ide-tape.c revision 8004a8c9744842a5a32b71d3a8093c652972bb23
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 48enum { 49 /* output errors only */ 50 DBG_ERR = (1 << 0), 51 /* output all sense key/asc */ 52 DBG_SENSE = (1 << 1), 53 /* info regarding all chrdev-related procedures */ 54 DBG_CHRDEV = (1 << 2), 55 /* all remaining procedures */ 56 DBG_PROCS = (1 << 3), 57 /* buffer alloc info (pc_stack & rq_stack) */ 58 DBG_PCRQ_STACK = (1 << 4), 59}; 60 61/* define to see debug info */ 62#define IDETAPE_DEBUG_LOG 0 63 64#if IDETAPE_DEBUG_LOG 65#define debug_log(lvl, fmt, args...) \ 66{ \ 67 if (tape->debug_mask & lvl) \ 68 printk(KERN_INFO "ide-tape: " fmt, ## args); \ 69} 70#else 71#define debug_log(lvl, fmt, args...) do {} while (0) 72#endif 73 74/**************************** Tunable parameters *****************************/ 75 76 77/* 78 * Pipelined mode parameters. 79 * 80 * We try to use the minimum number of stages which is enough to 81 * keep the tape constantly streaming. To accomplish that, we implement 82 * a feedback loop around the maximum number of stages: 83 * 84 * We start from MIN maximum stages (we will not even use MIN stages 85 * if we don't need them), increment it by RATE*(MAX-MIN) 86 * whenever we sense that the pipeline is empty, until we reach 87 * the optimum value or until we reach MAX. 88 * 89 * Setting the following parameter to 0 is illegal: the pipelined mode 90 * cannot be disabled (calculate_speeds() divides by tape->max_stages.) 91 */ 92#define IDETAPE_MIN_PIPELINE_STAGES 1 93#define IDETAPE_MAX_PIPELINE_STAGES 400 94#define IDETAPE_INCREASE_STAGES_RATE 20 95 96/* 97 * After each failed packet command we issue a request sense command 98 * and retry the packet command IDETAPE_MAX_PC_RETRIES times. 99 * 100 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries. 101 */ 102#define IDETAPE_MAX_PC_RETRIES 3 103 104/* 105 * With each packet command, we allocate a buffer of 106 * IDETAPE_PC_BUFFER_SIZE bytes. This is used for several packet 107 * commands (Not for READ/WRITE commands). 108 */ 109#define IDETAPE_PC_BUFFER_SIZE 256 110 111/* 112 * In various places in the driver, we need to allocate storage 113 * for packet commands and requests, which will remain valid while 114 * we leave the driver to wait for an interrupt or a timeout event. 115 */ 116#define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES) 117 118/* 119 * Some drives (for example, Seagate STT3401A Travan) require a very long 120 * timeout, because they don't return an interrupt or clear their busy bit 121 * until after the command completes (even retension commands). 122 */ 123#define IDETAPE_WAIT_CMD (900*HZ) 124 125/* 126 * The following parameter is used to select the point in the internal 127 * tape fifo in which we will start to refill the buffer. Decreasing 128 * the following parameter will improve the system's latency and 129 * interactive response, while using a high value might improve system 130 * throughput. 131 */ 132#define IDETAPE_FIFO_THRESHOLD 2 133 134/* 135 * DSC polling parameters. 136 * 137 * Polling for DSC (a single bit in the status register) is a very 138 * important function in ide-tape. There are two cases in which we 139 * poll for DSC: 140 * 141 * 1. Before a read/write packet command, to ensure that we 142 * can transfer data from/to the tape's data buffers, without 143 * causing an actual media access. In case the tape is not 144 * ready yet, we take out our request from the device 145 * request queue, so that ide.c will service requests from 146 * the other device on the same interface meanwhile. 147 * 148 * 2. After the successful initialization of a "media access 149 * packet command", which is a command which can take a long 150 * time to complete (it can be several seconds or even an hour). 151 * 152 * Again, we postpone our request in the middle to free the bus 153 * for the other device. The polling frequency here should be 154 * lower than the read/write frequency since those media access 155 * commands are slow. We start from a "fast" frequency - 156 * IDETAPE_DSC_MA_FAST (one second), and if we don't receive DSC 157 * after IDETAPE_DSC_MA_THRESHOLD (5 minutes), we switch it to a 158 * lower frequency - IDETAPE_DSC_MA_SLOW (1 minute). 159 * 160 * We also set a timeout for the timer, in case something goes wrong. 161 * The timeout should be longer then the maximum execution time of a 162 * tape operation. 163 */ 164 165/* 166 * DSC timings. 167 */ 168#define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */ 169#define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */ 170#define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */ 171#define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */ 172#define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */ 173#define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */ 174#define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */ 175 176/*************************** End of tunable parameters ***********************/ 177 178/* 179 * Read/Write error simulation 180 */ 181#define SIMULATE_ERRORS 0 182 183/* 184 * For general magnetic tape device compatibility. 185 */ 186typedef enum { 187 idetape_direction_none, 188 idetape_direction_read, 189 idetape_direction_write 190} idetape_chrdev_direction_t; 191 192struct idetape_bh { 193 u32 b_size; 194 atomic_t b_count; 195 struct idetape_bh *b_reqnext; 196 char *b_data; 197}; 198 199/* 200 * Our view of a packet command. 201 */ 202typedef struct idetape_packet_command_s { 203 u8 c[12]; /* Actual packet bytes */ 204 int retries; /* On each retry, we increment retries */ 205 int error; /* Error code */ 206 int request_transfer; /* Bytes to transfer */ 207 int actually_transferred; /* Bytes actually transferred */ 208 int buffer_size; /* Size of our data buffer */ 209 struct idetape_bh *bh; 210 char *b_data; 211 int b_count; 212 u8 *buffer; /* Data buffer */ 213 u8 *current_position; /* Pointer into the above buffer */ 214 ide_startstop_t (*callback) (ide_drive_t *); /* Called when this packet command is completed */ 215 u8 pc_buffer[IDETAPE_PC_BUFFER_SIZE]; /* Temporary buffer */ 216 unsigned long flags; /* Status/Action bit flags: long for set_bit */ 217} idetape_pc_t; 218 219/* 220 * Packet command flag bits. 221 */ 222/* Set when an error is considered normal - We won't retry */ 223#define PC_ABORT 0 224/* 1 When polling for DSC on a media access command */ 225#define PC_WAIT_FOR_DSC 1 226/* 1 when we prefer to use DMA if possible */ 227#define PC_DMA_RECOMMENDED 2 228/* 1 while DMA in progress */ 229#define PC_DMA_IN_PROGRESS 3 230/* 1 when encountered problem during DMA */ 231#define PC_DMA_ERROR 4 232/* Data direction */ 233#define PC_WRITING 5 234 235/* 236 * A pipeline stage. 237 */ 238typedef struct idetape_stage_s { 239 struct request rq; /* The corresponding request */ 240 struct idetape_bh *bh; /* The data buffers */ 241 struct idetape_stage_s *next; /* Pointer to the next stage */ 242} idetape_stage_t; 243 244/* 245 * Most of our global data which we need to save even as we leave the 246 * driver due to an interrupt or a timer event is stored in a variable 247 * of type idetape_tape_t, defined below. 248 */ 249typedef struct ide_tape_obj { 250 ide_drive_t *drive; 251 ide_driver_t *driver; 252 struct gendisk *disk; 253 struct kref kref; 254 255 /* 256 * Since a typical character device operation requires more 257 * than one packet command, we provide here enough memory 258 * for the maximum of interconnected packet commands. 259 * The packet commands are stored in the circular array pc_stack. 260 * pc_stack_index points to the last used entry, and warps around 261 * to the start when we get to the last array entry. 262 * 263 * pc points to the current processed packet command. 264 * 265 * failed_pc points to the last failed packet command, or contains 266 * NULL if we do not need to retry any packet command. This is 267 * required since an additional packet command is needed before the 268 * retry, to get detailed information on what went wrong. 269 */ 270 /* Current packet command */ 271 idetape_pc_t *pc; 272 /* Last failed packet command */ 273 idetape_pc_t *failed_pc; 274 /* Packet command stack */ 275 idetape_pc_t pc_stack[IDETAPE_PC_STACK]; 276 /* Next free packet command storage space */ 277 int pc_stack_index; 278 struct request rq_stack[IDETAPE_PC_STACK]; 279 /* We implement a circular array */ 280 int rq_stack_index; 281 282 /* 283 * DSC polling variables. 284 * 285 * While polling for DSC we use postponed_rq to postpone the 286 * current request so that ide.c will be able to service 287 * pending requests on the other device. Note that at most 288 * we will have only one DSC (usually data transfer) request 289 * in the device request queue. Additional requests can be 290 * queued in our internal pipeline, but they will be visible 291 * to ide.c only one at a time. 292 */ 293 struct request *postponed_rq; 294 /* The time in which we started polling for DSC */ 295 unsigned long dsc_polling_start; 296 /* Timer used to poll for dsc */ 297 struct timer_list dsc_timer; 298 /* Read/Write dsc polling frequency */ 299 unsigned long best_dsc_rw_frequency; 300 /* The current polling frequency */ 301 unsigned long dsc_polling_frequency; 302 /* Maximum waiting time */ 303 unsigned long dsc_timeout; 304 305 /* 306 * Read position information 307 */ 308 u8 partition; 309 /* Current block */ 310 unsigned int first_frame_position; 311 unsigned int last_frame_position; 312 unsigned int blocks_in_buffer; 313 314 /* 315 * Last error information 316 */ 317 u8 sense_key, asc, ascq; 318 319 /* 320 * Character device operation 321 */ 322 unsigned int minor; 323 /* device name */ 324 char name[4]; 325 /* Current character device data transfer direction */ 326 idetape_chrdev_direction_t chrdev_direction; 327 328 /* 329 * Device information 330 */ 331 /* Usually 512 or 1024 bytes */ 332 unsigned short tape_block_size; 333 int user_bs_factor; 334 335 /* Copy of the tape's Capabilities and Mechanical Page */ 336 u8 caps[20]; 337 338 /* 339 * Active data transfer request parameters. 340 * 341 * At most, there is only one ide-tape originated data transfer 342 * request in the device request queue. This allows ide.c to 343 * easily service requests from the other device when we 344 * postpone our active request. In the pipelined operation 345 * mode, we use our internal pipeline structure to hold 346 * more data requests. 347 * 348 * The data buffer size is chosen based on the tape's 349 * recommendation. 350 */ 351 /* Pointer to the request which is waiting in the device request queue */ 352 struct request *active_data_request; 353 /* Data buffer size (chosen based on the tape's recommendation */ 354 int stage_size; 355 idetape_stage_t *merge_stage; 356 int merge_stage_size; 357 struct idetape_bh *bh; 358 char *b_data; 359 int b_count; 360 361 /* 362 * Pipeline parameters. 363 * 364 * To accomplish non-pipelined mode, we simply set the following 365 * variables to zero (or NULL, where appropriate). 366 */ 367 /* Number of currently used stages */ 368 int nr_stages; 369 /* Number of pending stages */ 370 int nr_pending_stages; 371 /* We will not allocate more than this number of stages */ 372 int max_stages, min_pipeline, max_pipeline; 373 /* The first stage which will be removed from the pipeline */ 374 idetape_stage_t *first_stage; 375 /* The currently active stage */ 376 idetape_stage_t *active_stage; 377 /* Will be serviced after the currently active request */ 378 idetape_stage_t *next_stage; 379 /* New requests will be added to the pipeline here */ 380 idetape_stage_t *last_stage; 381 /* Optional free stage which we can use */ 382 idetape_stage_t *cache_stage; 383 int pages_per_stage; 384 /* Wasted space in each stage */ 385 int excess_bh_size; 386 387 /* Status/Action flags: long for set_bit */ 388 unsigned long flags; 389 /* protects the ide-tape queue */ 390 spinlock_t spinlock; 391 392 /* 393 * Measures average tape speed 394 */ 395 unsigned long avg_time; 396 int avg_size; 397 int avg_speed; 398 399 char vendor_id[10]; 400 char product_id[18]; 401 char firmware_revision[6]; 402 int firmware_revision_num; 403 404 /* the door is currently locked */ 405 int door_locked; 406 /* the tape hardware is write protected */ 407 char drv_write_prot; 408 /* the tape is write protected (hardware or opened as read-only) */ 409 char write_prot; 410 411 /* 412 * Limit the number of times a request can 413 * be postponed, to avoid an infinite postpone 414 * deadlock. 415 */ 416 /* request postpone count limit */ 417 int postpone_cnt; 418 419 /* 420 * Measures number of frames: 421 * 422 * 1. written/read to/from the driver pipeline (pipeline_head). 423 * 2. written/read to/from the tape buffers (idetape_bh). 424 * 3. written/read by the tape to/from the media (tape_head). 425 */ 426 int pipeline_head; 427 int buffer_head; 428 int tape_head; 429 int last_tape_head; 430 431 /* 432 * Speed control at the tape buffers input/output 433 */ 434 unsigned long insert_time; 435 int insert_size; 436 int insert_speed; 437 int max_insert_speed; 438 int measure_insert_time; 439 440 /* 441 * Measure tape still time, in milliseconds 442 */ 443 unsigned long tape_still_time_begin; 444 int tape_still_time; 445 446 /* 447 * Speed regulation negative feedback loop 448 */ 449 int speed_control; 450 int pipeline_head_speed; 451 int controlled_pipeline_head_speed; 452 int uncontrolled_pipeline_head_speed; 453 int controlled_last_pipeline_head; 454 int uncontrolled_last_pipeline_head; 455 unsigned long uncontrolled_pipeline_head_time; 456 unsigned long controlled_pipeline_head_time; 457 int controlled_previous_pipeline_head; 458 int uncontrolled_previous_pipeline_head; 459 unsigned long controlled_previous_head_time; 460 unsigned long uncontrolled_previous_head_time; 461 int restart_speed_control_req; 462 463 u32 debug_mask; 464} idetape_tape_t; 465 466static DEFINE_MUTEX(idetape_ref_mutex); 467 468static struct class *idetape_sysfs_class; 469 470#define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref) 471 472#define ide_tape_g(disk) \ 473 container_of((disk)->private_data, struct ide_tape_obj, driver) 474 475static struct ide_tape_obj *ide_tape_get(struct gendisk *disk) 476{ 477 struct ide_tape_obj *tape = NULL; 478 479 mutex_lock(&idetape_ref_mutex); 480 tape = ide_tape_g(disk); 481 if (tape) 482 kref_get(&tape->kref); 483 mutex_unlock(&idetape_ref_mutex); 484 return tape; 485} 486 487static void ide_tape_release(struct kref *); 488 489static void ide_tape_put(struct ide_tape_obj *tape) 490{ 491 mutex_lock(&idetape_ref_mutex); 492 kref_put(&tape->kref, ide_tape_release); 493 mutex_unlock(&idetape_ref_mutex); 494} 495 496/* 497 * Tape door status 498 */ 499#define DOOR_UNLOCKED 0 500#define DOOR_LOCKED 1 501#define DOOR_EXPLICITLY_LOCKED 2 502 503/* 504 * Tape flag bits values. 505 */ 506#define IDETAPE_IGNORE_DSC 0 507#define IDETAPE_ADDRESS_VALID 1 /* 0 When the tape position is unknown */ 508#define IDETAPE_BUSY 2 /* Device already opened */ 509#define IDETAPE_PIPELINE_ERROR 3 /* Error detected in a pipeline stage */ 510#define IDETAPE_DETECT_BS 4 /* Attempt to auto-detect the current user block size */ 511#define IDETAPE_FILEMARK 5 /* Currently on a filemark */ 512#define IDETAPE_DRQ_INTERRUPT 6 /* DRQ interrupt device */ 513#define IDETAPE_READ_ERROR 7 514#define IDETAPE_PIPELINE_ACTIVE 8 /* pipeline active */ 515/* 0 = no tape is loaded, so we don't rewind after ejecting */ 516#define IDETAPE_MEDIUM_PRESENT 9 517 518/* 519 * Some defines for the READ BUFFER command 520 */ 521#define IDETAPE_RETRIEVE_FAULTY_BLOCK 6 522 523/* 524 * Some defines for the SPACE command 525 */ 526#define IDETAPE_SPACE_OVER_FILEMARK 1 527#define IDETAPE_SPACE_TO_EOD 3 528 529/* 530 * Some defines for the LOAD UNLOAD command 531 */ 532#define IDETAPE_LU_LOAD_MASK 1 533#define IDETAPE_LU_RETENSION_MASK 2 534#define IDETAPE_LU_EOT_MASK 4 535 536/* 537 * Special requests for our block device strategy routine. 538 * 539 * In order to service a character device command, we add special 540 * requests to the tail of our block device request queue and wait 541 * for their completion. 542 */ 543 544enum { 545 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */ 546 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */ 547 REQ_IDETAPE_READ = (1 << 2), 548 REQ_IDETAPE_WRITE = (1 << 3), 549 REQ_IDETAPE_READ_BUFFER = (1 << 4), 550}; 551 552/* 553 * Error codes which are returned in rq->errors to the higher part 554 * of the driver. 555 */ 556#define IDETAPE_ERROR_GENERAL 101 557#define IDETAPE_ERROR_FILEMARK 102 558#define IDETAPE_ERROR_EOD 103 559 560/* 561 * The following is used to format the general configuration word of 562 * the ATAPI IDENTIFY DEVICE command. 563 */ 564struct idetape_id_gcw { 565 unsigned packet_size :2; /* Packet Size */ 566 unsigned reserved234 :3; /* Reserved */ 567 unsigned drq_type :2; /* Command packet DRQ type */ 568 unsigned removable :1; /* Removable media */ 569 unsigned device_type :5; /* Device type */ 570 unsigned reserved13 :1; /* Reserved */ 571 unsigned protocol :2; /* Protocol type */ 572}; 573 574/* 575 * READ POSITION packet command - Data Format (From Table 6-57) 576 */ 577typedef struct { 578 unsigned reserved0_10 :2; /* Reserved */ 579 unsigned bpu :1; /* Block Position Unknown */ 580 unsigned reserved0_543 :3; /* Reserved */ 581 unsigned eop :1; /* End Of Partition */ 582 unsigned bop :1; /* Beginning Of Partition */ 583 u8 partition; /* Partition Number */ 584 u8 reserved2, reserved3; /* Reserved */ 585 u32 first_block; /* First Block Location */ 586 u32 last_block; /* Last Block Location (Optional) */ 587 u8 reserved12; /* Reserved */ 588 u8 blocks_in_buffer[3]; /* Blocks In Buffer - (Optional) */ 589 u32 bytes_in_buffer; /* Bytes In Buffer (Optional) */ 590} idetape_read_position_result_t; 591 592/* Structures related to the SELECT SENSE / MODE SENSE packet commands. */ 593#define IDETAPE_BLOCK_DESCRIPTOR 0 594#define IDETAPE_CAPABILITIES_PAGE 0x2a 595 596/* 597 * The variables below are used for the character device interface. 598 * Additional state variables are defined in our ide_drive_t structure. 599 */ 600static struct ide_tape_obj * idetape_devs[MAX_HWIFS * MAX_DRIVES]; 601 602#define ide_tape_f(file) ((file)->private_data) 603 604static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i) 605{ 606 struct ide_tape_obj *tape = NULL; 607 608 mutex_lock(&idetape_ref_mutex); 609 tape = idetape_devs[i]; 610 if (tape) 611 kref_get(&tape->kref); 612 mutex_unlock(&idetape_ref_mutex); 613 return tape; 614} 615 616/* 617 * Function declarations 618 * 619 */ 620static int idetape_chrdev_release (struct inode *inode, struct file *filp); 621static void idetape_write_release (ide_drive_t *drive, unsigned int minor); 622 623/* 624 * Too bad. The drive wants to send us data which we are not ready to accept. 625 * Just throw it away. 626 */ 627static void idetape_discard_data (ide_drive_t *drive, unsigned int bcount) 628{ 629 while (bcount--) 630 (void) HWIF(drive)->INB(IDE_DATA_REG); 631} 632 633static void idetape_input_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount) 634{ 635 struct idetape_bh *bh = pc->bh; 636 int count; 637 638 while (bcount) { 639 if (bh == NULL) { 640 printk(KERN_ERR "ide-tape: bh == NULL in " 641 "idetape_input_buffers\n"); 642 idetape_discard_data(drive, bcount); 643 return; 644 } 645 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), bcount); 646 HWIF(drive)->atapi_input_bytes(drive, bh->b_data + atomic_read(&bh->b_count), count); 647 bcount -= count; 648 atomic_add(count, &bh->b_count); 649 if (atomic_read(&bh->b_count) == bh->b_size) { 650 bh = bh->b_reqnext; 651 if (bh) 652 atomic_set(&bh->b_count, 0); 653 } 654 } 655 pc->bh = bh; 656} 657 658static void idetape_output_buffers (ide_drive_t *drive, idetape_pc_t *pc, unsigned int bcount) 659{ 660 struct idetape_bh *bh = pc->bh; 661 int count; 662 663 while (bcount) { 664 if (bh == NULL) { 665 printk(KERN_ERR "ide-tape: bh == NULL in " 666 "idetape_output_buffers\n"); 667 return; 668 } 669 count = min((unsigned int)pc->b_count, (unsigned int)bcount); 670 HWIF(drive)->atapi_output_bytes(drive, pc->b_data, count); 671 bcount -= count; 672 pc->b_data += count; 673 pc->b_count -= count; 674 if (!pc->b_count) { 675 pc->bh = bh = bh->b_reqnext; 676 if (bh) { 677 pc->b_data = bh->b_data; 678 pc->b_count = atomic_read(&bh->b_count); 679 } 680 } 681 } 682} 683 684static void idetape_update_buffers (idetape_pc_t *pc) 685{ 686 struct idetape_bh *bh = pc->bh; 687 int count; 688 unsigned int bcount = pc->actually_transferred; 689 690 if (test_bit(PC_WRITING, &pc->flags)) 691 return; 692 while (bcount) { 693 if (bh == NULL) { 694 printk(KERN_ERR "ide-tape: bh == NULL in " 695 "idetape_update_buffers\n"); 696 return; 697 } 698 count = min((unsigned int)bh->b_size, (unsigned int)bcount); 699 atomic_set(&bh->b_count, count); 700 if (atomic_read(&bh->b_count) == bh->b_size) 701 bh = bh->b_reqnext; 702 bcount -= count; 703 } 704 pc->bh = bh; 705} 706 707/* 708 * idetape_next_pc_storage returns a pointer to a place in which we can 709 * safely store a packet command, even though we intend to leave the 710 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet 711 * commands is allocated at initialization time. 712 */ 713static idetape_pc_t *idetape_next_pc_storage (ide_drive_t *drive) 714{ 715 idetape_tape_t *tape = drive->driver_data; 716 717 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index); 718 719 if (tape->pc_stack_index == IDETAPE_PC_STACK) 720 tape->pc_stack_index=0; 721 return (&tape->pc_stack[tape->pc_stack_index++]); 722} 723 724/* 725 * idetape_next_rq_storage is used along with idetape_next_pc_storage. 726 * Since we queue packet commands in the request queue, we need to 727 * allocate a request, along with the allocation of a packet command. 728 */ 729 730/************************************************************** 731 * * 732 * This should get fixed to use kmalloc(.., GFP_ATOMIC) * 733 * followed later on by kfree(). -ml * 734 * * 735 **************************************************************/ 736 737static struct request *idetape_next_rq_storage (ide_drive_t *drive) 738{ 739 idetape_tape_t *tape = drive->driver_data; 740 741 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index); 742 743 if (tape->rq_stack_index == IDETAPE_PC_STACK) 744 tape->rq_stack_index=0; 745 return (&tape->rq_stack[tape->rq_stack_index++]); 746} 747 748/* 749 * idetape_init_pc initializes a packet command. 750 */ 751static void idetape_init_pc (idetape_pc_t *pc) 752{ 753 memset(pc->c, 0, 12); 754 pc->retries = 0; 755 pc->flags = 0; 756 pc->request_transfer = 0; 757 pc->buffer = pc->pc_buffer; 758 pc->buffer_size = IDETAPE_PC_BUFFER_SIZE; 759 pc->bh = NULL; 760 pc->b_data = NULL; 761} 762 763/* 764 * called on each failed packet command retry to analyze the request sense. We 765 * currently do not utilize this information. 766 */ 767static void idetape_analyze_error(ide_drive_t *drive, u8 *sense) 768{ 769 idetape_tape_t *tape = drive->driver_data; 770 idetape_pc_t *pc = tape->failed_pc; 771 772 tape->sense_key = sense[2] & 0xF; 773 tape->asc = sense[12]; 774 tape->ascq = sense[13]; 775 776 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n", 777 pc->c[0], tape->sense_key, tape->asc, tape->ascq); 778 779 /* Correct pc->actually_transferred by asking the tape. */ 780 if (test_bit(PC_DMA_ERROR, &pc->flags)) { 781 pc->actually_transferred = pc->request_transfer - 782 tape->tape_block_size * 783 be32_to_cpu(get_unaligned((u32 *)&sense[3])); 784 idetape_update_buffers(pc); 785 } 786 787 /* 788 * If error was the result of a zero-length read or write command, 789 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives 790 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes. 791 */ 792 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6) 793 /* length == 0 */ 794 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) { 795 if (tape->sense_key == 5) { 796 /* don't report an error, everything's ok */ 797 pc->error = 0; 798 /* don't retry read/write */ 799 set_bit(PC_ABORT, &pc->flags); 800 } 801 } 802 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) { 803 pc->error = IDETAPE_ERROR_FILEMARK; 804 set_bit(PC_ABORT, &pc->flags); 805 } 806 if (pc->c[0] == WRITE_6) { 807 if ((sense[2] & 0x40) || (tape->sense_key == 0xd 808 && tape->asc == 0x0 && tape->ascq == 0x2)) { 809 pc->error = IDETAPE_ERROR_EOD; 810 set_bit(PC_ABORT, &pc->flags); 811 } 812 } 813 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) { 814 if (tape->sense_key == 8) { 815 pc->error = IDETAPE_ERROR_EOD; 816 set_bit(PC_ABORT, &pc->flags); 817 } 818 if (!test_bit(PC_ABORT, &pc->flags) && 819 pc->actually_transferred) 820 pc->retries = IDETAPE_MAX_PC_RETRIES + 1; 821 } 822} 823 824static void idetape_activate_next_stage(ide_drive_t *drive) 825{ 826 idetape_tape_t *tape = drive->driver_data; 827 idetape_stage_t *stage = tape->next_stage; 828 struct request *rq = &stage->rq; 829 830 debug_log(DBG_PROCS, "Enter %s\n", __func__); 831 832 if (stage == NULL) { 833 printk(KERN_ERR "ide-tape: bug: Trying to activate a non" 834 " existing stage\n"); 835 return; 836 } 837 838 rq->rq_disk = tape->disk; 839 rq->buffer = NULL; 840 rq->special = (void *)stage->bh; 841 tape->active_data_request = rq; 842 tape->active_stage = stage; 843 tape->next_stage = stage->next; 844} 845 846/* 847 * idetape_increase_max_pipeline_stages is a part of the feedback 848 * loop which tries to find the optimum number of stages. In the 849 * feedback loop, we are starting from a minimum maximum number of 850 * stages, and if we sense that the pipeline is empty, we try to 851 * increase it, until we reach the user compile time memory limit. 852 */ 853static void idetape_increase_max_pipeline_stages (ide_drive_t *drive) 854{ 855 idetape_tape_t *tape = drive->driver_data; 856 int increase = (tape->max_pipeline - tape->min_pipeline) / 10; 857 858 debug_log(DBG_PROCS, "Enter %s\n", __func__); 859 860 tape->max_stages += max(increase, 1); 861 tape->max_stages = max(tape->max_stages, tape->min_pipeline); 862 tape->max_stages = min(tape->max_stages, tape->max_pipeline); 863} 864 865/* 866 * idetape_kfree_stage calls kfree to completely free a stage, along with 867 * its related buffers. 868 */ 869static void __idetape_kfree_stage (idetape_stage_t *stage) 870{ 871 struct idetape_bh *prev_bh, *bh = stage->bh; 872 int size; 873 874 while (bh != NULL) { 875 if (bh->b_data != NULL) { 876 size = (int) bh->b_size; 877 while (size > 0) { 878 free_page((unsigned long) bh->b_data); 879 size -= PAGE_SIZE; 880 bh->b_data += PAGE_SIZE; 881 } 882 } 883 prev_bh = bh; 884 bh = bh->b_reqnext; 885 kfree(prev_bh); 886 } 887 kfree(stage); 888} 889 890static void idetape_kfree_stage (idetape_tape_t *tape, idetape_stage_t *stage) 891{ 892 __idetape_kfree_stage(stage); 893} 894 895/* 896 * idetape_remove_stage_head removes tape->first_stage from the pipeline. 897 * The caller should avoid race conditions. 898 */ 899static void idetape_remove_stage_head (ide_drive_t *drive) 900{ 901 idetape_tape_t *tape = drive->driver_data; 902 idetape_stage_t *stage; 903 904 debug_log(DBG_PROCS, "Enter %s\n", __func__); 905 906 if (tape->first_stage == NULL) { 907 printk(KERN_ERR "ide-tape: bug: tape->first_stage is NULL\n"); 908 return; 909 } 910 if (tape->active_stage == tape->first_stage) { 911 printk(KERN_ERR "ide-tape: bug: Trying to free our active " 912 "pipeline stage\n"); 913 return; 914 } 915 stage = tape->first_stage; 916 tape->first_stage = stage->next; 917 idetape_kfree_stage(tape, stage); 918 tape->nr_stages--; 919 if (tape->first_stage == NULL) { 920 tape->last_stage = NULL; 921 if (tape->next_stage != NULL) 922 printk(KERN_ERR "ide-tape: bug: tape->next_stage != NULL\n"); 923 if (tape->nr_stages) 924 printk(KERN_ERR "ide-tape: bug: nr_stages should be 0 now\n"); 925 } 926} 927 928/* 929 * This will free all the pipeline stages starting from new_last_stage->next 930 * to the end of the list, and point tape->last_stage to new_last_stage. 931 */ 932static void idetape_abort_pipeline(ide_drive_t *drive, 933 idetape_stage_t *new_last_stage) 934{ 935 idetape_tape_t *tape = drive->driver_data; 936 idetape_stage_t *stage = new_last_stage->next; 937 idetape_stage_t *nstage; 938 939 debug_log(DBG_PROCS, "%s: Enter %s\n", tape->name, __func__); 940 941 while (stage) { 942 nstage = stage->next; 943 idetape_kfree_stage(tape, stage); 944 --tape->nr_stages; 945 --tape->nr_pending_stages; 946 stage = nstage; 947 } 948 if (new_last_stage) 949 new_last_stage->next = NULL; 950 tape->last_stage = new_last_stage; 951 tape->next_stage = NULL; 952} 953 954/* 955 * idetape_end_request is used to finish servicing a request, and to 956 * insert a pending pipeline request into the main device queue. 957 */ 958static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects) 959{ 960 struct request *rq = HWGROUP(drive)->rq; 961 idetape_tape_t *tape = drive->driver_data; 962 unsigned long flags; 963 int error; 964 int remove_stage = 0; 965 idetape_stage_t *active_stage; 966 967 debug_log(DBG_PROCS, "Enter %s\n", __func__); 968 969 switch (uptodate) { 970 case 0: error = IDETAPE_ERROR_GENERAL; break; 971 case 1: error = 0; break; 972 default: error = uptodate; 973 } 974 rq->errors = error; 975 if (error) 976 tape->failed_pc = NULL; 977 978 if (!blk_special_request(rq)) { 979 ide_end_request(drive, uptodate, nr_sects); 980 return 0; 981 } 982 983 spin_lock_irqsave(&tape->spinlock, flags); 984 985 /* The request was a pipelined data transfer request */ 986 if (tape->active_data_request == rq) { 987 active_stage = tape->active_stage; 988 tape->active_stage = NULL; 989 tape->active_data_request = NULL; 990 tape->nr_pending_stages--; 991 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 992 remove_stage = 1; 993 if (error) { 994 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 995 if (error == IDETAPE_ERROR_EOD) 996 idetape_abort_pipeline(drive, active_stage); 997 } 998 } else if (rq->cmd[0] & REQ_IDETAPE_READ) { 999 if (error == IDETAPE_ERROR_EOD) { 1000 set_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 1001 idetape_abort_pipeline(drive, active_stage); 1002 } 1003 } 1004 if (tape->next_stage != NULL) { 1005 idetape_activate_next_stage(drive); 1006 1007 /* 1008 * Insert the next request into the request queue. 1009 */ 1010 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end); 1011 } else if (!error) { 1012 idetape_increase_max_pipeline_stages(drive); 1013 } 1014 } 1015 ide_end_drive_cmd(drive, 0, 0); 1016// blkdev_dequeue_request(rq); 1017// drive->rq = NULL; 1018// end_that_request_last(rq); 1019 1020 if (remove_stage) 1021 idetape_remove_stage_head(drive); 1022 if (tape->active_data_request == NULL) 1023 clear_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags); 1024 spin_unlock_irqrestore(&tape->spinlock, flags); 1025 return 0; 1026} 1027 1028static ide_startstop_t idetape_request_sense_callback (ide_drive_t *drive) 1029{ 1030 idetape_tape_t *tape = drive->driver_data; 1031 1032 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1033 1034 if (!tape->pc->error) { 1035 idetape_analyze_error(drive, tape->pc->buffer); 1036 idetape_end_request(drive, 1, 0); 1037 } else { 1038 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE itself - Aborting request!\n"); 1039 idetape_end_request(drive, 0, 0); 1040 } 1041 return ide_stopped; 1042} 1043 1044static void idetape_create_request_sense_cmd (idetape_pc_t *pc) 1045{ 1046 idetape_init_pc(pc); 1047 pc->c[0] = REQUEST_SENSE; 1048 pc->c[4] = 20; 1049 pc->request_transfer = 20; 1050 pc->callback = &idetape_request_sense_callback; 1051} 1052 1053static void idetape_init_rq(struct request *rq, u8 cmd) 1054{ 1055 memset(rq, 0, sizeof(*rq)); 1056 rq->cmd_type = REQ_TYPE_SPECIAL; 1057 rq->cmd[0] = cmd; 1058} 1059 1060/* 1061 * idetape_queue_pc_head generates a new packet command request in front 1062 * of the request queue, before the current request, so that it will be 1063 * processed immediately, on the next pass through the driver. 1064 * 1065 * idetape_queue_pc_head is called from the request handling part of 1066 * the driver (the "bottom" part). Safe storage for the request should 1067 * be allocated with idetape_next_pc_storage and idetape_next_rq_storage 1068 * before calling idetape_queue_pc_head. 1069 * 1070 * Memory for those requests is pre-allocated at initialization time, and 1071 * is limited to IDETAPE_PC_STACK requests. We assume that we have enough 1072 * space for the maximum possible number of inter-dependent packet commands. 1073 * 1074 * The higher level of the driver - The ioctl handler and the character 1075 * device handling functions should queue request to the lower level part 1076 * and wait for their completion using idetape_queue_pc_tail or 1077 * idetape_queue_rw_tail. 1078 */ 1079static void idetape_queue_pc_head (ide_drive_t *drive, idetape_pc_t *pc,struct request *rq) 1080{ 1081 struct ide_tape_obj *tape = drive->driver_data; 1082 1083 idetape_init_rq(rq, REQ_IDETAPE_PC1); 1084 rq->buffer = (char *) pc; 1085 rq->rq_disk = tape->disk; 1086 (void) ide_do_drive_cmd(drive, rq, ide_preempt); 1087} 1088 1089/* 1090 * idetape_retry_pc is called when an error was detected during the 1091 * last packet command. We queue a request sense packet command in 1092 * the head of the request list. 1093 */ 1094static ide_startstop_t idetape_retry_pc (ide_drive_t *drive) 1095{ 1096 idetape_tape_t *tape = drive->driver_data; 1097 idetape_pc_t *pc; 1098 struct request *rq; 1099 1100 (void)ide_read_error(drive); 1101 pc = idetape_next_pc_storage(drive); 1102 rq = idetape_next_rq_storage(drive); 1103 idetape_create_request_sense_cmd(pc); 1104 set_bit(IDETAPE_IGNORE_DSC, &tape->flags); 1105 idetape_queue_pc_head(drive, pc, rq); 1106 return ide_stopped; 1107} 1108 1109/* 1110 * idetape_postpone_request postpones the current request so that 1111 * ide.c will be able to service requests from another device on 1112 * the same hwgroup while we are polling for DSC. 1113 */ 1114static void idetape_postpone_request (ide_drive_t *drive) 1115{ 1116 idetape_tape_t *tape = drive->driver_data; 1117 1118 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1119 1120 tape->postponed_rq = HWGROUP(drive)->rq; 1121 ide_stall_queue(drive, tape->dsc_polling_frequency); 1122} 1123 1124/* 1125 * idetape_pc_intr is the usual interrupt handler which will be called 1126 * during a packet command. We will transfer some of the data (as 1127 * requested by the drive) and will re-point interrupt handler to us. 1128 * When data transfer is finished, we will act according to the 1129 * algorithm described before idetape_issue_packet_command. 1130 * 1131 */ 1132static ide_startstop_t idetape_pc_intr (ide_drive_t *drive) 1133{ 1134 ide_hwif_t *hwif = drive->hwif; 1135 idetape_tape_t *tape = drive->driver_data; 1136 idetape_pc_t *pc = tape->pc; 1137 unsigned int temp; 1138#if SIMULATE_ERRORS 1139 static int error_sim_count = 0; 1140#endif 1141 u16 bcount; 1142 u8 stat, ireason; 1143 1144 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__); 1145 1146 /* Clear the interrupt */ 1147 stat = ide_read_status(drive); 1148 1149 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) { 1150 if (hwif->ide_dma_end(drive) || (stat & ERR_STAT)) { 1151 /* 1152 * A DMA error is sometimes expected. For example, 1153 * if the tape is crossing a filemark during a 1154 * READ command, it will issue an irq and position 1155 * itself before the filemark, so that only a partial 1156 * data transfer will occur (which causes the DMA 1157 * error). In that case, we will later ask the tape 1158 * how much bytes of the original request were 1159 * actually transferred (we can't receive that 1160 * information from the DMA engine on most chipsets). 1161 */ 1162 1163 /* 1164 * On the contrary, a DMA error is never expected; 1165 * it usually indicates a hardware error or abort. 1166 * If the tape crosses a filemark during a READ 1167 * command, it will issue an irq and position itself 1168 * after the filemark (not before). Only a partial 1169 * data transfer will occur, but no DMA error. 1170 * (AS, 19 Apr 2001) 1171 */ 1172 set_bit(PC_DMA_ERROR, &pc->flags); 1173 } else { 1174 pc->actually_transferred = pc->request_transfer; 1175 idetape_update_buffers(pc); 1176 } 1177 debug_log(DBG_PROCS, "DMA finished\n"); 1178 1179 } 1180 1181 /* No more interrupts */ 1182 if ((stat & DRQ_STAT) == 0) { 1183 debug_log(DBG_SENSE, "Packet command completed, %d bytes" 1184 " transferred\n", pc->actually_transferred); 1185 1186 clear_bit(PC_DMA_IN_PROGRESS, &pc->flags); 1187 local_irq_enable(); 1188 1189#if SIMULATE_ERRORS 1190 if ((pc->c[0] == WRITE_6 || pc->c[0] == READ_6) && 1191 (++error_sim_count % 100) == 0) { 1192 printk(KERN_INFO "ide-tape: %s: simulating error\n", 1193 tape->name); 1194 stat |= ERR_STAT; 1195 } 1196#endif 1197 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE) 1198 stat &= ~ERR_STAT; 1199 if ((stat & ERR_STAT) || test_bit(PC_DMA_ERROR, &pc->flags)) { 1200 /* Error detected */ 1201 debug_log(DBG_ERR, "%s: I/O error\n", tape->name); 1202 1203 if (pc->c[0] == REQUEST_SENSE) { 1204 printk(KERN_ERR "ide-tape: I/O error in request sense command\n"); 1205 return ide_do_reset(drive); 1206 } 1207 debug_log(DBG_ERR, "[cmd %x]: check condition\n", 1208 pc->c[0]); 1209 1210 /* Retry operation */ 1211 return idetape_retry_pc(drive); 1212 } 1213 pc->error = 0; 1214 if (test_bit(PC_WAIT_FOR_DSC, &pc->flags) && 1215 (stat & SEEK_STAT) == 0) { 1216 /* Media access command */ 1217 tape->dsc_polling_start = jiffies; 1218 tape->dsc_polling_frequency = IDETAPE_DSC_MA_FAST; 1219 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT; 1220 /* Allow ide.c to handle other requests */ 1221 idetape_postpone_request(drive); 1222 return ide_stopped; 1223 } 1224 if (tape->failed_pc == pc) 1225 tape->failed_pc = NULL; 1226 /* Command finished - Call the callback function */ 1227 return pc->callback(drive); 1228 } 1229 if (test_and_clear_bit(PC_DMA_IN_PROGRESS, &pc->flags)) { 1230 printk(KERN_ERR "ide-tape: The tape wants to issue more " 1231 "interrupts in DMA mode\n"); 1232 printk(KERN_ERR "ide-tape: DMA disabled, reverting to PIO\n"); 1233 ide_dma_off(drive); 1234 return ide_do_reset(drive); 1235 } 1236 /* Get the number of bytes to transfer on this interrupt. */ 1237 bcount = (hwif->INB(IDE_BCOUNTH_REG) << 8) | 1238 hwif->INB(IDE_BCOUNTL_REG); 1239 1240 ireason = hwif->INB(IDE_IREASON_REG); 1241 1242 if (ireason & CD) { 1243 printk(KERN_ERR "ide-tape: CoD != 0 in idetape_pc_intr\n"); 1244 return ide_do_reset(drive); 1245 } 1246 if (((ireason & IO) == IO) == test_bit(PC_WRITING, &pc->flags)) { 1247 /* Hopefully, we will never get here */ 1248 printk(KERN_ERR "ide-tape: We wanted to %s, ", 1249 (ireason & IO) ? "Write" : "Read"); 1250 printk(KERN_ERR "ide-tape: but the tape wants us to %s !\n", 1251 (ireason & IO) ? "Read" : "Write"); 1252 return ide_do_reset(drive); 1253 } 1254 if (!test_bit(PC_WRITING, &pc->flags)) { 1255 /* Reading - Check that we have enough space */ 1256 temp = pc->actually_transferred + bcount; 1257 if (temp > pc->request_transfer) { 1258 if (temp > pc->buffer_size) { 1259 printk(KERN_ERR "ide-tape: The tape wants to send us more data than expected - discarding data\n"); 1260 idetape_discard_data(drive, bcount); 1261 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 1262 return ide_started; 1263 } 1264 debug_log(DBG_SENSE, "The tape wants to send us more " 1265 "data than expected - allowing transfer\n"); 1266 1267 } 1268 } 1269 if (test_bit(PC_WRITING, &pc->flags)) { 1270 if (pc->bh != NULL) 1271 idetape_output_buffers(drive, pc, bcount); 1272 else 1273 /* Write the current buffer */ 1274 hwif->atapi_output_bytes(drive, pc->current_position, 1275 bcount); 1276 } else { 1277 if (pc->bh != NULL) 1278 idetape_input_buffers(drive, pc, bcount); 1279 else 1280 /* Read the current buffer */ 1281 hwif->atapi_input_bytes(drive, pc->current_position, 1282 bcount); 1283 } 1284 /* Update the current position */ 1285 pc->actually_transferred += bcount; 1286 pc->current_position += bcount; 1287 1288 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n", 1289 pc->c[0], bcount); 1290 1291 /* And set the interrupt handler again */ 1292 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 1293 return ide_started; 1294} 1295 1296/* 1297 * Packet Command Interface 1298 * 1299 * The current Packet Command is available in tape->pc, and will not 1300 * change until we finish handling it. Each packet command is associated 1301 * with a callback function that will be called when the command is 1302 * finished. 1303 * 1304 * The handling will be done in three stages: 1305 * 1306 * 1. idetape_issue_packet_command will send the packet command to the 1307 * drive, and will set the interrupt handler to idetape_pc_intr. 1308 * 1309 * 2. On each interrupt, idetape_pc_intr will be called. This step 1310 * will be repeated until the device signals us that no more 1311 * interrupts will be issued. 1312 * 1313 * 3. ATAPI Tape media access commands have immediate status with a 1314 * delayed process. In case of a successful initiation of a 1315 * media access packet command, the DSC bit will be set when the 1316 * actual execution of the command is finished. 1317 * Since the tape drive will not issue an interrupt, we have to 1318 * poll for this event. In this case, we define the request as 1319 * "low priority request" by setting rq_status to 1320 * IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and exit 1321 * the driver. 1322 * 1323 * ide.c will then give higher priority to requests which 1324 * originate from the other device, until will change rq_status 1325 * to RQ_ACTIVE. 1326 * 1327 * 4. When the packet command is finished, it will be checked for errors. 1328 * 1329 * 5. In case an error was found, we queue a request sense packet 1330 * command in front of the request queue and retry the operation 1331 * up to IDETAPE_MAX_PC_RETRIES times. 1332 * 1333 * 6. In case no error was found, or we decided to give up and not 1334 * to retry again, the callback function will be called and then 1335 * we will handle the next request. 1336 * 1337 */ 1338static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive) 1339{ 1340 ide_hwif_t *hwif = drive->hwif; 1341 idetape_tape_t *tape = drive->driver_data; 1342 idetape_pc_t *pc = tape->pc; 1343 int retries = 100; 1344 ide_startstop_t startstop; 1345 u8 ireason; 1346 1347 if (ide_wait_stat(&startstop,drive,DRQ_STAT,BUSY_STAT,WAIT_READY)) { 1348 printk(KERN_ERR "ide-tape: Strange, packet command initiated yet DRQ isn't asserted\n"); 1349 return startstop; 1350 } 1351 ireason = hwif->INB(IDE_IREASON_REG); 1352 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) { 1353 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while issuing " 1354 "a packet command, retrying\n"); 1355 udelay(100); 1356 ireason = hwif->INB(IDE_IREASON_REG); 1357 if (retries == 0) { 1358 printk(KERN_ERR "ide-tape: (IO,CoD != (0,1) while " 1359 "issuing a packet command, ignoring\n"); 1360 ireason |= CD; 1361 ireason &= ~IO; 1362 } 1363 } 1364 if ((ireason & CD) == 0 || (ireason & IO)) { 1365 printk(KERN_ERR "ide-tape: (IO,CoD) != (0,1) while issuing " 1366 "a packet command\n"); 1367 return ide_do_reset(drive); 1368 } 1369 /* Set the interrupt routine */ 1370 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL); 1371#ifdef CONFIG_BLK_DEV_IDEDMA 1372 /* Begin DMA, if necessary */ 1373 if (test_bit(PC_DMA_IN_PROGRESS, &pc->flags)) 1374 hwif->dma_start(drive); 1375#endif 1376 /* Send the actual packet */ 1377 HWIF(drive)->atapi_output_bytes(drive, pc->c, 12); 1378 return ide_started; 1379} 1380 1381static ide_startstop_t idetape_issue_packet_command (ide_drive_t *drive, idetape_pc_t *pc) 1382{ 1383 ide_hwif_t *hwif = drive->hwif; 1384 idetape_tape_t *tape = drive->driver_data; 1385 int dma_ok = 0; 1386 u16 bcount; 1387 1388 if (tape->pc->c[0] == REQUEST_SENSE && 1389 pc->c[0] == REQUEST_SENSE) { 1390 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - " 1391 "Two request sense in serial were issued\n"); 1392 } 1393 1394 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE) 1395 tape->failed_pc = pc; 1396 /* Set the current packet command */ 1397 tape->pc = pc; 1398 1399 if (pc->retries > IDETAPE_MAX_PC_RETRIES || 1400 test_bit(PC_ABORT, &pc->flags)) { 1401 /* 1402 * We will "abort" retrying a packet command in case 1403 * a legitimate error code was received (crossing a 1404 * filemark, or end of the media, for example). 1405 */ 1406 if (!test_bit(PC_ABORT, &pc->flags)) { 1407 if (!(pc->c[0] == TEST_UNIT_READY && 1408 tape->sense_key == 2 && tape->asc == 4 && 1409 (tape->ascq == 1 || tape->ascq == 8))) { 1410 printk(KERN_ERR "ide-tape: %s: I/O error, " 1411 "pc = %2x, key = %2x, " 1412 "asc = %2x, ascq = %2x\n", 1413 tape->name, pc->c[0], 1414 tape->sense_key, tape->asc, 1415 tape->ascq); 1416 } 1417 /* Giving up */ 1418 pc->error = IDETAPE_ERROR_GENERAL; 1419 } 1420 tape->failed_pc = NULL; 1421 return pc->callback(drive); 1422 } 1423 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]); 1424 1425 pc->retries++; 1426 /* We haven't transferred any data yet */ 1427 pc->actually_transferred = 0; 1428 pc->current_position = pc->buffer; 1429 /* Request to transfer the entire buffer at once */ 1430 bcount = pc->request_transfer; 1431 1432 if (test_and_clear_bit(PC_DMA_ERROR, &pc->flags)) { 1433 printk(KERN_WARNING "ide-tape: DMA disabled, " 1434 "reverting to PIO\n"); 1435 ide_dma_off(drive); 1436 } 1437 if (test_bit(PC_DMA_RECOMMENDED, &pc->flags) && drive->using_dma) 1438 dma_ok = !hwif->dma_setup(drive); 1439 1440 ide_pktcmd_tf_load(drive, IDE_TFLAG_NO_SELECT_MASK | 1441 IDE_TFLAG_OUT_DEVICE, bcount, dma_ok); 1442 1443 if (dma_ok) /* Will begin DMA later */ 1444 set_bit(PC_DMA_IN_PROGRESS, &pc->flags); 1445 if (test_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags)) { 1446 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc, 1447 IDETAPE_WAIT_CMD, NULL); 1448 return ide_started; 1449 } else { 1450 hwif->OUTB(WIN_PACKETCMD, IDE_COMMAND_REG); 1451 return idetape_transfer_pc(drive); 1452 } 1453} 1454 1455/* 1456 * General packet command callback function. 1457 */ 1458static ide_startstop_t idetape_pc_callback (ide_drive_t *drive) 1459{ 1460 idetape_tape_t *tape = drive->driver_data; 1461 1462 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1463 1464 idetape_end_request(drive, tape->pc->error ? 0 : 1, 0); 1465 return ide_stopped; 1466} 1467 1468/* 1469 * A mode sense command is used to "sense" tape parameters. 1470 */ 1471static void idetape_create_mode_sense_cmd (idetape_pc_t *pc, u8 page_code) 1472{ 1473 idetape_init_pc(pc); 1474 pc->c[0] = MODE_SENSE; 1475 if (page_code != IDETAPE_BLOCK_DESCRIPTOR) 1476 pc->c[1] = 8; /* DBD = 1 - Don't return block descriptors */ 1477 pc->c[2] = page_code; 1478 /* 1479 * Changed pc->c[3] to 0 (255 will at best return unused info). 1480 * 1481 * For SCSI this byte is defined as subpage instead of high byte 1482 * of length and some IDE drives seem to interpret it this way 1483 * and return an error when 255 is used. 1484 */ 1485 pc->c[3] = 0; 1486 pc->c[4] = 255; /* (We will just discard data in that case) */ 1487 if (page_code == IDETAPE_BLOCK_DESCRIPTOR) 1488 pc->request_transfer = 12; 1489 else if (page_code == IDETAPE_CAPABILITIES_PAGE) 1490 pc->request_transfer = 24; 1491 else 1492 pc->request_transfer = 50; 1493 pc->callback = &idetape_pc_callback; 1494} 1495 1496static void calculate_speeds(ide_drive_t *drive) 1497{ 1498 idetape_tape_t *tape = drive->driver_data; 1499 int full = 125, empty = 75; 1500 1501 if (time_after(jiffies, tape->controlled_pipeline_head_time + 120 * HZ)) { 1502 tape->controlled_previous_pipeline_head = tape->controlled_last_pipeline_head; 1503 tape->controlled_previous_head_time = tape->controlled_pipeline_head_time; 1504 tape->controlled_last_pipeline_head = tape->pipeline_head; 1505 tape->controlled_pipeline_head_time = jiffies; 1506 } 1507 if (time_after(jiffies, tape->controlled_pipeline_head_time + 60 * HZ)) 1508 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_last_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_pipeline_head_time); 1509 else if (time_after(jiffies, tape->controlled_previous_head_time)) 1510 tape->controlled_pipeline_head_speed = (tape->pipeline_head - tape->controlled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->controlled_previous_head_time); 1511 1512 if (tape->nr_pending_stages < tape->max_stages /*- 1 */) { 1513 /* -1 for read mode error recovery */ 1514 if (time_after(jiffies, tape->uncontrolled_previous_head_time + 10 * HZ)) { 1515 tape->uncontrolled_pipeline_head_time = jiffies; 1516 tape->uncontrolled_pipeline_head_speed = (tape->pipeline_head - tape->uncontrolled_previous_pipeline_head) * 32 * HZ / (jiffies - tape->uncontrolled_previous_head_time); 1517 } 1518 } else { 1519 tape->uncontrolled_previous_head_time = jiffies; 1520 tape->uncontrolled_previous_pipeline_head = tape->pipeline_head; 1521 if (time_after(jiffies, tape->uncontrolled_pipeline_head_time + 30 * HZ)) { 1522 tape->uncontrolled_pipeline_head_time = jiffies; 1523 } 1524 } 1525 tape->pipeline_head_speed = max(tape->uncontrolled_pipeline_head_speed, tape->controlled_pipeline_head_speed); 1526 if (tape->speed_control == 0) { 1527 tape->max_insert_speed = 5000; 1528 } else if (tape->speed_control == 1) { 1529 if (tape->nr_pending_stages >= tape->max_stages / 2) 1530 tape->max_insert_speed = tape->pipeline_head_speed + 1531 (1100 - tape->pipeline_head_speed) * 2 * (tape->nr_pending_stages - tape->max_stages / 2) / tape->max_stages; 1532 else 1533 tape->max_insert_speed = 500 + 1534 (tape->pipeline_head_speed - 500) * 2 * tape->nr_pending_stages / tape->max_stages; 1535 if (tape->nr_pending_stages >= tape->max_stages * 99 / 100) 1536 tape->max_insert_speed = 5000; 1537 } else if (tape->speed_control == 2) { 1538 tape->max_insert_speed = tape->pipeline_head_speed * empty / 100 + 1539 (tape->pipeline_head_speed * full / 100 - tape->pipeline_head_speed * empty / 100) * tape->nr_pending_stages / tape->max_stages; 1540 } else 1541 tape->max_insert_speed = tape->speed_control; 1542 tape->max_insert_speed = max(tape->max_insert_speed, 500); 1543} 1544 1545static ide_startstop_t idetape_media_access_finished (ide_drive_t *drive) 1546{ 1547 idetape_tape_t *tape = drive->driver_data; 1548 idetape_pc_t *pc = tape->pc; 1549 u8 stat; 1550 1551 stat = ide_read_status(drive); 1552 1553 if (stat & SEEK_STAT) { 1554 if (stat & ERR_STAT) { 1555 /* Error detected */ 1556 if (pc->c[0] != TEST_UNIT_READY) 1557 printk(KERN_ERR "ide-tape: %s: I/O error, ", 1558 tape->name); 1559 /* Retry operation */ 1560 return idetape_retry_pc(drive); 1561 } 1562 pc->error = 0; 1563 if (tape->failed_pc == pc) 1564 tape->failed_pc = NULL; 1565 } else { 1566 pc->error = IDETAPE_ERROR_GENERAL; 1567 tape->failed_pc = NULL; 1568 } 1569 return pc->callback(drive); 1570} 1571 1572static ide_startstop_t idetape_rw_callback (ide_drive_t *drive) 1573{ 1574 idetape_tape_t *tape = drive->driver_data; 1575 struct request *rq = HWGROUP(drive)->rq; 1576 int blocks = tape->pc->actually_transferred / tape->tape_block_size; 1577 1578 tape->avg_size += blocks * tape->tape_block_size; 1579 tape->insert_size += blocks * tape->tape_block_size; 1580 if (tape->insert_size > 1024 * 1024) 1581 tape->measure_insert_time = 1; 1582 if (tape->measure_insert_time) { 1583 tape->measure_insert_time = 0; 1584 tape->insert_time = jiffies; 1585 tape->insert_size = 0; 1586 } 1587 if (time_after(jiffies, tape->insert_time)) 1588 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time); 1589 if (time_after_eq(jiffies, tape->avg_time + HZ)) { 1590 tape->avg_speed = tape->avg_size * HZ / (jiffies - tape->avg_time) / 1024; 1591 tape->avg_size = 0; 1592 tape->avg_time = jiffies; 1593 } 1594 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1595 1596 tape->first_frame_position += blocks; 1597 rq->current_nr_sectors -= blocks; 1598 1599 if (!tape->pc->error) 1600 idetape_end_request(drive, 1, 0); 1601 else 1602 idetape_end_request(drive, tape->pc->error, 0); 1603 return ide_stopped; 1604} 1605 1606static void idetape_create_read_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh) 1607{ 1608 idetape_init_pc(pc); 1609 pc->c[0] = READ_6; 1610 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1611 pc->c[1] = 1; 1612 pc->callback = &idetape_rw_callback; 1613 pc->bh = bh; 1614 atomic_set(&bh->b_count, 0); 1615 pc->buffer = NULL; 1616 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size; 1617 if (pc->request_transfer == tape->stage_size) 1618 set_bit(PC_DMA_RECOMMENDED, &pc->flags); 1619} 1620 1621static void idetape_create_read_buffer_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh) 1622{ 1623 int size = 32768; 1624 struct idetape_bh *p = bh; 1625 1626 idetape_init_pc(pc); 1627 pc->c[0] = READ_BUFFER; 1628 pc->c[1] = IDETAPE_RETRIEVE_FAULTY_BLOCK; 1629 pc->c[7] = size >> 8; 1630 pc->c[8] = size & 0xff; 1631 pc->callback = &idetape_pc_callback; 1632 pc->bh = bh; 1633 atomic_set(&bh->b_count, 0); 1634 pc->buffer = NULL; 1635 while (p) { 1636 atomic_set(&p->b_count, 0); 1637 p = p->b_reqnext; 1638 } 1639 pc->request_transfer = pc->buffer_size = size; 1640} 1641 1642static void idetape_create_write_cmd(idetape_tape_t *tape, idetape_pc_t *pc, unsigned int length, struct idetape_bh *bh) 1643{ 1644 idetape_init_pc(pc); 1645 pc->c[0] = WRITE_6; 1646 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]); 1647 pc->c[1] = 1; 1648 pc->callback = &idetape_rw_callback; 1649 set_bit(PC_WRITING, &pc->flags); 1650 pc->bh = bh; 1651 pc->b_data = bh->b_data; 1652 pc->b_count = atomic_read(&bh->b_count); 1653 pc->buffer = NULL; 1654 pc->request_transfer = pc->buffer_size = length * tape->tape_block_size; 1655 if (pc->request_transfer == tape->stage_size) 1656 set_bit(PC_DMA_RECOMMENDED, &pc->flags); 1657} 1658 1659/* 1660 * idetape_do_request is our request handling function. 1661 */ 1662static ide_startstop_t idetape_do_request(ide_drive_t *drive, 1663 struct request *rq, sector_t block) 1664{ 1665 idetape_tape_t *tape = drive->driver_data; 1666 idetape_pc_t *pc = NULL; 1667 struct request *postponed_rq = tape->postponed_rq; 1668 u8 stat; 1669 1670 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld," 1671 " current_nr_sectors: %d\n", 1672 rq->sector, rq->nr_sectors, rq->current_nr_sectors); 1673 1674 if (!blk_special_request(rq)) { 1675 /* 1676 * We do not support buffer cache originated requests. 1677 */ 1678 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in " 1679 "request queue (%d)\n", drive->name, rq->cmd_type); 1680 ide_end_request(drive, 0, 0); 1681 return ide_stopped; 1682 } 1683 1684 /* 1685 * Retry a failed packet command 1686 */ 1687 if (tape->failed_pc != NULL && 1688 tape->pc->c[0] == REQUEST_SENSE) { 1689 return idetape_issue_packet_command(drive, tape->failed_pc); 1690 } 1691 if (postponed_rq != NULL) 1692 if (rq != postponed_rq) { 1693 printk(KERN_ERR "ide-tape: ide-tape.c bug - " 1694 "Two DSC requests were queued\n"); 1695 idetape_end_request(drive, 0, 0); 1696 return ide_stopped; 1697 } 1698 1699 tape->postponed_rq = NULL; 1700 1701 /* 1702 * If the tape is still busy, postpone our request and service 1703 * the other device meanwhile. 1704 */ 1705 stat = ide_read_status(drive); 1706 1707 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2)) 1708 set_bit(IDETAPE_IGNORE_DSC, &tape->flags); 1709 1710 if (drive->post_reset == 1) { 1711 set_bit(IDETAPE_IGNORE_DSC, &tape->flags); 1712 drive->post_reset = 0; 1713 } 1714 1715 if (tape->tape_still_time > 100 && tape->tape_still_time < 200) 1716 tape->measure_insert_time = 1; 1717 if (time_after(jiffies, tape->insert_time)) 1718 tape->insert_speed = tape->insert_size / 1024 * HZ / (jiffies - tape->insert_time); 1719 calculate_speeds(drive); 1720 if (!test_and_clear_bit(IDETAPE_IGNORE_DSC, &tape->flags) && 1721 (stat & SEEK_STAT) == 0) { 1722 if (postponed_rq == NULL) { 1723 tape->dsc_polling_start = jiffies; 1724 tape->dsc_polling_frequency = tape->best_dsc_rw_frequency; 1725 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT; 1726 } else if (time_after(jiffies, tape->dsc_timeout)) { 1727 printk(KERN_ERR "ide-tape: %s: DSC timeout\n", 1728 tape->name); 1729 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1730 idetape_media_access_finished(drive); 1731 return ide_stopped; 1732 } else { 1733 return ide_do_reset(drive); 1734 } 1735 } else if (time_after(jiffies, tape->dsc_polling_start + IDETAPE_DSC_MA_THRESHOLD)) 1736 tape->dsc_polling_frequency = IDETAPE_DSC_MA_SLOW; 1737 idetape_postpone_request(drive); 1738 return ide_stopped; 1739 } 1740 if (rq->cmd[0] & REQ_IDETAPE_READ) { 1741 tape->buffer_head++; 1742 tape->postpone_cnt = 0; 1743 pc = idetape_next_pc_storage(drive); 1744 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special); 1745 goto out; 1746 } 1747 if (rq->cmd[0] & REQ_IDETAPE_WRITE) { 1748 tape->buffer_head++; 1749 tape->postpone_cnt = 0; 1750 pc = idetape_next_pc_storage(drive); 1751 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special); 1752 goto out; 1753 } 1754 if (rq->cmd[0] & REQ_IDETAPE_READ_BUFFER) { 1755 tape->postpone_cnt = 0; 1756 pc = idetape_next_pc_storage(drive); 1757 idetape_create_read_buffer_cmd(tape, pc, rq->current_nr_sectors, (struct idetape_bh *)rq->special); 1758 goto out; 1759 } 1760 if (rq->cmd[0] & REQ_IDETAPE_PC1) { 1761 pc = (idetape_pc_t *) rq->buffer; 1762 rq->cmd[0] &= ~(REQ_IDETAPE_PC1); 1763 rq->cmd[0] |= REQ_IDETAPE_PC2; 1764 goto out; 1765 } 1766 if (rq->cmd[0] & REQ_IDETAPE_PC2) { 1767 idetape_media_access_finished(drive); 1768 return ide_stopped; 1769 } 1770 BUG(); 1771out: 1772 return idetape_issue_packet_command(drive, pc); 1773} 1774 1775/* 1776 * Pipeline related functions 1777 */ 1778static inline int idetape_pipeline_active (idetape_tape_t *tape) 1779{ 1780 int rc1, rc2; 1781 1782 rc1 = test_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags); 1783 rc2 = (tape->active_data_request != NULL); 1784 return rc1; 1785} 1786 1787/* 1788 * idetape_kmalloc_stage uses __get_free_page to allocate a pipeline 1789 * stage, along with all the necessary small buffers which together make 1790 * a buffer of size tape->stage_size (or a bit more). We attempt to 1791 * combine sequential pages as much as possible. 1792 * 1793 * Returns a pointer to the new allocated stage, or NULL if we 1794 * can't (or don't want to) allocate a stage. 1795 * 1796 * Pipeline stages are optional and are used to increase performance. 1797 * If we can't allocate them, we'll manage without them. 1798 */ 1799static idetape_stage_t *__idetape_kmalloc_stage (idetape_tape_t *tape, int full, int clear) 1800{ 1801 idetape_stage_t *stage; 1802 struct idetape_bh *prev_bh, *bh; 1803 int pages = tape->pages_per_stage; 1804 char *b_data = NULL; 1805 1806 if ((stage = kmalloc(sizeof (idetape_stage_t),GFP_KERNEL)) == NULL) 1807 return NULL; 1808 stage->next = NULL; 1809 1810 bh = stage->bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL); 1811 if (bh == NULL) 1812 goto abort; 1813 bh->b_reqnext = NULL; 1814 if ((bh->b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL) 1815 goto abort; 1816 if (clear) 1817 memset(bh->b_data, 0, PAGE_SIZE); 1818 bh->b_size = PAGE_SIZE; 1819 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1820 1821 while (--pages) { 1822 if ((b_data = (char *) __get_free_page (GFP_KERNEL)) == NULL) 1823 goto abort; 1824 if (clear) 1825 memset(b_data, 0, PAGE_SIZE); 1826 if (bh->b_data == b_data + PAGE_SIZE) { 1827 bh->b_size += PAGE_SIZE; 1828 bh->b_data -= PAGE_SIZE; 1829 if (full) 1830 atomic_add(PAGE_SIZE, &bh->b_count); 1831 continue; 1832 } 1833 if (b_data == bh->b_data + bh->b_size) { 1834 bh->b_size += PAGE_SIZE; 1835 if (full) 1836 atomic_add(PAGE_SIZE, &bh->b_count); 1837 continue; 1838 } 1839 prev_bh = bh; 1840 if ((bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL)) == NULL) { 1841 free_page((unsigned long) b_data); 1842 goto abort; 1843 } 1844 bh->b_reqnext = NULL; 1845 bh->b_data = b_data; 1846 bh->b_size = PAGE_SIZE; 1847 atomic_set(&bh->b_count, full ? bh->b_size : 0); 1848 prev_bh->b_reqnext = bh; 1849 } 1850 bh->b_size -= tape->excess_bh_size; 1851 if (full) 1852 atomic_sub(tape->excess_bh_size, &bh->b_count); 1853 return stage; 1854abort: 1855 __idetape_kfree_stage(stage); 1856 return NULL; 1857} 1858 1859static idetape_stage_t *idetape_kmalloc_stage (idetape_tape_t *tape) 1860{ 1861 idetape_stage_t *cache_stage = tape->cache_stage; 1862 1863 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1864 1865 if (tape->nr_stages >= tape->max_stages) 1866 return NULL; 1867 if (cache_stage != NULL) { 1868 tape->cache_stage = NULL; 1869 return cache_stage; 1870 } 1871 return __idetape_kmalloc_stage(tape, 0, 0); 1872} 1873 1874static int idetape_copy_stage_from_user (idetape_tape_t *tape, idetape_stage_t *stage, const char __user *buf, int n) 1875{ 1876 struct idetape_bh *bh = tape->bh; 1877 int count; 1878 int ret = 0; 1879 1880 while (n) { 1881 if (bh == NULL) { 1882 printk(KERN_ERR "ide-tape: bh == NULL in " 1883 "idetape_copy_stage_from_user\n"); 1884 return 1; 1885 } 1886 count = min((unsigned int)(bh->b_size - atomic_read(&bh->b_count)), (unsigned int)n); 1887 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf, count)) 1888 ret = 1; 1889 n -= count; 1890 atomic_add(count, &bh->b_count); 1891 buf += count; 1892 if (atomic_read(&bh->b_count) == bh->b_size) { 1893 bh = bh->b_reqnext; 1894 if (bh) 1895 atomic_set(&bh->b_count, 0); 1896 } 1897 } 1898 tape->bh = bh; 1899 return ret; 1900} 1901 1902static int idetape_copy_stage_to_user (idetape_tape_t *tape, char __user *buf, idetape_stage_t *stage, int n) 1903{ 1904 struct idetape_bh *bh = tape->bh; 1905 int count; 1906 int ret = 0; 1907 1908 while (n) { 1909 if (bh == NULL) { 1910 printk(KERN_ERR "ide-tape: bh == NULL in " 1911 "idetape_copy_stage_to_user\n"); 1912 return 1; 1913 } 1914 count = min(tape->b_count, n); 1915 if (copy_to_user(buf, tape->b_data, count)) 1916 ret = 1; 1917 n -= count; 1918 tape->b_data += count; 1919 tape->b_count -= count; 1920 buf += count; 1921 if (!tape->b_count) { 1922 tape->bh = bh = bh->b_reqnext; 1923 if (bh) { 1924 tape->b_data = bh->b_data; 1925 tape->b_count = atomic_read(&bh->b_count); 1926 } 1927 } 1928 } 1929 return ret; 1930} 1931 1932static void idetape_init_merge_stage (idetape_tape_t *tape) 1933{ 1934 struct idetape_bh *bh = tape->merge_stage->bh; 1935 1936 tape->bh = bh; 1937 if (tape->chrdev_direction == idetape_direction_write) 1938 atomic_set(&bh->b_count, 0); 1939 else { 1940 tape->b_data = bh->b_data; 1941 tape->b_count = atomic_read(&bh->b_count); 1942 } 1943} 1944 1945static void idetape_switch_buffers (idetape_tape_t *tape, idetape_stage_t *stage) 1946{ 1947 struct idetape_bh *tmp; 1948 1949 tmp = stage->bh; 1950 stage->bh = tape->merge_stage->bh; 1951 tape->merge_stage->bh = tmp; 1952 idetape_init_merge_stage(tape); 1953} 1954 1955/* 1956 * idetape_add_stage_tail adds a new stage at the end of the pipeline. 1957 */ 1958static void idetape_add_stage_tail (ide_drive_t *drive,idetape_stage_t *stage) 1959{ 1960 idetape_tape_t *tape = drive->driver_data; 1961 unsigned long flags; 1962 1963 debug_log(DBG_PROCS, "Enter %s\n", __func__); 1964 1965 spin_lock_irqsave(&tape->spinlock, flags); 1966 stage->next = NULL; 1967 if (tape->last_stage != NULL) 1968 tape->last_stage->next=stage; 1969 else 1970 tape->first_stage = tape->next_stage=stage; 1971 tape->last_stage = stage; 1972 if (tape->next_stage == NULL) 1973 tape->next_stage = tape->last_stage; 1974 tape->nr_stages++; 1975 tape->nr_pending_stages++; 1976 spin_unlock_irqrestore(&tape->spinlock, flags); 1977} 1978 1979/* 1980 * idetape_wait_for_request installs a completion in a pending request 1981 * and sleeps until it is serviced. 1982 * 1983 * The caller should ensure that the request will not be serviced 1984 * before we install the completion (usually by disabling interrupts). 1985 */ 1986static void idetape_wait_for_request (ide_drive_t *drive, struct request *rq) 1987{ 1988 DECLARE_COMPLETION_ONSTACK(wait); 1989 idetape_tape_t *tape = drive->driver_data; 1990 1991 if (rq == NULL || !blk_special_request(rq)) { 1992 printk (KERN_ERR "ide-tape: bug: Trying to sleep on non-valid request\n"); 1993 return; 1994 } 1995 rq->end_io_data = &wait; 1996 rq->end_io = blk_end_sync_rq; 1997 spin_unlock_irq(&tape->spinlock); 1998 wait_for_completion(&wait); 1999 /* The stage and its struct request have been deallocated */ 2000 spin_lock_irq(&tape->spinlock); 2001} 2002 2003static ide_startstop_t idetape_read_position_callback (ide_drive_t *drive) 2004{ 2005 idetape_tape_t *tape = drive->driver_data; 2006 idetape_read_position_result_t *result; 2007 2008 debug_log(DBG_PROCS, "Enter %s\n", __func__); 2009 2010 if (!tape->pc->error) { 2011 result = (idetape_read_position_result_t *) tape->pc->buffer; 2012 debug_log(DBG_SENSE, "BOP - %s\n", result->bop ? "Yes" : "No"); 2013 debug_log(DBG_SENSE, "EOP - %s\n", result->eop ? "Yes" : "No"); 2014 2015 if (result->bpu) { 2016 printk(KERN_INFO "ide-tape: Block location is unknown to the tape\n"); 2017 clear_bit(IDETAPE_ADDRESS_VALID, &tape->flags); 2018 idetape_end_request(drive, 0, 0); 2019 } else { 2020 debug_log(DBG_SENSE, "Block Location - %u\n", 2021 ntohl(result->first_block)); 2022 2023 tape->partition = result->partition; 2024 tape->first_frame_position = ntohl(result->first_block); 2025 tape->last_frame_position = ntohl(result->last_block); 2026 tape->blocks_in_buffer = result->blocks_in_buffer[2]; 2027 set_bit(IDETAPE_ADDRESS_VALID, &tape->flags); 2028 idetape_end_request(drive, 1, 0); 2029 } 2030 } else { 2031 idetape_end_request(drive, 0, 0); 2032 } 2033 return ide_stopped; 2034} 2035 2036/* 2037 * idetape_create_write_filemark_cmd will: 2038 * 2039 * 1. Write a filemark if write_filemark=1. 2040 * 2. Flush the device buffers without writing a filemark 2041 * if write_filemark=0. 2042 * 2043 */ 2044static void idetape_create_write_filemark_cmd (ide_drive_t *drive, idetape_pc_t *pc,int write_filemark) 2045{ 2046 idetape_init_pc(pc); 2047 pc->c[0] = WRITE_FILEMARKS; 2048 pc->c[4] = write_filemark; 2049 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2050 pc->callback = &idetape_pc_callback; 2051} 2052 2053static void idetape_create_test_unit_ready_cmd(idetape_pc_t *pc) 2054{ 2055 idetape_init_pc(pc); 2056 pc->c[0] = TEST_UNIT_READY; 2057 pc->callback = &idetape_pc_callback; 2058} 2059 2060/* 2061 * idetape_queue_pc_tail is based on the following functions: 2062 * 2063 * ide_do_drive_cmd from ide.c 2064 * cdrom_queue_request and cdrom_queue_packet_command from ide-cd.c 2065 * 2066 * We add a special packet command request to the tail of the request 2067 * queue, and wait for it to be serviced. 2068 * 2069 * This is not to be called from within the request handling part 2070 * of the driver ! We allocate here data in the stack, and it is valid 2071 * until the request is finished. This is not the case for the bottom 2072 * part of the driver, where we are always leaving the functions to wait 2073 * for an interrupt or a timer event. 2074 * 2075 * From the bottom part of the driver, we should allocate safe memory 2076 * using idetape_next_pc_storage and idetape_next_rq_storage, and add 2077 * the request to the request list without waiting for it to be serviced ! 2078 * In that case, we usually use idetape_queue_pc_head. 2079 */ 2080static int __idetape_queue_pc_tail (ide_drive_t *drive, idetape_pc_t *pc) 2081{ 2082 struct ide_tape_obj *tape = drive->driver_data; 2083 struct request rq; 2084 2085 idetape_init_rq(&rq, REQ_IDETAPE_PC1); 2086 rq.buffer = (char *) pc; 2087 rq.rq_disk = tape->disk; 2088 return ide_do_drive_cmd(drive, &rq, ide_wait); 2089} 2090 2091static void idetape_create_load_unload_cmd (ide_drive_t *drive, idetape_pc_t *pc,int cmd) 2092{ 2093 idetape_init_pc(pc); 2094 pc->c[0] = START_STOP; 2095 pc->c[4] = cmd; 2096 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2097 pc->callback = &idetape_pc_callback; 2098} 2099 2100static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout) 2101{ 2102 idetape_tape_t *tape = drive->driver_data; 2103 idetape_pc_t pc; 2104 int load_attempted = 0; 2105 2106 /* 2107 * Wait for the tape to become ready 2108 */ 2109 set_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags); 2110 timeout += jiffies; 2111 while (time_before(jiffies, timeout)) { 2112 idetape_create_test_unit_ready_cmd(&pc); 2113 if (!__idetape_queue_pc_tail(drive, &pc)) 2114 return 0; 2115 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2) 2116 || (tape->asc == 0x3A)) { /* no media */ 2117 if (load_attempted) 2118 return -ENOMEDIUM; 2119 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK); 2120 __idetape_queue_pc_tail(drive, &pc); 2121 load_attempted = 1; 2122 /* not about to be ready */ 2123 } else if (!(tape->sense_key == 2 && tape->asc == 4 && 2124 (tape->ascq == 1 || tape->ascq == 8))) 2125 return -EIO; 2126 msleep(100); 2127 } 2128 return -EIO; 2129} 2130 2131static int idetape_queue_pc_tail (ide_drive_t *drive,idetape_pc_t *pc) 2132{ 2133 return __idetape_queue_pc_tail(drive, pc); 2134} 2135 2136static int idetape_flush_tape_buffers (ide_drive_t *drive) 2137{ 2138 idetape_pc_t pc; 2139 int rc; 2140 2141 idetape_create_write_filemark_cmd(drive, &pc, 0); 2142 if ((rc = idetape_queue_pc_tail(drive, &pc))) 2143 return rc; 2144 idetape_wait_ready(drive, 60 * 5 * HZ); 2145 return 0; 2146} 2147 2148static void idetape_create_read_position_cmd (idetape_pc_t *pc) 2149{ 2150 idetape_init_pc(pc); 2151 pc->c[0] = READ_POSITION; 2152 pc->request_transfer = 20; 2153 pc->callback = &idetape_read_position_callback; 2154} 2155 2156static int idetape_read_position (ide_drive_t *drive) 2157{ 2158 idetape_tape_t *tape = drive->driver_data; 2159 idetape_pc_t pc; 2160 int position; 2161 2162 debug_log(DBG_PROCS, "Enter %s\n", __func__); 2163 2164 idetape_create_read_position_cmd(&pc); 2165 if (idetape_queue_pc_tail(drive, &pc)) 2166 return -1; 2167 position = tape->first_frame_position; 2168 return position; 2169} 2170 2171static void idetape_create_locate_cmd (ide_drive_t *drive, idetape_pc_t *pc, unsigned int block, u8 partition, int skip) 2172{ 2173 idetape_init_pc(pc); 2174 pc->c[0] = POSITION_TO_ELEMENT; 2175 pc->c[1] = 2; 2176 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]); 2177 pc->c[8] = partition; 2178 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2179 pc->callback = &idetape_pc_callback; 2180} 2181 2182static int idetape_create_prevent_cmd (ide_drive_t *drive, idetape_pc_t *pc, int prevent) 2183{ 2184 idetape_tape_t *tape = drive->driver_data; 2185 2186 /* device supports locking according to capabilities page */ 2187 if (!(tape->caps[6] & 0x01)) 2188 return 0; 2189 2190 idetape_init_pc(pc); 2191 pc->c[0] = ALLOW_MEDIUM_REMOVAL; 2192 pc->c[4] = prevent; 2193 pc->callback = &idetape_pc_callback; 2194 return 1; 2195} 2196 2197static int __idetape_discard_read_pipeline (ide_drive_t *drive) 2198{ 2199 idetape_tape_t *tape = drive->driver_data; 2200 unsigned long flags; 2201 int cnt; 2202 2203 if (tape->chrdev_direction != idetape_direction_read) 2204 return 0; 2205 2206 /* Remove merge stage. */ 2207 cnt = tape->merge_stage_size / tape->tape_block_size; 2208 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags)) 2209 ++cnt; /* Filemarks count as 1 sector */ 2210 tape->merge_stage_size = 0; 2211 if (tape->merge_stage != NULL) { 2212 __idetape_kfree_stage(tape->merge_stage); 2213 tape->merge_stage = NULL; 2214 } 2215 2216 /* Clear pipeline flags. */ 2217 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 2218 tape->chrdev_direction = idetape_direction_none; 2219 2220 /* Remove pipeline stages. */ 2221 if (tape->first_stage == NULL) 2222 return 0; 2223 2224 spin_lock_irqsave(&tape->spinlock, flags); 2225 tape->next_stage = NULL; 2226 if (idetape_pipeline_active(tape)) 2227 idetape_wait_for_request(drive, tape->active_data_request); 2228 spin_unlock_irqrestore(&tape->spinlock, flags); 2229 2230 while (tape->first_stage != NULL) { 2231 struct request *rq_ptr = &tape->first_stage->rq; 2232 2233 cnt += rq_ptr->nr_sectors - rq_ptr->current_nr_sectors; 2234 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK) 2235 ++cnt; 2236 idetape_remove_stage_head(drive); 2237 } 2238 tape->nr_pending_stages = 0; 2239 tape->max_stages = tape->min_pipeline; 2240 return cnt; 2241} 2242 2243/* 2244 * idetape_position_tape positions the tape to the requested block 2245 * using the LOCATE packet command. A READ POSITION command is then 2246 * issued to check where we are positioned. 2247 * 2248 * Like all higher level operations, we queue the commands at the tail 2249 * of the request queue and wait for their completion. 2250 * 2251 */ 2252static int idetape_position_tape (ide_drive_t *drive, unsigned int block, u8 partition, int skip) 2253{ 2254 idetape_tape_t *tape = drive->driver_data; 2255 int retval; 2256 idetape_pc_t pc; 2257 2258 if (tape->chrdev_direction == idetape_direction_read) 2259 __idetape_discard_read_pipeline(drive); 2260 idetape_wait_ready(drive, 60 * 5 * HZ); 2261 idetape_create_locate_cmd(drive, &pc, block, partition, skip); 2262 retval = idetape_queue_pc_tail(drive, &pc); 2263 if (retval) 2264 return (retval); 2265 2266 idetape_create_read_position_cmd(&pc); 2267 return (idetape_queue_pc_tail(drive, &pc)); 2268} 2269 2270static void idetape_discard_read_pipeline (ide_drive_t *drive, int restore_position) 2271{ 2272 idetape_tape_t *tape = drive->driver_data; 2273 int cnt; 2274 int seek, position; 2275 2276 cnt = __idetape_discard_read_pipeline(drive); 2277 if (restore_position) { 2278 position = idetape_read_position(drive); 2279 seek = position > cnt ? position - cnt : 0; 2280 if (idetape_position_tape(drive, seek, 0, 0)) { 2281 printk(KERN_INFO "ide-tape: %s: position_tape failed in discard_pipeline()\n", tape->name); 2282 return; 2283 } 2284 } 2285} 2286 2287/* 2288 * idetape_queue_rw_tail generates a read/write request for the block 2289 * device interface and wait for it to be serviced. 2290 */ 2291static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks, struct idetape_bh *bh) 2292{ 2293 idetape_tape_t *tape = drive->driver_data; 2294 struct request rq; 2295 2296 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd); 2297 2298 if (idetape_pipeline_active(tape)) { 2299 printk(KERN_ERR "ide-tape: bug: the pipeline is active in %s\n", 2300 __func__); 2301 return (0); 2302 } 2303 2304 idetape_init_rq(&rq, cmd); 2305 rq.rq_disk = tape->disk; 2306 rq.special = (void *)bh; 2307 rq.sector = tape->first_frame_position; 2308 rq.nr_sectors = rq.current_nr_sectors = blocks; 2309 (void) ide_do_drive_cmd(drive, &rq, ide_wait); 2310 2311 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0) 2312 return 0; 2313 2314 if (tape->merge_stage) 2315 idetape_init_merge_stage(tape); 2316 if (rq.errors == IDETAPE_ERROR_GENERAL) 2317 return -EIO; 2318 return (tape->tape_block_size * (blocks-rq.current_nr_sectors)); 2319} 2320 2321/* 2322 * idetape_insert_pipeline_into_queue is used to start servicing the 2323 * pipeline stages, starting from tape->next_stage. 2324 */ 2325static void idetape_insert_pipeline_into_queue (ide_drive_t *drive) 2326{ 2327 idetape_tape_t *tape = drive->driver_data; 2328 2329 if (tape->next_stage == NULL) 2330 return; 2331 if (!idetape_pipeline_active(tape)) { 2332 set_bit(IDETAPE_PIPELINE_ACTIVE, &tape->flags); 2333 idetape_activate_next_stage(drive); 2334 (void) ide_do_drive_cmd(drive, tape->active_data_request, ide_end); 2335 } 2336} 2337 2338static void idetape_create_inquiry_cmd (idetape_pc_t *pc) 2339{ 2340 idetape_init_pc(pc); 2341 pc->c[0] = INQUIRY; 2342 pc->c[4] = pc->request_transfer = 254; 2343 pc->callback = &idetape_pc_callback; 2344} 2345 2346static void idetape_create_rewind_cmd (ide_drive_t *drive, idetape_pc_t *pc) 2347{ 2348 idetape_init_pc(pc); 2349 pc->c[0] = REZERO_UNIT; 2350 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2351 pc->callback = &idetape_pc_callback; 2352} 2353 2354static void idetape_create_erase_cmd (idetape_pc_t *pc) 2355{ 2356 idetape_init_pc(pc); 2357 pc->c[0] = ERASE; 2358 pc->c[1] = 1; 2359 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2360 pc->callback = &idetape_pc_callback; 2361} 2362 2363static void idetape_create_space_cmd (idetape_pc_t *pc,int count, u8 cmd) 2364{ 2365 idetape_init_pc(pc); 2366 pc->c[0] = SPACE; 2367 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]); 2368 pc->c[1] = cmd; 2369 set_bit(PC_WAIT_FOR_DSC, &pc->flags); 2370 pc->callback = &idetape_pc_callback; 2371} 2372 2373static void idetape_wait_first_stage (ide_drive_t *drive) 2374{ 2375 idetape_tape_t *tape = drive->driver_data; 2376 unsigned long flags; 2377 2378 if (tape->first_stage == NULL) 2379 return; 2380 spin_lock_irqsave(&tape->spinlock, flags); 2381 if (tape->active_stage == tape->first_stage) 2382 idetape_wait_for_request(drive, tape->active_data_request); 2383 spin_unlock_irqrestore(&tape->spinlock, flags); 2384} 2385 2386/* 2387 * idetape_add_chrdev_write_request tries to add a character device 2388 * originated write request to our pipeline. In case we don't succeed, 2389 * we revert to non-pipelined operation mode for this request. 2390 * 2391 * 1. Try to allocate a new pipeline stage. 2392 * 2. If we can't, wait for more and more requests to be serviced 2393 * and try again each time. 2394 * 3. If we still can't allocate a stage, fallback to 2395 * non-pipelined operation mode for this request. 2396 */ 2397static int idetape_add_chrdev_write_request (ide_drive_t *drive, int blocks) 2398{ 2399 idetape_tape_t *tape = drive->driver_data; 2400 idetape_stage_t *new_stage; 2401 unsigned long flags; 2402 struct request *rq; 2403 2404 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 2405 2406 /* 2407 * Attempt to allocate a new stage. 2408 * Pay special attention to possible race conditions. 2409 */ 2410 while ((new_stage = idetape_kmalloc_stage(tape)) == NULL) { 2411 spin_lock_irqsave(&tape->spinlock, flags); 2412 if (idetape_pipeline_active(tape)) { 2413 idetape_wait_for_request(drive, tape->active_data_request); 2414 spin_unlock_irqrestore(&tape->spinlock, flags); 2415 } else { 2416 spin_unlock_irqrestore(&tape->spinlock, flags); 2417 idetape_insert_pipeline_into_queue(drive); 2418 if (idetape_pipeline_active(tape)) 2419 continue; 2420 /* 2421 * Linux is short on memory. Fallback to 2422 * non-pipelined operation mode for this request. 2423 */ 2424 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh); 2425 } 2426 } 2427 rq = &new_stage->rq; 2428 idetape_init_rq(rq, REQ_IDETAPE_WRITE); 2429 /* Doesn't actually matter - We always assume sequential access */ 2430 rq->sector = tape->first_frame_position; 2431 rq->nr_sectors = rq->current_nr_sectors = blocks; 2432 2433 idetape_switch_buffers(tape, new_stage); 2434 idetape_add_stage_tail(drive, new_stage); 2435 tape->pipeline_head++; 2436 calculate_speeds(drive); 2437 2438 /* 2439 * Estimate whether the tape has stopped writing by checking 2440 * if our write pipeline is currently empty. If we are not 2441 * writing anymore, wait for the pipeline to be full enough 2442 * (90%) before starting to service requests, so that we will 2443 * be able to keep up with the higher speeds of the tape. 2444 */ 2445 if (!idetape_pipeline_active(tape)) { 2446 if (tape->nr_stages >= tape->max_stages * 9 / 10 || 2447 tape->nr_stages >= tape->max_stages - tape->uncontrolled_pipeline_head_speed * 3 * 1024 / tape->tape_block_size) { 2448 tape->measure_insert_time = 1; 2449 tape->insert_time = jiffies; 2450 tape->insert_size = 0; 2451 tape->insert_speed = 0; 2452 idetape_insert_pipeline_into_queue(drive); 2453 } 2454 } 2455 if (test_and_clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags)) 2456 /* Return a deferred error */ 2457 return -EIO; 2458 return blocks; 2459} 2460 2461/* 2462 * idetape_wait_for_pipeline will wait until all pending pipeline 2463 * requests are serviced. Typically called on device close. 2464 */ 2465static void idetape_wait_for_pipeline (ide_drive_t *drive) 2466{ 2467 idetape_tape_t *tape = drive->driver_data; 2468 unsigned long flags; 2469 2470 while (tape->next_stage || idetape_pipeline_active(tape)) { 2471 idetape_insert_pipeline_into_queue(drive); 2472 spin_lock_irqsave(&tape->spinlock, flags); 2473 if (idetape_pipeline_active(tape)) 2474 idetape_wait_for_request(drive, tape->active_data_request); 2475 spin_unlock_irqrestore(&tape->spinlock, flags); 2476 } 2477} 2478 2479static void idetape_empty_write_pipeline (ide_drive_t *drive) 2480{ 2481 idetape_tape_t *tape = drive->driver_data; 2482 int blocks, min; 2483 struct idetape_bh *bh; 2484 2485 if (tape->chrdev_direction != idetape_direction_write) { 2486 printk(KERN_ERR "ide-tape: bug: Trying to empty write pipeline, but we are not writing.\n"); 2487 return; 2488 } 2489 if (tape->merge_stage_size > tape->stage_size) { 2490 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n"); 2491 tape->merge_stage_size = tape->stage_size; 2492 } 2493 if (tape->merge_stage_size) { 2494 blocks = tape->merge_stage_size / tape->tape_block_size; 2495 if (tape->merge_stage_size % tape->tape_block_size) { 2496 unsigned int i; 2497 2498 blocks++; 2499 i = tape->tape_block_size - tape->merge_stage_size % tape->tape_block_size; 2500 bh = tape->bh->b_reqnext; 2501 while (bh) { 2502 atomic_set(&bh->b_count, 0); 2503 bh = bh->b_reqnext; 2504 } 2505 bh = tape->bh; 2506 while (i) { 2507 if (bh == NULL) { 2508 2509 printk(KERN_INFO "ide-tape: bug, bh NULL\n"); 2510 break; 2511 } 2512 min = min(i, (unsigned int)(bh->b_size - atomic_read(&bh->b_count))); 2513 memset(bh->b_data + atomic_read(&bh->b_count), 0, min); 2514 atomic_add(min, &bh->b_count); 2515 i -= min; 2516 bh = bh->b_reqnext; 2517 } 2518 } 2519 (void) idetape_add_chrdev_write_request(drive, blocks); 2520 tape->merge_stage_size = 0; 2521 } 2522 idetape_wait_for_pipeline(drive); 2523 if (tape->merge_stage != NULL) { 2524 __idetape_kfree_stage(tape->merge_stage); 2525 tape->merge_stage = NULL; 2526 } 2527 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 2528 tape->chrdev_direction = idetape_direction_none; 2529 2530 /* 2531 * On the next backup, perform the feedback loop again. 2532 * (I don't want to keep sense information between backups, 2533 * as some systems are constantly on, and the system load 2534 * can be totally different on the next backup). 2535 */ 2536 tape->max_stages = tape->min_pipeline; 2537 if (tape->first_stage != NULL || 2538 tape->next_stage != NULL || 2539 tape->last_stage != NULL || 2540 tape->nr_stages != 0) { 2541 printk(KERN_ERR "ide-tape: ide-tape pipeline bug, " 2542 "first_stage %p, next_stage %p, " 2543 "last_stage %p, nr_stages %d\n", 2544 tape->first_stage, tape->next_stage, 2545 tape->last_stage, tape->nr_stages); 2546 } 2547} 2548 2549static void idetape_restart_speed_control (ide_drive_t *drive) 2550{ 2551 idetape_tape_t *tape = drive->driver_data; 2552 2553 tape->restart_speed_control_req = 0; 2554 tape->pipeline_head = 0; 2555 tape->controlled_last_pipeline_head = tape->uncontrolled_last_pipeline_head = 0; 2556 tape->controlled_previous_pipeline_head = tape->uncontrolled_previous_pipeline_head = 0; 2557 tape->pipeline_head_speed = tape->controlled_pipeline_head_speed = 5000; 2558 tape->uncontrolled_pipeline_head_speed = 0; 2559 tape->controlled_pipeline_head_time = tape->uncontrolled_pipeline_head_time = jiffies; 2560 tape->controlled_previous_head_time = tape->uncontrolled_previous_head_time = jiffies; 2561} 2562 2563static int idetape_initiate_read (ide_drive_t *drive, int max_stages) 2564{ 2565 idetape_tape_t *tape = drive->driver_data; 2566 idetape_stage_t *new_stage; 2567 struct request rq; 2568 int bytes_read; 2569 u16 blocks = *(u16 *)&tape->caps[12]; 2570 2571 /* Initialize read operation */ 2572 if (tape->chrdev_direction != idetape_direction_read) { 2573 if (tape->chrdev_direction == idetape_direction_write) { 2574 idetape_empty_write_pipeline(drive); 2575 idetape_flush_tape_buffers(drive); 2576 } 2577 if (tape->merge_stage || tape->merge_stage_size) { 2578 printk (KERN_ERR "ide-tape: merge_stage_size should be 0 now\n"); 2579 tape->merge_stage_size = 0; 2580 } 2581 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL) 2582 return -ENOMEM; 2583 tape->chrdev_direction = idetape_direction_read; 2584 2585 /* 2586 * Issue a read 0 command to ensure that DSC handshake 2587 * is switched from completion mode to buffer available 2588 * mode. 2589 * No point in issuing this if DSC overlap isn't supported, 2590 * some drives (Seagate STT3401A) will return an error. 2591 */ 2592 if (drive->dsc_overlap) { 2593 bytes_read = idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, 0, tape->merge_stage->bh); 2594 if (bytes_read < 0) { 2595 __idetape_kfree_stage(tape->merge_stage); 2596 tape->merge_stage = NULL; 2597 tape->chrdev_direction = idetape_direction_none; 2598 return bytes_read; 2599 } 2600 } 2601 } 2602 if (tape->restart_speed_control_req) 2603 idetape_restart_speed_control(drive); 2604 idetape_init_rq(&rq, REQ_IDETAPE_READ); 2605 rq.sector = tape->first_frame_position; 2606 rq.nr_sectors = rq.current_nr_sectors = blocks; 2607 if (!test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags) && 2608 tape->nr_stages < max_stages) { 2609 new_stage = idetape_kmalloc_stage(tape); 2610 while (new_stage != NULL) { 2611 new_stage->rq = rq; 2612 idetape_add_stage_tail(drive, new_stage); 2613 if (tape->nr_stages >= max_stages) 2614 break; 2615 new_stage = idetape_kmalloc_stage(tape); 2616 } 2617 } 2618 if (!idetape_pipeline_active(tape)) { 2619 if (tape->nr_pending_stages >= 3 * max_stages / 4) { 2620 tape->measure_insert_time = 1; 2621 tape->insert_time = jiffies; 2622 tape->insert_size = 0; 2623 tape->insert_speed = 0; 2624 idetape_insert_pipeline_into_queue(drive); 2625 } 2626 } 2627 return 0; 2628} 2629 2630/* 2631 * idetape_add_chrdev_read_request is called from idetape_chrdev_read 2632 * to service a character device read request and add read-ahead 2633 * requests to our pipeline. 2634 */ 2635static int idetape_add_chrdev_read_request (ide_drive_t *drive,int blocks) 2636{ 2637 idetape_tape_t *tape = drive->driver_data; 2638 unsigned long flags; 2639 struct request *rq_ptr; 2640 int bytes_read; 2641 2642 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks); 2643 2644 /* 2645 * If we are at a filemark, return a read length of 0 2646 */ 2647 if (test_bit(IDETAPE_FILEMARK, &tape->flags)) 2648 return 0; 2649 2650 /* 2651 * Wait for the next block to be available at the head 2652 * of the pipeline 2653 */ 2654 idetape_initiate_read(drive, tape->max_stages); 2655 if (tape->first_stage == NULL) { 2656 if (test_bit(IDETAPE_PIPELINE_ERROR, &tape->flags)) 2657 return 0; 2658 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks, tape->merge_stage->bh); 2659 } 2660 idetape_wait_first_stage(drive); 2661 rq_ptr = &tape->first_stage->rq; 2662 bytes_read = tape->tape_block_size * (rq_ptr->nr_sectors - rq_ptr->current_nr_sectors); 2663 rq_ptr->nr_sectors = rq_ptr->current_nr_sectors = 0; 2664 2665 2666 if (rq_ptr->errors == IDETAPE_ERROR_EOD) 2667 return 0; 2668 else { 2669 idetape_switch_buffers(tape, tape->first_stage); 2670 if (rq_ptr->errors == IDETAPE_ERROR_FILEMARK) 2671 set_bit(IDETAPE_FILEMARK, &tape->flags); 2672 spin_lock_irqsave(&tape->spinlock, flags); 2673 idetape_remove_stage_head(drive); 2674 spin_unlock_irqrestore(&tape->spinlock, flags); 2675 tape->pipeline_head++; 2676 calculate_speeds(drive); 2677 } 2678 if (bytes_read > blocks * tape->tape_block_size) { 2679 printk(KERN_ERR "ide-tape: bug: trying to return more bytes than requested\n"); 2680 bytes_read = blocks * tape->tape_block_size; 2681 } 2682 return (bytes_read); 2683} 2684 2685static void idetape_pad_zeros (ide_drive_t *drive, int bcount) 2686{ 2687 idetape_tape_t *tape = drive->driver_data; 2688 struct idetape_bh *bh; 2689 int blocks; 2690 2691 while (bcount) { 2692 unsigned int count; 2693 2694 bh = tape->merge_stage->bh; 2695 count = min(tape->stage_size, bcount); 2696 bcount -= count; 2697 blocks = count / tape->tape_block_size; 2698 while (count) { 2699 atomic_set(&bh->b_count, min(count, (unsigned int)bh->b_size)); 2700 memset(bh->b_data, 0, atomic_read(&bh->b_count)); 2701 count -= atomic_read(&bh->b_count); 2702 bh = bh->b_reqnext; 2703 } 2704 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks, tape->merge_stage->bh); 2705 } 2706} 2707 2708static int idetape_pipeline_size (ide_drive_t *drive) 2709{ 2710 idetape_tape_t *tape = drive->driver_data; 2711 idetape_stage_t *stage; 2712 struct request *rq; 2713 int size = 0; 2714 2715 idetape_wait_for_pipeline(drive); 2716 stage = tape->first_stage; 2717 while (stage != NULL) { 2718 rq = &stage->rq; 2719 size += tape->tape_block_size * (rq->nr_sectors-rq->current_nr_sectors); 2720 if (rq->errors == IDETAPE_ERROR_FILEMARK) 2721 size += tape->tape_block_size; 2722 stage = stage->next; 2723 } 2724 size += tape->merge_stage_size; 2725 return size; 2726} 2727 2728/* 2729 * Rewinds the tape to the Beginning Of the current Partition (BOP). 2730 * 2731 * We currently support only one partition. 2732 */ 2733static int idetape_rewind_tape (ide_drive_t *drive) 2734{ 2735 int retval; 2736 idetape_pc_t pc; 2737 idetape_tape_t *tape; 2738 tape = drive->driver_data; 2739 2740 debug_log(DBG_SENSE, "Enter %s\n", __func__); 2741 2742 idetape_create_rewind_cmd(drive, &pc); 2743 retval = idetape_queue_pc_tail(drive, &pc); 2744 if (retval) 2745 return retval; 2746 2747 idetape_create_read_position_cmd(&pc); 2748 retval = idetape_queue_pc_tail(drive, &pc); 2749 if (retval) 2750 return retval; 2751 return 0; 2752} 2753 2754/* 2755 * Our special ide-tape ioctl's. 2756 * 2757 * Currently there aren't any ioctl's. 2758 * mtio.h compatible commands should be issued to the character device 2759 * interface. 2760 */ 2761static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd, unsigned long arg) 2762{ 2763 idetape_tape_t *tape = drive->driver_data; 2764 void __user *argp = (void __user *)arg; 2765 2766 struct idetape_config { 2767 int dsc_rw_frequency; 2768 int dsc_media_access_frequency; 2769 int nr_stages; 2770 } config; 2771 2772 debug_log(DBG_PROCS, "Enter %s\n", __func__); 2773 2774 switch (cmd) { 2775 case 0x0340: 2776 if (copy_from_user(&config, argp, sizeof(config))) 2777 return -EFAULT; 2778 tape->best_dsc_rw_frequency = config.dsc_rw_frequency; 2779 tape->max_stages = config.nr_stages; 2780 break; 2781 case 0x0350: 2782 config.dsc_rw_frequency = (int) tape->best_dsc_rw_frequency; 2783 config.nr_stages = tape->max_stages; 2784 if (copy_to_user(argp, &config, sizeof(config))) 2785 return -EFAULT; 2786 break; 2787 default: 2788 return -EIO; 2789 } 2790 return 0; 2791} 2792 2793/* 2794 * idetape_space_over_filemarks is now a bit more complicated than just 2795 * passing the command to the tape since we may have crossed some 2796 * filemarks during our pipelined read-ahead mode. 2797 * 2798 * As a minor side effect, the pipeline enables us to support MTFSFM when 2799 * the filemark is in our internal pipeline even if the tape doesn't 2800 * support spacing over filemarks in the reverse direction. 2801 */ 2802static int idetape_space_over_filemarks (ide_drive_t *drive,short mt_op,int mt_count) 2803{ 2804 idetape_tape_t *tape = drive->driver_data; 2805 idetape_pc_t pc; 2806 unsigned long flags; 2807 int retval,count=0; 2808 int sprev = !!(tape->caps[4] & 0x20); 2809 2810 if (mt_count == 0) 2811 return 0; 2812 if (MTBSF == mt_op || MTBSFM == mt_op) { 2813 if (!sprev) 2814 return -EIO; 2815 mt_count = - mt_count; 2816 } 2817 2818 if (tape->chrdev_direction == idetape_direction_read) { 2819 /* 2820 * We have a read-ahead buffer. Scan it for crossed 2821 * filemarks. 2822 */ 2823 tape->merge_stage_size = 0; 2824 if (test_and_clear_bit(IDETAPE_FILEMARK, &tape->flags)) 2825 ++count; 2826 while (tape->first_stage != NULL) { 2827 if (count == mt_count) { 2828 if (mt_op == MTFSFM) 2829 set_bit(IDETAPE_FILEMARK, &tape->flags); 2830 return 0; 2831 } 2832 spin_lock_irqsave(&tape->spinlock, flags); 2833 if (tape->first_stage == tape->active_stage) { 2834 /* 2835 * We have reached the active stage in the read pipeline. 2836 * There is no point in allowing the drive to continue 2837 * reading any farther, so we stop the pipeline. 2838 * 2839 * This section should be moved to a separate subroutine, 2840 * because a similar function is performed in 2841 * __idetape_discard_read_pipeline(), for example. 2842 */ 2843 tape->next_stage = NULL; 2844 spin_unlock_irqrestore(&tape->spinlock, flags); 2845 idetape_wait_first_stage(drive); 2846 tape->next_stage = tape->first_stage->next; 2847 } else 2848 spin_unlock_irqrestore(&tape->spinlock, flags); 2849 if (tape->first_stage->rq.errors == IDETAPE_ERROR_FILEMARK) 2850 ++count; 2851 idetape_remove_stage_head(drive); 2852 } 2853 idetape_discard_read_pipeline(drive, 0); 2854 } 2855 2856 /* 2857 * The filemark was not found in our internal pipeline. 2858 * Now we can issue the space command. 2859 */ 2860 switch (mt_op) { 2861 case MTFSF: 2862 case MTBSF: 2863 idetape_create_space_cmd(&pc,mt_count-count,IDETAPE_SPACE_OVER_FILEMARK); 2864 return (idetape_queue_pc_tail(drive, &pc)); 2865 case MTFSFM: 2866 case MTBSFM: 2867 if (!sprev) 2868 return (-EIO); 2869 retval = idetape_space_over_filemarks(drive, MTFSF, mt_count-count); 2870 if (retval) return (retval); 2871 count = (MTBSFM == mt_op ? 1 : -1); 2872 return (idetape_space_over_filemarks(drive, MTFSF, count)); 2873 default: 2874 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",mt_op); 2875 return (-EIO); 2876 } 2877} 2878 2879 2880/* 2881 * Our character device read / write functions. 2882 * 2883 * The tape is optimized to maximize throughput when it is transferring 2884 * an integral number of the "continuous transfer limit", which is 2885 * a parameter of the specific tape (26 KB on my particular tape). 2886 * (32 kB for Onstream) 2887 * 2888 * As of version 1.3 of the driver, the character device provides an 2889 * abstract continuous view of the media - any mix of block sizes (even 1 2890 * byte) on the same backup/restore procedure is supported. The driver 2891 * will internally convert the requests to the recommended transfer unit, 2892 * so that an unmatch between the user's block size to the recommended 2893 * size will only result in a (slightly) increased driver overhead, but 2894 * will no longer hit performance. 2895 * This is not applicable to Onstream. 2896 */ 2897static ssize_t idetape_chrdev_read (struct file *file, char __user *buf, 2898 size_t count, loff_t *ppos) 2899{ 2900 struct ide_tape_obj *tape = ide_tape_f(file); 2901 ide_drive_t *drive = tape->drive; 2902 ssize_t bytes_read,temp, actually_read = 0, rc; 2903 ssize_t ret = 0; 2904 u16 ctl = *(u16 *)&tape->caps[12]; 2905 2906 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 2907 2908 if (tape->chrdev_direction != idetape_direction_read) { 2909 if (test_bit(IDETAPE_DETECT_BS, &tape->flags)) 2910 if (count > tape->tape_block_size && 2911 (count % tape->tape_block_size) == 0) 2912 tape->user_bs_factor = count / tape->tape_block_size; 2913 } 2914 if ((rc = idetape_initiate_read(drive, tape->max_stages)) < 0) 2915 return rc; 2916 if (count == 0) 2917 return (0); 2918 if (tape->merge_stage_size) { 2919 actually_read = min((unsigned int)(tape->merge_stage_size), (unsigned int)count); 2920 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, actually_read)) 2921 ret = -EFAULT; 2922 buf += actually_read; 2923 tape->merge_stage_size -= actually_read; 2924 count -= actually_read; 2925 } 2926 while (count >= tape->stage_size) { 2927 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2928 if (bytes_read <= 0) 2929 goto finish; 2930 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, bytes_read)) 2931 ret = -EFAULT; 2932 buf += bytes_read; 2933 count -= bytes_read; 2934 actually_read += bytes_read; 2935 } 2936 if (count) { 2937 bytes_read = idetape_add_chrdev_read_request(drive, ctl); 2938 if (bytes_read <= 0) 2939 goto finish; 2940 temp = min((unsigned long)count, (unsigned long)bytes_read); 2941 if (idetape_copy_stage_to_user(tape, buf, tape->merge_stage, temp)) 2942 ret = -EFAULT; 2943 actually_read += temp; 2944 tape->merge_stage_size = bytes_read-temp; 2945 } 2946finish: 2947 if (!actually_read && test_bit(IDETAPE_FILEMARK, &tape->flags)) { 2948 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name); 2949 2950 idetape_space_over_filemarks(drive, MTFSF, 1); 2951 return 0; 2952 } 2953 2954 return (ret) ? ret : actually_read; 2955} 2956 2957static ssize_t idetape_chrdev_write (struct file *file, const char __user *buf, 2958 size_t count, loff_t *ppos) 2959{ 2960 struct ide_tape_obj *tape = ide_tape_f(file); 2961 ide_drive_t *drive = tape->drive; 2962 ssize_t actually_written = 0; 2963 ssize_t ret = 0; 2964 u16 ctl = *(u16 *)&tape->caps[12]; 2965 2966 /* The drive is write protected. */ 2967 if (tape->write_prot) 2968 return -EACCES; 2969 2970 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count); 2971 2972 /* Initialize write operation */ 2973 if (tape->chrdev_direction != idetape_direction_write) { 2974 if (tape->chrdev_direction == idetape_direction_read) 2975 idetape_discard_read_pipeline(drive, 1); 2976 if (tape->merge_stage || tape->merge_stage_size) { 2977 printk(KERN_ERR "ide-tape: merge_stage_size " 2978 "should be 0 now\n"); 2979 tape->merge_stage_size = 0; 2980 } 2981 if ((tape->merge_stage = __idetape_kmalloc_stage(tape, 0, 0)) == NULL) 2982 return -ENOMEM; 2983 tape->chrdev_direction = idetape_direction_write; 2984 idetape_init_merge_stage(tape); 2985 2986 /* 2987 * Issue a write 0 command to ensure that DSC handshake 2988 * is switched from completion mode to buffer available 2989 * mode. 2990 * No point in issuing this if DSC overlap isn't supported, 2991 * some drives (Seagate STT3401A) will return an error. 2992 */ 2993 if (drive->dsc_overlap) { 2994 ssize_t retval = idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, 0, tape->merge_stage->bh); 2995 if (retval < 0) { 2996 __idetape_kfree_stage(tape->merge_stage); 2997 tape->merge_stage = NULL; 2998 tape->chrdev_direction = idetape_direction_none; 2999 return retval; 3000 } 3001 } 3002 } 3003 if (count == 0) 3004 return (0); 3005 if (tape->restart_speed_control_req) 3006 idetape_restart_speed_control(drive); 3007 if (tape->merge_stage_size) { 3008 if (tape->merge_stage_size >= tape->stage_size) { 3009 printk(KERN_ERR "ide-tape: bug: merge buffer too big\n"); 3010 tape->merge_stage_size = 0; 3011 } 3012 actually_written = min((unsigned int)(tape->stage_size - tape->merge_stage_size), (unsigned int)count); 3013 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, actually_written)) 3014 ret = -EFAULT; 3015 buf += actually_written; 3016 tape->merge_stage_size += actually_written; 3017 count -= actually_written; 3018 3019 if (tape->merge_stage_size == tape->stage_size) { 3020 ssize_t retval; 3021 tape->merge_stage_size = 0; 3022 retval = idetape_add_chrdev_write_request(drive, ctl); 3023 if (retval <= 0) 3024 return (retval); 3025 } 3026 } 3027 while (count >= tape->stage_size) { 3028 ssize_t retval; 3029 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, tape->stage_size)) 3030 ret = -EFAULT; 3031 buf += tape->stage_size; 3032 count -= tape->stage_size; 3033 retval = idetape_add_chrdev_write_request(drive, ctl); 3034 actually_written += tape->stage_size; 3035 if (retval <= 0) 3036 return (retval); 3037 } 3038 if (count) { 3039 actually_written += count; 3040 if (idetape_copy_stage_from_user(tape, tape->merge_stage, buf, count)) 3041 ret = -EFAULT; 3042 tape->merge_stage_size += count; 3043 } 3044 return (ret) ? ret : actually_written; 3045} 3046 3047static int idetape_write_filemark (ide_drive_t *drive) 3048{ 3049 idetape_pc_t pc; 3050 3051 /* Write a filemark */ 3052 idetape_create_write_filemark_cmd(drive, &pc, 1); 3053 if (idetape_queue_pc_tail(drive, &pc)) { 3054 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n"); 3055 return -EIO; 3056 } 3057 return 0; 3058} 3059 3060/* 3061 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is 3062 * requested. 3063 * 3064 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support 3065 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also 3066 * usually not supported (it is supported in the rare case in which we crossed 3067 * the filemark during our read-ahead pipelined operation mode). 3068 * 3069 * The following commands are currently not supported: 3070 * 3071 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS, 3072 * MT_ST_WRITE_THRESHOLD. 3073 */ 3074static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count) 3075{ 3076 idetape_tape_t *tape = drive->driver_data; 3077 idetape_pc_t pc; 3078 int i,retval; 3079 3080 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n", 3081 mt_op, mt_count); 3082 /* 3083 * Commands which need our pipelined read-ahead stages. 3084 */ 3085 switch (mt_op) { 3086 case MTFSF: 3087 case MTFSFM: 3088 case MTBSF: 3089 case MTBSFM: 3090 if (!mt_count) 3091 return (0); 3092 return (idetape_space_over_filemarks(drive,mt_op,mt_count)); 3093 default: 3094 break; 3095 } 3096 switch (mt_op) { 3097 case MTWEOF: 3098 if (tape->write_prot) 3099 return -EACCES; 3100 idetape_discard_read_pipeline(drive, 1); 3101 for (i = 0; i < mt_count; i++) { 3102 retval = idetape_write_filemark(drive); 3103 if (retval) 3104 return retval; 3105 } 3106 return (0); 3107 case MTREW: 3108 idetape_discard_read_pipeline(drive, 0); 3109 if (idetape_rewind_tape(drive)) 3110 return -EIO; 3111 return 0; 3112 case MTLOAD: 3113 idetape_discard_read_pipeline(drive, 0); 3114 idetape_create_load_unload_cmd(drive, &pc, IDETAPE_LU_LOAD_MASK); 3115 return (idetape_queue_pc_tail(drive, &pc)); 3116 case MTUNLOAD: 3117 case MTOFFL: 3118 /* 3119 * If door is locked, attempt to unlock before 3120 * attempting to eject. 3121 */ 3122 if (tape->door_locked) { 3123 if (idetape_create_prevent_cmd(drive, &pc, 0)) 3124 if (!idetape_queue_pc_tail(drive, &pc)) 3125 tape->door_locked = DOOR_UNLOCKED; 3126 } 3127 idetape_discard_read_pipeline(drive, 0); 3128 idetape_create_load_unload_cmd(drive, &pc,!IDETAPE_LU_LOAD_MASK); 3129 retval = idetape_queue_pc_tail(drive, &pc); 3130 if (!retval) 3131 clear_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags); 3132 return retval; 3133 case MTNOP: 3134 idetape_discard_read_pipeline(drive, 0); 3135 return (idetape_flush_tape_buffers(drive)); 3136 case MTRETEN: 3137 idetape_discard_read_pipeline(drive, 0); 3138 idetape_create_load_unload_cmd(drive, &pc,IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK); 3139 return (idetape_queue_pc_tail(drive, &pc)); 3140 case MTEOM: 3141 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD); 3142 return (idetape_queue_pc_tail(drive, &pc)); 3143 case MTERASE: 3144 (void) idetape_rewind_tape(drive); 3145 idetape_create_erase_cmd(&pc); 3146 return (idetape_queue_pc_tail(drive, &pc)); 3147 case MTSETBLK: 3148 if (mt_count) { 3149 if (mt_count < tape->tape_block_size || mt_count % tape->tape_block_size) 3150 return -EIO; 3151 tape->user_bs_factor = mt_count / tape->tape_block_size; 3152 clear_bit(IDETAPE_DETECT_BS, &tape->flags); 3153 } else 3154 set_bit(IDETAPE_DETECT_BS, &tape->flags); 3155 return 0; 3156 case MTSEEK: 3157 idetape_discard_read_pipeline(drive, 0); 3158 return idetape_position_tape(drive, mt_count * tape->user_bs_factor, tape->partition, 0); 3159 case MTSETPART: 3160 idetape_discard_read_pipeline(drive, 0); 3161 return (idetape_position_tape(drive, 0, mt_count, 0)); 3162 case MTFSR: 3163 case MTBSR: 3164 case MTLOCK: 3165 if (!idetape_create_prevent_cmd(drive, &pc, 1)) 3166 return 0; 3167 retval = idetape_queue_pc_tail(drive, &pc); 3168 if (retval) return retval; 3169 tape->door_locked = DOOR_EXPLICITLY_LOCKED; 3170 return 0; 3171 case MTUNLOCK: 3172 if (!idetape_create_prevent_cmd(drive, &pc, 0)) 3173 return 0; 3174 retval = idetape_queue_pc_tail(drive, &pc); 3175 if (retval) return retval; 3176 tape->door_locked = DOOR_UNLOCKED; 3177 return 0; 3178 default: 3179 printk(KERN_ERR "ide-tape: MTIO operation %d not " 3180 "supported\n", mt_op); 3181 return (-EIO); 3182 } 3183} 3184 3185/* 3186 * Our character device ioctls. General mtio.h magnetic io commands are 3187 * supported here, and not in the corresponding block interface. Our own 3188 * ide-tape ioctls are supported on both interfaces. 3189 */ 3190static int idetape_chrdev_ioctl(struct inode *inode, struct file *file, 3191 unsigned int cmd, unsigned long arg) 3192{ 3193 struct ide_tape_obj *tape = ide_tape_f(file); 3194 ide_drive_t *drive = tape->drive; 3195 struct mtop mtop; 3196 struct mtget mtget; 3197 struct mtpos mtpos; 3198 int block_offset = 0, position = tape->first_frame_position; 3199 void __user *argp = (void __user *)arg; 3200 3201 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd); 3202 3203 tape->restart_speed_control_req = 1; 3204 if (tape->chrdev_direction == idetape_direction_write) { 3205 idetape_empty_write_pipeline(drive); 3206 idetape_flush_tape_buffers(drive); 3207 } 3208 if (cmd == MTIOCGET || cmd == MTIOCPOS) { 3209 block_offset = idetape_pipeline_size(drive) / (tape->tape_block_size * tape->user_bs_factor); 3210 if ((position = idetape_read_position(drive)) < 0) 3211 return -EIO; 3212 } 3213 switch (cmd) { 3214 case MTIOCTOP: 3215 if (copy_from_user(&mtop, argp, sizeof (struct mtop))) 3216 return -EFAULT; 3217 return (idetape_mtioctop(drive,mtop.mt_op,mtop.mt_count)); 3218 case MTIOCGET: 3219 memset(&mtget, 0, sizeof (struct mtget)); 3220 mtget.mt_type = MT_ISSCSI2; 3221 mtget.mt_blkno = position / tape->user_bs_factor - block_offset; 3222 mtget.mt_dsreg = ((tape->tape_block_size * tape->user_bs_factor) << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK; 3223 if (tape->drv_write_prot) { 3224 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff); 3225 } 3226 if (copy_to_user(argp, &mtget, sizeof(struct mtget))) 3227 return -EFAULT; 3228 return 0; 3229 case MTIOCPOS: 3230 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset; 3231 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos))) 3232 return -EFAULT; 3233 return 0; 3234 default: 3235 if (tape->chrdev_direction == idetape_direction_read) 3236 idetape_discard_read_pipeline(drive, 1); 3237 return idetape_blkdev_ioctl(drive, cmd, arg); 3238 } 3239} 3240 3241/* 3242 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape 3243 * block size with the reported value. 3244 */ 3245static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive) 3246{ 3247 idetape_tape_t *tape = drive->driver_data; 3248 idetape_pc_t pc; 3249 3250 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR); 3251 if (idetape_queue_pc_tail(drive, &pc)) { 3252 printk(KERN_ERR "ide-tape: Can't get block descriptor\n"); 3253 if (tape->tape_block_size == 0) { 3254 printk(KERN_WARNING "ide-tape: Cannot deal with zero " 3255 "block size, assuming 32k\n"); 3256 tape->tape_block_size = 32768; 3257 } 3258 return; 3259 } 3260 tape->tape_block_size = (pc.buffer[4 + 5] << 16) + 3261 (pc.buffer[4 + 6] << 8) + 3262 pc.buffer[4 + 7]; 3263 tape->drv_write_prot = (pc.buffer[2] & 0x80) >> 7; 3264} 3265 3266/* 3267 * Our character device open function. 3268 */ 3269static int idetape_chrdev_open (struct inode *inode, struct file *filp) 3270{ 3271 unsigned int minor = iminor(inode), i = minor & ~0xc0; 3272 ide_drive_t *drive; 3273 idetape_tape_t *tape; 3274 idetape_pc_t pc; 3275 int retval; 3276 3277 if (i >= MAX_HWIFS * MAX_DRIVES) 3278 return -ENXIO; 3279 3280 tape = ide_tape_chrdev_get(i); 3281 if (!tape) 3282 return -ENXIO; 3283 3284 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 3285 3286 /* 3287 * We really want to do nonseekable_open(inode, filp); here, but some 3288 * versions of tar incorrectly call lseek on tapes and bail out if that 3289 * fails. So we disallow pread() and pwrite(), but permit lseeks. 3290 */ 3291 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE); 3292 3293 drive = tape->drive; 3294 3295 filp->private_data = tape; 3296 3297 if (test_and_set_bit(IDETAPE_BUSY, &tape->flags)) { 3298 retval = -EBUSY; 3299 goto out_put_tape; 3300 } 3301 3302 retval = idetape_wait_ready(drive, 60 * HZ); 3303 if (retval) { 3304 clear_bit(IDETAPE_BUSY, &tape->flags); 3305 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name); 3306 goto out_put_tape; 3307 } 3308 3309 idetape_read_position(drive); 3310 if (!test_bit(IDETAPE_ADDRESS_VALID, &tape->flags)) 3311 (void)idetape_rewind_tape(drive); 3312 3313 if (tape->chrdev_direction != idetape_direction_read) 3314 clear_bit(IDETAPE_PIPELINE_ERROR, &tape->flags); 3315 3316 /* Read block size and write protect status from drive. */ 3317 ide_tape_get_bsize_from_bdesc(drive); 3318 3319 /* Set write protect flag if device is opened as read-only. */ 3320 if ((filp->f_flags & O_ACCMODE) == O_RDONLY) 3321 tape->write_prot = 1; 3322 else 3323 tape->write_prot = tape->drv_write_prot; 3324 3325 /* Make sure drive isn't write protected if user wants to write. */ 3326 if (tape->write_prot) { 3327 if ((filp->f_flags & O_ACCMODE) == O_WRONLY || 3328 (filp->f_flags & O_ACCMODE) == O_RDWR) { 3329 clear_bit(IDETAPE_BUSY, &tape->flags); 3330 retval = -EROFS; 3331 goto out_put_tape; 3332 } 3333 } 3334 3335 /* 3336 * Lock the tape drive door so user can't eject. 3337 */ 3338 if (tape->chrdev_direction == idetape_direction_none) { 3339 if (idetape_create_prevent_cmd(drive, &pc, 1)) { 3340 if (!idetape_queue_pc_tail(drive, &pc)) { 3341 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED) 3342 tape->door_locked = DOOR_LOCKED; 3343 } 3344 } 3345 } 3346 idetape_restart_speed_control(drive); 3347 tape->restart_speed_control_req = 0; 3348 return 0; 3349 3350out_put_tape: 3351 ide_tape_put(tape); 3352 return retval; 3353} 3354 3355static void idetape_write_release (ide_drive_t *drive, unsigned int minor) 3356{ 3357 idetape_tape_t *tape = drive->driver_data; 3358 3359 idetape_empty_write_pipeline(drive); 3360 tape->merge_stage = __idetape_kmalloc_stage(tape, 1, 0); 3361 if (tape->merge_stage != NULL) { 3362 idetape_pad_zeros(drive, tape->tape_block_size * (tape->user_bs_factor - 1)); 3363 __idetape_kfree_stage(tape->merge_stage); 3364 tape->merge_stage = NULL; 3365 } 3366 idetape_write_filemark(drive); 3367 idetape_flush_tape_buffers(drive); 3368 idetape_flush_tape_buffers(drive); 3369} 3370 3371/* 3372 * Our character device release function. 3373 */ 3374static int idetape_chrdev_release (struct inode *inode, struct file *filp) 3375{ 3376 struct ide_tape_obj *tape = ide_tape_f(filp); 3377 ide_drive_t *drive = tape->drive; 3378 idetape_pc_t pc; 3379 unsigned int minor = iminor(inode); 3380 3381 lock_kernel(); 3382 tape = drive->driver_data; 3383 3384 debug_log(DBG_CHRDEV, "Enter %s\n", __func__); 3385 3386 if (tape->chrdev_direction == idetape_direction_write) 3387 idetape_write_release(drive, minor); 3388 if (tape->chrdev_direction == idetape_direction_read) { 3389 if (minor < 128) 3390 idetape_discard_read_pipeline(drive, 1); 3391 else 3392 idetape_wait_for_pipeline(drive); 3393 } 3394 if (tape->cache_stage != NULL) { 3395 __idetape_kfree_stage(tape->cache_stage); 3396 tape->cache_stage = NULL; 3397 } 3398 if (minor < 128 && test_bit(IDETAPE_MEDIUM_PRESENT, &tape->flags)) 3399 (void) idetape_rewind_tape(drive); 3400 if (tape->chrdev_direction == idetape_direction_none) { 3401 if (tape->door_locked == DOOR_LOCKED) { 3402 if (idetape_create_prevent_cmd(drive, &pc, 0)) { 3403 if (!idetape_queue_pc_tail(drive, &pc)) 3404 tape->door_locked = DOOR_UNLOCKED; 3405 } 3406 } 3407 } 3408 clear_bit(IDETAPE_BUSY, &tape->flags); 3409 ide_tape_put(tape); 3410 unlock_kernel(); 3411 return 0; 3412} 3413 3414/* 3415 * idetape_identify_device is called to check the contents of the 3416 * ATAPI IDENTIFY command results. We return: 3417 * 3418 * 1 If the tape can be supported by us, based on the information 3419 * we have so far. 3420 * 3421 * 0 If this tape driver is not currently supported by us. 3422 */ 3423static int idetape_identify_device (ide_drive_t *drive) 3424{ 3425 struct idetape_id_gcw gcw; 3426 struct hd_driveid *id = drive->id; 3427 3428 if (drive->id_read == 0) 3429 return 1; 3430 3431 *((unsigned short *) &gcw) = id->config; 3432 3433 /* Check that we can support this device */ 3434 3435 if (gcw.protocol != 2) 3436 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n", 3437 gcw.protocol); 3438 else if (gcw.device_type != 1) 3439 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set " 3440 "to tape\n", gcw.device_type); 3441 else if (!gcw.removable) 3442 printk(KERN_ERR "ide-tape: The removable flag is not set\n"); 3443 else if (gcw.packet_size != 0) { 3444 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12 " 3445 "bytes long\n", gcw.packet_size); 3446 } else 3447 return 1; 3448 return 0; 3449} 3450 3451static void idetape_get_inquiry_results(ide_drive_t *drive) 3452{ 3453 char *r; 3454 idetape_tape_t *tape = drive->driver_data; 3455 idetape_pc_t pc; 3456 3457 idetape_create_inquiry_cmd(&pc); 3458 if (idetape_queue_pc_tail(drive, &pc)) { 3459 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n", 3460 tape->name); 3461 return; 3462 } 3463 memcpy(tape->vendor_id, &pc.buffer[8], 8); 3464 memcpy(tape->product_id, &pc.buffer[16], 16); 3465 memcpy(tape->firmware_revision, &pc.buffer[32], 4); 3466 3467 ide_fixstring(tape->vendor_id, 10, 0); 3468 ide_fixstring(tape->product_id, 18, 0); 3469 ide_fixstring(tape->firmware_revision, 6, 0); 3470 r = tape->firmware_revision; 3471 if (*(r + 1) == '.') 3472 tape->firmware_revision_num = (*r - '0') * 100 + 3473 (*(r + 2) - '0') * 10 + *(r + 3) - '0'; 3474 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n", 3475 drive->name, tape->name, tape->vendor_id, 3476 tape->product_id, tape->firmware_revision); 3477} 3478 3479/* 3480 * Ask the tape about its various parameters. In particular, we will adjust our 3481 * data transfer buffer size to the recommended value as returned by the tape. 3482 */ 3483static void idetape_get_mode_sense_results (ide_drive_t *drive) 3484{ 3485 idetape_tape_t *tape = drive->driver_data; 3486 idetape_pc_t pc; 3487 u8 *caps; 3488 u8 speed, max_speed; 3489 3490 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE); 3491 if (idetape_queue_pc_tail(drive, &pc)) { 3492 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming" 3493 " some default values\n"); 3494 tape->tape_block_size = 512; 3495 put_unaligned(52, (u16 *)&tape->caps[12]); 3496 put_unaligned(540, (u16 *)&tape->caps[14]); 3497 put_unaligned(6*52, (u16 *)&tape->caps[16]); 3498 return; 3499 } 3500 caps = pc.buffer + 4 + pc.buffer[3]; 3501 3502 /* convert to host order and save for later use */ 3503 speed = be16_to_cpu(*(u16 *)&caps[14]); 3504 max_speed = be16_to_cpu(*(u16 *)&caps[8]); 3505 3506 put_unaligned(max_speed, (u16 *)&caps[8]); 3507 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]); 3508 put_unaligned(speed, (u16 *)&caps[14]); 3509 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]); 3510 3511 if (!speed) { 3512 printk(KERN_INFO "ide-tape: %s: invalid tape speed " 3513 "(assuming 650KB/sec)\n", drive->name); 3514 put_unaligned(650, (u16 *)&caps[14]); 3515 } 3516 if (!max_speed) { 3517 printk(KERN_INFO "ide-tape: %s: invalid max_speed " 3518 "(assuming 650KB/sec)\n", drive->name); 3519 put_unaligned(650, (u16 *)&caps[8]); 3520 } 3521 3522 memcpy(&tape->caps, caps, 20); 3523 if (caps[7] & 0x02) 3524 tape->tape_block_size = 512; 3525 else if (caps[7] & 0x04) 3526 tape->tape_block_size = 1024; 3527} 3528 3529#ifdef CONFIG_IDE_PROC_FS 3530static void idetape_add_settings (ide_drive_t *drive) 3531{ 3532 idetape_tape_t *tape = drive->driver_data; 3533 3534/* 3535 * drive setting name read/write data type min max mul_factor div_factor data pointer set function 3536 */ 3537 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff, 3538 1, 2, (u16 *)&tape->caps[16], NULL); 3539 ide_add_setting(drive, "pipeline_min", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->min_pipeline, NULL); 3540 ide_add_setting(drive, "pipeline", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_stages, NULL); 3541 ide_add_setting(drive, "pipeline_max", SETTING_RW, TYPE_INT, 1, 0xffff, tape->stage_size / 1024, 1, &tape->max_pipeline, NULL); 3542 ide_add_setting(drive, "pipeline_used", SETTING_READ, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_stages, NULL); 3543 ide_add_setting(drive, "pipeline_pending", SETTING_READ, TYPE_INT, 0, 0xffff, tape->stage_size / 1024, 1, &tape->nr_pending_stages, NULL); 3544 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff, 3545 1, 1, (u16 *)&tape->caps[14], NULL); 3546 ide_add_setting(drive, "stage", SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1024, &tape->stage_size, NULL); 3547 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); 3548 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1, 1, &drive->dsc_overlap, NULL); 3549 ide_add_setting(drive, "pipeline_head_speed_c",SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->controlled_pipeline_head_speed, NULL); 3550 ide_add_setting(drive, "pipeline_head_speed_u",SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->uncontrolled_pipeline_head_speed,NULL); 3551 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff, 1, 1, &tape->avg_speed, NULL); 3552 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1, 3553 1, &tape->debug_mask, NULL); 3554} 3555#else 3556static inline void idetape_add_settings(ide_drive_t *drive) { ; } 3557#endif 3558 3559/* 3560 * ide_setup is called to: 3561 * 3562 * 1. Initialize our various state variables. 3563 * 2. Ask the tape for its capabilities. 3564 * 3. Allocate a buffer which will be used for data 3565 * transfer. The buffer size is chosen based on 3566 * the recommendation which we received in step (2). 3567 * 3568 * Note that at this point ide.c already assigned us an irq, so that 3569 * we can queue requests here and wait for their completion. 3570 */ 3571static void idetape_setup (ide_drive_t *drive, idetape_tape_t *tape, int minor) 3572{ 3573 unsigned long t1, tmid, tn, t; 3574 int speed; 3575 struct idetape_id_gcw gcw; 3576 int stage_size; 3577 struct sysinfo si; 3578 u16 *ctl = (u16 *)&tape->caps[12]; 3579 3580 spin_lock_init(&tape->spinlock); 3581 drive->dsc_overlap = 1; 3582 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) { 3583 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n", 3584 tape->name); 3585 drive->dsc_overlap = 0; 3586 } 3587 /* Seagate Travan drives do not support DSC overlap. */ 3588 if (strstr(drive->id->model, "Seagate STT3401")) 3589 drive->dsc_overlap = 0; 3590 tape->minor = minor; 3591 tape->name[0] = 'h'; 3592 tape->name[1] = 't'; 3593 tape->name[2] = '0' + minor; 3594 tape->chrdev_direction = idetape_direction_none; 3595 tape->pc = tape->pc_stack; 3596 tape->max_insert_speed = 10000; 3597 tape->speed_control = 1; 3598 *((unsigned short *) &gcw) = drive->id->config; 3599 if (gcw.drq_type == 1) 3600 set_bit(IDETAPE_DRQ_INTERRUPT, &tape->flags); 3601 3602 tape->min_pipeline = tape->max_pipeline = tape->max_stages = 10; 3603 3604 idetape_get_inquiry_results(drive); 3605 idetape_get_mode_sense_results(drive); 3606 ide_tape_get_bsize_from_bdesc(drive); 3607 tape->user_bs_factor = 1; 3608 tape->stage_size = *ctl * tape->tape_block_size; 3609 while (tape->stage_size > 0xffff) { 3610 printk(KERN_NOTICE "ide-tape: decreasing stage size\n"); 3611 *ctl /= 2; 3612 tape->stage_size = *ctl * tape->tape_block_size; 3613 } 3614 stage_size = tape->stage_size; 3615 tape->pages_per_stage = stage_size / PAGE_SIZE; 3616 if (stage_size % PAGE_SIZE) { 3617 tape->pages_per_stage++; 3618 tape->excess_bh_size = PAGE_SIZE - stage_size % PAGE_SIZE; 3619 } 3620 3621 /* Select the "best" DSC read/write polling freq and pipeline size. */ 3622 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]); 3623 3624 tape->max_stages = speed * 1000 * 10 / tape->stage_size; 3625 3626 /* 3627 * Limit memory use for pipeline to 10% of physical memory 3628 */ 3629 si_meminfo(&si); 3630 if (tape->max_stages * tape->stage_size > si.totalram * si.mem_unit / 10) 3631 tape->max_stages = si.totalram * si.mem_unit / (10 * tape->stage_size); 3632 tape->max_stages = min(tape->max_stages, IDETAPE_MAX_PIPELINE_STAGES); 3633 tape->min_pipeline = min(tape->max_stages, IDETAPE_MIN_PIPELINE_STAGES); 3634 tape->max_pipeline = min(tape->max_stages * 2, IDETAPE_MAX_PIPELINE_STAGES); 3635 if (tape->max_stages == 0) 3636 tape->max_stages = tape->min_pipeline = tape->max_pipeline = 1; 3637 3638 t1 = (tape->stage_size * HZ) / (speed * 1000); 3639 tmid = (*(u16 *)&tape->caps[16] * 32 * HZ) / (speed * 125); 3640 tn = (IDETAPE_FIFO_THRESHOLD * tape->stage_size * HZ) / (speed * 1000); 3641 3642 if (tape->max_stages) 3643 t = tn; 3644 else 3645 t = t1; 3646 3647 /* 3648 * Ensure that the number we got makes sense; limit 3649 * it within IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX. 3650 */ 3651 tape->best_dsc_rw_frequency = max_t(unsigned long, min_t(unsigned long, t, IDETAPE_DSC_RW_MAX), IDETAPE_DSC_RW_MIN); 3652 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, " 3653 "%dkB pipeline, %lums tDSC%s\n", 3654 drive->name, tape->name, *(u16 *)&tape->caps[14], 3655 (*(u16 *)&tape->caps[16] * 512) / tape->stage_size, 3656 tape->stage_size / 1024, 3657 tape->max_stages * tape->stage_size / 1024, 3658 tape->best_dsc_rw_frequency * 1000 / HZ, 3659 drive->using_dma ? ", DMA":""); 3660 3661 idetape_add_settings(drive); 3662} 3663 3664static void ide_tape_remove(ide_drive_t *drive) 3665{ 3666 idetape_tape_t *tape = drive->driver_data; 3667 3668 ide_proc_unregister_driver(drive, tape->driver); 3669 3670 ide_unregister_region(tape->disk); 3671 3672 ide_tape_put(tape); 3673} 3674 3675static void ide_tape_release(struct kref *kref) 3676{ 3677 struct ide_tape_obj *tape = to_ide_tape(kref); 3678 ide_drive_t *drive = tape->drive; 3679 struct gendisk *g = tape->disk; 3680 3681 BUG_ON(tape->first_stage != NULL || tape->merge_stage_size); 3682 3683 drive->dsc_overlap = 0; 3684 drive->driver_data = NULL; 3685 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor)); 3686 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor + 128)); 3687 idetape_devs[tape->minor] = NULL; 3688 g->private_data = NULL; 3689 put_disk(g); 3690 kfree(tape); 3691} 3692 3693#ifdef CONFIG_IDE_PROC_FS 3694static int proc_idetape_read_name 3695 (char *page, char **start, off_t off, int count, int *eof, void *data) 3696{ 3697 ide_drive_t *drive = (ide_drive_t *) data; 3698 idetape_tape_t *tape = drive->driver_data; 3699 char *out = page; 3700 int len; 3701 3702 len = sprintf(out, "%s\n", tape->name); 3703 PROC_IDE_READ_RETURN(page, start, off, count, eof, len); 3704} 3705 3706static ide_proc_entry_t idetape_proc[] = { 3707 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL }, 3708 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL }, 3709 { NULL, 0, NULL, NULL } 3710}; 3711#endif 3712 3713static int ide_tape_probe(ide_drive_t *); 3714 3715static ide_driver_t idetape_driver = { 3716 .gen_driver = { 3717 .owner = THIS_MODULE, 3718 .name = "ide-tape", 3719 .bus = &ide_bus_type, 3720 }, 3721 .probe = ide_tape_probe, 3722 .remove = ide_tape_remove, 3723 .version = IDETAPE_VERSION, 3724 .media = ide_tape, 3725 .supports_dsc_overlap = 1, 3726 .do_request = idetape_do_request, 3727 .end_request = idetape_end_request, 3728 .error = __ide_error, 3729 .abort = __ide_abort, 3730#ifdef CONFIG_IDE_PROC_FS 3731 .proc = idetape_proc, 3732#endif 3733}; 3734 3735/* 3736 * Our character device supporting functions, passed to register_chrdev. 3737 */ 3738static const struct file_operations idetape_fops = { 3739 .owner = THIS_MODULE, 3740 .read = idetape_chrdev_read, 3741 .write = idetape_chrdev_write, 3742 .ioctl = idetape_chrdev_ioctl, 3743 .open = idetape_chrdev_open, 3744 .release = idetape_chrdev_release, 3745}; 3746 3747static int idetape_open(struct inode *inode, struct file *filp) 3748{ 3749 struct gendisk *disk = inode->i_bdev->bd_disk; 3750 struct ide_tape_obj *tape; 3751 3752 if (!(tape = ide_tape_get(disk))) 3753 return -ENXIO; 3754 3755 return 0; 3756} 3757 3758static int idetape_release(struct inode *inode, struct file *filp) 3759{ 3760 struct gendisk *disk = inode->i_bdev->bd_disk; 3761 struct ide_tape_obj *tape = ide_tape_g(disk); 3762 3763 ide_tape_put(tape); 3764 3765 return 0; 3766} 3767 3768static int idetape_ioctl(struct inode *inode, struct file *file, 3769 unsigned int cmd, unsigned long arg) 3770{ 3771 struct block_device *bdev = inode->i_bdev; 3772 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk); 3773 ide_drive_t *drive = tape->drive; 3774 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg); 3775 if (err == -EINVAL) 3776 err = idetape_blkdev_ioctl(drive, cmd, arg); 3777 return err; 3778} 3779 3780static struct block_device_operations idetape_block_ops = { 3781 .owner = THIS_MODULE, 3782 .open = idetape_open, 3783 .release = idetape_release, 3784 .ioctl = idetape_ioctl, 3785}; 3786 3787static int ide_tape_probe(ide_drive_t *drive) 3788{ 3789 idetape_tape_t *tape; 3790 struct gendisk *g; 3791 int minor; 3792 3793 if (!strstr("ide-tape", drive->driver_req)) 3794 goto failed; 3795 if (!drive->present) 3796 goto failed; 3797 if (drive->media != ide_tape) 3798 goto failed; 3799 if (!idetape_identify_device (drive)) { 3800 printk(KERN_ERR "ide-tape: %s: not supported by this version of ide-tape\n", drive->name); 3801 goto failed; 3802 } 3803 if (drive->scsi) { 3804 printk("ide-tape: passing drive %s to ide-scsi emulation.\n", drive->name); 3805 goto failed; 3806 } 3807 if (strstr(drive->id->model, "OnStream DI-")) { 3808 printk(KERN_WARNING "ide-tape: Use drive %s with ide-scsi emulation and osst.\n", drive->name); 3809 printk(KERN_WARNING "ide-tape: OnStream support will be removed soon from ide-tape!\n"); 3810 } 3811 tape = kzalloc(sizeof (idetape_tape_t), GFP_KERNEL); 3812 if (tape == NULL) { 3813 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape structure\n", drive->name); 3814 goto failed; 3815 } 3816 3817 g = alloc_disk(1 << PARTN_BITS); 3818 if (!g) 3819 goto out_free_tape; 3820 3821 ide_init_disk(g, drive); 3822 3823 ide_proc_register_driver(drive, &idetape_driver); 3824 3825 kref_init(&tape->kref); 3826 3827 tape->drive = drive; 3828 tape->driver = &idetape_driver; 3829 tape->disk = g; 3830 3831 g->private_data = &tape->driver; 3832 3833 drive->driver_data = tape; 3834 3835 mutex_lock(&idetape_ref_mutex); 3836 for (minor = 0; idetape_devs[minor]; minor++) 3837 ; 3838 idetape_devs[minor] = tape; 3839 mutex_unlock(&idetape_ref_mutex); 3840 3841 idetape_setup(drive, tape, minor); 3842 3843 device_create(idetape_sysfs_class, &drive->gendev, 3844 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name); 3845 device_create(idetape_sysfs_class, &drive->gendev, 3846 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name); 3847 3848 g->fops = &idetape_block_ops; 3849 ide_register_region(g); 3850 3851 return 0; 3852 3853out_free_tape: 3854 kfree(tape); 3855failed: 3856 return -ENODEV; 3857} 3858 3859MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver"); 3860MODULE_LICENSE("GPL"); 3861 3862static void __exit idetape_exit (void) 3863{ 3864 driver_unregister(&idetape_driver.gen_driver); 3865 class_destroy(idetape_sysfs_class); 3866 unregister_chrdev(IDETAPE_MAJOR, "ht"); 3867} 3868 3869static int __init idetape_init(void) 3870{ 3871 int error = 1; 3872 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape"); 3873 if (IS_ERR(idetape_sysfs_class)) { 3874 idetape_sysfs_class = NULL; 3875 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n"); 3876 error = -EBUSY; 3877 goto out; 3878 } 3879 3880 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) { 3881 printk(KERN_ERR "ide-tape: Failed to register character device interface\n"); 3882 error = -EBUSY; 3883 goto out_free_class; 3884 } 3885 3886 error = driver_register(&idetape_driver.gen_driver); 3887 if (error) 3888 goto out_free_driver; 3889 3890 return 0; 3891 3892out_free_driver: 3893 driver_unregister(&idetape_driver.gen_driver); 3894out_free_class: 3895 class_destroy(idetape_sysfs_class); 3896out: 3897 return error; 3898} 3899 3900MODULE_ALIAS("ide:*m-tape*"); 3901module_init(idetape_init); 3902module_exit(idetape_exit); 3903MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR); 3904