951} 1952 1953static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 1954{ 1955 idetape_tape_t *tape = drive->driver_data; 1956 1957 ide_tape_flush_merge_buffer(drive); 1958 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 1959 if (tape->merge_bh != NULL) { 1960 idetape_pad_zeros(drive, tape->blk_size * 1961 (tape->user_bs_factor - 1)); 1962 ide_tape_kfree_buffer(tape); 1963 tape->merge_bh = NULL; 1964 } 1965 idetape_write_filemark(drive); 1966 idetape_flush_tape_buffers(drive); 1967 idetape_flush_tape_buffers(drive); 1968} 1969 1970static int idetape_chrdev_release(struct inode *inode, struct file *filp) 1971{ 1972 struct ide_tape_obj *tape = filp->private_data; 1973 ide_drive_t *drive = tape->drive; 1974 unsigned int minor = iminor(inode); 1975 1976 lock_kernel(); 1977 tape = drive->driver_data; 1978 1979 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1980 1981 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1982 idetape_write_release(drive, minor); 1983 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1984 if (minor < 128) 1985 ide_tape_discard_merge_buffer(drive, 1); 1986 } 1987 1988 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 1989 (void) idetape_rewind_tape(drive); 1990 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1991 if (tape->door_locked == DOOR_LOCKED) { 1992 if (!ide_set_media_lock(drive, tape->disk, 0)) 1993 tape->door_locked = DOOR_UNLOCKED; 1994 } 1995 } 1996 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1997 ide_tape_put(tape); 1998 unlock_kernel(); 1999 return 0; 2000} 2001 2002static void idetape_get_inquiry_results(ide_drive_t *drive) 2003{ 2004 idetape_tape_t *tape = drive->driver_data; 2005 struct ide_atapi_pc pc; 2006 char fw_rev[4], vendor_id[8], product_id[16]; 2007 2008 idetape_create_inquiry_cmd(&pc); 2009 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2010 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2011 tape->name); 2012 return; 2013 } 2014 memcpy(vendor_id, &pc.buf[8], 8); 2015 memcpy(product_id, &pc.buf[16], 16); 2016 memcpy(fw_rev, &pc.buf[32], 4); 2017 2018 ide_fixstring(vendor_id, 8, 0); 2019 ide_fixstring(product_id, 16, 0); 2020 ide_fixstring(fw_rev, 4, 0); 2021 2022 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2023 drive->name, tape->name, vendor_id, product_id, fw_rev); 2024} 2025 2026/* 2027 * Ask the tape about its various parameters. In particular, we will adjust our 2028 * data transfer buffer size to the recommended value as returned by the tape. 2029 */ 2030static void idetape_get_mode_sense_results(ide_drive_t *drive) 2031{ 2032 idetape_tape_t *tape = drive->driver_data; 2033 struct ide_atapi_pc pc; 2034 u8 *caps; 2035 u8 speed, max_speed; 2036 2037 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2038 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2039 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2040 " some default values\n"); 2041 tape->blk_size = 512; 2042 put_unaligned(52, (u16 *)&tape->caps[12]); 2043 put_unaligned(540, (u16 *)&tape->caps[14]); 2044 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2045 return; 2046 } 2047 caps = pc.buf + 4 + pc.buf[3]; 2048 2049 /* convert to host order and save for later use */ 2050 speed = be16_to_cpup((__be16 *)&caps[14]); 2051 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2052 2053 *(u16 *)&caps[8] = max_speed; 2054 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2055 *(u16 *)&caps[14] = speed; 2056 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2057 2058 if (!speed) { 2059 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2060 "(assuming 650KB/sec)\n", drive->name); 2061 *(u16 *)&caps[14] = 650; 2062 } 2063 if (!max_speed) { 2064 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2065 "(assuming 650KB/sec)\n", drive->name); 2066 *(u16 *)&caps[8] = 650; 2067 } 2068 2069 memcpy(&tape->caps, caps, 20); 2070 2071 /* device lacks locking support according to capabilities page */ 2072 if ((caps[6] & 1) == 0) 2073 drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING; 2074 2075 if (caps[7] & 0x02) 2076 tape->blk_size = 512; 2077 else if (caps[7] & 0x04) 2078 tape->blk_size = 1024; 2079} 2080 2081#ifdef CONFIG_IDE_PROC_FS 2082#define ide_tape_devset_get(name, field) \ 2083static int get_##name(ide_drive_t *drive) \ 2084{ \ 2085 idetape_tape_t *tape = drive->driver_data; \ 2086 return tape->field; \ 2087} 2088 2089#define ide_tape_devset_set(name, field) \ 2090static int set_##name(ide_drive_t *drive, int arg) \ 2091{ \ 2092 idetape_tape_t *tape = drive->driver_data; \ 2093 tape->field = arg; \ 2094 return 0; \ 2095} 2096 2097#define ide_tape_devset_rw_field(_name, _field) \ 2098ide_tape_devset_get(_name, _field) \ 2099ide_tape_devset_set(_name, _field) \ 2100IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name) 2101 2102#define ide_tape_devset_r_field(_name, _field) \ 2103ide_tape_devset_get(_name, _field) \ 2104IDE_DEVSET(_name, 0, get_##_name, NULL) 2105 2106static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2107static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2108static int divf_buffer(ide_drive_t *drive) { return 2; } 2109static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2110 2111ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP); 2112 2113ide_tape_devset_rw_field(debug_mask, debug_mask); 2114ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq); 2115 2116ide_tape_devset_r_field(avg_speed, avg_speed); 2117ide_tape_devset_r_field(speed, caps[14]); 2118ide_tape_devset_r_field(buffer, caps[16]); 2119ide_tape_devset_r_field(buffer_size, buffer_size); 2120 2121static const struct ide_proc_devset idetape_settings[] = { 2122 __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), 2123 __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), 2124 __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), 2125 __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), 2126 __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), 2127 __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), 2128 __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2129 mulf_tdsc, divf_tdsc), 2130 { NULL }, 2131}; 2132#endif 2133 2134/* 2135 * The function below is called to: 2136 * 2137 * 1. Initialize our various state variables. 2138 * 2. Ask the tape for its capabilities. 2139 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2140 * is chosen based on the recommendation which we received in step 2. 2141 * 2142 * Note that at this point ide.c already assigned us an irq, so that we can 2143 * queue requests here and wait for their completion. 2144 */ 2145static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2146{ 2147 unsigned long t; 2148 int speed; 2149 int buffer_size; 2150 u16 *ctl = (u16 *)&tape->caps[12]; 2151 2152 drive->pc_callback = ide_tape_callback; 2153 drive->pc_update_buffers = idetape_update_buffers; 2154 drive->pc_io_buffers = ide_tape_io_buffers; 2155 2156 drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP; 2157 2158 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2159 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2160 tape->name); 2161 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2162 } 2163 2164 /* Seagate Travan drives do not support DSC overlap. */ 2165 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2166 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2167 2168 tape->minor = minor; 2169 tape->name[0] = 'h'; 2170 tape->name[1] = 't'; 2171 tape->name[2] = '0' + minor; 2172 tape->chrdev_dir = IDETAPE_DIR_NONE; 2173 2174 idetape_get_inquiry_results(drive); 2175 idetape_get_mode_sense_results(drive); 2176 ide_tape_get_bsize_from_bdesc(drive); 2177 tape->user_bs_factor = 1; 2178 tape->buffer_size = *ctl * tape->blk_size; 2179 while (tape->buffer_size > 0xffff) { 2180 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2181 *ctl /= 2; 2182 tape->buffer_size = *ctl * tape->blk_size; 2183 } 2184 buffer_size = tape->buffer_size; 2185 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2186 if (buffer_size % PAGE_SIZE) { 2187 tape->pages_per_buffer++; 2188 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2189 } 2190 2191 /* select the "best" DSC read/write polling freq */ 2192 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2193 2194 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2195 2196 /* 2197 * Ensure that the number we got makes sense; limit it within 2198 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2199 */ 2200 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2201 IDETAPE_DSC_RW_MAX); 2202 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2203 "%lums tDSC%s\n", 2204 drive->name, tape->name, *(u16 *)&tape->caps[14], 2205 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2206 tape->buffer_size / 1024, 2207 tape->best_dsc_rw_freq * 1000 / HZ, 2208 (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : ""); 2209 2210 ide_proc_register_driver(drive, tape->driver); 2211} 2212 2213static void ide_tape_remove(ide_drive_t *drive) 2214{ 2215 idetape_tape_t *tape = drive->driver_data; 2216 2217 ide_proc_unregister_driver(drive, tape->driver); 2218 device_del(&tape->dev); 2219 ide_unregister_region(tape->disk); 2220 2221 mutex_lock(&idetape_ref_mutex); 2222 put_device(&tape->dev); 2223 mutex_unlock(&idetape_ref_mutex); 2224} 2225 2226static void ide_tape_release(struct device *dev) 2227{ 2228 struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj); 2229 ide_drive_t *drive = tape->drive; 2230 struct gendisk *g = tape->disk; 2231 2232 BUG_ON(tape->merge_bh_size); 2233 2234 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2235 drive->driver_data = NULL; 2236 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2237 device_destroy(idetape_sysfs_class, 2238 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2239 idetape_devs[tape->minor] = NULL; 2240 g->private_data = NULL; 2241 put_disk(g); 2242 kfree(tape); 2243} 2244 2245#ifdef CONFIG_IDE_PROC_FS 2246static int proc_idetape_read_name 2247 (char *page, char **start, off_t off, int count, int *eof, void *data) 2248{ 2249 ide_drive_t *drive = (ide_drive_t *) data; 2250 idetape_tape_t *tape = drive->driver_data; 2251 char *out = page; 2252 int len; 2253 2254 len = sprintf(out, "%s\n", tape->name); 2255 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2256} 2257 2258static ide_proc_entry_t idetape_proc[] = { 2259 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2260 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2261 { NULL, 0, NULL, NULL } 2262}; 2263 2264static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive) 2265{ 2266 return idetape_proc; 2267} 2268 2269static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive) 2270{ 2271 return idetape_settings; 2272} 2273#endif 2274 2275static int ide_tape_probe(ide_drive_t *); 2276 2277static struct ide_driver idetape_driver = { 2278 .gen_driver = { 2279 .owner = THIS_MODULE, 2280 .name = "ide-tape", 2281 .bus = &ide_bus_type, 2282 }, 2283 .probe = ide_tape_probe, 2284 .remove = ide_tape_remove, 2285 .version = IDETAPE_VERSION, 2286 .do_request = idetape_do_request, 2287#ifdef CONFIG_IDE_PROC_FS 2288 .proc_entries = ide_tape_proc_entries, 2289 .proc_devsets = ide_tape_proc_devsets, 2290#endif 2291}; 2292 2293/* Our character device supporting functions, passed to register_chrdev. */ 2294static const struct file_operations idetape_fops = { 2295 .owner = THIS_MODULE, 2296 .read = idetape_chrdev_read, 2297 .write = idetape_chrdev_write, 2298 .ioctl = idetape_chrdev_ioctl, 2299 .open = idetape_chrdev_open, 2300 .release = idetape_chrdev_release, 2301}; 2302 2303static int idetape_open(struct block_device *bdev, fmode_t mode) 2304{ 2305 struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk); 2306 2307 if (!tape) 2308 return -ENXIO; 2309 2310 return 0; 2311} 2312 2313static int idetape_release(struct gendisk *disk, fmode_t mode) 2314{ 2315 struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj); 2316 2317 ide_tape_put(tape); 2318 return 0; 2319} 2320 2321static int idetape_ioctl(struct block_device *bdev, fmode_t mode, 2322 unsigned int cmd, unsigned long arg) 2323{ 2324 struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj); 2325 ide_drive_t *drive = tape->drive; 2326 int err = generic_ide_ioctl(drive, bdev, cmd, arg); 2327 if (err == -EINVAL) 2328 err = idetape_blkdev_ioctl(drive, cmd, arg); 2329 return err; 2330} 2331 2332static struct block_device_operations idetape_block_ops = { 2333 .owner = THIS_MODULE, 2334 .open = idetape_open, 2335 .release = idetape_release, 2336 .locked_ioctl = idetape_ioctl, 2337}; 2338 2339static int ide_tape_probe(ide_drive_t *drive) 2340{ 2341 idetape_tape_t *tape; 2342 struct gendisk *g; 2343 int minor; 2344 2345 if (!strstr("ide-tape", drive->driver_req)) 2346 goto failed; 2347 2348 if (drive->media != ide_tape) 2349 goto failed; 2350 2351 if ((drive->dev_flags & IDE_DFLAG_ID_READ) && 2352 ide_check_atapi_device(drive, DRV_NAME) == 0) { 2353 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2354 " the driver\n", drive->name); 2355 goto failed; 2356 } 2357 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2358 if (tape == NULL) { 2359 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2360 drive->name); 2361 goto failed; 2362 } 2363 2364 g = alloc_disk(1 << PARTN_BITS); 2365 if (!g) 2366 goto out_free_tape; 2367 2368 ide_init_disk(g, drive); 2369 2370 tape->dev.parent = &drive->gendev; 2371 tape->dev.release = ide_tape_release; 2372 dev_set_name(&tape->dev, dev_name(&drive->gendev)); 2373 2374 if (device_register(&tape->dev)) 2375 goto out_free_disk; 2376 2377 tape->drive = drive; 2378 tape->driver = &idetape_driver; 2379 tape->disk = g; 2380 2381 g->private_data = &tape->driver; 2382 2383 drive->driver_data = tape; 2384 2385 mutex_lock(&idetape_ref_mutex); 2386 for (minor = 0; idetape_devs[minor]; minor++) 2387 ; 2388 idetape_devs[minor] = tape; 2389 mutex_unlock(&idetape_ref_mutex); 2390 2391 idetape_setup(drive, tape, minor); 2392 2393 device_create(idetape_sysfs_class, &drive->gendev, 2394 MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name); 2395 device_create(idetape_sysfs_class, &drive->gendev, 2396 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2397 "n%s", tape->name); 2398 2399 g->fops = &idetape_block_ops; 2400 ide_register_region(g); 2401 2402 return 0; 2403 2404out_free_disk: 2405 put_disk(g); 2406out_free_tape: 2407 kfree(tape); 2408failed: 2409 return -ENODEV; 2410} 2411 2412static void __exit idetape_exit(void) 2413{ 2414 driver_unregister(&idetape_driver.gen_driver); 2415 class_destroy(idetape_sysfs_class); 2416 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2417} 2418 2419static int __init idetape_init(void) 2420{ 2421 int error = 1; 2422 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2423 if (IS_ERR(idetape_sysfs_class)) { 2424 idetape_sysfs_class = NULL; 2425 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2426 error = -EBUSY; 2427 goto out; 2428 } 2429 2430 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2431 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2432 " interface\n"); 2433 error = -EBUSY; 2434 goto out_free_class; 2435 } 2436 2437 error = driver_register(&idetape_driver.gen_driver); 2438 if (error) 2439 goto out_free_driver; 2440 2441 return 0; 2442 2443out_free_driver: 2444 driver_unregister(&idetape_driver.gen_driver); 2445out_free_class: 2446 class_destroy(idetape_sysfs_class); 2447out: 2448 return error; 2449} 2450 2451MODULE_ALIAS("ide:*m-tape*"); 2452module_init(idetape_init); 2453module_exit(idetape_exit); 2454MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2455MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2456MODULE_LICENSE("GPL"); 2457