libata: fix NCQ devices behind port multipliers
For devices behind sata port multipliers, we have to make sure that
they share a tag map since all tags for that PMP must be unique.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c
index 4b95c43..bbb30d8 100644
--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -1107,6 +1107,15 @@
depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id));
depth = min(ATA_MAX_QUEUE - 1, depth);
+
+ /*
+ * If this device is behind a port multiplier, we have
+ * to share the tag map between all devices on that PMP.
+ * Set up the shared tag map here and we get automatic.
+ */
+ if (dev->link->ap->pmp_link)
+ scsi_init_shared_tag_map(sdev->host, ATA_MAX_QUEUE - 1);
+
scsi_set_tag_type(sdev, MSG_SIMPLE_TAG);
scsi_activate_tcq(sdev, depth);
}