[PATCH] libata-ncq: implement NCQ device configuration
Now that all NCQ related stuff are in place, implement NCQ device
configuration and bump ATA_MAX_QUEUE to 32 thus activating NCQ
support.
Original implementation is from Jens Axboe.
Signed-off-by: Tejun Heo <htejun@gmail.com>
diff --git a/drivers/scsi/libata-scsi.c b/drivers/scsi/libata-scsi.c
index 9bef68c..996058a 100644
--- a/drivers/scsi/libata-scsi.c
+++ b/drivers/scsi/libata-scsi.c
@@ -41,6 +41,7 @@
#include <scsi/scsi_eh.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_request.h>
+#include <scsi/scsi_tcq.h>
#include <scsi/scsi_transport.h>
#include <linux/libata.h>
#include <linux/hdreg.h>
@@ -684,6 +685,14 @@
request_queue_t *q = sdev->request_queue;
blk_queue_max_hw_segments(q, q->max_hw_segments - 1);
}
+
+ if (dev->flags & ATA_DFLAG_NCQ) {
+ int depth;
+
+ depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
+ depth = min(ATA_MAX_QUEUE - 1, depth);
+ scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, depth);
+ }
}
/**
@@ -718,6 +727,43 @@
}
/**
+ * 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);
+ struct ata_device *dev;
+ int max_depth;
+
+ if (queue_depth < 1)
+ return sdev->queue_depth;
+
+ dev = ata_scsi_find_dev(ap, sdev);
+ if (!dev || !ata_dev_enabled(dev))
+ return sdev->queue_depth;
+
+ max_depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
+ max_depth = min(ATA_MAX_QUEUE - 1, max_depth);
+ if (queue_depth > max_depth)
+ queue_depth = max_depth;
+
+ scsi_adjust_queue_depth(sdev, MSG_SIMPLE_TAG, queue_depth);
+ return queue_depth;
+}
+
+/**
* ata_scsi_start_stop_xlat - Translate SCSI START STOP UNIT command
* @qc: Storage for translated ATA taskfile
* @scsicmd: SCSI command to translate