ide-io.c revision 18a056feccabdfa9764016a615121b194828bc72
1/* 2 * IDE I/O functions 3 * 4 * Basic PIO and command management functionality. 5 * 6 * This code was split off from ide.c. See ide.c for history and original 7 * copyrights. 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2, or (at your option) any 12 * later version. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * For the avoidance of doubt the "preferred form" of this code is one which 20 * is in an open non patent encumbered format. Where cryptographic key signing 21 * forms part of the process of creating an executable the information 22 * including keys needed to generate an equivalently functional executable 23 * are deemed to be part of the source code. 24 */ 25 26 27#include <linux/module.h> 28#include <linux/types.h> 29#include <linux/string.h> 30#include <linux/kernel.h> 31#include <linux/timer.h> 32#include <linux/mm.h> 33#include <linux/interrupt.h> 34#include <linux/major.h> 35#include <linux/errno.h> 36#include <linux/genhd.h> 37#include <linux/blkpg.h> 38#include <linux/slab.h> 39#include <linux/init.h> 40#include <linux/pci.h> 41#include <linux/delay.h> 42#include <linux/ide.h> 43#include <linux/completion.h> 44#include <linux/reboot.h> 45#include <linux/cdrom.h> 46#include <linux/seq_file.h> 47#include <linux/device.h> 48#include <linux/kmod.h> 49#include <linux/scatterlist.h> 50#include <linux/bitops.h> 51 52#include <asm/byteorder.h> 53#include <asm/irq.h> 54#include <asm/uaccess.h> 55#include <asm/io.h> 56 57static int __ide_end_request(ide_drive_t *drive, struct request *rq, 58 int uptodate, unsigned int nr_bytes, int dequeue) 59{ 60 int ret = 1; 61 62 /* 63 * if failfast is set on a request, override number of sectors and 64 * complete the whole request right now 65 */ 66 if (blk_noretry_request(rq) && end_io_error(uptodate)) 67 nr_bytes = rq->hard_nr_sectors << 9; 68 69 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors) 70 rq->errors = -EIO; 71 72 /* 73 * decide whether to reenable DMA -- 3 is a random magic for now, 74 * if we DMA timeout more than 3 times, just stay in PIO 75 */ 76 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) { 77 drive->state = 0; 78 ide_dma_on(drive); 79 } 80 81 if (!end_that_request_chunk(rq, uptodate, nr_bytes)) { 82 add_disk_randomness(rq->rq_disk); 83 if (dequeue) { 84 if (!list_empty(&rq->queuelist)) 85 blkdev_dequeue_request(rq); 86 HWGROUP(drive)->rq = NULL; 87 } 88 end_that_request_last(rq, uptodate); 89 ret = 0; 90 } 91 92 return ret; 93} 94 95/** 96 * ide_end_request - complete an IDE I/O 97 * @drive: IDE device for the I/O 98 * @uptodate: 99 * @nr_sectors: number of sectors completed 100 * 101 * This is our end_request wrapper function. We complete the I/O 102 * update random number input and dequeue the request, which if 103 * it was tagged may be out of order. 104 */ 105 106int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors) 107{ 108 unsigned int nr_bytes = nr_sectors << 9; 109 struct request *rq; 110 unsigned long flags; 111 int ret = 1; 112 113 /* 114 * room for locking improvements here, the calls below don't 115 * need the queue lock held at all 116 */ 117 spin_lock_irqsave(&ide_lock, flags); 118 rq = HWGROUP(drive)->rq; 119 120 if (!nr_bytes) { 121 if (blk_pc_request(rq)) 122 nr_bytes = rq->data_len; 123 else 124 nr_bytes = rq->hard_cur_sectors << 9; 125 } 126 127 ret = __ide_end_request(drive, rq, uptodate, nr_bytes, 1); 128 129 spin_unlock_irqrestore(&ide_lock, flags); 130 return ret; 131} 132EXPORT_SYMBOL(ide_end_request); 133 134/* 135 * Power Management state machine. This one is rather trivial for now, 136 * we should probably add more, like switching back to PIO on suspend 137 * to help some BIOSes, re-do the door locking on resume, etc... 138 */ 139 140enum { 141 ide_pm_flush_cache = ide_pm_state_start_suspend, 142 idedisk_pm_standby, 143 144 idedisk_pm_restore_pio = ide_pm_state_start_resume, 145 idedisk_pm_idle, 146 ide_pm_restore_dma, 147}; 148 149static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error) 150{ 151 struct request_pm_state *pm = rq->data; 152 153 if (drive->media != ide_disk) 154 return; 155 156 switch (pm->pm_step) { 157 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */ 158 if (pm->pm_state == PM_EVENT_FREEZE) 159 pm->pm_step = ide_pm_state_completed; 160 else 161 pm->pm_step = idedisk_pm_standby; 162 break; 163 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */ 164 pm->pm_step = ide_pm_state_completed; 165 break; 166 case idedisk_pm_restore_pio: /* Resume step 1 complete */ 167 pm->pm_step = idedisk_pm_idle; 168 break; 169 case idedisk_pm_idle: /* Resume step 2 (idle) complete */ 170 pm->pm_step = ide_pm_restore_dma; 171 break; 172 } 173} 174 175static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq) 176{ 177 struct request_pm_state *pm = rq->data; 178 ide_task_t *args = rq->special; 179 180 memset(args, 0, sizeof(*args)); 181 182 switch (pm->pm_step) { 183 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */ 184 if (drive->media != ide_disk) 185 break; 186 /* Not supported? Switch to next step now. */ 187 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) { 188 ide_complete_power_step(drive, rq, 0, 0); 189 return ide_stopped; 190 } 191 if (ide_id_has_flush_cache_ext(drive->id)) 192 args->tf.command = WIN_FLUSH_CACHE_EXT; 193 else 194 args->tf.command = WIN_FLUSH_CACHE; 195 goto out_do_tf; 196 197 case idedisk_pm_standby: /* Suspend step 2 (standby) */ 198 args->tf.command = WIN_STANDBYNOW1; 199 goto out_do_tf; 200 201 case idedisk_pm_restore_pio: /* Resume step 1 (restore PIO) */ 202 ide_set_max_pio(drive); 203 /* 204 * skip idedisk_pm_idle for ATAPI devices 205 */ 206 if (drive->media != ide_disk) 207 pm->pm_step = ide_pm_restore_dma; 208 else 209 ide_complete_power_step(drive, rq, 0, 0); 210 return ide_stopped; 211 212 case idedisk_pm_idle: /* Resume step 2 (idle) */ 213 args->tf.command = WIN_IDLEIMMEDIATE; 214 goto out_do_tf; 215 216 case ide_pm_restore_dma: /* Resume step 3 (restore DMA) */ 217 /* 218 * Right now, all we do is call ide_set_dma(drive), 219 * we could be smarter and check for current xfer_speed 220 * in struct drive etc... 221 */ 222 if (drive->hwif->dma_host_set == NULL) 223 break; 224 /* 225 * TODO: respect ->using_dma setting 226 */ 227 ide_set_dma(drive); 228 break; 229 } 230 pm->pm_step = ide_pm_state_completed; 231 return ide_stopped; 232 233out_do_tf: 234 args->tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE; 235 args->data_phase = TASKFILE_NO_DATA; 236 return do_rw_taskfile(drive, args); 237} 238 239/** 240 * ide_end_dequeued_request - complete an IDE I/O 241 * @drive: IDE device for the I/O 242 * @uptodate: 243 * @nr_sectors: number of sectors completed 244 * 245 * Complete an I/O that is no longer on the request queue. This 246 * typically occurs when we pull the request and issue a REQUEST_SENSE. 247 * We must still finish the old request but we must not tamper with the 248 * queue in the meantime. 249 * 250 * NOTE: This path does not handle barrier, but barrier is not supported 251 * on ide-cd anyway. 252 */ 253 254int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq, 255 int uptodate, int nr_sectors) 256{ 257 unsigned long flags; 258 int ret; 259 260 spin_lock_irqsave(&ide_lock, flags); 261 BUG_ON(!blk_rq_started(rq)); 262 ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0); 263 spin_unlock_irqrestore(&ide_lock, flags); 264 265 return ret; 266} 267EXPORT_SYMBOL_GPL(ide_end_dequeued_request); 268 269 270/** 271 * ide_complete_pm_request - end the current Power Management request 272 * @drive: target drive 273 * @rq: request 274 * 275 * This function cleans up the current PM request and stops the queue 276 * if necessary. 277 */ 278static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq) 279{ 280 unsigned long flags; 281 282#ifdef DEBUG_PM 283 printk("%s: completing PM request, %s\n", drive->name, 284 blk_pm_suspend_request(rq) ? "suspend" : "resume"); 285#endif 286 spin_lock_irqsave(&ide_lock, flags); 287 if (blk_pm_suspend_request(rq)) { 288 blk_stop_queue(drive->queue); 289 } else { 290 drive->blocked = 0; 291 blk_start_queue(drive->queue); 292 } 293 blkdev_dequeue_request(rq); 294 HWGROUP(drive)->rq = NULL; 295 end_that_request_last(rq, 1); 296 spin_unlock_irqrestore(&ide_lock, flags); 297} 298 299void ide_tf_read(ide_drive_t *drive, ide_task_t *task) 300{ 301 ide_hwif_t *hwif = drive->hwif; 302 struct ide_taskfile *tf = &task->tf; 303 304 if (task->tf_flags & IDE_TFLAG_IN_DATA) { 305 u16 data = hwif->INW(IDE_DATA_REG); 306 307 tf->data = data & 0xff; 308 tf->hob_data = (data >> 8) & 0xff; 309 } 310 311 /* be sure we're looking at the low order bits */ 312 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG); 313 314 if (task->tf_flags & IDE_TFLAG_IN_NSECT) 315 tf->nsect = hwif->INB(IDE_NSECTOR_REG); 316 if (task->tf_flags & IDE_TFLAG_IN_LBAL) 317 tf->lbal = hwif->INB(IDE_SECTOR_REG); 318 if (task->tf_flags & IDE_TFLAG_IN_LBAM) 319 tf->lbam = hwif->INB(IDE_LCYL_REG); 320 if (task->tf_flags & IDE_TFLAG_IN_LBAH) 321 tf->lbah = hwif->INB(IDE_HCYL_REG); 322 if (task->tf_flags & IDE_TFLAG_IN_DEVICE) 323 tf->device = hwif->INB(IDE_SELECT_REG); 324 325 if (task->tf_flags & IDE_TFLAG_LBA48) { 326 hwif->OUTB(drive->ctl | 0x80, IDE_CONTROL_REG); 327 328 if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE) 329 tf->hob_feature = hwif->INB(IDE_FEATURE_REG); 330 if (task->tf_flags & IDE_TFLAG_IN_HOB_NSECT) 331 tf->hob_nsect = hwif->INB(IDE_NSECTOR_REG); 332 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAL) 333 tf->hob_lbal = hwif->INB(IDE_SECTOR_REG); 334 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAM) 335 tf->hob_lbam = hwif->INB(IDE_LCYL_REG); 336 if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAH) 337 tf->hob_lbah = hwif->INB(IDE_HCYL_REG); 338 } 339} 340 341/** 342 * ide_end_drive_cmd - end an explicit drive command 343 * @drive: command 344 * @stat: status bits 345 * @err: error bits 346 * 347 * Clean up after success/failure of an explicit drive command. 348 * These get thrown onto the queue so they are synchronized with 349 * real I/O operations on the drive. 350 * 351 * In LBA48 mode we have to read the register set twice to get 352 * all the extra information out. 353 */ 354 355void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) 356{ 357 ide_hwif_t *hwif = HWIF(drive); 358 unsigned long flags; 359 struct request *rq; 360 361 spin_lock_irqsave(&ide_lock, flags); 362 rq = HWGROUP(drive)->rq; 363 spin_unlock_irqrestore(&ide_lock, flags); 364 365 if (rq->cmd_type == REQ_TYPE_ATA_CMD) { 366 u8 *args = (u8 *) rq->buffer; 367 if (rq->errors == 0) 368 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 369 370 if (args) { 371 args[0] = stat; 372 args[1] = err; 373 /* be sure we're looking at the low order bits */ 374 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG); 375 args[2] = hwif->INB(IDE_NSECTOR_REG); 376 } 377 } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 378 ide_task_t *args = (ide_task_t *) rq->special; 379 if (rq->errors == 0) 380 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 381 382 if (args) { 383 struct ide_taskfile *tf = &args->tf; 384 385 tf->error = err; 386 tf->status = stat; 387 388 ide_tf_read(drive, args); 389 } 390 } else if (blk_pm_request(rq)) { 391 struct request_pm_state *pm = rq->data; 392#ifdef DEBUG_PM 393 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n", 394 drive->name, rq->pm->pm_step, stat, err); 395#endif 396 ide_complete_power_step(drive, rq, stat, err); 397 if (pm->pm_step == ide_pm_state_completed) 398 ide_complete_pm_request(drive, rq); 399 return; 400 } 401 402 spin_lock_irqsave(&ide_lock, flags); 403 blkdev_dequeue_request(rq); 404 HWGROUP(drive)->rq = NULL; 405 rq->errors = err; 406 end_that_request_last(rq, !rq->errors); 407 spin_unlock_irqrestore(&ide_lock, flags); 408} 409 410EXPORT_SYMBOL(ide_end_drive_cmd); 411 412/** 413 * try_to_flush_leftover_data - flush junk 414 * @drive: drive to flush 415 * 416 * try_to_flush_leftover_data() is invoked in response to a drive 417 * unexpectedly having its DRQ_STAT bit set. As an alternative to 418 * resetting the drive, this routine tries to clear the condition 419 * by read a sector's worth of data from the drive. Of course, 420 * this may not help if the drive is *waiting* for data from *us*. 421 */ 422static void try_to_flush_leftover_data (ide_drive_t *drive) 423{ 424 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS; 425 426 if (drive->media != ide_disk) 427 return; 428 while (i > 0) { 429 u32 buffer[16]; 430 u32 wcount = (i > 16) ? 16 : i; 431 432 i -= wcount; 433 HWIF(drive)->ata_input_data(drive, buffer, wcount); 434 } 435} 436 437static void ide_kill_rq(ide_drive_t *drive, struct request *rq) 438{ 439 if (rq->rq_disk) { 440 ide_driver_t *drv; 441 442 drv = *(ide_driver_t **)rq->rq_disk->private_data; 443 drv->end_request(drive, 0, 0); 444 } else 445 ide_end_request(drive, 0, 0); 446} 447 448static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 449{ 450 ide_hwif_t *hwif = drive->hwif; 451 452 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 453 /* other bits are useless when BUSY */ 454 rq->errors |= ERROR_RESET; 455 } else if (stat & ERR_STAT) { 456 /* err has different meaning on cdrom and tape */ 457 if (err == ABRT_ERR) { 458 if (drive->select.b.lba && 459 /* some newer drives don't support WIN_SPECIFY */ 460 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY) 461 return ide_stopped; 462 } else if ((err & BAD_CRC) == BAD_CRC) { 463 /* UDMA crc error, just retry the operation */ 464 drive->crc_count++; 465 } else if (err & (BBD_ERR | ECC_ERR)) { 466 /* retries won't help these */ 467 rq->errors = ERROR_MAX; 468 } else if (err & TRK0_ERR) { 469 /* help it find track zero */ 470 rq->errors |= ERROR_RECAL; 471 } 472 } 473 474 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ && 475 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) 476 try_to_flush_leftover_data(drive); 477 478 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) { 479 ide_kill_rq(drive, rq); 480 return ide_stopped; 481 } 482 483 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 484 rq->errors |= ERROR_RESET; 485 486 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 487 ++rq->errors; 488 return ide_do_reset(drive); 489 } 490 491 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) 492 drive->special.b.recalibrate = 1; 493 494 ++rq->errors; 495 496 return ide_stopped; 497} 498 499static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 500{ 501 ide_hwif_t *hwif = drive->hwif; 502 503 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 504 /* other bits are useless when BUSY */ 505 rq->errors |= ERROR_RESET; 506 } else { 507 /* add decoding error stuff */ 508 } 509 510 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 511 /* force an abort */ 512 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 513 514 if (rq->errors >= ERROR_MAX) { 515 ide_kill_rq(drive, rq); 516 } else { 517 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 518 ++rq->errors; 519 return ide_do_reset(drive); 520 } 521 ++rq->errors; 522 } 523 524 return ide_stopped; 525} 526 527ide_startstop_t 528__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 529{ 530 if (drive->media == ide_disk) 531 return ide_ata_error(drive, rq, stat, err); 532 return ide_atapi_error(drive, rq, stat, err); 533} 534 535EXPORT_SYMBOL_GPL(__ide_error); 536 537/** 538 * ide_error - handle an error on the IDE 539 * @drive: drive the error occurred on 540 * @msg: message to report 541 * @stat: status bits 542 * 543 * ide_error() takes action based on the error returned by the drive. 544 * For normal I/O that may well include retries. We deal with 545 * both new-style (taskfile) and old style command handling here. 546 * In the case of taskfile command handling there is work left to 547 * do 548 */ 549 550ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) 551{ 552 struct request *rq; 553 u8 err; 554 555 err = ide_dump_status(drive, msg, stat); 556 557 if ((rq = HWGROUP(drive)->rq) == NULL) 558 return ide_stopped; 559 560 /* retry only "normal" I/O: */ 561 if (!blk_fs_request(rq)) { 562 rq->errors = 1; 563 ide_end_drive_cmd(drive, stat, err); 564 return ide_stopped; 565 } 566 567 if (rq->rq_disk) { 568 ide_driver_t *drv; 569 570 drv = *(ide_driver_t **)rq->rq_disk->private_data; 571 return drv->error(drive, rq, stat, err); 572 } else 573 return __ide_error(drive, rq, stat, err); 574} 575 576EXPORT_SYMBOL_GPL(ide_error); 577 578ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) 579{ 580 if (drive->media != ide_disk) 581 rq->errors |= ERROR_RESET; 582 583 ide_kill_rq(drive, rq); 584 585 return ide_stopped; 586} 587 588EXPORT_SYMBOL_GPL(__ide_abort); 589 590/** 591 * ide_abort - abort pending IDE operations 592 * @drive: drive the error occurred on 593 * @msg: message to report 594 * 595 * ide_abort kills and cleans up when we are about to do a 596 * host initiated reset on active commands. Longer term we 597 * want handlers to have sensible abort handling themselves 598 * 599 * This differs fundamentally from ide_error because in 600 * this case the command is doing just fine when we 601 * blow it away. 602 */ 603 604ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) 605{ 606 struct request *rq; 607 608 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) 609 return ide_stopped; 610 611 /* retry only "normal" I/O: */ 612 if (!blk_fs_request(rq)) { 613 rq->errors = 1; 614 ide_end_drive_cmd(drive, BUSY_STAT, 0); 615 return ide_stopped; 616 } 617 618 if (rq->rq_disk) { 619 ide_driver_t *drv; 620 621 drv = *(ide_driver_t **)rq->rq_disk->private_data; 622 return drv->abort(drive, rq); 623 } else 624 return __ide_abort(drive, rq); 625} 626 627/** 628 * drive_cmd_intr - drive command completion interrupt 629 * @drive: drive the completion interrupt occurred on 630 * 631 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD. 632 * We do any necessary data reading and then wait for the drive to 633 * go non busy. At that point we may read the error data and complete 634 * the request 635 */ 636 637static ide_startstop_t drive_cmd_intr (ide_drive_t *drive) 638{ 639 struct request *rq = HWGROUP(drive)->rq; 640 ide_hwif_t *hwif = HWIF(drive); 641 u8 *args = (u8 *)rq->buffer, pio_in = (args && args[3]) ? 1 : 0, stat; 642 643 if (pio_in) { 644 u8 io_32bit = drive->io_32bit; 645 stat = hwif->INB(IDE_STATUS_REG); 646 if ((stat & DRQ_STAT) == 0) 647 goto out; 648 drive->io_32bit = 0; 649 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS); 650 drive->io_32bit = io_32bit; 651 stat = wait_drive_not_busy(drive); 652 } else { 653 local_irq_enable_in_hardirq(); 654 stat = hwif->INB(IDE_STATUS_REG); 655 } 656out: 657 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) 658 return ide_error(drive, "drive_cmd", stat); 659 /* calls ide_end_drive_cmd */ 660 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG)); 661 return ide_stopped; 662} 663 664static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 665{ 666 tf->nsect = drive->sect; 667 tf->lbal = drive->sect; 668 tf->lbam = drive->cyl; 669 tf->lbah = drive->cyl >> 8; 670 tf->device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA; 671 tf->command = WIN_SPECIFY; 672} 673 674static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 675{ 676 tf->nsect = drive->sect; 677 tf->command = WIN_RESTORE; 678} 679 680static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 681{ 682 tf->nsect = drive->mult_req; 683 tf->command = WIN_SETMULT; 684} 685 686static ide_startstop_t ide_disk_special(ide_drive_t *drive) 687{ 688 special_t *s = &drive->special; 689 ide_task_t args; 690 691 memset(&args, 0, sizeof(ide_task_t)); 692 args.data_phase = TASKFILE_NO_DATA; 693 694 if (s->b.set_geometry) { 695 s->b.set_geometry = 0; 696 ide_tf_set_specify_cmd(drive, &args.tf); 697 } else if (s->b.recalibrate) { 698 s->b.recalibrate = 0; 699 ide_tf_set_restore_cmd(drive, &args.tf); 700 } else if (s->b.set_multmode) { 701 s->b.set_multmode = 0; 702 if (drive->mult_req > drive->id->max_multsect) 703 drive->mult_req = drive->id->max_multsect; 704 ide_tf_set_setmult_cmd(drive, &args.tf); 705 } else if (s->all) { 706 int special = s->all; 707 s->all = 0; 708 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); 709 return ide_stopped; 710 } 711 712 args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE | 713 IDE_TFLAG_CUSTOM_HANDLER; 714 715 do_rw_taskfile(drive, &args); 716 717 return ide_started; 718} 719 720/* 721 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away 722 */ 723static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio) 724{ 725 switch (req_pio) { 726 case 202: 727 case 201: 728 case 200: 729 case 102: 730 case 101: 731 case 100: 732 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0; 733 case 9: 734 case 8: 735 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0; 736 case 7: 737 case 6: 738 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0; 739 default: 740 return 0; 741 } 742} 743 744/** 745 * do_special - issue some special commands 746 * @drive: drive the command is for 747 * 748 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT 749 * commands to a drive. It used to do much more, but has been scaled 750 * back. 751 */ 752 753static ide_startstop_t do_special (ide_drive_t *drive) 754{ 755 special_t *s = &drive->special; 756 757#ifdef DEBUG 758 printk("%s: do_special: 0x%02x\n", drive->name, s->all); 759#endif 760 if (s->b.set_tune) { 761 ide_hwif_t *hwif = drive->hwif; 762 u8 req_pio = drive->tune_req; 763 764 s->b.set_tune = 0; 765 766 if (set_pio_mode_abuse(drive->hwif, req_pio)) { 767 768 if (hwif->set_pio_mode == NULL) 769 return ide_stopped; 770 771 /* 772 * take ide_lock for drive->[no_]unmask/[no_]io_32bit 773 */ 774 if (req_pio == 8 || req_pio == 9) { 775 unsigned long flags; 776 777 spin_lock_irqsave(&ide_lock, flags); 778 hwif->set_pio_mode(drive, req_pio); 779 spin_unlock_irqrestore(&ide_lock, flags); 780 } else 781 hwif->set_pio_mode(drive, req_pio); 782 } else { 783 int keep_dma = drive->using_dma; 784 785 ide_set_pio(drive, req_pio); 786 787 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) { 788 if (keep_dma) 789 ide_dma_on(drive); 790 } 791 } 792 793 return ide_stopped; 794 } else { 795 if (drive->media == ide_disk) 796 return ide_disk_special(drive); 797 798 s->all = 0; 799 drive->mult_req = 0; 800 return ide_stopped; 801 } 802} 803 804void ide_map_sg(ide_drive_t *drive, struct request *rq) 805{ 806 ide_hwif_t *hwif = drive->hwif; 807 struct scatterlist *sg = hwif->sg_table; 808 809 if (hwif->sg_mapped) /* needed by ide-scsi */ 810 return; 811 812 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) { 813 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); 814 } else { 815 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); 816 hwif->sg_nents = 1; 817 } 818} 819 820EXPORT_SYMBOL_GPL(ide_map_sg); 821 822void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) 823{ 824 ide_hwif_t *hwif = drive->hwif; 825 826 hwif->nsect = hwif->nleft = rq->nr_sectors; 827 hwif->cursg_ofs = 0; 828 hwif->cursg = NULL; 829} 830 831EXPORT_SYMBOL_GPL(ide_init_sg_cmd); 832 833/** 834 * execute_drive_command - issue special drive command 835 * @drive: the drive to issue the command on 836 * @rq: the request structure holding the command 837 * 838 * execute_drive_cmd() issues a special drive command, usually 839 * initiated by ioctl() from the external hdparm program. The 840 * command can be a drive command, drive task or taskfile 841 * operation. Weirdly you can call it with NULL to wait for 842 * all commands to finish. Don't do this as that is due to change 843 */ 844 845static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, 846 struct request *rq) 847{ 848 ide_hwif_t *hwif = HWIF(drive); 849 u8 *args = rq->buffer; 850 ide_task_t ltask; 851 struct ide_taskfile *tf = <ask.tf; 852 853 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 854 ide_task_t *task = rq->special; 855 856 if (task == NULL) 857 goto done; 858 859 hwif->data_phase = task->data_phase; 860 861 switch (hwif->data_phase) { 862 case TASKFILE_MULTI_OUT: 863 case TASKFILE_OUT: 864 case TASKFILE_MULTI_IN: 865 case TASKFILE_IN: 866 ide_init_sg_cmd(drive, rq); 867 ide_map_sg(drive, rq); 868 default: 869 break; 870 } 871 872 return do_rw_taskfile(drive, task); 873 } 874 875 if (args == NULL) 876 goto done; 877 878 memset(<ask, 0, sizeof(ltask)); 879 if (rq->cmd_type == REQ_TYPE_ATA_CMD) { 880#ifdef DEBUG 881 printk("%s: DRIVE_CMD\n", drive->name); 882#endif 883 tf->feature = args[2]; 884 if (args[0] == WIN_SMART) { 885 tf->nsect = args[3]; 886 tf->lbal = args[1]; 887 tf->lbam = 0x4f; 888 tf->lbah = 0xc2; 889 ltask.tf_flags = IDE_TFLAG_OUT_TF; 890 } else { 891 tf->nsect = args[1]; 892 ltask.tf_flags = IDE_TFLAG_OUT_FEATURE | 893 IDE_TFLAG_OUT_NSECT; 894 } 895 } 896 tf->command = args[0]; 897 ide_tf_load(drive, <ask); 898 ide_execute_command(drive, args[0], &drive_cmd_intr, WAIT_WORSTCASE, NULL); 899 return ide_started; 900 901done: 902 /* 903 * NULL is actually a valid way of waiting for 904 * all current requests to be flushed from the queue. 905 */ 906#ifdef DEBUG 907 printk("%s: DRIVE_CMD (null)\n", drive->name); 908#endif 909 ide_end_drive_cmd(drive, 910 hwif->INB(IDE_STATUS_REG), 911 hwif->INB(IDE_ERROR_REG)); 912 return ide_stopped; 913} 914 915static void ide_check_pm_state(ide_drive_t *drive, struct request *rq) 916{ 917 struct request_pm_state *pm = rq->data; 918 919 if (blk_pm_suspend_request(rq) && 920 pm->pm_step == ide_pm_state_start_suspend) 921 /* Mark drive blocked when starting the suspend sequence. */ 922 drive->blocked = 1; 923 else if (blk_pm_resume_request(rq) && 924 pm->pm_step == ide_pm_state_start_resume) { 925 /* 926 * The first thing we do on wakeup is to wait for BSY bit to 927 * go away (with a looong timeout) as a drive on this hwif may 928 * just be POSTing itself. 929 * We do that before even selecting as the "other" device on 930 * the bus may be broken enough to walk on our toes at this 931 * point. 932 */ 933 int rc; 934#ifdef DEBUG_PM 935 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); 936#endif 937 rc = ide_wait_not_busy(HWIF(drive), 35000); 938 if (rc) 939 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); 940 SELECT_DRIVE(drive); 941 ide_set_irq(drive, 1); 942 rc = ide_wait_not_busy(HWIF(drive), 100000); 943 if (rc) 944 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); 945 } 946} 947 948/** 949 * start_request - start of I/O and command issuing for IDE 950 * 951 * start_request() initiates handling of a new I/O request. It 952 * accepts commands and I/O (read/write) requests. It also does 953 * the final remapping for weird stuff like EZDrive. Once 954 * device mapper can work sector level the EZDrive stuff can go away 955 * 956 * FIXME: this function needs a rename 957 */ 958 959static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) 960{ 961 ide_startstop_t startstop; 962 sector_t block; 963 964 BUG_ON(!blk_rq_started(rq)); 965 966#ifdef DEBUG 967 printk("%s: start_request: current=0x%08lx\n", 968 HWIF(drive)->name, (unsigned long) rq); 969#endif 970 971 /* bail early if we've exceeded max_failures */ 972 if (drive->max_failures && (drive->failures > drive->max_failures)) { 973 rq->cmd_flags |= REQ_FAILED; 974 goto kill_rq; 975 } 976 977 block = rq->sector; 978 if (blk_fs_request(rq) && 979 (drive->media == ide_disk || drive->media == ide_floppy)) { 980 block += drive->sect0; 981 } 982 /* Yecch - this will shift the entire interval, 983 possibly killing some innocent following sector */ 984 if (block == 0 && drive->remap_0_to_1 == 1) 985 block = 1; /* redirect MBR access to EZ-Drive partn table */ 986 987 if (blk_pm_request(rq)) 988 ide_check_pm_state(drive, rq); 989 990 SELECT_DRIVE(drive); 991 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { 992 printk(KERN_ERR "%s: drive not ready for command\n", drive->name); 993 return startstop; 994 } 995 if (!drive->special.all) { 996 ide_driver_t *drv; 997 998 /* 999 * We reset the drive so we need to issue a SETFEATURES. 1000 * Do it _after_ do_special() restored device parameters. 1001 */ 1002 if (drive->current_speed == 0xff) 1003 ide_config_drive_speed(drive, drive->desired_speed); 1004 1005 if (rq->cmd_type == REQ_TYPE_ATA_CMD || 1006 rq->cmd_type == REQ_TYPE_ATA_TASKFILE) 1007 return execute_drive_cmd(drive, rq); 1008 else if (blk_pm_request(rq)) { 1009 struct request_pm_state *pm = rq->data; 1010#ifdef DEBUG_PM 1011 printk("%s: start_power_step(step: %d)\n", 1012 drive->name, rq->pm->pm_step); 1013#endif 1014 startstop = ide_start_power_step(drive, rq); 1015 if (startstop == ide_stopped && 1016 pm->pm_step == ide_pm_state_completed) 1017 ide_complete_pm_request(drive, rq); 1018 return startstop; 1019 } 1020 1021 drv = *(ide_driver_t **)rq->rq_disk->private_data; 1022 return drv->do_request(drive, rq, block); 1023 } 1024 return do_special(drive); 1025kill_rq: 1026 ide_kill_rq(drive, rq); 1027 return ide_stopped; 1028} 1029 1030/** 1031 * ide_stall_queue - pause an IDE device 1032 * @drive: drive to stall 1033 * @timeout: time to stall for (jiffies) 1034 * 1035 * ide_stall_queue() can be used by a drive to give excess bandwidth back 1036 * to the hwgroup by sleeping for timeout jiffies. 1037 */ 1038 1039void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) 1040{ 1041 if (timeout > WAIT_WORSTCASE) 1042 timeout = WAIT_WORSTCASE; 1043 drive->sleep = timeout + jiffies; 1044 drive->sleeping = 1; 1045} 1046 1047EXPORT_SYMBOL(ide_stall_queue); 1048 1049#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) 1050 1051/** 1052 * choose_drive - select a drive to service 1053 * @hwgroup: hardware group to select on 1054 * 1055 * choose_drive() selects the next drive which will be serviced. 1056 * This is necessary because the IDE layer can't issue commands 1057 * to both drives on the same cable, unlike SCSI. 1058 */ 1059 1060static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) 1061{ 1062 ide_drive_t *drive, *best; 1063 1064repeat: 1065 best = NULL; 1066 drive = hwgroup->drive; 1067 1068 /* 1069 * drive is doing pre-flush, ordered write, post-flush sequence. even 1070 * though that is 3 requests, it must be seen as a single transaction. 1071 * we must not preempt this drive until that is complete 1072 */ 1073 if (blk_queue_flushing(drive->queue)) { 1074 /* 1075 * small race where queue could get replugged during 1076 * the 3-request flush cycle, just yank the plug since 1077 * we want it to finish asap 1078 */ 1079 blk_remove_plug(drive->queue); 1080 return drive; 1081 } 1082 1083 do { 1084 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) 1085 && !elv_queue_empty(drive->queue)) { 1086 if (!best 1087 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) 1088 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) 1089 { 1090 if (!blk_queue_plugged(drive->queue)) 1091 best = drive; 1092 } 1093 } 1094 } while ((drive = drive->next) != hwgroup->drive); 1095 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { 1096 long t = (signed long)(WAKEUP(best) - jiffies); 1097 if (t >= WAIT_MIN_SLEEP) { 1098 /* 1099 * We *may* have some time to spare, but first let's see if 1100 * someone can potentially benefit from our nice mood today.. 1101 */ 1102 drive = best->next; 1103 do { 1104 if (!drive->sleeping 1105 && time_before(jiffies - best->service_time, WAKEUP(drive)) 1106 && time_before(WAKEUP(drive), jiffies + t)) 1107 { 1108 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); 1109 goto repeat; 1110 } 1111 } while ((drive = drive->next) != best); 1112 } 1113 } 1114 return best; 1115} 1116 1117/* 1118 * Issue a new request to a drive from hwgroup 1119 * Caller must have already done spin_lock_irqsave(&ide_lock, ..); 1120 * 1121 * A hwgroup is a serialized group of IDE interfaces. Usually there is 1122 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) 1123 * may have both interfaces in a single hwgroup to "serialize" access. 1124 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped 1125 * together into one hwgroup for serialized access. 1126 * 1127 * Note also that several hwgroups can end up sharing a single IRQ, 1128 * possibly along with many other devices. This is especially common in 1129 * PCI-based systems with off-board IDE controller cards. 1130 * 1131 * The IDE driver uses the single global ide_lock spinlock to protect 1132 * access to the request queues, and to protect the hwgroup->busy flag. 1133 * 1134 * The first thread into the driver for a particular hwgroup sets the 1135 * hwgroup->busy flag to indicate that this hwgroup is now active, 1136 * and then initiates processing of the top request from the request queue. 1137 * 1138 * Other threads attempting entry notice the busy setting, and will simply 1139 * queue their new requests and exit immediately. Note that hwgroup->busy 1140 * remains set even when the driver is merely awaiting the next interrupt. 1141 * Thus, the meaning is "this hwgroup is busy processing a request". 1142 * 1143 * When processing of a request completes, the completing thread or IRQ-handler 1144 * will start the next request from the queue. If no more work remains, 1145 * the driver will clear the hwgroup->busy flag and exit. 1146 * 1147 * The ide_lock (spinlock) is used to protect all access to the 1148 * hwgroup->busy flag, but is otherwise not needed for most processing in 1149 * the driver. This makes the driver much more friendlier to shared IRQs 1150 * than previous designs, while remaining 100% (?) SMP safe and capable. 1151 */ 1152static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) 1153{ 1154 ide_drive_t *drive; 1155 ide_hwif_t *hwif; 1156 struct request *rq; 1157 ide_startstop_t startstop; 1158 int loops = 0; 1159 1160 /* for atari only: POSSIBLY BROKEN HERE(?) */ 1161 ide_get_lock(ide_intr, hwgroup); 1162 1163 /* caller must own ide_lock */ 1164 BUG_ON(!irqs_disabled()); 1165 1166 while (!hwgroup->busy) { 1167 hwgroup->busy = 1; 1168 drive = choose_drive(hwgroup); 1169 if (drive == NULL) { 1170 int sleeping = 0; 1171 unsigned long sleep = 0; /* shut up, gcc */ 1172 hwgroup->rq = NULL; 1173 drive = hwgroup->drive; 1174 do { 1175 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { 1176 sleeping = 1; 1177 sleep = drive->sleep; 1178 } 1179 } while ((drive = drive->next) != hwgroup->drive); 1180 if (sleeping) { 1181 /* 1182 * Take a short snooze, and then wake up this hwgroup again. 1183 * This gives other hwgroups on the same a chance to 1184 * play fairly with us, just in case there are big differences 1185 * in relative throughputs.. don't want to hog the cpu too much. 1186 */ 1187 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) 1188 sleep = jiffies + WAIT_MIN_SLEEP; 1189#if 1 1190 if (timer_pending(&hwgroup->timer)) 1191 printk(KERN_CRIT "ide_set_handler: timer already active\n"); 1192#endif 1193 /* so that ide_timer_expiry knows what to do */ 1194 hwgroup->sleeping = 1; 1195 hwgroup->req_gen_timer = hwgroup->req_gen; 1196 mod_timer(&hwgroup->timer, sleep); 1197 /* we purposely leave hwgroup->busy==1 1198 * while sleeping */ 1199 } else { 1200 /* Ugly, but how can we sleep for the lock 1201 * otherwise? perhaps from tq_disk? 1202 */ 1203 1204 /* for atari only */ 1205 ide_release_lock(); 1206 hwgroup->busy = 0; 1207 } 1208 1209 /* no more work for this hwgroup (for now) */ 1210 return; 1211 } 1212 again: 1213 hwif = HWIF(drive); 1214 if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) { 1215 /* 1216 * set nIEN for previous hwif, drives in the 1217 * quirk_list may not like intr setups/cleanups 1218 */ 1219 if (drive->quirk_list != 1) 1220 ide_set_irq(drive, 0); 1221 } 1222 hwgroup->hwif = hwif; 1223 hwgroup->drive = drive; 1224 drive->sleeping = 0; 1225 drive->service_start = jiffies; 1226 1227 if (blk_queue_plugged(drive->queue)) { 1228 printk(KERN_ERR "ide: huh? queue was plugged!\n"); 1229 break; 1230 } 1231 1232 /* 1233 * we know that the queue isn't empty, but this can happen 1234 * if the q->prep_rq_fn() decides to kill a request 1235 */ 1236 rq = elv_next_request(drive->queue); 1237 if (!rq) { 1238 hwgroup->busy = 0; 1239 break; 1240 } 1241 1242 /* 1243 * Sanity: don't accept a request that isn't a PM request 1244 * if we are currently power managed. This is very important as 1245 * blk_stop_queue() doesn't prevent the elv_next_request() 1246 * above to return us whatever is in the queue. Since we call 1247 * ide_do_request() ourselves, we end up taking requests while 1248 * the queue is blocked... 1249 * 1250 * We let requests forced at head of queue with ide-preempt 1251 * though. I hope that doesn't happen too much, hopefully not 1252 * unless the subdriver triggers such a thing in its own PM 1253 * state machine. 1254 * 1255 * We count how many times we loop here to make sure we service 1256 * all drives in the hwgroup without looping for ever 1257 */ 1258 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) { 1259 drive = drive->next ? drive->next : hwgroup->drive; 1260 if (loops++ < 4 && !blk_queue_plugged(drive->queue)) 1261 goto again; 1262 /* We clear busy, there should be no pending ATA command at this point. */ 1263 hwgroup->busy = 0; 1264 break; 1265 } 1266 1267 hwgroup->rq = rq; 1268 1269 /* 1270 * Some systems have trouble with IDE IRQs arriving while 1271 * the driver is still setting things up. So, here we disable 1272 * the IRQ used by this interface while the request is being started. 1273 * This may look bad at first, but pretty much the same thing 1274 * happens anyway when any interrupt comes in, IDE or otherwise 1275 * -- the kernel masks the IRQ while it is being handled. 1276 */ 1277 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1278 disable_irq_nosync(hwif->irq); 1279 spin_unlock(&ide_lock); 1280 local_irq_enable_in_hardirq(); 1281 /* allow other IRQs while we start this request */ 1282 startstop = start_request(drive, rq); 1283 spin_lock_irq(&ide_lock); 1284 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1285 enable_irq(hwif->irq); 1286 if (startstop == ide_stopped) 1287 hwgroup->busy = 0; 1288 } 1289} 1290 1291/* 1292 * Passes the stuff to ide_do_request 1293 */ 1294void do_ide_request(struct request_queue *q) 1295{ 1296 ide_drive_t *drive = q->queuedata; 1297 1298 ide_do_request(HWGROUP(drive), IDE_NO_IRQ); 1299} 1300 1301/* 1302 * un-busy the hwgroup etc, and clear any pending DMA status. we want to 1303 * retry the current request in pio mode instead of risking tossing it 1304 * all away 1305 */ 1306static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) 1307{ 1308 ide_hwif_t *hwif = HWIF(drive); 1309 struct request *rq; 1310 ide_startstop_t ret = ide_stopped; 1311 1312 /* 1313 * end current dma transaction 1314 */ 1315 1316 if (error < 0) { 1317 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); 1318 (void)HWIF(drive)->ide_dma_end(drive); 1319 ret = ide_error(drive, "dma timeout error", 1320 hwif->INB(IDE_STATUS_REG)); 1321 } else { 1322 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); 1323 hwif->dma_timeout(drive); 1324 } 1325 1326 /* 1327 * disable dma for now, but remember that we did so because of 1328 * a timeout -- we'll reenable after we finish this next request 1329 * (or rather the first chunk of it) in pio. 1330 */ 1331 drive->retry_pio++; 1332 drive->state = DMA_PIO_RETRY; 1333 ide_dma_off_quietly(drive); 1334 1335 /* 1336 * un-busy drive etc (hwgroup->busy is cleared on return) and 1337 * make sure request is sane 1338 */ 1339 rq = HWGROUP(drive)->rq; 1340 1341 if (!rq) 1342 goto out; 1343 1344 HWGROUP(drive)->rq = NULL; 1345 1346 rq->errors = 0; 1347 1348 if (!rq->bio) 1349 goto out; 1350 1351 rq->sector = rq->bio->bi_sector; 1352 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; 1353 rq->hard_cur_sectors = rq->current_nr_sectors; 1354 rq->buffer = bio_data(rq->bio); 1355out: 1356 return ret; 1357} 1358 1359/** 1360 * ide_timer_expiry - handle lack of an IDE interrupt 1361 * @data: timer callback magic (hwgroup) 1362 * 1363 * An IDE command has timed out before the expected drive return 1364 * occurred. At this point we attempt to clean up the current 1365 * mess. If the current handler includes an expiry handler then 1366 * we invoke the expiry handler, and providing it is happy the 1367 * work is done. If that fails we apply generic recovery rules 1368 * invoking the handler and checking the drive DMA status. We 1369 * have an excessively incestuous relationship with the DMA 1370 * logic that wants cleaning up. 1371 */ 1372 1373void ide_timer_expiry (unsigned long data) 1374{ 1375 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; 1376 ide_handler_t *handler; 1377 ide_expiry_t *expiry; 1378 unsigned long flags; 1379 unsigned long wait = -1; 1380 1381 spin_lock_irqsave(&ide_lock, flags); 1382 1383 if (((handler = hwgroup->handler) == NULL) || 1384 (hwgroup->req_gen != hwgroup->req_gen_timer)) { 1385 /* 1386 * Either a marginal timeout occurred 1387 * (got the interrupt just as timer expired), 1388 * or we were "sleeping" to give other devices a chance. 1389 * Either way, we don't really want to complain about anything. 1390 */ 1391 if (hwgroup->sleeping) { 1392 hwgroup->sleeping = 0; 1393 hwgroup->busy = 0; 1394 } 1395 } else { 1396 ide_drive_t *drive = hwgroup->drive; 1397 if (!drive) { 1398 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); 1399 hwgroup->handler = NULL; 1400 } else { 1401 ide_hwif_t *hwif; 1402 ide_startstop_t startstop = ide_stopped; 1403 if (!hwgroup->busy) { 1404 hwgroup->busy = 1; /* paranoia */ 1405 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); 1406 } 1407 if ((expiry = hwgroup->expiry) != NULL) { 1408 /* continue */ 1409 if ((wait = expiry(drive)) > 0) { 1410 /* reset timer */ 1411 hwgroup->timer.expires = jiffies + wait; 1412 hwgroup->req_gen_timer = hwgroup->req_gen; 1413 add_timer(&hwgroup->timer); 1414 spin_unlock_irqrestore(&ide_lock, flags); 1415 return; 1416 } 1417 } 1418 hwgroup->handler = NULL; 1419 /* 1420 * We need to simulate a real interrupt when invoking 1421 * the handler() function, which means we need to 1422 * globally mask the specific IRQ: 1423 */ 1424 spin_unlock(&ide_lock); 1425 hwif = HWIF(drive); 1426 /* disable_irq_nosync ?? */ 1427 disable_irq(hwif->irq); 1428 /* local CPU only, 1429 * as if we were handling an interrupt */ 1430 local_irq_disable(); 1431 if (hwgroup->polling) { 1432 startstop = handler(drive); 1433 } else if (drive_is_ready(drive)) { 1434 if (drive->waiting_for_dma) 1435 hwgroup->hwif->dma_lost_irq(drive); 1436 (void)ide_ack_intr(hwif); 1437 printk(KERN_WARNING "%s: lost interrupt\n", drive->name); 1438 startstop = handler(drive); 1439 } else { 1440 if (drive->waiting_for_dma) { 1441 startstop = ide_dma_timeout_retry(drive, wait); 1442 } else 1443 startstop = 1444 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG)); 1445 } 1446 drive->service_time = jiffies - drive->service_start; 1447 spin_lock_irq(&ide_lock); 1448 enable_irq(hwif->irq); 1449 if (startstop == ide_stopped) 1450 hwgroup->busy = 0; 1451 } 1452 } 1453 ide_do_request(hwgroup, IDE_NO_IRQ); 1454 spin_unlock_irqrestore(&ide_lock, flags); 1455} 1456 1457/** 1458 * unexpected_intr - handle an unexpected IDE interrupt 1459 * @irq: interrupt line 1460 * @hwgroup: hwgroup being processed 1461 * 1462 * There's nothing really useful we can do with an unexpected interrupt, 1463 * other than reading the status register (to clear it), and logging it. 1464 * There should be no way that an irq can happen before we're ready for it, 1465 * so we needn't worry much about losing an "important" interrupt here. 1466 * 1467 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever 1468 * the drive enters "idle", "standby", or "sleep" mode, so if the status 1469 * looks "good", we just ignore the interrupt completely. 1470 * 1471 * This routine assumes __cli() is in effect when called. 1472 * 1473 * If an unexpected interrupt happens on irq15 while we are handling irq14 1474 * and if the two interfaces are "serialized" (CMD640), then it looks like 1475 * we could screw up by interfering with a new request being set up for 1476 * irq15. 1477 * 1478 * In reality, this is a non-issue. The new command is not sent unless 1479 * the drive is ready to accept one, in which case we know the drive is 1480 * not trying to interrupt us. And ide_set_handler() is always invoked 1481 * before completing the issuance of any new drive command, so we will not 1482 * be accidentally invoked as a result of any valid command completion 1483 * interrupt. 1484 * 1485 * Note that we must walk the entire hwgroup here. We know which hwif 1486 * is doing the current command, but we don't know which hwif burped 1487 * mysteriously. 1488 */ 1489 1490static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) 1491{ 1492 u8 stat; 1493 ide_hwif_t *hwif = hwgroup->hwif; 1494 1495 /* 1496 * handle the unexpected interrupt 1497 */ 1498 do { 1499 if (hwif->irq == irq) { 1500 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1501 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { 1502 /* Try to not flood the console with msgs */ 1503 static unsigned long last_msgtime, count; 1504 ++count; 1505 if (time_after(jiffies, last_msgtime + HZ)) { 1506 last_msgtime = jiffies; 1507 printk(KERN_ERR "%s%s: unexpected interrupt, " 1508 "status=0x%02x, count=%ld\n", 1509 hwif->name, 1510 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); 1511 } 1512 } 1513 } 1514 } while ((hwif = hwif->next) != hwgroup->hwif); 1515} 1516 1517/** 1518 * ide_intr - default IDE interrupt handler 1519 * @irq: interrupt number 1520 * @dev_id: hwif group 1521 * @regs: unused weirdness from the kernel irq layer 1522 * 1523 * This is the default IRQ handler for the IDE layer. You should 1524 * not need to override it. If you do be aware it is subtle in 1525 * places 1526 * 1527 * hwgroup->hwif is the interface in the group currently performing 1528 * a command. hwgroup->drive is the drive and hwgroup->handler is 1529 * the IRQ handler to call. As we issue a command the handlers 1530 * step through multiple states, reassigning the handler to the 1531 * next step in the process. Unlike a smart SCSI controller IDE 1532 * expects the main processor to sequence the various transfer 1533 * stages. We also manage a poll timer to catch up with most 1534 * timeout situations. There are still a few where the handlers 1535 * don't ever decide to give up. 1536 * 1537 * The handler eventually returns ide_stopped to indicate the 1538 * request completed. At this point we issue the next request 1539 * on the hwgroup and the process begins again. 1540 */ 1541 1542irqreturn_t ide_intr (int irq, void *dev_id) 1543{ 1544 unsigned long flags; 1545 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; 1546 ide_hwif_t *hwif; 1547 ide_drive_t *drive; 1548 ide_handler_t *handler; 1549 ide_startstop_t startstop; 1550 1551 spin_lock_irqsave(&ide_lock, flags); 1552 hwif = hwgroup->hwif; 1553 1554 if (!ide_ack_intr(hwif)) { 1555 spin_unlock_irqrestore(&ide_lock, flags); 1556 return IRQ_NONE; 1557 } 1558 1559 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { 1560 /* 1561 * Not expecting an interrupt from this drive. 1562 * That means this could be: 1563 * (1) an interrupt from another PCI device 1564 * sharing the same PCI INT# as us. 1565 * or (2) a drive just entered sleep or standby mode, 1566 * and is interrupting to let us know. 1567 * or (3) a spurious interrupt of unknown origin. 1568 * 1569 * For PCI, we cannot tell the difference, 1570 * so in that case we just ignore it and hope it goes away. 1571 * 1572 * FIXME: unexpected_intr should be hwif-> then we can 1573 * remove all the ifdef PCI crap 1574 */ 1575#ifdef CONFIG_BLK_DEV_IDEPCI 1576 if (hwif->pci_dev && !hwif->pci_dev->vendor) 1577#endif /* CONFIG_BLK_DEV_IDEPCI */ 1578 { 1579 /* 1580 * Probably not a shared PCI interrupt, 1581 * so we can safely try to do something about it: 1582 */ 1583 unexpected_intr(irq, hwgroup); 1584#ifdef CONFIG_BLK_DEV_IDEPCI 1585 } else { 1586 /* 1587 * Whack the status register, just in case 1588 * we have a leftover pending IRQ. 1589 */ 1590 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1591#endif /* CONFIG_BLK_DEV_IDEPCI */ 1592 } 1593 spin_unlock_irqrestore(&ide_lock, flags); 1594 return IRQ_NONE; 1595 } 1596 drive = hwgroup->drive; 1597 if (!drive) { 1598 /* 1599 * This should NEVER happen, and there isn't much 1600 * we could do about it here. 1601 * 1602 * [Note - this can occur if the drive is hot unplugged] 1603 */ 1604 spin_unlock_irqrestore(&ide_lock, flags); 1605 return IRQ_HANDLED; 1606 } 1607 if (!drive_is_ready(drive)) { 1608 /* 1609 * This happens regularly when we share a PCI IRQ with 1610 * another device. Unfortunately, it can also happen 1611 * with some buggy drives that trigger the IRQ before 1612 * their status register is up to date. Hopefully we have 1613 * enough advance overhead that the latter isn't a problem. 1614 */ 1615 spin_unlock_irqrestore(&ide_lock, flags); 1616 return IRQ_NONE; 1617 } 1618 if (!hwgroup->busy) { 1619 hwgroup->busy = 1; /* paranoia */ 1620 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); 1621 } 1622 hwgroup->handler = NULL; 1623 hwgroup->req_gen++; 1624 del_timer(&hwgroup->timer); 1625 spin_unlock(&ide_lock); 1626 1627 /* Some controllers might set DMA INTR no matter DMA or PIO; 1628 * bmdma status might need to be cleared even for 1629 * PIO interrupts to prevent spurious/lost irq. 1630 */ 1631 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma)) 1632 /* ide_dma_end() needs bmdma status for error checking. 1633 * So, skip clearing bmdma status here and leave it 1634 * to ide_dma_end() if this is dma interrupt. 1635 */ 1636 hwif->ide_dma_clear_irq(drive); 1637 1638 if (drive->unmask) 1639 local_irq_enable_in_hardirq(); 1640 /* service this interrupt, may set handler for next interrupt */ 1641 startstop = handler(drive); 1642 spin_lock_irq(&ide_lock); 1643 1644 /* 1645 * Note that handler() may have set things up for another 1646 * interrupt to occur soon, but it cannot happen until 1647 * we exit from this routine, because it will be the 1648 * same irq as is currently being serviced here, and Linux 1649 * won't allow another of the same (on any CPU) until we return. 1650 */ 1651 drive->service_time = jiffies - drive->service_start; 1652 if (startstop == ide_stopped) { 1653 if (hwgroup->handler == NULL) { /* paranoia */ 1654 hwgroup->busy = 0; 1655 ide_do_request(hwgroup, hwif->irq); 1656 } else { 1657 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " 1658 "on exit\n", drive->name); 1659 } 1660 } 1661 spin_unlock_irqrestore(&ide_lock, flags); 1662 return IRQ_HANDLED; 1663} 1664 1665/** 1666 * ide_init_drive_cmd - initialize a drive command request 1667 * @rq: request object 1668 * 1669 * Initialize a request before we fill it in and send it down to 1670 * ide_do_drive_cmd. Commands must be set up by this function. Right 1671 * now it doesn't do a lot, but if that changes abusers will have a 1672 * nasty surprise. 1673 */ 1674 1675void ide_init_drive_cmd (struct request *rq) 1676{ 1677 memset(rq, 0, sizeof(*rq)); 1678 rq->ref_count = 1; 1679} 1680 1681EXPORT_SYMBOL(ide_init_drive_cmd); 1682 1683/** 1684 * ide_do_drive_cmd - issue IDE special command 1685 * @drive: device to issue command 1686 * @rq: request to issue 1687 * @action: action for processing 1688 * 1689 * This function issues a special IDE device request 1690 * onto the request queue. 1691 * 1692 * If action is ide_wait, then the rq is queued at the end of the 1693 * request queue, and the function sleeps until it has been processed. 1694 * This is for use when invoked from an ioctl handler. 1695 * 1696 * If action is ide_preempt, then the rq is queued at the head of 1697 * the request queue, displacing the currently-being-processed 1698 * request and this function returns immediately without waiting 1699 * for the new rq to be completed. This is VERY DANGEROUS, and is 1700 * intended for careful use by the ATAPI tape/cdrom driver code. 1701 * 1702 * If action is ide_end, then the rq is queued at the end of the 1703 * request queue, and the function returns immediately without waiting 1704 * for the new rq to be completed. This is again intended for careful 1705 * use by the ATAPI tape/cdrom driver code. 1706 */ 1707 1708int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) 1709{ 1710 unsigned long flags; 1711 ide_hwgroup_t *hwgroup = HWGROUP(drive); 1712 DECLARE_COMPLETION_ONSTACK(wait); 1713 int where = ELEVATOR_INSERT_BACK, err; 1714 int must_wait = (action == ide_wait || action == ide_head_wait); 1715 1716 rq->errors = 0; 1717 1718 /* 1719 * we need to hold an extra reference to request for safe inspection 1720 * after completion 1721 */ 1722 if (must_wait) { 1723 rq->ref_count++; 1724 rq->end_io_data = &wait; 1725 rq->end_io = blk_end_sync_rq; 1726 } 1727 1728 spin_lock_irqsave(&ide_lock, flags); 1729 if (action == ide_preempt) 1730 hwgroup->rq = NULL; 1731 if (action == ide_preempt || action == ide_head_wait) { 1732 where = ELEVATOR_INSERT_FRONT; 1733 rq->cmd_flags |= REQ_PREEMPT; 1734 } 1735 __elv_add_request(drive->queue, rq, where, 0); 1736 ide_do_request(hwgroup, IDE_NO_IRQ); 1737 spin_unlock_irqrestore(&ide_lock, flags); 1738 1739 err = 0; 1740 if (must_wait) { 1741 wait_for_completion(&wait); 1742 if (rq->errors) 1743 err = -EIO; 1744 1745 blk_put_request(rq); 1746 } 1747 1748 return err; 1749} 1750 1751EXPORT_SYMBOL(ide_do_drive_cmd); 1752 1753void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma) 1754{ 1755 ide_task_t task; 1756 1757 memset(&task, 0, sizeof(task)); 1758 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM | 1759 IDE_TFLAG_OUT_FEATURE | tf_flags; 1760 task.tf.feature = dma; /* Use PIO/DMA */ 1761 task.tf.lbam = bcount & 0xff; 1762 task.tf.lbah = (bcount >> 8) & 0xff; 1763 1764 ide_tf_load(drive, &task); 1765} 1766 1767EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load); 1768