diff options
| -rw-r--r-- | drivers/ide/ide-io.c | 54 |
1 files changed, 32 insertions, 22 deletions
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c index d5f3c77beadd..db96138fefcd 100644 --- a/drivers/ide/ide-io.c +++ b/drivers/ide/ide-io.c @@ -466,14 +466,10 @@ void do_ide_request(struct request_queue *q) if (!ide_lock_port(hwif)) { ide_hwif_t *prev_port; + + WARN_ON_ONCE(hwif->rq); repeat: prev_port = hwif->host->cur_port; - - if (drive->dev_flags & IDE_DFLAG_BLOCKED) - rq = hwif->rq; - else - WARN_ON_ONCE(hwif->rq); - if (drive->dev_flags & IDE_DFLAG_SLEEPING && time_after(drive->sleep, jiffies)) { ide_unlock_port(hwif); @@ -500,29 +496,43 @@ repeat: hwif->cur_dev = drive; drive->dev_flags &= ~(IDE_DFLAG_SLEEPING | IDE_DFLAG_PARKED); - if (rq == NULL) { - spin_unlock_irq(&hwif->lock); - spin_lock_irq(q->queue_lock); - /* - * we know that the queue isn't empty, but this can - * happen if ->prep_rq_fn() decides to kill a request - */ + spin_unlock_irq(&hwif->lock); + spin_lock_irq(q->queue_lock); + /* + * we know that the queue isn't empty, but this can happen + * if the q->prep_rq_fn() decides to kill a request + */ + if (!rq) rq = blk_fetch_request(drive->queue); - spin_unlock_irq(q->queue_lock); - spin_lock_irq(&hwif->lock); - if (rq == NULL) { - ide_unlock_port(hwif); - goto out; - } + spin_unlock_irq(q->queue_lock); + spin_lock_irq(&hwif->lock); + + if (!rq) { + ide_unlock_port(hwif); + goto out; } /* * Sanity: don't accept a request that isn't a PM request - * if we are currently power managed. + * if we are currently power managed. This is very important as + * blk_stop_queue() doesn't prevent the blk_fetch_request() + * above to return us whatever is in the queue. Since we call + * ide_do_request() ourselves, we end up taking requests while + * the queue is blocked... + * + * We let requests forced at head of queue with ide-preempt + * though. I hope that doesn't happen too much, hopefully not + * unless the subdriver triggers such a thing in its own PM + * state machine. */ - BUG_ON((drive->dev_flags & IDE_DFLAG_BLOCKED) && - blk_pm_request(rq) == 0); + if ((drive->dev_flags & IDE_DFLAG_BLOCKED) && + blk_pm_request(rq) == 0 && + (rq->cmd_flags & REQ_PREEMPT) == 0) { + /* there should be no pending command at this point */ + ide_unlock_port(hwif); + goto plug_device; + } hwif->rq = rq; |