ata: ATA Command Priority Disabled By Default
Add a sysfs entry to turn on priority information being passed
to a ATA device. By default this feature is turned off.
This patch depends on ata: Enabling ATA Command Priorities
tj: Renamed ncq_prio_on to ncq_prio_enable and removed trivial
ata_ncq_prio_on() and open-coded the test.
Signed-off-by: Adam Manzanares <adam.manzanares@hgst.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 2bccc3c..87597a3 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -271,6 +271,73 @@ DEVICE_ATTR(unload_heads, S_IRUGO | S_IWUSR,
ata_scsi_park_show, ata_scsi_park_store);
EXPORT_SYMBOL_GPL(dev_attr_unload_heads);
+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_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) {
+ rc = -ENODEV;
+ goto unlock;
+ }
+
+ ncq_prio_enable = dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLE;
+
+unlock:
+ spin_unlock_irq(ap->lock);
+
+ return rc ? rc : snprintf(buf, 20, "%u\n", ncq_prio_enable);
+}
+
+static ssize_t ata_ncq_prio_enable_store(struct device *device,
+ struct device_attribute *attr,
+ const char *buf, size_t len)
+{
+ struct scsi_device *sdev = to_scsi_device(device);
+ struct ata_port *ap;
+ struct ata_device *dev;
+ long int input;
+ unsigned long flags;
+ int rc;
+
+ rc = kstrtol(buf, 10, &input);
+ if (rc)
+ return rc;
+ if ((input < 0) || (input > 1))
+ return -EINVAL;
+
+ ap = ata_shost_to_port(sdev->host);
+
+ spin_lock_irqsave(ap->lock, flags);
+ dev = ata_scsi_find_dev(ap, sdev);
+ if (unlikely(!dev)) {
+ rc = -ENODEV;
+ goto unlock;
+ }
+
+ if (input)
+ dev->flags |= ATA_DFLAG_NCQ_PRIO_ENABLE;
+ else
+ dev->flags &= ~ATA_DFLAG_NCQ_PRIO_ENABLE;
+
+unlock:
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ return rc ? rc : len;
+}
+
+DEVICE_ATTR(ncq_prio_enable, S_IRUGO | S_IWUSR,
+ ata_ncq_prio_enable_show, ata_ncq_prio_enable_store);
+EXPORT_SYMBOL_GPL(dev_attr_ncq_prio_enable);
+
void ata_scsi_set_sense(struct ata_device *dev, struct scsi_cmnd *cmd,
u8 sk, u8 asc, u8 ascq)
{
@@ -402,6 +469,7 @@ EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
struct device_attribute *ata_common_sdev_attrs[] = {
&dev_attr_unload_heads,
+ &dev_attr_ncq_prio_enable,
NULL
};
EXPORT_SYMBOL_GPL(ata_common_sdev_attrs);