ide-io.c revision 7299a3918442dc9a5abb71b9f65b1dd17637c8c0
1/* 2 * IDE I/O functions 3 * 4 * Basic PIO and command management functionality. 5 * 6 * This code was split off from ide.c. See ide.c for history and original 7 * copyrights. 8 * 9 * This program is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by the 11 * Free Software Foundation; either version 2, or (at your option) any 12 * later version. 13 * 14 * This program is distributed in the hope that it will be useful, but 15 * WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * General Public License for more details. 18 * 19 * For the avoidance of doubt the "preferred form" of this code is one which 20 * is in an open non patent encumbered format. Where cryptographic key signing 21 * forms part of the process of creating an executable the information 22 * including keys needed to generate an equivalently functional executable 23 * are deemed to be part of the source code. 24 */ 25 26 27#include <linux/module.h> 28#include <linux/types.h> 29#include <linux/string.h> 30#include <linux/kernel.h> 31#include <linux/timer.h> 32#include <linux/mm.h> 33#include <linux/interrupt.h> 34#include <linux/major.h> 35#include <linux/errno.h> 36#include <linux/genhd.h> 37#include <linux/blkpg.h> 38#include <linux/slab.h> 39#include <linux/init.h> 40#include <linux/pci.h> 41#include <linux/delay.h> 42#include <linux/ide.h> 43#include <linux/completion.h> 44#include <linux/reboot.h> 45#include <linux/cdrom.h> 46#include <linux/seq_file.h> 47#include <linux/device.h> 48#include <linux/kmod.h> 49#include <linux/scatterlist.h> 50#include <linux/bitops.h> 51 52#include <asm/byteorder.h> 53#include <asm/irq.h> 54#include <asm/uaccess.h> 55#include <asm/io.h> 56 57static int __ide_end_request(ide_drive_t *drive, struct request *rq, 58 int uptodate, unsigned int nr_bytes, int dequeue) 59{ 60 int ret = 1; 61 62 /* 63 * if failfast is set on a request, override number of sectors and 64 * complete the whole request right now 65 */ 66 if (blk_noretry_request(rq) && end_io_error(uptodate)) 67 nr_bytes = rq->hard_nr_sectors << 9; 68 69 if (!blk_fs_request(rq) && end_io_error(uptodate) && !rq->errors) 70 rq->errors = -EIO; 71 72 /* 73 * decide whether to reenable DMA -- 3 is a random magic for now, 74 * if we DMA timeout more than 3 times, just stay in PIO 75 */ 76 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) { 77 drive->state = 0; 78 HWGROUP(drive)->hwif->ide_dma_on(drive); 79 } 80 81 if (!end_that_request_chunk(rq, uptodate, nr_bytes)) { 82 add_disk_randomness(rq->rq_disk); 83 if (dequeue) { 84 if (!list_empty(&rq->queuelist)) 85 blkdev_dequeue_request(rq); 86 HWGROUP(drive)->rq = NULL; 87 } 88 end_that_request_last(rq, uptodate); 89 ret = 0; 90 } 91 92 return ret; 93} 94 95/** 96 * ide_end_request - complete an IDE I/O 97 * @drive: IDE device for the I/O 98 * @uptodate: 99 * @nr_sectors: number of sectors completed 100 * 101 * This is our end_request wrapper function. We complete the I/O 102 * update random number input and dequeue the request, which if 103 * it was tagged may be out of order. 104 */ 105 106int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors) 107{ 108 unsigned int nr_bytes = nr_sectors << 9; 109 struct request *rq; 110 unsigned long flags; 111 int ret = 1; 112 113 /* 114 * room for locking improvements here, the calls below don't 115 * need the queue lock held at all 116 */ 117 spin_lock_irqsave(&ide_lock, flags); 118 rq = HWGROUP(drive)->rq; 119 120 if (!nr_bytes) { 121 if (blk_pc_request(rq)) 122 nr_bytes = rq->data_len; 123 else 124 nr_bytes = rq->hard_cur_sectors << 9; 125 } 126 127 ret = __ide_end_request(drive, rq, uptodate, nr_bytes, 1); 128 129 spin_unlock_irqrestore(&ide_lock, flags); 130 return ret; 131} 132EXPORT_SYMBOL(ide_end_request); 133 134/* 135 * Power Management state machine. This one is rather trivial for now, 136 * we should probably add more, like switching back to PIO on suspend 137 * to help some BIOSes, re-do the door locking on resume, etc... 138 */ 139 140enum { 141 ide_pm_flush_cache = ide_pm_state_start_suspend, 142 idedisk_pm_standby, 143 144 idedisk_pm_restore_pio = ide_pm_state_start_resume, 145 idedisk_pm_idle, 146 ide_pm_restore_dma, 147}; 148 149static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error) 150{ 151 struct request_pm_state *pm = rq->data; 152 153 if (drive->media != ide_disk) 154 return; 155 156 switch (pm->pm_step) { 157 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */ 158 if (pm->pm_state == PM_EVENT_FREEZE) 159 pm->pm_step = ide_pm_state_completed; 160 else 161 pm->pm_step = idedisk_pm_standby; 162 break; 163 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */ 164 pm->pm_step = ide_pm_state_completed; 165 break; 166 case idedisk_pm_restore_pio: /* Resume step 1 complete */ 167 pm->pm_step = idedisk_pm_idle; 168 break; 169 case idedisk_pm_idle: /* Resume step 2 (idle) complete */ 170 pm->pm_step = ide_pm_restore_dma; 171 break; 172 } 173} 174 175static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq) 176{ 177 struct request_pm_state *pm = rq->data; 178 ide_task_t *args = rq->special; 179 180 memset(args, 0, sizeof(*args)); 181 182 switch (pm->pm_step) { 183 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */ 184 if (drive->media != ide_disk) 185 break; 186 /* Not supported? Switch to next step now. */ 187 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) { 188 ide_complete_power_step(drive, rq, 0, 0); 189 return ide_stopped; 190 } 191 if (ide_id_has_flush_cache_ext(drive->id)) 192 args->tf.command = WIN_FLUSH_CACHE_EXT; 193 else 194 args->tf.command = WIN_FLUSH_CACHE; 195 goto out_do_tf; 196 197 case idedisk_pm_standby: /* Suspend step 2 (standby) */ 198 args->tf.command = WIN_STANDBYNOW1; 199 goto out_do_tf; 200 201 case idedisk_pm_restore_pio: /* Resume step 1 (restore PIO) */ 202 ide_set_max_pio(drive); 203 /* 204 * skip idedisk_pm_idle for ATAPI devices 205 */ 206 if (drive->media != ide_disk) 207 pm->pm_step = ide_pm_restore_dma; 208 else 209 ide_complete_power_step(drive, rq, 0, 0); 210 return ide_stopped; 211 212 case idedisk_pm_idle: /* Resume step 2 (idle) */ 213 args->tf.command = WIN_IDLEIMMEDIATE; 214 goto out_do_tf; 215 216 case ide_pm_restore_dma: /* Resume step 3 (restore DMA) */ 217 /* 218 * Right now, all we do is call ide_set_dma(drive), 219 * we could be smarter and check for current xfer_speed 220 * in struct drive etc... 221 */ 222 if (drive->hwif->ide_dma_on == NULL) 223 break; 224 drive->hwif->dma_off_quietly(drive); 225 /* 226 * TODO: respect ->using_dma setting 227 */ 228 ide_set_dma(drive); 229 break; 230 } 231 pm->pm_step = ide_pm_state_completed; 232 return ide_stopped; 233 234out_do_tf: 235 args->tf_flags = IDE_TFLAG_OUT_TF | IDE_TFLAG_OUT_DEVICE; 236 args->command_type = IDE_DRIVE_TASK_NO_DATA; 237 args->handler = task_no_data_intr; 238 return do_rw_taskfile(drive, args); 239} 240 241/** 242 * ide_end_dequeued_request - complete an IDE I/O 243 * @drive: IDE device for the I/O 244 * @uptodate: 245 * @nr_sectors: number of sectors completed 246 * 247 * Complete an I/O that is no longer on the request queue. This 248 * typically occurs when we pull the request and issue a REQUEST_SENSE. 249 * We must still finish the old request but we must not tamper with the 250 * queue in the meantime. 251 * 252 * NOTE: This path does not handle barrier, but barrier is not supported 253 * on ide-cd anyway. 254 */ 255 256int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq, 257 int uptodate, int nr_sectors) 258{ 259 unsigned long flags; 260 int ret; 261 262 spin_lock_irqsave(&ide_lock, flags); 263 BUG_ON(!blk_rq_started(rq)); 264 ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0); 265 spin_unlock_irqrestore(&ide_lock, flags); 266 267 return ret; 268} 269EXPORT_SYMBOL_GPL(ide_end_dequeued_request); 270 271 272/** 273 * ide_complete_pm_request - end the current Power Management request 274 * @drive: target drive 275 * @rq: request 276 * 277 * This function cleans up the current PM request and stops the queue 278 * if necessary. 279 */ 280static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq) 281{ 282 unsigned long flags; 283 284#ifdef DEBUG_PM 285 printk("%s: completing PM request, %s\n", drive->name, 286 blk_pm_suspend_request(rq) ? "suspend" : "resume"); 287#endif 288 spin_lock_irqsave(&ide_lock, flags); 289 if (blk_pm_suspend_request(rq)) { 290 blk_stop_queue(drive->queue); 291 } else { 292 drive->blocked = 0; 293 blk_start_queue(drive->queue); 294 } 295 blkdev_dequeue_request(rq); 296 HWGROUP(drive)->rq = NULL; 297 end_that_request_last(rq, 1); 298 spin_unlock_irqrestore(&ide_lock, flags); 299} 300 301/** 302 * ide_end_drive_cmd - end an explicit drive command 303 * @drive: command 304 * @stat: status bits 305 * @err: error bits 306 * 307 * Clean up after success/failure of an explicit drive command. 308 * These get thrown onto the queue so they are synchronized with 309 * real I/O operations on the drive. 310 * 311 * In LBA48 mode we have to read the register set twice to get 312 * all the extra information out. 313 */ 314 315void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) 316{ 317 ide_hwif_t *hwif = HWIF(drive); 318 unsigned long flags; 319 struct request *rq; 320 321 spin_lock_irqsave(&ide_lock, flags); 322 rq = HWGROUP(drive)->rq; 323 spin_unlock_irqrestore(&ide_lock, flags); 324 325 if (rq->cmd_type == REQ_TYPE_ATA_CMD) { 326 u8 *args = (u8 *) rq->buffer; 327 if (rq->errors == 0) 328 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 329 330 if (args) { 331 args[0] = stat; 332 args[1] = err; 333 args[2] = hwif->INB(IDE_NSECTOR_REG); 334 } 335 } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 336 ide_task_t *args = (ide_task_t *) rq->special; 337 if (rq->errors == 0) 338 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 339 340 if (args) { 341 struct ide_taskfile *tf = &args->tf; 342 343 if (args->tf_in_flags.b.data) { 344 u16 data = hwif->INW(IDE_DATA_REG); 345 346 tf->data = data & 0xff; 347 tf->hob_data = (data >> 8) & 0xff; 348 } 349 tf->error = err; 350 /* be sure we're looking at the low order bits */ 351 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG); 352 tf->nsect = hwif->INB(IDE_NSECTOR_REG); 353 tf->lbal = hwif->INB(IDE_SECTOR_REG); 354 tf->lbam = hwif->INB(IDE_LCYL_REG); 355 tf->lbah = hwif->INB(IDE_HCYL_REG); 356 tf->device = hwif->INB(IDE_SELECT_REG); 357 tf->status = stat; 358 359 if (args->tf_flags & IDE_TFLAG_LBA48) { 360 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG); 361 tf->hob_feature = hwif->INB(IDE_FEATURE_REG); 362 tf->hob_nsect = hwif->INB(IDE_NSECTOR_REG); 363 tf->hob_lbal = hwif->INB(IDE_SECTOR_REG); 364 tf->hob_lbam = hwif->INB(IDE_LCYL_REG); 365 tf->hob_lbah = hwif->INB(IDE_HCYL_REG); 366 } 367 } 368 } else if (blk_pm_request(rq)) { 369 struct request_pm_state *pm = rq->data; 370#ifdef DEBUG_PM 371 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n", 372 drive->name, rq->pm->pm_step, stat, err); 373#endif 374 ide_complete_power_step(drive, rq, stat, err); 375 if (pm->pm_step == ide_pm_state_completed) 376 ide_complete_pm_request(drive, rq); 377 return; 378 } 379 380 spin_lock_irqsave(&ide_lock, flags); 381 blkdev_dequeue_request(rq); 382 HWGROUP(drive)->rq = NULL; 383 rq->errors = err; 384 end_that_request_last(rq, !rq->errors); 385 spin_unlock_irqrestore(&ide_lock, flags); 386} 387 388EXPORT_SYMBOL(ide_end_drive_cmd); 389 390/** 391 * try_to_flush_leftover_data - flush junk 392 * @drive: drive to flush 393 * 394 * try_to_flush_leftover_data() is invoked in response to a drive 395 * unexpectedly having its DRQ_STAT bit set. As an alternative to 396 * resetting the drive, this routine tries to clear the condition 397 * by read a sector's worth of data from the drive. Of course, 398 * this may not help if the drive is *waiting* for data from *us*. 399 */ 400static void try_to_flush_leftover_data (ide_drive_t *drive) 401{ 402 int i = (drive->mult_count ? drive->mult_count : 1) * SECTOR_WORDS; 403 404 if (drive->media != ide_disk) 405 return; 406 while (i > 0) { 407 u32 buffer[16]; 408 u32 wcount = (i > 16) ? 16 : i; 409 410 i -= wcount; 411 HWIF(drive)->ata_input_data(drive, buffer, wcount); 412 } 413} 414 415static void ide_kill_rq(ide_drive_t *drive, struct request *rq) 416{ 417 if (rq->rq_disk) { 418 ide_driver_t *drv; 419 420 drv = *(ide_driver_t **)rq->rq_disk->private_data; 421 drv->end_request(drive, 0, 0); 422 } else 423 ide_end_request(drive, 0, 0); 424} 425 426static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 427{ 428 ide_hwif_t *hwif = drive->hwif; 429 430 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 431 /* other bits are useless when BUSY */ 432 rq->errors |= ERROR_RESET; 433 } else if (stat & ERR_STAT) { 434 /* err has different meaning on cdrom and tape */ 435 if (err == ABRT_ERR) { 436 if (drive->select.b.lba && 437 /* some newer drives don't support WIN_SPECIFY */ 438 hwif->INB(IDE_COMMAND_REG) == WIN_SPECIFY) 439 return ide_stopped; 440 } else if ((err & BAD_CRC) == BAD_CRC) { 441 /* UDMA crc error, just retry the operation */ 442 drive->crc_count++; 443 } else if (err & (BBD_ERR | ECC_ERR)) { 444 /* retries won't help these */ 445 rq->errors = ERROR_MAX; 446 } else if (err & TRK0_ERR) { 447 /* help it find track zero */ 448 rq->errors |= ERROR_RECAL; 449 } 450 } 451 452 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ && 453 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) 454 try_to_flush_leftover_data(drive); 455 456 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) { 457 ide_kill_rq(drive, rq); 458 return ide_stopped; 459 } 460 461 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 462 rq->errors |= ERROR_RESET; 463 464 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 465 ++rq->errors; 466 return ide_do_reset(drive); 467 } 468 469 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) 470 drive->special.b.recalibrate = 1; 471 472 ++rq->errors; 473 474 return ide_stopped; 475} 476 477static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 478{ 479 ide_hwif_t *hwif = drive->hwif; 480 481 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 482 /* other bits are useless when BUSY */ 483 rq->errors |= ERROR_RESET; 484 } else { 485 /* add decoding error stuff */ 486 } 487 488 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 489 /* force an abort */ 490 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 491 492 if (rq->errors >= ERROR_MAX) { 493 ide_kill_rq(drive, rq); 494 } else { 495 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 496 ++rq->errors; 497 return ide_do_reset(drive); 498 } 499 ++rq->errors; 500 } 501 502 return ide_stopped; 503} 504 505ide_startstop_t 506__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 507{ 508 if (drive->media == ide_disk) 509 return ide_ata_error(drive, rq, stat, err); 510 return ide_atapi_error(drive, rq, stat, err); 511} 512 513EXPORT_SYMBOL_GPL(__ide_error); 514 515/** 516 * ide_error - handle an error on the IDE 517 * @drive: drive the error occurred on 518 * @msg: message to report 519 * @stat: status bits 520 * 521 * ide_error() takes action based on the error returned by the drive. 522 * For normal I/O that may well include retries. We deal with 523 * both new-style (taskfile) and old style command handling here. 524 * In the case of taskfile command handling there is work left to 525 * do 526 */ 527 528ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) 529{ 530 struct request *rq; 531 u8 err; 532 533 err = ide_dump_status(drive, msg, stat); 534 535 if ((rq = HWGROUP(drive)->rq) == NULL) 536 return ide_stopped; 537 538 /* retry only "normal" I/O: */ 539 if (!blk_fs_request(rq)) { 540 rq->errors = 1; 541 ide_end_drive_cmd(drive, stat, err); 542 return ide_stopped; 543 } 544 545 if (rq->rq_disk) { 546 ide_driver_t *drv; 547 548 drv = *(ide_driver_t **)rq->rq_disk->private_data; 549 return drv->error(drive, rq, stat, err); 550 } else 551 return __ide_error(drive, rq, stat, err); 552} 553 554EXPORT_SYMBOL_GPL(ide_error); 555 556ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) 557{ 558 if (drive->media != ide_disk) 559 rq->errors |= ERROR_RESET; 560 561 ide_kill_rq(drive, rq); 562 563 return ide_stopped; 564} 565 566EXPORT_SYMBOL_GPL(__ide_abort); 567 568/** 569 * ide_abort - abort pending IDE operations 570 * @drive: drive the error occurred on 571 * @msg: message to report 572 * 573 * ide_abort kills and cleans up when we are about to do a 574 * host initiated reset on active commands. Longer term we 575 * want handlers to have sensible abort handling themselves 576 * 577 * This differs fundamentally from ide_error because in 578 * this case the command is doing just fine when we 579 * blow it away. 580 */ 581 582ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) 583{ 584 struct request *rq; 585 586 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) 587 return ide_stopped; 588 589 /* retry only "normal" I/O: */ 590 if (!blk_fs_request(rq)) { 591 rq->errors = 1; 592 ide_end_drive_cmd(drive, BUSY_STAT, 0); 593 return ide_stopped; 594 } 595 596 if (rq->rq_disk) { 597 ide_driver_t *drv; 598 599 drv = *(ide_driver_t **)rq->rq_disk->private_data; 600 return drv->abort(drive, rq); 601 } else 602 return __ide_abort(drive, rq); 603} 604 605/** 606 * drive_cmd_intr - drive command completion interrupt 607 * @drive: drive the completion interrupt occurred on 608 * 609 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD. 610 * We do any necessary data reading and then wait for the drive to 611 * go non busy. At that point we may read the error data and complete 612 * the request 613 */ 614 615static ide_startstop_t drive_cmd_intr (ide_drive_t *drive) 616{ 617 struct request *rq = HWGROUP(drive)->rq; 618 ide_hwif_t *hwif = HWIF(drive); 619 u8 *args = (u8 *) rq->buffer; 620 u8 stat = hwif->INB(IDE_STATUS_REG); 621 int retries = 10; 622 623 local_irq_enable_in_hardirq(); 624 if (rq->cmd_type == REQ_TYPE_ATA_CMD && 625 (stat & DRQ_STAT) && args && args[3]) { 626 u8 io_32bit = drive->io_32bit; 627 drive->io_32bit = 0; 628 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS); 629 drive->io_32bit = io_32bit; 630 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--) 631 udelay(100); 632 } 633 634 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) 635 return ide_error(drive, "drive_cmd", stat); 636 /* calls ide_end_drive_cmd */ 637 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG)); 638 return ide_stopped; 639} 640 641static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task) 642{ 643 task->tf.nsect = drive->sect; 644 task->tf.lbal = drive->sect; 645 task->tf.lbam = drive->cyl; 646 task->tf.lbah = drive->cyl >> 8; 647 task->tf.device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA; 648 task->tf.command = WIN_SPECIFY; 649 650 task->handler = &set_geometry_intr; 651} 652 653static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task) 654{ 655 task->tf.nsect = drive->sect; 656 task->tf.command = WIN_RESTORE; 657 658 task->handler = &recal_intr; 659} 660 661static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task) 662{ 663 task->tf.nsect = drive->mult_req; 664 task->tf.command = WIN_SETMULT; 665 666 task->handler = &set_multmode_intr; 667} 668 669static ide_startstop_t ide_disk_special(ide_drive_t *drive) 670{ 671 special_t *s = &drive->special; 672 ide_task_t args; 673 674 memset(&args, 0, sizeof(ide_task_t)); 675 args.command_type = IDE_DRIVE_TASK_NO_DATA; 676 677 if (s->b.set_geometry) { 678 s->b.set_geometry = 0; 679 ide_init_specify_cmd(drive, &args); 680 } else if (s->b.recalibrate) { 681 s->b.recalibrate = 0; 682 ide_init_restore_cmd(drive, &args); 683 } else if (s->b.set_multmode) { 684 s->b.set_multmode = 0; 685 if (drive->mult_req > drive->id->max_multsect) 686 drive->mult_req = drive->id->max_multsect; 687 ide_init_setmult_cmd(drive, &args); 688 } else if (s->all) { 689 int special = s->all; 690 s->all = 0; 691 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); 692 return ide_stopped; 693 } 694 695 args.tf_flags = IDE_TFLAG_OUT_TF | IDE_TFLAG_OUT_DEVICE; 696 697 do_rw_taskfile(drive, &args); 698 699 return ide_started; 700} 701 702/* 703 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away 704 */ 705static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio) 706{ 707 switch (req_pio) { 708 case 202: 709 case 201: 710 case 200: 711 case 102: 712 case 101: 713 case 100: 714 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0; 715 case 9: 716 case 8: 717 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0; 718 case 7: 719 case 6: 720 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0; 721 default: 722 return 0; 723 } 724} 725 726/** 727 * do_special - issue some special commands 728 * @drive: drive the command is for 729 * 730 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT 731 * commands to a drive. It used to do much more, but has been scaled 732 * back. 733 */ 734 735static ide_startstop_t do_special (ide_drive_t *drive) 736{ 737 special_t *s = &drive->special; 738 739#ifdef DEBUG 740 printk("%s: do_special: 0x%02x\n", drive->name, s->all); 741#endif 742 if (s->b.set_tune) { 743 ide_hwif_t *hwif = drive->hwif; 744 u8 req_pio = drive->tune_req; 745 746 s->b.set_tune = 0; 747 748 if (set_pio_mode_abuse(drive->hwif, req_pio)) { 749 750 if (hwif->set_pio_mode == NULL) 751 return ide_stopped; 752 753 /* 754 * take ide_lock for drive->[no_]unmask/[no_]io_32bit 755 */ 756 if (req_pio == 8 || req_pio == 9) { 757 unsigned long flags; 758 759 spin_lock_irqsave(&ide_lock, flags); 760 hwif->set_pio_mode(drive, req_pio); 761 spin_unlock_irqrestore(&ide_lock, flags); 762 } else 763 hwif->set_pio_mode(drive, req_pio); 764 } else { 765 int keep_dma = drive->using_dma; 766 767 ide_set_pio(drive, req_pio); 768 769 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) { 770 if (keep_dma) 771 hwif->ide_dma_on(drive); 772 } 773 } 774 775 return ide_stopped; 776 } else { 777 if (drive->media == ide_disk) 778 return ide_disk_special(drive); 779 780 s->all = 0; 781 drive->mult_req = 0; 782 return ide_stopped; 783 } 784} 785 786void ide_map_sg(ide_drive_t *drive, struct request *rq) 787{ 788 ide_hwif_t *hwif = drive->hwif; 789 struct scatterlist *sg = hwif->sg_table; 790 791 if (hwif->sg_mapped) /* needed by ide-scsi */ 792 return; 793 794 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) { 795 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); 796 } else { 797 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); 798 hwif->sg_nents = 1; 799 } 800} 801 802EXPORT_SYMBOL_GPL(ide_map_sg); 803 804void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) 805{ 806 ide_hwif_t *hwif = drive->hwif; 807 808 hwif->nsect = hwif->nleft = rq->nr_sectors; 809 hwif->cursg_ofs = 0; 810 hwif->cursg = NULL; 811} 812 813EXPORT_SYMBOL_GPL(ide_init_sg_cmd); 814 815/** 816 * execute_drive_command - issue special drive command 817 * @drive: the drive to issue the command on 818 * @rq: the request structure holding the command 819 * 820 * execute_drive_cmd() issues a special drive command, usually 821 * initiated by ioctl() from the external hdparm program. The 822 * command can be a drive command, drive task or taskfile 823 * operation. Weirdly you can call it with NULL to wait for 824 * all commands to finish. Don't do this as that is due to change 825 */ 826 827static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, 828 struct request *rq) 829{ 830 ide_hwif_t *hwif = HWIF(drive); 831 u8 *args = rq->buffer; 832 ide_task_t ltask; 833 struct ide_taskfile *tf = <ask.tf; 834 835 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 836 ide_task_t *task = rq->special; 837 838 if (task == NULL) 839 goto done; 840 841 hwif->data_phase = task->data_phase; 842 843 switch (hwif->data_phase) { 844 case TASKFILE_MULTI_OUT: 845 case TASKFILE_OUT: 846 case TASKFILE_MULTI_IN: 847 case TASKFILE_IN: 848 ide_init_sg_cmd(drive, rq); 849 ide_map_sg(drive, rq); 850 default: 851 break; 852 } 853 854 if (task->tf_flags & IDE_TFLAG_FLAGGED) 855 return flagged_taskfile(drive, task); 856 857 return do_rw_taskfile(drive, task); 858 } 859 860 if (args == NULL) 861 goto done; 862 863 memset(<ask, 0, sizeof(ltask)); 864 if (rq->cmd_type == REQ_TYPE_ATA_CMD) { 865#ifdef DEBUG 866 printk("%s: DRIVE_CMD\n", drive->name); 867#endif 868 tf->feature = args[2]; 869 if (args[0] == WIN_SMART) { 870 tf->nsect = args[3]; 871 tf->lbal = args[1]; 872 tf->lbam = 0x4f; 873 tf->lbah = 0xc2; 874 ltask.tf_flags = IDE_TFLAG_OUT_TF; 875 } else { 876 tf->nsect = args[1]; 877 ltask.tf_flags = IDE_TFLAG_OUT_FEATURE | 878 IDE_TFLAG_OUT_NSECT; 879 } 880 } 881 tf->command = args[0]; 882 ide_tf_load(drive, <ask); 883 ide_execute_command(drive, args[0], &drive_cmd_intr, WAIT_WORSTCASE, NULL); 884 return ide_started; 885 886done: 887 /* 888 * NULL is actually a valid way of waiting for 889 * all current requests to be flushed from the queue. 890 */ 891#ifdef DEBUG 892 printk("%s: DRIVE_CMD (null)\n", drive->name); 893#endif 894 ide_end_drive_cmd(drive, 895 hwif->INB(IDE_STATUS_REG), 896 hwif->INB(IDE_ERROR_REG)); 897 return ide_stopped; 898} 899 900static void ide_check_pm_state(ide_drive_t *drive, struct request *rq) 901{ 902 struct request_pm_state *pm = rq->data; 903 904 if (blk_pm_suspend_request(rq) && 905 pm->pm_step == ide_pm_state_start_suspend) 906 /* Mark drive blocked when starting the suspend sequence. */ 907 drive->blocked = 1; 908 else if (blk_pm_resume_request(rq) && 909 pm->pm_step == ide_pm_state_start_resume) { 910 /* 911 * The first thing we do on wakeup is to wait for BSY bit to 912 * go away (with a looong timeout) as a drive on this hwif may 913 * just be POSTing itself. 914 * We do that before even selecting as the "other" device on 915 * the bus may be broken enough to walk on our toes at this 916 * point. 917 */ 918 int rc; 919#ifdef DEBUG_PM 920 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); 921#endif 922 rc = ide_wait_not_busy(HWIF(drive), 35000); 923 if (rc) 924 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); 925 SELECT_DRIVE(drive); 926 if (IDE_CONTROL_REG) 927 HWIF(drive)->OUTB(drive->ctl, IDE_CONTROL_REG); 928 rc = ide_wait_not_busy(HWIF(drive), 100000); 929 if (rc) 930 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); 931 } 932} 933 934/** 935 * start_request - start of I/O and command issuing for IDE 936 * 937 * start_request() initiates handling of a new I/O request. It 938 * accepts commands and I/O (read/write) requests. It also does 939 * the final remapping for weird stuff like EZDrive. Once 940 * device mapper can work sector level the EZDrive stuff can go away 941 * 942 * FIXME: this function needs a rename 943 */ 944 945static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) 946{ 947 ide_startstop_t startstop; 948 sector_t block; 949 950 BUG_ON(!blk_rq_started(rq)); 951 952#ifdef DEBUG 953 printk("%s: start_request: current=0x%08lx\n", 954 HWIF(drive)->name, (unsigned long) rq); 955#endif 956 957 /* bail early if we've exceeded max_failures */ 958 if (drive->max_failures && (drive->failures > drive->max_failures)) { 959 rq->cmd_flags |= REQ_FAILED; 960 goto kill_rq; 961 } 962 963 block = rq->sector; 964 if (blk_fs_request(rq) && 965 (drive->media == ide_disk || drive->media == ide_floppy)) { 966 block += drive->sect0; 967 } 968 /* Yecch - this will shift the entire interval, 969 possibly killing some innocent following sector */ 970 if (block == 0 && drive->remap_0_to_1 == 1) 971 block = 1; /* redirect MBR access to EZ-Drive partn table */ 972 973 if (blk_pm_request(rq)) 974 ide_check_pm_state(drive, rq); 975 976 SELECT_DRIVE(drive); 977 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { 978 printk(KERN_ERR "%s: drive not ready for command\n", drive->name); 979 return startstop; 980 } 981 if (!drive->special.all) { 982 ide_driver_t *drv; 983 984 /* 985 * We reset the drive so we need to issue a SETFEATURES. 986 * Do it _after_ do_special() restored device parameters. 987 */ 988 if (drive->current_speed == 0xff) 989 ide_config_drive_speed(drive, drive->desired_speed); 990 991 if (rq->cmd_type == REQ_TYPE_ATA_CMD || 992 rq->cmd_type == REQ_TYPE_ATA_TASKFILE) 993 return execute_drive_cmd(drive, rq); 994 else if (blk_pm_request(rq)) { 995 struct request_pm_state *pm = rq->data; 996#ifdef DEBUG_PM 997 printk("%s: start_power_step(step: %d)\n", 998 drive->name, rq->pm->pm_step); 999#endif 1000 startstop = ide_start_power_step(drive, rq); 1001 if (startstop == ide_stopped && 1002 pm->pm_step == ide_pm_state_completed) 1003 ide_complete_pm_request(drive, rq); 1004 return startstop; 1005 } 1006 1007 drv = *(ide_driver_t **)rq->rq_disk->private_data; 1008 return drv->do_request(drive, rq, block); 1009 } 1010 return do_special(drive); 1011kill_rq: 1012 ide_kill_rq(drive, rq); 1013 return ide_stopped; 1014} 1015 1016/** 1017 * ide_stall_queue - pause an IDE device 1018 * @drive: drive to stall 1019 * @timeout: time to stall for (jiffies) 1020 * 1021 * ide_stall_queue() can be used by a drive to give excess bandwidth back 1022 * to the hwgroup by sleeping for timeout jiffies. 1023 */ 1024 1025void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) 1026{ 1027 if (timeout > WAIT_WORSTCASE) 1028 timeout = WAIT_WORSTCASE; 1029 drive->sleep = timeout + jiffies; 1030 drive->sleeping = 1; 1031} 1032 1033EXPORT_SYMBOL(ide_stall_queue); 1034 1035#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) 1036 1037/** 1038 * choose_drive - select a drive to service 1039 * @hwgroup: hardware group to select on 1040 * 1041 * choose_drive() selects the next drive which will be serviced. 1042 * This is necessary because the IDE layer can't issue commands 1043 * to both drives on the same cable, unlike SCSI. 1044 */ 1045 1046static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) 1047{ 1048 ide_drive_t *drive, *best; 1049 1050repeat: 1051 best = NULL; 1052 drive = hwgroup->drive; 1053 1054 /* 1055 * drive is doing pre-flush, ordered write, post-flush sequence. even 1056 * though that is 3 requests, it must be seen as a single transaction. 1057 * we must not preempt this drive until that is complete 1058 */ 1059 if (blk_queue_flushing(drive->queue)) { 1060 /* 1061 * small race where queue could get replugged during 1062 * the 3-request flush cycle, just yank the plug since 1063 * we want it to finish asap 1064 */ 1065 blk_remove_plug(drive->queue); 1066 return drive; 1067 } 1068 1069 do { 1070 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) 1071 && !elv_queue_empty(drive->queue)) { 1072 if (!best 1073 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) 1074 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) 1075 { 1076 if (!blk_queue_plugged(drive->queue)) 1077 best = drive; 1078 } 1079 } 1080 } while ((drive = drive->next) != hwgroup->drive); 1081 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { 1082 long t = (signed long)(WAKEUP(best) - jiffies); 1083 if (t >= WAIT_MIN_SLEEP) { 1084 /* 1085 * We *may* have some time to spare, but first let's see if 1086 * someone can potentially benefit from our nice mood today.. 1087 */ 1088 drive = best->next; 1089 do { 1090 if (!drive->sleeping 1091 && time_before(jiffies - best->service_time, WAKEUP(drive)) 1092 && time_before(WAKEUP(drive), jiffies + t)) 1093 { 1094 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); 1095 goto repeat; 1096 } 1097 } while ((drive = drive->next) != best); 1098 } 1099 } 1100 return best; 1101} 1102 1103/* 1104 * Issue a new request to a drive from hwgroup 1105 * Caller must have already done spin_lock_irqsave(&ide_lock, ..); 1106 * 1107 * A hwgroup is a serialized group of IDE interfaces. Usually there is 1108 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) 1109 * may have both interfaces in a single hwgroup to "serialize" access. 1110 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped 1111 * together into one hwgroup for serialized access. 1112 * 1113 * Note also that several hwgroups can end up sharing a single IRQ, 1114 * possibly along with many other devices. This is especially common in 1115 * PCI-based systems with off-board IDE controller cards. 1116 * 1117 * The IDE driver uses the single global ide_lock spinlock to protect 1118 * access to the request queues, and to protect the hwgroup->busy flag. 1119 * 1120 * The first thread into the driver for a particular hwgroup sets the 1121 * hwgroup->busy flag to indicate that this hwgroup is now active, 1122 * and then initiates processing of the top request from the request queue. 1123 * 1124 * Other threads attempting entry notice the busy setting, and will simply 1125 * queue their new requests and exit immediately. Note that hwgroup->busy 1126 * remains set even when the driver is merely awaiting the next interrupt. 1127 * Thus, the meaning is "this hwgroup is busy processing a request". 1128 * 1129 * When processing of a request completes, the completing thread or IRQ-handler 1130 * will start the next request from the queue. If no more work remains, 1131 * the driver will clear the hwgroup->busy flag and exit. 1132 * 1133 * The ide_lock (spinlock) is used to protect all access to the 1134 * hwgroup->busy flag, but is otherwise not needed for most processing in 1135 * the driver. This makes the driver much more friendlier to shared IRQs 1136 * than previous designs, while remaining 100% (?) SMP safe and capable. 1137 */ 1138static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) 1139{ 1140 ide_drive_t *drive; 1141 ide_hwif_t *hwif; 1142 struct request *rq; 1143 ide_startstop_t startstop; 1144 int loops = 0; 1145 1146 /* for atari only: POSSIBLY BROKEN HERE(?) */ 1147 ide_get_lock(ide_intr, hwgroup); 1148 1149 /* caller must own ide_lock */ 1150 BUG_ON(!irqs_disabled()); 1151 1152 while (!hwgroup->busy) { 1153 hwgroup->busy = 1; 1154 drive = choose_drive(hwgroup); 1155 if (drive == NULL) { 1156 int sleeping = 0; 1157 unsigned long sleep = 0; /* shut up, gcc */ 1158 hwgroup->rq = NULL; 1159 drive = hwgroup->drive; 1160 do { 1161 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { 1162 sleeping = 1; 1163 sleep = drive->sleep; 1164 } 1165 } while ((drive = drive->next) != hwgroup->drive); 1166 if (sleeping) { 1167 /* 1168 * Take a short snooze, and then wake up this hwgroup again. 1169 * This gives other hwgroups on the same a chance to 1170 * play fairly with us, just in case there are big differences 1171 * in relative throughputs.. don't want to hog the cpu too much. 1172 */ 1173 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) 1174 sleep = jiffies + WAIT_MIN_SLEEP; 1175#if 1 1176 if (timer_pending(&hwgroup->timer)) 1177 printk(KERN_CRIT "ide_set_handler: timer already active\n"); 1178#endif 1179 /* so that ide_timer_expiry knows what to do */ 1180 hwgroup->sleeping = 1; 1181 hwgroup->req_gen_timer = hwgroup->req_gen; 1182 mod_timer(&hwgroup->timer, sleep); 1183 /* we purposely leave hwgroup->busy==1 1184 * while sleeping */ 1185 } else { 1186 /* Ugly, but how can we sleep for the lock 1187 * otherwise? perhaps from tq_disk? 1188 */ 1189 1190 /* for atari only */ 1191 ide_release_lock(); 1192 hwgroup->busy = 0; 1193 } 1194 1195 /* no more work for this hwgroup (for now) */ 1196 return; 1197 } 1198 again: 1199 hwif = HWIF(drive); 1200 if (hwgroup->hwif->sharing_irq && 1201 hwif != hwgroup->hwif && 1202 hwif->io_ports[IDE_CONTROL_OFFSET]) { 1203 /* 1204 * set nIEN for previous hwif, drives in the 1205 * quirk_list may not like intr setups/cleanups 1206 */ 1207 if (drive->quirk_list != 1) 1208 hwif->OUTB(drive->ctl | 2, IDE_CONTROL_REG); 1209 } 1210 hwgroup->hwif = hwif; 1211 hwgroup->drive = drive; 1212 drive->sleeping = 0; 1213 drive->service_start = jiffies; 1214 1215 if (blk_queue_plugged(drive->queue)) { 1216 printk(KERN_ERR "ide: huh? queue was plugged!\n"); 1217 break; 1218 } 1219 1220 /* 1221 * we know that the queue isn't empty, but this can happen 1222 * if the q->prep_rq_fn() decides to kill a request 1223 */ 1224 rq = elv_next_request(drive->queue); 1225 if (!rq) { 1226 hwgroup->busy = 0; 1227 break; 1228 } 1229 1230 /* 1231 * Sanity: don't accept a request that isn't a PM request 1232 * if we are currently power managed. This is very important as 1233 * blk_stop_queue() doesn't prevent the elv_next_request() 1234 * above to return us whatever is in the queue. Since we call 1235 * ide_do_request() ourselves, we end up taking requests while 1236 * the queue is blocked... 1237 * 1238 * We let requests forced at head of queue with ide-preempt 1239 * though. I hope that doesn't happen too much, hopefully not 1240 * unless the subdriver triggers such a thing in its own PM 1241 * state machine. 1242 * 1243 * We count how many times we loop here to make sure we service 1244 * all drives in the hwgroup without looping for ever 1245 */ 1246 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) { 1247 drive = drive->next ? drive->next : hwgroup->drive; 1248 if (loops++ < 4 && !blk_queue_plugged(drive->queue)) 1249 goto again; 1250 /* We clear busy, there should be no pending ATA command at this point. */ 1251 hwgroup->busy = 0; 1252 break; 1253 } 1254 1255 hwgroup->rq = rq; 1256 1257 /* 1258 * Some systems have trouble with IDE IRQs arriving while 1259 * the driver is still setting things up. So, here we disable 1260 * the IRQ used by this interface while the request is being started. 1261 * This may look bad at first, but pretty much the same thing 1262 * happens anyway when any interrupt comes in, IDE or otherwise 1263 * -- the kernel masks the IRQ while it is being handled. 1264 */ 1265 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1266 disable_irq_nosync(hwif->irq); 1267 spin_unlock(&ide_lock); 1268 local_irq_enable_in_hardirq(); 1269 /* allow other IRQs while we start this request */ 1270 startstop = start_request(drive, rq); 1271 spin_lock_irq(&ide_lock); 1272 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1273 enable_irq(hwif->irq); 1274 if (startstop == ide_stopped) 1275 hwgroup->busy = 0; 1276 } 1277} 1278 1279/* 1280 * Passes the stuff to ide_do_request 1281 */ 1282void do_ide_request(struct request_queue *q) 1283{ 1284 ide_drive_t *drive = q->queuedata; 1285 1286 ide_do_request(HWGROUP(drive), IDE_NO_IRQ); 1287} 1288 1289/* 1290 * un-busy the hwgroup etc, and clear any pending DMA status. we want to 1291 * retry the current request in pio mode instead of risking tossing it 1292 * all away 1293 */ 1294static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) 1295{ 1296 ide_hwif_t *hwif = HWIF(drive); 1297 struct request *rq; 1298 ide_startstop_t ret = ide_stopped; 1299 1300 /* 1301 * end current dma transaction 1302 */ 1303 1304 if (error < 0) { 1305 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); 1306 (void)HWIF(drive)->ide_dma_end(drive); 1307 ret = ide_error(drive, "dma timeout error", 1308 hwif->INB(IDE_STATUS_REG)); 1309 } else { 1310 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); 1311 hwif->dma_timeout(drive); 1312 } 1313 1314 /* 1315 * disable dma for now, but remember that we did so because of 1316 * a timeout -- we'll reenable after we finish this next request 1317 * (or rather the first chunk of it) in pio. 1318 */ 1319 drive->retry_pio++; 1320 drive->state = DMA_PIO_RETRY; 1321 hwif->dma_off_quietly(drive); 1322 1323 /* 1324 * un-busy drive etc (hwgroup->busy is cleared on return) and 1325 * make sure request is sane 1326 */ 1327 rq = HWGROUP(drive)->rq; 1328 1329 if (!rq) 1330 goto out; 1331 1332 HWGROUP(drive)->rq = NULL; 1333 1334 rq->errors = 0; 1335 1336 if (!rq->bio) 1337 goto out; 1338 1339 rq->sector = rq->bio->bi_sector; 1340 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; 1341 rq->hard_cur_sectors = rq->current_nr_sectors; 1342 rq->buffer = bio_data(rq->bio); 1343out: 1344 return ret; 1345} 1346 1347/** 1348 * ide_timer_expiry - handle lack of an IDE interrupt 1349 * @data: timer callback magic (hwgroup) 1350 * 1351 * An IDE command has timed out before the expected drive return 1352 * occurred. At this point we attempt to clean up the current 1353 * mess. If the current handler includes an expiry handler then 1354 * we invoke the expiry handler, and providing it is happy the 1355 * work is done. If that fails we apply generic recovery rules 1356 * invoking the handler and checking the drive DMA status. We 1357 * have an excessively incestuous relationship with the DMA 1358 * logic that wants cleaning up. 1359 */ 1360 1361void ide_timer_expiry (unsigned long data) 1362{ 1363 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; 1364 ide_handler_t *handler; 1365 ide_expiry_t *expiry; 1366 unsigned long flags; 1367 unsigned long wait = -1; 1368 1369 spin_lock_irqsave(&ide_lock, flags); 1370 1371 if (((handler = hwgroup->handler) == NULL) || 1372 (hwgroup->req_gen != hwgroup->req_gen_timer)) { 1373 /* 1374 * Either a marginal timeout occurred 1375 * (got the interrupt just as timer expired), 1376 * or we were "sleeping" to give other devices a chance. 1377 * Either way, we don't really want to complain about anything. 1378 */ 1379 if (hwgroup->sleeping) { 1380 hwgroup->sleeping = 0; 1381 hwgroup->busy = 0; 1382 } 1383 } else { 1384 ide_drive_t *drive = hwgroup->drive; 1385 if (!drive) { 1386 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); 1387 hwgroup->handler = NULL; 1388 } else { 1389 ide_hwif_t *hwif; 1390 ide_startstop_t startstop = ide_stopped; 1391 if (!hwgroup->busy) { 1392 hwgroup->busy = 1; /* paranoia */ 1393 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); 1394 } 1395 if ((expiry = hwgroup->expiry) != NULL) { 1396 /* continue */ 1397 if ((wait = expiry(drive)) > 0) { 1398 /* reset timer */ 1399 hwgroup->timer.expires = jiffies + wait; 1400 hwgroup->req_gen_timer = hwgroup->req_gen; 1401 add_timer(&hwgroup->timer); 1402 spin_unlock_irqrestore(&ide_lock, flags); 1403 return; 1404 } 1405 } 1406 hwgroup->handler = NULL; 1407 /* 1408 * We need to simulate a real interrupt when invoking 1409 * the handler() function, which means we need to 1410 * globally mask the specific IRQ: 1411 */ 1412 spin_unlock(&ide_lock); 1413 hwif = HWIF(drive); 1414 /* disable_irq_nosync ?? */ 1415 disable_irq(hwif->irq); 1416 /* local CPU only, 1417 * as if we were handling an interrupt */ 1418 local_irq_disable(); 1419 if (hwgroup->polling) { 1420 startstop = handler(drive); 1421 } else if (drive_is_ready(drive)) { 1422 if (drive->waiting_for_dma) 1423 hwgroup->hwif->dma_lost_irq(drive); 1424 (void)ide_ack_intr(hwif); 1425 printk(KERN_WARNING "%s: lost interrupt\n", drive->name); 1426 startstop = handler(drive); 1427 } else { 1428 if (drive->waiting_for_dma) { 1429 startstop = ide_dma_timeout_retry(drive, wait); 1430 } else 1431 startstop = 1432 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG)); 1433 } 1434 drive->service_time = jiffies - drive->service_start; 1435 spin_lock_irq(&ide_lock); 1436 enable_irq(hwif->irq); 1437 if (startstop == ide_stopped) 1438 hwgroup->busy = 0; 1439 } 1440 } 1441 ide_do_request(hwgroup, IDE_NO_IRQ); 1442 spin_unlock_irqrestore(&ide_lock, flags); 1443} 1444 1445/** 1446 * unexpected_intr - handle an unexpected IDE interrupt 1447 * @irq: interrupt line 1448 * @hwgroup: hwgroup being processed 1449 * 1450 * There's nothing really useful we can do with an unexpected interrupt, 1451 * other than reading the status register (to clear it), and logging it. 1452 * There should be no way that an irq can happen before we're ready for it, 1453 * so we needn't worry much about losing an "important" interrupt here. 1454 * 1455 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever 1456 * the drive enters "idle", "standby", or "sleep" mode, so if the status 1457 * looks "good", we just ignore the interrupt completely. 1458 * 1459 * This routine assumes __cli() is in effect when called. 1460 * 1461 * If an unexpected interrupt happens on irq15 while we are handling irq14 1462 * and if the two interfaces are "serialized" (CMD640), then it looks like 1463 * we could screw up by interfering with a new request being set up for 1464 * irq15. 1465 * 1466 * In reality, this is a non-issue. The new command is not sent unless 1467 * the drive is ready to accept one, in which case we know the drive is 1468 * not trying to interrupt us. And ide_set_handler() is always invoked 1469 * before completing the issuance of any new drive command, so we will not 1470 * be accidentally invoked as a result of any valid command completion 1471 * interrupt. 1472 * 1473 * Note that we must walk the entire hwgroup here. We know which hwif 1474 * is doing the current command, but we don't know which hwif burped 1475 * mysteriously. 1476 */ 1477 1478static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) 1479{ 1480 u8 stat; 1481 ide_hwif_t *hwif = hwgroup->hwif; 1482 1483 /* 1484 * handle the unexpected interrupt 1485 */ 1486 do { 1487 if (hwif->irq == irq) { 1488 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1489 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { 1490 /* Try to not flood the console with msgs */ 1491 static unsigned long last_msgtime, count; 1492 ++count; 1493 if (time_after(jiffies, last_msgtime + HZ)) { 1494 last_msgtime = jiffies; 1495 printk(KERN_ERR "%s%s: unexpected interrupt, " 1496 "status=0x%02x, count=%ld\n", 1497 hwif->name, 1498 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); 1499 } 1500 } 1501 } 1502 } while ((hwif = hwif->next) != hwgroup->hwif); 1503} 1504 1505/** 1506 * ide_intr - default IDE interrupt handler 1507 * @irq: interrupt number 1508 * @dev_id: hwif group 1509 * @regs: unused weirdness from the kernel irq layer 1510 * 1511 * This is the default IRQ handler for the IDE layer. You should 1512 * not need to override it. If you do be aware it is subtle in 1513 * places 1514 * 1515 * hwgroup->hwif is the interface in the group currently performing 1516 * a command. hwgroup->drive is the drive and hwgroup->handler is 1517 * the IRQ handler to call. As we issue a command the handlers 1518 * step through multiple states, reassigning the handler to the 1519 * next step in the process. Unlike a smart SCSI controller IDE 1520 * expects the main processor to sequence the various transfer 1521 * stages. We also manage a poll timer to catch up with most 1522 * timeout situations. There are still a few where the handlers 1523 * don't ever decide to give up. 1524 * 1525 * The handler eventually returns ide_stopped to indicate the 1526 * request completed. At this point we issue the next request 1527 * on the hwgroup and the process begins again. 1528 */ 1529 1530irqreturn_t ide_intr (int irq, void *dev_id) 1531{ 1532 unsigned long flags; 1533 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; 1534 ide_hwif_t *hwif; 1535 ide_drive_t *drive; 1536 ide_handler_t *handler; 1537 ide_startstop_t startstop; 1538 1539 spin_lock_irqsave(&ide_lock, flags); 1540 hwif = hwgroup->hwif; 1541 1542 if (!ide_ack_intr(hwif)) { 1543 spin_unlock_irqrestore(&ide_lock, flags); 1544 return IRQ_NONE; 1545 } 1546 1547 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { 1548 /* 1549 * Not expecting an interrupt from this drive. 1550 * That means this could be: 1551 * (1) an interrupt from another PCI device 1552 * sharing the same PCI INT# as us. 1553 * or (2) a drive just entered sleep or standby mode, 1554 * and is interrupting to let us know. 1555 * or (3) a spurious interrupt of unknown origin. 1556 * 1557 * For PCI, we cannot tell the difference, 1558 * so in that case we just ignore it and hope it goes away. 1559 * 1560 * FIXME: unexpected_intr should be hwif-> then we can 1561 * remove all the ifdef PCI crap 1562 */ 1563#ifdef CONFIG_BLK_DEV_IDEPCI 1564 if (hwif->pci_dev && !hwif->pci_dev->vendor) 1565#endif /* CONFIG_BLK_DEV_IDEPCI */ 1566 { 1567 /* 1568 * Probably not a shared PCI interrupt, 1569 * so we can safely try to do something about it: 1570 */ 1571 unexpected_intr(irq, hwgroup); 1572#ifdef CONFIG_BLK_DEV_IDEPCI 1573 } else { 1574 /* 1575 * Whack the status register, just in case 1576 * we have a leftover pending IRQ. 1577 */ 1578 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1579#endif /* CONFIG_BLK_DEV_IDEPCI */ 1580 } 1581 spin_unlock_irqrestore(&ide_lock, flags); 1582 return IRQ_NONE; 1583 } 1584 drive = hwgroup->drive; 1585 if (!drive) { 1586 /* 1587 * This should NEVER happen, and there isn't much 1588 * we could do about it here. 1589 * 1590 * [Note - this can occur if the drive is hot unplugged] 1591 */ 1592 spin_unlock_irqrestore(&ide_lock, flags); 1593 return IRQ_HANDLED; 1594 } 1595 if (!drive_is_ready(drive)) { 1596 /* 1597 * This happens regularly when we share a PCI IRQ with 1598 * another device. Unfortunately, it can also happen 1599 * with some buggy drives that trigger the IRQ before 1600 * their status register is up to date. Hopefully we have 1601 * enough advance overhead that the latter isn't a problem. 1602 */ 1603 spin_unlock_irqrestore(&ide_lock, flags); 1604 return IRQ_NONE; 1605 } 1606 if (!hwgroup->busy) { 1607 hwgroup->busy = 1; /* paranoia */ 1608 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); 1609 } 1610 hwgroup->handler = NULL; 1611 hwgroup->req_gen++; 1612 del_timer(&hwgroup->timer); 1613 spin_unlock(&ide_lock); 1614 1615 /* Some controllers might set DMA INTR no matter DMA or PIO; 1616 * bmdma status might need to be cleared even for 1617 * PIO interrupts to prevent spurious/lost irq. 1618 */ 1619 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma)) 1620 /* ide_dma_end() needs bmdma status for error checking. 1621 * So, skip clearing bmdma status here and leave it 1622 * to ide_dma_end() if this is dma interrupt. 1623 */ 1624 hwif->ide_dma_clear_irq(drive); 1625 1626 if (drive->unmask) 1627 local_irq_enable_in_hardirq(); 1628 /* service this interrupt, may set handler for next interrupt */ 1629 startstop = handler(drive); 1630 spin_lock_irq(&ide_lock); 1631 1632 /* 1633 * Note that handler() may have set things up for another 1634 * interrupt to occur soon, but it cannot happen until 1635 * we exit from this routine, because it will be the 1636 * same irq as is currently being serviced here, and Linux 1637 * won't allow another of the same (on any CPU) until we return. 1638 */ 1639 drive->service_time = jiffies - drive->service_start; 1640 if (startstop == ide_stopped) { 1641 if (hwgroup->handler == NULL) { /* paranoia */ 1642 hwgroup->busy = 0; 1643 ide_do_request(hwgroup, hwif->irq); 1644 } else { 1645 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " 1646 "on exit\n", drive->name); 1647 } 1648 } 1649 spin_unlock_irqrestore(&ide_lock, flags); 1650 return IRQ_HANDLED; 1651} 1652 1653/** 1654 * ide_init_drive_cmd - initialize a drive command request 1655 * @rq: request object 1656 * 1657 * Initialize a request before we fill it in and send it down to 1658 * ide_do_drive_cmd. Commands must be set up by this function. Right 1659 * now it doesn't do a lot, but if that changes abusers will have a 1660 * nasty surprise. 1661 */ 1662 1663void ide_init_drive_cmd (struct request *rq) 1664{ 1665 memset(rq, 0, sizeof(*rq)); 1666 rq->cmd_type = REQ_TYPE_ATA_CMD; 1667 rq->ref_count = 1; 1668} 1669 1670EXPORT_SYMBOL(ide_init_drive_cmd); 1671 1672/** 1673 * ide_do_drive_cmd - issue IDE special command 1674 * @drive: device to issue command 1675 * @rq: request to issue 1676 * @action: action for processing 1677 * 1678 * This function issues a special IDE device request 1679 * onto the request queue. 1680 * 1681 * If action is ide_wait, then the rq is queued at the end of the 1682 * request queue, and the function sleeps until it has been processed. 1683 * This is for use when invoked from an ioctl handler. 1684 * 1685 * If action is ide_preempt, then the rq is queued at the head of 1686 * the request queue, displacing the currently-being-processed 1687 * request and this function returns immediately without waiting 1688 * for the new rq to be completed. This is VERY DANGEROUS, and is 1689 * intended for careful use by the ATAPI tape/cdrom driver code. 1690 * 1691 * If action is ide_end, then the rq is queued at the end of the 1692 * request queue, and the function returns immediately without waiting 1693 * for the new rq to be completed. This is again intended for careful 1694 * use by the ATAPI tape/cdrom driver code. 1695 */ 1696 1697int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) 1698{ 1699 unsigned long flags; 1700 ide_hwgroup_t *hwgroup = HWGROUP(drive); 1701 DECLARE_COMPLETION_ONSTACK(wait); 1702 int where = ELEVATOR_INSERT_BACK, err; 1703 int must_wait = (action == ide_wait || action == ide_head_wait); 1704 1705 rq->errors = 0; 1706 1707 /* 1708 * we need to hold an extra reference to request for safe inspection 1709 * after completion 1710 */ 1711 if (must_wait) { 1712 rq->ref_count++; 1713 rq->end_io_data = &wait; 1714 rq->end_io = blk_end_sync_rq; 1715 } 1716 1717 spin_lock_irqsave(&ide_lock, flags); 1718 if (action == ide_preempt) 1719 hwgroup->rq = NULL; 1720 if (action == ide_preempt || action == ide_head_wait) { 1721 where = ELEVATOR_INSERT_FRONT; 1722 rq->cmd_flags |= REQ_PREEMPT; 1723 } 1724 __elv_add_request(drive->queue, rq, where, 0); 1725 ide_do_request(hwgroup, IDE_NO_IRQ); 1726 spin_unlock_irqrestore(&ide_lock, flags); 1727 1728 err = 0; 1729 if (must_wait) { 1730 wait_for_completion(&wait); 1731 if (rq->errors) 1732 err = -EIO; 1733 1734 blk_put_request(rq); 1735 } 1736 1737 return err; 1738} 1739 1740EXPORT_SYMBOL(ide_do_drive_cmd); 1741 1742void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma) 1743{ 1744 ide_task_t task; 1745 1746 memset(&task, 0, sizeof(task)); 1747 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM | 1748 IDE_TFLAG_OUT_FEATURE | tf_flags; 1749 task.tf.feature = dma; /* Use PIO/DMA */ 1750 task.tf.lbam = bcount & 0xff; 1751 task.tf.lbah = (bcount >> 8) & 0xff; 1752 1753 ide_tf_load(drive, &task); 1754} 1755 1756EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load); 1757