ide-tape.c revision 5985e6abbd89f969c17fd80ab864c80f089827a3
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 IDETAPE_VERSION "1.20" 19 20#include <linux/module.h> 21#include <linux/types.h> 22#include <linux/string.h> 23#include <linux/kernel.h> 24#include <linux/delay.h> 25#include <linux/timer.h> 26#include <linux/mm.h> 27#include <linux/interrupt.h> 28#include <linux/jiffies.h> 29#include <linux/major.h> 30#include <linux/errno.h> 31#include <linux/genhd.h> 32#include <linux/slab.h> 33#include <linux/pci.h> 34#include <linux/ide.h> 35#include <linux/smp_lock.h> 36#include <linux/completion.h> 37#include <linux/bitops.h> 38#include <linux/mutex.h> 39#include <scsi/scsi.h> 40 41#include <asm/byteorder.h> 42#include <linux/irq.h> 43#include <linux/uaccess.h> 44#include <linux/io.h> 45#include <asm/unaligned.h> 46#include <linux/mtio.h> 47 48enum { 49 /* output errors only */ 50 DBG_ERR = (1 << 0), 51 /* output all sense key/asc */ 52 DBG_SENSE = (1 << 1), 53 /* info regarding all chrdev-related procedures */ 54 DBG_CHRDEV = (1 << 2), 55 /* all remaining procedures */ 56 DBG_PROCS = (1 << 3), 57 /* buffer alloc info (pc_stack & rq_stack) */ 58 DBG_PCRQ_STACK = (1 << 4), 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 * With each packet command, we allocate a buffer of IDETAPE_PC_BUFFER_SIZE 85 * bytes. This is used for several packet commands (Not for READ/WRITE commands) 86 */ 87#define IDETAPE_PC_BUFFER_SIZE 256 88 89/* 90 * In various places in the driver, we need to allocate storage 91 * for packet commands and requests, which will remain valid while 92 * we leave the driver to wait for an interrupt or a timeout event. 93 */ 94#define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES) 95 96/* 97 * Some drives (for example, Seagate STT3401A Travan) require a very long 98 * timeout, because they don't return an interrupt or clear their busy bit 99 * until after the command completes (even retension commands). 100 */ 101#define IDETAPE_WAIT_CMD (900*HZ) 102 103/* 104 * The following parameter is used to select the point in the internal tape fifo 105 * in which we will start to refill the buffer. Decreasing the following 106 * parameter will improve the system's latency and interactive response, while 107 * using a high value might improve system throughput. 108 */ 109#define IDETAPE_FIFO_THRESHOLD 2 110 111/* 112 * DSC polling parameters. 113 * 114 * Polling for DSC (a single bit in the status register) is a very important 115 * function in ide-tape. There are two cases in which we poll for DSC: 116 * 117 * 1. Before a read/write packet command, to ensure that we can transfer data 118 * from/to the tape's data buffers, without causing an actual media access. 119 * In case the tape is not ready yet, we take out our request from the device 120 * request queue, so that ide.c could service requests from the other device 121 * on the same interface in the meantime. 122 * 123 * 2. After the successful initialization of a "media access packet command", 124 * which is a command that can take a long time to complete (the interval can 125 * range from several seconds to even an hour). Again, we postpone our request 126 * in the middle to free the bus for the other device. The polling frequency 127 * here should be lower than the read/write frequency since those media access 128 * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST 129 * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD 130 * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min). 131 * 132 * We also set a timeout for the timer, in case something goes wrong. The 133 * timeout should be longer then the maximum execution time of a tape operation. 134 */ 135 136/* DSC timings. */ 137#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */ 138#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */ 139#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */ 140#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */ 141#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */ 142#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */ 143#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */ 144 145/*************************** End of tunable parameters ***********************/ 146 147/* tape directions */ 148enum { 149 IDETAPE_DIR_NONE = (1 << 0), 150 IDETAPE_DIR_READ = (1 << 1), 151 IDETAPE_DIR_WRITE = (1 << 2), 152}; 153 154struct idetape_bh { 155 u32 b_size; 156 atomic_t b_count; 157 struct idetape_bh *b_reqnext; 158 char *b_data; 159}; 160 161/* Tape door status */ 162#define DOOR_UNLOCKED 0 163#define DOOR_LOCKED 1 164#define DOOR_EXPLICITLY_LOCKED 2 165 166/* Some defines for the SPACE command */ 167#define IDETAPE_SPACE_OVER_FILEMARK 1 168#define IDETAPE_SPACE_TO_EOD 3 169 170/* Some defines for the LOAD UNLOAD command */ 171#define IDETAPE_LU_LOAD_MASK 1 172#define IDETAPE_LU_RETENSION_MASK 2 173#define IDETAPE_LU_EOT_MASK 4 174 175/* 176 * Special requests for our block device strategy routine. 177 * 178 * In order to service a character device command, we add special requests to 179 * the tail of our block device request queue and wait for their completion. 180 */ 181 182enum { 183 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */ 184 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */ 185 REQ_IDETAPE_READ = (1 << 2), 186 REQ_IDETAPE_WRITE = (1 << 3), 187}; 188 189/* Error codes returned in rq->errors to the higher part of the driver. */ 190#define IDETAPE_ERROR_GENERAL 101 191#define IDETAPE_ERROR_FILEMARK 102 192#define IDETAPE_ERROR_EOD 103 193 194/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 195#define IDETAPE_BLOCK_DESCRIPTOR 0 196#define IDETAPE_CAPABILITIES_PAGE 0x2a 197 198/* Tape flag bits values. */ 199enum { 200 IDETAPE_FLAG_IGNORE_DSC = (1 << 0), 201 /* 0 When the tape position is unknown */ 202 IDETAPE_FLAG_ADDRESS_VALID = (1 << 1), 203 /* Device already opened */ 204 IDETAPE_FLAG_BUSY = (1 << 2), 205 /* Attempt to auto-detect the current user block size */ 206 IDETAPE_FLAG_DETECT_BS = (1 << 3), 207 /* Currently on a filemark */ 208 IDETAPE_FLAG_FILEMARK = (1 << 4), 209 /* DRQ interrupt device */ 210 IDETAPE_FLAG_DRQ_INTERRUPT = (1 << 5), 211 /* 0 = no tape is loaded, so we don't rewind after ejecting */ 212 IDETAPE_FLAG_MEDIUM_PRESENT = (1 << 6), 213}; 214 215/* 216 * Most of our global data which we need to save even as we leave the driver due 217 * to an interrupt or a timer event is stored in the struct defined below. 218 */ 219typedef struct ide_tape_obj { 220 ide_drive_t *drive; 221 ide_driver_t *driver; 222 struct gendisk *disk; 223 struct kref kref; 224 225 /* 226 * Since a typical character device operation requires more 227 * than one packet command, we provide here enough memory 228 * for the maximum of interconnected packet commands. 229 * The packet commands are stored in the circular array pc_stack. 230 * pc_stack_index points to the last used entry, and warps around 231 * to the start when we get to the last array entry. 232 * 233 * pc points to the current processed packet command. 234 * 235 * failed_pc points to the last failed packet command, or contains 236 * NULL if we do not need to retry any packet command. This is 237 * required since an additional packet command is needed before the 238 * retry, to get detailed information on what went wrong. 239 */ 240 /* Current packet command */ 241 struct ide_atapi_pc *pc; 242 /* Last failed packet command */ 243 struct ide_atapi_pc *failed_pc; 244 /* Packet command stack */ 245 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK]; 246 /* Next free packet command storage space */ 247 int pc_stack_index; 248 struct request rq_stack[IDETAPE_PC_STACK]; 249 /* We implement a circular array */ 250 int rq_stack_index; 251 252 /* 253 * DSC polling variables. 254 * 255 * While polling for DSC we use postponed_rq to postpone the current 256 * request so that ide.c will be able to service pending requests on the 257 * other device. Note that at most we will have only one DSC (usually 258 * data transfer) request in the device request queue. 259 */ 260 struct request *postponed_rq; 261 /* The time in which we started polling for DSC */ 262 unsigned long dsc_polling_start; 263 /* Timer used to poll for dsc */ 264 struct timer_list dsc_timer; 265 /* Read/Write dsc polling frequency */ 266 unsigned long best_dsc_rw_freq; 267 unsigned long dsc_poll_freq; 268 unsigned long dsc_timeout; 269 270 /* Read position information */ 271 u8 partition; 272 /* Current block */ 273 unsigned int first_frame; 274 275 /* Last error information */ 276 u8 sense_key, asc, ascq; 277 278 /* Character device operation */ 279 unsigned int minor; 280 /* device name */ 281 char name[4]; 282 /* Current character device data transfer direction */ 283 u8 chrdev_dir; 284 285 /* tape block size, usually 512 or 1024 bytes */ 286 unsigned short blk_size; 287 int user_bs_factor; 288 289 /* Copy of the tape's Capabilities and Mechanical Page */ 290 u8 caps[20]; 291 292 /* 293 * Active data transfer request parameters. 294 * 295 * At most, there is only one ide-tape originated data transfer request 296 * in the device request queue. This allows ide.c to easily service 297 * requests from the other device when we postpone our active request. 298 */ 299 300 /* Data buffer size chosen based on the tape's recommendation */ 301 int buffer_size; 302 /* merge buffer */ 303 struct idetape_bh *merge_bh; 304 /* size of the merge buffer */ 305 int merge_bh_size; 306 /* pointer to current buffer head within the merge buffer */ 307 struct idetape_bh *bh; 308 char *b_data; 309 int b_count; 310 311 int pages_per_buffer; 312 /* Wasted space in each stage */ 313 int excess_bh_size; 314 315 /* Status/Action flags: long for set_bit */ 316 unsigned long flags; 317 /* protects the ide-tape queue */ 318 spinlock_t lock; 319 320 /* Measures average tape speed */ 321 unsigned long avg_time; 322 int avg_size; 323 int avg_speed; 324 325 /* the door is currently locked */ 326 int door_locked; 327 /* the tape hardware is write protected */ 328 char drv_write_prot; 329 /* the tape is write protected (hardware or opened as read-only) */ 330 char write_prot; 331 332 u32 debug_mask; 333} idetape_tape_t; 334 335static DEFINE_MUTEX(idetape_ref_mutex); 336 337static struct class *idetape_sysfs_class; 338 339#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref) 340 341#define ide_tape_g(disk) \ 342 container_of((disk)->private_data, struct ide_tape_obj, driver) 343 344static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 345{ 346 struct ide_tape_obj *tape = NULL; 347 348 mutex_lock(&idetape_ref_mutex); 349 tape = ide_tape_g(disk); 350 if (tape) 351 kref_get(&tape->kref); 352 mutex_unlock(&idetape_ref_mutex); 353 return tape; 354} 355 356static void ide_tape_release(struct kref *); 357 358static void ide_tape_put(struct ide_tape_obj *tape) 359{ 360 mutex_lock(&idetape_ref_mutex); 361 kref_put(&tape->kref, ide_tape_release); 362 mutex_unlock(&idetape_ref_mutex); 363} 364 365/* 366 * The variables below are used for the character device interface. Additional 367 * state variables are defined in our ide_drive_t structure. 368 */ 369static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES]; 370 371#define ide_tape_f(file) ((file)->private_data) 372 373static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 374{ 375 struct ide_tape_obj *tape = NULL; 376 377 mutex_lock(&idetape_ref_mutex); 378 tape = idetape_devs[i]; 379 if (tape) 380 kref_get(&tape->kref); 381 mutex_unlock(&idetape_ref_mutex); 382 return tape; 383} 384 385static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 386 unsigned int bcount) 387{ 388 struct idetape_bh *bh = pc->bh; 389 int count; 390 391 while (bcount) { 392 if (bh == NULL) { 393 printk(KERN_ERR "ide-tape: bh == NULL in " 394 "idetape_input_buffers\n"); 395 ide_pad_transfer(drive, 0, bcount); 396 return; 397 } 398 count = min( 399 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 400 bcount); 401 drive->hwif->input_data(drive, NULL, bh->b_data + 402 atomic_read(&bh->b_count), count); 403 bcount -= count; 404 atomic_add(count, &bh->b_count); 405 if (atomic_read(&bh->b_count) == bh->b_size) { 406 bh = bh->b_reqnext; 407 if (bh) 408 atomic_set(&bh->b_count, 0); 409 } 410 } 411 pc->bh = bh; 412} 413 414static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 415 unsigned int bcount) 416{ 417 struct idetape_bh *bh = pc->bh; 418 int count; 419 420 while (bcount) { 421 if (bh == NULL) { 422 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 423 __func__); 424 return; 425 } 426 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 427 drive->hwif->output_data(drive, NULL, pc->b_data, count); 428 bcount -= count; 429 pc->b_data += count; 430 pc->b_count -= count; 431 if (!pc->b_count) { 432 bh = bh->b_reqnext; 433 pc->bh = bh; 434 if (bh) { 435 pc->b_data = bh->b_data; 436 pc->b_count = atomic_read(&bh->b_count); 437 } 438 } 439 } 440} 441 442static void idetape_update_buffers(struct ide_atapi_pc *pc) 443{ 444 struct idetape_bh *bh = pc->bh; 445 int count; 446 unsigned int bcount = pc->xferred; 447 448 if (pc->flags & PC_FLAG_WRITING) 449 return; 450 while (bcount) { 451 if (bh == NULL) { 452 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 453 __func__); 454 return; 455 } 456 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 457 atomic_set(&bh->b_count, count); 458 if (atomic_read(&bh->b_count) == bh->b_size) 459 bh = bh->b_reqnext; 460 bcount -= count; 461 } 462 pc->bh = bh; 463} 464 465/* 466 * idetape_next_pc_storage returns a pointer to a place in which we can 467 * safely store a packet command, even though we intend to leave the 468 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet 469 * commands is allocated at initialization time. 470 */ 471static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive) 472{ 473 idetape_tape_t *tape = drive->driver_data; 474 475 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index); 476 477 if (tape->pc_stack_index == IDETAPE_PC_STACK) 478 tape->pc_stack_index = 0; 479 return (&tape->pc_stack[tape->pc_stack_index++]); 480} 481 482/* 483 * idetape_next_rq_storage is used along with idetape_next_pc_storage. 484 * Since we queue packet commands in the request queue, we need to 485 * allocate a request, along with the allocation of a packet command. 486 */ 487 488/************************************************************** 489 * * 490 * This should get fixed to use kmalloc(.., GFP_ATOMIC) * 491 * followed later on by kfree(). -ml * 492 * * 493 **************************************************************/ 494 495static struct request *idetape_next_rq_storage(ide_drive_t *drive) 496{ 497 idetape_tape_t *tape = drive->driver_data; 498 499 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index); 500 501 if (tape->rq_stack_index == IDETAPE_PC_STACK) 502 tape->rq_stack_index = 0; 503 return (&tape->rq_stack[tape->rq_stack_index++]); 504} 505 506/* 507 * called on each failed packet command retry to analyze the request sense. We 508 * currently do not utilize this information. 509 */ 510static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 511{ 512 idetape_tape_t *tape = drive->driver_data; 513 struct ide_atapi_pc *pc = tape->failed_pc; 514 515 tape->sense_key = sense[2] & 0xF; 516 tape->asc = sense[12]; 517 tape->ascq = sense[13]; 518 519 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 520 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 521 522 /* Correct pc->xferred by asking the tape. */ 523 if (pc->flags & PC_FLAG_DMA_ERROR) { 524 pc->xferred = pc->req_xfer - 525 tape->blk_size * 526 get_unaligned_be32(&sense[3]); 527 idetape_update_buffers(pc); 528 } 529 530 /* 531 * If error was the result of a zero-length read or write command, 532 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 533 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 534 */ 535 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 536 /* length == 0 */ 537 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 538 if (tape->sense_key == 5) { 539 /* don't report an error, everything's ok */ 540 pc->error = 0; 541 /* don't retry read/write */ 542 pc->flags |= PC_FLAG_ABORT; 543 } 544 } 545 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 546 pc->error = IDETAPE_ERROR_FILEMARK; 547 pc->flags |= PC_FLAG_ABORT; 548 } 549 if (pc->c[0] == WRITE_6) { 550 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 551 && tape->asc == 0x0 && tape->ascq == 0x2)) { 552 pc->error = IDETAPE_ERROR_EOD; 553 pc->flags |= PC_FLAG_ABORT; 554 } 555 } 556 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 557 if (tape->sense_key == 8) { 558 pc->error = IDETAPE_ERROR_EOD; 559 pc->flags |= PC_FLAG_ABORT; 560 } 561 if (!(pc->flags & PC_FLAG_ABORT) && 562 pc->xferred) 563 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 564 } 565} 566 567/* Free data buffers completely. */ 568static void ide_tape_kfree_buffer(idetape_tape_t *tape) 569{ 570 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 571 572 while (bh) { 573 u32 size = bh->b_size; 574 575 while (size) { 576 unsigned int order = fls(size >> PAGE_SHIFT)-1; 577 578 if (bh->b_data) 579 free_pages((unsigned long)bh->b_data, order); 580 581 size &= (order-1); 582 bh->b_data += (1 << order) * PAGE_SIZE; 583 } 584 prev_bh = bh; 585 bh = bh->b_reqnext; 586 kfree(prev_bh); 587 } 588 kfree(tape->merge_bh); 589} 590 591static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 592{ 593 struct request *rq = HWGROUP(drive)->rq; 594 idetape_tape_t *tape = drive->driver_data; 595 unsigned long flags; 596 int error; 597 598 debug_log(DBG_PROCS, "Enter %s\n", __func__); 599 600 switch (uptodate) { 601 case 0: error = IDETAPE_ERROR_GENERAL; break; 602 case 1: error = 0; break; 603 default: error = uptodate; 604 } 605 rq->errors = error; 606 if (error) 607 tape->failed_pc = NULL; 608 609 if (!blk_special_request(rq)) { 610 ide_end_request(drive, uptodate, nr_sects); 611 return 0; 612 } 613 614 spin_lock_irqsave(&tape->lock, flags); 615 616 ide_end_drive_cmd(drive, 0, 0); 617 618 spin_unlock_irqrestore(&tape->lock, flags); 619 return 0; 620} 621 622static ide_startstop_t ide_tape_callback(ide_drive_t *drive) 623{ 624 idetape_tape_t *tape = drive->driver_data; 625 struct ide_atapi_pc *pc = tape->pc; 626 int uptodate = pc->error ? 0 : 1; 627 628 debug_log(DBG_PROCS, "Enter %s\n", __func__); 629 630 if (pc->c[0] == REQUEST_SENSE) { 631 if (uptodate) 632 idetape_analyze_error(drive, pc->buf); 633 else 634 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 635 "itself - Aborting request!\n"); 636 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 637 struct request *rq = drive->hwif->hwgroup->rq; 638 int blocks = pc->xferred / tape->blk_size; 639 640 tape->avg_size += blocks * tape->blk_size; 641 642 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 643 tape->avg_speed = tape->avg_size * HZ / 644 (jiffies - tape->avg_time) / 1024; 645 tape->avg_size = 0; 646 tape->avg_time = jiffies; 647 } 648 649 tape->first_frame += blocks; 650 rq->current_nr_sectors -= blocks; 651 652 if (pc->error) 653 uptodate = pc->error; 654 } else if (pc->c[0] == READ_POSITION && uptodate) { 655 u8 *readpos = tape->pc->buf; 656 657 debug_log(DBG_SENSE, "BOP - %s\n", 658 (readpos[0] & 0x80) ? "Yes" : "No"); 659 debug_log(DBG_SENSE, "EOP - %s\n", 660 (readpos[0] & 0x40) ? "Yes" : "No"); 661 662 if (readpos[0] & 0x4) { 663 printk(KERN_INFO "ide-tape: Block location is unknown" 664 "to the tape\n"); 665 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags); 666 uptodate = 0; 667 } else { 668 debug_log(DBG_SENSE, "Block Location - %u\n", 669 be32_to_cpu(*(u32 *)&readpos[4])); 670 671 tape->partition = readpos[1]; 672 tape->first_frame = be32_to_cpu(*(u32 *)&readpos[4]); 673 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags); 674 } 675 } 676 677 idetape_end_request(drive, uptodate, 0); 678 679 return ide_stopped; 680} 681 682static void idetape_init_pc(struct ide_atapi_pc *pc) 683{ 684 memset(pc->c, 0, 12); 685 pc->retries = 0; 686 pc->flags = 0; 687 pc->req_xfer = 0; 688 pc->buf = pc->pc_buf; 689 pc->buf_size = IDETAPE_PC_BUFFER_SIZE; 690 pc->bh = NULL; 691 pc->b_data = NULL; 692 pc->idetape_callback = ide_tape_callback; 693} 694 695static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc) 696{ 697 idetape_init_pc(pc); 698 pc->c[0] = REQUEST_SENSE; 699 pc->c[4] = 20; 700 pc->req_xfer = 20; 701} 702 703static void idetape_init_rq(struct request *rq, u8 cmd) 704{ 705 blk_rq_init(NULL, rq); 706 rq->cmd_type = REQ_TYPE_SPECIAL; 707 rq->cmd[0] = cmd; 708} 709 710/* 711 * Generate a new packet command request in front of the request queue, before 712 * the current request, so that it will be processed immediately, on the next 713 * pass through the driver. The function below is called from the request 714 * handling part of the driver (the "bottom" part). Safe storage for the request 715 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that. 716 * 717 * Memory for those requests is pre-allocated at initialization time, and is 718 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for 719 * the maximum possible number of inter-dependent packet commands. 720 * 721 * The higher level of the driver - The ioctl handler and the character device 722 * handling functions should queue request to the lower level part and wait for 723 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail. 724 */ 725static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc, 726 struct request *rq) 727{ 728 struct ide_tape_obj *tape = drive->driver_data; 729 730 idetape_init_rq(rq, REQ_IDETAPE_PC1); 731 rq->cmd_flags |= REQ_PREEMPT; 732 rq->buffer = (char *) pc; 733 rq->rq_disk = tape->disk; 734 ide_do_drive_cmd(drive, rq); 735} 736 737/* 738 * idetape_retry_pc is called when an error was detected during the 739 * last packet command. We queue a request sense packet command in 740 * the head of the request list. 741 */ 742static void idetape_retry_pc(ide_drive_t *drive) 743{ 744 idetape_tape_t *tape = drive->driver_data; 745 struct ide_atapi_pc *pc; 746 struct request *rq; 747 748 (void)ide_read_error(drive); 749 pc = idetape_next_pc_storage(drive); 750 rq = idetape_next_rq_storage(drive); 751 idetape_create_request_sense_cmd(pc); 752 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 753 idetape_queue_pc_head(drive, pc, rq); 754} 755 756/* 757 * Postpone the current request so that ide.c will be able to service requests 758 * from another device on the same hwgroup while we are polling for DSC. 759 */ 760static void idetape_postpone_request(ide_drive_t *drive) 761{ 762 idetape_tape_t *tape = drive->driver_data; 763 764 debug_log(DBG_PROCS, "Enter %s\n", __func__); 765 766 tape->postponed_rq = HWGROUP(drive)->rq; 767 ide_stall_queue(drive, tape->dsc_poll_freq); 768} 769 770typedef void idetape_io_buf(ide_drive_t *, struct ide_atapi_pc *, unsigned int); 771 772/* 773 * This is the usual interrupt handler which will be called during a packet 774 * command. We will transfer some of the data (as requested by the drive) and 775 * will re-point interrupt handler to us. When data transfer is finished, we 776 * will act according to the algorithm described before 777 * idetape_issue_pc. 778 */ 779static ide_startstop_t idetape_pc_intr(ide_drive_t *drive) 780{ 781 ide_hwif_t *hwif = drive->hwif; 782 idetape_tape_t *tape = drive->driver_data; 783 struct ide_atapi_pc *pc = tape->pc; 784 xfer_func_t *xferfunc; 785 idetape_io_buf *iobuf; 786 unsigned int temp; 787 u16 bcount; 788 u8 stat, ireason; 789 790 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__); 791 792 /* Clear the interrupt */ 793 stat = ide_read_status(drive); 794 795 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 796 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) { 797 pc->flags |= PC_FLAG_DMA_ERROR; 798 } else { 799 pc->xferred = pc->req_xfer; 800 idetape_update_buffers(pc); 801 } 802 debug_log(DBG_PROCS, "DMA finished\n"); 803 804 } 805 806 /* No more interrupts */ 807 if ((stat & DRQ_STAT) == 0) { 808 debug_log(DBG_SENSE, "Packet command completed, %d bytes" 809 " transferred\n", pc->xferred); 810 811 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 812 local_irq_enable_in_hardirq(); 813 814 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE) 815 stat &= ~ERR_STAT; 816 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) { 817 /* Error detected */ 818 debug_log(DBG_ERR, "%s: I/O error\n", tape->name); 819 820 if (pc->c[0] == REQUEST_SENSE) { 821 printk(KERN_ERR "%s: I/O error in request sense" 822 " command\n", drive->name); 823 return ide_do_reset(drive); 824 } 825 debug_log(DBG_ERR, "[cmd %x]: check condition\n", 826 pc->c[0]); 827 828 /* Retry operation */ 829 idetape_retry_pc(drive); 830 return ide_stopped; 831 } 832 pc->error = 0; 833 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && 834 (stat & SEEK_STAT) == 0) { 835 /* Media access command */ 836 tape->dsc_polling_start = jiffies; 837 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 838 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 839 /* Allow ide.c to handle other requests */ 840 idetape_postpone_request(drive); 841 return ide_stopped; 842 } 843 if (tape->failed_pc == pc) 844 tape->failed_pc = NULL; 845 /* Command finished - Call the callback function */ 846 return pc->idetape_callback(drive); 847 } 848 849 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 850 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 851 printk(KERN_ERR "%s: The device wants to issue more interrupts " 852 "in DMA mode\n", drive->name); 853 ide_dma_off(drive); 854 return ide_do_reset(drive); 855 } 856 /* Get the number of bytes to transfer on this interrupt. */ 857 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) | 858 hwif->INB(hwif->io_ports.lbam_addr); 859 860 ireason = hwif->INB(hwif->io_ports.nsect_addr); 861 862 if (ireason & CD) { 863 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__); 864 return ide_do_reset(drive); 865 } 866 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) { 867 /* Hopefully, we will never get here */ 868 printk(KERN_ERR "%s: We wanted to %s, but the device wants us " 869 "to %s!\n", drive->name, 870 (ireason & IO) ? "Write" : "Read", 871 (ireason & IO) ? "Read" : "Write"); 872 return ide_do_reset(drive); 873 } 874 if (!(pc->flags & PC_FLAG_WRITING)) { 875 /* Reading - Check that we have enough space */ 876 temp = pc->xferred + bcount; 877 if (temp > pc->req_xfer) { 878 if (temp > pc->buf_size) { 879 printk(KERN_ERR "%s: The device wants to send " 880 "us more data than expected - " 881 "discarding data\n", 882 drive->name); 883 ide_pad_transfer(drive, 0, bcount); 884 ide_set_handler(drive, &idetape_pc_intr, 885 IDETAPE_WAIT_CMD, NULL); 886 return ide_started; 887 } 888 debug_log(DBG_SENSE, "The device wants to send us more " 889 "data than expected - allowing transfer\n"); 890 } 891 iobuf = &idetape_input_buffers; 892 xferfunc = hwif->input_data; 893 } else { 894 iobuf = &idetape_output_buffers; 895 xferfunc = hwif->output_data; 896 } 897 898 if (pc->bh) 899 iobuf(drive, pc, bcount); 900 else 901 xferfunc(drive, NULL, pc->cur_pos, bcount); 902 903 /* Update the current position */ 904 pc->xferred += bcount; 905 pc->cur_pos += bcount; 906 907 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n", 908 pc->c[0], bcount); 909 910 /* And set the interrupt handler again */ 911 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 912 return ide_started; 913} 914 915/* 916 * Packet Command Interface 917 * 918 * The current Packet Command is available in tape->pc, and will not change 919 * until we finish handling it. Each packet command is associated with a 920 * callback function that will be called when the command is finished. 921 * 922 * The handling will be done in three stages: 923 * 924 * 1. idetape_issue_pc will send the packet command to the drive, and will set 925 * the interrupt handler to idetape_pc_intr. 926 * 927 * 2. On each interrupt, idetape_pc_intr will be called. This step will be 928 * repeated until the device signals us that no more interrupts will be issued. 929 * 930 * 3. ATAPI Tape media access commands have immediate status with a delayed 931 * process. In case of a successful initiation of a media access packet command, 932 * the DSC bit will be set when the actual execution of the command is finished. 933 * Since the tape drive will not issue an interrupt, we have to poll for this 934 * event. In this case, we define the request as "low priority request" by 935 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 936 * exit the driver. 937 * 938 * ide.c will then give higher priority to requests which originate from the 939 * other device, until will change rq_status to RQ_ACTIVE. 940 * 941 * 4. When the packet command is finished, it will be checked for errors. 942 * 943 * 5. In case an error was found, we queue a request sense packet command in 944 * front of the request queue and retry the operation up to 945 * IDETAPE_MAX_PC_RETRIES times. 946 * 947 * 6. In case no error was found, or we decided to give up and not to retry 948 * again, the callback function will be called and then we will handle the next 949 * request. 950 */ 951static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 952{ 953 ide_hwif_t *hwif = drive->hwif; 954 idetape_tape_t *tape = drive->driver_data; 955 struct ide_atapi_pc *pc = tape->pc; 956 int retries = 100; 957 ide_startstop_t startstop; 958 u8 ireason; 959 960 if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) { 961 printk(KERN_ERR "%s: Strange, packet command initiated yet " 962 "DRQ isn't asserted\n", drive->name); 963 return startstop; 964 } 965 ireason = hwif->INB(hwif->io_ports.nsect_addr); 966 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) { 967 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing " 968 "a packet command, retrying\n", drive->name); 969 udelay(100); 970 ireason = hwif->INB(hwif->io_ports.nsect_addr); 971 if (retries == 0) { 972 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing " 973 "a packet command, ignoring\n", 974 drive->name); 975 ireason |= CD; 976 ireason &= ~IO; 977 } 978 } 979 if ((ireason & CD) == 0 || (ireason & IO)) { 980 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing " 981 "a packet command\n", drive->name); 982 return ide_do_reset(drive); 983 } 984 /* Set the interrupt routine */ 985 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 986 987 /* Begin DMA, if necessary */ 988 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) 989 hwif->dma_ops->dma_start(drive); 990 991 /* Send the actual packet */ 992 hwif->output_data(drive, NULL, pc->c, 12); 993 994 return ide_started; 995} 996 997static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 998 struct ide_atapi_pc *pc) 999{ 1000 ide_hwif_t *hwif = drive->hwif; 1001 idetape_tape_t *tape = drive->driver_data; 1002 int dma_ok = 0; 1003 u16 bcount; 1004 1005 if (tape->pc->c[0] == REQUEST_SENSE && 1006 pc->c[0] == REQUEST_SENSE) { 1007 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 1008 "Two request sense in serial were issued\n"); 1009 } 1010 1011 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 1012 tape->failed_pc = pc; 1013 /* Set the current packet command */ 1014 tape->pc = pc; 1015 1016 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 1017 (pc->flags & PC_FLAG_ABORT)) { 1018 /* 1019 * We will "abort" retrying a packet command in case legitimate 1020 * error code was received (crossing a filemark, or end of the 1021 * media, for example). 1022 */ 1023 if (!(pc->flags & PC_FLAG_ABORT)) { 1024 if (!(pc->c[0] == TEST_UNIT_READY && 1025 tape->sense_key == 2 && tape->asc == 4 && 1026 (tape->ascq == 1 || tape->ascq == 8))) { 1027 printk(KERN_ERR "ide-tape: %s: I/O error, " 1028 "pc = %2x, key = %2x, " 1029 "asc = %2x, ascq = %2x\n", 1030 tape->name, pc->c[0], 1031 tape->sense_key, tape->asc, 1032 tape->ascq); 1033 } 1034 /* Giving up */ 1035 pc->error = IDETAPE_ERROR_GENERAL; 1036 } 1037 tape->failed_pc = NULL; 1038 return pc->idetape_callback(drive); 1039 } 1040 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 1041 1042 pc->retries++; 1043 /* We haven't transferred any data yet */ 1044 pc->xferred = 0; 1045 pc->cur_pos = pc->buf; 1046 /* Request to transfer the entire buffer at once */ 1047 bcount = pc->req_xfer; 1048 1049 if (pc->flags & PC_FLAG_DMA_ERROR) { 1050 pc->flags &= ~PC_FLAG_DMA_ERROR; 1051 ide_dma_off(drive); 1052 } 1053 if ((pc->flags & PC_FLAG_DMA_RECOMMENDED) && drive->using_dma) 1054 dma_ok = !hwif->dma_ops->dma_setup(drive); 1055 1056 ide_pktcmd_tf_load(drive, IDE_TFLAG_OUT_DEVICE, bcount, dma_ok); 1057 1058 if (dma_ok) 1059 /* Will begin DMA later */ 1060 pc->flags |= PC_FLAG_DMA_IN_PROGRESS; 1061 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags)) { 1062 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc, 1063 IDETAPE_WAIT_CMD, NULL); 1064 return ide_started; 1065 } else { 1066 ide_execute_pkt_cmd(drive); 1067 return idetape_transfer_pc(drive); 1068 } 1069} 1070 1071/* A mode sense command is used to "sense" tape parameters. */ 1072static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 1073{ 1074 idetape_init_pc(pc); 1075 pc->c[0] = MODE_SENSE; 1076 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 1077 /* DBD = 1 - Don't return block descriptors */ 1078 pc->c[1] = 8; 1079 pc->c[2] = page_code; 1080 /* 1081 * Changed pc->c[3] to 0 (255 will at best return unused info). 1082 * 1083 * For SCSI this byte is defined as subpage instead of high byte 1084 * of length and some IDE drives seem to interpret it this way 1085 * and return an error when 255 is used. 1086 */ 1087 pc->c[3] = 0; 1088 /* We will just discard data in that case */ 1089 pc->c[4] = 255; 1090 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 1091 pc->req_xfer = 12; 1092 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 1093 pc->req_xfer = 24; 1094 else 1095 pc->req_xfer = 50; 1096} 1097 1098static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 1099{ 1100 idetape_tape_t *tape = drive->driver_data; 1101 struct ide_atapi_pc *pc = tape->pc; 1102 u8 stat; 1103 1104 stat = ide_read_status(drive); 1105 1106 if (stat & SEEK_STAT) { 1107 if (stat & ERR_STAT) { 1108 /* Error detected */ 1109 if (pc->c[0] != TEST_UNIT_READY) 1110 printk(KERN_ERR "ide-tape: %s: I/O error, ", 1111 tape->name); 1112 /* Retry operation */ 1113 idetape_retry_pc(drive); 1114 return ide_stopped; 1115 } 1116 pc->error = 0; 1117 if (tape->failed_pc == pc) 1118 tape->failed_pc = NULL; 1119 } else { 1120 pc->error = IDETAPE_ERROR_GENERAL; 1121 tape->failed_pc = NULL; 1122 } 1123 return pc->idetape_callback(drive); 1124} 1125 1126static void idetape_create_read_cmd(idetape_tape_t *tape, 1127 struct ide_atapi_pc *pc, 1128 unsigned int length, struct idetape_bh *bh) 1129{ 1130 idetape_init_pc(pc); 1131 pc->c[0] = READ_6; 1132 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1133 pc->c[1] = 1; 1134 pc->bh = bh; 1135 atomic_set(&bh->b_count, 0); 1136 pc->buf = NULL; 1137 pc->buf_size = length * tape->blk_size; 1138 pc->req_xfer = pc->buf_size; 1139 if (pc->req_xfer == tape->buffer_size) 1140 pc->flags |= PC_FLAG_DMA_RECOMMENDED; 1141} 1142 1143static void idetape_create_write_cmd(idetape_tape_t *tape, 1144 struct ide_atapi_pc *pc, 1145 unsigned int length, struct idetape_bh *bh) 1146{ 1147 idetape_init_pc(pc); 1148 pc->c[0] = WRITE_6; 1149 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1150 pc->c[1] = 1; 1151 pc->flags |= PC_FLAG_WRITING; 1152 pc->bh = bh; 1153 pc->b_data = bh->b_data; 1154 pc->b_count = atomic_read(&bh->b_count); 1155 pc->buf = NULL; 1156 pc->buf_size = length * tape->blk_size; 1157 pc->req_xfer = pc->buf_size; 1158 if (pc->req_xfer == tape->buffer_size) 1159 pc->flags |= PC_FLAG_DMA_RECOMMENDED; 1160} 1161 1162static ide_startstop_t idetape_do_request(ide_drive_t *drive, 1163 struct request *rq, sector_t block) 1164{ 1165 idetape_tape_t *tape = drive->driver_data; 1166 struct ide_atapi_pc *pc = NULL; 1167 struct request *postponed_rq = tape->postponed_rq; 1168 u8 stat; 1169 1170 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld," 1171 " current_nr_sectors: %d\n", 1172 rq->sector, rq->nr_sectors, rq->current_nr_sectors); 1173 1174 if (!blk_special_request(rq)) { 1175 /* We do not support buffer cache originated requests. */ 1176 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 1177 "request queue (%d)\n", drive->name, rq->cmd_type); 1178 ide_end_request(drive, 0, 0); 1179 return ide_stopped; 1180 } 1181 1182 /* Retry a failed packet command */ 1183 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) 1184 return idetape_issue_pc(drive, tape->failed_pc); 1185 1186 if (postponed_rq != NULL) 1187 if (rq != postponed_rq) { 1188 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 1189 "Two DSC requests were queued\n"); 1190 idetape_end_request(drive, 0, 0); 1191 return ide_stopped; 1192 } 1193 1194 tape->postponed_rq = NULL; 1195 1196 /* 1197 * If the tape is still busy, postpone our request and service 1198 * the other device meanwhile. 1199 */ 1200 stat = ide_read_status(drive); 1201 1202 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2)) 1203 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1204 1205 if (drive->post_reset == 1) { 1206 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1207 drive->post_reset = 0; 1208 } 1209 1210 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) && 1211 (stat & SEEK_STAT) == 0) { 1212 if (postponed_rq == NULL) { 1213 tape->dsc_polling_start = jiffies; 1214 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 1215 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 1216 } else if (time_after(jiffies, tape->dsc_timeout)) { 1217 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 1218 tape->name); 1219 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1220 idetape_media_access_finished(drive); 1221 return ide_stopped; 1222 } else { 1223 return ide_do_reset(drive); 1224 } 1225 } else if (time_after(jiffies, 1226 tape->dsc_polling_start + 1227 IDETAPE_DSC_MA_THRESHOLD)) 1228 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 1229 idetape_postpone_request(drive); 1230 return ide_stopped; 1231 } 1232 if (rq->cmd[0] & REQ_IDETAPE_READ) { 1233 pc = idetape_next_pc_storage(drive); 1234 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, 1235 (struct idetape_bh *)rq->special); 1236 goto out; 1237 } 1238 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 1239 pc = idetape_next_pc_storage(drive); 1240 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, 1241 (struct idetape_bh *)rq->special); 1242 goto out; 1243 } 1244 if (rq->cmd[0] & REQ_IDETAPE_PC1) { 1245 pc = (struct ide_atapi_pc *) rq->buffer; 1246 rq->cmd[0] &= ~(REQ_IDETAPE_PC1); 1247 rq->cmd[0] |= REQ_IDETAPE_PC2; 1248 goto out; 1249 } 1250 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1251 idetape_media_access_finished(drive); 1252 return ide_stopped; 1253 } 1254 BUG(); 1255out: 1256 return idetape_issue_pc(drive, pc); 1257} 1258 1259/* 1260 * The function below uses __get_free_pages to allocate a data buffer of size 1261 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 1262 * much as possible. 1263 * 1264 * It returns a pointer to the newly allocated buffer, or NULL in case of 1265 * failure. 1266 */ 1267static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 1268 int full, int clear) 1269{ 1270 struct idetape_bh *prev_bh, *bh, *merge_bh; 1271 int pages = tape->pages_per_buffer; 1272 unsigned int order, b_allocd; 1273 char *b_data = NULL; 1274 1275 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1276 bh = merge_bh; 1277 if (bh == NULL) 1278 goto abort; 1279 1280 order = fls(pages) - 1; 1281 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1282 if (!bh->b_data) 1283 goto abort; 1284 b_allocd = (1 << order) * PAGE_SIZE; 1285 pages &= (order-1); 1286 1287 if (clear) 1288 memset(bh->b_data, 0, b_allocd); 1289 bh->b_reqnext = NULL; 1290 bh->b_size = b_allocd; 1291 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1292 1293 while (pages) { 1294 order = fls(pages) - 1; 1295 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1296 if (!b_data) 1297 goto abort; 1298 b_allocd = (1 << order) * PAGE_SIZE; 1299 1300 if (clear) 1301 memset(b_data, 0, b_allocd); 1302 1303 /* newly allocated page frames below buffer header or ...*/ 1304 if (bh->b_data == b_data + b_allocd) { 1305 bh->b_size += b_allocd; 1306 bh->b_data -= b_allocd; 1307 if (full) 1308 atomic_add(b_allocd, &bh->b_count); 1309 continue; 1310 } 1311 /* they are above the header */ 1312 if (b_data == bh->b_data + bh->b_size) { 1313 bh->b_size += b_allocd; 1314 if (full) 1315 atomic_add(b_allocd, &bh->b_count); 1316 continue; 1317 } 1318 prev_bh = bh; 1319 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1320 if (!bh) { 1321 free_pages((unsigned long) b_data, order); 1322 goto abort; 1323 } 1324 bh->b_reqnext = NULL; 1325 bh->b_data = b_data; 1326 bh->b_size = b_allocd; 1327 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1328 prev_bh->b_reqnext = bh; 1329 1330 pages &= (order-1); 1331 } 1332 1333 bh->b_size -= tape->excess_bh_size; 1334 if (full) 1335 atomic_sub(tape->excess_bh_size, &bh->b_count); 1336 return merge_bh; 1337abort: 1338 ide_tape_kfree_buffer(tape); 1339 return NULL; 1340} 1341 1342static int idetape_copy_stage_from_user(idetape_tape_t *tape, 1343 const char __user *buf, int n) 1344{ 1345 struct idetape_bh *bh = tape->bh; 1346 int count; 1347 int ret = 0; 1348 1349 while (n) { 1350 if (bh == NULL) { 1351 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1352 __func__); 1353 return 1; 1354 } 1355 count = min((unsigned int) 1356 (bh->b_size - atomic_read(&bh->b_count)), 1357 (unsigned int)n); 1358 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 1359 count)) 1360 ret = 1; 1361 n -= count; 1362 atomic_add(count, &bh->b_count); 1363 buf += count; 1364 if (atomic_read(&bh->b_count) == bh->b_size) { 1365 bh = bh->b_reqnext; 1366 if (bh) 1367 atomic_set(&bh->b_count, 0); 1368 } 1369 } 1370 tape->bh = bh; 1371 return ret; 1372} 1373 1374static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1375 int n) 1376{ 1377 struct idetape_bh *bh = tape->bh; 1378 int count; 1379 int ret = 0; 1380 1381 while (n) { 1382 if (bh == NULL) { 1383 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1384 __func__); 1385 return 1; 1386 } 1387 count = min(tape->b_count, n); 1388 if (copy_to_user(buf, tape->b_data, count)) 1389 ret = 1; 1390 n -= count; 1391 tape->b_data += count; 1392 tape->b_count -= count; 1393 buf += count; 1394 if (!tape->b_count) { 1395 bh = bh->b_reqnext; 1396 tape->bh = bh; 1397 if (bh) { 1398 tape->b_data = bh->b_data; 1399 tape->b_count = atomic_read(&bh->b_count); 1400 } 1401 } 1402 } 1403 return ret; 1404} 1405 1406static void idetape_init_merge_buffer(idetape_tape_t *tape) 1407{ 1408 struct idetape_bh *bh = tape->merge_bh; 1409 tape->bh = tape->merge_bh; 1410 1411 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1412 atomic_set(&bh->b_count, 0); 1413 else { 1414 tape->b_data = bh->b_data; 1415 tape->b_count = atomic_read(&bh->b_count); 1416 } 1417} 1418 1419/* 1420 * Write a filemark if write_filemark=1. Flush the device buffers without 1421 * writing a filemark otherwise. 1422 */ 1423static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1424 struct ide_atapi_pc *pc, int write_filemark) 1425{ 1426 idetape_init_pc(pc); 1427 pc->c[0] = WRITE_FILEMARKS; 1428 pc->c[4] = write_filemark; 1429 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1430} 1431 1432static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc) 1433{ 1434 idetape_init_pc(pc); 1435 pc->c[0] = TEST_UNIT_READY; 1436} 1437 1438/* 1439 * We add a special packet command request to the tail of the request queue, and 1440 * wait for it to be serviced. This is not to be called from within the request 1441 * handling part of the driver! We allocate here data on the stack and it is 1442 * valid until the request is finished. This is not the case for the bottom part 1443 * of the driver, where we are always leaving the functions to wait for an 1444 * interrupt or a timer event. 1445 * 1446 * From the bottom part of the driver, we should allocate safe memory using 1447 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request 1448 * to the request list without waiting for it to be serviced! In that case, we 1449 * usually use idetape_queue_pc_head(). 1450 */ 1451static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc) 1452{ 1453 struct ide_tape_obj *tape = drive->driver_data; 1454 struct request *rq; 1455 int error; 1456 1457 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1458 rq->cmd_type = REQ_TYPE_SPECIAL; 1459 rq->cmd[0] = REQ_IDETAPE_PC1; 1460 rq->buffer = (char *)pc; 1461 error = blk_execute_rq(drive->queue, tape->disk, rq, 0); 1462 blk_put_request(rq); 1463 return error; 1464} 1465 1466static void idetape_create_load_unload_cmd(ide_drive_t *drive, 1467 struct ide_atapi_pc *pc, int cmd) 1468{ 1469 idetape_init_pc(pc); 1470 pc->c[0] = START_STOP; 1471 pc->c[4] = cmd; 1472 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1473} 1474 1475static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1476{ 1477 idetape_tape_t *tape = drive->driver_data; 1478 struct ide_atapi_pc pc; 1479 int load_attempted = 0; 1480 1481 /* Wait for the tape to become ready */ 1482 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 1483 timeout += jiffies; 1484 while (time_before(jiffies, timeout)) { 1485 idetape_create_test_unit_ready_cmd(&pc); 1486 if (!idetape_queue_pc_tail(drive, &pc)) 1487 return 0; 1488 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1489 || (tape->asc == 0x3A)) { 1490 /* no media */ 1491 if (load_attempted) 1492 return -ENOMEDIUM; 1493 idetape_create_load_unload_cmd(drive, &pc, 1494 IDETAPE_LU_LOAD_MASK); 1495 idetape_queue_pc_tail(drive, &pc); 1496 load_attempted = 1; 1497 /* not about to be ready */ 1498 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1499 (tape->ascq == 1 || tape->ascq == 8))) 1500 return -EIO; 1501 msleep(100); 1502 } 1503 return -EIO; 1504} 1505 1506static int idetape_flush_tape_buffers(ide_drive_t *drive) 1507{ 1508 struct ide_atapi_pc pc; 1509 int rc; 1510 1511 idetape_create_write_filemark_cmd(drive, &pc, 0); 1512 rc = idetape_queue_pc_tail(drive, &pc); 1513 if (rc) 1514 return rc; 1515 idetape_wait_ready(drive, 60 * 5 * HZ); 1516 return 0; 1517} 1518 1519static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1520{ 1521 idetape_init_pc(pc); 1522 pc->c[0] = READ_POSITION; 1523 pc->req_xfer = 20; 1524} 1525 1526static int idetape_read_position(ide_drive_t *drive) 1527{ 1528 idetape_tape_t *tape = drive->driver_data; 1529 struct ide_atapi_pc pc; 1530 int position; 1531 1532 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1533 1534 idetape_create_read_position_cmd(&pc); 1535 if (idetape_queue_pc_tail(drive, &pc)) 1536 return -1; 1537 position = tape->first_frame; 1538 return position; 1539} 1540 1541static void idetape_create_locate_cmd(ide_drive_t *drive, 1542 struct ide_atapi_pc *pc, 1543 unsigned int block, u8 partition, int skip) 1544{ 1545 idetape_init_pc(pc); 1546 pc->c[0] = POSITION_TO_ELEMENT; 1547 pc->c[1] = 2; 1548 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1549 pc->c[8] = partition; 1550 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1551} 1552 1553static int idetape_create_prevent_cmd(ide_drive_t *drive, 1554 struct ide_atapi_pc *pc, int prevent) 1555{ 1556 idetape_tape_t *tape = drive->driver_data; 1557 1558 /* device supports locking according to capabilities page */ 1559 if (!(tape->caps[6] & 0x01)) 1560 return 0; 1561 1562 idetape_init_pc(pc); 1563 pc->c[0] = ALLOW_MEDIUM_REMOVAL; 1564 pc->c[4] = prevent; 1565 return 1; 1566} 1567 1568static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1569{ 1570 idetape_tape_t *tape = drive->driver_data; 1571 1572 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1573 return; 1574 1575 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags); 1576 tape->merge_bh_size = 0; 1577 if (tape->merge_bh != NULL) { 1578 ide_tape_kfree_buffer(tape); 1579 tape->merge_bh = NULL; 1580 } 1581 1582 tape->chrdev_dir = IDETAPE_DIR_NONE; 1583} 1584 1585/* 1586 * Position the tape to the requested block using the LOCATE packet command. 1587 * A READ POSITION command is then issued to check where we are positioned. Like 1588 * all higher level operations, we queue the commands at the tail of the request 1589 * queue and wait for their completion. 1590 */ 1591static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1592 u8 partition, int skip) 1593{ 1594 idetape_tape_t *tape = drive->driver_data; 1595 int retval; 1596 struct ide_atapi_pc pc; 1597 1598 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1599 __ide_tape_discard_merge_buffer(drive); 1600 idetape_wait_ready(drive, 60 * 5 * HZ); 1601 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1602 retval = idetape_queue_pc_tail(drive, &pc); 1603 if (retval) 1604 return (retval); 1605 1606 idetape_create_read_position_cmd(&pc); 1607 return (idetape_queue_pc_tail(drive, &pc)); 1608} 1609 1610static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1611 int restore_position) 1612{ 1613 idetape_tape_t *tape = drive->driver_data; 1614 int seek, position; 1615 1616 __ide_tape_discard_merge_buffer(drive); 1617 if (restore_position) { 1618 position = idetape_read_position(drive); 1619 seek = position > 0 ? position : 0; 1620 if (idetape_position_tape(drive, seek, 0, 0)) { 1621 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1622 " %s\n", tape->name, __func__); 1623 return; 1624 } 1625 } 1626} 1627 1628/* 1629 * Generate a read/write request for the block device interface and wait for it 1630 * to be serviced. 1631 */ 1632static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1633 struct idetape_bh *bh) 1634{ 1635 idetape_tape_t *tape = drive->driver_data; 1636 struct request *rq; 1637 int ret, errors; 1638 1639 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1640 1641 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1642 rq->cmd_type = REQ_TYPE_SPECIAL; 1643 rq->cmd[0] = cmd; 1644 rq->rq_disk = tape->disk; 1645 rq->special = (void *)bh; 1646 rq->sector = tape->first_frame; 1647 rq->nr_sectors = blocks; 1648 rq->current_nr_sectors = blocks; 1649 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1650 1651 errors = rq->errors; 1652 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1653 blk_put_request(rq); 1654 1655 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1656 return 0; 1657 1658 if (tape->merge_bh) 1659 idetape_init_merge_buffer(tape); 1660 if (errors == IDETAPE_ERROR_GENERAL) 1661 return -EIO; 1662 return ret; 1663} 1664 1665static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1666{ 1667 idetape_init_pc(pc); 1668 pc->c[0] = INQUIRY; 1669 pc->c[4] = 254; 1670 pc->req_xfer = 254; 1671} 1672 1673static void idetape_create_rewind_cmd(ide_drive_t *drive, 1674 struct ide_atapi_pc *pc) 1675{ 1676 idetape_init_pc(pc); 1677 pc->c[0] = REZERO_UNIT; 1678 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1679} 1680 1681static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1682{ 1683 idetape_init_pc(pc); 1684 pc->c[0] = ERASE; 1685 pc->c[1] = 1; 1686 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1687} 1688 1689static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1690{ 1691 idetape_init_pc(pc); 1692 pc->c[0] = SPACE; 1693 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1694 pc->c[1] = cmd; 1695 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1696} 1697 1698/* Queue up a character device originated write request. */ 1699static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1700{ 1701 idetape_tape_t *tape = drive->driver_data; 1702 1703 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1704 1705 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1706 blocks, tape->merge_bh); 1707} 1708 1709static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1710{ 1711 idetape_tape_t *tape = drive->driver_data; 1712 int blocks, min; 1713 struct idetape_bh *bh; 1714 1715 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1716 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1717 " but we are not writing.\n"); 1718 return; 1719 } 1720 if (tape->merge_bh_size > tape->buffer_size) { 1721 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1722 tape->merge_bh_size = tape->buffer_size; 1723 } 1724 if (tape->merge_bh_size) { 1725 blocks = tape->merge_bh_size / tape->blk_size; 1726 if (tape->merge_bh_size % tape->blk_size) { 1727 unsigned int i; 1728 1729 blocks++; 1730 i = tape->blk_size - tape->merge_bh_size % 1731 tape->blk_size; 1732 bh = tape->bh->b_reqnext; 1733 while (bh) { 1734 atomic_set(&bh->b_count, 0); 1735 bh = bh->b_reqnext; 1736 } 1737 bh = tape->bh; 1738 while (i) { 1739 if (bh == NULL) { 1740 printk(KERN_INFO "ide-tape: bug," 1741 " bh NULL\n"); 1742 break; 1743 } 1744 min = min(i, (unsigned int)(bh->b_size - 1745 atomic_read(&bh->b_count))); 1746 memset(bh->b_data + atomic_read(&bh->b_count), 1747 0, min); 1748 atomic_add(min, &bh->b_count); 1749 i -= min; 1750 bh = bh->b_reqnext; 1751 } 1752 } 1753 (void) idetape_add_chrdev_write_request(drive, blocks); 1754 tape->merge_bh_size = 0; 1755 } 1756 if (tape->merge_bh != NULL) { 1757 ide_tape_kfree_buffer(tape); 1758 tape->merge_bh = NULL; 1759 } 1760 tape->chrdev_dir = IDETAPE_DIR_NONE; 1761} 1762 1763static int idetape_init_read(ide_drive_t *drive) 1764{ 1765 idetape_tape_t *tape = drive->driver_data; 1766 int bytes_read; 1767 1768 /* Initialize read operation */ 1769 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1770 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1771 ide_tape_flush_merge_buffer(drive); 1772 idetape_flush_tape_buffers(drive); 1773 } 1774 if (tape->merge_bh || tape->merge_bh_size) { 1775 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1776 " 0 now\n"); 1777 tape->merge_bh_size = 0; 1778 } 1779 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1780 if (!tape->merge_bh) 1781 return -ENOMEM; 1782 tape->chrdev_dir = IDETAPE_DIR_READ; 1783 1784 /* 1785 * Issue a read 0 command to ensure that DSC handshake is 1786 * switched from completion mode to buffer available mode. 1787 * No point in issuing this if DSC overlap isn't supported, some 1788 * drives (Seagate STT3401A) will return an error. 1789 */ 1790 if (drive->dsc_overlap) { 1791 bytes_read = idetape_queue_rw_tail(drive, 1792 REQ_IDETAPE_READ, 0, 1793 tape->merge_bh); 1794 if (bytes_read < 0) { 1795 ide_tape_kfree_buffer(tape); 1796 tape->merge_bh = NULL; 1797 tape->chrdev_dir = IDETAPE_DIR_NONE; 1798 return bytes_read; 1799 } 1800 } 1801 } 1802 1803 return 0; 1804} 1805 1806/* called from idetape_chrdev_read() to service a chrdev read request. */ 1807static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1808{ 1809 idetape_tape_t *tape = drive->driver_data; 1810 1811 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1812 1813 /* If we are at a filemark, return a read length of 0 */ 1814 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1815 return 0; 1816 1817 idetape_init_read(drive); 1818 1819 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1820 tape->merge_bh); 1821} 1822 1823static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1824{ 1825 idetape_tape_t *tape = drive->driver_data; 1826 struct idetape_bh *bh; 1827 int blocks; 1828 1829 while (bcount) { 1830 unsigned int count; 1831 1832 bh = tape->merge_bh; 1833 count = min(tape->buffer_size, bcount); 1834 bcount -= count; 1835 blocks = count / tape->blk_size; 1836 while (count) { 1837 atomic_set(&bh->b_count, 1838 min(count, (unsigned int)bh->b_size)); 1839 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1840 count -= atomic_read(&bh->b_count); 1841 bh = bh->b_reqnext; 1842 } 1843 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1844 tape->merge_bh); 1845 } 1846} 1847 1848/* 1849 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1850 * currently support only one partition. 1851 */ 1852static int idetape_rewind_tape(ide_drive_t *drive) 1853{ 1854 int retval; 1855 struct ide_atapi_pc pc; 1856 idetape_tape_t *tape; 1857 tape = drive->driver_data; 1858 1859 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1860 1861 idetape_create_rewind_cmd(drive, &pc); 1862 retval = idetape_queue_pc_tail(drive, &pc); 1863 if (retval) 1864 return retval; 1865 1866 idetape_create_read_position_cmd(&pc); 1867 retval = idetape_queue_pc_tail(drive, &pc); 1868 if (retval) 1869 return retval; 1870 return 0; 1871} 1872 1873/* mtio.h compatible commands should be issued to the chrdev interface. */ 1874static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1875 unsigned long arg) 1876{ 1877 idetape_tape_t *tape = drive->driver_data; 1878 void __user *argp = (void __user *)arg; 1879 1880 struct idetape_config { 1881 int dsc_rw_frequency; 1882 int dsc_media_access_frequency; 1883 int nr_stages; 1884 } config; 1885 1886 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1887 1888 switch (cmd) { 1889 case 0x0340: 1890 if (copy_from_user(&config, argp, sizeof(config))) 1891 return -EFAULT; 1892 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1893 break; 1894 case 0x0350: 1895 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1896 config.nr_stages = 1; 1897 if (copy_to_user(argp, &config, sizeof(config))) 1898 return -EFAULT; 1899 break; 1900 default: 1901 return -EIO; 1902 } 1903 return 0; 1904} 1905 1906static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1907 int mt_count) 1908{ 1909 idetape_tape_t *tape = drive->driver_data; 1910 struct ide_atapi_pc pc; 1911 int retval, count = 0; 1912 int sprev = !!(tape->caps[4] & 0x20); 1913 1914 if (mt_count == 0) 1915 return 0; 1916 if (MTBSF == mt_op || MTBSFM == mt_op) { 1917 if (!sprev) 1918 return -EIO; 1919 mt_count = -mt_count; 1920 } 1921 1922 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1923 tape->merge_bh_size = 0; 1924 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1925 ++count; 1926 ide_tape_discard_merge_buffer(drive, 0); 1927 } 1928 1929 switch (mt_op) { 1930 case MTFSF: 1931 case MTBSF: 1932 idetape_create_space_cmd(&pc, mt_count - count, 1933 IDETAPE_SPACE_OVER_FILEMARK); 1934 return idetape_queue_pc_tail(drive, &pc); 1935 case MTFSFM: 1936 case MTBSFM: 1937 if (!sprev) 1938 return -EIO; 1939 retval = idetape_space_over_filemarks(drive, MTFSF, 1940 mt_count - count); 1941 if (retval) 1942 return retval; 1943 count = (MTBSFM == mt_op ? 1 : -1); 1944 return idetape_space_over_filemarks(drive, MTFSF, count); 1945 default: 1946 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1947 mt_op); 1948 return -EIO; 1949 } 1950} 1951 1952/* 1953 * Our character device read / write functions. 1954 * 1955 * The tape is optimized to maximize throughput when it is transferring an 1956 * integral number of the "continuous transfer limit", which is a parameter of 1957 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1958 * 1959 * As of version 1.3 of the driver, the character device provides an abstract 1960 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1961 * same backup/restore procedure is supported. The driver will internally 1962 * convert the requests to the recommended transfer unit, so that an unmatch 1963 * between the user's block size to the recommended size will only result in a 1964 * (slightly) increased driver overhead, but will no longer hit performance. 1965 * This is not applicable to Onstream. 1966 */ 1967static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1968 size_t count, loff_t *ppos) 1969{ 1970 struct ide_tape_obj *tape = ide_tape_f(file); 1971 ide_drive_t *drive = tape->drive; 1972 ssize_t bytes_read, temp, actually_read = 0, rc; 1973 ssize_t ret = 0; 1974 u16 ctl = *(u16 *)&tape->caps[12]; 1975 1976 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1977 1978 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1979 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags)) 1980 if (count > tape->blk_size && 1981 (count % tape->blk_size) == 0) 1982 tape->user_bs_factor = count / tape->blk_size; 1983 } 1984 rc = idetape_init_read(drive); 1985 if (rc < 0) 1986 return rc; 1987 if (count == 0) 1988 return (0); 1989 if (tape->merge_bh_size) { 1990 actually_read = min((unsigned int)(tape->merge_bh_size), 1991 (unsigned int)count); 1992 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1993 ret = -EFAULT; 1994 buf += actually_read; 1995 tape->merge_bh_size -= actually_read; 1996 count -= actually_read; 1997 } 1998 while (count >= tape->buffer_size) { 1999 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2000 if (bytes_read <= 0) 2001 goto finish; 2002 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 2003 ret = -EFAULT; 2004 buf += bytes_read; 2005 count -= bytes_read; 2006 actually_read += bytes_read; 2007 } 2008 if (count) { 2009 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2010 if (bytes_read <= 0) 2011 goto finish; 2012 temp = min((unsigned long)count, (unsigned long)bytes_read); 2013 if (idetape_copy_stage_to_user(tape, buf, temp)) 2014 ret = -EFAULT; 2015 actually_read += temp; 2016 tape->merge_bh_size = bytes_read-temp; 2017 } 2018finish: 2019 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) { 2020 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 2021 2022 idetape_space_over_filemarks(drive, MTFSF, 1); 2023 return 0; 2024 } 2025 2026 return ret ? ret : actually_read; 2027} 2028 2029static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 2030 size_t count, loff_t *ppos) 2031{ 2032 struct ide_tape_obj *tape = ide_tape_f(file); 2033 ide_drive_t *drive = tape->drive; 2034 ssize_t actually_written = 0; 2035 ssize_t ret = 0; 2036 u16 ctl = *(u16 *)&tape->caps[12]; 2037 2038 /* The drive is write protected. */ 2039 if (tape->write_prot) 2040 return -EACCES; 2041 2042 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 2043 2044 /* Initialize write operation */ 2045 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 2046 if (tape->chrdev_dir == IDETAPE_DIR_READ) 2047 ide_tape_discard_merge_buffer(drive, 1); 2048 if (tape->merge_bh || tape->merge_bh_size) { 2049 printk(KERN_ERR "ide-tape: merge_bh_size " 2050 "should be 0 now\n"); 2051 tape->merge_bh_size = 0; 2052 } 2053 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 2054 if (!tape->merge_bh) 2055 return -ENOMEM; 2056 tape->chrdev_dir = IDETAPE_DIR_WRITE; 2057 idetape_init_merge_buffer(tape); 2058 2059 /* 2060 * Issue a write 0 command to ensure that DSC handshake is 2061 * switched from completion mode to buffer available mode. No 2062 * point in issuing this if DSC overlap isn't supported, some 2063 * drives (Seagate STT3401A) will return an error. 2064 */ 2065 if (drive->dsc_overlap) { 2066 ssize_t retval = idetape_queue_rw_tail(drive, 2067 REQ_IDETAPE_WRITE, 0, 2068 tape->merge_bh); 2069 if (retval < 0) { 2070 ide_tape_kfree_buffer(tape); 2071 tape->merge_bh = NULL; 2072 tape->chrdev_dir = IDETAPE_DIR_NONE; 2073 return retval; 2074 } 2075 } 2076 } 2077 if (count == 0) 2078 return (0); 2079 if (tape->merge_bh_size) { 2080 if (tape->merge_bh_size >= tape->buffer_size) { 2081 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 2082 tape->merge_bh_size = 0; 2083 } 2084 actually_written = min((unsigned int) 2085 (tape->buffer_size - tape->merge_bh_size), 2086 (unsigned int)count); 2087 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 2088 ret = -EFAULT; 2089 buf += actually_written; 2090 tape->merge_bh_size += actually_written; 2091 count -= actually_written; 2092 2093 if (tape->merge_bh_size == tape->buffer_size) { 2094 ssize_t retval; 2095 tape->merge_bh_size = 0; 2096 retval = idetape_add_chrdev_write_request(drive, ctl); 2097 if (retval <= 0) 2098 return (retval); 2099 } 2100 } 2101 while (count >= tape->buffer_size) { 2102 ssize_t retval; 2103 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 2104 ret = -EFAULT; 2105 buf += tape->buffer_size; 2106 count -= tape->buffer_size; 2107 retval = idetape_add_chrdev_write_request(drive, ctl); 2108 actually_written += tape->buffer_size; 2109 if (retval <= 0) 2110 return (retval); 2111 } 2112 if (count) { 2113 actually_written += count; 2114 if (idetape_copy_stage_from_user(tape, buf, count)) 2115 ret = -EFAULT; 2116 tape->merge_bh_size += count; 2117 } 2118 return ret ? ret : actually_written; 2119} 2120 2121static int idetape_write_filemark(ide_drive_t *drive) 2122{ 2123 struct ide_atapi_pc pc; 2124 2125 /* Write a filemark */ 2126 idetape_create_write_filemark_cmd(drive, &pc, 1); 2127 if (idetape_queue_pc_tail(drive, &pc)) { 2128 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 2129 return -EIO; 2130 } 2131 return 0; 2132} 2133 2134/* 2135 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 2136 * requested. 2137 * 2138 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 2139 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 2140 * usually not supported. 2141 * 2142 * The following commands are currently not supported: 2143 * 2144 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 2145 * MT_ST_WRITE_THRESHOLD. 2146 */ 2147static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 2148{ 2149 idetape_tape_t *tape = drive->driver_data; 2150 struct ide_atapi_pc pc; 2151 int i, retval; 2152 2153 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 2154 mt_op, mt_count); 2155 2156 switch (mt_op) { 2157 case MTFSF: 2158 case MTFSFM: 2159 case MTBSF: 2160 case MTBSFM: 2161 if (!mt_count) 2162 return 0; 2163 return idetape_space_over_filemarks(drive, mt_op, mt_count); 2164 default: 2165 break; 2166 } 2167 2168 switch (mt_op) { 2169 case MTWEOF: 2170 if (tape->write_prot) 2171 return -EACCES; 2172 ide_tape_discard_merge_buffer(drive, 1); 2173 for (i = 0; i < mt_count; i++) { 2174 retval = idetape_write_filemark(drive); 2175 if (retval) 2176 return retval; 2177 } 2178 return 0; 2179 case MTREW: 2180 ide_tape_discard_merge_buffer(drive, 0); 2181 if (idetape_rewind_tape(drive)) 2182 return -EIO; 2183 return 0; 2184 case MTLOAD: 2185 ide_tape_discard_merge_buffer(drive, 0); 2186 idetape_create_load_unload_cmd(drive, &pc, 2187 IDETAPE_LU_LOAD_MASK); 2188 return idetape_queue_pc_tail(drive, &pc); 2189 case MTUNLOAD: 2190 case MTOFFL: 2191 /* 2192 * If door is locked, attempt to unlock before 2193 * attempting to eject. 2194 */ 2195 if (tape->door_locked) { 2196 if (idetape_create_prevent_cmd(drive, &pc, 0)) 2197 if (!idetape_queue_pc_tail(drive, &pc)) 2198 tape->door_locked = DOOR_UNLOCKED; 2199 } 2200 ide_tape_discard_merge_buffer(drive, 0); 2201 idetape_create_load_unload_cmd(drive, &pc, 2202 !IDETAPE_LU_LOAD_MASK); 2203 retval = idetape_queue_pc_tail(drive, &pc); 2204 if (!retval) 2205 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 2206 return retval; 2207 case MTNOP: 2208 ide_tape_discard_merge_buffer(drive, 0); 2209 return idetape_flush_tape_buffers(drive); 2210 case MTRETEN: 2211 ide_tape_discard_merge_buffer(drive, 0); 2212 idetape_create_load_unload_cmd(drive, &pc, 2213 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 2214 return idetape_queue_pc_tail(drive, &pc); 2215 case MTEOM: 2216 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 2217 return idetape_queue_pc_tail(drive, &pc); 2218 case MTERASE: 2219 (void)idetape_rewind_tape(drive); 2220 idetape_create_erase_cmd(&pc); 2221 return idetape_queue_pc_tail(drive, &pc); 2222 case MTSETBLK: 2223 if (mt_count) { 2224 if (mt_count < tape->blk_size || 2225 mt_count % tape->blk_size) 2226 return -EIO; 2227 tape->user_bs_factor = mt_count / tape->blk_size; 2228 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2229 } else 2230 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2231 return 0; 2232 case MTSEEK: 2233 ide_tape_discard_merge_buffer(drive, 0); 2234 return idetape_position_tape(drive, 2235 mt_count * tape->user_bs_factor, tape->partition, 0); 2236 case MTSETPART: 2237 ide_tape_discard_merge_buffer(drive, 0); 2238 return idetape_position_tape(drive, 0, mt_count, 0); 2239 case MTFSR: 2240 case MTBSR: 2241 case MTLOCK: 2242 if (!idetape_create_prevent_cmd(drive, &pc, 1)) 2243 return 0; 2244 retval = idetape_queue_pc_tail(drive, &pc); 2245 if (retval) 2246 return retval; 2247 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 2248 return 0; 2249 case MTUNLOCK: 2250 if (!idetape_create_prevent_cmd(drive, &pc, 0)) 2251 return 0; 2252 retval = idetape_queue_pc_tail(drive, &pc); 2253 if (retval) 2254 return retval; 2255 tape->door_locked = DOOR_UNLOCKED; 2256 return 0; 2257 default: 2258 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 2259 mt_op); 2260 return -EIO; 2261 } 2262} 2263 2264/* 2265 * Our character device ioctls. General mtio.h magnetic io commands are 2266 * supported here, and not in the corresponding block interface. Our own 2267 * ide-tape ioctls are supported on both interfaces. 2268 */ 2269static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 2270 unsigned int cmd, unsigned long arg) 2271{ 2272 struct ide_tape_obj *tape = ide_tape_f(file); 2273 ide_drive_t *drive = tape->drive; 2274 struct mtop mtop; 2275 struct mtget mtget; 2276 struct mtpos mtpos; 2277 int block_offset = 0, position = tape->first_frame; 2278 void __user *argp = (void __user *)arg; 2279 2280 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 2281 2282 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 2283 ide_tape_flush_merge_buffer(drive); 2284 idetape_flush_tape_buffers(drive); 2285 } 2286 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 2287 block_offset = tape->merge_bh_size / 2288 (tape->blk_size * tape->user_bs_factor); 2289 position = idetape_read_position(drive); 2290 if (position < 0) 2291 return -EIO; 2292 } 2293 switch (cmd) { 2294 case MTIOCTOP: 2295 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 2296 return -EFAULT; 2297 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 2298 case MTIOCGET: 2299 memset(&mtget, 0, sizeof(struct mtget)); 2300 mtget.mt_type = MT_ISSCSI2; 2301 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 2302 mtget.mt_dsreg = 2303 ((tape->blk_size * tape->user_bs_factor) 2304 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 2305 2306 if (tape->drv_write_prot) 2307 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 2308 2309 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 2310 return -EFAULT; 2311 return 0; 2312 case MTIOCPOS: 2313 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 2314 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 2315 return -EFAULT; 2316 return 0; 2317 default: 2318 if (tape->chrdev_dir == IDETAPE_DIR_READ) 2319 ide_tape_discard_merge_buffer(drive, 1); 2320 return idetape_blkdev_ioctl(drive, cmd, arg); 2321 } 2322} 2323 2324/* 2325 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 2326 * block size with the reported value. 2327 */ 2328static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 2329{ 2330 idetape_tape_t *tape = drive->driver_data; 2331 struct ide_atapi_pc pc; 2332 2333 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 2334 if (idetape_queue_pc_tail(drive, &pc)) { 2335 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 2336 if (tape->blk_size == 0) { 2337 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 2338 "block size, assuming 32k\n"); 2339 tape->blk_size = 32768; 2340 } 2341 return; 2342 } 2343 tape->blk_size = (pc.buf[4 + 5] << 16) + 2344 (pc.buf[4 + 6] << 8) + 2345 pc.buf[4 + 7]; 2346 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 2347} 2348 2349static int idetape_chrdev_open(struct inode *inode, struct file *filp) 2350{ 2351 unsigned int minor = iminor(inode), i = minor & ~0xc0; 2352 ide_drive_t *drive; 2353 idetape_tape_t *tape; 2354 struct ide_atapi_pc pc; 2355 int retval; 2356 2357 if (i >= MAX_HWIFS * MAX_DRIVES) 2358 return -ENXIO; 2359 2360 tape = ide_tape_chrdev_get(i); 2361 if (!tape) 2362 return -ENXIO; 2363 2364 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2365 2366 /* 2367 * We really want to do nonseekable_open(inode, filp); here, but some 2368 * versions of tar incorrectly call lseek on tapes and bail out if that 2369 * fails. So we disallow pread() and pwrite(), but permit lseeks. 2370 */ 2371 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 2372 2373 drive = tape->drive; 2374 2375 filp->private_data = tape; 2376 2377 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) { 2378 retval = -EBUSY; 2379 goto out_put_tape; 2380 } 2381 2382 retval = idetape_wait_ready(drive, 60 * HZ); 2383 if (retval) { 2384 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2385 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 2386 goto out_put_tape; 2387 } 2388 2389 idetape_read_position(drive); 2390 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags)) 2391 (void)idetape_rewind_tape(drive); 2392 2393 /* Read block size and write protect status from drive. */ 2394 ide_tape_get_bsize_from_bdesc(drive); 2395 2396 /* Set write protect flag if device is opened as read-only. */ 2397 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 2398 tape->write_prot = 1; 2399 else 2400 tape->write_prot = tape->drv_write_prot; 2401 2402 /* Make sure drive isn't write protected if user wants to write. */ 2403 if (tape->write_prot) { 2404 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 2405 (filp->f_flags & O_ACCMODE) == O_RDWR) { 2406 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2407 retval = -EROFS; 2408 goto out_put_tape; 2409 } 2410 } 2411 2412 /* Lock the tape drive door so user can't eject. */ 2413 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2414 if (idetape_create_prevent_cmd(drive, &pc, 1)) { 2415 if (!idetape_queue_pc_tail(drive, &pc)) { 2416 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 2417 tape->door_locked = DOOR_LOCKED; 2418 } 2419 } 2420 } 2421 return 0; 2422 2423out_put_tape: 2424 ide_tape_put(tape); 2425 return retval; 2426} 2427 2428static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 2429{ 2430 idetape_tape_t *tape = drive->driver_data; 2431 2432 ide_tape_flush_merge_buffer(drive); 2433 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 2434 if (tape->merge_bh != NULL) { 2435 idetape_pad_zeros(drive, tape->blk_size * 2436 (tape->user_bs_factor - 1)); 2437 ide_tape_kfree_buffer(tape); 2438 tape->merge_bh = NULL; 2439 } 2440 idetape_write_filemark(drive); 2441 idetape_flush_tape_buffers(drive); 2442 idetape_flush_tape_buffers(drive); 2443} 2444 2445static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2446{ 2447 struct ide_tape_obj *tape = ide_tape_f(filp); 2448 ide_drive_t *drive = tape->drive; 2449 struct ide_atapi_pc pc; 2450 unsigned int minor = iminor(inode); 2451 2452 lock_kernel(); 2453 tape = drive->driver_data; 2454 2455 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2456 2457 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2458 idetape_write_release(drive, minor); 2459 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2460 if (minor < 128) 2461 ide_tape_discard_merge_buffer(drive, 1); 2462 } 2463 2464 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags)) 2465 (void) idetape_rewind_tape(drive); 2466 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2467 if (tape->door_locked == DOOR_LOCKED) { 2468 if (idetape_create_prevent_cmd(drive, &pc, 0)) { 2469 if (!idetape_queue_pc_tail(drive, &pc)) 2470 tape->door_locked = DOOR_UNLOCKED; 2471 } 2472 } 2473 } 2474 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2475 ide_tape_put(tape); 2476 unlock_kernel(); 2477 return 0; 2478} 2479 2480/* 2481 * check the contents of the ATAPI IDENTIFY command results. We return: 2482 * 2483 * 1 - If the tape can be supported by us, based on the information we have so 2484 * far. 2485 * 2486 * 0 - If this tape driver is not currently supported by us. 2487 */ 2488static int idetape_identify_device(ide_drive_t *drive) 2489{ 2490 u8 gcw[2], protocol, device_type, removable, packet_size; 2491 2492 if (drive->id_read == 0) 2493 return 1; 2494 2495 *((unsigned short *) &gcw) = drive->id->config; 2496 2497 protocol = (gcw[1] & 0xC0) >> 6; 2498 device_type = gcw[1] & 0x1F; 2499 removable = !!(gcw[0] & 0x80); 2500 packet_size = gcw[0] & 0x3; 2501 2502 /* Check that we can support this device */ 2503 if (protocol != 2) 2504 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n", 2505 protocol); 2506 else if (device_type != 1) 2507 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set " 2508 "to tape\n", device_type); 2509 else if (!removable) 2510 printk(KERN_ERR "ide-tape: The removable flag is not set\n"); 2511 else if (packet_size != 0) { 2512 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12" 2513 " bytes\n", packet_size); 2514 } else 2515 return 1; 2516 return 0; 2517} 2518 2519static void idetape_get_inquiry_results(ide_drive_t *drive) 2520{ 2521 idetape_tape_t *tape = drive->driver_data; 2522 struct ide_atapi_pc pc; 2523 char fw_rev[6], vendor_id[10], product_id[18]; 2524 2525 idetape_create_inquiry_cmd(&pc); 2526 if (idetape_queue_pc_tail(drive, &pc)) { 2527 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2528 tape->name); 2529 return; 2530 } 2531 memcpy(vendor_id, &pc.buf[8], 8); 2532 memcpy(product_id, &pc.buf[16], 16); 2533 memcpy(fw_rev, &pc.buf[32], 4); 2534 2535 ide_fixstring(vendor_id, 10, 0); 2536 ide_fixstring(product_id, 18, 0); 2537 ide_fixstring(fw_rev, 6, 0); 2538 2539 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n", 2540 drive->name, tape->name, vendor_id, product_id, fw_rev); 2541} 2542 2543/* 2544 * Ask the tape about its various parameters. In particular, we will adjust our 2545 * data transfer buffer size to the recommended value as returned by the tape. 2546 */ 2547static void idetape_get_mode_sense_results(ide_drive_t *drive) 2548{ 2549 idetape_tape_t *tape = drive->driver_data; 2550 struct ide_atapi_pc pc; 2551 u8 *caps; 2552 u8 speed, max_speed; 2553 2554 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2555 if (idetape_queue_pc_tail(drive, &pc)) { 2556 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2557 " some default values\n"); 2558 tape->blk_size = 512; 2559 put_unaligned(52, (u16 *)&tape->caps[12]); 2560 put_unaligned(540, (u16 *)&tape->caps[14]); 2561 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2562 return; 2563 } 2564 caps = pc.buf + 4 + pc.buf[3]; 2565 2566 /* convert to host order and save for later use */ 2567 speed = be16_to_cpu(*(u16 *)&caps[14]); 2568 max_speed = be16_to_cpu(*(u16 *)&caps[8]); 2569 2570 put_unaligned(max_speed, (u16 *)&caps[8]); 2571 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]); 2572 put_unaligned(speed, (u16 *)&caps[14]); 2573 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]); 2574 2575 if (!speed) { 2576 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2577 "(assuming 650KB/sec)\n", drive->name); 2578 put_unaligned(650, (u16 *)&caps[14]); 2579 } 2580 if (!max_speed) { 2581 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2582 "(assuming 650KB/sec)\n", drive->name); 2583 put_unaligned(650, (u16 *)&caps[8]); 2584 } 2585 2586 memcpy(&tape->caps, caps, 20); 2587 if (caps[7] & 0x02) 2588 tape->blk_size = 512; 2589 else if (caps[7] & 0x04) 2590 tape->blk_size = 1024; 2591} 2592 2593#ifdef CONFIG_IDE_PROC_FS 2594static void idetape_add_settings(ide_drive_t *drive) 2595{ 2596 idetape_tape_t *tape = drive->driver_data; 2597 2598 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2599 1, 2, (u16 *)&tape->caps[16], NULL); 2600 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2601 1, 1, (u16 *)&tape->caps[14], NULL); 2602 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff, 2603 1, 1024, &tape->buffer_size, NULL); 2604 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN, 2605 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq, 2606 NULL); 2607 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1, 2608 1, &drive->dsc_overlap, NULL); 2609 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff, 2610 1, 1, &tape->avg_speed, NULL); 2611 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1, 2612 1, &tape->debug_mask, NULL); 2613} 2614#else 2615static inline void idetape_add_settings(ide_drive_t *drive) { ; } 2616#endif 2617 2618/* 2619 * The function below is called to: 2620 * 2621 * 1. Initialize our various state variables. 2622 * 2. Ask the tape for its capabilities. 2623 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2624 * is chosen based on the recommendation which we received in step 2. 2625 * 2626 * Note that at this point ide.c already assigned us an irq, so that we can 2627 * queue requests here and wait for their completion. 2628 */ 2629static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2630{ 2631 unsigned long t; 2632 int speed; 2633 int buffer_size; 2634 u8 gcw[2]; 2635 u16 *ctl = (u16 *)&tape->caps[12]; 2636 2637 spin_lock_init(&tape->lock); 2638 drive->dsc_overlap = 1; 2639 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2640 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2641 tape->name); 2642 drive->dsc_overlap = 0; 2643 } 2644 /* Seagate Travan drives do not support DSC overlap. */ 2645 if (strstr(drive->id->model, "Seagate STT3401")) 2646 drive->dsc_overlap = 0; 2647 tape->minor = minor; 2648 tape->name[0] = 'h'; 2649 tape->name[1] = 't'; 2650 tape->name[2] = '0' + minor; 2651 tape->chrdev_dir = IDETAPE_DIR_NONE; 2652 tape->pc = tape->pc_stack; 2653 *((unsigned short *) &gcw) = drive->id->config; 2654 2655 /* Command packet DRQ type */ 2656 if (((gcw[0] & 0x60) >> 5) == 1) 2657 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags); 2658 2659 idetape_get_inquiry_results(drive); 2660 idetape_get_mode_sense_results(drive); 2661 ide_tape_get_bsize_from_bdesc(drive); 2662 tape->user_bs_factor = 1; 2663 tape->buffer_size = *ctl * tape->blk_size; 2664 while (tape->buffer_size > 0xffff) { 2665 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2666 *ctl /= 2; 2667 tape->buffer_size = *ctl * tape->blk_size; 2668 } 2669 buffer_size = tape->buffer_size; 2670 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2671 if (buffer_size % PAGE_SIZE) { 2672 tape->pages_per_buffer++; 2673 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2674 } 2675 2676 /* select the "best" DSC read/write polling freq */ 2677 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2678 2679 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2680 2681 /* 2682 * Ensure that the number we got makes sense; limit it within 2683 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2684 */ 2685 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2686 IDETAPE_DSC_RW_MAX); 2687 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2688 "%lums tDSC%s\n", 2689 drive->name, tape->name, *(u16 *)&tape->caps[14], 2690 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2691 tape->buffer_size / 1024, 2692 tape->best_dsc_rw_freq * 1000 / HZ, 2693 drive->using_dma ? ", DMA":""); 2694 2695 idetape_add_settings(drive); 2696} 2697 2698static void ide_tape_remove(ide_drive_t *drive) 2699{ 2700 idetape_tape_t *tape = drive->driver_data; 2701 2702 ide_proc_unregister_driver(drive, tape->driver); 2703 2704 ide_unregister_region(tape->disk); 2705 2706 ide_tape_put(tape); 2707} 2708 2709static void ide_tape_release(struct kref *kref) 2710{ 2711 struct ide_tape_obj *tape = to_ide_tape(kref); 2712 ide_drive_t *drive = tape->drive; 2713 struct gendisk *g = tape->disk; 2714 2715 BUG_ON(tape->merge_bh_size); 2716 2717 drive->dsc_overlap = 0; 2718 drive->driver_data = NULL; 2719 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2720 device_destroy(idetape_sysfs_class, 2721 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2722 idetape_devs[tape->minor] = NULL; 2723 g->private_data = NULL; 2724 put_disk(g); 2725 kfree(tape); 2726} 2727 2728#ifdef CONFIG_IDE_PROC_FS 2729static int proc_idetape_read_name 2730 (char *page, char **start, off_t off, int count, int *eof, void *data) 2731{ 2732 ide_drive_t *drive = (ide_drive_t *) data; 2733 idetape_tape_t *tape = drive->driver_data; 2734 char *out = page; 2735 int len; 2736 2737 len = sprintf(out, "%s\n", tape->name); 2738 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2739} 2740 2741static ide_proc_entry_t idetape_proc[] = { 2742 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2743 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2744 { NULL, 0, NULL, NULL } 2745}; 2746#endif 2747 2748static int ide_tape_probe(ide_drive_t *); 2749 2750static ide_driver_t idetape_driver = { 2751 .gen_driver = { 2752 .owner = THIS_MODULE, 2753 .name = "ide-tape", 2754 .bus = &ide_bus_type, 2755 }, 2756 .probe = ide_tape_probe, 2757 .remove = ide_tape_remove, 2758 .version = IDETAPE_VERSION, 2759 .media = ide_tape, 2760 .supports_dsc_overlap = 1, 2761 .do_request = idetape_do_request, 2762 .end_request = idetape_end_request, 2763 .error = __ide_error, 2764 .abort = __ide_abort, 2765#ifdef CONFIG_IDE_PROC_FS 2766 .proc = idetape_proc, 2767#endif 2768}; 2769 2770/* Our character device supporting functions, passed to register_chrdev. */ 2771static const struct file_operations idetape_fops = { 2772 .owner = THIS_MODULE, 2773 .read = idetape_chrdev_read, 2774 .write = idetape_chrdev_write, 2775 .ioctl = idetape_chrdev_ioctl, 2776 .open = idetape_chrdev_open, 2777 .release = idetape_chrdev_release, 2778}; 2779 2780static int idetape_open(struct inode *inode, struct file *filp) 2781{ 2782 struct gendisk *disk = inode->i_bdev->bd_disk; 2783 struct ide_tape_obj *tape; 2784 2785 tape = ide_tape_get(disk); 2786 if (!tape) 2787 return -ENXIO; 2788 2789 return 0; 2790} 2791 2792static int idetape_release(struct inode *inode, struct file *filp) 2793{ 2794 struct gendisk *disk = inode->i_bdev->bd_disk; 2795 struct ide_tape_obj *tape = ide_tape_g(disk); 2796 2797 ide_tape_put(tape); 2798 2799 return 0; 2800} 2801 2802static int idetape_ioctl(struct inode *inode, struct file *file, 2803 unsigned int cmd, unsigned long arg) 2804{ 2805 struct block_device *bdev = inode->i_bdev; 2806 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 2807 ide_drive_t *drive = tape->drive; 2808 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 2809 if (err == -EINVAL) 2810 err = idetape_blkdev_ioctl(drive, cmd, arg); 2811 return err; 2812} 2813 2814static struct block_device_operations idetape_block_ops = { 2815 .owner = THIS_MODULE, 2816 .open = idetape_open, 2817 .release = idetape_release, 2818 .ioctl = idetape_ioctl, 2819}; 2820 2821static int ide_tape_probe(ide_drive_t *drive) 2822{ 2823 idetape_tape_t *tape; 2824 struct gendisk *g; 2825 int minor; 2826 2827 if (!strstr("ide-tape", drive->driver_req)) 2828 goto failed; 2829 if (!drive->present) 2830 goto failed; 2831 if (drive->media != ide_tape) 2832 goto failed; 2833 if (!idetape_identify_device(drive)) { 2834 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2835 " the driver\n", drive->name); 2836 goto failed; 2837 } 2838 if (drive->scsi) { 2839 printk(KERN_INFO "ide-tape: passing drive %s to ide-scsi" 2840 " emulation.\n", drive->name); 2841 goto failed; 2842 } 2843 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2844 if (tape == NULL) { 2845 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2846 drive->name); 2847 goto failed; 2848 } 2849 2850 g = alloc_disk(1 << PARTN_BITS); 2851 if (!g) 2852 goto out_free_tape; 2853 2854 ide_init_disk(g, drive); 2855 2856 ide_proc_register_driver(drive, &idetape_driver); 2857 2858 kref_init(&tape->kref); 2859 2860 tape->drive = drive; 2861 tape->driver = &idetape_driver; 2862 tape->disk = g; 2863 2864 g->private_data = &tape->driver; 2865 2866 drive->driver_data = tape; 2867 2868 mutex_lock(&idetape_ref_mutex); 2869 for (minor = 0; idetape_devs[minor]; minor++) 2870 ; 2871 idetape_devs[minor] = tape; 2872 mutex_unlock(&idetape_ref_mutex); 2873 2874 idetape_setup(drive, tape, minor); 2875 2876 device_create(idetape_sysfs_class, &drive->gendev, 2877 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name); 2878 device_create(idetape_sysfs_class, &drive->gendev, 2879 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name); 2880 2881 g->fops = &idetape_block_ops; 2882 ide_register_region(g); 2883 2884 return 0; 2885 2886out_free_tape: 2887 kfree(tape); 2888failed: 2889 return -ENODEV; 2890} 2891 2892static void __exit idetape_exit(void) 2893{ 2894 driver_unregister(&idetape_driver.gen_driver); 2895 class_destroy(idetape_sysfs_class); 2896 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2897} 2898 2899static int __init idetape_init(void) 2900{ 2901 int error = 1; 2902 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2903 if (IS_ERR(idetape_sysfs_class)) { 2904 idetape_sysfs_class = NULL; 2905 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2906 error = -EBUSY; 2907 goto out; 2908 } 2909 2910 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2911 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2912 " interface\n"); 2913 error = -EBUSY; 2914 goto out_free_class; 2915 } 2916 2917 error = driver_register(&idetape_driver.gen_driver); 2918 if (error) 2919 goto out_free_driver; 2920 2921 return 0; 2922 2923out_free_driver: 2924 driver_unregister(&idetape_driver.gen_driver); 2925out_free_class: 2926 class_destroy(idetape_sysfs_class); 2927out: 2928 return error; 2929} 2930 2931MODULE_ALIAS("ide:*m-tape*"); 2932module_init(idetape_init); 2933module_exit(idetape_exit); 2934MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2935MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2936MODULE_LICENSE("GPL"); 2937