Commit 3503e0acbfab0dbcd24ccadd5fe841f3f8290e81
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e18ed145c7
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Revert "ide: improve handling of Power Management requests"
This reverts commit a1317f714af7aed60ddc182d0122477cbe36ee9b.
Showing 1 changed file with 32 additions and 22 deletions Side-by-side Diff
drivers/ide/ide-io.c
| ... | ... | @@ -466,14 +466,10 @@ |
| 466 | 466 | |
| 467 | 467 | if (!ide_lock_port(hwif)) { |
| 468 | 468 | ide_hwif_t *prev_port; |
| 469 | + | |
| 470 | + WARN_ON_ONCE(hwif->rq); | |
| 469 | 471 | repeat: |
| 470 | 472 | prev_port = hwif->host->cur_port; |
| 471 | - | |
| 472 | - if (drive->dev_flags & IDE_DFLAG_BLOCKED) | |
| 473 | - rq = hwif->rq; | |
| 474 | - else | |
| 475 | - WARN_ON_ONCE(hwif->rq); | |
| 476 | - | |
| 477 | 473 | if (drive->dev_flags & IDE_DFLAG_SLEEPING && |
| 478 | 474 | time_after(drive->sleep, jiffies)) { |
| 479 | 475 | ide_unlock_port(hwif); |
| 480 | 476 | |
| 481 | 477 | |
| 482 | 478 | |
| 483 | 479 | |
| ... | ... | @@ -500,29 +496,43 @@ |
| 500 | 496 | hwif->cur_dev = drive; |
| 501 | 497 | drive->dev_flags &= ~(IDE_DFLAG_SLEEPING | IDE_DFLAG_PARKED); |
| 502 | 498 | |
| 503 | - if (rq == NULL) { | |
| 504 | - spin_unlock_irq(&hwif->lock); | |
| 505 | - spin_lock_irq(q->queue_lock); | |
| 506 | - /* | |
| 507 | - * we know that the queue isn't empty, but this can | |
| 508 | - * happen if ->prep_rq_fn() decides to kill a request | |
| 509 | - */ | |
| 499 | + spin_unlock_irq(&hwif->lock); | |
| 500 | + spin_lock_irq(q->queue_lock); | |
| 501 | + /* | |
| 502 | + * we know that the queue isn't empty, but this can happen | |
| 503 | + * if the q->prep_rq_fn() decides to kill a request | |
| 504 | + */ | |
| 505 | + if (!rq) | |
| 510 | 506 | rq = blk_fetch_request(drive->queue); |
| 511 | - spin_unlock_irq(q->queue_lock); | |
| 512 | - spin_lock_irq(&hwif->lock); | |
| 513 | 507 | |
| 514 | - if (rq == NULL) { | |
| 515 | - ide_unlock_port(hwif); | |
| 516 | - goto out; | |
| 517 | - } | |
| 508 | + spin_unlock_irq(q->queue_lock); | |
| 509 | + spin_lock_irq(&hwif->lock); | |
| 510 | + | |
| 511 | + if (!rq) { | |
| 512 | + ide_unlock_port(hwif); | |
| 513 | + goto out; | |
| 518 | 514 | } |
| 519 | 515 | |
| 520 | 516 | /* |
| 521 | 517 | * Sanity: don't accept a request that isn't a PM request |
| 522 | - * if we are currently power managed. | |
| 518 | + * if we are currently power managed. This is very important as | |
| 519 | + * blk_stop_queue() doesn't prevent the blk_fetch_request() | |
| 520 | + * above to return us whatever is in the queue. Since we call | |
| 521 | + * ide_do_request() ourselves, we end up taking requests while | |
| 522 | + * the queue is blocked... | |
| 523 | + * | |
| 524 | + * We let requests forced at head of queue with ide-preempt | |
| 525 | + * though. I hope that doesn't happen too much, hopefully not | |
| 526 | + * unless the subdriver triggers such a thing in its own PM | |
| 527 | + * state machine. | |
| 523 | 528 | */ |
| 524 | - BUG_ON((drive->dev_flags & IDE_DFLAG_BLOCKED) && | |
| 525 | - blk_pm_request(rq) == 0); | |
| 529 | + if ((drive->dev_flags & IDE_DFLAG_BLOCKED) && | |
| 530 | + blk_pm_request(rq) == 0 && | |
| 531 | + (rq->cmd_flags & REQ_PREEMPT) == 0) { | |
| 532 | + /* there should be no pending command at this point */ | |
| 533 | + ide_unlock_port(hwif); | |
| 534 | + goto plug_device; | |
| 535 | + } | |
| 526 | 536 | |
| 527 | 537 | hwif->rq = rq; |
| 528 | 538 |