On 02/03/2024 20:16, Igor Pylypiv wrote:
Export libata NCQ Priority configuration helpers to be reused
for libsas managed SATA devices.
Signed-off-by: Igor Pylypiv <ipylypiv@xxxxxxxxxx>
This looks ok. Some small code comments below, though.
---
drivers/ata/libata-sata.c | 139 +++++++++++++++++++++++++++-----------
include/linux/libata.h | 4 ++
2 files changed, 103 insertions(+), 40 deletions(-)
diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index 0fb1934875f2..a8d5e36d5211 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -848,29 +848,73 @@ 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);
+/**
+ * ata_ncq_prio_supported - Check if device supports NCQ Priority
+ * @ap: ATA port of the target device
+ * @sdev: SCSI device
+ *
+ * Helper to check if device supports NCQ Priority feature,
+ * usable with both libsas and libata.
+ */
+int ata_ncq_prio_supported(struct ata_port *ap, struct scsi_device *sdev)
+{
+ struct ata_device *dev;
+ unsigned long flags;
+ int rc;
+
+ spin_lock_irqsave(ap->lock, flags);
+ dev = ata_scsi_find_dev(ap, sdev);
+ if (!dev)
+ rc = -ENODEV;
+ else
+ rc = !!(dev->flags & ATA_DFLAG_NCQ_PRIO);
+ spin_unlock_irqrestore(ap->lock, flags);
+ return rc;
+}
I'm not the biggest fan of functions which effectively return both a
boolean and an error code.
I like this patten more:
int ata_ncq_prio_supported(struct ata_port *ap, struct scsi_device
*sdev, bool *supported)
{
...
if (rc)
return rc;
*supported = true/false.
return 0;
}
No big deal, though.
+EXPORT_SYMBOL_GPL(ata_ncq_prio_supported);
+
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);
+ int rc;
+
+ rc = ata_ncq_prio_supported(ap, sdev);
+ if (rc < 0)
+ return rc;
+
+ return sysfs_emit(buf, "%d\n", rc);
+}
+
+DEVICE_ATTR(ncq_prio_supported, S_IRUGO, ata_ncq_prio_supported_show, NULL);
+EXPORT_SYMBOL_GPL(dev_attr_ncq_prio_supported);
+
+/**
+ * ata_ncq_prio_enabled - Check if NCQ Priority is enabled
+ * @ap: ATA port of the target device
+ * @sdev: SCSI device
+ *
+ * Helper to check if NCQ Priority feature is enabled,
+ * usable with both libsas and libata.
It's usable by anything which uses libata, really. For the moment that
is libsas and libata.
+ */
+int ata_ncq_prio_enabled(struct ata_port *ap, struct scsi_device *sdev)
+{
struct ata_device *dev;
- bool ncq_prio_supported;
- int rc = 0;
+ unsigned long flags;
+ int rc;
- spin_lock_irq(ap->lock);
+ spin_lock_irqsave(ap->lock, flags);
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);
+ rc = !!(dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLED);
+ spin_unlock_irqrestore(ap->lock, flags);
+ return rc;
}
-
-DEVICE_ATTR(ncq_prio_supported, S_IRUGO, ata_ncq_prio_supported_show, NULL);
-EXPORT_SYMBOL_GPL(dev_attr_ncq_prio_supported);
+EXPORT_SYMBOL_GPL(ata_ncq_prio_enabled);
static ssize_t ata_ncq_prio_enable_show(struct device *device,
struct device_attribute *attr,
@@ -878,50 +922,45 @@ static ssize_t ata_ncq_prio_enable_show(struct device *device,
{
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_enable;
- int rc = 0;
+ int rc;
- spin_lock_irq(ap->lock);
- dev = ata_scsi_find_dev(ap, sdev);
- if (!dev)
- rc = -ENODEV;
- else
- ncq_prio_enable = dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLED;
- spin_unlock_irq(ap->lock);
+ rc = ata_ncq_prio_enabled(ap, sdev);
+ if (rc < 0)
+ return rc;
- return rc ? rc : sysfs_emit(buf, "%u\n", ncq_prio_enable);
+ return sysfs_emit(buf, "%d\n", rc);
}
-static ssize_t ata_ncq_prio_enable_store(struct device *device,
- struct device_attribute *attr,
- const char *buf, size_t len)
+/**
+ * ata_ncq_prio_enable - Enable/disable NCQ Priority
+ * @ap: ATA port of the target device
+ * @sdev: SCSI device
+ * @enable: true - enable NCQ Priority, false - disable NCQ Priority
+ *
+ * Helper to enable/disable NCQ Priority feature, usable with both
+ * libsas and libata.
+ */
+int ata_ncq_prio_enable(struct ata_port *ap, struct scsi_device *sdev,
+ bool enable)
{
- struct scsi_device *sdev = to_scsi_device(device);
- struct ata_port *ap;
struct ata_device *dev;
- long int input;
+ unsigned long flags;
int rc = 0;
- rc = kstrtol(buf, 10, &input);
- if (rc)
- return rc;
- if ((input < 0) || (input > 1))
- return -EINVAL;
+ spin_lock_irqsave(ap->lock, flags);
- ap = ata_shost_to_port(sdev->host);
dev = ata_scsi_find_dev(ap, sdev);
- if (unlikely(!dev))
- return -ENODEV;
-
- spin_lock_irq(ap->lock);
+ if (unlikely(!dev)) {
no need for unlikely() - this is not fathpath
+ rc = -ENODEV;
+ goto unlock;
+ }
if (!(dev->flags & ATA_DFLAG_NCQ_PRIO)) {
rc = -EINVAL;
goto unlock;
