ide-io.c revision ad3caddaa1708e506f20b8e25a4a8ae586fc7d5b
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 58static int __ide_end_request(ide_drive_t *drive, struct request *rq, 59 int uptodate, 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 blkdev_dequeue_request(rq); 87 HWGROUP(drive)->rq = NULL; 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 struct request *rq; 109 unsigned long flags; 110 int ret = 1; 111 112 /* 113 * room for locking improvements here, the calls below don't 114 * need the queue lock held at all 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 ret = __ide_end_request(drive, rq, uptodate, nr_sectors); 123 124 spin_unlock_irqrestore(&ide_lock, flags); 125 return ret; 126} 127EXPORT_SYMBOL(ide_end_request); 128 129/* 130 * Power Management state machine. This one is rather trivial for now, 131 * we should probably add more, like switching back to PIO on suspend 132 * to help some BIOSes, re-do the door locking on resume, etc... 133 */ 134 135enum { 136 ide_pm_flush_cache = ide_pm_state_start_suspend, 137 idedisk_pm_standby, 138 139 idedisk_pm_idle = ide_pm_state_start_resume, 140 ide_pm_restore_dma, 141}; 142 143static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error) 144{ 145 struct request_pm_state *pm = rq->end_io_data; 146 147 if (drive->media != ide_disk) 148 return; 149 150 switch (pm->pm_step) { 151 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */ 152 if (pm->pm_state == PM_EVENT_FREEZE) 153 pm->pm_step = ide_pm_state_completed; 154 else 155 pm->pm_step = idedisk_pm_standby; 156 break; 157 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */ 158 pm->pm_step = ide_pm_state_completed; 159 break; 160 case idedisk_pm_idle: /* Resume step 1 (idle) complete */ 161 pm->pm_step = ide_pm_restore_dma; 162 break; 163 } 164} 165 166static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq) 167{ 168 struct request_pm_state *pm = rq->end_io_data; 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 (pm->pm_step == idedisk_pm_idle) 176 pm->pm_step = ide_pm_restore_dma; 177 } 178 179 switch (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 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 struct request_pm_state *pm = rq->end_io_data; 369#ifdef DEBUG_PM 370 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n", 371 drive->name, rq->pm->pm_step, stat, err); 372#endif 373 ide_complete_power_step(drive, rq, stat, err); 374 if (pm->pm_step == ide_pm_state_completed) 375 ide_complete_pm_request(drive, rq); 376 return; 377 } 378 379 spin_lock_irqsave(&ide_lock, flags); 380 blkdev_dequeue_request(rq); 381 HWGROUP(drive)->rq = NULL; 382 rq->errors = err; 383 end_that_request_last(rq, !rq->errors); 384 spin_unlock_irqrestore(&ide_lock, flags); 385} 386 387EXPORT_SYMBOL(ide_end_drive_cmd); 388 389/** 390 * try_to_flush_leftover_data - flush junk 391 * @drive: drive to flush 392 * 393 * try_to_flush_leftover_data() is invoked in response to a drive 394 * unexpectedly having its DRQ_STAT bit set. As an alternative to 395 * resetting the drive, this routine tries to clear the condition 396 * by read a sector's worth of data from the drive. Of course, 397 * this may not help if the drive is *waiting* for data from *us*. 398 */ 399static void try_to_flush_leftover_data (ide_drive_t *drive) 400{ 401 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS; 402 403 if (drive->media != ide_disk) 404 return; 405 while (i > 0) { 406 u32 buffer[16]; 407 u32 wcount = (i > 16) ? 16 : i; 408 409 i -= wcount; 410 HWIF(drive)->ata_input_data(drive, buffer, wcount); 411 } 412} 413 414static void ide_kill_rq(ide_drive_t *drive, struct request *rq) 415{ 416 if (rq->rq_disk) { 417 ide_driver_t *drv; 418 419 drv = *(ide_driver_t **)rq->rq_disk->private_data; 420 drv->end_request(drive, 0, 0); 421 } else 422 ide_end_request(drive, 0, 0); 423} 424 425static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 426{ 427 ide_hwif_t *hwif = drive->hwif; 428 429 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 430 /* other bits are useless when BUSY */ 431 rq->errors |= ERROR_RESET; 432 } else if (stat & ERR_STAT) { 433 /* err has different meaning on cdrom and tape */ 434 if (err == ABRT_ERR) { 435 if (drive->select.b.lba && 436 /* some newer drives don't support WIN_SPECIFY */ 437 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY) 438 return ide_stopped; 439 } else if ((err & BAD_CRC) == BAD_CRC) { 440 /* UDMA crc error, just retry the operation */ 441 drive->crc_count++; 442 } else if (err & (BBD_ERR | ECC_ERR)) { 443 /* retries won't help these */ 444 rq->errors = ERROR_MAX; 445 } else if (err & TRK0_ERR) { 446 /* help it find track zero */ 447 rq->errors |= ERROR_RECAL; 448 } 449 } 450 451 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ) 452 try_to_flush_leftover_data(drive); 453 454 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 455 /* force an abort */ 456 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 457 458 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) 459 ide_kill_rq(drive, rq); 460 else { 461 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 462 ++rq->errors; 463 return ide_do_reset(drive); 464 } 465 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) 466 drive->special.b.recalibrate = 1; 467 ++rq->errors; 468 } 469 return ide_stopped; 470} 471 472static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 473{ 474 ide_hwif_t *hwif = drive->hwif; 475 476 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 477 /* other bits are useless when BUSY */ 478 rq->errors |= ERROR_RESET; 479 } else { 480 /* add decoding error stuff */ 481 } 482 483 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 484 /* force an abort */ 485 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 486 487 if (rq->errors >= ERROR_MAX) { 488 ide_kill_rq(drive, rq); 489 } else { 490 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 491 ++rq->errors; 492 return ide_do_reset(drive); 493 } 494 ++rq->errors; 495 } 496 497 return ide_stopped; 498} 499 500ide_startstop_t 501__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 502{ 503 if (drive->media == ide_disk) 504 return ide_ata_error(drive, rq, stat, err); 505 return ide_atapi_error(drive, rq, stat, err); 506} 507 508EXPORT_SYMBOL_GPL(__ide_error); 509 510/** 511 * ide_error - handle an error on the IDE 512 * @drive: drive the error occurred on 513 * @msg: message to report 514 * @stat: status bits 515 * 516 * ide_error() takes action based on the error returned by the drive. 517 * For normal I/O that may well include retries. We deal with 518 * both new-style (taskfile) and old style command handling here. 519 * In the case of taskfile command handling there is work left to 520 * do 521 */ 522 523ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) 524{ 525 struct request *rq; 526 u8 err; 527 528 err = ide_dump_status(drive, msg, stat); 529 530 if ((rq = HWGROUP(drive)->rq) == NULL) 531 return ide_stopped; 532 533 /* retry only "normal" I/O: */ 534 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) { 535 rq->errors = 1; 536 ide_end_drive_cmd(drive, stat, err); 537 return ide_stopped; 538 } 539 540 if (rq->rq_disk) { 541 ide_driver_t *drv; 542 543 drv = *(ide_driver_t **)rq->rq_disk->private_data; 544 return drv->error(drive, rq, stat, err); 545 } else 546 return __ide_error(drive, rq, stat, err); 547} 548 549EXPORT_SYMBOL_GPL(ide_error); 550 551ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) 552{ 553 if (drive->media != ide_disk) 554 rq->errors |= ERROR_RESET; 555 556 ide_kill_rq(drive, rq); 557 558 return ide_stopped; 559} 560 561EXPORT_SYMBOL_GPL(__ide_abort); 562 563/** 564 * ide_abort - abort pending IDE operations 565 * @drive: drive the error occurred on 566 * @msg: message to report 567 * 568 * ide_abort kills and cleans up when we are about to do a 569 * host initiated reset on active commands. Longer term we 570 * want handlers to have sensible abort handling themselves 571 * 572 * This differs fundamentally from ide_error because in 573 * this case the command is doing just fine when we 574 * blow it away. 575 */ 576 577ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) 578{ 579 struct request *rq; 580 581 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) 582 return ide_stopped; 583 584 /* retry only "normal" I/O: */ 585 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK | REQ_DRIVE_TASKFILE)) { 586 rq->errors = 1; 587 ide_end_drive_cmd(drive, BUSY_STAT, 0); 588 return ide_stopped; 589 } 590 591 if (rq->rq_disk) { 592 ide_driver_t *drv; 593 594 drv = *(ide_driver_t **)rq->rq_disk->private_data; 595 return drv->abort(drive, rq); 596 } else 597 return __ide_abort(drive, rq); 598} 599 600/** 601 * ide_cmd - issue a simple drive command 602 * @drive: drive the command is for 603 * @cmd: command byte 604 * @nsect: sector byte 605 * @handler: handler for the command completion 606 * 607 * Issue a simple drive command with interrupts. 608 * The drive must be selected beforehand. 609 */ 610 611static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect, 612 ide_handler_t *handler) 613{ 614 ide_hwif_t *hwif = HWIF(drive); 615 if (IDE_CONTROL_REG) 616 hwif->OUTB(drive->ctl,IDE_CONTROL_REG); /* clear nIEN */ 617 SELECT_MASK(drive,0); 618 hwif->OUTB(nsect,IDE_NSECTOR_REG); 619 ide_execute_command(drive, cmd, handler, WAIT_CMD, NULL); 620} 621 622/** 623 * drive_cmd_intr - drive command completion interrupt 624 * @drive: drive the completion interrupt occurred on 625 * 626 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD. 627 * We do any necessary data reading and then wait for the drive to 628 * go non busy. At that point we may read the error data and complete 629 * the request 630 */ 631 632static ide_startstop_t drive_cmd_intr (ide_drive_t *drive) 633{ 634 struct request *rq = HWGROUP(drive)->rq; 635 ide_hwif_t *hwif = HWIF(drive); 636 u8 *args = (u8 *) rq->buffer; 637 u8 stat = hwif->INB(IDE_STATUS_REG); 638 int retries = 10; 639 640 local_irq_enable(); 641 if ((stat & DRQ_STAT) && args && args[3]) { 642 u8 io_32bit = drive->io_32bit; 643 drive->io_32bit = 0; 644 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS); 645 drive->io_32bit = io_32bit; 646 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--) 647 udelay(100); 648 } 649 650 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) 651 return ide_error(drive, "drive_cmd", stat); 652 /* calls ide_end_drive_cmd */ 653 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG)); 654 return ide_stopped; 655} 656 657static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task) 658{ 659 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect; 660 task->tfRegister[IDE_SECTOR_OFFSET] = drive->sect; 661 task->tfRegister[IDE_LCYL_OFFSET] = drive->cyl; 662 task->tfRegister[IDE_HCYL_OFFSET] = drive->cyl>>8; 663 task->tfRegister[IDE_SELECT_OFFSET] = ((drive->head-1)|drive->select.all)&0xBF; 664 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY; 665 666 task->handler = &set_geometry_intr; 667} 668 669static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task) 670{ 671 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect; 672 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE; 673 674 task->handler = &recal_intr; 675} 676 677static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task) 678{ 679 task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req; 680 task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT; 681 682 task->handler = &set_multmode_intr; 683} 684 685static ide_startstop_t ide_disk_special(ide_drive_t *drive) 686{ 687 special_t *s = &drive->special; 688 ide_task_t args; 689 690 memset(&args, 0, sizeof(ide_task_t)); 691 args.command_type = IDE_DRIVE_TASK_NO_DATA; 692 693 if (s->b.set_geometry) { 694 s->b.set_geometry = 0; 695 ide_init_specify_cmd(drive, &args); 696 } else if (s->b.recalibrate) { 697 s->b.recalibrate = 0; 698 ide_init_restore_cmd(drive, &args); 699 } else if (s->b.set_multmode) { 700 s->b.set_multmode = 0; 701 if (drive->mult_req > drive->id->max_multsect) 702 drive->mult_req = drive->id->max_multsect; 703 ide_init_setmult_cmd(drive, &args); 704 } else if (s->all) { 705 int special = s->all; 706 s->all = 0; 707 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); 708 return ide_stopped; 709 } 710 711 do_rw_taskfile(drive, &args); 712 713 return ide_started; 714} 715 716/** 717 * do_special - issue some special commands 718 * @drive: drive the command is for 719 * 720 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT 721 * commands to a drive. It used to do much more, but has been scaled 722 * back. 723 */ 724 725static ide_startstop_t do_special (ide_drive_t *drive) 726{ 727 special_t *s = &drive->special; 728 729#ifdef DEBUG 730 printk("%s: do_special: 0x%02x\n", drive->name, s->all); 731#endif 732 if (s->b.set_tune) { 733 s->b.set_tune = 0; 734 if (HWIF(drive)->tuneproc != NULL) 735 HWIF(drive)->tuneproc(drive, drive->tune_req); 736 return ide_stopped; 737 } else { 738 if (drive->media == ide_disk) 739 return ide_disk_special(drive); 740 741 s->all = 0; 742 drive->mult_req = 0; 743 return ide_stopped; 744 } 745} 746 747void ide_map_sg(ide_drive_t *drive, struct request *rq) 748{ 749 ide_hwif_t *hwif = drive->hwif; 750 struct scatterlist *sg = hwif->sg_table; 751 752 if (hwif->sg_mapped) /* needed by ide-scsi */ 753 return; 754 755 if ((rq->flags & REQ_DRIVE_TASKFILE) == 0) { 756 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); 757 } else { 758 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); 759 hwif->sg_nents = 1; 760 } 761} 762 763EXPORT_SYMBOL_GPL(ide_map_sg); 764 765void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) 766{ 767 ide_hwif_t *hwif = drive->hwif; 768 769 hwif->nsect = hwif->nleft = rq->nr_sectors; 770 hwif->cursg = hwif->cursg_ofs = 0; 771} 772 773EXPORT_SYMBOL_GPL(ide_init_sg_cmd); 774 775/** 776 * execute_drive_command - issue special drive command 777 * @drive: the drive to issue the command on 778 * @rq: the request structure holding the command 779 * 780 * execute_drive_cmd() issues a special drive command, usually 781 * initiated by ioctl() from the external hdparm program. The 782 * command can be a drive command, drive task or taskfile 783 * operation. Weirdly you can call it with NULL to wait for 784 * all commands to finish. Don't do this as that is due to change 785 */ 786 787static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, 788 struct request *rq) 789{ 790 ide_hwif_t *hwif = HWIF(drive); 791 if (rq->flags & REQ_DRIVE_TASKFILE) { 792 ide_task_t *args = rq->special; 793 794 if (!args) 795 goto done; 796 797 hwif->data_phase = args->data_phase; 798 799 switch (hwif->data_phase) { 800 case TASKFILE_MULTI_OUT: 801 case TASKFILE_OUT: 802 case TASKFILE_MULTI_IN: 803 case TASKFILE_IN: 804 ide_init_sg_cmd(drive, rq); 805 ide_map_sg(drive, rq); 806 default: 807 break; 808 } 809 810 if (args->tf_out_flags.all != 0) 811 return flagged_taskfile(drive, args); 812 return do_rw_taskfile(drive, args); 813 } else if (rq->flags & REQ_DRIVE_TASK) { 814 u8 *args = rq->buffer; 815 u8 sel; 816 817 if (!args) 818 goto done; 819#ifdef DEBUG 820 printk("%s: DRIVE_TASK_CMD ", drive->name); 821 printk("cmd=0x%02x ", args[0]); 822 printk("fr=0x%02x ", args[1]); 823 printk("ns=0x%02x ", args[2]); 824 printk("sc=0x%02x ", args[3]); 825 printk("lcyl=0x%02x ", args[4]); 826 printk("hcyl=0x%02x ", args[5]); 827 printk("sel=0x%02x\n", args[6]); 828#endif 829 hwif->OUTB(args[1], IDE_FEATURE_REG); 830 hwif->OUTB(args[3], IDE_SECTOR_REG); 831 hwif->OUTB(args[4], IDE_LCYL_REG); 832 hwif->OUTB(args[5], IDE_HCYL_REG); 833 sel = (args[6] & ~0x10); 834 if (drive->select.b.unit) 835 sel |= 0x10; 836 hwif->OUTB(sel, IDE_SELECT_REG); 837 ide_cmd(drive, args[0], args[2], &drive_cmd_intr); 838 return ide_started; 839 } else if (rq->flags & REQ_DRIVE_CMD) { 840 u8 *args = rq->buffer; 841 842 if (!args) 843 goto done; 844#ifdef DEBUG 845 printk("%s: DRIVE_CMD ", drive->name); 846 printk("cmd=0x%02x ", args[0]); 847 printk("sc=0x%02x ", args[1]); 848 printk("fr=0x%02x ", args[2]); 849 printk("xx=0x%02x\n", args[3]); 850#endif 851 if (args[0] == WIN_SMART) { 852 hwif->OUTB(0x4f, IDE_LCYL_REG); 853 hwif->OUTB(0xc2, IDE_HCYL_REG); 854 hwif->OUTB(args[2],IDE_FEATURE_REG); 855 hwif->OUTB(args[1],IDE_SECTOR_REG); 856 ide_cmd(drive, args[0], args[3], &drive_cmd_intr); 857 return ide_started; 858 } 859 hwif->OUTB(args[2],IDE_FEATURE_REG); 860 ide_cmd(drive, args[0], args[1], &drive_cmd_intr); 861 return ide_started; 862 } 863 864done: 865 /* 866 * NULL is actually a valid way of waiting for 867 * all current requests to be flushed from the queue. 868 */ 869#ifdef DEBUG 870 printk("%s: DRIVE_CMD (null)\n", drive->name); 871#endif 872 ide_end_drive_cmd(drive, 873 hwif->INB(IDE_STATUS_REG), 874 hwif->INB(IDE_ERROR_REG)); 875 return ide_stopped; 876} 877 878static void ide_check_pm_state(ide_drive_t *drive, struct request *rq) 879{ 880 struct request_pm_state *pm = rq->end_io_data; 881 882 if (blk_pm_suspend_request(rq) && 883 pm->pm_step == ide_pm_state_start_suspend) 884 /* Mark drive blocked when starting the suspend sequence. */ 885 drive->blocked = 1; 886 else if (blk_pm_resume_request(rq) && 887 pm->pm_step == ide_pm_state_start_resume) { 888 /* 889 * The first thing we do on wakeup is to wait for BSY bit to 890 * go away (with a looong timeout) as a drive on this hwif may 891 * just be POSTing itself. 892 * We do that before even selecting as the "other" device on 893 * the bus may be broken enough to walk on our toes at this 894 * point. 895 */ 896 int rc; 897#ifdef DEBUG_PM 898 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); 899#endif 900 rc = ide_wait_not_busy(HWIF(drive), 35000); 901 if (rc) 902 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); 903 SELECT_DRIVE(drive); 904 HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]); 905 rc = ide_wait_not_busy(HWIF(drive), 10000); 906 if (rc) 907 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); 908 } 909} 910 911/** 912 * start_request - start of I/O and command issuing for IDE 913 * 914 * start_request() initiates handling of a new I/O request. It 915 * accepts commands and I/O (read/write) requests. It also does 916 * the final remapping for weird stuff like EZDrive. Once 917 * device mapper can work sector level the EZDrive stuff can go away 918 * 919 * FIXME: this function needs a rename 920 */ 921 922static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) 923{ 924 ide_startstop_t startstop; 925 sector_t block; 926 927 BUG_ON(!(rq->flags & REQ_STARTED)); 928 929#ifdef DEBUG 930 printk("%s: start_request: current=0x%08lx\n", 931 HWIF(drive)->name, (unsigned long) rq); 932#endif 933 934 /* bail early if we've exceeded max_failures */ 935 if (drive->max_failures && (drive->failures > drive->max_failures)) { 936 goto kill_rq; 937 } 938 939 block = rq->sector; 940 if (blk_fs_request(rq) && 941 (drive->media == ide_disk || drive->media == ide_floppy)) { 942 block += drive->sect0; 943 } 944 /* Yecch - this will shift the entire interval, 945 possibly killing some innocent following sector */ 946 if (block == 0 && drive->remap_0_to_1 == 1) 947 block = 1; /* redirect MBR access to EZ-Drive partn table */ 948 949 if (blk_pm_request(rq)) 950 ide_check_pm_state(drive, rq); 951 952 SELECT_DRIVE(drive); 953 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { 954 printk(KERN_ERR "%s: drive not ready for command\n", drive->name); 955 return startstop; 956 } 957 if (!drive->special.all) { 958 ide_driver_t *drv; 959 960 if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK)) 961 return execute_drive_cmd(drive, rq); 962 else if (rq->flags & REQ_DRIVE_TASKFILE) 963 return execute_drive_cmd(drive, rq); 964 else if (blk_pm_request(rq)) { 965 struct request_pm_state *pm = rq->end_io_data; 966#ifdef DEBUG_PM 967 printk("%s: start_power_step(step: %d)\n", 968 drive->name, rq->pm->pm_step); 969#endif 970 startstop = ide_start_power_step(drive, rq); 971 if (startstop == ide_stopped && 972 pm->pm_step == ide_pm_state_completed) 973 ide_complete_pm_request(drive, rq); 974 return startstop; 975 } 976 977 drv = *(ide_driver_t **)rq->rq_disk->private_data; 978 return drv->do_request(drive, rq, block); 979 } 980 return do_special(drive); 981kill_rq: 982 ide_kill_rq(drive, rq); 983 return ide_stopped; 984} 985 986/** 987 * ide_stall_queue - pause an IDE device 988 * @drive: drive to stall 989 * @timeout: time to stall for (jiffies) 990 * 991 * ide_stall_queue() can be used by a drive to give excess bandwidth back 992 * to the hwgroup by sleeping for timeout jiffies. 993 */ 994 995void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) 996{ 997 if (timeout > WAIT_WORSTCASE) 998 timeout = WAIT_WORSTCASE; 999 drive->sleep = timeout + jiffies; 1000 drive->sleeping = 1; 1001} 1002 1003EXPORT_SYMBOL(ide_stall_queue); 1004 1005#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) 1006 1007/** 1008 * choose_drive - select a drive to service 1009 * @hwgroup: hardware group to select on 1010 * 1011 * choose_drive() selects the next drive which will be serviced. 1012 * This is necessary because the IDE layer can't issue commands 1013 * to both drives on the same cable, unlike SCSI. 1014 */ 1015 1016static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) 1017{ 1018 ide_drive_t *drive, *best; 1019 1020repeat: 1021 best = NULL; 1022 drive = hwgroup->drive; 1023 1024 /* 1025 * drive is doing pre-flush, ordered write, post-flush sequence. even 1026 * though that is 3 requests, it must be seen as a single transaction. 1027 * we must not preempt this drive until that is complete 1028 */ 1029 if (blk_queue_flushing(drive->queue)) { 1030 /* 1031 * small race where queue could get replugged during 1032 * the 3-request flush cycle, just yank the plug since 1033 * we want it to finish asap 1034 */ 1035 blk_remove_plug(drive->queue); 1036 return drive; 1037 } 1038 1039 do { 1040 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) 1041 && !elv_queue_empty(drive->queue)) { 1042 if (!best 1043 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) 1044 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) 1045 { 1046 if (!blk_queue_plugged(drive->queue)) 1047 best = drive; 1048 } 1049 } 1050 } while ((drive = drive->next) != hwgroup->drive); 1051 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { 1052 long t = (signed long)(WAKEUP(best) - jiffies); 1053 if (t >= WAIT_MIN_SLEEP) { 1054 /* 1055 * We *may* have some time to spare, but first let's see if 1056 * someone can potentially benefit from our nice mood today.. 1057 */ 1058 drive = best->next; 1059 do { 1060 if (!drive->sleeping 1061 && time_before(jiffies - best->service_time, WAKEUP(drive)) 1062 && time_before(WAKEUP(drive), jiffies + t)) 1063 { 1064 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); 1065 goto repeat; 1066 } 1067 } while ((drive = drive->next) != best); 1068 } 1069 } 1070 return best; 1071} 1072 1073/* 1074 * Issue a new request to a drive from hwgroup 1075 * Caller must have already done spin_lock_irqsave(&ide_lock, ..); 1076 * 1077 * A hwgroup is a serialized group of IDE interfaces. Usually there is 1078 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) 1079 * may have both interfaces in a single hwgroup to "serialize" access. 1080 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped 1081 * together into one hwgroup for serialized access. 1082 * 1083 * Note also that several hwgroups can end up sharing a single IRQ, 1084 * possibly along with many other devices. This is especially common in 1085 * PCI-based systems with off-board IDE controller cards. 1086 * 1087 * The IDE driver uses the single global ide_lock spinlock to protect 1088 * access to the request queues, and to protect the hwgroup->busy flag. 1089 * 1090 * The first thread into the driver for a particular hwgroup sets the 1091 * hwgroup->busy flag to indicate that this hwgroup is now active, 1092 * and then initiates processing of the top request from the request queue. 1093 * 1094 * Other threads attempting entry notice the busy setting, and will simply 1095 * queue their new requests and exit immediately. Note that hwgroup->busy 1096 * remains set even when the driver is merely awaiting the next interrupt. 1097 * Thus, the meaning is "this hwgroup is busy processing a request". 1098 * 1099 * When processing of a request completes, the completing thread or IRQ-handler 1100 * will start the next request from the queue. If no more work remains, 1101 * the driver will clear the hwgroup->busy flag and exit. 1102 * 1103 * The ide_lock (spinlock) is used to protect all access to the 1104 * hwgroup->busy flag, but is otherwise not needed for most processing in 1105 * the driver. This makes the driver much more friendlier to shared IRQs 1106 * than previous designs, while remaining 100% (?) SMP safe and capable. 1107 */ 1108static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) 1109{ 1110 ide_drive_t *drive; 1111 ide_hwif_t *hwif; 1112 struct request *rq; 1113 ide_startstop_t startstop; 1114 int loops = 0; 1115 1116 /* for atari only: POSSIBLY BROKEN HERE(?) */ 1117 ide_get_lock(ide_intr, hwgroup); 1118 1119 /* caller must own ide_lock */ 1120 BUG_ON(!irqs_disabled()); 1121 1122 while (!hwgroup->busy) { 1123 hwgroup->busy = 1; 1124 drive = choose_drive(hwgroup); 1125 if (drive == NULL) { 1126 int sleeping = 0; 1127 unsigned long sleep = 0; /* shut up, gcc */ 1128 hwgroup->rq = NULL; 1129 drive = hwgroup->drive; 1130 do { 1131 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { 1132 sleeping = 1; 1133 sleep = drive->sleep; 1134 } 1135 } while ((drive = drive->next) != hwgroup->drive); 1136 if (sleeping) { 1137 /* 1138 * Take a short snooze, and then wake up this hwgroup again. 1139 * This gives other hwgroups on the same a chance to 1140 * play fairly with us, just in case there are big differences 1141 * in relative throughputs.. don't want to hog the cpu too much. 1142 */ 1143 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) 1144 sleep = jiffies + WAIT_MIN_SLEEP; 1145#if 1 1146 if (timer_pending(&hwgroup->timer)) 1147 printk(KERN_CRIT "ide_set_handler: timer already active\n"); 1148#endif 1149 /* so that ide_timer_expiry knows what to do */ 1150 hwgroup->sleeping = 1; 1151 mod_timer(&hwgroup->timer, sleep); 1152 /* we purposely leave hwgroup->busy==1 1153 * while sleeping */ 1154 } else { 1155 /* Ugly, but how can we sleep for the lock 1156 * otherwise? perhaps from tq_disk? 1157 */ 1158 1159 /* for atari only */ 1160 ide_release_lock(); 1161 hwgroup->busy = 0; 1162 } 1163 1164 /* no more work for this hwgroup (for now) */ 1165 return; 1166 } 1167 again: 1168 hwif = HWIF(drive); 1169 if (hwgroup->hwif->sharing_irq && 1170 hwif != hwgroup->hwif && 1171 hwif->io_ports[IDE_CONTROL_OFFSET]) { 1172 /* set nIEN for previous hwif */ 1173 SELECT_INTERRUPT(drive); 1174 } 1175 hwgroup->hwif = hwif; 1176 hwgroup->drive = drive; 1177 drive->sleeping = 0; 1178 drive->service_start = jiffies; 1179 1180 if (blk_queue_plugged(drive->queue)) { 1181 printk(KERN_ERR "ide: huh? queue was plugged!\n"); 1182 break; 1183 } 1184 1185 /* 1186 * we know that the queue isn't empty, but this can happen 1187 * if the q->prep_rq_fn() decides to kill a request 1188 */ 1189 rq = elv_next_request(drive->queue); 1190 if (!rq) { 1191 hwgroup->busy = 0; 1192 break; 1193 } 1194 1195 /* 1196 * Sanity: don't accept a request that isn't a PM request 1197 * if we are currently power managed. This is very important as 1198 * blk_stop_queue() doesn't prevent the elv_next_request() 1199 * above to return us whatever is in the queue. Since we call 1200 * ide_do_request() ourselves, we end up taking requests while 1201 * the queue is blocked... 1202 * 1203 * We let requests forced at head of queue with ide-preempt 1204 * though. I hope that doesn't happen too much, hopefully not 1205 * unless the subdriver triggers such a thing in its own PM 1206 * state machine. 1207 * 1208 * We count how many times we loop here to make sure we service 1209 * all drives in the hwgroup without looping for ever 1210 */ 1211 if (drive->blocked && !blk_pm_request(rq) && !(rq->flags & REQ_PREEMPT)) { 1212 drive = drive->next ? drive->next : hwgroup->drive; 1213 if (loops++ < 4 && !blk_queue_plugged(drive->queue)) 1214 goto again; 1215 /* We clear busy, there should be no pending ATA command at this point. */ 1216 hwgroup->busy = 0; 1217 break; 1218 } 1219 1220 hwgroup->rq = rq; 1221 1222 /* 1223 * Some systems have trouble with IDE IRQs arriving while 1224 * the driver is still setting things up. So, here we disable 1225 * the IRQ used by this interface while the request is being started. 1226 * This may look bad at first, but pretty much the same thing 1227 * happens anyway when any interrupt comes in, IDE or otherwise 1228 * -- the kernel masks the IRQ while it is being handled. 1229 */ 1230 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1231 disable_irq_nosync(hwif->irq); 1232 spin_unlock(&ide_lock); 1233 local_irq_enable(); 1234 /* allow other IRQs while we start this request */ 1235 startstop = start_request(drive, rq); 1236 spin_lock_irq(&ide_lock); 1237 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1238 enable_irq(hwif->irq); 1239 if (startstop == ide_stopped) 1240 hwgroup->busy = 0; 1241 } 1242} 1243 1244/* 1245 * Passes the stuff to ide_do_request 1246 */ 1247void do_ide_request(request_queue_t *q) 1248{ 1249 ide_drive_t *drive = q->queuedata; 1250 1251 ide_do_request(HWGROUP(drive), IDE_NO_IRQ); 1252} 1253 1254/* 1255 * un-busy the hwgroup etc, and clear any pending DMA status. we want to 1256 * retry the current request in pio mode instead of risking tossing it 1257 * all away 1258 */ 1259static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) 1260{ 1261 ide_hwif_t *hwif = HWIF(drive); 1262 struct request *rq; 1263 ide_startstop_t ret = ide_stopped; 1264 1265 /* 1266 * end current dma transaction 1267 */ 1268 1269 if (error < 0) { 1270 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); 1271 (void)HWIF(drive)->ide_dma_end(drive); 1272 ret = ide_error(drive, "dma timeout error", 1273 hwif->INB(IDE_STATUS_REG)); 1274 } else { 1275 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); 1276 (void) hwif->ide_dma_timeout(drive); 1277 } 1278 1279 /* 1280 * disable dma for now, but remember that we did so because of 1281 * a timeout -- we'll reenable after we finish this next request 1282 * (or rather the first chunk of it) in pio. 1283 */ 1284 drive->retry_pio++; 1285 drive->state = DMA_PIO_RETRY; 1286 (void) hwif->ide_dma_off_quietly(drive); 1287 1288 /* 1289 * un-busy drive etc (hwgroup->busy is cleared on return) and 1290 * make sure request is sane 1291 */ 1292 rq = HWGROUP(drive)->rq; 1293 HWGROUP(drive)->rq = NULL; 1294 1295 rq->errors = 0; 1296 1297 if (!rq->bio) 1298 goto out; 1299 1300 rq->sector = rq->bio->bi_sector; 1301 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; 1302 rq->hard_cur_sectors = rq->current_nr_sectors; 1303 rq->buffer = bio_data(rq->bio); 1304out: 1305 return ret; 1306} 1307 1308/** 1309 * ide_timer_expiry - handle lack of an IDE interrupt 1310 * @data: timer callback magic (hwgroup) 1311 * 1312 * An IDE command has timed out before the expected drive return 1313 * occurred. At this point we attempt to clean up the current 1314 * mess. If the current handler includes an expiry handler then 1315 * we invoke the expiry handler, and providing it is happy the 1316 * work is done. If that fails we apply generic recovery rules 1317 * invoking the handler and checking the drive DMA status. We 1318 * have an excessively incestuous relationship with the DMA 1319 * logic that wants cleaning up. 1320 */ 1321 1322void ide_timer_expiry (unsigned long data) 1323{ 1324 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; 1325 ide_handler_t *handler; 1326 ide_expiry_t *expiry; 1327 unsigned long flags; 1328 unsigned long wait = -1; 1329 1330 spin_lock_irqsave(&ide_lock, flags); 1331 1332 if ((handler = hwgroup->handler) == NULL) { 1333 /* 1334 * Either a marginal timeout occurred 1335 * (got the interrupt just as timer expired), 1336 * or we were "sleeping" to give other devices a chance. 1337 * Either way, we don't really want to complain about anything. 1338 */ 1339 if (hwgroup->sleeping) { 1340 hwgroup->sleeping = 0; 1341 hwgroup->busy = 0; 1342 } 1343 } else { 1344 ide_drive_t *drive = hwgroup->drive; 1345 if (!drive) { 1346 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); 1347 hwgroup->handler = NULL; 1348 } else { 1349 ide_hwif_t *hwif; 1350 ide_startstop_t startstop = ide_stopped; 1351 if (!hwgroup->busy) { 1352 hwgroup->busy = 1; /* paranoia */ 1353 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); 1354 } 1355 if ((expiry = hwgroup->expiry) != NULL) { 1356 /* continue */ 1357 if ((wait = expiry(drive)) > 0) { 1358 /* reset timer */ 1359 hwgroup->timer.expires = jiffies + wait; 1360 add_timer(&hwgroup->timer); 1361 spin_unlock_irqrestore(&ide_lock, flags); 1362 return; 1363 } 1364 } 1365 hwgroup->handler = NULL; 1366 /* 1367 * We need to simulate a real interrupt when invoking 1368 * the handler() function, which means we need to 1369 * globally mask the specific IRQ: 1370 */ 1371 spin_unlock(&ide_lock); 1372 hwif = HWIF(drive); 1373#if DISABLE_IRQ_NOSYNC 1374 disable_irq_nosync(hwif->irq); 1375#else 1376 /* disable_irq_nosync ?? */ 1377 disable_irq(hwif->irq); 1378#endif /* DISABLE_IRQ_NOSYNC */ 1379 /* local CPU only, 1380 * as if we were handling an interrupt */ 1381 local_irq_disable(); 1382 if (hwgroup->polling) { 1383 startstop = handler(drive); 1384 } else if (drive_is_ready(drive)) { 1385 if (drive->waiting_for_dma) 1386 (void) hwgroup->hwif->ide_dma_lostirq(drive); 1387 (void)ide_ack_intr(hwif); 1388 printk(KERN_WARNING "%s: lost interrupt\n", drive->name); 1389 startstop = handler(drive); 1390 } else { 1391 if (drive->waiting_for_dma) { 1392 startstop = ide_dma_timeout_retry(drive, wait); 1393 } else 1394 startstop = 1395 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG)); 1396 } 1397 drive->service_time = jiffies - drive->service_start; 1398 spin_lock_irq(&ide_lock); 1399 enable_irq(hwif->irq); 1400 if (startstop == ide_stopped) 1401 hwgroup->busy = 0; 1402 } 1403 } 1404 ide_do_request(hwgroup, IDE_NO_IRQ); 1405 spin_unlock_irqrestore(&ide_lock, flags); 1406} 1407 1408/** 1409 * unexpected_intr - handle an unexpected IDE interrupt 1410 * @irq: interrupt line 1411 * @hwgroup: hwgroup being processed 1412 * 1413 * There's nothing really useful we can do with an unexpected interrupt, 1414 * other than reading the status register (to clear it), and logging it. 1415 * There should be no way that an irq can happen before we're ready for it, 1416 * so we needn't worry much about losing an "important" interrupt here. 1417 * 1418 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever 1419 * the drive enters "idle", "standby", or "sleep" mode, so if the status 1420 * looks "good", we just ignore the interrupt completely. 1421 * 1422 * This routine assumes __cli() is in effect when called. 1423 * 1424 * If an unexpected interrupt happens on irq15 while we are handling irq14 1425 * and if the two interfaces are "serialized" (CMD640), then it looks like 1426 * we could screw up by interfering with a new request being set up for 1427 * irq15. 1428 * 1429 * In reality, this is a non-issue. The new command is not sent unless 1430 * the drive is ready to accept one, in which case we know the drive is 1431 * not trying to interrupt us. And ide_set_handler() is always invoked 1432 * before completing the issuance of any new drive command, so we will not 1433 * be accidentally invoked as a result of any valid command completion 1434 * interrupt. 1435 * 1436 * Note that we must walk the entire hwgroup here. We know which hwif 1437 * is doing the current command, but we don't know which hwif burped 1438 * mysteriously. 1439 */ 1440 1441static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) 1442{ 1443 u8 stat; 1444 ide_hwif_t *hwif = hwgroup->hwif; 1445 1446 /* 1447 * handle the unexpected interrupt 1448 */ 1449 do { 1450 if (hwif->irq == irq) { 1451 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1452 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { 1453 /* Try to not flood the console with msgs */ 1454 static unsigned long last_msgtime, count; 1455 ++count; 1456 if (time_after(jiffies, last_msgtime + HZ)) { 1457 last_msgtime = jiffies; 1458 printk(KERN_ERR "%s%s: unexpected interrupt, " 1459 "status=0x%02x, count=%ld\n", 1460 hwif->name, 1461 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); 1462 } 1463 } 1464 } 1465 } while ((hwif = hwif->next) != hwgroup->hwif); 1466} 1467 1468/** 1469 * ide_intr - default IDE interrupt handler 1470 * @irq: interrupt number 1471 * @dev_id: hwif group 1472 * @regs: unused weirdness from the kernel irq layer 1473 * 1474 * This is the default IRQ handler for the IDE layer. You should 1475 * not need to override it. If you do be aware it is subtle in 1476 * places 1477 * 1478 * hwgroup->hwif is the interface in the group currently performing 1479 * a command. hwgroup->drive is the drive and hwgroup->handler is 1480 * the IRQ handler to call. As we issue a command the handlers 1481 * step through multiple states, reassigning the handler to the 1482 * next step in the process. Unlike a smart SCSI controller IDE 1483 * expects the main processor to sequence the various transfer 1484 * stages. We also manage a poll timer to catch up with most 1485 * timeout situations. There are still a few where the handlers 1486 * don't ever decide to give up. 1487 * 1488 * The handler eventually returns ide_stopped to indicate the 1489 * request completed. At this point we issue the next request 1490 * on the hwgroup and the process begins again. 1491 */ 1492 1493irqreturn_t ide_intr (int irq, void *dev_id, struct pt_regs *regs) 1494{ 1495 unsigned long flags; 1496 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; 1497 ide_hwif_t *hwif; 1498 ide_drive_t *drive; 1499 ide_handler_t *handler; 1500 ide_startstop_t startstop; 1501 1502 spin_lock_irqsave(&ide_lock, flags); 1503 hwif = hwgroup->hwif; 1504 1505 if (!ide_ack_intr(hwif)) { 1506 spin_unlock_irqrestore(&ide_lock, flags); 1507 return IRQ_NONE; 1508 } 1509 1510 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { 1511 /* 1512 * Not expecting an interrupt from this drive. 1513 * That means this could be: 1514 * (1) an interrupt from another PCI device 1515 * sharing the same PCI INT# as us. 1516 * or (2) a drive just entered sleep or standby mode, 1517 * and is interrupting to let us know. 1518 * or (3) a spurious interrupt of unknown origin. 1519 * 1520 * For PCI, we cannot tell the difference, 1521 * so in that case we just ignore it and hope it goes away. 1522 * 1523 * FIXME: unexpected_intr should be hwif-> then we can 1524 * remove all the ifdef PCI crap 1525 */ 1526#ifdef CONFIG_BLK_DEV_IDEPCI 1527 if (hwif->pci_dev && !hwif->pci_dev->vendor) 1528#endif /* CONFIG_BLK_DEV_IDEPCI */ 1529 { 1530 /* 1531 * Probably not a shared PCI interrupt, 1532 * so we can safely try to do something about it: 1533 */ 1534 unexpected_intr(irq, hwgroup); 1535#ifdef CONFIG_BLK_DEV_IDEPCI 1536 } else { 1537 /* 1538 * Whack the status register, just in case 1539 * we have a leftover pending IRQ. 1540 */ 1541 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1542#endif /* CONFIG_BLK_DEV_IDEPCI */ 1543 } 1544 spin_unlock_irqrestore(&ide_lock, flags); 1545 return IRQ_NONE; 1546 } 1547 drive = hwgroup->drive; 1548 if (!drive) { 1549 /* 1550 * This should NEVER happen, and there isn't much 1551 * we could do about it here. 1552 * 1553 * [Note - this can occur if the drive is hot unplugged] 1554 */ 1555 spin_unlock_irqrestore(&ide_lock, flags); 1556 return IRQ_HANDLED; 1557 } 1558 if (!drive_is_ready(drive)) { 1559 /* 1560 * This happens regularly when we share a PCI IRQ with 1561 * another device. Unfortunately, it can also happen 1562 * with some buggy drives that trigger the IRQ before 1563 * their status register is up to date. Hopefully we have 1564 * enough advance overhead that the latter isn't a problem. 1565 */ 1566 spin_unlock_irqrestore(&ide_lock, flags); 1567 return IRQ_NONE; 1568 } 1569 if (!hwgroup->busy) { 1570 hwgroup->busy = 1; /* paranoia */ 1571 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); 1572 } 1573 hwgroup->handler = NULL; 1574 del_timer(&hwgroup->timer); 1575 spin_unlock(&ide_lock); 1576 1577 if (drive->unmask) 1578 local_irq_enable(); 1579 /* service this interrupt, may set handler for next interrupt */ 1580 startstop = handler(drive); 1581 spin_lock_irq(&ide_lock); 1582 1583 /* 1584 * Note that handler() may have set things up for another 1585 * interrupt to occur soon, but it cannot happen until 1586 * we exit from this routine, because it will be the 1587 * same irq as is currently being serviced here, and Linux 1588 * won't allow another of the same (on any CPU) until we return. 1589 */ 1590 drive->service_time = jiffies - drive->service_start; 1591 if (startstop == ide_stopped) { 1592 if (hwgroup->handler == NULL) { /* paranoia */ 1593 hwgroup->busy = 0; 1594 ide_do_request(hwgroup, hwif->irq); 1595 } else { 1596 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " 1597 "on exit\n", drive->name); 1598 } 1599 } 1600 spin_unlock_irqrestore(&ide_lock, flags); 1601 return IRQ_HANDLED; 1602} 1603 1604/** 1605 * ide_init_drive_cmd - initialize a drive command request 1606 * @rq: request object 1607 * 1608 * Initialize a request before we fill it in and send it down to 1609 * ide_do_drive_cmd. Commands must be set up by this function. Right 1610 * now it doesn't do a lot, but if that changes abusers will have a 1611 * nasty suprise. 1612 */ 1613 1614void ide_init_drive_cmd (struct request *rq) 1615{ 1616 memset(rq, 0, sizeof(*rq)); 1617 rq->flags = REQ_DRIVE_CMD; 1618 rq->ref_count = 1; 1619} 1620 1621EXPORT_SYMBOL(ide_init_drive_cmd); 1622 1623/** 1624 * ide_do_drive_cmd - issue IDE special command 1625 * @drive: device to issue command 1626 * @rq: request to issue 1627 * @action: action for processing 1628 * 1629 * This function issues a special IDE device request 1630 * onto the request queue. 1631 * 1632 * If action is ide_wait, then the rq is queued at the end of the 1633 * request queue, and the function sleeps until it has been processed. 1634 * This is for use when invoked from an ioctl handler. 1635 * 1636 * If action is ide_preempt, then the rq is queued at the head of 1637 * the request queue, displacing the currently-being-processed 1638 * request and this function returns immediately without waiting 1639 * for the new rq to be completed. This is VERY DANGEROUS, and is 1640 * intended for careful use by the ATAPI tape/cdrom driver code. 1641 * 1642 * If action is ide_end, then the rq is queued at the end of the 1643 * request queue, and the function returns immediately without waiting 1644 * for the new rq to be completed. This is again intended for careful 1645 * use by the ATAPI tape/cdrom driver code. 1646 */ 1647 1648int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) 1649{ 1650 unsigned long flags; 1651 ide_hwgroup_t *hwgroup = HWGROUP(drive); 1652 DECLARE_COMPLETION(wait); 1653 int where = ELEVATOR_INSERT_BACK, err; 1654 int must_wait = (action == ide_wait || action == ide_head_wait); 1655 1656 rq->errors = 0; 1657 rq->rq_status = RQ_ACTIVE; 1658 1659 /* 1660 * we need to hold an extra reference to request for safe inspection 1661 * after completion 1662 */ 1663 if (must_wait) { 1664 rq->ref_count++; 1665 rq->waiting = &wait; 1666 rq->end_io = blk_end_sync_rq; 1667 } 1668 1669 spin_lock_irqsave(&ide_lock, flags); 1670 if (action == ide_preempt) 1671 hwgroup->rq = NULL; 1672 if (action == ide_preempt || action == ide_head_wait) { 1673 where = ELEVATOR_INSERT_FRONT; 1674 rq->flags |= REQ_PREEMPT; 1675 } 1676 __elv_add_request(drive->queue, rq, where, 0); 1677 ide_do_request(hwgroup, IDE_NO_IRQ); 1678 spin_unlock_irqrestore(&ide_lock, flags); 1679 1680 err = 0; 1681 if (must_wait) { 1682 wait_for_completion(&wait); 1683 rq->waiting = NULL; 1684 if (rq->errors) 1685 err = -EIO; 1686 1687 blk_put_request(rq); 1688 } 1689 1690 return err; 1691} 1692 1693EXPORT_SYMBOL(ide_do_drive_cmd); 1694