Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit ece180d1 authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik
Browse files

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: default avatarTejun Heo <tj@kernel.org>
Signed-off-by: default avatarJeff Garzik <jgarzik@redhat.com>
parent ad74e4c1

drivers/ata/libata-core.c

+4 −19
Original line number Diff line number Diff line
@@ -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);

	}



	/* 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);

	/* it better be dead now */

	WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED));



	ata_port_wait_eh(ap);

	cancel_rearming_delayed_work(&ap->hotplug_task);



 skip_eh:

drivers/ata/libata-eh.c

+31 −1
Original line number Diff line number Diff line
@@ -491,6 +491,31 @@ enum blk_eh_timer_return ata_scsi_timed_out(struct scsi_cmnd *cmd) 
	return ret;

}



static void ata_eh_unload(struct ata_port *ap)

{

	struct ata_link *link;

	struct ata_device *dev;

	unsigned long flags;



	/* Restore SControl IPM and SPD for the next driver and

	 * disable attached 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);

	}



	/* freeze and set UNLOADED */

	spin_lock_irqsave(ap->lock, flags);



	ata_port_freeze(ap);			/* won't be thawed */

	ap->pflags &= ~ATA_PFLAG_EH_PENDING;	/* clear pending from freeze */

	ap->pflags |= ATA_PFLAG_UNLOADED;



	spin_unlock_irqrestore(ap->lock, flags);

}



/**

 *	ata_scsi_error - SCSI layer error handler callback

 *	@host: SCSI host on which error occurred
@@ -618,8 +643,13 @@ void ata_scsi_error(struct Scsi_Host *host) 
		/* invoke EH, skip if unloading or suspended */

		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))

			ap->ops->error_handler(ap);

		else

		else {

			/* if unloading, commence suicide */

			if ((ap->pflags & ATA_PFLAG_UNLOADING) &&

			    !(ap->pflags & ATA_PFLAG_UNLOADED))

				ata_eh_unload(ap);

			ata_eh_finish(ap);

		}



		/* process port suspend request */

		ata_eh_handle_port_suspend(ap);

include/linux/libata.h

+2 −1
Original line number Diff line number Diff line
@@ -213,10 +213,11 @@ enum { 
	ATA_PFLAG_FROZEN	= (1 << 2), /* port is frozen */

	ATA_PFLAG_RECOVERED	= (1 << 3), /* recovery action performed */

	ATA_PFLAG_LOADING	= (1 << 4), /* boot/loading probe */

	ATA_PFLAG_UNLOADING	= (1 << 5), /* module is unloading */

	ATA_PFLAG_SCSI_HOTPLUG	= (1 << 6), /* SCSI hotplug scheduled */

	ATA_PFLAG_INITIALIZING	= (1 << 7), /* being initialized, don't touch */

	ATA_PFLAG_RESETTING	= (1 << 8), /* reset in progress */

	ATA_PFLAG_UNLOADING	= (1 << 9), /* driver is being unloaded */

	ATA_PFLAG_UNLOADED	= (1 << 10), /* driver is unloaded */



	ATA_PFLAG_SUSPENDED	= (1 << 17), /* port is suspended (power) */

	ATA_PFLAG_PM_PENDING	= (1 << 18), /* PM operation pending */