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>
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 1ecc3cb..837fb60 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -6107,8 +6107,6 @@
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 @@
/* 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: