SUNRPC: Yet more RPC cleanups

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

include/linux/sunrpc/sched.h

@@ -233,6 +233,7 @@ struct rpc_task *rpc_new_child(struct rpc_clnt *, struct rpc_task *parent);
 void		rpc_init_task(struct rpc_task *, struct rpc_clnt *,
 					rpc_action exitfunc, int flags);
 void		rpc_release_task(struct rpc_task *);
+void		rpc_exit_task(struct rpc_task *);
 void		rpc_killall_tasks(struct rpc_clnt *);
 int		rpc_execute(struct rpc_task *);
 void		rpc_run_child(struct rpc_task *parent, struct rpc_task *child,
@@ -259,7 +260,7 @@ void		rpc_destroy_mempool(void);
 static inline void rpc_exit(struct rpc_task *task, int status)
 {
 	task->tk_status = status;
-	task->tk_action = NULL;
+	task->tk_action = rpc_exit_task;
 }
 
 #ifdef RPC_DEBUG

net/sunrpc/clnt.c

@@ -511,7 +511,7 @@ rpc_call_setup(struct rpc_task *task, struct rpc_message *msg, int flags)
 	if (task->tk_status == 0)
 		task->tk_action = call_start;
 	else
-		task->tk_action = NULL;
+		task->tk_action = rpc_exit_task;
 }
 
 void
@@ -892,7 +892,7 @@ call_transmit(struct rpc_task *task)
 	if (task->tk_status < 0)
 		return;
 	if (!task->tk_msg.rpc_proc->p_decode) {
-		task->tk_action = NULL;
+		task->tk_action = rpc_exit_task;
 		rpc_wake_up_task(task);
 	}
 	return;
@@ -1039,13 +1039,14 @@ call_decode(struct rpc_task *task)
 				sizeof(req->rq_rcv_buf)) != 0);
 
 	/* Verify the RPC header */
-	if (!(p = call_verify(task))) {
-		if (task->tk_action == NULL)
-			return;
-		goto out_retry;
+	p = call_verify(task);
+	if (IS_ERR(p)) {
+		if (p == ERR_PTR(-EAGAIN))
+			goto out_retry;
+		return;
 	}
 
-	task->tk_action = NULL;
+	task->tk_action = rpc_exit_task;
 
 	if (decode)
 		task->tk_status = rpcauth_unwrap_resp(task, decode, req, p,
@@ -1138,7 +1139,7 @@ call_verify(struct rpc_task *task)
 
 	if ((n = ntohl(*p++)) != RPC_REPLY) {
 		printk(KERN_WARNING "call_verify: not an RPC reply: %x\n", n);
-		goto out_retry;
+		goto out_garbage;
 	}
 	if ((n = ntohl(*p++)) != RPC_MSG_ACCEPTED) {
 		if (--len < 0)
@@ -1168,7 +1169,7 @@ call_verify(struct rpc_task *task)
 							task->tk_pid);
 			rpcauth_invalcred(task);
 			task->tk_action = call_refresh;
-			return NULL;
+			goto out_retry;
 		case RPC_AUTH_BADCRED:
 		case RPC_AUTH_BADVERF:
 			/* possibly garbled cred/verf? */
@@ -1178,7 +1179,7 @@ call_verify(struct rpc_task *task)
 			dprintk("RPC: %4d call_verify: retry garbled creds\n",
 							task->tk_pid);
 			task->tk_action = call_bind;
-			return NULL;
+			goto out_retry;
 		case RPC_AUTH_TOOWEAK:
 			printk(KERN_NOTICE "call_verify: server requires stronger "
 			       "authentication.\n");
@@ -1193,7 +1194,7 @@ call_verify(struct rpc_task *task)
 	}
 	if (!(p = rpcauth_checkverf(task, p))) {
 		printk(KERN_WARNING "call_verify: auth check failed\n");
-		goto out_retry;		/* bad verifier, retry */
+		goto out_garbage;		/* bad verifier, retry */
 	}
 	len = p - (u32 *)iov->iov_base - 1;
 	if (len < 0)
@@ -1230,23 +1231,24 @@ call_verify(struct rpc_task *task)
 		/* Also retry */
 	}
 
-out_retry:
+out_garbage:
 	task->tk_client->cl_stats->rpcgarbage++;
 	if (task->tk_garb_retry) {
 		task->tk_garb_retry--;
 		dprintk("RPC %s: retrying %4d\n", __FUNCTION__, task->tk_pid);
 		task->tk_action = call_bind;
-		return NULL;
+out_retry:
+		return ERR_PTR(-EAGAIN);
 	}
 	printk(KERN_WARNING "RPC %s: retry failed, exit EIO\n", __FUNCTION__);
 out_eio:
 	error = -EIO;
 out_err:
 	rpc_exit(task, error);
-	return NULL;
+	return ERR_PTR(error);
 out_overflow:
 	printk(KERN_WARNING "RPC %s: server reply was truncated.\n", __FUNCTION__);
-	goto out_retry;
+	goto out_garbage;
 }
 
 static int rpcproc_encode_null(void *rqstp, u32 *data, void *obj)

net/sunrpc/pmap_clnt.c

@@ -90,8 +90,7 @@ rpc_getport(struct rpc_task *task, struct rpc_clnt *clnt)
 	map->pm_binding = 0;
 	rpc_wake_up(&map->pm_bindwait);
 	spin_unlock(&pmap_lock);
-	task->tk_status = -EIO;
-	task->tk_action = NULL;
+	rpc_exit(task, -EIO);
 }
 
 #ifdef CONFIG_ROOT_NFS
@@ -138,11 +137,10 @@ pmap_getport_done(struct rpc_task *task)
 			task->tk_pid, task->tk_status, clnt->cl_port);
 	if (task->tk_status < 0) {
 		/* Make the calling task exit with an error */
-		task->tk_action = NULL;
+		task->tk_action = rpc_exit_task;
 	} else if (clnt->cl_port == 0) {
 		/* Program not registered */
-		task->tk_status = -EACCES;
-		task->tk_action = NULL;
+		rpc_exit(task, -EACCES);
 	} else {
 		/* byte-swap port number first */
 		clnt->cl_port = htons(clnt->cl_port);

net/sunrpc/sched.c

@@ -555,28 +555,22 @@ __rpc_atrun(struct rpc_task *task)
 }
 
 /*
- * Helper that calls task->tk_exit if it exists and then returns
- * true if we should exit __rpc_execute.
+ * Helper that calls task->tk_exit if it exists
  */
-static inline int __rpc_do_exit(struct rpc_task *task)
+void rpc_exit_task(struct rpc_task *task)
 {
+	task->tk_action = NULL;
 	if (task->tk_exit != NULL) {
-		lock_kernel();
 		task->tk_exit(task);
-		unlock_kernel();
-		/* If tk_action is non-null, we should restart the call */
 		if (task->tk_action != NULL) {
-			if (!RPC_ASSASSINATED(task)) {
-				/* Release RPC slot and buffer memory */
-				xprt_release(task);
-				rpc_free(task);
-				return 0;
-			}
-			printk(KERN_ERR "RPC: dead task tried to walk away.\n");
+			WARN_ON(RPC_ASSASSINATED(task));
+			/* Always release the RPC slot and buffer memory */
+			xprt_release(task);
+			rpc_free(task);
 		}
 	}
-	return 1;
 }
+EXPORT_SYMBOL(rpc_exit_task);
 
 static int rpc_wait_bit_interruptible(void *word)
 {
@@ -631,12 +625,11 @@ static int __rpc_execute(struct rpc_task *task)
 		 * by someone else.
 		 */
 		if (!RPC_IS_QUEUED(task)) {
-			if (task->tk_action != NULL) {
-				lock_kernel();
-				task->tk_action(task);
-				unlock_kernel();
-			} else if (__rpc_do_exit(task))
+			if (task->tk_action == NULL)
 				break;
+			lock_kernel();
+			task->tk_action(task);
+			unlock_kernel();
 		}
 
 		/*