ide-tape.c revision 4b5075050072ed7c4730ee547ae80117c4fa8513
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->tp_ops->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->tp_ops->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(ide_drive_t *drive, 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(drive, 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} 589 590static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 591{ 592 struct request *rq = HWGROUP(drive)->rq; 593 idetape_tape_t *tape = drive->driver_data; 594 unsigned long flags; 595 int error; 596 597 debug_log(DBG_PROCS, "Enter %s\n", __func__); 598 599 switch (uptodate) { 600 case 0: error = IDETAPE_ERROR_GENERAL; break; 601 case 1: error = 0; break; 602 default: error = uptodate; 603 } 604 rq->errors = error; 605 if (error) 606 tape->failed_pc = NULL; 607 608 if (!blk_special_request(rq)) { 609 ide_end_request(drive, uptodate, nr_sects); 610 return 0; 611 } 612 613 spin_lock_irqsave(&tape->lock, flags); 614 615 ide_end_drive_cmd(drive, 0, 0); 616 617 spin_unlock_irqrestore(&tape->lock, flags); 618 return 0; 619} 620 621static void ide_tape_callback(ide_drive_t *drive) 622{ 623 idetape_tape_t *tape = drive->driver_data; 624 struct ide_atapi_pc *pc = tape->pc; 625 int uptodate = pc->error ? 0 : 1; 626 627 debug_log(DBG_PROCS, "Enter %s\n", __func__); 628 629 if (tape->failed_pc == pc) 630 tape->failed_pc = NULL; 631 632 if (pc->c[0] == REQUEST_SENSE) { 633 if (uptodate) 634 idetape_analyze_error(drive, pc->buf); 635 else 636 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE " 637 "itself - Aborting request!\n"); 638 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 639 struct request *rq = drive->hwif->hwgroup->rq; 640 int blocks = pc->xferred / tape->blk_size; 641 642 tape->avg_size += blocks * tape->blk_size; 643 644 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 645 tape->avg_speed = tape->avg_size * HZ / 646 (jiffies - tape->avg_time) / 1024; 647 tape->avg_size = 0; 648 tape->avg_time = jiffies; 649 } 650 651 tape->first_frame += blocks; 652 rq->current_nr_sectors -= blocks; 653 654 if (pc->error) 655 uptodate = pc->error; 656 } else if (pc->c[0] == READ_POSITION && uptodate) { 657 u8 *readpos = tape->pc->buf; 658 659 debug_log(DBG_SENSE, "BOP - %s\n", 660 (readpos[0] & 0x80) ? "Yes" : "No"); 661 debug_log(DBG_SENSE, "EOP - %s\n", 662 (readpos[0] & 0x40) ? "Yes" : "No"); 663 664 if (readpos[0] & 0x4) { 665 printk(KERN_INFO "ide-tape: Block location is unknown" 666 "to the tape\n"); 667 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags); 668 uptodate = 0; 669 } else { 670 debug_log(DBG_SENSE, "Block Location - %u\n", 671 be32_to_cpu(*(u32 *)&readpos[4])); 672 673 tape->partition = readpos[1]; 674 tape->first_frame = be32_to_cpu(*(u32 *)&readpos[4]); 675 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags); 676 } 677 } 678 679 idetape_end_request(drive, uptodate, 0); 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->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 770static void ide_tape_handle_dsc(ide_drive_t *drive) 771{ 772 idetape_tape_t *tape = drive->driver_data; 773 774 /* Media access command */ 775 tape->dsc_polling_start = jiffies; 776 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 777 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 778 /* Allow ide.c to handle other requests */ 779 idetape_postpone_request(drive); 780} 781 782static void ide_tape_io_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 783 unsigned int bcount, int write) 784{ 785 if (write) 786 idetape_output_buffers(drive, pc, bcount); 787 else 788 idetape_input_buffers(drive, pc, bcount); 789} 790 791/* 792 * This is the usual interrupt handler which will be called during a packet 793 * command. We will transfer some of the data (as requested by the drive) and 794 * will re-point interrupt handler to us. When data transfer is finished, we 795 * will act according to the algorithm described before 796 * idetape_issue_pc. 797 */ 798static ide_startstop_t idetape_pc_intr(ide_drive_t *drive) 799{ 800 idetape_tape_t *tape = drive->driver_data; 801 802 return ide_pc_intr(drive, tape->pc, idetape_pc_intr, IDETAPE_WAIT_CMD, 803 NULL, idetape_update_buffers, idetape_retry_pc, 804 ide_tape_handle_dsc, ide_tape_io_buffers); 805} 806 807/* 808 * Packet Command Interface 809 * 810 * The current Packet Command is available in tape->pc, and will not change 811 * until we finish handling it. Each packet command is associated with a 812 * callback function that will be called when the command is finished. 813 * 814 * The handling will be done in three stages: 815 * 816 * 1. idetape_issue_pc will send the packet command to the drive, and will set 817 * the interrupt handler to idetape_pc_intr. 818 * 819 * 2. On each interrupt, idetape_pc_intr will be called. This step will be 820 * repeated until the device signals us that no more interrupts will be issued. 821 * 822 * 3. ATAPI Tape media access commands have immediate status with a delayed 823 * process. In case of a successful initiation of a media access packet command, 824 * the DSC bit will be set when the actual execution of the command is finished. 825 * Since the tape drive will not issue an interrupt, we have to poll for this 826 * event. In this case, we define the request as "low priority request" by 827 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 828 * exit the driver. 829 * 830 * ide.c will then give higher priority to requests which originate from the 831 * other device, until will change rq_status to RQ_ACTIVE. 832 * 833 * 4. When the packet command is finished, it will be checked for errors. 834 * 835 * 5. In case an error was found, we queue a request sense packet command in 836 * front of the request queue and retry the operation up to 837 * IDETAPE_MAX_PC_RETRIES times. 838 * 839 * 6. In case no error was found, or we decided to give up and not to retry 840 * again, the callback function will be called and then we will handle the next 841 * request. 842 */ 843static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 844{ 845 idetape_tape_t *tape = drive->driver_data; 846 847 return ide_transfer_pc(drive, tape->pc, idetape_pc_intr, 848 IDETAPE_WAIT_CMD, NULL); 849} 850 851static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 852 struct ide_atapi_pc *pc) 853{ 854 idetape_tape_t *tape = drive->driver_data; 855 856 if (tape->pc->c[0] == REQUEST_SENSE && 857 pc->c[0] == REQUEST_SENSE) { 858 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 859 "Two request sense in serial were issued\n"); 860 } 861 862 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 863 tape->failed_pc = pc; 864 /* Set the current packet command */ 865 tape->pc = pc; 866 867 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 868 (pc->flags & PC_FLAG_ABORT)) { 869 /* 870 * We will "abort" retrying a packet command in case legitimate 871 * error code was received (crossing a filemark, or end of the 872 * media, for example). 873 */ 874 if (!(pc->flags & PC_FLAG_ABORT)) { 875 if (!(pc->c[0] == TEST_UNIT_READY && 876 tape->sense_key == 2 && tape->asc == 4 && 877 (tape->ascq == 1 || tape->ascq == 8))) { 878 printk(KERN_ERR "ide-tape: %s: I/O error, " 879 "pc = %2x, key = %2x, " 880 "asc = %2x, ascq = %2x\n", 881 tape->name, pc->c[0], 882 tape->sense_key, tape->asc, 883 tape->ascq); 884 } 885 /* Giving up */ 886 pc->error = IDETAPE_ERROR_GENERAL; 887 } 888 tape->failed_pc = NULL; 889 pc->callback(drive); 890 return ide_stopped; 891 } 892 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 893 894 pc->retries++; 895 896 return ide_issue_pc(drive, pc, idetape_transfer_pc, 897 IDETAPE_WAIT_CMD, NULL); 898} 899 900/* A mode sense command is used to "sense" tape parameters. */ 901static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 902{ 903 idetape_init_pc(pc); 904 pc->c[0] = MODE_SENSE; 905 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 906 /* DBD = 1 - Don't return block descriptors */ 907 pc->c[1] = 8; 908 pc->c[2] = page_code; 909 /* 910 * Changed pc->c[3] to 0 (255 will at best return unused info). 911 * 912 * For SCSI this byte is defined as subpage instead of high byte 913 * of length and some IDE drives seem to interpret it this way 914 * and return an error when 255 is used. 915 */ 916 pc->c[3] = 0; 917 /* We will just discard data in that case */ 918 pc->c[4] = 255; 919 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 920 pc->req_xfer = 12; 921 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 922 pc->req_xfer = 24; 923 else 924 pc->req_xfer = 50; 925} 926 927static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 928{ 929 ide_hwif_t *hwif = drive->hwif; 930 idetape_tape_t *tape = drive->driver_data; 931 struct ide_atapi_pc *pc = tape->pc; 932 u8 stat; 933 934 stat = hwif->tp_ops->read_status(hwif); 935 936 if (stat & SEEK_STAT) { 937 if (stat & ERR_STAT) { 938 /* Error detected */ 939 if (pc->c[0] != TEST_UNIT_READY) 940 printk(KERN_ERR "ide-tape: %s: I/O error, ", 941 tape->name); 942 /* Retry operation */ 943 idetape_retry_pc(drive); 944 return ide_stopped; 945 } 946 pc->error = 0; 947 } else { 948 pc->error = IDETAPE_ERROR_GENERAL; 949 tape->failed_pc = NULL; 950 } 951 pc->callback(drive); 952 return ide_stopped; 953} 954 955static void ide_tape_create_rw_cmd(idetape_tape_t *tape, 956 struct ide_atapi_pc *pc, unsigned int length, 957 struct idetape_bh *bh, u8 opcode) 958{ 959 idetape_init_pc(pc); 960 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 961 pc->c[1] = 1; 962 pc->bh = bh; 963 pc->buf = NULL; 964 pc->buf_size = length * tape->blk_size; 965 pc->req_xfer = pc->buf_size; 966 if (pc->req_xfer == tape->buffer_size) 967 pc->flags |= PC_FLAG_DMA_OK; 968 969 if (opcode == READ_6) { 970 pc->c[0] = READ_6; 971 atomic_set(&bh->b_count, 0); 972 } else if (opcode == WRITE_6) { 973 pc->c[0] = WRITE_6; 974 pc->flags |= PC_FLAG_WRITING; 975 pc->b_data = bh->b_data; 976 pc->b_count = atomic_read(&bh->b_count); 977 } 978} 979 980static ide_startstop_t idetape_do_request(ide_drive_t *drive, 981 struct request *rq, sector_t block) 982{ 983 ide_hwif_t *hwif = drive->hwif; 984 idetape_tape_t *tape = drive->driver_data; 985 struct ide_atapi_pc *pc = NULL; 986 struct request *postponed_rq = tape->postponed_rq; 987 u8 stat; 988 989 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld," 990 " current_nr_sectors: %d\n", 991 rq->sector, rq->nr_sectors, rq->current_nr_sectors); 992 993 if (!blk_special_request(rq)) { 994 /* We do not support buffer cache originated requests. */ 995 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 996 "request queue (%d)\n", drive->name, rq->cmd_type); 997 ide_end_request(drive, 0, 0); 998 return ide_stopped; 999 } 1000 1001 /* Retry a failed packet command */ 1002 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) { 1003 pc = tape->failed_pc; 1004 goto out; 1005 } 1006 1007 if (postponed_rq != NULL) 1008 if (rq != postponed_rq) { 1009 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 1010 "Two DSC requests were queued\n"); 1011 idetape_end_request(drive, 0, 0); 1012 return ide_stopped; 1013 } 1014 1015 tape->postponed_rq = NULL; 1016 1017 /* 1018 * If the tape is still busy, postpone our request and service 1019 * the other device meanwhile. 1020 */ 1021 stat = hwif->tp_ops->read_status(hwif); 1022 1023 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2)) 1024 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1025 1026 if (drive->post_reset == 1) { 1027 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1028 drive->post_reset = 0; 1029 } 1030 1031 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) && 1032 (stat & SEEK_STAT) == 0) { 1033 if (postponed_rq == NULL) { 1034 tape->dsc_polling_start = jiffies; 1035 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 1036 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 1037 } else if (time_after(jiffies, tape->dsc_timeout)) { 1038 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 1039 tape->name); 1040 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1041 idetape_media_access_finished(drive); 1042 return ide_stopped; 1043 } else { 1044 return ide_do_reset(drive); 1045 } 1046 } else if (time_after(jiffies, 1047 tape->dsc_polling_start + 1048 IDETAPE_DSC_MA_THRESHOLD)) 1049 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 1050 idetape_postpone_request(drive); 1051 return ide_stopped; 1052 } 1053 if (rq->cmd[0] & REQ_IDETAPE_READ) { 1054 pc = idetape_next_pc_storage(drive); 1055 ide_tape_create_rw_cmd(tape, pc, rq->current_nr_sectors, 1056 (struct idetape_bh *)rq->special, 1057 READ_6); 1058 goto out; 1059 } 1060 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 1061 pc = idetape_next_pc_storage(drive); 1062 ide_tape_create_rw_cmd(tape, pc, rq->current_nr_sectors, 1063 (struct idetape_bh *)rq->special, 1064 WRITE_6); 1065 goto out; 1066 } 1067 if (rq->cmd[0] & REQ_IDETAPE_PC1) { 1068 pc = (struct ide_atapi_pc *) rq->buffer; 1069 rq->cmd[0] &= ~(REQ_IDETAPE_PC1); 1070 rq->cmd[0] |= REQ_IDETAPE_PC2; 1071 goto out; 1072 } 1073 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1074 idetape_media_access_finished(drive); 1075 return ide_stopped; 1076 } 1077 BUG(); 1078out: 1079 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags)) 1080 pc->flags |= PC_FLAG_DRQ_INTERRUPT; 1081 1082 return idetape_issue_pc(drive, pc); 1083} 1084 1085/* 1086 * The function below uses __get_free_pages to allocate a data buffer of size 1087 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 1088 * much as possible. 1089 * 1090 * It returns a pointer to the newly allocated buffer, or NULL in case of 1091 * failure. 1092 */ 1093static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 1094 int full, int clear) 1095{ 1096 struct idetape_bh *prev_bh, *bh, *merge_bh; 1097 int pages = tape->pages_per_buffer; 1098 unsigned int order, b_allocd; 1099 char *b_data = NULL; 1100 1101 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1102 bh = merge_bh; 1103 if (bh == NULL) 1104 goto abort; 1105 1106 order = fls(pages) - 1; 1107 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1108 if (!bh->b_data) 1109 goto abort; 1110 b_allocd = (1 << order) * PAGE_SIZE; 1111 pages &= (order-1); 1112 1113 if (clear) 1114 memset(bh->b_data, 0, b_allocd); 1115 bh->b_reqnext = NULL; 1116 bh->b_size = b_allocd; 1117 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1118 1119 while (pages) { 1120 order = fls(pages) - 1; 1121 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1122 if (!b_data) 1123 goto abort; 1124 b_allocd = (1 << order) * PAGE_SIZE; 1125 1126 if (clear) 1127 memset(b_data, 0, b_allocd); 1128 1129 /* newly allocated page frames below buffer header or ...*/ 1130 if (bh->b_data == b_data + b_allocd) { 1131 bh->b_size += b_allocd; 1132 bh->b_data -= b_allocd; 1133 if (full) 1134 atomic_add(b_allocd, &bh->b_count); 1135 continue; 1136 } 1137 /* they are above the header */ 1138 if (b_data == bh->b_data + bh->b_size) { 1139 bh->b_size += b_allocd; 1140 if (full) 1141 atomic_add(b_allocd, &bh->b_count); 1142 continue; 1143 } 1144 prev_bh = bh; 1145 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1146 if (!bh) { 1147 free_pages((unsigned long) b_data, order); 1148 goto abort; 1149 } 1150 bh->b_reqnext = NULL; 1151 bh->b_data = b_data; 1152 bh->b_size = b_allocd; 1153 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1154 prev_bh->b_reqnext = bh; 1155 1156 pages &= (order-1); 1157 } 1158 1159 bh->b_size -= tape->excess_bh_size; 1160 if (full) 1161 atomic_sub(tape->excess_bh_size, &bh->b_count); 1162 return merge_bh; 1163abort: 1164 ide_tape_kfree_buffer(tape); 1165 return NULL; 1166} 1167 1168static int idetape_copy_stage_from_user(idetape_tape_t *tape, 1169 const char __user *buf, int n) 1170{ 1171 struct idetape_bh *bh = tape->bh; 1172 int count; 1173 int ret = 0; 1174 1175 while (n) { 1176 if (bh == NULL) { 1177 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1178 __func__); 1179 return 1; 1180 } 1181 count = min((unsigned int) 1182 (bh->b_size - atomic_read(&bh->b_count)), 1183 (unsigned int)n); 1184 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 1185 count)) 1186 ret = 1; 1187 n -= count; 1188 atomic_add(count, &bh->b_count); 1189 buf += count; 1190 if (atomic_read(&bh->b_count) == bh->b_size) { 1191 bh = bh->b_reqnext; 1192 if (bh) 1193 atomic_set(&bh->b_count, 0); 1194 } 1195 } 1196 tape->bh = bh; 1197 return ret; 1198} 1199 1200static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1201 int n) 1202{ 1203 struct idetape_bh *bh = tape->bh; 1204 int count; 1205 int ret = 0; 1206 1207 while (n) { 1208 if (bh == NULL) { 1209 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1210 __func__); 1211 return 1; 1212 } 1213 count = min(tape->b_count, n); 1214 if (copy_to_user(buf, tape->b_data, count)) 1215 ret = 1; 1216 n -= count; 1217 tape->b_data += count; 1218 tape->b_count -= count; 1219 buf += count; 1220 if (!tape->b_count) { 1221 bh = bh->b_reqnext; 1222 tape->bh = bh; 1223 if (bh) { 1224 tape->b_data = bh->b_data; 1225 tape->b_count = atomic_read(&bh->b_count); 1226 } 1227 } 1228 } 1229 return ret; 1230} 1231 1232static void idetape_init_merge_buffer(idetape_tape_t *tape) 1233{ 1234 struct idetape_bh *bh = tape->merge_bh; 1235 tape->bh = tape->merge_bh; 1236 1237 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1238 atomic_set(&bh->b_count, 0); 1239 else { 1240 tape->b_data = bh->b_data; 1241 tape->b_count = atomic_read(&bh->b_count); 1242 } 1243} 1244 1245/* 1246 * Write a filemark if write_filemark=1. Flush the device buffers without 1247 * writing a filemark otherwise. 1248 */ 1249static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1250 struct ide_atapi_pc *pc, int write_filemark) 1251{ 1252 idetape_init_pc(pc); 1253 pc->c[0] = WRITE_FILEMARKS; 1254 pc->c[4] = write_filemark; 1255 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1256} 1257 1258static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc) 1259{ 1260 idetape_init_pc(pc); 1261 pc->c[0] = TEST_UNIT_READY; 1262} 1263 1264/* 1265 * We add a special packet command request to the tail of the request queue, and 1266 * wait for it to be serviced. This is not to be called from within the request 1267 * handling part of the driver! We allocate here data on the stack and it is 1268 * valid until the request is finished. This is not the case for the bottom part 1269 * of the driver, where we are always leaving the functions to wait for an 1270 * interrupt or a timer event. 1271 * 1272 * From the bottom part of the driver, we should allocate safe memory using 1273 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request 1274 * to the request list without waiting for it to be serviced! In that case, we 1275 * usually use idetape_queue_pc_head(). 1276 */ 1277static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc) 1278{ 1279 struct ide_tape_obj *tape = drive->driver_data; 1280 struct request *rq; 1281 int error; 1282 1283 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1284 rq->cmd_type = REQ_TYPE_SPECIAL; 1285 rq->cmd[0] = REQ_IDETAPE_PC1; 1286 rq->buffer = (char *)pc; 1287 error = blk_execute_rq(drive->queue, tape->disk, rq, 0); 1288 blk_put_request(rq); 1289 return error; 1290} 1291 1292static void idetape_create_load_unload_cmd(ide_drive_t *drive, 1293 struct ide_atapi_pc *pc, int cmd) 1294{ 1295 idetape_init_pc(pc); 1296 pc->c[0] = START_STOP; 1297 pc->c[4] = cmd; 1298 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1299} 1300 1301static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1302{ 1303 idetape_tape_t *tape = drive->driver_data; 1304 struct ide_atapi_pc pc; 1305 int load_attempted = 0; 1306 1307 /* Wait for the tape to become ready */ 1308 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 1309 timeout += jiffies; 1310 while (time_before(jiffies, timeout)) { 1311 idetape_create_test_unit_ready_cmd(&pc); 1312 if (!idetape_queue_pc_tail(drive, &pc)) 1313 return 0; 1314 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1315 || (tape->asc == 0x3A)) { 1316 /* no media */ 1317 if (load_attempted) 1318 return -ENOMEDIUM; 1319 idetape_create_load_unload_cmd(drive, &pc, 1320 IDETAPE_LU_LOAD_MASK); 1321 idetape_queue_pc_tail(drive, &pc); 1322 load_attempted = 1; 1323 /* not about to be ready */ 1324 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1325 (tape->ascq == 1 || tape->ascq == 8))) 1326 return -EIO; 1327 msleep(100); 1328 } 1329 return -EIO; 1330} 1331 1332static int idetape_flush_tape_buffers(ide_drive_t *drive) 1333{ 1334 struct ide_atapi_pc pc; 1335 int rc; 1336 1337 idetape_create_write_filemark_cmd(drive, &pc, 0); 1338 rc = idetape_queue_pc_tail(drive, &pc); 1339 if (rc) 1340 return rc; 1341 idetape_wait_ready(drive, 60 * 5 * HZ); 1342 return 0; 1343} 1344 1345static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1346{ 1347 idetape_init_pc(pc); 1348 pc->c[0] = READ_POSITION; 1349 pc->req_xfer = 20; 1350} 1351 1352static int idetape_read_position(ide_drive_t *drive) 1353{ 1354 idetape_tape_t *tape = drive->driver_data; 1355 struct ide_atapi_pc pc; 1356 int position; 1357 1358 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1359 1360 idetape_create_read_position_cmd(&pc); 1361 if (idetape_queue_pc_tail(drive, &pc)) 1362 return -1; 1363 position = tape->first_frame; 1364 return position; 1365} 1366 1367static void idetape_create_locate_cmd(ide_drive_t *drive, 1368 struct ide_atapi_pc *pc, 1369 unsigned int block, u8 partition, int skip) 1370{ 1371 idetape_init_pc(pc); 1372 pc->c[0] = POSITION_TO_ELEMENT; 1373 pc->c[1] = 2; 1374 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1375 pc->c[8] = partition; 1376 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1377} 1378 1379static int idetape_create_prevent_cmd(ide_drive_t *drive, 1380 struct ide_atapi_pc *pc, int prevent) 1381{ 1382 idetape_tape_t *tape = drive->driver_data; 1383 1384 /* device supports locking according to capabilities page */ 1385 if (!(tape->caps[6] & 0x01)) 1386 return 0; 1387 1388 idetape_init_pc(pc); 1389 pc->c[0] = ALLOW_MEDIUM_REMOVAL; 1390 pc->c[4] = prevent; 1391 return 1; 1392} 1393 1394static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1395{ 1396 idetape_tape_t *tape = drive->driver_data; 1397 1398 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1399 return; 1400 1401 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags); 1402 tape->merge_bh_size = 0; 1403 if (tape->merge_bh != NULL) { 1404 ide_tape_kfree_buffer(tape); 1405 tape->merge_bh = NULL; 1406 } 1407 1408 tape->chrdev_dir = IDETAPE_DIR_NONE; 1409} 1410 1411/* 1412 * Position the tape to the requested block using the LOCATE packet command. 1413 * A READ POSITION command is then issued to check where we are positioned. Like 1414 * all higher level operations, we queue the commands at the tail of the request 1415 * queue and wait for their completion. 1416 */ 1417static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1418 u8 partition, int skip) 1419{ 1420 idetape_tape_t *tape = drive->driver_data; 1421 int retval; 1422 struct ide_atapi_pc pc; 1423 1424 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1425 __ide_tape_discard_merge_buffer(drive); 1426 idetape_wait_ready(drive, 60 * 5 * HZ); 1427 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1428 retval = idetape_queue_pc_tail(drive, &pc); 1429 if (retval) 1430 return (retval); 1431 1432 idetape_create_read_position_cmd(&pc); 1433 return (idetape_queue_pc_tail(drive, &pc)); 1434} 1435 1436static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1437 int restore_position) 1438{ 1439 idetape_tape_t *tape = drive->driver_data; 1440 int seek, position; 1441 1442 __ide_tape_discard_merge_buffer(drive); 1443 if (restore_position) { 1444 position = idetape_read_position(drive); 1445 seek = position > 0 ? position : 0; 1446 if (idetape_position_tape(drive, seek, 0, 0)) { 1447 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1448 " %s\n", tape->name, __func__); 1449 return; 1450 } 1451 } 1452} 1453 1454/* 1455 * Generate a read/write request for the block device interface and wait for it 1456 * to be serviced. 1457 */ 1458static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1459 struct idetape_bh *bh) 1460{ 1461 idetape_tape_t *tape = drive->driver_data; 1462 struct request *rq; 1463 int ret, errors; 1464 1465 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1466 1467 rq = blk_get_request(drive->queue, READ, __GFP_WAIT); 1468 rq->cmd_type = REQ_TYPE_SPECIAL; 1469 rq->cmd[0] = cmd; 1470 rq->rq_disk = tape->disk; 1471 rq->special = (void *)bh; 1472 rq->sector = tape->first_frame; 1473 rq->nr_sectors = blocks; 1474 rq->current_nr_sectors = blocks; 1475 blk_execute_rq(drive->queue, tape->disk, rq, 0); 1476 1477 errors = rq->errors; 1478 ret = tape->blk_size * (blocks - rq->current_nr_sectors); 1479 blk_put_request(rq); 1480 1481 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1482 return 0; 1483 1484 if (tape->merge_bh) 1485 idetape_init_merge_buffer(tape); 1486 if (errors == IDETAPE_ERROR_GENERAL) 1487 return -EIO; 1488 return ret; 1489} 1490 1491static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1492{ 1493 idetape_init_pc(pc); 1494 pc->c[0] = INQUIRY; 1495 pc->c[4] = 254; 1496 pc->req_xfer = 254; 1497} 1498 1499static void idetape_create_rewind_cmd(ide_drive_t *drive, 1500 struct ide_atapi_pc *pc) 1501{ 1502 idetape_init_pc(pc); 1503 pc->c[0] = REZERO_UNIT; 1504 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1505} 1506 1507static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1508{ 1509 idetape_init_pc(pc); 1510 pc->c[0] = ERASE; 1511 pc->c[1] = 1; 1512 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1513} 1514 1515static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1516{ 1517 idetape_init_pc(pc); 1518 pc->c[0] = SPACE; 1519 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1520 pc->c[1] = cmd; 1521 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1522} 1523 1524/* Queue up a character device originated write request. */ 1525static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1526{ 1527 idetape_tape_t *tape = drive->driver_data; 1528 1529 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1530 1531 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1532 blocks, tape->merge_bh); 1533} 1534 1535static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1536{ 1537 idetape_tape_t *tape = drive->driver_data; 1538 int blocks, min; 1539 struct idetape_bh *bh; 1540 1541 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1542 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1543 " but we are not writing.\n"); 1544 return; 1545 } 1546 if (tape->merge_bh_size > tape->buffer_size) { 1547 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1548 tape->merge_bh_size = tape->buffer_size; 1549 } 1550 if (tape->merge_bh_size) { 1551 blocks = tape->merge_bh_size / tape->blk_size; 1552 if (tape->merge_bh_size % tape->blk_size) { 1553 unsigned int i; 1554 1555 blocks++; 1556 i = tape->blk_size - tape->merge_bh_size % 1557 tape->blk_size; 1558 bh = tape->bh->b_reqnext; 1559 while (bh) { 1560 atomic_set(&bh->b_count, 0); 1561 bh = bh->b_reqnext; 1562 } 1563 bh = tape->bh; 1564 while (i) { 1565 if (bh == NULL) { 1566 printk(KERN_INFO "ide-tape: bug," 1567 " bh NULL\n"); 1568 break; 1569 } 1570 min = min(i, (unsigned int)(bh->b_size - 1571 atomic_read(&bh->b_count))); 1572 memset(bh->b_data + atomic_read(&bh->b_count), 1573 0, min); 1574 atomic_add(min, &bh->b_count); 1575 i -= min; 1576 bh = bh->b_reqnext; 1577 } 1578 } 1579 (void) idetape_add_chrdev_write_request(drive, blocks); 1580 tape->merge_bh_size = 0; 1581 } 1582 if (tape->merge_bh != NULL) { 1583 ide_tape_kfree_buffer(tape); 1584 tape->merge_bh = NULL; 1585 } 1586 tape->chrdev_dir = IDETAPE_DIR_NONE; 1587} 1588 1589static int idetape_init_read(ide_drive_t *drive) 1590{ 1591 idetape_tape_t *tape = drive->driver_data; 1592 int bytes_read; 1593 1594 /* Initialize read operation */ 1595 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1596 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1597 ide_tape_flush_merge_buffer(drive); 1598 idetape_flush_tape_buffers(drive); 1599 } 1600 if (tape->merge_bh || tape->merge_bh_size) { 1601 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1602 " 0 now\n"); 1603 tape->merge_bh_size = 0; 1604 } 1605 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1606 if (!tape->merge_bh) 1607 return -ENOMEM; 1608 tape->chrdev_dir = IDETAPE_DIR_READ; 1609 1610 /* 1611 * Issue a read 0 command to ensure that DSC handshake is 1612 * switched from completion mode to buffer available mode. 1613 * No point in issuing this if DSC overlap isn't supported, some 1614 * drives (Seagate STT3401A) will return an error. 1615 */ 1616 if (drive->dsc_overlap) { 1617 bytes_read = idetape_queue_rw_tail(drive, 1618 REQ_IDETAPE_READ, 0, 1619 tape->merge_bh); 1620 if (bytes_read < 0) { 1621 ide_tape_kfree_buffer(tape); 1622 tape->merge_bh = NULL; 1623 tape->chrdev_dir = IDETAPE_DIR_NONE; 1624 return bytes_read; 1625 } 1626 } 1627 } 1628 1629 return 0; 1630} 1631 1632/* called from idetape_chrdev_read() to service a chrdev read request. */ 1633static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1634{ 1635 idetape_tape_t *tape = drive->driver_data; 1636 1637 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1638 1639 /* If we are at a filemark, return a read length of 0 */ 1640 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1641 return 0; 1642 1643 idetape_init_read(drive); 1644 1645 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1646 tape->merge_bh); 1647} 1648 1649static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1650{ 1651 idetape_tape_t *tape = drive->driver_data; 1652 struct idetape_bh *bh; 1653 int blocks; 1654 1655 while (bcount) { 1656 unsigned int count; 1657 1658 bh = tape->merge_bh; 1659 count = min(tape->buffer_size, bcount); 1660 bcount -= count; 1661 blocks = count / tape->blk_size; 1662 while (count) { 1663 atomic_set(&bh->b_count, 1664 min(count, (unsigned int)bh->b_size)); 1665 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1666 count -= atomic_read(&bh->b_count); 1667 bh = bh->b_reqnext; 1668 } 1669 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1670 tape->merge_bh); 1671 } 1672} 1673 1674/* 1675 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1676 * currently support only one partition. 1677 */ 1678static int idetape_rewind_tape(ide_drive_t *drive) 1679{ 1680 int retval; 1681 struct ide_atapi_pc pc; 1682 idetape_tape_t *tape; 1683 tape = drive->driver_data; 1684 1685 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1686 1687 idetape_create_rewind_cmd(drive, &pc); 1688 retval = idetape_queue_pc_tail(drive, &pc); 1689 if (retval) 1690 return retval; 1691 1692 idetape_create_read_position_cmd(&pc); 1693 retval = idetape_queue_pc_tail(drive, &pc); 1694 if (retval) 1695 return retval; 1696 return 0; 1697} 1698 1699/* mtio.h compatible commands should be issued to the chrdev interface. */ 1700static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1701 unsigned long arg) 1702{ 1703 idetape_tape_t *tape = drive->driver_data; 1704 void __user *argp = (void __user *)arg; 1705 1706 struct idetape_config { 1707 int dsc_rw_frequency; 1708 int dsc_media_access_frequency; 1709 int nr_stages; 1710 } config; 1711 1712 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1713 1714 switch (cmd) { 1715 case 0x0340: 1716 if (copy_from_user(&config, argp, sizeof(config))) 1717 return -EFAULT; 1718 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1719 break; 1720 case 0x0350: 1721 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1722 config.nr_stages = 1; 1723 if (copy_to_user(argp, &config, sizeof(config))) 1724 return -EFAULT; 1725 break; 1726 default: 1727 return -EIO; 1728 } 1729 return 0; 1730} 1731 1732static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1733 int mt_count) 1734{ 1735 idetape_tape_t *tape = drive->driver_data; 1736 struct ide_atapi_pc pc; 1737 int retval, count = 0; 1738 int sprev = !!(tape->caps[4] & 0x20); 1739 1740 if (mt_count == 0) 1741 return 0; 1742 if (MTBSF == mt_op || MTBSFM == mt_op) { 1743 if (!sprev) 1744 return -EIO; 1745 mt_count = -mt_count; 1746 } 1747 1748 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1749 tape->merge_bh_size = 0; 1750 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1751 ++count; 1752 ide_tape_discard_merge_buffer(drive, 0); 1753 } 1754 1755 switch (mt_op) { 1756 case MTFSF: 1757 case MTBSF: 1758 idetape_create_space_cmd(&pc, mt_count - count, 1759 IDETAPE_SPACE_OVER_FILEMARK); 1760 return idetape_queue_pc_tail(drive, &pc); 1761 case MTFSFM: 1762 case MTBSFM: 1763 if (!sprev) 1764 return -EIO; 1765 retval = idetape_space_over_filemarks(drive, MTFSF, 1766 mt_count - count); 1767 if (retval) 1768 return retval; 1769 count = (MTBSFM == mt_op ? 1 : -1); 1770 return idetape_space_over_filemarks(drive, MTFSF, count); 1771 default: 1772 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 1773 mt_op); 1774 return -EIO; 1775 } 1776} 1777 1778/* 1779 * Our character device read / write functions. 1780 * 1781 * The tape is optimized to maximize throughput when it is transferring an 1782 * integral number of the "continuous transfer limit", which is a parameter of 1783 * the specific tape (26kB on my particular tape, 32kB for Onstream). 1784 * 1785 * As of version 1.3 of the driver, the character device provides an abstract 1786 * continuous view of the media - any mix of block sizes (even 1 byte) on the 1787 * same backup/restore procedure is supported. The driver will internally 1788 * convert the requests to the recommended transfer unit, so that an unmatch 1789 * between the user's block size to the recommended size will only result in a 1790 * (slightly) increased driver overhead, but will no longer hit performance. 1791 * This is not applicable to Onstream. 1792 */ 1793static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 1794 size_t count, loff_t *ppos) 1795{ 1796 struct ide_tape_obj *tape = ide_tape_f(file); 1797 ide_drive_t *drive = tape->drive; 1798 ssize_t bytes_read, temp, actually_read = 0, rc; 1799 ssize_t ret = 0; 1800 u16 ctl = *(u16 *)&tape->caps[12]; 1801 1802 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1803 1804 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1805 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags)) 1806 if (count > tape->blk_size && 1807 (count % tape->blk_size) == 0) 1808 tape->user_bs_factor = count / tape->blk_size; 1809 } 1810 rc = idetape_init_read(drive); 1811 if (rc < 0) 1812 return rc; 1813 if (count == 0) 1814 return (0); 1815 if (tape->merge_bh_size) { 1816 actually_read = min((unsigned int)(tape->merge_bh_size), 1817 (unsigned int)count); 1818 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 1819 ret = -EFAULT; 1820 buf += actually_read; 1821 tape->merge_bh_size -= actually_read; 1822 count -= actually_read; 1823 } 1824 while (count >= tape->buffer_size) { 1825 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1826 if (bytes_read <= 0) 1827 goto finish; 1828 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 1829 ret = -EFAULT; 1830 buf += bytes_read; 1831 count -= bytes_read; 1832 actually_read += bytes_read; 1833 } 1834 if (count) { 1835 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 1836 if (bytes_read <= 0) 1837 goto finish; 1838 temp = min((unsigned long)count, (unsigned long)bytes_read); 1839 if (idetape_copy_stage_to_user(tape, buf, temp)) 1840 ret = -EFAULT; 1841 actually_read += temp; 1842 tape->merge_bh_size = bytes_read-temp; 1843 } 1844finish: 1845 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) { 1846 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 1847 1848 idetape_space_over_filemarks(drive, MTFSF, 1); 1849 return 0; 1850 } 1851 1852 return ret ? ret : actually_read; 1853} 1854 1855static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 1856 size_t count, loff_t *ppos) 1857{ 1858 struct ide_tape_obj *tape = ide_tape_f(file); 1859 ide_drive_t *drive = tape->drive; 1860 ssize_t actually_written = 0; 1861 ssize_t ret = 0; 1862 u16 ctl = *(u16 *)&tape->caps[12]; 1863 1864 /* The drive is write protected. */ 1865 if (tape->write_prot) 1866 return -EACCES; 1867 1868 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 1869 1870 /* Initialize write operation */ 1871 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1872 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1873 ide_tape_discard_merge_buffer(drive, 1); 1874 if (tape->merge_bh || tape->merge_bh_size) { 1875 printk(KERN_ERR "ide-tape: merge_bh_size " 1876 "should be 0 now\n"); 1877 tape->merge_bh_size = 0; 1878 } 1879 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1880 if (!tape->merge_bh) 1881 return -ENOMEM; 1882 tape->chrdev_dir = IDETAPE_DIR_WRITE; 1883 idetape_init_merge_buffer(tape); 1884 1885 /* 1886 * Issue a write 0 command to ensure that DSC handshake is 1887 * switched from completion mode to buffer available mode. No 1888 * point in issuing this if DSC overlap isn't supported, some 1889 * drives (Seagate STT3401A) will return an error. 1890 */ 1891 if (drive->dsc_overlap) { 1892 ssize_t retval = idetape_queue_rw_tail(drive, 1893 REQ_IDETAPE_WRITE, 0, 1894 tape->merge_bh); 1895 if (retval < 0) { 1896 ide_tape_kfree_buffer(tape); 1897 tape->merge_bh = NULL; 1898 tape->chrdev_dir = IDETAPE_DIR_NONE; 1899 return retval; 1900 } 1901 } 1902 } 1903 if (count == 0) 1904 return (0); 1905 if (tape->merge_bh_size) { 1906 if (tape->merge_bh_size >= tape->buffer_size) { 1907 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 1908 tape->merge_bh_size = 0; 1909 } 1910 actually_written = min((unsigned int) 1911 (tape->buffer_size - tape->merge_bh_size), 1912 (unsigned int)count); 1913 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 1914 ret = -EFAULT; 1915 buf += actually_written; 1916 tape->merge_bh_size += actually_written; 1917 count -= actually_written; 1918 1919 if (tape->merge_bh_size == tape->buffer_size) { 1920 ssize_t retval; 1921 tape->merge_bh_size = 0; 1922 retval = idetape_add_chrdev_write_request(drive, ctl); 1923 if (retval <= 0) 1924 return (retval); 1925 } 1926 } 1927 while (count >= tape->buffer_size) { 1928 ssize_t retval; 1929 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 1930 ret = -EFAULT; 1931 buf += tape->buffer_size; 1932 count -= tape->buffer_size; 1933 retval = idetape_add_chrdev_write_request(drive, ctl); 1934 actually_written += tape->buffer_size; 1935 if (retval <= 0) 1936 return (retval); 1937 } 1938 if (count) { 1939 actually_written += count; 1940 if (idetape_copy_stage_from_user(tape, buf, count)) 1941 ret = -EFAULT; 1942 tape->merge_bh_size += count; 1943 } 1944 return ret ? ret : actually_written; 1945} 1946 1947static int idetape_write_filemark(ide_drive_t *drive) 1948{ 1949 struct ide_atapi_pc pc; 1950 1951 /* Write a filemark */ 1952 idetape_create_write_filemark_cmd(drive, &pc, 1); 1953 if (idetape_queue_pc_tail(drive, &pc)) { 1954 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 1955 return -EIO; 1956 } 1957 return 0; 1958} 1959 1960/* 1961 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 1962 * requested. 1963 * 1964 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 1965 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 1966 * usually not supported. 1967 * 1968 * The following commands are currently not supported: 1969 * 1970 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 1971 * MT_ST_WRITE_THRESHOLD. 1972 */ 1973static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 1974{ 1975 idetape_tape_t *tape = drive->driver_data; 1976 struct ide_atapi_pc pc; 1977 int i, retval; 1978 1979 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 1980 mt_op, mt_count); 1981 1982 switch (mt_op) { 1983 case MTFSF: 1984 case MTFSFM: 1985 case MTBSF: 1986 case MTBSFM: 1987 if (!mt_count) 1988 return 0; 1989 return idetape_space_over_filemarks(drive, mt_op, mt_count); 1990 default: 1991 break; 1992 } 1993 1994 switch (mt_op) { 1995 case MTWEOF: 1996 if (tape->write_prot) 1997 return -EACCES; 1998 ide_tape_discard_merge_buffer(drive, 1); 1999 for (i = 0; i < mt_count; i++) { 2000 retval = idetape_write_filemark(drive); 2001 if (retval) 2002 return retval; 2003 } 2004 return 0; 2005 case MTREW: 2006 ide_tape_discard_merge_buffer(drive, 0); 2007 if (idetape_rewind_tape(drive)) 2008 return -EIO; 2009 return 0; 2010 case MTLOAD: 2011 ide_tape_discard_merge_buffer(drive, 0); 2012 idetape_create_load_unload_cmd(drive, &pc, 2013 IDETAPE_LU_LOAD_MASK); 2014 return idetape_queue_pc_tail(drive, &pc); 2015 case MTUNLOAD: 2016 case MTOFFL: 2017 /* 2018 * If door is locked, attempt to unlock before 2019 * attempting to eject. 2020 */ 2021 if (tape->door_locked) { 2022 if (idetape_create_prevent_cmd(drive, &pc, 0)) 2023 if (!idetape_queue_pc_tail(drive, &pc)) 2024 tape->door_locked = DOOR_UNLOCKED; 2025 } 2026 ide_tape_discard_merge_buffer(drive, 0); 2027 idetape_create_load_unload_cmd(drive, &pc, 2028 !IDETAPE_LU_LOAD_MASK); 2029 retval = idetape_queue_pc_tail(drive, &pc); 2030 if (!retval) 2031 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 2032 return retval; 2033 case MTNOP: 2034 ide_tape_discard_merge_buffer(drive, 0); 2035 return idetape_flush_tape_buffers(drive); 2036 case MTRETEN: 2037 ide_tape_discard_merge_buffer(drive, 0); 2038 idetape_create_load_unload_cmd(drive, &pc, 2039 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 2040 return idetape_queue_pc_tail(drive, &pc); 2041 case MTEOM: 2042 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 2043 return idetape_queue_pc_tail(drive, &pc); 2044 case MTERASE: 2045 (void)idetape_rewind_tape(drive); 2046 idetape_create_erase_cmd(&pc); 2047 return idetape_queue_pc_tail(drive, &pc); 2048 case MTSETBLK: 2049 if (mt_count) { 2050 if (mt_count < tape->blk_size || 2051 mt_count % tape->blk_size) 2052 return -EIO; 2053 tape->user_bs_factor = mt_count / tape->blk_size; 2054 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2055 } else 2056 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2057 return 0; 2058 case MTSEEK: 2059 ide_tape_discard_merge_buffer(drive, 0); 2060 return idetape_position_tape(drive, 2061 mt_count * tape->user_bs_factor, tape->partition, 0); 2062 case MTSETPART: 2063 ide_tape_discard_merge_buffer(drive, 0); 2064 return idetape_position_tape(drive, 0, mt_count, 0); 2065 case MTFSR: 2066 case MTBSR: 2067 case MTLOCK: 2068 if (!idetape_create_prevent_cmd(drive, &pc, 1)) 2069 return 0; 2070 retval = idetape_queue_pc_tail(drive, &pc); 2071 if (retval) 2072 return retval; 2073 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 2074 return 0; 2075 case MTUNLOCK: 2076 if (!idetape_create_prevent_cmd(drive, &pc, 0)) 2077 return 0; 2078 retval = idetape_queue_pc_tail(drive, &pc); 2079 if (retval) 2080 return retval; 2081 tape->door_locked = DOOR_UNLOCKED; 2082 return 0; 2083 default: 2084 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 2085 mt_op); 2086 return -EIO; 2087 } 2088} 2089 2090/* 2091 * Our character device ioctls. General mtio.h magnetic io commands are 2092 * supported here, and not in the corresponding block interface. Our own 2093 * ide-tape ioctls are supported on both interfaces. 2094 */ 2095static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 2096 unsigned int cmd, unsigned long arg) 2097{ 2098 struct ide_tape_obj *tape = ide_tape_f(file); 2099 ide_drive_t *drive = tape->drive; 2100 struct mtop mtop; 2101 struct mtget mtget; 2102 struct mtpos mtpos; 2103 int block_offset = 0, position = tape->first_frame; 2104 void __user *argp = (void __user *)arg; 2105 2106 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 2107 2108 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 2109 ide_tape_flush_merge_buffer(drive); 2110 idetape_flush_tape_buffers(drive); 2111 } 2112 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 2113 block_offset = tape->merge_bh_size / 2114 (tape->blk_size * tape->user_bs_factor); 2115 position = idetape_read_position(drive); 2116 if (position < 0) 2117 return -EIO; 2118 } 2119 switch (cmd) { 2120 case MTIOCTOP: 2121 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 2122 return -EFAULT; 2123 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 2124 case MTIOCGET: 2125 memset(&mtget, 0, sizeof(struct mtget)); 2126 mtget.mt_type = MT_ISSCSI2; 2127 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 2128 mtget.mt_dsreg = 2129 ((tape->blk_size * tape->user_bs_factor) 2130 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 2131 2132 if (tape->drv_write_prot) 2133 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 2134 2135 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 2136 return -EFAULT; 2137 return 0; 2138 case MTIOCPOS: 2139 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 2140 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 2141 return -EFAULT; 2142 return 0; 2143 default: 2144 if (tape->chrdev_dir == IDETAPE_DIR_READ) 2145 ide_tape_discard_merge_buffer(drive, 1); 2146 return idetape_blkdev_ioctl(drive, cmd, arg); 2147 } 2148} 2149 2150/* 2151 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 2152 * block size with the reported value. 2153 */ 2154static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 2155{ 2156 idetape_tape_t *tape = drive->driver_data; 2157 struct ide_atapi_pc pc; 2158 2159 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 2160 if (idetape_queue_pc_tail(drive, &pc)) { 2161 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 2162 if (tape->blk_size == 0) { 2163 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 2164 "block size, assuming 32k\n"); 2165 tape->blk_size = 32768; 2166 } 2167 return; 2168 } 2169 tape->blk_size = (pc.buf[4 + 5] << 16) + 2170 (pc.buf[4 + 6] << 8) + 2171 pc.buf[4 + 7]; 2172 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 2173} 2174 2175static int idetape_chrdev_open(struct inode *inode, struct file *filp) 2176{ 2177 unsigned int minor = iminor(inode), i = minor & ~0xc0; 2178 ide_drive_t *drive; 2179 idetape_tape_t *tape; 2180 struct ide_atapi_pc pc; 2181 int retval; 2182 2183 if (i >= MAX_HWIFS * MAX_DRIVES) 2184 return -ENXIO; 2185 2186 lock_kernel(); 2187 tape = ide_tape_chrdev_get(i); 2188 if (!tape) { 2189 unlock_kernel(); 2190 return -ENXIO; 2191 } 2192 2193 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2194 2195 /* 2196 * We really want to do nonseekable_open(inode, filp); here, but some 2197 * versions of tar incorrectly call lseek on tapes and bail out if that 2198 * fails. So we disallow pread() and pwrite(), but permit lseeks. 2199 */ 2200 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 2201 2202 drive = tape->drive; 2203 2204 filp->private_data = tape; 2205 2206 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) { 2207 retval = -EBUSY; 2208 goto out_put_tape; 2209 } 2210 2211 retval = idetape_wait_ready(drive, 60 * HZ); 2212 if (retval) { 2213 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2214 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 2215 goto out_put_tape; 2216 } 2217 2218 idetape_read_position(drive); 2219 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags)) 2220 (void)idetape_rewind_tape(drive); 2221 2222 /* Read block size and write protect status from drive. */ 2223 ide_tape_get_bsize_from_bdesc(drive); 2224 2225 /* Set write protect flag if device is opened as read-only. */ 2226 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 2227 tape->write_prot = 1; 2228 else 2229 tape->write_prot = tape->drv_write_prot; 2230 2231 /* Make sure drive isn't write protected if user wants to write. */ 2232 if (tape->write_prot) { 2233 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 2234 (filp->f_flags & O_ACCMODE) == O_RDWR) { 2235 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2236 retval = -EROFS; 2237 goto out_put_tape; 2238 } 2239 } 2240 2241 /* Lock the tape drive door so user can't eject. */ 2242 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2243 if (idetape_create_prevent_cmd(drive, &pc, 1)) { 2244 if (!idetape_queue_pc_tail(drive, &pc)) { 2245 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 2246 tape->door_locked = DOOR_LOCKED; 2247 } 2248 } 2249 } 2250 unlock_kernel(); 2251 return 0; 2252 2253out_put_tape: 2254 ide_tape_put(tape); 2255 unlock_kernel(); 2256 return retval; 2257} 2258 2259static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 2260{ 2261 idetape_tape_t *tape = drive->driver_data; 2262 2263 ide_tape_flush_merge_buffer(drive); 2264 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 2265 if (tape->merge_bh != NULL) { 2266 idetape_pad_zeros(drive, tape->blk_size * 2267 (tape->user_bs_factor - 1)); 2268 ide_tape_kfree_buffer(tape); 2269 tape->merge_bh = NULL; 2270 } 2271 idetape_write_filemark(drive); 2272 idetape_flush_tape_buffers(drive); 2273 idetape_flush_tape_buffers(drive); 2274} 2275 2276static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2277{ 2278 struct ide_tape_obj *tape = ide_tape_f(filp); 2279 ide_drive_t *drive = tape->drive; 2280 struct ide_atapi_pc pc; 2281 unsigned int minor = iminor(inode); 2282 2283 lock_kernel(); 2284 tape = drive->driver_data; 2285 2286 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2287 2288 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2289 idetape_write_release(drive, minor); 2290 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2291 if (minor < 128) 2292 ide_tape_discard_merge_buffer(drive, 1); 2293 } 2294 2295 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags)) 2296 (void) idetape_rewind_tape(drive); 2297 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2298 if (tape->door_locked == DOOR_LOCKED) { 2299 if (idetape_create_prevent_cmd(drive, &pc, 0)) { 2300 if (!idetape_queue_pc_tail(drive, &pc)) 2301 tape->door_locked = DOOR_UNLOCKED; 2302 } 2303 } 2304 } 2305 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2306 ide_tape_put(tape); 2307 unlock_kernel(); 2308 return 0; 2309} 2310 2311/* 2312 * check the contents of the ATAPI IDENTIFY command results. We return: 2313 * 2314 * 1 - If the tape can be supported by us, based on the information we have so 2315 * far. 2316 * 2317 * 0 - If this tape driver is not currently supported by us. 2318 */ 2319static int idetape_identify_device(ide_drive_t *drive) 2320{ 2321 u8 gcw[2], protocol, device_type, removable, packet_size; 2322 2323 if (drive->id_read == 0) 2324 return 1; 2325 2326 *((unsigned short *) &gcw) = drive->id->config; 2327 2328 protocol = (gcw[1] & 0xC0) >> 6; 2329 device_type = gcw[1] & 0x1F; 2330 removable = !!(gcw[0] & 0x80); 2331 packet_size = gcw[0] & 0x3; 2332 2333 /* Check that we can support this device */ 2334 if (protocol != 2) 2335 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n", 2336 protocol); 2337 else if (device_type != 1) 2338 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set " 2339 "to tape\n", device_type); 2340 else if (!removable) 2341 printk(KERN_ERR "ide-tape: The removable flag is not set\n"); 2342 else if (packet_size != 0) { 2343 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12" 2344 " bytes\n", packet_size); 2345 } else 2346 return 1; 2347 return 0; 2348} 2349 2350static void idetape_get_inquiry_results(ide_drive_t *drive) 2351{ 2352 idetape_tape_t *tape = drive->driver_data; 2353 struct ide_atapi_pc pc; 2354 char fw_rev[6], vendor_id[10], product_id[18]; 2355 2356 idetape_create_inquiry_cmd(&pc); 2357 if (idetape_queue_pc_tail(drive, &pc)) { 2358 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2359 tape->name); 2360 return; 2361 } 2362 memcpy(vendor_id, &pc.buf[8], 8); 2363 memcpy(product_id, &pc.buf[16], 16); 2364 memcpy(fw_rev, &pc.buf[32], 4); 2365 2366 ide_fixstring(vendor_id, 10, 0); 2367 ide_fixstring(product_id, 18, 0); 2368 ide_fixstring(fw_rev, 6, 0); 2369 2370 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n", 2371 drive->name, tape->name, vendor_id, product_id, fw_rev); 2372} 2373 2374/* 2375 * Ask the tape about its various parameters. In particular, we will adjust our 2376 * data transfer buffer size to the recommended value as returned by the tape. 2377 */ 2378static void idetape_get_mode_sense_results(ide_drive_t *drive) 2379{ 2380 idetape_tape_t *tape = drive->driver_data; 2381 struct ide_atapi_pc pc; 2382 u8 *caps; 2383 u8 speed, max_speed; 2384 2385 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2386 if (idetape_queue_pc_tail(drive, &pc)) { 2387 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2388 " some default values\n"); 2389 tape->blk_size = 512; 2390 put_unaligned(52, (u16 *)&tape->caps[12]); 2391 put_unaligned(540, (u16 *)&tape->caps[14]); 2392 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2393 return; 2394 } 2395 caps = pc.buf + 4 + pc.buf[3]; 2396 2397 /* convert to host order and save for later use */ 2398 speed = be16_to_cpu(*(u16 *)&caps[14]); 2399 max_speed = be16_to_cpu(*(u16 *)&caps[8]); 2400 2401 put_unaligned(max_speed, (u16 *)&caps[8]); 2402 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]); 2403 put_unaligned(speed, (u16 *)&caps[14]); 2404 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]); 2405 2406 if (!speed) { 2407 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2408 "(assuming 650KB/sec)\n", drive->name); 2409 put_unaligned(650, (u16 *)&caps[14]); 2410 } 2411 if (!max_speed) { 2412 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2413 "(assuming 650KB/sec)\n", drive->name); 2414 put_unaligned(650, (u16 *)&caps[8]); 2415 } 2416 2417 memcpy(&tape->caps, caps, 20); 2418 if (caps[7] & 0x02) 2419 tape->blk_size = 512; 2420 else if (caps[7] & 0x04) 2421 tape->blk_size = 1024; 2422} 2423 2424#ifdef CONFIG_IDE_PROC_FS 2425static void idetape_add_settings(ide_drive_t *drive) 2426{ 2427 idetape_tape_t *tape = drive->driver_data; 2428 2429 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2430 1, 2, (u16 *)&tape->caps[16], NULL); 2431 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2432 1, 1, (u16 *)&tape->caps[14], NULL); 2433 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff, 2434 1, 1024, &tape->buffer_size, NULL); 2435 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN, 2436 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq, 2437 NULL); 2438 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1, 2439 1, &drive->dsc_overlap, NULL); 2440 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff, 2441 1, 1, &tape->avg_speed, NULL); 2442 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1, 2443 1, &tape->debug_mask, NULL); 2444} 2445#else 2446static inline void idetape_add_settings(ide_drive_t *drive) { ; } 2447#endif 2448 2449/* 2450 * The function below is called to: 2451 * 2452 * 1. Initialize our various state variables. 2453 * 2. Ask the tape for its capabilities. 2454 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2455 * is chosen based on the recommendation which we received in step 2. 2456 * 2457 * Note that at this point ide.c already assigned us an irq, so that we can 2458 * queue requests here and wait for their completion. 2459 */ 2460static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2461{ 2462 unsigned long t; 2463 int speed; 2464 int buffer_size; 2465 u8 gcw[2]; 2466 u16 *ctl = (u16 *)&tape->caps[12]; 2467 2468 spin_lock_init(&tape->lock); 2469 drive->dsc_overlap = 1; 2470 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2471 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2472 tape->name); 2473 drive->dsc_overlap = 0; 2474 } 2475 /* Seagate Travan drives do not support DSC overlap. */ 2476 if (strstr(drive->id->model, "Seagate STT3401")) 2477 drive->dsc_overlap = 0; 2478 tape->minor = minor; 2479 tape->name[0] = 'h'; 2480 tape->name[1] = 't'; 2481 tape->name[2] = '0' + minor; 2482 tape->chrdev_dir = IDETAPE_DIR_NONE; 2483 tape->pc = tape->pc_stack; 2484 *((unsigned short *) &gcw) = drive->id->config; 2485 2486 /* Command packet DRQ type */ 2487 if (((gcw[0] & 0x60) >> 5) == 1) 2488 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags); 2489 2490 idetape_get_inquiry_results(drive); 2491 idetape_get_mode_sense_results(drive); 2492 ide_tape_get_bsize_from_bdesc(drive); 2493 tape->user_bs_factor = 1; 2494 tape->buffer_size = *ctl * tape->blk_size; 2495 while (tape->buffer_size > 0xffff) { 2496 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2497 *ctl /= 2; 2498 tape->buffer_size = *ctl * tape->blk_size; 2499 } 2500 buffer_size = tape->buffer_size; 2501 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2502 if (buffer_size % PAGE_SIZE) { 2503 tape->pages_per_buffer++; 2504 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2505 } 2506 2507 /* select the "best" DSC read/write polling freq */ 2508 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2509 2510 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2511 2512 /* 2513 * Ensure that the number we got makes sense; limit it within 2514 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2515 */ 2516 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN, 2517 IDETAPE_DSC_RW_MAX); 2518 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2519 "%lums tDSC%s\n", 2520 drive->name, tape->name, *(u16 *)&tape->caps[14], 2521 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2522 tape->buffer_size / 1024, 2523 tape->best_dsc_rw_freq * 1000 / HZ, 2524 drive->using_dma ? ", DMA":""); 2525 2526 idetape_add_settings(drive); 2527} 2528 2529static void ide_tape_remove(ide_drive_t *drive) 2530{ 2531 idetape_tape_t *tape = drive->driver_data; 2532 2533 ide_proc_unregister_driver(drive, tape->driver); 2534 2535 ide_unregister_region(tape->disk); 2536 2537 ide_tape_put(tape); 2538} 2539 2540static void ide_tape_release(struct kref *kref) 2541{ 2542 struct ide_tape_obj *tape = to_ide_tape(kref); 2543 ide_drive_t *drive = tape->drive; 2544 struct gendisk *g = tape->disk; 2545 2546 BUG_ON(tape->merge_bh_size); 2547 2548 drive->dsc_overlap = 0; 2549 drive->driver_data = NULL; 2550 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2551 device_destroy(idetape_sysfs_class, 2552 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2553 idetape_devs[tape->minor] = NULL; 2554 g->private_data = NULL; 2555 put_disk(g); 2556 kfree(tape); 2557} 2558 2559#ifdef CONFIG_IDE_PROC_FS 2560static int proc_idetape_read_name 2561 (char *page, char **start, off_t off, int count, int *eof, void *data) 2562{ 2563 ide_drive_t *drive = (ide_drive_t *) data; 2564 idetape_tape_t *tape = drive->driver_data; 2565 char *out = page; 2566 int len; 2567 2568 len = sprintf(out, "%s\n", tape->name); 2569 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2570} 2571 2572static ide_proc_entry_t idetape_proc[] = { 2573 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2574 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2575 { NULL, 0, NULL, NULL } 2576}; 2577#endif 2578 2579static int ide_tape_probe(ide_drive_t *); 2580 2581static ide_driver_t idetape_driver = { 2582 .gen_driver = { 2583 .owner = THIS_MODULE, 2584 .name = "ide-tape", 2585 .bus = &ide_bus_type, 2586 }, 2587 .probe = ide_tape_probe, 2588 .remove = ide_tape_remove, 2589 .version = IDETAPE_VERSION, 2590 .media = ide_tape, 2591 .supports_dsc_overlap = 1, 2592 .do_request = idetape_do_request, 2593 .end_request = idetape_end_request, 2594 .error = __ide_error, 2595#ifdef CONFIG_IDE_PROC_FS 2596 .proc = idetape_proc, 2597#endif 2598}; 2599 2600/* Our character device supporting functions, passed to register_chrdev. */ 2601static const struct file_operations idetape_fops = { 2602 .owner = THIS_MODULE, 2603 .read = idetape_chrdev_read, 2604 .write = idetape_chrdev_write, 2605 .ioctl = idetape_chrdev_ioctl, 2606 .open = idetape_chrdev_open, 2607 .release = idetape_chrdev_release, 2608}; 2609 2610static int idetape_open(struct inode *inode, struct file *filp) 2611{ 2612 struct gendisk *disk = inode->i_bdev->bd_disk; 2613 struct ide_tape_obj *tape; 2614 2615 tape = ide_tape_get(disk); 2616 if (!tape) 2617 return -ENXIO; 2618 2619 return 0; 2620} 2621 2622static int idetape_release(struct inode *inode, struct file *filp) 2623{ 2624 struct gendisk *disk = inode->i_bdev->bd_disk; 2625 struct ide_tape_obj *tape = ide_tape_g(disk); 2626 2627 ide_tape_put(tape); 2628 2629 return 0; 2630} 2631 2632static int idetape_ioctl(struct inode *inode, struct file *file, 2633 unsigned int cmd, unsigned long arg) 2634{ 2635 struct block_device *bdev = inode->i_bdev; 2636 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 2637 ide_drive_t *drive = tape->drive; 2638 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 2639 if (err == -EINVAL) 2640 err = idetape_blkdev_ioctl(drive, cmd, arg); 2641 return err; 2642} 2643 2644static struct block_device_operations idetape_block_ops = { 2645 .owner = THIS_MODULE, 2646 .open = idetape_open, 2647 .release = idetape_release, 2648 .ioctl = idetape_ioctl, 2649}; 2650 2651static int ide_tape_probe(ide_drive_t *drive) 2652{ 2653 idetape_tape_t *tape; 2654 struct gendisk *g; 2655 int minor; 2656 2657 if (!strstr("ide-tape", drive->driver_req)) 2658 goto failed; 2659 if (!drive->present) 2660 goto failed; 2661 if (drive->media != ide_tape) 2662 goto failed; 2663 if (!idetape_identify_device(drive)) { 2664 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2665 " the driver\n", drive->name); 2666 goto failed; 2667 } 2668 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2669 if (tape == NULL) { 2670 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2671 drive->name); 2672 goto failed; 2673 } 2674 2675 g = alloc_disk(1 << PARTN_BITS); 2676 if (!g) 2677 goto out_free_tape; 2678 2679 ide_init_disk(g, drive); 2680 2681 ide_proc_register_driver(drive, &idetape_driver); 2682 2683 kref_init(&tape->kref); 2684 2685 tape->drive = drive; 2686 tape->driver = &idetape_driver; 2687 tape->disk = g; 2688 2689 g->private_data = &tape->driver; 2690 2691 drive->driver_data = tape; 2692 2693 mutex_lock(&idetape_ref_mutex); 2694 for (minor = 0; idetape_devs[minor]; minor++) 2695 ; 2696 idetape_devs[minor] = tape; 2697 mutex_unlock(&idetape_ref_mutex); 2698 2699 idetape_setup(drive, tape, minor); 2700 2701 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2702 MKDEV(IDETAPE_MAJOR, minor), NULL, 2703 "%s", tape->name); 2704 device_create_drvdata(idetape_sysfs_class, &drive->gendev, 2705 MKDEV(IDETAPE_MAJOR, minor + 128), NULL, 2706 "n%s", tape->name); 2707 2708 g->fops = &idetape_block_ops; 2709 ide_register_region(g); 2710 2711 return 0; 2712 2713out_free_tape: 2714 kfree(tape); 2715failed: 2716 return -ENODEV; 2717} 2718 2719static void __exit idetape_exit(void) 2720{ 2721 driver_unregister(&idetape_driver.gen_driver); 2722 class_destroy(idetape_sysfs_class); 2723 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2724} 2725 2726static int __init idetape_init(void) 2727{ 2728 int error = 1; 2729 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2730 if (IS_ERR(idetape_sysfs_class)) { 2731 idetape_sysfs_class = NULL; 2732 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2733 error = -EBUSY; 2734 goto out; 2735 } 2736 2737 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2738 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2739 " interface\n"); 2740 error = -EBUSY; 2741 goto out_free_class; 2742 } 2743 2744 error = driver_register(&idetape_driver.gen_driver); 2745 if (error) 2746 goto out_free_driver; 2747 2748 return 0; 2749 2750out_free_driver: 2751 driver_unregister(&idetape_driver.gen_driver); 2752out_free_class: 2753 class_destroy(idetape_sysfs_class); 2754out: 2755 return error; 2756} 2757 2758MODULE_ALIAS("ide:*m-tape*"); 2759module_init(idetape_init); 2760module_exit(idetape_exit); 2761MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 2762MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 2763MODULE_LICENSE("GPL"); 2764