4 files changed, 16 insertions, 8 deletions

diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index 4b6043c20f7..2889877318b 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 65327652c61..310c63c8ab2 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -48,11 +48,12 @@ struct nfs_client {
 	struct rpc_clnt *	cl_rpcclient;
 	const struct nfs_rpc_ops *rpc_ops;	/* NFS protocol vector */
 	int			cl_proto;	/* Network transport protocol */
+	struct nfs_subversion *	cl_nfs_mod;	/* pointer to nfs version module */
 
 	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;
@@ -137,7 +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 */
@@ -200,7 +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 7eed2012d28..ece91c57ad7 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 0e181c2320b..00485e08439 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;
 
@@ -1353,6 +1353,8 @@ struct nfs_renamedata {
 struct nfs_access_entry;
 struct nfs_client;
 struct rpc_timeout;
+struct nfs_subversion;
+struct nfs_mount_info;
 struct nfs_client_initdata;
 struct nfs_pageio_descriptor;
 
@@ -1370,6 +1372,8 @@ struct nfs_rpc_ops {
 			    struct nfs_fsinfo *);
 	struct vfsmount *(*submount) (struct nfs_server *, struct dentry *,
 				      struct nfs_fh *, struct nfs_fattr *);
+	struct dentry *(*try_mount) (int, const char *, struct nfs_mount_info *,
+				     struct nfs_subversion *);
 	int	(*getattr) (struct nfs_server *, struct nfs_fh *,
 			    struct nfs_fattr *);
 	int	(*setattr) (struct dentry *, struct nfs_fattr *,
@@ -1435,6 +1439,9 @@ struct nfs_rpc_ops {
 		(*init_client) (struct nfs_client *, const struct rpc_timeout *,
 				const char *, rpc_authflavor_t);
 	void	(*free_client) (struct nfs_client *);
+	struct nfs_server *(*create_server)(struct nfs_mount_info *, struct nfs_subversion *);
+	struct nfs_server *(*clone_server)(struct nfs_server *, struct nfs_fh *,
+					   struct nfs_fattr *, rpc_authflavor_t);
 };
 
 /*