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authorDavid S. Miller <davem@davemloft.net>2009-07-06 12:39:27 -0700
committerDavid S. Miller <davem@davemloft.net>2009-07-06 12:39:27 -0700
commit3503e0acbfab0dbcd24ccadd5fe841f3f8290e81 (patch)
tree3a9b186c73e731fdbe74fa08ae743cbf4b061b5f
parente18ed145c7f556f1de8350c32739bf35b26df705 (diff)
Revert "ide: improve handling of Power Management requests"
This reverts commit a1317f714af7aed60ddc182d0122477cbe36ee9b.
-rw-r--r--drivers/ide/ide-io.c54
1 files changed, 32 insertions, 22 deletions
diff --git a/drivers/ide/ide-io.c b/drivers/ide/ide-io.c
index d5f3c77bead..db96138fefc 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;