ata: libata-scsi: Fix initialization of device queue depth

For SATA devices supporting NCQ, drivers using libsas first initialize a
scsi device queue depth based on the controller and device capabilities,
leading to the scsi device queue_depth field being 32 (ATA maximum queue
depth) for most setup. However, if libata was loaded using the
force=[ID]]noncq argument, the default queue depth should be set to 1 to
reflect the fact that queuable commands will never be used. This is
consistent with manually setting a device queue depth to 1 through sysfs
as that disables NCQ use for the device.

Fix ata_scsi_dev_config() to honor the noncq parameter by sertting the
device queue depth to 1 for devices that do not have the ATA_DFLAG_NCQ
flag set.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: John Garry <john.garry@huawei.com>

diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 29e2f55c6faa79b9ac1bacbd5bc4cb8c4bdf2b07..ff9602a0e54efbc93fe215c281a54acd54203503 100644 (file)
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -1055,6 +1055,7 @@ EXPORT_SYMBOL_GPL(ata_scsi_dma_need_drain);
 int ata_scsi_dev_config(struct scsi_device *sdev, struct ata_device *dev)
 {
        struct request_queue *q = sdev->request_queue;
+       int depth = 1;
 
        if (!ata_id_has_unload(dev->id))
                dev->flags |= ATA_DFLAG_NO_UNLOAD;
@@ -1100,13 +1101,10 @@ int ata_scsi_dev_config(struct scsi_device *sdev, struct ata_device *dev)
        if (dev->flags & ATA_DFLAG_AN)
                set_bit(SDEV_EVT_MEDIA_CHANGE, sdev->supported_events);
 
-       if (dev->flags & ATA_DFLAG_NCQ) {
-               int depth;
-
+       if (dev->flags & ATA_DFLAG_NCQ)
                depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
-               depth = min(ATA_MAX_QUEUE, depth);
-               scsi_change_queue_depth(sdev, depth);
-       }
+       depth = min(ATA_MAX_QUEUE, depth);
+       scsi_change_queue_depth(sdev, depth);
 
        if (dev->flags & ATA_DFLAG_TRUSTED)
                sdev->security_supported = 1;