ide-tape.c revision c47137a99c597330b69057158b26061a360c0e09
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 "1.19" 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 <asm/irq.h> 43#include <asm/uaccess.h> 44#include <asm/io.h> 45#include <asm/unaligned.h> 46#include <linux/mtio.h> 47 48/**************************** Tunable parameters *****************************/ 49 50 51/* 52 * Pipelined mode parameters. 53 * 54 * We try to use the minimum number of stages which is enough to 55 * keep the tape constantly streaming. To accomplish that, we implement 56 * a feedback loop around the maximum number of stages: 57 * 58 * We start from MIN maximum stages (we will not even use MIN stages 59 * if we don't need them), increment it by RATE*(MAX-MIN) 60 * whenever we sense that the pipeline is empty, until we reach 61 * the optimum value or until we reach MAX. 62 * 63 * Setting the following parameter to 0 is illegal: the pipelined mode 64 * cannot be disabled (calculate_speeds() divides by tape->max_stages.) 65 */ 66#define IDETAPE_MIN_PIPELINE_STAGES 1 67#define IDETAPE_MAX_PIPELINE_STAGES 400 68#define IDETAPE_INCREASE_STAGES_RATE 20 69 70/* 71 * The following are used to debug the driver: 72 * 73 * Setting IDETAPE_DEBUG_LOG to 1 will log driver flow control. 74 * 75 * Setting them to 0 will restore normal operation mode: 76 * 77 * 1. Disable logging normal successful operations. 78 * 2. Disable self-sanity checks. 79 * 3. Errors will still be logged, of course. 80 * 81 * All the #if DEBUG code will be removed some day, when the driver 82 * is verified to be stable enough. This will make it much more 83 * esthetic. 84 */ 85#define IDETAPE_DEBUG_LOG 0 86 87/* 88 * After each failed packet command we issue a request sense command 89 * and retry the packet command IDETAPE_MAX_PC_RETRIES times. 90 * 91 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries. 92 */ 93#define IDETAPE_MAX_PC_RETRIES 3 94 95/* 96 * With each packet command, we allocate a buffer of 97 * IDETAPE_PC_BUFFER_SIZE bytes. This is used for several packet 98 * commands (Not for READ/WRITE commands). 99 */ 100#define IDETAPE_PC_BUFFER_SIZE 256 101 102/* 103 * In various places in the driver, we need to allocate storage 104 * for packet commands and requests, which will remain valid while 105 * we leave the driver to wait for an interrupt or a timeout event. 106 */ 107#define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES) 108 109/* 110 * Some drives (for example, Seagate STT3401A Travan) require a very long 111 * timeout, because they don't return an interrupt or clear their busy bit 112 * until after the command completes (even retension commands). 113 */ 114#define IDETAPE_WAIT_CMD (900*HZ) 115 116/* 117 * The following parameter is used to select the point in the internal 118 * tape fifo in which we will start to refill the buffer. Decreasing 119 * the following parameter will improve the system's latency and 120 * interactive response, while using a high value might improve system 121 * throughput. 122 */ 123#define IDETAPE_FIFO_THRESHOLD 2 124 125/* 126 * DSC polling parameters. 127 * 128 * Polling for DSC (a single bit in the status register) is a very 129 * important function in ide-tape. There are two cases in which we 130 * poll for DSC: 131 * 132 * 1. Before a read/write packet command, to ensure that we 133 * can transfer data from/to the tape's data buffers, without 134 * causing an actual media access. In case the tape is not 135 * ready yet, we take out our request from the device 136 * request queue, so that ide.c will service requests from 137 * the other device on the same interface meanwhile. 138 * 139 * 2. After the successful initialization of a "media access 140 * packet command", which is a command which can take a long 141 * time to complete (it can be several seconds or even an hour). 142 * 143 * Again, we postpone our request in the middle to free the bus 144 * for the other device. The polling frequency here should be 145 * lower than the read/write frequency since those media access 146 * commands are slow. We start from a "fast" frequency - 147 * IDETAPE_DSC_MA_FAST (one second), and if we don't receive DSC 148 * after IDETAPE_DSC_MA_THRESHOLD (5 minutes), we switch it to a 149 * lower frequency - IDETAPE_DSC_MA_SLOW (1 minute). 150 * 151 * We also set a timeout for the timer, in case something goes wrong. 152 * The timeout should be longer then the maximum execution time of a 153 * tape operation. 154 */ 155 156/* 157 * DSC timings. 158 */ 159#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */ 160#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */ 161#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */ 162#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */ 163#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */ 164#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */ 165#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */ 166 167/*************************** End of tunable parameters ***********************/ 168 169/* 170 * Read/Write error simulation 171 */ 172#define SIMULATE_ERRORS 0 173 174/* 175 * For general magnetic tape device compatibility. 176 */ 177typedef enum { 178 idetape_direction_none, 179 idetape_direction_read, 180 idetape_direction_write 181} idetape_chrdev_direction_t; 182 183struct idetape_bh { 184 u32 b_size; 185 atomic_t b_count; 186 struct idetape_bh *b_reqnext; 187 char *b_data; 188}; 189 190/* 191 * Our view of a packet command. 192 */ 193typedef struct idetape_packet_command_s { 194 u8 c[12]; /* Actual packet bytes */ 195 int retries; /* On each retry, we increment retries */ 196 int error; /* Error code */ 197 int request_transfer; /* Bytes to transfer */ 198 int actually_transferred; /* Bytes actually transferred */ 199 int buffer_size; /* Size of our data buffer */ 200 struct idetape_bh *bh; 201 char *b_data; 202 int b_count; 203 u8 *buffer; /* Data buffer */ 204 u8 *current_position; /* Pointer into the above buffer */ 205 ide_startstop_t (*callback) (ide_drive_t *); /* Called when this packet command is completed */ 206 u8 pc_buffer[IDETAPE_PC_BUFFER_SIZE]; /* Temporary buffer */ 207 unsigned long flags; /* Status/Action bit flags: long for set_bit */ 208} idetape_pc_t; 209 210/* 211 * Packet command flag bits. 212 */ 213/* Set when an error is considered normal - We won't retry */ 214#define PC_ABORT 0 215/* 1 When polling for DSC on a media access command */ 216#define PC_WAIT_FOR_DSC 1 217/* 1 when we prefer to use DMA if possible */ 218#define PC_DMA_RECOMMENDED 2 219/* 1 while DMA in progress */ 220#define PC_DMA_IN_PROGRESS 3 221/* 1 when encountered problem during DMA */ 222#define PC_DMA_ERROR 4 223/* Data direction */ 224#define PC_WRITING 5 225 226/* 227 * A pipeline stage. 228 */ 229typedef struct idetape_stage_s { 230 struct request rq; /* The corresponding request */ 231 struct idetape_bh *bh; /* The data buffers */ 232 struct idetape_stage_s *next; /* Pointer to the next stage */ 233} idetape_stage_t; 234 235/* 236 * Most of our global data which we need to save even as we leave the 237 * driver due to an interrupt or a timer event is stored in a variable 238 * of type idetape_tape_t, defined below. 239 */ 240typedef struct ide_tape_obj { 241 ide_drive_t *drive; 242 ide_driver_t *driver; 243 struct gendisk *disk; 244 struct kref kref; 245 246 /* 247 * Since a typical character device operation requires more 248 * than one packet command, we provide here enough memory 249 * for the maximum of interconnected packet commands. 250 * The packet commands are stored in the circular array pc_stack. 251 * pc_stack_index points to the last used entry, and warps around 252 * to the start when we get to the last array entry. 253 * 254 * pc points to the current processed packet command. 255 * 256 * failed_pc points to the last failed packet command, or contains 257 * NULL if we do not need to retry any packet command. This is 258 * required since an additional packet command is needed before the 259 * retry, to get detailed information on what went wrong. 260 */ 261 /* Current packet command */ 262 idetape_pc_t *pc; 263 /* Last failed packet command */ 264 idetape_pc_t *failed_pc; 265 /* Packet command stack */ 266 idetape_pc_t pc_stack[IDETAPE_PC_STACK]; 267 /* Next free packet command storage space */ 268 int pc_stack_index; 269 struct request rq_stack[IDETAPE_PC_STACK]; 270 /* We implement a circular array */ 271 int rq_stack_index; 272 273 /* 274 * DSC polling variables. 275 * 276 * While polling for DSC we use postponed_rq to postpone the 277 * current request so that ide.c will be able to service 278 * pending requests on the other device. Note that at most 279 * we will have only one DSC (usually data transfer) request 280 * in the device request queue. Additional requests can be 281 * queued in our internal pipeline, but they will be visible 282 * to ide.c only one at a time. 283 */ 284 struct request *postponed_rq; 285 /* The time in which we started polling for DSC */ 286 unsigned long dsc_polling_start; 287 /* Timer used to poll for dsc */ 288 struct timer_list dsc_timer; 289 /* Read/Write dsc polling frequency */ 290 unsigned long best_dsc_rw_frequency; 291 /* The current polling frequency */ 292 unsigned long dsc_polling_frequency; 293 /* Maximum waiting time */ 294 unsigned long dsc_timeout; 295 296 /* 297 * Read position information 298 */ 299 u8 partition; 300 /* Current block */ 301 unsigned int first_frame_position; 302 unsigned int last_frame_position; 303 unsigned int blocks_in_buffer; 304 305 /* 306 * Last error information 307 */ 308 u8 sense_key, asc, ascq; 309 310 /* 311 * Character device operation 312 */ 313 unsigned int minor; 314 /* device name */ 315 char name[4]; 316 /* Current character device data transfer direction */ 317 idetape_chrdev_direction_t chrdev_direction; 318 319 /* 320 * Device information 321 */ 322 /* Usually 512 or 1024 bytes */ 323 unsigned short tape_block_size; 324 int user_bs_factor; 325 326 /* Copy of the tape's Capabilities and Mechanical Page */ 327 u8 caps[20]; 328 329 /* 330 * Active data transfer request parameters. 331 * 332 * At most, there is only one ide-tape originated data transfer 333 * request in the device request queue. This allows ide.c to 334 * easily service requests from the other device when we 335 * postpone our active request. In the pipelined operation 336 * mode, we use our internal pipeline structure to hold 337 * more data requests. 338 * 339 * The data buffer size is chosen based on the tape's 340 * recommendation. 341 */ 342 /* Pointer to the request which is waiting in the device request queue */ 343 struct request *active_data_request; 344 /* Data buffer size (chosen based on the tape's recommendation */ 345 int stage_size; 346 idetape_stage_t *merge_stage; 347 int merge_stage_size; 348 struct idetape_bh *bh; 349 char *b_data; 350 int b_count; 351 352 /* 353 * Pipeline parameters. 354 * 355 * To accomplish non-pipelined mode, we simply set the following 356 * variables to zero (or NULL, where appropriate). 357 */ 358 /* Number of currently used stages */ 359 int nr_stages; 360 /* Number of pending stages */ 361 int nr_pending_stages; 362 /* We will not allocate more than this number of stages */ 363 int max_stages, min_pipeline, max_pipeline; 364 /* The first stage which will be removed from the pipeline */ 365 idetape_stage_t *first_stage; 366 /* The currently active stage */ 367 idetape_stage_t *active_stage; 368 /* Will be serviced after the currently active request */ 369 idetape_stage_t *next_stage; 370 /* New requests will be added to the pipeline here */ 371 idetape_stage_t *last_stage; 372 /* Optional free stage which we can use */ 373 idetape_stage_t *cache_stage; 374 int pages_per_stage; 375 /* Wasted space in each stage */ 376 int excess_bh_size; 377 378 /* Status/Action flags: long for set_bit */ 379 unsigned long flags; 380 /* protects the ide-tape queue */ 381 spinlock_t spinlock; 382 383 /* 384 * Measures average tape speed 385 */ 386 unsigned long avg_time; 387 int avg_size; 388 int avg_speed; 389 390 char vendor_id[10]; 391 char product_id[18]; 392 char firmware_revision[6]; 393 int firmware_revision_num; 394 395 /* the door is currently locked */ 396 int door_locked; 397 /* the tape hardware is write protected */ 398 char drv_write_prot; 399 /* the tape is write protected (hardware or opened as read-only) */ 400 char write_prot; 401 402 /* 403 * Limit the number of times a request can 404 * be postponed, to avoid an infinite postpone 405 * deadlock. 406 */ 407 /* request postpone count limit */ 408 int postpone_cnt; 409 410 /* 411 * Measures number of frames: 412 * 413 * 1. written/read to/from the driver pipeline (pipeline_head). 414 * 2. written/read to/from the tape buffers (idetape_bh). 415 * 3. written/read by the tape to/from the media (tape_head). 416 */ 417 int pipeline_head; 418 int buffer_head; 419 int tape_head; 420 int last_tape_head; 421 422 /* 423 * Speed control at the tape buffers input/output 424 */ 425 unsigned long insert_time; 426 int insert_size; 427 int insert_speed; 428 int max_insert_speed; 429 int measure_insert_time; 430 431 /* 432 * Measure tape still time, in milliseconds 433 */ 434 unsigned long tape_still_time_begin; 435 int tape_still_time; 436 437 /* 438 * Speed regulation negative feedback loop 439 */ 440 int speed_control; 441 int pipeline_head_speed; 442 int controlled_pipeline_head_speed; 443 int uncontrolled_pipeline_head_speed; 444 int controlled_last_pipeline_head; 445 int uncontrolled_last_pipeline_head; 446 unsigned long uncontrolled_pipeline_head_time; 447 unsigned long controlled_pipeline_head_time; 448 int controlled_previous_pipeline_head; 449 int uncontrolled_previous_pipeline_head; 450 unsigned long controlled_previous_head_time; 451 unsigned long uncontrolled_previous_head_time; 452 int restart_speed_control_req; 453 454 /* 455 * Debug_level determines amount of debugging output; 456 * can be changed using /proc/ide/hdx/settings 457 * 0 : almost no debugging output 458 * 1 : 0+output errors only 459 * 2 : 1+output all sensekey/asc 460 * 3 : 2+follow all chrdev related procedures 461 * 4 : 3+follow all procedures 462 * 5 : 4+include pc_stack rq_stack info 463 * 6 : 5+USE_COUNT updates 464 */ 465 int debug_level; 466} idetape_tape_t; 467 468static DEFINE_MUTEX(idetape_ref_mutex); 469 470static struct class *idetape_sysfs_class; 471 472#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref) 473 474#define ide_tape_g(disk) \ 475 container_of((disk)->private_data, struct ide_tape_obj, driver) 476 477static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 478{ 479 struct ide_tape_obj *tape = NULL; 480 481 mutex_lock(&idetape_ref_mutex); 482 tape = ide_tape_g(disk); 483 if (tape) 484 kref_get(&tape->kref); 485 mutex_unlock(&idetape_ref_mutex); 486 return tape; 487} 488 489static void ide_tape_release(struct kref *); 490 491static void ide_tape_put(struct ide_tape_obj *tape) 492{ 493 mutex_lock(&idetape_ref_mutex); 494 kref_put(&tape->kref, ide_tape_release); 495 mutex_unlock(&idetape_ref_mutex); 496} 497 498/* 499 * Tape door status 500 */ 501#define DOOR_UNLOCKED 0 502#define DOOR_LOCKED 1 503#define DOOR_EXPLICITLY_LOCKED 2 504 505/* 506 * Tape flag bits values. 507 */ 508#define IDETAPE_IGNORE_DSC 0 509#define IDETAPE_ADDRESS_VALID 1 /* 0 When the tape position is unknown */ 510#define IDETAPE_BUSY 2 /* Device already opened */ 511#define IDETAPE_PIPELINE_ERROR 3 /* Error detected in a pipeline stage */ 512#define IDETAPE_DETECT_BS 4 /* Attempt to auto-detect the current user block size */ 513#define IDETAPE_FILEMARK 5 /* Currently on a filemark */ 514#define IDETAPE_DRQ_INTERRUPT 6 /* DRQ interrupt device */ 515#define IDETAPE_READ_ERROR 7 516#define IDETAPE_PIPELINE_ACTIVE 8 /* pipeline active */ 517/* 0 = no tape is loaded, so we don't rewind after ejecting */ 518#define IDETAPE_MEDIUM_PRESENT 9 519 520/* 521 * Some defines for the READ BUFFER command 522 */ 523#define IDETAPE_RETRIEVE_FAULTY_BLOCK 6 524 525/* 526 * Some defines for the SPACE command 527 */ 528#define IDETAPE_SPACE_OVER_FILEMARK 1 529#define IDETAPE_SPACE_TO_EOD 3 530 531/* 532 * Some defines for the LOAD UNLOAD command 533 */ 534#define IDETAPE_LU_LOAD_MASK 1 535#define IDETAPE_LU_RETENSION_MASK 2 536#define IDETAPE_LU_EOT_MASK 4 537 538/* 539 * Special requests for our block device strategy routine. 540 * 541 * In order to service a character device command, we add special 542 * requests to the tail of our block device request queue and wait 543 * for their completion. 544 */ 545 546enum { 547 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */ 548 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */ 549 REQ_IDETAPE_READ = (1 << 2), 550 REQ_IDETAPE_WRITE = (1 << 3), 551 REQ_IDETAPE_READ_BUFFER = (1 << 4), 552}; 553 554/* 555 * Error codes which are returned in rq->errors to the higher part 556 * of the driver. 557 */ 558#define IDETAPE_ERROR_GENERAL 101 559#define IDETAPE_ERROR_FILEMARK 102 560#define IDETAPE_ERROR_EOD 103 561 562/* 563 * The following is used to format the general configuration word of 564 * the ATAPI IDENTIFY DEVICE command. 565 */ 566struct idetape_id_gcw { 567 unsigned packet_size :2; /* Packet Size */ 568 unsigned reserved234 :3; /* Reserved */ 569 unsigned drq_type :2; /* Command packet DRQ type */ 570 unsigned removable :1; /* Removable media */ 571 unsigned device_type :5; /* Device type */ 572 unsigned reserved13 :1; /* Reserved */ 573 unsigned protocol :2; /* Protocol type */ 574}; 575 576/* 577 * READ POSITION packet command - Data Format (From Table 6-57) 578 */ 579typedef struct { 580 unsigned reserved0_10 :2; /* Reserved */ 581 unsigned bpu :1; /* Block Position Unknown */ 582 unsigned reserved0_543 :3; /* Reserved */ 583 unsigned eop :1; /* End Of Partition */ 584 unsigned bop :1; /* Beginning Of Partition */ 585 u8 partition; /* Partition Number */ 586 u8 reserved2, reserved3; /* Reserved */ 587 u32 first_block; /* First Block Location */ 588 u32 last_block; /* Last Block Location (Optional) */ 589 u8 reserved12; /* Reserved */ 590 u8 blocks_in_buffer[3]; /* Blocks In Buffer - (Optional) */ 591 u32 bytes_in_buffer; /* Bytes In Buffer (Optional) */ 592} idetape_read_position_result_t; 593 594/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 595#define IDETAPE_BLOCK_DESCRIPTOR 0 596#define IDETAPE_CAPABILITIES_PAGE 0x2a 597 598/* 599 * The variables below are used for the character device interface. 600 * Additional state variables are defined in our ide_drive_t structure. 601 */ 602static struct ide_tape_obj * idetape_devs[MAX_HWIFS * MAX_DRIVES]; 603 604#define ide_tape_f(file) ((file)->private_data) 605 606static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 607{ 608 struct ide_tape_obj *tape = NULL; 609 610 mutex_lock(&idetape_ref_mutex); 611 tape = idetape_devs[i]; 612 if (tape) 613 kref_get(&tape->kref); 614 mutex_unlock(&idetape_ref_mutex); 615 return tape; 616} 617 618/* 619 * Function declarations 620 * 621 */ 622static int idetape_chrdev_release (struct inode *inode, struct file *filp); 623static void idetape_write_release (ide_drive_t *drive, unsigned int minor); 624 625/* 626 * Too bad. The drive wants to send us data which we are not ready to accept. 627 * Just throw it away. 628 */ 629static void idetape_discard_data (ide_drive_t *drive, unsigned int bcount) 630{ 631 while (bcount--) 632 (void) HWIF(drive)->INB(IDE_DATA_REG); 633} 634 635static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount) 636{ 637 struct idetape_bh *bh = pc->bh; 638 int count; 639 640 while (bcount) { 641 if (bh == NULL) { 642 printk(KERN_ERR "ide-tape: bh == NULL in " 643 "idetape_input_buffers\n"); 644 idetape_discard_data(drive, bcount); 645 return; 646 } 647 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount); 648 HWIF(drive)->atapi_input_bytes(drive, bh->b_data + atomic_read(&bh->b_count), count); 649 bcount -= count; 650 atomic_add(count, &bh->b_count); 651 if (atomic_read(&bh->b_count) == bh->b_size) { 652 bh = bh->b_reqnext; 653 if (bh) 654 atomic_set(&bh->b_count, 0); 655 } 656 } 657 pc->bh = bh; 658} 659 660static void idetape_output_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount) 661{ 662 struct idetape_bh *bh = pc->bh; 663 int count; 664 665 while (bcount) { 666 if (bh == NULL) { 667 printk(KERN_ERR "ide-tape: bh == NULL in " 668 "idetape_output_buffers\n"); 669 return; 670 } 671 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 672 HWIF(drive)->atapi_output_bytes(drive, pc->b_data, count); 673 bcount -= count; 674 pc->b_data += count; 675 pc->b_count -= count; 676 if (!pc->b_count) { 677 pc->bh = bh = bh->b_reqnext; 678 if (bh) { 679 pc->b_data = bh->b_data; 680 pc->b_count = atomic_read(&bh->b_count); 681 } 682 } 683 } 684} 685 686static void idetape_update_buffers (idetape_pc_t *pc) 687{ 688 struct idetape_bh *bh = pc->bh; 689 int count; 690 unsigned int bcount = pc->actually_transferred; 691 692 if (test_bit(PC_WRITING, &pc->flags)) 693 return; 694 while (bcount) { 695 if (bh == NULL) { 696 printk(KERN_ERR "ide-tape: bh == NULL in " 697 "idetape_update_buffers\n"); 698 return; 699 } 700 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 701 atomic_set(&bh->b_count, count); 702 if (atomic_read(&bh->b_count) == bh->b_size) 703 bh = bh->b_reqnext; 704 bcount -= count; 705 } 706 pc->bh = bh; 707} 708 709/* 710 * idetape_next_pc_storage returns a pointer to a place in which we can 711 * safely store a packet command, even though we intend to leave the 712 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet 713 * commands is allocated at initialization time. 714 */ 715static idetape_pc_t *idetape_next_pc_storage (ide_drive_t *drive) 716{ 717 idetape_tape_t *tape = drive->driver_data; 718 719#if IDETAPE_DEBUG_LOG 720 if (tape->debug_level >= 5) 721 printk(KERN_INFO "ide-tape: pc_stack_index=%d\n", 722 tape->pc_stack_index); 723#endif /* IDETAPE_DEBUG_LOG */ 724 if (tape->pc_stack_index == IDETAPE_PC_STACK) 725 tape->pc_stack_index=0; 726 return (&tape->pc_stack[tape->pc_stack_index++]); 727} 728 729/* 730 * idetape_next_rq_storage is used along with idetape_next_pc_storage. 731 * Since we queue packet commands in the request queue, we need to 732 * allocate a request, along with the allocation of a packet command. 733 */ 734 735/************************************************************** 736 * * 737 * This should get fixed to use kmalloc(.., GFP_ATOMIC) * 738 * followed later on by kfree(). -ml * 739 * * 740 **************************************************************/ 741 742static struct request *idetape_next_rq_storage (ide_drive_t *drive) 743{ 744 idetape_tape_t *tape = drive->driver_data; 745 746#if IDETAPE_DEBUG_LOG 747 if (tape->debug_level >= 5) 748 printk(KERN_INFO "ide-tape: rq_stack_index=%d\n", 749 tape->rq_stack_index); 750#endif /* IDETAPE_DEBUG_LOG */ 751 if (tape->rq_stack_index == IDETAPE_PC_STACK) 752 tape->rq_stack_index=0; 753 return (&tape->rq_stack[tape->rq_stack_index++]); 754} 755 756/* 757 * idetape_init_pc initializes a packet command. 758 */ 759static void idetape_init_pc (idetape_pc_t *pc) 760{ 761 memset(pc->c, 0, 12); 762 pc->retries = 0; 763 pc->flags = 0; 764 pc->request_transfer = 0; 765 pc->buffer = pc->pc_buffer; 766 pc->buffer_size = IDETAPE_PC_BUFFER_SIZE; 767 pc->bh = NULL; 768 pc->b_data = NULL; 769} 770 771/* 772 * called on each failed packet command retry to analyze the request sense. We 773 * currently do not utilize this information. 774 */ 775static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 776{ 777 idetape_tape_t *tape = drive->driver_data; 778 idetape_pc_t *pc = tape->failed_pc; 779 780 tape->sense_key = sense[2] & 0xF; 781 tape->asc = sense[12]; 782 tape->ascq = sense[13]; 783#if IDETAPE_DEBUG_LOG 784 /* 785 * Without debugging, we only log an error if we decided to give up 786 * retrying. 787 */ 788 if (tape->debug_level >= 1) 789 printk(KERN_INFO "ide-tape: pc = %x, sense key = %x, " 790 "asc = %x, ascq = %x\n", 791 pc->c[0], tape->sense_key, 792 tape->asc, tape->ascq); 793#endif /* IDETAPE_DEBUG_LOG */ 794 795 /* Correct pc->actually_transferred by asking the tape. */ 796 if (test_bit(PC_DMA_ERROR, &pc->flags)) { 797 pc->actually_transferred = pc->request_transfer - 798 tape->tape_block_size * 799 be32_to_cpu(get_unaligned((u32 *)&sense[3])); 800 idetape_update_buffers(pc); 801 } 802 803 /* 804 * If error was the result of a zero-length read or write command, 805 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 806 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 807 */ 808 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 809 /* length == 0 */ 810 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 811 if (tape->sense_key == 5) { 812 /* don't report an error, everything's ok */ 813 pc->error = 0; 814 /* don't retry read/write */ 815 set_bit(PC_ABORT, &pc->flags); 816 } 817 } 818 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 819 pc->error = IDETAPE_ERROR_FILEMARK; 820 set_bit(PC_ABORT, &pc->flags); 821 } 822 if (pc->c[0] == WRITE_6) { 823 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 824 && tape->asc == 0x0 && tape->ascq == 0x2)) { 825 pc->error = IDETAPE_ERROR_EOD; 826 set_bit(PC_ABORT, &pc->flags); 827 } 828 } 829 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 830 if (tape->sense_key == 8) { 831 pc->error = IDETAPE_ERROR_EOD; 832 set_bit(PC_ABORT, &pc->flags); 833 } 834 if (!test_bit(PC_ABORT, &pc->flags) && 835 pc->actually_transferred) 836 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 837 } 838} 839 840static void idetape_activate_next_stage(ide_drive_t *drive) 841{ 842 idetape_tape_t *tape = drive->driver_data; 843 idetape_stage_t *stage = tape->next_stage; 844 struct request *rq = &stage->rq; 845 846#if IDETAPE_DEBUG_LOG 847 if (tape->debug_level >= 4) 848 printk(KERN_INFO "ide-tape: Reached idetape_active_next_stage\n"); 849#endif /* IDETAPE_DEBUG_LOG */ 850 if (stage == NULL) { 851 printk(KERN_ERR "ide-tape: bug: Trying to activate a non existing stage\n"); 852 return; 853 } 854 855 rq->rq_disk = tape->disk; 856 rq->buffer = NULL; 857 rq->special = (void *)stage->bh; 858 tape->active_data_request = rq; 859 tape->active_stage = stage; 860 tape->next_stage = stage->next; 861} 862 863/* 864 * idetape_increase_max_pipeline_stages is a part of the feedback 865 * loop which tries to find the optimum number of stages. In the 866 * feedback loop, we are starting from a minimum maximum number of 867 * stages, and if we sense that the pipeline is empty, we try to 868 * increase it, until we reach the user compile time memory limit. 869 */ 870static void idetape_increase_max_pipeline_stages (ide_drive_t *drive) 871{ 872 idetape_tape_t *tape = drive->driver_data; 873 int increase = (tape->max_pipeline - tape->min_pipeline) / 10; 874 875#if IDETAPE_DEBUG_LOG 876 if (tape->debug_level >= 4) 877 printk (KERN_INFO "ide-tape: Reached idetape_increase_max_pipeline_stages\n"); 878#endif /* IDETAPE_DEBUG_LOG */ 879 880 tape->max_stages += max(increase, 1); 881 tape->max_stages = max(tape->max_stages, tape->min_pipeline); 882 tape->max_stages = min(tape->max_stages, tape->max_pipeline); 883} 884 885/* 886 * idetape_kfree_stage calls kfree to completely free a stage, along with 887 * its related buffers. 888 */ 889static void __idetape_kfree_stage (idetape_stage_t *stage) 890{ 891 struct idetape_bh *prev_bh, *bh = stage->bh; 892 int size; 893 894 while (bh != NULL) { 895 if (bh->b_data != NULL) { 896 size = (int) bh->b_size; 897 while (size > 0) { 898 free_page((unsigned long) bh->b_data); 899 size -= PAGE_SIZE; 900 bh->b_data += PAGE_SIZE; 901 } 902 } 903 prev_bh = bh; 904 bh = bh->b_reqnext; 905 kfree(prev_bh); 906 } 907 kfree(stage); 908} 909 910static void idetape_kfree_stage (idetape_tape_t *tape, idetape_stage_t *stage) 911{ 912 __idetape_kfree_stage(stage); 913} 914 915/* 916 * idetape_remove_stage_head removes tape->first_stage from the pipeline. 917 * The caller should avoid race conditions. 918 */ 919static void idetape_remove_stage_head (ide_drive_t *drive) 920{ 921 idetape_tape_t *tape = drive->driver_data; 922 idetape_stage_t *stage; 923 924#if IDETAPE_DEBUG_LOG 925 if (tape->debug_level >= 4) 926 printk(KERN_INFO "ide-tape: Reached idetape_remove_stage_head\n"); 927#endif /* IDETAPE_DEBUG_LOG */ 928 if (tape->first_stage == NULL) { 929 printk(KERN_ERR "ide-tape: bug: tape->first_stage is NULL\n"); 930 return; 931 } 932 if (tape->active_stage == tape->first_stage) { 933 printk(KERN_ERR "ide-tape: bug: Trying to free our active pipeline stage\n"); 934 return; 935 } 936 stage = tape->first_stage; 937 tape->first_stage = stage->next; 938 idetape_kfree_stage(tape, stage); 939 tape->nr_stages--; 940 if (tape->first_stage == NULL) { 941 tape->last_stage = NULL; 942 if (tape->next_stage != NULL) 943 printk(KERN_ERR "ide-tape: bug: tape->next_stage != NULL\n"); 944 if (tape->nr_stages) 945 printk(KERN_ERR "ide-tape: bug: nr_stages should be 0 now\n"); 946 } 947} 948 949/* 950 * This will free all the pipeline stages starting from new_last_stage->next 951 * to the end of the list, and point tape->last_stage to new_last_stage. 952 */ 953static void idetape_abort_pipeline(ide_drive_t *drive, 954 idetape_stage_t *new_last_stage) 955{ 956 idetape_tape_t *tape = drive->driver_data; 957 idetape_stage_t *stage = new_last_stage->next; 958 idetape_stage_t *nstage; 959 960#if IDETAPE_DEBUG_LOG 961 if (tape->debug_level >= 4) 962 printk(KERN_INFO "ide-tape: %s: idetape_abort_pipeline called\n", tape->name); 963#endif 964 while (stage) { 965 nstage = stage->next; 966 idetape_kfree_stage(tape, stage); 967 --tape->nr_stages; 968 --tape->nr_pending_stages; 969 stage = nstage; 970 } 971 if (new_last_stage) 972 new_last_stage->next = NULL; 973 tape->last_stage = new_last_stage; 974 tape->next_stage = NULL; 975} 976 977/* 978 * idetape_end_request is used to finish servicing a request, and to 979 * insert a pending pipeline request into the main device queue. 980 */ 981static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 982{ 983 struct request *rq = HWGROUP(drive)->rq; 984 idetape_tape_t *tape = drive->driver_data; 985 unsigned long flags; 986 int error; 987 int remove_stage = 0; 988 idetape_stage_t *active_stage; 989 990#if IDETAPE_DEBUG_LOG 991 if (tape->debug_level >= 4) 992 printk(KERN_INFO "ide-tape: Reached idetape_end_request\n"); 993#endif /* IDETAPE_DEBUG_LOG */ 994 995 switch (uptodate) { 996 case 0: error = IDETAPE_ERROR_GENERAL; break; 997 case 1: error = 0; break; 998 default: error = uptodate; 999 } 1000 rq->errors = error; 1001 if (error) 1002 tape->failed_pc = NULL; 1003 1004 if (!blk_special_request(rq)) { 1005 ide_end_request(drive, uptodate, nr_sects); 1006 return 0; 1007 } 1008 1009 spin_lock_irqsave(&tape->spinlock, flags); 1010 1011 /* The request was a pipelined data transfer request */ 1012 if (tape->active_data_request == rq) { 1013 active_stage = tape->active_stage; 1014 tape->active_stage = NULL; 1015 tape->active_data_request = NULL; 1016 tape->nr_pending_stages--; 1017 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 1018 remove_stage = 1; 1019 if (error) { 1020 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 1021 if (error == IDETAPE_ERROR_EOD) 1022 idetape_abort_pipeline(drive, active_stage); 1023 } 1024 } else if (rq->cmd[0] & REQ_IDETAPE_READ) { 1025 if (error == IDETAPE_ERROR_EOD) { 1026 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 1027 idetape_abort_pipeline(drive, active_stage); 1028 } 1029 } 1030 if (tape->next_stage != NULL) { 1031 idetape_activate_next_stage(drive); 1032 1033 /* 1034 * Insert the next request into the request queue. 1035 */ 1036 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end); 1037 } else if (!error) { 1038 idetape_increase_max_pipeline_stages(drive); 1039 } 1040 } 1041 ide_end_drive_cmd(drive, 0, 0); 1042// blkdev_dequeue_request(rq); 1043// drive->rq = NULL; 1044// end_that_request_last(rq); 1045 1046 if (remove_stage) 1047 idetape_remove_stage_head(drive); 1048 if (tape->active_data_request == NULL) 1049 clear_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags); 1050 spin_unlock_irqrestore(&tape->spinlock, flags); 1051 return 0; 1052} 1053 1054static ide_startstop_t idetape_request_sense_callback (ide_drive_t *drive) 1055{ 1056 idetape_tape_t *tape = drive->driver_data; 1057 1058#if IDETAPE_DEBUG_LOG 1059 if (tape->debug_level >= 4) 1060 printk(KERN_INFO "ide-tape: Reached idetape_request_sense_callback\n"); 1061#endif /* IDETAPE_DEBUG_LOG */ 1062 if (!tape->pc->error) { 1063 idetape_analyze_error(drive, tape->pc->buffer); 1064 idetape_end_request(drive, 1, 0); 1065 } else { 1066 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE itself - Aborting request!\n"); 1067 idetape_end_request(drive, 0, 0); 1068 } 1069 return ide_stopped; 1070} 1071 1072static void idetape_create_request_sense_cmd (idetape_pc_t *pc) 1073{ 1074 idetape_init_pc(pc); 1075 pc->c[0] = REQUEST_SENSE; 1076 pc->c[4] = 20; 1077 pc->request_transfer = 20; 1078 pc->callback = &idetape_request_sense_callback; 1079} 1080 1081static void idetape_init_rq(struct request *rq, u8 cmd) 1082{ 1083 memset(rq, 0, sizeof(*rq)); 1084 rq->cmd_type = REQ_TYPE_SPECIAL; 1085 rq->cmd[0] = cmd; 1086} 1087 1088/* 1089 * idetape_queue_pc_head generates a new packet command request in front 1090 * of the request queue, before the current request, so that it will be 1091 * processed immediately, on the next pass through the driver. 1092 * 1093 * idetape_queue_pc_head is called from the request handling part of 1094 * the driver (the "bottom" part). Safe storage for the request should 1095 * be allocated with idetape_next_pc_storage and idetape_next_rq_storage 1096 * before calling idetape_queue_pc_head. 1097 * 1098 * Memory for those requests is pre-allocated at initialization time, and 1099 * is limited to IDETAPE_PC_STACK requests. We assume that we have enough 1100 * space for the maximum possible number of inter-dependent packet commands. 1101 * 1102 * The higher level of the driver - The ioctl handler and the character 1103 * device handling functions should queue request to the lower level part 1104 * and wait for their completion using idetape_queue_pc_tail or 1105 * idetape_queue_rw_tail. 1106 */ 1107static void idetape_queue_pc_head (ide_drive_t *drive, idetape_pc_t *pc,struct request *rq) 1108{ 1109 struct ide_tape_obj *tape = drive->driver_data; 1110 1111 idetape_init_rq(rq, REQ_IDETAPE_PC1); 1112 rq->buffer = (char *) pc; 1113 rq->rq_disk = tape->disk; 1114 (void) ide_do_drive_cmd(drive, rq, ide_preempt); 1115} 1116 1117/* 1118 * idetape_retry_pc is called when an error was detected during the 1119 * last packet command. We queue a request sense packet command in 1120 * the head of the request list. 1121 */ 1122static ide_startstop_t idetape_retry_pc (ide_drive_t *drive) 1123{ 1124 idetape_tape_t *tape = drive->driver_data; 1125 idetape_pc_t *pc; 1126 struct request *rq; 1127 1128 (void)drive->hwif->INB(IDE_ERROR_REG); 1129 pc = idetape_next_pc_storage(drive); 1130 rq = idetape_next_rq_storage(drive); 1131 idetape_create_request_sense_cmd(pc); 1132 set_bit(IDETAPE_IGNORE_DSC, &tape->flags); 1133 idetape_queue_pc_head(drive, pc, rq); 1134 return ide_stopped; 1135} 1136 1137/* 1138 * idetape_postpone_request postpones the current request so that 1139 * ide.c will be able to service requests from another device on 1140 * the same hwgroup while we are polling for DSC. 1141 */ 1142static void idetape_postpone_request (ide_drive_t *drive) 1143{ 1144 idetape_tape_t *tape = drive->driver_data; 1145 1146#if IDETAPE_DEBUG_LOG 1147 if (tape->debug_level >= 4) 1148 printk(KERN_INFO "ide-tape: idetape_postpone_request\n"); 1149#endif 1150 tape->postponed_rq = HWGROUP(drive)->rq; 1151 ide_stall_queue(drive, tape->dsc_polling_frequency); 1152} 1153 1154/* 1155 * idetape_pc_intr is the usual interrupt handler which will be called 1156 * during a packet command. We will transfer some of the data (as 1157 * requested by the drive) and will re-point interrupt handler to us. 1158 * When data transfer is finished, we will act according to the 1159 * algorithm described before idetape_issue_packet_command. 1160 * 1161 */ 1162static ide_startstop_t idetape_pc_intr (ide_drive_t *drive) 1163{ 1164 ide_hwif_t *hwif = drive->hwif; 1165 idetape_tape_t *tape = drive->driver_data; 1166 idetape_pc_t *pc = tape->pc; 1167 unsigned int temp; 1168#if SIMULATE_ERRORS 1169 static int error_sim_count = 0; 1170#endif 1171 u16 bcount; 1172 u8 stat, ireason; 1173 1174#if IDETAPE_DEBUG_LOG 1175 if (tape->debug_level >= 4) 1176 printk(KERN_INFO "ide-tape: Reached idetape_pc_intr " 1177 "interrupt handler\n"); 1178#endif /* IDETAPE_DEBUG_LOG */ 1179 1180 /* Clear the interrupt */ 1181 stat = ide_read_status(drive); 1182 1183 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) { 1184 if (hwif->ide_dma_end(drive) || (stat & ERR_STAT)) { 1185 /* 1186 * A DMA error is sometimes expected. For example, 1187 * if the tape is crossing a filemark during a 1188 * READ command, it will issue an irq and position 1189 * itself before the filemark, so that only a partial 1190 * data transfer will occur (which causes the DMA 1191 * error). In that case, we will later ask the tape 1192 * how much bytes of the original request were 1193 * actually transferred (we can't receive that 1194 * information from the DMA engine on most chipsets). 1195 */ 1196 1197 /* 1198 * On the contrary, a DMA error is never expected; 1199 * it usually indicates a hardware error or abort. 1200 * If the tape crosses a filemark during a READ 1201 * command, it will issue an irq and position itself 1202 * after the filemark (not before). Only a partial 1203 * data transfer will occur, but no DMA error. 1204 * (AS, 19 Apr 2001) 1205 */ 1206 set_bit(PC_DMA_ERROR, &pc->flags); 1207 } else { 1208 pc->actually_transferred = pc->request_transfer; 1209 idetape_update_buffers(pc); 1210 } 1211#if IDETAPE_DEBUG_LOG 1212 if (tape->debug_level >= 4) 1213 printk(KERN_INFO "ide-tape: DMA finished\n"); 1214#endif /* IDETAPE_DEBUG_LOG */ 1215 } 1216 1217 /* No more interrupts */ 1218 if ((stat & DRQ_STAT) == 0) { 1219#if IDETAPE_DEBUG_LOG 1220 if (tape->debug_level >= 2) 1221 printk(KERN_INFO "ide-tape: Packet command completed, %d bytes transferred\n", pc->actually_transferred); 1222#endif /* IDETAPE_DEBUG_LOG */ 1223 clear_bit(PC_DMA_IN_PROGRESS, &pc->flags); 1224 1225 local_irq_enable(); 1226 1227#if SIMULATE_ERRORS 1228 if ((pc->c[0] == WRITE_6 || pc->c[0] == READ_6) && 1229 (++error_sim_count % 100) == 0) { 1230 printk(KERN_INFO "ide-tape: %s: simulating error\n", 1231 tape->name); 1232 stat |= ERR_STAT; 1233 } 1234#endif 1235 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE) 1236 stat &= ~ERR_STAT; 1237 if ((stat & ERR_STAT) || test_bit(PC_DMA_ERROR, &pc->flags)) { 1238 /* Error detected */ 1239#if IDETAPE_DEBUG_LOG 1240 if (tape->debug_level >= 1) 1241 printk(KERN_INFO "ide-tape: %s: I/O error\n", 1242 tape->name); 1243#endif /* IDETAPE_DEBUG_LOG */ 1244 if (pc->c[0] == REQUEST_SENSE) { 1245 printk(KERN_ERR "ide-tape: I/O error in request sense command\n"); 1246 return ide_do_reset(drive); 1247 } 1248#if IDETAPE_DEBUG_LOG 1249 if (tape->debug_level >= 1) 1250 printk(KERN_INFO "ide-tape: [cmd %x]: check condition\n", pc->c[0]); 1251#endif 1252 /* Retry operation */ 1253 return idetape_retry_pc(drive); 1254 } 1255 pc->error = 0; 1256 if (test_bit(PC_WAIT_FOR_DSC, &pc->flags) && 1257 (stat & SEEK_STAT) == 0) { 1258 /* Media access command */ 1259 tape->dsc_polling_start = jiffies; 1260 tape->dsc_polling_frequency = IDETAPE_DSC_MA_FAST; 1261 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 1262 /* Allow ide.c to handle other requests */ 1263 idetape_postpone_request(drive); 1264 return ide_stopped; 1265 } 1266 if (tape->failed_pc == pc) 1267 tape->failed_pc = NULL; 1268 /* Command finished - Call the callback function */ 1269 return pc->callback(drive); 1270 } 1271 if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) { 1272 printk(KERN_ERR "ide-tape: The tape wants to issue more " 1273 "interrupts in DMA mode\n"); 1274 printk(KERN_ERR "ide-tape: DMA disabled, reverting to PIO\n"); 1275 ide_dma_off(drive); 1276 return ide_do_reset(drive); 1277 } 1278 /* Get the number of bytes to transfer on this interrupt. */ 1279 bcount = (hwif->INB(IDE_BCOUNTH_REG) << 8) | 1280 hwif->INB(IDE_BCOUNTL_REG); 1281 1282 ireason = hwif->INB(IDE_IREASON_REG); 1283 1284 if (ireason & CD) { 1285 printk(KERN_ERR "ide-tape: CoD != 0 in idetape_pc_intr\n"); 1286 return ide_do_reset(drive); 1287 } 1288 if (((ireason & IO) == IO) == test_bit(PC_WRITING, &pc->flags)) { 1289 /* Hopefully, we will never get here */ 1290 printk(KERN_ERR "ide-tape: We wanted to %s, ", 1291 (ireason & IO) ? "Write" : "Read"); 1292 printk(KERN_ERR "ide-tape: but the tape wants us to %s !\n", 1293 (ireason & IO) ? "Read" : "Write"); 1294 return ide_do_reset(drive); 1295 } 1296 if (!test_bit(PC_WRITING, &pc->flags)) { 1297 /* Reading - Check that we have enough space */ 1298 temp = pc->actually_transferred + bcount; 1299 if (temp > pc->request_transfer) { 1300 if (temp > pc->buffer_size) { 1301 printk(KERN_ERR "ide-tape: The tape wants to send us more data than expected - discarding data\n"); 1302 idetape_discard_data(drive, bcount); 1303 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 1304 return ide_started; 1305 } 1306#if IDETAPE_DEBUG_LOG 1307 if (tape->debug_level >= 2) 1308 printk(KERN_NOTICE "ide-tape: The tape wants to send us more data than expected - allowing transfer\n"); 1309#endif /* IDETAPE_DEBUG_LOG */ 1310 } 1311 } 1312 if (test_bit(PC_WRITING, &pc->flags)) { 1313 if (pc->bh != NULL) 1314 idetape_output_buffers(drive, pc, bcount); 1315 else 1316 /* Write the current buffer */ 1317 hwif->atapi_output_bytes(drive, pc->current_position, 1318 bcount); 1319 } else { 1320 if (pc->bh != NULL) 1321 idetape_input_buffers(drive, pc, bcount); 1322 else 1323 /* Read the current buffer */ 1324 hwif->atapi_input_bytes(drive, pc->current_position, 1325 bcount); 1326 } 1327 /* Update the current position */ 1328 pc->actually_transferred += bcount; 1329 pc->current_position += bcount; 1330#if IDETAPE_DEBUG_LOG 1331 if (tape->debug_level >= 2) 1332 printk(KERN_INFO "ide-tape: [cmd %x] transferred %d bytes " 1333 "on that interrupt\n", pc->c[0], bcount); 1334#endif 1335 /* And set the interrupt handler again */ 1336 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 1337 return ide_started; 1338} 1339 1340/* 1341 * Packet Command Interface 1342 * 1343 * The current Packet Command is available in tape->pc, and will not 1344 * change until we finish handling it. Each packet command is associated 1345 * with a callback function that will be called when the command is 1346 * finished. 1347 * 1348 * The handling will be done in three stages: 1349 * 1350 * 1. idetape_issue_packet_command will send the packet command to the 1351 * drive, and will set the interrupt handler to idetape_pc_intr. 1352 * 1353 * 2. On each interrupt, idetape_pc_intr will be called. This step 1354 * will be repeated until the device signals us that no more 1355 * interrupts will be issued. 1356 * 1357 * 3. ATAPI Tape media access commands have immediate status with a 1358 * delayed process. In case of a successful initiation of a 1359 * media access packet command, the DSC bit will be set when the 1360 * actual execution of the command is finished. 1361 * Since the tape drive will not issue an interrupt, we have to 1362 * poll for this event. In this case, we define the request as 1363 * "low priority request" by setting rq_status to 1364 * IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and exit 1365 * the driver. 1366 * 1367 * ide.c will then give higher priority to requests which 1368 * originate from the other device, until will change rq_status 1369 * to RQ_ACTIVE. 1370 * 1371 * 4. When the packet command is finished, it will be checked for errors. 1372 * 1373 * 5. In case an error was found, we queue a request sense packet 1374 * command in front of the request queue and retry the operation 1375 * up to IDETAPE_MAX_PC_RETRIES times. 1376 * 1377 * 6. In case no error was found, or we decided to give up and not 1378 * to retry again, the callback function will be called and then 1379 * we will handle the next request. 1380 * 1381 */ 1382static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 1383{ 1384 ide_hwif_t *hwif = drive->hwif; 1385 idetape_tape_t *tape = drive->driver_data; 1386 idetape_pc_t *pc = tape->pc; 1387 int retries = 100; 1388 ide_startstop_t startstop; 1389 u8 ireason; 1390 1391 if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) { 1392 printk(KERN_ERR "ide-tape: Strange, packet command initiated yet DRQ isn't asserted\n"); 1393 return startstop; 1394 } 1395 ireason = hwif->INB(IDE_IREASON_REG); 1396 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) { 1397 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while issuing " 1398 "a packet command, retrying\n"); 1399 udelay(100); 1400 ireason = hwif->INB(IDE_IREASON_REG); 1401 if (retries == 0) { 1402 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while " 1403 "issuing a packet command, ignoring\n"); 1404 ireason |= CD; 1405 ireason &= ~IO; 1406 } 1407 } 1408 if ((ireason & CD) == 0 || (ireason & IO)) { 1409 printk(KERN_ERR "ide-tape: (IO,CoD) != (0,1) while issuing " 1410 "a packet command\n"); 1411 return ide_do_reset(drive); 1412 } 1413 /* Set the interrupt routine */ 1414 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 1415#ifdef CONFIG_BLK_DEV_IDEDMA 1416 /* Begin DMA, if necessary */ 1417 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) 1418 hwif->dma_start(drive); 1419#endif 1420 /* Send the actual packet */ 1421 HWIF(drive)->atapi_output_bytes(drive, pc->c, 12); 1422 return ide_started; 1423} 1424 1425static ide_startstop_t idetape_issue_packet_command (ide_drive_t *drive, idetape_pc_t *pc) 1426{ 1427 ide_hwif_t *hwif = drive->hwif; 1428 idetape_tape_t *tape = drive->driver_data; 1429 int dma_ok = 0; 1430 u16 bcount; 1431 1432 if (tape->pc->c[0] == REQUEST_SENSE && 1433 pc->c[0] == REQUEST_SENSE) { 1434 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 1435 "Two request sense in serial were issued\n"); 1436 } 1437 1438 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 1439 tape->failed_pc = pc; 1440 /* Set the current packet command */ 1441 tape->pc = pc; 1442 1443 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 1444 test_bit(PC_ABORT, &pc->flags)) { 1445 /* 1446 * We will "abort" retrying a packet command in case 1447 * a legitimate error code was received (crossing a 1448 * filemark, or end of the media, for example). 1449 */ 1450 if (!test_bit(PC_ABORT, &pc->flags)) { 1451 if (!(pc->c[0] == TEST_UNIT_READY && 1452 tape->sense_key == 2 && tape->asc == 4 && 1453 (tape->ascq == 1 || tape->ascq == 8))) { 1454 printk(KERN_ERR "ide-tape: %s: I/O error, " 1455 "pc = %2x, key = %2x, " 1456 "asc = %2x, ascq = %2x\n", 1457 tape->name, pc->c[0], 1458 tape->sense_key, tape->asc, 1459 tape->ascq); 1460 } 1461 /* Giving up */ 1462 pc->error = IDETAPE_ERROR_GENERAL; 1463 } 1464 tape->failed_pc = NULL; 1465 return pc->callback(drive); 1466 } 1467#if IDETAPE_DEBUG_LOG 1468 if (tape->debug_level >= 2) 1469 printk(KERN_INFO "ide-tape: Retry number - %d, cmd = %02X\n", pc->retries, pc->c[0]); 1470#endif /* IDETAPE_DEBUG_LOG */ 1471 1472 pc->retries++; 1473 /* We haven't transferred any data yet */ 1474 pc->actually_transferred = 0; 1475 pc->current_position = pc->buffer; 1476 /* Request to transfer the entire buffer at once */ 1477 bcount = pc->request_transfer; 1478 1479 if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) { 1480 printk(KERN_WARNING "ide-tape: DMA disabled, " 1481 "reverting to PIO\n"); 1482 ide_dma_off(drive); 1483 } 1484 if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma) 1485 dma_ok = !hwif->dma_setup(drive); 1486 1487 ide_pktcmd_tf_load(drive, IDE_TFLAG_NO_SELECT_MASK | 1488 IDE_TFLAG_OUT_DEVICE, bcount, dma_ok); 1489 1490 if (dma_ok) /* Will begin DMA later */ 1491 set_bit(PC_DMA_IN_PROGRESS, &pc->flags); 1492 if (test_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags)) { 1493 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc, 1494 IDETAPE_WAIT_CMD, NULL); 1495 return ide_started; 1496 } else { 1497 hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG); 1498 return idetape_transfer_pc(drive); 1499 } 1500} 1501 1502/* 1503 * General packet command callback function. 1504 */ 1505static ide_startstop_t idetape_pc_callback (ide_drive_t *drive) 1506{ 1507 idetape_tape_t *tape = drive->driver_data; 1508 1509#if IDETAPE_DEBUG_LOG 1510 if (tape->debug_level >= 4) 1511 printk(KERN_INFO "ide-tape: Reached idetape_pc_callback\n"); 1512#endif /* IDETAPE_DEBUG_LOG */ 1513 1514 idetape_end_request(drive, tape->pc->error ? 0 : 1, 0); 1515 return ide_stopped; 1516} 1517 1518/* 1519 * A mode sense command is used to "sense" tape parameters. 1520 */ 1521static void idetape_create_mode_sense_cmd (idetape_pc_t *pc, u8 page_code) 1522{ 1523 idetape_init_pc(pc); 1524 pc->c[0] = MODE_SENSE; 1525 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 1526 pc->c[1] = 8; /* DBD = 1 - Don't return block descriptors */ 1527 pc->c[2] = page_code; 1528 /* 1529 * Changed pc->c[3] to 0 (255 will at best return unused info). 1530 * 1531 * For SCSI this byte is defined as subpage instead of high byte 1532 * of length and some IDE drives seem to interpret it this way 1533 * and return an error when 255 is used. 1534 */ 1535 pc->c[3] = 0; 1536 pc->c[4] = 255; /* (We will just discard data in that case) */ 1537 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 1538 pc->request_transfer = 12; 1539 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 1540 pc->request_transfer = 24; 1541 else 1542 pc->request_transfer = 50; 1543 pc->callback = &idetape_pc_callback; 1544} 1545 1546static void calculate_speeds(ide_drive_t *drive) 1547{ 1548 idetape_tape_t *tape = drive->driver_data; 1549 int full = 125, empty = 75; 1550 1551 if (time_after(jiffies, tape->controlled_pipeline_head_time + 120 * HZ)) { 1552 tape->controlled_previous_pipeline_head = tape->controlled_last_pipeline_head; 1553 tape->controlled_previous_head_time = tape->controlled_pipeline_head_time; 1554 tape->controlled_last_pipeline_head = tape->pipeline_head; 1555 tape->controlled_pipeline_head_time = jiffies; 1556 } 1557 if (time_after(jiffies, tape->controlled_pipeline_head_time + 60 * HZ)) 1558 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_last_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_pipeline_head_time); 1559 else if (time_after(jiffies, tape->controlled_previous_head_time)) 1560 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_previous_head_time); 1561 1562 if (tape->nr_pending_stages < tape->max_stages /*- 1 */) { 1563 /* -1 for read mode error recovery */ 1564 if (time_after(jiffies, tape->uncontrolled_previous_head_time + 10 * HZ)) { 1565 tape->uncontrolled_pipeline_head_time = jiffies; 1566 tape->uncontrolled_pipeline_head_speed = (tape->pipeline_head - tape->uncontrolled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->uncontrolled_previous_head_time); 1567 } 1568 } else { 1569 tape->uncontrolled_previous_head_time = jiffies; 1570 tape->uncontrolled_previous_pipeline_head = tape->pipeline_head; 1571 if (time_after(jiffies, tape->uncontrolled_pipeline_head_time + 30 * HZ)) { 1572 tape->uncontrolled_pipeline_head_time = jiffies; 1573 } 1574 } 1575 tape->pipeline_head_speed = max(tape->uncontrolled_pipeline_head_speed, tape->controlled_pipeline_head_speed); 1576 if (tape->speed_control == 0) { 1577 tape->max_insert_speed = 5000; 1578 } else if (tape->speed_control == 1) { 1579 if (tape->nr_pending_stages >= tape->max_stages / 2) 1580 tape->max_insert_speed = tape->pipeline_head_speed + 1581 (1100 - tape->pipeline_head_speed) * 2 * (tape->nr_pending_stages - tape->max_stages / 2) / tape->max_stages; 1582 else 1583 tape->max_insert_speed = 500 + 1584 (tape->pipeline_head_speed - 500) * 2 * tape->nr_pending_stages / tape->max_stages; 1585 if (tape->nr_pending_stages >= tape->max_stages * 99 / 100) 1586 tape->max_insert_speed = 5000; 1587 } else if (tape->speed_control == 2) { 1588 tape->max_insert_speed = tape->pipeline_head_speed * empty / 100 + 1589 (tape->pipeline_head_speed * full / 100 - tape->pipeline_head_speed * empty / 100) * tape->nr_pending_stages / tape->max_stages; 1590 } else 1591 tape->max_insert_speed = tape->speed_control; 1592 tape->max_insert_speed = max(tape->max_insert_speed, 500); 1593} 1594 1595static ide_startstop_t idetape_media_access_finished (ide_drive_t *drive) 1596{ 1597 idetape_tape_t *tape = drive->driver_data; 1598 idetape_pc_t *pc = tape->pc; 1599 u8 stat; 1600 1601 stat = ide_read_status(drive); 1602 1603 if (stat & SEEK_STAT) { 1604 if (stat & ERR_STAT) { 1605 /* Error detected */ 1606 if (pc->c[0] != TEST_UNIT_READY) 1607 printk(KERN_ERR "ide-tape: %s: I/O error, ", 1608 tape->name); 1609 /* Retry operation */ 1610 return idetape_retry_pc(drive); 1611 } 1612 pc->error = 0; 1613 if (tape->failed_pc == pc) 1614 tape->failed_pc = NULL; 1615 } else { 1616 pc->error = IDETAPE_ERROR_GENERAL; 1617 tape->failed_pc = NULL; 1618 } 1619 return pc->callback(drive); 1620} 1621 1622static ide_startstop_t idetape_rw_callback (ide_drive_t *drive) 1623{ 1624 idetape_tape_t *tape = drive->driver_data; 1625 struct request *rq = HWGROUP(drive)->rq; 1626 int blocks = tape->pc->actually_transferred / tape->tape_block_size; 1627 1628 tape->avg_size += blocks * tape->tape_block_size; 1629 tape->insert_size += blocks * tape->tape_block_size; 1630 if (tape->insert_size > 1024 * 1024) 1631 tape->measure_insert_time = 1; 1632 if (tape->measure_insert_time) { 1633 tape->measure_insert_time = 0; 1634 tape->insert_time = jiffies; 1635 tape->insert_size = 0; 1636 } 1637 if (time_after(jiffies, tape->insert_time)) 1638 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time); 1639 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 1640 tape->avg_speed = tape->avg_size * HZ / (jiffies - tape->avg_time) / 1024; 1641 tape->avg_size = 0; 1642 tape->avg_time = jiffies; 1643 } 1644 1645#if IDETAPE_DEBUG_LOG 1646 if (tape->debug_level >= 4) 1647 printk(KERN_INFO "ide-tape: Reached idetape_rw_callback\n"); 1648#endif /* IDETAPE_DEBUG_LOG */ 1649 1650 tape->first_frame_position += blocks; 1651 rq->current_nr_sectors -= blocks; 1652 1653 if (!tape->pc->error) 1654 idetape_end_request(drive, 1, 0); 1655 else 1656 idetape_end_request(drive, tape->pc->error, 0); 1657 return ide_stopped; 1658} 1659 1660static void idetape_create_read_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh) 1661{ 1662 idetape_init_pc(pc); 1663 pc->c[0] = READ_6; 1664 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1665 pc->c[1] = 1; 1666 pc->callback = &idetape_rw_callback; 1667 pc->bh = bh; 1668 atomic_set(&bh->b_count, 0); 1669 pc->buffer = NULL; 1670 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size; 1671 if (pc->request_transfer == tape->stage_size) 1672 set_bit(PC_DMA_RECOMMENDED, &pc->flags); 1673} 1674 1675static void idetape_create_read_buffer_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh) 1676{ 1677 int size = 32768; 1678 struct idetape_bh *p = bh; 1679 1680 idetape_init_pc(pc); 1681 pc->c[0] = READ_BUFFER; 1682 pc->c[1] = IDETAPE_RETRIEVE_FAULTY_BLOCK; 1683 pc->c[7] = size >> 8; 1684 pc->c[8] = size & 0xff; 1685 pc->callback = &idetape_pc_callback; 1686 pc->bh = bh; 1687 atomic_set(&bh->b_count, 0); 1688 pc->buffer = NULL; 1689 while (p) { 1690 atomic_set(&p->b_count, 0); 1691 p = p->b_reqnext; 1692 } 1693 pc->request_transfer = pc->buffer_size = size; 1694} 1695 1696static void idetape_create_write_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh) 1697{ 1698 idetape_init_pc(pc); 1699 pc->c[0] = WRITE_6; 1700 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1701 pc->c[1] = 1; 1702 pc->callback = &idetape_rw_callback; 1703 set_bit(PC_WRITING, &pc->flags); 1704 pc->bh = bh; 1705 pc->b_data = bh->b_data; 1706 pc->b_count = atomic_read(&bh->b_count); 1707 pc->buffer = NULL; 1708 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size; 1709 if (pc->request_transfer == tape->stage_size) 1710 set_bit(PC_DMA_RECOMMENDED, &pc->flags); 1711} 1712 1713/* 1714 * idetape_do_request is our request handling function. 1715 */ 1716static ide_startstop_t idetape_do_request(ide_drive_t *drive, 1717 struct request *rq, sector_t block) 1718{ 1719 idetape_tape_t *tape = drive->driver_data; 1720 idetape_pc_t *pc = NULL; 1721 struct request *postponed_rq = tape->postponed_rq; 1722 u8 stat; 1723 1724#if IDETAPE_DEBUG_LOG 1725 if (tape->debug_level >= 2) 1726 printk(KERN_INFO "ide-tape: sector: %ld, " 1727 "nr_sectors: %ld, current_nr_sectors: %d\n", 1728 rq->sector, rq->nr_sectors, rq->current_nr_sectors); 1729#endif /* IDETAPE_DEBUG_LOG */ 1730 1731 if (!blk_special_request(rq)) { 1732 /* 1733 * We do not support buffer cache originated requests. 1734 */ 1735 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 1736 "request queue (%d)\n", drive->name, rq->cmd_type); 1737 ide_end_request(drive, 0, 0); 1738 return ide_stopped; 1739 } 1740 1741 /* 1742 * Retry a failed packet command 1743 */ 1744 if (tape->failed_pc != NULL && 1745 tape->pc->c[0] == REQUEST_SENSE) { 1746 return idetape_issue_packet_command(drive, tape->failed_pc); 1747 } 1748 if (postponed_rq != NULL) 1749 if (rq != postponed_rq) { 1750 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 1751 "Two DSC requests were queued\n"); 1752 idetape_end_request(drive, 0, 0); 1753 return ide_stopped; 1754 } 1755 1756 tape->postponed_rq = NULL; 1757 1758 /* 1759 * If the tape is still busy, postpone our request and service 1760 * the other device meanwhile. 1761 */ 1762 stat = ide_read_status(drive); 1763 1764 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2)) 1765 set_bit(IDETAPE_IGNORE_DSC, &tape->flags); 1766 1767 if (drive->post_reset == 1) { 1768 set_bit(IDETAPE_IGNORE_DSC, &tape->flags); 1769 drive->post_reset = 0; 1770 } 1771 1772 if (tape->tape_still_time > 100 && tape->tape_still_time < 200) 1773 tape->measure_insert_time = 1; 1774 if (time_after(jiffies, tape->insert_time)) 1775 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time); 1776 calculate_speeds(drive); 1777 if (!test_and_clear_bit(IDETAPE_IGNORE_DSC, &tape->flags) && 1778 (stat & SEEK_STAT) == 0) { 1779 if (postponed_rq == NULL) { 1780 tape->dsc_polling_start = jiffies; 1781 tape->dsc_polling_frequency = tape->best_dsc_rw_frequency; 1782 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 1783 } else if (time_after(jiffies, tape->dsc_timeout)) { 1784 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 1785 tape->name); 1786 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1787 idetape_media_access_finished(drive); 1788 return ide_stopped; 1789 } else { 1790 return ide_do_reset(drive); 1791 } 1792 } else if (time_after(jiffies, tape->dsc_polling_start + IDETAPE_DSC_MA_THRESHOLD)) 1793 tape->dsc_polling_frequency = IDETAPE_DSC_MA_SLOW; 1794 idetape_postpone_request(drive); 1795 return ide_stopped; 1796 } 1797 if (rq->cmd[0] & REQ_IDETAPE_READ) { 1798 tape->buffer_head++; 1799 tape->postpone_cnt = 0; 1800 pc = idetape_next_pc_storage(drive); 1801 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special); 1802 goto out; 1803 } 1804 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 1805 tape->buffer_head++; 1806 tape->postpone_cnt = 0; 1807 pc = idetape_next_pc_storage(drive); 1808 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special); 1809 goto out; 1810 } 1811 if (rq->cmd[0] & REQ_IDETAPE_READ_BUFFER) { 1812 tape->postpone_cnt = 0; 1813 pc = idetape_next_pc_storage(drive); 1814 idetape_create_read_buffer_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special); 1815 goto out; 1816 } 1817 if (rq->cmd[0] & REQ_IDETAPE_PC1) { 1818 pc = (idetape_pc_t *) rq->buffer; 1819 rq->cmd[0] &= ~(REQ_IDETAPE_PC1); 1820 rq->cmd[0] |= REQ_IDETAPE_PC2; 1821 goto out; 1822 } 1823 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1824 idetape_media_access_finished(drive); 1825 return ide_stopped; 1826 } 1827 BUG(); 1828out: 1829 return idetape_issue_packet_command(drive, pc); 1830} 1831 1832/* 1833 * Pipeline related functions 1834 */ 1835static inline int idetape_pipeline_active (idetape_tape_t *tape) 1836{ 1837 int rc1, rc2; 1838 1839 rc1 = test_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags); 1840 rc2 = (tape->active_data_request != NULL); 1841 return rc1; 1842} 1843 1844/* 1845 * idetape_kmalloc_stage uses __get_free_page to allocate a pipeline 1846 * stage, along with all the necessary small buffers which together make 1847 * a buffer of size tape->stage_size (or a bit more). We attempt to 1848 * combine sequential pages as much as possible. 1849 * 1850 * Returns a pointer to the new allocated stage, or NULL if we 1851 * can't (or don't want to) allocate a stage. 1852 * 1853 * Pipeline stages are optional and are used to increase performance. 1854 * If we can't allocate them, we'll manage without them. 1855 */ 1856static idetape_stage_t *__idetape_kmalloc_stage (idetape_tape_t *tape, int full, int clear) 1857{ 1858 idetape_stage_t *stage; 1859 struct idetape_bh *prev_bh, *bh; 1860 int pages = tape->pages_per_stage; 1861 char *b_data = NULL; 1862 1863 if ((stage = kmalloc(sizeof (idetape_stage_t),GFP_KERNEL)) == NULL) 1864 return NULL; 1865 stage->next = NULL; 1866 1867 bh = stage->bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1868 if (bh == NULL) 1869 goto abort; 1870 bh->b_reqnext = NULL; 1871 if ((bh->b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL) 1872 goto abort; 1873 if (clear) 1874 memset(bh->b_data, 0, PAGE_SIZE); 1875 bh->b_size = PAGE_SIZE; 1876 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1877 1878 while (--pages) { 1879 if ((b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL) 1880 goto abort; 1881 if (clear) 1882 memset(b_data, 0, PAGE_SIZE); 1883 if (bh->b_data == b_data + PAGE_SIZE) { 1884 bh->b_size += PAGE_SIZE; 1885 bh->b_data -= PAGE_SIZE; 1886 if (full) 1887 atomic_add(PAGE_SIZE, &bh->b_count); 1888 continue; 1889 } 1890 if (b_data == bh->b_data + bh->b_size) { 1891 bh->b_size += PAGE_SIZE; 1892 if (full) 1893 atomic_add(PAGE_SIZE, &bh->b_count); 1894 continue; 1895 } 1896 prev_bh = bh; 1897 if ((bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL)) == NULL) { 1898 free_page((unsigned long) b_data); 1899 goto abort; 1900 } 1901 bh->b_reqnext = NULL; 1902 bh->b_data = b_data; 1903 bh->b_size = PAGE_SIZE; 1904 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1905 prev_bh->b_reqnext = bh; 1906 } 1907 bh->b_size -= tape->excess_bh_size; 1908 if (full) 1909 atomic_sub(tape->excess_bh_size, &bh->b_count); 1910 return stage; 1911abort: 1912 __idetape_kfree_stage(stage); 1913 return NULL; 1914} 1915 1916static idetape_stage_t *idetape_kmalloc_stage (idetape_tape_t *tape) 1917{ 1918 idetape_stage_t *cache_stage = tape->cache_stage; 1919 1920#if IDETAPE_DEBUG_LOG 1921 if (tape->debug_level >= 4) 1922 printk(KERN_INFO "ide-tape: Reached idetape_kmalloc_stage\n"); 1923#endif /* IDETAPE_DEBUG_LOG */ 1924 1925 if (tape->nr_stages >= tape->max_stages) 1926 return NULL; 1927 if (cache_stage != NULL) { 1928 tape->cache_stage = NULL; 1929 return cache_stage; 1930 } 1931 return __idetape_kmalloc_stage(tape, 0, 0); 1932} 1933 1934static int idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *stage, const char __user *buf, int n) 1935{ 1936 struct idetape_bh *bh = tape->bh; 1937 int count; 1938 int ret = 0; 1939 1940 while (n) { 1941 if (bh == NULL) { 1942 printk(KERN_ERR "ide-tape: bh == NULL in " 1943 "idetape_copy_stage_from_user\n"); 1944 return 1; 1945 } 1946 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), (unsigned int)n); 1947 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, count)) 1948 ret = 1; 1949 n -= count; 1950 atomic_add(count, &bh->b_count); 1951 buf += count; 1952 if (atomic_read(&bh->b_count) == bh->b_size) { 1953 bh = bh->b_reqnext; 1954 if (bh) 1955 atomic_set(&bh->b_count, 0); 1956 } 1957 } 1958 tape->bh = bh; 1959 return ret; 1960} 1961 1962static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, idetape_stage_t *stage, int n) 1963{ 1964 struct idetape_bh *bh = tape->bh; 1965 int count; 1966 int ret = 0; 1967 1968 while (n) { 1969 if (bh == NULL) { 1970 printk(KERN_ERR "ide-tape: bh == NULL in " 1971 "idetape_copy_stage_to_user\n"); 1972 return 1; 1973 } 1974 count = min(tape->b_count, n); 1975 if (copy_to_user(buf, tape->b_data, count)) 1976 ret = 1; 1977 n -= count; 1978 tape->b_data += count; 1979 tape->b_count -= count; 1980 buf += count; 1981 if (!tape->b_count) { 1982 tape->bh = bh = bh->b_reqnext; 1983 if (bh) { 1984 tape->b_data = bh->b_data; 1985 tape->b_count = atomic_read(&bh->b_count); 1986 } 1987 } 1988 } 1989 return ret; 1990} 1991 1992static void idetape_init_merge_stage (idetape_tape_t *tape) 1993{ 1994 struct idetape_bh *bh = tape->merge_stage->bh; 1995 1996 tape->bh = bh; 1997 if (tape->chrdev_direction == idetape_direction_write) 1998 atomic_set(&bh->b_count, 0); 1999 else { 2000 tape->b_data = bh->b_data; 2001 tape->b_count = atomic_read(&bh->b_count); 2002 } 2003} 2004 2005static void idetape_switch_buffers (idetape_tape_t *tape, idetape_stage_t *stage) 2006{ 2007 struct idetape_bh *tmp; 2008 2009 tmp = stage->bh; 2010 stage->bh = tape->merge_stage->bh; 2011 tape->merge_stage->bh = tmp; 2012 idetape_init_merge_stage(tape); 2013} 2014 2015/* 2016 * idetape_add_stage_tail adds a new stage at the end of the pipeline. 2017 */ 2018static void idetape_add_stage_tail (ide_drive_t *drive,idetape_stage_t *stage) 2019{ 2020 idetape_tape_t *tape = drive->driver_data; 2021 unsigned long flags; 2022 2023#if IDETAPE_DEBUG_LOG 2024 if (tape->debug_level >= 4) 2025 printk (KERN_INFO "ide-tape: Reached idetape_add_stage_tail\n"); 2026#endif /* IDETAPE_DEBUG_LOG */ 2027 spin_lock_irqsave(&tape->spinlock, flags); 2028 stage->next = NULL; 2029 if (tape->last_stage != NULL) 2030 tape->last_stage->next=stage; 2031 else 2032 tape->first_stage = tape->next_stage=stage; 2033 tape->last_stage = stage; 2034 if (tape->next_stage == NULL) 2035 tape->next_stage = tape->last_stage; 2036 tape->nr_stages++; 2037 tape->nr_pending_stages++; 2038 spin_unlock_irqrestore(&tape->spinlock, flags); 2039} 2040 2041/* 2042 * idetape_wait_for_request installs a completion in a pending request 2043 * and sleeps until it is serviced. 2044 * 2045 * The caller should ensure that the request will not be serviced 2046 * before we install the completion (usually by disabling interrupts). 2047 */ 2048static void idetape_wait_for_request (ide_drive_t *drive, struct request *rq) 2049{ 2050 DECLARE_COMPLETION_ONSTACK(wait); 2051 idetape_tape_t *tape = drive->driver_data; 2052 2053 if (rq == NULL || !blk_special_request(rq)) { 2054 printk (KERN_ERR "ide-tape: bug: Trying to sleep on non-valid request\n"); 2055 return; 2056 } 2057 rq->end_io_data = &wait; 2058 rq->end_io = blk_end_sync_rq; 2059 spin_unlock_irq(&tape->spinlock); 2060 wait_for_completion(&wait); 2061 /* The stage and its struct request have been deallocated */ 2062 spin_lock_irq(&tape->spinlock); 2063} 2064 2065static ide_startstop_t idetape_read_position_callback (ide_drive_t *drive) 2066{ 2067 idetape_tape_t *tape = drive->driver_data; 2068 idetape_read_position_result_t *result; 2069 2070#if IDETAPE_DEBUG_LOG 2071 if (tape->debug_level >= 4) 2072 printk(KERN_INFO "ide-tape: Reached idetape_read_position_callback\n"); 2073#endif /* IDETAPE_DEBUG_LOG */ 2074 2075 if (!tape->pc->error) { 2076 result = (idetape_read_position_result_t *) tape->pc->buffer; 2077#if IDETAPE_DEBUG_LOG 2078 if (tape->debug_level >= 2) 2079 printk(KERN_INFO "ide-tape: BOP - %s\n",result->bop ? "Yes":"No"); 2080 if (tape->debug_level >= 2) 2081 printk(KERN_INFO "ide-tape: EOP - %s\n",result->eop ? "Yes":"No"); 2082#endif /* IDETAPE_DEBUG_LOG */ 2083 if (result->bpu) { 2084 printk(KERN_INFO "ide-tape: Block location is unknown to the tape\n"); 2085 clear_bit(IDETAPE_ADDRESS_VALID, &tape->flags); 2086 idetape_end_request(drive, 0, 0); 2087 } else { 2088#if IDETAPE_DEBUG_LOG 2089 if (tape->debug_level >= 2) 2090 printk(KERN_INFO "ide-tape: Block Location - %u\n", ntohl(result->first_block)); 2091#endif /* IDETAPE_DEBUG_LOG */ 2092 tape->partition = result->partition; 2093 tape->first_frame_position = ntohl(result->first_block); 2094 tape->last_frame_position = ntohl(result->last_block); 2095 tape->blocks_in_buffer = result->blocks_in_buffer[2]; 2096 set_bit(IDETAPE_ADDRESS_VALID, &tape->flags); 2097 idetape_end_request(drive, 1, 0); 2098 } 2099 } else { 2100 idetape_end_request(drive, 0, 0); 2101 } 2102 return ide_stopped; 2103} 2104 2105/* 2106 * idetape_create_write_filemark_cmd will: 2107 * 2108 * 1. Write a filemark if write_filemark=1. 2109 * 2. Flush the device buffers without writing a filemark 2110 * if write_filemark=0. 2111 * 2112 */ 2113static void idetape_create_write_filemark_cmd (ide_drive_t *drive, idetape_pc_t *pc,int write_filemark) 2114{ 2115 idetape_init_pc(pc); 2116 pc->c[0] = WRITE_FILEMARKS; 2117 pc->c[4] = write_filemark; 2118 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2119 pc->callback = &idetape_pc_callback; 2120} 2121 2122static void idetape_create_test_unit_ready_cmd(idetape_pc_t *pc) 2123{ 2124 idetape_init_pc(pc); 2125 pc->c[0] = TEST_UNIT_READY; 2126 pc->callback = &idetape_pc_callback; 2127} 2128 2129/* 2130 * idetape_queue_pc_tail is based on the following functions: 2131 * 2132 * ide_do_drive_cmd from ide.c 2133 * cdrom_queue_request and cdrom_queue_packet_command from ide-cd.c 2134 * 2135 * We add a special packet command request to the tail of the request 2136 * queue, and wait for it to be serviced. 2137 * 2138 * This is not to be called from within the request handling part 2139 * of the driver ! We allocate here data in the stack, and it is valid 2140 * until the request is finished. This is not the case for the bottom 2141 * part of the driver, where we are always leaving the functions to wait 2142 * for an interrupt or a timer event. 2143 * 2144 * From the bottom part of the driver, we should allocate safe memory 2145 * using idetape_next_pc_storage and idetape_next_rq_storage, and add 2146 * the request to the request list without waiting for it to be serviced ! 2147 * In that case, we usually use idetape_queue_pc_head. 2148 */ 2149static int __idetape_queue_pc_tail (ide_drive_t *drive, idetape_pc_t *pc) 2150{ 2151 struct ide_tape_obj *tape = drive->driver_data; 2152 struct request rq; 2153 2154 idetape_init_rq(&rq, REQ_IDETAPE_PC1); 2155 rq.buffer = (char *) pc; 2156 rq.rq_disk = tape->disk; 2157 return ide_do_drive_cmd(drive, &rq, ide_wait); 2158} 2159 2160static void idetape_create_load_unload_cmd (ide_drive_t *drive, idetape_pc_t *pc,int cmd) 2161{ 2162 idetape_init_pc(pc); 2163 pc->c[0] = START_STOP; 2164 pc->c[4] = cmd; 2165 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2166 pc->callback = &idetape_pc_callback; 2167} 2168 2169static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 2170{ 2171 idetape_tape_t *tape = drive->driver_data; 2172 idetape_pc_t pc; 2173 int load_attempted = 0; 2174 2175 /* 2176 * Wait for the tape to become ready 2177 */ 2178 set_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags); 2179 timeout += jiffies; 2180 while (time_before(jiffies, timeout)) { 2181 idetape_create_test_unit_ready_cmd(&pc); 2182 if (!__idetape_queue_pc_tail(drive, &pc)) 2183 return 0; 2184 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 2185 || (tape->asc == 0x3A)) { /* no media */ 2186 if (load_attempted) 2187 return -ENOMEDIUM; 2188 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK); 2189 __idetape_queue_pc_tail(drive, &pc); 2190 load_attempted = 1; 2191 /* not about to be ready */ 2192 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 2193 (tape->ascq == 1 || tape->ascq == 8))) 2194 return -EIO; 2195 msleep(100); 2196 } 2197 return -EIO; 2198} 2199 2200static int idetape_queue_pc_tail (ide_drive_t *drive,idetape_pc_t *pc) 2201{ 2202 return __idetape_queue_pc_tail(drive, pc); 2203} 2204 2205static int idetape_flush_tape_buffers (ide_drive_t *drive) 2206{ 2207 idetape_pc_t pc; 2208 int rc; 2209 2210 idetape_create_write_filemark_cmd(drive, &pc, 0); 2211 if ((rc = idetape_queue_pc_tail(drive, &pc))) 2212 return rc; 2213 idetape_wait_ready(drive, 60 * 5 * HZ); 2214 return 0; 2215} 2216 2217static void idetape_create_read_position_cmd (idetape_pc_t *pc) 2218{ 2219 idetape_init_pc(pc); 2220 pc->c[0] = READ_POSITION; 2221 pc->request_transfer = 20; 2222 pc->callback = &idetape_read_position_callback; 2223} 2224 2225static int idetape_read_position (ide_drive_t *drive) 2226{ 2227 idetape_tape_t *tape = drive->driver_data; 2228 idetape_pc_t pc; 2229 int position; 2230 2231#if IDETAPE_DEBUG_LOG 2232 if (tape->debug_level >= 4) 2233 printk(KERN_INFO "ide-tape: Reached idetape_read_position\n"); 2234#endif /* IDETAPE_DEBUG_LOG */ 2235 2236 idetape_create_read_position_cmd(&pc); 2237 if (idetape_queue_pc_tail(drive, &pc)) 2238 return -1; 2239 position = tape->first_frame_position; 2240 return position; 2241} 2242 2243static void idetape_create_locate_cmd (ide_drive_t *drive, idetape_pc_t *pc, unsigned int block, u8 partition, int skip) 2244{ 2245 idetape_init_pc(pc); 2246 pc->c[0] = POSITION_TO_ELEMENT; 2247 pc->c[1] = 2; 2248 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 2249 pc->c[8] = partition; 2250 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2251 pc->callback = &idetape_pc_callback; 2252} 2253 2254static int idetape_create_prevent_cmd (ide_drive_t *drive, idetape_pc_t *pc, int prevent) 2255{ 2256 idetape_tape_t *tape = drive->driver_data; 2257 2258 /* device supports locking according to capabilities page */ 2259 if (!(tape->caps[6] & 0x01)) 2260 return 0; 2261 2262 idetape_init_pc(pc); 2263 pc->c[0] = ALLOW_MEDIUM_REMOVAL; 2264 pc->c[4] = prevent; 2265 pc->callback = &idetape_pc_callback; 2266 return 1; 2267} 2268 2269static int __idetape_discard_read_pipeline (ide_drive_t *drive) 2270{ 2271 idetape_tape_t *tape = drive->driver_data; 2272 unsigned long flags; 2273 int cnt; 2274 2275 if (tape->chrdev_direction != idetape_direction_read) 2276 return 0; 2277 2278 /* Remove merge stage. */ 2279 cnt = tape->merge_stage_size / tape->tape_block_size; 2280 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags)) 2281 ++cnt; /* Filemarks count as 1 sector */ 2282 tape->merge_stage_size = 0; 2283 if (tape->merge_stage != NULL) { 2284 __idetape_kfree_stage(tape->merge_stage); 2285 tape->merge_stage = NULL; 2286 } 2287 2288 /* Clear pipeline flags. */ 2289 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 2290 tape->chrdev_direction = idetape_direction_none; 2291 2292 /* Remove pipeline stages. */ 2293 if (tape->first_stage == NULL) 2294 return 0; 2295 2296 spin_lock_irqsave(&tape->spinlock, flags); 2297 tape->next_stage = NULL; 2298 if (idetape_pipeline_active(tape)) 2299 idetape_wait_for_request(drive, tape->active_data_request); 2300 spin_unlock_irqrestore(&tape->spinlock, flags); 2301 2302 while (tape->first_stage != NULL) { 2303 struct request *rq_ptr = &tape->first_stage->rq; 2304 2305 cnt += rq_ptr->nr_sectors - rq_ptr->current_nr_sectors; 2306 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK) 2307 ++cnt; 2308 idetape_remove_stage_head(drive); 2309 } 2310 tape->nr_pending_stages = 0; 2311 tape->max_stages = tape->min_pipeline; 2312 return cnt; 2313} 2314 2315/* 2316 * idetape_position_tape positions the tape to the requested block 2317 * using the LOCATE packet command. A READ POSITION command is then 2318 * issued to check where we are positioned. 2319 * 2320 * Like all higher level operations, we queue the commands at the tail 2321 * of the request queue and wait for their completion. 2322 * 2323 */ 2324static int idetape_position_tape (ide_drive_t *drive, unsigned int block, u8 partition, int skip) 2325{ 2326 idetape_tape_t *tape = drive->driver_data; 2327 int retval; 2328 idetape_pc_t pc; 2329 2330 if (tape->chrdev_direction == idetape_direction_read) 2331 __idetape_discard_read_pipeline(drive); 2332 idetape_wait_ready(drive, 60 * 5 * HZ); 2333 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 2334 retval = idetape_queue_pc_tail(drive, &pc); 2335 if (retval) 2336 return (retval); 2337 2338 idetape_create_read_position_cmd(&pc); 2339 return (idetape_queue_pc_tail(drive, &pc)); 2340} 2341 2342static void idetape_discard_read_pipeline (ide_drive_t *drive, int restore_position) 2343{ 2344 idetape_tape_t *tape = drive->driver_data; 2345 int cnt; 2346 int seek, position; 2347 2348 cnt = __idetape_discard_read_pipeline(drive); 2349 if (restore_position) { 2350 position = idetape_read_position(drive); 2351 seek = position > cnt ? position - cnt : 0; 2352 if (idetape_position_tape(drive, seek, 0, 0)) { 2353 printk(KERN_INFO "ide-tape: %s: position_tape failed in discard_pipeline()\n", tape->name); 2354 return; 2355 } 2356 } 2357} 2358 2359/* 2360 * idetape_queue_rw_tail generates a read/write request for the block 2361 * device interface and wait for it to be serviced. 2362 */ 2363static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, struct idetape_bh *bh) 2364{ 2365 idetape_tape_t *tape = drive->driver_data; 2366 struct request rq; 2367 2368#if IDETAPE_DEBUG_LOG 2369 if (tape->debug_level >= 2) 2370 printk(KERN_INFO "ide-tape: idetape_queue_rw_tail: cmd=%d\n",cmd); 2371#endif /* IDETAPE_DEBUG_LOG */ 2372 if (idetape_pipeline_active(tape)) { 2373 printk(KERN_ERR "ide-tape: bug: the pipeline is active in idetape_queue_rw_tail\n"); 2374 return (0); 2375 } 2376 2377 idetape_init_rq(&rq, cmd); 2378 rq.rq_disk = tape->disk; 2379 rq.special = (void *)bh; 2380 rq.sector = tape->first_frame_position; 2381 rq.nr_sectors = rq.current_nr_sectors = blocks; 2382 (void) ide_do_drive_cmd(drive, &rq, ide_wait); 2383 2384 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 2385 return 0; 2386 2387 if (tape->merge_stage) 2388 idetape_init_merge_stage(tape); 2389 if (rq.errors == IDETAPE_ERROR_GENERAL) 2390 return -EIO; 2391 return (tape->tape_block_size * (blocks-rq.current_nr_sectors)); 2392} 2393 2394/* 2395 * idetape_insert_pipeline_into_queue is used to start servicing the 2396 * pipeline stages, starting from tape->next_stage. 2397 */ 2398static void idetape_insert_pipeline_into_queue (ide_drive_t *drive) 2399{ 2400 idetape_tape_t *tape = drive->driver_data; 2401 2402 if (tape->next_stage == NULL) 2403 return; 2404 if (!idetape_pipeline_active(tape)) { 2405 set_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags); 2406 idetape_activate_next_stage(drive); 2407 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end); 2408 } 2409} 2410 2411static void idetape_create_inquiry_cmd (idetape_pc_t *pc) 2412{ 2413 idetape_init_pc(pc); 2414 pc->c[0] = INQUIRY; 2415 pc->c[4] = pc->request_transfer = 254; 2416 pc->callback = &idetape_pc_callback; 2417} 2418 2419static void idetape_create_rewind_cmd (ide_drive_t *drive, idetape_pc_t *pc) 2420{ 2421 idetape_init_pc(pc); 2422 pc->c[0] = REZERO_UNIT; 2423 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2424 pc->callback = &idetape_pc_callback; 2425} 2426 2427static void idetape_create_erase_cmd (idetape_pc_t *pc) 2428{ 2429 idetape_init_pc(pc); 2430 pc->c[0] = ERASE; 2431 pc->c[1] = 1; 2432 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2433 pc->callback = &idetape_pc_callback; 2434} 2435 2436static void idetape_create_space_cmd (idetape_pc_t *pc,int count, u8 cmd) 2437{ 2438 idetape_init_pc(pc); 2439 pc->c[0] = SPACE; 2440 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 2441 pc->c[1] = cmd; 2442 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2443 pc->callback = &idetape_pc_callback; 2444} 2445 2446static void idetape_wait_first_stage (ide_drive_t *drive) 2447{ 2448 idetape_tape_t *tape = drive->driver_data; 2449 unsigned long flags; 2450 2451 if (tape->first_stage == NULL) 2452 return; 2453 spin_lock_irqsave(&tape->spinlock, flags); 2454 if (tape->active_stage == tape->first_stage) 2455 idetape_wait_for_request(drive, tape->active_data_request); 2456 spin_unlock_irqrestore(&tape->spinlock, flags); 2457} 2458 2459/* 2460 * idetape_add_chrdev_write_request tries to add a character device 2461 * originated write request to our pipeline. In case we don't succeed, 2462 * we revert to non-pipelined operation mode for this request. 2463 * 2464 * 1. Try to allocate a new pipeline stage. 2465 * 2. If we can't, wait for more and more requests to be serviced 2466 * and try again each time. 2467 * 3. If we still can't allocate a stage, fallback to 2468 * non-pipelined operation mode for this request. 2469 */ 2470static int idetape_add_chrdev_write_request (ide_drive_t *drive, int blocks) 2471{ 2472 idetape_tape_t *tape = drive->driver_data; 2473 idetape_stage_t *new_stage; 2474 unsigned long flags; 2475 struct request *rq; 2476 2477#if IDETAPE_DEBUG_LOG 2478 if (tape->debug_level >= 3) 2479 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_write_request\n"); 2480#endif /* IDETAPE_DEBUG_LOG */ 2481 2482 /* 2483 * Attempt to allocate a new stage. 2484 * Pay special attention to possible race conditions. 2485 */ 2486 while ((new_stage = idetape_kmalloc_stage(tape)) == NULL) { 2487 spin_lock_irqsave(&tape->spinlock, flags); 2488 if (idetape_pipeline_active(tape)) { 2489 idetape_wait_for_request(drive, tape->active_data_request); 2490 spin_unlock_irqrestore(&tape->spinlock, flags); 2491 } else { 2492 spin_unlock_irqrestore(&tape->spinlock, flags); 2493 idetape_insert_pipeline_into_queue(drive); 2494 if (idetape_pipeline_active(tape)) 2495 continue; 2496 /* 2497 * Linux is short on memory. Fallback to 2498 * non-pipelined operation mode for this request. 2499 */ 2500 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh); 2501 } 2502 } 2503 rq = &new_stage->rq; 2504 idetape_init_rq(rq, REQ_IDETAPE_WRITE); 2505 /* Doesn't actually matter - We always assume sequential access */ 2506 rq->sector = tape->first_frame_position; 2507 rq->nr_sectors = rq->current_nr_sectors = blocks; 2508 2509 idetape_switch_buffers(tape, new_stage); 2510 idetape_add_stage_tail(drive, new_stage); 2511 tape->pipeline_head++; 2512 calculate_speeds(drive); 2513 2514 /* 2515 * Estimate whether the tape has stopped writing by checking 2516 * if our write pipeline is currently empty. If we are not 2517 * writing anymore, wait for the pipeline to be full enough 2518 * (90%) before starting to service requests, so that we will 2519 * be able to keep up with the higher speeds of the tape. 2520 */ 2521 if (!idetape_pipeline_active(tape)) { 2522 if (tape->nr_stages >= tape->max_stages * 9 / 10 || 2523 tape->nr_stages >= tape->max_stages - tape->uncontrolled_pipeline_head_speed * 3 * 1024 / tape->tape_block_size) { 2524 tape->measure_insert_time = 1; 2525 tape->insert_time = jiffies; 2526 tape->insert_size = 0; 2527 tape->insert_speed = 0; 2528 idetape_insert_pipeline_into_queue(drive); 2529 } 2530 } 2531 if (test_and_clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags)) 2532 /* Return a deferred error */ 2533 return -EIO; 2534 return blocks; 2535} 2536 2537/* 2538 * idetape_wait_for_pipeline will wait until all pending pipeline 2539 * requests are serviced. Typically called on device close. 2540 */ 2541static void idetape_wait_for_pipeline (ide_drive_t *drive) 2542{ 2543 idetape_tape_t *tape = drive->driver_data; 2544 unsigned long flags; 2545 2546 while (tape->next_stage || idetape_pipeline_active(tape)) { 2547 idetape_insert_pipeline_into_queue(drive); 2548 spin_lock_irqsave(&tape->spinlock, flags); 2549 if (idetape_pipeline_active(tape)) 2550 idetape_wait_for_request(drive, tape->active_data_request); 2551 spin_unlock_irqrestore(&tape->spinlock, flags); 2552 } 2553} 2554 2555static void idetape_empty_write_pipeline (ide_drive_t *drive) 2556{ 2557 idetape_tape_t *tape = drive->driver_data; 2558 int blocks, min; 2559 struct idetape_bh *bh; 2560 2561 if (tape->chrdev_direction != idetape_direction_write) { 2562 printk(KERN_ERR "ide-tape: bug: Trying to empty write pipeline, but we are not writing.\n"); 2563 return; 2564 } 2565 if (tape->merge_stage_size > tape->stage_size) { 2566 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 2567 tape->merge_stage_size = tape->stage_size; 2568 } 2569 if (tape->merge_stage_size) { 2570 blocks = tape->merge_stage_size / tape->tape_block_size; 2571 if (tape->merge_stage_size % tape->tape_block_size) { 2572 unsigned int i; 2573 2574 blocks++; 2575 i = tape->tape_block_size - tape->merge_stage_size % tape->tape_block_size; 2576 bh = tape->bh->b_reqnext; 2577 while (bh) { 2578 atomic_set(&bh->b_count, 0); 2579 bh = bh->b_reqnext; 2580 } 2581 bh = tape->bh; 2582 while (i) { 2583 if (bh == NULL) { 2584 2585 printk(KERN_INFO "ide-tape: bug, bh NULL\n"); 2586 break; 2587 } 2588 min = min(i, (unsigned int)(bh->b_size - atomic_read(&bh->b_count))); 2589 memset(bh->b_data + atomic_read(&bh->b_count), 0, min); 2590 atomic_add(min, &bh->b_count); 2591 i -= min; 2592 bh = bh->b_reqnext; 2593 } 2594 } 2595 (void) idetape_add_chrdev_write_request(drive, blocks); 2596 tape->merge_stage_size = 0; 2597 } 2598 idetape_wait_for_pipeline(drive); 2599 if (tape->merge_stage != NULL) { 2600 __idetape_kfree_stage(tape->merge_stage); 2601 tape->merge_stage = NULL; 2602 } 2603 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 2604 tape->chrdev_direction = idetape_direction_none; 2605 2606 /* 2607 * On the next backup, perform the feedback loop again. 2608 * (I don't want to keep sense information between backups, 2609 * as some systems are constantly on, and the system load 2610 * can be totally different on the next backup). 2611 */ 2612 tape->max_stages = tape->min_pipeline; 2613 if (tape->first_stage != NULL || 2614 tape->next_stage != NULL || 2615 tape->last_stage != NULL || 2616 tape->nr_stages != 0) { 2617 printk(KERN_ERR "ide-tape: ide-tape pipeline bug, " 2618 "first_stage %p, next_stage %p, " 2619 "last_stage %p, nr_stages %d\n", 2620 tape->first_stage, tape->next_stage, 2621 tape->last_stage, tape->nr_stages); 2622 } 2623} 2624 2625static void idetape_restart_speed_control (ide_drive_t *drive) 2626{ 2627 idetape_tape_t *tape = drive->driver_data; 2628 2629 tape->restart_speed_control_req = 0; 2630 tape->pipeline_head = 0; 2631 tape->controlled_last_pipeline_head = tape->uncontrolled_last_pipeline_head = 0; 2632 tape->controlled_previous_pipeline_head = tape->uncontrolled_previous_pipeline_head = 0; 2633 tape->pipeline_head_speed = tape->controlled_pipeline_head_speed = 5000; 2634 tape->uncontrolled_pipeline_head_speed = 0; 2635 tape->controlled_pipeline_head_time = tape->uncontrolled_pipeline_head_time = jiffies; 2636 tape->controlled_previous_head_time = tape->uncontrolled_previous_head_time = jiffies; 2637} 2638 2639static int idetape_initiate_read (ide_drive_t *drive, int max_stages) 2640{ 2641 idetape_tape_t *tape = drive->driver_data; 2642 idetape_stage_t *new_stage; 2643 struct request rq; 2644 int bytes_read; 2645 u16 blocks = *(u16 *)&tape->caps[12]; 2646 2647 /* Initialize read operation */ 2648 if (tape->chrdev_direction != idetape_direction_read) { 2649 if (tape->chrdev_direction == idetape_direction_write) { 2650 idetape_empty_write_pipeline(drive); 2651 idetape_flush_tape_buffers(drive); 2652 } 2653 if (tape->merge_stage || tape->merge_stage_size) { 2654 printk (KERN_ERR "ide-tape: merge_stage_size should be 0 now\n"); 2655 tape->merge_stage_size = 0; 2656 } 2657 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL) 2658 return -ENOMEM; 2659 tape->chrdev_direction = idetape_direction_read; 2660 2661 /* 2662 * Issue a read 0 command to ensure that DSC handshake 2663 * is switched from completion mode to buffer available 2664 * mode. 2665 * No point in issuing this if DSC overlap isn't supported, 2666 * some drives (Seagate STT3401A) will return an error. 2667 */ 2668 if (drive->dsc_overlap) { 2669 bytes_read = idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, 0, tape->merge_stage->bh); 2670 if (bytes_read < 0) { 2671 __idetape_kfree_stage(tape->merge_stage); 2672 tape->merge_stage = NULL; 2673 tape->chrdev_direction = idetape_direction_none; 2674 return bytes_read; 2675 } 2676 } 2677 } 2678 if (tape->restart_speed_control_req) 2679 idetape_restart_speed_control(drive); 2680 idetape_init_rq(&rq, REQ_IDETAPE_READ); 2681 rq.sector = tape->first_frame_position; 2682 rq.nr_sectors = rq.current_nr_sectors = blocks; 2683 if (!test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags) && 2684 tape->nr_stages < max_stages) { 2685 new_stage = idetape_kmalloc_stage(tape); 2686 while (new_stage != NULL) { 2687 new_stage->rq = rq; 2688 idetape_add_stage_tail(drive, new_stage); 2689 if (tape->nr_stages >= max_stages) 2690 break; 2691 new_stage = idetape_kmalloc_stage(tape); 2692 } 2693 } 2694 if (!idetape_pipeline_active(tape)) { 2695 if (tape->nr_pending_stages >= 3 * max_stages / 4) { 2696 tape->measure_insert_time = 1; 2697 tape->insert_time = jiffies; 2698 tape->insert_size = 0; 2699 tape->insert_speed = 0; 2700 idetape_insert_pipeline_into_queue(drive); 2701 } 2702 } 2703 return 0; 2704} 2705 2706/* 2707 * idetape_add_chrdev_read_request is called from idetape_chrdev_read 2708 * to service a character device read request and add read-ahead 2709 * requests to our pipeline. 2710 */ 2711static int idetape_add_chrdev_read_request (ide_drive_t *drive,int blocks) 2712{ 2713 idetape_tape_t *tape = drive->driver_data; 2714 unsigned long flags; 2715 struct request *rq_ptr; 2716 int bytes_read; 2717 2718#if IDETAPE_DEBUG_LOG 2719 if (tape->debug_level >= 4) 2720 printk(KERN_INFO "ide-tape: Reached idetape_add_chrdev_read_request, %d blocks\n", blocks); 2721#endif /* IDETAPE_DEBUG_LOG */ 2722 2723 /* 2724 * If we are at a filemark, return a read length of 0 2725 */ 2726 if (test_bit(IDETAPE_FILEMARK, &tape->flags)) 2727 return 0; 2728 2729 /* 2730 * Wait for the next block to be available at the head 2731 * of the pipeline 2732 */ 2733 idetape_initiate_read(drive, tape->max_stages); 2734 if (tape->first_stage == NULL) { 2735 if (test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags)) 2736 return 0; 2737 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, tape->merge_stage->bh); 2738 } 2739 idetape_wait_first_stage(drive); 2740 rq_ptr = &tape->first_stage->rq; 2741 bytes_read = tape->tape_block_size * (rq_ptr->nr_sectors - rq_ptr->current_nr_sectors); 2742 rq_ptr->nr_sectors = rq_ptr->current_nr_sectors = 0; 2743 2744 2745 if (rq_ptr->errors == IDETAPE_ERROR_EOD) 2746 return 0; 2747 else { 2748 idetape_switch_buffers(tape, tape->first_stage); 2749 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK) 2750 set_bit(IDETAPE_FILEMARK, &tape->flags); 2751 spin_lock_irqsave(&tape->spinlock, flags); 2752 idetape_remove_stage_head(drive); 2753 spin_unlock_irqrestore(&tape->spinlock, flags); 2754 tape->pipeline_head++; 2755 calculate_speeds(drive); 2756 } 2757 if (bytes_read > blocks * tape->tape_block_size) { 2758 printk(KERN_ERR "ide-tape: bug: trying to return more bytes than requested\n"); 2759 bytes_read = blocks * tape->tape_block_size; 2760 } 2761 return (bytes_read); 2762} 2763 2764static void idetape_pad_zeros (ide_drive_t *drive, int bcount) 2765{ 2766 idetape_tape_t *tape = drive->driver_data; 2767 struct idetape_bh *bh; 2768 int blocks; 2769 2770 while (bcount) { 2771 unsigned int count; 2772 2773 bh = tape->merge_stage->bh; 2774 count = min(tape->stage_size, bcount); 2775 bcount -= count; 2776 blocks = count / tape->tape_block_size; 2777 while (count) { 2778 atomic_set(&bh->b_count, min(count, (unsigned int)bh->b_size)); 2779 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 2780 count -= atomic_read(&bh->b_count); 2781 bh = bh->b_reqnext; 2782 } 2783 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh); 2784 } 2785} 2786 2787static int idetape_pipeline_size (ide_drive_t *drive) 2788{ 2789 idetape_tape_t *tape = drive->driver_data; 2790 idetape_stage_t *stage; 2791 struct request *rq; 2792 int size = 0; 2793 2794 idetape_wait_for_pipeline(drive); 2795 stage = tape->first_stage; 2796 while (stage != NULL) { 2797 rq = &stage->rq; 2798 size += tape->tape_block_size * (rq->nr_sectors-rq->current_nr_sectors); 2799 if (rq->errors == IDETAPE_ERROR_FILEMARK) 2800 size += tape->tape_block_size; 2801 stage = stage->next; 2802 } 2803 size += tape->merge_stage_size; 2804 return size; 2805} 2806 2807/* 2808 * Rewinds the tape to the Beginning Of the current Partition (BOP). 2809 * 2810 * We currently support only one partition. 2811 */ 2812static int idetape_rewind_tape (ide_drive_t *drive) 2813{ 2814 int retval; 2815 idetape_pc_t pc; 2816#if IDETAPE_DEBUG_LOG 2817 idetape_tape_t *tape = drive->driver_data; 2818 if (tape->debug_level >= 2) 2819 printk(KERN_INFO "ide-tape: Reached idetape_rewind_tape\n"); 2820#endif /* IDETAPE_DEBUG_LOG */ 2821 2822 idetape_create_rewind_cmd(drive, &pc); 2823 retval = idetape_queue_pc_tail(drive, &pc); 2824 if (retval) 2825 return retval; 2826 2827 idetape_create_read_position_cmd(&pc); 2828 retval = idetape_queue_pc_tail(drive, &pc); 2829 if (retval) 2830 return retval; 2831 return 0; 2832} 2833 2834/* 2835 * Our special ide-tape ioctl's. 2836 * 2837 * Currently there aren't any ioctl's. 2838 * mtio.h compatible commands should be issued to the character device 2839 * interface. 2840 */ 2841static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, unsigned long arg) 2842{ 2843 idetape_tape_t *tape = drive->driver_data; 2844 void __user *argp = (void __user *)arg; 2845 2846 struct idetape_config { 2847 int dsc_rw_frequency; 2848 int dsc_media_access_frequency; 2849 int nr_stages; 2850 } config; 2851 2852#if IDETAPE_DEBUG_LOG 2853 if (tape->debug_level >= 4) 2854 printk(KERN_INFO "ide-tape: Reached idetape_blkdev_ioctl\n"); 2855#endif /* IDETAPE_DEBUG_LOG */ 2856 switch (cmd) { 2857 case 0x0340: 2858 if (copy_from_user(&config, argp, sizeof(config))) 2859 return -EFAULT; 2860 tape->best_dsc_rw_frequency = config.dsc_rw_frequency; 2861 tape->max_stages = config.nr_stages; 2862 break; 2863 case 0x0350: 2864 config.dsc_rw_frequency = (int) tape->best_dsc_rw_frequency; 2865 config.nr_stages = tape->max_stages; 2866 if (copy_to_user(argp, &config, sizeof(config))) 2867 return -EFAULT; 2868 break; 2869 default: 2870 return -EIO; 2871 } 2872 return 0; 2873} 2874 2875/* 2876 * idetape_space_over_filemarks is now a bit more complicated than just 2877 * passing the command to the tape since we may have crossed some 2878 * filemarks during our pipelined read-ahead mode. 2879 * 2880 * As a minor side effect, the pipeline enables us to support MTFSFM when 2881 * the filemark is in our internal pipeline even if the tape doesn't 2882 * support spacing over filemarks in the reverse direction. 2883 */ 2884static int idetape_space_over_filemarks (ide_drive_t *drive,short mt_op,int mt_count) 2885{ 2886 idetape_tape_t *tape = drive->driver_data; 2887 idetape_pc_t pc; 2888 unsigned long flags; 2889 int retval,count=0; 2890 int sprev = !!(tape->caps[4] & 0x20); 2891 2892 if (mt_count == 0) 2893 return 0; 2894 if (MTBSF == mt_op || MTBSFM == mt_op) { 2895 if (!sprev) 2896 return -EIO; 2897 mt_count = - mt_count; 2898 } 2899 2900 if (tape->chrdev_direction == idetape_direction_read) { 2901 /* 2902 * We have a read-ahead buffer. Scan it for crossed 2903 * filemarks. 2904 */ 2905 tape->merge_stage_size = 0; 2906 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags)) 2907 ++count; 2908 while (tape->first_stage != NULL) { 2909 if (count == mt_count) { 2910 if (mt_op == MTFSFM) 2911 set_bit(IDETAPE_FILEMARK, &tape->flags); 2912 return 0; 2913 } 2914 spin_lock_irqsave(&tape->spinlock, flags); 2915 if (tape->first_stage == tape->active_stage) { 2916 /* 2917 * We have reached the active stage in the read pipeline. 2918 * There is no point in allowing the drive to continue 2919 * reading any farther, so we stop the pipeline. 2920 * 2921 * This section should be moved to a separate subroutine, 2922 * because a similar function is performed in 2923 * __idetape_discard_read_pipeline(), for example. 2924 */ 2925 tape->next_stage = NULL; 2926 spin_unlock_irqrestore(&tape->spinlock, flags); 2927 idetape_wait_first_stage(drive); 2928 tape->next_stage = tape->first_stage->next; 2929 } else 2930 spin_unlock_irqrestore(&tape->spinlock, flags); 2931 if (tape->first_stage->rq.errors == IDETAPE_ERROR_FILEMARK) 2932 ++count; 2933 idetape_remove_stage_head(drive); 2934 } 2935 idetape_discard_read_pipeline(drive, 0); 2936 } 2937 2938 /* 2939 * The filemark was not found in our internal pipeline. 2940 * Now we can issue the space command. 2941 */ 2942 switch (mt_op) { 2943 case MTFSF: 2944 case MTBSF: 2945 idetape_create_space_cmd(&pc,mt_count-count,IDETAPE_SPACE_OVER_FILEMARK); 2946 return (idetape_queue_pc_tail(drive, &pc)); 2947 case MTFSFM: 2948 case MTBSFM: 2949 if (!sprev) 2950 return (-EIO); 2951 retval = idetape_space_over_filemarks(drive, MTFSF, mt_count-count); 2952 if (retval) return (retval); 2953 count = (MTBSFM == mt_op ? 1 : -1); 2954 return (idetape_space_over_filemarks(drive, MTFSF, count)); 2955 default: 2956 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",mt_op); 2957 return (-EIO); 2958 } 2959} 2960 2961 2962/* 2963 * Our character device read / write functions. 2964 * 2965 * The tape is optimized to maximize throughput when it is transferring 2966 * an integral number of the "continuous transfer limit", which is 2967 * a parameter of the specific tape (26 KB on my particular tape). 2968 * (32 kB for Onstream) 2969 * 2970 * As of version 1.3 of the driver, the character device provides an 2971 * abstract continuous view of the media - any mix of block sizes (even 1 2972 * byte) on the same backup/restore procedure is supported. The driver 2973 * will internally convert the requests to the recommended transfer unit, 2974 * so that an unmatch between the user's block size to the recommended 2975 * size will only result in a (slightly) increased driver overhead, but 2976 * will no longer hit performance. 2977 * This is not applicable to Onstream. 2978 */ 2979static ssize_t idetape_chrdev_read (struct file *file, char __user *buf, 2980 size_t count, loff_t *ppos) 2981{ 2982 struct ide_tape_obj *tape = ide_tape_f(file); 2983 ide_drive_t *drive = tape->drive; 2984 ssize_t bytes_read,temp, actually_read = 0, rc; 2985 ssize_t ret = 0; 2986 u16 ctl = *(u16 *)&tape->caps[12]; 2987 2988#if IDETAPE_DEBUG_LOG 2989 if (tape->debug_level >= 3) 2990 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_read, count %Zd\n", count); 2991#endif /* IDETAPE_DEBUG_LOG */ 2992 2993 if (tape->chrdev_direction != idetape_direction_read) { 2994 if (test_bit(IDETAPE_DETECT_BS, &tape->flags)) 2995 if (count > tape->tape_block_size && 2996 (count % tape->tape_block_size) == 0) 2997 tape->user_bs_factor = count / tape->tape_block_size; 2998 } 2999 if ((rc = idetape_initiate_read(drive, tape->max_stages)) < 0) 3000 return rc; 3001 if (count == 0) 3002 return (0); 3003 if (tape->merge_stage_size) { 3004 actually_read = min((unsigned int)(tape->merge_stage_size), (unsigned int)count); 3005 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, actually_read)) 3006 ret = -EFAULT; 3007 buf += actually_read; 3008 tape->merge_stage_size -= actually_read; 3009 count -= actually_read; 3010 } 3011 while (count >= tape->stage_size) { 3012 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 3013 if (bytes_read <= 0) 3014 goto finish; 3015 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, bytes_read)) 3016 ret = -EFAULT; 3017 buf += bytes_read; 3018 count -= bytes_read; 3019 actually_read += bytes_read; 3020 } 3021 if (count) { 3022 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 3023 if (bytes_read <= 0) 3024 goto finish; 3025 temp = min((unsigned long)count, (unsigned long)bytes_read); 3026 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, temp)) 3027 ret = -EFAULT; 3028 actually_read += temp; 3029 tape->merge_stage_size = bytes_read-temp; 3030 } 3031finish: 3032 if (!actually_read && test_bit(IDETAPE_FILEMARK, &tape->flags)) { 3033#if IDETAPE_DEBUG_LOG 3034 if (tape->debug_level >= 2) 3035 printk(KERN_INFO "ide-tape: %s: spacing over filemark\n", tape->name); 3036#endif 3037 idetape_space_over_filemarks(drive, MTFSF, 1); 3038 return 0; 3039 } 3040 3041 return (ret) ? ret : actually_read; 3042} 3043 3044static ssize_t idetape_chrdev_write (struct file *file, const char __user *buf, 3045 size_t count, loff_t *ppos) 3046{ 3047 struct ide_tape_obj *tape = ide_tape_f(file); 3048 ide_drive_t *drive = tape->drive; 3049 ssize_t actually_written = 0; 3050 ssize_t ret = 0; 3051 u16 ctl = *(u16 *)&tape->caps[12]; 3052 3053 /* The drive is write protected. */ 3054 if (tape->write_prot) 3055 return -EACCES; 3056 3057#if IDETAPE_DEBUG_LOG 3058 if (tape->debug_level >= 3) 3059 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_write, " 3060 "count %Zd\n", count); 3061#endif /* IDETAPE_DEBUG_LOG */ 3062 3063 /* Initialize write operation */ 3064 if (tape->chrdev_direction != idetape_direction_write) { 3065 if (tape->chrdev_direction == idetape_direction_read) 3066 idetape_discard_read_pipeline(drive, 1); 3067 if (tape->merge_stage || tape->merge_stage_size) { 3068 printk(KERN_ERR "ide-tape: merge_stage_size " 3069 "should be 0 now\n"); 3070 tape->merge_stage_size = 0; 3071 } 3072 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL) 3073 return -ENOMEM; 3074 tape->chrdev_direction = idetape_direction_write; 3075 idetape_init_merge_stage(tape); 3076 3077 /* 3078 * Issue a write 0 command to ensure that DSC handshake 3079 * is switched from completion mode to buffer available 3080 * mode. 3081 * No point in issuing this if DSC overlap isn't supported, 3082 * some drives (Seagate STT3401A) will return an error. 3083 */ 3084 if (drive->dsc_overlap) { 3085 ssize_t retval = idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 0, tape->merge_stage->bh); 3086 if (retval < 0) { 3087 __idetape_kfree_stage(tape->merge_stage); 3088 tape->merge_stage = NULL; 3089 tape->chrdev_direction = idetape_direction_none; 3090 return retval; 3091 } 3092 } 3093 } 3094 if (count == 0) 3095 return (0); 3096 if (tape->restart_speed_control_req) 3097 idetape_restart_speed_control(drive); 3098 if (tape->merge_stage_size) { 3099 if (tape->merge_stage_size >= tape->stage_size) { 3100 printk(KERN_ERR "ide-tape: bug: merge buffer too big\n"); 3101 tape->merge_stage_size = 0; 3102 } 3103 actually_written = min((unsigned int)(tape->stage_size - tape->merge_stage_size), (unsigned int)count); 3104 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, actually_written)) 3105 ret = -EFAULT; 3106 buf += actually_written; 3107 tape->merge_stage_size += actually_written; 3108 count -= actually_written; 3109 3110 if (tape->merge_stage_size == tape->stage_size) { 3111 ssize_t retval; 3112 tape->merge_stage_size = 0; 3113 retval = idetape_add_chrdev_write_request(drive, ctl); 3114 if (retval <= 0) 3115 return (retval); 3116 } 3117 } 3118 while (count >= tape->stage_size) { 3119 ssize_t retval; 3120 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, tape->stage_size)) 3121 ret = -EFAULT; 3122 buf += tape->stage_size; 3123 count -= tape->stage_size; 3124 retval = idetape_add_chrdev_write_request(drive, ctl); 3125 actually_written += tape->stage_size; 3126 if (retval <= 0) 3127 return (retval); 3128 } 3129 if (count) { 3130 actually_written += count; 3131 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, count)) 3132 ret = -EFAULT; 3133 tape->merge_stage_size += count; 3134 } 3135 return (ret) ? ret : actually_written; 3136} 3137 3138static int idetape_write_filemark (ide_drive_t *drive) 3139{ 3140 idetape_pc_t pc; 3141 3142 /* Write a filemark */ 3143 idetape_create_write_filemark_cmd(drive, &pc, 1); 3144 if (idetape_queue_pc_tail(drive, &pc)) { 3145 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 3146 return -EIO; 3147 } 3148 return 0; 3149} 3150 3151/* 3152 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 3153 * requested. 3154 * 3155 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 3156 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 3157 * usually not supported (it is supported in the rare case in which we crossed 3158 * the filemark during our read-ahead pipelined operation mode). 3159 * 3160 * The following commands are currently not supported: 3161 * 3162 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 3163 * MT_ST_WRITE_THRESHOLD. 3164 */ 3165static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 3166{ 3167 idetape_tape_t *tape = drive->driver_data; 3168 idetape_pc_t pc; 3169 int i,retval; 3170 3171#if IDETAPE_DEBUG_LOG 3172 if (tape->debug_level >= 1) 3173 printk(KERN_INFO "ide-tape: Handling MTIOCTOP ioctl: " 3174 "mt_op=%d, mt_count=%d\n", mt_op, mt_count); 3175#endif /* IDETAPE_DEBUG_LOG */ 3176 /* 3177 * Commands which need our pipelined read-ahead stages. 3178 */ 3179 switch (mt_op) { 3180 case MTFSF: 3181 case MTFSFM: 3182 case MTBSF: 3183 case MTBSFM: 3184 if (!mt_count) 3185 return (0); 3186 return (idetape_space_over_filemarks(drive,mt_op,mt_count)); 3187 default: 3188 break; 3189 } 3190 switch (mt_op) { 3191 case MTWEOF: 3192 if (tape->write_prot) 3193 return -EACCES; 3194 idetape_discard_read_pipeline(drive, 1); 3195 for (i = 0; i < mt_count; i++) { 3196 retval = idetape_write_filemark(drive); 3197 if (retval) 3198 return retval; 3199 } 3200 return (0); 3201 case MTREW: 3202 idetape_discard_read_pipeline(drive, 0); 3203 if (idetape_rewind_tape(drive)) 3204 return -EIO; 3205 return 0; 3206 case MTLOAD: 3207 idetape_discard_read_pipeline(drive, 0); 3208 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK); 3209 return (idetape_queue_pc_tail(drive, &pc)); 3210 case MTUNLOAD: 3211 case MTOFFL: 3212 /* 3213 * If door is locked, attempt to unlock before 3214 * attempting to eject. 3215 */ 3216 if (tape->door_locked) { 3217 if (idetape_create_prevent_cmd(drive, &pc, 0)) 3218 if (!idetape_queue_pc_tail(drive, &pc)) 3219 tape->door_locked = DOOR_UNLOCKED; 3220 } 3221 idetape_discard_read_pipeline(drive, 0); 3222 idetape_create_load_unload_cmd(drive, &pc,!IDETAPE_LU_LOAD_MASK); 3223 retval = idetape_queue_pc_tail(drive, &pc); 3224 if (!retval) 3225 clear_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags); 3226 return retval; 3227 case MTNOP: 3228 idetape_discard_read_pipeline(drive, 0); 3229 return (idetape_flush_tape_buffers(drive)); 3230 case MTRETEN: 3231 idetape_discard_read_pipeline(drive, 0); 3232 idetape_create_load_unload_cmd(drive, &pc,IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 3233 return (idetape_queue_pc_tail(drive, &pc)); 3234 case MTEOM: 3235 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 3236 return (idetape_queue_pc_tail(drive, &pc)); 3237 case MTERASE: 3238 (void) idetape_rewind_tape(drive); 3239 idetape_create_erase_cmd(&pc); 3240 return (idetape_queue_pc_tail(drive, &pc)); 3241 case MTSETBLK: 3242 if (mt_count) { 3243 if (mt_count < tape->tape_block_size || mt_count % tape->tape_block_size) 3244 return -EIO; 3245 tape->user_bs_factor = mt_count / tape->tape_block_size; 3246 clear_bit(IDETAPE_DETECT_BS, &tape->flags); 3247 } else 3248 set_bit(IDETAPE_DETECT_BS, &tape->flags); 3249 return 0; 3250 case MTSEEK: 3251 idetape_discard_read_pipeline(drive, 0); 3252 return idetape_position_tape(drive, mt_count * tape->user_bs_factor, tape->partition, 0); 3253 case MTSETPART: 3254 idetape_discard_read_pipeline(drive, 0); 3255 return (idetape_position_tape(drive, 0, mt_count, 0)); 3256 case MTFSR: 3257 case MTBSR: 3258 case MTLOCK: 3259 if (!idetape_create_prevent_cmd(drive, &pc, 1)) 3260 return 0; 3261 retval = idetape_queue_pc_tail(drive, &pc); 3262 if (retval) return retval; 3263 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 3264 return 0; 3265 case MTUNLOCK: 3266 if (!idetape_create_prevent_cmd(drive, &pc, 0)) 3267 return 0; 3268 retval = idetape_queue_pc_tail(drive, &pc); 3269 if (retval) return retval; 3270 tape->door_locked = DOOR_UNLOCKED; 3271 return 0; 3272 default: 3273 printk(KERN_ERR "ide-tape: MTIO operation %d not " 3274 "supported\n", mt_op); 3275 return (-EIO); 3276 } 3277} 3278 3279/* 3280 * Our character device ioctls. General mtio.h magnetic io commands are 3281 * supported here, and not in the corresponding block interface. Our own 3282 * ide-tape ioctls are supported on both interfaces. 3283 */ 3284static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 3285 unsigned int cmd, unsigned long arg) 3286{ 3287 struct ide_tape_obj *tape = ide_tape_f(file); 3288 ide_drive_t *drive = tape->drive; 3289 struct mtop mtop; 3290 struct mtget mtget; 3291 struct mtpos mtpos; 3292 int block_offset = 0, position = tape->first_frame_position; 3293 void __user *argp = (void __user *)arg; 3294 3295#if IDETAPE_DEBUG_LOG 3296 if (tape->debug_level >= 3) 3297 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_ioctl, " 3298 "cmd=%u\n", cmd); 3299#endif /* IDETAPE_DEBUG_LOG */ 3300 3301 tape->restart_speed_control_req = 1; 3302 if (tape->chrdev_direction == idetape_direction_write) { 3303 idetape_empty_write_pipeline(drive); 3304 idetape_flush_tape_buffers(drive); 3305 } 3306 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 3307 block_offset = idetape_pipeline_size(drive) / (tape->tape_block_size * tape->user_bs_factor); 3308 if ((position = idetape_read_position(drive)) < 0) 3309 return -EIO; 3310 } 3311 switch (cmd) { 3312 case MTIOCTOP: 3313 if (copy_from_user(&mtop, argp, sizeof (struct mtop))) 3314 return -EFAULT; 3315 return (idetape_mtioctop(drive,mtop.mt_op,mtop.mt_count)); 3316 case MTIOCGET: 3317 memset(&mtget, 0, sizeof (struct mtget)); 3318 mtget.mt_type = MT_ISSCSI2; 3319 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 3320 mtget.mt_dsreg = ((tape->tape_block_size * tape->user_bs_factor) << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 3321 if (tape->drv_write_prot) { 3322 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 3323 } 3324 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 3325 return -EFAULT; 3326 return 0; 3327 case MTIOCPOS: 3328 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 3329 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 3330 return -EFAULT; 3331 return 0; 3332 default: 3333 if (tape->chrdev_direction == idetape_direction_read) 3334 idetape_discard_read_pipeline(drive, 1); 3335 return idetape_blkdev_ioctl(drive, cmd, arg); 3336 } 3337} 3338 3339/* 3340 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 3341 * block size with the reported value. 3342 */ 3343static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 3344{ 3345 idetape_tape_t *tape = drive->driver_data; 3346 idetape_pc_t pc; 3347 3348 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 3349 if (idetape_queue_pc_tail(drive, &pc)) { 3350 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 3351 if (tape->tape_block_size == 0) { 3352 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 3353 "block size, assuming 32k\n"); 3354 tape->tape_block_size = 32768; 3355 } 3356 return; 3357 } 3358 tape->tape_block_size = (pc.buffer[4 + 5] << 16) + 3359 (pc.buffer[4 + 6] << 8) + 3360 pc.buffer[4 + 7]; 3361 tape->drv_write_prot = (pc.buffer[2] & 0x80) >> 7; 3362} 3363 3364/* 3365 * Our character device open function. 3366 */ 3367static int idetape_chrdev_open (struct inode *inode, struct file *filp) 3368{ 3369 unsigned int minor = iminor(inode), i = minor & ~0xc0; 3370 ide_drive_t *drive; 3371 idetape_tape_t *tape; 3372 idetape_pc_t pc; 3373 int retval; 3374 3375 /* 3376 * We really want to do nonseekable_open(inode, filp); here, but some 3377 * versions of tar incorrectly call lseek on tapes and bail out if that 3378 * fails. So we disallow pread() and pwrite(), but permit lseeks. 3379 */ 3380 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 3381 3382#if IDETAPE_DEBUG_LOG 3383 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_open\n"); 3384#endif /* IDETAPE_DEBUG_LOG */ 3385 3386 if (i >= MAX_HWIFS * MAX_DRIVES) 3387 return -ENXIO; 3388 3389 if (!(tape = ide_tape_chrdev_get(i))) 3390 return -ENXIO; 3391 3392 drive = tape->drive; 3393 3394 filp->private_data = tape; 3395 3396 if (test_and_set_bit(IDETAPE_BUSY, &tape->flags)) { 3397 retval = -EBUSY; 3398 goto out_put_tape; 3399 } 3400 3401 retval = idetape_wait_ready(drive, 60 * HZ); 3402 if (retval) { 3403 clear_bit(IDETAPE_BUSY, &tape->flags); 3404 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 3405 goto out_put_tape; 3406 } 3407 3408 idetape_read_position(drive); 3409 if (!test_bit(IDETAPE_ADDRESS_VALID, &tape->flags)) 3410 (void)idetape_rewind_tape(drive); 3411 3412 if (tape->chrdev_direction != idetape_direction_read) 3413 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 3414 3415 /* Read block size and write protect status from drive. */ 3416 ide_tape_get_bsize_from_bdesc(drive); 3417 3418 /* Set write protect flag if device is opened as read-only. */ 3419 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 3420 tape->write_prot = 1; 3421 else 3422 tape->write_prot = tape->drv_write_prot; 3423 3424 /* Make sure drive isn't write protected if user wants to write. */ 3425 if (tape->write_prot) { 3426 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 3427 (filp->f_flags & O_ACCMODE) == O_RDWR) { 3428 clear_bit(IDETAPE_BUSY, &tape->flags); 3429 retval = -EROFS; 3430 goto out_put_tape; 3431 } 3432 } 3433 3434 /* 3435 * Lock the tape drive door so user can't eject. 3436 */ 3437 if (tape->chrdev_direction == idetape_direction_none) { 3438 if (idetape_create_prevent_cmd(drive, &pc, 1)) { 3439 if (!idetape_queue_pc_tail(drive, &pc)) { 3440 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 3441 tape->door_locked = DOOR_LOCKED; 3442 } 3443 } 3444 } 3445 idetape_restart_speed_control(drive); 3446 tape->restart_speed_control_req = 0; 3447 return 0; 3448 3449out_put_tape: 3450 ide_tape_put(tape); 3451 return retval; 3452} 3453 3454static void idetape_write_release (ide_drive_t *drive, unsigned int minor) 3455{ 3456 idetape_tape_t *tape = drive->driver_data; 3457 3458 idetape_empty_write_pipeline(drive); 3459 tape->merge_stage = __idetape_kmalloc_stage(tape, 1, 0); 3460 if (tape->merge_stage != NULL) { 3461 idetape_pad_zeros(drive, tape->tape_block_size * (tape->user_bs_factor - 1)); 3462 __idetape_kfree_stage(tape->merge_stage); 3463 tape->merge_stage = NULL; 3464 } 3465 idetape_write_filemark(drive); 3466 idetape_flush_tape_buffers(drive); 3467 idetape_flush_tape_buffers(drive); 3468} 3469 3470/* 3471 * Our character device release function. 3472 */ 3473static int idetape_chrdev_release (struct inode *inode, struct file *filp) 3474{ 3475 struct ide_tape_obj *tape = ide_tape_f(filp); 3476 ide_drive_t *drive = tape->drive; 3477 idetape_pc_t pc; 3478 unsigned int minor = iminor(inode); 3479 3480 lock_kernel(); 3481 tape = drive->driver_data; 3482#if IDETAPE_DEBUG_LOG 3483 if (tape->debug_level >= 3) 3484 printk(KERN_INFO "ide-tape: Reached idetape_chrdev_release\n"); 3485#endif /* IDETAPE_DEBUG_LOG */ 3486 3487 if (tape->chrdev_direction == idetape_direction_write) 3488 idetape_write_release(drive, minor); 3489 if (tape->chrdev_direction == idetape_direction_read) { 3490 if (minor < 128) 3491 idetape_discard_read_pipeline(drive, 1); 3492 else 3493 idetape_wait_for_pipeline(drive); 3494 } 3495 if (tape->cache_stage != NULL) { 3496 __idetape_kfree_stage(tape->cache_stage); 3497 tape->cache_stage = NULL; 3498 } 3499 if (minor < 128 && test_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags)) 3500 (void) idetape_rewind_tape(drive); 3501 if (tape->chrdev_direction == idetape_direction_none) { 3502 if (tape->door_locked == DOOR_LOCKED) { 3503 if (idetape_create_prevent_cmd(drive, &pc, 0)) { 3504 if (!idetape_queue_pc_tail(drive, &pc)) 3505 tape->door_locked = DOOR_UNLOCKED; 3506 } 3507 } 3508 } 3509 clear_bit(IDETAPE_BUSY, &tape->flags); 3510 ide_tape_put(tape); 3511 unlock_kernel(); 3512 return 0; 3513} 3514 3515/* 3516 * idetape_identify_device is called to check the contents of the 3517 * ATAPI IDENTIFY command results. We return: 3518 * 3519 * 1 If the tape can be supported by us, based on the information 3520 * we have so far. 3521 * 3522 * 0 If this tape driver is not currently supported by us. 3523 */ 3524static int idetape_identify_device (ide_drive_t *drive) 3525{ 3526 struct idetape_id_gcw gcw; 3527 struct hd_driveid *id = drive->id; 3528 3529 if (drive->id_read == 0) 3530 return 1; 3531 3532 *((unsigned short *) &gcw) = id->config; 3533 3534 /* Check that we can support this device */ 3535 3536 if (gcw.protocol != 2) 3537 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n", 3538 gcw.protocol); 3539 else if (gcw.device_type != 1) 3540 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set " 3541 "to tape\n", gcw.device_type); 3542 else if (!gcw.removable) 3543 printk(KERN_ERR "ide-tape: The removable flag is not set\n"); 3544 else if (gcw.packet_size != 0) { 3545 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12 " 3546 "bytes long\n", gcw.packet_size); 3547 } else 3548 return 1; 3549 return 0; 3550} 3551 3552static void idetape_get_inquiry_results(ide_drive_t *drive) 3553{ 3554 char *r; 3555 idetape_tape_t *tape = drive->driver_data; 3556 idetape_pc_t pc; 3557 3558 idetape_create_inquiry_cmd(&pc); 3559 if (idetape_queue_pc_tail(drive, &pc)) { 3560 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 3561 tape->name); 3562 return; 3563 } 3564 memcpy(tape->vendor_id, &pc.buffer[8], 8); 3565 memcpy(tape->product_id, &pc.buffer[16], 16); 3566 memcpy(tape->firmware_revision, &pc.buffer[32], 4); 3567 3568 ide_fixstring(tape->vendor_id, 10, 0); 3569 ide_fixstring(tape->product_id, 18, 0); 3570 ide_fixstring(tape->firmware_revision, 6, 0); 3571 r = tape->firmware_revision; 3572 if (*(r + 1) == '.') 3573 tape->firmware_revision_num = (*r - '0') * 100 + 3574 (*(r + 2) - '0') * 10 + *(r + 3) - '0'; 3575 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n", 3576 drive->name, tape->name, tape->vendor_id, 3577 tape->product_id, tape->firmware_revision); 3578} 3579 3580/* 3581 * Ask the tape about its various parameters. In particular, we will adjust our 3582 * data transfer buffer size to the recommended value as returned by the tape. 3583 */ 3584static void idetape_get_mode_sense_results (ide_drive_t *drive) 3585{ 3586 idetape_tape_t *tape = drive->driver_data; 3587 idetape_pc_t pc; 3588 u8 *caps; 3589 u8 speed, max_speed; 3590 3591 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 3592 if (idetape_queue_pc_tail(drive, &pc)) { 3593 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 3594 " some default values\n"); 3595 tape->tape_block_size = 512; 3596 put_unaligned(52, (u16 *)&tape->caps[12]); 3597 put_unaligned(540, (u16 *)&tape->caps[14]); 3598 put_unaligned(6*52, (u16 *)&tape->caps[16]); 3599 return; 3600 } 3601 caps = pc.buffer + 4 + pc.buffer[3]; 3602 3603 /* convert to host order and save for later use */ 3604 speed = be16_to_cpu(*(u16 *)&caps[14]); 3605 max_speed = be16_to_cpu(*(u16 *)&caps[8]); 3606 3607 put_unaligned(max_speed, (u16 *)&caps[8]); 3608 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]); 3609 put_unaligned(speed, (u16 *)&caps[14]); 3610 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]); 3611 3612 if (!speed) { 3613 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 3614 "(assuming 650KB/sec)\n", drive->name); 3615 put_unaligned(650, (u16 *)&caps[14]); 3616 } 3617 if (!max_speed) { 3618 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 3619 "(assuming 650KB/sec)\n", drive->name); 3620 put_unaligned(650, (u16 *)&caps[8]); 3621 } 3622 3623 memcpy(&tape->caps, caps, 20); 3624 if (caps[7] & 0x02) 3625 tape->tape_block_size = 512; 3626 else if (caps[7] & 0x04) 3627 tape->tape_block_size = 1024; 3628} 3629 3630#ifdef CONFIG_IDE_PROC_FS 3631static void idetape_add_settings (ide_drive_t *drive) 3632{ 3633 idetape_tape_t *tape = drive->driver_data; 3634 3635/* 3636 * drive setting name read/write data type min max mul_factor div_factor data pointer set function 3637 */ 3638 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff, 3639 1, 2, (u16 *)&tape->caps[16], NULL); 3640 ide_add_setting(drive, "pipeline_min", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->min_pipeline, NULL); 3641 ide_add_setting(drive, "pipeline", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_stages, NULL); 3642 ide_add_setting(drive, "pipeline_max", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_pipeline, NULL); 3643 ide_add_setting(drive, "pipeline_used", SETTING_READ, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_stages, NULL); 3644 ide_add_setting(drive, "pipeline_pending", SETTING_READ, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_pending_stages, NULL); 3645 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff, 3646 1, 1, (u16 *)&tape->caps[14], NULL); 3647 ide_add_setting(drive, "stage", SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1024, &tape->stage_size, NULL); 3648 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN, IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_frequency, NULL); 3649 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1, 1, &drive->dsc_overlap, NULL); 3650 ide_add_setting(drive, "pipeline_head_speed_c",SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->controlled_pipeline_head_speed, NULL); 3651 ide_add_setting(drive, "pipeline_head_speed_u",SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->uncontrolled_pipeline_head_speed,NULL); 3652 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->avg_speed, NULL); 3653 ide_add_setting(drive, "debug_level", SETTING_RW, TYPE_INT, 0, 0xffff, 1, 1, &tape->debug_level, NULL); 3654} 3655#else 3656static inline void idetape_add_settings(ide_drive_t *drive) { ; } 3657#endif 3658 3659/* 3660 * ide_setup is called to: 3661 * 3662 * 1. Initialize our various state variables. 3663 * 2. Ask the tape for its capabilities. 3664 * 3. Allocate a buffer which will be used for data 3665 * transfer. The buffer size is chosen based on 3666 * the recommendation which we received in step (2). 3667 * 3668 * Note that at this point ide.c already assigned us an irq, so that 3669 * we can queue requests here and wait for their completion. 3670 */ 3671static void idetape_setup (ide_drive_t *drive, idetape_tape_t *tape, int minor) 3672{ 3673 unsigned long t1, tmid, tn, t; 3674 int speed; 3675 struct idetape_id_gcw gcw; 3676 int stage_size; 3677 struct sysinfo si; 3678 u16 *ctl = (u16 *)&tape->caps[12]; 3679 3680 spin_lock_init(&tape->spinlock); 3681 drive->dsc_overlap = 1; 3682 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 3683 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 3684 tape->name); 3685 drive->dsc_overlap = 0; 3686 } 3687 /* Seagate Travan drives do not support DSC overlap. */ 3688 if (strstr(drive->id->model, "Seagate STT3401")) 3689 drive->dsc_overlap = 0; 3690 tape->minor = minor; 3691 tape->name[0] = 'h'; 3692 tape->name[1] = 't'; 3693 tape->name[2] = '0' + minor; 3694 tape->chrdev_direction = idetape_direction_none; 3695 tape->pc = tape->pc_stack; 3696 tape->max_insert_speed = 10000; 3697 tape->speed_control = 1; 3698 *((unsigned short *) &gcw) = drive->id->config; 3699 if (gcw.drq_type == 1) 3700 set_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags); 3701 3702 tape->min_pipeline = tape->max_pipeline = tape->max_stages = 10; 3703 3704 idetape_get_inquiry_results(drive); 3705 idetape_get_mode_sense_results(drive); 3706 ide_tape_get_bsize_from_bdesc(drive); 3707 tape->user_bs_factor = 1; 3708 tape->stage_size = *ctl * tape->tape_block_size; 3709 while (tape->stage_size > 0xffff) { 3710 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 3711 *ctl /= 2; 3712 tape->stage_size = *ctl * tape->tape_block_size; 3713 } 3714 stage_size = tape->stage_size; 3715 tape->pages_per_stage = stage_size / PAGE_SIZE; 3716 if (stage_size % PAGE_SIZE) { 3717 tape->pages_per_stage++; 3718 tape->excess_bh_size = PAGE_SIZE - stage_size % PAGE_SIZE; 3719 } 3720 3721 /* Select the "best" DSC read/write polling freq and pipeline size. */ 3722 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 3723 3724 tape->max_stages = speed * 1000 * 10 / tape->stage_size; 3725 3726 /* 3727 * Limit memory use for pipeline to 10% of physical memory 3728 */ 3729 si_meminfo(&si); 3730 if (tape->max_stages * tape->stage_size > si.totalram * si.mem_unit / 10) 3731 tape->max_stages = si.totalram * si.mem_unit / (10 * tape->stage_size); 3732 tape->max_stages = min(tape->max_stages, IDETAPE_MAX_PIPELINE_STAGES); 3733 tape->min_pipeline = min(tape->max_stages, IDETAPE_MIN_PIPELINE_STAGES); 3734 tape->max_pipeline = min(tape->max_stages * 2, IDETAPE_MAX_PIPELINE_STAGES); 3735 if (tape->max_stages == 0) 3736 tape->max_stages = tape->min_pipeline = tape->max_pipeline = 1; 3737 3738 t1 = (tape->stage_size * HZ) / (speed * 1000); 3739 tmid = (*(u16 *)&tape->caps[16] * 32 * HZ) / (speed * 125); 3740 tn = (IDETAPE_FIFO_THRESHOLD * tape->stage_size * HZ) / (speed * 1000); 3741 3742 if (tape->max_stages) 3743 t = tn; 3744 else 3745 t = t1; 3746 3747 /* 3748 * Ensure that the number we got makes sense; limit 3749 * it within IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 3750 */ 3751 tape->best_dsc_rw_frequency = max_t(unsigned long, min_t(unsigned long, t, IDETAPE_DSC_RW_MAX), IDETAPE_DSC_RW_MIN); 3752 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 3753 "%dkB pipeline, %lums tDSC%s\n", 3754 drive->name, tape->name, *(u16 *)&tape->caps[14], 3755 (*(u16 *)&tape->caps[16] * 512) / tape->stage_size, 3756 tape->stage_size / 1024, 3757 tape->max_stages * tape->stage_size / 1024, 3758 tape->best_dsc_rw_frequency * 1000 / HZ, 3759 drive->using_dma ? ", DMA":""); 3760 3761 idetape_add_settings(drive); 3762} 3763 3764static void ide_tape_remove(ide_drive_t *drive) 3765{ 3766 idetape_tape_t *tape = drive->driver_data; 3767 3768 ide_proc_unregister_driver(drive, tape->driver); 3769 3770 ide_unregister_region(tape->disk); 3771 3772 ide_tape_put(tape); 3773} 3774 3775static void ide_tape_release(struct kref *kref) 3776{ 3777 struct ide_tape_obj *tape = to_ide_tape(kref); 3778 ide_drive_t *drive = tape->drive; 3779 struct gendisk *g = tape->disk; 3780 3781 BUG_ON(tape->first_stage != NULL || tape->merge_stage_size); 3782 3783 drive->dsc_overlap = 0; 3784 drive->driver_data = NULL; 3785 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 3786 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 3787 idetape_devs[tape->minor] = NULL; 3788 g->private_data = NULL; 3789 put_disk(g); 3790 kfree(tape); 3791} 3792 3793#ifdef CONFIG_IDE_PROC_FS 3794static int proc_idetape_read_name 3795 (char *page, char **start, off_t off, int count, int *eof, void *data) 3796{ 3797 ide_drive_t *drive = (ide_drive_t *) data; 3798 idetape_tape_t *tape = drive->driver_data; 3799 char *out = page; 3800 int len; 3801 3802 len = sprintf(out, "%s\n", tape->name); 3803 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 3804} 3805 3806static ide_proc_entry_t idetape_proc[] = { 3807 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 3808 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 3809 { NULL, 0, NULL, NULL } 3810}; 3811#endif 3812 3813static int ide_tape_probe(ide_drive_t *); 3814 3815static ide_driver_t idetape_driver = { 3816 .gen_driver = { 3817 .owner = THIS_MODULE, 3818 .name = "ide-tape", 3819 .bus = &ide_bus_type, 3820 }, 3821 .probe = ide_tape_probe, 3822 .remove = ide_tape_remove, 3823 .version = IDETAPE_VERSION, 3824 .media = ide_tape, 3825 .supports_dsc_overlap = 1, 3826 .do_request = idetape_do_request, 3827 .end_request = idetape_end_request, 3828 .error = __ide_error, 3829 .abort = __ide_abort, 3830#ifdef CONFIG_IDE_PROC_FS 3831 .proc = idetape_proc, 3832#endif 3833}; 3834 3835/* 3836 * Our character device supporting functions, passed to register_chrdev. 3837 */ 3838static const struct file_operations idetape_fops = { 3839 .owner = THIS_MODULE, 3840 .read = idetape_chrdev_read, 3841 .write = idetape_chrdev_write, 3842 .ioctl = idetape_chrdev_ioctl, 3843 .open = idetape_chrdev_open, 3844 .release = idetape_chrdev_release, 3845}; 3846 3847static int idetape_open(struct inode *inode, struct file *filp) 3848{ 3849 struct gendisk *disk = inode->i_bdev->bd_disk; 3850 struct ide_tape_obj *tape; 3851 3852 if (!(tape = ide_tape_get(disk))) 3853 return -ENXIO; 3854 3855 return 0; 3856} 3857 3858static int idetape_release(struct inode *inode, struct file *filp) 3859{ 3860 struct gendisk *disk = inode->i_bdev->bd_disk; 3861 struct ide_tape_obj *tape = ide_tape_g(disk); 3862 3863 ide_tape_put(tape); 3864 3865 return 0; 3866} 3867 3868static int idetape_ioctl(struct inode *inode, struct file *file, 3869 unsigned int cmd, unsigned long arg) 3870{ 3871 struct block_device *bdev = inode->i_bdev; 3872 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 3873 ide_drive_t *drive = tape->drive; 3874 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 3875 if (err == -EINVAL) 3876 err = idetape_blkdev_ioctl(drive, cmd, arg); 3877 return err; 3878} 3879 3880static struct block_device_operations idetape_block_ops = { 3881 .owner = THIS_MODULE, 3882 .open = idetape_open, 3883 .release = idetape_release, 3884 .ioctl = idetape_ioctl, 3885}; 3886 3887static int ide_tape_probe(ide_drive_t *drive) 3888{ 3889 idetape_tape_t *tape; 3890 struct gendisk *g; 3891 int minor; 3892 3893 if (!strstr("ide-tape", drive->driver_req)) 3894 goto failed; 3895 if (!drive->present) 3896 goto failed; 3897 if (drive->media != ide_tape) 3898 goto failed; 3899 if (!idetape_identify_device (drive)) { 3900 printk(KERN_ERR "ide-tape: %s: not supported by this version of ide-tape\n", drive->name); 3901 goto failed; 3902 } 3903 if (drive->scsi) { 3904 printk("ide-tape: passing drive %s to ide-scsi emulation.\n", drive->name); 3905 goto failed; 3906 } 3907 if (strstr(drive->id->model, "OnStream DI-")) { 3908 printk(KERN_WARNING "ide-tape: Use drive %s with ide-scsi emulation and osst.\n", drive->name); 3909 printk(KERN_WARNING "ide-tape: OnStream support will be removed soon from ide-tape!\n"); 3910 } 3911 tape = kzalloc(sizeof (idetape_tape_t), GFP_KERNEL); 3912 if (tape == NULL) { 3913 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape structure\n", drive->name); 3914 goto failed; 3915 } 3916 3917 g = alloc_disk(1 << PARTN_BITS); 3918 if (!g) 3919 goto out_free_tape; 3920 3921 ide_init_disk(g, drive); 3922 3923 ide_proc_register_driver(drive, &idetape_driver); 3924 3925 kref_init(&tape->kref); 3926 3927 tape->drive = drive; 3928 tape->driver = &idetape_driver; 3929 tape->disk = g; 3930 3931 g->private_data = &tape->driver; 3932 3933 drive->driver_data = tape; 3934 3935 mutex_lock(&idetape_ref_mutex); 3936 for (minor = 0; idetape_devs[minor]; minor++) 3937 ; 3938 idetape_devs[minor] = tape; 3939 mutex_unlock(&idetape_ref_mutex); 3940 3941 idetape_setup(drive, tape, minor); 3942 3943 device_create(idetape_sysfs_class, &drive->gendev, 3944 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name); 3945 device_create(idetape_sysfs_class, &drive->gendev, 3946 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name); 3947 3948 g->fops = &idetape_block_ops; 3949 ide_register_region(g); 3950 3951 return 0; 3952 3953out_free_tape: 3954 kfree(tape); 3955failed: 3956 return -ENODEV; 3957} 3958 3959MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 3960MODULE_LICENSE("GPL"); 3961 3962static void __exit idetape_exit (void) 3963{ 3964 driver_unregister(&idetape_driver.gen_driver); 3965 class_destroy(idetape_sysfs_class); 3966 unregister_chrdev(IDETAPE_MAJOR, "ht"); 3967} 3968 3969static int __init idetape_init(void) 3970{ 3971 int error = 1; 3972 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 3973 if (IS_ERR(idetape_sysfs_class)) { 3974 idetape_sysfs_class = NULL; 3975 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 3976 error = -EBUSY; 3977 goto out; 3978 } 3979 3980 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 3981 printk(KERN_ERR "ide-tape: Failed to register character device interface\n"); 3982 error = -EBUSY; 3983 goto out_free_class; 3984 } 3985 3986 error = driver_register(&idetape_driver.gen_driver); 3987 if (error) 3988 goto out_free_driver; 3989 3990 return 0; 3991 3992out_free_driver: 3993 driver_unregister(&idetape_driver.gen_driver); 3994out_free_class: 3995 class_destroy(idetape_sysfs_class); 3996out: 3997 return error; 3998} 3999 4000MODULE_ALIAS("ide:*m-tape*"); 4001module_init(idetape_init); 4002module_exit(idetape_exit); 4003MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 4004