1 files changed, 37 insertions, 25 deletions

diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index 8adeab76dd38..8f3ff830ab0c 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -834,28 +834,46 @@ DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
 	    ata_scsi_lpm_show, ata_scsi_lpm_store);
 EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
 
+static ssize_t ata_ncq_prio_supported_show(struct device *device,
+					   struct device_attribute *attr,
+					   char *buf)
+{
+	struct scsi_device *sdev = to_scsi_device(device);
+	struct ata_port *ap = ata_shost_to_port(sdev->host);
+	struct ata_device *dev;
+	bool ncq_prio_supported;
+	int rc = 0;
+
+	spin_lock_irq(ap->lock);
+	dev = ata_scsi_find_dev(ap, sdev);
+	if (!dev)
+		rc = -ENODEV;
+	else
+		ncq_prio_supported = dev->flags & ATA_DFLAG_NCQ_PRIO;
+	spin_unlock_irq(ap->lock);
+
+	return rc ? rc : sysfs_emit(buf, "%u\n", ncq_prio_supported);
+}
+
+DEVICE_ATTR(ncq_prio_supported, S_IRUGO, ata_ncq_prio_supported_show, NULL);
+EXPORT_SYMBOL_GPL(dev_attr_ncq_prio_supported);
+
 static ssize_t ata_ncq_prio_enable_show(struct device *device,
 					struct device_attribute *attr,
 					char *buf)
 {
 	struct scsi_device *sdev = to_scsi_device(device);
-	struct ata_port *ap;
+	struct ata_port *ap = ata_shost_to_port(sdev->host);
 	struct ata_device *dev;
 	bool ncq_prio_enable;
 	int rc = 0;
 
-	ap = ata_shost_to_port(sdev->host);
-
 	spin_lock_irq(ap->lock);
 	dev = ata_scsi_find_dev(ap, sdev);
-	if (!dev) {
+	if (!dev)
 		rc = -ENODEV;
-		goto unlock;
-	}
-
-	ncq_prio_enable = dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLE;
-
-unlock:
+	else
+		ncq_prio_enable = dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLE;
 	spin_unlock_irq(ap->lock);
 
 	return rc ? rc : snprintf(buf, 20, "%u\n", ncq_prio_enable);
@@ -869,7 +887,7 @@ static ssize_t ata_ncq_prio_enable_store(struct device *device,
 	struct ata_port *ap;
 	struct ata_device *dev;
 	long int input;
-	int rc;
+	int rc = 0;
 
 	rc = kstrtol(buf, 10, &input);
 	if (rc)
@@ -883,27 +901,20 @@ static ssize_t ata_ncq_prio_enable_store(struct device *device,
 		return  -ENODEV;
 
 	spin_lock_irq(ap->lock);
+
+	if (!(dev->flags & ATA_DFLAG_NCQ_PRIO)) {
+		rc = -EINVAL;
+		goto unlock;
+	}
+
 	if (input)
 		dev->flags |= ATA_DFLAG_NCQ_PRIO_ENABLE;
 	else
 		dev->flags &= ~ATA_DFLAG_NCQ_PRIO_ENABLE;
 
-	dev->link->eh_info.action |= ATA_EH_REVALIDATE;
-	dev->link->eh_info.flags |= ATA_EHI_QUIET;
-	ata_port_schedule_eh(ap);
+unlock:
 	spin_unlock_irq(ap->lock);
 
-	ata_port_wait_eh(ap);
-
-	if (input) {
-		spin_lock_irq(ap->lock);
-		if (!(dev->flags & ATA_DFLAG_NCQ_PRIO)) {
-			dev->flags &= ~ATA_DFLAG_NCQ_PRIO_ENABLE;
-			rc = -EIO;
-		}
-		spin_unlock_irq(ap->lock);
-	}
-
 	return rc ? rc : len;
 }
 
@@ -914,6 +925,7 @@ EXPORT_SYMBOL_GPL(dev_attr_ncq_prio_enable);
 struct device_attribute *ata_ncq_sdev_attrs[] = {
 	&dev_attr_unload_heads,
 	&dev_attr_ncq_prio_enable,
+	&dev_attr_ncq_prio_supported,
 	NULL
 };
 EXPORT_SYMBOL_GPL(ata_ncq_sdev_attrs);