ide-io.c revision 1192e528e064ebb9a578219731d2b0f78ca3c1ec
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->data_phase = TASKFILE_NO_DATA; 237 return do_rw_taskfile(drive, args); 238} 239 240/** 241 * ide_end_dequeued_request - complete an IDE I/O 242 * @drive: IDE device for the I/O 243 * @uptodate: 244 * @nr_sectors: number of sectors completed 245 * 246 * Complete an I/O that is no longer on the request queue. This 247 * typically occurs when we pull the request and issue a REQUEST_SENSE. 248 * We must still finish the old request but we must not tamper with the 249 * queue in the meantime. 250 * 251 * NOTE: This path does not handle barrier, but barrier is not supported 252 * on ide-cd anyway. 253 */ 254 255int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq, 256 int uptodate, int nr_sectors) 257{ 258 unsigned long flags; 259 int ret; 260 261 spin_lock_irqsave(&ide_lock, flags); 262 BUG_ON(!blk_rq_started(rq)); 263 ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0); 264 spin_unlock_irqrestore(&ide_lock, flags); 265 266 return ret; 267} 268EXPORT_SYMBOL_GPL(ide_end_dequeued_request); 269 270 271/** 272 * ide_complete_pm_request - end the current Power Management request 273 * @drive: target drive 274 * @rq: request 275 * 276 * This function cleans up the current PM request and stops the queue 277 * if necessary. 278 */ 279static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq) 280{ 281 unsigned long flags; 282 283#ifdef DEBUG_PM 284 printk("%s: completing PM request, %s\n", drive->name, 285 blk_pm_suspend_request(rq) ? "suspend" : "resume"); 286#endif 287 spin_lock_irqsave(&ide_lock, flags); 288 if (blk_pm_suspend_request(rq)) { 289 blk_stop_queue(drive->queue); 290 } else { 291 drive->blocked = 0; 292 blk_start_queue(drive->queue); 293 } 294 blkdev_dequeue_request(rq); 295 HWGROUP(drive)->rq = NULL; 296 end_that_request_last(rq, 1); 297 spin_unlock_irqrestore(&ide_lock, flags); 298} 299 300/** 301 * ide_end_drive_cmd - end an explicit drive command 302 * @drive: command 303 * @stat: status bits 304 * @err: error bits 305 * 306 * Clean up after success/failure of an explicit drive command. 307 * These get thrown onto the queue so they are synchronized with 308 * real I/O operations on the drive. 309 * 310 * In LBA48 mode we have to read the register set twice to get 311 * all the extra information out. 312 */ 313 314void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) 315{ 316 ide_hwif_t *hwif = HWIF(drive); 317 unsigned long flags; 318 struct request *rq; 319 320 spin_lock_irqsave(&ide_lock, flags); 321 rq = HWGROUP(drive)->rq; 322 spin_unlock_irqrestore(&ide_lock, flags); 323 324 if (rq->cmd_type == REQ_TYPE_ATA_CMD) { 325 u8 *args = (u8 *) rq->buffer; 326 if (rq->errors == 0) 327 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 328 329 if (args) { 330 args[0] = stat; 331 args[1] = err; 332 args[2] = hwif->INB(IDE_NSECTOR_REG); 333 } 334 } else if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 335 ide_task_t *args = (ide_task_t *) rq->special; 336 if (rq->errors == 0) 337 rq->errors = !OK_STAT(stat,READY_STAT,BAD_STAT); 338 339 if (args) { 340 struct ide_taskfile *tf = &args->tf; 341 342 if (args->tf_flags & IDE_TFLAG_IN_DATA) { 343 u16 data = hwif->INW(IDE_DATA_REG); 344 345 tf->data = data & 0xff; 346 tf->hob_data = (data >> 8) & 0xff; 347 } 348 tf->error = err; 349 /* be sure we're looking at the low order bits */ 350 hwif->OUTB(drive->ctl & ~0x80, IDE_CONTROL_REG); 351 tf->nsect = hwif->INB(IDE_NSECTOR_REG); 352 tf->lbal = hwif->INB(IDE_SECTOR_REG); 353 tf->lbam = hwif->INB(IDE_LCYL_REG); 354 tf->lbah = hwif->INB(IDE_HCYL_REG); 355 tf->device = hwif->INB(IDE_SELECT_REG); 356 tf->status = stat; 357 358 if (args->tf_flags & IDE_TFLAG_LBA48) { 359 hwif->OUTB(drive->ctl|0x80, IDE_CONTROL_REG); 360 tf->hob_feature = hwif->INB(IDE_FEATURE_REG); 361 tf->hob_nsect = hwif->INB(IDE_NSECTOR_REG); 362 tf->hob_lbal = hwif->INB(IDE_SECTOR_REG); 363 tf->hob_lbam = hwif->INB(IDE_LCYL_REG); 364 tf->hob_lbah = hwif->INB(IDE_HCYL_REG); 365 } 366 } 367 } else if (blk_pm_request(rq)) { 368 struct request_pm_state *pm = rq->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 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) 453 try_to_flush_leftover_data(drive); 454 455 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) { 456 ide_kill_rq(drive, rq); 457 return ide_stopped; 458 } 459 460 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 461 rq->errors |= ERROR_RESET; 462 463 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 464 ++rq->errors; 465 return ide_do_reset(drive); 466 } 467 468 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) 469 drive->special.b.recalibrate = 1; 470 471 ++rq->errors; 472 473 return ide_stopped; 474} 475 476static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 477{ 478 ide_hwif_t *hwif = drive->hwif; 479 480 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 481 /* other bits are useless when BUSY */ 482 rq->errors |= ERROR_RESET; 483 } else { 484 /* add decoding error stuff */ 485 } 486 487 if (hwif->INB(IDE_STATUS_REG) & (BUSY_STAT|DRQ_STAT)) 488 /* force an abort */ 489 hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG); 490 491 if (rq->errors >= ERROR_MAX) { 492 ide_kill_rq(drive, rq); 493 } else { 494 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 495 ++rq->errors; 496 return ide_do_reset(drive); 497 } 498 ++rq->errors; 499 } 500 501 return ide_stopped; 502} 503 504ide_startstop_t 505__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 506{ 507 if (drive->media == ide_disk) 508 return ide_ata_error(drive, rq, stat, err); 509 return ide_atapi_error(drive, rq, stat, err); 510} 511 512EXPORT_SYMBOL_GPL(__ide_error); 513 514/** 515 * ide_error - handle an error on the IDE 516 * @drive: drive the error occurred on 517 * @msg: message to report 518 * @stat: status bits 519 * 520 * ide_error() takes action based on the error returned by the drive. 521 * For normal I/O that may well include retries. We deal with 522 * both new-style (taskfile) and old style command handling here. 523 * In the case of taskfile command handling there is work left to 524 * do 525 */ 526 527ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) 528{ 529 struct request *rq; 530 u8 err; 531 532 err = ide_dump_status(drive, msg, stat); 533 534 if ((rq = HWGROUP(drive)->rq) == NULL) 535 return ide_stopped; 536 537 /* retry only "normal" I/O: */ 538 if (!blk_fs_request(rq)) { 539 rq->errors = 1; 540 ide_end_drive_cmd(drive, stat, err); 541 return ide_stopped; 542 } 543 544 if (rq->rq_disk) { 545 ide_driver_t *drv; 546 547 drv = *(ide_driver_t **)rq->rq_disk->private_data; 548 return drv->error(drive, rq, stat, err); 549 } else 550 return __ide_error(drive, rq, stat, err); 551} 552 553EXPORT_SYMBOL_GPL(ide_error); 554 555ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) 556{ 557 if (drive->media != ide_disk) 558 rq->errors |= ERROR_RESET; 559 560 ide_kill_rq(drive, rq); 561 562 return ide_stopped; 563} 564 565EXPORT_SYMBOL_GPL(__ide_abort); 566 567/** 568 * ide_abort - abort pending IDE operations 569 * @drive: drive the error occurred on 570 * @msg: message to report 571 * 572 * ide_abort kills and cleans up when we are about to do a 573 * host initiated reset on active commands. Longer term we 574 * want handlers to have sensible abort handling themselves 575 * 576 * This differs fundamentally from ide_error because in 577 * this case the command is doing just fine when we 578 * blow it away. 579 */ 580 581ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) 582{ 583 struct request *rq; 584 585 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) 586 return ide_stopped; 587 588 /* retry only "normal" I/O: */ 589 if (!blk_fs_request(rq)) { 590 rq->errors = 1; 591 ide_end_drive_cmd(drive, BUSY_STAT, 0); 592 return ide_stopped; 593 } 594 595 if (rq->rq_disk) { 596 ide_driver_t *drv; 597 598 drv = *(ide_driver_t **)rq->rq_disk->private_data; 599 return drv->abort(drive, rq); 600 } else 601 return __ide_abort(drive, rq); 602} 603 604/** 605 * drive_cmd_intr - drive command completion interrupt 606 * @drive: drive the completion interrupt occurred on 607 * 608 * drive_cmd_intr() is invoked on completion of a special DRIVE_CMD. 609 * We do any necessary data reading and then wait for the drive to 610 * go non busy. At that point we may read the error data and complete 611 * the request 612 */ 613 614static ide_startstop_t drive_cmd_intr (ide_drive_t *drive) 615{ 616 struct request *rq = HWGROUP(drive)->rq; 617 ide_hwif_t *hwif = HWIF(drive); 618 u8 *args = (u8 *) rq->buffer; 619 u8 stat = hwif->INB(IDE_STATUS_REG); 620 int retries = 10; 621 622 local_irq_enable_in_hardirq(); 623 if (rq->cmd_type == REQ_TYPE_ATA_CMD && 624 (stat & DRQ_STAT) && args && args[3]) { 625 u8 io_32bit = drive->io_32bit; 626 drive->io_32bit = 0; 627 hwif->ata_input_data(drive, &args[4], args[3] * SECTOR_WORDS); 628 drive->io_32bit = io_32bit; 629 while (((stat = hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) && retries--) 630 udelay(100); 631 } 632 633 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) 634 return ide_error(drive, "drive_cmd", stat); 635 /* calls ide_end_drive_cmd */ 636 ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG)); 637 return ide_stopped; 638} 639 640static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task) 641{ 642 task->tf.nsect = drive->sect; 643 task->tf.lbal = drive->sect; 644 task->tf.lbam = drive->cyl; 645 task->tf.lbah = drive->cyl >> 8; 646 task->tf.device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA; 647 task->tf.command = WIN_SPECIFY; 648 649 task->handler = &set_geometry_intr; 650} 651 652static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task) 653{ 654 task->tf.nsect = drive->sect; 655 task->tf.command = WIN_RESTORE; 656 657 task->handler = &recal_intr; 658} 659 660static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task) 661{ 662 task->tf.nsect = drive->mult_req; 663 task->tf.command = WIN_SETMULT; 664 665 task->handler = &set_multmode_intr; 666} 667 668static ide_startstop_t ide_disk_special(ide_drive_t *drive) 669{ 670 special_t *s = &drive->special; 671 ide_task_t args; 672 673 memset(&args, 0, sizeof(ide_task_t)); 674 args.data_phase = TASKFILE_NO_DATA; 675 676 if (s->b.set_geometry) { 677 s->b.set_geometry = 0; 678 ide_init_specify_cmd(drive, &args); 679 } else if (s->b.recalibrate) { 680 s->b.recalibrate = 0; 681 ide_init_restore_cmd(drive, &args); 682 } else if (s->b.set_multmode) { 683 s->b.set_multmode = 0; 684 if (drive->mult_req > drive->id->max_multsect) 685 drive->mult_req = drive->id->max_multsect; 686 ide_init_setmult_cmd(drive, &args); 687 } else if (s->all) { 688 int special = s->all; 689 s->all = 0; 690 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); 691 return ide_stopped; 692 } 693 694 args.tf_flags = IDE_TFLAG_OUT_TF | IDE_TFLAG_OUT_DEVICE; 695 696 do_rw_taskfile(drive, &args); 697 698 return ide_started; 699} 700 701/* 702 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away 703 */ 704static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio) 705{ 706 switch (req_pio) { 707 case 202: 708 case 201: 709 case 200: 710 case 102: 711 case 101: 712 case 100: 713 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0; 714 case 9: 715 case 8: 716 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0; 717 case 7: 718 case 6: 719 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0; 720 default: 721 return 0; 722 } 723} 724 725/** 726 * do_special - issue some special commands 727 * @drive: drive the command is for 728 * 729 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT 730 * commands to a drive. It used to do much more, but has been scaled 731 * back. 732 */ 733 734static ide_startstop_t do_special (ide_drive_t *drive) 735{ 736 special_t *s = &drive->special; 737 738#ifdef DEBUG 739 printk("%s: do_special: 0x%02x\n", drive->name, s->all); 740#endif 741 if (s->b.set_tune) { 742 ide_hwif_t *hwif = drive->hwif; 743 u8 req_pio = drive->tune_req; 744 745 s->b.set_tune = 0; 746 747 if (set_pio_mode_abuse(drive->hwif, req_pio)) { 748 749 if (hwif->set_pio_mode == NULL) 750 return ide_stopped; 751 752 /* 753 * take ide_lock for drive->[no_]unmask/[no_]io_32bit 754 */ 755 if (req_pio == 8 || req_pio == 9) { 756 unsigned long flags; 757 758 spin_lock_irqsave(&ide_lock, flags); 759 hwif->set_pio_mode(drive, req_pio); 760 spin_unlock_irqrestore(&ide_lock, flags); 761 } else 762 hwif->set_pio_mode(drive, req_pio); 763 } else { 764 int keep_dma = drive->using_dma; 765 766 ide_set_pio(drive, req_pio); 767 768 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) { 769 if (keep_dma) 770 hwif->ide_dma_on(drive); 771 } 772 } 773 774 return ide_stopped; 775 } else { 776 if (drive->media == ide_disk) 777 return ide_disk_special(drive); 778 779 s->all = 0; 780 drive->mult_req = 0; 781 return ide_stopped; 782 } 783} 784 785void ide_map_sg(ide_drive_t *drive, struct request *rq) 786{ 787 ide_hwif_t *hwif = drive->hwif; 788 struct scatterlist *sg = hwif->sg_table; 789 790 if (hwif->sg_mapped) /* needed by ide-scsi */ 791 return; 792 793 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) { 794 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); 795 } else { 796 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); 797 hwif->sg_nents = 1; 798 } 799} 800 801EXPORT_SYMBOL_GPL(ide_map_sg); 802 803void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) 804{ 805 ide_hwif_t *hwif = drive->hwif; 806 807 hwif->nsect = hwif->nleft = rq->nr_sectors; 808 hwif->cursg_ofs = 0; 809 hwif->cursg = NULL; 810} 811 812EXPORT_SYMBOL_GPL(ide_init_sg_cmd); 813 814/** 815 * execute_drive_command - issue special drive command 816 * @drive: the drive to issue the command on 817 * @rq: the request structure holding the command 818 * 819 * execute_drive_cmd() issues a special drive command, usually 820 * initiated by ioctl() from the external hdparm program. The 821 * command can be a drive command, drive task or taskfile 822 * operation. Weirdly you can call it with NULL to wait for 823 * all commands to finish. Don't do this as that is due to change 824 */ 825 826static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, 827 struct request *rq) 828{ 829 ide_hwif_t *hwif = HWIF(drive); 830 u8 *args = rq->buffer; 831 ide_task_t ltask; 832 struct ide_taskfile *tf = <ask.tf; 833 834 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 835 ide_task_t *task = rq->special; 836 837 if (task == NULL) 838 goto done; 839 840 hwif->data_phase = task->data_phase; 841 842 switch (hwif->data_phase) { 843 case TASKFILE_MULTI_OUT: 844 case TASKFILE_OUT: 845 case TASKFILE_MULTI_IN: 846 case TASKFILE_IN: 847 ide_init_sg_cmd(drive, rq); 848 ide_map_sg(drive, rq); 849 default: 850 break; 851 } 852 853 return do_rw_taskfile(drive, task); 854 } 855 856 if (args == NULL) 857 goto done; 858 859 memset(<ask, 0, sizeof(ltask)); 860 if (rq->cmd_type == REQ_TYPE_ATA_CMD) { 861#ifdef DEBUG 862 printk("%s: DRIVE_CMD\n", drive->name); 863#endif 864 tf->feature = args[2]; 865 if (args[0] == WIN_SMART) { 866 tf->nsect = args[3]; 867 tf->lbal = args[1]; 868 tf->lbam = 0x4f; 869 tf->lbah = 0xc2; 870 ltask.tf_flags = IDE_TFLAG_OUT_TF; 871 } else { 872 tf->nsect = args[1]; 873 ltask.tf_flags = IDE_TFLAG_OUT_FEATURE | 874 IDE_TFLAG_OUT_NSECT; 875 } 876 } 877 tf->command = args[0]; 878 ide_tf_load(drive, <ask); 879 ide_execute_command(drive, args[0], &drive_cmd_intr, WAIT_WORSTCASE, NULL); 880 return ide_started; 881 882done: 883 /* 884 * NULL is actually a valid way of waiting for 885 * all current requests to be flushed from the queue. 886 */ 887#ifdef DEBUG 888 printk("%s: DRIVE_CMD (null)\n", drive->name); 889#endif 890 ide_end_drive_cmd(drive, 891 hwif->INB(IDE_STATUS_REG), 892 hwif->INB(IDE_ERROR_REG)); 893 return ide_stopped; 894} 895 896static void ide_check_pm_state(ide_drive_t *drive, struct request *rq) 897{ 898 struct request_pm_state *pm = rq->data; 899 900 if (blk_pm_suspend_request(rq) && 901 pm->pm_step == ide_pm_state_start_suspend) 902 /* Mark drive blocked when starting the suspend sequence. */ 903 drive->blocked = 1; 904 else if (blk_pm_resume_request(rq) && 905 pm->pm_step == ide_pm_state_start_resume) { 906 /* 907 * The first thing we do on wakeup is to wait for BSY bit to 908 * go away (with a looong timeout) as a drive on this hwif may 909 * just be POSTing itself. 910 * We do that before even selecting as the "other" device on 911 * the bus may be broken enough to walk on our toes at this 912 * point. 913 */ 914 int rc; 915#ifdef DEBUG_PM 916 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); 917#endif 918 rc = ide_wait_not_busy(HWIF(drive), 35000); 919 if (rc) 920 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); 921 SELECT_DRIVE(drive); 922 if (IDE_CONTROL_REG) 923 HWIF(drive)->OUTB(drive->ctl, IDE_CONTROL_REG); 924 rc = ide_wait_not_busy(HWIF(drive), 100000); 925 if (rc) 926 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); 927 } 928} 929 930/** 931 * start_request - start of I/O and command issuing for IDE 932 * 933 * start_request() initiates handling of a new I/O request. It 934 * accepts commands and I/O (read/write) requests. It also does 935 * the final remapping for weird stuff like EZDrive. Once 936 * device mapper can work sector level the EZDrive stuff can go away 937 * 938 * FIXME: this function needs a rename 939 */ 940 941static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) 942{ 943 ide_startstop_t startstop; 944 sector_t block; 945 946 BUG_ON(!blk_rq_started(rq)); 947 948#ifdef DEBUG 949 printk("%s: start_request: current=0x%08lx\n", 950 HWIF(drive)->name, (unsigned long) rq); 951#endif 952 953 /* bail early if we've exceeded max_failures */ 954 if (drive->max_failures && (drive->failures > drive->max_failures)) { 955 rq->cmd_flags |= REQ_FAILED; 956 goto kill_rq; 957 } 958 959 block = rq->sector; 960 if (blk_fs_request(rq) && 961 (drive->media == ide_disk || drive->media == ide_floppy)) { 962 block += drive->sect0; 963 } 964 /* Yecch - this will shift the entire interval, 965 possibly killing some innocent following sector */ 966 if (block == 0 && drive->remap_0_to_1 == 1) 967 block = 1; /* redirect MBR access to EZ-Drive partn table */ 968 969 if (blk_pm_request(rq)) 970 ide_check_pm_state(drive, rq); 971 972 SELECT_DRIVE(drive); 973 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { 974 printk(KERN_ERR "%s: drive not ready for command\n", drive->name); 975 return startstop; 976 } 977 if (!drive->special.all) { 978 ide_driver_t *drv; 979 980 /* 981 * We reset the drive so we need to issue a SETFEATURES. 982 * Do it _after_ do_special() restored device parameters. 983 */ 984 if (drive->current_speed == 0xff) 985 ide_config_drive_speed(drive, drive->desired_speed); 986 987 if (rq->cmd_type == REQ_TYPE_ATA_CMD || 988 rq->cmd_type == REQ_TYPE_ATA_TASKFILE) 989 return execute_drive_cmd(drive, rq); 990 else if (blk_pm_request(rq)) { 991 struct request_pm_state *pm = rq->data; 992#ifdef DEBUG_PM 993 printk("%s: start_power_step(step: %d)\n", 994 drive->name, rq->pm->pm_step); 995#endif 996 startstop = ide_start_power_step(drive, rq); 997 if (startstop == ide_stopped && 998 pm->pm_step == ide_pm_state_completed) 999 ide_complete_pm_request(drive, rq); 1000 return startstop; 1001 } 1002 1003 drv = *(ide_driver_t **)rq->rq_disk->private_data; 1004 return drv->do_request(drive, rq, block); 1005 } 1006 return do_special(drive); 1007kill_rq: 1008 ide_kill_rq(drive, rq); 1009 return ide_stopped; 1010} 1011 1012/** 1013 * ide_stall_queue - pause an IDE device 1014 * @drive: drive to stall 1015 * @timeout: time to stall for (jiffies) 1016 * 1017 * ide_stall_queue() can be used by a drive to give excess bandwidth back 1018 * to the hwgroup by sleeping for timeout jiffies. 1019 */ 1020 1021void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) 1022{ 1023 if (timeout > WAIT_WORSTCASE) 1024 timeout = WAIT_WORSTCASE; 1025 drive->sleep = timeout + jiffies; 1026 drive->sleeping = 1; 1027} 1028 1029EXPORT_SYMBOL(ide_stall_queue); 1030 1031#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) 1032 1033/** 1034 * choose_drive - select a drive to service 1035 * @hwgroup: hardware group to select on 1036 * 1037 * choose_drive() selects the next drive which will be serviced. 1038 * This is necessary because the IDE layer can't issue commands 1039 * to both drives on the same cable, unlike SCSI. 1040 */ 1041 1042static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) 1043{ 1044 ide_drive_t *drive, *best; 1045 1046repeat: 1047 best = NULL; 1048 drive = hwgroup->drive; 1049 1050 /* 1051 * drive is doing pre-flush, ordered write, post-flush sequence. even 1052 * though that is 3 requests, it must be seen as a single transaction. 1053 * we must not preempt this drive until that is complete 1054 */ 1055 if (blk_queue_flushing(drive->queue)) { 1056 /* 1057 * small race where queue could get replugged during 1058 * the 3-request flush cycle, just yank the plug since 1059 * we want it to finish asap 1060 */ 1061 blk_remove_plug(drive->queue); 1062 return drive; 1063 } 1064 1065 do { 1066 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) 1067 && !elv_queue_empty(drive->queue)) { 1068 if (!best 1069 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) 1070 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) 1071 { 1072 if (!blk_queue_plugged(drive->queue)) 1073 best = drive; 1074 } 1075 } 1076 } while ((drive = drive->next) != hwgroup->drive); 1077 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { 1078 long t = (signed long)(WAKEUP(best) - jiffies); 1079 if (t >= WAIT_MIN_SLEEP) { 1080 /* 1081 * We *may* have some time to spare, but first let's see if 1082 * someone can potentially benefit from our nice mood today.. 1083 */ 1084 drive = best->next; 1085 do { 1086 if (!drive->sleeping 1087 && time_before(jiffies - best->service_time, WAKEUP(drive)) 1088 && time_before(WAKEUP(drive), jiffies + t)) 1089 { 1090 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); 1091 goto repeat; 1092 } 1093 } while ((drive = drive->next) != best); 1094 } 1095 } 1096 return best; 1097} 1098 1099/* 1100 * Issue a new request to a drive from hwgroup 1101 * Caller must have already done spin_lock_irqsave(&ide_lock, ..); 1102 * 1103 * A hwgroup is a serialized group of IDE interfaces. Usually there is 1104 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) 1105 * may have both interfaces in a single hwgroup to "serialize" access. 1106 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped 1107 * together into one hwgroup for serialized access. 1108 * 1109 * Note also that several hwgroups can end up sharing a single IRQ, 1110 * possibly along with many other devices. This is especially common in 1111 * PCI-based systems with off-board IDE controller cards. 1112 * 1113 * The IDE driver uses the single global ide_lock spinlock to protect 1114 * access to the request queues, and to protect the hwgroup->busy flag. 1115 * 1116 * The first thread into the driver for a particular hwgroup sets the 1117 * hwgroup->busy flag to indicate that this hwgroup is now active, 1118 * and then initiates processing of the top request from the request queue. 1119 * 1120 * Other threads attempting entry notice the busy setting, and will simply 1121 * queue their new requests and exit immediately. Note that hwgroup->busy 1122 * remains set even when the driver is merely awaiting the next interrupt. 1123 * Thus, the meaning is "this hwgroup is busy processing a request". 1124 * 1125 * When processing of a request completes, the completing thread or IRQ-handler 1126 * will start the next request from the queue. If no more work remains, 1127 * the driver will clear the hwgroup->busy flag and exit. 1128 * 1129 * The ide_lock (spinlock) is used to protect all access to the 1130 * hwgroup->busy flag, but is otherwise not needed for most processing in 1131 * the driver. This makes the driver much more friendlier to shared IRQs 1132 * than previous designs, while remaining 100% (?) SMP safe and capable. 1133 */ 1134static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) 1135{ 1136 ide_drive_t *drive; 1137 ide_hwif_t *hwif; 1138 struct request *rq; 1139 ide_startstop_t startstop; 1140 int loops = 0; 1141 1142 /* for atari only: POSSIBLY BROKEN HERE(?) */ 1143 ide_get_lock(ide_intr, hwgroup); 1144 1145 /* caller must own ide_lock */ 1146 BUG_ON(!irqs_disabled()); 1147 1148 while (!hwgroup->busy) { 1149 hwgroup->busy = 1; 1150 drive = choose_drive(hwgroup); 1151 if (drive == NULL) { 1152 int sleeping = 0; 1153 unsigned long sleep = 0; /* shut up, gcc */ 1154 hwgroup->rq = NULL; 1155 drive = hwgroup->drive; 1156 do { 1157 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { 1158 sleeping = 1; 1159 sleep = drive->sleep; 1160 } 1161 } while ((drive = drive->next) != hwgroup->drive); 1162 if (sleeping) { 1163 /* 1164 * Take a short snooze, and then wake up this hwgroup again. 1165 * This gives other hwgroups on the same a chance to 1166 * play fairly with us, just in case there are big differences 1167 * in relative throughputs.. don't want to hog the cpu too much. 1168 */ 1169 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) 1170 sleep = jiffies + WAIT_MIN_SLEEP; 1171#if 1 1172 if (timer_pending(&hwgroup->timer)) 1173 printk(KERN_CRIT "ide_set_handler: timer already active\n"); 1174#endif 1175 /* so that ide_timer_expiry knows what to do */ 1176 hwgroup->sleeping = 1; 1177 hwgroup->req_gen_timer = hwgroup->req_gen; 1178 mod_timer(&hwgroup->timer, sleep); 1179 /* we purposely leave hwgroup->busy==1 1180 * while sleeping */ 1181 } else { 1182 /* Ugly, but how can we sleep for the lock 1183 * otherwise? perhaps from tq_disk? 1184 */ 1185 1186 /* for atari only */ 1187 ide_release_lock(); 1188 hwgroup->busy = 0; 1189 } 1190 1191 /* no more work for this hwgroup (for now) */ 1192 return; 1193 } 1194 again: 1195 hwif = HWIF(drive); 1196 if (hwgroup->hwif->sharing_irq && 1197 hwif != hwgroup->hwif && 1198 hwif->io_ports[IDE_CONTROL_OFFSET]) { 1199 /* 1200 * set nIEN for previous hwif, drives in the 1201 * quirk_list may not like intr setups/cleanups 1202 */ 1203 if (drive->quirk_list != 1) 1204 hwif->OUTB(drive->ctl | 2, IDE_CONTROL_REG); 1205 } 1206 hwgroup->hwif = hwif; 1207 hwgroup->drive = drive; 1208 drive->sleeping = 0; 1209 drive->service_start = jiffies; 1210 1211 if (blk_queue_plugged(drive->queue)) { 1212 printk(KERN_ERR "ide: huh? queue was plugged!\n"); 1213 break; 1214 } 1215 1216 /* 1217 * we know that the queue isn't empty, but this can happen 1218 * if the q->prep_rq_fn() decides to kill a request 1219 */ 1220 rq = elv_next_request(drive->queue); 1221 if (!rq) { 1222 hwgroup->busy = 0; 1223 break; 1224 } 1225 1226 /* 1227 * Sanity: don't accept a request that isn't a PM request 1228 * if we are currently power managed. This is very important as 1229 * blk_stop_queue() doesn't prevent the elv_next_request() 1230 * above to return us whatever is in the queue. Since we call 1231 * ide_do_request() ourselves, we end up taking requests while 1232 * the queue is blocked... 1233 * 1234 * We let requests forced at head of queue with ide-preempt 1235 * though. I hope that doesn't happen too much, hopefully not 1236 * unless the subdriver triggers such a thing in its own PM 1237 * state machine. 1238 * 1239 * We count how many times we loop here to make sure we service 1240 * all drives in the hwgroup without looping for ever 1241 */ 1242 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) { 1243 drive = drive->next ? drive->next : hwgroup->drive; 1244 if (loops++ < 4 && !blk_queue_plugged(drive->queue)) 1245 goto again; 1246 /* We clear busy, there should be no pending ATA command at this point. */ 1247 hwgroup->busy = 0; 1248 break; 1249 } 1250 1251 hwgroup->rq = rq; 1252 1253 /* 1254 * Some systems have trouble with IDE IRQs arriving while 1255 * the driver is still setting things up. So, here we disable 1256 * the IRQ used by this interface while the request is being started. 1257 * This may look bad at first, but pretty much the same thing 1258 * happens anyway when any interrupt comes in, IDE or otherwise 1259 * -- the kernel masks the IRQ while it is being handled. 1260 */ 1261 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1262 disable_irq_nosync(hwif->irq); 1263 spin_unlock(&ide_lock); 1264 local_irq_enable_in_hardirq(); 1265 /* allow other IRQs while we start this request */ 1266 startstop = start_request(drive, rq); 1267 spin_lock_irq(&ide_lock); 1268 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1269 enable_irq(hwif->irq); 1270 if (startstop == ide_stopped) 1271 hwgroup->busy = 0; 1272 } 1273} 1274 1275/* 1276 * Passes the stuff to ide_do_request 1277 */ 1278void do_ide_request(struct request_queue *q) 1279{ 1280 ide_drive_t *drive = q->queuedata; 1281 1282 ide_do_request(HWGROUP(drive), IDE_NO_IRQ); 1283} 1284 1285/* 1286 * un-busy the hwgroup etc, and clear any pending DMA status. we want to 1287 * retry the current request in pio mode instead of risking tossing it 1288 * all away 1289 */ 1290static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) 1291{ 1292 ide_hwif_t *hwif = HWIF(drive); 1293 struct request *rq; 1294 ide_startstop_t ret = ide_stopped; 1295 1296 /* 1297 * end current dma transaction 1298 */ 1299 1300 if (error < 0) { 1301 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); 1302 (void)HWIF(drive)->ide_dma_end(drive); 1303 ret = ide_error(drive, "dma timeout error", 1304 hwif->INB(IDE_STATUS_REG)); 1305 } else { 1306 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); 1307 hwif->dma_timeout(drive); 1308 } 1309 1310 /* 1311 * disable dma for now, but remember that we did so because of 1312 * a timeout -- we'll reenable after we finish this next request 1313 * (or rather the first chunk of it) in pio. 1314 */ 1315 drive->retry_pio++; 1316 drive->state = DMA_PIO_RETRY; 1317 hwif->dma_off_quietly(drive); 1318 1319 /* 1320 * un-busy drive etc (hwgroup->busy is cleared on return) and 1321 * make sure request is sane 1322 */ 1323 rq = HWGROUP(drive)->rq; 1324 1325 if (!rq) 1326 goto out; 1327 1328 HWGROUP(drive)->rq = NULL; 1329 1330 rq->errors = 0; 1331 1332 if (!rq->bio) 1333 goto out; 1334 1335 rq->sector = rq->bio->bi_sector; 1336 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; 1337 rq->hard_cur_sectors = rq->current_nr_sectors; 1338 rq->buffer = bio_data(rq->bio); 1339out: 1340 return ret; 1341} 1342 1343/** 1344 * ide_timer_expiry - handle lack of an IDE interrupt 1345 * @data: timer callback magic (hwgroup) 1346 * 1347 * An IDE command has timed out before the expected drive return 1348 * occurred. At this point we attempt to clean up the current 1349 * mess. If the current handler includes an expiry handler then 1350 * we invoke the expiry handler, and providing it is happy the 1351 * work is done. If that fails we apply generic recovery rules 1352 * invoking the handler and checking the drive DMA status. We 1353 * have an excessively incestuous relationship with the DMA 1354 * logic that wants cleaning up. 1355 */ 1356 1357void ide_timer_expiry (unsigned long data) 1358{ 1359 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; 1360 ide_handler_t *handler; 1361 ide_expiry_t *expiry; 1362 unsigned long flags; 1363 unsigned long wait = -1; 1364 1365 spin_lock_irqsave(&ide_lock, flags); 1366 1367 if (((handler = hwgroup->handler) == NULL) || 1368 (hwgroup->req_gen != hwgroup->req_gen_timer)) { 1369 /* 1370 * Either a marginal timeout occurred 1371 * (got the interrupt just as timer expired), 1372 * or we were "sleeping" to give other devices a chance. 1373 * Either way, we don't really want to complain about anything. 1374 */ 1375 if (hwgroup->sleeping) { 1376 hwgroup->sleeping = 0; 1377 hwgroup->busy = 0; 1378 } 1379 } else { 1380 ide_drive_t *drive = hwgroup->drive; 1381 if (!drive) { 1382 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); 1383 hwgroup->handler = NULL; 1384 } else { 1385 ide_hwif_t *hwif; 1386 ide_startstop_t startstop = ide_stopped; 1387 if (!hwgroup->busy) { 1388 hwgroup->busy = 1; /* paranoia */ 1389 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); 1390 } 1391 if ((expiry = hwgroup->expiry) != NULL) { 1392 /* continue */ 1393 if ((wait = expiry(drive)) > 0) { 1394 /* reset timer */ 1395 hwgroup->timer.expires = jiffies + wait; 1396 hwgroup->req_gen_timer = hwgroup->req_gen; 1397 add_timer(&hwgroup->timer); 1398 spin_unlock_irqrestore(&ide_lock, flags); 1399 return; 1400 } 1401 } 1402 hwgroup->handler = NULL; 1403 /* 1404 * We need to simulate a real interrupt when invoking 1405 * the handler() function, which means we need to 1406 * globally mask the specific IRQ: 1407 */ 1408 spin_unlock(&ide_lock); 1409 hwif = HWIF(drive); 1410 /* disable_irq_nosync ?? */ 1411 disable_irq(hwif->irq); 1412 /* local CPU only, 1413 * as if we were handling an interrupt */ 1414 local_irq_disable(); 1415 if (hwgroup->polling) { 1416 startstop = handler(drive); 1417 } else if (drive_is_ready(drive)) { 1418 if (drive->waiting_for_dma) 1419 hwgroup->hwif->dma_lost_irq(drive); 1420 (void)ide_ack_intr(hwif); 1421 printk(KERN_WARNING "%s: lost interrupt\n", drive->name); 1422 startstop = handler(drive); 1423 } else { 1424 if (drive->waiting_for_dma) { 1425 startstop = ide_dma_timeout_retry(drive, wait); 1426 } else 1427 startstop = 1428 ide_error(drive, "irq timeout", hwif->INB(IDE_STATUS_REG)); 1429 } 1430 drive->service_time = jiffies - drive->service_start; 1431 spin_lock_irq(&ide_lock); 1432 enable_irq(hwif->irq); 1433 if (startstop == ide_stopped) 1434 hwgroup->busy = 0; 1435 } 1436 } 1437 ide_do_request(hwgroup, IDE_NO_IRQ); 1438 spin_unlock_irqrestore(&ide_lock, flags); 1439} 1440 1441/** 1442 * unexpected_intr - handle an unexpected IDE interrupt 1443 * @irq: interrupt line 1444 * @hwgroup: hwgroup being processed 1445 * 1446 * There's nothing really useful we can do with an unexpected interrupt, 1447 * other than reading the status register (to clear it), and logging it. 1448 * There should be no way that an irq can happen before we're ready for it, 1449 * so we needn't worry much about losing an "important" interrupt here. 1450 * 1451 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever 1452 * the drive enters "idle", "standby", or "sleep" mode, so if the status 1453 * looks "good", we just ignore the interrupt completely. 1454 * 1455 * This routine assumes __cli() is in effect when called. 1456 * 1457 * If an unexpected interrupt happens on irq15 while we are handling irq14 1458 * and if the two interfaces are "serialized" (CMD640), then it looks like 1459 * we could screw up by interfering with a new request being set up for 1460 * irq15. 1461 * 1462 * In reality, this is a non-issue. The new command is not sent unless 1463 * the drive is ready to accept one, in which case we know the drive is 1464 * not trying to interrupt us. And ide_set_handler() is always invoked 1465 * before completing the issuance of any new drive command, so we will not 1466 * be accidentally invoked as a result of any valid command completion 1467 * interrupt. 1468 * 1469 * Note that we must walk the entire hwgroup here. We know which hwif 1470 * is doing the current command, but we don't know which hwif burped 1471 * mysteriously. 1472 */ 1473 1474static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) 1475{ 1476 u8 stat; 1477 ide_hwif_t *hwif = hwgroup->hwif; 1478 1479 /* 1480 * handle the unexpected interrupt 1481 */ 1482 do { 1483 if (hwif->irq == irq) { 1484 stat = hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1485 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { 1486 /* Try to not flood the console with msgs */ 1487 static unsigned long last_msgtime, count; 1488 ++count; 1489 if (time_after(jiffies, last_msgtime + HZ)) { 1490 last_msgtime = jiffies; 1491 printk(KERN_ERR "%s%s: unexpected interrupt, " 1492 "status=0x%02x, count=%ld\n", 1493 hwif->name, 1494 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); 1495 } 1496 } 1497 } 1498 } while ((hwif = hwif->next) != hwgroup->hwif); 1499} 1500 1501/** 1502 * ide_intr - default IDE interrupt handler 1503 * @irq: interrupt number 1504 * @dev_id: hwif group 1505 * @regs: unused weirdness from the kernel irq layer 1506 * 1507 * This is the default IRQ handler for the IDE layer. You should 1508 * not need to override it. If you do be aware it is subtle in 1509 * places 1510 * 1511 * hwgroup->hwif is the interface in the group currently performing 1512 * a command. hwgroup->drive is the drive and hwgroup->handler is 1513 * the IRQ handler to call. As we issue a command the handlers 1514 * step through multiple states, reassigning the handler to the 1515 * next step in the process. Unlike a smart SCSI controller IDE 1516 * expects the main processor to sequence the various transfer 1517 * stages. We also manage a poll timer to catch up with most 1518 * timeout situations. There are still a few where the handlers 1519 * don't ever decide to give up. 1520 * 1521 * The handler eventually returns ide_stopped to indicate the 1522 * request completed. At this point we issue the next request 1523 * on the hwgroup and the process begins again. 1524 */ 1525 1526irqreturn_t ide_intr (int irq, void *dev_id) 1527{ 1528 unsigned long flags; 1529 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; 1530 ide_hwif_t *hwif; 1531 ide_drive_t *drive; 1532 ide_handler_t *handler; 1533 ide_startstop_t startstop; 1534 1535 spin_lock_irqsave(&ide_lock, flags); 1536 hwif = hwgroup->hwif; 1537 1538 if (!ide_ack_intr(hwif)) { 1539 spin_unlock_irqrestore(&ide_lock, flags); 1540 return IRQ_NONE; 1541 } 1542 1543 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { 1544 /* 1545 * Not expecting an interrupt from this drive. 1546 * That means this could be: 1547 * (1) an interrupt from another PCI device 1548 * sharing the same PCI INT# as us. 1549 * or (2) a drive just entered sleep or standby mode, 1550 * and is interrupting to let us know. 1551 * or (3) a spurious interrupt of unknown origin. 1552 * 1553 * For PCI, we cannot tell the difference, 1554 * so in that case we just ignore it and hope it goes away. 1555 * 1556 * FIXME: unexpected_intr should be hwif-> then we can 1557 * remove all the ifdef PCI crap 1558 */ 1559#ifdef CONFIG_BLK_DEV_IDEPCI 1560 if (hwif->pci_dev && !hwif->pci_dev->vendor) 1561#endif /* CONFIG_BLK_DEV_IDEPCI */ 1562 { 1563 /* 1564 * Probably not a shared PCI interrupt, 1565 * so we can safely try to do something about it: 1566 */ 1567 unexpected_intr(irq, hwgroup); 1568#ifdef CONFIG_BLK_DEV_IDEPCI 1569 } else { 1570 /* 1571 * Whack the status register, just in case 1572 * we have a leftover pending IRQ. 1573 */ 1574 (void) hwif->INB(hwif->io_ports[IDE_STATUS_OFFSET]); 1575#endif /* CONFIG_BLK_DEV_IDEPCI */ 1576 } 1577 spin_unlock_irqrestore(&ide_lock, flags); 1578 return IRQ_NONE; 1579 } 1580 drive = hwgroup->drive; 1581 if (!drive) { 1582 /* 1583 * This should NEVER happen, and there isn't much 1584 * we could do about it here. 1585 * 1586 * [Note - this can occur if the drive is hot unplugged] 1587 */ 1588 spin_unlock_irqrestore(&ide_lock, flags); 1589 return IRQ_HANDLED; 1590 } 1591 if (!drive_is_ready(drive)) { 1592 /* 1593 * This happens regularly when we share a PCI IRQ with 1594 * another device. Unfortunately, it can also happen 1595 * with some buggy drives that trigger the IRQ before 1596 * their status register is up to date. Hopefully we have 1597 * enough advance overhead that the latter isn't a problem. 1598 */ 1599 spin_unlock_irqrestore(&ide_lock, flags); 1600 return IRQ_NONE; 1601 } 1602 if (!hwgroup->busy) { 1603 hwgroup->busy = 1; /* paranoia */ 1604 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); 1605 } 1606 hwgroup->handler = NULL; 1607 hwgroup->req_gen++; 1608 del_timer(&hwgroup->timer); 1609 spin_unlock(&ide_lock); 1610 1611 /* Some controllers might set DMA INTR no matter DMA or PIO; 1612 * bmdma status might need to be cleared even for 1613 * PIO interrupts to prevent spurious/lost irq. 1614 */ 1615 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma)) 1616 /* ide_dma_end() needs bmdma status for error checking. 1617 * So, skip clearing bmdma status here and leave it 1618 * to ide_dma_end() if this is dma interrupt. 1619 */ 1620 hwif->ide_dma_clear_irq(drive); 1621 1622 if (drive->unmask) 1623 local_irq_enable_in_hardirq(); 1624 /* service this interrupt, may set handler for next interrupt */ 1625 startstop = handler(drive); 1626 spin_lock_irq(&ide_lock); 1627 1628 /* 1629 * Note that handler() may have set things up for another 1630 * interrupt to occur soon, but it cannot happen until 1631 * we exit from this routine, because it will be the 1632 * same irq as is currently being serviced here, and Linux 1633 * won't allow another of the same (on any CPU) until we return. 1634 */ 1635 drive->service_time = jiffies - drive->service_start; 1636 if (startstop == ide_stopped) { 1637 if (hwgroup->handler == NULL) { /* paranoia */ 1638 hwgroup->busy = 0; 1639 ide_do_request(hwgroup, hwif->irq); 1640 } else { 1641 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " 1642 "on exit\n", drive->name); 1643 } 1644 } 1645 spin_unlock_irqrestore(&ide_lock, flags); 1646 return IRQ_HANDLED; 1647} 1648 1649/** 1650 * ide_init_drive_cmd - initialize a drive command request 1651 * @rq: request object 1652 * 1653 * Initialize a request before we fill it in and send it down to 1654 * ide_do_drive_cmd. Commands must be set up by this function. Right 1655 * now it doesn't do a lot, but if that changes abusers will have a 1656 * nasty surprise. 1657 */ 1658 1659void ide_init_drive_cmd (struct request *rq) 1660{ 1661 memset(rq, 0, sizeof(*rq)); 1662 rq->cmd_type = REQ_TYPE_ATA_CMD; 1663 rq->ref_count = 1; 1664} 1665 1666EXPORT_SYMBOL(ide_init_drive_cmd); 1667 1668/** 1669 * ide_do_drive_cmd - issue IDE special command 1670 * @drive: device to issue command 1671 * @rq: request to issue 1672 * @action: action for processing 1673 * 1674 * This function issues a special IDE device request 1675 * onto the request queue. 1676 * 1677 * If action is ide_wait, then the rq is queued at the end of the 1678 * request queue, and the function sleeps until it has been processed. 1679 * This is for use when invoked from an ioctl handler. 1680 * 1681 * If action is ide_preempt, then the rq is queued at the head of 1682 * the request queue, displacing the currently-being-processed 1683 * request and this function returns immediately without waiting 1684 * for the new rq to be completed. This is VERY DANGEROUS, and is 1685 * intended for careful use by the ATAPI tape/cdrom driver code. 1686 * 1687 * If action is ide_end, then the rq is queued at the end of the 1688 * request queue, and the function returns immediately without waiting 1689 * for the new rq to be completed. This is again intended for careful 1690 * use by the ATAPI tape/cdrom driver code. 1691 */ 1692 1693int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) 1694{ 1695 unsigned long flags; 1696 ide_hwgroup_t *hwgroup = HWGROUP(drive); 1697 DECLARE_COMPLETION_ONSTACK(wait); 1698 int where = ELEVATOR_INSERT_BACK, err; 1699 int must_wait = (action == ide_wait || action == ide_head_wait); 1700 1701 rq->errors = 0; 1702 1703 /* 1704 * we need to hold an extra reference to request for safe inspection 1705 * after completion 1706 */ 1707 if (must_wait) { 1708 rq->ref_count++; 1709 rq->end_io_data = &wait; 1710 rq->end_io = blk_end_sync_rq; 1711 } 1712 1713 spin_lock_irqsave(&ide_lock, flags); 1714 if (action == ide_preempt) 1715 hwgroup->rq = NULL; 1716 if (action == ide_preempt || action == ide_head_wait) { 1717 where = ELEVATOR_INSERT_FRONT; 1718 rq->cmd_flags |= REQ_PREEMPT; 1719 } 1720 __elv_add_request(drive->queue, rq, where, 0); 1721 ide_do_request(hwgroup, IDE_NO_IRQ); 1722 spin_unlock_irqrestore(&ide_lock, flags); 1723 1724 err = 0; 1725 if (must_wait) { 1726 wait_for_completion(&wait); 1727 if (rq->errors) 1728 err = -EIO; 1729 1730 blk_put_request(rq); 1731 } 1732 1733 return err; 1734} 1735 1736EXPORT_SYMBOL(ide_do_drive_cmd); 1737 1738void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma) 1739{ 1740 ide_task_t task; 1741 1742 memset(&task, 0, sizeof(task)); 1743 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM | 1744 IDE_TFLAG_OUT_FEATURE | tf_flags; 1745 task.tf.feature = dma; /* Use PIO/DMA */ 1746 task.tf.lbam = bcount & 0xff; 1747 task.tf.lbah = (bcount >> 8) & 0xff; 1748 1749 ide_tf_load(drive, &task); 1750} 1751 1752EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load); 1753