Merge tag 'nfsd-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux

Pull nfsd updates from Chuck Lever:
 "Bruce has announced he is leaving Red Hat at the end of the month and
  is stepping back from his role as NFSD co-maintainer. As a result,
  this includes a patch removing him from the MAINTAINERS file.

  There is one patch in here that Jeff Layton was carrying in the locks
  tree. Since he had only one for this cycle, he asked us to send it to
  you via the nfsd tree.

  There continues to be 0-day reports from Robert Morris @mit. This time
  we include a fix for a crash in the COPY_NOTIFY operation.

  Highlights:
   - Bruce steps down as NFSD maintainer
   - Prepare for dynamic nfsd thread management
   - More work on supporting re-exporting NFS mounts
   - One fs/locks patch on behalf of Jeff Layton

  Notable bug fixes:
   - Fix zero-length NFSv3 WRITEs
   - Fix directory cinfo on FS's that do not support iversion
   - Fix WRITE verifiers for stable writes
   - Fix crash on COPY_NOTIFY with a special state ID"

* tag 'nfsd-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (51 commits)
  SUNRPC: Fix sockaddr handling in svcsock_accept_class trace points
  SUNRPC: Fix sockaddr handling in the svc_xprt_create_error trace point
  fs/locks: fix fcntl_getlk64/fcntl_setlk64 stub prototypes
  nfsd: fix crash on COPY_NOTIFY with special stateid
  MAINTAINERS: remove bfields
  NFSD: Move fill_pre_wcc() and fill_post_wcc()
  Revert "nfsd: skip some unnecessary stats in the v4 case"
  NFSD: Trace boot verifier resets
  NFSD: Rename boot verifier functions
  NFSD: Clean up the nfsd_net::nfssvc_boot field
  NFSD: Write verifier might go backwards
  nfsd: Add a tracepoint for errors in nfsd4_clone_file_range()
  NFSD: De-duplicate net_generic(nf->nf_net, nfsd_net_id)
  NFSD: De-duplicate net_generic(SVC_NET(rqstp), nfsd_net_id)
  NFSD: Clean up nfsd_vfs_write()
  nfsd: Replace use of rwsem with errseq_t
  NFSD: Fix verifier returned in stable WRITEs
  nfsd: Retry once in nfsd_open on an -EOPENSTALE return
  nfsd: Add errno mapping for EREMOTEIO
  nfsd: map EBADF
  ...

Author: torvalds

MAINTAINERS

@@ -7417,7 +7417,6 @@ F:	include/uapi/scsi/fc/
 
 FILE LOCKING (flock() and fcntl()/lockf())
 M:	Jeff Layton <[email protected]>
-M:	"J. Bruce Fields" <[email protected]>
 L:	[email protected]
 S:	Maintained
 F:	fs/fcntl.c
@@ -10428,12 +10427,11 @@ S:	Odd Fixes
 W:	http://kernelnewbies.org/KernelJanitors
 
 KERNEL NFSD, SUNRPC, AND LOCKD SERVERS
-M:	"J. Bruce Fields" <[email protected]>
 M:	Chuck Lever <[email protected]>
 L:	[email protected]
 S:	Supported
 W:	http://nfs.sourceforge.net/
-T:	git git://linux-nfs.org/~bfields/linux.git
+T:	git git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux.git
 F:	fs/lockd/
 F:	fs/nfs_common/
 F:	fs/nfsd/

fs/lockd/svc.c

@@ -54,13 +54,9 @@ EXPORT_SYMBOL_GPL(nlmsvc_ops);
 
 static DEFINE_MUTEX(nlmsvc_mutex);
 static unsigned int		nlmsvc_users;
-static struct task_struct	*nlmsvc_task;
-static struct svc_rqst		*nlmsvc_rqst;
+static struct svc_serv		*nlmsvc_serv;
 unsigned long			nlmsvc_timeout;
 
-static atomic_t nlm_ntf_refcnt = ATOMIC_INIT(0);
-static DECLARE_WAIT_QUEUE_HEAD(nlm_ntf_wq);
-
 unsigned int lockd_net_id;
 
 /*
@@ -184,7 +180,12 @@ lockd(void *vrqstp)
 	nlm_shutdown_hosts();
 	cancel_delayed_work_sync(&ln->grace_period_end);
 	locks_end_grace(&ln->lockd_manager);
-	return 0;
+
+	dprintk("lockd_down: service stopped\n");
+
+	svc_exit_thread(rqstp);
+
+	module_put_and_exit(0);
 }
 
 static int create_lockd_listener(struct svc_serv *serv, const char *name,
@@ -290,8 +291,8 @@ static void lockd_down_net(struct svc_serv *serv, struct net *net)
 				__func__, net->ns.inum);
 		}
 	} else {
-		pr_err("%s: no users! task=%p, net=%x\n",
-			__func__, nlmsvc_task, net->ns.inum);
+		pr_err("%s: no users! net=%x\n",
+			__func__, net->ns.inum);
 		BUG();
 	}
 }
@@ -302,20 +303,16 @@ static int lockd_inetaddr_event(struct notifier_block *this,
 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
 	struct sockaddr_in sin;
 
-	if ((event != NETDEV_DOWN) ||
-	    !atomic_inc_not_zero(&nlm_ntf_refcnt))
+	if (event != NETDEV_DOWN)
 		goto out;
 
-	if (nlmsvc_rqst) {
+	if (nlmsvc_serv) {
 		dprintk("lockd_inetaddr_event: removed %pI4\n",
 			&ifa->ifa_local);
 		sin.sin_family = AF_INET;
 		sin.sin_addr.s_addr = ifa->ifa_local;
-		svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
-			(struct sockaddr *)&sin);
+		svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin);
 	}
-	atomic_dec(&nlm_ntf_refcnt);
-	wake_up(&nlm_ntf_wq);
 
 out:
 	return NOTIFY_DONE;
@@ -332,21 +329,17 @@ static int lockd_inet6addr_event(struct notifier_block *this,
 	struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)ptr;
 	struct sockaddr_in6 sin6;
 
-	if ((event != NETDEV_DOWN) ||
-	    !atomic_inc_not_zero(&nlm_ntf_refcnt))
+	if (event != NETDEV_DOWN)
 		goto out;
 
-	if (nlmsvc_rqst) {
+	if (nlmsvc_serv) {
 		dprintk("lockd_inet6addr_event: removed %pI6\n", &ifa->addr);
 		sin6.sin6_family = AF_INET6;
 		sin6.sin6_addr = ifa->addr;
 		if (ipv6_addr_type(&sin6.sin6_addr) & IPV6_ADDR_LINKLOCAL)
 			sin6.sin6_scope_id = ifa->idev->dev->ifindex;
-		svc_age_temp_xprts_now(nlmsvc_rqst->rq_server,
-			(struct sockaddr *)&sin6);
+		svc_age_temp_xprts_now(nlmsvc_serv, (struct sockaddr *)&sin6);
 	}
-	atomic_dec(&nlm_ntf_refcnt);
-	wake_up(&nlm_ntf_wq);
 
 out:
 	return NOTIFY_DONE;
@@ -357,86 +350,22 @@ static struct notifier_block lockd_inet6addr_notifier = {
 };
 #endif
 
-static void lockd_unregister_notifiers(void)
-{
-	unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
-#if IS_ENABLED(CONFIG_IPV6)
-	unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
-#endif
-	wait_event(nlm_ntf_wq, atomic_read(&nlm_ntf_refcnt) == 0);
-}
-
-static void lockd_svc_exit_thread(void)
-{
-	atomic_dec(&nlm_ntf_refcnt);
-	lockd_unregister_notifiers();
-	svc_exit_thread(nlmsvc_rqst);
-}
-
-static int lockd_start_svc(struct svc_serv *serv)
-{
-	int error;
-
-	if (nlmsvc_rqst)
-		return 0;
-
-	/*
-	 * Create the kernel thread and wait for it to start.
-	 */
-	nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0], NUMA_NO_NODE);
-	if (IS_ERR(nlmsvc_rqst)) {
-		error = PTR_ERR(nlmsvc_rqst);
-		printk(KERN_WARNING
-			"lockd_up: svc_rqst allocation failed, error=%d\n",
-			error);
-		lockd_unregister_notifiers();
-		goto out_rqst;
-	}
-
-	atomic_inc(&nlm_ntf_refcnt);
-	svc_sock_update_bufs(serv);
-	serv->sv_maxconn = nlm_max_connections;
-
-	nlmsvc_task = kthread_create(lockd, nlmsvc_rqst, "%s", serv->sv_name);
-	if (IS_ERR(nlmsvc_task)) {
-		error = PTR_ERR(nlmsvc_task);
-		printk(KERN_WARNING
-			"lockd_up: kthread_run failed, error=%d\n", error);
-		goto out_task;
-	}
-	nlmsvc_rqst->rq_task = nlmsvc_task;
-	wake_up_process(nlmsvc_task);
-
-	dprintk("lockd_up: service started\n");
-	return 0;
-
-out_task:
-	lockd_svc_exit_thread();
-	nlmsvc_task = NULL;
-out_rqst:
-	nlmsvc_rqst = NULL;
-	return error;
-}
-
 static const struct svc_serv_ops lockd_sv_ops = {
 	.svo_shutdown		= svc_rpcb_cleanup,
+	.svo_function		= lockd,
 	.svo_enqueue_xprt	= svc_xprt_do_enqueue,
+	.svo_module		= THIS_MODULE,
 };
 
-static struct svc_serv *lockd_create_svc(void)
+static int lockd_get(void)
 {
 	struct svc_serv *serv;
+	int error;
 
-	/*
-	 * Check whether we're already up and running.
-	 */
-	if (nlmsvc_rqst) {
-		/*
-		 * Note: increase service usage, because later in case of error
-		 * svc_destroy() will be called.
-		 */
-		svc_get(nlmsvc_rqst->rq_server);
-		return nlmsvc_rqst->rq_server;
+	if (nlmsvc_serv) {
+		svc_get(nlmsvc_serv);
+		nlmsvc_users++;
+		return 0;
 	}
 
 	/*
@@ -454,51 +383,63 @@ static struct svc_serv *lockd_create_svc(void)
 	serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, &lockd_sv_ops);
 	if (!serv) {
 		printk(KERN_WARNING "lockd_up: create service failed\n");
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 	}
+
+	serv->sv_maxconn = nlm_max_connections;
+	error = svc_set_num_threads(serv, NULL, 1);
+	/* The thread now holds the only reference */
+	svc_put(serv);
+	if (error < 0)
+		return error;
+
+	nlmsvc_serv = serv;
 	register_inetaddr_notifier(&lockd_inetaddr_notifier);
 #if IS_ENABLED(CONFIG_IPV6)
 	register_inet6addr_notifier(&lockd_inet6addr_notifier);
 #endif
 	dprintk("lockd_up: service created\n");
-	return serv;
+	nlmsvc_users++;
+	return 0;
+}
+
+static void lockd_put(void)
+{
+	if (WARN(nlmsvc_users <= 0, "lockd_down: no users!\n"))
+		return;
+	if (--nlmsvc_users)
+		return;
+
+	unregister_inetaddr_notifier(&lockd_inetaddr_notifier);
+#if IS_ENABLED(CONFIG_IPV6)
+	unregister_inet6addr_notifier(&lockd_inet6addr_notifier);
+#endif
+
+	svc_set_num_threads(nlmsvc_serv, NULL, 0);
+	nlmsvc_serv = NULL;
+	dprintk("lockd_down: service destroyed\n");
 }
 
 /*
  * Bring up the lockd process if it's not already up.
  */
 int lockd_up(struct net *net, const struct cred *cred)
 {
-	struct svc_serv *serv;
 	int error;
 
 	mutex_lock(&nlmsvc_mutex);
 
-	serv = lockd_create_svc();
-	if (IS_ERR(serv)) {
-		error = PTR_ERR(serv);
-		goto err_create;
-	}
+	error = lockd_get();
+	if (error)
+		goto err;
 
-	error = lockd_up_net(serv, net, cred);
+	error = lockd_up_net(nlmsvc_serv, net, cred);
 	if (error < 0) {
-		lockd_unregister_notifiers();
-		goto err_put;
+		lockd_put();
+		goto err;
 	}
 
-	error = lockd_start_svc(serv);
-	if (error < 0) {
-		lockd_down_net(serv, net);
-		goto err_put;
-	}
-	nlmsvc_users++;
-	/*
-	 * Note: svc_serv structures have an initial use count of 1,
-	 * so we exit through here on both success and failure.
-	 */
-err_put:
-	svc_destroy(serv);
-err_create:
+err:
 	mutex_unlock(&nlmsvc_mutex);
 	return error;
 }
@@ -511,27 +452,8 @@ void
 lockd_down(struct net *net)
 {
 	mutex_lock(&nlmsvc_mutex);
-	lockd_down_net(nlmsvc_rqst->rq_server, net);
-	if (nlmsvc_users) {
-		if (--nlmsvc_users)
-			goto out;
-	} else {
-		printk(KERN_ERR "lockd_down: no users! task=%p\n",
-			nlmsvc_task);
-		BUG();
-	}
-
-	if (!nlmsvc_task) {
-		printk(KERN_ERR "lockd_down: no lockd running.\n");
-		BUG();
-	}
-	kthread_stop(nlmsvc_task);
-	dprintk("lockd_down: service stopped\n");
-	lockd_svc_exit_thread();
-	dprintk("lockd_down: service destroyed\n");
-	nlmsvc_task = NULL;
-	nlmsvc_rqst = NULL;
-out:
+	lockd_down_net(nlmsvc_serv, net);
+	lockd_put();
 	mutex_unlock(&nlmsvc_mutex);
 }
 EXPORT_SYMBOL_GPL(lockd_down);

fs/lockd/svclock.c

@@ -470,8 +470,10 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
 	    struct nlm_host *host, struct nlm_lock *lock, int wait,
 	    struct nlm_cookie *cookie, int reclaim)
 {
-	struct nlm_block	*block = NULL;
+#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 	struct inode		*inode = nlmsvc_file_inode(file);
+#endif
+	struct nlm_block	*block = NULL;
 	int			error;
 	int			mode;
 	int			async_block = 0;
@@ -484,7 +486,7 @@ nlmsvc_lock(struct svc_rqst *rqstp, struct nlm_file *file,
 				(long long)lock->fl.fl_end,
 				wait);
 
-	if (inode->i_sb->s_export_op->flags & EXPORT_OP_SYNC_LOCKS) {
+	if (nlmsvc_file_file(file)->f_op->lock) {
 		async_block = wait;
 		wait = 0;
 	}