ide-tape.c revision 1fc142589e58b20a67582974b8848595a2c7432e
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/* Read/Write error simulation */ 148#define SIMULATE_ERRORS 0 149 150/* tape directions */ 151enum { 152 IDETAPE_DIR_NONE = (1 << 0), 153 IDETAPE_DIR_READ = (1 << 1), 154 IDETAPE_DIR_WRITE = (1 << 2), 155}; 156 157struct idetape_bh { 158 u32 b_size; 159 atomic_t b_count; 160 struct idetape_bh *b_reqnext; 161 char *b_data; 162}; 163 164/* Tape door status */ 165#define DOOR_UNLOCKED 0 166#define DOOR_LOCKED 1 167#define DOOR_EXPLICITLY_LOCKED 2 168 169/* Some defines for the SPACE command */ 170#define IDETAPE_SPACE_OVER_FILEMARK 1 171#define IDETAPE_SPACE_TO_EOD 3 172 173/* Some defines for the LOAD UNLOAD command */ 174#define IDETAPE_LU_LOAD_MASK 1 175#define IDETAPE_LU_RETENSION_MASK 2 176#define IDETAPE_LU_EOT_MASK 4 177 178/* 179 * Special requests for our block device strategy routine. 180 * 181 * In order to service a character device command, we add special requests to 182 * the tail of our block device request queue and wait for their completion. 183 */ 184 185enum { 186 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */ 187 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */ 188 REQ_IDETAPE_READ = (1 << 2), 189 REQ_IDETAPE_WRITE = (1 << 3), 190}; 191 192/* Error codes returned in rq->errors to the higher part of the driver. */ 193#define IDETAPE_ERROR_GENERAL 101 194#define IDETAPE_ERROR_FILEMARK 102 195#define IDETAPE_ERROR_EOD 103 196 197/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 198#define IDETAPE_BLOCK_DESCRIPTOR 0 199#define IDETAPE_CAPABILITIES_PAGE 0x2a 200 201/* Tape flag bits values. */ 202enum { 203 IDETAPE_FLAG_IGNORE_DSC = (1 << 0), 204 /* 0 When the tape position is unknown */ 205 IDETAPE_FLAG_ADDRESS_VALID = (1 << 1), 206 /* Device already opened */ 207 IDETAPE_FLAG_BUSY = (1 << 2), 208 /* Attempt to auto-detect the current user block size */ 209 IDETAPE_FLAG_DETECT_BS = (1 << 3), 210 /* Currently on a filemark */ 211 IDETAPE_FLAG_FILEMARK = (1 << 4), 212 /* DRQ interrupt device */ 213 IDETAPE_FLAG_DRQ_INTERRUPT = (1 << 5), 214 /* 0 = no tape is loaded, so we don't rewind after ejecting */ 215 IDETAPE_FLAG_MEDIUM_PRESENT = (1 << 6), 216}; 217 218/* 219 * Most of our global data which we need to save even as we leave the driver due 220 * to an interrupt or a timer event is stored in the struct defined below. 221 */ 222typedef struct ide_tape_obj { 223 ide_drive_t *drive; 224 ide_driver_t *driver; 225 struct gendisk *disk; 226 struct kref kref; 227 228 /* 229 * Since a typical character device operation requires more 230 * than one packet command, we provide here enough memory 231 * for the maximum of interconnected packet commands. 232 * The packet commands are stored in the circular array pc_stack. 233 * pc_stack_index points to the last used entry, and warps around 234 * to the start when we get to the last array entry. 235 * 236 * pc points to the current processed packet command. 237 * 238 * failed_pc points to the last failed packet command, or contains 239 * NULL if we do not need to retry any packet command. This is 240 * required since an additional packet command is needed before the 241 * retry, to get detailed information on what went wrong. 242 */ 243 /* Current packet command */ 244 struct ide_atapi_pc *pc; 245 /* Last failed packet command */ 246 struct ide_atapi_pc *failed_pc; 247 /* Packet command stack */ 248 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK]; 249 /* Next free packet command storage space */ 250 int pc_stack_index; 251 struct request rq_stack[IDETAPE_PC_STACK]; 252 /* We implement a circular array */ 253 int rq_stack_index; 254 255 /* 256 * DSC polling variables. 257 * 258 * While polling for DSC we use postponed_rq to postpone the current 259 * request so that ide.c will be able to service pending requests on the 260 * other device. Note that at most we will have only one DSC (usually 261 * data transfer) request in the device request queue. 262 */ 263 struct request *postponed_rq; 264 /* The time in which we started polling for DSC */ 265 unsigned long dsc_polling_start; 266 /* Timer used to poll for dsc */ 267 struct timer_list dsc_timer; 268 /* Read/Write dsc polling frequency */ 269 unsigned long best_dsc_rw_freq; 270 unsigned long dsc_poll_freq; 271 unsigned long dsc_timeout; 272 273 /* Read position information */ 274 u8 partition; 275 /* Current block */ 276 unsigned int first_frame; 277 278 /* Last error information */ 279 u8 sense_key, asc, ascq; 280 281 /* Character device operation */ 282 unsigned int minor; 283 /* device name */ 284 char name[4]; 285 /* Current character device data transfer direction */ 286 u8 chrdev_dir; 287 288 /* tape block size, usually 512 or 1024 bytes */ 289 unsigned short blk_size; 290 int user_bs_factor; 291 292 /* Copy of the tape's Capabilities and Mechanical Page */ 293 u8 caps[20]; 294 295 /* 296 * Active data transfer request parameters. 297 * 298 * At most, there is only one ide-tape originated data transfer request 299 * in the device request queue. This allows ide.c to easily service 300 * requests from the other device when we postpone our active request. 301 */ 302 303 /* Data buffer size chosen based on the tape's recommendation */ 304 int buffer_size; 305 /* merge buffer */ 306 struct idetape_bh *merge_bh; 307 /* size of the merge buffer */ 308 int merge_bh_size; 309 /* pointer to current buffer head within the merge buffer */ 310 struct idetape_bh *bh; 311 char *b_data; 312 int b_count; 313 314 int pages_per_buffer; 315 /* Wasted space in each stage */ 316 int excess_bh_size; 317 318 /* Status/Action flags: long for set_bit */ 319 unsigned long flags; 320 /* protects the ide-tape queue */ 321 spinlock_t lock; 322 323 /* Measures average tape speed */ 324 unsigned long avg_time; 325 int avg_size; 326 int avg_speed; 327 328 /* the door is currently locked */ 329 int door_locked; 330 /* the tape hardware is write protected */ 331 char drv_write_prot; 332 /* the tape is write protected (hardware or opened as read-only) */ 333 char write_prot; 334 335 u32 debug_mask; 336} idetape_tape_t; 337 338static DEFINE_MUTEX(idetape_ref_mutex); 339 340static struct class *idetape_sysfs_class; 341 342#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref) 343 344#define ide_tape_g(disk) \ 345 container_of((disk)->private_data, struct ide_tape_obj, driver) 346 347static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 348{ 349 struct ide_tape_obj *tape = NULL; 350 351 mutex_lock(&idetape_ref_mutex); 352 tape = ide_tape_g(disk); 353 if (tape) 354 kref_get(&tape->kref); 355 mutex_unlock(&idetape_ref_mutex); 356 return tape; 357} 358 359static void ide_tape_release(struct kref *); 360 361static void ide_tape_put(struct ide_tape_obj *tape) 362{ 363 mutex_lock(&idetape_ref_mutex); 364 kref_put(&tape->kref, ide_tape_release); 365 mutex_unlock(&idetape_ref_mutex); 366} 367 368/* 369 * The variables below are used for the character device interface. Additional 370 * state variables are defined in our ide_drive_t structure. 371 */ 372static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES]; 373 374#define ide_tape_f(file) ((file)->private_data) 375 376static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 377{ 378 struct ide_tape_obj *tape = NULL; 379 380 mutex_lock(&idetape_ref_mutex); 381 tape = idetape_devs[i]; 382 if (tape) 383 kref_get(&tape->kref); 384 mutex_unlock(&idetape_ref_mutex); 385 return tape; 386} 387 388static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 389 unsigned int bcount) 390{ 391 struct idetape_bh *bh = pc->bh; 392 int count; 393 394 while (bcount) { 395 if (bh == NULL) { 396 printk(KERN_ERR "ide-tape: bh == NULL in " 397 "idetape_input_buffers\n"); 398 ide_atapi_discard_data(drive, bcount); 399 return; 400 } 401 count = min( 402 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)), 403 bcount); 404 drive->hwif->input_data(drive, NULL, bh->b_data + 405 atomic_read(&bh->b_count), count); 406 bcount -= count; 407 atomic_add(count, &bh->b_count); 408 if (atomic_read(&bh->b_count) == bh->b_size) { 409 bh = bh->b_reqnext; 410 if (bh) 411 atomic_set(&bh->b_count, 0); 412 } 413 } 414 pc->bh = bh; 415} 416 417static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc, 418 unsigned int bcount) 419{ 420 struct idetape_bh *bh = pc->bh; 421 int count; 422 423 while (bcount) { 424 if (bh == NULL) { 425 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 426 __func__); 427 return; 428 } 429 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 430 drive->hwif->output_data(drive, NULL, pc->b_data, count); 431 bcount -= count; 432 pc->b_data += count; 433 pc->b_count -= count; 434 if (!pc->b_count) { 435 bh = bh->b_reqnext; 436 pc->bh = bh; 437 if (bh) { 438 pc->b_data = bh->b_data; 439 pc->b_count = atomic_read(&bh->b_count); 440 } 441 } 442 } 443} 444 445static void idetape_update_buffers(struct ide_atapi_pc *pc) 446{ 447 struct idetape_bh *bh = pc->bh; 448 int count; 449 unsigned int bcount = pc->xferred; 450 451 if (pc->flags & PC_FLAG_WRITING) 452 return; 453 while (bcount) { 454 if (bh == NULL) { 455 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 456 __func__); 457 return; 458 } 459 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 460 atomic_set(&bh->b_count, count); 461 if (atomic_read(&bh->b_count) == bh->b_size) 462 bh = bh->b_reqnext; 463 bcount -= count; 464 } 465 pc->bh = bh; 466} 467 468/* 469 * idetape_next_pc_storage returns a pointer to a place in which we can 470 * safely store a packet command, even though we intend to leave the 471 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet 472 * commands is allocated at initialization time. 473 */ 474static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive) 475{ 476 idetape_tape_t *tape = drive->driver_data; 477 478 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index); 479 480 if (tape->pc_stack_index == IDETAPE_PC_STACK) 481 tape->pc_stack_index = 0; 482 return (&tape->pc_stack[tape->pc_stack_index++]); 483} 484 485/* 486 * idetape_next_rq_storage is used along with idetape_next_pc_storage. 487 * Since we queue packet commands in the request queue, we need to 488 * allocate a request, along with the allocation of a packet command. 489 */ 490 491/************************************************************** 492 * * 493 * This should get fixed to use kmalloc(.., GFP_ATOMIC) * 494 * followed later on by kfree(). -ml * 495 * * 496 **************************************************************/ 497 498static struct request *idetape_next_rq_storage(ide_drive_t *drive) 499{ 500 idetape_tape_t *tape = drive->driver_data; 501 502 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index); 503 504 if (tape->rq_stack_index == IDETAPE_PC_STACK) 505 tape->rq_stack_index = 0; 506 return (&tape->rq_stack[tape->rq_stack_index++]); 507} 508 509static void idetape_init_pc(struct ide_atapi_pc *pc) 510{ 511 memset(pc->c, 0, 12); 512 pc->retries = 0; 513 pc->flags = 0; 514 pc->req_xfer = 0; 515 pc->buf = pc->pc_buf; 516 pc->buf_size = IDETAPE_PC_BUFFER_SIZE; 517 pc->bh = NULL; 518 pc->b_data = NULL; 519} 520 521/* 522 * called on each failed packet command retry to analyze the request sense. We 523 * currently do not utilize this information. 524 */ 525static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 526{ 527 idetape_tape_t *tape = drive->driver_data; 528 struct ide_atapi_pc *pc = tape->failed_pc; 529 530 tape->sense_key = sense[2] & 0xF; 531 tape->asc = sense[12]; 532 tape->ascq = sense[13]; 533 534 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 535 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 536 537 /* Correct pc->xferred by asking the tape. */ 538 if (pc->flags & PC_FLAG_DMA_ERROR) { 539 pc->xferred = pc->req_xfer - 540 tape->blk_size * 541 be32_to_cpu(get_unaligned((u32 *)&sense[3])); 542 idetape_update_buffers(pc); 543 } 544 545 /* 546 * If error was the result of a zero-length read or write command, 547 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 548 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 549 */ 550 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 551 /* length == 0 */ 552 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 553 if (tape->sense_key == 5) { 554 /* don't report an error, everything's ok */ 555 pc->error = 0; 556 /* don't retry read/write */ 557 pc->flags |= PC_FLAG_ABORT; 558 } 559 } 560 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 561 pc->error = IDETAPE_ERROR_FILEMARK; 562 pc->flags |= PC_FLAG_ABORT; 563 } 564 if (pc->c[0] == WRITE_6) { 565 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 566 && tape->asc == 0x0 && tape->ascq == 0x2)) { 567 pc->error = IDETAPE_ERROR_EOD; 568 pc->flags |= PC_FLAG_ABORT; 569 } 570 } 571 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 572 if (tape->sense_key == 8) { 573 pc->error = IDETAPE_ERROR_EOD; 574 pc->flags |= PC_FLAG_ABORT; 575 } 576 if (!(pc->flags & PC_FLAG_ABORT) && 577 pc->xferred) 578 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 579 } 580} 581 582/* Free data buffers completely. */ 583static void ide_tape_kfree_buffer(idetape_tape_t *tape) 584{ 585 struct idetape_bh *prev_bh, *bh = tape->merge_bh; 586 587 while (bh) { 588 u32 size = bh->b_size; 589 590 while (size) { 591 unsigned int order = fls(size >> PAGE_SHIFT)-1; 592 593 if (bh->b_data) 594 free_pages((unsigned long)bh->b_data, order); 595 596 size &= (order-1); 597 bh->b_data += (1 << order) * PAGE_SIZE; 598 } 599 prev_bh = bh; 600 bh = bh->b_reqnext; 601 kfree(prev_bh); 602 } 603 kfree(tape->merge_bh); 604} 605 606static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 607{ 608 struct request *rq = HWGROUP(drive)->rq; 609 idetape_tape_t *tape = drive->driver_data; 610 unsigned long flags; 611 int error; 612 613 debug_log(DBG_PROCS, "Enter %s\n", __func__); 614 615 switch (uptodate) { 616 case 0: error = IDETAPE_ERROR_GENERAL; break; 617 case 1: error = 0; break; 618 default: error = uptodate; 619 } 620 rq->errors = error; 621 if (error) 622 tape->failed_pc = NULL; 623 624 if (!blk_special_request(rq)) { 625 ide_end_request(drive, uptodate, nr_sects); 626 return 0; 627 } 628 629 spin_lock_irqsave(&tape->lock, flags); 630 631 ide_end_drive_cmd(drive, 0, 0); 632 633 spin_unlock_irqrestore(&tape->lock, flags); 634 return 0; 635} 636 637static ide_startstop_t idetape_request_sense_callback(ide_drive_t *drive) 638{ 639 idetape_tape_t *tape = drive->driver_data; 640 641 debug_log(DBG_PROCS, "Enter %s\n", __func__); 642 643 if (!tape->pc->error) { 644 idetape_analyze_error(drive, tape->pc->buf); 645 idetape_end_request(drive, 1, 0); 646 } else { 647 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE itself - " 648 "Aborting request!\n"); 649 idetape_end_request(drive, 0, 0); 650 } 651 return ide_stopped; 652} 653 654static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc) 655{ 656 idetape_init_pc(pc); 657 pc->c[0] = REQUEST_SENSE; 658 pc->c[4] = 20; 659 pc->req_xfer = 20; 660 pc->idetape_callback = &idetape_request_sense_callback; 661} 662 663static void idetape_init_rq(struct request *rq, u8 cmd) 664{ 665 memset(rq, 0, sizeof(*rq)); 666 rq->cmd_type = REQ_TYPE_SPECIAL; 667 rq->cmd[0] = cmd; 668} 669 670/* 671 * Generate a new packet command request in front of the request queue, before 672 * the current request, so that it will be processed immediately, on the next 673 * pass through the driver. The function below is called from the request 674 * handling part of the driver (the "bottom" part). Safe storage for the request 675 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that. 676 * 677 * Memory for those requests is pre-allocated at initialization time, and is 678 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for 679 * the maximum possible number of inter-dependent packet commands. 680 * 681 * The higher level of the driver - The ioctl handler and the character device 682 * handling functions should queue request to the lower level part and wait for 683 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail. 684 */ 685static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc, 686 struct request *rq) 687{ 688 struct ide_tape_obj *tape = drive->driver_data; 689 690 idetape_init_rq(rq, REQ_IDETAPE_PC1); 691 rq->buffer = (char *) pc; 692 rq->rq_disk = tape->disk; 693 (void) ide_do_drive_cmd(drive, rq, ide_preempt); 694} 695 696/* 697 * idetape_retry_pc is called when an error was detected during the 698 * last packet command. We queue a request sense packet command in 699 * the head of the request list. 700 */ 701static ide_startstop_t idetape_retry_pc (ide_drive_t *drive) 702{ 703 idetape_tape_t *tape = drive->driver_data; 704 struct ide_atapi_pc *pc; 705 struct request *rq; 706 707 (void)ide_read_error(drive); 708 pc = idetape_next_pc_storage(drive); 709 rq = idetape_next_rq_storage(drive); 710 idetape_create_request_sense_cmd(pc); 711 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 712 idetape_queue_pc_head(drive, pc, rq); 713 return ide_stopped; 714} 715 716/* 717 * Postpone the current request so that ide.c will be able to service requests 718 * from another device on the same hwgroup while we are polling for DSC. 719 */ 720static void idetape_postpone_request(ide_drive_t *drive) 721{ 722 idetape_tape_t *tape = drive->driver_data; 723 724 debug_log(DBG_PROCS, "Enter %s\n", __func__); 725 726 tape->postponed_rq = HWGROUP(drive)->rq; 727 ide_stall_queue(drive, tape->dsc_poll_freq); 728} 729 730typedef void idetape_io_buf(ide_drive_t *, struct ide_atapi_pc *, unsigned int); 731 732/* 733 * This is the usual interrupt handler which will be called during a packet 734 * command. We will transfer some of the data (as requested by the drive) and 735 * will re-point interrupt handler to us. When data transfer is finished, we 736 * will act according to the algorithm described before 737 * idetape_issue_pc. 738 */ 739static ide_startstop_t idetape_pc_intr(ide_drive_t *drive) 740{ 741 ide_hwif_t *hwif = drive->hwif; 742 idetape_tape_t *tape = drive->driver_data; 743 struct ide_atapi_pc *pc = tape->pc; 744 xfer_func_t *xferfunc; 745 idetape_io_buf *iobuf; 746 unsigned int temp; 747#if SIMULATE_ERRORS 748 static int error_sim_count; 749#endif 750 u16 bcount; 751 u8 stat, ireason; 752 753 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__); 754 755 /* Clear the interrupt */ 756 stat = ide_read_status(drive); 757 758 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 759 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) { 760 /* 761 * A DMA error is sometimes expected. For example, 762 * if the tape is crossing a filemark during a 763 * READ command, it will issue an irq and position 764 * itself before the filemark, so that only a partial 765 * data transfer will occur (which causes the DMA 766 * error). In that case, we will later ask the tape 767 * how much bytes of the original request were 768 * actually transferred (we can't receive that 769 * information from the DMA engine on most chipsets). 770 */ 771 772 /* 773 * On the contrary, a DMA error is never expected; 774 * it usually indicates a hardware error or abort. 775 * If the tape crosses a filemark during a READ 776 * command, it will issue an irq and position itself 777 * after the filemark (not before). Only a partial 778 * data transfer will occur, but no DMA error. 779 * (AS, 19 Apr 2001) 780 */ 781 pc->flags |= PC_FLAG_DMA_ERROR; 782 } else { 783 pc->xferred = pc->req_xfer; 784 idetape_update_buffers(pc); 785 } 786 debug_log(DBG_PROCS, "DMA finished\n"); 787 788 } 789 790 /* No more interrupts */ 791 if ((stat & DRQ_STAT) == 0) { 792 debug_log(DBG_SENSE, "Packet command completed, %d bytes" 793 " transferred\n", pc->xferred); 794 795 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 796 local_irq_enable(); 797 798#if SIMULATE_ERRORS 799 if ((pc->c[0] == WRITE_6 || pc->c[0] == READ_6) && 800 (++error_sim_count % 100) == 0) { 801 printk(KERN_INFO "ide-tape: %s: simulating error\n", 802 tape->name); 803 stat |= ERR_STAT; 804 } 805#endif 806 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE) 807 stat &= ~ERR_STAT; 808 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) { 809 /* Error detected */ 810 debug_log(DBG_ERR, "%s: I/O error\n", tape->name); 811 812 if (pc->c[0] == REQUEST_SENSE) { 813 printk(KERN_ERR "ide-tape: I/O error in request" 814 " sense command\n"); 815 return ide_do_reset(drive); 816 } 817 debug_log(DBG_ERR, "[cmd %x]: check condition\n", 818 pc->c[0]); 819 820 /* Retry operation */ 821 return idetape_retry_pc(drive); 822 } 823 pc->error = 0; 824 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) && 825 (stat & SEEK_STAT) == 0) { 826 /* Media access command */ 827 tape->dsc_polling_start = jiffies; 828 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST; 829 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 830 /* Allow ide.c to handle other requests */ 831 idetape_postpone_request(drive); 832 return ide_stopped; 833 } 834 if (tape->failed_pc == pc) 835 tape->failed_pc = NULL; 836 /* Command finished - Call the callback function */ 837 return pc->idetape_callback(drive); 838 } 839 840 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) { 841 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS; 842 printk(KERN_ERR "ide-tape: The tape wants to issue more " 843 "interrupts in DMA mode\n"); 844 printk(KERN_ERR "ide-tape: DMA disabled, reverting to PIO\n"); 845 ide_dma_off(drive); 846 return ide_do_reset(drive); 847 } 848 /* Get the number of bytes to transfer on this interrupt. */ 849 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) | 850 hwif->INB(hwif->io_ports.lbam_addr); 851 852 ireason = hwif->INB(hwif->io_ports.nsect_addr); 853 854 if (ireason & CD) { 855 printk(KERN_ERR "ide-tape: CoD != 0 in %s\n", __func__); 856 return ide_do_reset(drive); 857 } 858 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) { 859 /* Hopefully, we will never get here */ 860 printk(KERN_ERR "ide-tape: We wanted to %s, ", 861 (ireason & IO) ? "Write" : "Read"); 862 printk(KERN_ERR "ide-tape: but the tape wants us to %s !\n", 863 (ireason & IO) ? "Read" : "Write"); 864 return ide_do_reset(drive); 865 } 866 if (!(pc->flags & PC_FLAG_WRITING)) { 867 /* Reading - Check that we have enough space */ 868 temp = pc->xferred + bcount; 869 if (temp > pc->req_xfer) { 870 if (temp > pc->buf_size) { 871 printk(KERN_ERR "ide-tape: The tape wants to " 872 "send us more data than expected " 873 "- discarding data\n"); 874 ide_atapi_discard_data(drive, bcount); 875 ide_set_handler(drive, &idetape_pc_intr, 876 IDETAPE_WAIT_CMD, NULL); 877 return ide_started; 878 } 879 debug_log(DBG_SENSE, "The tape wants to send us more " 880 "data than expected - allowing transfer\n"); 881 } 882 iobuf = &idetape_input_buffers; 883 xferfunc = hwif->input_data; 884 } else { 885 iobuf = &idetape_output_buffers; 886 xferfunc = hwif->output_data; 887 } 888 889 if (pc->bh) 890 iobuf(drive, pc, bcount); 891 else 892 xferfunc(drive, NULL, pc->cur_pos, bcount); 893 894 /* Update the current position */ 895 pc->xferred += bcount; 896 pc->cur_pos += bcount; 897 898 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n", 899 pc->c[0], bcount); 900 901 /* And set the interrupt handler again */ 902 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 903 return ide_started; 904} 905 906/* 907 * Packet Command Interface 908 * 909 * The current Packet Command is available in tape->pc, and will not change 910 * until we finish handling it. Each packet command is associated with a 911 * callback function that will be called when the command is finished. 912 * 913 * The handling will be done in three stages: 914 * 915 * 1. idetape_issue_pc will send the packet command to the drive, and will set 916 * the interrupt handler to idetape_pc_intr. 917 * 918 * 2. On each interrupt, idetape_pc_intr will be called. This step will be 919 * repeated until the device signals us that no more interrupts will be issued. 920 * 921 * 3. ATAPI Tape media access commands have immediate status with a delayed 922 * process. In case of a successful initiation of a media access packet command, 923 * the DSC bit will be set when the actual execution of the command is finished. 924 * Since the tape drive will not issue an interrupt, we have to poll for this 925 * event. In this case, we define the request as "low priority request" by 926 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and 927 * exit the driver. 928 * 929 * ide.c will then give higher priority to requests which originate from the 930 * other device, until will change rq_status to RQ_ACTIVE. 931 * 932 * 4. When the packet command is finished, it will be checked for errors. 933 * 934 * 5. In case an error was found, we queue a request sense packet command in 935 * front of the request queue and retry the operation up to 936 * IDETAPE_MAX_PC_RETRIES times. 937 * 938 * 6. In case no error was found, or we decided to give up and not to retry 939 * again, the callback function will be called and then we will handle the next 940 * request. 941 */ 942static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 943{ 944 ide_hwif_t *hwif = drive->hwif; 945 idetape_tape_t *tape = drive->driver_data; 946 struct ide_atapi_pc *pc = tape->pc; 947 int retries = 100; 948 ide_startstop_t startstop; 949 u8 ireason; 950 951 if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) { 952 printk(KERN_ERR "ide-tape: Strange, packet command initiated " 953 "yet DRQ isn't asserted\n"); 954 return startstop; 955 } 956 ireason = hwif->INB(hwif->io_ports.nsect_addr); 957 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) { 958 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while issuing " 959 "a packet command, retrying\n"); 960 udelay(100); 961 ireason = hwif->INB(hwif->io_ports.nsect_addr); 962 if (retries == 0) { 963 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while " 964 "issuing a packet command, ignoring\n"); 965 ireason |= CD; 966 ireason &= ~IO; 967 } 968 } 969 if ((ireason & CD) == 0 || (ireason & IO)) { 970 printk(KERN_ERR "ide-tape: (IO,CoD) != (0,1) while issuing " 971 "a packet command\n"); 972 return ide_do_reset(drive); 973 } 974 /* Set the interrupt routine */ 975 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 976#ifdef CONFIG_BLK_DEV_IDEDMA 977 /* Begin DMA, if necessary */ 978 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) 979 hwif->dma_ops->dma_start(drive); 980#endif 981 /* Send the actual packet */ 982 hwif->output_data(drive, NULL, pc->c, 12); 983 984 return ide_started; 985} 986 987static ide_startstop_t idetape_issue_pc(ide_drive_t *drive, 988 struct ide_atapi_pc *pc) 989{ 990 ide_hwif_t *hwif = drive->hwif; 991 idetape_tape_t *tape = drive->driver_data; 992 int dma_ok = 0; 993 u16 bcount; 994 995 if (tape->pc->c[0] == REQUEST_SENSE && 996 pc->c[0] == REQUEST_SENSE) { 997 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 998 "Two request sense in serial were issued\n"); 999 } 1000 1001 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 1002 tape->failed_pc = pc; 1003 /* Set the current packet command */ 1004 tape->pc = pc; 1005 1006 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 1007 (pc->flags & PC_FLAG_ABORT)) { 1008 /* 1009 * We will "abort" retrying a packet command in case legitimate 1010 * error code was received (crossing a filemark, or end of the 1011 * media, for example). 1012 */ 1013 if (!(pc->flags & PC_FLAG_ABORT)) { 1014 if (!(pc->c[0] == TEST_UNIT_READY && 1015 tape->sense_key == 2 && tape->asc == 4 && 1016 (tape->ascq == 1 || tape->ascq == 8))) { 1017 printk(KERN_ERR "ide-tape: %s: I/O error, " 1018 "pc = %2x, key = %2x, " 1019 "asc = %2x, ascq = %2x\n", 1020 tape->name, pc->c[0], 1021 tape->sense_key, tape->asc, 1022 tape->ascq); 1023 } 1024 /* Giving up */ 1025 pc->error = IDETAPE_ERROR_GENERAL; 1026 } 1027 tape->failed_pc = NULL; 1028 return pc->idetape_callback(drive); 1029 } 1030 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 1031 1032 pc->retries++; 1033 /* We haven't transferred any data yet */ 1034 pc->xferred = 0; 1035 pc->cur_pos = pc->buf; 1036 /* Request to transfer the entire buffer at once */ 1037 bcount = pc->req_xfer; 1038 1039 if (pc->flags & PC_FLAG_DMA_ERROR) { 1040 pc->flags &= ~PC_FLAG_DMA_ERROR; 1041 printk(KERN_WARNING "ide-tape: DMA disabled, " 1042 "reverting to PIO\n"); 1043 ide_dma_off(drive); 1044 } 1045 if ((pc->flags & PC_FLAG_DMA_RECOMMENDED) && drive->using_dma) 1046 dma_ok = !hwif->dma_ops->dma_setup(drive); 1047 1048 ide_pktcmd_tf_load(drive, IDE_TFLAG_NO_SELECT_MASK | 1049 IDE_TFLAG_OUT_DEVICE, bcount, dma_ok); 1050 1051 if (dma_ok) 1052 /* Will begin DMA later */ 1053 pc->flags |= PC_FLAG_DMA_IN_PROGRESS; 1054 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags)) { 1055 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc, 1056 IDETAPE_WAIT_CMD, NULL); 1057 return ide_started; 1058 } else { 1059 ide_execute_pkt_cmd(drive); 1060 return idetape_transfer_pc(drive); 1061 } 1062} 1063 1064static ide_startstop_t idetape_pc_callback(ide_drive_t *drive) 1065{ 1066 idetape_tape_t *tape = drive->driver_data; 1067 1068 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1069 1070 idetape_end_request(drive, tape->pc->error ? 0 : 1, 0); 1071 return ide_stopped; 1072} 1073 1074/* A mode sense command is used to "sense" tape parameters. */ 1075static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code) 1076{ 1077 idetape_init_pc(pc); 1078 pc->c[0] = MODE_SENSE; 1079 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 1080 /* DBD = 1 - Don't return block descriptors */ 1081 pc->c[1] = 8; 1082 pc->c[2] = page_code; 1083 /* 1084 * Changed pc->c[3] to 0 (255 will at best return unused info). 1085 * 1086 * For SCSI this byte is defined as subpage instead of high byte 1087 * of length and some IDE drives seem to interpret it this way 1088 * and return an error when 255 is used. 1089 */ 1090 pc->c[3] = 0; 1091 /* We will just discard data in that case */ 1092 pc->c[4] = 255; 1093 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 1094 pc->req_xfer = 12; 1095 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 1096 pc->req_xfer = 24; 1097 else 1098 pc->req_xfer = 50; 1099 pc->idetape_callback = &idetape_pc_callback; 1100} 1101 1102static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive) 1103{ 1104 idetape_tape_t *tape = drive->driver_data; 1105 struct ide_atapi_pc *pc = tape->pc; 1106 u8 stat; 1107 1108 stat = ide_read_status(drive); 1109 1110 if (stat & SEEK_STAT) { 1111 if (stat & ERR_STAT) { 1112 /* Error detected */ 1113 if (pc->c[0] != TEST_UNIT_READY) 1114 printk(KERN_ERR "ide-tape: %s: I/O error, ", 1115 tape->name); 1116 /* Retry operation */ 1117 return idetape_retry_pc(drive); 1118 } 1119 pc->error = 0; 1120 if (tape->failed_pc == pc) 1121 tape->failed_pc = NULL; 1122 } else { 1123 pc->error = IDETAPE_ERROR_GENERAL; 1124 tape->failed_pc = NULL; 1125 } 1126 return pc->idetape_callback(drive); 1127} 1128 1129static ide_startstop_t idetape_rw_callback(ide_drive_t *drive) 1130{ 1131 idetape_tape_t *tape = drive->driver_data; 1132 struct request *rq = HWGROUP(drive)->rq; 1133 int blocks = tape->pc->xferred / tape->blk_size; 1134 1135 tape->avg_size += blocks * tape->blk_size; 1136 1137 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 1138 tape->avg_speed = tape->avg_size * HZ / 1139 (jiffies - tape->avg_time) / 1024; 1140 tape->avg_size = 0; 1141 tape->avg_time = jiffies; 1142 } 1143 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1144 1145 tape->first_frame += blocks; 1146 rq->current_nr_sectors -= blocks; 1147 1148 if (!tape->pc->error) 1149 idetape_end_request(drive, 1, 0); 1150 else 1151 idetape_end_request(drive, tape->pc->error, 0); 1152 return ide_stopped; 1153} 1154 1155static void idetape_create_read_cmd(idetape_tape_t *tape, 1156 struct ide_atapi_pc *pc, 1157 unsigned int length, struct idetape_bh *bh) 1158{ 1159 idetape_init_pc(pc); 1160 pc->c[0] = READ_6; 1161 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1162 pc->c[1] = 1; 1163 pc->idetape_callback = &idetape_rw_callback; 1164 pc->bh = bh; 1165 atomic_set(&bh->b_count, 0); 1166 pc->buf = NULL; 1167 pc->buf_size = length * tape->blk_size; 1168 pc->req_xfer = pc->buf_size; 1169 if (pc->req_xfer == tape->buffer_size) 1170 pc->flags |= PC_FLAG_DMA_RECOMMENDED; 1171} 1172 1173static void idetape_create_write_cmd(idetape_tape_t *tape, 1174 struct ide_atapi_pc *pc, 1175 unsigned int length, struct idetape_bh *bh) 1176{ 1177 idetape_init_pc(pc); 1178 pc->c[0] = WRITE_6; 1179 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1180 pc->c[1] = 1; 1181 pc->idetape_callback = &idetape_rw_callback; 1182 pc->flags |= PC_FLAG_WRITING; 1183 pc->bh = bh; 1184 pc->b_data = bh->b_data; 1185 pc->b_count = atomic_read(&bh->b_count); 1186 pc->buf = NULL; 1187 pc->buf_size = length * tape->blk_size; 1188 pc->req_xfer = pc->buf_size; 1189 if (pc->req_xfer == tape->buffer_size) 1190 pc->flags |= PC_FLAG_DMA_RECOMMENDED; 1191} 1192 1193static ide_startstop_t idetape_do_request(ide_drive_t *drive, 1194 struct request *rq, sector_t block) 1195{ 1196 idetape_tape_t *tape = drive->driver_data; 1197 struct ide_atapi_pc *pc = NULL; 1198 struct request *postponed_rq = tape->postponed_rq; 1199 u8 stat; 1200 1201 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld," 1202 " current_nr_sectors: %d\n", 1203 rq->sector, rq->nr_sectors, rq->current_nr_sectors); 1204 1205 if (!blk_special_request(rq)) { 1206 /* We do not support buffer cache originated requests. */ 1207 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 1208 "request queue (%d)\n", drive->name, rq->cmd_type); 1209 ide_end_request(drive, 0, 0); 1210 return ide_stopped; 1211 } 1212 1213 /* Retry a failed packet command */ 1214 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE) 1215 return idetape_issue_pc(drive, tape->failed_pc); 1216 1217 if (postponed_rq != NULL) 1218 if (rq != postponed_rq) { 1219 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 1220 "Two DSC requests were queued\n"); 1221 idetape_end_request(drive, 0, 0); 1222 return ide_stopped; 1223 } 1224 1225 tape->postponed_rq = NULL; 1226 1227 /* 1228 * If the tape is still busy, postpone our request and service 1229 * the other device meanwhile. 1230 */ 1231 stat = ide_read_status(drive); 1232 1233 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2)) 1234 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1235 1236 if (drive->post_reset == 1) { 1237 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags); 1238 drive->post_reset = 0; 1239 } 1240 1241 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) && 1242 (stat & SEEK_STAT) == 0) { 1243 if (postponed_rq == NULL) { 1244 tape->dsc_polling_start = jiffies; 1245 tape->dsc_poll_freq = tape->best_dsc_rw_freq; 1246 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 1247 } else if (time_after(jiffies, tape->dsc_timeout)) { 1248 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 1249 tape->name); 1250 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1251 idetape_media_access_finished(drive); 1252 return ide_stopped; 1253 } else { 1254 return ide_do_reset(drive); 1255 } 1256 } else if (time_after(jiffies, 1257 tape->dsc_polling_start + 1258 IDETAPE_DSC_MA_THRESHOLD)) 1259 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW; 1260 idetape_postpone_request(drive); 1261 return ide_stopped; 1262 } 1263 if (rq->cmd[0] & REQ_IDETAPE_READ) { 1264 pc = idetape_next_pc_storage(drive); 1265 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, 1266 (struct idetape_bh *)rq->special); 1267 goto out; 1268 } 1269 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 1270 pc = idetape_next_pc_storage(drive); 1271 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, 1272 (struct idetape_bh *)rq->special); 1273 goto out; 1274 } 1275 if (rq->cmd[0] & REQ_IDETAPE_PC1) { 1276 pc = (struct ide_atapi_pc *) rq->buffer; 1277 rq->cmd[0] &= ~(REQ_IDETAPE_PC1); 1278 rq->cmd[0] |= REQ_IDETAPE_PC2; 1279 goto out; 1280 } 1281 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1282 idetape_media_access_finished(drive); 1283 return ide_stopped; 1284 } 1285 BUG(); 1286out: 1287 return idetape_issue_pc(drive, pc); 1288} 1289 1290/* 1291 * The function below uses __get_free_pages to allocate a data buffer of size 1292 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as 1293 * much as possible. 1294 * 1295 * It returns a pointer to the newly allocated buffer, or NULL in case of 1296 * failure. 1297 */ 1298static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape, 1299 int full, int clear) 1300{ 1301 struct idetape_bh *prev_bh, *bh, *merge_bh; 1302 int pages = tape->pages_per_buffer; 1303 unsigned int order, b_allocd; 1304 char *b_data = NULL; 1305 1306 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1307 bh = merge_bh; 1308 if (bh == NULL) 1309 goto abort; 1310 1311 order = fls(pages) - 1; 1312 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1313 if (!bh->b_data) 1314 goto abort; 1315 b_allocd = (1 << order) * PAGE_SIZE; 1316 pages &= (order-1); 1317 1318 if (clear) 1319 memset(bh->b_data, 0, b_allocd); 1320 bh->b_reqnext = NULL; 1321 bh->b_size = b_allocd; 1322 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1323 1324 while (pages) { 1325 order = fls(pages) - 1; 1326 b_data = (char *) __get_free_pages(GFP_KERNEL, order); 1327 if (!b_data) 1328 goto abort; 1329 b_allocd = (1 << order) * PAGE_SIZE; 1330 1331 if (clear) 1332 memset(b_data, 0, b_allocd); 1333 1334 /* newly allocated page frames below buffer header or ...*/ 1335 if (bh->b_data == b_data + b_allocd) { 1336 bh->b_size += b_allocd; 1337 bh->b_data -= b_allocd; 1338 if (full) 1339 atomic_add(b_allocd, &bh->b_count); 1340 continue; 1341 } 1342 /* they are above the header */ 1343 if (b_data == bh->b_data + bh->b_size) { 1344 bh->b_size += b_allocd; 1345 if (full) 1346 atomic_add(b_allocd, &bh->b_count); 1347 continue; 1348 } 1349 prev_bh = bh; 1350 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1351 if (!bh) { 1352 free_pages((unsigned long) b_data, order); 1353 goto abort; 1354 } 1355 bh->b_reqnext = NULL; 1356 bh->b_data = b_data; 1357 bh->b_size = b_allocd; 1358 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1359 prev_bh->b_reqnext = bh; 1360 1361 pages &= (order-1); 1362 } 1363 1364 bh->b_size -= tape->excess_bh_size; 1365 if (full) 1366 atomic_sub(tape->excess_bh_size, &bh->b_count); 1367 return merge_bh; 1368abort: 1369 ide_tape_kfree_buffer(tape); 1370 return NULL; 1371} 1372 1373static int idetape_copy_stage_from_user(idetape_tape_t *tape, 1374 const char __user *buf, int n) 1375{ 1376 struct idetape_bh *bh = tape->bh; 1377 int count; 1378 int ret = 0; 1379 1380 while (n) { 1381 if (bh == NULL) { 1382 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1383 __func__); 1384 return 1; 1385 } 1386 count = min((unsigned int) 1387 (bh->b_size - atomic_read(&bh->b_count)), 1388 (unsigned int)n); 1389 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, 1390 count)) 1391 ret = 1; 1392 n -= count; 1393 atomic_add(count, &bh->b_count); 1394 buf += count; 1395 if (atomic_read(&bh->b_count) == bh->b_size) { 1396 bh = bh->b_reqnext; 1397 if (bh) 1398 atomic_set(&bh->b_count, 0); 1399 } 1400 } 1401 tape->bh = bh; 1402 return ret; 1403} 1404 1405static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf, 1406 int n) 1407{ 1408 struct idetape_bh *bh = tape->bh; 1409 int count; 1410 int ret = 0; 1411 1412 while (n) { 1413 if (bh == NULL) { 1414 printk(KERN_ERR "ide-tape: bh == NULL in %s\n", 1415 __func__); 1416 return 1; 1417 } 1418 count = min(tape->b_count, n); 1419 if (copy_to_user(buf, tape->b_data, count)) 1420 ret = 1; 1421 n -= count; 1422 tape->b_data += count; 1423 tape->b_count -= count; 1424 buf += count; 1425 if (!tape->b_count) { 1426 bh = bh->b_reqnext; 1427 tape->bh = bh; 1428 if (bh) { 1429 tape->b_data = bh->b_data; 1430 tape->b_count = atomic_read(&bh->b_count); 1431 } 1432 } 1433 } 1434 return ret; 1435} 1436 1437static void idetape_init_merge_buffer(idetape_tape_t *tape) 1438{ 1439 struct idetape_bh *bh = tape->merge_bh; 1440 tape->bh = tape->merge_bh; 1441 1442 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 1443 atomic_set(&bh->b_count, 0); 1444 else { 1445 tape->b_data = bh->b_data; 1446 tape->b_count = atomic_read(&bh->b_count); 1447 } 1448} 1449 1450static ide_startstop_t idetape_read_position_callback(ide_drive_t *drive) 1451{ 1452 idetape_tape_t *tape = drive->driver_data; 1453 u8 *readpos = tape->pc->buf; 1454 1455 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1456 1457 if (!tape->pc->error) { 1458 debug_log(DBG_SENSE, "BOP - %s\n", 1459 (readpos[0] & 0x80) ? "Yes" : "No"); 1460 debug_log(DBG_SENSE, "EOP - %s\n", 1461 (readpos[0] & 0x40) ? "Yes" : "No"); 1462 1463 if (readpos[0] & 0x4) { 1464 printk(KERN_INFO "ide-tape: Block location is unknown" 1465 "to the tape\n"); 1466 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags); 1467 idetape_end_request(drive, 0, 0); 1468 } else { 1469 debug_log(DBG_SENSE, "Block Location - %u\n", 1470 be32_to_cpu(*(u32 *)&readpos[4])); 1471 1472 tape->partition = readpos[1]; 1473 tape->first_frame = 1474 be32_to_cpu(*(u32 *)&readpos[4]); 1475 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags); 1476 idetape_end_request(drive, 1, 0); 1477 } 1478 } else { 1479 idetape_end_request(drive, 0, 0); 1480 } 1481 return ide_stopped; 1482} 1483 1484/* 1485 * Write a filemark if write_filemark=1. Flush the device buffers without 1486 * writing a filemark otherwise. 1487 */ 1488static void idetape_create_write_filemark_cmd(ide_drive_t *drive, 1489 struct ide_atapi_pc *pc, int write_filemark) 1490{ 1491 idetape_init_pc(pc); 1492 pc->c[0] = WRITE_FILEMARKS; 1493 pc->c[4] = write_filemark; 1494 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1495 pc->idetape_callback = &idetape_pc_callback; 1496} 1497 1498static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc) 1499{ 1500 idetape_init_pc(pc); 1501 pc->c[0] = TEST_UNIT_READY; 1502 pc->idetape_callback = &idetape_pc_callback; 1503} 1504 1505/* 1506 * We add a special packet command request to the tail of the request queue, and 1507 * wait for it to be serviced. This is not to be called from within the request 1508 * handling part of the driver! We allocate here data on the stack and it is 1509 * valid until the request is finished. This is not the case for the bottom part 1510 * of the driver, where we are always leaving the functions to wait for an 1511 * interrupt or a timer event. 1512 * 1513 * From the bottom part of the driver, we should allocate safe memory using 1514 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request 1515 * to the request list without waiting for it to be serviced! In that case, we 1516 * usually use idetape_queue_pc_head(). 1517 */ 1518static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc) 1519{ 1520 struct ide_tape_obj *tape = drive->driver_data; 1521 struct request rq; 1522 1523 idetape_init_rq(&rq, REQ_IDETAPE_PC1); 1524 rq.buffer = (char *) pc; 1525 rq.rq_disk = tape->disk; 1526 return ide_do_drive_cmd(drive, &rq, ide_wait); 1527} 1528 1529static void idetape_create_load_unload_cmd(ide_drive_t *drive, 1530 struct ide_atapi_pc *pc, int cmd) 1531{ 1532 idetape_init_pc(pc); 1533 pc->c[0] = START_STOP; 1534 pc->c[4] = cmd; 1535 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1536 pc->idetape_callback = &idetape_pc_callback; 1537} 1538 1539static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 1540{ 1541 idetape_tape_t *tape = drive->driver_data; 1542 struct ide_atapi_pc pc; 1543 int load_attempted = 0; 1544 1545 /* Wait for the tape to become ready */ 1546 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 1547 timeout += jiffies; 1548 while (time_before(jiffies, timeout)) { 1549 idetape_create_test_unit_ready_cmd(&pc); 1550 if (!idetape_queue_pc_tail(drive, &pc)) 1551 return 0; 1552 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 1553 || (tape->asc == 0x3A)) { 1554 /* no media */ 1555 if (load_attempted) 1556 return -ENOMEDIUM; 1557 idetape_create_load_unload_cmd(drive, &pc, 1558 IDETAPE_LU_LOAD_MASK); 1559 idetape_queue_pc_tail(drive, &pc); 1560 load_attempted = 1; 1561 /* not about to be ready */ 1562 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 1563 (tape->ascq == 1 || tape->ascq == 8))) 1564 return -EIO; 1565 msleep(100); 1566 } 1567 return -EIO; 1568} 1569 1570static int idetape_flush_tape_buffers(ide_drive_t *drive) 1571{ 1572 struct ide_atapi_pc pc; 1573 int rc; 1574 1575 idetape_create_write_filemark_cmd(drive, &pc, 0); 1576 rc = idetape_queue_pc_tail(drive, &pc); 1577 if (rc) 1578 return rc; 1579 idetape_wait_ready(drive, 60 * 5 * HZ); 1580 return 0; 1581} 1582 1583static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc) 1584{ 1585 idetape_init_pc(pc); 1586 pc->c[0] = READ_POSITION; 1587 pc->req_xfer = 20; 1588 pc->idetape_callback = &idetape_read_position_callback; 1589} 1590 1591static int idetape_read_position(ide_drive_t *drive) 1592{ 1593 idetape_tape_t *tape = drive->driver_data; 1594 struct ide_atapi_pc pc; 1595 int position; 1596 1597 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1598 1599 idetape_create_read_position_cmd(&pc); 1600 if (idetape_queue_pc_tail(drive, &pc)) 1601 return -1; 1602 position = tape->first_frame; 1603 return position; 1604} 1605 1606static void idetape_create_locate_cmd(ide_drive_t *drive, 1607 struct ide_atapi_pc *pc, 1608 unsigned int block, u8 partition, int skip) 1609{ 1610 idetape_init_pc(pc); 1611 pc->c[0] = POSITION_TO_ELEMENT; 1612 pc->c[1] = 2; 1613 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 1614 pc->c[8] = partition; 1615 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1616 pc->idetape_callback = &idetape_pc_callback; 1617} 1618 1619static int idetape_create_prevent_cmd(ide_drive_t *drive, 1620 struct ide_atapi_pc *pc, int prevent) 1621{ 1622 idetape_tape_t *tape = drive->driver_data; 1623 1624 /* device supports locking according to capabilities page */ 1625 if (!(tape->caps[6] & 0x01)) 1626 return 0; 1627 1628 idetape_init_pc(pc); 1629 pc->c[0] = ALLOW_MEDIUM_REMOVAL; 1630 pc->c[4] = prevent; 1631 pc->idetape_callback = &idetape_pc_callback; 1632 return 1; 1633} 1634 1635static void __ide_tape_discard_merge_buffer(ide_drive_t *drive) 1636{ 1637 idetape_tape_t *tape = drive->driver_data; 1638 1639 if (tape->chrdev_dir != IDETAPE_DIR_READ) 1640 return; 1641 1642 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags); 1643 tape->merge_bh_size = 0; 1644 if (tape->merge_bh != NULL) { 1645 ide_tape_kfree_buffer(tape); 1646 tape->merge_bh = NULL; 1647 } 1648 1649 tape->chrdev_dir = IDETAPE_DIR_NONE; 1650} 1651 1652/* 1653 * Position the tape to the requested block using the LOCATE packet command. 1654 * A READ POSITION command is then issued to check where we are positioned. Like 1655 * all higher level operations, we queue the commands at the tail of the request 1656 * queue and wait for their completion. 1657 */ 1658static int idetape_position_tape(ide_drive_t *drive, unsigned int block, 1659 u8 partition, int skip) 1660{ 1661 idetape_tape_t *tape = drive->driver_data; 1662 int retval; 1663 struct ide_atapi_pc pc; 1664 1665 if (tape->chrdev_dir == IDETAPE_DIR_READ) 1666 __ide_tape_discard_merge_buffer(drive); 1667 idetape_wait_ready(drive, 60 * 5 * HZ); 1668 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 1669 retval = idetape_queue_pc_tail(drive, &pc); 1670 if (retval) 1671 return (retval); 1672 1673 idetape_create_read_position_cmd(&pc); 1674 return (idetape_queue_pc_tail(drive, &pc)); 1675} 1676 1677static void ide_tape_discard_merge_buffer(ide_drive_t *drive, 1678 int restore_position) 1679{ 1680 idetape_tape_t *tape = drive->driver_data; 1681 int seek, position; 1682 1683 __ide_tape_discard_merge_buffer(drive); 1684 if (restore_position) { 1685 position = idetape_read_position(drive); 1686 seek = position > 0 ? position : 0; 1687 if (idetape_position_tape(drive, seek, 0, 0)) { 1688 printk(KERN_INFO "ide-tape: %s: position_tape failed in" 1689 " %s\n", tape->name, __func__); 1690 return; 1691 } 1692 } 1693} 1694 1695/* 1696 * Generate a read/write request for the block device interface and wait for it 1697 * to be serviced. 1698 */ 1699static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, 1700 struct idetape_bh *bh) 1701{ 1702 idetape_tape_t *tape = drive->driver_data; 1703 struct request rq; 1704 1705 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 1706 1707 idetape_init_rq(&rq, cmd); 1708 rq.rq_disk = tape->disk; 1709 rq.special = (void *)bh; 1710 rq.sector = tape->first_frame; 1711 rq.nr_sectors = blocks; 1712 rq.current_nr_sectors = blocks; 1713 (void) ide_do_drive_cmd(drive, &rq, ide_wait); 1714 1715 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 1716 return 0; 1717 1718 if (tape->merge_bh) 1719 idetape_init_merge_buffer(tape); 1720 if (rq.errors == IDETAPE_ERROR_GENERAL) 1721 return -EIO; 1722 return (tape->blk_size * (blocks-rq.current_nr_sectors)); 1723} 1724 1725static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc) 1726{ 1727 idetape_init_pc(pc); 1728 pc->c[0] = INQUIRY; 1729 pc->c[4] = 254; 1730 pc->req_xfer = 254; 1731 pc->idetape_callback = &idetape_pc_callback; 1732} 1733 1734static void idetape_create_rewind_cmd(ide_drive_t *drive, 1735 struct ide_atapi_pc *pc) 1736{ 1737 idetape_init_pc(pc); 1738 pc->c[0] = REZERO_UNIT; 1739 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1740 pc->idetape_callback = &idetape_pc_callback; 1741} 1742 1743static void idetape_create_erase_cmd(struct ide_atapi_pc *pc) 1744{ 1745 idetape_init_pc(pc); 1746 pc->c[0] = ERASE; 1747 pc->c[1] = 1; 1748 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1749 pc->idetape_callback = &idetape_pc_callback; 1750} 1751 1752static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd) 1753{ 1754 idetape_init_pc(pc); 1755 pc->c[0] = SPACE; 1756 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 1757 pc->c[1] = cmd; 1758 pc->flags |= PC_FLAG_WAIT_FOR_DSC; 1759 pc->idetape_callback = &idetape_pc_callback; 1760} 1761 1762/* Queue up a character device originated write request. */ 1763static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks) 1764{ 1765 idetape_tape_t *tape = drive->driver_data; 1766 1767 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 1768 1769 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 1770 blocks, tape->merge_bh); 1771} 1772 1773static void ide_tape_flush_merge_buffer(ide_drive_t *drive) 1774{ 1775 idetape_tape_t *tape = drive->driver_data; 1776 int blocks, min; 1777 struct idetape_bh *bh; 1778 1779 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 1780 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer" 1781 " but we are not writing.\n"); 1782 return; 1783 } 1784 if (tape->merge_bh_size > tape->buffer_size) { 1785 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 1786 tape->merge_bh_size = tape->buffer_size; 1787 } 1788 if (tape->merge_bh_size) { 1789 blocks = tape->merge_bh_size / tape->blk_size; 1790 if (tape->merge_bh_size % tape->blk_size) { 1791 unsigned int i; 1792 1793 blocks++; 1794 i = tape->blk_size - tape->merge_bh_size % 1795 tape->blk_size; 1796 bh = tape->bh->b_reqnext; 1797 while (bh) { 1798 atomic_set(&bh->b_count, 0); 1799 bh = bh->b_reqnext; 1800 } 1801 bh = tape->bh; 1802 while (i) { 1803 if (bh == NULL) { 1804 printk(KERN_INFO "ide-tape: bug," 1805 " bh NULL\n"); 1806 break; 1807 } 1808 min = min(i, (unsigned int)(bh->b_size - 1809 atomic_read(&bh->b_count))); 1810 memset(bh->b_data + atomic_read(&bh->b_count), 1811 0, min); 1812 atomic_add(min, &bh->b_count); 1813 i -= min; 1814 bh = bh->b_reqnext; 1815 } 1816 } 1817 (void) idetape_add_chrdev_write_request(drive, blocks); 1818 tape->merge_bh_size = 0; 1819 } 1820 if (tape->merge_bh != NULL) { 1821 ide_tape_kfree_buffer(tape); 1822 tape->merge_bh = NULL; 1823 } 1824 tape->chrdev_dir = IDETAPE_DIR_NONE; 1825} 1826 1827static int idetape_init_read(ide_drive_t *drive) 1828{ 1829 idetape_tape_t *tape = drive->driver_data; 1830 int bytes_read; 1831 1832 /* Initialize read operation */ 1833 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 1834 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 1835 ide_tape_flush_merge_buffer(drive); 1836 idetape_flush_tape_buffers(drive); 1837 } 1838 if (tape->merge_bh || tape->merge_bh_size) { 1839 printk(KERN_ERR "ide-tape: merge_bh_size should be" 1840 " 0 now\n"); 1841 tape->merge_bh_size = 0; 1842 } 1843 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 1844 if (!tape->merge_bh) 1845 return -ENOMEM; 1846 tape->chrdev_dir = IDETAPE_DIR_READ; 1847 1848 /* 1849 * Issue a read 0 command to ensure that DSC handshake is 1850 * switched from completion mode to buffer available mode. 1851 * No point in issuing this if DSC overlap isn't supported, some 1852 * drives (Seagate STT3401A) will return an error. 1853 */ 1854 if (drive->dsc_overlap) { 1855 bytes_read = idetape_queue_rw_tail(drive, 1856 REQ_IDETAPE_READ, 0, 1857 tape->merge_bh); 1858 if (bytes_read < 0) { 1859 ide_tape_kfree_buffer(tape); 1860 tape->merge_bh = NULL; 1861 tape->chrdev_dir = IDETAPE_DIR_NONE; 1862 return bytes_read; 1863 } 1864 } 1865 } 1866 1867 return 0; 1868} 1869 1870/* called from idetape_chrdev_read() to service a chrdev read request. */ 1871static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks) 1872{ 1873 idetape_tape_t *tape = drive->driver_data; 1874 1875 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 1876 1877 /* If we are at a filemark, return a read length of 0 */ 1878 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1879 return 0; 1880 1881 idetape_init_read(drive); 1882 1883 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, 1884 tape->merge_bh); 1885} 1886 1887static void idetape_pad_zeros(ide_drive_t *drive, int bcount) 1888{ 1889 idetape_tape_t *tape = drive->driver_data; 1890 struct idetape_bh *bh; 1891 int blocks; 1892 1893 while (bcount) { 1894 unsigned int count; 1895 1896 bh = tape->merge_bh; 1897 count = min(tape->buffer_size, bcount); 1898 bcount -= count; 1899 blocks = count / tape->blk_size; 1900 while (count) { 1901 atomic_set(&bh->b_count, 1902 min(count, (unsigned int)bh->b_size)); 1903 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 1904 count -= atomic_read(&bh->b_count); 1905 bh = bh->b_reqnext; 1906 } 1907 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, 1908 tape->merge_bh); 1909 } 1910} 1911 1912/* 1913 * Rewinds the tape to the Beginning Of the current Partition (BOP). We 1914 * currently support only one partition. 1915 */ 1916static int idetape_rewind_tape(ide_drive_t *drive) 1917{ 1918 int retval; 1919 struct ide_atapi_pc pc; 1920 idetape_tape_t *tape; 1921 tape = drive->driver_data; 1922 1923 debug_log(DBG_SENSE, "Enter %s\n", __func__); 1924 1925 idetape_create_rewind_cmd(drive, &pc); 1926 retval = idetape_queue_pc_tail(drive, &pc); 1927 if (retval) 1928 return retval; 1929 1930 idetape_create_read_position_cmd(&pc); 1931 retval = idetape_queue_pc_tail(drive, &pc); 1932 if (retval) 1933 return retval; 1934 return 0; 1935} 1936 1937/* mtio.h compatible commands should be issued to the chrdev interface. */ 1938static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, 1939 unsigned long arg) 1940{ 1941 idetape_tape_t *tape = drive->driver_data; 1942 void __user *argp = (void __user *)arg; 1943 1944 struct idetape_config { 1945 int dsc_rw_frequency; 1946 int dsc_media_access_frequency; 1947 int nr_stages; 1948 } config; 1949 1950 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1951 1952 switch (cmd) { 1953 case 0x0340: 1954 if (copy_from_user(&config, argp, sizeof(config))) 1955 return -EFAULT; 1956 tape->best_dsc_rw_freq = config.dsc_rw_frequency; 1957 break; 1958 case 0x0350: 1959 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq; 1960 config.nr_stages = 1; 1961 if (copy_to_user(argp, &config, sizeof(config))) 1962 return -EFAULT; 1963 break; 1964 default: 1965 return -EIO; 1966 } 1967 return 0; 1968} 1969 1970static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op, 1971 int mt_count) 1972{ 1973 idetape_tape_t *tape = drive->driver_data; 1974 struct ide_atapi_pc pc; 1975 int retval, count = 0; 1976 int sprev = !!(tape->caps[4] & 0x20); 1977 1978 if (mt_count == 0) 1979 return 0; 1980 if (MTBSF == mt_op || MTBSFM == mt_op) { 1981 if (!sprev) 1982 return -EIO; 1983 mt_count = -mt_count; 1984 } 1985 1986 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 1987 tape->merge_bh_size = 0; 1988 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) 1989 ++count; 1990 ide_tape_discard_merge_buffer(drive, 0); 1991 } 1992 1993 switch (mt_op) { 1994 case MTFSF: 1995 case MTBSF: 1996 idetape_create_space_cmd(&pc, mt_count - count, 1997 IDETAPE_SPACE_OVER_FILEMARK); 1998 return idetape_queue_pc_tail(drive, &pc); 1999 case MTFSFM: 2000 case MTBSFM: 2001 if (!sprev) 2002 return -EIO; 2003 retval = idetape_space_over_filemarks(drive, MTFSF, 2004 mt_count - count); 2005 if (retval) 2006 return retval; 2007 count = (MTBSFM == mt_op ? 1 : -1); 2008 return idetape_space_over_filemarks(drive, MTFSF, count); 2009 default: 2010 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 2011 mt_op); 2012 return -EIO; 2013 } 2014} 2015 2016/* 2017 * Our character device read / write functions. 2018 * 2019 * The tape is optimized to maximize throughput when it is transferring an 2020 * integral number of the "continuous transfer limit", which is a parameter of 2021 * the specific tape (26kB on my particular tape, 32kB for Onstream). 2022 * 2023 * As of version 1.3 of the driver, the character device provides an abstract 2024 * continuous view of the media - any mix of block sizes (even 1 byte) on the 2025 * same backup/restore procedure is supported. The driver will internally 2026 * convert the requests to the recommended transfer unit, so that an unmatch 2027 * between the user's block size to the recommended size will only result in a 2028 * (slightly) increased driver overhead, but will no longer hit performance. 2029 * This is not applicable to Onstream. 2030 */ 2031static ssize_t idetape_chrdev_read(struct file *file, char __user *buf, 2032 size_t count, loff_t *ppos) 2033{ 2034 struct ide_tape_obj *tape = ide_tape_f(file); 2035 ide_drive_t *drive = tape->drive; 2036 ssize_t bytes_read, temp, actually_read = 0, rc; 2037 ssize_t ret = 0; 2038 u16 ctl = *(u16 *)&tape->caps[12]; 2039 2040 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 2041 2042 if (tape->chrdev_dir != IDETAPE_DIR_READ) { 2043 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags)) 2044 if (count > tape->blk_size && 2045 (count % tape->blk_size) == 0) 2046 tape->user_bs_factor = count / tape->blk_size; 2047 } 2048 rc = idetape_init_read(drive); 2049 if (rc < 0) 2050 return rc; 2051 if (count == 0) 2052 return (0); 2053 if (tape->merge_bh_size) { 2054 actually_read = min((unsigned int)(tape->merge_bh_size), 2055 (unsigned int)count); 2056 if (idetape_copy_stage_to_user(tape, buf, actually_read)) 2057 ret = -EFAULT; 2058 buf += actually_read; 2059 tape->merge_bh_size -= actually_read; 2060 count -= actually_read; 2061 } 2062 while (count >= tape->buffer_size) { 2063 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2064 if (bytes_read <= 0) 2065 goto finish; 2066 if (idetape_copy_stage_to_user(tape, buf, bytes_read)) 2067 ret = -EFAULT; 2068 buf += bytes_read; 2069 count -= bytes_read; 2070 actually_read += bytes_read; 2071 } 2072 if (count) { 2073 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2074 if (bytes_read <= 0) 2075 goto finish; 2076 temp = min((unsigned long)count, (unsigned long)bytes_read); 2077 if (idetape_copy_stage_to_user(tape, buf, temp)) 2078 ret = -EFAULT; 2079 actually_read += temp; 2080 tape->merge_bh_size = bytes_read-temp; 2081 } 2082finish: 2083 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) { 2084 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 2085 2086 idetape_space_over_filemarks(drive, MTFSF, 1); 2087 return 0; 2088 } 2089 2090 return ret ? ret : actually_read; 2091} 2092 2093static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf, 2094 size_t count, loff_t *ppos) 2095{ 2096 struct ide_tape_obj *tape = ide_tape_f(file); 2097 ide_drive_t *drive = tape->drive; 2098 ssize_t actually_written = 0; 2099 ssize_t ret = 0; 2100 u16 ctl = *(u16 *)&tape->caps[12]; 2101 2102 /* The drive is write protected. */ 2103 if (tape->write_prot) 2104 return -EACCES; 2105 2106 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 2107 2108 /* Initialize write operation */ 2109 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) { 2110 if (tape->chrdev_dir == IDETAPE_DIR_READ) 2111 ide_tape_discard_merge_buffer(drive, 1); 2112 if (tape->merge_bh || tape->merge_bh_size) { 2113 printk(KERN_ERR "ide-tape: merge_bh_size " 2114 "should be 0 now\n"); 2115 tape->merge_bh_size = 0; 2116 } 2117 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0); 2118 if (!tape->merge_bh) 2119 return -ENOMEM; 2120 tape->chrdev_dir = IDETAPE_DIR_WRITE; 2121 idetape_init_merge_buffer(tape); 2122 2123 /* 2124 * Issue a write 0 command to ensure that DSC handshake is 2125 * switched from completion mode to buffer available mode. No 2126 * point in issuing this if DSC overlap isn't supported, some 2127 * drives (Seagate STT3401A) will return an error. 2128 */ 2129 if (drive->dsc_overlap) { 2130 ssize_t retval = idetape_queue_rw_tail(drive, 2131 REQ_IDETAPE_WRITE, 0, 2132 tape->merge_bh); 2133 if (retval < 0) { 2134 ide_tape_kfree_buffer(tape); 2135 tape->merge_bh = NULL; 2136 tape->chrdev_dir = IDETAPE_DIR_NONE; 2137 return retval; 2138 } 2139 } 2140 } 2141 if (count == 0) 2142 return (0); 2143 if (tape->merge_bh_size) { 2144 if (tape->merge_bh_size >= tape->buffer_size) { 2145 printk(KERN_ERR "ide-tape: bug: merge buf too big\n"); 2146 tape->merge_bh_size = 0; 2147 } 2148 actually_written = min((unsigned int) 2149 (tape->buffer_size - tape->merge_bh_size), 2150 (unsigned int)count); 2151 if (idetape_copy_stage_from_user(tape, buf, actually_written)) 2152 ret = -EFAULT; 2153 buf += actually_written; 2154 tape->merge_bh_size += actually_written; 2155 count -= actually_written; 2156 2157 if (tape->merge_bh_size == tape->buffer_size) { 2158 ssize_t retval; 2159 tape->merge_bh_size = 0; 2160 retval = idetape_add_chrdev_write_request(drive, ctl); 2161 if (retval <= 0) 2162 return (retval); 2163 } 2164 } 2165 while (count >= tape->buffer_size) { 2166 ssize_t retval; 2167 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size)) 2168 ret = -EFAULT; 2169 buf += tape->buffer_size; 2170 count -= tape->buffer_size; 2171 retval = idetape_add_chrdev_write_request(drive, ctl); 2172 actually_written += tape->buffer_size; 2173 if (retval <= 0) 2174 return (retval); 2175 } 2176 if (count) { 2177 actually_written += count; 2178 if (idetape_copy_stage_from_user(tape, buf, count)) 2179 ret = -EFAULT; 2180 tape->merge_bh_size += count; 2181 } 2182 return ret ? ret : actually_written; 2183} 2184 2185static int idetape_write_filemark(ide_drive_t *drive) 2186{ 2187 struct ide_atapi_pc pc; 2188 2189 /* Write a filemark */ 2190 idetape_create_write_filemark_cmd(drive, &pc, 1); 2191 if (idetape_queue_pc_tail(drive, &pc)) { 2192 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 2193 return -EIO; 2194 } 2195 return 0; 2196} 2197 2198/* 2199 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 2200 * requested. 2201 * 2202 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 2203 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 2204 * usually not supported. 2205 * 2206 * The following commands are currently not supported: 2207 * 2208 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 2209 * MT_ST_WRITE_THRESHOLD. 2210 */ 2211static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 2212{ 2213 idetape_tape_t *tape = drive->driver_data; 2214 struct ide_atapi_pc pc; 2215 int i, retval; 2216 2217 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 2218 mt_op, mt_count); 2219 2220 switch (mt_op) { 2221 case MTFSF: 2222 case MTFSFM: 2223 case MTBSF: 2224 case MTBSFM: 2225 if (!mt_count) 2226 return 0; 2227 return idetape_space_over_filemarks(drive, mt_op, mt_count); 2228 default: 2229 break; 2230 } 2231 2232 switch (mt_op) { 2233 case MTWEOF: 2234 if (tape->write_prot) 2235 return -EACCES; 2236 ide_tape_discard_merge_buffer(drive, 1); 2237 for (i = 0; i < mt_count; i++) { 2238 retval = idetape_write_filemark(drive); 2239 if (retval) 2240 return retval; 2241 } 2242 return 0; 2243 case MTREW: 2244 ide_tape_discard_merge_buffer(drive, 0); 2245 if (idetape_rewind_tape(drive)) 2246 return -EIO; 2247 return 0; 2248 case MTLOAD: 2249 ide_tape_discard_merge_buffer(drive, 0); 2250 idetape_create_load_unload_cmd(drive, &pc, 2251 IDETAPE_LU_LOAD_MASK); 2252 return idetape_queue_pc_tail(drive, &pc); 2253 case MTUNLOAD: 2254 case MTOFFL: 2255 /* 2256 * If door is locked, attempt to unlock before 2257 * attempting to eject. 2258 */ 2259 if (tape->door_locked) { 2260 if (idetape_create_prevent_cmd(drive, &pc, 0)) 2261 if (!idetape_queue_pc_tail(drive, &pc)) 2262 tape->door_locked = DOOR_UNLOCKED; 2263 } 2264 ide_tape_discard_merge_buffer(drive, 0); 2265 idetape_create_load_unload_cmd(drive, &pc, 2266 !IDETAPE_LU_LOAD_MASK); 2267 retval = idetape_queue_pc_tail(drive, &pc); 2268 if (!retval) 2269 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags); 2270 return retval; 2271 case MTNOP: 2272 ide_tape_discard_merge_buffer(drive, 0); 2273 return idetape_flush_tape_buffers(drive); 2274 case MTRETEN: 2275 ide_tape_discard_merge_buffer(drive, 0); 2276 idetape_create_load_unload_cmd(drive, &pc, 2277 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 2278 return idetape_queue_pc_tail(drive, &pc); 2279 case MTEOM: 2280 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 2281 return idetape_queue_pc_tail(drive, &pc); 2282 case MTERASE: 2283 (void)idetape_rewind_tape(drive); 2284 idetape_create_erase_cmd(&pc); 2285 return idetape_queue_pc_tail(drive, &pc); 2286 case MTSETBLK: 2287 if (mt_count) { 2288 if (mt_count < tape->blk_size || 2289 mt_count % tape->blk_size) 2290 return -EIO; 2291 tape->user_bs_factor = mt_count / tape->blk_size; 2292 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2293 } else 2294 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags); 2295 return 0; 2296 case MTSEEK: 2297 ide_tape_discard_merge_buffer(drive, 0); 2298 return idetape_position_tape(drive, 2299 mt_count * tape->user_bs_factor, tape->partition, 0); 2300 case MTSETPART: 2301 ide_tape_discard_merge_buffer(drive, 0); 2302 return idetape_position_tape(drive, 0, mt_count, 0); 2303 case MTFSR: 2304 case MTBSR: 2305 case MTLOCK: 2306 if (!idetape_create_prevent_cmd(drive, &pc, 1)) 2307 return 0; 2308 retval = idetape_queue_pc_tail(drive, &pc); 2309 if (retval) 2310 return retval; 2311 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 2312 return 0; 2313 case MTUNLOCK: 2314 if (!idetape_create_prevent_cmd(drive, &pc, 0)) 2315 return 0; 2316 retval = idetape_queue_pc_tail(drive, &pc); 2317 if (retval) 2318 return retval; 2319 tape->door_locked = DOOR_UNLOCKED; 2320 return 0; 2321 default: 2322 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n", 2323 mt_op); 2324 return -EIO; 2325 } 2326} 2327 2328/* 2329 * Our character device ioctls. General mtio.h magnetic io commands are 2330 * supported here, and not in the corresponding block interface. Our own 2331 * ide-tape ioctls are supported on both interfaces. 2332 */ 2333static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 2334 unsigned int cmd, unsigned long arg) 2335{ 2336 struct ide_tape_obj *tape = ide_tape_f(file); 2337 ide_drive_t *drive = tape->drive; 2338 struct mtop mtop; 2339 struct mtget mtget; 2340 struct mtpos mtpos; 2341 int block_offset = 0, position = tape->first_frame; 2342 void __user *argp = (void __user *)arg; 2343 2344 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 2345 2346 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) { 2347 ide_tape_flush_merge_buffer(drive); 2348 idetape_flush_tape_buffers(drive); 2349 } 2350 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 2351 block_offset = tape->merge_bh_size / 2352 (tape->blk_size * tape->user_bs_factor); 2353 position = idetape_read_position(drive); 2354 if (position < 0) 2355 return -EIO; 2356 } 2357 switch (cmd) { 2358 case MTIOCTOP: 2359 if (copy_from_user(&mtop, argp, sizeof(struct mtop))) 2360 return -EFAULT; 2361 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count); 2362 case MTIOCGET: 2363 memset(&mtget, 0, sizeof(struct mtget)); 2364 mtget.mt_type = MT_ISSCSI2; 2365 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 2366 mtget.mt_dsreg = 2367 ((tape->blk_size * tape->user_bs_factor) 2368 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 2369 2370 if (tape->drv_write_prot) 2371 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 2372 2373 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 2374 return -EFAULT; 2375 return 0; 2376 case MTIOCPOS: 2377 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 2378 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 2379 return -EFAULT; 2380 return 0; 2381 default: 2382 if (tape->chrdev_dir == IDETAPE_DIR_READ) 2383 ide_tape_discard_merge_buffer(drive, 1); 2384 return idetape_blkdev_ioctl(drive, cmd, arg); 2385 } 2386} 2387 2388/* 2389 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 2390 * block size with the reported value. 2391 */ 2392static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 2393{ 2394 idetape_tape_t *tape = drive->driver_data; 2395 struct ide_atapi_pc pc; 2396 2397 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 2398 if (idetape_queue_pc_tail(drive, &pc)) { 2399 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 2400 if (tape->blk_size == 0) { 2401 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 2402 "block size, assuming 32k\n"); 2403 tape->blk_size = 32768; 2404 } 2405 return; 2406 } 2407 tape->blk_size = (pc.buf[4 + 5] << 16) + 2408 (pc.buf[4 + 6] << 8) + 2409 pc.buf[4 + 7]; 2410 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7; 2411} 2412 2413static int idetape_chrdev_open(struct inode *inode, struct file *filp) 2414{ 2415 unsigned int minor = iminor(inode), i = minor & ~0xc0; 2416 ide_drive_t *drive; 2417 idetape_tape_t *tape; 2418 struct ide_atapi_pc pc; 2419 int retval; 2420 2421 if (i >= MAX_HWIFS * MAX_DRIVES) 2422 return -ENXIO; 2423 2424 tape = ide_tape_chrdev_get(i); 2425 if (!tape) 2426 return -ENXIO; 2427 2428 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2429 2430 /* 2431 * We really want to do nonseekable_open(inode, filp); here, but some 2432 * versions of tar incorrectly call lseek on tapes and bail out if that 2433 * fails. So we disallow pread() and pwrite(), but permit lseeks. 2434 */ 2435 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 2436 2437 drive = tape->drive; 2438 2439 filp->private_data = tape; 2440 2441 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) { 2442 retval = -EBUSY; 2443 goto out_put_tape; 2444 } 2445 2446 retval = idetape_wait_ready(drive, 60 * HZ); 2447 if (retval) { 2448 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2449 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 2450 goto out_put_tape; 2451 } 2452 2453 idetape_read_position(drive); 2454 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags)) 2455 (void)idetape_rewind_tape(drive); 2456 2457 /* Read block size and write protect status from drive. */ 2458 ide_tape_get_bsize_from_bdesc(drive); 2459 2460 /* Set write protect flag if device is opened as read-only. */ 2461 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 2462 tape->write_prot = 1; 2463 else 2464 tape->write_prot = tape->drv_write_prot; 2465 2466 /* Make sure drive isn't write protected if user wants to write. */ 2467 if (tape->write_prot) { 2468 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 2469 (filp->f_flags & O_ACCMODE) == O_RDWR) { 2470 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2471 retval = -EROFS; 2472 goto out_put_tape; 2473 } 2474 } 2475 2476 /* Lock the tape drive door so user can't eject. */ 2477 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2478 if (idetape_create_prevent_cmd(drive, &pc, 1)) { 2479 if (!idetape_queue_pc_tail(drive, &pc)) { 2480 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 2481 tape->door_locked = DOOR_LOCKED; 2482 } 2483 } 2484 } 2485 return 0; 2486 2487out_put_tape: 2488 ide_tape_put(tape); 2489 return retval; 2490} 2491 2492static void idetape_write_release(ide_drive_t *drive, unsigned int minor) 2493{ 2494 idetape_tape_t *tape = drive->driver_data; 2495 2496 ide_tape_flush_merge_buffer(drive); 2497 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0); 2498 if (tape->merge_bh != NULL) { 2499 idetape_pad_zeros(drive, tape->blk_size * 2500 (tape->user_bs_factor - 1)); 2501 ide_tape_kfree_buffer(tape); 2502 tape->merge_bh = NULL; 2503 } 2504 idetape_write_filemark(drive); 2505 idetape_flush_tape_buffers(drive); 2506 idetape_flush_tape_buffers(drive); 2507} 2508 2509static int idetape_chrdev_release(struct inode *inode, struct file *filp) 2510{ 2511 struct ide_tape_obj *tape = ide_tape_f(filp); 2512 ide_drive_t *drive = tape->drive; 2513 struct ide_atapi_pc pc; 2514 unsigned int minor = iminor(inode); 2515 2516 lock_kernel(); 2517 tape = drive->driver_data; 2518 2519 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2520 2521 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) 2522 idetape_write_release(drive, minor); 2523 if (tape->chrdev_dir == IDETAPE_DIR_READ) { 2524 if (minor < 128) 2525 ide_tape_discard_merge_buffer(drive, 1); 2526 } 2527 2528 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags)) 2529 (void) idetape_rewind_tape(drive); 2530 if (tape->chrdev_dir == IDETAPE_DIR_NONE) { 2531 if (tape->door_locked == DOOR_LOCKED) { 2532 if (idetape_create_prevent_cmd(drive, &pc, 0)) { 2533 if (!idetape_queue_pc_tail(drive, &pc)) 2534 tape->door_locked = DOOR_UNLOCKED; 2535 } 2536 } 2537 } 2538 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags); 2539 ide_tape_put(tape); 2540 unlock_kernel(); 2541 return 0; 2542} 2543 2544/* 2545 * check the contents of the ATAPI IDENTIFY command results. We return: 2546 * 2547 * 1 - If the tape can be supported by us, based on the information we have so 2548 * far. 2549 * 2550 * 0 - If this tape driver is not currently supported by us. 2551 */ 2552static int idetape_identify_device(ide_drive_t *drive) 2553{ 2554 u8 gcw[2], protocol, device_type, removable, packet_size; 2555 2556 if (drive->id_read == 0) 2557 return 1; 2558 2559 *((unsigned short *) &gcw) = drive->id->config; 2560 2561 protocol = (gcw[1] & 0xC0) >> 6; 2562 device_type = gcw[1] & 0x1F; 2563 removable = !!(gcw[0] & 0x80); 2564 packet_size = gcw[0] & 0x3; 2565 2566 /* Check that we can support this device */ 2567 if (protocol != 2) 2568 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n", 2569 protocol); 2570 else if (device_type != 1) 2571 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set " 2572 "to tape\n", device_type); 2573 else if (!removable) 2574 printk(KERN_ERR "ide-tape: The removable flag is not set\n"); 2575 else if (packet_size != 0) { 2576 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12" 2577 " bytes\n", packet_size); 2578 } else 2579 return 1; 2580 return 0; 2581} 2582 2583static void idetape_get_inquiry_results(ide_drive_t *drive) 2584{ 2585 idetape_tape_t *tape = drive->driver_data; 2586 struct ide_atapi_pc pc; 2587 char fw_rev[6], vendor_id[10], product_id[18]; 2588 2589 idetape_create_inquiry_cmd(&pc); 2590 if (idetape_queue_pc_tail(drive, &pc)) { 2591 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 2592 tape->name); 2593 return; 2594 } 2595 memcpy(vendor_id, &pc.buf[8], 8); 2596 memcpy(product_id, &pc.buf[16], 16); 2597 memcpy(fw_rev, &pc.buf[32], 4); 2598 2599 ide_fixstring(vendor_id, 10, 0); 2600 ide_fixstring(product_id, 18, 0); 2601 ide_fixstring(fw_rev, 6, 0); 2602 2603 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n", 2604 drive->name, tape->name, vendor_id, product_id, fw_rev); 2605} 2606 2607/* 2608 * Ask the tape about its various parameters. In particular, we will adjust our 2609 * data transfer buffer size to the recommended value as returned by the tape. 2610 */ 2611static void idetape_get_mode_sense_results(ide_drive_t *drive) 2612{ 2613 idetape_tape_t *tape = drive->driver_data; 2614 struct ide_atapi_pc pc; 2615 u8 *caps; 2616 u8 speed, max_speed; 2617 2618 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 2619 if (idetape_queue_pc_tail(drive, &pc)) { 2620 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 2621 " some default values\n"); 2622 tape->blk_size = 512; 2623 put_unaligned(52, (u16 *)&tape->caps[12]); 2624 put_unaligned(540, (u16 *)&tape->caps[14]); 2625 put_unaligned(6*52, (u16 *)&tape->caps[16]); 2626 return; 2627 } 2628 caps = pc.buf + 4 + pc.buf[3]; 2629 2630 /* convert to host order and save for later use */ 2631 speed = be16_to_cpu(*(u16 *)&caps[14]); 2632 max_speed = be16_to_cpu(*(u16 *)&caps[8]); 2633 2634 put_unaligned(max_speed, (u16 *)&caps[8]); 2635 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]); 2636 put_unaligned(speed, (u16 *)&caps[14]); 2637 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]); 2638 2639 if (!speed) { 2640 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 2641 "(assuming 650KB/sec)\n", drive->name); 2642 put_unaligned(650, (u16 *)&caps[14]); 2643 } 2644 if (!max_speed) { 2645 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 2646 "(assuming 650KB/sec)\n", drive->name); 2647 put_unaligned(650, (u16 *)&caps[8]); 2648 } 2649 2650 memcpy(&tape->caps, caps, 20); 2651 if (caps[7] & 0x02) 2652 tape->blk_size = 512; 2653 else if (caps[7] & 0x04) 2654 tape->blk_size = 1024; 2655} 2656 2657#ifdef CONFIG_IDE_PROC_FS 2658static void idetape_add_settings(ide_drive_t *drive) 2659{ 2660 idetape_tape_t *tape = drive->driver_data; 2661 2662 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2663 1, 2, (u16 *)&tape->caps[16], NULL); 2664 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff, 2665 1, 1, (u16 *)&tape->caps[14], NULL); 2666 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff, 2667 1, 1024, &tape->buffer_size, NULL); 2668 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN, 2669 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq, 2670 NULL); 2671 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1, 2672 1, &drive->dsc_overlap, NULL); 2673 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff, 2674 1, 1, &tape->avg_speed, NULL); 2675 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1, 2676 1, &tape->debug_mask, NULL); 2677} 2678#else 2679static inline void idetape_add_settings(ide_drive_t *drive) { ; } 2680#endif 2681 2682/* 2683 * The function below is called to: 2684 * 2685 * 1. Initialize our various state variables. 2686 * 2. Ask the tape for its capabilities. 2687 * 3. Allocate a buffer which will be used for data transfer. The buffer size 2688 * is chosen based on the recommendation which we received in step 2. 2689 * 2690 * Note that at this point ide.c already assigned us an irq, so that we can 2691 * queue requests here and wait for their completion. 2692 */ 2693static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor) 2694{ 2695 unsigned long t; 2696 int speed; 2697 int buffer_size; 2698 u8 gcw[2]; 2699 u16 *ctl = (u16 *)&tape->caps[12]; 2700 2701 spin_lock_init(&tape->lock); 2702 drive->dsc_overlap = 1; 2703 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 2704 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 2705 tape->name); 2706 drive->dsc_overlap = 0; 2707 } 2708 /* Seagate Travan drives do not support DSC overlap. */ 2709 if (strstr(drive->id->model, "Seagate STT3401")) 2710 drive->dsc_overlap = 0; 2711 tape->minor = minor; 2712 tape->name[0] = 'h'; 2713 tape->name[1] = 't'; 2714 tape->name[2] = '0' + minor; 2715 tape->chrdev_dir = IDETAPE_DIR_NONE; 2716 tape->pc = tape->pc_stack; 2717 *((unsigned short *) &gcw) = drive->id->config; 2718 2719 /* Command packet DRQ type */ 2720 if (((gcw[0] & 0x60) >> 5) == 1) 2721 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags); 2722 2723 idetape_get_inquiry_results(drive); 2724 idetape_get_mode_sense_results(drive); 2725 ide_tape_get_bsize_from_bdesc(drive); 2726 tape->user_bs_factor = 1; 2727 tape->buffer_size = *ctl * tape->blk_size; 2728 while (tape->buffer_size > 0xffff) { 2729 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 2730 *ctl /= 2; 2731 tape->buffer_size = *ctl * tape->blk_size; 2732 } 2733 buffer_size = tape->buffer_size; 2734 tape->pages_per_buffer = buffer_size / PAGE_SIZE; 2735 if (buffer_size % PAGE_SIZE) { 2736 tape->pages_per_buffer++; 2737 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE; 2738 } 2739 2740 /* select the "best" DSC read/write polling freq */ 2741 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 2742 2743 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000); 2744 2745 /* 2746 * Ensure that the number we got makes sense; limit it within 2747 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 2748 */ 2749 tape->best_dsc_rw_freq = max_t(unsigned long, 2750 min_t(unsigned long, t, IDETAPE_DSC_RW_MAX), 2751 IDETAPE_DSC_RW_MIN); 2752 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 2753 "%lums tDSC%s\n", 2754 drive->name, tape->name, *(u16 *)&tape->caps[14], 2755 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size, 2756 tape->buffer_size / 1024, 2757 tape->best_dsc_rw_freq * 1000 / HZ, 2758 drive->using_dma ? ", DMA":""); 2759 2760 idetape_add_settings(drive); 2761} 2762 2763static void ide_tape_remove(ide_drive_t *drive) 2764{ 2765 idetape_tape_t *tape = drive->driver_data; 2766 2767 ide_proc_unregister_driver(drive, tape->driver); 2768 2769 ide_unregister_region(tape->disk); 2770 2771 ide_tape_put(tape); 2772} 2773 2774static void ide_tape_release(struct kref *kref) 2775{ 2776 struct ide_tape_obj *tape = to_ide_tape(kref); 2777 ide_drive_t *drive = tape->drive; 2778 struct gendisk *g = tape->disk; 2779 2780 BUG_ON(tape->merge_bh_size); 2781 2782 drive->dsc_overlap = 0; 2783 drive->driver_data = NULL; 2784 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 2785 device_destroy(idetape_sysfs_class, 2786 MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 2787 idetape_devs[tape->minor] = NULL; 2788 g->private_data = NULL; 2789 put_disk(g); 2790 kfree(tape); 2791} 2792 2793#ifdef CONFIG_IDE_PROC_FS 2794static int proc_idetape_read_name 2795 (char *page, char **start, off_t off, int count, int *eof, void *data) 2796{ 2797 ide_drive_t *drive = (ide_drive_t *) data; 2798 idetape_tape_t *tape = drive->driver_data; 2799 char *out = page; 2800 int len; 2801 2802 len = sprintf(out, "%s\n", tape->name); 2803 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 2804} 2805 2806static ide_proc_entry_t idetape_proc[] = { 2807 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 2808 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 2809 { NULL, 0, NULL, NULL } 2810}; 2811#endif 2812 2813static int ide_tape_probe(ide_drive_t *); 2814 2815static ide_driver_t idetape_driver = { 2816 .gen_driver = { 2817 .owner = THIS_MODULE, 2818 .name = "ide-tape", 2819 .bus = &ide_bus_type, 2820 }, 2821 .probe = ide_tape_probe, 2822 .remove = ide_tape_remove, 2823 .version = IDETAPE_VERSION, 2824 .media = ide_tape, 2825 .supports_dsc_overlap = 1, 2826 .do_request = idetape_do_request, 2827 .end_request = idetape_end_request, 2828 .error = __ide_error, 2829 .abort = __ide_abort, 2830#ifdef CONFIG_IDE_PROC_FS 2831 .proc = idetape_proc, 2832#endif 2833}; 2834 2835/* Our character device supporting functions, passed to register_chrdev. */ 2836static const struct file_operations idetape_fops = { 2837 .owner = THIS_MODULE, 2838 .read = idetape_chrdev_read, 2839 .write = idetape_chrdev_write, 2840 .ioctl = idetape_chrdev_ioctl, 2841 .open = idetape_chrdev_open, 2842 .release = idetape_chrdev_release, 2843}; 2844 2845static int idetape_open(struct inode *inode, struct file *filp) 2846{ 2847 struct gendisk *disk = inode->i_bdev->bd_disk; 2848 struct ide_tape_obj *tape; 2849 2850 tape = ide_tape_get(disk); 2851 if (!tape) 2852 return -ENXIO; 2853 2854 return 0; 2855} 2856 2857static int idetape_release(struct inode *inode, struct file *filp) 2858{ 2859 struct gendisk *disk = inode->i_bdev->bd_disk; 2860 struct ide_tape_obj *tape = ide_tape_g(disk); 2861 2862 ide_tape_put(tape); 2863 2864 return 0; 2865} 2866 2867static int idetape_ioctl(struct inode *inode, struct file *file, 2868 unsigned int cmd, unsigned long arg) 2869{ 2870 struct block_device *bdev = inode->i_bdev; 2871 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 2872 ide_drive_t *drive = tape->drive; 2873 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 2874 if (err == -EINVAL) 2875 err = idetape_blkdev_ioctl(drive, cmd, arg); 2876 return err; 2877} 2878 2879static struct block_device_operations idetape_block_ops = { 2880 .owner = THIS_MODULE, 2881 .open = idetape_open, 2882 .release = idetape_release, 2883 .ioctl = idetape_ioctl, 2884}; 2885 2886static int ide_tape_probe(ide_drive_t *drive) 2887{ 2888 idetape_tape_t *tape; 2889 struct gendisk *g; 2890 int minor; 2891 2892 if (!strstr("ide-tape", drive->driver_req)) 2893 goto failed; 2894 if (!drive->present) 2895 goto failed; 2896 if (drive->media != ide_tape) 2897 goto failed; 2898 if (!idetape_identify_device(drive)) { 2899 printk(KERN_ERR "ide-tape: %s: not supported by this version of" 2900 " the driver\n", drive->name); 2901 goto failed; 2902 } 2903 if (drive->scsi) { 2904 printk(KERN_INFO "ide-tape: passing drive %s to ide-scsi" 2905 " emulation.\n", drive->name); 2906 goto failed; 2907 } 2908 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL); 2909 if (tape == NULL) { 2910 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n", 2911 drive->name); 2912 goto failed; 2913 } 2914 2915 g = alloc_disk(1 << PARTN_BITS); 2916 if (!g) 2917 goto out_free_tape; 2918 2919 ide_init_disk(g, drive); 2920 2921 ide_proc_register_driver(drive, &idetape_driver); 2922 2923 kref_init(&tape->kref); 2924 2925 tape->drive = drive; 2926 tape->driver = &idetape_driver; 2927 tape->disk = g; 2928 2929 g->private_data = &tape->driver; 2930 2931 drive->driver_data = tape; 2932 2933 mutex_lock(&idetape_ref_mutex); 2934 for (minor = 0; idetape_devs[minor]; minor++) 2935 ; 2936 idetape_devs[minor] = tape; 2937 mutex_unlock(&idetape_ref_mutex); 2938 2939 idetape_setup(drive, tape, minor); 2940 2941 device_create(idetape_sysfs_class, &drive->gendev, 2942 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name); 2943 device_create(idetape_sysfs_class, &drive->gendev, 2944 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name); 2945 2946 g->fops = &idetape_block_ops; 2947 ide_register_region(g); 2948 2949 return 0; 2950 2951out_free_tape: 2952 kfree(tape); 2953failed: 2954 return -ENODEV; 2955} 2956 2957static void __exit idetape_exit(void) 2958{ 2959 driver_unregister(&idetape_driver.gen_driver); 2960 class_destroy(idetape_sysfs_class); 2961 unregister_chrdev(IDETAPE_MAJOR, "ht"); 2962} 2963 2964static int __init idetape_init(void) 2965{ 2966 int error = 1; 2967 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 2968 if (IS_ERR(idetape_sysfs_class)) { 2969 idetape_sysfs_class = NULL; 2970 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 2971 error = -EBUSY; 2972 goto out; 2973 } 2974 2975 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 2976 printk(KERN_ERR "ide-tape: Failed to register chrdev" 2977 " interface\n"); 2978 error = -EBUSY; 2979 goto out_free_class; 2980 } 2981 2982 error = driver_register(&idetape_driver.gen_driver); 2983 if (error) 2984 goto out_free_driver; 2985 2986 return 0; 2987 2988out_free_driver: 2989 driver_unregister(&idetape_driver.gen_driver); 2990out_free_class: 2991 class_destroy(idetape_sysfs_class); 2992out: 2993 return error; 2994} 2995 2996MODULE_ALIAS("ide:*m-tape*"); 2997module_init(idetape_init); 2998module_exit(idetape_exit); 2999MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 3000MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 3001MODULE_LICENSE("GPL"); 3002