1 files changed, 48 insertions, 45 deletions

diff --git a/fs/nfs/callback.c b/fs/nfs/callback.c
index 66648dd92d9..5606ae3d72d 100644
--- a/fs/nfs/callback.c
+++ b/fs/nfs/callback.c
@@ -15,6 +15,7 @@
 #include <linux/nfs_fs.h>
 #include <linux/mutex.h>
 #include <linux/freezer.h>
+#include <linux/kthread.h>
 
 #include <net/inet_sock.h>
 
@@ -27,9 +28,7 @@
 struct nfs_callback_data {
 	unsigned int users;
 	struct svc_serv *serv;
-	pid_t pid;
-	struct completion started;
-	struct completion stopped;
+	struct task_struct *task;
 };
 
 static struct nfs_callback_data nfs_callback_info;
@@ -57,48 +56,44 @@ module_param_call(callback_tcpport, param_set_port, param_get_int,
 /*
  * This is the callback kernel thread.
  */
-static void nfs_callback_svc(struct svc_rqst *rqstp)
+static int
+nfs_callback_svc(void *vrqstp)
 {
-	int err;
+	int err, preverr = 0;
+	struct svc_rqst *rqstp = vrqstp;
 
-	__module_get(THIS_MODULE);
-	lock_kernel();
-
-	nfs_callback_info.pid = current->pid;
-	daemonize("nfsv4-svc");
-	/* Process request with signals blocked, but allow SIGKILL.  */
-	allow_signal(SIGKILL);
 	set_freezable();
 
-	complete(&nfs_callback_info.started);
-
-	for(;;) {
-		if (signalled()) {
-			if (nfs_callback_info.users == 0)
-				break;
-			flush_signals(current);
-		}
+	/*
+	 * FIXME: do we really need to run this under the BKL? If so, please
+	 * add a comment about what it's intended to protect.
+	 */
+	lock_kernel();
+	while (!kthread_should_stop()) {
 		/*
 		 * Listen for a request on the socket
 		 */
 		err = svc_recv(rqstp, MAX_SCHEDULE_TIMEOUT);
-		if (err == -EAGAIN || err == -EINTR)
+		if (err == -EAGAIN || err == -EINTR) {
+			preverr = err;
 			continue;
+		}
 		if (err < 0) {
-			printk(KERN_WARNING
-					"%s: terminating on error %d\n",
-					__FUNCTION__, -err);
-			break;
+			if (err != preverr) {
+				printk(KERN_WARNING "%s: unexpected error "
+					"from svc_recv (%d)\n", __func__, err);
+				preverr = err;
+			}
+			schedule_timeout_uninterruptible(HZ);
+			continue;
 		}
+		preverr = err;
 		svc_process(rqstp);
 	}
-
-	flush_signals(current);
-	svc_exit_thread(rqstp);
-	nfs_callback_info.pid = 0;
-	complete(&nfs_callback_info.stopped);
 	unlock_kernel();
-	module_put_and_exit(0);
+	nfs_callback_info.task = NULL;
+	svc_exit_thread(rqstp);
+	return 0;
 }
 
 /*
@@ -107,14 +102,13 @@ static void nfs_callback_svc(struct svc_rqst *rqstp)
 int nfs_callback_up(void)
 {
 	struct svc_serv *serv = NULL;
+	struct svc_rqst *rqstp;
 	int ret = 0;
 
 	lock_kernel();
 	mutex_lock(&nfs_callback_mutex);
-	if (nfs_callback_info.users++ || nfs_callback_info.pid != 0)
+	if (nfs_callback_info.users++ || nfs_callback_info.task != NULL)
 		goto out;
-	init_completion(&nfs_callback_info.started);
-	init_completion(&nfs_callback_info.stopped);
 	serv = svc_create(&nfs4_callback_program, NFS4_CALLBACK_BUFSIZE, NULL);
 	ret = -ENOMEM;
 	if (!serv)
@@ -127,15 +121,28 @@ int nfs_callback_up(void)
 	nfs_callback_tcpport = ret;
 	dprintk("Callback port = 0x%x\n", nfs_callback_tcpport);
 
-	ret = svc_create_thread(nfs_callback_svc, serv);
-	if (ret < 0)
+	rqstp = svc_prepare_thread(serv, &serv->sv_pools[0]);
+	if (IS_ERR(rqstp)) {
+		ret = PTR_ERR(rqstp);
 		goto out_err;
+	}
+
+	svc_sock_update_bufs(serv);
 	nfs_callback_info.serv = serv;
-	wait_for_completion(&nfs_callback_info.started);
+
+	nfs_callback_info.task = kthread_run(nfs_callback_svc, rqstp,
+					     "nfsv4-svc");
+	if (IS_ERR(nfs_callback_info.task)) {
+		ret = PTR_ERR(nfs_callback_info.task);
+		nfs_callback_info.serv = NULL;
+		nfs_callback_info.task = NULL;
+		svc_exit_thread(rqstp);
+		goto out_err;
+	}
 out:
 	/*
 	 * svc_create creates the svc_serv with sv_nrthreads == 1, and then
-	 * svc_create_thread increments that. So we need to call svc_destroy
+	 * svc_prepare_thread increments that. So we need to call svc_destroy
 	 * on both success and failure so that the refcount is 1 when the
 	 * thread exits.
 	 */
@@ -152,19 +159,15 @@ out_err:
 }
 
 /*
- * Kill the server process if it is not already up.
+ * Kill the server process if it is not already down.
  */
 void nfs_callback_down(void)
 {
 	lock_kernel();
 	mutex_lock(&nfs_callback_mutex);
 	nfs_callback_info.users--;
-	do {
-		if (nfs_callback_info.users != 0 || nfs_callback_info.pid == 0)
-			break;
-		if (kill_proc(nfs_callback_info.pid, SIGKILL, 1) < 0)
-			break;
-	} while (wait_for_completion_timeout(&nfs_callback_info.stopped, 5*HZ) == 0);
+	if (nfs_callback_info.users == 0 && nfs_callback_info.task != NULL)
+		kthread_stop(nfs_callback_info.task);
 	mutex_unlock(&nfs_callback_mutex);
 	unlock_kernel();
 }