1 // SPDX-License-Identifier: LGPL-2.1 2 /* 3 * 4 * Copyright (C) International Business Machines Corp., 2007 5 * Author(s): Steve French (sfrench@us.ibm.com) 6 * 7 * Common Internet FileSystem (CIFS) client 8 * 9 * Operations related to support for exporting files via NFSD 10 * 11 */ 12 13 /* 14 * See Documentation/filesystems/nfs/exporting.rst 15 * and examples in fs/exportfs 16 * 17 * Since cifs is a network file system, an "fsid" must be included for 18 * any nfs exports file entries which refer to cifs paths. In addition 19 * the cifs mount must be mounted with the "serverino" option (ie use stable 20 * server inode numbers instead of locally generated temporary ones). 21 * Although cifs inodes do not use generation numbers (have generation number 22 * of zero) - the inode number alone should be good enough for simple cases 23 * in which users want to export cifs shares with NFS. The decode and encode 24 * could be improved by using a new routine which expects 64 bit inode numbers 25 * instead of the default 32 bit routines in fs/exportfs 26 * 27 */ 28 29 #include <linux/fs.h> 30 #include <linux/exportfs.h> 31 #include "cifsglob.h" 32 #include "cifs_debug.h" 33 #include "cifsfs.h" 34 35 #ifdef CONFIG_CIFS_NFSD_EXPORT 36 static struct dentry *cifs_get_parent(struct dentry *dentry) 37 { 38 /* BB need to add code here eventually to enable export via NFSD */ 39 cifs_dbg(FYI, "get parent for %p\n", dentry); 40 return ERR_PTR(-EACCES); 41 } 42 43 const struct export_operations cifs_export_ops = { 44 .get_parent = cifs_get_parent, 45 /* Following five export operations are unneeded so far and can default: 46 .get_dentry = 47 .get_name = 48 .find_exported_dentry = 49 .decode_fh = 50 .encode_fs = */ 51 }; 52 53 #endif /* CONFIG_CIFS_NFSD_EXPORT */ 54 55