From 7ffcdaa670164a2ad3844a5ef6df5423782ba290 Mon Sep 17 00:00:00 2001
From: Olga Kornievskaia <olga.kornievskaia@gmail.com>
Date: Mon, 25 Jul 2022 09:32:21 -0400
Subject: [PATCH] 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 |  3 +++
 net/sunrpc/sysfs.c          | 28 +++++-----------------------
 net/sunrpc/xprt.c           | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 40 insertions(+), 23 deletions(-)

diff --git a/include/linux/sunrpc/xprt.h b/include/linux/sunrpc/xprt.h
index 522bbf937957..0d51b9f9ea37 100644
--- a/include/linux/sunrpc/xprt.h
+++ b/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 */
diff --git a/net/sunrpc/sysfs.c b/net/sunrpc/sysfs.c
index a3a2f8aeb80e..7330eb9a70cf 100644
--- a/net/sunrpc/sysfs.c
+++ b/net/sunrpc/sysfs.c
@@ -314,32 +314,14 @@ 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:
diff --git a/net/sunrpc/xprt.c b/net/sunrpc/xprt.c
index 86d62cffba0d..8f8e3c952f24 100644
--- a/net/sunrpc/xprt.c
+++ b/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);
+}