NFS: Clean up the (commit|read|write)_setup() callback routines

Move the common code for setting up the nfs_write_data and nfs_read_data
structures into fs/nfs/read.c, fs/nfs/write.c and fs/nfs/direct.c.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h
index daab252..6b213a6 100644
--- a/include/linux/nfs_xdr.h
+++ b/include/linux/nfs_xdr.h
@@ -816,11 +816,11 @@
 			     struct nfs_pathconf *);
 	int	(*set_capabilities)(struct nfs_server *, struct nfs_fh *);
 	__be32 *(*decode_dirent)(__be32 *, struct nfs_entry *, int plus);
-	void	(*read_setup)   (struct nfs_read_data *);
+	void	(*read_setup)   (struct nfs_read_data *, struct rpc_message *);
 	int	(*read_done)  (struct rpc_task *, struct nfs_read_data *);
-	void	(*write_setup)  (struct nfs_write_data *, int how);
+	void	(*write_setup)  (struct nfs_write_data *, struct rpc_message *);
 	int	(*write_done)  (struct rpc_task *, struct nfs_write_data *);
-	void	(*commit_setup) (struct nfs_write_data *, int how);
+	void	(*commit_setup) (struct nfs_write_data *, struct rpc_message *);
 	int	(*commit_done) (struct rpc_task *, struct nfs_write_data *);
 	int	(*file_open)   (struct inode *, struct file *);
 	int	(*file_release) (struct inode *, struct file *);