ata: libata: remove references to non-existing error_handler()

With commit 65a15d6560df ("scsi: ipr: Remove SATA support") all
libata drivers now have the error_handler() callback provided,
so we can stop checking for non-existing error_handler callback.

Signed-off-by: Hannes Reinecke <hare@suse.de>
[niklas: fixed review comments, rebased, solved conflicts during rebase,
fixed bug that unconditionally dumped all QCs, removed the now unused
function ata_dump_status(), removed the now unreachable failure paths in
atapi_qc_complete(), removed the non-EH function to request ATAPI sense]
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

1 files changed, 63 insertions, 89 deletions

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 0e2acca36c10..159ba6ba19eb 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -571,13 +571,10 @@ void ata_scsi_cmd_error_handler(struct Scsi_Host *host, struct ata_port *ap,
 	/* make sure sff pio task is not running */
 	ata_sff_flush_pio_task(ap);
 
-	if (!ap->ops->error_handler)
-		return;
-
 	/* synchronize with host lock and sort out timeouts */
 
 	/*
-	 * For new EH, all qcs are finished in one of three ways -
+	 * For EH, all qcs are finished in one of three ways -
 	 * normal completion, error completion, and SCSI timeout.
 	 * Both completions can race against SCSI timeout.  When normal
 	 * completion wins, the qc never reaches EH.  When error
@@ -659,94 +656,87 @@ EXPORT_SYMBOL(ata_scsi_cmd_error_handler);
 void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
 {
 	unsigned long flags;
+	struct ata_link *link;
 
-	/* invoke error handler */
-	if (ap->ops->error_handler) {
-		struct ata_link *link;
-
-		/* acquire EH ownership */
-		ata_eh_acquire(ap);
+	/* acquire EH ownership */
+	ata_eh_acquire(ap);
  repeat:
-		/* kill fast drain timer */
-		del_timer_sync(&ap->fastdrain_timer);
+	/* kill fast drain timer */
+	del_timer_sync(&ap->fastdrain_timer);
 
-		/* process port resume request */
-		ata_eh_handle_port_resume(ap);
+	/* process port resume request */
+	ata_eh_handle_port_resume(ap);
 
-		/* fetch & clear EH info */
-		spin_lock_irqsave(ap->lock, flags);
+	/* fetch & clear EH info */
+	spin_lock_irqsave(ap->lock, flags);
 
-		ata_for_each_link(link, ap, HOST_FIRST) {
-			struct ata_eh_context *ehc = &link->eh_context;
-			struct ata_device *dev;
+	ata_for_each_link(link, ap, HOST_FIRST) {
+		struct ata_eh_context *ehc = &link->eh_context;
+		struct ata_device *dev;
 
-			memset(&link->eh_context, 0, sizeof(link->eh_context));
-			link->eh_context.i = link->eh_info;
-			memset(&link->eh_info, 0, sizeof(link->eh_info));
+		memset(&link->eh_context, 0, sizeof(link->eh_context));
+		link->eh_context.i = link->eh_info;
+		memset(&link->eh_info, 0, sizeof(link->eh_info));
 
-			ata_for_each_dev(dev, link, ENABLED) {
-				int devno = dev->devno;
+		ata_for_each_dev(dev, link, ENABLED) {
+			int devno = dev->devno;
 
-				ehc->saved_xfer_mode[devno] = dev->xfer_mode;
-				if (ata_ncq_enabled(dev))
-					ehc->saved_ncq_enabled |= 1 << devno;
-			}
+			ehc->saved_xfer_mode[devno] = dev->xfer_mode;
+			if (ata_ncq_enabled(dev))
+				ehc->saved_ncq_enabled |= 1 << devno;
 		}
+	}
 
-		ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
-		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
-		ap->excl_link = NULL;	/* don't maintain exclusion over EH */
+	ap->pflags |= ATA_PFLAG_EH_IN_PROGRESS;
+	ap->pflags &= ~ATA_PFLAG_EH_PENDING;
+	ap->excl_link = NULL;	/* don't maintain exclusion over EH */
 
-		spin_unlock_irqrestore(ap->lock, flags);
+	spin_unlock_irqrestore(ap->lock, flags);
 
-		/* invoke EH, skip if unloading or suspended */
-		if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
-			ap->ops->error_handler(ap);
-		else {
-			/* if unloading, commence suicide */
-			if ((ap->pflags & ATA_PFLAG_UNLOADING) &&
-			    !(ap->pflags & ATA_PFLAG_UNLOADED))
-				ata_eh_unload(ap);
-			ata_eh_finish(ap);
-		}
+	/* invoke EH, skip if unloading or suspended */
+	if (!(ap->pflags & (ATA_PFLAG_UNLOADING | ATA_PFLAG_SUSPENDED)))
+		ap->ops->error_handler(ap);
+	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);
+	/* process port suspend request */
+	ata_eh_handle_port_suspend(ap);
 
-		/* Exception might have happened after ->error_handler
-		 * recovered the port but before this point.  Repeat
-		 * EH in such case.
-		 */
-		spin_lock_irqsave(ap->lock, flags);
+	/*
+	 * Exception might have happened after ->error_handler recovered the
+	 * port but before this point.  Repeat EH in such case.
+	 */
+	spin_lock_irqsave(ap->lock, flags);
 
-		if (ap->pflags & ATA_PFLAG_EH_PENDING) {
-			if (--ap->eh_tries) {
-				spin_unlock_irqrestore(ap->lock, flags);
-				goto repeat;
-			}
-			ata_port_err(ap,
-				     "EH pending after %d tries, giving up\n",
-				     ATA_EH_MAX_TRIES);
-			ap->pflags &= ~ATA_PFLAG_EH_PENDING;
+	if (ap->pflags & ATA_PFLAG_EH_PENDING) {
+		if (--ap->eh_tries) {
+			spin_unlock_irqrestore(ap->lock, flags);
+			goto repeat;
 		}
+		ata_port_err(ap,
+			     "EH pending after %d tries, giving up\n",
+			     ATA_EH_MAX_TRIES);
+		ap->pflags &= ~ATA_PFLAG_EH_PENDING;
+	}
 
-		/* this run is complete, make sure EH info is clear */
-		ata_for_each_link(link, ap, HOST_FIRST)
-			memset(&link->eh_info, 0, sizeof(link->eh_info));
+	/* this run is complete, make sure EH info is clear */
+	ata_for_each_link(link, ap, HOST_FIRST)
+		memset(&link->eh_info, 0, sizeof(link->eh_info));
 
-		/* end eh (clear host_eh_scheduled) while holding
-		 * ap->lock such that if exception occurs after this
-		 * point but before EH completion, SCSI midlayer will
-		 * re-initiate EH.
-		 */
-		ap->ops->end_eh(ap);
+	/*
+	 * end eh (clear host_eh_scheduled) while holding ap->lock such that if
+	 * exception occurs after this point but before EH completion, SCSI
+	 * midlayer will re-initiate EH.
+	 */
+	ap->ops->end_eh(ap);
 
-		spin_unlock_irqrestore(ap->lock, flags);
-		ata_eh_release(ap);
-	} else {
-		WARN_ON(ata_qc_from_tag(ap, ap->link.active_tag) == NULL);
-		ap->ops->eng_timeout(ap);
-	}
+	spin_unlock_irqrestore(ap->lock, flags);
+	ata_eh_release(ap);
 
 	scsi_eh_flush_done_q(&ap->eh_done_q);
 
@@ -912,8 +902,6 @@ void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
 {
 	struct ata_port *ap = qc->ap;
 
-	WARN_ON(!ap->ops->error_handler);
-
 	qc->flags |= ATA_QCFLAG_EH;
 	ata_eh_set_pending(ap, 1);
 
@@ -934,8 +922,6 @@ void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
  */
 void ata_std_sched_eh(struct ata_port *ap)
 {
-	WARN_ON(!ap->ops->error_handler);
-
 	if (ap->pflags & ATA_PFLAG_INITIALIZING)
 		return;
 
@@ -989,8 +975,6 @@ static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)
 	struct ata_queued_cmd *qc;
 	int tag, nr_aborted = 0;
 
-	WARN_ON(!ap->ops->error_handler);
-
 	/* we're gonna abort all commands, no need for fast drain */
 	ata_eh_set_pending(ap, 0);
 
@@ -1065,8 +1049,6 @@ EXPORT_SYMBOL_GPL(ata_port_abort);
  */
 static void __ata_port_freeze(struct ata_port *ap)
 {
-	WARN_ON(!ap->ops->error_handler);
-
 	if (ap->ops->freeze)
 		ap->ops->freeze(ap);
 
@@ -1091,8 +1073,6 @@ static void __ata_port_freeze(struct ata_port *ap)
  */
 int ata_port_freeze(struct ata_port *ap)
 {
-	WARN_ON(!ap->ops->error_handler);
-
 	__ata_port_freeze(ap);
 
 	return ata_port_abort(ap);
@@ -1112,9 +1092,6 @@ void ata_eh_freeze_port(struct ata_port *ap)
 {
 	unsigned long flags;
 
-	if (!ap->ops->error_handler)
-		return;
-
 	spin_lock_irqsave(ap->lock, flags);
 	__ata_port_freeze(ap);
 	spin_unlock_irqrestore(ap->lock, flags);
@@ -1134,9 +1111,6 @@ void ata_eh_thaw_port(struct ata_port *ap)
 {
 	unsigned long flags;
 
-	if (!ap->ops->error_handler)
-		return;
-
 	spin_lock_irqsave(ap->lock, flags);
 
 	ap->pflags &= ~ATA_PFLAG_FROZEN;