libata: perform port detach in EH

ata_port_detach() first made sure EH saw ATA_PFLAG_UNLOADING and then
assumed EH context belongs to it and performed detach operation
itself.  However, UNLOADING doesn't disable all of EH and this could
lead to problems including triggering WARN_ON()'s in EH path.

This patch makes port detach behave more like other EH actions such
that ata_port_detach() requests EH to detach and waits for completion.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
This commit is contained in:
Tejun Heo
2008-11-03 20:04:37 +09:00
committed by Jeff Garzik
parent ad74e4c18d
commit ece180d1cf
3 changed files with 37 additions and 21 deletions

View File

@ -6107,8 +6107,6 @@ int ata_host_activate(struct ata_host *host, int irq,
static void ata_port_detach(struct ata_port *ap)
{
unsigned long flags;
struct ata_link *link;
struct ata_device *dev;
if (!ap->ops->error_handler)
goto skip_eh;
@ -6116,28 +6114,15 @@ static void ata_port_detach(struct ata_port *ap)
/* tell EH we're leaving & flush EH */
spin_lock_irqsave(ap->lock, flags);
ap->pflags |= ATA_PFLAG_UNLOADING;
ata_port_schedule_eh(ap);
spin_unlock_irqrestore(ap->lock, flags);
/* wait till EH commits suicide */
ata_port_wait_eh(ap);
/* EH is now guaranteed to see UNLOADING - EH context belongs
* to us. Restore SControl and disable all existing devices.
*/
ata_for_each_link(link, ap, PMP_FIRST) {
sata_scr_write(link, SCR_CONTROL, link->saved_scontrol & 0xff0);
ata_for_each_dev(dev, link, ALL)
ata_dev_disable(dev);
}
/* it better be dead now */
WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED));
/* Final freeze & EH. All in-flight commands are aborted. EH
* will be skipped and retrials will be terminated with bad
* target.
*/
spin_lock_irqsave(ap->lock, flags);
ata_port_freeze(ap); /* won't be thawed */
spin_unlock_irqrestore(ap->lock, flags);
ata_port_wait_eh(ap);
cancel_rearming_delayed_work(&ap->hotplug_task);
skip_eh: