ide-io.c revision f8c4bd0ab2b8783c0f080957781e9f70bee48eaa
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 int error = 0; 62 63 if (uptodate <= 0) 64 error = uptodate ? uptodate : -EIO; 65 66 /* 67 * if failfast is set on a request, override number of sectors and 68 * complete the whole request right now 69 */ 70 if (blk_noretry_request(rq) && error) 71 nr_bytes = rq->hard_nr_sectors << 9; 72 73 if (!blk_fs_request(rq) && error && !rq->errors) 74 rq->errors = -EIO; 75 76 /* 77 * decide whether to reenable DMA -- 3 is a random magic for now, 78 * if we DMA timeout more than 3 times, just stay in PIO 79 */ 80 if (drive->state == DMA_PIO_RETRY && drive->retry_pio <= 3) { 81 drive->state = 0; 82 ide_dma_on(drive); 83 } 84 85 if (!__blk_end_request(rq, error, nr_bytes)) { 86 if (dequeue) 87 HWGROUP(drive)->rq = NULL; 88 ret = 0; 89 } 90 91 return ret; 92} 93 94/** 95 * ide_end_request - complete an IDE I/O 96 * @drive: IDE device for the I/O 97 * @uptodate: 98 * @nr_sectors: number of sectors completed 99 * 100 * This is our end_request wrapper function. We complete the I/O 101 * update random number input and dequeue the request, which if 102 * it was tagged may be out of order. 103 */ 104 105int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors) 106{ 107 unsigned int nr_bytes = nr_sectors << 9; 108 struct request *rq; 109 unsigned long flags; 110 int ret = 1; 111 112 /* 113 * room for locking improvements here, the calls below don't 114 * need the queue lock held at all 115 */ 116 spin_lock_irqsave(&ide_lock, flags); 117 rq = HWGROUP(drive)->rq; 118 119 if (!nr_bytes) { 120 if (blk_pc_request(rq)) 121 nr_bytes = rq->data_len; 122 else 123 nr_bytes = rq->hard_cur_sectors << 9; 124 } 125 126 ret = __ide_end_request(drive, rq, uptodate, nr_bytes, 1); 127 128 spin_unlock_irqrestore(&ide_lock, flags); 129 return ret; 130} 131EXPORT_SYMBOL(ide_end_request); 132 133/* 134 * Power Management state machine. This one is rather trivial for now, 135 * we should probably add more, like switching back to PIO on suspend 136 * to help some BIOSes, re-do the door locking on resume, etc... 137 */ 138 139enum { 140 ide_pm_flush_cache = ide_pm_state_start_suspend, 141 idedisk_pm_standby, 142 143 idedisk_pm_restore_pio = ide_pm_state_start_resume, 144 idedisk_pm_idle, 145 ide_pm_restore_dma, 146}; 147 148static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error) 149{ 150 struct request_pm_state *pm = rq->data; 151 152 if (drive->media != ide_disk) 153 return; 154 155 switch (pm->pm_step) { 156 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) complete */ 157 if (pm->pm_state == PM_EVENT_FREEZE) 158 pm->pm_step = ide_pm_state_completed; 159 else 160 pm->pm_step = idedisk_pm_standby; 161 break; 162 case idedisk_pm_standby: /* Suspend step 2 (standby) complete */ 163 pm->pm_step = ide_pm_state_completed; 164 break; 165 case idedisk_pm_restore_pio: /* Resume step 1 complete */ 166 pm->pm_step = idedisk_pm_idle; 167 break; 168 case idedisk_pm_idle: /* Resume step 2 (idle) complete */ 169 pm->pm_step = ide_pm_restore_dma; 170 break; 171 } 172} 173 174static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq) 175{ 176 struct request_pm_state *pm = rq->data; 177 ide_task_t *args = rq->special; 178 179 memset(args, 0, sizeof(*args)); 180 181 switch (pm->pm_step) { 182 case ide_pm_flush_cache: /* Suspend step 1 (flush cache) */ 183 if (drive->media != ide_disk) 184 break; 185 /* Not supported? Switch to next step now. */ 186 if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) { 187 ide_complete_power_step(drive, rq, 0, 0); 188 return ide_stopped; 189 } 190 if (ide_id_has_flush_cache_ext(drive->id)) 191 args->tf.command = WIN_FLUSH_CACHE_EXT; 192 else 193 args->tf.command = WIN_FLUSH_CACHE; 194 goto out_do_tf; 195 196 case idedisk_pm_standby: /* Suspend step 2 (standby) */ 197 args->tf.command = WIN_STANDBYNOW1; 198 goto out_do_tf; 199 200 case idedisk_pm_restore_pio: /* Resume step 1 (restore PIO) */ 201 ide_set_max_pio(drive); 202 /* 203 * skip idedisk_pm_idle for ATAPI devices 204 */ 205 if (drive->media != ide_disk) 206 pm->pm_step = ide_pm_restore_dma; 207 else 208 ide_complete_power_step(drive, rq, 0, 0); 209 return ide_stopped; 210 211 case idedisk_pm_idle: /* Resume step 2 (idle) */ 212 args->tf.command = WIN_IDLEIMMEDIATE; 213 goto out_do_tf; 214 215 case ide_pm_restore_dma: /* Resume step 3 (restore DMA) */ 216 /* 217 * Right now, all we do is call ide_set_dma(drive), 218 * we could be smarter and check for current xfer_speed 219 * in struct drive etc... 220 */ 221 if (drive->hwif->dma_ops == NULL) 222 break; 223 /* 224 * TODO: respect ->using_dma setting 225 */ 226 ide_set_dma(drive); 227 break; 228 } 229 pm->pm_step = ide_pm_state_completed; 230 return ide_stopped; 231 232out_do_tf: 233 args->tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE; 234 args->data_phase = TASKFILE_NO_DATA; 235 return do_rw_taskfile(drive, args); 236} 237 238/** 239 * ide_end_dequeued_request - complete an IDE I/O 240 * @drive: IDE device for the I/O 241 * @uptodate: 242 * @nr_sectors: number of sectors completed 243 * 244 * Complete an I/O that is no longer on the request queue. This 245 * typically occurs when we pull the request and issue a REQUEST_SENSE. 246 * We must still finish the old request but we must not tamper with the 247 * queue in the meantime. 248 * 249 * NOTE: This path does not handle barrier, but barrier is not supported 250 * on ide-cd anyway. 251 */ 252 253int ide_end_dequeued_request(ide_drive_t *drive, struct request *rq, 254 int uptodate, int nr_sectors) 255{ 256 unsigned long flags; 257 int ret; 258 259 spin_lock_irqsave(&ide_lock, flags); 260 BUG_ON(!blk_rq_started(rq)); 261 ret = __ide_end_request(drive, rq, uptodate, nr_sectors << 9, 0); 262 spin_unlock_irqrestore(&ide_lock, flags); 263 264 return ret; 265} 266EXPORT_SYMBOL_GPL(ide_end_dequeued_request); 267 268 269/** 270 * ide_complete_pm_request - end the current Power Management request 271 * @drive: target drive 272 * @rq: request 273 * 274 * This function cleans up the current PM request and stops the queue 275 * if necessary. 276 */ 277static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq) 278{ 279 unsigned long flags; 280 281#ifdef DEBUG_PM 282 printk("%s: completing PM request, %s\n", drive->name, 283 blk_pm_suspend_request(rq) ? "suspend" : "resume"); 284#endif 285 spin_lock_irqsave(&ide_lock, flags); 286 if (blk_pm_suspend_request(rq)) { 287 blk_stop_queue(drive->queue); 288 } else { 289 drive->blocked = 0; 290 blk_start_queue(drive->queue); 291 } 292 HWGROUP(drive)->rq = NULL; 293 if (__blk_end_request(rq, 0, 0)) 294 BUG(); 295 spin_unlock_irqrestore(&ide_lock, flags); 296} 297 298/** 299 * ide_end_drive_cmd - end an explicit drive command 300 * @drive: command 301 * @stat: status bits 302 * @err: error bits 303 * 304 * Clean up after success/failure of an explicit drive command. 305 * These get thrown onto the queue so they are synchronized with 306 * real I/O operations on the drive. 307 * 308 * In LBA48 mode we have to read the register set twice to get 309 * all the extra information out. 310 */ 311 312void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err) 313{ 314 unsigned long flags; 315 struct request *rq; 316 317 spin_lock_irqsave(&ide_lock, flags); 318 rq = HWGROUP(drive)->rq; 319 spin_unlock_irqrestore(&ide_lock, flags); 320 321 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) { 322 ide_task_t *task = (ide_task_t *)rq->special; 323 324 if (rq->errors == 0) 325 rq->errors = !OK_STAT(stat, READY_STAT, BAD_STAT); 326 327 if (task) { 328 struct ide_taskfile *tf = &task->tf; 329 330 tf->error = err; 331 tf->status = stat; 332 333 drive->hwif->tf_read(drive, task); 334 335 if (task->tf_flags & IDE_TFLAG_DYN) 336 kfree(task); 337 } 338 } else if (blk_pm_request(rq)) { 339 struct request_pm_state *pm = rq->data; 340#ifdef DEBUG_PM 341 printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n", 342 drive->name, rq->pm->pm_step, stat, err); 343#endif 344 ide_complete_power_step(drive, rq, stat, err); 345 if (pm->pm_step == ide_pm_state_completed) 346 ide_complete_pm_request(drive, rq); 347 return; 348 } 349 350 spin_lock_irqsave(&ide_lock, flags); 351 HWGROUP(drive)->rq = NULL; 352 rq->errors = err; 353 if (unlikely(__blk_end_request(rq, (rq->errors ? -EIO : 0), 354 blk_rq_bytes(rq)))) 355 BUG(); 356 spin_unlock_irqrestore(&ide_lock, flags); 357} 358 359EXPORT_SYMBOL(ide_end_drive_cmd); 360 361static void ide_kill_rq(ide_drive_t *drive, struct request *rq) 362{ 363 if (rq->rq_disk) { 364 ide_driver_t *drv; 365 366 drv = *(ide_driver_t **)rq->rq_disk->private_data; 367 drv->end_request(drive, 0, 0); 368 } else 369 ide_end_request(drive, 0, 0); 370} 371 372static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 373{ 374 ide_hwif_t *hwif = drive->hwif; 375 376 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 377 /* other bits are useless when BUSY */ 378 rq->errors |= ERROR_RESET; 379 } else if (stat & ERR_STAT) { 380 /* err has different meaning on cdrom and tape */ 381 if (err == ABRT_ERR) { 382 if (drive->select.b.lba && 383 /* some newer drives don't support WIN_SPECIFY */ 384 hwif->INB(hwif->io_ports.command_addr) == 385 WIN_SPECIFY) 386 return ide_stopped; 387 } else if ((err & BAD_CRC) == BAD_CRC) { 388 /* UDMA crc error, just retry the operation */ 389 drive->crc_count++; 390 } else if (err & (BBD_ERR | ECC_ERR)) { 391 /* retries won't help these */ 392 rq->errors = ERROR_MAX; 393 } else if (err & TRK0_ERR) { 394 /* help it find track zero */ 395 rq->errors |= ERROR_RECAL; 396 } 397 } 398 399 if ((stat & DRQ_STAT) && rq_data_dir(rq) == READ && 400 (hwif->host_flags & IDE_HFLAG_ERROR_STOPS_FIFO) == 0) { 401 int nsect = drive->mult_count ? drive->mult_count : 1; 402 403 ide_pad_transfer(drive, READ, nsect * SECTOR_SIZE); 404 } 405 406 if (rq->errors >= ERROR_MAX || blk_noretry_request(rq)) { 407 ide_kill_rq(drive, rq); 408 return ide_stopped; 409 } 410 411 if (ide_read_status(drive) & (BUSY_STAT | DRQ_STAT)) 412 rq->errors |= ERROR_RESET; 413 414 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 415 ++rq->errors; 416 return ide_do_reset(drive); 417 } 418 419 if ((rq->errors & ERROR_RECAL) == ERROR_RECAL) 420 drive->special.b.recalibrate = 1; 421 422 ++rq->errors; 423 424 return ide_stopped; 425} 426 427static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 428{ 429 ide_hwif_t *hwif = drive->hwif; 430 431 if (stat & BUSY_STAT || ((stat & WRERR_STAT) && !drive->nowerr)) { 432 /* other bits are useless when BUSY */ 433 rq->errors |= ERROR_RESET; 434 } else { 435 /* add decoding error stuff */ 436 } 437 438 if (ide_read_status(drive) & (BUSY_STAT | DRQ_STAT)) 439 /* force an abort */ 440 hwif->OUTBSYNC(hwif, WIN_IDLEIMMEDIATE, 441 hwif->io_ports.command_addr); 442 443 if (rq->errors >= ERROR_MAX) { 444 ide_kill_rq(drive, rq); 445 } else { 446 if ((rq->errors & ERROR_RESET) == ERROR_RESET) { 447 ++rq->errors; 448 return ide_do_reset(drive); 449 } 450 ++rq->errors; 451 } 452 453 return ide_stopped; 454} 455 456ide_startstop_t 457__ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err) 458{ 459 if (drive->media == ide_disk) 460 return ide_ata_error(drive, rq, stat, err); 461 return ide_atapi_error(drive, rq, stat, err); 462} 463 464EXPORT_SYMBOL_GPL(__ide_error); 465 466/** 467 * ide_error - handle an error on the IDE 468 * @drive: drive the error occurred on 469 * @msg: message to report 470 * @stat: status bits 471 * 472 * ide_error() takes action based on the error returned by the drive. 473 * For normal I/O that may well include retries. We deal with 474 * both new-style (taskfile) and old style command handling here. 475 * In the case of taskfile command handling there is work left to 476 * do 477 */ 478 479ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat) 480{ 481 struct request *rq; 482 u8 err; 483 484 err = ide_dump_status(drive, msg, stat); 485 486 if ((rq = HWGROUP(drive)->rq) == NULL) 487 return ide_stopped; 488 489 /* retry only "normal" I/O: */ 490 if (!blk_fs_request(rq)) { 491 rq->errors = 1; 492 ide_end_drive_cmd(drive, stat, err); 493 return ide_stopped; 494 } 495 496 if (rq->rq_disk) { 497 ide_driver_t *drv; 498 499 drv = *(ide_driver_t **)rq->rq_disk->private_data; 500 return drv->error(drive, rq, stat, err); 501 } else 502 return __ide_error(drive, rq, stat, err); 503} 504 505EXPORT_SYMBOL_GPL(ide_error); 506 507ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq) 508{ 509 if (drive->media != ide_disk) 510 rq->errors |= ERROR_RESET; 511 512 ide_kill_rq(drive, rq); 513 514 return ide_stopped; 515} 516 517EXPORT_SYMBOL_GPL(__ide_abort); 518 519/** 520 * ide_abort - abort pending IDE operations 521 * @drive: drive the error occurred on 522 * @msg: message to report 523 * 524 * ide_abort kills and cleans up when we are about to do a 525 * host initiated reset on active commands. Longer term we 526 * want handlers to have sensible abort handling themselves 527 * 528 * This differs fundamentally from ide_error because in 529 * this case the command is doing just fine when we 530 * blow it away. 531 */ 532 533ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg) 534{ 535 struct request *rq; 536 537 if (drive == NULL || (rq = HWGROUP(drive)->rq) == NULL) 538 return ide_stopped; 539 540 /* retry only "normal" I/O: */ 541 if (!blk_fs_request(rq)) { 542 rq->errors = 1; 543 ide_end_drive_cmd(drive, BUSY_STAT, 0); 544 return ide_stopped; 545 } 546 547 if (rq->rq_disk) { 548 ide_driver_t *drv; 549 550 drv = *(ide_driver_t **)rq->rq_disk->private_data; 551 return drv->abort(drive, rq); 552 } else 553 return __ide_abort(drive, rq); 554} 555 556static void ide_tf_set_specify_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 557{ 558 tf->nsect = drive->sect; 559 tf->lbal = drive->sect; 560 tf->lbam = drive->cyl; 561 tf->lbah = drive->cyl >> 8; 562 tf->device = ((drive->head - 1) | drive->select.all) & ~ATA_LBA; 563 tf->command = WIN_SPECIFY; 564} 565 566static void ide_tf_set_restore_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 567{ 568 tf->nsect = drive->sect; 569 tf->command = WIN_RESTORE; 570} 571 572static void ide_tf_set_setmult_cmd(ide_drive_t *drive, struct ide_taskfile *tf) 573{ 574 tf->nsect = drive->mult_req; 575 tf->command = WIN_SETMULT; 576} 577 578static ide_startstop_t ide_disk_special(ide_drive_t *drive) 579{ 580 special_t *s = &drive->special; 581 ide_task_t args; 582 583 memset(&args, 0, sizeof(ide_task_t)); 584 args.data_phase = TASKFILE_NO_DATA; 585 586 if (s->b.set_geometry) { 587 s->b.set_geometry = 0; 588 ide_tf_set_specify_cmd(drive, &args.tf); 589 } else if (s->b.recalibrate) { 590 s->b.recalibrate = 0; 591 ide_tf_set_restore_cmd(drive, &args.tf); 592 } else if (s->b.set_multmode) { 593 s->b.set_multmode = 0; 594 if (drive->mult_req > drive->id->max_multsect) 595 drive->mult_req = drive->id->max_multsect; 596 ide_tf_set_setmult_cmd(drive, &args.tf); 597 } else if (s->all) { 598 int special = s->all; 599 s->all = 0; 600 printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special); 601 return ide_stopped; 602 } 603 604 args.tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE | 605 IDE_TFLAG_CUSTOM_HANDLER; 606 607 do_rw_taskfile(drive, &args); 608 609 return ide_started; 610} 611 612/* 613 * handle HDIO_SET_PIO_MODE ioctl abusers here, eventually it will go away 614 */ 615static int set_pio_mode_abuse(ide_hwif_t *hwif, u8 req_pio) 616{ 617 switch (req_pio) { 618 case 202: 619 case 201: 620 case 200: 621 case 102: 622 case 101: 623 case 100: 624 return (hwif->host_flags & IDE_HFLAG_ABUSE_DMA_MODES) ? 1 : 0; 625 case 9: 626 case 8: 627 return (hwif->host_flags & IDE_HFLAG_ABUSE_PREFETCH) ? 1 : 0; 628 case 7: 629 case 6: 630 return (hwif->host_flags & IDE_HFLAG_ABUSE_FAST_DEVSEL) ? 1 : 0; 631 default: 632 return 0; 633 } 634} 635 636/** 637 * do_special - issue some special commands 638 * @drive: drive the command is for 639 * 640 * do_special() is used to issue WIN_SPECIFY, WIN_RESTORE, and WIN_SETMULT 641 * commands to a drive. It used to do much more, but has been scaled 642 * back. 643 */ 644 645static ide_startstop_t do_special (ide_drive_t *drive) 646{ 647 special_t *s = &drive->special; 648 649#ifdef DEBUG 650 printk("%s: do_special: 0x%02x\n", drive->name, s->all); 651#endif 652 if (s->b.set_tune) { 653 ide_hwif_t *hwif = drive->hwif; 654 const struct ide_port_ops *port_ops = hwif->port_ops; 655 u8 req_pio = drive->tune_req; 656 657 s->b.set_tune = 0; 658 659 if (set_pio_mode_abuse(drive->hwif, req_pio)) { 660 /* 661 * take ide_lock for drive->[no_]unmask/[no_]io_32bit 662 */ 663 if (req_pio == 8 || req_pio == 9) { 664 unsigned long flags; 665 666 spin_lock_irqsave(&ide_lock, flags); 667 port_ops->set_pio_mode(drive, req_pio); 668 spin_unlock_irqrestore(&ide_lock, flags); 669 } else 670 port_ops->set_pio_mode(drive, req_pio); 671 } else { 672 int keep_dma = drive->using_dma; 673 674 ide_set_pio(drive, req_pio); 675 676 if (hwif->host_flags & IDE_HFLAG_SET_PIO_MODE_KEEP_DMA) { 677 if (keep_dma) 678 ide_dma_on(drive); 679 } 680 } 681 682 return ide_stopped; 683 } else { 684 if (drive->media == ide_disk) 685 return ide_disk_special(drive); 686 687 s->all = 0; 688 drive->mult_req = 0; 689 return ide_stopped; 690 } 691} 692 693void ide_map_sg(ide_drive_t *drive, struct request *rq) 694{ 695 ide_hwif_t *hwif = drive->hwif; 696 struct scatterlist *sg = hwif->sg_table; 697 698 if (hwif->sg_mapped) /* needed by ide-scsi */ 699 return; 700 701 if (rq->cmd_type != REQ_TYPE_ATA_TASKFILE) { 702 hwif->sg_nents = blk_rq_map_sg(drive->queue, rq, sg); 703 } else { 704 sg_init_one(sg, rq->buffer, rq->nr_sectors * SECTOR_SIZE); 705 hwif->sg_nents = 1; 706 } 707} 708 709EXPORT_SYMBOL_GPL(ide_map_sg); 710 711void ide_init_sg_cmd(ide_drive_t *drive, struct request *rq) 712{ 713 ide_hwif_t *hwif = drive->hwif; 714 715 hwif->nsect = hwif->nleft = rq->nr_sectors; 716 hwif->cursg_ofs = 0; 717 hwif->cursg = NULL; 718} 719 720EXPORT_SYMBOL_GPL(ide_init_sg_cmd); 721 722/** 723 * execute_drive_command - issue special drive command 724 * @drive: the drive to issue the command on 725 * @rq: the request structure holding the command 726 * 727 * execute_drive_cmd() issues a special drive command, usually 728 * initiated by ioctl() from the external hdparm program. The 729 * command can be a drive command, drive task or taskfile 730 * operation. Weirdly you can call it with NULL to wait for 731 * all commands to finish. Don't do this as that is due to change 732 */ 733 734static ide_startstop_t execute_drive_cmd (ide_drive_t *drive, 735 struct request *rq) 736{ 737 ide_hwif_t *hwif = HWIF(drive); 738 ide_task_t *task = rq->special; 739 740 if (task) { 741 hwif->data_phase = task->data_phase; 742 743 switch (hwif->data_phase) { 744 case TASKFILE_MULTI_OUT: 745 case TASKFILE_OUT: 746 case TASKFILE_MULTI_IN: 747 case TASKFILE_IN: 748 ide_init_sg_cmd(drive, rq); 749 ide_map_sg(drive, rq); 750 default: 751 break; 752 } 753 754 return do_rw_taskfile(drive, task); 755 } 756 757 /* 758 * NULL is actually a valid way of waiting for 759 * all current requests to be flushed from the queue. 760 */ 761#ifdef DEBUG 762 printk("%s: DRIVE_CMD (null)\n", drive->name); 763#endif 764 ide_end_drive_cmd(drive, ide_read_status(drive), ide_read_error(drive)); 765 766 return ide_stopped; 767} 768 769static void ide_check_pm_state(ide_drive_t *drive, struct request *rq) 770{ 771 struct request_pm_state *pm = rq->data; 772 773 if (blk_pm_suspend_request(rq) && 774 pm->pm_step == ide_pm_state_start_suspend) 775 /* Mark drive blocked when starting the suspend sequence. */ 776 drive->blocked = 1; 777 else if (blk_pm_resume_request(rq) && 778 pm->pm_step == ide_pm_state_start_resume) { 779 /* 780 * The first thing we do on wakeup is to wait for BSY bit to 781 * go away (with a looong timeout) as a drive on this hwif may 782 * just be POSTing itself. 783 * We do that before even selecting as the "other" device on 784 * the bus may be broken enough to walk on our toes at this 785 * point. 786 */ 787 int rc; 788#ifdef DEBUG_PM 789 printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name); 790#endif 791 rc = ide_wait_not_busy(HWIF(drive), 35000); 792 if (rc) 793 printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name); 794 SELECT_DRIVE(drive); 795 ide_set_irq(drive, 1); 796 rc = ide_wait_not_busy(HWIF(drive), 100000); 797 if (rc) 798 printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name); 799 } 800} 801 802/** 803 * start_request - start of I/O and command issuing for IDE 804 * 805 * start_request() initiates handling of a new I/O request. It 806 * accepts commands and I/O (read/write) requests. It also does 807 * the final remapping for weird stuff like EZDrive. Once 808 * device mapper can work sector level the EZDrive stuff can go away 809 * 810 * FIXME: this function needs a rename 811 */ 812 813static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq) 814{ 815 ide_startstop_t startstop; 816 sector_t block; 817 818 BUG_ON(!blk_rq_started(rq)); 819 820#ifdef DEBUG 821 printk("%s: start_request: current=0x%08lx\n", 822 HWIF(drive)->name, (unsigned long) rq); 823#endif 824 825 /* bail early if we've exceeded max_failures */ 826 if (drive->max_failures && (drive->failures > drive->max_failures)) { 827 rq->cmd_flags |= REQ_FAILED; 828 goto kill_rq; 829 } 830 831 block = rq->sector; 832 if (blk_fs_request(rq) && 833 (drive->media == ide_disk || drive->media == ide_floppy)) { 834 block += drive->sect0; 835 } 836 /* Yecch - this will shift the entire interval, 837 possibly killing some innocent following sector */ 838 if (block == 0 && drive->remap_0_to_1 == 1) 839 block = 1; /* redirect MBR access to EZ-Drive partn table */ 840 841 if (blk_pm_request(rq)) 842 ide_check_pm_state(drive, rq); 843 844 SELECT_DRIVE(drive); 845 if (ide_wait_stat(&startstop, drive, drive->ready_stat, BUSY_STAT|DRQ_STAT, WAIT_READY)) { 846 printk(KERN_ERR "%s: drive not ready for command\n", drive->name); 847 return startstop; 848 } 849 if (!drive->special.all) { 850 ide_driver_t *drv; 851 852 /* 853 * We reset the drive so we need to issue a SETFEATURES. 854 * Do it _after_ do_special() restored device parameters. 855 */ 856 if (drive->current_speed == 0xff) 857 ide_config_drive_speed(drive, drive->desired_speed); 858 859 if (rq->cmd_type == REQ_TYPE_ATA_TASKFILE) 860 return execute_drive_cmd(drive, rq); 861 else if (blk_pm_request(rq)) { 862 struct request_pm_state *pm = rq->data; 863#ifdef DEBUG_PM 864 printk("%s: start_power_step(step: %d)\n", 865 drive->name, rq->pm->pm_step); 866#endif 867 startstop = ide_start_power_step(drive, rq); 868 if (startstop == ide_stopped && 869 pm->pm_step == ide_pm_state_completed) 870 ide_complete_pm_request(drive, rq); 871 return startstop; 872 } 873 874 drv = *(ide_driver_t **)rq->rq_disk->private_data; 875 return drv->do_request(drive, rq, block); 876 } 877 return do_special(drive); 878kill_rq: 879 ide_kill_rq(drive, rq); 880 return ide_stopped; 881} 882 883/** 884 * ide_stall_queue - pause an IDE device 885 * @drive: drive to stall 886 * @timeout: time to stall for (jiffies) 887 * 888 * ide_stall_queue() can be used by a drive to give excess bandwidth back 889 * to the hwgroup by sleeping for timeout jiffies. 890 */ 891 892void ide_stall_queue (ide_drive_t *drive, unsigned long timeout) 893{ 894 if (timeout > WAIT_WORSTCASE) 895 timeout = WAIT_WORSTCASE; 896 drive->sleep = timeout + jiffies; 897 drive->sleeping = 1; 898} 899 900EXPORT_SYMBOL(ide_stall_queue); 901 902#define WAKEUP(drive) ((drive)->service_start + 2 * (drive)->service_time) 903 904/** 905 * choose_drive - select a drive to service 906 * @hwgroup: hardware group to select on 907 * 908 * choose_drive() selects the next drive which will be serviced. 909 * This is necessary because the IDE layer can't issue commands 910 * to both drives on the same cable, unlike SCSI. 911 */ 912 913static inline ide_drive_t *choose_drive (ide_hwgroup_t *hwgroup) 914{ 915 ide_drive_t *drive, *best; 916 917repeat: 918 best = NULL; 919 drive = hwgroup->drive; 920 921 /* 922 * drive is doing pre-flush, ordered write, post-flush sequence. even 923 * though that is 3 requests, it must be seen as a single transaction. 924 * we must not preempt this drive until that is complete 925 */ 926 if (blk_queue_flushing(drive->queue)) { 927 /* 928 * small race where queue could get replugged during 929 * the 3-request flush cycle, just yank the plug since 930 * we want it to finish asap 931 */ 932 blk_remove_plug(drive->queue); 933 return drive; 934 } 935 936 do { 937 if ((!drive->sleeping || time_after_eq(jiffies, drive->sleep)) 938 && !elv_queue_empty(drive->queue)) { 939 if (!best 940 || (drive->sleeping && (!best->sleeping || time_before(drive->sleep, best->sleep))) 941 || (!best->sleeping && time_before(WAKEUP(drive), WAKEUP(best)))) 942 { 943 if (!blk_queue_plugged(drive->queue)) 944 best = drive; 945 } 946 } 947 } while ((drive = drive->next) != hwgroup->drive); 948 if (best && best->nice1 && !best->sleeping && best != hwgroup->drive && best->service_time > WAIT_MIN_SLEEP) { 949 long t = (signed long)(WAKEUP(best) - jiffies); 950 if (t >= WAIT_MIN_SLEEP) { 951 /* 952 * We *may* have some time to spare, but first let's see if 953 * someone can potentially benefit from our nice mood today.. 954 */ 955 drive = best->next; 956 do { 957 if (!drive->sleeping 958 && time_before(jiffies - best->service_time, WAKEUP(drive)) 959 && time_before(WAKEUP(drive), jiffies + t)) 960 { 961 ide_stall_queue(best, min_t(long, t, 10 * WAIT_MIN_SLEEP)); 962 goto repeat; 963 } 964 } while ((drive = drive->next) != best); 965 } 966 } 967 return best; 968} 969 970/* 971 * Issue a new request to a drive from hwgroup 972 * Caller must have already done spin_lock_irqsave(&ide_lock, ..); 973 * 974 * A hwgroup is a serialized group of IDE interfaces. Usually there is 975 * exactly one hwif (interface) per hwgroup, but buggy controllers (eg. CMD640) 976 * may have both interfaces in a single hwgroup to "serialize" access. 977 * Or possibly multiple ISA interfaces can share a common IRQ by being grouped 978 * together into one hwgroup for serialized access. 979 * 980 * Note also that several hwgroups can end up sharing a single IRQ, 981 * possibly along with many other devices. This is especially common in 982 * PCI-based systems with off-board IDE controller cards. 983 * 984 * The IDE driver uses the single global ide_lock spinlock to protect 985 * access to the request queues, and to protect the hwgroup->busy flag. 986 * 987 * The first thread into the driver for a particular hwgroup sets the 988 * hwgroup->busy flag to indicate that this hwgroup is now active, 989 * and then initiates processing of the top request from the request queue. 990 * 991 * Other threads attempting entry notice the busy setting, and will simply 992 * queue their new requests and exit immediately. Note that hwgroup->busy 993 * remains set even when the driver is merely awaiting the next interrupt. 994 * Thus, the meaning is "this hwgroup is busy processing a request". 995 * 996 * When processing of a request completes, the completing thread or IRQ-handler 997 * will start the next request from the queue. If no more work remains, 998 * the driver will clear the hwgroup->busy flag and exit. 999 * 1000 * The ide_lock (spinlock) is used to protect all access to the 1001 * hwgroup->busy flag, but is otherwise not needed for most processing in 1002 * the driver. This makes the driver much more friendlier to shared IRQs 1003 * than previous designs, while remaining 100% (?) SMP safe and capable. 1004 */ 1005static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq) 1006{ 1007 ide_drive_t *drive; 1008 ide_hwif_t *hwif; 1009 struct request *rq; 1010 ide_startstop_t startstop; 1011 int loops = 0; 1012 1013 /* for atari only: POSSIBLY BROKEN HERE(?) */ 1014 ide_get_lock(ide_intr, hwgroup); 1015 1016 /* caller must own ide_lock */ 1017 BUG_ON(!irqs_disabled()); 1018 1019 while (!hwgroup->busy) { 1020 hwgroup->busy = 1; 1021 drive = choose_drive(hwgroup); 1022 if (drive == NULL) { 1023 int sleeping = 0; 1024 unsigned long sleep = 0; /* shut up, gcc */ 1025 hwgroup->rq = NULL; 1026 drive = hwgroup->drive; 1027 do { 1028 if (drive->sleeping && (!sleeping || time_before(drive->sleep, sleep))) { 1029 sleeping = 1; 1030 sleep = drive->sleep; 1031 } 1032 } while ((drive = drive->next) != hwgroup->drive); 1033 if (sleeping) { 1034 /* 1035 * Take a short snooze, and then wake up this hwgroup again. 1036 * This gives other hwgroups on the same a chance to 1037 * play fairly with us, just in case there are big differences 1038 * in relative throughputs.. don't want to hog the cpu too much. 1039 */ 1040 if (time_before(sleep, jiffies + WAIT_MIN_SLEEP)) 1041 sleep = jiffies + WAIT_MIN_SLEEP; 1042#if 1 1043 if (timer_pending(&hwgroup->timer)) 1044 printk(KERN_CRIT "ide_set_handler: timer already active\n"); 1045#endif 1046 /* so that ide_timer_expiry knows what to do */ 1047 hwgroup->sleeping = 1; 1048 hwgroup->req_gen_timer = hwgroup->req_gen; 1049 mod_timer(&hwgroup->timer, sleep); 1050 /* we purposely leave hwgroup->busy==1 1051 * while sleeping */ 1052 } else { 1053 /* Ugly, but how can we sleep for the lock 1054 * otherwise? perhaps from tq_disk? 1055 */ 1056 1057 /* for atari only */ 1058 ide_release_lock(); 1059 hwgroup->busy = 0; 1060 } 1061 1062 /* no more work for this hwgroup (for now) */ 1063 return; 1064 } 1065 again: 1066 hwif = HWIF(drive); 1067 if (hwgroup->hwif->sharing_irq && hwif != hwgroup->hwif) { 1068 /* 1069 * set nIEN for previous hwif, drives in the 1070 * quirk_list may not like intr setups/cleanups 1071 */ 1072 if (drive->quirk_list != 1) 1073 ide_set_irq(drive, 0); 1074 } 1075 hwgroup->hwif = hwif; 1076 hwgroup->drive = drive; 1077 drive->sleeping = 0; 1078 drive->service_start = jiffies; 1079 1080 if (blk_queue_plugged(drive->queue)) { 1081 printk(KERN_ERR "ide: huh? queue was plugged!\n"); 1082 break; 1083 } 1084 1085 /* 1086 * we know that the queue isn't empty, but this can happen 1087 * if the q->prep_rq_fn() decides to kill a request 1088 */ 1089 rq = elv_next_request(drive->queue); 1090 if (!rq) { 1091 hwgroup->busy = 0; 1092 break; 1093 } 1094 1095 /* 1096 * Sanity: don't accept a request that isn't a PM request 1097 * if we are currently power managed. This is very important as 1098 * blk_stop_queue() doesn't prevent the elv_next_request() 1099 * above to return us whatever is in the queue. Since we call 1100 * ide_do_request() ourselves, we end up taking requests while 1101 * the queue is blocked... 1102 * 1103 * We let requests forced at head of queue with ide-preempt 1104 * though. I hope that doesn't happen too much, hopefully not 1105 * unless the subdriver triggers such a thing in its own PM 1106 * state machine. 1107 * 1108 * We count how many times we loop here to make sure we service 1109 * all drives in the hwgroup without looping for ever 1110 */ 1111 if (drive->blocked && !blk_pm_request(rq) && !(rq->cmd_flags & REQ_PREEMPT)) { 1112 drive = drive->next ? drive->next : hwgroup->drive; 1113 if (loops++ < 4 && !blk_queue_plugged(drive->queue)) 1114 goto again; 1115 /* We clear busy, there should be no pending ATA command at this point. */ 1116 hwgroup->busy = 0; 1117 break; 1118 } 1119 1120 hwgroup->rq = rq; 1121 1122 /* 1123 * Some systems have trouble with IDE IRQs arriving while 1124 * the driver is still setting things up. So, here we disable 1125 * the IRQ used by this interface while the request is being started. 1126 * This may look bad at first, but pretty much the same thing 1127 * happens anyway when any interrupt comes in, IDE or otherwise 1128 * -- the kernel masks the IRQ while it is being handled. 1129 */ 1130 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1131 disable_irq_nosync(hwif->irq); 1132 spin_unlock(&ide_lock); 1133 local_irq_enable_in_hardirq(); 1134 /* allow other IRQs while we start this request */ 1135 startstop = start_request(drive, rq); 1136 spin_lock_irq(&ide_lock); 1137 if (masked_irq != IDE_NO_IRQ && hwif->irq != masked_irq) 1138 enable_irq(hwif->irq); 1139 if (startstop == ide_stopped) 1140 hwgroup->busy = 0; 1141 } 1142} 1143 1144/* 1145 * Passes the stuff to ide_do_request 1146 */ 1147void do_ide_request(struct request_queue *q) 1148{ 1149 ide_drive_t *drive = q->queuedata; 1150 1151 ide_do_request(HWGROUP(drive), IDE_NO_IRQ); 1152} 1153 1154/* 1155 * un-busy the hwgroup etc, and clear any pending DMA status. we want to 1156 * retry the current request in pio mode instead of risking tossing it 1157 * all away 1158 */ 1159static ide_startstop_t ide_dma_timeout_retry(ide_drive_t *drive, int error) 1160{ 1161 ide_hwif_t *hwif = HWIF(drive); 1162 struct request *rq; 1163 ide_startstop_t ret = ide_stopped; 1164 1165 /* 1166 * end current dma transaction 1167 */ 1168 1169 if (error < 0) { 1170 printk(KERN_WARNING "%s: DMA timeout error\n", drive->name); 1171 (void)hwif->dma_ops->dma_end(drive); 1172 ret = ide_error(drive, "dma timeout error", 1173 ide_read_status(drive)); 1174 } else { 1175 printk(KERN_WARNING "%s: DMA timeout retry\n", drive->name); 1176 hwif->dma_ops->dma_timeout(drive); 1177 } 1178 1179 /* 1180 * disable dma for now, but remember that we did so because of 1181 * a timeout -- we'll reenable after we finish this next request 1182 * (or rather the first chunk of it) in pio. 1183 */ 1184 drive->retry_pio++; 1185 drive->state = DMA_PIO_RETRY; 1186 ide_dma_off_quietly(drive); 1187 1188 /* 1189 * un-busy drive etc (hwgroup->busy is cleared on return) and 1190 * make sure request is sane 1191 */ 1192 rq = HWGROUP(drive)->rq; 1193 1194 if (!rq) 1195 goto out; 1196 1197 HWGROUP(drive)->rq = NULL; 1198 1199 rq->errors = 0; 1200 1201 if (!rq->bio) 1202 goto out; 1203 1204 rq->sector = rq->bio->bi_sector; 1205 rq->current_nr_sectors = bio_iovec(rq->bio)->bv_len >> 9; 1206 rq->hard_cur_sectors = rq->current_nr_sectors; 1207 rq->buffer = bio_data(rq->bio); 1208out: 1209 return ret; 1210} 1211 1212/** 1213 * ide_timer_expiry - handle lack of an IDE interrupt 1214 * @data: timer callback magic (hwgroup) 1215 * 1216 * An IDE command has timed out before the expected drive return 1217 * occurred. At this point we attempt to clean up the current 1218 * mess. If the current handler includes an expiry handler then 1219 * we invoke the expiry handler, and providing it is happy the 1220 * work is done. If that fails we apply generic recovery rules 1221 * invoking the handler and checking the drive DMA status. We 1222 * have an excessively incestuous relationship with the DMA 1223 * logic that wants cleaning up. 1224 */ 1225 1226void ide_timer_expiry (unsigned long data) 1227{ 1228 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *) data; 1229 ide_handler_t *handler; 1230 ide_expiry_t *expiry; 1231 unsigned long flags; 1232 unsigned long wait = -1; 1233 1234 spin_lock_irqsave(&ide_lock, flags); 1235 1236 if (((handler = hwgroup->handler) == NULL) || 1237 (hwgroup->req_gen != hwgroup->req_gen_timer)) { 1238 /* 1239 * Either a marginal timeout occurred 1240 * (got the interrupt just as timer expired), 1241 * or we were "sleeping" to give other devices a chance. 1242 * Either way, we don't really want to complain about anything. 1243 */ 1244 if (hwgroup->sleeping) { 1245 hwgroup->sleeping = 0; 1246 hwgroup->busy = 0; 1247 } 1248 } else { 1249 ide_drive_t *drive = hwgroup->drive; 1250 if (!drive) { 1251 printk(KERN_ERR "ide_timer_expiry: hwgroup->drive was NULL\n"); 1252 hwgroup->handler = NULL; 1253 } else { 1254 ide_hwif_t *hwif; 1255 ide_startstop_t startstop = ide_stopped; 1256 if (!hwgroup->busy) { 1257 hwgroup->busy = 1; /* paranoia */ 1258 printk(KERN_ERR "%s: ide_timer_expiry: hwgroup->busy was 0 ??\n", drive->name); 1259 } 1260 if ((expiry = hwgroup->expiry) != NULL) { 1261 /* continue */ 1262 if ((wait = expiry(drive)) > 0) { 1263 /* reset timer */ 1264 hwgroup->timer.expires = jiffies + wait; 1265 hwgroup->req_gen_timer = hwgroup->req_gen; 1266 add_timer(&hwgroup->timer); 1267 spin_unlock_irqrestore(&ide_lock, flags); 1268 return; 1269 } 1270 } 1271 hwgroup->handler = NULL; 1272 /* 1273 * We need to simulate a real interrupt when invoking 1274 * the handler() function, which means we need to 1275 * globally mask the specific IRQ: 1276 */ 1277 spin_unlock(&ide_lock); 1278 hwif = HWIF(drive); 1279 /* disable_irq_nosync ?? */ 1280 disable_irq(hwif->irq); 1281 /* local CPU only, 1282 * as if we were handling an interrupt */ 1283 local_irq_disable(); 1284 if (hwgroup->polling) { 1285 startstop = handler(drive); 1286 } else if (drive_is_ready(drive)) { 1287 if (drive->waiting_for_dma) 1288 hwif->dma_ops->dma_lost_irq(drive); 1289 (void)ide_ack_intr(hwif); 1290 printk(KERN_WARNING "%s: lost interrupt\n", drive->name); 1291 startstop = handler(drive); 1292 } else { 1293 if (drive->waiting_for_dma) { 1294 startstop = ide_dma_timeout_retry(drive, wait); 1295 } else 1296 startstop = 1297 ide_error(drive, "irq timeout", 1298 ide_read_status(drive)); 1299 } 1300 drive->service_time = jiffies - drive->service_start; 1301 spin_lock_irq(&ide_lock); 1302 enable_irq(hwif->irq); 1303 if (startstop == ide_stopped) 1304 hwgroup->busy = 0; 1305 } 1306 } 1307 ide_do_request(hwgroup, IDE_NO_IRQ); 1308 spin_unlock_irqrestore(&ide_lock, flags); 1309} 1310 1311/** 1312 * unexpected_intr - handle an unexpected IDE interrupt 1313 * @irq: interrupt line 1314 * @hwgroup: hwgroup being processed 1315 * 1316 * There's nothing really useful we can do with an unexpected interrupt, 1317 * other than reading the status register (to clear it), and logging it. 1318 * There should be no way that an irq can happen before we're ready for it, 1319 * so we needn't worry much about losing an "important" interrupt here. 1320 * 1321 * On laptops (and "green" PCs), an unexpected interrupt occurs whenever 1322 * the drive enters "idle", "standby", or "sleep" mode, so if the status 1323 * looks "good", we just ignore the interrupt completely. 1324 * 1325 * This routine assumes __cli() is in effect when called. 1326 * 1327 * If an unexpected interrupt happens on irq15 while we are handling irq14 1328 * and if the two interfaces are "serialized" (CMD640), then it looks like 1329 * we could screw up by interfering with a new request being set up for 1330 * irq15. 1331 * 1332 * In reality, this is a non-issue. The new command is not sent unless 1333 * the drive is ready to accept one, in which case we know the drive is 1334 * not trying to interrupt us. And ide_set_handler() is always invoked 1335 * before completing the issuance of any new drive command, so we will not 1336 * be accidentally invoked as a result of any valid command completion 1337 * interrupt. 1338 * 1339 * Note that we must walk the entire hwgroup here. We know which hwif 1340 * is doing the current command, but we don't know which hwif burped 1341 * mysteriously. 1342 */ 1343 1344static void unexpected_intr (int irq, ide_hwgroup_t *hwgroup) 1345{ 1346 u8 stat; 1347 ide_hwif_t *hwif = hwgroup->hwif; 1348 1349 /* 1350 * handle the unexpected interrupt 1351 */ 1352 do { 1353 if (hwif->irq == irq) { 1354 stat = hwif->INB(hwif->io_ports.status_addr); 1355 if (!OK_STAT(stat, READY_STAT, BAD_STAT)) { 1356 /* Try to not flood the console with msgs */ 1357 static unsigned long last_msgtime, count; 1358 ++count; 1359 if (time_after(jiffies, last_msgtime + HZ)) { 1360 last_msgtime = jiffies; 1361 printk(KERN_ERR "%s%s: unexpected interrupt, " 1362 "status=0x%02x, count=%ld\n", 1363 hwif->name, 1364 (hwif->next==hwgroup->hwif) ? "" : "(?)", stat, count); 1365 } 1366 } 1367 } 1368 } while ((hwif = hwif->next) != hwgroup->hwif); 1369} 1370 1371/** 1372 * ide_intr - default IDE interrupt handler 1373 * @irq: interrupt number 1374 * @dev_id: hwif group 1375 * @regs: unused weirdness from the kernel irq layer 1376 * 1377 * This is the default IRQ handler for the IDE layer. You should 1378 * not need to override it. If you do be aware it is subtle in 1379 * places 1380 * 1381 * hwgroup->hwif is the interface in the group currently performing 1382 * a command. hwgroup->drive is the drive and hwgroup->handler is 1383 * the IRQ handler to call. As we issue a command the handlers 1384 * step through multiple states, reassigning the handler to the 1385 * next step in the process. Unlike a smart SCSI controller IDE 1386 * expects the main processor to sequence the various transfer 1387 * stages. We also manage a poll timer to catch up with most 1388 * timeout situations. There are still a few where the handlers 1389 * don't ever decide to give up. 1390 * 1391 * The handler eventually returns ide_stopped to indicate the 1392 * request completed. At this point we issue the next request 1393 * on the hwgroup and the process begins again. 1394 */ 1395 1396irqreturn_t ide_intr (int irq, void *dev_id) 1397{ 1398 unsigned long flags; 1399 ide_hwgroup_t *hwgroup = (ide_hwgroup_t *)dev_id; 1400 ide_hwif_t *hwif; 1401 ide_drive_t *drive; 1402 ide_handler_t *handler; 1403 ide_startstop_t startstop; 1404 1405 spin_lock_irqsave(&ide_lock, flags); 1406 hwif = hwgroup->hwif; 1407 1408 if (!ide_ack_intr(hwif)) { 1409 spin_unlock_irqrestore(&ide_lock, flags); 1410 return IRQ_NONE; 1411 } 1412 1413 if ((handler = hwgroup->handler) == NULL || hwgroup->polling) { 1414 /* 1415 * Not expecting an interrupt from this drive. 1416 * That means this could be: 1417 * (1) an interrupt from another PCI device 1418 * sharing the same PCI INT# as us. 1419 * or (2) a drive just entered sleep or standby mode, 1420 * and is interrupting to let us know. 1421 * or (3) a spurious interrupt of unknown origin. 1422 * 1423 * For PCI, we cannot tell the difference, 1424 * so in that case we just ignore it and hope it goes away. 1425 * 1426 * FIXME: unexpected_intr should be hwif-> then we can 1427 * remove all the ifdef PCI crap 1428 */ 1429#ifdef CONFIG_BLK_DEV_IDEPCI 1430 if (hwif->chipset != ide_pci) 1431#endif /* CONFIG_BLK_DEV_IDEPCI */ 1432 { 1433 /* 1434 * Probably not a shared PCI interrupt, 1435 * so we can safely try to do something about it: 1436 */ 1437 unexpected_intr(irq, hwgroup); 1438#ifdef CONFIG_BLK_DEV_IDEPCI 1439 } else { 1440 /* 1441 * Whack the status register, just in case 1442 * we have a leftover pending IRQ. 1443 */ 1444 (void) hwif->INB(hwif->io_ports.status_addr); 1445#endif /* CONFIG_BLK_DEV_IDEPCI */ 1446 } 1447 spin_unlock_irqrestore(&ide_lock, flags); 1448 return IRQ_NONE; 1449 } 1450 drive = hwgroup->drive; 1451 if (!drive) { 1452 /* 1453 * This should NEVER happen, and there isn't much 1454 * we could do about it here. 1455 * 1456 * [Note - this can occur if the drive is hot unplugged] 1457 */ 1458 spin_unlock_irqrestore(&ide_lock, flags); 1459 return IRQ_HANDLED; 1460 } 1461 if (!drive_is_ready(drive)) { 1462 /* 1463 * This happens regularly when we share a PCI IRQ with 1464 * another device. Unfortunately, it can also happen 1465 * with some buggy drives that trigger the IRQ before 1466 * their status register is up to date. Hopefully we have 1467 * enough advance overhead that the latter isn't a problem. 1468 */ 1469 spin_unlock_irqrestore(&ide_lock, flags); 1470 return IRQ_NONE; 1471 } 1472 if (!hwgroup->busy) { 1473 hwgroup->busy = 1; /* paranoia */ 1474 printk(KERN_ERR "%s: ide_intr: hwgroup->busy was 0 ??\n", drive->name); 1475 } 1476 hwgroup->handler = NULL; 1477 hwgroup->req_gen++; 1478 del_timer(&hwgroup->timer); 1479 spin_unlock(&ide_lock); 1480 1481 /* Some controllers might set DMA INTR no matter DMA or PIO; 1482 * bmdma status might need to be cleared even for 1483 * PIO interrupts to prevent spurious/lost irq. 1484 */ 1485 if (hwif->ide_dma_clear_irq && !(drive->waiting_for_dma)) 1486 /* ide_dma_end() needs bmdma status for error checking. 1487 * So, skip clearing bmdma status here and leave it 1488 * to ide_dma_end() if this is dma interrupt. 1489 */ 1490 hwif->ide_dma_clear_irq(drive); 1491 1492 if (drive->unmask) 1493 local_irq_enable_in_hardirq(); 1494 /* service this interrupt, may set handler for next interrupt */ 1495 startstop = handler(drive); 1496 spin_lock_irq(&ide_lock); 1497 1498 /* 1499 * Note that handler() may have set things up for another 1500 * interrupt to occur soon, but it cannot happen until 1501 * we exit from this routine, because it will be the 1502 * same irq as is currently being serviced here, and Linux 1503 * won't allow another of the same (on any CPU) until we return. 1504 */ 1505 drive->service_time = jiffies - drive->service_start; 1506 if (startstop == ide_stopped) { 1507 if (hwgroup->handler == NULL) { /* paranoia */ 1508 hwgroup->busy = 0; 1509 ide_do_request(hwgroup, hwif->irq); 1510 } else { 1511 printk(KERN_ERR "%s: ide_intr: huh? expected NULL handler " 1512 "on exit\n", drive->name); 1513 } 1514 } 1515 spin_unlock_irqrestore(&ide_lock, flags); 1516 return IRQ_HANDLED; 1517} 1518 1519/** 1520 * ide_do_drive_cmd - issue IDE special command 1521 * @drive: device to issue command 1522 * @rq: request to issue 1523 * @action: action for processing 1524 * 1525 * This function issues a special IDE device request 1526 * onto the request queue. 1527 * 1528 * If action is ide_wait, then the rq is queued at the end of the 1529 * request queue, and the function sleeps until it has been processed. 1530 * This is for use when invoked from an ioctl handler. 1531 * 1532 * If action is ide_preempt, then the rq is queued at the head of 1533 * the request queue, displacing the currently-being-processed 1534 * request and this function returns immediately without waiting 1535 * for the new rq to be completed. This is VERY DANGEROUS, and is 1536 * intended for careful use by the ATAPI tape/cdrom driver code. 1537 * 1538 * If action is ide_end, then the rq is queued at the end of the 1539 * request queue, and the function returns immediately without waiting 1540 * for the new rq to be completed. This is again intended for careful 1541 * use by the ATAPI tape/cdrom driver code. 1542 */ 1543 1544int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t action) 1545{ 1546 unsigned long flags; 1547 ide_hwgroup_t *hwgroup = HWGROUP(drive); 1548 int where = ELEVATOR_INSERT_BACK; 1549 1550 rq->errors = 0; 1551 1552 if (action == ide_preempt) 1553 where = ELEVATOR_INSERT_FRONT; 1554 1555 spin_lock_irqsave(&ide_lock, flags); 1556 if (action == ide_preempt) 1557 hwgroup->rq = NULL; 1558 __elv_add_request(drive->queue, rq, where, 1); 1559 __generic_unplug_device(drive->queue); 1560 /* the queue is stopped so it won't be plugged+unplugged */ 1561 if (blk_pm_resume_request(rq)) 1562 do_ide_request(drive->queue); 1563 spin_unlock_irqrestore(&ide_lock, flags); 1564 1565 return 0; 1566} 1567 1568EXPORT_SYMBOL(ide_do_drive_cmd); 1569 1570void ide_pktcmd_tf_load(ide_drive_t *drive, u32 tf_flags, u16 bcount, u8 dma) 1571{ 1572 ide_task_t task; 1573 1574 memset(&task, 0, sizeof(task)); 1575 task.tf_flags = IDE_TFLAG_OUT_LBAH | IDE_TFLAG_OUT_LBAM | 1576 IDE_TFLAG_OUT_FEATURE | tf_flags; 1577 task.tf.feature = dma; /* Use PIO/DMA */ 1578 task.tf.lbam = bcount & 0xff; 1579 task.tf.lbah = (bcount >> 8) & 0xff; 1580 1581 ide_tf_dump(drive->name, &task.tf); 1582 ide_set_irq(drive, 1); 1583 SELECT_MASK(drive, 0); 1584 drive->hwif->tf_load(drive, &task); 1585} 1586 1587EXPORT_SYMBOL_GPL(ide_pktcmd_tf_load); 1588 1589void ide_pad_transfer(ide_drive_t *drive, int write, int len) 1590{ 1591 ide_hwif_t *hwif = drive->hwif; 1592 u8 buf[4] = { 0 }; 1593 1594 while (len > 0) { 1595 if (write) 1596 hwif->output_data(drive, NULL, buf, min(4, len)); 1597 else 1598 hwif->input_data(drive, NULL, buf, min(4, len)); 1599 len -= 4; 1600 } 1601} 1602EXPORT_SYMBOL_GPL(ide_pad_transfer); 1603