/*
 *  fs/nfs/nfs4xdr.c
 *
 *  Client-side XDR for NFSv4.
 *
 *  Copyright (c) 2002 The Regents of the University of Michigan.
 *  All rights reserved.
 *
 *  Kendrick Smith <kmsmith@umich.edu>
 *  Andy Adamson   <andros@umich.edu>
 * 
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  3. Neither the name of the University nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
 *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <linux/param.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/utsname.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/pagemap.h>
#include <linux/proc_fs.h>
#include <linux/kdev_t.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs.h>
#include <linux/nfs4.h>
#include <linux/nfs_fs.h>
#include <linux/nfs_idmap.h>
#include "nfs4_fs.h"

#define NFSDBG_FACILITY         NFSDBG_XDR

/* Mapping from NFS error code to "errno" error code. */
#define errno_NFSERR_IO         EIO

static int nfs4_stat_to_errno(int);

/* NFSv4 COMPOUND tags are only wanted for debugging purposes */
#ifdef DEBUG
#define NFS4_MAXTAGLEN          20
#else
#define NFS4_MAXTAGLEN          0
#endif

/* lock,open owner id: 
 * we currently use size 2 (u64) out of (NFS4_OPAQUE_LIMIT  >> 2)
 */
#define open_owner_id_maxsz     (1 + 4)
#define lock_owner_id_maxsz     (1 + 4)
#define decode_lockowner_maxsz  (1 + XDR_QUADLEN(IDMAP_NAMESZ))
#define compound_encode_hdr_maxsz       (3 + (NFS4_MAXTAGLEN >> 2))
#define compound_decode_hdr_maxsz       (3 + (NFS4_MAXTAGLEN >> 2))
#define op_encode_hdr_maxsz     (1)
#define op_decode_hdr_maxsz     (2)
#define encode_stateid_maxsz    (XDR_QUADLEN(NFS4_STATEID_SIZE))
#define decode_stateid_maxsz    (XDR_QUADLEN(NFS4_STATEID_SIZE))
#define encode_verifier_maxsz   (XDR_QUADLEN(NFS4_VERIFIER_SIZE))
#define decode_verifier_maxsz   (XDR_QUADLEN(NFS4_VERIFIER_SIZE))
#define encode_putfh_maxsz      (op_encode_hdr_maxsz + 1 + \
                                (NFS4_FHSIZE >> 2))
#define decode_putfh_maxsz      (op_decode_hdr_maxsz)
#define encode_putrootfh_maxsz  (op_encode_hdr_maxsz)
#define decode_putrootfh_maxsz  (op_decode_hdr_maxsz)
#define encode_getfh_maxsz      (op_encode_hdr_maxsz)
#define decode_getfh_maxsz      (op_decode_hdr_maxsz + 1 + \
                                ((3+NFS4_FHSIZE) >> 2))
#define nfs4_fattr_bitmap_maxsz 3
#define encode_getattr_maxsz    (op_encode_hdr_maxsz + nfs4_fattr_bitmap_maxsz)
#define nfs4_name_maxsz         (1 + ((3 + NFS4_MAXNAMLEN) >> 2))
#define nfs4_path_maxsz         (1 + ((3 + NFS4_MAXPATHLEN) >> 2))
#define nfs4_owner_maxsz        (1 + XDR_QUADLEN(IDMAP_NAMESZ))
#define nfs4_group_maxsz        (1 + XDR_QUADLEN(IDMAP_NAMESZ))
/* This is based on getfattr, which uses the most attributes: */
#define nfs4_fattr_value_maxsz  (1 + (1 + 2 + 2 + 4 + 2 + 1 + 1 + 2 + 2 + \
                                3 + 3 + 3 + nfs4_owner_maxsz + nfs4_group_maxsz))
#define nfs4_fattr_maxsz        (nfs4_fattr_bitmap_maxsz + \
                                nfs4_fattr_value_maxsz)
#define decode_getattr_maxsz    (op_decode_hdr_maxsz + nfs4_fattr_maxsz)
#define encode_attrs_maxsz      (nfs4_fattr_bitmap_maxsz + \
                                 1 + 2 + 1 + \
                                nfs4_owner_maxsz + \
                                nfs4_group_maxsz + \
                                4 + 4)
#define encode_savefh_maxsz     (op_encode_hdr_maxsz)
#define decode_savefh_maxsz     (op_decode_hdr_maxsz)
#define encode_restorefh_maxsz  (op_encode_hdr_maxsz)
#define decode_restorefh_maxsz  (op_decode_hdr_maxsz)
#define encode_fsinfo_maxsz     (encode_getattr_maxsz)
#define decode_fsinfo_maxsz     (op_decode_hdr_maxsz + 11)
#define encode_renew_maxsz      (op_encode_hdr_maxsz + 3)
#define decode_renew_maxsz      (op_decode_hdr_maxsz)
#define encode_setclientid_maxsz \
                                (op_encode_hdr_maxsz + \
                                XDR_QUADLEN(NFS4_VERIFIER_SIZE) + \
                                XDR_QUADLEN(NFS4_SETCLIENTID_NAMELEN) + \
                                1 /* sc_prog */ + \
                                XDR_QUADLEN(RPCBIND_MAXNETIDLEN) + \
                                XDR_QUADLEN(RPCBIND_MAXUADDRLEN) + \
                                1) /* sc_cb_ident */
#define decode_setclientid_maxsz \
                                (op_decode_hdr_maxsz + \
                                2 + \
                                1024) /* large value for CLID_INUSE */
#define encode_setclientid_confirm_maxsz \
                                (op_encode_hdr_maxsz + \
                                3 + (NFS4_VERIFIER_SIZE >> 2))
#define decode_setclientid_confirm_maxsz \
                                (op_decode_hdr_maxsz)
#define encode_lookup_maxsz     (op_encode_hdr_maxsz + nfs4_name_maxsz)
#define decode_lookup_maxsz     (op_decode_hdr_maxsz)
#define encode_share_access_maxsz \
                                (2)
#define encode_createmode_maxsz (1 + encode_attrs_maxsz)
#define encode_opentype_maxsz   (1 + encode_createmode_maxsz)
#define encode_claim_null_maxsz (1 + nfs4_name_maxsz)
#define encode_open_maxsz       (op_encode_hdr_maxsz + \
                                2 + encode_share_access_maxsz + 2 + \
                                open_owner_id_maxsz + \
                                encode_opentype_maxsz + \
                                encode_claim_null_maxsz)
#define decode_ace_maxsz        (3 + nfs4_owner_maxsz)
#define decode_delegation_maxsz (1 + decode_stateid_maxsz + 1 + \
                                decode_ace_maxsz)
#define decode_change_info_maxsz        (5)
#define decode_open_maxsz       (op_decode_hdr_maxsz + \
                                decode_stateid_maxsz + \
                                decode_change_info_maxsz + 1 + \
                                nfs4_fattr_bitmap_maxsz + \
                                decode_delegation_maxsz)
#define encode_open_confirm_maxsz \
                                (op_encode_hdr_maxsz + \
                                 encode_stateid_maxsz + 1)
#define decode_open_confirm_maxsz \
                                (op_decode_hdr_maxsz + \
                                 decode_stateid_maxsz)
#define encode_open_downgrade_maxsz \
                                (op_encode_hdr_maxsz + \
                                 encode_stateid_maxsz + 1 + \
                                 encode_share_access_maxsz)
#define decode_open_downgrade_maxsz \
                                (op_decode_hdr_maxsz + \
                                 decode_stateid_maxsz)
#define encode_close_maxsz      (op_encode_hdr_maxsz + \
                                 1 + encode_stateid_maxsz)
#define decode_close_maxsz      (op_decode_hdr_maxsz + \
                                 decode_stateid_maxsz)
#define encode_setattr_maxsz    (op_encode_hdr_maxsz + \
                                 encode_stateid_maxsz + \
                                 encode_attrs_maxsz)
#define decode_setattr_maxsz    (op_decode_hdr_maxsz + \
                                 nfs4_fattr_bitmap_maxsz)
#define encode_read_maxsz       (op_encode_hdr_maxsz + \
                                 encode_stateid_maxsz + 3)
#define decode_read_maxsz       (op_decode_hdr_maxsz + 2)
#define encode_readdir_maxsz    (op_encode_hdr_maxsz + \
                                 2 + encode_verifier_maxsz + 5)
#define decode_readdir_maxsz    (op_decode_hdr_maxsz + \
                                 decode_verifier_maxsz)
#define encode_readlink_maxsz   (op_encode_hdr_maxsz)
#define decode_readlink_maxsz   (op_decode_hdr_maxsz + 1)
#define encode_write_maxsz      (op_encode_hdr_maxsz + \
                                 encode_stateid_maxsz + 4)
#define decode_write_maxsz      (op_decode_hdr_maxsz + \
                                 2 + decode_verifier_maxsz)
#define encode_commit_maxsz     (op_encode_hdr_maxsz + 3)
#define decode_commit_maxsz     (op_decode_hdr_maxsz + \
                                 decode_verifier_maxsz)
#define encode_remove_maxsz     (op_encode_hdr_maxsz + \
                                nfs4_name_maxsz)
#define encode_rename_maxsz     (op_encode_hdr_maxsz + \
                                2 * nfs4_name_maxsz)
#define decode_rename_maxsz     (op_decode_hdr_maxsz + 5 + 5)
#define encode_link_maxsz       (op_encode_hdr_maxsz + \
                                nfs4_name_maxsz)
#define decode_link_maxsz       (op_decode_hdr_maxsz + 5)
#define encode_lock_maxsz       (op_encode_hdr_maxsz + \
                                 7 + \
                                 1 + encode_stateid_maxsz + 8)
#define decode_lock_denied_maxsz \
                                (8 + decode_lockowner_maxsz)
#define decode_lock_maxsz       (op_decode_hdr_maxsz + \
                                 decode_lock_denied_maxsz)
#define encode_lockt_maxsz      (op_encode_hdr_maxsz + 12)
#define decode_lockt_maxsz      (op_decode_hdr_maxsz + \
                                 decode_lock_denied_maxsz)
#define encode_locku_maxsz      (op_encode_hdr_maxsz + 3 + \
                                 encode_stateid_maxsz + \
                                 4)
#define decode_locku_maxsz      (op_decode_hdr_maxsz + \
                                 decode_stateid_maxsz)
#define encode_access_maxsz     (op_encode_hdr_maxsz + 1)
#define decode_access_maxsz     (op_decode_hdr_maxsz + 2)
#define encode_symlink_maxsz    (op_encode_hdr_maxsz + \
                                1 + nfs4_name_maxsz + \
                                1 + \
                                nfs4_fattr_maxsz)
#define decode_symlink_maxsz    (op_decode_hdr_maxsz + 8)
#define encode_create_maxsz     (op_encode_hdr_maxsz + \
                                1 + 2 + nfs4_name_maxsz + \
                                encode_attrs_maxsz)
#define decode_create_maxsz     (op_decode_hdr_maxsz + \
                                decode_change_info_maxsz + \
                                nfs4_fattr_bitmap_maxsz)
#define encode_statfs_maxsz     (encode_getattr_maxsz)
#define decode_statfs_maxsz     (decode_getattr_maxsz)
#define encode_delegreturn_maxsz (op_encode_hdr_maxsz + 4)
#define decode_delegreturn_maxsz (op_decode_hdr_maxsz)
#define encode_getacl_maxsz     (encode_getattr_maxsz)
#define decode_getacl_maxsz     (op_decode_hdr_maxsz + \
                                 nfs4_fattr_bitmap_maxsz + 1)
#define encode_setacl_maxsz     (op_encode_hdr_maxsz + \
                                 encode_stateid_maxsz + 3)
#define decode_setacl_maxsz     (decode_setattr_maxsz)
#define encode_fs_locations_maxsz \
                                (encode_getattr_maxsz)
#define decode_fs_locations_maxsz \
                                (0)
#define NFS4_enc_compound_sz    (1024)  /* XXX: large enough? */
#define NFS4_dec_compound_sz    (1024)  /* XXX: large enough? */
#define NFS4_enc_read_sz        (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_read_maxsz)
#define NFS4_dec_read_sz        (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_read_maxsz)
#define NFS4_enc_readlink_sz    (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_readlink_maxsz)
#define NFS4_dec_readlink_sz    (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_readlink_maxsz)
#define NFS4_enc_readdir_sz     (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_readdir_maxsz)
#define NFS4_dec_readdir_sz     (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_readdir_maxsz)
#define NFS4_enc_write_sz       (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_write_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_write_sz       (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_write_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_commit_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_commit_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_commit_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_commit_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_open_sz        (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_savefh_maxsz + \
                                encode_open_maxsz + \
                                encode_getfh_maxsz + \
                                encode_getattr_maxsz + \
                                encode_restorefh_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_open_sz        (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_savefh_maxsz + \
                                decode_open_maxsz + \
                                decode_getfh_maxsz + \
                                decode_getattr_maxsz + \
                                decode_restorefh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_open_confirm_sz \
                                (compound_encode_hdr_maxsz + \
                                 encode_putfh_maxsz + \
                                 encode_open_confirm_maxsz)
#define NFS4_dec_open_confirm_sz \
                                (compound_decode_hdr_maxsz + \
                                 decode_putfh_maxsz + \
                                 decode_open_confirm_maxsz)
#define NFS4_enc_open_noattr_sz (compound_encode_hdr_maxsz + \
                                        encode_putfh_maxsz + \
                                        encode_open_maxsz + \
                                        encode_getattr_maxsz)
#define NFS4_dec_open_noattr_sz (compound_decode_hdr_maxsz + \
                                        decode_putfh_maxsz + \
                                        decode_open_maxsz + \
                                        decode_getattr_maxsz)
#define NFS4_enc_open_downgrade_sz \
                                (compound_encode_hdr_maxsz + \
                                 encode_putfh_maxsz + \
                                 encode_open_downgrade_maxsz + \
                                 encode_getattr_maxsz)
#define NFS4_dec_open_downgrade_sz \
                                (compound_decode_hdr_maxsz + \
                                 decode_putfh_maxsz + \
                                 decode_open_downgrade_maxsz + \
                                 decode_getattr_maxsz)
#define NFS4_enc_close_sz       (compound_encode_hdr_maxsz + \
                                 encode_putfh_maxsz + \
                                 encode_close_maxsz + \
                                 encode_getattr_maxsz)
#define NFS4_dec_close_sz       (compound_decode_hdr_maxsz + \
                                 decode_putfh_maxsz + \
                                 decode_close_maxsz + \
                                 decode_getattr_maxsz)
#define NFS4_enc_setattr_sz     (compound_encode_hdr_maxsz + \
                                 encode_putfh_maxsz + \
                                 encode_setattr_maxsz + \
                                 encode_getattr_maxsz)
#define NFS4_dec_setattr_sz     (compound_decode_hdr_maxsz + \
                                 decode_putfh_maxsz + \
                                 decode_setattr_maxsz + \
                                 decode_getattr_maxsz)
#define NFS4_enc_fsinfo_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_fsinfo_maxsz)
#define NFS4_dec_fsinfo_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_fsinfo_maxsz)
#define NFS4_enc_renew_sz       (compound_encode_hdr_maxsz + \
                                encode_renew_maxsz)
#define NFS4_dec_renew_sz       (compound_decode_hdr_maxsz + \
                                decode_renew_maxsz)
#define NFS4_enc_setclientid_sz (compound_encode_hdr_maxsz + \
                                encode_setclientid_maxsz)
#define NFS4_dec_setclientid_sz (compound_decode_hdr_maxsz + \
                                decode_setclientid_maxsz)
#define NFS4_enc_setclientid_confirm_sz \
                                (compound_encode_hdr_maxsz + \
                                encode_setclientid_confirm_maxsz + \
                                encode_putrootfh_maxsz + \
                                encode_fsinfo_maxsz)
#define NFS4_dec_setclientid_confirm_sz \
                                (compound_decode_hdr_maxsz + \
                                decode_setclientid_confirm_maxsz + \
                                decode_putrootfh_maxsz + \
                                decode_fsinfo_maxsz)
#define NFS4_enc_lock_sz        (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_lock_maxsz)
#define NFS4_dec_lock_sz        (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_lock_maxsz)
#define NFS4_enc_lockt_sz       (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_lockt_maxsz)
#define NFS4_dec_lockt_sz       (compound_decode_hdr_maxsz + \
                                 decode_putfh_maxsz + \
                                 decode_lockt_maxsz)
#define NFS4_enc_locku_sz       (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_locku_maxsz)
#define NFS4_dec_locku_sz       (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_locku_maxsz)
#define NFS4_enc_access_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_access_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_access_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_access_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_getattr_sz     (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_getattr_sz     (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_lookup_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_lookup_maxsz + \
                                encode_getattr_maxsz + \
                                encode_getfh_maxsz)
#define NFS4_dec_lookup_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_lookup_maxsz + \
                                decode_getattr_maxsz + \
                                decode_getfh_maxsz)
#define NFS4_enc_lookup_root_sz (compound_encode_hdr_maxsz + \
                                encode_putrootfh_maxsz + \
                                encode_getattr_maxsz + \
                                encode_getfh_maxsz)
#define NFS4_dec_lookup_root_sz (compound_decode_hdr_maxsz + \
                                decode_putrootfh_maxsz + \
                                decode_getattr_maxsz + \
                                decode_getfh_maxsz)
#define NFS4_enc_remove_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_remove_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_remove_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                op_decode_hdr_maxsz + 5 + \
                                decode_getattr_maxsz)
#define NFS4_enc_rename_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_savefh_maxsz + \
                                encode_putfh_maxsz + \
                                encode_rename_maxsz + \
                                encode_getattr_maxsz + \
                                encode_restorefh_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_rename_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_savefh_maxsz + \
                                decode_putfh_maxsz + \
                                decode_rename_maxsz + \
                                decode_getattr_maxsz + \
                                decode_restorefh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_link_sz        (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_savefh_maxsz + \
                                encode_putfh_maxsz + \
                                encode_link_maxsz + \
                                decode_getattr_maxsz + \
                                encode_restorefh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_dec_link_sz        (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_savefh_maxsz + \
                                decode_putfh_maxsz + \
                                decode_link_maxsz + \
                                decode_getattr_maxsz + \
                                decode_restorefh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_symlink_sz     (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_symlink_maxsz + \
                                encode_getattr_maxsz + \
                                encode_getfh_maxsz)
#define NFS4_dec_symlink_sz     (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_symlink_maxsz + \
                                decode_getattr_maxsz + \
                                decode_getfh_maxsz)
#define NFS4_enc_create_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_savefh_maxsz + \
                                encode_create_maxsz + \
                                encode_getfh_maxsz + \
                                encode_getattr_maxsz + \
                                encode_restorefh_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_create_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_savefh_maxsz + \
                                decode_create_maxsz + \
                                decode_getfh_maxsz + \
                                decode_getattr_maxsz + \
                                decode_restorefh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_pathconf_sz    (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_pathconf_sz    (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_statfs_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_statfs_maxsz)
#define NFS4_dec_statfs_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_statfs_maxsz)
#define NFS4_enc_server_caps_sz (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_server_caps_sz (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_delegreturn_sz (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_delegreturn_maxsz + \
                                encode_getattr_maxsz)
#define NFS4_dec_delegreturn_sz (compound_decode_hdr_maxsz + \
                                decode_delegreturn_maxsz + \
                                decode_getattr_maxsz)
#define NFS4_enc_getacl_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_getacl_maxsz)
#define NFS4_dec_getacl_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_getacl_maxsz)
#define NFS4_enc_setacl_sz      (compound_encode_hdr_maxsz + \
                                encode_putfh_maxsz + \
                                encode_setacl_maxsz)
#define NFS4_dec_setacl_sz      (compound_decode_hdr_maxsz + \
                                decode_putfh_maxsz + \
                                decode_setacl_maxsz)
#define NFS4_enc_fs_locations_sz \
                                (compound_encode_hdr_maxsz + \
                                 encode_putfh_maxsz + \
                                 encode_lookup_maxsz + \
                                 encode_fs_locations_maxsz)
#define NFS4_dec_fs_locations_sz \
                                (compound_decode_hdr_maxsz + \
                                 decode_putfh_maxsz + \
                                 decode_lookup_maxsz + \
                                 decode_fs_locations_maxsz)

static struct {
        unsigned int    mode;
        unsigned int    nfs2type;
} nfs_type2fmt[] = {
        { 0,            NFNON        },
        { S_IFREG,      NFREG        },
        { S_IFDIR,      NFDIR        },
        { S_IFBLK,      NFBLK        },
        { S_IFCHR,      NFCHR        },
        { S_IFLNK,      NFLNK        },
        { S_IFSOCK,     NFSOCK       },
        { S_IFIFO,      NFFIFO       },
        { 0,            NFNON        },
        { 0,            NFNON        },
};

struct compound_hdr {
        int32_t         status;
        uint32_t        nops;
        uint32_t        taglen;
        char *          tag;
};

/*
 * START OF "GENERIC" ENCODE ROUTINES.
 *   These may look a little ugly since they are imported from a "generic"
 * set of XDR encode/decode routines which are intended to be shared by
 * all of our NFSv4 implementations (OpenBSD, MacOS X...).
 *
 * If the pain of reading these is too great, it should be a straightforward
 * task to translate them into Linux-specific versions which are more
 * consistent with the style used in NFSv2/v3...
 */
#define WRITE32(n)               *p++ = htonl(n)
#define WRITE64(n)               do {                           \
        *p++ = htonl((uint32_t)((n) >> 32));                            \
        *p++ = htonl((uint32_t)(n));                                    \
} while (0)
#define WRITEMEM(ptr,nbytes)     do {                           \
        p = xdr_encode_opaque_fixed(p, ptr, nbytes);            \
} while (0)

#define RESERVE_SPACE(nbytes)   do {                            \
        p = xdr_reserve_space(xdr, nbytes);                     \
        BUG_ON(!p);                                             \
} while (0)

static void encode_string(struct xdr_stream *xdr, unsigned int len, const char *str)
{
        __be32 *p;

        p = xdr_reserve_space(xdr, 4 + len);
        BUG_ON(p == NULL);
        xdr_encode_opaque(p, str, len);
}

static int encode_compound_hdr(struct xdr_stream *xdr, struct compound_hdr *hdr)
{
        __be32 *p;

        dprintk("encode_compound: tag=%.*s\n", (int)hdr->taglen, hdr->tag);
        BUG_ON(hdr->taglen > NFS4_MAXTAGLEN);
        RESERVE_SPACE(12+(XDR_QUADLEN(hdr->taglen)<<2));
        WRITE32(hdr->taglen);
        WRITEMEM(hdr->tag, hdr->taglen);
        WRITE32(NFS4_MINOR_VERSION);
        WRITE32(hdr->nops);
        return 0;
}

static void encode_nfs4_verifier(struct xdr_stream *xdr, const nfs4_verifier *verf)
{
        __be32 *p;

        p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
        BUG_ON(p == NULL);
        xdr_encode_opaque_fixed(p, verf->data, NFS4_VERIFIER_SIZE);
}

static int encode_attrs(struct xdr_stream *xdr, const struct iattr *iap, const struct nfs_server *server)
{
        char owner_name[IDMAP_NAMESZ];
        char owner_group[IDMAP_NAMESZ];
        int owner_namelen = 0;
        int owner_grouplen = 0;
        __be32 *p;
        __be32 *q;
        int len;
        uint32_t bmval0 = 0;
        uint32_t bmval1 = 0;
        int status;

        /*
         * We reserve enough space to write the entire attribute buffer at once.
         * In the worst-case, this would be
         *   12(bitmap) + 4(attrlen) + 8(size) + 4(mode) + 4(atime) + 4(mtime)
         *          = 36 bytes, plus any contribution from variable-length fields
         *            such as owner/group.
         */
        len = 16;

        /* Sigh */
        if (iap->ia_valid & ATTR_SIZE)
                len += 8;
        if (iap->ia_valid & ATTR_MODE)
                len += 4;
        if (iap->ia_valid & ATTR_UID) {
                owner_namelen = nfs_map_uid_to_name(server->nfs_client, iap->ia_uid, owner_name);
                if (owner_namelen < 0) {
                        dprintk("nfs: couldn't resolve uid %d to string\n",
                                        iap->ia_uid);
                        /* XXX */
                        strcpy(owner_name, "nobody");
                        owner_namelen = sizeof("nobody") - 1;
                        /* goto out; */
                }
                len += 4 + (XDR_QUADLEN(owner_namelen) << 2);
        }
        if (iap->ia_valid & ATTR_GID) {
                owner_grouplen = nfs_map_gid_to_group(server->nfs_client, iap->ia_gid, owner_group);
                if (owner_grouplen < 0) {
                        dprintk("nfs: couldn't resolve gid %d to string\n",
                                        iap->ia_gid);
                        strcpy(owner_group, "nobody");
                        owner_grouplen = sizeof("nobody") - 1;
                        /* goto out; */
                }
                len += 4 + (XDR_QUADLEN(owner_grouplen) << 2);
        }
        if (iap->ia_valid & ATTR_ATIME_SET)
                len += 16;
        else if (iap->ia_valid & ATTR_ATIME)
                len += 4;
        if (iap->ia_valid & ATTR_MTIME_SET)
                len += 16;
        else if (iap->ia_valid & ATTR_MTIME)
                len += 4;
        RESERVE_SPACE(len);

        /*
         * We write the bitmap length now, but leave the bitmap and the attribute
         * buffer length to be backfilled at the end of this routine.
         */
        WRITE32(2);
        q = p;
        p += 3;

        if (iap->ia_valid & ATTR_SIZE) {
                bmval0 |= FATTR4_WORD0_SIZE;
                WRITE64(iap->ia_size);
        }
        if (iap->ia_valid & ATTR_MODE) {
                bmval1 |= FATTR4_WORD1_MODE;
                WRITE32(iap->ia_mode & S_IALLUGO);
        }
        if (iap->ia_valid & ATTR_UID) {
                bmval1 |= FATTR4_WORD1_OWNER;
                WRITE32(owner_namelen);
                WRITEMEM(owner_name, owner_namelen);
        }
        if (iap->ia_valid & ATTR_GID) {
                bmval1 |= FATTR4_WORD1_OWNER_GROUP;
                WRITE32(owner_grouplen);
                WRITEMEM(owner_group, owner_grouplen);
        }
        if (iap->ia_valid & ATTR_ATIME_SET) {
                bmval1 |= FATTR4_WORD1_TIME_ACCESS_SET;
                WRITE32(NFS4_SET_TO_CLIENT_TIME);
                WRITE32(0);
                WRITE32(iap->ia_mtime.tv_sec);
                WRITE32(iap->ia_mtime.tv_nsec);
        }
        else if (iap->ia_valid & ATTR_ATIME) {
                bmval1 |= FATTR4_WORD1_TIME_ACCESS_SET;
                WRITE32(NFS4_SET_TO_SERVER_TIME);
        }
        if (iap->ia_valid & ATTR_MTIME_SET) {
                bmval1 |= FATTR4_WORD1_TIME_MODIFY_SET;
                WRITE32(NFS4_SET_TO_CLIENT_TIME);
                WRITE32(0);
                WRITE32(iap->ia_mtime.tv_sec);
                WRITE32(iap->ia_mtime.tv_nsec);
        }
        else if (iap->ia_valid & ATTR_MTIME) {
                bmval1 |= FATTR4_WORD1_TIME_MODIFY_SET;
                WRITE32(NFS4_SET_TO_SERVER_TIME);
        }
        
        /*
         * Now we backfill the bitmap and the attribute buffer length.
         */
        if (len != ((char *)p - (char *)q) + 4) {
                printk(KERN_ERR "nfs: Attr length error, %u != %Zu\n",
                                len, ((char *)p - (char *)q) + 4);
                BUG();
        }
        len = (char *)p - (char *)q - 12;
        *q++ = htonl(bmval0);
        *q++ = htonl(bmval1);
        *q++ = htonl(len);

        status = 0;
/* out: */
        return status;
}

static int encode_access(struct xdr_stream *xdr, u32 access)
{
        __be32 *p;

        RESERVE_SPACE(8);
        WRITE32(OP_ACCESS);
        WRITE32(access);
        
        return 0;
}

static int encode_close(struct xdr_stream *xdr, const struct nfs_closeargs *arg)
{
        __be32 *p;

        RESERVE_SPACE(8+NFS4_STATEID_SIZE);
        WRITE32(OP_CLOSE);
        WRITE32(arg->seqid->sequence->counter);
        WRITEMEM(arg->stateid->data, NFS4_STATEID_SIZE);
        
        return 0;
}

static int encode_commit(struct xdr_stream *xdr, const struct nfs_writeargs *args)
{
        __be32 *p;
        
        RESERVE_SPACE(16);
        WRITE32(OP_COMMIT);
        WRITE64(args->offset);
        WRITE32(args->count);

        return 0;
}

static int encode_create(struct xdr_stream *xdr, const struct nfs4_create_arg *create)
{
        __be32 *p;
        
        RESERVE_SPACE(8);
        WRITE32(OP_CREATE);
        WRITE32(create->ftype);

        switch (create->ftype) {
        case NF4LNK:
                RESERVE_SPACE(4);
                WRITE32(create->u.symlink.len);
                xdr_write_pages(xdr, create->u.symlink.pages, 0, create->u.symlink.len);
                break;

        case NF4BLK: case NF4CHR:
                RESERVE_SPACE(8);
                WRITE32(create->u.device.specdata1);
                WRITE32(create->u.device.specdata2);
                break;

        default:
                break;
        }

        RESERVE_SPACE(4 + create->name->len);
        WRITE32(create->name->len);
        WRITEMEM(create->name->name, create->name->len);

        return encode_attrs(xdr, create->attrs, create->server);
}

static int encode_getattr_one(struct xdr_stream *xdr, uint32_t bitmap)
{
        __be32 *p;

        RESERVE_SPACE(12);
        WRITE32(OP_GETATTR);
        WRITE32(1);
        WRITE32(bitmap);
        return 0;
}

static int encode_getattr_two(struct xdr_stream *xdr, uint32_t bm0, uint32_t bm1)
{
        __be32 *p;

        RESERVE_SPACE(16);
        WRITE32(OP_GETATTR);
        WRITE32(2);
        WRITE32(bm0);
        WRITE32(bm1);
        return 0;
}

static int encode_getfattr(struct xdr_stream *xdr, const u32* bitmask)
{
        return encode_getattr_two(xdr,
                        bitmask[0] & nfs4_fattr_bitmap[0],
                        bitmask[1] & nfs4_fattr_bitmap[1]);
}

static int encode_fsinfo(struct xdr_stream *xdr, const u32* bitmask)
{
        return encode_getattr_two(xdr, bitmask[0] & nfs4_fsinfo_bitmap[0],
                        bitmask[1] & nfs4_fsinfo_bitmap[1]);
}

static int encode_fs_locations(struct xdr_stream *xdr, const u32* bitmask)
{
        return encode_getattr_two(xdr,
                                  bitmask[0] & nfs4_fs_locations_bitmap[0],
                                  bitmask[1] & nfs4_fs_locations_bitmap[1]);
}

static int encode_getfh(struct xdr_stream *xdr)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(OP_GETFH);

        return 0;
}

static int encode_link(struct xdr_stream *xdr, const struct qstr *name)
{
        __be32 *p;

        RESERVE_SPACE(8 + name->len);
        WRITE32(OP_LINK);
        WRITE32(name->len);
        WRITEMEM(name->name, name->len);
        
        return 0;
}

static inline int nfs4_lock_type(struct file_lock *fl, int block)
{
        if ((fl->fl_type & (F_RDLCK|F_WRLCK|F_UNLCK)) == F_RDLCK)
                return block ? NFS4_READW_LT : NFS4_READ_LT;
        return block ? NFS4_WRITEW_LT : NFS4_WRITE_LT;
}

static inline uint64_t nfs4_lock_length(struct file_lock *fl)
{
        if (fl->fl_end == OFFSET_MAX)
                return ~(uint64_t)0;
        return fl->fl_end - fl->fl_start + 1;
}

/*
 * opcode,type,reclaim,offset,length,new_lock_owner = 32
 * open_seqid,open_stateid,lock_seqid,lock_owner.clientid, lock_owner.id = 40
 */
static int encode_lock(struct xdr_stream *xdr, const struct nfs_lock_args *args)
{
        __be32 *p;

        RESERVE_SPACE(32);
        WRITE32(OP_LOCK);
        WRITE32(nfs4_lock_type(args->fl, args->block));
        WRITE32(args->reclaim);
        WRITE64(args->fl->fl_start);
        WRITE64(nfs4_lock_length(args->fl));
        WRITE32(args->new_lock_owner);
        if (args->new_lock_owner){
                RESERVE_SPACE(4+NFS4_STATEID_SIZE+32);
                WRITE32(args->open_seqid->sequence->counter);
                WRITEMEM(args->open_stateid->data, NFS4_STATEID_SIZE);
                WRITE32(args->lock_seqid->sequence->counter);
                WRITE64(args->lock_owner.clientid);
                WRITE32(16);
                WRITEMEM("lock id:", 8);
                WRITE64(args->lock_owner.id);
        }
        else {
                RESERVE_SPACE(NFS4_STATEID_SIZE+4);
                WRITEMEM(args->lock_stateid->data, NFS4_STATEID_SIZE);
                WRITE32(args->lock_seqid->sequence->counter);
        }

        return 0;
}

static int encode_lockt(struct xdr_stream *xdr, const struct nfs_lockt_args *args)
{
        __be32 *p;

        RESERVE_SPACE(52);
        WRITE32(OP_LOCKT);
        WRITE32(nfs4_lock_type(args->fl, 0));
        WRITE64(args->fl->fl_start);
        WRITE64(nfs4_lock_length(args->fl));
        WRITE64(args->lock_owner.clientid);
        WRITE32(16);
        WRITEMEM("lock id:", 8);
        WRITE64(args->lock_owner.id);

        return 0;
}

static int encode_locku(struct xdr_stream *xdr, const struct nfs_locku_args *args)
{
        __be32 *p;

        RESERVE_SPACE(12+NFS4_STATEID_SIZE+16);
        WRITE32(OP_LOCKU);
        WRITE32(nfs4_lock_type(args->fl, 0));
        WRITE32(args->seqid->sequence->counter);
        WRITEMEM(args->stateid->data, NFS4_STATEID_SIZE);
        WRITE64(args->fl->fl_start);
        WRITE64(nfs4_lock_length(args->fl));

        return 0;
}

static int encode_lookup(struct xdr_stream *xdr, const struct qstr *name)
{
        int len = name->len;
        __be32 *p;

        RESERVE_SPACE(8 + len);
        WRITE32(OP_LOOKUP);
        WRITE32(len);
        WRITEMEM(name->name, len);

        return 0;
}

static void encode_share_access(struct xdr_stream *xdr, int open_flags)
{
        __be32 *p;

        RESERVE_SPACE(8);
        switch (open_flags & (FMODE_READ|FMODE_WRITE)) {
                case FMODE_READ:
                        WRITE32(NFS4_SHARE_ACCESS_READ);
                        break;
                case FMODE_WRITE:
                        WRITE32(NFS4_SHARE_ACCESS_WRITE);
                        break;
                case FMODE_READ|FMODE_WRITE:
                        WRITE32(NFS4_SHARE_ACCESS_BOTH);
                        break;
                default:
                        BUG();
        }
        WRITE32(0);             /* for linux, share_deny = 0 always */
}

static inline void encode_openhdr(struct xdr_stream *xdr, const struct nfs_openargs *arg)
{
        __be32 *p;
 /*
 * opcode 4, seqid 4, share_access 4, share_deny 4, clientid 8, ownerlen 4,
 * owner 4 = 32
 */
        RESERVE_SPACE(8);
        WRITE32(OP_OPEN);
        WRITE32(arg->seqid->sequence->counter);
        encode_share_access(xdr, arg->open_flags);
        RESERVE_SPACE(28);
        WRITE64(arg->clientid);
        WRITE32(16);
        WRITEMEM("open id:", 8);
        WRITE64(arg->id);
}

static inline void encode_createmode(struct xdr_stream *xdr, const struct nfs_openargs *arg)
{
        __be32 *p;

        RESERVE_SPACE(4);
        switch(arg->open_flags & O_EXCL) {

                case 0:
                        WRITE32(NFS4_CREATE_UNCHECKED);
                        encode_attrs(xdr, arg->u.attrs, arg->server);
                        break;
                default:
                        WRITE32(NFS4_CREATE_EXCLUSIVE);
                        encode_nfs4_verifier(xdr, &arg->u.verifier);
        }
}

static void encode_opentype(struct xdr_stream *xdr, const struct nfs_openargs *arg)
{
        __be32 *p;

        RESERVE_SPACE(4);
        switch (arg->open_flags & O_CREAT) {
                case 0:
                        WRITE32(NFS4_OPEN_NOCREATE);
                        break;
                default:
                        BUG_ON(arg->claim != NFS4_OPEN_CLAIM_NULL);
                        WRITE32(NFS4_OPEN_CREATE);
                        encode_createmode(xdr, arg);
        }
}

static inline void encode_delegation_type(struct xdr_stream *xdr, int delegation_type)
{
        __be32 *p;

        RESERVE_SPACE(4);
        switch (delegation_type) {
                case 0:
                        WRITE32(NFS4_OPEN_DELEGATE_NONE);
                        break;
                case FMODE_READ:
                        WRITE32(NFS4_OPEN_DELEGATE_READ);
                        break;
                case FMODE_WRITE|FMODE_READ:
                        WRITE32(NFS4_OPEN_DELEGATE_WRITE);
                        break;
                default:
                        BUG();
        }
}

static inline void encode_claim_null(struct xdr_stream *xdr, const struct qstr *name)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(NFS4_OPEN_CLAIM_NULL);
        encode_string(xdr, name->len, name->name);
}

static inline void encode_claim_previous(struct xdr_stream *xdr, int type)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(NFS4_OPEN_CLAIM_PREVIOUS);
        encode_delegation_type(xdr, type);
}

static inline void encode_claim_delegate_cur(struct xdr_stream *xdr, const struct qstr *name, const nfs4_stateid *stateid)
{
        __be32 *p;

        RESERVE_SPACE(4+NFS4_STATEID_SIZE);
        WRITE32(NFS4_OPEN_CLAIM_DELEGATE_CUR);
        WRITEMEM(stateid->data, NFS4_STATEID_SIZE);
        encode_string(xdr, name->len, name->name);
}

static int encode_open(struct xdr_stream *xdr, const struct nfs_openargs *arg)
{
        encode_openhdr(xdr, arg);
        encode_opentype(xdr, arg);
        switch (arg->claim) {
                case NFS4_OPEN_CLAIM_NULL:
                        encode_claim_null(xdr, arg->name);
                        break;
                case NFS4_OPEN_CLAIM_PREVIOUS:
                        encode_claim_previous(xdr, arg->u.delegation_type);
                        break;
                case NFS4_OPEN_CLAIM_DELEGATE_CUR:
                        encode_claim_delegate_cur(xdr, arg->name, &arg->u.delegation);
                        break;
                default:
                        BUG();
        }
        return 0;
}

static int encode_open_confirm(struct xdr_stream *xdr, const struct nfs_open_confirmargs *arg)
{
        __be32 *p;

        RESERVE_SPACE(4+NFS4_STATEID_SIZE+4);
        WRITE32(OP_OPEN_CONFIRM);
        WRITEMEM(arg->stateid->data, NFS4_STATEID_SIZE);
        WRITE32(arg->seqid->sequence->counter);

        return 0;
}

static int encode_open_downgrade(struct xdr_stream *xdr, const struct nfs_closeargs *arg)
{
        __be32 *p;

        RESERVE_SPACE(4+NFS4_STATEID_SIZE+4);
        WRITE32(OP_OPEN_DOWNGRADE);
        WRITEMEM(arg->stateid->data, NFS4_STATEID_SIZE);
        WRITE32(arg->seqid->sequence->counter);
        encode_share_access(xdr, arg->open_flags);
        return 0;
}

static int
encode_putfh(struct xdr_stream *xdr, const struct nfs_fh *fh)
{
        int len = fh->size;
        __be32 *p;

        RESERVE_SPACE(8 + len);
        WRITE32(OP_PUTFH);
        WRITE32(len);
        WRITEMEM(fh->data, len);

        return 0;
}

static int encode_putrootfh(struct xdr_stream *xdr)
{
        __be32 *p;
        
        RESERVE_SPACE(4);
        WRITE32(OP_PUTROOTFH);

        return 0;
}

static void encode_stateid(struct xdr_stream *xdr, const struct nfs_open_context *ctx)
{
        nfs4_stateid stateid;
        __be32 *p;

        RESERVE_SPACE(NFS4_STATEID_SIZE);
        if (ctx->state != NULL) {
                nfs4_copy_stateid(&stateid, ctx->state, ctx->lockowner);
                WRITEMEM(stateid.data, NFS4_STATEID_SIZE);
        } else
                WRITEMEM(zero_stateid.data, NFS4_STATEID_SIZE);
}

static int encode_read(struct xdr_stream *xdr, const struct nfs_readargs *args)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(OP_READ);

        encode_stateid(xdr, args->context);

        RESERVE_SPACE(12);
        WRITE64(args->offset);
        WRITE32(args->count);

        return 0;
}

static int encode_readdir(struct xdr_stream *xdr, const struct nfs4_readdir_arg *readdir, struct rpc_rqst *req)
{
        uint32_t attrs[2] = {
                FATTR4_WORD0_RDATTR_ERROR|FATTR4_WORD0_FILEID,
                FATTR4_WORD1_MOUNTED_ON_FILEID,
        };
        __be32 *p;

        RESERVE_SPACE(12+NFS4_VERIFIER_SIZE+20);
        WRITE32(OP_READDIR);
        WRITE64(readdir->cookie);
        WRITEMEM(readdir->verifier.data, NFS4_VERIFIER_SIZE);
        WRITE32(readdir->count >> 1);  /* We're not doing readdirplus */
        WRITE32(readdir->count);
        WRITE32(2);
        /* Switch to mounted_on_fileid if the server supports it */
        if (readdir->bitmask[1] & FATTR4_WORD1_MOUNTED_ON_FILEID)
                attrs[0] &= ~FATTR4_WORD0_FILEID;
        else
                attrs[1] &= ~FATTR4_WORD1_MOUNTED_ON_FILEID;
        WRITE32(attrs[0] & readdir->bitmask[0]);
        WRITE32(attrs[1] & readdir->bitmask[1]);
        dprintk("%s: cookie = %Lu, verifier = %08x:%08x, bitmap = %08x:%08x\n",
                        __func__,
                        (unsigned long long)readdir->cookie,
                        ((u32 *)readdir->verifier.data)[0],
                        ((u32 *)readdir->verifier.data)[1],
                        attrs[0] & readdir->bitmask[0],
                        attrs[1] & readdir->bitmask[1]);

        return 0;
}

static int encode_readlink(struct xdr_stream *xdr, const struct nfs4_readlink *readlink, struct rpc_rqst *req)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(OP_READLINK);

        return 0;
}

static int encode_remove(struct xdr_stream *xdr, const struct qstr *name)
{
        __be32 *p;

        RESERVE_SPACE(8 + name->len);
        WRITE32(OP_REMOVE);
        WRITE32(name->len);
        WRITEMEM(name->name, name->len);

        return 0;
}

static int encode_rename(struct xdr_stream *xdr, const struct qstr *oldname, const struct qstr *newname)
{
        __be32 *p;

        RESERVE_SPACE(8 + oldname->len);
        WRITE32(OP_RENAME);
        WRITE32(oldname->len);
        WRITEMEM(oldname->name, oldname->len);
        
        RESERVE_SPACE(4 + newname->len);
        WRITE32(newname->len);
        WRITEMEM(newname->name, newname->len);

        return 0;
}

static int encode_renew(struct xdr_stream *xdr, const struct nfs_client *client_stateid)
{
        __be32 *p;

        RESERVE_SPACE(12);
        WRITE32(OP_RENEW);
        WRITE64(client_stateid->cl_clientid);

        return 0;
}

static int
encode_restorefh(struct xdr_stream *xdr)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(OP_RESTOREFH);

        return 0;
}

static int
encode_setacl(struct xdr_stream *xdr, struct nfs_setaclargs *arg)
{
        __be32 *p;

        RESERVE_SPACE(4+NFS4_STATEID_SIZE);
        WRITE32(OP_SETATTR);
        WRITEMEM(zero_stateid.data, NFS4_STATEID_SIZE);
        RESERVE_SPACE(2*4);
        WRITE32(1);
        WRITE32(FATTR4_WORD0_ACL);
        if (arg->acl_len % 4)
                return -EINVAL;
        RESERVE_SPACE(4);
        WRITE32(arg->acl_len);
        xdr_write_pages(xdr, arg->acl_pages, arg->acl_pgbase, arg->acl_len);
        return 0;
}

static int
encode_savefh(struct xdr_stream *xdr)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(OP_SAVEFH);

        return 0;
}

static int encode_setattr(struct xdr_stream *xdr, const struct nfs_setattrargs *arg, const struct nfs_server *server)
{
        int status;
        __be32 *p;
        
        RESERVE_SPACE(4+NFS4_STATEID_SIZE);
        WRITE32(OP_SETATTR);
        WRITEMEM(arg->stateid.data, NFS4_STATEID_SIZE);

        if ((status = encode_attrs(xdr, arg->iap, server)))
                return status;

        return 0;
}

static int encode_setclientid(struct xdr_stream *xdr, const struct nfs4_setclientid *setclientid)
{
        __be32 *p;

        RESERVE_SPACE(4 + NFS4_VERIFIER_SIZE);
        WRITE32(OP_SETCLIENTID);
        WRITEMEM(setclientid->sc_verifier->data, NFS4_VERIFIER_SIZE);

        encode_string(xdr, setclientid->sc_name_len, setclientid->sc_name);
        RESERVE_SPACE(4);
        WRITE32(setclientid->sc_prog);
        encode_string(xdr, setclientid->sc_netid_len, setclientid->sc_netid);
        encode_string(xdr, setclientid->sc_uaddr_len, setclientid->sc_uaddr);
        RESERVE_SPACE(4);
        WRITE32(setclientid->sc_cb_ident);

        return 0;
}

static int encode_setclientid_confirm(struct xdr_stream *xdr, const struct nfs_client *client_state)
{
        __be32 *p;

        RESERVE_SPACE(12 + NFS4_VERIFIER_SIZE);
        WRITE32(OP_SETCLIENTID_CONFIRM);
        WRITE64(client_state->cl_clientid);
        WRITEMEM(client_state->cl_confirm.data, NFS4_VERIFIER_SIZE);

        return 0;
}

static int encode_write(struct xdr_stream *xdr, const struct nfs_writeargs *args)
{
        __be32 *p;

        RESERVE_SPACE(4);
        WRITE32(OP_WRITE);

        encode_stateid(xdr, args->context);

        RESERVE_SPACE(16);
        WRITE64(args->offset);
        WRITE32(args->stable);
        WRITE32(args->count);

        xdr_write_pages(xdr, args->pages, args->pgbase, args->count);

        return 0;
}

static int encode_delegreturn(struct xdr_stream *xdr, const nfs4_stateid *stateid)
{
        __be32 *p;

        RESERVE_SPACE(4+NFS4_STATEID_SIZE);

        WRITE32(OP_DELEGRETURN);
        WRITEMEM(stateid->data, NFS4_STATEID_SIZE);
        return 0;

}
/*
 * END OF "GENERIC" ENCODE ROUTINES.
 */

/*
 * Encode an ACCESS request
 */
static int nfs4_xdr_enc_access(struct rpc_rqst *req, __be32 *p, const struct nfs4_accessargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status != 0)
                goto out;
        status = encode_access(&xdr, args->access);
        if (status != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode LOOKUP request
 */
static int nfs4_xdr_enc_lookup(struct rpc_rqst *req, __be32 *p, const struct nfs4_lookup_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 4,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putfh(&xdr, args->dir_fh)) != 0)
                goto out;
        if ((status = encode_lookup(&xdr, args->name)) != 0)
                goto out;
        if ((status = encode_getfh(&xdr)) != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode LOOKUP_ROOT request
 */
static int nfs4_xdr_enc_lookup_root(struct rpc_rqst *req, __be32 *p, const struct nfs4_lookup_root_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putrootfh(&xdr)) != 0)
                goto out;
        if ((status = encode_getfh(&xdr)) == 0)
                status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode REMOVE request
 */
static int nfs4_xdr_enc_remove(struct rpc_rqst *req, __be32 *p, const struct nfs_removeargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putfh(&xdr, args->fh)) != 0)
                goto out;
        if ((status = encode_remove(&xdr, &args->name)) != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode RENAME request
 */
static int nfs4_xdr_enc_rename(struct rpc_rqst *req, __be32 *p, const struct nfs4_rename_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 7,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putfh(&xdr, args->old_dir)) != 0)
                goto out;
        if ((status = encode_savefh(&xdr)) != 0)
                goto out;
        if ((status = encode_putfh(&xdr, args->new_dir)) != 0)
                goto out;
        if ((status = encode_rename(&xdr, args->old_name, args->new_name)) != 0)
                goto out;
        if ((status = encode_getfattr(&xdr, args->bitmask)) != 0)
                goto out;
        if ((status = encode_restorefh(&xdr)) != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode LINK request
 */
static int nfs4_xdr_enc_link(struct rpc_rqst *req, __be32 *p, const struct nfs4_link_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 7,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putfh(&xdr, args->fh)) != 0)
                goto out;
        if ((status = encode_savefh(&xdr)) != 0)
                goto out;
        if ((status = encode_putfh(&xdr, args->dir_fh)) != 0)
                goto out;
        if ((status = encode_link(&xdr, args->name)) != 0)
                goto out;
        if ((status = encode_getfattr(&xdr, args->bitmask)) != 0)
                goto out;
        if ((status = encode_restorefh(&xdr)) != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode CREATE request
 */
static int nfs4_xdr_enc_create(struct rpc_rqst *req, __be32 *p, const struct nfs4_create_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 7,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putfh(&xdr, args->dir_fh)) != 0)
                goto out;
        if ((status = encode_savefh(&xdr)) != 0)
                goto out;
        if ((status = encode_create(&xdr, args)) != 0)
                goto out;
        if ((status = encode_getfh(&xdr)) != 0)
                goto out;
        if ((status = encode_getfattr(&xdr, args->bitmask)) != 0)
                goto out;
        if ((status = encode_restorefh(&xdr)) != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode SYMLINK request
 */
static int nfs4_xdr_enc_symlink(struct rpc_rqst *req, __be32 *p, const struct nfs4_create_arg *args)
{
        return nfs4_xdr_enc_create(req, p, args);
}

/*
 * Encode GETATTR request
 */
static int nfs4_xdr_enc_getattr(struct rpc_rqst *req, __be32 *p, const struct nfs4_getattr_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putfh(&xdr, args->fh)) == 0)
                status = encode_getfattr(&xdr, args->bitmask);
        return status;
}

/*
 * Encode a CLOSE request
 */
static int nfs4_xdr_enc_close(struct rpc_rqst *req, __be32 *p, struct nfs_closeargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_close(&xdr, args);
        if (status != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode an OPEN request
 */
static int nfs4_xdr_enc_open(struct rpc_rqst *req, __be32 *p, struct nfs_openargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 7,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status)
                goto out;
        status = encode_savefh(&xdr);
        if (status)
                goto out;
        status = encode_open(&xdr, args);
        if (status)
                goto out;
        status = encode_getfh(&xdr);
        if (status)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
        if (status)
                goto out;
        status = encode_restorefh(&xdr);
        if (status)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode an OPEN_CONFIRM request
 */
static int nfs4_xdr_enc_open_confirm(struct rpc_rqst *req, __be32 *p, struct nfs_open_confirmargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_open_confirm(&xdr, args);
out:
        return status;
}

/*
 * Encode an OPEN request with no attributes.
 */
static int nfs4_xdr_enc_open_noattr(struct rpc_rqst *req, __be32 *p, struct nfs_openargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status)
                goto out;
        status = encode_open(&xdr, args);
        if (status)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode an OPEN_DOWNGRADE request
 */
static int nfs4_xdr_enc_open_downgrade(struct rpc_rqst *req, __be32 *p, struct nfs_closeargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status)
                goto out;
        status = encode_open_downgrade(&xdr, args);
        if (status != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode a LOCK request
 */
static int nfs4_xdr_enc_lock(struct rpc_rqst *req, __be32 *p, struct nfs_lock_args *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_lock(&xdr, args);
out:
        return status;
}

/*
 * Encode a LOCKT request
 */
static int nfs4_xdr_enc_lockt(struct rpc_rqst *req, __be32 *p, struct nfs_lockt_args *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_lockt(&xdr, args);
out:
        return status;
}

/*
 * Encode a LOCKU request
 */
static int nfs4_xdr_enc_locku(struct rpc_rqst *req, __be32 *p, struct nfs_locku_args *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_locku(&xdr, args);
out:
        return status;
}

/*
 * Encode a READLINK request
 */
static int nfs4_xdr_enc_readlink(struct rpc_rqst *req, __be32 *p, const struct nfs4_readlink *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 2,
        };
        struct rpc_auth *auth = req->rq_task->tk_msg.rpc_cred->cr_auth;
        unsigned int replen;
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_readlink(&xdr, args, req);

        /* set up reply kvec
         *    toplevel_status + taglen + rescount + OP_PUTFH + status
         *      + OP_READLINK + status + string length = 8
         */
        replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS4_dec_readlink_sz) << 2;
        xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages,
                        args->pgbase, args->pglen);

out:
        return status;
}

/*
 * Encode a READDIR request
 */
static int nfs4_xdr_enc_readdir(struct rpc_rqst *req, __be32 *p, const struct nfs4_readdir_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 2,
        };
        struct rpc_auth *auth = req->rq_task->tk_msg.rpc_cred->cr_auth;
        int replen;
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_readdir(&xdr, args, req);

        /* set up reply kvec
         *    toplevel_status + taglen + rescount + OP_PUTFH + status
         *      + OP_READDIR + status + verifer(2)  = 9
         */
        replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS4_dec_readdir_sz) << 2;
        xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages,
                         args->pgbase, args->count);
        dprintk("%s: inlined page args = (%u, %p, %u, %u)\n",
                        __func__, replen, args->pages,
                        args->pgbase, args->count);

out:
        return status;
}

/*
 * Encode a READ request
 */
static int nfs4_xdr_enc_read(struct rpc_rqst *req, __be32 *p, struct nfs_readargs *args)
{
        struct rpc_auth *auth = req->rq_task->tk_msg.rpc_cred->cr_auth;
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 2,
        };
        int replen, status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status)
                goto out;
        status = encode_read(&xdr, args);
        if (status)
                goto out;

        /* set up reply kvec
         *    toplevel status + taglen=0 + rescount + OP_PUTFH + status
         *       + OP_READ + status + eof + datalen = 9
         */
        replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS4_dec_read_sz) << 2;
        xdr_inline_pages(&req->rq_rcv_buf, replen,
                         args->pages, args->pgbase, args->count);
        req->rq_rcv_buf.flags |= XDRBUF_READ;
out:
        return status;
}

/*
 * Encode an SETATTR request
 */
static int nfs4_xdr_enc_setattr(struct rpc_rqst *req, __be32 *p, struct nfs_setattrargs *args)

{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if(status)
                goto out;
        status = encode_setattr(&xdr, args, args->server);
        if(status)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode a GETACL request
 */
static int
nfs4_xdr_enc_getacl(struct rpc_rqst *req, __be32 *p,
                struct nfs_getaclargs *args)
{
        struct xdr_stream xdr;
        struct rpc_auth *auth = req->rq_task->tk_msg.rpc_cred->cr_auth;
        struct compound_hdr hdr = {
                .nops   = 2,
        };
        int replen, status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status)
                goto out;
        status = encode_getattr_two(&xdr, FATTR4_WORD0_ACL, 0);
        /* set up reply buffer: */
        replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS4_dec_getacl_sz) << 2;
        xdr_inline_pages(&req->rq_rcv_buf, replen,
                args->acl_pages, args->acl_pgbase, args->acl_len);
out:
        return status;
}

/*
 * Encode a WRITE request
 */
static int nfs4_xdr_enc_write(struct rpc_rqst *req, __be32 *p, struct nfs_writeargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status)
                goto out;
        status = encode_write(&xdr, args);
        if (status)
                goto out;
        req->rq_snd_buf.flags |= XDRBUF_WRITE;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 *  a COMMIT request
 */
static int nfs4_xdr_enc_commit(struct rpc_rqst *req, __be32 *p, struct nfs_writeargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status)
                goto out;
        status = encode_commit(&xdr, args);
        if (status)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * FSINFO request
 */
static int nfs4_xdr_enc_fsinfo(struct rpc_rqst *req, __be32 *p, struct nfs4_fsinfo_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (!status)
                status = encode_fsinfo(&xdr, args->bitmask);
        return status;
}

/*
 * a PATHCONF request
 */
static int nfs4_xdr_enc_pathconf(struct rpc_rqst *req, __be32 *p, const struct nfs4_pathconf_arg *args)
{
        struct xdr_stream xdr;

        struct compound_hdr hdr = {
                .nops = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (!status)
                status = encode_getattr_one(&xdr,
                                args->bitmask[0] & nfs4_pathconf_bitmap[0]);
        return status;
}

/*
 * a STATFS request
 */
static int nfs4_xdr_enc_statfs(struct rpc_rqst *req, __be32 *p, const struct nfs4_statfs_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fh);
        if (status == 0)
                status = encode_getattr_two(&xdr,
                                args->bitmask[0] & nfs4_statfs_bitmap[0],
                                args->bitmask[1] & nfs4_statfs_bitmap[1]);
        return status;
}

/*
 * GETATTR_BITMAP request
 */
static int nfs4_xdr_enc_server_caps(struct rpc_rqst *req, __be32 *p, const struct nfs_fh *fhandle)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 2,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, fhandle);
        if (status == 0)
                status = encode_getattr_one(&xdr, FATTR4_WORD0_SUPPORTED_ATTRS|
                                FATTR4_WORD0_LINK_SUPPORT|
                                FATTR4_WORD0_SYMLINK_SUPPORT|
                                FATTR4_WORD0_ACLSUPPORT);
        return status;
}

/*
 * a RENEW request
 */
static int nfs4_xdr_enc_renew(struct rpc_rqst *req, __be32 *p, struct nfs_client *clp)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 1,
        };

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        return encode_renew(&xdr, clp);
}

/*
 * a SETCLIENTID request
 */
static int nfs4_xdr_enc_setclientid(struct rpc_rqst *req, __be32 *p, struct nfs4_setclientid *sc)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 1,
        };

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        return encode_setclientid(&xdr, sc);
}

/*
 * a SETCLIENTID_CONFIRM request
 */
static int nfs4_xdr_enc_setclientid_confirm(struct rpc_rqst *req, __be32 *p, struct nfs_client *clp)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops   = 3,
        };
        const u32 lease_bitmap[2] = { FATTR4_WORD0_LEASE_TIME, 0 };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_setclientid_confirm(&xdr, clp);
        if (!status)
                status = encode_putrootfh(&xdr);
        if (!status)
                status = encode_fsinfo(&xdr, lease_bitmap);
        return status;
}

/*
 * DELEGRETURN request
 */
static int nfs4_xdr_enc_delegreturn(struct rpc_rqst *req, __be32 *p, const struct nfs4_delegreturnargs *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 3,
        };
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        status = encode_putfh(&xdr, args->fhandle);
        if (status != 0)
                goto out;
        status = encode_delegreturn(&xdr, args->stateid);
        if (status != 0)
                goto out;
        status = encode_getfattr(&xdr, args->bitmask);
out:
        return status;
}

/*
 * Encode FS_LOCATIONS request
 */
static int nfs4_xdr_enc_fs_locations(struct rpc_rqst *req, __be32 *p, struct nfs4_fs_locations_arg *args)
{
        struct xdr_stream xdr;
        struct compound_hdr hdr = {
                .nops = 3,
        };
        struct rpc_auth *auth = req->rq_task->tk_msg.rpc_cred->cr_auth;
        int replen;
        int status;

        xdr_init_encode(&xdr, &req->rq_snd_buf, p);
        encode_compound_hdr(&xdr, &hdr);
        if ((status = encode_putfh(&xdr, args->dir_fh)) != 0)
                goto out;
        if ((status = encode_lookup(&xdr, args->name)) != 0)
                goto out;
        if ((status = encode_fs_locations(&xdr, args->bitmask)) != 0)
                goto out;
        /* set up reply
         *   toplevel_status + OP_PUTFH + status
         *   + OP_LOOKUP + status + OP_GETATTR + status = 7
         */
        replen = (RPC_REPHDRSIZE + auth->au_rslack + 7) << 2;
        xdr_inline_pages(&req->rq_rcv_buf, replen, &args->page,
                        0, PAGE_SIZE);
out:
        return status;
}

/*
 * START OF "GENERIC" DECODE ROUTINES.
 *   These may look a little ugly since they are imported from a "generic"
 * set of XDR encode/decode routines which are intended to be shared by
 * all of our NFSv4 implementations (OpenBSD, MacOS X...).
 *
 * If the pain of reading these is too great, it should be a straightforward
 * task to translate them into Linux-specific versions which are more
 * consistent with the style used in NFSv2/v3...
 */
#define READ32(x)         (x) = ntohl(*p++)
#define READ64(x)         do {                  \
        (x) = (u64)ntohl(*p++) << 32;           \
        (x) |= ntohl(*p++);                     \
} while (0)
#define READTIME(x)       do {                  \
        p++;                                    \
        (x.tv_sec) = ntohl(*p++);               \
        (x.tv_nsec) = ntohl(*p++);              \
} while (0)
#define COPYMEM(x,nbytes) do {                  \
        memcpy((x), p, nbytes);                 \
        p += XDR_QUADLEN(nbytes);               \
} while (0)

#define READ_BUF(nbytes)  do { \
        p = xdr_inline_decode(xdr, nbytes); \
        if (unlikely(!p)) { \
                dprintk("nfs: %s: prematurely hit end of receive" \
                                " buffer\n", __func__); \
                dprintk("nfs: %s: xdr->p=%p, bytes=%u, xdr->end=%p\n", \
                                __func__, xdr->p, nbytes, xdr->end); \
                return -EIO; \
        } \
} while (0)

static int decode_opaque_inline(struct xdr_stream *xdr, unsigned int *len, char **string)
{
        __be32 *p;

        READ_BUF(4);
        READ32(*len);
        READ_BUF(*len);
        *string = (char *)p;
        return 0;
}

static int decode_compound_hdr(struct xdr_stream *xdr, struct compound_hdr *hdr)
{
        __be32 *p;

        READ_BUF(8);
        READ32(hdr->status);
        READ32(hdr->taglen);
        
        READ_BUF(hdr->taglen + 4);
        hdr->tag = (char *)p;
        p += XDR_QUADLEN(hdr->taglen);
        READ32(hdr->nops);
        return 0;
}

static int decode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
{
        __be32 *p;
        uint32_t opnum;
        int32_t nfserr;

        READ_BUF(8);
        READ32(opnum);
        if (opnum != expected) {
                dprintk("nfs: Server returned operation"
                        " %d but we issued a request for %d\n",
                                opnum, expected);
                return -EIO;
        }
        READ32(nfserr);
        if (nfserr != NFS_OK)
                return nfs4_stat_to_errno(nfserr);
        return 0;
}

/* Dummy routine */
static int decode_ace(struct xdr_stream *xdr, void *ace, struct nfs_client *clp)
{
        __be32 *p;
        unsigned int strlen;
        char *str;

        READ_BUF(12);
        return decode_opaque_inline(xdr, &strlen, &str);
}

static int decode_attr_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
{
        uint32_t bmlen;
        __be32 *p;

        READ_BUF(4);
        READ32(bmlen);

        bitmap[0] = bitmap[1] = 0;
        READ_BUF((bmlen << 2));
        if (bmlen > 0) {
                READ32(bitmap[0]);
                if (bmlen > 1)
                        READ32(bitmap[1]);
        }
        return 0;
}

static inline int decode_attr_length(struct xdr_stream *xdr, uint32_t *attrlen, __be32 **savep)
{
        __be32 *p;

        READ_BUF(4);
        READ32(*attrlen);
        *savep = xdr->p;
        return 0;
}

static int decode_attr_supported(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *bitmask)
{
        if (likely(bitmap[0] & FATTR4_WORD0_SUPPORTED_ATTRS)) {
                decode_attr_bitmap(xdr, bitmask);
                bitmap[0] &= ~FATTR4_WORD0_SUPPORTED_ATTRS;
        } else
                bitmask[0] = bitmask[1] = 0;
        dprintk("%s: bitmask=%08x:%08x\n", __func__, bitmask[0], bitmask[1]);
        return 0;
}

static int decode_attr_type(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *type)
{
        __be32 *p;

        *type = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_TYPE - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_TYPE)) {
                READ_BUF(4);
                READ32(*type);
                if (*type < NF4REG || *type > NF4NAMEDATTR) {
                        dprintk("%s: bad type %d\n", __func__, *type);
                        return -EIO;
                }
                bitmap[0] &= ~FATTR4_WORD0_TYPE;
        }
        dprintk("%s: type=0%o\n", __func__, nfs_type2fmt[*type].nfs2type);
        return 0;
}

static int decode_attr_change(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *change)
{
        __be32 *p;

        *change = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_CHANGE - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_CHANGE)) {
                READ_BUF(8);
                READ64(*change);
                bitmap[0] &= ~FATTR4_WORD0_CHANGE;
        }
        dprintk("%s: change attribute=%Lu\n", __func__,
                        (unsigned long long)*change);
        return 0;
}

static int decode_attr_size(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *size)
{
        __be32 *p;

        *size = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_SIZE - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_SIZE)) {
                READ_BUF(8);
                READ64(*size);
                bitmap[0] &= ~FATTR4_WORD0_SIZE;
        }
        dprintk("%s: file size=%Lu\n", __func__, (unsigned long long)*size);
        return 0;
}

static int decode_attr_link_support(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
        __be32 *p;

        *res = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_LINK_SUPPORT - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_LINK_SUPPORT)) {
                READ_BUF(4);
                READ32(*res);
                bitmap[0] &= ~FATTR4_WORD0_LINK_SUPPORT;
        }
        dprintk("%s: link support=%s\n", __func__, *res == 0 ? "false" : "true");
        return 0;
}

static int decode_attr_symlink_support(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
        __be32 *p;

        *res = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_SYMLINK_SUPPORT - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_SYMLINK_SUPPORT)) {
                READ_BUF(4);
                READ32(*res);
                bitmap[0] &= ~FATTR4_WORD0_SYMLINK_SUPPORT;
        }
        dprintk("%s: symlink support=%s\n", __func__, *res == 0 ? "false" : "true");
        return 0;
}

static int decode_attr_fsid(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs_fsid *fsid)
{
        __be32 *p;

        fsid->major = 0;
        fsid->minor = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_FSID - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_FSID)) {
                READ_BUF(16);
                READ64(fsid->major);
                READ64(fsid->minor);
                bitmap[0] &= ~FATTR4_WORD0_FSID;
        }
        dprintk("%s: fsid=(0x%Lx/0x%Lx)\n", __func__,
                        (unsigned long long)fsid->major,
                        (unsigned long long)fsid->minor);
        return 0;
}

static int decode_attr_lease_time(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
        __be32 *p;

        *res = 60;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_LEASE_TIME - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_LEASE_TIME)) {
                READ_BUF(4);
                READ32(*res);
                bitmap[0] &= ~FATTR4_WORD0_LEASE_TIME;
        }
        dprintk("%s: file size=%u\n", __func__, (unsigned int)*res);
        return 0;
}

static int decode_attr_aclsupport(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
        __be32 *p;

        *res = ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_ACLSUPPORT - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_ACLSUPPORT)) {
                READ_BUF(4);
                READ32(*res);
                bitmap[0] &= ~FATTR4_WORD0_ACLSUPPORT;
        }
        dprintk("%s: ACLs supported=%u\n", __func__, (unsigned int)*res);
        return 0;
}

static int decode_attr_fileid(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *fileid)
{
        __be32 *p;

        *fileid = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_FILEID - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_FILEID)) {
                READ_BUF(8);
                READ64(*fileid);
                bitmap[0] &= ~FATTR4_WORD0_FILEID;
        }
        dprintk("%s: fileid=%Lu\n", __func__, (unsigned long long)*fileid);
        return 0;
}

static int decode_attr_mounted_on_fileid(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *fileid)
{
        __be32 *p;

        *fileid = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_MOUNTED_ON_FILEID - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_MOUNTED_ON_FILEID)) {
                READ_BUF(8);
                READ64(*fileid);
                bitmap[1] &= ~FATTR4_WORD1_MOUNTED_ON_FILEID;
        }
        dprintk("%s: fileid=%Lu\n", __func__, (unsigned long long)*fileid);
        return 0;
}

static int decode_attr_files_avail(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_FILES_AVAIL - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_FILES_AVAIL)) {
                READ_BUF(8);
                READ64(*res);
                bitmap[0] &= ~FATTR4_WORD0_FILES_AVAIL;
        }
        dprintk("%s: files avail=%Lu\n", __func__, (unsigned long long)*res);
        return status;
}

static int decode_attr_files_free(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_FILES_FREE - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_FILES_FREE)) {
                READ_BUF(8);
                READ64(*res);
                bitmap[0] &= ~FATTR4_WORD0_FILES_FREE;
        }
        dprintk("%s: files free=%Lu\n", __func__, (unsigned long long)*res);
        return status;
}

static int decode_attr_files_total(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_FILES_TOTAL - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_FILES_TOTAL)) {
                READ_BUF(8);
                READ64(*res);
                bitmap[0] &= ~FATTR4_WORD0_FILES_TOTAL;
        }
        dprintk("%s: files total=%Lu\n", __func__, (unsigned long long)*res);
        return status;
}

static int decode_pathname(struct xdr_stream *xdr, struct nfs4_pathname *path)
{
        u32 n;
        __be32 *p;
        int status = 0;

        READ_BUF(4);
        READ32(n);
        if (n == 0)
                goto root_path;
        dprintk("path ");
        path->ncomponents = 0;
        while (path->ncomponents < n) {
                struct nfs4_string *component = &path->components[path->ncomponents];
                status = decode_opaque_inline(xdr, &component->len, &component->data);
                if (unlikely(status != 0))
                        goto out_eio;
                if (path->ncomponents != n)
                        dprintk("/");
                dprintk("%s", component->data);
                if (path->ncomponents < NFS4_PATHNAME_MAXCOMPONENTS)
                        path->ncomponents++;
                else {
                        dprintk("cannot parse %d components in path\n", n);
                        goto out_eio;
                }
        }
out:
        dprintk("\n");
        return status;
root_path:
/* a root pathname is sent as a zero component4 */
        path->ncomponents = 1;
        path->components[0].len=0;
        path->components[0].data=NULL;
        dprintk("path /\n");
        goto out;
out_eio:
        dprintk(" status %d", status);
        status = -EIO;
        goto out;
}

static int decode_attr_fs_locations(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs4_fs_locations *res)
{
        int n;
        __be32 *p;
        int status = -EIO;

        if (unlikely(bitmap[0] & (FATTR4_WORD0_FS_LOCATIONS -1U)))
                goto out;
        status = 0;
        if (unlikely(!(bitmap[0] & FATTR4_WORD0_FS_LOCATIONS)))
                goto out;
        dprintk("%s: fsroot ", __func__);
        status = decode_pathname(xdr, &res->fs_path);
        if (unlikely(status != 0))
                goto out;
        READ_BUF(4);
        READ32(n);
        if (n <= 0)
                goto out_eio;
        res->nlocations = 0;
        while (res->nlocations < n) {
                u32 m;
                struct nfs4_fs_location *loc = &res->locations[res->nlocations];

                READ_BUF(4);
                READ32(m);

                loc->nservers = 0;
                dprintk("%s: servers ", __func__);
                while (loc->nservers < m) {
                        struct nfs4_string *server = &loc->servers[loc->nservers];
                        status = decode_opaque_inline(xdr, &server->len, &server->data);
                        if (unlikely(status != 0))
                                goto out_eio;
                        dprintk("%s ", server->data);
                        if (loc->nservers < NFS4_FS_LOCATION_MAXSERVERS)
                                loc->nservers++;
                        else {
                                unsigned int i;
                                dprintk("%s: using first %u of %u servers "
                                        "returned for location %u\n",
                                                __func__,
                                                NFS4_FS_LOCATION_MAXSERVERS,
                                                m, res->nlocations);
                                for (i = loc->nservers; i < m; i++) {
                                        unsigned int len;
                                        char *data;
                                        status = decode_opaque_inline(xdr, &len, &data);
                                        if (unlikely(status != 0))
                                                goto out_eio;
                                }
                        }
                }
                status = decode_pathname(xdr, &loc->rootpath);
                if (unlikely(status != 0))
                        goto out_eio;
                if (res->nlocations < NFS4_FS_LOCATIONS_MAXENTRIES)
                        res->nlocations++;
        }
out:
        dprintk("%s: fs_locations done, error = %d\n", __func__, status);
        return status;
out_eio:
        status = -EIO;
        goto out;
}

static int decode_attr_maxfilesize(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 0;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXFILESIZE - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_MAXFILESIZE)) {
                READ_BUF(8);
                READ64(*res);
                bitmap[0] &= ~FATTR4_WORD0_MAXFILESIZE;
        }
        dprintk("%s: maxfilesize=%Lu\n", __func__, (unsigned long long)*res);
        return status;
}

static int decode_attr_maxlink(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *maxlink)
{
        __be32 *p;
        int status = 0;

        *maxlink = 1;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXLINK - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_MAXLINK)) {
                READ_BUF(4);
                READ32(*maxlink);
                bitmap[0] &= ~FATTR4_WORD0_MAXLINK;
        }
        dprintk("%s: maxlink=%u\n", __func__, *maxlink);
        return status;
}

static int decode_attr_maxname(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *maxname)
{
        __be32 *p;
        int status = 0;

        *maxname = 1024;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXNAME - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_MAXNAME)) {
                READ_BUF(4);
                READ32(*maxname);
                bitmap[0] &= ~FATTR4_WORD0_MAXNAME;
        }
        dprintk("%s: maxname=%u\n", __func__, *maxname);
        return status;
}

static int decode_attr_maxread(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 1024;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXREAD - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_MAXREAD)) {
                uint64_t maxread;
                READ_BUF(8);
                READ64(maxread);
                if (maxread > 0x7FFFFFFF)
                        maxread = 0x7FFFFFFF;
                *res = (uint32_t)maxread;
                bitmap[0] &= ~FATTR4_WORD0_MAXREAD;
        }
        dprintk("%s: maxread=%lu\n", __func__, (unsigned long)*res);
        return status;
}

static int decode_attr_maxwrite(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 1024;
        if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXWRITE - 1U)))
                return -EIO;
        if (likely(bitmap[0] & FATTR4_WORD0_MAXWRITE)) {
                uint64_t maxwrite;
                READ_BUF(8);
                READ64(maxwrite);
                if (maxwrite > 0x7FFFFFFF)
                        maxwrite = 0x7FFFFFFF;
                *res = (uint32_t)maxwrite;
                bitmap[0] &= ~FATTR4_WORD0_MAXWRITE;
        }
        dprintk("%s: maxwrite=%lu\n", __func__, (unsigned long)*res);
        return status;
}

static int decode_attr_mode(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *mode)
{
        __be32 *p;

        *mode = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_MODE - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_MODE)) {
                READ_BUF(4);
                READ32(*mode);
                *mode &= ~S_IFMT;
                bitmap[1] &= ~FATTR4_WORD1_MODE;
        }
        dprintk("%s: file mode=0%o\n", __func__, (unsigned int)*mode);
        return 0;
}

static int decode_attr_nlink(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *nlink)
{
        __be32 *p;

        *nlink = 1;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_NUMLINKS - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_NUMLINKS)) {
                READ_BUF(4);
                READ32(*nlink);
                bitmap[1] &= ~FATTR4_WORD1_NUMLINKS;
        }
        dprintk("%s: nlink=%u\n", __func__, (unsigned int)*nlink);
        return 0;
}

static int decode_attr_owner(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs_client *clp, uint32_t *uid)
{
        uint32_t len;
        __be32 *p;

        *uid = -2;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_OWNER - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_OWNER)) {
                READ_BUF(4);
                READ32(len);
                READ_BUF(len);
                if (len < XDR_MAX_NETOBJ) {
                        if (nfs_map_name_to_uid(clp, (char *)p, len, uid) != 0)
                                dprintk("%s: nfs_map_name_to_uid failed!\n",
                                                __func__);
                } else
                        dprintk("%s: name too long (%u)!\n",
                                        __func__, len);
                bitmap[1] &= ~FATTR4_WORD1_OWNER;
        }
        dprintk("%s: uid=%d\n", __func__, (int)*uid);
        return 0;
}

static int decode_attr_group(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs_client *clp, uint32_t *gid)
{
        uint32_t len;
        __be32 *p;

        *gid = -2;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_OWNER_GROUP - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_OWNER_GROUP)) {
                READ_BUF(4);
                READ32(len);
                READ_BUF(len);
                if (len < XDR_MAX_NETOBJ) {
                        if (nfs_map_group_to_gid(clp, (char *)p, len, gid) != 0)
                                dprintk("%s: nfs_map_group_to_gid failed!\n",
                                                __func__);
                } else
                        dprintk("%s: name too long (%u)!\n",
                                        __func__, len);
                bitmap[1] &= ~FATTR4_WORD1_OWNER_GROUP;
        }
        dprintk("%s: gid=%d\n", __func__, (int)*gid);
        return 0;
}

static int decode_attr_rdev(struct xdr_stream *xdr, uint32_t *bitmap, dev_t *rdev)
{
        uint32_t major = 0, minor = 0;
        __be32 *p;

        *rdev = MKDEV(0,0);
        if (unlikely(bitmap[1] & (FATTR4_WORD1_RAWDEV - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_RAWDEV)) {
                dev_t tmp;

                READ_BUF(8);
                READ32(major);
                READ32(minor);
                tmp = MKDEV(major, minor);
                if (MAJOR(tmp) == major && MINOR(tmp) == minor)
                        *rdev = tmp;
                bitmap[1] &= ~ FATTR4_WORD1_RAWDEV;
        }
        dprintk("%s: rdev=(0x%x:0x%x)\n", __func__, major, minor);
        return 0;
}

static int decode_attr_space_avail(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_SPACE_AVAIL - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_SPACE_AVAIL)) {
                READ_BUF(8);
                READ64(*res);
                bitmap[1] &= ~FATTR4_WORD1_SPACE_AVAIL;
        }
        dprintk("%s: space avail=%Lu\n", __func__, (unsigned long long)*res);
        return status;
}

static int decode_attr_space_free(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_SPACE_FREE - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_SPACE_FREE)) {
                READ_BUF(8);
                READ64(*res);
                bitmap[1] &= ~FATTR4_WORD1_SPACE_FREE;
        }
        dprintk("%s: space free=%Lu\n", __func__, (unsigned long long)*res);
        return status;
}

static int decode_attr_space_total(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
        __be32 *p;
        int status = 0;

        *res = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_SPACE_TOTAL - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_SPACE_TOTAL)) {
                READ_BUF(8);
                READ64(*res);
                bitmap[1] &= ~FATTR4_WORD1_SPACE_TOTAL;
        }
        dprintk("%s: space total=%Lu\n", __func__, (unsigned long long)*res);
        return status;
}

static int decode_attr_space_used(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *used)
{
        __be32 *p;

        *used = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_SPACE_USED - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_SPACE_USED)) {
                READ_BUF(8);
                READ64(*used);
                bitmap[1] &= ~FATTR4_WORD1_SPACE_USED;
        }
        dprintk("%s: space used=%Lu\n", __func__,
                        (unsigned long long)*used);
        return 0;
}

static int decode_attr_time(struct xdr_stream *xdr, struct timespec *time)
{
        __be32 *p;
        uint64_t sec;
        uint32_t nsec;

        READ_BUF(12);
        READ64(sec);
        READ32(nsec);
        time->tv_sec = (time_t)sec;
        time->tv_nsec = (long)nsec;
        return 0;
}

static int decode_attr_time_access(struct xdr_stream *xdr, uint32_t *bitmap, struct timespec *time)
{
        int status = 0;

        time->tv_sec = 0;
        time->tv_nsec = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_TIME_ACCESS - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_TIME_ACCESS)) {
                status = decode_attr_time(xdr, time);
                bitmap[1] &= ~FATTR4_WORD1_TIME_ACCESS;
        }
        dprintk("%s: atime=%ld\n", __func__, (long)time->tv_sec);
        return status;
}

static int decode_attr_time_metadata(struct xdr_stream *xdr, uint32_t *bitmap, struct timespec *time)
{
        int status = 0;

        time->tv_sec = 0;
        time->tv_nsec = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_TIME_METADATA - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_TIME_METADATA)) {
                status = decode_attr_time(xdr, time);
                bitmap[1] &= ~FATTR4_WORD1_TIME_METADATA;
        }
        dprintk("%s: ctime=%ld\n", __func__, (long)time->tv_sec);
        return status;
}

static int decode_attr_time_modify(struct xdr_stream *xdr, uint32_t *bitmap, struct timespec *time)
{
        int status = 0;

        time->tv_sec = 0;
        time->tv_nsec = 0;
        if (unlikely(bitmap[1] & (FATTR4_WORD1_TIME_MODIFY - 1U)))
                return -EIO;
        if (likely(bitmap[1] & FATTR4_WORD1_TIME_MODIFY)) {
                status = decode_attr_time(xdr, time);
                bitmap[1] &= ~FATTR4_WORD1_TIME_MODIFY;
        }
        dprintk("%s: mtime=%ld\n", __func__, (long)time->tv_sec);
        return status;
}

static int verify_attr_len(struct xdr_stream *xdr, __be32 *savep, uint32_t attrlen)
{
        unsigned int attrwords = XDR_QUADLEN(attrlen);
        unsigned int nwords = xdr->p - savep;

        if (unlikely(attrwords != nwords)) {
                dprintk("%s: server returned incorrect attribute length: "
                        "%u %c %u\n",
                                __func__,
                                attrwords << 2,
                                (attrwords < nwords) ? '<' : '>',
                                nwords << 2);
                return -EIO;
        }
        return 0;
}

static int decode_change_info(struct xdr_stream *xdr, struct nfs4_change_info *cinfo)
{
        __be32 *p;

        READ_BUF(20);
        READ32(cinfo->atomic);
        READ64(cinfo->before);
        READ64(cinfo->after);
        return 0;
}

static int decode_access(struct xdr_stream *xdr, struct nfs4_accessres *access)
{
        __be32 *p;
        uint32_t supp, acc;
        int status;

        status = decode_op_hdr(xdr, OP_ACCESS);
        if (status)
                return status;
        READ_BUF(8);
        READ32(supp);
        READ32(acc);
        access->supported = supp;
        access->access = acc;
        return 0;
}