1 files changed, 107 insertions, 25 deletions

diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index 66f23b376fa0..34dd7b26ee5f 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -184,7 +184,6 @@ static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
 				   struct super_block *sb)
 {
 	struct dentry *dentry;
-	int err = 0;
 
 	switch (event) {
 	case RPC_PIPEFS_MOUNT:
@@ -201,7 +200,7 @@ static int __rpc_clnt_handle_event(struct rpc_clnt *clnt, unsigned long event,
 		printk(KERN_ERR "%s: unknown event: %ld\n", __func__, event);
 		return -ENOTSUPP;
 	}
-	return err;
+	return 0;
 }
 
 static int __rpc_pipefs_event(struct rpc_clnt *clnt, unsigned long event,
@@ -988,7 +987,6 @@ void rpc_task_set_client(struct rpc_task *task, struct rpc_clnt *clnt)
 {
 
 	if (clnt != NULL) {
-		rpc_task_release_client(task);
 		if (task->tk_xprt == NULL)
 			task->tk_xprt = xprt_iter_get_next(&clnt->cl_xpi);
 		task->tk_client = clnt;
@@ -1693,6 +1691,7 @@ call_allocate(struct rpc_task *task)
 	struct rpc_rqst *req = task->tk_rqstp;
 	struct rpc_xprt *xprt = req->rq_xprt;
 	struct rpc_procinfo *proc = task->tk_msg.rpc_proc;
+	int status;
 
 	dprint_status(task);
 
@@ -1718,11 +1717,14 @@ call_allocate(struct rpc_task *task)
 	req->rq_rcvsize = RPC_REPHDRSIZE + slack + proc->p_replen;
 	req->rq_rcvsize <<= 2;
 
-	req->rq_buffer = xprt->ops->buf_alloc(task,
-					req->rq_callsize + req->rq_rcvsize);
-	if (req->rq_buffer != NULL)
-		return;
+	status = xprt->ops->buf_alloc(task);
 	xprt_inject_disconnect(xprt);
+	if (status == 0)
+		return;
+	if (status != -ENOMEM) {
+		rpc_exit(task, status);
+		return;
+	}
 
 	dprintk("RPC: %5u rpc_buffer allocation failed\n", task->tk_pid);
 
@@ -1748,18 +1750,6 @@ rpc_task_force_reencode(struct rpc_task *task)
 	task->tk_rqstp->rq_bytes_sent = 0;
 }
 
-static inline void
-rpc_xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
-{
-	buf->head[0].iov_base = start;
-	buf->head[0].iov_len = len;
-	buf->tail[0].iov_len = 0;
-	buf->page_len = 0;
-	buf->flags = 0;
-	buf->len = 0;
-	buf->buflen = len;
-}
-
 /*
  * 3.	Encode arguments of an RPC call
  */
@@ -1772,12 +1762,12 @@ rpc_xdr_encode(struct rpc_task *task)
 
 	dprint_status(task);
 
-	rpc_xdr_buf_init(&req->rq_snd_buf,
-			 req->rq_buffer,
-			 req->rq_callsize);
-	rpc_xdr_buf_init(&req->rq_rcv_buf,
-			 (char *)req->rq_buffer + req->rq_callsize,
-			 req->rq_rcvsize);
+	xdr_buf_init(&req->rq_snd_buf,
+		     req->rq_buffer,
+		     req->rq_callsize);
+	xdr_buf_init(&req->rq_rcv_buf,
+		     req->rq_rbuffer,
+		     req->rq_rcvsize);
 
 	p = rpc_encode_header(task);
 	if (p == NULL) {
@@ -2616,6 +2606,70 @@ int rpc_clnt_test_and_add_xprt(struct rpc_clnt *clnt,
 EXPORT_SYMBOL_GPL(rpc_clnt_test_and_add_xprt);
 
 /**
+ * rpc_clnt_setup_test_and_add_xprt()
+ *
+ * This is an rpc_clnt_add_xprt setup() function which returns 1 so:
+ *   1) caller of the test function must dereference the rpc_xprt_switch
+ *   and the rpc_xprt.
+ *   2) test function must call rpc_xprt_switch_add_xprt, usually in
+ *   the rpc_call_done routine.
+ *
+ * Upon success (return of 1), the test function adds the new
+ * transport to the rpc_clnt xprt switch
+ *
+ * @clnt: struct rpc_clnt to get the new transport
+ * @xps:  the rpc_xprt_switch to hold the new transport
+ * @xprt: the rpc_xprt to test
+ * @data: a struct rpc_add_xprt_test pointer that holds the test function
+ *        and test function call data
+ */
+int rpc_clnt_setup_test_and_add_xprt(struct rpc_clnt *clnt,
+				     struct rpc_xprt_switch *xps,
+				     struct rpc_xprt *xprt,
+				     void *data)
+{
+	struct rpc_cred *cred;
+	struct rpc_task *task;
+	struct rpc_add_xprt_test *xtest = (struct rpc_add_xprt_test *)data;
+	int status = -EADDRINUSE;
+
+	xprt = xprt_get(xprt);
+	xprt_switch_get(xps);
+
+	if (rpc_xprt_switch_has_addr(xps, (struct sockaddr *)&xprt->addr))
+		goto out_err;
+
+	/* Test the connection */
+	cred = authnull_ops.lookup_cred(NULL, NULL, 0);
+	task = rpc_call_null_helper(clnt, xprt, cred,
+				    RPC_TASK_SOFT | RPC_TASK_SOFTCONN,
+				    NULL, NULL);
+	put_rpccred(cred);
+	if (IS_ERR(task)) {
+		status = PTR_ERR(task);
+		goto out_err;
+	}
+	status = task->tk_status;
+	rpc_put_task(task);
+
+	if (status < 0)
+		goto out_err;
+
+	/* rpc_xprt_switch and rpc_xprt are deferrenced by add_xprt_test() */
+	xtest->add_xprt_test(clnt, xprt, xtest->data);
+
+	/* so that rpc_clnt_add_xprt does not call rpc_xprt_switch_add_xprt */
+	return 1;
+out_err:
+	xprt_put(xprt);
+	xprt_switch_put(xps);
+	pr_info("RPC:   rpc_clnt_test_xprt failed: %d addr %s not added\n",
+		status, xprt->address_strings[RPC_DISPLAY_ADDR]);
+	return status;
+}
+EXPORT_SYMBOL_GPL(rpc_clnt_setup_test_and_add_xprt);
+
+/**
  * rpc_clnt_add_xprt - Add a new transport to a rpc_clnt
  * @clnt: pointer to struct rpc_clnt
  * @xprtargs: pointer to struct xprt_create
@@ -2697,6 +2751,34 @@ rpc_cap_max_reconnect_timeout(struct rpc_clnt *clnt, unsigned long timeo)
 }
 EXPORT_SYMBOL_GPL(rpc_cap_max_reconnect_timeout);
 
+void rpc_clnt_xprt_switch_put(struct rpc_clnt *clnt)
+{
+	xprt_switch_put(rcu_dereference(clnt->cl_xpi.xpi_xpswitch));
+}
+EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_put);
+
+void rpc_clnt_xprt_switch_add_xprt(struct rpc_clnt *clnt, struct rpc_xprt *xprt)
+{
+	rpc_xprt_switch_add_xprt(rcu_dereference(clnt->cl_xpi.xpi_xpswitch),
+				 xprt);
+}
+EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_add_xprt);
+
+bool rpc_clnt_xprt_switch_has_addr(struct rpc_clnt *clnt,
+				   const struct sockaddr *sap)
+{
+	struct rpc_xprt_switch *xps;
+	bool ret;
+
+	xps = rcu_dereference(clnt->cl_xpi.xpi_xpswitch);
+
+	rcu_read_lock();
+	ret = rpc_xprt_switch_has_addr(xps, sap);
+	rcu_read_unlock();
+	return ret;
+}
+EXPORT_SYMBOL_GPL(rpc_clnt_xprt_switch_has_addr);
+
 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 static void rpc_show_header(void)
 {