3 files changed, 34 insertions, 24 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index ba5f11cebee2..74f4c662f776 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1418,31 +1418,27 @@ static int ahci_init_msi(struct pci_dev *pdev, unsigned int n_ports,
 	 * Message mode could be enforced. In this case assume that advantage
 	 * of multipe MSIs is negated and use single MSI mode instead.
 	 */
-	nvec = pci_alloc_irq_vectors(pdev, n_ports, INT_MAX,
-			PCI_IRQ_MSIX | PCI_IRQ_MSI);
-	if (nvec > 0) {
-		if (!(readl(hpriv->mmio + HOST_CTL) & HOST_MRSM)) {
-			hpriv->get_irq_vector = ahci_get_irq_vector;
-			hpriv->flags |= AHCI_HFLAG_MULTI_MSI;
-			return nvec;
-		}
+	if (n_ports > 1) {
+		nvec = pci_alloc_irq_vectors(pdev, n_ports, INT_MAX,
+				PCI_IRQ_MSIX | PCI_IRQ_MSI);
+		if (nvec > 0) {
+			if (!(readl(hpriv->mmio + HOST_CTL) & HOST_MRSM)) {
+				hpriv->get_irq_vector = ahci_get_irq_vector;
+				hpriv->flags |= AHCI_HFLAG_MULTI_MSI;
+				return nvec;
+			}
 
-		/*
-		 * Fallback to single MSI mode if the controller enforced MRSM
-		 * mode.
-		 */
-		printk(KERN_INFO "ahci: MRSM is on, fallback to single MSI\n");
-		pci_free_irq_vectors(pdev);
+			/*
+			 * Fallback to single MSI mode if the controller
+			 * enforced MRSM mode.
+			 */
+			printk(KERN_INFO
+				"ahci: MRSM is on, fallback to single MSI\n");
+			pci_free_irq_vectors(pdev);
+		}
 	}
 
 	/*
-	 * -ENOSPC indicated we don't have enough vectors.  Don't bother trying
-	 * a single vectors for any other error:
-	 */
-	if (nvec < 0 && nvec != -ENOSPC)
-		return nvec;
-
-	/*
 	 * If the host is not capable of supporting per-port vectors, fall
 	 * back to single MSI before finally attempting single MSI-X.
 	 */
@@ -1617,7 +1613,7 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		/* legacy intx interrupts */
 		pci_intx(pdev, 1);
 	}
-	hpriv->irq = pdev->irq;
+	hpriv->irq = pci_irq_vector(pdev, 0);
 
 	if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
 		host->flags |= ATA_HOST_PARALLEL_SCAN;
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 9cceb4a875a5..8e575fbdf31d 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -1088,7 +1088,7 @@ static void ata_gen_passthru_sense(struct ata_queued_cmd *qc)
 		desc[1] = tf->command; /* status */
 		desc[2] = tf->device;
 		desc[3] = tf->nsect;
-		desc[0] = 0;
+		desc[7] = 0;
 		if (tf->flags & ATA_TFLAG_LBA48)  {
 			desc[8] |= 0x80;
 			if (tf->hob_nsect)
@@ -1159,6 +1159,7 @@ static void ata_scsi_sdev_config(struct scsi_device *sdev)
 {
 	sdev->use_10_for_rw = 1;
 	sdev->use_10_for_ms = 1;
+	sdev->no_write_same = 1;
 
 	/* Schedule policy is determined by ->qc_defer() callback and
 	 * it needs to see every deferred qc.  Set dev_blocked to 1 to
diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index efc48bf89d51..823e938c9a78 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -4090,7 +4090,20 @@ static int mv_platform_probe(struct platform_device *pdev)
 
 	/* allocate host */
 	if (pdev->dev.of_node) {
-		of_property_read_u32(pdev->dev.of_node, "nr-ports", &n_ports);
+		rc = of_property_read_u32(pdev->dev.of_node, "nr-ports",
+					   &n_ports);
+		if (rc) {
+			dev_err(&pdev->dev,
+				"error parsing nr-ports property: %d\n", rc);
+			return rc;
+		}
+
+		if (n_ports <= 0) {
+			dev_err(&pdev->dev, "nr-ports must be positive: %d\n",
+				n_ports);
+			return -EINVAL;
+		}
+
 		irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
 	} else {
 		mv_platform_data = dev_get_platdata(&pdev->dev);