ide-tape.c revision 9fd13a27c8a35ff1986793cb96aaedb5e75b5368
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 void 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 680static void idetape_init_pc(struct ide_atapi_pc *pc) 681{ 682 memset(pc->c, 0, 12); 683 pc->retries = 0; 684 pc->flags = 0; 685 pc->req_xfer = 0; 686 pc->buf = pc->pc_buf; 687 pc->buf_size = IDETAPE_PC_BUFFER_SIZE; 688 pc->bh = NULL; 689 pc->b_data = NULL; 690 pc->callback = ide_tape_callback; 691} 692 693static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc) 694{ 695 idetape_init_pc(pc); 696 pc->c[0] = REQUEST_SENSE; 697 pc->c[4] = 20; 698 pc->req_xfer = 20; 699} 700 701static void idetape_init_rq(struct request *rq, u8 cmd) 702{ 703 blk_rq_init(NULL, rq); 704 rq->cmd_type = REQ_TYPE_SPECIAL; 705 rq->cmd[0] = cmd; 706} 707 708/* 709 * Generate a new packet command request in front of the request queue, before 710 * the current request, so that it will be processed immediately, on the next 711 * pass through the driver. The function below is called from the request 712 * handling part of the driver (the "bottom" part). Safe storage for the request 713 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that. 714 * 715 * Memory for those requests is pre-allocated at initialization time, and is 716 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for 717 * the maximum possible number of inter-dependent packet commands. 718 * 719 * The higher level of the driver - The ioctl handler and the character device 720 * handling functions should queue request to the lower level part and wait for 721 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail. 722 */ 723static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc, 724 struct request *rq) 725{ 726 struct ide_tape_obj *tape = drive->driver_data; 727 728 idetape_init_rq(rq, REQ_IDETAPE_PC1); 729 rq->cmd_flags |= REQ_PREEMPT; 730 rq->buffer = (char *) pc; 731 rq->rq_disk = tape->disk; 732 ide_do_drive_cmd(drive, rq); 733} 734 735/* 736 * idetape_retry_pc is called when an error was detected during the 737 * last packet command. We queue a request sense packet command in 738 * the head of the request list. 739 */ 740static void idetape_retry_pc(ide_drive_t *drive) 741{ 742 idetape_tape_t *tape = drive->driver_data; 743 struct ide_atapi_pc *pc; 744 struct request *rq; 745 746 (void)ide_read_error(drive); 747 pc = idetape_next_pc_storage(drive); 748 rq = idetape_next_rq_storage(drive); 749 idetape_create_request_sense_cmd(pc); 750 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 751 idetape_queue_pc_head(drive, pc, rq); 752} 753 754/* 755 * Postpone the current request so that ide.c will be able to service requests 756 * from another device on the same hwgroup while we are polling for DSC. 757 */ 758static void idetape_postpone_request(ide_drive_t *drive) 759{ 760 idetape_tape_t *tape = drive->driver_data; 761 762 debug_log(DBG_PROCS, "Enter %s\n", __func__); 763 764 tape->postponed_rq = HWGROUP(drive)->rq; 765 ide_stall_queue(drive, tape->dsc_poll_freq); 766} 767 768typedef void idetape_io_buf(ide_drive_t *, struct ide_atapi_pc *, unsigned int); 769 770/* 771 * This is the usual interrupt handler which will be called during a packet 772 * command. We will transfer some of the data (as requested by the drive) and 773 * will re-point interrupt handler to us. When data transfer is finished, we 774 * will act according to the algorithm described before 775 * idetape_issue_pc. 776 */ 777static ide_startstop_t idetape_pc_intr(ide_drive_t *drive) 778{ 779 ide_hwif_t *hwif = drive->hwif; 780 idetape_tape_t *tape = drive->driver_data; 781 struct ide_atapi_pc *pc = tape->pc; 782 xfer_func_t *xferfunc; 783 idetape_io_buf *iobuf; 784 unsigned int temp; 785 u16 bcount; 786 u8 stat, ireason; 787 788 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__); 789 790 /* Clear the interrupt */ 791 stat = ide_read_status(drive); 792 793 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 794 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) { 795 pc->flags |= PC_FLAG_DMA_ERROR; 796 } else { 797 pc->xferred = pc->req_xfer; 798 idetape_update_buffers(pc); 799 } 800 debug_log(DBG_PROCS, "DMA finished\n"); 801 802 } 803 804 /* No more interrupts */ 805 if ((stat & DRQ_STAT) == 0) { 806 debug_log(DBG_SENSE, "Packet command completed, %d bytes" 807 " transferred\n", pc->xferred); 808 809 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 810 local_irq_enable_in_hardirq(); 811 812 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE) 813 stat &= ~ERR_STAT; 814 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) { 815 /* Error detected */ 816 debug_log(DBG_ERR, "%s: I/O error\n", tape->name); 817 818 if (pc->c[0] == REQUEST_SENSE) { 819 printk(KERN_ERR "%s: I/O error in request sense" 820 " command\n", drive->name); 821 return ide_do_reset(drive); 822 } 823 debug_log(DBG_ERR, "[cmd %x]: check condition\n", 824 pc->c[0]); 825 826 /* Retry operation */ 827 idetape_retry_pc(drive); 828 return ide_stopped; 829 } 830 pc->error = 0; 831 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && 832 (stat & SEEK_STAT) == 0) { 833 /* Media access command */ 834 tape->dsc_polling_start = jiffies; 835 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 836 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 837 /* Allow ide.c to handle other requests */ 838 idetape_postpone_request(drive); 839 return ide_stopped; 840 } 841 if (tape->failed_pc == pc) 842 tape->failed_pc = NULL; 843 /* Command finished - Call the callback function */ 844 pc->callback(drive); 845 return ide_stopped; 846 } 847 848 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 849 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 850 printk(KERN_ERR "%s: The device wants to issue more interrupts " 851 "in DMA mode\n", drive->name); 852 ide_dma_off(drive); 853 return ide_do_reset(drive); 854 } 855 /* Get the number of bytes to transfer on this interrupt. */ 856 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) | 857 hwif->INB(hwif->io_ports.lbam_addr); 858 859 ireason = hwif->INB(hwif->io_ports.nsect_addr); 860 861 if (ireason & CD) { 862 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__); 863 return ide_do_reset(drive); 864 } 865 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) { 866 /* Hopefully, we will never get here */ 867 printk(KERN_ERR "%s: We wanted to %s, but the device wants us " 868 "to %s!\n", drive->name, 869 (ireason & IO) ? "Write" : "Read", 870 (ireason & IO) ? "Read" : "Write"); 871 return ide_do_reset(drive); 872 } 873 if (!(pc->flags & PC_FLAG_WRITING)) { 874 /* Reading - Check that we have enough space */ 875 temp = pc->xferred + bcount; 876 if (temp > pc->req_xfer) { 877 if (temp > pc->buf_size) { 878 printk(KERN_ERR "%s: The device wants to send " 879 "us more data than expected - " 880 "discarding data\n", 881 drive->name); 882 ide_pad_transfer(drive, 0, bcount); 883 ide_set_handler(drive, &idetape_pc_intr, 884 IDETAPE_WAIT_CMD, NULL); 885 return ide_started; 886 } 887 debug_log(DBG_SENSE, "The device wants to send us more " 888 "data than expected - allowing transfer\n"); 889 } 890 iobuf = &idetape_input_buffers; 891 xferfunc = hwif->input_data; 892 } else { 893 iobuf = &idetape_output_buffers; 894 xferfunc = hwif->output_data; 895 } 896 897 if (pc->bh) 898 iobuf(drive, pc, bcount); 899 else 900 xferfunc(drive, NULL, pc->cur_pos, bcount); 901 902 /* Update the current position */ 903 pc->xferred += bcount; 904 pc->cur_pos += bcount; 905 906 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n", 907 pc->c[0], bcount); 908 909 /* And set the interrupt handler again */ 910 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 911 return ide_started; 912} 913 914/* 915 * Packet Command Interface 916 * 917 * The current Packet Command is available in tape->pc, and will not change 918 * until we finish handling it. Each packet command is associated with a 919 * callback function that will be called when the command is finished. 920 * 921 * The handling will be done in three stages: 922 * 923 * 1. idetape_issue_pc will send the packet command to the drive, and will set 924 * the interrupt handler to idetape_pc_intr. 925 * 926 * 2. On each interrupt, idetape_pc_intr will be called. This step will be 927 * repeated until the device signals us that no more interrupts will be issued. 928 * 929 * 3. ATAPI Tape media access commands have immediate status with a delayed 930 * process. In case of a successful initiation of a media access packet command, 931 * the DSC bit will be set when the actual execution of the command is finished. 932 * Since the tape drive will not issue an interrupt, we have to poll for this 933 * event. In this case, we define the request as "low priority request" by 934 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 935 * exit the driver. 936 * 937 * ide.c will then give higher priority to requests which originate from the 938 * other device, until will change rq_status to RQ_ACTIVE. 939 * 940 * 4. When the packet command is finished, it will be checked for errors. 941 * 942 * 5. In case an error was found, we queue a request sense packet command in 943 * front of the request queue and retry the operation up to 944 * IDETAPE_MAX_PC_RETRIES times. 945 * 946 * 6. In case no error was found, or we decided to give up and not to retry 947 * again, the callback function will be called and then we will handle the next 948 * request. 949 */ 950static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 951{ 952 ide_hwif_t *hwif = drive->hwif; 953 idetape_tape_t *tape = drive->driver_data; 954 struct ide_atapi_pc *pc = tape->pc; 955 int retries = 100; 956 ide_startstop_t startstop; 957 u8 ireason; 958 959 if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) { 960 printk(KERN_ERR "%s: Strange, packet command initiated yet " 961 "DRQ isn't asserted\n", drive->name); 962 return startstop; 963 } 964 ireason = hwif->INB(hwif->io_ports.nsect_addr); 965 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) { 966 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing " 967 "a packet command, retrying\n", drive->name); 968 udelay(100); 969 ireason = hwif->INB(hwif->io_ports.nsect_addr); 970 if (retries == 0) { 971 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing " 972 "a packet command, ignoring\n", 973 drive->name); 974 ireason |= CD; 975 ireason &= ~IO; 976 } 977 } 978 if ((ireason & CD) == 0 || (ireason & IO)) { 979 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing " 980 "a packet command\n", drive->name); 981 return ide_do_reset(drive); 982 } 983 /* Set the interrupt routine */ 984 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 985 986 /* Begin DMA, if necessary */ 987 if (pc->flags & PC_FLAG_DMA_OK) { 988 pc->flags |= PC_FLAG_DMA_IN_PROGRESS; 989 hwif->dma_ops->dma_start(drive); 990 } 991 992 /* Send the actual packet */ 993 hwif->output_data(drive, NULL, pc->c, 12); 994 995 return ide_started; 996} 997 998static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 999 struct ide_atapi_pc *pc) 1000{ 1001 ide_hwif_t *hwif = drive->hwif; 1002 idetape_tape_t *tape = drive->driver_data; 1003 int dma_ok = 0; 1004 u16 bcount; 1005 1006 if (tape->pc->c[0] == REQUEST_SENSE && 1007 pc->c[0] == REQUEST_SENSE) { 1008 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 1009 "Two request sense in serial were issued\n"); 1010 } 1011 1012 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 1013 tape->failed_pc = pc; 1014 /* Set the current packet command */ 1015 tape->pc = pc; 1016 1017 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 1018 (pc->flags & PC_FLAG_ABORT)) { 1019 /* 1020 * We will "abort" retrying a packet command in case legitimate 1021 * error code was received (crossing a filemark, or end of the 1022 * media, for example). 1023 */ 1024 if (!(pc->flags & PC_FLAG_ABORT)) { 1025 if (!(pc->c[0] == TEST_UNIT_READY && 1026 tape->sense_key == 2 && tape->asc == 4 && 1027 (tape->ascq == 1 || tape->ascq == 8))) { 1028 printk(KERN_ERR "ide-tape: %s: I/O error, " 1029 "pc = %2x, key = %2x, " 1030 "asc = %2x, ascq = %2x\n", 1031 tape->name, pc->c[0], 1032 tape->sense_key, tape->asc, 1033 tape->ascq); 1034 } 1035 /* Giving up */ 1036 pc->error = IDETAPE_ERROR_GENERAL; 1037 } 1038 tape->failed_pc = NULL; 1039 pc->callback(drive); 1040 return ide_stopped; 1041 } 1042 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 1043 1044 pc->retries++; 1045 /* We haven't transferred any data yet */ 1046 pc->xferred = 0; 1047 pc->cur_pos = pc->buf; 1048 /* Request to transfer the entire buffer at once */ 1049 bcount = pc->req_xfer; 1050 1051 if (pc->flags & PC_FLAG_DMA_ERROR) { 1052 pc->flags &= ~PC_FLAG_DMA_ERROR; 1053 ide_dma_off(drive); 1054 } 1055 if ((pc->flags & PC_FLAG_DMA_OK) && drive->using_dma) 1056 dma_ok = !hwif->dma_ops->dma_setup(drive); 1057 1058 if (!dma_ok) 1059 pc->flags &= ~PC_FLAG_DMA_OK; 1060 1061 ide_pktcmd_tf_load(drive, IDE_TFLAG_OUT_DEVICE, bcount, dma_ok); 1062 1063 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags)) { 1064 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc, 1065 IDETAPE_WAIT_CMD, NULL); 1066 return ide_started; 1067 } else { 1068 ide_execute_pkt_cmd(drive); 1069 return idetape_transfer_pc(drive); 1070 } 1071} 1072 1073/* A mode sense command is used to "sense" tape parameters. */ 1074static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 1075{ 1076 idetape_init_pc(pc); 1077 pc->c[0] = MODE_SENSE; 1078 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 1079 /* DBD = 1 - Don't return block descriptors */ 1080 pc->c[1] = 8; 1081 pc->c[2] = page_code; 1082 /* 1083 * Changed pc->c[3] to 0 (255 will at best return unused info). 1084 * 1085 * For SCSI this byte is defined as subpage instead of high byte 1086 * of length and some IDE drives seem to interpret it this way 1087 * and return an error when 255 is used. 1088 */ 1089 pc->c[3] = 0; 1090 /* We will just discard data in that case */ 1091 pc->c[4] = 255; 1092 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 1093 pc->req_xfer = 12; 1094 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 1095 pc->req_xfer = 24; 1096 else 1097 pc->req_xfer = 50; 1098} 1099 1100static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 1101{ 1102 idetape_tape_t *tape = drive->driver_data; 1103 struct ide_atapi_pc *pc = tape->pc; 1104 u8 stat; 1105 1106 stat = ide_read_status(drive); 1107 1108 if (stat & SEEK_STAT) { 1109 if (stat & ERR_STAT) { 1110 /* Error detected */ 1111 if (pc->c[0] != TEST_UNIT_READY) 1112 printk(KERN_ERR "ide-tape: %s: I/O error, ", 1113 tape->name); 1114 /* Retry operation */ 1115 idetape_retry_pc(drive); 1116 return ide_stopped; 1117 } 1118 pc->error = 0; 1119 if (tape->failed_pc == pc) 1120 tape->failed_pc = NULL; 1121 } else { 1122 pc->error = IDETAPE_ERROR_GENERAL; 1123 tape->failed_pc = NULL; 1124 } 1125 pc->callback(drive); 1126 return ide_stopped; 1127} 1128 1129static void idetape_create_read_cmd(idetape_tape_t *tape, 1130 struct ide_atapi_pc *pc, 1131 unsigned int length, struct idetape_bh *bh) 1132{ 1133 idetape_init_pc(pc); 1134 pc->c[0] = READ_6; 1135 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1136 pc->c[1] = 1; 1137 pc->bh = bh; 1138 atomic_set(&bh->b_count, 0); 1139 pc->buf = NULL; 1140 pc->buf_size = length * tape->blk_size; 1141 pc->req_xfer = pc->buf_size; 1142 if (pc->req_xfer == tape->buffer_size) 1143 pc->flags |= PC_FLAG_DMA_OK; 1144} 1145 1146static void idetape_create_write_cmd(idetape_tape_t *tape, 1147 struct ide_atapi_pc *pc, 1148 unsigned int length, struct idetape_bh *bh) 1149{ 1150 idetape_init_pc(pc); 1151 pc->c[0] = WRITE_6; 1152 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1153 pc->c[1] = 1; 1154 pc->flags |= PC_FLAG_WRITING; 1155 pc->bh = bh; 1156 pc->b_data = bh->b_data; 1157 pc->b_count = atomic_read(&bh->b_count); 1158 pc->buf = NULL; 1159 pc->buf_size = length * tape->blk_size; 1160 pc->req_xfer = pc->buf_size; 1161 if (pc->req_xfer == tape->buffer_size) 1162 pc->flags |= PC_FLAG_DMA_OK; 1163} 1164 1165static ide_startstop_t idetape_do_request(ide_drive_t *drive, 1166 struct request *rq, sector_t block) 1167{ 1168 idetape_tape_t *tape = drive->driver_data; 1169 struct ide_atapi_pc *pc = NULL; 1170 struct request *postponed_rq = tape->postponed_rq; 1171 u8 stat; 1172 1173 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld," 1174 " current_nr_sectors: %d\n", 1175 rq->sector, rq->nr_sectors, rq->current_nr_sectors); 1176 1177 if (!blk_special_request(rq)) { 1178 /* We do not support buffer cache originated requests. */ 1179 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 1180 "request queue (%d)\n", drive->name, rq->cmd_type); 1181 ide_end_request(drive, 0, 0); 1182 return ide_stopped; 1183 } 1184 1185 /* Retry a failed packet command */ 1186 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) 1187 return idetape_issue_pc(drive, tape->failed_pc); 1188 1189 if (postponed_rq != NULL) 1190 if (rq != postponed_rq) { 1191 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 1192 "Two DSC requests were queued\n"); 1193 idetape_end_request(drive, 0, 0); 1194 return ide_stopped; 1195 } 1196 1197 tape->postponed_rq = NULL; 1198 1199 /* 1200 * If the tape is still busy, postpone our request and service 1201 * the other device meanwhile. 1202 */ 1203 stat = ide_read_status(drive); 1204 1205 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2)) 1206 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1207 1208 if (drive->post_reset == 1) { 1209 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1210 drive->post_reset = 0; 1211 } 1212 1213 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) && 1214 (stat & SEEK_STAT) == 0) { 1215 if (postponed_rq == NULL) { 1216 tape->dsc_polling_start = jiffies; 1217 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 1218 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 1219 } else if (time_after(jiffies, tape->dsc_timeout)) { 1220 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 1221 tape->name); 1222 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1223 idetape_media_access_finished(drive); 1224 return ide_stopped; 1225 } else { 1226 return ide_do_reset(drive); 1227 } 1228 } else if (time_after(jiffies, 1229 tape->dsc_polling_start + 1230 IDETAPE_DSC_MA_THRESHOLD)) 1231 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 1232 idetape_postpone_request(drive); 1233 return ide_stopped; 1234 } 1235 if (rq->cmd[0] & REQ_IDETAPE_READ) { 1236 pc = idetape_next_pc_storage(drive); 1237 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, 1238 (struct idetape_bh *)rq->special); 1239 goto out; 1240 } 1241 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 1242 pc = idetape_next_pc_storage(drive); 1243 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, 1244 (struct idetape_bh *)rq->special); 1245 goto out; 1246 } 1247 if (rq->cmd[0] & REQ_IDETAPE_PC1) { 1248 pc = (struct ide_atapi_pc *) rq->buffer; 1249 rq->cmd[0] &= ~(REQ_IDETAPE_PC1); 1250 rq->cmd[0] |= REQ_IDETAPE_PC2; 1251 goto out; 1252 } 1253 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1254 idetape_media_access_finished(drive); 1255 return ide_stopped; 1256 } 1257 BUG(); 1258out: 1259 return idetape_issue_pc(drive, pc); 1260} 1261 1262/* 1263 * The function below uses __get_free_pages to allocate a data buffer of size 1264 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 1265 * much as possible. 1266 * 1267 * It returns a pointer to the newly allocated buffer, or NULL in case of 1268 * failure. 1269 */ 1270static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 1271 int full, int clear) 1272{ 1273 struct idetape_bh *prev_bh, *bh, *merge_bh; 1274 int pages = tape->pages_per_buffer; 1275 unsigned int order, b_allocd; 1276 char *b_data = NULL; 1277 1278 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1279 bh = merge_bh; 1280 if (bh == NULL) 1281 goto abort; 1282 1283 order = fls(pages) - 1; 1284 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1285 if (!bh->b_data) 1286 goto abort; 1287 b_allocd = (1 << order) * PAGE_SIZE; 1288 pages &= (order-1); 1289 1290 if (clear) 1291 memset(bh->b_data, 0, b_allocd); 1292 bh->b_reqnext = NULL; 1293 bh->b_size = b_allocd; 1294 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1295 1296 while (pages) { 1297 order = fls(pages) - 1; 1298 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1299 if (!b_data) 1300 goto abort; 1301 b_allocd = (1 << order) * PAGE_SIZE; 1302 1303 if (clear) 1304 memset(b_data, 0, b_allocd); 1305 1306 /* newly allocated page frames below buffer header or ...*/ 1307 if (bh->b_data == b_data + b_allocd) { 1308 bh->b_size += b_allocd; 1309 bh->b_data -= b_allocd; 1310 if (full) 1311 atomic_add(b_allocd, &bh->b_count); 1312 continue; 1313 } 1314 /* they are above the header */ 1315 if (b_data == bh->b_data + bh->b_size) { 1316 bh->b_size += b_allocd; 1317 if (full) 1318 atomic_add(b_allocd, &bh->b_count); 1319 continue; 1320 } 1321 prev_bh = bh; 1322 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1323 if (!bh) { 1324 free_pages((unsigned long) b_data, order); 1325 goto abort; 1326 } 1327 bh->b_reqnext = NULL; 1328 bh->b_data = b_data; 1329 bh->b_size = b_allocd; 1330 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1331 prev_bh->b_reqnext = bh; 1332 1333 pages &= (order-1); 1334 } 1335 1336 bh->b_size -= tape->excess_bh_size; 1337 if (full) 1338 atomic_sub(tape->excess_bh_size, &bh->b_count); 1339 return merge_bh; 1340abort: 1341 ide_tape_kfree_buffer(tape); 1342 return NULL; 1343} 1344 1345static int idetape_copy_stage_from_user(idetape_tape_t *tape, 1346 const char __user *buf, int n) 1347{ 1348 struct idetape_bh *bh = tape->bh; 1349 int count; 1350 int ret = 0; 1351 1352 while (n) { 1353 if (bh == NULL) { 1354 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1355 __func__); 1356 return 1; 1357 } 1358 count = min((unsigned int) 1359 (bh->b_size - atomic_read(&bh->b_count)), 1360 (unsigned int)n); 1361 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 1362 count)) 1363 ret = 1; 1364 n -= count; 1365 atomic_add(count, &bh->b_count); 1366 buf += count; 1367 if (atomic_read(&bh->b_count) == bh->b_size) { 1368 bh = bh->b_reqnext; 1369 if (bh) 1370 atomic_set(&bh->b_count, 0); 1371 } 1372 } 1373 tape->bh = bh; 1374 return ret; 1375} 1376 1377static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1378 int n) 1379{ 1380 struct idetape_bh *bh = tape->bh; 1381 int count; 1382 int ret = 0; 1383 1384 while (n) { 1385 if (bh == NULL) { 1386 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1387 __func__); 1388 return 1; 1389 } 1390 count = min(tape->b_count, n); 1391 if (copy_to_user(buf, tape->b_data, count)) 1392 ret = 1; 1393 n -= count; 1394 tape->b_data += count; 1395 tape->b_count -= count; 1396 buf += count; 1397 if (!tape->b_count) { 1398 bh = bh->b_reqnext; 1399 tape->bh = bh; 1400 if (bh) { 1401 tape->b_data = bh->b_data; 1402 tape->b_count = atomic_read(&bh->b_count); 1403 } 1404 } 1405 } 1406 return ret; 1407} 1408 1409static void idetape_init_merge_buffer(idetape_tape_t *tape) 1410{ 1411 struct idetape_bh *bh = tape->merge_bh; 1412 tape->bh = tape->merge_bh; 1413 1414 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1415 atomic_set(&bh->b_count, 0); 1416 else { 1417 tape->b_data = bh->b_data; 1418 tape->b_count = atomic_read(&bh->b_count); 1419 } 1420} 1421 1422/* 1423 * Write a filemark if write_filemark=1. Flush the device buffers without 1424 * writing a filemark otherwise. 1425 */ 1426static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1427 struct ide_atapi_pc *pc, int write_filemark) 1428{ 1429 idetape_init_pc(pc); 1430 pc->c[0] = WRITE_FILEMARKS; 1431 pc->c[4] = write_filemark; 1432 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1433} 1434 1435static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc) 1436{ 1437 idetape_init_pc(pc); 1438 pc->c[0] = TEST_UNIT_READY; 1439} 1440 1441/* 1442 * We add a special packet command request to the tail of the request queue, and 1443 * wait for it to be serviced. This is not to be called from within the request 1444 * handling part of the driver! We allocate here data on the stack and it is 1445 * valid until the request is finished. This is not the case for the bottom part 1446 * of the driver, where we are always leaving the functions to wait for an 1447 * interrupt or a timer event. 1448 * 1449 * From the bottom part of the driver, we should allocate safe memory using 1450 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request 1451 * to the request list without waiting for it to be serviced! In that case, we 1452 * usually use idetape_queue_pc_head(). 1453 */ 1454static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc) 1455{ 1456 struct ide_tape_obj *tape = drive->driver_data; 1457 struct request *rq; 1458 int error; 1459 1460 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1461 rq->cmd_type = REQ_TYPE_SPECIAL; 1462 rq->cmd[0] = REQ_IDETAPE_PC1; 1463 rq->buffer = (char *)pc; 1464 error = blk_execute_rq(drive->queue, tape->disk, rq, 0); 1465 blk_put_request(rq); 1466 return error; 1467} 1468 1469static void idetape_create_load_unload_cmd(ide_drive_t *drive, 1470 struct ide_atapi_pc *pc, int cmd) 1471{ 1472 idetape_init_pc(pc); 1473 pc->c[0] = START_STOP; 1474 pc->c[4] = cmd; 1475 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1476} 1477 1478static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1479{ 1480 idetape_tape_t *tape = drive->driver_data; 1481 struct ide_atapi_pc pc; 1482 int load_attempted = 0; 1483 1484 /* Wait for the tape to become ready */ 1485 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 1486 timeout += jiffies; 1487 while (time_before(jiffies, timeout)) { 1488 idetape_create_test_unit_ready_cmd(&pc); 1489 if (!idetape_queue_pc_tail(drive, &pc)) 1490 return 0; 1491 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1492 || (tape->asc == 0x3A)) { 1493 /* no media */ 1494 if (load_attempted) 1495 return -ENOMEDIUM; 1496 idetape_create_load_unload_cmd(drive, &pc, 1497 IDETAPE_LU_LOAD_MASK); 1498 idetape_queue_pc_tail(drive, &pc); 1499 load_attempted = 1; 1500 /* not about to be ready */ 1501 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1502 (tape->ascq == 1 || tape->ascq == 8))) 1503 return -EIO; 1504 msleep(100); 1505 } 1506 return -EIO; 1507} 1508 1509static int idetape_flush_tape_buffers(ide_drive_t *drive) 1510{ 1511 struct ide_atapi_pc pc; 1512 int rc; 1513 1514 idetape_create_write_filemark_cmd(drive, &pc, 0); 1515 rc = idetape_queue_pc_tail(drive, &pc); 1516 if (rc) 1517 return rc; 1518 idetape_wait_ready(drive, 60 * 5 * HZ); 1519 return 0; 1520} 1521 1522static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1523{ 1524 idetape_init_pc(pc); 1525 pc->c[0] = READ_POSITION; 1526 pc->req_xfer = 20; 1527} 1528 1529static int idetape_read_position(ide_drive_t *drive) 1530{ 1531 idetape_tape_t *tape = drive->driver_data; 1532 struct ide_atapi_pc pc; 1533 int position; 1534 1535 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1536 1537 idetape_create_read_position_cmd(&pc); 1538 if (idetape_queue_pc_tail(drive, &pc)) 1539 return -1; 1540 position = tape->first_frame; 1541 return position; 1542} 1543 1544static void idetape_create_locate_cmd(ide_drive_t *drive, 1545 struct ide_atapi_pc *pc, 1546 unsigned int block, u8 partition, int skip) 1547{ 1548 idetape_init_pc(pc); 1549 pc->c[0] = POSITION_TO_ELEMENT; 1550 pc->c[1] = 2; 1551 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1552 pc->c[8] = partition; 1553 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1554} 1555 1556static int idetape_create_prevent_cmd(ide_drive_t *drive, 1557 struct ide_atapi_pc *pc, int prevent) 1558{ 1559 idetape_tape_t *tape = drive->driver_data; 1560 1561 /* device supports locking according to capabilities page */ 1562 if (!(tape->caps[6] & 0x01)) 1563 return 0; 1564 1565 idetape_init_pc(pc); 1566 pc->c[0] = ALLOW_MEDIUM_REMOVAL; 1567 pc->c[4] = prevent; 1568 return 1; 1569} 1570 1571static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1572{ 1573 idetape_tape_t *tape = drive->driver_data; 1574 1575 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1576 return; 1577 1578 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags); 1579 tape->merge_bh_size = 0; 1580 if (tape->merge_bh != NULL) { 1581 ide_tape_kfree_buffer(tape); 1582 tape->merge_bh = NULL; 1583 } 1584 1585 tape->chrdev_dir = IDETAPE_DIR_NONE; 1586} 1587 1588/* 1589 * Position the tape to the requested block using the LOCATE packet command. 1590 * A READ POSITION command is then issued to check where we are positioned. Like 1591 * all higher level operations, we queue the commands at the tail of the request 1592 * queue and wait for their completion. 1593 */ 1594static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1595 u8 partition, int skip) 1596{ 1597 idetape_tape_t *tape = drive->driver_data; 1598 int retval; 1599 struct ide_atapi_pc pc; 1600 1601 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1602 __ide_tape_discard_merge_buffer(drive); 1603 idetape_wait_ready(drive, 60 * 5 * HZ); 1604 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1605 retval = idetape_queue_pc_tail(drive, &pc); 1606 if (retval) 1607 return (retval); 1608 1609 idetape_create_read_position_cmd(&pc); 1610 return (idetape_queue_pc_tail(drive, &pc)); 1611} 1612 1613static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1614 int restore_position) 1615{ 1616 idetape_tape_t *tape = drive->driver_data; 1617 int seek, position; 1618 1619 __ide_tape_discard_merge_buffer(drive); 1620 if (restore_position) { 1621 position = idetape_read_position(drive); 1622 seek = position > 0 ? position : 0; 1623 if (idetape_position_tape(drive, seek, 0, 0)) { 1624 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1625 " %s\n", tape->name, __func__); 1626 return; 1627 } 1628 } 1629} 1630 1631/* 1632 * Generate a read/write request for the block device interface and wait for it 1633 * to be serviced. 1634 */ 1635static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1636 struct idetape_bh *bh) 1637{ 1638 idetape_tape_t *tape = drive->driver_data; 1639 struct request *rq; 1640 int ret, errors; 1641 1642 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1643 1644 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1645 rq->cmd_type = REQ_TYPE_SPECIAL; 1646 rq->cmd[0] = cmd; 1647 rq->rq_disk = tape->disk; 1648 rq->special = (void *)bh; 1649 rq->sector = tape->first_frame; 1650 rq->nr_sectors = blocks; 1651 rq->current_nr_sectors = blocks; 1652 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1653 1654 errors = rq->errors; 1655 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1656 blk_put_request(rq); 1657 1658 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1659 return 0; 1660 1661 if (tape->merge_bh) 1662 idetape_init_merge_buffer(tape); 1663 if (errors == IDETAPE_ERROR_GENERAL) 1664 return -EIO; 1665 return ret; 1666} 1667 1668static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1669{ 1670 idetape_init_pc(pc); 1671 pc->c[0] = INQUIRY; 1672 pc->c[4] = 254; 1673 pc->req_xfer = 254; 1674} 1675 1676static void idetape_create_rewind_cmd(ide_drive_t *drive, 1677 struct ide_atapi_pc *pc) 1678{ 1679 idetape_init_pc(pc); 1680 pc->c[0] = REZERO_UNIT; 1681 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1682} 1683 1684static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1685{ 1686 idetape_init_pc(pc); 1687 pc->c[0] = ERASE; 1688 pc->c[1] = 1; 1689 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1690} 1691 1692static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1693{ 1694 idetape_init_pc(pc); 1695 pc->c[0] = SPACE; 1696 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1697 pc->c[1] = cmd; 1698 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1699} 1700 1701/* Queue up a character device originated write request. */ 1702static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1703{ 1704 idetape_tape_t *tape = drive->driver_data; 1705 1706 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1707 1708 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1709 blocks, tape->merge_bh); 1710} 1711 1712static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1713{ 1714 idetape_tape_t *tape = drive->driver_data; 1715 int blocks, min; 1716 struct idetape_bh *bh; 1717 1718 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1719 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1720 " but we are not writing.\n"); 1721 return; 1722 } 1723 if (tape->merge_bh_size > tape->buffer_size) { 1724 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1725 tape->merge_bh_size = tape->buffer_size; 1726 } 1727 if (tape->merge_bh_size) { 1728 blocks = tape->merge_bh_size / tape->blk_size; 1729 if (tape->merge_bh_size % tape->blk_size) { 1730 unsigned int i; 1731 1732 blocks++; 1733 i = tape->blk_size - tape->merge_bh_size % 1734 tape->blk_size; 1735 bh = tape->bh->b_reqnext; 1736 while (bh) { 1737 atomic_set(&bh->b_count, 0); 1738 bh = bh->b_reqnext; 1739 } 1740 bh = tape->bh; 1741 while (i) { 1742 if (bh == NULL) { 1743 printk(KERN_INFO "ide-tape: bug," 1744 " bh NULL\n"); 1745 break; 1746 } 1747 min = min(i, (unsigned int)(bh->b_size - 1748 atomic_read(&bh->b_count))); 1749 memset(bh->b_data + atomic_read(&bh->b_count), 1750 0, min); 1751 atomic_add(min, &bh->b_count); 1752 i -= min; 1753 bh = bh->b_reqnext; 1754 } 1755 } 1756 (void) idetape_add_chrdev_write_request(drive, blocks); 1757 tape->merge_bh_size = 0; 1758 } 1759 if (tape->merge_bh != NULL) { 1760 ide_tape_kfree_buffer(tape); 1761 tape->merge_bh = NULL; 1762 } 1763 tape->chrdev_dir = IDETAPE_DIR_NONE; 1764} 1765 1766static int idetape_init_read(ide_drive_t *drive) 1767{ 1768 idetape_tape_t *tape = drive->driver_data; 1769 int bytes_read; 1770 1771 /* Initialize read operation */ 1772 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1773 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1774 ide_tape_flush_merge_buffer(drive); 1775 idetape_flush_tape_buffers(drive); 1776 } 1777 if (tape->merge_bh || tape->merge_bh_size) { 1778 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1779 " 0 now\n"); 1780 tape->merge_bh_size = 0; 1781 } 1782 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1783 if (!tape->merge_bh) 1784 return -ENOMEM; 1785 tape->chrdev_dir = IDETAPE_DIR_READ; 1786 1787 /* 1788 * Issue a read 0 command to ensure that DSC handshake is 1789 * switched from completion mode to buffer available mode. 1790 * No point in issuing this if DSC overlap isn't supported, some 1791 * drives (Seagate STT3401A) will return an error. 1792 */ 1793 if (drive->dsc_overlap) { 1794 bytes_read = idetape_queue_rw_tail(drive, 1795 REQ_IDETAPE_READ, 0, 1796 tape->merge_bh); 1797 if (bytes_read < 0) { 1798 ide_tape_kfree_buffer(tape); 1799 tape->merge_bh = NULL; 1800 tape->chrdev_dir = IDETAPE_DIR_NONE; 1801 return bytes_read; 1802 } 1803 } 1804 } 1805 1806 return 0; 1807} 1808 1809/* called from idetape_chrdev_read() to service a chrdev read request. */ 1810static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1811{ 1812 idetape_tape_t *tape = drive->driver_data; 1813 1814 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1815 1816 /* If we are at a filemark, return a read length of 0 */ 1817 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1818 return 0; 1819 1820 idetape_init_read(drive); 1821 1822 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1823 tape->merge_bh); 1824} 1825 1826static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1827{ 1828 idetape_tape_t *tape = drive->driver_data; 1829 struct idetape_bh *bh; 1830 int blocks; 1831 1832 while (bcount) { 1833 unsigned int count; 1834 1835 bh = tape->merge_bh; 1836 count = min(tape->buffer_size, bcount); 1837 bcount -= count; 1838 blocks = count / tape->blk_size; 1839 while (count) { 1840 atomic_set(&bh->b_count, 1841 min(count, (unsigned int)bh->b_size)); 1842 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1843 count -= atomic_read(&bh->b_count); 1844 bh = bh->b_reqnext; 1845 } 1846 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1847 tape->merge_bh); 1848 } 1849} 1850 1851/* 1852 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1853 * currently support only one partition. 1854 */ 1855static int idetape_rewind_tape(ide_drive_t *drive) 1856{ 1857 int retval; 1858 struct ide_atapi_pc pc; 1859 idetape_tape_t *tape; 1860 tape = drive->driver_data; 1861 1862 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1863 1864 idetape_create_rewind_cmd(drive, &pc); 1865 retval = idetape_queue_pc_tail(drive, &pc); 1866 if (retval) 1867 return retval; 1868 1869 idetape_create_read_position_cmd(&pc); 1870 retval = idetape_queue_pc_tail(drive, &pc); 1871 if (retval) 1872 return retval; 1873 return 0; 1874} 1875 1876/* mtio.h compatible commands should be issued to the chrdev interface. */ 1877static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1878 unsigned long arg) 1879{ 1880 idetape_tape_t *tape = drive->driver_data; 1881 void __user *argp = (void __user *)arg; 1882 1883 struct idetape_config { 1884 int dsc_rw_frequency; 1885 int dsc_media_access_frequency; 1886 int nr_stages; 1887 } config; 1888 1889 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1890 1891 switch (cmd) { 1892 case 0x0340: 1893 if (copy_from_user(&config, argp, sizeof(config))) 1894 return -EFAULT; 1895 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1896 break; 1897 case 0x0350: 1898 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1899 config.nr_stages = 1; 1900 if (copy_to_user(argp, &config, sizeof(config))) 1901 return -EFAULT; 1902 break; 1903 default: 1904 return -EIO; 1905 } 1906 return 0; 1907} 1908 1909static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1910 int mt_count) 1911{ 1912 idetape_tape_t *tape = drive->driver_data; 1913 struct ide_atapi_pc pc; 1914 int retval, count = 0; 1915 int sprev = !!(tape->caps[4] & 0x20); 1916 1917 if (mt_count == 0) 1918 return 0; 1919 if (MTBSF == mt_op || MTBSFM == mt_op) { 1920 if (!sprev) 1921 return -EIO; 1922 mt_count = -mt_count; 1923 } 1924 1925 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1926 tape->merge_bh_size = 0; 1927 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1928 ++count; 1929 ide_tape_discard_merge_buffer(drive, 0); 1930 } 1931 1932 switch (mt_op) { 1933 case MTFSF: 1934 case MTBSF: 1935 idetape_create_space_cmd(&pc, mt_count - count, 1936 IDETAPE_SPACE_OVER_FILEMARK); 1937 return idetape_queue_pc_tail(drive, &pc); 1938 case MTFSFM: 1939 case MTBSFM: 1940 if (!sprev) 1941 return -EIO; 1942 retval = idetape_space_over_filemarks(drive, MTFSF, 1943 mt_count - count); 1944 if (retval) 1945 return retval; 1946 count = (MTBSFM == mt_op ? 1 : -1); 1947 return idetape_space_over_filemarks(drive, MTFSF, count); 1948 default: 1949 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1950 mt_op); 1951 return -EIO; 1952 } 1953} 1954 1955/* 1956 * Our character device read / write functions. 1957 * 1958 * The tape is optimized to maximize throughput when it is transferring an 1959 * integral number of the "continuous transfer limit", which is a parameter of 1960 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1961 * 1962 * As of version 1.3 of the driver, the character device provides an abstract 1963 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1964 * same backup/restore procedure is supported. The driver will internally 1965 * convert the requests to the recommended transfer unit, so that an unmatch 1966 * between the user's block size to the recommended size will only result in a 1967 * (slightly) increased driver overhead, but will no longer hit performance. 1968 * This is not applicable to Onstream. 1969 */ 1970static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1971 size_t count, loff_t *ppos) 1972{ 1973 struct ide_tape_obj *tape = ide_tape_f(file); 1974 ide_drive_t *drive = tape->drive; 1975 ssize_t bytes_read, temp, actually_read = 0, rc; 1976 ssize_t ret = 0; 1977 u16 ctl = *(u16 *)&tape->caps[12]; 1978 1979 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1980 1981 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1982 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags)) 1983 if (count > tape->blk_size && 1984 (count % tape->blk_size) == 0) 1985 tape->user_bs_factor = count / tape->blk_size; 1986 } 1987 rc = idetape_init_read(drive); 1988 if (rc < 0) 1989 return rc; 1990 if (count == 0) 1991 return (0); 1992 if (tape->merge_bh_size) { 1993 actually_read = min((unsigned int)(tape->merge_bh_size), 1994 (unsigned int)count); 1995 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1996 ret = -EFAULT; 1997 buf += actually_read; 1998 tape->merge_bh_size -= actually_read; 1999 count -= actually_read; 2000 } 2001 while (count >= tape->buffer_size) { 2002 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2003 if (bytes_read <= 0) 2004 goto finish; 2005 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 2006 ret = -EFAULT; 2007 buf += bytes_read; 2008 count -= bytes_read; 2009 actually_read += bytes_read; 2010 } 2011 if (count) { 2012 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2013 if (bytes_read <= 0) 2014 goto finish; 2015 temp = min((unsigned long)count, (unsigned long)bytes_read); 2016 if (idetape_copy_stage_to_user(tape, buf, temp)) 2017 ret = -EFAULT; 2018 actually_read += temp; 2019 tape->merge_bh_size = bytes_read-temp; 2020 } 2021finish: 2022 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) { 2023 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 2024 2025 idetape_space_over_filemarks(drive, MTFSF, 1); 2026 return 0; 2027 } 2028 2029 return ret ? ret : actually_read; 2030} 2031 2032static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 2033 size_t count, loff_t *ppos) 2034{ 2035 struct ide_tape_obj *tape = ide_tape_f(file); 2036 ide_drive_t *drive = tape->drive; 2037 ssize_t actually_written = 0; 2038 ssize_t ret = 0; 2039 u16 ctl = *(u16 *)&tape->caps[12]; 2040 2041 /* The drive is write protected. */ 2042 if (tape->write_prot) 2043 return -EACCES; 2044 2045 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 2046 2047 /* Initialize write operation */ 2048 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 2049 if (tape->chrdev_dir == IDETAPE_DIR_READ) 2050 ide_tape_discard_merge_buffer(drive, 1); 2051 if (tape->merge_bh || tape->merge_bh_size) { 2052 printk(KERN_ERR "ide-tape: merge_bh_size " 2053 "should be 0 now\n"); 2054 tape->merge_bh_size = 0; 2055 } 2056 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 2057 if (!tape->merge_bh) 2058 return -ENOMEM; 2059 tape->chrdev_dir = IDETAPE_DIR_WRITE; 2060 idetape_init_merge_buffer(tape); 2061 2062 /* 2063 * Issue a write 0 command to ensure that DSC handshake is 2064 * switched from completion mode to buffer available mode. No 2065 * point in issuing this if DSC overlap isn't supported, some 2066 * drives (Seagate STT3401A) will return an error. 2067 */ 2068 if (drive->dsc_overlap) { 2069 ssize_t retval = idetape_queue_rw_tail(drive, 2070 REQ_IDETAPE_WRITE, 0, 2071 tape->merge_bh); 2072 if (retval < 0) { 2073 ide_tape_kfree_buffer(tape); 2074 tape->merge_bh = NULL; 2075 tape->chrdev_dir = IDETAPE_DIR_NONE; 2076 return retval; 2077 } 2078 } 2079 } 2080 if (count == 0) 2081 return (0); 2082 if (tape->merge_bh_size) { 2083 if (tape->merge_bh_size >= tape->buffer_size) { 2084 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 2085 tape->merge_bh_size = 0; 2086 } 2087 actually_written = min((unsigned int) 2088 (tape->buffer_size - tape->merge_bh_size), 2089 (unsigned int)count); 2090 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 2091 ret = -EFAULT; 2092 buf += actually_written; 2093 tape->merge_bh_size += actually_written; 2094 count -= actually_written; 2095 2096 if (tape->merge_bh_size == tape->buffer_size) { 2097 ssize_t retval; 2098 tape->merge_bh_size = 0; 2099 retval = idetape_add_chrdev_write_request(drive, ctl); 2100 if (retval <= 0) 2101 return (retval); 2102 } 2103 } 2104 while (count >= tape->buffer_size) { 2105 ssize_t retval; 2106 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 2107 ret = -EFAULT; 2108 buf += tape->buffer_size; 2109 count -= tape->buffer_size; 2110 retval = idetape_add_chrdev_write_request(drive, ctl); 2111 actually_written += tape->buffer_size; 2112 if (retval <= 0) 2113 return (retval); 2114 } 2115 if (count) { 2116 actually_written += count; 2117 if (idetape_copy_stage_from_user(tape, buf, count)) 2118 ret = -EFAULT; 2119 tape->merge_bh_size += count; 2120 } 2121 return ret ? ret : actually_written; 2122} 2123 2124static int idetape_write_filemark(ide_drive_t *drive) 2125{ 2126 struct ide_atapi_pc pc; 2127 2128 /* Write a filemark */ 2129 idetape_create_write_filemark_cmd(drive, &pc, 1); 2130 if (idetape_queue_pc_tail(drive, &pc)) { 2131 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 2132 return -EIO; 2133 } 2134 return 0; 2135} 2136 2137/* 2138 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 2139 * requested. 2140 * 2141 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 2142 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 2143 * usually not supported. 2144 * 2145 * The following commands are currently not supported: 2146 * 2147 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 2148 * MT_ST_WRITE_THRESHOLD. 2149 */ 2150static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 2151{ 2152 idetape_tape_t *tape = drive->driver_data; 2153 struct ide_atapi_pc pc; 2154 int i, retval; 2155 2156 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 2157 mt_op, mt_count); 2158 2159 switch (mt_op) { 2160 case MTFSF: 2161 case MTFSFM: 2162 case MTBSF: 2163 case MTBSFM: 2164 if (!mt_count) 2165 return 0; 2166 return idetape_space_over_filemarks(drive, mt_op, mt_count); 2167 default: 2168 break; 2169 } 2170 2171 switch (mt_op) { 2172 case MTWEOF: 2173 if (tape->write_prot) 2174 return -EACCES; 2175 ide_tape_discard_merge_buffer(drive, 1); 2176 for (i = 0; i < mt_count; i++) { 2177 retval = idetape_write_filemark(drive); 2178 if (retval) 2179 return retval; 2180 } 2181 return 0; 2182 case MTREW: 2183 ide_tape_discard_merge_buffer(drive, 0); 2184 if (idetape_rewind_tape(drive)) 2185 return -EIO; 2186 return 0; 2187 case MTLOAD: 2188 ide_tape_discard_merge_buffer(drive, 0); 2189 idetape_create_load_unload_cmd(drive, &pc, 2190 IDETAPE_LU_LOAD_MASK); 2191 return idetape_queue_pc_tail(drive, &pc); 2192 case MTUNLOAD: 2193 case MTOFFL: 2194 /* 2195 * If door is locked, attempt to unlock before 2196 * attempting to eject. 2197 */ 2198 if (tape->door_locked) { 2199 if (idetape_create_prevent_cmd(drive, &pc, 0)) 2200 if (!idetape_queue_pc_tail(drive, &pc)) 2201 tape->door_locked = DOOR_UNLOCKED; 2202 } 2203 ide_tape_discard_merge_buffer(drive, 0); 2204 idetape_create_load_unload_cmd(drive, &pc, 2205 !IDETAPE_LU_LOAD_MASK); 2206 retval = idetape_queue_pc_tail(drive, &pc); 2207 if (!retval) 2208 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 2209 return retval; 2210 case MTNOP: 2211 ide_tape_discard_merge_buffer(drive, 0); 2212 return idetape_flush_tape_buffers(drive); 2213 case MTRETEN: 2214 ide_tape_discard_merge_buffer(drive, 0); 2215 idetape_create_load_unload_cmd(drive, &pc, 2216 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 2217 return idetape_queue_pc_tail(drive, &pc); 2218 case MTEOM: 2219 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 2220 return idetape_queue_pc_tail(drive, &pc); 2221 case MTERASE: 2222 (void)idetape_rewind_tape(drive); 2223 idetape_create_erase_cmd(&pc); 2224 return idetape_queue_pc_tail(drive, &pc); 2225 case MTSETBLK: 2226 if (mt_count) { 2227 if (mt_count < tape->blk_size || 2228 mt_count % tape->blk_size) 2229 return -EIO; 2230 tape->user_bs_factor = mt_count / tape->blk_size; 2231 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2232 } else 2233 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2234 return 0; 2235 case MTSEEK: 2236 ide_tape_discard_merge_buffer(drive, 0); 2237 return idetape_position_tape(drive, 2238 mt_count * tape->user_bs_factor, tape->partition, 0); 2239 case MTSETPART: 2240 ide_tape_discard_merge_buffer(drive, 0); 2241 return idetape_position_tape(drive, 0, mt_count, 0); 2242 case MTFSR: 2243 case MTBSR: 2244 case MTLOCK: 2245 if (!idetape_create_prevent_cmd(drive, &pc, 1)) 2246 return 0; 2247 retval = idetape_queue_pc_tail(drive, &pc); 2248 if (retval) 2249 return retval; 2250 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 2251 return 0; 2252 case MTUNLOCK: 2253 if (!idetape_create_prevent_cmd(drive, &pc, 0)) 2254 return 0; 2255 retval = idetape_queue_pc_tail(drive, &pc); 2256 if (retval) 2257 return retval; 2258 tape->door_locked = DOOR_UNLOCKED; 2259 return 0; 2260 default: 2261 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 2262 mt_op); 2263 return -EIO; 2264 } 2265} 2266 2267/* 2268 * Our character device ioctls. General mtio.h magnetic io commands are 2269 * supported here, and not in the corresponding block interface. Our own 2270 * ide-tape ioctls are supported on both interfaces. 2271 */ 2272static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 2273 unsigned int cmd, unsigned long arg) 2274{ 2275 struct ide_tape_obj *tape = ide_tape_f(file); 2276 ide_drive_t *drive = tape->drive; 2277 struct mtop mtop; 2278 struct mtget mtget; 2279 struct mtpos mtpos; 2280 int block_offset = 0, position = tape->first_frame; 2281 void __user *argp = (void __user *)arg; 2282 2283 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 2284 2285 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 2286 ide_tape_flush_merge_buffer(drive); 2287 idetape_flush_tape_buffers(drive); 2288 } 2289 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 2290 block_offset = tape->merge_bh_size / 2291 (tape->blk_size * tape->user_bs_factor); 2292 position = idetape_read_position(drive); 2293 if (position < 0) 2294 return -EIO; 2295 } 2296 switch (cmd) { 2297 case MTIOCTOP: 2298 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 2299 return -EFAULT; 2300 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 2301 case MTIOCGET: 2302 memset(&mtget, 0, sizeof(struct mtget)); 2303 mtget.mt_type = MT_ISSCSI2; 2304 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 2305 mtget.mt_dsreg = 2306 ((tape->blk_size * tape->user_bs_factor) 2307 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 2308 2309 if (tape->drv_write_prot) 2310 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 2311 2312 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 2313 return -EFAULT; 2314 return 0; 2315 case MTIOCPOS: 2316 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 2317 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 2318 return -EFAULT; 2319 return 0; 2320 default: 2321 if (tape->chrdev_dir == IDETAPE_DIR_READ) 2322 ide_tape_discard_merge_buffer(drive, 1); 2323 return idetape_blkdev_ioctl(drive, cmd, arg); 2324 } 2325} 2326 2327/* 2328 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 2329 * block size with the reported value. 2330 */ 2331static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 2332{ 2333 idetape_tape_t *tape = drive->driver_data; 2334 struct ide_atapi_pc pc; 2335 2336 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 2337 if (idetape_queue_pc_tail(drive, &pc)) { 2338 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 2339 if (tape->blk_size == 0) { 2340 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 2341 "block size, assuming 32k\n"); 2342 tape->blk_size = 32768; 2343 } 2344 return; 2345 } 2346 tape->blk_size = (pc.buf[4 + 5] << 16) + 2347 (pc.buf[4 + 6] << 8) + 2348 pc.buf[4 + 7]; 2349 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 2350} 2351 2352static int idetape_chrdev_open(struct inode *inode, struct file *filp) 2353{ 2354 unsigned int minor = iminor(inode), i = minor & ~0xc0; 2355 ide_drive_t *drive; 2356 idetape_tape_t *tape; 2357 struct ide_atapi_pc pc; 2358 int retval; 2359 2360 if (i >= MAX_HWIFS * MAX_DRIVES) 2361 return -ENXIO; 2362 2363 tape = ide_tape_chrdev_get(i); 2364 if (!tape) 2365 return -ENXIO; 2366 2367 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2368 2369 /* 2370 * We really want to do nonseekable_open(inode, filp); here, but some 2371 * versions of tar incorrectly call lseek on tapes and bail out if that 2372 * fails. So we disallow pread() and pwrite(), but permit lseeks. 2373 */ 2374 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 2375 2376 drive = tape->drive; 2377 2378 filp->private_data = tape; 2379 2380 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) { 2381 retval = -EBUSY; 2382 goto out_put_tape; 2383 } 2384 2385 retval = idetape_wait_ready(drive, 60 * HZ); 2386 if (retval) { 2387 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2388 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 2389 goto out_put_tape; 2390 } 2391 2392 idetape_read_position(drive); 2393 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags)) 2394 (void)idetape_rewind_tape(drive); 2395 2396 /* Read block size and write protect status from drive. */ 2397 ide_tape_get_bsize_from_bdesc(drive); 2398 2399 /* Set write protect flag if device is opened as read-only. */ 2400 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 2401 tape->write_prot = 1; 2402 else 2403 tape->write_prot = tape->drv_write_prot; 2404 2405 /* Make sure drive isn't write protected if user wants to write. */ 2406 if (tape->write_prot) { 2407 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 2408 (filp->f_flags & O_ACCMODE) == O_RDWR) { 2409 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2410 retval = -EROFS; 2411 goto out_put_tape; 2412 } 2413 } 2414 2415 /* Lock the tape drive door so user can't eject. */ 2416 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2417 if (idetape_create_prevent_cmd(drive, &pc, 1)) { 2418 if (!idetape_queue_pc_tail(drive, &pc)) { 2419 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 2420 tape->door_locked = DOOR_LOCKED; 2421 } 2422 } 2423 } 2424 return 0; 2425 2426out_put_tape: 2427 ide_tape_put(tape); 2428 return retval; 2429} 2430 2431static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 2432{ 2433 idetape_tape_t *tape = drive->driver_data; 2434 2435 ide_tape_flush_merge_buffer(drive); 2436 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 2437 if (tape->merge_bh != NULL) { 2438 idetape_pad_zeros(drive, tape->blk_size * 2439 (tape->user_bs_factor - 1)); 2440 ide_tape_kfree_buffer(tape); 2441 tape->merge_bh = NULL; 2442 } 2443 idetape_write_filemark(drive); 2444 idetape_flush_tape_buffers(drive); 2445 idetape_flush_tape_buffers(drive); 2446} 2447 2448static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2449{ 2450 struct ide_tape_obj *tape = ide_tape_f(filp); 2451 ide_drive_t *drive = tape->drive; 2452 struct ide_atapi_pc pc; 2453 unsigned int minor = iminor(inode); 2454 2455 lock_kernel(); 2456 tape = drive->driver_data; 2457 2458 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2459 2460 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2461 idetape_write_release(drive, minor); 2462 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2463 if (minor < 128) 2464 ide_tape_discard_merge_buffer(drive, 1); 2465 } 2466 2467 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags)) 2468 (void) idetape_rewind_tape(drive); 2469 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2470 if (tape->door_locked == DOOR_LOCKED) { 2471 if (idetape_create_prevent_cmd(drive, &pc, 0)) { 2472 if (!idetape_queue_pc_tail(drive, &pc)) 2473 tape->door_locked = DOOR_UNLOCKED; 2474 } 2475 } 2476 } 2477 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2478 ide_tape_put(tape); 2479 unlock_kernel(); 2480 return 0; 2481} 2482 2483/* 2484 * check the contents of the ATAPI IDENTIFY command results. We return: 2485 * 2486 * 1 - If the tape can be supported by us, based on the information we have so 2487 * far. 2488 * 2489 * 0 - If this tape driver is not currently supported by us. 2490 */ 2491static int idetape_identify_device(ide_drive_t *drive) 2492{ 2493 u8 gcw[2], protocol, device_type, removable, packet_size; 2494 2495 if (drive->id_read == 0) 2496 return 1; 2497 2498 *((unsigned short *) &gcw) = drive->id->config; 2499 2500 protocol = (gcw[1] & 0xC0) >> 6; 2501 device_type = gcw[1] & 0x1F; 2502 removable = !!(gcw[0] & 0x80); 2503 packet_size = gcw[0] & 0x3; 2504 2505 /* Check that we can support this device */ 2506 if (protocol != 2) 2507 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n", 2508 protocol); 2509 else if (device_type != 1) 2510 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set " 2511 "to tape\n", device_type); 2512 else if (!removable) 2513 printk(KERN_ERR "ide-tape: The removable flag is not set\n"); 2514 else if (packet_size != 0) { 2515 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12" 2516 " bytes\n", packet_size); 2517 } else 2518 return 1; 2519 return 0; 2520} 2521 2522static void idetape_get_inquiry_results(ide_drive_t *drive) 2523{ 2524 idetape_tape_t *tape = drive->driver_data; 2525 struct ide_atapi_pc pc; 2526 char fw_rev[6], vendor_id[10], product_id[18]; 2527 2528 idetape_create_inquiry_cmd(&pc); 2529 if (idetape_queue_pc_tail(drive, &pc)) { 2530 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2531 tape->name); 2532 return; 2533 } 2534 memcpy(vendor_id, &pc.buf[8], 8); 2535 memcpy(product_id, &pc.buf[16], 16); 2536 memcpy(fw_rev, &pc.buf[32], 4); 2537 2538 ide_fixstring(vendor_id, 10, 0); 2539 ide_fixstring(product_id, 18, 0); 2540 ide_fixstring(fw_rev, 6, 0); 2541 2542 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n", 2543 drive->name, tape->name, vendor_id, product_id, fw_rev); 2544} 2545 2546/* 2547 * Ask the tape about its various parameters. In particular, we will adjust our 2548 * data transfer buffer size to the recommended value as returned by the tape. 2549 */ 2550static void idetape_get_mode_sense_results(ide_drive_t *drive) 2551{ 2552 idetape_tape_t *tape = drive->driver_data; 2553 struct ide_atapi_pc pc; 2554 u8 *caps; 2555 u8 speed, max_speed; 2556 2557 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2558 if (idetape_queue_pc_tail(drive, &pc)) { 2559 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2560 " some default values\n"); 2561 tape->blk_size = 512; 2562 put_unaligned(52, (u16 *)&tape->caps[12]); 2563 put_unaligned(540, (u16 *)&tape->caps[14]); 2564 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2565 return; 2566 } 2567 caps = pc.buf + 4 + pc.buf[3]; 2568 2569 /* convert to host order and save for later use */ 2570 speed = be16_to_cpu(*(u16 *)&caps[14]); 2571 max_speed = be16_to_cpu(*(u16 *)&caps[8]); 2572 2573 put_unaligned(max_speed, (u16 *)&caps[8]); 2574 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]); 2575 put_unaligned(speed, (u16 *)&caps[14]); 2576 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]); 2577 2578 if (!speed) { 2579 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2580 "(assuming 650KB/sec)\n", drive->name); 2581 put_unaligned(650, (u16 *)&caps[14]); 2582 } 2583 if (!max_speed) { 2584 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2585 "(assuming 650KB/sec)\n", drive->name); 2586 put_unaligned(650, (u16 *)&caps[8]); 2587 } 2588 2589 memcpy(&tape->caps, caps, 20); 2590 if (caps[7] & 0x02) 2591 tape->blk_size = 512; 2592 else if (caps[7] & 0x04) 2593 tape->blk_size = 1024; 2594} 2595 2596#ifdef CONFIG_IDE_PROC_FS 2597static void idetape_add_settings(ide_drive_t *drive) 2598{ 2599 idetape_tape_t *tape = drive->driver_data; 2600 2601 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2602 1, 2, (u16 *)&tape->caps[16], NULL); 2603 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2604 1, 1, (u16 *)&tape->caps[14], NULL); 2605 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff, 2606 1, 1024, &tape->buffer_size, NULL); 2607 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN, 2608 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq, 2609 NULL); 2610 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1, 2611 1, &drive->dsc_overlap, NULL); 2612 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff, 2613 1, 1, &tape->avg_speed, NULL); 2614 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1, 2615 1, &tape->debug_mask, NULL); 2616} 2617#else 2618static inline void idetape_add_settings(ide_drive_t *drive) { ; } 2619#endif 2620 2621/* 2622 * The function below is called to: 2623 * 2624 * 1. Initialize our various state variables. 2625 * 2. Ask the tape for its capabilities. 2626 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2627 * is chosen based on the recommendation which we received in step 2. 2628 * 2629 * Note that at this point ide.c already assigned us an irq, so that we can 2630 * queue requests here and wait for their completion. 2631 */ 2632static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2633{ 2634 unsigned long t; 2635 int speed; 2636 int buffer_size; 2637 u8 gcw[2]; 2638 u16 *ctl = (u16 *)&tape->caps[12]; 2639 2640 spin_lock_init(&tape->lock); 2641 drive->dsc_overlap = 1; 2642 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2643 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2644 tape->name); 2645 drive->dsc_overlap = 0; 2646 } 2647 /* Seagate Travan drives do not support DSC overlap. */ 2648 if (strstr(drive->id->model, "Seagate STT3401")) 2649 drive->dsc_overlap = 0; 2650 tape->minor = minor; 2651 tape->name[0] = 'h'; 2652 tape->name[1] = 't'; 2653 tape->name[2] = '0' + minor; 2654 tape->chrdev_dir = IDETAPE_DIR_NONE; 2655 tape->pc = tape->pc_stack; 2656 *((unsigned short *) &gcw) = drive->id->config; 2657 2658 /* Command packet DRQ type */ 2659 if (((gcw[0] & 0x60) >> 5) == 1) 2660 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags); 2661 2662 idetape_get_inquiry_results(drive); 2663 idetape_get_mode_sense_results(drive); 2664 ide_tape_get_bsize_from_bdesc(drive); 2665 tape->user_bs_factor = 1; 2666 tape->buffer_size = *ctl * tape->blk_size; 2667 while (tape->buffer_size > 0xffff) { 2668 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2669 *ctl /= 2; 2670 tape->buffer_size = *ctl * tape->blk_size; 2671 } 2672 buffer_size = tape->buffer_size; 2673 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2674 if (buffer_size % PAGE_SIZE) { 2675 tape->pages_per_buffer++; 2676 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2677 } 2678 2679 /* select the "best" DSC read/write polling freq */ 2680 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2681 2682 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2683 2684 /* 2685 * Ensure that the number we got makes sense; limit it within 2686 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2687 */ 2688 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2689 IDETAPE_DSC_RW_MAX); 2690 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2691 "%lums tDSC%s\n", 2692 drive->name, tape->name, *(u16 *)&tape->caps[14], 2693 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2694 tape->buffer_size / 1024, 2695 tape->best_dsc_rw_freq * 1000 / HZ, 2696 drive->using_dma ? ", DMA":""); 2697 2698 idetape_add_settings(drive); 2699} 2700 2701static void ide_tape_remove(ide_drive_t *drive) 2702{ 2703 idetape_tape_t *tape = drive->driver_data; 2704 2705 ide_proc_unregister_driver(drive, tape->driver); 2706 2707 ide_unregister_region(tape->disk); 2708 2709 ide_tape_put(tape); 2710} 2711 2712static void ide_tape_release(struct kref *kref) 2713{ 2714 struct ide_tape_obj *tape = to_ide_tape(kref); 2715 ide_drive_t *drive = tape->drive; 2716 struct gendisk *g = tape->disk; 2717 2718 BUG_ON(tape->merge_bh_size); 2719 2720 drive->dsc_overlap = 0; 2721 drive->driver_data = NULL; 2722 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2723 device_destroy(idetape_sysfs_class, 2724 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2725 idetape_devs[tape->minor] = NULL; 2726 g->private_data = NULL; 2727 put_disk(g); 2728 kfree(tape); 2729} 2730 2731#ifdef CONFIG_IDE_PROC_FS 2732static int proc_idetape_read_name 2733 (char *page, char **start, off_t off, int count, int *eof, void *data) 2734{ 2735 ide_drive_t *drive = (ide_drive_t *) data; 2736 idetape_tape_t *tape = drive->driver_data; 2737 char *out = page; 2738 int len; 2739 2740 len = sprintf(out, "%s\n", tape->name); 2741 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2742} 2743 2744static ide_proc_entry_t idetape_proc[] = { 2745 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2746 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2747 { NULL, 0, NULL, NULL } 2748}; 2749#endif 2750 2751static int ide_tape_probe(ide_drive_t *); 2752 2753static ide_driver_t idetape_driver = { 2754 .gen_driver = { 2755 .owner = THIS_MODULE, 2756 .name = "ide-tape", 2757 .bus = &ide_bus_type, 2758 }, 2759 .probe = ide_tape_probe, 2760 .remove = ide_tape_remove, 2761 .version = IDETAPE_VERSION, 2762 .media = ide_tape, 2763 .supports_dsc_overlap = 1, 2764 .do_request = idetape_do_request, 2765 .end_request = idetape_end_request, 2766 .error = __ide_error, 2767 .abort = __ide_abort, 2768#ifdef CONFIG_IDE_PROC_FS 2769 .proc = idetape_proc, 2770#endif 2771}; 2772 2773/* Our character device supporting functions, passed to register_chrdev. */ 2774static const struct file_operations idetape_fops = { 2775 .owner = THIS_MODULE, 2776 .read = idetape_chrdev_read, 2777 .write = idetape_chrdev_write, 2778 .ioctl = idetape_chrdev_ioctl, 2779 .open = idetape_chrdev_open, 2780 .release = idetape_chrdev_release, 2781}; 2782 2783static int idetape_open(struct inode *inode, struct file *filp) 2784{ 2785 struct gendisk *disk = inode->i_bdev->bd_disk; 2786 struct ide_tape_obj *tape; 2787 2788 tape = ide_tape_get(disk); 2789 if (!tape) 2790 return -ENXIO; 2791 2792 return 0; 2793} 2794 2795static int idetape_release(struct inode *inode, struct file *filp) 2796{ 2797 struct gendisk *disk = inode->i_bdev->bd_disk; 2798 struct ide_tape_obj *tape = ide_tape_g(disk); 2799 2800 ide_tape_put(tape); 2801 2802 return 0; 2803} 2804 2805static int idetape_ioctl(struct inode *inode, struct file *file, 2806 unsigned int cmd, unsigned long arg) 2807{ 2808 struct block_device *bdev = inode->i_bdev; 2809 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 2810 ide_drive_t *drive = tape->drive; 2811 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 2812 if (err == -EINVAL) 2813 err = idetape_blkdev_ioctl(drive, cmd, arg); 2814 return err; 2815} 2816 2817static struct block_device_operations idetape_block_ops = { 2818 .owner = THIS_MODULE, 2819 .open = idetape_open, 2820 .release = idetape_release, 2821 .ioctl = idetape_ioctl, 2822}; 2823 2824static int ide_tape_probe(ide_drive_t *drive) 2825{ 2826 idetape_tape_t *tape; 2827 struct gendisk *g; 2828 int minor; 2829 2830 if (!strstr("ide-tape", drive->driver_req)) 2831 goto failed; 2832 if (!drive->present) 2833 goto failed; 2834 if (drive->media != ide_tape) 2835 goto failed; 2836 if (!idetape_identify_device(drive)) { 2837 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2838 " the driver\n", drive->name); 2839 goto failed; 2840 } 2841 if (drive->scsi) { 2842 printk(KERN_INFO "ide-tape: passing drive %s to ide-scsi" 2843 " emulation.\n", drive->name); 2844 goto failed; 2845 } 2846 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2847 if (tape == NULL) { 2848 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2849 drive->name); 2850 goto failed; 2851 } 2852 2853 g = alloc_disk(1 << PARTN_BITS); 2854 if (!g) 2855 goto out_free_tape; 2856 2857 ide_init_disk(g, drive); 2858 2859 ide_proc_register_driver(drive, &idetape_driver); 2860 2861 kref_init(&tape->kref); 2862 2863 tape->drive = drive; 2864 tape->driver = &idetape_driver; 2865 tape->disk = g; 2866 2867 g->private_data = &tape->driver; 2868 2869 drive->driver_data = tape; 2870 2871 mutex_lock(&idetape_ref_mutex); 2872 for (minor = 0; idetape_devs[minor]; minor++) 2873 ; 2874 idetape_devs[minor] = tape; 2875 mutex_unlock(&idetape_ref_mutex); 2876 2877 idetape_setup(drive, tape, minor); 2878 2879 device_create(idetape_sysfs_class, &drive->gendev, 2880 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name); 2881 device_create(idetape_sysfs_class, &drive->gendev, 2882 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name); 2883 2884 g->fops = &idetape_block_ops; 2885 ide_register_region(g); 2886 2887 return 0; 2888 2889out_free_tape: 2890 kfree(tape); 2891failed: 2892 return -ENODEV; 2893} 2894 2895static void __exit idetape_exit(void) 2896{ 2897 driver_unregister(&idetape_driver.gen_driver); 2898 class_destroy(idetape_sysfs_class); 2899 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2900} 2901 2902static int __init idetape_init(void) 2903{ 2904 int error = 1; 2905 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2906 if (IS_ERR(idetape_sysfs_class)) { 2907 idetape_sysfs_class = NULL; 2908 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2909 error = -EBUSY; 2910 goto out; 2911 } 2912 2913 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2914 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2915 " interface\n"); 2916 error = -EBUSY; 2917 goto out_free_class; 2918 } 2919 2920 error = driver_register(&idetape_driver.gen_driver); 2921 if (error) 2922 goto out_free_driver; 2923 2924 return 0; 2925 2926out_free_driver: 2927 driver_unregister(&idetape_driver.gen_driver); 2928out_free_class: 2929 class_destroy(idetape_sysfs_class); 2930out: 2931 return error; 2932} 2933 2934MODULE_ALIAS("ide:*m-tape*"); 2935module_init(idetape_init); 2936module_exit(idetape_exit); 2937MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2938MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2939MODULE_LICENSE("GPL"); 2940