SUNRPC expose functions for offline remote xprt functionality

Re-arrange the code that make offline transport and delete transport
callable functions.
Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>

include/linux/sunrpc/xprt.h

@@ -505,4 +505,7 @@ static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
 	return test_and_set_bit(XPRT_BINDING, &xprt->state);
 }
 
+void xprt_set_offline_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps);
+void xprt_set_online_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps);
+void xprt_delete_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps);
 #endif /* _LINUX_SUNRPC_XPRT_H */

net/sunrpc/sysfs.c

@@ -314,33 +314,15 @@ static ssize_t rpc_sysfs_xprt_state_change(struct kobject *kobj,
 		goto release_tasks;
 	}
 	if (offline) {
-		if (!test_and_set_bit(XPRT_OFFLINE, &xprt->state)) {
-			spin_lock(&xps->xps_lock);
-			xps->xps_nactive--;
-			spin_unlock(&xps->xps_lock);
-		}
+		xprt_set_offline_locked(xprt, xps);
 	} else if (online) {
-		if (test_and_clear_bit(XPRT_OFFLINE, &xprt->state)) {
-			spin_lock(&xps->xps_lock);
-			xps->xps_nactive++;
-			spin_unlock(&xps->xps_lock);
-		}
+		xprt_set_online_locked(xprt, xps);
 	} else if (remove) {
-		if (test_bit(XPRT_OFFLINE, &xprt->state)) {
-			if (!test_and_set_bit(XPRT_REMOVE, &xprt->state)) {
-				xprt_force_disconnect(xprt);
-				if (test_bit(XPRT_CONNECTED, &xprt->state)) {
-					if (!xprt->sending.qlen &&
-					    !xprt->pending.qlen &&
-					    !xprt->backlog.qlen &&
-					    !atomic_long_read(&xprt->queuelen))
-						rpc_xprt_switch_remove_xprt(xps, xprt);
-				}
-			}
-		} else {
+		if (test_bit(XPRT_OFFLINE, &xprt->state))
+			xprt_delete_locked(xprt, xps);
+		else
 			count = -EINVAL;
 	}
-	}
 
 release_tasks:
 	xprt_release_write(xprt, NULL);

net/sunrpc/xprt.c

@@ -2152,3 +2152,35 @@ void xprt_put(struct rpc_xprt *xprt)
 		kref_put(&xprt->kref, xprt_destroy_kref);
 }
 EXPORT_SYMBOL_GPL(xprt_put);
+
+void xprt_set_offline_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps)
+{
+	if (!test_and_set_bit(XPRT_OFFLINE, &xprt->state)) {
+		spin_lock(&xps->xps_lock);
+		xps->xps_nactive--;
+		spin_unlock(&xps->xps_lock);
+	}
+}
+
+void xprt_set_online_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps)
+{
+	if (test_and_clear_bit(XPRT_OFFLINE, &xprt->state)) {
+		spin_lock(&xps->xps_lock);
+		xps->xps_nactive++;
+		spin_unlock(&xps->xps_lock);
+	}
+}
+
+void xprt_delete_locked(struct rpc_xprt *xprt, struct rpc_xprt_switch *xps)
+{
+	if (test_and_set_bit(XPRT_REMOVE, &xprt->state))
+		return;
+
+	xprt_force_disconnect(xprt);
+	if (!test_bit(XPRT_CONNECTED, &xprt->state))
+		return;
+
+	if (!xprt->sending.qlen && !xprt->pending.qlen &&
+	    !xprt->backlog.qlen && !atomic_long_read(&xprt->queuelen))
+		rpc_xprt_switch_remove_xprt(xps, xprt);
+}