SUNRPC: Make NFS swap work with multipath (15001e5a) · Commits · e / devices / android_kernel_fairphone_FP5

net/sunrpc/clnt.c

+24 −42

Original line number	Diff line number	Diff line
		@@ -2554,57 +2554,39 @@ void rpc_show_tasks(struct net *net)
		#endif

		#if IS_ENABLED(CONFIG_SUNRPC_SWAP)
		static int
		rpc_clnt_swap_activate_callback(struct rpc_clnt *clnt,
		struct rpc_xprt *xprt,
		void *dummy)
		{
		return xprt_enable_swap(xprt);
		}

		int
		rpc_clnt_swap_activate(struct rpc_clnt *clnt)
		{
		int ret = 0;
		struct rpc_xprt *xprt;

		if (atomic_inc_return(&clnt->cl_swapper) == 1) {
		retry:
		rcu_read_lock();
		xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
		rcu_read_unlock();
		if (!xprt) {
		/*
		* If we didn't get a reference, then we likely are
		* racing with a migration event. Wait for a grace
		* period and try again.
		*/
		synchronize_rcu();
		goto retry;
		if (atomic_inc_return(&clnt->cl_swapper) == 1)
		return rpc_clnt_iterate_for_each_xprt(clnt,
		rpc_clnt_swap_activate_callback, NULL);
		return 0;
		}
		EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);

		ret = xprt_enable_swap(xprt);
		xprt_put(xprt);
		}
		return ret;
		static int
		rpc_clnt_swap_deactivate_callback(struct rpc_clnt *clnt,
		struct rpc_xprt *xprt,
		void *dummy)
		{
		xprt_disable_swap(xprt);
		return 0;
		}
		EXPORT_SYMBOL_GPL(rpc_clnt_swap_activate);

		void
		rpc_clnt_swap_deactivate(struct rpc_clnt *clnt)
		{
		struct rpc_xprt *xprt;

		if (atomic_dec_if_positive(&clnt->cl_swapper) == 0) {
		retry:
		rcu_read_lock();
		xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
		rcu_read_unlock();
		if (!xprt) {
		/*
		* If we didn't get a reference, then we likely are
		* racing with a migration event. Wait for a grace
		* period and try again.
		*/
		synchronize_rcu();
		goto retry;
		}

		xprt_disable_swap(xprt);
		xprt_put(xprt);
		}
		if (atomic_dec_if_positive(&clnt->cl_swapper) == 0)
		rpc_clnt_iterate_for_each_xprt(clnt,
		rpc_clnt_swap_deactivate_callback, NULL);
		}
		EXPORT_SYMBOL_GPL(rpc_clnt_swap_deactivate);
		#endif /* CONFIG_SUNRPC_SWAP */