ata: start separating SATA specific code from libata-scsi.c

Start separating SATA specific code from libata-scsi.c:

* un-static ata_scsi_find_dev()

* move following code to libata-sata.c:
  - SATA only sysfs device attributes handling
  - __ata_change_queue_depth()
  - ata_scsi_change_queue_depth()

* cover with CONFIG_SATA_HOST ifdef SATA only sysfs device
  attributes handling code and ATA_SHT_NCQ() macro in
  <linux/libata.h>

Code size savings on m68k arch using (modified) atari_defconfig:

   text    data     bss     dec     hex filename
before:
  20702     105     576   21383    5387 drivers/ata/libata-scsi.o
after:
  19137      23     576   19736    4d18 drivers/ata/libata-scsi.o

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 298 insertions, 0 deletions

diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index f3ad4aca5d09..341699f5af20 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -8,6 +8,7 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <scsi/scsi_device.h>
 #include <linux/libata.h>
 
 #include "libata.h"
@@ -764,3 +765,300 @@ bool sata_lpm_ignore_phy_events(struct ata_link *link)
 	return false;
 }
 EXPORT_SYMBOL_GPL(sata_lpm_ignore_phy_events);
+
+static const char *ata_lpm_policy_names[] = {
+	[ATA_LPM_UNKNOWN]		= "max_performance",
+	[ATA_LPM_MAX_POWER]		= "max_performance",
+	[ATA_LPM_MED_POWER]		= "medium_power",
+	[ATA_LPM_MED_POWER_WITH_DIPM]	= "med_power_with_dipm",
+	[ATA_LPM_MIN_POWER_WITH_PARTIAL] = "min_power_with_partial",
+	[ATA_LPM_MIN_POWER]		= "min_power",
+};
+
+static ssize_t ata_scsi_lpm_store(struct device *device,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(device);
+	struct ata_port *ap = ata_shost_to_port(shost);
+	struct ata_link *link;
+	struct ata_device *dev;
+	enum ata_lpm_policy policy;
+	unsigned long flags;
+
+	/* UNKNOWN is internal state, iterate from MAX_POWER */
+	for (policy = ATA_LPM_MAX_POWER;
+	     policy < ARRAY_SIZE(ata_lpm_policy_names); policy++) {
+		const char *name = ata_lpm_policy_names[policy];
+
+		if (strncmp(name, buf, strlen(name)) == 0)
+			break;
+	}
+	if (policy == ARRAY_SIZE(ata_lpm_policy_names))
+		return -EINVAL;
+
+	spin_lock_irqsave(ap->lock, flags);
+
+	ata_for_each_link(link, ap, EDGE) {
+		ata_for_each_dev(dev, &ap->link, ENABLED) {
+			if (dev->horkage & ATA_HORKAGE_NOLPM) {
+				count = -EOPNOTSUPP;
+				goto out_unlock;
+			}
+		}
+	}
+
+	ap->target_lpm_policy = policy;
+	ata_port_schedule_eh(ap);
+out_unlock:
+	spin_unlock_irqrestore(ap->lock, flags);
+	return count;
+}
+
+static ssize_t ata_scsi_lpm_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct ata_port *ap = ata_shost_to_port(shost);
+
+	if (ap->target_lpm_policy >= ARRAY_SIZE(ata_lpm_policy_names))
+		return -EINVAL;
+
+	return snprintf(buf, PAGE_SIZE, "%s\n",
+			ata_lpm_policy_names[ap->target_lpm_policy]);
+}
+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_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;
+	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);
+	dev = ata_scsi_find_dev(ap, sdev);
+	if (unlikely(!dev))
+		return  -ENODEV;
+
+	spin_lock_irq(ap->lock);
+	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);
+	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;
+}
+
+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);
+
+struct device_attribute *ata_ncq_sdev_attrs[] = {
+	&dev_attr_unload_heads,
+	&dev_attr_ncq_prio_enable,
+	NULL
+};
+EXPORT_SYMBOL_GPL(ata_ncq_sdev_attrs);
+
+static ssize_t
+ata_scsi_em_message_store(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct ata_port *ap = ata_shost_to_port(shost);
+	if (ap->ops->em_store && (ap->flags & ATA_FLAG_EM))
+		return ap->ops->em_store(ap, buf, count);
+	return -EINVAL;
+}
+
+static ssize_t
+ata_scsi_em_message_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct ata_port *ap = ata_shost_to_port(shost);
+
+	if (ap->ops->em_show && (ap->flags & ATA_FLAG_EM))
+		return ap->ops->em_show(ap, buf);
+	return -EINVAL;
+}
+DEVICE_ATTR(em_message, S_IRUGO | S_IWUSR,
+		ata_scsi_em_message_show, ata_scsi_em_message_store);
+EXPORT_SYMBOL_GPL(dev_attr_em_message);
+
+static ssize_t
+ata_scsi_em_message_type_show(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct ata_port *ap = ata_shost_to_port(shost);
+
+	return snprintf(buf, 23, "%d\n", ap->em_message_type);
+}
+DEVICE_ATTR(em_message_type, S_IRUGO,
+		  ata_scsi_em_message_type_show, NULL);
+EXPORT_SYMBOL_GPL(dev_attr_em_message_type);
+
+static ssize_t
+ata_scsi_activity_show(struct device *dev, struct device_attribute *attr,
+		char *buf)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ata_port *ap = ata_shost_to_port(sdev->host);
+	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
+
+	if (atadev && ap->ops->sw_activity_show &&
+	    (ap->flags & ATA_FLAG_SW_ACTIVITY))
+		return ap->ops->sw_activity_show(atadev, buf);
+	return -EINVAL;
+}
+
+static ssize_t
+ata_scsi_activity_store(struct device *dev, struct device_attribute *attr,
+	const char *buf, size_t count)
+{
+	struct scsi_device *sdev = to_scsi_device(dev);
+	struct ata_port *ap = ata_shost_to_port(sdev->host);
+	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
+	enum sw_activity val;
+	int rc;
+
+	if (atadev && ap->ops->sw_activity_store &&
+	    (ap->flags & ATA_FLAG_SW_ACTIVITY)) {
+		val = simple_strtoul(buf, NULL, 0);
+		switch (val) {
+		case OFF: case BLINK_ON: case BLINK_OFF:
+			rc = ap->ops->sw_activity_store(atadev, val);
+			if (!rc)
+				return count;
+			else
+				return rc;
+		}
+	}
+	return -EINVAL;
+}
+DEVICE_ATTR(sw_activity, S_IWUSR | S_IRUGO, ata_scsi_activity_show,
+			ata_scsi_activity_store);
+EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
+
+/**
+ *	__ata_change_queue_depth - helper for ata_scsi_change_queue_depth
+ *	@ap: ATA port to which the device change the queue depth
+ *	@sdev: SCSI device to configure queue depth for
+ *	@queue_depth: new queue depth
+ *
+ *	libsas and libata have different approaches for associating a sdev to
+ *	its ata_port.
+ *
+ */
+int __ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev,
+			     int queue_depth)
+{
+	struct ata_device *dev;
+	unsigned long flags;
+
+	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
+		return sdev->queue_depth;
+
+	dev = ata_scsi_find_dev(ap, sdev);
+	if (!dev || !ata_dev_enabled(dev))
+		return sdev->queue_depth;
+
+	/* NCQ enabled? */
+	spin_lock_irqsave(ap->lock, flags);
+	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
+	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
+		dev->flags |= ATA_DFLAG_NCQ_OFF;
+		queue_depth = 1;
+	}
+	spin_unlock_irqrestore(ap->lock, flags);
+
+	/* limit and apply queue depth */
+	queue_depth = min(queue_depth, sdev->host->can_queue);
+	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
+	queue_depth = min(queue_depth, ATA_MAX_QUEUE);
+
+	if (sdev->queue_depth == queue_depth)
+		return -EINVAL;
+
+	return scsi_change_queue_depth(sdev, queue_depth);
+}
+EXPORT_SYMBOL_GPL(__ata_change_queue_depth);
+
+/**
+ *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
+ *	@sdev: SCSI device to configure queue depth for
+ *	@queue_depth: new queue depth
+ *
+ *	This is libata standard hostt->change_queue_depth callback.
+ *	SCSI will call into this callback when user tries to set queue
+ *	depth via sysfs.
+ *
+ *	LOCKING:
+ *	SCSI layer (we don't care)
+ *
+ *	RETURNS:
+ *	Newly configured queue depth.
+ */
+int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
+{
+	struct ata_port *ap = ata_shost_to_port(sdev->host);
+
+	return __ata_change_queue_depth(ap, sdev, queue_depth);
+}
+EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);