[SCSI] scsi_transport_sas: add destructor for bsg

There's currently no destructor for the bsg components. If you insert
and remove the module, you see the bsg devices building up and up. This
patch adds the destructor in the correct place in the transport class so
that the bsg and request queue are removed just before the device
destruction.

Acked-by: FUJITA Tomonori <[e-mail]>
Signed-off-by: James Bottomley <[e-mail]>

drivers/scsi/scsi_transport_sas.c

···
 struct sas_host_attrs {
 	struct list_head rphy_list;
 	struct mutex lock;
+	struct request_queue *q;
 	u32 next_target_id;
 	u32 next_expander_id;
 	int next_port_id;
···
 	}
 
 	if (rphy)
+		rphy->q = q;
+	else
+		to_sas_host_attrs(shost)->q = q;
+
+	if (rphy)
 		q->queuedata = rphy;
 	else
 		q->queuedata = shost;
···
 	set_bit(QUEUE_FLAG_BIDI, &q->queue_flags);
 
 	return 0;
+}
+
+static void sas_bsg_remove(struct Scsi_Host *shost, struct sas_rphy *rphy)
+{
+	struct request_queue *q;
+
+	if (rphy)
+		q = rphy->q;
+	else
+		q = to_sas_host_attrs(shost)->q;
+
+	if (!q)
+		return;
+
+	bsg_unregister_queue(q);
+	blk_cleanup_queue(q);
 }
 
 /*
···
 	return 0;
 }
 
+static int sas_host_remove(struct transport_container *tc, struct device *dev,
+			   struct class_device *cdev)
+{
+	struct Scsi_Host *shost = dev_to_shost(dev);
+
+	sas_bsg_remove(shost, NULL);
+
+	return 0;
+}
+
 static DECLARE_TRANSPORT_CLASS(sas_host_class,
-		"sas_host", sas_host_setup, NULL, NULL);
+		"sas_host", sas_host_setup, sas_host_remove, NULL);
 
 static int sas_host_match(struct attribute_container *cont,
 			    struct device *dev)
···
 	mutex_lock(&sas_host->lock);
 	list_del(&rphy->list);
 	mutex_unlock(&sas_host->lock);
+
+	sas_bsg_remove(shost, rphy);
 
 	transport_destroy_device(dev);
 

include/scsi/scsi_transport_sas.h

···
 #define phy_to_shost(phy) \
 	dev_to_shost((phy)->dev.parent)
 
+struct request_queue;
 struct sas_rphy {
 	struct device		dev;
 	struct sas_identify	identify;
 	struct list_head	list;
+	struct request_queue	*q;
 	u32			scsi_target_id;
 };