[PATCH] RPC: proper soft timeout behavior for rpcbind
Implement a best practice: for soft mounts, an rpcbind timeout should
cause an RPC request to fail.
This also provides an FSM hook for retrying an rpcbind with a different
rpcbind protocol version. We'll use this later to try multiple rpcbind
protocol versions when binding. To enable this, expose the RPC error
code returned during a portmap request to the FSM so it can make some
decision about how to report, retry, or fail the request.
Test-plan:
Hundreds of passes with connectathon NFSv3 locking suite, on the client
and server.
Version: Thu, 11 Aug 2005 16:01:53 -0400
Signed-off-by: Chuck Lever <cel@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/net/sunrpc/clnt.c b/net/sunrpc/clnt.c
index f17e615..2d3cf0a 100644
--- a/net/sunrpc/clnt.c
+++ b/net/sunrpc/clnt.c
@@ -53,6 +53,7 @@
static void call_encode(struct rpc_task *task);
static void call_decode(struct rpc_task *task);
static void call_bind(struct rpc_task *task);
+static void call_bind_status(struct rpc_task *task);
static void call_transmit(struct rpc_task *task);
static void call_status(struct rpc_task *task);
static void call_refresh(struct rpc_task *task);
@@ -734,43 +735,94 @@
call_bind(struct rpc_task *task)
{
struct rpc_clnt *clnt = task->tk_client;
- struct rpc_xprt *xprt = clnt->cl_xprt;
- dprintk("RPC: %4d call_bind xprt %p %s connected\n", task->tk_pid,
- xprt, (xprt_connected(xprt) ? "is" : "is not"));
+ dprintk("RPC: %4d call_bind (status %d)\n",
+ task->tk_pid, task->tk_status);
- task->tk_action = (xprt_connected(xprt)) ? call_transmit : call_connect;
-
+ task->tk_action = call_connect;
if (!clnt->cl_port) {
- task->tk_action = call_connect;
+ task->tk_action = call_bind_status;
task->tk_timeout = RPC_CONNECT_TIMEOUT;
rpc_getport(task, clnt);
}
}
/*
- * 4a. Connect to the RPC server (TCP case)
+ * 4a. Sort out bind result
+ */
+static void
+call_bind_status(struct rpc_task *task)
+{
+ int status = -EACCES;
+
+ if (task->tk_status >= 0) {
+ dprintk("RPC: %4d call_bind_status (status %d)\n",
+ task->tk_pid, task->tk_status);
+ task->tk_status = 0;
+ task->tk_action = call_connect;
+ return;
+ }
+
+ switch (task->tk_status) {
+ case -EACCES:
+ dprintk("RPC: %4d remote rpcbind: RPC program/version unavailable\n",
+ task->tk_pid);
+ break;
+ case -ETIMEDOUT:
+ dprintk("RPC: %4d rpcbind request timed out\n",
+ task->tk_pid);
+ if (RPC_IS_SOFT(task)) {
+ status = -EIO;
+ break;
+ }
+ goto retry_bind;
+ case -EPFNOSUPPORT:
+ dprintk("RPC: %4d remote rpcbind service unavailable\n",
+ task->tk_pid);
+ break;
+ case -EPROTONOSUPPORT:
+ dprintk("RPC: %4d remote rpcbind version 2 unavailable\n",
+ task->tk_pid);
+ break;
+ default:
+ dprintk("RPC: %4d unrecognized rpcbind error (%d)\n",
+ task->tk_pid, -task->tk_status);
+ status = -EIO;
+ break;
+ }
+
+ rpc_exit(task, status);
+ return;
+
+retry_bind:
+ task->tk_status = 0;
+ task->tk_action = call_bind;
+ return;
+}
+
+/*
+ * 4b. Connect to the RPC server
*/
static void
call_connect(struct rpc_task *task)
{
- struct rpc_clnt *clnt = task->tk_client;
+ struct rpc_xprt *xprt = task->tk_xprt;
- dprintk("RPC: %4d call_connect status %d\n",
- task->tk_pid, task->tk_status);
+ dprintk("RPC: %4d call_connect xprt %p %s connected\n",
+ task->tk_pid, xprt,
+ (xprt_connected(xprt) ? "is" : "is not"));
- if (xprt_connected(clnt->cl_xprt)) {
- task->tk_action = call_transmit;
- return;
+ task->tk_action = call_transmit;
+ if (!xprt_connected(xprt)) {
+ task->tk_action = call_connect_status;
+ if (task->tk_status < 0)
+ return;
+ xprt_connect(task);
}
- task->tk_action = call_connect_status;
- if (task->tk_status < 0)
- return;
- xprt_connect(task);
}
/*
- * 4b. Sort out connect result
+ * 4c. Sort out connect result
*/
static void
call_connect_status(struct rpc_task *task)
@@ -778,6 +830,9 @@
struct rpc_clnt *clnt = task->tk_client;
int status = task->tk_status;
+ dprintk("RPC: %5u call_connect_status (status %d)\n",
+ task->tk_pid, task->tk_status);
+
task->tk_status = 0;
if (status >= 0) {
clnt->cl_stats->netreconn++;
@@ -785,17 +840,19 @@
return;
}
- /* Something failed: we may have to rebind */
+ /* Something failed: remote service port may have changed */
if (clnt->cl_autobind)
clnt->cl_port = 0;
+
switch (status) {
case -ENOTCONN:
case -ETIMEDOUT:
case -EAGAIN:
- task->tk_action = (clnt->cl_port == 0) ? call_bind : call_connect;
+ task->tk_action = call_bind;
break;
default:
rpc_exit(task, -EIO);
+ break;
}
}