ide-io.c revision 8ffdc6550c47f75ca4e6c9f30a2a89063e035cf2
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/config.h> 28#include <linux/module.h> 29#include <linux/types.h> 30#include <linux/string.h> 31#include <linux/kernel.h> 32#include <linux/timer.h> 33#include <linux/mm.h> 34#include <linux/interrupt.h> 35#include <linux/major.h> 36#include <linux/errno.h> 37#include <linux/genhd.h> 38#include <linux/blkpg.h> 39#include <linux/slab.h> 40#include <linux/init.h> 41#include <linux/pci.h> 42#include <linux/delay.h> 43#include <linux/ide.h> 44#include <linux/completion.h> 45#include <linux/reboot.h> 46#include <linux/cdrom.h> 47#include <linux/seq_file.h> 48#include <linux/device.h> 49#include <linux/kmod.h> 50#include <linux/scatterlist.h> 51 52#include <asm/byteorder.h> 53#include <asm/irq.h> 54#include <asm/uaccess.h> 55#include <asm/io.h> 56#include <asm/bitops.h> 57 58int __ide_end_request(ide_drive_t *drive, struct request *rq, int uptodate, 59 int nr_sectors) 60{ 61 int ret = 1; 62 63 BUG_ON(!(rq->flags & REQ_STARTED)); 64 65 /* 66 * if failfast is set on a request, override number of sectors and 67 * complete the whole request right now 68 */ 69 if (blk_noretry_request(rq) && end_io_error(uptodate)) 70 nr_sectors = rq->hard_nr_sectors; 71 72 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors) 73 rq->errors = -EIO; 74 75 /* 76 * decide whether to reenable DMA -- 3 is a random magic for now, 77 * if we DMA timeout more than 3 times, just stay in PIO 78 */ 79 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) { 80 drive->state = 0; 81 HWGROUP(drive)->hwif->ide_dma_on(drive); 82 } 83 84 if (!end_that_request_first(rq, uptodate, nr_sectors)) { 85 add_disk_randomness(rq->rq_disk); 86 87 if (blk_rq_tagged(rq)) 88 blk_queue_end_tag(drive->queue, rq); 89 90 blkdev_dequeue_request(rq); 91 HWGROUP(drive)->rq = NULL; 92 end_that_request_last(rq, uptodate); 93 ret = 0; 94 } 95 return ret; 96} 97EXPORT_SYMBOL(__ide_end_request); 98 99/** 100 * ide_end_request - complete an IDE I/O 101 * @drive: IDE device for the I/O 102 * @uptodate: 103 * @nr_sectors: number of sectors completed 104 * 105 * This is our end_request wrapper function. We complete the I/O 106 * update random number input and dequeue the request, which if 107 * it was tagged may be out of order. 108 */ 109 110int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors) 111{ 112 struct request *rq; 113 unsigned long flags; 114 int ret = 1; 115 116 spin_lock_irqsave(&ide_lock, flags); 117 rq = HWGROUP(drive)->rq; 118 119 if (!nr_sectors) 120 nr_sectors = rq->hard_cur_sectors; 121 122 if (blk_complete_barrier_rq_locked(drive->queue, rq, nr_sectors)) 123 ret = rq->nr_sectors != 0; 124 else 125 ret = __ide_end_request(drive, rq, uptodate, nr_sectors); 126 127 spin_unlock_irqrestore(&ide_lock, flags); 128 return ret; 129} 130EXPORT_SYMBOL(ide_end_request); 131 132/* 133 * Power Management state machine. This one is rather trivial for now, 134 * we should probably add more, like switching back to PIO on suspend 135 * to help some BIOSes, re-do the door locking on resume, etc... 136 */ 137 138enum { 139 ide_pm_flush_cache = ide_pm_state_start_suspend, 140 idedisk_pm_standby, 141 142 idedisk_pm_idle = ide_pm_state_start_resume, 143 ide_pm_restore_dma, 144}; 145 146static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error) 147{ 148 if (drive->media != ide_disk) 149 return; 150 151 switch (rq->pm->pm_step) { 152 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */ 153 if (rq->pm->pm_state == PM_EVENT_FREEZE) 154 rq->pm->pm_step = ide_pm_state_completed; 155 else 156 rq->pm->pm_step = idedisk_pm_standby; 157 break; 158 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */ 159 rq->pm->pm_step = ide_pm_state_completed; 160 break; 161 case idedisk_pm_idle: /* Resume step 1 (idle) complete */ 162 rq->pm->pm_step = ide_pm_restore_dma; 163 break; 164 } 165} 166 167static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq) 168{ 169 ide_task_t *args = rq->special; 170 171 memset(args, 0, sizeof(*args)); 172 173 if (drive->media != ide_disk) { 174 /* skip idedisk_pm_idle for ATAPI devices */ 175 if (rq->pm->pm_step == idedisk_pm_idle) 176 rq->pm->pm_step = ide_pm_restore_dma; 177 } 178 179 switch (rq->pm->pm_step) { 180 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */ 181 if (drive->media != ide_disk) 182 break; 183 /* Not supported? Switch to next step now. */ 184 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) { 185 ide_complete_power_step(drive, rq, 0, 0); 186 return ide_stopped; 187 } 188 if (ide_id_has_flush_cache_ext(drive->id)) 189 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE_EXT; 190 else 191 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE; 192 args->command_type = IDE_DRIVE_TASK_NO_DATA; 193 args->handler = &task_no_data_intr; 194 return do_rw_taskfile(drive, args); 195 196 case idedisk_pm_standby: /* Suspend step 2 (standby) */ 197 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_STANDBYNOW1; 198 args->command_type = IDE_DRIVE_TASK_NO_DATA; 199 args->handler = &task_no_data_intr; 200 return do_rw_taskfile(drive, args); 201 202 case idedisk_pm_idle: /* Resume step 1 (idle) */ 203 args->tfRegister[IDE_COMMAND_OFFSET] = WIN_IDLEIMMEDIATE; 204 args->command_type = IDE_DRIVE_TASK_NO_DATA; 205 args->handler = task_no_data_intr; 206 return do_rw_taskfile(drive, args); 207 208 case ide_pm_restore_dma: /* Resume step 2 (restore DMA) */ 209 /* 210 * Right now, all we do is call hwif->ide_dma_check(drive), 211 * we could be smarter and check for current xfer_speed 212 * in struct drive etc... 213 */ 214 if ((drive->id->capability & 1) == 0) 215 break; 216 if (drive->hwif->ide_dma_check == NULL) 217 break; 218 drive->hwif->ide_dma_check(drive); 219 break; 220 } 221 rq->pm->pm_step = ide_pm_state_completed; 222 return ide_stopped; 223} 224 225/** 226 * ide_complete_pm_request - end the current Power Management request 227 * @drive: target drive 228 * @rq: request 229 * 230 * This function cleans up the current PM request and stops the queue 231 * if necessary. 232 */ 233static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq) 234{ 235 unsigned long flags; 236 237#ifdef DEBUG_PM 238 printk("%s: completing PM request, %s\n", drive->name, 239 blk_pm_suspend_request(rq) ? "suspend" : "resume"); 240#endif 241 spin_lock_irqsave(&ide_lock, flags); 242 if (blk_pm_suspend_request(rq)) { 243 blk_stop_queue(drive->queue); 244 } else { 245 drive->blocked = 0; 246 blk_start_queue(drive->queue); 247 } 248 blkdev_dequeue_request(rq); 249 HWGROUP(drive)->rq = NULL; 250 end_that_request_last(rq, 1); 251 spin_unlock_irqrestore(&ide_lock, flags); 252} 253 254/* 255 * FIXME: probably move this somewhere else, name is bad too :) 256 */ 257u64 ide_get_error_location(ide_drive_t *drive, char *args) 258{ 259 u32 high, low; 260 u8 hcyl, lcyl, sect; 261 u64 sector; 262 263 high = 0; 264 hcyl = args[5]; 265 lcyl = args[4]; 266 sect = args[3]; 267 268 if (ide_id_has_flush_cache_ext(drive->id)) { 269 low = (hcyl << 16) | (lcyl << 8) | sect; 270 HWIF(drive)->OUTB(drive->ctl|0x80, IDE_CONTROL_REG); 271 high = ide_read_24(drive); 272 } else { 273 u8 cur = HWIF(drive)->INB(IDE_SELECT_REG); 274 if (cur & 0x40) { 275 high = cur & 0xf; 276 low = (hcyl << 16) | (lcyl << 8) | sect; 277 } else { 278 low = hcyl * drive->head * drive->sect; 279 low += lcyl * drive->sect; 280 low += sect - 1; 281 } 282 } 283 284 sector = ((u64) high << 24) | low; 285 return sector; 286} 287EXPORT_SYMBOL(ide_get_error_location); 288 289/** 290 * ide_end_drive_cmd - end an explicit drive command 291 * @drive: command 292 * @stat: status bits 293 * @err: error bits 294 * 295 * Clean up after success/failure of an explicit drive command. 296 * These get thrown onto the queue so they are synchronized with 297 * real I/O operations on the drive. 298 * 299 * In LBA48 mode we have to read the register set twice to get 300 * all the extra information out. 301 */ 302 303void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) 304{ 305 ide_hwif_t *hwif = HWIF(drive); 306 unsigned long flags; 307 struct request *rq; 308 309 spin_lock_irqsave(&ide_lock, flags); 310 rq = HWGROUP(drive)->rq; 311 spin_unlock_irqrestore(&ide_lock, flags); 312 313 if (rq->flags & REQ_DRIVE_CMD) { 314 u8 *args = (u8 *) rq->buffer; 315 if (rq->errors == 0) 316 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 317 318 if (args) { 319 args[0] = stat; 320 args[1] = err; 321 args[2] = hwif->INB(IDE_NSECTOR_REG); 322 } 323 } else if (rq->flags & REQ_DRIVE_TASK) { 324 u8 *args = (u8 *) rq->buffer; 325 if (rq->errors == 0) 326 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 327 328 if (args) { 329 args[0] = stat; 330 args[1] = err; 331 args[2] = hwif->INB(IDE_NSECTOR_REG); 332 args[3] = hwif->INB(IDE_SECTOR_REG); 333 args[4] = hwif->INB(IDE_LCYL_REG); 334 args[5] = hwif->INB(IDE_HCYL_REG); 335 args[6] = hwif->INB(IDE_SELECT_REG); 336 } 337 } else if (rq->flags & REQ_DRIVE_TASKFILE) { 338 ide_task_t *args = (ide_task_t *) rq->special; 339 if (rq->errors == 0) 340 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 341 342 if (args) { 343 if (args->tf_in_flags.b.data) { 344 u16 data = hwif->INW(IDE_DATA_REG); 345 args->tfRegister[IDE_DATA_OFFSET] = (data) & 0xFF; 346 args->hobRegister[IDE_DATA_OFFSET] = (data >> 8) & 0xFF; 347 } 348 args->tfRegister[IDE_ERROR_OFFSET] = err; 349 /* be sure we're looking at the low order bits */ 350 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG); 351 args->tfRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG); 352 args->tfRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG); 353 args->tfRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG); 354 args->tfRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG); 355 args->tfRegister[IDE_SELECT_OFFSET] = hwif->INB(IDE_SELECT_REG); 356 args->tfRegister[IDE_STATUS_OFFSET] = stat; 357 358 if (drive->addressing == 1) { 359 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG); 360 args->hobRegister[IDE_FEATURE_OFFSET] = hwif->INB(IDE_FEATURE_REG); 361 args->hobRegister[IDE_NSECTOR_OFFSET] = hwif->INB(IDE_NSECTOR_REG); 362 args->hobRegister[IDE_SECTOR_OFFSET] = hwif->INB(IDE_SECTOR_REG); 363 args->hobRegister[IDE_LCYL_OFFSET] = hwif->INB(IDE_LCYL_REG); 364 args->hobRegister[IDE_HCYL_OFFSET] = hwif->INB(IDE_HCYL_REG); 365 } 366 } 367 } else if (blk_pm_request(rq)) { 368#ifdef DEBUG_PM 369 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n", 370 drive->name, rq->pm->pm_step, stat, err); 371#endif 372 ide_complete_power_step(drive, rq, stat, err); 373 if (rq->pm->pm_step == ide_pm_state_completed) 374 ide_complete_pm_request(drive, rq); 375 return; 376 } 377 378 spin_lock_irqsave(&ide_lock, flags); 379 blkdev_dequeue_request(rq); 380 HWGROUP(drive)->rq = NULL; 381 rq->errors = err; 382 end_that_request_last(rq, !rq->errors); 383 spin_unlock_irqrestore(&ide_lock, flags); 384} 385 386EXPORT_SYMBOL(ide_end_drive_cmd); 387 388/** 389 * try_to_flush_leftover_data - flush junk 390 * @drive: drive to flush 391 * 392 * try_to_flush_leftover_data() is invoked in response to a drive 393 * unexpectedly having its DRQ_STAT bit set. As an alternative to 394 * resetting the drive, this routine tries to clear the condition 395 * by read a sector's worth of data from the drive. Of course, 396 * this may not help if the drive is *waiting* for data from *us*. 397 */ 398static void try_to_flush_leftover_data (ide_drive_t *drive) 399{ 400 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS; 401 402 if (drive->media != ide_disk) 403 return; 404 while (i > 0) { 405 u32 buffer[16]; 406 u32 wcount = (i > 16) ? 16 : i; 407 408 i -= wcount; 409 HWIF(drive)->ata_input_data(drive, buffer, wcount); 410 } 411} 412 413static void ide_kill_rq(ide_drive_t *drive, struct request *rq) 414{ 415 if (rq->rq_disk) { 416 ide_driver_t *drv; 417 418 drv = *(ide_driver_t **)rq->rq_disk->private_data; 419 drv->end_request(drive, 0, 0); 420 } else 421 ide_end_request(drive, 0, 0); 422} 423 424static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 425{ 426 ide_hwif_t *hwif = drive->hwif; 427 428 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 429 /* other bits are useless when BUSY */ 430 rq->errors |= ERROR_RESET; 431 } else if (stat & ERR_STAT) { 432 /* err has different meaning on cdrom and tape */ 433 if (err == ABRT_ERR) { 434 if (drive->select.b.lba && 435 /* some newer drives don't support WIN_SPECIFY */ 436 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY) 437 return ide_stopped; 438 } else if ((err & BAD_CRC) == BAD_CRC) { 439 /* UDMA crc error, just retry the operation */ 440 drive->crc_count++; 441 } else if (err & (BBD_ERR | ECC_ERR)) { 442 /* retries won't help these */ 443 rq->errors = ERROR_MAX; 444 } else if (err & TRK0_ERR) { 445 /* help it find track zero */ 446 rq->errors |= ERROR_RECAL; 447 } 448 } 449 450 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ) 451 try_to_flush_leftover_data(drive); 452 453 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 454 /* force an abort */ 455 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 456 457 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) 458 ide_kill_rq(drive, rq); 459 else { 460 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 461 ++rq->errors; 462 return ide_do_reset(drive); 463 } 464 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) 465 drive->special.b.recalibrate = 1; 466 ++rq->errors; 467 } 468 return ide_stopped; 469} 470 471static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 472{ 473 ide_hwif_t *hwif = drive->hwif; 474 475 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 476 /* other bits are useless when BUSY */ 477 rq->errors |= ERROR_RESET; 478 } else { 479 /* add decoding error stuff */ 480 } 481 482 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 483 /* force an abort */ 484 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 485 486 if (rq->errors >= ERROR_MAX) { 487 ide_kill_rq(drive, rq); 488 } else { 489 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 490 ++rq->errors; 491 return ide_do_reset(drive); 492 } 493 ++rq->errors; 494 } 495 496 return ide_stopped; 497} 498 499ide_startstop_t 500__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 501{ 502 if (drive->media == ide_disk) 503 return ide_ata_error(drive, rq, stat, err); 504 return ide_atapi_error(drive, rq, stat, err); 505} 506 507EXPORT_SYMBOL_GPL(__ide_error); 508 509/** 510 * ide_error - handle an error on the IDE 511 * @drive: drive the error occurred on 512 * @msg: message to report 513 * @stat: status bits 514 * 515 * ide_error() takes action based on the error returned by the drive. 516 * For normal I/O that may well include retries. We deal with 517 * both new-style (taskfile) and old style command handling here. 518 * In the case of taskfile command handling there is work left to 519 * do 520 */ 521 522ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) 523{ 524 struct request *rq; 525 u8 err; 526 527 err = ide_dump_status(drive, msg, stat); 528 529 if ((rq = HWGROUP(drive)->rq) == NULL) 530 return ide_stopped; 531 532 /* retry only "normal" I/O: */ 533 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) { 534 rq->errors = 1; 535 ide_end_drive_cmd(drive, stat, err); 536 return ide_stopped; 537 } 538 539 if (rq->rq_disk) { 540 ide_driver_t *drv; 541 542 drv = *(ide_driver_t **)rq->rq_disk->private_data; 543 return drv->error(drive, rq, stat, err); 544 } else 545 return __ide_error(drive, rq, stat, err); 546} 547 548EXPORT_SYMBOL_GPL(ide_error); 549 550ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) 551{ 552 if (drive->media != ide_disk) 553 rq->errors |= ERROR_RESET; 554 555 ide_kill_rq(drive, rq); 556 557 return ide_stopped; 558} 559 560EXPORT_SYMBOL_GPL(__ide_abort); 561 562/** 563 * ide_abort - abort pending IDE operations 564 * @drive: drive the error occurred on 565 * @msg: message to report 566 * 567 * ide_abort kills and cleans up when we are about to do a 568 * host initiated reset on active commands. Longer term we 569 * want handlers to have sensible abort handling themselves 570 * 571 * This differs fundamentally from ide_error because in 572 * this case the command is doing just fine when we 573 * blow it away. 574 */ 575 576ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) 577{ 578 struct request *rq; 579 580 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) 581 return ide_stopped; 582 583 /* retry only "normal" I/O: */ 584 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) { 585 rq->errors = 1; 586 ide_end_drive_cmd(drive, BUSY_STAT, 0); 587 return ide_stopped; 588 } 589 590 if (rq->rq_disk) { 591 ide_driver_t *drv; 592 593 drv = *(ide_driver_t **)rq->rq_disk->private_data; 594 return drv->abort(drive, rq); 595 } else 596 return __ide_abort(drive, rq); 597} 598 599/** 600 * ide_cmd - issue a simple drive command 601 * @drive: drive the command is for 602 * @cmd: command byte 603 * @nsect: sector byte 604 * @handler: handler for the command completion 605 * 606 * Issue a simple drive command with interrupts. 607 * The drive must be selected beforehand. 608 */ 609 610static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect, 611 ide_handler_t *handler) 612{ 613 ide_hwif_t *hwif = HWIF(drive); 614 if (IDE_CONTROL_REG) 615 hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */ 616 SELECT_MASK(drive,0); 617 hwif->OUTB(nsect,IDE_NSECTOR_REG); 618 ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL); 619} 620 621/** 622 * drive_cmd_intr - drive command completion interrupt 623 * @drive: drive the completion interrupt occurred on 624 * 625 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD. 626 * We do any necessary data reading and then wait for the drive to 627 * go non busy. At that point we may read the error data and complete 628 * the request 629 */ 630 631static ide_startstop_t drive_cmd_intr (ide_drive_t *drive) 632{ 633 struct request *rq = HWGROUP(drive)->rq; 634 ide_hwif_t *hwif = HWIF(drive); 635 u8 *args = (u8 *) rq->buffer; 636 u8 stat = hwif->INB(IDE_STATUS_REG); 637 int retries = 10; 638 639 local_irq_enable(); 640 if ((stat & DRQ_STAT) && args && args[3]) { 641 u8 io_32bit = drive->io_32bit; 642 drive->io_32bit = 0; 643 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS); 644 drive->io_32bit = io_32bit; 645 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--) 646 udelay(100); 647 } 648 649 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) 650 return ide_error(drive, "drive_cmd", stat); 651 /* calls ide_end_drive_cmd */ 652 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG)); 653 return ide_stopped; 654} 655 656static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task) 657{ 658 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect; 659 task->tfRegister[IDE_SECTOR_OFFSET] = drive->sect; 660 task->tfRegister[IDE_LCYL_OFFSET] = drive->cyl; 661 task->tfRegister[IDE_HCYL_OFFSET] = drive->cyl>>8; 662 task->tfRegister[IDE_SELECT_OFFSET] = ((drive->head-1)|drive->select.all)&0xBF; 663 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY; 664 665 task->handler = &set_geometry_intr; 666} 667 668static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task) 669{ 670 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect; 671 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE; 672 673 task->handler = &recal_intr; 674} 675 676static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task) 677{ 678 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req; 679 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT; 680 681 task->handler = &set_multmode_intr; 682} 683 684static ide_startstop_t ide_disk_special(ide_drive_t *drive) 685{ 686 special_t *s = &drive->special; 687 ide_task_t args; 688 689 memset(&args, 0, sizeof(ide_task_t)); 690 args.command_type = IDE_DRIVE_TASK_NO_DATA; 691 692 if (s->b.set_geometry) { 693 s->b.set_geometry = 0; 694 ide_init_specify_cmd(drive, &args); 695 } else if (s->b.recalibrate) { 696 s->b.recalibrate = 0; 697 ide_init_restore_cmd(drive, &args); 698 } else if (s->b.set_multmode) { 699 s->b.set_multmode = 0; 700 if (drive->mult_req > drive->id->max_multsect) 701 drive->mult_req = drive->id->max_multsect; 702 ide_init_setmult_cmd(drive, &args); 703 } else if (s->all) { 704 int special = s->all; 705 s->all = 0; 706 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); 707 return ide_stopped; 708 } 709 710 do_rw_taskfile(drive, &args); 711 712 return ide_started; 713} 714 715/** 716 * do_special - issue some special commands 717 * @drive: drive the command is for 718 * 719 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT 720 * commands to a drive. It used to do much more, but has been scaled 721 * back. 722 */ 723 724static ide_startstop_t do_special (ide_drive_t *drive) 725{ 726 special_t *s = &drive->special; 727 728#ifdef DEBUG 729 printk("%s: do_special: 0x%02x\n", drive->name, s->all); 730#endif 731 if (s->b.set_tune) { 732 s->b.set_tune = 0; 733 if (HWIF(drive)->tuneproc != NULL) 734 HWIF(drive)->tuneproc(drive, drive->tune_req); 735 return ide_stopped; 736 } else { 737 if (drive->media == ide_disk) 738 return ide_disk_special(drive); 739 740 s->all = 0; 741 drive->mult_req = 0; 742 return ide_stopped; 743 } 744} 745 746void ide_map_sg(ide_drive_t *drive, struct request *rq) 747{ 748 ide_hwif_t *hwif = drive->hwif; 749 struct scatterlist *sg = hwif->sg_table; 750 751 if (hwif->sg_mapped) /* needed by ide-scsi */ 752 return; 753 754 if ((rq->flags & REQ_DRIVE_TASKFILE) == 0) { 755 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); 756 } else { 757 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); 758 hwif->sg_nents = 1; 759 } 760} 761 762EXPORT_SYMBOL_GPL(ide_map_sg); 763 764void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) 765{ 766 ide_hwif_t *hwif = drive->hwif; 767 768 hwif->nsect = hwif->nleft = rq->nr_sectors; 769 hwif->cursg = hwif->cursg_ofs = 0; 770} 771 772EXPORT_SYMBOL_GPL(ide_init_sg_cmd); 773 774/** 775 * execute_drive_command - issue special drive command 776 * @drive: the drive to issue the command on 777 * @rq: the request structure holding the command 778 * 779 * execute_drive_cmd() issues a special drive command, usually 780 * initiated by ioctl() from the external hdparm program. The 781 * command can be a drive command, drive task or taskfile 782 * operation. Weirdly you can call it with NULL to wait for 783 * all commands to finish. Don't do this as that is due to change 784 */ 785 786static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, 787 struct request *rq) 788{ 789 ide_hwif_t *hwif = HWIF(drive); 790 if (rq->flags & REQ_DRIVE_TASKFILE) { 791 ide_task_t *args = rq->special; 792 793 if (!args) 794 goto done; 795 796 hwif->data_phase = args->data_phase; 797 798 switch (hwif->data_phase) { 799 case TASKFILE_MULTI_OUT: 800 case TASKFILE_OUT: 801 case TASKFILE_MULTI_IN: 802 case TASKFILE_IN: 803 ide_init_sg_cmd(drive, rq); 804 ide_map_sg(drive, rq); 805 default: 806 break; 807 } 808 809 if (args->tf_out_flags.all != 0) 810 return flagged_taskfile(drive, args); 811 return do_rw_taskfile(drive, args); 812 } else if (rq->flags & REQ_DRIVE_TASK) { 813 u8 *args = rq->buffer; 814 u8 sel; 815 816 if (!args) 817 goto done; 818#ifdef DEBUG 819 printk("%s: DRIVE_TASK_CMD ", drive->name); 820 printk("cmd=0x%02x ", args[0]); 821 printk("fr=0x%02x ", args[1]); 822 printk("ns=0x%02x ", args[2]); 823 printk("sc=0x%02x ", args[3]); 824 printk("lcyl=0x%02x ", args[4]); 825 printk("hcyl=0x%02x ", args[5]); 826 printk("sel=0x%02x\n", args[6]); 827#endif 828 hwif->OUTB(args[1], IDE_FEATURE_REG); 829 hwif->OUTB(args[3], IDE_SECTOR_REG); 830 hwif->OUTB(args[4], IDE_LCYL_REG); 831 hwif->OUTB(args[5], IDE_HCYL_REG); 832 sel = (args[6] & ~0x10); 833 if (drive->select.b.unit) 834 sel |= 0x10; 835 hwif->OUTB(sel, IDE_SELECT_REG); 836 ide_cmd(drive, args[0], args[2], &drive_cmd_intr); 837 return ide_started; 838 } else if (rq->flags & REQ_DRIVE_CMD) { 839 u8 *args = rq->buffer; 840 841 if (!args) 842 goto done; 843#ifdef DEBUG 844 printk("%s: DRIVE_CMD ", drive->name); 845 printk("cmd=0x%02x ", args[0]); 846 printk("sc=0x%02x ", args[1]); 847 printk("fr=0x%02x ", args[2]); 848 printk("xx=0x%02x\n", args[3]); 849#endif 850 if (args[0] == WIN_SMART) { 851 hwif->OUTB(0x4f, IDE_LCYL_REG); 852 hwif->OUTB(0xc2, IDE_HCYL_REG); 853 hwif->OUTB(args[2],IDE_FEATURE_REG); 854 hwif->OUTB(args[1],IDE_SECTOR_REG); 855 ide_cmd(drive, args[0], args[3], &drive_cmd_intr); 856 return ide_started; 857 } 858 hwif->OUTB(args[2],IDE_FEATURE_REG); 859 ide_cmd(drive, args[0], args[1], &drive_cmd_intr); 860 return ide_started; 861 } 862 863done: 864 /* 865 * NULL is actually a valid way of waiting for 866 * all current requests to be flushed from the queue. 867 */ 868#ifdef DEBUG 869 printk("%s: DRIVE_CMD (null)\n", drive->name); 870#endif 871 ide_end_drive_cmd(drive, 872 hwif->INB(IDE_STATUS_REG), 873 hwif->INB(IDE_ERROR_REG)); 874 return ide_stopped; 875} 876 877/** 878 * start_request - start of I/O and command issuing for IDE 879 * 880 * start_request() initiates handling of a new I/O request. It 881 * accepts commands and I/O (read/write) requests. It also does 882 * the final remapping for weird stuff like EZDrive. Once 883 * device mapper can work sector level the EZDrive stuff can go away 884 * 885 * FIXME: this function needs a rename 886 */ 887 888static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) 889{ 890 ide_startstop_t startstop; 891 sector_t block; 892 893 BUG_ON(!(rq->flags & REQ_STARTED)); 894 895#ifdef DEBUG 896 printk("%s: start_request: current=0x%08lx\n", 897 HWIF(drive)->name, (unsigned long) rq); 898#endif 899 900 /* bail early if we've exceeded max_failures */ 901 if (drive->max_failures && (drive->failures > drive->max_failures)) { 902 goto kill_rq; 903 } 904 905 block = rq->sector; 906 if (blk_fs_request(rq) && 907 (drive->media == ide_disk || drive->media == ide_floppy)) { 908 block += drive->sect0; 909 } 910 /* Yecch - this will shift the entire interval, 911 possibly killing some innocent following sector */ 912 if (block == 0 && drive->remap_0_to_1 == 1) 913 block = 1; /* redirect MBR access to EZ-Drive partn table */ 914 915 if (blk_pm_suspend_request(rq) && 916 rq->pm->pm_step == ide_pm_state_start_suspend) 917 /* Mark drive blocked when starting the suspend sequence. */ 918 drive->blocked = 1; 919 else if (blk_pm_resume_request(rq) && 920 rq->pm->pm_step == ide_pm_state_start_resume) { 921 /* 922 * The first thing we do on wakeup is to wait for BSY bit to 923 * go away (with a looong timeout) as a drive on this hwif may 924 * just be POSTing itself. 925 * We do that before even selecting as the "other" device on 926 * the bus may be broken enough to walk on our toes at this 927 * point. 928 */ 929 int rc; 930#ifdef DEBUG_PM 931 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); 932#endif 933 rc = ide_wait_not_busy(HWIF(drive), 35000); 934 if (rc) 935 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); 936 SELECT_DRIVE(drive); 937 HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]); 938 rc = ide_wait_not_busy(HWIF(drive), 10000); 939 if (rc) 940 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); 941 } 942 943 SELECT_DRIVE(drive); 944 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { 945 printk(KERN_ERR "%s: drive not ready for command\n", drive->name); 946 return startstop; 947 } 948 if (!drive->special.all) { 949 ide_driver_t *drv; 950 951 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK)) 952 return execute_drive_cmd(drive, rq); 953 else if (rq->flags & REQ_DRIVE_TASKFILE) 954 return execute_drive_cmd(drive, rq); 955 else if (blk_pm_request(rq)) { 956#ifdef DEBUG_PM 957 printk("%s: start_power_step(step: %d)\n", 958 drive->name, rq->pm->pm_step); 959#endif 960 startstop = ide_start_power_step(drive, rq); 961 if (startstop == ide_stopped && 962 rq->pm->pm_step == ide_pm_state_completed) 963 ide_complete_pm_request(drive, rq); 964 return startstop; 965 } 966 967 drv = *(ide_driver_t **)rq->rq_disk->private_data; 968 return drv->do_request(drive, rq, block); 969 } 970 return do_special(drive); 971kill_rq: 972 ide_kill_rq(drive, rq); 973 return ide_stopped; 974} 975 976/** 977 * ide_stall_queue - pause an IDE device 978 * @drive: drive to stall 979 * @timeout: time to stall for (jiffies) 980 * 981 * ide_stall_queue() can be used by a drive to give excess bandwidth back 982 * to the hwgroup by sleeping for timeout jiffies. 983 */ 984 985void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) 986{ 987 if (timeout > WAIT_WORSTCASE) 988 timeout = WAIT_WORSTCASE; 989 drive->sleep = timeout + jiffies; 990 drive->sleeping = 1; 991} 992 993EXPORT_SYMBOL(ide_stall_queue); 994 995#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) 996 997/** 998 * choose_drive - select a drive to service 999 * @hwgroup: hardware group to select on 1000 * 1001 * choose_drive() selects the next drive which will be serviced. 1002 * This is necessary because the IDE layer can't issue commands 1003 * to both drives on the same cable, unlike SCSI. 1004 */ 1005 1006static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) 1007{ 1008 ide_drive_t *drive, *best; 1009 1010repeat: 1011 best = NULL; 1012 drive = hwgroup->drive; 1013 1014 /* 1015 * drive is doing pre-flush, ordered write, post-flush sequence. even 1016 * though that is 3 requests, it must be seen as a single transaction. 1017 * we must not preempt this drive until that is complete 1018 */ 1019 if (blk_queue_flushing(drive->queue)) { 1020 /* 1021 * small race where queue could get replugged during 1022 * the 3-request flush cycle, just yank the plug since 1023 * we want it to finish asap 1024 */ 1025 blk_remove_plug(drive->queue); 1026 return drive; 1027 } 1028 1029 do { 1030 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) 1031 && !elv_queue_empty(drive->queue)) { 1032 if (!best 1033 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) 1034 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) 1035 { 1036 if (!blk_queue_plugged(drive->queue)) 1037 best = drive; 1038 } 1039 } 1040 } while ((drive = drive->next) != hwgroup->drive); 1041 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { 1042 long t = (signed long)(WAKEUP(best) - jiffies); 1043 if (t >= WAIT_MIN_SLEEP) { 1044 /* 1045 * We *may* have some time to spare, but first let's see if 1046 * someone can potentially benefit from our nice mood today.. 1047 */ 1048 drive = best->next; 1049 do { 1050 if (!drive->sleeping 1051 && time_before(jiffies - best->service_time, WAKEUP(drive)) 1052 && time_before(WAKEUP(drive), jiffies + t)) 1053 { 1054 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); 1055 goto repeat; 1056 } 1057 } while ((drive = drive->next) != best); 1058 } 1059 } 1060 return best; 1061} 1062 1063/* 1064 * Issue a new request to a drive from hwgroup 1065 * Caller must have already done spin_lock_irqsave(&ide_lock, ..); 1066 * 1067 * A hwgroup is a serialized group of IDE interfaces. Usually there is 1068 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) 1069 * may have both interfaces in a single hwgroup to "serialize" access. 1070 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped 1071 * together into one hwgroup for serialized access. 1072 * 1073 * Note also that several hwgroups can end up sharing a single IRQ, 1074 * possibly along with many other devices. This is especially common in 1075 * PCI-based systems with off-board IDE controller cards. 1076 * 1077 * The IDE driver uses the single global ide_lock spinlock to protect 1078 * access to the request queues, and to protect the hwgroup->busy flag. 1079 * 1080 * The first thread into the driver for a particular hwgroup sets the 1081 * hwgroup->busy flag to indicate that this hwgroup is now active, 1082 * and then initiates processing of the top request from the request queue. 1083 * 1084 * Other threads attempting entry notice the busy setting, and will simply 1085 * queue their new requests and exit immediately. Note that hwgroup->busy 1086 * remains set even when the driver is merely awaiting the next interrupt. 1087 * Thus, the meaning is "this hwgroup is busy processing a request". 1088 * 1089 * When processing of a request completes, the completing thread or IRQ-handler 1090 * will start the next request from the queue. If no more work remains, 1091 * the driver will clear the hwgroup->busy flag and exit. 1092 * 1093 * The ide_lock (spinlock) is used to protect all access to the 1094 * hwgroup->busy flag, but is otherwise not needed for most processing in 1095 * the driver. This makes the driver much more friendlier to shared IRQs 1096 * than previous designs, while remaining 100% (?) SMP safe and capable. 1097 */ 1098static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) 1099{ 1100 ide_drive_t *drive; 1101 ide_hwif_t *hwif; 1102 struct request *rq; 1103 ide_startstop_t startstop; 1104 int loops = 0; 1105 1106 /* for atari only: POSSIBLY BROKEN HERE(?) */ 1107 ide_get_lock(ide_intr, hwgroup); 1108 1109 /* caller must own ide_lock */ 1110 BUG_ON(!irqs_disabled()); 1111 1112 while (!hwgroup->busy) { 1113 hwgroup->busy = 1; 1114 drive = choose_drive(hwgroup); 1115 if (drive == NULL) { 1116 int sleeping = 0; 1117 unsigned long sleep = 0; /* shut up, gcc */ 1118 hwgroup->rq = NULL; 1119 drive = hwgroup->drive; 1120 do { 1121 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { 1122 sleeping = 1; 1123 sleep = drive->sleep; 1124 } 1125 } while ((drive = drive->next) != hwgroup->drive); 1126 if (sleeping) { 1127 /* 1128 * Take a short snooze, and then wake up this hwgroup again. 1129 * This gives other hwgroups on the same a chance to 1130 * play fairly with us, just in case there are big differences 1131 * in relative throughputs.. don't want to hog the cpu too much. 1132 */ 1133 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) 1134 sleep = jiffies + WAIT_MIN_SLEEP; 1135#if 1 1136 if (timer_pending(&hwgroup->timer)) 1137 printk(KERN_CRIT "ide_set_handler: timer already active\n"); 1138#endif 1139 /* so that ide_timer_expiry knows what to do */ 1140 hwgroup->sleeping = 1; 1141 mod_timer(&hwgroup->timer, sleep); 1142 /* we purposely leave hwgroup->busy==1 1143 * while sleeping */ 1144 } else { 1145 /* Ugly, but how can we sleep for the lock 1146 * otherwise? perhaps from tq_disk? 1147 */ 1148 1149 /* for atari only */ 1150 ide_release_lock(); 1151 hwgroup->busy = 0; 1152 } 1153 1154 /* no more work for this hwgroup (for now) */ 1155 return; 1156 } 1157 again: 1158 hwif = HWIF(drive); 1159 if (hwgroup->hwif->sharing_irq && 1160 hwif != hwgroup->hwif && 1161 hwif->io_ports[IDE_CONTROL_OFFSET]) { 1162 /* set nIEN for previous hwif */ 1163 SELECT_INTERRUPT(drive); 1164 } 1165 hwgroup->hwif = hwif; 1166 hwgroup->drive = drive; 1167 drive->sleeping = 0; 1168 drive->service_start = jiffies; 1169 1170 if (blk_queue_plugged(drive->queue)) { 1171 printk(KERN_ERR "ide: huh? queue was plugged!\n"); 1172 break; 1173 } 1174 1175 /* 1176 * we know that the queue isn't empty, but this can happen 1177 * if the q->prep_rq_fn() decides to kill a request 1178 */ 1179 rq = elv_next_request(drive->queue); 1180 if (!rq) { 1181 hwgroup->busy = 0; 1182 break; 1183 } 1184 1185 /* 1186 * Sanity: don't accept a request that isn't a PM request 1187 * if we are currently power managed. This is very important as 1188 * blk_stop_queue() doesn't prevent the elv_next_request() 1189 * above to return us whatever is in the queue. Since we call 1190 * ide_do_request() ourselves, we end up taking requests while 1191 * the queue is blocked... 1192 * 1193 * We let requests forced at head of queue with ide-preempt 1194 * though. I hope that doesn't happen too much, hopefully not 1195 * unless the subdriver triggers such a thing in its own PM 1196 * state machine. 1197 * 1198 * We count how many times we loop here to make sure we service 1199 * all drives in the hwgroup without looping for ever 1200 */ 1201 if (drive->blocked && !blk_pm_request(rq) && !(rq->flags & REQ_PREEMPT)) { 1202 drive = drive->next ? drive->next : hwgroup->drive; 1203 if (loops++ < 4 && !blk_queue_plugged(drive->queue)) 1204 goto again; 1205 /* We clear busy, there should be no pending ATA command at this point. */ 1206 hwgroup->busy = 0; 1207 break; 1208 } 1209 1210 hwgroup->rq = rq; 1211 1212 /* 1213 * Some systems have trouble with IDE IRQs arriving while 1214 * the driver is still setting things up. So, here we disable 1215 * the IRQ used by this interface while the request is being started. 1216 * This may look bad at first, but pretty much the same thing 1217 * happens anyway when any interrupt comes in, IDE or otherwise 1218 * -- the kernel masks the IRQ while it is being handled. 1219 */ 1220 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1221 disable_irq_nosync(hwif->irq); 1222 spin_unlock(&ide_lock); 1223 local_irq_enable(); 1224 /* allow other IRQs while we start this request */ 1225 startstop = start_request(drive, rq); 1226 spin_lock_irq(&ide_lock); 1227 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1228 enable_irq(hwif->irq); 1229 if (startstop == ide_stopped) 1230 hwgroup->busy = 0; 1231 } 1232} 1233 1234/* 1235 * Passes the stuff to ide_do_request 1236 */ 1237void do_ide_request(request_queue_t *q) 1238{ 1239 ide_drive_t *drive = q->queuedata; 1240 1241 ide_do_request(HWGROUP(drive), IDE_NO_IRQ); 1242} 1243 1244/* 1245 * un-busy the hwgroup etc, and clear any pending DMA status. we want to 1246 * retry the current request in pio mode instead of risking tossing it 1247 * all away 1248 */ 1249static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) 1250{ 1251 ide_hwif_t *hwif = HWIF(drive); 1252 struct request *rq; 1253 ide_startstop_t ret = ide_stopped; 1254 1255 /* 1256 * end current dma transaction 1257 */ 1258 1259 if (error < 0) { 1260 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); 1261 (void)HWIF(drive)->ide_dma_end(drive); 1262 ret = ide_error(drive, "dma timeout error", 1263 hwif->INB(IDE_STATUS_REG)); 1264 } else { 1265 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); 1266 (void) hwif->ide_dma_timeout(drive); 1267 } 1268 1269 /* 1270 * disable dma for now, but remember that we did so because of 1271 * a timeout -- we'll reenable after we finish this next request 1272 * (or rather the first chunk of it) in pio. 1273 */ 1274 drive->retry_pio++; 1275 drive->state = DMA_PIO_RETRY; 1276 (void) hwif->ide_dma_off_quietly(drive); 1277 1278 /* 1279 * un-busy drive etc (hwgroup->busy is cleared on return) and 1280 * make sure request is sane 1281 */ 1282 rq = HWGROUP(drive)->rq; 1283 HWGROUP(drive)->rq = NULL; 1284 1285 rq->errors = 0; 1286 1287 if (!rq->bio) 1288 goto out; 1289 1290 rq->sector = rq->bio->bi_sector; 1291 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; 1292 rq->hard_cur_sectors = rq->current_nr_sectors; 1293 rq->buffer = bio_data(rq->bio); 1294out: 1295 return ret; 1296} 1297 1298/** 1299 * ide_timer_expiry - handle lack of an IDE interrupt 1300 * @data: timer callback magic (hwgroup) 1301 * 1302 * An IDE command has timed out before the expected drive return 1303 * occurred. At this point we attempt to clean up the current 1304 * mess. If the current handler includes an expiry handler then 1305 * we invoke the expiry handler, and providing it is happy the 1306 * work is done. If that fails we apply generic recovery rules 1307 * invoking the handler and checking the drive DMA status. We 1308 * have an excessively incestuous relationship with the DMA 1309 * logic that wants cleaning up. 1310 */ 1311 1312void ide_timer_expiry (unsigned long data) 1313{ 1314 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; 1315 ide_handler_t *handler; 1316 ide_expiry_t *expiry; 1317 unsigned long flags; 1318 unsigned long wait = -1; 1319 1320 spin_lock_irqsave(&ide_lock, flags); 1321 1322 if ((handler = hwgroup->handler) == NULL) { 1323 /* 1324 * Either a marginal timeout occurred 1325 * (got the interrupt just as timer expired), 1326 * or we were "sleeping" to give other devices a chance. 1327 * Either way, we don't really want to complain about anything. 1328 */ 1329 if (hwgroup->sleeping) { 1330 hwgroup->sleeping = 0; 1331 hwgroup->busy = 0; 1332 } 1333 } else { 1334 ide_drive_t *drive = hwgroup->drive; 1335 if (!drive) { 1336 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); 1337 hwgroup->handler = NULL; 1338 } else { 1339 ide_hwif_t *hwif; 1340 ide_startstop_t startstop = ide_stopped; 1341 if (!hwgroup->busy) { 1342 hwgroup->busy = 1; /* paranoia */ 1343 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); 1344 } 1345 if ((expiry = hwgroup->expiry) != NULL) { 1346 /* continue */ 1347 if ((wait = expiry(drive)) > 0) { 1348 /* reset timer */ 1349 hwgroup->timer.expires = jiffies + wait; 1350 add_timer(&hwgroup->timer); 1351 spin_unlock_irqrestore(&ide_lock, flags); 1352 return; 1353 } 1354 } 1355 hwgroup->handler = NULL; 1356 /* 1357 * We need to simulate a real interrupt when invoking 1358 * the handler() function, which means we need to 1359 * globally mask the specific IRQ: 1360 */ 1361 spin_unlock(&ide_lock); 1362 hwif = HWIF(drive); 1363#if DISABLE_IRQ_NOSYNC 1364 disable_irq_nosync(hwif->irq); 1365#else 1366 /* disable_irq_nosync ?? */ 1367 disable_irq(hwif->irq); 1368#endif /* DISABLE_IRQ_NOSYNC */ 1369 /* local CPU only, 1370 * as if we were handling an interrupt */ 1371 local_irq_disable(); 1372 if (hwgroup->polling) { 1373 startstop = handler(drive); 1374 } else if (drive_is_ready(drive)) { 1375 if (drive->waiting_for_dma) 1376 (void) hwgroup->hwif->ide_dma_lostirq(drive); 1377 (void)ide_ack_intr(hwif); 1378 printk(KERN_WARNING "%s: lost interrupt\n", drive->name); 1379 startstop = handler(drive); 1380 } else { 1381 if (drive->waiting_for_dma) { 1382 startstop = ide_dma_timeout_retry(drive, wait); 1383 } else 1384 startstop = 1385 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG)); 1386 } 1387 drive->service_time = jiffies - drive->service_start; 1388 spin_lock_irq(&ide_lock); 1389 enable_irq(hwif->irq); 1390 if (startstop == ide_stopped) 1391 hwgroup->busy = 0; 1392 } 1393 } 1394 ide_do_request(hwgroup, IDE_NO_IRQ); 1395 spin_unlock_irqrestore(&ide_lock, flags); 1396} 1397 1398/** 1399 * unexpected_intr - handle an unexpected IDE interrupt 1400 * @irq: interrupt line 1401 * @hwgroup: hwgroup being processed 1402 * 1403 * There's nothing really useful we can do with an unexpected interrupt, 1404 * other than reading the status register (to clear it), and logging it. 1405 * There should be no way that an irq can happen before we're ready for it, 1406 * so we needn't worry much about losing an "important" interrupt here. 1407 * 1408 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever 1409 * the drive enters "idle", "standby", or "sleep" mode, so if the status 1410 * looks "good", we just ignore the interrupt completely. 1411 * 1412 * This routine assumes __cli() is in effect when called. 1413 * 1414 * If an unexpected interrupt happens on irq15 while we are handling irq14 1415 * and if the two interfaces are "serialized" (CMD640), then it looks like 1416 * we could screw up by interfering with a new request being set up for 1417 * irq15. 1418 * 1419 * In reality, this is a non-issue. The new command is not sent unless 1420 * the drive is ready to accept one, in which case we know the drive is 1421 * not trying to interrupt us. And ide_set_handler() is always invoked 1422 * before completing the issuance of any new drive command, so we will not 1423 * be accidentally invoked as a result of any valid command completion 1424 * interrupt. 1425 * 1426 * Note that we must walk the entire hwgroup here. We know which hwif 1427 * is doing the current command, but we don't know which hwif burped 1428 * mysteriously. 1429 */ 1430 1431static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) 1432{ 1433 u8 stat; 1434 ide_hwif_t *hwif = hwgroup->hwif; 1435 1436 /* 1437 * handle the unexpected interrupt 1438 */ 1439 do { 1440 if (hwif->irq == irq) { 1441 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1442 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { 1443 /* Try to not flood the console with msgs */ 1444 static unsigned long last_msgtime, count; 1445 ++count; 1446 if (time_after(jiffies, last_msgtime + HZ)) { 1447 last_msgtime = jiffies; 1448 printk(KERN_ERR "%s%s: unexpected interrupt, " 1449 "status=0x%02x, count=%ld\n", 1450 hwif->name, 1451 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); 1452 } 1453 } 1454 } 1455 } while ((hwif = hwif->next) != hwgroup->hwif); 1456} 1457 1458/** 1459 * ide_intr - default IDE interrupt handler 1460 * @irq: interrupt number 1461 * @dev_id: hwif group 1462 * @regs: unused weirdness from the kernel irq layer 1463 * 1464 * This is the default IRQ handler for the IDE layer. You should 1465 * not need to override it. If you do be aware it is subtle in 1466 * places 1467 * 1468 * hwgroup->hwif is the interface in the group currently performing 1469 * a command. hwgroup->drive is the drive and hwgroup->handler is 1470 * the IRQ handler to call. As we issue a command the handlers 1471 * step through multiple states, reassigning the handler to the 1472 * next step in the process. Unlike a smart SCSI controller IDE 1473 * expects the main processor to sequence the various transfer 1474 * stages. We also manage a poll timer to catch up with most 1475 * timeout situations. There are still a few where the handlers 1476 * don't ever decide to give up. 1477 * 1478 * The handler eventually returns ide_stopped to indicate the 1479 * request completed. At this point we issue the next request 1480 * on the hwgroup and the process begins again. 1481 */ 1482 1483irqreturn_t ide_intr (int irq, void *dev_id, struct pt_regs *regs) 1484{ 1485 unsigned long flags; 1486 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; 1487 ide_hwif_t *hwif; 1488 ide_drive_t *drive; 1489 ide_handler_t *handler; 1490 ide_startstop_t startstop; 1491 1492 spin_lock_irqsave(&ide_lock, flags); 1493 hwif = hwgroup->hwif; 1494 1495 if (!ide_ack_intr(hwif)) { 1496 spin_unlock_irqrestore(&ide_lock, flags); 1497 return IRQ_NONE; 1498 } 1499 1500 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { 1501 /* 1502 * Not expecting an interrupt from this drive. 1503 * That means this could be: 1504 * (1) an interrupt from another PCI device 1505 * sharing the same PCI INT# as us. 1506 * or (2) a drive just entered sleep or standby mode, 1507 * and is interrupting to let us know. 1508 * or (3) a spurious interrupt of unknown origin. 1509 * 1510 * For PCI, we cannot tell the difference, 1511 * so in that case we just ignore it and hope it goes away. 1512 * 1513 * FIXME: unexpected_intr should be hwif-> then we can 1514 * remove all the ifdef PCI crap 1515 */ 1516#ifdef CONFIG_BLK_DEV_IDEPCI 1517 if (hwif->pci_dev && !hwif->pci_dev->vendor) 1518#endif /* CONFIG_BLK_DEV_IDEPCI */ 1519 { 1520 /* 1521 * Probably not a shared PCI interrupt, 1522 * so we can safely try to do something about it: 1523 */ 1524 unexpected_intr(irq, hwgroup); 1525#ifdef CONFIG_BLK_DEV_IDEPCI 1526 } else { 1527 /* 1528 * Whack the status register, just in case 1529 * we have a leftover pending IRQ. 1530 */ 1531 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1532#endif /* CONFIG_BLK_DEV_IDEPCI */ 1533 } 1534 spin_unlock_irqrestore(&ide_lock, flags); 1535 return IRQ_NONE; 1536 } 1537 drive = hwgroup->drive; 1538 if (!drive) { 1539 /* 1540 * This should NEVER happen, and there isn't much 1541 * we could do about it here. 1542 * 1543 * [Note - this can occur if the drive is hot unplugged] 1544 */ 1545 spin_unlock_irqrestore(&ide_lock, flags); 1546 return IRQ_HANDLED; 1547 } 1548 if (!drive_is_ready(drive)) { 1549 /* 1550 * This happens regularly when we share a PCI IRQ with 1551 * another device. Unfortunately, it can also happen 1552 * with some buggy drives that trigger the IRQ before 1553 * their status register is up to date. Hopefully we have 1554 * enough advance overhead that the latter isn't a problem. 1555 */ 1556 spin_unlock_irqrestore(&ide_lock, flags); 1557 return IRQ_NONE; 1558 } 1559 if (!hwgroup->busy) { 1560 hwgroup->busy = 1; /* paranoia */ 1561 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); 1562 } 1563 hwgroup->handler = NULL; 1564 del_timer(&hwgroup->timer); 1565 spin_unlock(&ide_lock); 1566 1567 if (drive->unmask) 1568 local_irq_enable(); 1569 /* service this interrupt, may set handler for next interrupt */ 1570 startstop = handler(drive); 1571 spin_lock_irq(&ide_lock); 1572 1573 /* 1574 * Note that handler() may have set things up for another 1575 * interrupt to occur soon, but it cannot happen until 1576 * we exit from this routine, because it will be the 1577 * same irq as is currently being serviced here, and Linux 1578 * won't allow another of the same (on any CPU) until we return. 1579 */ 1580 drive->service_time = jiffies - drive->service_start; 1581 if (startstop == ide_stopped) { 1582 if (hwgroup->handler == NULL) { /* paranoia */ 1583 hwgroup->busy = 0; 1584 ide_do_request(hwgroup, hwif->irq); 1585 } else { 1586 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " 1587 "on exit\n", drive->name); 1588 } 1589 } 1590 spin_unlock_irqrestore(&ide_lock, flags); 1591 return IRQ_HANDLED; 1592} 1593 1594/** 1595 * ide_init_drive_cmd - initialize a drive command request 1596 * @rq: request object 1597 * 1598 * Initialize a request before we fill it in and send it down to 1599 * ide_do_drive_cmd. Commands must be set up by this function. Right 1600 * now it doesn't do a lot, but if that changes abusers will have a 1601 * nasty suprise. 1602 */ 1603 1604void ide_init_drive_cmd (struct request *rq) 1605{ 1606 memset(rq, 0, sizeof(*rq)); 1607 rq->flags = REQ_DRIVE_CMD; 1608 rq->ref_count = 1; 1609} 1610 1611EXPORT_SYMBOL(ide_init_drive_cmd); 1612 1613/** 1614 * ide_do_drive_cmd - issue IDE special command 1615 * @drive: device to issue command 1616 * @rq: request to issue 1617 * @action: action for processing 1618 * 1619 * This function issues a special IDE device request 1620 * onto the request queue. 1621 * 1622 * If action is ide_wait, then the rq is queued at the end of the 1623 * request queue, and the function sleeps until it has been processed. 1624 * This is for use when invoked from an ioctl handler. 1625 * 1626 * If action is ide_preempt, then the rq is queued at the head of 1627 * the request queue, displacing the currently-being-processed 1628 * request and this function returns immediately without waiting 1629 * for the new rq to be completed. This is VERY DANGEROUS, and is 1630 * intended for careful use by the ATAPI tape/cdrom driver code. 1631 * 1632 * If action is ide_end, then the rq is queued at the end of the 1633 * request queue, and the function returns immediately without waiting 1634 * for the new rq to be completed. This is again intended for careful 1635 * use by the ATAPI tape/cdrom driver code. 1636 */ 1637 1638int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) 1639{ 1640 unsigned long flags; 1641 ide_hwgroup_t *hwgroup = HWGROUP(drive); 1642 DECLARE_COMPLETION(wait); 1643 int where = ELEVATOR_INSERT_BACK, err; 1644 int must_wait = (action == ide_wait || action == ide_head_wait); 1645 1646 rq->errors = 0; 1647 rq->rq_status = RQ_ACTIVE; 1648 1649 /* 1650 * we need to hold an extra reference to request for safe inspection 1651 * after completion 1652 */ 1653 if (must_wait) { 1654 rq->ref_count++; 1655 rq->waiting = &wait; 1656 rq->end_io = blk_end_sync_rq; 1657 } 1658 1659 spin_lock_irqsave(&ide_lock, flags); 1660 if (action == ide_preempt) 1661 hwgroup->rq = NULL; 1662 if (action == ide_preempt || action == ide_head_wait) { 1663 where = ELEVATOR_INSERT_FRONT; 1664 rq->flags |= REQ_PREEMPT; 1665 } 1666 __elv_add_request(drive->queue, rq, where, 0); 1667 ide_do_request(hwgroup, IDE_NO_IRQ); 1668 spin_unlock_irqrestore(&ide_lock, flags); 1669 1670 err = 0; 1671 if (must_wait) { 1672 wait_for_completion(&wait); 1673 rq->waiting = NULL; 1674 if (rq->errors) 1675 err = -EIO; 1676 1677 blk_put_request(rq); 1678 } 1679 1680 return err; 1681} 1682 1683EXPORT_SYMBOL(ide_do_drive_cmd); 1684