[PATCH] libata: kill NULL qc handling from ->eng_timeout callbacks

->eng_timeout cannot be invoked with NULL qc anymore.  Add an
assertion in ata_scsi_error() and kill NULL qc handling from all
->eng_timeout callbacks.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

7 files changed, 9 insertions, 48 deletions

diff --git a/drivers/scsi/ahci.c b/drivers/scsi/ahci.c
index c67189a4e0b..fa01894fc41 100644
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -677,19 +677,13 @@ static void ahci_eng_timeout(struct ata_port *ap)
 
 	spin_lock_irqsave(&host_set->lock, flags);
 
+	ahci_restart_port(ap, readl(port_mmio + PORT_IRQ_STAT));
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-	} else {
-		ahci_restart_port(ap, readl(port_mmio + PORT_IRQ_STAT));
-		qc->err_mask |= AC_ERR_TIMEOUT;
-	}
+	qc->err_mask |= AC_ERR_TIMEOUT;
 
 	spin_unlock_irqrestore(&host_set->lock, flags);
 
-	if (qc)
-		ata_eh_qc_complete(qc);
+	ata_eh_qc_complete(qc);
 }
 
 static inline int ahci_host_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index d53e0bce2be..b938c7a3766 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -3524,20 +3524,10 @@ static void ata_qc_timeout(struct ata_queued_cmd *qc)
 
 void ata_eng_timeout(struct ata_port *ap)
 {
-	struct ata_queued_cmd *qc;
-
 	DPRINTK("ENTER\n");
 
-	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (qc)
-		ata_qc_timeout(qc);
-	else {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		goto out;
-	}
+	ata_qc_timeout(ata_qc_from_tag(ap, ap->active_tag));
 
-out:
 	DPRINTK("EXIT\n");
 }
 
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index d67cc2fb569..9d67c676833 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -782,6 +782,7 @@ int ata_scsi_error(struct Scsi_Host *host)
 	spin_lock_irqsave(&ap->host_set->lock, flags);
 	assert(!(ap->flags & ATA_FLAG_IN_EH));
 	ap->flags |= ATA_FLAG_IN_EH;
+	assert(ata_qc_from_tag(ap, ap->active_tag) != NULL);
 	spin_unlock_irqrestore(&ap->host_set->lock, flags);
 
 	ap->ops->eng_timeout(ap);
diff --git a/drivers/scsi/sata_mv.c b/drivers/scsi/sata_mv.c
index 1db05f23f12..6c80527ddd2 100644
--- a/drivers/scsi/sata_mv.c
+++ b/drivers/scsi/sata_mv.c
@@ -2027,13 +2027,8 @@ static void mv_eng_timeout(struct ata_port *ap)
 	mv_err_intr(ap);
 	mv_stop_and_reset(ap);
 
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-	} else {
-		qc->err_mask |= AC_ERR_TIMEOUT;
-		ata_eh_qc_complete(qc);
-	}
+	qc->err_mask |= AC_ERR_TIMEOUT;
+	ata_eh_qc_complete(qc);
 }
 
 /**
diff --git a/drivers/scsi/sata_promise.c b/drivers/scsi/sata_promise.c
index 5d4ed54d945..c9dfd937091 100644
--- a/drivers/scsi/sata_promise.c
+++ b/drivers/scsi/sata_promise.c
@@ -432,11 +432,6 @@ static void pdc_eng_timeout(struct ata_port *ap)
 	spin_lock_irqsave(&host_set->lock, flags);
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		goto out;
-	}
 
 	switch (qc->tf.protocol) {
 	case ATA_PROT_DMA:
@@ -456,10 +451,8 @@ static void pdc_eng_timeout(struct ata_port *ap)
 		break;
 	}
 
-out:
 	spin_unlock_irqrestore(&host_set->lock, flags);
-	if (qc)
-		ata_eh_qc_complete(qc);
+	ata_eh_qc_complete(qc);
 	DPRINTK("EXIT\n");
 }
 
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index f4742ad3c96..962396b36f6 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -639,11 +639,6 @@ static void sil24_eng_timeout(struct ata_port *ap)
 	struct ata_queued_cmd *qc;
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		return;
-	}
 
 	printk(KERN_ERR "ata%u: command timeout\n", ap->id);
 	qc->err_mask |= AC_ERR_TIMEOUT;
diff --git a/drivers/scsi/sata_sx4.c b/drivers/scsi/sata_sx4.c
index 3319f03b61a..212cff4fe5f 100644
--- a/drivers/scsi/sata_sx4.c
+++ b/drivers/scsi/sata_sx4.c
@@ -867,11 +867,6 @@ static void pdc_eng_timeout(struct ata_port *ap)
 	spin_lock_irqsave(&host_set->lock, flags);
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
-		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
-		       ap->id);
-		goto out;
-	}
 
 	switch (qc->tf.protocol) {
 	case ATA_PROT_DMA:
@@ -890,10 +885,8 @@ static void pdc_eng_timeout(struct ata_port *ap)
 		break;
 	}
 
-out:
 	spin_unlock_irqrestore(&host_set->lock, flags);
-	if (qc)
-		ata_eh_qc_complete(qc);
+	ata_eh_qc_complete(qc);
 	DPRINTK("EXIT\n");
 }