ide-io.c revision 81ca691981da718727281238b435dcf1528d2fda
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_OUT_TF | IDE_TFLAG_OUT_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 args[2] = hwif->INB(IDE_NSECTOR_REG); 374 } 375 } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 376 ide_task_t *args = (ide_task_t *) rq->special; 377 if (rq->errors == 0) 378 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 379 380 if (args) { 381 struct ide_taskfile *tf = &args->tf; 382 383 tf->error = err; 384 tf->status = stat; 385 386 args->tf_flags |= (IDE_TFLAG_IN_TF|IDE_TFLAG_IN_DEVICE); 387 if (args->tf_flags & IDE_TFLAG_LBA48) 388 args->tf_flags |= IDE_TFLAG_IN_HOB; 389 390 ide_tf_read(drive, args); 391 } 392 } else if (blk_pm_request(rq)) { 393 struct request_pm_state *pm = rq->data; 394#ifdef DEBUG_PM 395 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n", 396 drive->name, rq->pm->pm_step, stat, err); 397#endif 398 ide_complete_power_step(drive, rq, stat, err); 399 if (pm->pm_step == ide_pm_state_completed) 400 ide_complete_pm_request(drive, rq); 401 return; 402 } 403 404 spin_lock_irqsave(&ide_lock, flags); 405 blkdev_dequeue_request(rq); 406 HWGROUP(drive)->rq = NULL; 407 rq->errors = err; 408 end_that_request_last(rq, !rq->errors); 409 spin_unlock_irqrestore(&ide_lock, flags); 410} 411 412EXPORT_SYMBOL(ide_end_drive_cmd); 413 414/** 415 * try_to_flush_leftover_data - flush junk 416 * @drive: drive to flush 417 * 418 * try_to_flush_leftover_data() is invoked in response to a drive 419 * unexpectedly having its DRQ_STAT bit set. As an alternative to 420 * resetting the drive, this routine tries to clear the condition 421 * by read a sector's worth of data from the drive. Of course, 422 * this may not help if the drive is *waiting* for data from *us*. 423 */ 424static void try_to_flush_leftover_data (ide_drive_t *drive) 425{ 426 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS; 427 428 if (drive->media != ide_disk) 429 return; 430 while (i > 0) { 431 u32 buffer[16]; 432 u32 wcount = (i > 16) ? 16 : i; 433 434 i -= wcount; 435 HWIF(drive)->ata_input_data(drive, buffer, wcount); 436 } 437} 438 439static void ide_kill_rq(ide_drive_t *drive, struct request *rq) 440{ 441 if (rq->rq_disk) { 442 ide_driver_t *drv; 443 444 drv = *(ide_driver_t **)rq->rq_disk->private_data; 445 drv->end_request(drive, 0, 0); 446 } else 447 ide_end_request(drive, 0, 0); 448} 449 450static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 451{ 452 ide_hwif_t *hwif = drive->hwif; 453 454 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 455 /* other bits are useless when BUSY */ 456 rq->errors |= ERROR_RESET; 457 } else if (stat & ERR_STAT) { 458 /* err has different meaning on cdrom and tape */ 459 if (err == ABRT_ERR) { 460 if (drive->select.b.lba && 461 /* some newer drives don't support WIN_SPECIFY */ 462 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY) 463 return ide_stopped; 464 } else if ((err & BAD_CRC) == BAD_CRC) { 465 /* UDMA crc error, just retry the operation */ 466 drive->crc_count++; 467 } else if (err & (BBD_ERR | ECC_ERR)) { 468 /* retries won't help these */ 469 rq->errors = ERROR_MAX; 470 } else if (err & TRK0_ERR) { 471 /* help it find track zero */ 472 rq->errors |= ERROR_RECAL; 473 } 474 } 475 476 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ && 477 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) 478 try_to_flush_leftover_data(drive); 479 480 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) { 481 ide_kill_rq(drive, rq); 482 return ide_stopped; 483 } 484 485 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 486 rq->errors |= ERROR_RESET; 487 488 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 489 ++rq->errors; 490 return ide_do_reset(drive); 491 } 492 493 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) 494 drive->special.b.recalibrate = 1; 495 496 ++rq->errors; 497 498 return ide_stopped; 499} 500 501static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 502{ 503 ide_hwif_t *hwif = drive->hwif; 504 505 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 506 /* other bits are useless when BUSY */ 507 rq->errors |= ERROR_RESET; 508 } else { 509 /* add decoding error stuff */ 510 } 511 512 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 513 /* force an abort */ 514 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 515 516 if (rq->errors >= ERROR_MAX) { 517 ide_kill_rq(drive, rq); 518 } else { 519 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 520 ++rq->errors; 521 return ide_do_reset(drive); 522 } 523 ++rq->errors; 524 } 525 526 return ide_stopped; 527} 528 529ide_startstop_t 530__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 531{ 532 if (drive->media == ide_disk) 533 return ide_ata_error(drive, rq, stat, err); 534 return ide_atapi_error(drive, rq, stat, err); 535} 536 537EXPORT_SYMBOL_GPL(__ide_error); 538 539/** 540 * ide_error - handle an error on the IDE 541 * @drive: drive the error occurred on 542 * @msg: message to report 543 * @stat: status bits 544 * 545 * ide_error() takes action based on the error returned by the drive. 546 * For normal I/O that may well include retries. We deal with 547 * both new-style (taskfile) and old style command handling here. 548 * In the case of taskfile command handling there is work left to 549 * do 550 */ 551 552ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) 553{ 554 struct request *rq; 555 u8 err; 556 557 err = ide_dump_status(drive, msg, stat); 558 559 if ((rq = HWGROUP(drive)->rq) == NULL) 560 return ide_stopped; 561 562 /* retry only "normal" I/O: */ 563 if (!blk_fs_request(rq)) { 564 rq->errors = 1; 565 ide_end_drive_cmd(drive, stat, err); 566 return ide_stopped; 567 } 568 569 if (rq->rq_disk) { 570 ide_driver_t *drv; 571 572 drv = *(ide_driver_t **)rq->rq_disk->private_data; 573 return drv->error(drive, rq, stat, err); 574 } else 575 return __ide_error(drive, rq, stat, err); 576} 577 578EXPORT_SYMBOL_GPL(ide_error); 579 580ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) 581{ 582 if (drive->media != ide_disk) 583 rq->errors |= ERROR_RESET; 584 585 ide_kill_rq(drive, rq); 586 587 return ide_stopped; 588} 589 590EXPORT_SYMBOL_GPL(__ide_abort); 591 592/** 593 * ide_abort - abort pending IDE operations 594 * @drive: drive the error occurred on 595 * @msg: message to report 596 * 597 * ide_abort kills and cleans up when we are about to do a 598 * host initiated reset on active commands. Longer term we 599 * want handlers to have sensible abort handling themselves 600 * 601 * This differs fundamentally from ide_error because in 602 * this case the command is doing just fine when we 603 * blow it away. 604 */ 605 606ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) 607{ 608 struct request *rq; 609 610 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) 611 return ide_stopped; 612 613 /* retry only "normal" I/O: */ 614 if (!blk_fs_request(rq)) { 615 rq->errors = 1; 616 ide_end_drive_cmd(drive, BUSY_STAT, 0); 617 return ide_stopped; 618 } 619 620 if (rq->rq_disk) { 621 ide_driver_t *drv; 622 623 drv = *(ide_driver_t **)rq->rq_disk->private_data; 624 return drv->abort(drive, rq); 625 } else 626 return __ide_abort(drive, rq); 627} 628 629/** 630 * drive_cmd_intr - drive command completion interrupt 631 * @drive: drive the completion interrupt occurred on 632 * 633 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD. 634 * We do any necessary data reading and then wait for the drive to 635 * go non busy. At that point we may read the error data and complete 636 * the request 637 */ 638 639static ide_startstop_t drive_cmd_intr (ide_drive_t *drive) 640{ 641 struct request *rq = HWGROUP(drive)->rq; 642 ide_hwif_t *hwif = HWIF(drive); 643 u8 *args = (u8 *) rq->buffer; 644 u8 stat = hwif->INB(IDE_STATUS_REG); 645 int retries = 10; 646 647 local_irq_enable_in_hardirq(); 648 if (rq->cmd_type == REQ_TYPE_ATA_CMD && 649 (stat & DRQ_STAT) && args && args[3]) { 650 u8 io_32bit = drive->io_32bit; 651 drive->io_32bit = 0; 652 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS); 653 drive->io_32bit = io_32bit; 654 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--) 655 udelay(100); 656 } 657 658 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) 659 return ide_error(drive, "drive_cmd", stat); 660 /* calls ide_end_drive_cmd */ 661 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG)); 662 return ide_stopped; 663} 664 665static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 666{ 667 tf->nsect = drive->sect; 668 tf->lbal = drive->sect; 669 tf->lbam = drive->cyl; 670 tf->lbah = drive->cyl >> 8; 671 tf->device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA; 672 tf->command = WIN_SPECIFY; 673} 674 675static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 676{ 677 tf->nsect = drive->sect; 678 tf->command = WIN_RESTORE; 679} 680 681static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 682{ 683 tf->nsect = drive->mult_req; 684 tf->command = WIN_SETMULT; 685} 686 687static ide_startstop_t ide_disk_special(ide_drive_t *drive) 688{ 689 special_t *s = &drive->special; 690 ide_task_t args; 691 692 memset(&args, 0, sizeof(ide_task_t)); 693 args.data_phase = TASKFILE_NO_DATA; 694 695 if (s->b.set_geometry) { 696 s->b.set_geometry = 0; 697 ide_tf_set_specify_cmd(drive, &args.tf); 698 } else if (s->b.recalibrate) { 699 s->b.recalibrate = 0; 700 ide_tf_set_restore_cmd(drive, &args.tf); 701 } else if (s->b.set_multmode) { 702 s->b.set_multmode = 0; 703 if (drive->mult_req > drive->id->max_multsect) 704 drive->mult_req = drive->id->max_multsect; 705 ide_tf_set_setmult_cmd(drive, &args.tf); 706 } else if (s->all) { 707 int special = s->all; 708 s->all = 0; 709 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); 710 return ide_stopped; 711 } 712 713 args.tf_flags = IDE_TFLAG_OUT_TF | IDE_TFLAG_OUT_DEVICE | 714 IDE_TFLAG_CUSTOM_HANDLER; 715 716 do_rw_taskfile(drive, &args); 717 718 return ide_started; 719} 720 721/* 722 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away 723 */ 724static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio) 725{ 726 switch (req_pio) { 727 case 202: 728 case 201: 729 case 200: 730 case 102: 731 case 101: 732 case 100: 733 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0; 734 case 9: 735 case 8: 736 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0; 737 case 7: 738 case 6: 739 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0; 740 default: 741 return 0; 742 } 743} 744 745/** 746 * do_special - issue some special commands 747 * @drive: drive the command is for 748 * 749 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT 750 * commands to a drive. It used to do much more, but has been scaled 751 * back. 752 */ 753 754static ide_startstop_t do_special (ide_drive_t *drive) 755{ 756 special_t *s = &drive->special; 757 758#ifdef DEBUG 759 printk("%s: do_special: 0x%02x\n", drive->name, s->all); 760#endif 761 if (s->b.set_tune) { 762 ide_hwif_t *hwif = drive->hwif; 763 u8 req_pio = drive->tune_req; 764 765 s->b.set_tune = 0; 766 767 if (set_pio_mode_abuse(drive->hwif, req_pio)) { 768 769 if (hwif->set_pio_mode == NULL) 770 return ide_stopped; 771 772 /* 773 * take ide_lock for drive->[no_]unmask/[no_]io_32bit 774 */ 775 if (req_pio == 8 || req_pio == 9) { 776 unsigned long flags; 777 778 spin_lock_irqsave(&ide_lock, flags); 779 hwif->set_pio_mode(drive, req_pio); 780 spin_unlock_irqrestore(&ide_lock, flags); 781 } else 782 hwif->set_pio_mode(drive, req_pio); 783 } else { 784 int keep_dma = drive->using_dma; 785 786 ide_set_pio(drive, req_pio); 787 788 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) { 789 if (keep_dma) 790 ide_dma_on(drive); 791 } 792 } 793 794 return ide_stopped; 795 } else { 796 if (drive->media == ide_disk) 797 return ide_disk_special(drive); 798 799 s->all = 0; 800 drive->mult_req = 0; 801 return ide_stopped; 802 } 803} 804 805void ide_map_sg(ide_drive_t *drive, struct request *rq) 806{ 807 ide_hwif_t *hwif = drive->hwif; 808 struct scatterlist *sg = hwif->sg_table; 809 810 if (hwif->sg_mapped) /* needed by ide-scsi */ 811 return; 812 813 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) { 814 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); 815 } else { 816 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); 817 hwif->sg_nents = 1; 818 } 819} 820 821EXPORT_SYMBOL_GPL(ide_map_sg); 822 823void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) 824{ 825 ide_hwif_t *hwif = drive->hwif; 826 827 hwif->nsect = hwif->nleft = rq->nr_sectors; 828 hwif->cursg_ofs = 0; 829 hwif->cursg = NULL; 830} 831 832EXPORT_SYMBOL_GPL(ide_init_sg_cmd); 833 834/** 835 * execute_drive_command - issue special drive command 836 * @drive: the drive to issue the command on 837 * @rq: the request structure holding the command 838 * 839 * execute_drive_cmd() issues a special drive command, usually 840 * initiated by ioctl() from the external hdparm program. The 841 * command can be a drive command, drive task or taskfile 842 * operation. Weirdly you can call it with NULL to wait for 843 * all commands to finish. Don't do this as that is due to change 844 */ 845 846static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, 847 struct request *rq) 848{ 849 ide_hwif_t *hwif = HWIF(drive); 850 u8 *args = rq->buffer; 851 ide_task_t ltask; 852 struct ide_taskfile *tf = <ask.tf; 853 854 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 855 ide_task_t *task = rq->special; 856 857 if (task == NULL) 858 goto done; 859 860 hwif->data_phase = task->data_phase; 861 862 switch (hwif->data_phase) { 863 case TASKFILE_MULTI_OUT: 864 case TASKFILE_OUT: 865 case TASKFILE_MULTI_IN: 866 case TASKFILE_IN: 867 ide_init_sg_cmd(drive, rq); 868 ide_map_sg(drive, rq); 869 default: 870 break; 871 } 872 873 return do_rw_taskfile(drive, task); 874 } 875 876 if (args == NULL) 877 goto done; 878 879 memset(<ask, 0, sizeof(ltask)); 880 if (rq->cmd_type == REQ_TYPE_ATA_CMD) { 881#ifdef DEBUG 882 printk("%s: DRIVE_CMD\n", drive->name); 883#endif 884 tf->feature = args[2]; 885 if (args[0] == WIN_SMART) { 886 tf->nsect = args[3]; 887 tf->lbal = args[1]; 888 tf->lbam = 0x4f; 889 tf->lbah = 0xc2; 890 ltask.tf_flags = IDE_TFLAG_OUT_TF; 891 } else { 892 tf->nsect = args[1]; 893 ltask.tf_flags = IDE_TFLAG_OUT_FEATURE | 894 IDE_TFLAG_OUT_NSECT; 895 } 896 } 897 tf->command = args[0]; 898 ide_tf_load(drive, <ask); 899 ide_execute_command(drive, args[0], &drive_cmd_intr, WAIT_WORSTCASE, NULL); 900 return ide_started; 901 902done: 903 /* 904 * NULL is actually a valid way of waiting for 905 * all current requests to be flushed from the queue. 906 */ 907#ifdef DEBUG 908 printk("%s: DRIVE_CMD (null)\n", drive->name); 909#endif 910 ide_end_drive_cmd(drive, 911 hwif->INB(IDE_STATUS_REG), 912 hwif->INB(IDE_ERROR_REG)); 913 return ide_stopped; 914} 915 916static void ide_check_pm_state(ide_drive_t *drive, struct request *rq) 917{ 918 struct request_pm_state *pm = rq->data; 919 920 if (blk_pm_suspend_request(rq) && 921 pm->pm_step == ide_pm_state_start_suspend) 922 /* Mark drive blocked when starting the suspend sequence. */ 923 drive->blocked = 1; 924 else if (blk_pm_resume_request(rq) && 925 pm->pm_step == ide_pm_state_start_resume) { 926 /* 927 * The first thing we do on wakeup is to wait for BSY bit to 928 * go away (with a looong timeout) as a drive on this hwif may 929 * just be POSTing itself. 930 * We do that before even selecting as the "other" device on 931 * the bus may be broken enough to walk on our toes at this 932 * point. 933 */ 934 int rc; 935#ifdef DEBUG_PM 936 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); 937#endif 938 rc = ide_wait_not_busy(HWIF(drive), 35000); 939 if (rc) 940 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); 941 SELECT_DRIVE(drive); 942 ide_set_irq(drive, 1); 943 rc = ide_wait_not_busy(HWIF(drive), 100000); 944 if (rc) 945 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); 946 } 947} 948 949/** 950 * start_request - start of I/O and command issuing for IDE 951 * 952 * start_request() initiates handling of a new I/O request. It 953 * accepts commands and I/O (read/write) requests. It also does 954 * the final remapping for weird stuff like EZDrive. Once 955 * device mapper can work sector level the EZDrive stuff can go away 956 * 957 * FIXME: this function needs a rename 958 */ 959 960static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) 961{ 962 ide_startstop_t startstop; 963 sector_t block; 964 965 BUG_ON(!blk_rq_started(rq)); 966 967#ifdef DEBUG 968 printk("%s: start_request: current=0x%08lx\n", 969 HWIF(drive)->name, (unsigned long) rq); 970#endif 971 972 /* bail early if we've exceeded max_failures */ 973 if (drive->max_failures && (drive->failures > drive->max_failures)) { 974 rq->cmd_flags |= REQ_FAILED; 975 goto kill_rq; 976 } 977 978 block = rq->sector; 979 if (blk_fs_request(rq) && 980 (drive->media == ide_disk || drive->media == ide_floppy)) { 981 block += drive->sect0; 982 } 983 /* Yecch - this will shift the entire interval, 984 possibly killing some innocent following sector */ 985 if (block == 0 && drive->remap_0_to_1 == 1) 986 block = 1; /* redirect MBR access to EZ-Drive partn table */ 987 988 if (blk_pm_request(rq)) 989 ide_check_pm_state(drive, rq); 990 991 SELECT_DRIVE(drive); 992 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { 993 printk(KERN_ERR "%s: drive not ready for command\n", drive->name); 994 return startstop; 995 } 996 if (!drive->special.all) { 997 ide_driver_t *drv; 998 999 /* 1000 * We reset the drive so we need to issue a SETFEATURES. 1001 * Do it _after_ do_special() restored device parameters. 1002 */ 1003 if (drive->current_speed == 0xff) 1004 ide_config_drive_speed(drive, drive->desired_speed); 1005 1006 if (rq->cmd_type == REQ_TYPE_ATA_CMD || 1007 rq->cmd_type == REQ_TYPE_ATA_TASKFILE) 1008 return execute_drive_cmd(drive, rq); 1009 else if (blk_pm_request(rq)) { 1010 struct request_pm_state *pm = rq->data; 1011#ifdef DEBUG_PM 1012 printk("%s: start_power_step(step: %d)\n", 1013 drive->name, rq->pm->pm_step); 1014#endif 1015 startstop = ide_start_power_step(drive, rq); 1016 if (startstop == ide_stopped && 1017 pm->pm_step == ide_pm_state_completed) 1018 ide_complete_pm_request(drive, rq); 1019 return startstop; 1020 } 1021 1022 drv = *(ide_driver_t **)rq->rq_disk->private_data; 1023 return drv->do_request(drive, rq, block); 1024 } 1025 return do_special(drive); 1026kill_rq: 1027 ide_kill_rq(drive, rq); 1028 return ide_stopped; 1029} 1030 1031/** 1032 * ide_stall_queue - pause an IDE device 1033 * @drive: drive to stall 1034 * @timeout: time to stall for (jiffies) 1035 * 1036 * ide_stall_queue() can be used by a drive to give excess bandwidth back 1037 * to the hwgroup by sleeping for timeout jiffies. 1038 */ 1039 1040void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) 1041{ 1042 if (timeout > WAIT_WORSTCASE) 1043 timeout = WAIT_WORSTCASE; 1044 drive->sleep = timeout + jiffies; 1045 drive->sleeping = 1; 1046} 1047 1048EXPORT_SYMBOL(ide_stall_queue); 1049 1050#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) 1051 1052/** 1053 * choose_drive - select a drive to service 1054 * @hwgroup: hardware group to select on 1055 * 1056 * choose_drive() selects the next drive which will be serviced. 1057 * This is necessary because the IDE layer can't issue commands 1058 * to both drives on the same cable, unlike SCSI. 1059 */ 1060 1061static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) 1062{ 1063 ide_drive_t *drive, *best; 1064 1065repeat: 1066 best = NULL; 1067 drive = hwgroup->drive; 1068 1069 /* 1070 * drive is doing pre-flush, ordered write, post-flush sequence. even 1071 * though that is 3 requests, it must be seen as a single transaction. 1072 * we must not preempt this drive until that is complete 1073 */ 1074 if (blk_queue_flushing(drive->queue)) { 1075 /* 1076 * small race where queue could get replugged during 1077 * the 3-request flush cycle, just yank the plug since 1078 * we want it to finish asap 1079 */ 1080 blk_remove_plug(drive->queue); 1081 return drive; 1082 } 1083 1084 do { 1085 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) 1086 && !elv_queue_empty(drive->queue)) { 1087 if (!best 1088 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) 1089 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) 1090 { 1091 if (!blk_queue_plugged(drive->queue)) 1092 best = drive; 1093 } 1094 } 1095 } while ((drive = drive->next) != hwgroup->drive); 1096 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { 1097 long t = (signed long)(WAKEUP(best) - jiffies); 1098 if (t >= WAIT_MIN_SLEEP) { 1099 /* 1100 * We *may* have some time to spare, but first let's see if 1101 * someone can potentially benefit from our nice mood today.. 1102 */ 1103 drive = best->next; 1104 do { 1105 if (!drive->sleeping 1106 && time_before(jiffies - best->service_time, WAKEUP(drive)) 1107 && time_before(WAKEUP(drive), jiffies + t)) 1108 { 1109 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); 1110 goto repeat; 1111 } 1112 } while ((drive = drive->next) != best); 1113 } 1114 } 1115 return best; 1116} 1117 1118/* 1119 * Issue a new request to a drive from hwgroup 1120 * Caller must have already done spin_lock_irqsave(&ide_lock, ..); 1121 * 1122 * A hwgroup is a serialized group of IDE interfaces. Usually there is 1123 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) 1124 * may have both interfaces in a single hwgroup to "serialize" access. 1125 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped 1126 * together into one hwgroup for serialized access. 1127 * 1128 * Note also that several hwgroups can end up sharing a single IRQ, 1129 * possibly along with many other devices. This is especially common in 1130 * PCI-based systems with off-board IDE controller cards. 1131 * 1132 * The IDE driver uses the single global ide_lock spinlock to protect 1133 * access to the request queues, and to protect the hwgroup->busy flag. 1134 * 1135 * The first thread into the driver for a particular hwgroup sets the 1136 * hwgroup->busy flag to indicate that this hwgroup is now active, 1137 * and then initiates processing of the top request from the request queue. 1138 * 1139 * Other threads attempting entry notice the busy setting, and will simply 1140 * queue their new requests and exit immediately. Note that hwgroup->busy 1141 * remains set even when the driver is merely awaiting the next interrupt. 1142 * Thus, the meaning is "this hwgroup is busy processing a request". 1143 * 1144 * When processing of a request completes, the completing thread or IRQ-handler 1145 * will start the next request from the queue. If no more work remains, 1146 * the driver will clear the hwgroup->busy flag and exit. 1147 * 1148 * The ide_lock (spinlock) is used to protect all access to the 1149 * hwgroup->busy flag, but is otherwise not needed for most processing in 1150 * the driver. This makes the driver much more friendlier to shared IRQs 1151 * than previous designs, while remaining 100% (?) SMP safe and capable. 1152 */ 1153static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) 1154{ 1155 ide_drive_t *drive; 1156 ide_hwif_t *hwif; 1157 struct request *rq; 1158 ide_startstop_t startstop; 1159 int loops = 0; 1160 1161 /* for atari only: POSSIBLY BROKEN HERE(?) */ 1162 ide_get_lock(ide_intr, hwgroup); 1163 1164 /* caller must own ide_lock */ 1165 BUG_ON(!irqs_disabled()); 1166 1167 while (!hwgroup->busy) { 1168 hwgroup->busy = 1; 1169 drive = choose_drive(hwgroup); 1170 if (drive == NULL) { 1171 int sleeping = 0; 1172 unsigned long sleep = 0; /* shut up, gcc */ 1173 hwgroup->rq = NULL; 1174 drive = hwgroup->drive; 1175 do { 1176 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { 1177 sleeping = 1; 1178 sleep = drive->sleep; 1179 } 1180 } while ((drive = drive->next) != hwgroup->drive); 1181 if (sleeping) { 1182 /* 1183 * Take a short snooze, and then wake up this hwgroup again. 1184 * This gives other hwgroups on the same a chance to 1185 * play fairly with us, just in case there are big differences 1186 * in relative throughputs.. don't want to hog the cpu too much. 1187 */ 1188 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) 1189 sleep = jiffies + WAIT_MIN_SLEEP; 1190#if 1 1191 if (timer_pending(&hwgroup->timer)) 1192 printk(KERN_CRIT "ide_set_handler: timer already active\n"); 1193#endif 1194 /* so that ide_timer_expiry knows what to do */ 1195 hwgroup->sleeping = 1; 1196 hwgroup->req_gen_timer = hwgroup->req_gen; 1197 mod_timer(&hwgroup->timer, sleep); 1198 /* we purposely leave hwgroup->busy==1 1199 * while sleeping */ 1200 } else { 1201 /* Ugly, but how can we sleep for the lock 1202 * otherwise? perhaps from tq_disk? 1203 */ 1204 1205 /* for atari only */ 1206 ide_release_lock(); 1207 hwgroup->busy = 0; 1208 } 1209 1210 /* no more work for this hwgroup (for now) */ 1211 return; 1212 } 1213 again: 1214 hwif = HWIF(drive); 1215 if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) { 1216 /* 1217 * set nIEN for previous hwif, drives in the 1218 * quirk_list may not like intr setups/cleanups 1219 */ 1220 if (drive->quirk_list != 1) 1221 ide_set_irq(drive, 0); 1222 } 1223 hwgroup->hwif = hwif; 1224 hwgroup->drive = drive; 1225 drive->sleeping = 0; 1226 drive->service_start = jiffies; 1227 1228 if (blk_queue_plugged(drive->queue)) { 1229 printk(KERN_ERR "ide: huh? queue was plugged!\n"); 1230 break; 1231 } 1232 1233 /* 1234 * we know that the queue isn't empty, but this can happen 1235 * if the q->prep_rq_fn() decides to kill a request 1236 */ 1237 rq = elv_next_request(drive->queue); 1238 if (!rq) { 1239 hwgroup->busy = 0; 1240 break; 1241 } 1242 1243 /* 1244 * Sanity: don't accept a request that isn't a PM request 1245 * if we are currently power managed. This is very important as 1246 * blk_stop_queue() doesn't prevent the elv_next_request() 1247 * above to return us whatever is in the queue. Since we call 1248 * ide_do_request() ourselves, we end up taking requests while 1249 * the queue is blocked... 1250 * 1251 * We let requests forced at head of queue with ide-preempt 1252 * though. I hope that doesn't happen too much, hopefully not 1253 * unless the subdriver triggers such a thing in its own PM 1254 * state machine. 1255 * 1256 * We count how many times we loop here to make sure we service 1257 * all drives in the hwgroup without looping for ever 1258 */ 1259 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) { 1260 drive = drive->next ? drive->next : hwgroup->drive; 1261 if (loops++ < 4 && !blk_queue_plugged(drive->queue)) 1262 goto again; 1263 /* We clear busy, there should be no pending ATA command at this point. */ 1264 hwgroup->busy = 0; 1265 break; 1266 } 1267 1268 hwgroup->rq = rq; 1269 1270 /* 1271 * Some systems have trouble with IDE IRQs arriving while 1272 * the driver is still setting things up. So, here we disable 1273 * the IRQ used by this interface while the request is being started. 1274 * This may look bad at first, but pretty much the same thing 1275 * happens anyway when any interrupt comes in, IDE or otherwise 1276 * -- the kernel masks the IRQ while it is being handled. 1277 */ 1278 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1279 disable_irq_nosync(hwif->irq); 1280 spin_unlock(&ide_lock); 1281 local_irq_enable_in_hardirq(); 1282 /* allow other IRQs while we start this request */ 1283 startstop = start_request(drive, rq); 1284 spin_lock_irq(&ide_lock); 1285 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1286 enable_irq(hwif->irq); 1287 if (startstop == ide_stopped) 1288 hwgroup->busy = 0; 1289 } 1290} 1291 1292/* 1293 * Passes the stuff to ide_do_request 1294 */ 1295void do_ide_request(struct request_queue *q) 1296{ 1297 ide_drive_t *drive = q->queuedata; 1298 1299 ide_do_request(HWGROUP(drive), IDE_NO_IRQ); 1300} 1301 1302/* 1303 * un-busy the hwgroup etc, and clear any pending DMA status. we want to 1304 * retry the current request in pio mode instead of risking tossing it 1305 * all away 1306 */ 1307static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) 1308{ 1309 ide_hwif_t *hwif = HWIF(drive); 1310 struct request *rq; 1311 ide_startstop_t ret = ide_stopped; 1312 1313 /* 1314 * end current dma transaction 1315 */ 1316 1317 if (error < 0) { 1318 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); 1319 (void)HWIF(drive)->ide_dma_end(drive); 1320 ret = ide_error(drive, "dma timeout error", 1321 hwif->INB(IDE_STATUS_REG)); 1322 } else { 1323 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); 1324 hwif->dma_timeout(drive); 1325 } 1326 1327 /* 1328 * disable dma for now, but remember that we did so because of 1329 * a timeout -- we'll reenable after we finish this next request 1330 * (or rather the first chunk of it) in pio. 1331 */ 1332 drive->retry_pio++; 1333 drive->state = DMA_PIO_RETRY; 1334 ide_dma_off_quietly(drive); 1335 1336 /* 1337 * un-busy drive etc (hwgroup->busy is cleared on return) and 1338 * make sure request is sane 1339 */ 1340 rq = HWGROUP(drive)->rq; 1341 1342 if (!rq) 1343 goto out; 1344 1345 HWGROUP(drive)->rq = NULL; 1346 1347 rq->errors = 0; 1348 1349 if (!rq->bio) 1350 goto out; 1351 1352 rq->sector = rq->bio->bi_sector; 1353 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; 1354 rq->hard_cur_sectors = rq->current_nr_sectors; 1355 rq->buffer = bio_data(rq->bio); 1356out: 1357 return ret; 1358} 1359 1360/** 1361 * ide_timer_expiry - handle lack of an IDE interrupt 1362 * @data: timer callback magic (hwgroup) 1363 * 1364 * An IDE command has timed out before the expected drive return 1365 * occurred. At this point we attempt to clean up the current 1366 * mess. If the current handler includes an expiry handler then 1367 * we invoke the expiry handler, and providing it is happy the 1368 * work is done. If that fails we apply generic recovery rules 1369 * invoking the handler and checking the drive DMA status. We 1370 * have an excessively incestuous relationship with the DMA 1371 * logic that wants cleaning up. 1372 */ 1373 1374void ide_timer_expiry (unsigned long data) 1375{ 1376 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; 1377 ide_handler_t *handler; 1378 ide_expiry_t *expiry; 1379 unsigned long flags; 1380 unsigned long wait = -1; 1381 1382 spin_lock_irqsave(&ide_lock, flags); 1383 1384 if (((handler = hwgroup->handler) == NULL) || 1385 (hwgroup->req_gen != hwgroup->req_gen_timer)) { 1386 /* 1387 * Either a marginal timeout occurred 1388 * (got the interrupt just as timer expired), 1389 * or we were "sleeping" to give other devices a chance. 1390 * Either way, we don't really want to complain about anything. 1391 */ 1392 if (hwgroup->sleeping) { 1393 hwgroup->sleeping = 0; 1394 hwgroup->busy = 0; 1395 } 1396 } else { 1397 ide_drive_t *drive = hwgroup->drive; 1398 if (!drive) { 1399 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); 1400 hwgroup->handler = NULL; 1401 } else { 1402 ide_hwif_t *hwif; 1403 ide_startstop_t startstop = ide_stopped; 1404 if (!hwgroup->busy) { 1405 hwgroup->busy = 1; /* paranoia */ 1406 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); 1407 } 1408 if ((expiry = hwgroup->expiry) != NULL) { 1409 /* continue */ 1410 if ((wait = expiry(drive)) > 0) { 1411 /* reset timer */ 1412 hwgroup->timer.expires = jiffies + wait; 1413 hwgroup->req_gen_timer = hwgroup->req_gen; 1414 add_timer(&hwgroup->timer); 1415 spin_unlock_irqrestore(&ide_lock, flags); 1416 return; 1417 } 1418 } 1419 hwgroup->handler = NULL; 1420 /* 1421 * We need to simulate a real interrupt when invoking 1422 * the handler() function, which means we need to 1423 * globally mask the specific IRQ: 1424 */ 1425 spin_unlock(&ide_lock); 1426 hwif = HWIF(drive); 1427 /* disable_irq_nosync ?? */ 1428 disable_irq(hwif->irq); 1429 /* local CPU only, 1430 * as if we were handling an interrupt */ 1431 local_irq_disable(); 1432 if (hwgroup->polling) { 1433 startstop = handler(drive); 1434 } else if (drive_is_ready(drive)) { 1435 if (drive->waiting_for_dma) 1436 hwgroup->hwif->dma_lost_irq(drive); 1437 (void)ide_ack_intr(hwif); 1438 printk(KERN_WARNING "%s: lost interrupt\n", drive->name); 1439 startstop = handler(drive); 1440 } else { 1441 if (drive->waiting_for_dma) { 1442 startstop = ide_dma_timeout_retry(drive, wait); 1443 } else 1444 startstop = 1445 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG)); 1446 } 1447 drive->service_time = jiffies - drive->service_start; 1448 spin_lock_irq(&ide_lock); 1449 enable_irq(hwif->irq); 1450 if (startstop == ide_stopped) 1451 hwgroup->busy = 0; 1452 } 1453 } 1454 ide_do_request(hwgroup, IDE_NO_IRQ); 1455 spin_unlock_irqrestore(&ide_lock, flags); 1456} 1457 1458/** 1459 * unexpected_intr - handle an unexpected IDE interrupt 1460 * @irq: interrupt line 1461 * @hwgroup: hwgroup being processed 1462 * 1463 * There's nothing really useful we can do with an unexpected interrupt, 1464 * other than reading the status register (to clear it), and logging it. 1465 * There should be no way that an irq can happen before we're ready for it, 1466 * so we needn't worry much about losing an "important" interrupt here. 1467 * 1468 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever 1469 * the drive enters "idle", "standby", or "sleep" mode, so if the status 1470 * looks "good", we just ignore the interrupt completely. 1471 * 1472 * This routine assumes __cli() is in effect when called. 1473 * 1474 * If an unexpected interrupt happens on irq15 while we are handling irq14 1475 * and if the two interfaces are "serialized" (CMD640), then it looks like 1476 * we could screw up by interfering with a new request being set up for 1477 * irq15. 1478 * 1479 * In reality, this is a non-issue. The new command is not sent unless 1480 * the drive is ready to accept one, in which case we know the drive is 1481 * not trying to interrupt us. And ide_set_handler() is always invoked 1482 * before completing the issuance of any new drive command, so we will not 1483 * be accidentally invoked as a result of any valid command completion 1484 * interrupt. 1485 * 1486 * Note that we must walk the entire hwgroup here. We know which hwif 1487 * is doing the current command, but we don't know which hwif burped 1488 * mysteriously. 1489 */ 1490 1491static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) 1492{ 1493 u8 stat; 1494 ide_hwif_t *hwif = hwgroup->hwif; 1495 1496 /* 1497 * handle the unexpected interrupt 1498 */ 1499 do { 1500 if (hwif->irq == irq) { 1501 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1502 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { 1503 /* Try to not flood the console with msgs */ 1504 static unsigned long last_msgtime, count; 1505 ++count; 1506 if (time_after(jiffies, last_msgtime + HZ)) { 1507 last_msgtime = jiffies; 1508 printk(KERN_ERR "%s%s: unexpected interrupt, " 1509 "status=0x%02x, count=%ld\n", 1510 hwif->name, 1511 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); 1512 } 1513 } 1514 } 1515 } while ((hwif = hwif->next) != hwgroup->hwif); 1516} 1517 1518/** 1519 * ide_intr - default IDE interrupt handler 1520 * @irq: interrupt number 1521 * @dev_id: hwif group 1522 * @regs: unused weirdness from the kernel irq layer 1523 * 1524 * This is the default IRQ handler for the IDE layer. You should 1525 * not need to override it. If you do be aware it is subtle in 1526 * places 1527 * 1528 * hwgroup->hwif is the interface in the group currently performing 1529 * a command. hwgroup->drive is the drive and hwgroup->handler is 1530 * the IRQ handler to call. As we issue a command the handlers 1531 * step through multiple states, reassigning the handler to the 1532 * next step in the process. Unlike a smart SCSI controller IDE 1533 * expects the main processor to sequence the various transfer 1534 * stages. We also manage a poll timer to catch up with most 1535 * timeout situations. There are still a few where the handlers 1536 * don't ever decide to give up. 1537 * 1538 * The handler eventually returns ide_stopped to indicate the 1539 * request completed. At this point we issue the next request 1540 * on the hwgroup and the process begins again. 1541 */ 1542 1543irqreturn_t ide_intr (int irq, void *dev_id) 1544{ 1545 unsigned long flags; 1546 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; 1547 ide_hwif_t *hwif; 1548 ide_drive_t *drive; 1549 ide_handler_t *handler; 1550 ide_startstop_t startstop; 1551 1552 spin_lock_irqsave(&ide_lock, flags); 1553 hwif = hwgroup->hwif; 1554 1555 if (!ide_ack_intr(hwif)) { 1556 spin_unlock_irqrestore(&ide_lock, flags); 1557 return IRQ_NONE; 1558 } 1559 1560 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { 1561 /* 1562 * Not expecting an interrupt from this drive. 1563 * That means this could be: 1564 * (1) an interrupt from another PCI device 1565 * sharing the same PCI INT# as us. 1566 * or (2) a drive just entered sleep or standby mode, 1567 * and is interrupting to let us know. 1568 * or (3) a spurious interrupt of unknown origin. 1569 * 1570 * For PCI, we cannot tell the difference, 1571 * so in that case we just ignore it and hope it goes away. 1572 * 1573 * FIXME: unexpected_intr should be hwif-> then we can 1574 * remove all the ifdef PCI crap 1575 */ 1576#ifdef CONFIG_BLK_DEV_IDEPCI 1577 if (hwif->pci_dev && !hwif->pci_dev->vendor) 1578#endif /* CONFIG_BLK_DEV_IDEPCI */ 1579 { 1580 /* 1581 * Probably not a shared PCI interrupt, 1582 * so we can safely try to do something about it: 1583 */ 1584 unexpected_intr(irq, hwgroup); 1585#ifdef CONFIG_BLK_DEV_IDEPCI 1586 } else { 1587 /* 1588 * Whack the status register, just in case 1589 * we have a leftover pending IRQ. 1590 */ 1591 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1592#endif /* CONFIG_BLK_DEV_IDEPCI */ 1593 } 1594 spin_unlock_irqrestore(&ide_lock, flags); 1595 return IRQ_NONE; 1596 } 1597 drive = hwgroup->drive; 1598 if (!drive) { 1599 /* 1600 * This should NEVER happen, and there isn't much 1601 * we could do about it here. 1602 * 1603 * [Note - this can occur if the drive is hot unplugged] 1604 */ 1605 spin_unlock_irqrestore(&ide_lock, flags); 1606 return IRQ_HANDLED; 1607 } 1608 if (!drive_is_ready(drive)) { 1609 /* 1610 * This happens regularly when we share a PCI IRQ with 1611 * another device. Unfortunately, it can also happen 1612 * with some buggy drives that trigger the IRQ before 1613 * their status register is up to date. Hopefully we have 1614 * enough advance overhead that the latter isn't a problem. 1615 */ 1616 spin_unlock_irqrestore(&ide_lock, flags); 1617 return IRQ_NONE; 1618 } 1619 if (!hwgroup->busy) { 1620 hwgroup->busy = 1; /* paranoia */ 1621 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); 1622 } 1623 hwgroup->handler = NULL; 1624 hwgroup->req_gen++; 1625 del_timer(&hwgroup->timer); 1626 spin_unlock(&ide_lock); 1627 1628 /* Some controllers might set DMA INTR no matter DMA or PIO; 1629 * bmdma status might need to be cleared even for 1630 * PIO interrupts to prevent spurious/lost irq. 1631 */ 1632 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma)) 1633 /* ide_dma_end() needs bmdma status for error checking. 1634 * So, skip clearing bmdma status here and leave it 1635 * to ide_dma_end() if this is dma interrupt. 1636 */ 1637 hwif->ide_dma_clear_irq(drive); 1638 1639 if (drive->unmask) 1640 local_irq_enable_in_hardirq(); 1641 /* service this interrupt, may set handler for next interrupt */ 1642 startstop = handler(drive); 1643 spin_lock_irq(&ide_lock); 1644 1645 /* 1646 * Note that handler() may have set things up for another 1647 * interrupt to occur soon, but it cannot happen until 1648 * we exit from this routine, because it will be the 1649 * same irq as is currently being serviced here, and Linux 1650 * won't allow another of the same (on any CPU) until we return. 1651 */ 1652 drive->service_time = jiffies - drive->service_start; 1653 if (startstop == ide_stopped) { 1654 if (hwgroup->handler == NULL) { /* paranoia */ 1655 hwgroup->busy = 0; 1656 ide_do_request(hwgroup, hwif->irq); 1657 } else { 1658 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " 1659 "on exit\n", drive->name); 1660 } 1661 } 1662 spin_unlock_irqrestore(&ide_lock, flags); 1663 return IRQ_HANDLED; 1664} 1665 1666/** 1667 * ide_init_drive_cmd - initialize a drive command request 1668 * @rq: request object 1669 * 1670 * Initialize a request before we fill it in and send it down to 1671 * ide_do_drive_cmd. Commands must be set up by this function. Right 1672 * now it doesn't do a lot, but if that changes abusers will have a 1673 * nasty surprise. 1674 */ 1675 1676void ide_init_drive_cmd (struct request *rq) 1677{ 1678 memset(rq, 0, sizeof(*rq)); 1679 rq->cmd_type = REQ_TYPE_ATA_CMD; 1680 rq->ref_count = 1; 1681} 1682 1683EXPORT_SYMBOL(ide_init_drive_cmd); 1684 1685/** 1686 * ide_do_drive_cmd - issue IDE special command 1687 * @drive: device to issue command 1688 * @rq: request to issue 1689 * @action: action for processing 1690 * 1691 * This function issues a special IDE device request 1692 * onto the request queue. 1693 * 1694 * If action is ide_wait, then the rq is queued at the end of the 1695 * request queue, and the function sleeps until it has been processed. 1696 * This is for use when invoked from an ioctl handler. 1697 * 1698 * If action is ide_preempt, then the rq is queued at the head of 1699 * the request queue, displacing the currently-being-processed 1700 * request and this function returns immediately without waiting 1701 * for the new rq to be completed. This is VERY DANGEROUS, and is 1702 * intended for careful use by the ATAPI tape/cdrom driver code. 1703 * 1704 * If action is ide_end, then the rq is queued at the end of the 1705 * request queue, and the function returns immediately without waiting 1706 * for the new rq to be completed. This is again intended for careful 1707 * use by the ATAPI tape/cdrom driver code. 1708 */ 1709 1710int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) 1711{ 1712 unsigned long flags; 1713 ide_hwgroup_t *hwgroup = HWGROUP(drive); 1714 DECLARE_COMPLETION_ONSTACK(wait); 1715 int where = ELEVATOR_INSERT_BACK, err; 1716 int must_wait = (action == ide_wait || action == ide_head_wait); 1717 1718 rq->errors = 0; 1719 1720 /* 1721 * we need to hold an extra reference to request for safe inspection 1722 * after completion 1723 */ 1724 if (must_wait) { 1725 rq->ref_count++; 1726 rq->end_io_data = &wait; 1727 rq->end_io = blk_end_sync_rq; 1728 } 1729 1730 spin_lock_irqsave(&ide_lock, flags); 1731 if (action == ide_preempt) 1732 hwgroup->rq = NULL; 1733 if (action == ide_preempt || action == ide_head_wait) { 1734 where = ELEVATOR_INSERT_FRONT; 1735 rq->cmd_flags |= REQ_PREEMPT; 1736 } 1737 __elv_add_request(drive->queue, rq, where, 0); 1738 ide_do_request(hwgroup, IDE_NO_IRQ); 1739 spin_unlock_irqrestore(&ide_lock, flags); 1740 1741 err = 0; 1742 if (must_wait) { 1743 wait_for_completion(&wait); 1744 if (rq->errors) 1745 err = -EIO; 1746 1747 blk_put_request(rq); 1748 } 1749 1750 return err; 1751} 1752 1753EXPORT_SYMBOL(ide_do_drive_cmd); 1754 1755void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma) 1756{ 1757 ide_task_t task; 1758 1759 memset(&task, 0, sizeof(task)); 1760 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM | 1761 IDE_TFLAG_OUT_FEATURE | tf_flags; 1762 task.tf.feature = dma; /* Use PIO/DMA */ 1763 task.tf.lbam = bcount & 0xff; 1764 task.tf.lbah = (bcount >> 8) & 0xff; 1765 1766 ide_tf_load(drive, &task); 1767} 1768 1769EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load); 1770