ide-tape.c revision 3ee38302ffc63da93eb0313053a990bb3466e275
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 void 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 if (uptodate == 0) 534 drive->failed_pc = NULL; 535 536 if (blk_special_request(rq)) 537 ide_complete_rq(drive, 0); 538 else 539 ide_end_request(drive, uptodate, 0); 540} 541 542/* 543 * Postpone the current request so that ide.c will be able to service requests 544 * from another device on the same port while we are polling for DSC. 545 */ 546static void idetape_postpone_request(ide_drive_t *drive) 547{ 548 idetape_tape_t *tape = drive->driver_data; 549 550 debug_log(DBG_PROCS, "Enter %s\n", __func__); 551 552 tape->postponed_rq = drive->hwif->rq; 553 554 ide_stall_queue(drive, tape->dsc_poll_freq); 555} 556 557static void ide_tape_handle_dsc(ide_drive_t *drive) 558{ 559 idetape_tape_t *tape = drive->driver_data; 560 561 /* Media access command */ 562 tape->dsc_polling_start = jiffies; 563 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 564 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 565 /* Allow ide.c to handle other requests */ 566 idetape_postpone_request(drive); 567} 568 569static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 570 unsigned int bcount, int write) 571{ 572 if (write) 573 idetape_output_buffers(drive, pc, bcount); 574 else 575 idetape_input_buffers(drive, pc, bcount); 576 577 return bcount; 578} 579 580/* 581 * Packet Command Interface 582 * 583 * The current Packet Command is available in drive->pc, and will not change 584 * until we finish handling it. Each packet command is associated with a 585 * callback function that will be called when the command is finished. 586 * 587 * The handling will be done in three stages: 588 * 589 * 1. idetape_issue_pc will send the packet command to the drive, and will set 590 * the interrupt handler to ide_pc_intr. 591 * 592 * 2. On each interrupt, ide_pc_intr will be called. This step will be 593 * repeated until the device signals us that no more interrupts will be issued. 594 * 595 * 3. ATAPI Tape media access commands have immediate status with a delayed 596 * process. In case of a successful initiation of a media access packet command, 597 * the DSC bit will be set when the actual execution of the command is finished. 598 * Since the tape drive will not issue an interrupt, we have to poll for this 599 * event. In this case, we define the request as "low priority request" by 600 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 601 * exit the driver. 602 * 603 * ide.c will then give higher priority to requests which originate from the 604 * other device, until will change rq_status to RQ_ACTIVE. 605 * 606 * 4. When the packet command is finished, it will be checked for errors. 607 * 608 * 5. In case an error was found, we queue a request sense packet command in 609 * front of the request queue and retry the operation up to 610 * IDETAPE_MAX_PC_RETRIES times. 611 * 612 * 6. In case no error was found, or we decided to give up and not to retry 613 * again, the callback function will be called and then we will handle the next 614 * request. 615 */ 616 617static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 618 struct ide_atapi_pc *pc) 619{ 620 idetape_tape_t *tape = drive->driver_data; 621 622 if (drive->pc->c[0] == REQUEST_SENSE && 623 pc->c[0] == REQUEST_SENSE) { 624 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 625 "Two request sense in serial were issued\n"); 626 } 627 628 if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 629 drive->failed_pc = pc; 630 631 /* Set the current packet command */ 632 drive->pc = pc; 633 634 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 635 (pc->flags & PC_FLAG_ABORT)) { 636 /* 637 * We will "abort" retrying a packet command in case legitimate 638 * error code was received (crossing a filemark, or end of the 639 * media, for example). 640 */ 641 if (!(pc->flags & PC_FLAG_ABORT)) { 642 if (!(pc->c[0] == TEST_UNIT_READY && 643 tape->sense_key == 2 && tape->asc == 4 && 644 (tape->ascq == 1 || tape->ascq == 8))) { 645 printk(KERN_ERR "ide-tape: %s: I/O error, " 646 "pc = %2x, key = %2x, " 647 "asc = %2x, ascq = %2x\n", 648 tape->name, pc->c[0], 649 tape->sense_key, tape->asc, 650 tape->ascq); 651 } 652 /* Giving up */ 653 pc->error = IDE_DRV_ERROR_GENERAL; 654 } 655 drive->failed_pc = NULL; 656 drive->pc_callback(drive, 0); 657 return ide_stopped; 658 } 659 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 660 661 pc->retries++; 662 663 return ide_issue_pc(drive); 664} 665 666/* A mode sense command is used to "sense" tape parameters. */ 667static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 668{ 669 ide_init_pc(pc); 670 pc->c[0] = MODE_SENSE; 671 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 672 /* DBD = 1 - Don't return block descriptors */ 673 pc->c[1] = 8; 674 pc->c[2] = page_code; 675 /* 676 * Changed pc->c[3] to 0 (255 will at best return unused info). 677 * 678 * For SCSI this byte is defined as subpage instead of high byte 679 * of length and some IDE drives seem to interpret it this way 680 * and return an error when 255 is used. 681 */ 682 pc->c[3] = 0; 683 /* We will just discard data in that case */ 684 pc->c[4] = 255; 685 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 686 pc->req_xfer = 12; 687 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 688 pc->req_xfer = 24; 689 else 690 pc->req_xfer = 50; 691} 692 693static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 694{ 695 ide_hwif_t *hwif = drive->hwif; 696 idetape_tape_t *tape = drive->driver_data; 697 struct ide_atapi_pc *pc = drive->pc; 698 u8 stat; 699 700 stat = hwif->tp_ops->read_status(hwif); 701 702 if (stat & ATA_DSC) { 703 if (stat & ATA_ERR) { 704 /* Error detected */ 705 if (pc->c[0] != TEST_UNIT_READY) 706 printk(KERN_ERR "ide-tape: %s: I/O error, ", 707 tape->name); 708 /* Retry operation */ 709 ide_retry_pc(drive, tape->disk); 710 return ide_stopped; 711 } 712 pc->error = 0; 713 } else { 714 pc->error = IDE_DRV_ERROR_GENERAL; 715 drive->failed_pc = NULL; 716 } 717 drive->pc_callback(drive, 0); 718 return ide_stopped; 719} 720 721static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 722 struct ide_atapi_pc *pc, struct request *rq, 723 u8 opcode) 724{ 725 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 726 unsigned int length = rq->current_nr_sectors; 727 728 ide_init_pc(pc); 729 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 730 pc->c[1] = 1; 731 pc->bh = bh; 732 pc->buf = NULL; 733 pc->buf_size = length * tape->blk_size; 734 pc->req_xfer = pc->buf_size; 735 if (pc->req_xfer == tape->buffer_size) 736 pc->flags |= PC_FLAG_DMA_OK; 737 738 if (opcode == READ_6) { 739 pc->c[0] = READ_6; 740 atomic_set(&bh->b_count, 0); 741 } else if (opcode == WRITE_6) { 742 pc->c[0] = WRITE_6; 743 pc->flags |= PC_FLAG_WRITING; 744 pc->b_data = bh->b_data; 745 pc->b_count = atomic_read(&bh->b_count); 746 } 747 748 memcpy(rq->cmd, pc->c, 12); 749} 750 751static ide_startstop_t idetape_do_request(ide_drive_t *drive, 752 struct request *rq, sector_t block) 753{ 754 ide_hwif_t *hwif = drive->hwif; 755 idetape_tape_t *tape = drive->driver_data; 756 struct ide_atapi_pc *pc = NULL; 757 struct request *postponed_rq = tape->postponed_rq; 758 u8 stat; 759 760 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 761 " current_nr_sectors: %u\n", 762 (unsigned long long)rq->sector, rq->nr_sectors, 763 rq->current_nr_sectors); 764 765 if (!blk_special_request(rq)) { 766 /* We do not support buffer cache originated requests. */ 767 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 768 "request queue (%d)\n", drive->name, rq->cmd_type); 769 ide_end_request(drive, 0, 0); 770 return ide_stopped; 771 } 772 773 /* Retry a failed packet command */ 774 if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { 775 pc = drive->failed_pc; 776 goto out; 777 } 778 779 if (postponed_rq != NULL) 780 if (rq != postponed_rq) { 781 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 782 "Two DSC requests were queued\n"); 783 rq->errors = IDE_DRV_ERROR_GENERAL; 784 drive->failed_pc = NULL; 785 ide_complete_rq(drive, 0); 786 return ide_stopped; 787 } 788 789 tape->postponed_rq = NULL; 790 791 /* 792 * If the tape is still busy, postpone our request and service 793 * the other device meanwhile. 794 */ 795 stat = hwif->tp_ops->read_status(hwif); 796 797 if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 && 798 (rq->cmd[13] & REQ_IDETAPE_PC2) == 0) 799 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 800 801 if (drive->dev_flags & IDE_DFLAG_POST_RESET) { 802 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 803 drive->dev_flags &= ~IDE_DFLAG_POST_RESET; 804 } 805 806 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 807 (stat & ATA_DSC) == 0) { 808 if (postponed_rq == NULL) { 809 tape->dsc_polling_start = jiffies; 810 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 811 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 812 } else if (time_after(jiffies, tape->dsc_timeout)) { 813 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 814 tape->name); 815 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 816 idetape_media_access_finished(drive); 817 return ide_stopped; 818 } else { 819 return ide_do_reset(drive); 820 } 821 } else if (time_after(jiffies, 822 tape->dsc_polling_start + 823 IDETAPE_DSC_MA_THRESHOLD)) 824 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 825 idetape_postpone_request(drive); 826 return ide_stopped; 827 } 828 if (rq->cmd[13] & REQ_IDETAPE_READ) { 829 pc = &tape->queued_pc; 830 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 831 goto out; 832 } 833 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 834 pc = &tape->queued_pc; 835 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 836 goto out; 837 } 838 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 839 pc = (struct ide_atapi_pc *) rq->buffer; 840 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 841 rq->cmd[13] |= REQ_IDETAPE_PC2; 842 goto out; 843 } 844 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 845 idetape_media_access_finished(drive); 846 return ide_stopped; 847 } 848 BUG(); 849 850out: 851 return idetape_issue_pc(drive, pc); 852} 853 854/* 855 * The function below uses __get_free_pages to allocate a data buffer of size 856 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 857 * much as possible. 858 * 859 * It returns a pointer to the newly allocated buffer, or NULL in case of 860 * failure. 861 */ 862static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 863 int full, int clear) 864{ 865 struct idetape_bh *prev_bh, *bh, *merge_bh; 866 int pages = tape->pages_per_buffer; 867 unsigned int order, b_allocd; 868 char *b_data = NULL; 869 870 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 871 bh = merge_bh; 872 if (bh == NULL) 873 goto abort; 874 875 order = fls(pages) - 1; 876 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 877 if (!bh->b_data) 878 goto abort; 879 b_allocd = (1 << order) * PAGE_SIZE; 880 pages &= (order-1); 881 882 if (clear) 883 memset(bh->b_data, 0, b_allocd); 884 bh->b_reqnext = NULL; 885 bh->b_size = b_allocd; 886 atomic_set(&bh->b_count, full ? bh->b_size : 0); 887 888 while (pages) { 889 order = fls(pages) - 1; 890 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 891 if (!b_data) 892 goto abort; 893 b_allocd = (1 << order) * PAGE_SIZE; 894 895 if (clear) 896 memset(b_data, 0, b_allocd); 897 898 /* newly allocated page frames below buffer header or ...*/ 899 if (bh->b_data == b_data + b_allocd) { 900 bh->b_size += b_allocd; 901 bh->b_data -= b_allocd; 902 if (full) 903 atomic_add(b_allocd, &bh->b_count); 904 continue; 905 } 906 /* they are above the header */ 907 if (b_data == bh->b_data + bh->b_size) { 908 bh->b_size += b_allocd; 909 if (full) 910 atomic_add(b_allocd, &bh->b_count); 911 continue; 912 } 913 prev_bh = bh; 914 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 915 if (!bh) { 916 free_pages((unsigned long) b_data, order); 917 goto abort; 918 } 919 bh->b_reqnext = NULL; 920 bh->b_data = b_data; 921 bh->b_size = b_allocd; 922 atomic_set(&bh->b_count, full ? bh->b_size : 0); 923 prev_bh->b_reqnext = bh; 924 925 pages &= (order-1); 926 } 927 928 bh->b_size -= tape->excess_bh_size; 929 if (full) 930 atomic_sub(tape->excess_bh_size, &bh->b_count); 931 return merge_bh; 932abort: 933 ide_tape_kfree_buffer(tape); 934 return NULL; 935} 936 937static int idetape_copy_stage_from_user(idetape_tape_t *tape, 938 const char __user *buf, int n) 939{ 940 struct idetape_bh *bh = tape->bh; 941 int count; 942 int ret = 0; 943 944 while (n) { 945 if (bh == NULL) { 946 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 947 __func__); 948 return 1; 949 } 950 count = min((unsigned int) 951 (bh->b_size - atomic_read(&bh->b_count)), 952 (unsigned int)n); 953 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 954 count)) 955 ret = 1; 956 n -= count; 957 atomic_add(count, &bh->b_count); 958 buf += count; 959 if (atomic_read(&bh->b_count) == bh->b_size) { 960 bh = bh->b_reqnext; 961 if (bh) 962 atomic_set(&bh->b_count, 0); 963 } 964 } 965 tape->bh = bh; 966 return ret; 967} 968 969static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 970 int n) 971{ 972 struct idetape_bh *bh = tape->bh; 973 int count; 974 int ret = 0; 975 976 while (n) { 977 if (bh == NULL) { 978 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 979 __func__); 980 return 1; 981 } 982 count = min(tape->b_count, n); 983 if (copy_to_user(buf, tape->b_data, count)) 984 ret = 1; 985 n -= count; 986 tape->b_data += count; 987 tape->b_count -= count; 988 buf += count; 989 if (!tape->b_count) { 990 bh = bh->b_reqnext; 991 tape->bh = bh; 992 if (bh) { 993 tape->b_data = bh->b_data; 994 tape->b_count = atomic_read(&bh->b_count); 995 } 996 } 997 } 998 return ret; 999} 1000 1001static void idetape_init_merge_buffer(idetape_tape_t *tape) 1002{ 1003 struct idetape_bh *bh = tape->merge_bh; 1004 tape->bh = tape->merge_bh; 1005 1006 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1007 atomic_set(&bh->b_count, 0); 1008 else { 1009 tape->b_data = bh->b_data; 1010 tape->b_count = atomic_read(&bh->b_count); 1011 } 1012} 1013 1014/* 1015 * Write a filemark if write_filemark=1. Flush the device buffers without 1016 * writing a filemark otherwise. 1017 */ 1018static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1019 struct ide_atapi_pc *pc, int write_filemark) 1020{ 1021 ide_init_pc(pc); 1022 pc->c[0] = WRITE_FILEMARKS; 1023 pc->c[4] = write_filemark; 1024 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1025} 1026 1027static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1028{ 1029 idetape_tape_t *tape = drive->driver_data; 1030 struct gendisk *disk = tape->disk; 1031 int load_attempted = 0; 1032 1033 /* Wait for the tape to become ready */ 1034 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1035 timeout += jiffies; 1036 while (time_before(jiffies, timeout)) { 1037 if (ide_do_test_unit_ready(drive, disk) == 0) 1038 return 0; 1039 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1040 || (tape->asc == 0x3A)) { 1041 /* no media */ 1042 if (load_attempted) 1043 return -ENOMEDIUM; 1044 ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1045 load_attempted = 1; 1046 /* not about to be ready */ 1047 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1048 (tape->ascq == 1 || tape->ascq == 8))) 1049 return -EIO; 1050 msleep(100); 1051 } 1052 return -EIO; 1053} 1054 1055static int idetape_flush_tape_buffers(ide_drive_t *drive) 1056{ 1057 struct ide_tape_obj *tape = drive->driver_data; 1058 struct ide_atapi_pc pc; 1059 int rc; 1060 1061 idetape_create_write_filemark_cmd(drive, &pc, 0); 1062 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1063 if (rc) 1064 return rc; 1065 idetape_wait_ready(drive, 60 * 5 * HZ); 1066 return 0; 1067} 1068 1069static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1070{ 1071 ide_init_pc(pc); 1072 pc->c[0] = READ_POSITION; 1073 pc->req_xfer = 20; 1074} 1075 1076static int idetape_read_position(ide_drive_t *drive) 1077{ 1078 idetape_tape_t *tape = drive->driver_data; 1079 struct ide_atapi_pc pc; 1080 int position; 1081 1082 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1083 1084 idetape_create_read_position_cmd(&pc); 1085 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1086 return -1; 1087 position = tape->first_frame; 1088 return position; 1089} 1090 1091static void idetape_create_locate_cmd(ide_drive_t *drive, 1092 struct ide_atapi_pc *pc, 1093 unsigned int block, u8 partition, int skip) 1094{ 1095 ide_init_pc(pc); 1096 pc->c[0] = POSITION_TO_ELEMENT; 1097 pc->c[1] = 2; 1098 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1099 pc->c[8] = partition; 1100 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1101} 1102 1103static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1104{ 1105 idetape_tape_t *tape = drive->driver_data; 1106 1107 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1108 return; 1109 1110 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1111 tape->merge_bh_size = 0; 1112 if (tape->merge_bh != NULL) { 1113 ide_tape_kfree_buffer(tape); 1114 tape->merge_bh = NULL; 1115 } 1116 1117 tape->chrdev_dir = IDETAPE_DIR_NONE; 1118} 1119 1120/* 1121 * Position the tape to the requested block using the LOCATE packet command. 1122 * A READ POSITION command is then issued to check where we are positioned. Like 1123 * all higher level operations, we queue the commands at the tail of the request 1124 * queue and wait for their completion. 1125 */ 1126static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1127 u8 partition, int skip) 1128{ 1129 idetape_tape_t *tape = drive->driver_data; 1130 struct gendisk *disk = tape->disk; 1131 int retval; 1132 struct ide_atapi_pc pc; 1133 1134 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1135 __ide_tape_discard_merge_buffer(drive); 1136 idetape_wait_ready(drive, 60 * 5 * HZ); 1137 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1138 retval = ide_queue_pc_tail(drive, disk, &pc); 1139 if (retval) 1140 return (retval); 1141 1142 idetape_create_read_position_cmd(&pc); 1143 return ide_queue_pc_tail(drive, disk, &pc); 1144} 1145 1146static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1147 int restore_position) 1148{ 1149 idetape_tape_t *tape = drive->driver_data; 1150 int seek, position; 1151 1152 __ide_tape_discard_merge_buffer(drive); 1153 if (restore_position) { 1154 position = idetape_read_position(drive); 1155 seek = position > 0 ? position : 0; 1156 if (idetape_position_tape(drive, seek, 0, 0)) { 1157 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1158 " %s\n", tape->name, __func__); 1159 return; 1160 } 1161 } 1162} 1163 1164/* 1165 * Generate a read/write request for the block device interface and wait for it 1166 * to be serviced. 1167 */ 1168static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1169 struct idetape_bh *bh) 1170{ 1171 idetape_tape_t *tape = drive->driver_data; 1172 struct request *rq; 1173 int ret, errors; 1174 1175 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1176 1177 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1178 rq->cmd_type = REQ_TYPE_SPECIAL; 1179 rq->cmd[13] = cmd; 1180 rq->rq_disk = tape->disk; 1181 rq->special = (void *)bh; 1182 rq->sector = tape->first_frame; 1183 rq->nr_sectors = blocks; 1184 rq->current_nr_sectors = blocks; 1185 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1186 1187 errors = rq->errors; 1188 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1189 blk_put_request(rq); 1190 1191 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1192 return 0; 1193 1194 if (tape->merge_bh) 1195 idetape_init_merge_buffer(tape); 1196 if (errors == IDE_DRV_ERROR_GENERAL) 1197 return -EIO; 1198 return ret; 1199} 1200 1201static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1202{ 1203 ide_init_pc(pc); 1204 pc->c[0] = INQUIRY; 1205 pc->c[4] = 254; 1206 pc->req_xfer = 254; 1207} 1208 1209static void idetape_create_rewind_cmd(ide_drive_t *drive, 1210 struct ide_atapi_pc *pc) 1211{ 1212 ide_init_pc(pc); 1213 pc->c[0] = REZERO_UNIT; 1214 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1215} 1216 1217static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1218{ 1219 ide_init_pc(pc); 1220 pc->c[0] = ERASE; 1221 pc->c[1] = 1; 1222 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1223} 1224 1225static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1226{ 1227 ide_init_pc(pc); 1228 pc->c[0] = SPACE; 1229 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1230 pc->c[1] = cmd; 1231 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1232} 1233 1234/* Queue up a character device originated write request. */ 1235static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1236{ 1237 idetape_tape_t *tape = drive->driver_data; 1238 1239 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1240 1241 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1242 blocks, tape->merge_bh); 1243} 1244 1245static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1246{ 1247 idetape_tape_t *tape = drive->driver_data; 1248 int blocks, min; 1249 struct idetape_bh *bh; 1250 1251 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1252 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1253 " but we are not writing.\n"); 1254 return; 1255 } 1256 if (tape->merge_bh_size > tape->buffer_size) { 1257 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1258 tape->merge_bh_size = tape->buffer_size; 1259 } 1260 if (tape->merge_bh_size) { 1261 blocks = tape->merge_bh_size / tape->blk_size; 1262 if (tape->merge_bh_size % tape->blk_size) { 1263 unsigned int i; 1264 1265 blocks++; 1266 i = tape->blk_size - tape->merge_bh_size % 1267 tape->blk_size; 1268 bh = tape->bh->b_reqnext; 1269 while (bh) { 1270 atomic_set(&bh->b_count, 0); 1271 bh = bh->b_reqnext; 1272 } 1273 bh = tape->bh; 1274 while (i) { 1275 if (bh == NULL) { 1276 printk(KERN_INFO "ide-tape: bug," 1277 " bh NULL\n"); 1278 break; 1279 } 1280 min = min(i, (unsigned int)(bh->b_size - 1281 atomic_read(&bh->b_count))); 1282 memset(bh->b_data + atomic_read(&bh->b_count), 1283 0, min); 1284 atomic_add(min, &bh->b_count); 1285 i -= min; 1286 bh = bh->b_reqnext; 1287 } 1288 } 1289 (void) idetape_add_chrdev_write_request(drive, blocks); 1290 tape->merge_bh_size = 0; 1291 } 1292 if (tape->merge_bh != NULL) { 1293 ide_tape_kfree_buffer(tape); 1294 tape->merge_bh = NULL; 1295 } 1296 tape->chrdev_dir = IDETAPE_DIR_NONE; 1297} 1298 1299static int idetape_init_read(ide_drive_t *drive) 1300{ 1301 idetape_tape_t *tape = drive->driver_data; 1302 int bytes_read; 1303 1304 /* Initialize read operation */ 1305 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1306 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1307 ide_tape_flush_merge_buffer(drive); 1308 idetape_flush_tape_buffers(drive); 1309 } 1310 if (tape->merge_bh || tape->merge_bh_size) { 1311 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1312 " 0 now\n"); 1313 tape->merge_bh_size = 0; 1314 } 1315 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1316 if (!tape->merge_bh) 1317 return -ENOMEM; 1318 tape->chrdev_dir = IDETAPE_DIR_READ; 1319 1320 /* 1321 * Issue a read 0 command to ensure that DSC handshake is 1322 * switched from completion mode to buffer available mode. 1323 * No point in issuing this if DSC overlap isn't supported, some 1324 * drives (Seagate STT3401A) will return an error. 1325 */ 1326 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1327 bytes_read = idetape_queue_rw_tail(drive, 1328 REQ_IDETAPE_READ, 0, 1329 tape->merge_bh); 1330 if (bytes_read < 0) { 1331 ide_tape_kfree_buffer(tape); 1332 tape->merge_bh = NULL; 1333 tape->chrdev_dir = IDETAPE_DIR_NONE; 1334 return bytes_read; 1335 } 1336 } 1337 } 1338 1339 return 0; 1340} 1341 1342/* called from idetape_chrdev_read() to service a chrdev read request. */ 1343static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1344{ 1345 idetape_tape_t *tape = drive->driver_data; 1346 1347 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1348 1349 /* If we are at a filemark, return a read length of 0 */ 1350 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1351 return 0; 1352 1353 idetape_init_read(drive); 1354 1355 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1356 tape->merge_bh); 1357} 1358 1359static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1360{ 1361 idetape_tape_t *tape = drive->driver_data; 1362 struct idetape_bh *bh; 1363 int blocks; 1364 1365 while (bcount) { 1366 unsigned int count; 1367 1368 bh = tape->merge_bh; 1369 count = min(tape->buffer_size, bcount); 1370 bcount -= count; 1371 blocks = count / tape->blk_size; 1372 while (count) { 1373 atomic_set(&bh->b_count, 1374 min(count, (unsigned int)bh->b_size)); 1375 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1376 count -= atomic_read(&bh->b_count); 1377 bh = bh->b_reqnext; 1378 } 1379 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1380 tape->merge_bh); 1381 } 1382} 1383 1384/* 1385 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1386 * currently support only one partition. 1387 */ 1388static int idetape_rewind_tape(ide_drive_t *drive) 1389{ 1390 struct ide_tape_obj *tape = drive->driver_data; 1391 struct gendisk *disk = tape->disk; 1392 int retval; 1393 struct ide_atapi_pc pc; 1394 1395 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1396 1397 idetape_create_rewind_cmd(drive, &pc); 1398 retval = ide_queue_pc_tail(drive, disk, &pc); 1399 if (retval) 1400 return retval; 1401 1402 idetape_create_read_position_cmd(&pc); 1403 retval = ide_queue_pc_tail(drive, disk, &pc); 1404 if (retval) 1405 return retval; 1406 return 0; 1407} 1408 1409/* mtio.h compatible commands should be issued to the chrdev interface. */ 1410static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1411 unsigned long arg) 1412{ 1413 idetape_tape_t *tape = drive->driver_data; 1414 void __user *argp = (void __user *)arg; 1415 1416 struct idetape_config { 1417 int dsc_rw_frequency; 1418 int dsc_media_access_frequency; 1419 int nr_stages; 1420 } config; 1421 1422 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1423 1424 switch (cmd) { 1425 case 0x0340: 1426 if (copy_from_user(&config, argp, sizeof(config))) 1427 return -EFAULT; 1428 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1429 break; 1430 case 0x0350: 1431 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1432 config.nr_stages = 1; 1433 if (copy_to_user(argp, &config, sizeof(config))) 1434 return -EFAULT; 1435 break; 1436 default: 1437 return -EIO; 1438 } 1439 return 0; 1440} 1441 1442static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1443 int mt_count) 1444{ 1445 idetape_tape_t *tape = drive->driver_data; 1446 struct gendisk *disk = tape->disk; 1447 struct ide_atapi_pc pc; 1448 int retval, count = 0; 1449 int sprev = !!(tape->caps[4] & 0x20); 1450 1451 if (mt_count == 0) 1452 return 0; 1453 if (MTBSF == mt_op || MTBSFM == mt_op) { 1454 if (!sprev) 1455 return -EIO; 1456 mt_count = -mt_count; 1457 } 1458 1459 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1460 tape->merge_bh_size = 0; 1461 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1462 ++count; 1463 ide_tape_discard_merge_buffer(drive, 0); 1464 } 1465 1466 switch (mt_op) { 1467 case MTFSF: 1468 case MTBSF: 1469 idetape_create_space_cmd(&pc, mt_count - count, 1470 IDETAPE_SPACE_OVER_FILEMARK); 1471 return ide_queue_pc_tail(drive, disk, &pc); 1472 case MTFSFM: 1473 case MTBSFM: 1474 if (!sprev) 1475 return -EIO; 1476 retval = idetape_space_over_filemarks(drive, MTFSF, 1477 mt_count - count); 1478 if (retval) 1479 return retval; 1480 count = (MTBSFM == mt_op ? 1 : -1); 1481 return idetape_space_over_filemarks(drive, MTFSF, count); 1482 default: 1483 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1484 mt_op); 1485 return -EIO; 1486 } 1487} 1488 1489/* 1490 * Our character device read / write functions. 1491 * 1492 * The tape is optimized to maximize throughput when it is transferring an 1493 * integral number of the "continuous transfer limit", which is a parameter of 1494 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1495 * 1496 * As of version 1.3 of the driver, the character device provides an abstract 1497 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1498 * same backup/restore procedure is supported. The driver will internally 1499 * convert the requests to the recommended transfer unit, so that an unmatch 1500 * between the user's block size to the recommended size will only result in a 1501 * (slightly) increased driver overhead, but will no longer hit performance. 1502 * This is not applicable to Onstream. 1503 */ 1504static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1505 size_t count, loff_t *ppos) 1506{ 1507 struct ide_tape_obj *tape = file->private_data; 1508 ide_drive_t *drive = tape->drive; 1509 ssize_t bytes_read, temp, actually_read = 0, rc; 1510 ssize_t ret = 0; 1511 u16 ctl = *(u16 *)&tape->caps[12]; 1512 1513 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1514 1515 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1516 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1517 if (count > tape->blk_size && 1518 (count % tape->blk_size) == 0) 1519 tape->user_bs_factor = count / tape->blk_size; 1520 } 1521 rc = idetape_init_read(drive); 1522 if (rc < 0) 1523 return rc; 1524 if (count == 0) 1525 return (0); 1526 if (tape->merge_bh_size) { 1527 actually_read = min((unsigned int)(tape->merge_bh_size), 1528 (unsigned int)count); 1529 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1530 ret = -EFAULT; 1531 buf += actually_read; 1532 tape->merge_bh_size -= actually_read; 1533 count -= actually_read; 1534 } 1535 while (count >= tape->buffer_size) { 1536 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1537 if (bytes_read <= 0) 1538 goto finish; 1539 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1540 ret = -EFAULT; 1541 buf += bytes_read; 1542 count -= bytes_read; 1543 actually_read += bytes_read; 1544 } 1545 if (count) { 1546 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1547 if (bytes_read <= 0) 1548 goto finish; 1549 temp = min((unsigned long)count, (unsigned long)bytes_read); 1550 if (idetape_copy_stage_to_user(tape, buf, temp)) 1551 ret = -EFAULT; 1552 actually_read += temp; 1553 tape->merge_bh_size = bytes_read-temp; 1554 } 1555finish: 1556 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1557 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1558 1559 idetape_space_over_filemarks(drive, MTFSF, 1); 1560 return 0; 1561 } 1562 1563 return ret ? ret : actually_read; 1564} 1565 1566static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1567 size_t count, loff_t *ppos) 1568{ 1569 struct ide_tape_obj *tape = file->private_data; 1570 ide_drive_t *drive = tape->drive; 1571 ssize_t actually_written = 0; 1572 ssize_t ret = 0; 1573 u16 ctl = *(u16 *)&tape->caps[12]; 1574 1575 /* The drive is write protected. */ 1576 if (tape->write_prot) 1577 return -EACCES; 1578 1579 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1580 1581 /* Initialize write operation */ 1582 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1583 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1584 ide_tape_discard_merge_buffer(drive, 1); 1585 if (tape->merge_bh || tape->merge_bh_size) { 1586 printk(KERN_ERR "ide-tape: merge_bh_size " 1587 "should be 0 now\n"); 1588 tape->merge_bh_size = 0; 1589 } 1590 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1591 if (!tape->merge_bh) 1592 return -ENOMEM; 1593 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1594 idetape_init_merge_buffer(tape); 1595 1596 /* 1597 * Issue a write 0 command to ensure that DSC handshake is 1598 * switched from completion mode to buffer available mode. No 1599 * point in issuing this if DSC overlap isn't supported, some 1600 * drives (Seagate STT3401A) will return an error. 1601 */ 1602 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1603 ssize_t retval = idetape_queue_rw_tail(drive, 1604 REQ_IDETAPE_WRITE, 0, 1605 tape->merge_bh); 1606 if (retval < 0) { 1607 ide_tape_kfree_buffer(tape); 1608 tape->merge_bh = NULL; 1609 tape->chrdev_dir = IDETAPE_DIR_NONE; 1610 return retval; 1611 } 1612 } 1613 } 1614 if (count == 0) 1615 return (0); 1616 if (tape->merge_bh_size) { 1617 if (tape->merge_bh_size >= tape->buffer_size) { 1618 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1619 tape->merge_bh_size = 0; 1620 } 1621 actually_written = min((unsigned int) 1622 (tape->buffer_size - tape->merge_bh_size), 1623 (unsigned int)count); 1624 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1625 ret = -EFAULT; 1626 buf += actually_written; 1627 tape->merge_bh_size += actually_written; 1628 count -= actually_written; 1629 1630 if (tape->merge_bh_size == tape->buffer_size) { 1631 ssize_t retval; 1632 tape->merge_bh_size = 0; 1633 retval = idetape_add_chrdev_write_request(drive, ctl); 1634 if (retval <= 0) 1635 return (retval); 1636 } 1637 } 1638 while (count >= tape->buffer_size) { 1639 ssize_t retval; 1640 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1641 ret = -EFAULT; 1642 buf += tape->buffer_size; 1643 count -= tape->buffer_size; 1644 retval = idetape_add_chrdev_write_request(drive, ctl); 1645 actually_written += tape->buffer_size; 1646 if (retval <= 0) 1647 return (retval); 1648 } 1649 if (count) { 1650 actually_written += count; 1651 if (idetape_copy_stage_from_user(tape, buf, count)) 1652 ret = -EFAULT; 1653 tape->merge_bh_size += count; 1654 } 1655 return ret ? ret : actually_written; 1656} 1657 1658static int idetape_write_filemark(ide_drive_t *drive) 1659{ 1660 struct ide_tape_obj *tape = drive->driver_data; 1661 struct ide_atapi_pc pc; 1662 1663 /* Write a filemark */ 1664 idetape_create_write_filemark_cmd(drive, &pc, 1); 1665 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1666 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1667 return -EIO; 1668 } 1669 return 0; 1670} 1671 1672/* 1673 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1674 * requested. 1675 * 1676 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1677 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1678 * usually not supported. 1679 * 1680 * The following commands are currently not supported: 1681 * 1682 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1683 * MT_ST_WRITE_THRESHOLD. 1684 */ 1685static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1686{ 1687 idetape_tape_t *tape = drive->driver_data; 1688 struct gendisk *disk = tape->disk; 1689 struct ide_atapi_pc pc; 1690 int i, retval; 1691 1692 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1693 mt_op, mt_count); 1694 1695 switch (mt_op) { 1696 case MTFSF: 1697 case MTFSFM: 1698 case MTBSF: 1699 case MTBSFM: 1700 if (!mt_count) 1701 return 0; 1702 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1703 default: 1704 break; 1705 } 1706 1707 switch (mt_op) { 1708 case MTWEOF: 1709 if (tape->write_prot) 1710 return -EACCES; 1711 ide_tape_discard_merge_buffer(drive, 1); 1712 for (i = 0; i < mt_count; i++) { 1713 retval = idetape_write_filemark(drive); 1714 if (retval) 1715 return retval; 1716 } 1717 return 0; 1718 case MTREW: 1719 ide_tape_discard_merge_buffer(drive, 0); 1720 if (idetape_rewind_tape(drive)) 1721 return -EIO; 1722 return 0; 1723 case MTLOAD: 1724 ide_tape_discard_merge_buffer(drive, 0); 1725 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1726 case MTUNLOAD: 1727 case MTOFFL: 1728 /* 1729 * If door is locked, attempt to unlock before 1730 * attempting to eject. 1731 */ 1732 if (tape->door_locked) { 1733 if (!ide_set_media_lock(drive, disk, 0)) 1734 tape->door_locked = DOOR_UNLOCKED; 1735 } 1736 ide_tape_discard_merge_buffer(drive, 0); 1737 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); 1738 if (!retval) 1739 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1740 return retval; 1741 case MTNOP: 1742 ide_tape_discard_merge_buffer(drive, 0); 1743 return idetape_flush_tape_buffers(drive); 1744 case MTRETEN: 1745 ide_tape_discard_merge_buffer(drive, 0); 1746 return ide_do_start_stop(drive, disk, 1747 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1748 case MTEOM: 1749 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1750 return ide_queue_pc_tail(drive, disk, &pc); 1751 case MTERASE: 1752 (void)idetape_rewind_tape(drive); 1753 idetape_create_erase_cmd(&pc); 1754 return ide_queue_pc_tail(drive, disk, &pc); 1755 case MTSETBLK: 1756 if (mt_count) { 1757 if (mt_count < tape->blk_size || 1758 mt_count % tape->blk_size) 1759 return -EIO; 1760 tape->user_bs_factor = mt_count / tape->blk_size; 1761 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1762 } else 1763 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1764 return 0; 1765 case MTSEEK: 1766 ide_tape_discard_merge_buffer(drive, 0); 1767 return idetape_position_tape(drive, 1768 mt_count * tape->user_bs_factor, tape->partition, 0); 1769 case MTSETPART: 1770 ide_tape_discard_merge_buffer(drive, 0); 1771 return idetape_position_tape(drive, 0, mt_count, 0); 1772 case MTFSR: 1773 case MTBSR: 1774 case MTLOCK: 1775 retval = ide_set_media_lock(drive, disk, 1); 1776 if (retval) 1777 return retval; 1778 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1779 return 0; 1780 case MTUNLOCK: 1781 retval = ide_set_media_lock(drive, disk, 0); 1782 if (retval) 1783 return retval; 1784 tape->door_locked = DOOR_UNLOCKED; 1785 return 0; 1786 default: 1787 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1788 mt_op); 1789 return -EIO; 1790 } 1791} 1792 1793/* 1794 * Our character device ioctls. General mtio.h magnetic io commands are 1795 * supported here, and not in the corresponding block interface. Our own 1796 * ide-tape ioctls are supported on both interfaces. 1797 */ 1798static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1799 unsigned int cmd, unsigned long arg) 1800{ 1801 struct ide_tape_obj *tape = file->private_data; 1802 ide_drive_t *drive = tape->drive; 1803 struct mtop mtop; 1804 struct mtget mtget; 1805 struct mtpos mtpos; 1806 int block_offset = 0, position = tape->first_frame; 1807 void __user *argp = (void __user *)arg; 1808 1809 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1810 1811 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1812 ide_tape_flush_merge_buffer(drive); 1813 idetape_flush_tape_buffers(drive); 1814 } 1815 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1816 block_offset = tape->merge_bh_size / 1817 (tape->blk_size * tape->user_bs_factor); 1818 position = idetape_read_position(drive); 1819 if (position < 0) 1820 return -EIO; 1821 } 1822 switch (cmd) { 1823 case MTIOCTOP: 1824 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1825 return -EFAULT; 1826 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1827 case MTIOCGET: 1828 memset(&mtget, 0, sizeof(struct mtget)); 1829 mtget.mt_type = MT_ISSCSI2; 1830 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1831 mtget.mt_dsreg = 1832 ((tape->blk_size * tape->user_bs_factor) 1833 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1834 1835 if (tape->drv_write_prot) 1836 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1837 1838 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1839 return -EFAULT; 1840 return 0; 1841 case MTIOCPOS: 1842 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1843 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1844 return -EFAULT; 1845 return 0; 1846 default: 1847 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1848 ide_tape_discard_merge_buffer(drive, 1); 1849 return idetape_blkdev_ioctl(drive, cmd, arg); 1850 } 1851} 1852 1853/* 1854 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1855 * block size with the reported value. 1856 */ 1857static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1858{ 1859 idetape_tape_t *tape = drive->driver_data; 1860 struct ide_atapi_pc pc; 1861 1862 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1863 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1864 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1865 if (tape->blk_size == 0) { 1866 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1867 "block size, assuming 32k\n"); 1868 tape->blk_size = 32768; 1869 } 1870 return; 1871 } 1872 tape->blk_size = (pc.buf[4 + 5] << 16) + 1873 (pc.buf[4 + 6] << 8) + 1874 pc.buf[4 + 7]; 1875 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1876} 1877 1878static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1879{ 1880 unsigned int minor = iminor(inode), i = minor & ~0xc0; 1881 ide_drive_t *drive; 1882 idetape_tape_t *tape; 1883 int retval; 1884 1885 if (i >= MAX_HWIFS * MAX_DRIVES) 1886 return -ENXIO; 1887 1888 lock_kernel(); 1889 tape = ide_tape_chrdev_get(i); 1890 if (!tape) { 1891 unlock_kernel(); 1892 return -ENXIO; 1893 } 1894 1895 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1896 1897 /* 1898 * We really want to do nonseekable_open(inode, filp); here, but some 1899 * versions of tar incorrectly call lseek on tapes and bail out if that 1900 * fails. So we disallow pread() and pwrite(), but permit lseeks. 1901 */ 1902 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 1903 1904 drive = tape->drive; 1905 1906 filp->private_data = tape; 1907 1908 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 1909 retval = -EBUSY; 1910 goto out_put_tape; 1911 } 1912 1913 retval = idetape_wait_ready(drive, 60 * HZ); 1914 if (retval) { 1915 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1916 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 1917 goto out_put_tape; 1918 } 1919 1920 idetape_read_position(drive); 1921 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 1922 (void)idetape_rewind_tape(drive); 1923 1924 /* Read block size and write protect status from drive. */ 1925 ide_tape_get_bsize_from_bdesc(drive); 1926 1927 /* Set write protect flag if device is opened as read-only. */ 1928 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 1929 tape->write_prot = 1; 1930 else 1931 tape->write_prot = tape->drv_write_prot; 1932 1933 /* Make sure drive isn't write protected if user wants to write. */ 1934 if (tape->write_prot) { 1935 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 1936 (filp->f_flags & O_ACCMODE) == O_RDWR) { 1937 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1938 retval = -EROFS; 1939 goto out_put_tape; 1940 } 1941 } 1942 1943 /* Lock the tape drive door so user can't eject. */ 1944 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1945 if (!ide_set_media_lock(drive, tape->disk, 1)) { 1946 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 1947 tape->door_locked = DOOR_LOCKED; 1948 } 1949 } 1950 unlock_kernel(); 1951 return 0; 1952 1953out_put_tape: 1954 ide_tape_put(tape); 1955 unlock_kernel(); 1956 return retval; 1957} 1958 1959static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 1960{ 1961 idetape_tape_t *tape = drive->driver_data; 1962 1963 ide_tape_flush_merge_buffer(drive); 1964 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 1965 if (tape->merge_bh != NULL) { 1966 idetape_pad_zeros(drive, tape->blk_size * 1967 (tape->user_bs_factor - 1)); 1968 ide_tape_kfree_buffer(tape); 1969 tape->merge_bh = NULL; 1970 } 1971 idetape_write_filemark(drive); 1972 idetape_flush_tape_buffers(drive); 1973 idetape_flush_tape_buffers(drive); 1974} 1975 1976static int idetape_chrdev_release(struct inode *inode, struct file *filp) 1977{ 1978 struct ide_tape_obj *tape = filp->private_data; 1979 ide_drive_t *drive = tape->drive; 1980 unsigned int minor = iminor(inode); 1981 1982 lock_kernel(); 1983 tape = drive->driver_data; 1984 1985 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1986 1987 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1988 idetape_write_release(drive, minor); 1989 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1990 if (minor < 128) 1991 ide_tape_discard_merge_buffer(drive, 1); 1992 } 1993 1994 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 1995 (void) idetape_rewind_tape(drive); 1996 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1997 if (tape->door_locked == DOOR_LOCKED) { 1998 if (!ide_set_media_lock(drive, tape->disk, 0)) 1999 tape->door_locked = DOOR_UNLOCKED; 2000 } 2001 } 2002 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2003 ide_tape_put(tape); 2004 unlock_kernel(); 2005 return 0; 2006} 2007 2008static void idetape_get_inquiry_results(ide_drive_t *drive) 2009{ 2010 idetape_tape_t *tape = drive->driver_data; 2011 struct ide_atapi_pc pc; 2012 char fw_rev[4], vendor_id[8], product_id[16]; 2013 2014 idetape_create_inquiry_cmd(&pc); 2015 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2016 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2017 tape->name); 2018 return; 2019 } 2020 memcpy(vendor_id, &pc.buf[8], 8); 2021 memcpy(product_id, &pc.buf[16], 16); 2022 memcpy(fw_rev, &pc.buf[32], 4); 2023 2024 ide_fixstring(vendor_id, 8, 0); 2025 ide_fixstring(product_id, 16, 0); 2026 ide_fixstring(fw_rev, 4, 0); 2027 2028 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2029 drive->name, tape->name, vendor_id, product_id, fw_rev); 2030} 2031 2032/* 2033 * Ask the tape about its various parameters. In particular, we will adjust our 2034 * data transfer buffer size to the recommended value as returned by the tape. 2035 */ 2036static void idetape_get_mode_sense_results(ide_drive_t *drive) 2037{ 2038 idetape_tape_t *tape = drive->driver_data; 2039 struct ide_atapi_pc pc; 2040 u8 *caps; 2041 u8 speed, max_speed; 2042 2043 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2044 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2045 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2046 " some default values\n"); 2047 tape->blk_size = 512; 2048 put_unaligned(52, (u16 *)&tape->caps[12]); 2049 put_unaligned(540, (u16 *)&tape->caps[14]); 2050 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2051 return; 2052 } 2053 caps = pc.buf + 4 + pc.buf[3]; 2054 2055 /* convert to host order and save for later use */ 2056 speed = be16_to_cpup((__be16 *)&caps[14]); 2057 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2058 2059 *(u16 *)&caps[8] = max_speed; 2060 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2061 *(u16 *)&caps[14] = speed; 2062 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2063 2064 if (!speed) { 2065 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2066 "(assuming 650KB/sec)\n", drive->name); 2067 *(u16 *)&caps[14] = 650; 2068 } 2069 if (!max_speed) { 2070 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2071 "(assuming 650KB/sec)\n", drive->name); 2072 *(u16 *)&caps[8] = 650; 2073 } 2074 2075 memcpy(&tape->caps, caps, 20); 2076 2077 /* device lacks locking support according to capabilities page */ 2078 if ((caps[6] & 1) == 0) 2079 drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING; 2080 2081 if (caps[7] & 0x02) 2082 tape->blk_size = 512; 2083 else if (caps[7] & 0x04) 2084 tape->blk_size = 1024; 2085} 2086 2087#ifdef CONFIG_IDE_PROC_FS 2088#define ide_tape_devset_get(name, field) \ 2089static int get_##name(ide_drive_t *drive) \ 2090{ \ 2091 idetape_tape_t *tape = drive->driver_data; \ 2092 return tape->field; \ 2093} 2094 2095#define ide_tape_devset_set(name, field) \ 2096static int set_##name(ide_drive_t *drive, int arg) \ 2097{ \ 2098 idetape_tape_t *tape = drive->driver_data; \ 2099 tape->field = arg; \ 2100 return 0; \ 2101} 2102 2103#define ide_tape_devset_rw_field(_name, _field) \ 2104ide_tape_devset_get(_name, _field) \ 2105ide_tape_devset_set(_name, _field) \ 2106IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name) 2107 2108#define ide_tape_devset_r_field(_name, _field) \ 2109ide_tape_devset_get(_name, _field) \ 2110IDE_DEVSET(_name, 0, get_##_name, NULL) 2111 2112static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2113static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2114static int divf_buffer(ide_drive_t *drive) { return 2; } 2115static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2116 2117ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP); 2118 2119ide_tape_devset_rw_field(debug_mask, debug_mask); 2120ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq); 2121 2122ide_tape_devset_r_field(avg_speed, avg_speed); 2123ide_tape_devset_r_field(speed, caps[14]); 2124ide_tape_devset_r_field(buffer, caps[16]); 2125ide_tape_devset_r_field(buffer_size, buffer_size); 2126 2127static const struct ide_proc_devset idetape_settings[] = { 2128 __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), 2129 __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), 2130 __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), 2131 __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), 2132 __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), 2133 __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), 2134 __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2135 mulf_tdsc, divf_tdsc), 2136 { NULL }, 2137}; 2138#endif 2139 2140/* 2141 * The function below is called to: 2142 * 2143 * 1. Initialize our various state variables. 2144 * 2. Ask the tape for its capabilities. 2145 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2146 * is chosen based on the recommendation which we received in step 2. 2147 * 2148 * Note that at this point ide.c already assigned us an irq, so that we can 2149 * queue requests here and wait for their completion. 2150 */ 2151static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2152{ 2153 unsigned long t; 2154 int speed; 2155 int buffer_size; 2156 u16 *ctl = (u16 *)&tape->caps[12]; 2157 2158 drive->pc_callback = ide_tape_callback; 2159 drive->pc_update_buffers = idetape_update_buffers; 2160 drive->pc_io_buffers = ide_tape_io_buffers; 2161 2162 drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP; 2163 2164 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2165 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2166 tape->name); 2167 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2168 } 2169 2170 /* Seagate Travan drives do not support DSC overlap. */ 2171 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2172 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2173 2174 tape->minor = minor; 2175 tape->name[0] = 'h'; 2176 tape->name[1] = 't'; 2177 tape->name[2] = '0' + minor; 2178 tape->chrdev_dir = IDETAPE_DIR_NONE; 2179 2180 idetape_get_inquiry_results(drive); 2181 idetape_get_mode_sense_results(drive); 2182 ide_tape_get_bsize_from_bdesc(drive); 2183 tape->user_bs_factor = 1; 2184 tape->buffer_size = *ctl * tape->blk_size; 2185 while (tape->buffer_size > 0xffff) { 2186 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2187 *ctl /= 2; 2188 tape->buffer_size = *ctl * tape->blk_size; 2189 } 2190 buffer_size = tape->buffer_size; 2191 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2192 if (buffer_size % PAGE_SIZE) { 2193 tape->pages_per_buffer++; 2194 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2195 } 2196 2197 /* select the "best" DSC read/write polling freq */ 2198 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2199 2200 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2201 2202 /* 2203 * Ensure that the number we got makes sense; limit it within 2204 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2205 */ 2206 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2207 IDETAPE_DSC_RW_MAX); 2208 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2209 "%lums tDSC%s\n", 2210 drive->name, tape->name, *(u16 *)&tape->caps[14], 2211 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2212 tape->buffer_size / 1024, 2213 tape->best_dsc_rw_freq * 1000 / HZ, 2214 (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : ""); 2215 2216 ide_proc_register_driver(drive, tape->driver); 2217} 2218 2219static void ide_tape_remove(ide_drive_t *drive) 2220{ 2221 idetape_tape_t *tape = drive->driver_data; 2222 2223 ide_proc_unregister_driver(drive, tape->driver); 2224 device_del(&tape->dev); 2225 ide_unregister_region(tape->disk); 2226 2227 mutex_lock(&idetape_ref_mutex); 2228 put_device(&tape->dev); 2229 mutex_unlock(&idetape_ref_mutex); 2230} 2231 2232static void ide_tape_release(struct device *dev) 2233{ 2234 struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj); 2235 ide_drive_t *drive = tape->drive; 2236 struct gendisk *g = tape->disk; 2237 2238 BUG_ON(tape->merge_bh_size); 2239 2240 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2241 drive->driver_data = NULL; 2242 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2243 device_destroy(idetape_sysfs_class, 2244 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2245 idetape_devs[tape->minor] = NULL; 2246 g->private_data = NULL; 2247 put_disk(g); 2248 kfree(tape); 2249} 2250 2251#ifdef CONFIG_IDE_PROC_FS 2252static int proc_idetape_read_name 2253 (char *page, char **start, off_t off, int count, int *eof, void *data) 2254{ 2255 ide_drive_t *drive = (ide_drive_t *) data; 2256 idetape_tape_t *tape = drive->driver_data; 2257 char *out = page; 2258 int len; 2259 2260 len = sprintf(out, "%s\n", tape->name); 2261 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2262} 2263 2264static ide_proc_entry_t idetape_proc[] = { 2265 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2266 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2267 { NULL, 0, NULL, NULL } 2268}; 2269 2270static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive) 2271{ 2272 return idetape_proc; 2273} 2274 2275static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive) 2276{ 2277 return idetape_settings; 2278} 2279#endif 2280 2281static int ide_tape_probe(ide_drive_t *); 2282 2283static struct ide_driver idetape_driver = { 2284 .gen_driver = { 2285 .owner = THIS_MODULE, 2286 .name = "ide-tape", 2287 .bus = &ide_bus_type, 2288 }, 2289 .probe = ide_tape_probe, 2290 .remove = ide_tape_remove, 2291 .version = IDETAPE_VERSION, 2292 .do_request = idetape_do_request, 2293#ifdef CONFIG_IDE_PROC_FS 2294 .proc_entries = ide_tape_proc_entries, 2295 .proc_devsets = ide_tape_proc_devsets, 2296#endif 2297}; 2298 2299/* Our character device supporting functions, passed to register_chrdev. */ 2300static const struct file_operations idetape_fops = { 2301 .owner = THIS_MODULE, 2302 .read = idetape_chrdev_read, 2303 .write = idetape_chrdev_write, 2304 .ioctl = idetape_chrdev_ioctl, 2305 .open = idetape_chrdev_open, 2306 .release = idetape_chrdev_release, 2307}; 2308 2309static int idetape_open(struct block_device *bdev, fmode_t mode) 2310{ 2311 struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk); 2312 2313 if (!tape) 2314 return -ENXIO; 2315 2316 return 0; 2317} 2318 2319static int idetape_release(struct gendisk *disk, fmode_t mode) 2320{ 2321 struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj); 2322 2323 ide_tape_put(tape); 2324 return 0; 2325} 2326 2327static int idetape_ioctl(struct block_device *bdev, fmode_t mode, 2328 unsigned int cmd, unsigned long arg) 2329{ 2330 struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj); 2331 ide_drive_t *drive = tape->drive; 2332 int err = generic_ide_ioctl(drive, bdev, cmd, arg); 2333 if (err == -EINVAL) 2334 err = idetape_blkdev_ioctl(drive, cmd, arg); 2335 return err; 2336} 2337 2338static struct block_device_operations idetape_block_ops = { 2339 .owner = THIS_MODULE, 2340 .open = idetape_open, 2341 .release = idetape_release, 2342 .locked_ioctl = idetape_ioctl, 2343}; 2344 2345static int ide_tape_probe(ide_drive_t *drive) 2346{ 2347 idetape_tape_t *tape; 2348 struct gendisk *g; 2349 int minor; 2350 2351 if (!strstr("ide-tape", drive->driver_req)) 2352 goto failed; 2353 2354 if (drive->media != ide_tape) 2355 goto failed; 2356 2357 if ((drive->dev_flags & IDE_DFLAG_ID_READ) && 2358 ide_check_atapi_device(drive, DRV_NAME) == 0) { 2359 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2360 " the driver\n", drive->name); 2361 goto failed; 2362 } 2363 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2364 if (tape == NULL) { 2365 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2366 drive->name); 2367 goto failed; 2368 } 2369 2370 g = alloc_disk(1 << PARTN_BITS); 2371 if (!g) 2372 goto out_free_tape; 2373 2374 ide_init_disk(g, drive); 2375 2376 tape->dev.parent = &drive->gendev; 2377 tape->dev.release = ide_tape_release; 2378 dev_set_name(&tape->dev, dev_name(&drive->gendev)); 2379 2380 if (device_register(&tape->dev)) 2381 goto out_free_disk; 2382 2383 tape->drive = drive; 2384 tape->driver = &idetape_driver; 2385 tape->disk = g; 2386 2387 g->private_data = &tape->driver; 2388 2389 drive->driver_data = tape; 2390 2391 mutex_lock(&idetape_ref_mutex); 2392 for (minor = 0; idetape_devs[minor]; minor++) 2393 ; 2394 idetape_devs[minor] = tape; 2395 mutex_unlock(&idetape_ref_mutex); 2396 2397 idetape_setup(drive, tape, minor); 2398 2399 device_create(idetape_sysfs_class, &drive->gendev, 2400 MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name); 2401 device_create(idetape_sysfs_class, &drive->gendev, 2402 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2403 "n%s", tape->name); 2404 2405 g->fops = &idetape_block_ops; 2406 ide_register_region(g); 2407 2408 return 0; 2409 2410out_free_disk: 2411 put_disk(g); 2412out_free_tape: 2413 kfree(tape); 2414failed: 2415 return -ENODEV; 2416} 2417 2418static void __exit idetape_exit(void) 2419{ 2420 driver_unregister(&idetape_driver.gen_driver); 2421 class_destroy(idetape_sysfs_class); 2422 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2423} 2424 2425static int __init idetape_init(void) 2426{ 2427 int error = 1; 2428 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2429 if (IS_ERR(idetape_sysfs_class)) { 2430 idetape_sysfs_class = NULL; 2431 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2432 error = -EBUSY; 2433 goto out; 2434 } 2435 2436 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2437 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2438 " interface\n"); 2439 error = -EBUSY; 2440 goto out_free_class; 2441 } 2442 2443 error = driver_register(&idetape_driver.gen_driver); 2444 if (error) 2445 goto out_free_driver; 2446 2447 return 0; 2448 2449out_free_driver: 2450 driver_unregister(&idetape_driver.gen_driver); 2451out_free_class: 2452 class_destroy(idetape_sysfs_class); 2453out: 2454 return error; 2455} 2456 2457MODULE_ALIAS("ide:*m-tape*"); 2458module_init(idetape_init); 2459module_exit(idetape_exit); 2460MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2461MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2462MODULE_LICENSE("GPL"); 2463