25 files changed, 155 insertions, 116 deletions

diff --git a/fs/nfs/Kconfig b/fs/nfs/Kconfig
index f81a729c00e9..195c1ea6151a 100644
--- a/fs/nfs/Kconfig
+++ b/fs/nfs/Kconfig
@@ -72,7 +72,7 @@ config NFS_V3_ACL
           If unsure, say N.
 
 config NFS_V4
-        bool "NFS client support for NFS version 4"
+        tristate "NFS client support for NFS version 4"
         depends on NFS_FS
         select SUNRPC_GSS
         select KEYS
diff --git a/fs/nfs/Makefile b/fs/nfs/Makefile
index 01846edc5c94..8bf3a3f6925a 100644
--- a/fs/nfs/Makefile
+++ b/fs/nfs/Makefile
@@ -9,17 +9,7 @@ nfs-y 			:= client.o dir.o file.o getroot.o inode.o super.o \
                            write.o namespace.o mount_clnt.o \
                            dns_resolve.o cache_lib.o
 nfs-$(CONFIG_ROOT_NFS)  += nfsroot.o
-nfs-$(CONFIG_NFS_V4)    += nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o \
-                           nfs4super.o nfs4file.o delegation.o idmap.o \
-                           callback.o callback_xdr.o callback_proc.o \
-                           nfs4namespace.o nfs4getroot.o nfs4client.o
-nfs-$(CONFIG_NFS_V4_1)  += pnfs.o pnfs_dev.o
-
-ifeq ($(CONFIG_SYSCTL), y)
-nfs-y += sysctl.o
-nfs-$(CONFIG_NFS_V4) += nfs4sysctl.o
-endif
-
+nfs-$(CONFIG_SYSCTL)    += sysctl.o
 nfs-$(CONFIG_NFS_FSCACHE) += fscache.o fscache-index.o
 
 obj-$(CONFIG_NFS_V2) += nfs2.o
@@ -29,6 +19,13 @@ obj-$(CONFIG_NFS_V3) += nfs3.o
 nfs3-y := nfs3super.o nfs3client.o nfs3proc.o nfs3xdr.o
 nfs3-$(CONFIG_NFS_V3_ACL) += nfs3acl.o
 
+obj-$(CONFIG_NFS_V4) += nfs4.o
+nfs4-y := nfs4proc.o nfs4xdr.o nfs4state.o nfs4renewd.o nfs4super.o nfs4file.o \
+          delegation.o idmap.o callback.o callback_xdr.o callback_proc.o \
+          nfs4namespace.o nfs4getroot.o nfs4client.o
+nfs4-$(CONFIG_SYSCTL)   += nfs4sysctl.o
+nfs4-$(CONFIG_NFS_V4_1) += pnfs.o pnfs_dev.o
+
 obj-$(CONFIG_PNFS_FILE_LAYOUT) += nfs_layout_nfsv41_files.o
 nfs_layout_nfsv41_files-y := nfs4filelayout.o nfs4filelayoutdev.o
 
diff --git a/fs/nfs/callback.h b/fs/nfs/callback.h
index a5527c90a5aa..b44d7b128b71 100644
--- a/fs/nfs/callback.h
+++ b/fs/nfs/callback.h
@@ -192,7 +192,7 @@ extern __be32 nfs4_callback_getattr(struct cb_getattrargs *args,
                                     struct cb_process_state *cps);
 extern __be32 nfs4_callback_recall(struct cb_recallargs *args, void *dummy,
                                    struct cb_process_state *cps);
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 extern int nfs_callback_up(u32 minorversion, struct rpc_xprt *xprt);
 extern void nfs_callback_down(int minorversion);
 extern int nfs4_validate_delegation_stateid(struct nfs_delegation *delegation,
diff --git a/fs/nfs/client.c b/fs/nfs/client.c
index 8687b6b6edc1..9fc0d9dfc91b 100644
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -143,24 +143,6 @@ void unregister_nfs_version(struct nfs_subversion *nfs)
 EXPORT_SYMBOL_GPL(unregister_nfs_version);
 
 /*
- * Preload all configured NFS versions during module init.
- * This function should be edited after each protocol is converted,
- * and eventually removed.
- */
-int __init nfs_register_versions(void)
-{
-        return init_nfs_v4();
-}
-
-/*
- * Remove each pre-loaded NFS version
- */
-void nfs_unregister_versions(void)
-{
-        exit_nfs_v4();
-}
-
-/*
  * Allocate a shared client record
  *
  * Since these are allocated/deallocated very rarely, we don't
@@ -214,7 +196,7 @@ error_0:
 }
 EXPORT_SYMBOL_GPL(nfs_alloc_client);
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 /* idr_remove_all is not needed as all id's are removed by nfs_put_client */
 void nfs_cleanup_cb_ident_idr(struct net *net)
 {
@@ -390,6 +372,7 @@ int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
         }
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_sockaddr_match_ipaddr);
 #endif /* CONFIG_NFS_V4_1 */
 
 /*
@@ -456,6 +439,7 @@ int nfs_wait_client_init_complete(const struct nfs_client *clp)
         return wait_event_killable(nfs_client_active_wq,
                         nfs_client_init_is_complete(clp));
 }
+EXPORT_SYMBOL_GPL(nfs_wait_client_init_complete);
 
 /*
  * Found an existing client.  Make sure it's ready before returning.
@@ -530,6 +514,7 @@ nfs_get_client(const struct nfs_client_initdata *cl_init,
                 cl_init->hostname ?: "", PTR_ERR(new));
         return new;
 }
+EXPORT_SYMBOL_GPL(nfs_get_client);
 
 /*
  * Mark a server as ready or failed
@@ -540,6 +525,7 @@ void nfs_mark_client_ready(struct nfs_client *clp, int state)
         clp->cl_cons_state = state;
         wake_up_all(&nfs_client_active_wq);
 }
+EXPORT_SYMBOL_GPL(nfs_mark_client_ready);
 
 /*
  * Initialise the timeout values for a connection
@@ -581,6 +567,7 @@ void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
                 BUG();
         }
 }
+EXPORT_SYMBOL_GPL(nfs_init_timeout_values);
 
 /*
  * Create an RPC client handle
@@ -620,6 +607,7 @@ int nfs_create_rpc_client(struct nfs_client *clp,
         clp->cl_rpcclient = clnt;
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_create_rpc_client);
 
 /*
  * Version 2 or 3 client destruction
@@ -706,6 +694,7 @@ int nfs_init_server_rpcclient(struct nfs_server *server,
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_init_server_rpcclient);
 
 /**
  * nfs_init_client - Initialise an NFS2 or NFS3 client
@@ -932,6 +921,7 @@ out_error:
         dprintk("nfs_probe_fsinfo: error = %d\n", -error);
         return error;
 }
+EXPORT_SYMBOL_GPL(nfs_probe_fsinfo);
 
 /*
  * Copy useful information when duplicating a server record
@@ -948,6 +938,7 @@ void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *sour
         target->caps = source->caps;
         target->options = source->options;
 }
+EXPORT_SYMBOL_GPL(nfs_server_copy_userdata);
 
 void nfs_server_insert_lists(struct nfs_server *server)
 {
@@ -961,6 +952,7 @@ void nfs_server_insert_lists(struct nfs_server *server)
         spin_unlock(&nn->nfs_client_lock);
 
 }
+EXPORT_SYMBOL_GPL(nfs_server_insert_lists);
 
 static void nfs_server_remove_lists(struct nfs_server *server)
 {
@@ -1020,6 +1012,7 @@ struct nfs_server *nfs_alloc_server(void)
 
         return server;
 }
+EXPORT_SYMBOL_GPL(nfs_alloc_server);
 
 /*
  * Free up a server record
@@ -1048,6 +1041,7 @@ void nfs_free_server(struct nfs_server *server)
         nfs_release_automount_timer();
         dprintk("<-- nfs_free_server()\n");
 }
+EXPORT_SYMBOL_GPL(nfs_free_server);
 
 /*
  * Create a version 2 or 3 volume record
@@ -1193,7 +1187,7 @@ void nfs_clients_init(struct net *net)
 
         INIT_LIST_HEAD(&nn->nfs_client_list);
         INIT_LIST_HEAD(&nn->nfs_volume_list);
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         idr_init(&nn->cb_ident_idr);
 #endif
         spin_lock_init(&nn->nfs_client_lock);
diff --git a/fs/nfs/delegation.h b/fs/nfs/delegation.h
index 1f3ccd934635..bbc6a4dba0d8 100644
--- a/fs/nfs/delegation.h
+++ b/fs/nfs/delegation.h
@@ -8,7 +8,7 @@
 #ifndef FS_NFS_DELEGATION_H
 #define FS_NFS_DELEGATION_H
 
-#if defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V4)
 /*
  * NFSv4 delegation
  */
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 55438c970cbf..627f108ede23 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -936,6 +936,7 @@ void nfs_force_lookup_revalidate(struct inode *dir)
 {
         NFS_I(dir)->cache_change_attribute++;
 }
+EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate);
 
 /*
  * A check for whether or not the parent directory has changed.
@@ -1267,7 +1268,7 @@ out:
 }
 EXPORT_SYMBOL_GPL(nfs_lookup);
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 static int nfs4_lookup_revalidate(struct dentry *, unsigned int);
 
 const struct dentry_operations nfs4_dentry_operations = {
@@ -1277,6 +1278,7 @@ const struct dentry_operations nfs4_dentry_operations = {
         .d_automount    = nfs_d_automount,
         .d_release      = nfs_d_release,
 };
+EXPORT_SYMBOL_GPL(nfs4_dentry_operations);
 
 static fmode_t flags_to_mode(int flags)
 {
@@ -1419,6 +1421,7 @@ no_open:
 
         return finish_no_open(file, res);
 }
+EXPORT_SYMBOL_GPL(nfs_atomic_open);
 
 static int nfs4_lookup_revalidate(struct dentry *dentry, unsigned int flags)
 {
@@ -2142,6 +2145,7 @@ int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
 {
         return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
 }
+EXPORT_SYMBOL_GPL(nfs_may_open);
 
 int nfs_permission(struct inode *inode, int mask)
 {
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 899238156b11..b7b4f80968b5 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -460,7 +460,7 @@ static void nfs_inode_dio_write_done(struct inode *inode)
         inode_dio_done(inode);
 }
 
-#if IS_ENABLED(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
 static void nfs_direct_write_reschedule(struct nfs_direct_req *dreq)
 {
         struct nfs_pageio_descriptor desc;
diff --git a/fs/nfs/dns_resolve.c b/fs/nfs/dns_resolve.c
index b3924b8a6000..31c26c4dcc23 100644
--- a/fs/nfs/dns_resolve.c
+++ b/fs/nfs/dns_resolve.c
@@ -8,6 +8,7 @@
 
 #ifdef CONFIG_NFS_USE_KERNEL_DNS
 
+#include <linux/module.h>
 #include <linux/sunrpc/clnt.h>
 #include <linux/dns_resolver.h>
 #include "dns_resolve.h"
@@ -27,9 +28,11 @@ ssize_t nfs_dns_resolve_name(struct net *net, char *name, size_t namelen,
         kfree(ip_addr);
         return ret;
 }
+EXPORT_SYMBOL_GPL(nfs_dns_resolve_name);
 
 #else
 
+#include <linux/module.h>
 #include <linux/hash.h>
 #include <linux/string.h>
 #include <linux/kmod.h>
@@ -345,6 +348,7 @@ ssize_t nfs_dns_resolve_name(struct net *net, char *name,
                 ret = -ESRCH;
         return ret;
 }
+EXPORT_SYMBOL_GPL(nfs_dns_resolve_name);
 
 int nfs_dns_resolver_cache_init(struct net *net)
 {
diff --git a/fs/nfs/file.c b/fs/nfs/file.c
index 5b3e70389553..1557978ca7b3 100644
--- a/fs/nfs/file.c
+++ b/fs/nfs/file.c
@@ -53,6 +53,7 @@ int nfs_check_flags(int flags)
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_check_flags);
 
 /*
  * Open file
@@ -85,6 +86,7 @@ nfs_file_release(struct inode *inode, struct file *filp)
         nfs_inc_stats(inode, NFSIOS_VFSRELEASE);
         return nfs_release(inode, filp);
 }
+EXPORT_SYMBOL_GPL(nfs_file_release);
 
 /**
  * nfs_revalidate_size - Revalidate the file size
@@ -138,6 +140,7 @@ loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
 
         return generic_file_llseek(filp, offset, origin);
 }
+EXPORT_SYMBOL_GPL(nfs_file_llseek);
 
 /*
  * Flush all dirty pages, and check for write errors.
@@ -166,6 +169,7 @@ nfs_file_flush(struct file *file, fl_owner_t id)
         /* Flush writes to the server and return any errors */
         return vfs_fsync(file, 0);
 }
+EXPORT_SYMBOL_GPL(nfs_file_flush);
 
 ssize_t
 nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
@@ -190,6 +194,7 @@ nfs_file_read(struct kiocb *iocb, const struct iovec *iov,
         }
         return result;
 }
+EXPORT_SYMBOL_GPL(nfs_file_read);
 
 ssize_t
 nfs_file_splice_read(struct file *filp, loff_t *ppos,
@@ -212,6 +217,7 @@ nfs_file_splice_read(struct file *filp, loff_t *ppos,
         }
         return res;
 }
+EXPORT_SYMBOL_GPL(nfs_file_splice_read);
 
 int
 nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
@@ -233,6 +239,7 @@ nfs_file_mmap(struct file * file, struct vm_area_struct * vma)
         }
         return status;
 }
+EXPORT_SYMBOL_GPL(nfs_file_mmap);
 
 /*
  * Flush any dirty pages for this process, and check for write errors.
@@ -271,6 +278,7 @@ nfs_file_fsync_commit(struct file *file, loff_t start, loff_t end, int datasync)
                 ret = status;
         return ret;
 }
+EXPORT_SYMBOL_GPL(nfs_file_fsync_commit);
 
 static int
 nfs_file_fsync(struct file *file, loff_t start, loff_t end, int datasync)
@@ -615,6 +623,7 @@ out_swapfile:
         printk(KERN_INFO "NFS: attempt to write to active swap file!\n");
         goto out;
 }
+EXPORT_SYMBOL_GPL(nfs_file_write);
 
 ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe,
                               struct file *filp, loff_t *ppos,
@@ -646,6 +655,7 @@ ssize_t nfs_file_splice_write(struct pipe_inode_info *pipe,
                 nfs_add_stats(inode, NFSIOS_NORMALWRITTENBYTES, written);
         return ret;
 }
+EXPORT_SYMBOL_GPL(nfs_file_splice_write);
 
 static int
 do_getlk(struct file *filp, int cmd, struct file_lock *fl, int is_local)
@@ -806,6 +816,7 @@ int nfs_lock(struct file *filp, int cmd, struct file_lock *fl)
 out_err:
         return ret;
 }
+EXPORT_SYMBOL_GPL(nfs_lock);
 
 /*
  * Lock a (portion of) a file
@@ -835,6 +846,7 @@ int nfs_flock(struct file *filp, int cmd, struct file_lock *fl)
                 return do_unlk(filp, cmd, fl, is_local);
         return do_setlk(filp, cmd, fl, is_local);
 }
+EXPORT_SYMBOL_GPL(nfs_flock);
 
 /*
  * There is no protocol support for leases, so we have no way to implement
@@ -847,6 +859,7 @@ int nfs_setlease(struct file *file, long arg, struct file_lock **fl)
                         file->f_path.dentry->d_name.name, arg);
         return -EINVAL;
 }
+EXPORT_SYMBOL_GPL(nfs_setlease);
 
 const struct file_operations nfs_file_operations = {
         .llseek         = nfs_file_llseek,
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 78dfc3e895ec..2ed6138f32ad 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -82,6 +82,7 @@ int nfs_wait_bit_killable(void *word)
         freezable_schedule();
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_wait_bit_killable);
 
 /**
  * nfs_compat_user_ino64 - returns the user-visible inode number
@@ -117,6 +118,7 @@ void nfs_clear_inode(struct inode *inode)
         nfs_access_zap_cache(inode);
         nfs_fscache_release_inode_cookie(inode);
 }
+EXPORT_SYMBOL_GPL(nfs_clear_inode);
 
 void nfs_evict_inode(struct inode *inode)
 {
@@ -393,6 +395,7 @@ out_no_inode:
         dprintk("nfs_fhget: iget failed with error %ld\n", PTR_ERR(inode));
         goto out;
 }
+EXPORT_SYMBOL_GPL(nfs_fhget);
 
 #define NFS_VALID_ATTRS (ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_SIZE|ATTR_ATIME|ATTR_ATIME_SET|ATTR_MTIME|ATTR_MTIME_SET|ATTR_FILE|ATTR_OPEN)
 
@@ -655,6 +658,7 @@ struct nfs_open_context *alloc_nfs_open_context(struct dentry *dentry, fmode_t f
         ctx->mdsthreshold = NULL;
         return ctx;
 }
+EXPORT_SYMBOL_GPL(alloc_nfs_open_context);
 
 struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
 {
@@ -662,6 +666,7 @@ struct nfs_open_context *get_nfs_open_context(struct nfs_open_context *ctx)
                 atomic_inc(&ctx->lock_context.count);
         return ctx;
 }
+EXPORT_SYMBOL_GPL(get_nfs_open_context);
 
 static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
 {
@@ -689,6 +694,7 @@ void put_nfs_open_context(struct nfs_open_context *ctx)
 {
         __put_nfs_open_context(ctx, 0);
 }
+EXPORT_SYMBOL_GPL(put_nfs_open_context);
 
 /*
  * Ensure that mmap has a recent RPC credential for use when writing out
@@ -704,6 +710,7 @@ void nfs_file_set_open_context(struct file *filp, struct nfs_open_context *ctx)
         list_add(&ctx->list, &nfsi->open_files);
         spin_unlock(&inode->i_lock);
 }
+EXPORT_SYMBOL_GPL(nfs_file_set_open_context);
 
 /*
  * Given an inode, search for an open context with the desired characteristics
@@ -1497,11 +1504,12 @@ struct inode *nfs_alloc_inode(struct super_block *sb)
         nfsi->acl_access = ERR_PTR(-EAGAIN);
         nfsi->acl_default = ERR_PTR(-EAGAIN);
 #endif
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         nfsi->nfs4_acl = NULL;
 #endif /* CONFIG_NFS_V4 */
         return &nfsi->vfs_inode;
 }
+EXPORT_SYMBOL_GPL(nfs_alloc_inode);
 
 static void nfs_i_callback(struct rcu_head *head)
 {
@@ -1513,10 +1521,11 @@ void nfs_destroy_inode(struct inode *inode)
 {
         call_rcu(&inode->i_rcu, nfs_i_callback);
 }
+EXPORT_SYMBOL_GPL(nfs_destroy_inode);
 
 static inline void nfs4_init_once(struct nfs_inode *nfsi)
 {
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         INIT_LIST_HEAD(&nfsi->open_states);
         nfsi->delegation = NULL;
         nfsi->delegation_state = 0;
@@ -1562,6 +1571,7 @@ static void nfs_destroy_inodecache(void)
 }
 
 struct workqueue_struct *nfsiod_workqueue;
+EXPORT_SYMBOL_GPL(nfsiod_workqueue);
 
 /*
  * start up the nfsiod workqueue
@@ -1622,90 +1632,80 @@ static int __init init_nfs_fs(void)
 
         err = nfs_dns_resolver_init();
         if (err < 0)
-                goto out11;
+                goto out10;;
 
         err = register_pernet_subsys(&nfs_net_ops);
         if (err < 0)
-                goto out10;
+                goto out9;
 
         err = nfs_fscache_register();
         if (err < 0)
-                goto out9;
+                goto out8;
 
         err = nfsiod_start();
         if (err)
-                goto out8;
+                goto out7;
 
         err = nfs_fs_proc_init();
         if (err)
-                goto out7;
+                goto out6;
 
         err = nfs_init_nfspagecache();
         if (err)
-                goto out6;
+                goto out5;
 
         err = nfs_init_inodecache();
         if (err)
-                goto out5;
+                goto out4;
 
         err = nfs_init_readpagecache();
         if (err)
-                goto out4;
+                goto out3;
 
         err = nfs_init_writepagecache();
         if (err)
-                goto out3;
+                goto out2;
 
         err = nfs_init_directcache();
         if (err)
-                goto out2;
+                goto out1;
 
 #ifdef CONFIG_PROC_FS
         rpc_proc_register(&init_net, &nfs_rpcstat);
 #endif
-
-        err = nfs_register_versions();
-        if (err)
-                goto out1;
-
         if ((err = register_nfs_fs()) != 0)
                 goto out0;
 
         return 0;
 out0:
-        nfs_unregister_versions();
-out1:
 #ifdef CONFIG_PROC_FS
         rpc_proc_unregister(&init_net, "nfs");
 #endif
         nfs_destroy_directcache();
-out2:
+out1:
         nfs_destroy_writepagecache();
-out3:
+out2:
         nfs_destroy_readpagecache();
-out4:
+out3:
         nfs_destroy_inodecache();
-out5:
+out4:
         nfs_destroy_nfspagecache();
-out6:
+out5:
         nfs_fs_proc_exit();
-out7:
+out6:
         nfsiod_stop();
-out8:
+out7:
         nfs_fscache_unregister();
-out9:
+out8:
         unregister_pernet_subsys(&nfs_net_ops);
-out10:
+out9:
         nfs_dns_resolver_destroy();
-out11:
+out10:
         return err;
 }
 
 static void __exit exit_nfs_fs(void)
 {
-#ifdef CONFIG_NFS_V4
-        exit_nfs_v4();
-#endif
         nfs_destroy_directcache();
         nfs_destroy_writepagecache();
         nfs_destroy_readpagecache();
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 64f0dc41a9b7..8865538b26b6 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -262,7 +262,7 @@ extern int nfs3_decode_dirent(struct xdr_stream *,
                                 struct nfs_entry *, int);
 
 /* nfs4xdr.c */
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 extern int nfs4_decode_dirent(struct xdr_stream *,
                                 struct nfs_entry *, int);
 #endif
@@ -272,7 +272,7 @@ extern const u32 nfs41_maxwrite_overhead;
 #endif
 
 /* nfs4proc.c */
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 extern struct rpc_procinfo nfs4_procedures[];
 #endif
 
@@ -328,7 +328,7 @@ extern int nfs_wait_bit_killable(void *word);
 extern const struct super_operations nfs_sops;
 extern struct file_system_type nfs_fs_type;
 extern struct file_system_type nfs_xdev_fs_type;
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 extern struct file_system_type nfs4_xdev_fs_type;
 extern struct file_system_type nfs4_referral_fs_type;
 #endif
@@ -364,7 +364,7 @@ struct vfsmount *nfs_do_submount(struct dentry *, struct nfs_fh *,
 /* getroot.c */
 extern struct dentry *nfs_get_root(struct super_block *, struct nfs_fh *,
                                    const char *);
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 extern struct dentry *nfs4_get_root(struct super_block *, struct nfs_fh *,
                                     const char *);
 
diff --git a/fs/nfs/namespace.c b/fs/nfs/namespace.c
index 2a3b170e88e0..655925373b91 100644
--- a/fs/nfs/namespace.c
+++ b/fs/nfs/namespace.c
@@ -113,6 +113,7 @@ Elong_unlock:
 Elong:
         return ERR_PTR(-ENAMETOOLONG);
 }
+EXPORT_SYMBOL_GPL(nfs_path);
 
 /*
  * nfs_d_automount - Handle crossing a mountpoint on the server
@@ -241,6 +242,7 @@ out:
         dprintk("<-- nfs_do_submount() = %p\n", mnt);
         return mnt;
 }
+EXPORT_SYMBOL_GPL(nfs_do_submount);
 
 struct vfsmount *nfs_submount(struct nfs_server *server, struct dentry *dentry,
                               struct nfs_fh *fh, struct nfs_fattr *fattr)
diff --git a/fs/nfs/netns.h b/fs/nfs/netns.h
index 8a6394edb8b0..0539de1b8d1f 100644
--- a/fs/nfs/netns.h
+++ b/fs/nfs/netns.h
@@ -20,7 +20,7 @@ struct nfs_net {
         wait_queue_head_t bl_wq;
         struct list_head nfs_client_list;
         struct list_head nfs_volume_list;
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         struct idr cb_ident_idr; /* Protected by nfs_client_lock */
 #endif
         spinlock_t nfs_client_lock;
diff --git a/fs/nfs/nfs.h b/fs/nfs/nfs.h
index 3e1b84baa57f..43679df56cd0 100644
--- a/fs/nfs/nfs.h
+++ b/fs/nfs/nfs.h
@@ -21,23 +21,6 @@ struct nfs_subversion {
         struct list_head list;          /* List of NFS versions */
 };
 
-int nfs_register_versions(void);
-void nfs_unregister_versions(void);
-
-#ifdef CONFIG_NFS_V4
-int init_nfs_v4(void);
-void exit_nfs_v4(void);
-#else /* CONFIG_NFS_V4 */
-static inline int __init init_nfs_v4(void)
-{
-        return 0;
-}
-
-static inline void exit_nfs_v4(void)
-{
-}
-#endif /* CONFIG_NFS_V4 */
-
 struct nfs_subversion *get_nfs_version(unsigned int);
 void put_nfs_version(struct nfs_subversion *);
 void register_nfs_version(struct nfs_subversion *);
diff --git a/fs/nfs/nfs4_fs.h b/fs/nfs/nfs4_fs.h
index bafe5186c9cd..3b950dd81e81 100644
--- a/fs/nfs/nfs4_fs.h
+++ b/fs/nfs/nfs4_fs.h
@@ -9,7 +9,7 @@
 #ifndef __LINUX_FS_NFS_NFS4_FS_H
 #define __LINUX_FS_NFS_NFS4_FS_H
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 
 struct idmap;
 
@@ -365,11 +365,10 @@ extern const nfs4_stateid zero_stateid;
 struct nfs_mount_info;
 extern struct nfs_subversion nfs_v4;
 struct dentry *nfs4_try_mount(int, const char *, struct nfs_mount_info *, struct nfs_subversion *);
-int init_nfs_v4(void);
-void exit_nfs_v4(void);
 extern bool nfs4_disable_idmapping;
 extern unsigned short max_session_slots;
 extern unsigned short send_implementation_id;
+
 /* nfs4sysctl.c */
 #ifdef CONFIG_SYSCTL
 int nfs4_register_sysctl(void);
diff --git a/fs/nfs/nfs4super.c b/fs/nfs/nfs4super.c
index 1c825f3bef51..12a31a9dbcdd 100644
--- a/fs/nfs/nfs4super.c
+++ b/fs/nfs/nfs4super.c
@@ -332,7 +332,7 @@ static struct dentry *nfs4_referral_mount(struct file_system_type *fs_type,
 }
 
 
-int __init init_nfs_v4(void)
+static int __init init_nfs_v4(void)
 {
         int err;
 
@@ -358,10 +358,15 @@ out:
         return err;
 }
 
-void exit_nfs_v4(void)
+static void __exit exit_nfs_v4(void)
 {
         unregister_nfs_version(&nfs_v4);
         unregister_filesystem(&nfs4_fs_type);
         nfs4_unregister_sysctl();
         nfs_idmap_quit();
 }
+
+MODULE_LICENSE("GPL");
+
+module_init(init_nfs_v4);
+module_exit(exit_nfs_v4);
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index aed913c833f4..1e7d8879dae6 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -54,6 +54,7 @@ void nfs_pgheader_init(struct nfs_pageio_descriptor *desc,
         if (hdr->completion_ops->init_hdr)
                 hdr->completion_ops->init_hdr(hdr);
 }
+EXPORT_SYMBOL_GPL(nfs_pgheader_init);
 
 void nfs_set_pgio_error(struct nfs_pgio_header *hdr, int error, loff_t pos)
 {
@@ -268,6 +269,7 @@ void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
         desc->pg_lseg = NULL;
         desc->pg_dreq = NULL;
 }
+EXPORT_SYMBOL_GPL(nfs_pageio_init);
 
 /**
  * nfs_can_coalesce_requests - test two requests for compatibility
@@ -409,6 +411,7 @@ int nfs_pageio_add_request(struct nfs_pageio_descriptor *desc,
         } while (ret);
         return ret;
 }
+EXPORT_SYMBOL_GPL(nfs_pageio_add_request);
 
 /**
  * nfs_pageio_complete - Complete I/O on an nfs_pageio_descriptor
@@ -424,6 +427,7 @@ void nfs_pageio_complete(struct nfs_pageio_descriptor *desc)
                         break;
         }
 }
+EXPORT_SYMBOL_GPL(nfs_pageio_complete);
 
 /**
  * nfs_pageio_cond_complete - Conditional I/O completion
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 7fbd25afe418..76875bfcf19c 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -1407,6 +1407,7 @@ static void pnfs_writehdr_free(struct nfs_pgio_header *hdr)
         put_lseg(hdr->lseg);
         nfs_writehdr_free(hdr);
 }
+EXPORT_SYMBOL_GPL(pnfs_writehdr_free);
 
 int
 pnfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
@@ -1561,6 +1562,7 @@ static void pnfs_readhdr_free(struct nfs_pgio_header *hdr)
         put_lseg(hdr->lseg);
         nfs_readhdr_free(hdr);
 }
+EXPORT_SYMBOL_GPL(pnfs_readhdr_free);
 
 int
 pnfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index b000e4c0cf83..6935e401ad76 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -48,6 +48,7 @@ struct nfs_read_header *nfs_readhdr_alloc(void)
         }
         return rhdr;
 }
+EXPORT_SYMBOL_GPL(nfs_readhdr_alloc);
 
 static struct nfs_read_data *nfs_readdata_alloc(struct nfs_pgio_header *hdr,
                                                 unsigned int pagecount)
@@ -80,6 +81,7 @@ void nfs_readhdr_free(struct nfs_pgio_header *hdr)
 
         kmem_cache_free(nfs_rdata_cachep, rhdr);
 }
+EXPORT_SYMBOL_GPL(nfs_readhdr_free);
 
 void nfs_readdata_release(struct nfs_read_data *rdata)
 {
@@ -96,6 +98,7 @@ void nfs_readdata_release(struct nfs_read_data *rdata)
         if (atomic_dec_and_test(&hdr->refcnt))
                 hdr->completion_ops->completion(hdr);
 }
+EXPORT_SYMBOL_GPL(nfs_readdata_release);
 
 static
 int nfs_return_empty_page(struct page *page)
@@ -398,6 +401,7 @@ int nfs_generic_pagein(struct nfs_pageio_descriptor *desc,
                 return nfs_pagein_multi(desc, hdr);
         return nfs_pagein_one(desc, hdr);
 }
+EXPORT_SYMBOL_GPL(nfs_generic_pagein);
 
 static int nfs_generic_pg_readpages(struct nfs_pageio_descriptor *desc)
 {
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 558a85c9594a..ac6a3c55dce4 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -315,7 +315,7 @@ const struct super_operations nfs_sops = {
 };
 EXPORT_SYMBOL_GPL(nfs_sops);
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *);
 static int nfs4_validate_mount_data(void *options,
         struct nfs_parsed_mount_data *args, const char *dev_name);
@@ -366,6 +366,7 @@ void nfs_sb_active(struct super_block *sb)
         if (atomic_inc_return(&server->active) == 1)
                 atomic_inc(&sb->s_active);
 }
+EXPORT_SYMBOL_GPL(nfs_sb_active);
 
 void nfs_sb_deactive(struct super_block *sb)
 {
@@ -374,6 +375,7 @@ void nfs_sb_deactive(struct super_block *sb)
         if (atomic_dec_and_test(&server->active))
                 deactivate_super(sb);
 }
+EXPORT_SYMBOL_GPL(nfs_sb_deactive);
 
 /*
  * Deliver file system statistics to userspace
@@ -439,6 +441,7 @@ int nfs_statfs(struct dentry *dentry, struct kstatfs *buf)
         dprintk("%s: statfs error = %d\n", __func__, -error);
         return error;
 }
+EXPORT_SYMBOL_GPL(nfs_statfs);
 
 /*
  * Map the security flavour number to a name
@@ -544,7 +547,7 @@ static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss,
         nfs_show_mountd_netid(m, nfss, showdefaults);
 }
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss,
                                     int showdefaults)
 {
@@ -675,8 +678,9 @@ int nfs_show_options(struct seq_file *m, struct dentry *root)
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_show_options);
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 #ifdef CONFIG_NFS_V4_1
 static void show_sessions(struct seq_file *m, struct nfs_server *server)
 {
@@ -709,7 +713,7 @@ static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss)
         }
 }
 #else
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 static void show_pnfs(struct seq_file *m, struct nfs_server *server)
 {
 }
@@ -734,12 +738,14 @@ int nfs_show_devname(struct seq_file *m, struct dentry *root)
         free_page((unsigned long)page);
         return err;
 }
+EXPORT_SYMBOL_GPL(nfs_show_devname);
 
 int nfs_show_path(struct seq_file *m, struct dentry *dentry)
 {
         seq_puts(m, "/");
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_show_path);
 
 /*
  * Present statistical information for this VFS mountpoint
@@ -774,7 +780,7 @@ int nfs_show_stats(struct seq_file *m, struct dentry *root)
         seq_printf(m, ",bsize=%u", nfss->bsize);
         seq_printf(m, ",namlen=%u", nfss->namelen);
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         if (nfss->nfs_client->rpc_ops->version == 4) {
                 seq_printf(m, "\n\tnfsv4:\t");
                 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]);
@@ -832,6 +838,7 @@ int nfs_show_stats(struct seq_file *m, struct dentry *root)
 
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_show_stats);
 
 /*
  * Begin unmount by attempting to remove all automounted mountpoints we added
@@ -851,6 +858,7 @@ void nfs_umount_begin(struct super_block *sb)
         if (!IS_ERR(rpc))
                 rpc_killall_tasks(rpc);
 }
+EXPORT_SYMBOL_GPL(nfs_umount_begin);
 
 static struct nfs_parsed_mount_data *nfs_alloc_parsed_mount_data(void)
 {
@@ -1915,7 +1923,7 @@ out_invalid_fh:
         return -EINVAL;
 }
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 static int nfs_validate_mount_data(struct file_system_type *fs_type,
                                    void *options,
                                    struct nfs_parsed_mount_data *args,
@@ -1953,7 +1961,7 @@ static int nfs_validate_text_mount_data(void *options,
                 goto out_no_address;
 
         if (args->version == 4) {
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
                 port = NFS_PORT;
                 max_namelen = NFS4_MAXNAMLEN;
                 max_pathlen = NFS4_MAXPATHLEN;
@@ -1976,7 +1984,7 @@ static int nfs_validate_text_mount_data(void *options,
                                    &args->nfs_server.export_path,
                                    max_pathlen);
 
-#ifndef CONFIG_NFS_V4
+#if !IS_ENABLED(CONFIG_NFS_V4)
 out_v4_not_compiled:
         dfprintk(MOUNT, "NFS: NFSv4 is not compiled into kernel\n");
         return -EPROTONOSUPPORT;
@@ -2075,6 +2083,7 @@ out:
         kfree(data);
         return error;
 }
+EXPORT_SYMBOL_GPL(nfs_remount);
 
 /*
  * Initialise the common bits of the superblock
@@ -2123,6 +2132,7 @@ void nfs_fill_super(struct super_block *sb, struct nfs_mount_info *mount_info)
 
         nfs_initialise_sb(sb);
 }
+EXPORT_SYMBOL_GPL(nfs_fill_super);
 
 /*
  * Finish setting up a cloned NFS2/3/4 superblock
@@ -2292,6 +2302,7 @@ int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot,
 {
         return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts);
 }
+EXPORT_SYMBOL_GPL(nfs_set_sb_security);
 
 int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
                           struct nfs_mount_info *mount_info)
@@ -2302,6 +2313,7 @@ int nfs_clone_sb_security(struct super_block *s, struct dentry *mntroot,
                 return -ESTALE;
         return 0;
 }
+EXPORT_SYMBOL_GPL(nfs_clone_sb_security);
 
 struct dentry *nfs_fs_mount_common(struct nfs_server *server,
                                    int flags, const char *dev_name,
@@ -2375,6 +2387,7 @@ error_splat_bdi:
         deactivate_locked_super(s);
         goto out;
 }
+EXPORT_SYMBOL_GPL(nfs_fs_mount_common);
 
 struct dentry *nfs_fs_mount(struct file_system_type *fs_type,
         int flags, const char *dev_name, void *raw_data)
@@ -2415,6 +2428,7 @@ out:
         nfs_free_fhandle(mount_info.mntfh);
         return mntroot;
 }
+EXPORT_SYMBOL_GPL(nfs_fs_mount);
 
 /*
  * Ensure that we unregister the bdi before kill_anon_super
@@ -2426,6 +2440,7 @@ void nfs_put_super(struct super_block *s)
 
         bdi_unregister(&server->backing_dev_info);
 }
+EXPORT_SYMBOL_GPL(nfs_put_super);
 
 /*
  * Destroy an NFS2/3 superblock
@@ -2438,6 +2453,7 @@ void nfs_kill_super(struct super_block *s)
         nfs_fscache_release_super_cookie(s);
         nfs_free_server(server);
 }
+EXPORT_SYMBOL_GPL(nfs_kill_super);
 
 /*
  * Clone an NFS2/3/4 server record on xdev traversal (FSID-change)
@@ -2478,7 +2494,7 @@ out_err:
         goto out;
 }
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 
 static void nfs4_validate_mount_flags(struct nfs_parsed_mount_data *args)
 {
@@ -2590,6 +2606,13 @@ bool nfs4_disable_idmapping = true;
 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE;
 unsigned short send_implementation_id = 1;
 
+EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport);
+EXPORT_SYMBOL_GPL(nfs_callback_tcpport);
+EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout);
+EXPORT_SYMBOL_GPL(nfs4_disable_idmapping);
+EXPORT_SYMBOL_GPL(max_session_slots);
+EXPORT_SYMBOL_GPL(send_implementation_id);
+
 #define NFS_CALLBACK_MAXPORTNR (65535U)
 
 static int param_set_portnr(const char *val, const struct kernel_param *kp)
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index f268fe4f2785..e4a2ad2059bd 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -84,6 +84,7 @@ struct nfs_write_header *nfs_writehdr_alloc(void)
         }
         return p;
 }
+EXPORT_SYMBOL_GPL(nfs_writehdr_alloc);
 
 static struct nfs_write_data *nfs_writedata_alloc(struct nfs_pgio_header *hdr,
                                                   unsigned int pagecount)
@@ -115,6 +116,7 @@ void nfs_writehdr_free(struct nfs_pgio_header *hdr)
         struct nfs_write_header *whdr = container_of(hdr, struct nfs_write_header, header);
         mempool_free(whdr, nfs_wdata_mempool);
 }
+EXPORT_SYMBOL_GPL(nfs_writehdr_free);
 
 void nfs_writedata_release(struct nfs_write_data *wdata)
 {
@@ -131,6 +133,7 @@ void nfs_writedata_release(struct nfs_write_data *wdata)
         if (atomic_dec_and_test(&hdr->refcnt))
                 hdr->completion_ops->completion(hdr);
 }
+EXPORT_SYMBOL_GPL(nfs_writedata_release);
 
 static void nfs_context_set_write_error(struct nfs_open_context *ctx, int error)
 {
@@ -446,7 +449,7 @@ nfs_mark_request_dirty(struct nfs_page *req)
         __set_page_dirty_nobuffers(req->wb_page);
 }
 
-#if IS_ENABLED(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
 /**
  * nfs_request_add_commit_list - add request to a commit list
  * @req: pointer to a struct nfs_page
@@ -636,7 +639,7 @@ out:
         hdr->release(hdr);
 }
 
-#if  IS_ENABLED(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
+#if  IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
 static unsigned long
 nfs_reqs_to_commit(struct nfs_commit_info *cinfo)
 {
@@ -1173,6 +1176,7 @@ int nfs_generic_flush(struct nfs_pageio_descriptor *desc,
                 return nfs_flush_multi(desc, hdr);
         return nfs_flush_one(desc, hdr);
 }
+EXPORT_SYMBOL_GPL(nfs_generic_flush);
 
 static int nfs_generic_pg_writepages(struct nfs_pageio_descriptor *desc)
 {
@@ -1298,7 +1302,7 @@ void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data)
                 return;
         nfs_add_stats(inode, NFSIOS_SERVERWRITTENBYTES, resp->count);
 
-#if IS_ENABLED(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
         if (resp->verf->committed < argp->stable && task->tk_status >= 0) {
                 /* We tried a write call, but the server did not
                  * commit data to stable storage even though we
@@ -1358,7 +1362,7 @@ void nfs_writeback_done(struct rpc_task *task, struct nfs_write_data *data)
 }
 
 
-#if IS_ENABLED(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
 static int nfs_commit_set_lock(struct nfs_inode *nfsi, int may_wait)
 {
         int ret;
@@ -1674,6 +1678,7 @@ int nfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 {
         return nfs_commit_unstable_pages(inode, wbc);
 }
+EXPORT_SYMBOL_GPL(nfs_write_inode);
 
 /*
  * flush the inode to disk.
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 4b6043c20f77..2889877318bc 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -191,7 +191,7 @@ struct nfs_inode {
         struct hlist_head       silly_list;
         wait_queue_head_t       waitqueue;
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         struct nfs4_cached_acl  *nfs4_acl;
         /* NFSv4 state */
         struct list_head        open_states;
@@ -428,7 +428,7 @@ extern __be32 root_nfs_parse_addr(char *name); /*__init*/
  * linux/fs/nfs/file.c
  */
 extern const struct file_operations nfs_file_operations;
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 extern const struct file_operations nfs4_file_operations;
 #endif /* CONFIG_NFS_V4 */
 extern const struct address_space_operations nfs_file_aops;
@@ -538,7 +538,7 @@ extern void nfs_writeback_done(struct rpc_task *, struct nfs_write_data *);
 extern int nfs_wb_all(struct inode *inode);
 extern int nfs_wb_page(struct inode *inode, struct page* page);
 extern int nfs_wb_page_cancel(struct inode *inode, struct page* page);
-#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V3) || IS_ENABLED(CONFIG_NFS_V4)
 extern int  nfs_commit_inode(struct inode *, int);
 extern struct nfs_commit_data *nfs_commitdata_alloc(void);
 extern void nfs_commit_free(struct nfs_commit_data *data);
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 6039297801f4..310c63c8ab2c 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -53,7 +53,7 @@ struct nfs_client {
         u32                     cl_minorversion;/* NFSv4 minorversion */
         struct rpc_cred         *cl_machine_cred;
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         u64                     cl_clientid;    /* constant */
         nfs4_verifier           cl_confirm;     /* Clientid verifier */
         unsigned long           cl_state;
@@ -138,7 +138,7 @@ struct nfs_server {
 #endif
 
         u32                     pnfs_blksize;   /* layout_blksize attr */
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
         u32                     attr_bitmask[3];/* V4 bitmask representing the set
                                                    of attributes supported on this
                                                    filesystem */
@@ -201,7 +201,7 @@ struct nfs_server {
 #define NFS4_MAX_SLOT_TABLE (256U)
 #define NFS4_NO_SLOT ((u32)-1)
 
-#if defined(CONFIG_NFS_V4)
+#if IS_ENABLED(CONFIG_NFS_V4)
 
 /* Sessions */
 #define SLOT_TABLE_SZ DIV_ROUND_UP(NFS4_MAX_SLOT_TABLE, 8*sizeof(long))
diff --git a/include/linux/nfs_idmap.h b/include/linux/nfs_idmap.h
index 7eed2012d288..ece91c57ad79 100644
--- a/include/linux/nfs_idmap.h
+++ b/include/linux/nfs_idmap.h
@@ -69,7 +69,7 @@ struct nfs_server;
 struct nfs_fattr;
 struct nfs4_string;
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 int nfs_idmap_init(void);
 void nfs_idmap_quit(void);
 #else
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index 631182062994..00485e084394 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -824,7 +824,7 @@ struct nfs3_getaclres {
         struct posix_acl *      acl_default;
 };
 
-#ifdef CONFIG_NFS_V4
+#if IS_ENABLED(CONFIG_NFS_V4)
 
 typedef u64 clientid4;