ide-tape.c revision 6b544fcc8cd0a04eb42de9d1ecdd345e979d6ada
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 int 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 break; 309 count = min( 310 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 311 bcount); 312 drive->hwif->tp_ops->input_data(drive, NULL, bh->b_data + 313 atomic_read(&bh->b_count), count); 314 bcount -= count; 315 atomic_add(count, &bh->b_count); 316 if (atomic_read(&bh->b_count) == bh->b_size) { 317 bh = bh->b_reqnext; 318 if (bh) 319 atomic_set(&bh->b_count, 0); 320 } 321 } 322 323 pc->bh = bh; 324 325 return bcount; 326} 327 328static int idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 329 unsigned int bcount) 330{ 331 struct idetape_bh *bh = pc->bh; 332 int count; 333 334 while (bcount) { 335 if (bh == NULL) 336 break; 337 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 338 drive->hwif->tp_ops->output_data(drive, NULL, pc->b_data, count); 339 bcount -= count; 340 pc->b_data += count; 341 pc->b_count -= count; 342 if (!pc->b_count) { 343 bh = bh->b_reqnext; 344 pc->bh = bh; 345 if (bh) { 346 pc->b_data = bh->b_data; 347 pc->b_count = atomic_read(&bh->b_count); 348 } 349 } 350 } 351 352 return bcount; 353} 354 355static void idetape_update_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc) 356{ 357 struct idetape_bh *bh = pc->bh; 358 int count; 359 unsigned int bcount = pc->xferred; 360 361 if (pc->flags & PC_FLAG_WRITING) 362 return; 363 while (bcount) { 364 if (bh == NULL) { 365 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 366 __func__); 367 return; 368 } 369 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 370 atomic_set(&bh->b_count, count); 371 if (atomic_read(&bh->b_count) == bh->b_size) 372 bh = bh->b_reqnext; 373 bcount -= count; 374 } 375 pc->bh = bh; 376} 377 378/* 379 * called on each failed packet command retry to analyze the request sense. We 380 * currently do not utilize this information. 381 */ 382static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 383{ 384 idetape_tape_t *tape = drive->driver_data; 385 struct ide_atapi_pc *pc = drive->failed_pc; 386 387 tape->sense_key = sense[2] & 0xF; 388 tape->asc = sense[12]; 389 tape->ascq = sense[13]; 390 391 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 392 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 393 394 /* Correct pc->xferred by asking the tape. */ 395 if (pc->flags & PC_FLAG_DMA_ERROR) { 396 pc->xferred = pc->req_xfer - 397 tape->blk_size * 398 get_unaligned_be32(&sense[3]); 399 idetape_update_buffers(drive, pc); 400 } 401 402 /* 403 * If error was the result of a zero-length read or write command, 404 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 405 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 406 */ 407 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 408 /* length == 0 */ 409 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 410 if (tape->sense_key == 5) { 411 /* don't report an error, everything's ok */ 412 pc->error = 0; 413 /* don't retry read/write */ 414 pc->flags |= PC_FLAG_ABORT; 415 } 416 } 417 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 418 pc->error = IDE_DRV_ERROR_FILEMARK; 419 pc->flags |= PC_FLAG_ABORT; 420 } 421 if (pc->c[0] == WRITE_6) { 422 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 423 && tape->asc == 0x0 && tape->ascq == 0x2)) { 424 pc->error = IDE_DRV_ERROR_EOD; 425 pc->flags |= PC_FLAG_ABORT; 426 } 427 } 428 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 429 if (tape->sense_key == 8) { 430 pc->error = IDE_DRV_ERROR_EOD; 431 pc->flags |= PC_FLAG_ABORT; 432 } 433 if (!(pc->flags & PC_FLAG_ABORT) && 434 pc->xferred) 435 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 436 } 437} 438 439/* Free data buffers completely. */ 440static void ide_tape_kfree_buffer(idetape_tape_t *tape) 441{ 442 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 443 444 while (bh) { 445 u32 size = bh->b_size; 446 447 while (size) { 448 unsigned int order = fls(size >> PAGE_SHIFT)-1; 449 450 if (bh->b_data) 451 free_pages((unsigned long)bh->b_data, order); 452 453 size &= (order-1); 454 bh->b_data += (1 << order) * PAGE_SIZE; 455 } 456 prev_bh = bh; 457 bh = bh->b_reqnext; 458 kfree(prev_bh); 459 } 460} 461 462static void ide_tape_handle_dsc(ide_drive_t *); 463 464static int ide_tape_callback(ide_drive_t *drive, int dsc) 465{ 466 idetape_tape_t *tape = drive->driver_data; 467 struct ide_atapi_pc *pc = drive->pc; 468 struct request *rq = drive->hwif->rq; 469 int uptodate = pc->error ? 0 : 1; 470 int err = uptodate ? 0 : IDE_DRV_ERROR_GENERAL; 471 472 debug_log(DBG_PROCS, "Enter %s\n", __func__); 473 474 if (dsc) 475 ide_tape_handle_dsc(drive); 476 477 if (drive->failed_pc == pc) 478 drive->failed_pc = NULL; 479 480 if (pc->c[0] == REQUEST_SENSE) { 481 if (uptodate) 482 idetape_analyze_error(drive, pc->buf); 483 else 484 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 485 "itself - Aborting request!\n"); 486 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 487 int blocks = pc->xferred / tape->blk_size; 488 489 tape->avg_size += blocks * tape->blk_size; 490 491 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 492 tape->avg_speed = tape->avg_size * HZ / 493 (jiffies - tape->avg_time) / 1024; 494 tape->avg_size = 0; 495 tape->avg_time = jiffies; 496 } 497 498 tape->first_frame += blocks; 499 rq->current_nr_sectors -= blocks; 500 501 if (pc->error) { 502 uptodate = 0; 503 err = pc->error; 504 } 505 } else if (pc->c[0] == READ_POSITION && uptodate) { 506 u8 *readpos = pc->buf; 507 508 debug_log(DBG_SENSE, "BOP - %s\n", 509 (readpos[0] & 0x80) ? "Yes" : "No"); 510 debug_log(DBG_SENSE, "EOP - %s\n", 511 (readpos[0] & 0x40) ? "Yes" : "No"); 512 513 if (readpos[0] & 0x4) { 514 printk(KERN_INFO "ide-tape: Block location is unknown" 515 "to the tape\n"); 516 clear_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 517 uptodate = 0; 518 err = IDE_DRV_ERROR_GENERAL; 519 } else { 520 debug_log(DBG_SENSE, "Block Location - %u\n", 521 be32_to_cpup((__be32 *)&readpos[4])); 522 523 tape->partition = readpos[1]; 524 tape->first_frame = be32_to_cpup((__be32 *)&readpos[4]); 525 set_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags); 526 } 527 } 528 529 rq->errors = err; 530 531 return uptodate; 532} 533 534/* 535 * Postpone the current request so that ide.c will be able to service requests 536 * from another device on the same port while we are polling for DSC. 537 */ 538static void idetape_postpone_request(ide_drive_t *drive) 539{ 540 idetape_tape_t *tape = drive->driver_data; 541 542 debug_log(DBG_PROCS, "Enter %s\n", __func__); 543 544 tape->postponed_rq = drive->hwif->rq; 545 546 ide_stall_queue(drive, tape->dsc_poll_freq); 547} 548 549static void ide_tape_handle_dsc(ide_drive_t *drive) 550{ 551 idetape_tape_t *tape = drive->driver_data; 552 553 /* Media access command */ 554 tape->dsc_polling_start = jiffies; 555 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 556 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 557 /* Allow ide.c to handle other requests */ 558 idetape_postpone_request(drive); 559} 560 561static int ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 562 unsigned int bcount, int write) 563{ 564 unsigned int bleft; 565 566 if (write) 567 bleft = idetape_output_buffers(drive, pc, bcount); 568 else 569 bleft = idetape_input_buffers(drive, pc, bcount); 570 571 return bcount - bleft; 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. ide_tape_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 ide_tape_issue_pc(ide_drive_t *drive, 612 struct ide_cmd *cmd, 613 struct ide_atapi_pc *pc) 614{ 615 idetape_tape_t *tape = drive->driver_data; 616 617 if (drive->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 618 drive->failed_pc = pc; 619 620 /* Set the current packet command */ 621 drive->pc = pc; 622 623 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 624 (pc->flags & PC_FLAG_ABORT)) { 625 /* 626 * We will "abort" retrying a packet command in case legitimate 627 * error code was received (crossing a filemark, or end of the 628 * media, for example). 629 */ 630 if (!(pc->flags & PC_FLAG_ABORT)) { 631 if (!(pc->c[0] == TEST_UNIT_READY && 632 tape->sense_key == 2 && tape->asc == 4 && 633 (tape->ascq == 1 || tape->ascq == 8))) { 634 printk(KERN_ERR "ide-tape: %s: I/O error, " 635 "pc = %2x, key = %2x, " 636 "asc = %2x, ascq = %2x\n", 637 tape->name, pc->c[0], 638 tape->sense_key, tape->asc, 639 tape->ascq); 640 } 641 /* Giving up */ 642 pc->error = IDE_DRV_ERROR_GENERAL; 643 } 644 drive->failed_pc = NULL; 645 drive->pc_callback(drive, 0); 646 return ide_stopped; 647 } 648 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 649 650 pc->retries++; 651 652 return ide_issue_pc(drive, cmd); 653} 654 655/* A mode sense command is used to "sense" tape parameters. */ 656static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 657{ 658 ide_init_pc(pc); 659 pc->c[0] = MODE_SENSE; 660 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 661 /* DBD = 1 - Don't return block descriptors */ 662 pc->c[1] = 8; 663 pc->c[2] = page_code; 664 /* 665 * Changed pc->c[3] to 0 (255 will at best return unused info). 666 * 667 * For SCSI this byte is defined as subpage instead of high byte 668 * of length and some IDE drives seem to interpret it this way 669 * and return an error when 255 is used. 670 */ 671 pc->c[3] = 0; 672 /* We will just discard data in that case */ 673 pc->c[4] = 255; 674 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 675 pc->req_xfer = 12; 676 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 677 pc->req_xfer = 24; 678 else 679 pc->req_xfer = 50; 680} 681 682static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 683{ 684 ide_hwif_t *hwif = drive->hwif; 685 idetape_tape_t *tape = drive->driver_data; 686 struct ide_atapi_pc *pc = drive->pc; 687 u8 stat; 688 689 stat = hwif->tp_ops->read_status(hwif); 690 691 if (stat & ATA_DSC) { 692 if (stat & ATA_ERR) { 693 /* Error detected */ 694 if (pc->c[0] != TEST_UNIT_READY) 695 printk(KERN_ERR "ide-tape: %s: I/O error, ", 696 tape->name); 697 /* Retry operation */ 698 ide_retry_pc(drive); 699 return ide_stopped; 700 } 701 pc->error = 0; 702 } else { 703 pc->error = IDE_DRV_ERROR_GENERAL; 704 drive->failed_pc = NULL; 705 } 706 drive->pc_callback(drive, 0); 707 return ide_stopped; 708} 709 710static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 711 struct ide_atapi_pc *pc, struct request *rq, 712 u8 opcode) 713{ 714 struct idetape_bh *bh = (struct idetape_bh *)rq->special; 715 unsigned int length = rq->current_nr_sectors; 716 717 ide_init_pc(pc); 718 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 719 pc->c[1] = 1; 720 pc->bh = bh; 721 pc->buf = NULL; 722 pc->buf_size = length * tape->blk_size; 723 pc->req_xfer = pc->buf_size; 724 if (pc->req_xfer == tape->buffer_size) 725 pc->flags |= PC_FLAG_DMA_OK; 726 727 if (opcode == READ_6) { 728 pc->c[0] = READ_6; 729 atomic_set(&bh->b_count, 0); 730 } else if (opcode == WRITE_6) { 731 pc->c[0] = WRITE_6; 732 pc->flags |= PC_FLAG_WRITING; 733 pc->b_data = bh->b_data; 734 pc->b_count = atomic_read(&bh->b_count); 735 } 736 737 memcpy(rq->cmd, pc->c, 12); 738} 739 740static ide_startstop_t idetape_do_request(ide_drive_t *drive, 741 struct request *rq, sector_t block) 742{ 743 ide_hwif_t *hwif = drive->hwif; 744 idetape_tape_t *tape = drive->driver_data; 745 struct ide_atapi_pc *pc = NULL; 746 struct request *postponed_rq = tape->postponed_rq; 747 struct ide_cmd cmd; 748 u8 stat; 749 750 debug_log(DBG_SENSE, "sector: %llu, nr_sectors: %lu," 751 " current_nr_sectors: %u\n", 752 (unsigned long long)rq->sector, rq->nr_sectors, 753 rq->current_nr_sectors); 754 755 if (!(blk_special_request(rq) || blk_sense_request(rq))) { 756 /* We do not support buffer cache originated requests. */ 757 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 758 "request queue (%d)\n", drive->name, rq->cmd_type); 759 if (blk_fs_request(rq) == 0 && rq->errors == 0) 760 rq->errors = -EIO; 761 ide_complete_rq(drive, -EIO, ide_rq_bytes(rq)); 762 return ide_stopped; 763 } 764 765 /* Retry a failed packet command */ 766 if (drive->failed_pc && drive->pc->c[0] == REQUEST_SENSE) { 767 pc = drive->failed_pc; 768 goto out; 769 } 770 771 if (postponed_rq != NULL) 772 if (rq != postponed_rq) { 773 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 774 "Two DSC requests were queued\n"); 775 drive->failed_pc = NULL; 776 rq->errors = 0; 777 ide_complete_rq(drive, 0, blk_rq_bytes(rq)); 778 return ide_stopped; 779 } 780 781 tape->postponed_rq = NULL; 782 783 /* 784 * If the tape is still busy, postpone our request and service 785 * the other device meanwhile. 786 */ 787 stat = hwif->tp_ops->read_status(hwif); 788 789 if ((drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) == 0 && 790 (rq->cmd[13] & REQ_IDETAPE_PC2) == 0) 791 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 792 793 if (drive->dev_flags & IDE_DFLAG_POST_RESET) { 794 set_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags); 795 drive->dev_flags &= ~IDE_DFLAG_POST_RESET; 796 } 797 798 if (!test_and_clear_bit(IDE_AFLAG_IGNORE_DSC, &drive->atapi_flags) && 799 (stat & ATA_DSC) == 0) { 800 if (postponed_rq == NULL) { 801 tape->dsc_polling_start = jiffies; 802 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 803 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 804 } else if (time_after(jiffies, tape->dsc_timeout)) { 805 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 806 tape->name); 807 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 808 idetape_media_access_finished(drive); 809 return ide_stopped; 810 } else { 811 return ide_do_reset(drive); 812 } 813 } else if (time_after(jiffies, 814 tape->dsc_polling_start + 815 IDETAPE_DSC_MA_THRESHOLD)) 816 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 817 idetape_postpone_request(drive); 818 return ide_stopped; 819 } 820 if (rq->cmd[13] & REQ_IDETAPE_READ) { 821 pc = &tape->queued_pc; 822 ide_tape_create_rw_cmd(tape, pc, rq, READ_6); 823 goto out; 824 } 825 if (rq->cmd[13] & REQ_IDETAPE_WRITE) { 826 pc = &tape->queued_pc; 827 ide_tape_create_rw_cmd(tape, pc, rq, WRITE_6); 828 goto out; 829 } 830 if (rq->cmd[13] & REQ_IDETAPE_PC1) { 831 pc = (struct ide_atapi_pc *)rq->special; 832 rq->cmd[13] &= ~(REQ_IDETAPE_PC1); 833 rq->cmd[13] |= REQ_IDETAPE_PC2; 834 goto out; 835 } 836 if (rq->cmd[13] & REQ_IDETAPE_PC2) { 837 idetape_media_access_finished(drive); 838 return ide_stopped; 839 } 840 BUG(); 841 842out: 843 /* prepare sense request for this command */ 844 ide_prep_sense(drive, rq); 845 846 memset(&cmd, 0, sizeof(cmd)); 847 848 if (rq_data_dir(rq)) 849 cmd.tf_flags |= IDE_TFLAG_WRITE; 850 851 cmd.rq = rq; 852 853 return ide_tape_issue_pc(drive, &cmd, pc); 854} 855 856/* 857 * The function below uses __get_free_pages to allocate a data buffer of size 858 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 859 * much as possible. 860 * 861 * It returns a pointer to the newly allocated buffer, or NULL in case of 862 * failure. 863 */ 864static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 865 int full, int clear) 866{ 867 struct idetape_bh *prev_bh, *bh, *merge_bh; 868 int pages = tape->pages_per_buffer; 869 unsigned int order, b_allocd; 870 char *b_data = NULL; 871 872 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 873 bh = merge_bh; 874 if (bh == NULL) 875 goto abort; 876 877 order = fls(pages) - 1; 878 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 879 if (!bh->b_data) 880 goto abort; 881 b_allocd = (1 << order) * PAGE_SIZE; 882 pages &= (order-1); 883 884 if (clear) 885 memset(bh->b_data, 0, b_allocd); 886 bh->b_reqnext = NULL; 887 bh->b_size = b_allocd; 888 atomic_set(&bh->b_count, full ? bh->b_size : 0); 889 890 while (pages) { 891 order = fls(pages) - 1; 892 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 893 if (!b_data) 894 goto abort; 895 b_allocd = (1 << order) * PAGE_SIZE; 896 897 if (clear) 898 memset(b_data, 0, b_allocd); 899 900 /* newly allocated page frames below buffer header or ...*/ 901 if (bh->b_data == b_data + b_allocd) { 902 bh->b_size += b_allocd; 903 bh->b_data -= b_allocd; 904 if (full) 905 atomic_add(b_allocd, &bh->b_count); 906 continue; 907 } 908 /* they are above the header */ 909 if (b_data == bh->b_data + bh->b_size) { 910 bh->b_size += b_allocd; 911 if (full) 912 atomic_add(b_allocd, &bh->b_count); 913 continue; 914 } 915 prev_bh = bh; 916 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 917 if (!bh) { 918 free_pages((unsigned long) b_data, order); 919 goto abort; 920 } 921 bh->b_reqnext = NULL; 922 bh->b_data = b_data; 923 bh->b_size = b_allocd; 924 atomic_set(&bh->b_count, full ? bh->b_size : 0); 925 prev_bh->b_reqnext = bh; 926 927 pages &= (order-1); 928 } 929 930 bh->b_size -= tape->excess_bh_size; 931 if (full) 932 atomic_sub(tape->excess_bh_size, &bh->b_count); 933 return merge_bh; 934abort: 935 ide_tape_kfree_buffer(tape); 936 return NULL; 937} 938 939static int idetape_copy_stage_from_user(idetape_tape_t *tape, 940 const char __user *buf, int n) 941{ 942 struct idetape_bh *bh = tape->bh; 943 int count; 944 int ret = 0; 945 946 while (n) { 947 if (bh == NULL) { 948 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 949 __func__); 950 return 1; 951 } 952 count = min((unsigned int) 953 (bh->b_size - atomic_read(&bh->b_count)), 954 (unsigned int)n); 955 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 956 count)) 957 ret = 1; 958 n -= count; 959 atomic_add(count, &bh->b_count); 960 buf += count; 961 if (atomic_read(&bh->b_count) == bh->b_size) { 962 bh = bh->b_reqnext; 963 if (bh) 964 atomic_set(&bh->b_count, 0); 965 } 966 } 967 tape->bh = bh; 968 return ret; 969} 970 971static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 972 int n) 973{ 974 struct idetape_bh *bh = tape->bh; 975 int count; 976 int ret = 0; 977 978 while (n) { 979 if (bh == NULL) { 980 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 981 __func__); 982 return 1; 983 } 984 count = min(tape->b_count, n); 985 if (copy_to_user(buf, tape->b_data, count)) 986 ret = 1; 987 n -= count; 988 tape->b_data += count; 989 tape->b_count -= count; 990 buf += count; 991 if (!tape->b_count) { 992 bh = bh->b_reqnext; 993 tape->bh = bh; 994 if (bh) { 995 tape->b_data = bh->b_data; 996 tape->b_count = atomic_read(&bh->b_count); 997 } 998 } 999 } 1000 return ret; 1001} 1002 1003static void idetape_init_merge_buffer(idetape_tape_t *tape) 1004{ 1005 struct idetape_bh *bh = tape->merge_bh; 1006 tape->bh = tape->merge_bh; 1007 1008 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1009 atomic_set(&bh->b_count, 0); 1010 else { 1011 tape->b_data = bh->b_data; 1012 tape->b_count = atomic_read(&bh->b_count); 1013 } 1014} 1015 1016/* 1017 * Write a filemark if write_filemark=1. Flush the device buffers without 1018 * writing a filemark otherwise. 1019 */ 1020static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1021 struct ide_atapi_pc *pc, int write_filemark) 1022{ 1023 ide_init_pc(pc); 1024 pc->c[0] = WRITE_FILEMARKS; 1025 pc->c[4] = write_filemark; 1026 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1027} 1028 1029static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1030{ 1031 idetape_tape_t *tape = drive->driver_data; 1032 struct gendisk *disk = tape->disk; 1033 int load_attempted = 0; 1034 1035 /* Wait for the tape to become ready */ 1036 set_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1037 timeout += jiffies; 1038 while (time_before(jiffies, timeout)) { 1039 if (ide_do_test_unit_ready(drive, disk) == 0) 1040 return 0; 1041 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1042 || (tape->asc == 0x3A)) { 1043 /* no media */ 1044 if (load_attempted) 1045 return -ENOMEDIUM; 1046 ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1047 load_attempted = 1; 1048 /* not about to be ready */ 1049 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1050 (tape->ascq == 1 || tape->ascq == 8))) 1051 return -EIO; 1052 msleep(100); 1053 } 1054 return -EIO; 1055} 1056 1057static int idetape_flush_tape_buffers(ide_drive_t *drive) 1058{ 1059 struct ide_tape_obj *tape = drive->driver_data; 1060 struct ide_atapi_pc pc; 1061 int rc; 1062 1063 idetape_create_write_filemark_cmd(drive, &pc, 0); 1064 rc = ide_queue_pc_tail(drive, tape->disk, &pc); 1065 if (rc) 1066 return rc; 1067 idetape_wait_ready(drive, 60 * 5 * HZ); 1068 return 0; 1069} 1070 1071static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1072{ 1073 ide_init_pc(pc); 1074 pc->c[0] = READ_POSITION; 1075 pc->req_xfer = 20; 1076} 1077 1078static int idetape_read_position(ide_drive_t *drive) 1079{ 1080 idetape_tape_t *tape = drive->driver_data; 1081 struct ide_atapi_pc pc; 1082 int position; 1083 1084 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1085 1086 idetape_create_read_position_cmd(&pc); 1087 if (ide_queue_pc_tail(drive, tape->disk, &pc)) 1088 return -1; 1089 position = tape->first_frame; 1090 return position; 1091} 1092 1093static void idetape_create_locate_cmd(ide_drive_t *drive, 1094 struct ide_atapi_pc *pc, 1095 unsigned int block, u8 partition, int skip) 1096{ 1097 ide_init_pc(pc); 1098 pc->c[0] = POSITION_TO_ELEMENT; 1099 pc->c[1] = 2; 1100 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1101 pc->c[8] = partition; 1102 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1103} 1104 1105static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1106{ 1107 idetape_tape_t *tape = drive->driver_data; 1108 1109 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1110 return; 1111 1112 clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags); 1113 tape->merge_bh_size = 0; 1114 if (tape->merge_bh != NULL) { 1115 ide_tape_kfree_buffer(tape); 1116 tape->merge_bh = NULL; 1117 } 1118 1119 tape->chrdev_dir = IDETAPE_DIR_NONE; 1120} 1121 1122/* 1123 * Position the tape to the requested block using the LOCATE packet command. 1124 * A READ POSITION command is then issued to check where we are positioned. Like 1125 * all higher level operations, we queue the commands at the tail of the request 1126 * queue and wait for their completion. 1127 */ 1128static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1129 u8 partition, int skip) 1130{ 1131 idetape_tape_t *tape = drive->driver_data; 1132 struct gendisk *disk = tape->disk; 1133 int retval; 1134 struct ide_atapi_pc pc; 1135 1136 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1137 __ide_tape_discard_merge_buffer(drive); 1138 idetape_wait_ready(drive, 60 * 5 * HZ); 1139 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1140 retval = ide_queue_pc_tail(drive, disk, &pc); 1141 if (retval) 1142 return (retval); 1143 1144 idetape_create_read_position_cmd(&pc); 1145 return ide_queue_pc_tail(drive, disk, &pc); 1146} 1147 1148static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1149 int restore_position) 1150{ 1151 idetape_tape_t *tape = drive->driver_data; 1152 int seek, position; 1153 1154 __ide_tape_discard_merge_buffer(drive); 1155 if (restore_position) { 1156 position = idetape_read_position(drive); 1157 seek = position > 0 ? position : 0; 1158 if (idetape_position_tape(drive, seek, 0, 0)) { 1159 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1160 " %s\n", tape->name, __func__); 1161 return; 1162 } 1163 } 1164} 1165 1166/* 1167 * Generate a read/write request for the block device interface and wait for it 1168 * to be serviced. 1169 */ 1170static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1171 struct idetape_bh *bh) 1172{ 1173 idetape_tape_t *tape = drive->driver_data; 1174 struct request *rq; 1175 int ret, errors; 1176 1177 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1178 1179 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1180 rq->cmd_type = REQ_TYPE_SPECIAL; 1181 rq->cmd[13] = cmd; 1182 rq->rq_disk = tape->disk; 1183 rq->special = (void *)bh; 1184 rq->sector = tape->first_frame; 1185 rq->nr_sectors = blocks; 1186 rq->current_nr_sectors = blocks; 1187 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1188 1189 errors = rq->errors; 1190 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1191 blk_put_request(rq); 1192 1193 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1194 return 0; 1195 1196 if (tape->merge_bh) 1197 idetape_init_merge_buffer(tape); 1198 if (errors == IDE_DRV_ERROR_GENERAL) 1199 return -EIO; 1200 return ret; 1201} 1202 1203static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1204{ 1205 ide_init_pc(pc); 1206 pc->c[0] = INQUIRY; 1207 pc->c[4] = 254; 1208 pc->req_xfer = 254; 1209} 1210 1211static void idetape_create_rewind_cmd(ide_drive_t *drive, 1212 struct ide_atapi_pc *pc) 1213{ 1214 ide_init_pc(pc); 1215 pc->c[0] = REZERO_UNIT; 1216 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1217} 1218 1219static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1220{ 1221 ide_init_pc(pc); 1222 pc->c[0] = ERASE; 1223 pc->c[1] = 1; 1224 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1225} 1226 1227static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1228{ 1229 ide_init_pc(pc); 1230 pc->c[0] = SPACE; 1231 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1232 pc->c[1] = cmd; 1233 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1234} 1235 1236/* Queue up a character device originated write request. */ 1237static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1238{ 1239 idetape_tape_t *tape = drive->driver_data; 1240 1241 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1242 1243 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1244 blocks, tape->merge_bh); 1245} 1246 1247static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1248{ 1249 idetape_tape_t *tape = drive->driver_data; 1250 int blocks, min; 1251 struct idetape_bh *bh; 1252 1253 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1254 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1255 " but we are not writing.\n"); 1256 return; 1257 } 1258 if (tape->merge_bh_size > tape->buffer_size) { 1259 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1260 tape->merge_bh_size = tape->buffer_size; 1261 } 1262 if (tape->merge_bh_size) { 1263 blocks = tape->merge_bh_size / tape->blk_size; 1264 if (tape->merge_bh_size % tape->blk_size) { 1265 unsigned int i; 1266 1267 blocks++; 1268 i = tape->blk_size - tape->merge_bh_size % 1269 tape->blk_size; 1270 bh = tape->bh->b_reqnext; 1271 while (bh) { 1272 atomic_set(&bh->b_count, 0); 1273 bh = bh->b_reqnext; 1274 } 1275 bh = tape->bh; 1276 while (i) { 1277 if (bh == NULL) { 1278 printk(KERN_INFO "ide-tape: bug," 1279 " bh NULL\n"); 1280 break; 1281 } 1282 min = min(i, (unsigned int)(bh->b_size - 1283 atomic_read(&bh->b_count))); 1284 memset(bh->b_data + atomic_read(&bh->b_count), 1285 0, min); 1286 atomic_add(min, &bh->b_count); 1287 i -= min; 1288 bh = bh->b_reqnext; 1289 } 1290 } 1291 (void) idetape_add_chrdev_write_request(drive, blocks); 1292 tape->merge_bh_size = 0; 1293 } 1294 if (tape->merge_bh != NULL) { 1295 ide_tape_kfree_buffer(tape); 1296 tape->merge_bh = NULL; 1297 } 1298 tape->chrdev_dir = IDETAPE_DIR_NONE; 1299} 1300 1301static int idetape_init_read(ide_drive_t *drive) 1302{ 1303 idetape_tape_t *tape = drive->driver_data; 1304 int bytes_read; 1305 1306 /* Initialize read operation */ 1307 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1308 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1309 ide_tape_flush_merge_buffer(drive); 1310 idetape_flush_tape_buffers(drive); 1311 } 1312 if (tape->merge_bh || tape->merge_bh_size) { 1313 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1314 " 0 now\n"); 1315 tape->merge_bh_size = 0; 1316 } 1317 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1318 if (!tape->merge_bh) 1319 return -ENOMEM; 1320 tape->chrdev_dir = IDETAPE_DIR_READ; 1321 1322 /* 1323 * Issue a read 0 command to ensure that DSC handshake is 1324 * switched from completion mode to buffer available mode. 1325 * No point in issuing this if DSC overlap isn't supported, some 1326 * drives (Seagate STT3401A) will return an error. 1327 */ 1328 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1329 bytes_read = idetape_queue_rw_tail(drive, 1330 REQ_IDETAPE_READ, 0, 1331 tape->merge_bh); 1332 if (bytes_read < 0) { 1333 ide_tape_kfree_buffer(tape); 1334 tape->merge_bh = NULL; 1335 tape->chrdev_dir = IDETAPE_DIR_NONE; 1336 return bytes_read; 1337 } 1338 } 1339 } 1340 1341 return 0; 1342} 1343 1344/* called from idetape_chrdev_read() to service a chrdev read request. */ 1345static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1346{ 1347 idetape_tape_t *tape = drive->driver_data; 1348 1349 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1350 1351 /* If we are at a filemark, return a read length of 0 */ 1352 if (test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1353 return 0; 1354 1355 idetape_init_read(drive); 1356 1357 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1358 tape->merge_bh); 1359} 1360 1361static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1362{ 1363 idetape_tape_t *tape = drive->driver_data; 1364 struct idetape_bh *bh; 1365 int blocks; 1366 1367 while (bcount) { 1368 unsigned int count; 1369 1370 bh = tape->merge_bh; 1371 count = min(tape->buffer_size, bcount); 1372 bcount -= count; 1373 blocks = count / tape->blk_size; 1374 while (count) { 1375 atomic_set(&bh->b_count, 1376 min(count, (unsigned int)bh->b_size)); 1377 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1378 count -= atomic_read(&bh->b_count); 1379 bh = bh->b_reqnext; 1380 } 1381 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1382 tape->merge_bh); 1383 } 1384} 1385 1386/* 1387 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1388 * currently support only one partition. 1389 */ 1390static int idetape_rewind_tape(ide_drive_t *drive) 1391{ 1392 struct ide_tape_obj *tape = drive->driver_data; 1393 struct gendisk *disk = tape->disk; 1394 int retval; 1395 struct ide_atapi_pc pc; 1396 1397 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1398 1399 idetape_create_rewind_cmd(drive, &pc); 1400 retval = ide_queue_pc_tail(drive, disk, &pc); 1401 if (retval) 1402 return retval; 1403 1404 idetape_create_read_position_cmd(&pc); 1405 retval = ide_queue_pc_tail(drive, disk, &pc); 1406 if (retval) 1407 return retval; 1408 return 0; 1409} 1410 1411/* mtio.h compatible commands should be issued to the chrdev interface. */ 1412static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1413 unsigned long arg) 1414{ 1415 idetape_tape_t *tape = drive->driver_data; 1416 void __user *argp = (void __user *)arg; 1417 1418 struct idetape_config { 1419 int dsc_rw_frequency; 1420 int dsc_media_access_frequency; 1421 int nr_stages; 1422 } config; 1423 1424 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1425 1426 switch (cmd) { 1427 case 0x0340: 1428 if (copy_from_user(&config, argp, sizeof(config))) 1429 return -EFAULT; 1430 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1431 break; 1432 case 0x0350: 1433 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1434 config.nr_stages = 1; 1435 if (copy_to_user(argp, &config, sizeof(config))) 1436 return -EFAULT; 1437 break; 1438 default: 1439 return -EIO; 1440 } 1441 return 0; 1442} 1443 1444static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1445 int mt_count) 1446{ 1447 idetape_tape_t *tape = drive->driver_data; 1448 struct gendisk *disk = tape->disk; 1449 struct ide_atapi_pc pc; 1450 int retval, count = 0; 1451 int sprev = !!(tape->caps[4] & 0x20); 1452 1453 if (mt_count == 0) 1454 return 0; 1455 if (MTBSF == mt_op || MTBSFM == mt_op) { 1456 if (!sprev) 1457 return -EIO; 1458 mt_count = -mt_count; 1459 } 1460 1461 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1462 tape->merge_bh_size = 0; 1463 if (test_and_clear_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) 1464 ++count; 1465 ide_tape_discard_merge_buffer(drive, 0); 1466 } 1467 1468 switch (mt_op) { 1469 case MTFSF: 1470 case MTBSF: 1471 idetape_create_space_cmd(&pc, mt_count - count, 1472 IDETAPE_SPACE_OVER_FILEMARK); 1473 return ide_queue_pc_tail(drive, disk, &pc); 1474 case MTFSFM: 1475 case MTBSFM: 1476 if (!sprev) 1477 return -EIO; 1478 retval = idetape_space_over_filemarks(drive, MTFSF, 1479 mt_count - count); 1480 if (retval) 1481 return retval; 1482 count = (MTBSFM == mt_op ? 1 : -1); 1483 return idetape_space_over_filemarks(drive, MTFSF, count); 1484 default: 1485 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1486 mt_op); 1487 return -EIO; 1488 } 1489} 1490 1491/* 1492 * Our character device read / write functions. 1493 * 1494 * The tape is optimized to maximize throughput when it is transferring an 1495 * integral number of the "continuous transfer limit", which is a parameter of 1496 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1497 * 1498 * As of version 1.3 of the driver, the character device provides an abstract 1499 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1500 * same backup/restore procedure is supported. The driver will internally 1501 * convert the requests to the recommended transfer unit, so that an unmatch 1502 * between the user's block size to the recommended size will only result in a 1503 * (slightly) increased driver overhead, but will no longer hit performance. 1504 * This is not applicable to Onstream. 1505 */ 1506static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1507 size_t count, loff_t *ppos) 1508{ 1509 struct ide_tape_obj *tape = file->private_data; 1510 ide_drive_t *drive = tape->drive; 1511 ssize_t bytes_read, temp, actually_read = 0, rc; 1512 ssize_t ret = 0; 1513 u16 ctl = *(u16 *)&tape->caps[12]; 1514 1515 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1516 1517 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1518 if (test_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags)) 1519 if (count > tape->blk_size && 1520 (count % tape->blk_size) == 0) 1521 tape->user_bs_factor = count / tape->blk_size; 1522 } 1523 rc = idetape_init_read(drive); 1524 if (rc < 0) 1525 return rc; 1526 if (count == 0) 1527 return (0); 1528 if (tape->merge_bh_size) { 1529 actually_read = min((unsigned int)(tape->merge_bh_size), 1530 (unsigned int)count); 1531 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1532 ret = -EFAULT; 1533 buf += actually_read; 1534 tape->merge_bh_size -= actually_read; 1535 count -= actually_read; 1536 } 1537 while (count >= tape->buffer_size) { 1538 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1539 if (bytes_read <= 0) 1540 goto finish; 1541 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1542 ret = -EFAULT; 1543 buf += bytes_read; 1544 count -= bytes_read; 1545 actually_read += bytes_read; 1546 } 1547 if (count) { 1548 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1549 if (bytes_read <= 0) 1550 goto finish; 1551 temp = min((unsigned long)count, (unsigned long)bytes_read); 1552 if (idetape_copy_stage_to_user(tape, buf, temp)) 1553 ret = -EFAULT; 1554 actually_read += temp; 1555 tape->merge_bh_size = bytes_read-temp; 1556 } 1557finish: 1558 if (!actually_read && test_bit(IDE_AFLAG_FILEMARK, &drive->atapi_flags)) { 1559 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1560 1561 idetape_space_over_filemarks(drive, MTFSF, 1); 1562 return 0; 1563 } 1564 1565 return ret ? ret : actually_read; 1566} 1567 1568static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1569 size_t count, loff_t *ppos) 1570{ 1571 struct ide_tape_obj *tape = file->private_data; 1572 ide_drive_t *drive = tape->drive; 1573 ssize_t actually_written = 0; 1574 ssize_t ret = 0; 1575 u16 ctl = *(u16 *)&tape->caps[12]; 1576 1577 /* The drive is write protected. */ 1578 if (tape->write_prot) 1579 return -EACCES; 1580 1581 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1582 1583 /* Initialize write operation */ 1584 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1585 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1586 ide_tape_discard_merge_buffer(drive, 1); 1587 if (tape->merge_bh || tape->merge_bh_size) { 1588 printk(KERN_ERR "ide-tape: merge_bh_size " 1589 "should be 0 now\n"); 1590 tape->merge_bh_size = 0; 1591 } 1592 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1593 if (!tape->merge_bh) 1594 return -ENOMEM; 1595 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1596 idetape_init_merge_buffer(tape); 1597 1598 /* 1599 * Issue a write 0 command to ensure that DSC handshake is 1600 * switched from completion mode to buffer available mode. No 1601 * point in issuing this if DSC overlap isn't supported, some 1602 * drives (Seagate STT3401A) will return an error. 1603 */ 1604 if (drive->dev_flags & IDE_DFLAG_DSC_OVERLAP) { 1605 ssize_t retval = idetape_queue_rw_tail(drive, 1606 REQ_IDETAPE_WRITE, 0, 1607 tape->merge_bh); 1608 if (retval < 0) { 1609 ide_tape_kfree_buffer(tape); 1610 tape->merge_bh = NULL; 1611 tape->chrdev_dir = IDETAPE_DIR_NONE; 1612 return retval; 1613 } 1614 } 1615 } 1616 if (count == 0) 1617 return (0); 1618 if (tape->merge_bh_size) { 1619 if (tape->merge_bh_size >= tape->buffer_size) { 1620 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1621 tape->merge_bh_size = 0; 1622 } 1623 actually_written = min((unsigned int) 1624 (tape->buffer_size - tape->merge_bh_size), 1625 (unsigned int)count); 1626 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1627 ret = -EFAULT; 1628 buf += actually_written; 1629 tape->merge_bh_size += actually_written; 1630 count -= actually_written; 1631 1632 if (tape->merge_bh_size == tape->buffer_size) { 1633 ssize_t retval; 1634 tape->merge_bh_size = 0; 1635 retval = idetape_add_chrdev_write_request(drive, ctl); 1636 if (retval <= 0) 1637 return (retval); 1638 } 1639 } 1640 while (count >= tape->buffer_size) { 1641 ssize_t retval; 1642 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1643 ret = -EFAULT; 1644 buf += tape->buffer_size; 1645 count -= tape->buffer_size; 1646 retval = idetape_add_chrdev_write_request(drive, ctl); 1647 actually_written += tape->buffer_size; 1648 if (retval <= 0) 1649 return (retval); 1650 } 1651 if (count) { 1652 actually_written += count; 1653 if (idetape_copy_stage_from_user(tape, buf, count)) 1654 ret = -EFAULT; 1655 tape->merge_bh_size += count; 1656 } 1657 return ret ? ret : actually_written; 1658} 1659 1660static int idetape_write_filemark(ide_drive_t *drive) 1661{ 1662 struct ide_tape_obj *tape = drive->driver_data; 1663 struct ide_atapi_pc pc; 1664 1665 /* Write a filemark */ 1666 idetape_create_write_filemark_cmd(drive, &pc, 1); 1667 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1668 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1669 return -EIO; 1670 } 1671 return 0; 1672} 1673 1674/* 1675 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1676 * requested. 1677 * 1678 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1679 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1680 * usually not supported. 1681 * 1682 * The following commands are currently not supported: 1683 * 1684 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1685 * MT_ST_WRITE_THRESHOLD. 1686 */ 1687static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1688{ 1689 idetape_tape_t *tape = drive->driver_data; 1690 struct gendisk *disk = tape->disk; 1691 struct ide_atapi_pc pc; 1692 int i, retval; 1693 1694 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1695 mt_op, mt_count); 1696 1697 switch (mt_op) { 1698 case MTFSF: 1699 case MTFSFM: 1700 case MTBSF: 1701 case MTBSFM: 1702 if (!mt_count) 1703 return 0; 1704 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1705 default: 1706 break; 1707 } 1708 1709 switch (mt_op) { 1710 case MTWEOF: 1711 if (tape->write_prot) 1712 return -EACCES; 1713 ide_tape_discard_merge_buffer(drive, 1); 1714 for (i = 0; i < mt_count; i++) { 1715 retval = idetape_write_filemark(drive); 1716 if (retval) 1717 return retval; 1718 } 1719 return 0; 1720 case MTREW: 1721 ide_tape_discard_merge_buffer(drive, 0); 1722 if (idetape_rewind_tape(drive)) 1723 return -EIO; 1724 return 0; 1725 case MTLOAD: 1726 ide_tape_discard_merge_buffer(drive, 0); 1727 return ide_do_start_stop(drive, disk, IDETAPE_LU_LOAD_MASK); 1728 case MTUNLOAD: 1729 case MTOFFL: 1730 /* 1731 * If door is locked, attempt to unlock before 1732 * attempting to eject. 1733 */ 1734 if (tape->door_locked) { 1735 if (!ide_set_media_lock(drive, disk, 0)) 1736 tape->door_locked = DOOR_UNLOCKED; 1737 } 1738 ide_tape_discard_merge_buffer(drive, 0); 1739 retval = ide_do_start_stop(drive, disk, !IDETAPE_LU_LOAD_MASK); 1740 if (!retval) 1741 clear_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags); 1742 return retval; 1743 case MTNOP: 1744 ide_tape_discard_merge_buffer(drive, 0); 1745 return idetape_flush_tape_buffers(drive); 1746 case MTRETEN: 1747 ide_tape_discard_merge_buffer(drive, 0); 1748 return ide_do_start_stop(drive, disk, 1749 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 1750 case MTEOM: 1751 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 1752 return ide_queue_pc_tail(drive, disk, &pc); 1753 case MTERASE: 1754 (void)idetape_rewind_tape(drive); 1755 idetape_create_erase_cmd(&pc); 1756 return ide_queue_pc_tail(drive, disk, &pc); 1757 case MTSETBLK: 1758 if (mt_count) { 1759 if (mt_count < tape->blk_size || 1760 mt_count % tape->blk_size) 1761 return -EIO; 1762 tape->user_bs_factor = mt_count / tape->blk_size; 1763 clear_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1764 } else 1765 set_bit(IDE_AFLAG_DETECT_BS, &drive->atapi_flags); 1766 return 0; 1767 case MTSEEK: 1768 ide_tape_discard_merge_buffer(drive, 0); 1769 return idetape_position_tape(drive, 1770 mt_count * tape->user_bs_factor, tape->partition, 0); 1771 case MTSETPART: 1772 ide_tape_discard_merge_buffer(drive, 0); 1773 return idetape_position_tape(drive, 0, mt_count, 0); 1774 case MTFSR: 1775 case MTBSR: 1776 case MTLOCK: 1777 retval = ide_set_media_lock(drive, disk, 1); 1778 if (retval) 1779 return retval; 1780 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 1781 return 0; 1782 case MTUNLOCK: 1783 retval = ide_set_media_lock(drive, disk, 0); 1784 if (retval) 1785 return retval; 1786 tape->door_locked = DOOR_UNLOCKED; 1787 return 0; 1788 default: 1789 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1790 mt_op); 1791 return -EIO; 1792 } 1793} 1794 1795/* 1796 * Our character device ioctls. General mtio.h magnetic io commands are 1797 * supported here, and not in the corresponding block interface. Our own 1798 * ide-tape ioctls are supported on both interfaces. 1799 */ 1800static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 1801 unsigned int cmd, unsigned long arg) 1802{ 1803 struct ide_tape_obj *tape = file->private_data; 1804 ide_drive_t *drive = tape->drive; 1805 struct mtop mtop; 1806 struct mtget mtget; 1807 struct mtpos mtpos; 1808 int block_offset = 0, position = tape->first_frame; 1809 void __user *argp = (void __user *)arg; 1810 1811 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 1812 1813 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1814 ide_tape_flush_merge_buffer(drive); 1815 idetape_flush_tape_buffers(drive); 1816 } 1817 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 1818 block_offset = tape->merge_bh_size / 1819 (tape->blk_size * tape->user_bs_factor); 1820 position = idetape_read_position(drive); 1821 if (position < 0) 1822 return -EIO; 1823 } 1824 switch (cmd) { 1825 case MTIOCTOP: 1826 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 1827 return -EFAULT; 1828 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 1829 case MTIOCGET: 1830 memset(&mtget, 0, sizeof(struct mtget)); 1831 mtget.mt_type = MT_ISSCSI2; 1832 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 1833 mtget.mt_dsreg = 1834 ((tape->blk_size * tape->user_bs_factor) 1835 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 1836 1837 if (tape->drv_write_prot) 1838 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 1839 1840 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 1841 return -EFAULT; 1842 return 0; 1843 case MTIOCPOS: 1844 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 1845 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 1846 return -EFAULT; 1847 return 0; 1848 default: 1849 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1850 ide_tape_discard_merge_buffer(drive, 1); 1851 return idetape_blkdev_ioctl(drive, cmd, arg); 1852 } 1853} 1854 1855/* 1856 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 1857 * block size with the reported value. 1858 */ 1859static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 1860{ 1861 idetape_tape_t *tape = drive->driver_data; 1862 struct ide_atapi_pc pc; 1863 1864 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 1865 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 1866 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 1867 if (tape->blk_size == 0) { 1868 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 1869 "block size, assuming 32k\n"); 1870 tape->blk_size = 32768; 1871 } 1872 return; 1873 } 1874 tape->blk_size = (pc.buf[4 + 5] << 16) + 1875 (pc.buf[4 + 6] << 8) + 1876 pc.buf[4 + 7]; 1877 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 1878} 1879 1880static int idetape_chrdev_open(struct inode *inode, struct file *filp) 1881{ 1882 unsigned int minor = iminor(inode), i = minor & ~0xc0; 1883 ide_drive_t *drive; 1884 idetape_tape_t *tape; 1885 int retval; 1886 1887 if (i >= MAX_HWIFS * MAX_DRIVES) 1888 return -ENXIO; 1889 1890 lock_kernel(); 1891 tape = ide_tape_chrdev_get(i); 1892 if (!tape) { 1893 unlock_kernel(); 1894 return -ENXIO; 1895 } 1896 1897 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1898 1899 /* 1900 * We really want to do nonseekable_open(inode, filp); here, but some 1901 * versions of tar incorrectly call lseek on tapes and bail out if that 1902 * fails. So we disallow pread() and pwrite(), but permit lseeks. 1903 */ 1904 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 1905 1906 drive = tape->drive; 1907 1908 filp->private_data = tape; 1909 1910 if (test_and_set_bit(IDE_AFLAG_BUSY, &drive->atapi_flags)) { 1911 retval = -EBUSY; 1912 goto out_put_tape; 1913 } 1914 1915 retval = idetape_wait_ready(drive, 60 * HZ); 1916 if (retval) { 1917 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1918 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 1919 goto out_put_tape; 1920 } 1921 1922 idetape_read_position(drive); 1923 if (!test_bit(IDE_AFLAG_ADDRESS_VALID, &drive->atapi_flags)) 1924 (void)idetape_rewind_tape(drive); 1925 1926 /* Read block size and write protect status from drive. */ 1927 ide_tape_get_bsize_from_bdesc(drive); 1928 1929 /* Set write protect flag if device is opened as read-only. */ 1930 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 1931 tape->write_prot = 1; 1932 else 1933 tape->write_prot = tape->drv_write_prot; 1934 1935 /* Make sure drive isn't write protected if user wants to write. */ 1936 if (tape->write_prot) { 1937 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 1938 (filp->f_flags & O_ACCMODE) == O_RDWR) { 1939 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 1940 retval = -EROFS; 1941 goto out_put_tape; 1942 } 1943 } 1944 1945 /* Lock the tape drive door so user can't eject. */ 1946 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1947 if (!ide_set_media_lock(drive, tape->disk, 1)) { 1948 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 1949 tape->door_locked = DOOR_LOCKED; 1950 } 1951 } 1952 unlock_kernel(); 1953 return 0; 1954 1955out_put_tape: 1956 ide_tape_put(tape); 1957 unlock_kernel(); 1958 return retval; 1959} 1960 1961static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 1962{ 1963 idetape_tape_t *tape = drive->driver_data; 1964 1965 ide_tape_flush_merge_buffer(drive); 1966 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 1967 if (tape->merge_bh != NULL) { 1968 idetape_pad_zeros(drive, tape->blk_size * 1969 (tape->user_bs_factor - 1)); 1970 ide_tape_kfree_buffer(tape); 1971 tape->merge_bh = NULL; 1972 } 1973 idetape_write_filemark(drive); 1974 idetape_flush_tape_buffers(drive); 1975 idetape_flush_tape_buffers(drive); 1976} 1977 1978static int idetape_chrdev_release(struct inode *inode, struct file *filp) 1979{ 1980 struct ide_tape_obj *tape = filp->private_data; 1981 ide_drive_t *drive = tape->drive; 1982 unsigned int minor = iminor(inode); 1983 1984 lock_kernel(); 1985 tape = drive->driver_data; 1986 1987 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1988 1989 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1990 idetape_write_release(drive, minor); 1991 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1992 if (minor < 128) 1993 ide_tape_discard_merge_buffer(drive, 1); 1994 } 1995 1996 if (minor < 128 && test_bit(IDE_AFLAG_MEDIUM_PRESENT, &drive->atapi_flags)) 1997 (void) idetape_rewind_tape(drive); 1998 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 1999 if (tape->door_locked == DOOR_LOCKED) { 2000 if (!ide_set_media_lock(drive, tape->disk, 0)) 2001 tape->door_locked = DOOR_UNLOCKED; 2002 } 2003 } 2004 clear_bit(IDE_AFLAG_BUSY, &drive->atapi_flags); 2005 ide_tape_put(tape); 2006 unlock_kernel(); 2007 return 0; 2008} 2009 2010static void idetape_get_inquiry_results(ide_drive_t *drive) 2011{ 2012 idetape_tape_t *tape = drive->driver_data; 2013 struct ide_atapi_pc pc; 2014 u8 pc_buf[256]; 2015 char fw_rev[4], vendor_id[8], product_id[16]; 2016 2017 idetape_create_inquiry_cmd(&pc); 2018 pc.buf = &pc_buf[0]; 2019 pc.buf_size = sizeof(pc_buf); 2020 2021 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2022 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2023 tape->name); 2024 return; 2025 } 2026 memcpy(vendor_id, &pc.buf[8], 8); 2027 memcpy(product_id, &pc.buf[16], 16); 2028 memcpy(fw_rev, &pc.buf[32], 4); 2029 2030 ide_fixstring(vendor_id, 8, 0); 2031 ide_fixstring(product_id, 16, 0); 2032 ide_fixstring(fw_rev, 4, 0); 2033 2034 printk(KERN_INFO "ide-tape: %s <-> %s: %.8s %.16s rev %.4s\n", 2035 drive->name, tape->name, vendor_id, product_id, fw_rev); 2036} 2037 2038/* 2039 * Ask the tape about its various parameters. In particular, we will adjust our 2040 * data transfer buffer size to the recommended value as returned by the tape. 2041 */ 2042static void idetape_get_mode_sense_results(ide_drive_t *drive) 2043{ 2044 idetape_tape_t *tape = drive->driver_data; 2045 struct ide_atapi_pc pc; 2046 u8 *caps; 2047 u8 speed, max_speed; 2048 2049 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2050 if (ide_queue_pc_tail(drive, tape->disk, &pc)) { 2051 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2052 " some default values\n"); 2053 tape->blk_size = 512; 2054 put_unaligned(52, (u16 *)&tape->caps[12]); 2055 put_unaligned(540, (u16 *)&tape->caps[14]); 2056 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2057 return; 2058 } 2059 caps = pc.buf + 4 + pc.buf[3]; 2060 2061 /* convert to host order and save for later use */ 2062 speed = be16_to_cpup((__be16 *)&caps[14]); 2063 max_speed = be16_to_cpup((__be16 *)&caps[8]); 2064 2065 *(u16 *)&caps[8] = max_speed; 2066 *(u16 *)&caps[12] = be16_to_cpup((__be16 *)&caps[12]); 2067 *(u16 *)&caps[14] = speed; 2068 *(u16 *)&caps[16] = be16_to_cpup((__be16 *)&caps[16]); 2069 2070 if (!speed) { 2071 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2072 "(assuming 650KB/sec)\n", drive->name); 2073 *(u16 *)&caps[14] = 650; 2074 } 2075 if (!max_speed) { 2076 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2077 "(assuming 650KB/sec)\n", drive->name); 2078 *(u16 *)&caps[8] = 650; 2079 } 2080 2081 memcpy(&tape->caps, caps, 20); 2082 2083 /* device lacks locking support according to capabilities page */ 2084 if ((caps[6] & 1) == 0) 2085 drive->dev_flags &= ~IDE_DFLAG_DOORLOCKING; 2086 2087 if (caps[7] & 0x02) 2088 tape->blk_size = 512; 2089 else if (caps[7] & 0x04) 2090 tape->blk_size = 1024; 2091} 2092 2093#ifdef CONFIG_IDE_PROC_FS 2094#define ide_tape_devset_get(name, field) \ 2095static int get_##name(ide_drive_t *drive) \ 2096{ \ 2097 idetape_tape_t *tape = drive->driver_data; \ 2098 return tape->field; \ 2099} 2100 2101#define ide_tape_devset_set(name, field) \ 2102static int set_##name(ide_drive_t *drive, int arg) \ 2103{ \ 2104 idetape_tape_t *tape = drive->driver_data; \ 2105 tape->field = arg; \ 2106 return 0; \ 2107} 2108 2109#define ide_tape_devset_rw_field(_name, _field) \ 2110ide_tape_devset_get(_name, _field) \ 2111ide_tape_devset_set(_name, _field) \ 2112IDE_DEVSET(_name, DS_SYNC, get_##_name, set_##_name) 2113 2114#define ide_tape_devset_r_field(_name, _field) \ 2115ide_tape_devset_get(_name, _field) \ 2116IDE_DEVSET(_name, 0, get_##_name, NULL) 2117 2118static int mulf_tdsc(ide_drive_t *drive) { return 1000; } 2119static int divf_tdsc(ide_drive_t *drive) { return HZ; } 2120static int divf_buffer(ide_drive_t *drive) { return 2; } 2121static int divf_buffer_size(ide_drive_t *drive) { return 1024; } 2122 2123ide_devset_rw_flag(dsc_overlap, IDE_DFLAG_DSC_OVERLAP); 2124 2125ide_tape_devset_rw_field(debug_mask, debug_mask); 2126ide_tape_devset_rw_field(tdsc, best_dsc_rw_freq); 2127 2128ide_tape_devset_r_field(avg_speed, avg_speed); 2129ide_tape_devset_r_field(speed, caps[14]); 2130ide_tape_devset_r_field(buffer, caps[16]); 2131ide_tape_devset_r_field(buffer_size, buffer_size); 2132 2133static const struct ide_proc_devset idetape_settings[] = { 2134 __IDE_PROC_DEVSET(avg_speed, 0, 0xffff, NULL, NULL), 2135 __IDE_PROC_DEVSET(buffer, 0, 0xffff, NULL, divf_buffer), 2136 __IDE_PROC_DEVSET(buffer_size, 0, 0xffff, NULL, divf_buffer_size), 2137 __IDE_PROC_DEVSET(debug_mask, 0, 0xffff, NULL, NULL), 2138 __IDE_PROC_DEVSET(dsc_overlap, 0, 1, NULL, NULL), 2139 __IDE_PROC_DEVSET(speed, 0, 0xffff, NULL, NULL), 2140 __IDE_PROC_DEVSET(tdsc, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 2141 mulf_tdsc, divf_tdsc), 2142 { NULL }, 2143}; 2144#endif 2145 2146/* 2147 * The function below is called to: 2148 * 2149 * 1. Initialize our various state variables. 2150 * 2. Ask the tape for its capabilities. 2151 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2152 * is chosen based on the recommendation which we received in step 2. 2153 * 2154 * Note that at this point ide.c already assigned us an irq, so that we can 2155 * queue requests here and wait for their completion. 2156 */ 2157static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2158{ 2159 unsigned long t; 2160 int speed; 2161 int buffer_size; 2162 u16 *ctl = (u16 *)&tape->caps[12]; 2163 2164 drive->pc_callback = ide_tape_callback; 2165 drive->pc_update_buffers = idetape_update_buffers; 2166 drive->pc_io_buffers = ide_tape_io_buffers; 2167 2168 drive->dev_flags |= IDE_DFLAG_DSC_OVERLAP; 2169 2170 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2171 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2172 tape->name); 2173 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2174 } 2175 2176 /* Seagate Travan drives do not support DSC overlap. */ 2177 if (strstr((char *)&drive->id[ATA_ID_PROD], "Seagate STT3401")) 2178 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2179 2180 tape->minor = minor; 2181 tape->name[0] = 'h'; 2182 tape->name[1] = 't'; 2183 tape->name[2] = '0' + minor; 2184 tape->chrdev_dir = IDETAPE_DIR_NONE; 2185 2186 idetape_get_inquiry_results(drive); 2187 idetape_get_mode_sense_results(drive); 2188 ide_tape_get_bsize_from_bdesc(drive); 2189 tape->user_bs_factor = 1; 2190 tape->buffer_size = *ctl * tape->blk_size; 2191 while (tape->buffer_size > 0xffff) { 2192 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2193 *ctl /= 2; 2194 tape->buffer_size = *ctl * tape->blk_size; 2195 } 2196 buffer_size = tape->buffer_size; 2197 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2198 if (buffer_size % PAGE_SIZE) { 2199 tape->pages_per_buffer++; 2200 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2201 } 2202 2203 /* select the "best" DSC read/write polling freq */ 2204 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2205 2206 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2207 2208 /* 2209 * Ensure that the number we got makes sense; limit it within 2210 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2211 */ 2212 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2213 IDETAPE_DSC_RW_MAX); 2214 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2215 "%lums tDSC%s\n", 2216 drive->name, tape->name, *(u16 *)&tape->caps[14], 2217 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2218 tape->buffer_size / 1024, 2219 tape->best_dsc_rw_freq * 1000 / HZ, 2220 (drive->dev_flags & IDE_DFLAG_USING_DMA) ? ", DMA" : ""); 2221 2222 ide_proc_register_driver(drive, tape->driver); 2223} 2224 2225static void ide_tape_remove(ide_drive_t *drive) 2226{ 2227 idetape_tape_t *tape = drive->driver_data; 2228 2229 ide_proc_unregister_driver(drive, tape->driver); 2230 device_del(&tape->dev); 2231 ide_unregister_region(tape->disk); 2232 2233 mutex_lock(&idetape_ref_mutex); 2234 put_device(&tape->dev); 2235 mutex_unlock(&idetape_ref_mutex); 2236} 2237 2238static void ide_tape_release(struct device *dev) 2239{ 2240 struct ide_tape_obj *tape = to_ide_drv(dev, ide_tape_obj); 2241 ide_drive_t *drive = tape->drive; 2242 struct gendisk *g = tape->disk; 2243 2244 BUG_ON(tape->merge_bh_size); 2245 2246 drive->dev_flags &= ~IDE_DFLAG_DSC_OVERLAP; 2247 drive->driver_data = NULL; 2248 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2249 device_destroy(idetape_sysfs_class, 2250 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2251 idetape_devs[tape->minor] = NULL; 2252 g->private_data = NULL; 2253 put_disk(g); 2254 kfree(tape); 2255} 2256 2257#ifdef CONFIG_IDE_PROC_FS 2258static int proc_idetape_read_name 2259 (char *page, char **start, off_t off, int count, int *eof, void *data) 2260{ 2261 ide_drive_t *drive = (ide_drive_t *) data; 2262 idetape_tape_t *tape = drive->driver_data; 2263 char *out = page; 2264 int len; 2265 2266 len = sprintf(out, "%s\n", tape->name); 2267 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2268} 2269 2270static ide_proc_entry_t idetape_proc[] = { 2271 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2272 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2273 { NULL, 0, NULL, NULL } 2274}; 2275 2276static ide_proc_entry_t *ide_tape_proc_entries(ide_drive_t *drive) 2277{ 2278 return idetape_proc; 2279} 2280 2281static const struct ide_proc_devset *ide_tape_proc_devsets(ide_drive_t *drive) 2282{ 2283 return idetape_settings; 2284} 2285#endif 2286 2287static int ide_tape_probe(ide_drive_t *); 2288 2289static struct ide_driver idetape_driver = { 2290 .gen_driver = { 2291 .owner = THIS_MODULE, 2292 .name = "ide-tape", 2293 .bus = &ide_bus_type, 2294 }, 2295 .probe = ide_tape_probe, 2296 .remove = ide_tape_remove, 2297 .version = IDETAPE_VERSION, 2298 .do_request = idetape_do_request, 2299#ifdef CONFIG_IDE_PROC_FS 2300 .proc_entries = ide_tape_proc_entries, 2301 .proc_devsets = ide_tape_proc_devsets, 2302#endif 2303}; 2304 2305/* Our character device supporting functions, passed to register_chrdev. */ 2306static const struct file_operations idetape_fops = { 2307 .owner = THIS_MODULE, 2308 .read = idetape_chrdev_read, 2309 .write = idetape_chrdev_write, 2310 .ioctl = idetape_chrdev_ioctl, 2311 .open = idetape_chrdev_open, 2312 .release = idetape_chrdev_release, 2313}; 2314 2315static int idetape_open(struct block_device *bdev, fmode_t mode) 2316{ 2317 struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk); 2318 2319 if (!tape) 2320 return -ENXIO; 2321 2322 return 0; 2323} 2324 2325static int idetape_release(struct gendisk *disk, fmode_t mode) 2326{ 2327 struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj); 2328 2329 ide_tape_put(tape); 2330 return 0; 2331} 2332 2333static int idetape_ioctl(struct block_device *bdev, fmode_t mode, 2334 unsigned int cmd, unsigned long arg) 2335{ 2336 struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj); 2337 ide_drive_t *drive = tape->drive; 2338 int err = generic_ide_ioctl(drive, bdev, cmd, arg); 2339 if (err == -EINVAL) 2340 err = idetape_blkdev_ioctl(drive, cmd, arg); 2341 return err; 2342} 2343 2344static struct block_device_operations idetape_block_ops = { 2345 .owner = THIS_MODULE, 2346 .open = idetape_open, 2347 .release = idetape_release, 2348 .locked_ioctl = idetape_ioctl, 2349}; 2350 2351static int ide_tape_probe(ide_drive_t *drive) 2352{ 2353 idetape_tape_t *tape; 2354 struct gendisk *g; 2355 int minor; 2356 2357 if (!strstr("ide-tape", drive->driver_req)) 2358 goto failed; 2359 2360 if (drive->media != ide_tape) 2361 goto failed; 2362 2363 if ((drive->dev_flags & IDE_DFLAG_ID_READ) && 2364 ide_check_atapi_device(drive, DRV_NAME) == 0) { 2365 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2366 " the driver\n", drive->name); 2367 goto failed; 2368 } 2369 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2370 if (tape == NULL) { 2371 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2372 drive->name); 2373 goto failed; 2374 } 2375 2376 g = alloc_disk(1 << PARTN_BITS); 2377 if (!g) 2378 goto out_free_tape; 2379 2380 ide_init_disk(g, drive); 2381 2382 tape->dev.parent = &drive->gendev; 2383 tape->dev.release = ide_tape_release; 2384 dev_set_name(&tape->dev, dev_name(&drive->gendev)); 2385 2386 if (device_register(&tape->dev)) 2387 goto out_free_disk; 2388 2389 tape->drive = drive; 2390 tape->driver = &idetape_driver; 2391 tape->disk = g; 2392 2393 g->private_data = &tape->driver; 2394 2395 drive->driver_data = tape; 2396 2397 mutex_lock(&idetape_ref_mutex); 2398 for (minor = 0; idetape_devs[minor]; minor++) 2399 ; 2400 idetape_devs[minor] = tape; 2401 mutex_unlock(&idetape_ref_mutex); 2402 2403 idetape_setup(drive, tape, minor); 2404 2405 device_create(idetape_sysfs_class, &drive->gendev, 2406 MKDEV(IDETAPE_MAJOR, minor), NULL, "%s", tape->name); 2407 device_create(idetape_sysfs_class, &drive->gendev, 2408 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2409 "n%s", tape->name); 2410 2411 g->fops = &idetape_block_ops; 2412 ide_register_region(g); 2413 2414 return 0; 2415 2416out_free_disk: 2417 put_disk(g); 2418out_free_tape: 2419 kfree(tape); 2420failed: 2421 return -ENODEV; 2422} 2423 2424static void __exit idetape_exit(void) 2425{ 2426 driver_unregister(&idetape_driver.gen_driver); 2427 class_destroy(idetape_sysfs_class); 2428 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2429} 2430 2431static int __init idetape_init(void) 2432{ 2433 int error = 1; 2434 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2435 if (IS_ERR(idetape_sysfs_class)) { 2436 idetape_sysfs_class = NULL; 2437 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2438 error = -EBUSY; 2439 goto out; 2440 } 2441 2442 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2443 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2444 " interface\n"); 2445 error = -EBUSY; 2446 goto out_free_class; 2447 } 2448 2449 error = driver_register(&idetape_driver.gen_driver); 2450 if (error) 2451 goto out_free_driver; 2452 2453 return 0; 2454 2455out_free_driver: 2456 driver_unregister(&idetape_driver.gen_driver); 2457out_free_class: 2458 class_destroy(idetape_sysfs_class); 2459out: 2460 return error; 2461} 2462 2463MODULE_ALIAS("ide:*m-tape*"); 2464module_init(idetape_init); 2465module_exit(idetape_exit); 2466MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2467MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2468MODULE_LICENSE("GPL"); 2469