// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
 */
#ifndef __LINUX_FS_NFS_NFS4_2XDR_H
#define __LINUX_FS_NFS_NFS4_2XDR_H

#include "nfs42.h"

/* Not limited by NFS itself, limited by the generic xattr code */
#define nfs4_xattr_name_maxsz   XDR_QUADLEN(XATTR_NAME_MAX)

#define encode_fallocate_maxsz          (encode_stateid_maxsz + \
                                         2 /* offset */ + \
                                         2 /* length */)
#define NFS42_WRITE_RES_SIZE            (1 /* wr_callback_id size */ +\
                                         XDR_QUADLEN(NFS4_STATEID_SIZE) + \
                                         2 /* wr_count */ + \
                                         1 /* wr_committed */ + \
                                         XDR_QUADLEN(NFS4_VERIFIER_SIZE))
#define encode_allocate_maxsz           (op_encode_hdr_maxsz + \
                                         encode_fallocate_maxsz)
#define decode_allocate_maxsz           (op_decode_hdr_maxsz)
#define encode_copy_maxsz               (op_encode_hdr_maxsz +          \
                                         XDR_QUADLEN(NFS4_STATEID_SIZE) + \
                                         XDR_QUADLEN(NFS4_STATEID_SIZE) + \
                                         2 + 2 + 2 + 1 + 1 + 1 +\
                                         1 + /* One cnr_source_server */\
                                         1 + /* nl4_type */ \
                                         1 + XDR_QUADLEN(NFS4_OPAQUE_LIMIT))
#define decode_copy_maxsz               (op_decode_hdr_maxsz + \
                                         NFS42_WRITE_RES_SIZE + \
                                         1 /* cr_consecutive */ + \
                                         1 /* cr_synchronous */)
#define encode_offload_cancel_maxsz     (op_encode_hdr_maxsz + \
                                         XDR_QUADLEN(NFS4_STATEID_SIZE))
#define decode_offload_cancel_maxsz     (op_decode_hdr_maxsz)
#define encode_offload_status_maxsz     (op_encode_hdr_maxsz + \
                                         XDR_QUADLEN(NFS4_STATEID_SIZE))
#define decode_offload_status_maxsz     (op_decode_hdr_maxsz + \
                                         2 /* osr_count */ + \
                                         2 /* osr_complete */)
#define encode_copy_notify_maxsz        (op_encode_hdr_maxsz + \
                                         XDR_QUADLEN(NFS4_STATEID_SIZE) + \
                                         1 + /* nl4_type */ \
                                         1 + XDR_QUADLEN(NFS4_OPAQUE_LIMIT))
#define decode_copy_notify_maxsz        (op_decode_hdr_maxsz + \
                                         3 + /* cnr_lease_time */\
                                         XDR_QUADLEN(NFS4_STATEID_SIZE) + \
                                         1 + /* Support 1 cnr_source_server */\
                                         1 + /* nl4_type */ \
                                         1 + XDR_QUADLEN(NFS4_OPAQUE_LIMIT))
#define encode_deallocate_maxsz         (op_encode_hdr_maxsz + \
                                         encode_fallocate_maxsz)
#define decode_deallocate_maxsz         (op_decode_hdr_maxsz)
#define encode_read_plus_maxsz          (op_encode_hdr_maxsz + \
                                         encode_stateid_maxsz + 3)
#define NFS42_READ_PLUS_DATA_SEGMENT_SIZE \
                                        (1 /* data_content4 */ + \
                                         2 /* data_info4.di_offset */ + \
                                         1 /* data_info4.di_length */)
#define NFS42_READ_PLUS_HOLE_SEGMENT_SIZE \
                                        (1 /* data_content4 */ + \
                                         2 /* data_info4.di_offset */ + \
                                         2 /* data_info4.di_length */)
#define READ_PLUS_SEGMENT_SIZE_DIFF     (NFS42_READ_PLUS_HOLE_SEGMENT_SIZE - \
                                         NFS42_READ_PLUS_DATA_SEGMENT_SIZE)
#define decode_read_plus_maxsz          (op_decode_hdr_maxsz + \
                                         1 /* rpr_eof */ + \
                                         1 /* rpr_contents count */ + \
                                         NFS42_READ_PLUS_HOLE_SEGMENT_SIZE)
#define encode_seek_maxsz               (op_encode_hdr_maxsz + \
                                         encode_stateid_maxsz + \
                                         2 /* offset */ + \
                                         1 /* whence */)
#define decode_seek_maxsz               (op_decode_hdr_maxsz + \
                                         1 /* eof */ + \
                                         1 /* whence */ + \
                                         2 /* offset */ + \
                                         2 /* length */)
#define encode_io_info_maxsz            4
#define encode_layoutstats_maxsz        (op_decode_hdr_maxsz + \
                                        2 /* offset */ + \
                                        2 /* length */ + \
                                        encode_stateid_maxsz + \
                                        encode_io_info_maxsz + \
                                        encode_io_info_maxsz + \
                                        1 /* opaque devaddr4 length */ + \
                                        XDR_QUADLEN(PNFS_LAYOUTSTATS_MAXSIZE))
#define decode_layoutstats_maxsz        (op_decode_hdr_maxsz)
#define encode_device_error_maxsz       (XDR_QUADLEN(NFS4_DEVICEID4_SIZE) + \
                                        1 /* status */ + 1 /* opnum */)
#define encode_layouterror_maxsz        (op_decode_hdr_maxsz + \
                                        2 /* offset */ + \
                                        2 /* length */ + \
                                        encode_stateid_maxsz + \
                                        1 /* Array size */ + \
                                        encode_device_error_maxsz)
#define decode_layouterror_maxsz        (op_decode_hdr_maxsz)
#define encode_clone_maxsz              (encode_stateid_maxsz + \
                                        encode_stateid_maxsz + \
                                        2 /* src offset */ + \
                                        2 /* dst offset */ + \
                                        2 /* count */)
#define decode_clone_maxsz              (op_decode_hdr_maxsz)
#define encode_getxattr_maxsz           (op_encode_hdr_maxsz + 1 + \
                                         nfs4_xattr_name_maxsz)
#define decode_getxattr_maxsz           (op_decode_hdr_maxsz + 1 + pagepad_maxsz)
#define encode_setxattr_maxsz           (op_encode_hdr_maxsz + \
                                         1 + nfs4_xattr_name_maxsz + 1)
#define decode_setxattr_maxsz           (op_decode_hdr_maxsz + decode_change_info_maxsz)
#define encode_listxattrs_maxsz         (op_encode_hdr_maxsz + 2 + 1)
#define decode_listxattrs_maxsz         (op_decode_hdr_maxsz + 2 + 1 + 1 + 1)
#define encode_removexattr_maxsz        (op_encode_hdr_maxsz + 1 + \
                                         nfs4_xattr_name_maxsz)
#define decode_removexattr_maxsz        (op_decode_hdr_maxsz + \
                                         decode_change_info_maxsz)

#define NFS4_enc_allocate_sz            (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_allocate_maxsz + \
                                         encode_getattr_maxsz)
#define NFS4_dec_allocate_sz            (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_allocate_maxsz + \
                                         decode_getattr_maxsz)
#define NFS4_enc_copy_sz                (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_savefh_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_copy_maxsz + \
                                         encode_commit_maxsz)
#define NFS4_dec_copy_sz                (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_savefh_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_copy_maxsz + \
                                         decode_commit_maxsz)
#define NFS4_enc_offload_cancel_sz      (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_offload_cancel_maxsz)
#define NFS4_dec_offload_cancel_sz      (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_offload_cancel_maxsz)
#define NFS4_enc_offload_status_sz      (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_offload_status_maxsz)
#define NFS4_dec_offload_status_sz      (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_offload_status_maxsz)
#define NFS4_enc_copy_notify_sz         (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_copy_notify_maxsz)
#define NFS4_dec_copy_notify_sz         (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_copy_notify_maxsz)
#define NFS4_enc_deallocate_sz          (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_deallocate_maxsz + \
                                         encode_getattr_maxsz)
#define NFS4_dec_deallocate_sz          (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_deallocate_maxsz + \
                                         decode_getattr_maxsz)
#define NFS4_enc_zero_range_sz          (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_deallocate_maxsz + \
                                         encode_allocate_maxsz + \
                                         encode_getattr_maxsz)
#define NFS4_dec_zero_range_sz          (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_deallocate_maxsz + \
                                         decode_allocate_maxsz + \
                                         decode_getattr_maxsz)
#define NFS4_enc_read_plus_sz           (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_read_plus_maxsz)
#define NFS4_dec_read_plus_sz           (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_read_plus_maxsz)
#define NFS4_enc_seek_sz                (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_seek_maxsz)
#define NFS4_dec_seek_sz                (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_seek_maxsz)
#define NFS4_enc_layoutstats_sz         (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         PNFS_LAYOUTSTATS_MAXDEV * encode_layoutstats_maxsz)
#define NFS4_dec_layoutstats_sz         (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         PNFS_LAYOUTSTATS_MAXDEV * decode_layoutstats_maxsz)
#define NFS4_enc_layouterror_sz         (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         NFS42_LAYOUTERROR_MAX * \
                                         encode_layouterror_maxsz)
#define NFS4_dec_layouterror_sz         (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         NFS42_LAYOUTERROR_MAX * \
                                         decode_layouterror_maxsz)
#define NFS4_enc_clone_sz               (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_savefh_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_clone_maxsz + \
                                         encode_getattr_maxsz)
#define NFS4_dec_clone_sz               (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_savefh_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_clone_maxsz + \
                                         decode_getattr_maxsz)
#define NFS4_enc_getxattr_sz            (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_getxattr_maxsz)
#define NFS4_dec_getxattr_sz            (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_getxattr_maxsz)
#define NFS4_enc_setxattr_sz            (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_setxattr_maxsz + \
                                         encode_getattr_maxsz)
#define NFS4_dec_setxattr_sz            (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_setxattr_maxsz + \
                                         decode_getattr_maxsz)
#define NFS4_enc_listxattrs_sz          (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_listxattrs_maxsz)
#define NFS4_dec_listxattrs_sz          (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_listxattrs_maxsz)
#define NFS4_enc_removexattr_sz         (compound_encode_hdr_maxsz + \
                                         encode_sequence_maxsz + \
                                         encode_putfh_maxsz + \
                                         encode_removexattr_maxsz)
#define NFS4_dec_removexattr_sz         (compound_decode_hdr_maxsz + \
                                         decode_sequence_maxsz + \
                                         decode_putfh_maxsz + \
                                         decode_removexattr_maxsz)

/*
 * These values specify the maximum amount of data that is not
 * associated with the extended attribute name or extended
 * attribute list in the SETXATTR, GETXATTR and LISTXATTR
 * respectively.
 */
const u32 nfs42_maxsetxattr_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
                                        compound_encode_hdr_maxsz +
                                        encode_sequence_maxsz +
                                        encode_putfh_maxsz + 1 +
                                        nfs4_xattr_name_maxsz)
                                        * XDR_UNIT);

const u32 nfs42_maxgetxattr_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
                                        compound_decode_hdr_maxsz +
                                        decode_sequence_maxsz +
                                        decode_putfh_maxsz + 1) * XDR_UNIT);

const u32 nfs42_maxlistxattrs_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
                                        compound_decode_hdr_maxsz +
                                        decode_sequence_maxsz +
                                        decode_putfh_maxsz + 3) * XDR_UNIT);

static void encode_fallocate(struct xdr_stream *xdr,
                             const struct nfs42_falloc_args *args)
{
        encode_nfs4_stateid(xdr, &args->falloc_stateid);
        encode_uint64(xdr, args->falloc_offset);
        encode_uint64(xdr, args->falloc_length);
}

static void encode_allocate(struct xdr_stream *xdr,
                            const struct nfs42_falloc_args *args,
                            struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_ALLOCATE, decode_allocate_maxsz, hdr);
        encode_fallocate(xdr, args);
}

static void encode_nl4_server(struct xdr_stream *xdr,
                              const struct nl4_server *ns)
{
        encode_uint32(xdr, ns->nl4_type);
        switch (ns->nl4_type) {
        case NL4_NAME:
        case NL4_URL:
                encode_string(xdr, ns->u.nl4_str_sz, ns->u.nl4_str);
                break;
        case NL4_NETADDR:
                encode_string(xdr, ns->u.nl4_addr.netid_len,
                              ns->u.nl4_addr.netid);
                encode_string(xdr, ns->u.nl4_addr.addr_len,
                              ns->u.nl4_addr.addr);
                break;
        default:
                WARN_ON_ONCE(1);
        }
}

static void encode_copy(struct xdr_stream *xdr,
                        const struct nfs42_copy_args *args,
                        struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_COPY, decode_copy_maxsz, hdr);
        encode_nfs4_stateid(xdr, &args->src_stateid);
        encode_nfs4_stateid(xdr, &args->dst_stateid);

        encode_uint64(xdr, args->src_pos);
        encode_uint64(xdr, args->dst_pos);
        encode_uint64(xdr, args->count);

        encode_uint32(xdr, 1); /* consecutive = true */
        encode_uint32(xdr, args->sync);
        if (args->cp_src == NULL) { /* intra-ssc */
                encode_uint32(xdr, 0); /* no src server list */
                return;
        }
        encode_uint32(xdr, 1); /* supporting 1 server */
        encode_nl4_server(xdr, args->cp_src);
}

static void encode_copy_commit(struct xdr_stream *xdr,
                          const struct nfs42_copy_args *args,
                          struct compound_hdr *hdr)
{
        __be32 *p;

        encode_op_hdr(xdr, OP_COMMIT, decode_commit_maxsz, hdr);
        p = reserve_space(xdr, 12);
        p = xdr_encode_hyper(p, args->dst_pos);
        *p = cpu_to_be32(args->count);
}

static void encode_offload_cancel(struct xdr_stream *xdr,
                                  const struct nfs42_offload_status_args *args,
                                  struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_OFFLOAD_CANCEL, decode_offload_cancel_maxsz, hdr);
        encode_nfs4_stateid(xdr, &args->osa_stateid);
}

static void encode_offload_status(struct xdr_stream *xdr,
                                  const struct nfs42_offload_status_args *args,
                                  struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_OFFLOAD_STATUS, decode_offload_status_maxsz, hdr);
        encode_nfs4_stateid(xdr, &args->osa_stateid);
}

static void encode_copy_notify(struct xdr_stream *xdr,
                               const struct nfs42_copy_notify_args *args,
                               struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_COPY_NOTIFY, decode_copy_notify_maxsz, hdr);
        encode_nfs4_stateid(xdr, &args->cna_src_stateid);
        encode_nl4_server(xdr, &args->cna_dst);
}

static void encode_deallocate(struct xdr_stream *xdr,
                              const struct nfs42_falloc_args *args,
                              struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_DEALLOCATE, decode_deallocate_maxsz, hdr);
        encode_fallocate(xdr, args);
}

static void encode_read_plus(struct xdr_stream *xdr,
                             const struct nfs_pgio_args *args,
                             struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_READ_PLUS, decode_read_plus_maxsz, hdr);
        encode_nfs4_stateid(xdr, &args->stateid);
        encode_uint64(xdr, args->offset);
        encode_uint32(xdr, args->count);
}

static void encode_seek(struct xdr_stream *xdr,
                        const struct nfs42_seek_args *args,
                        struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_SEEK, decode_seek_maxsz, hdr);
        encode_nfs4_stateid(xdr, &args->sa_stateid);
        encode_uint64(xdr, args->sa_offset);
        encode_uint32(xdr, args->sa_what);
}

static void encode_layoutstats(struct xdr_stream *xdr,
                               const struct nfs42_layoutstat_args *args,
                               struct nfs42_layoutstat_devinfo *devinfo,
                               struct compound_hdr *hdr)
{
        __be32 *p;

        encode_op_hdr(xdr, OP_LAYOUTSTATS, decode_layoutstats_maxsz, hdr);
        p = reserve_space(xdr, 8 + 8);
        p = xdr_encode_hyper(p, devinfo->offset);
        p = xdr_encode_hyper(p, devinfo->length);
        encode_nfs4_stateid(xdr, &args->stateid);
        p = reserve_space(xdr, 4*8 + NFS4_DEVICEID4_SIZE + 4);
        p = xdr_encode_hyper(p, devinfo->read_count);
        p = xdr_encode_hyper(p, devinfo->read_bytes);
        p = xdr_encode_hyper(p, devinfo->write_count);
        p = xdr_encode_hyper(p, devinfo->write_bytes);
        p = xdr_encode_opaque_fixed(p, devinfo->dev_id.data,
                        NFS4_DEVICEID4_SIZE);
        /* Encode layoutupdate4 */
        *p++ = cpu_to_be32(devinfo->layout_type);
        if (devinfo->ld_private.ops)
                devinfo->ld_private.ops->encode(xdr, args,
                                &devinfo->ld_private);
        else
                encode_uint32(xdr, 0);
}

static void encode_clone(struct xdr_stream *xdr,
                         const struct nfs42_clone_args *args,
                         struct compound_hdr *hdr)
{
        __be32 *p;

        encode_op_hdr(xdr, OP_CLONE, decode_clone_maxsz, hdr);
        encode_nfs4_stateid(xdr, &args->src_stateid);
        encode_nfs4_stateid(xdr, &args->dst_stateid);
        p = reserve_space(xdr, 3*8);
        p = xdr_encode_hyper(p, args->src_offset);
        p = xdr_encode_hyper(p, args->dst_offset);
        xdr_encode_hyper(p, args->count);
}

static void encode_device_error(struct xdr_stream *xdr,
                                const struct nfs42_device_error *error)
{
        __be32 *p;

        p = reserve_space(xdr, NFS4_DEVICEID4_SIZE + 2*4);
        p = xdr_encode_opaque_fixed(p, error->dev_id.data,
                        NFS4_DEVICEID4_SIZE);
        *p++ = cpu_to_be32(error->status);
        *p = cpu_to_be32(error->opnum);
}

static void encode_layouterror(struct xdr_stream *xdr,
                               const struct nfs42_layout_error *args,
                               struct compound_hdr *hdr)
{
        __be32 *p;

        encode_op_hdr(xdr, OP_LAYOUTERROR, decode_layouterror_maxsz, hdr);
        p = reserve_space(xdr, 8 + 8);
        p = xdr_encode_hyper(p, args->offset);
        p = xdr_encode_hyper(p, args->length);
        encode_nfs4_stateid(xdr, &args->stateid);
        p = reserve_space(xdr, 4);
        *p = cpu_to_be32(1);
        encode_device_error(xdr, &args->errors[0]);
}

static void encode_setxattr(struct xdr_stream *xdr,
                            const struct nfs42_setxattrargs *arg,
                            struct compound_hdr *hdr)
{
        __be32 *p;

        BUILD_BUG_ON(XATTR_CREATE != SETXATTR4_CREATE);
        BUILD_BUG_ON(XATTR_REPLACE != SETXATTR4_REPLACE);

        encode_op_hdr(xdr, OP_SETXATTR, decode_setxattr_maxsz, hdr);
        p = reserve_space(xdr, 4);
        *p = cpu_to_be32(arg->xattr_flags);
        encode_string(xdr, strlen(arg->xattr_name), arg->xattr_name);
        p = reserve_space(xdr, 4);
        *p = cpu_to_be32(arg->xattr_len);
        if (arg->xattr_len)
                xdr_write_pages(xdr, arg->xattr_pages, 0, arg->xattr_len);
}

static void encode_getxattr(struct xdr_stream *xdr, const char *name,
                            struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_GETXATTR, decode_getxattr_maxsz, hdr);
        encode_string(xdr, strlen(name), name);
}

static void encode_removexattr(struct xdr_stream *xdr, const char *name,
                               struct compound_hdr *hdr)
{
        encode_op_hdr(xdr, OP_REMOVEXATTR, decode_removexattr_maxsz, hdr);
        encode_string(xdr, strlen(name), name);
}

static void encode_listxattrs(struct xdr_stream *xdr,
                             const struct nfs42_listxattrsargs *arg,
                             struct compound_hdr *hdr)
{
        __be32 *p;

        encode_op_hdr(xdr, OP_LISTXATTRS, decode_listxattrs_maxsz, hdr);

        p = reserve_space(xdr, 12);
        if (unlikely(!p))
                return;

        p = xdr_encode_hyper(p, arg->cookie);
        /*
         * RFC 8276 says to specify the full max length of the LISTXATTRS
         * XDR reply. Count is set to the XDR length of the names array
         * plus the EOF marker. So, add the cookie and the names count.
         */
        *p = cpu_to_be32(arg->count + 8 + 4);
}

/*
 * Encode ALLOCATE request
 */
static void nfs4_xdr_enc_allocate(struct rpc_rqst *req,
                                  struct xdr_stream *xdr,
                                  const void *data)
{
        const struct nfs42_falloc_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->falloc_fh, &hdr);
        encode_allocate(xdr, args, &hdr);
        encode_getfattr(xdr, args->falloc_bitmask, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode COPY request
 */
static void nfs4_xdr_enc_copy(struct rpc_rqst *req,
                              struct xdr_stream *xdr,
                              const void *data)
{
        const struct nfs42_copy_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->src_fh, &hdr);
        encode_savefh(xdr, &hdr);
        encode_putfh(xdr, args->dst_fh, &hdr);
        encode_copy(xdr, args, &hdr);
        if (args->sync)
                encode_copy_commit(xdr, args, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode OFFLOAD_CANCEL request
 */
static void nfs4_xdr_enc_offload_cancel(struct rpc_rqst *req,
                                        struct xdr_stream *xdr,
                                        const void *data)
{
        const struct nfs42_offload_status_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->osa_seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->osa_seq_args, &hdr);
        encode_putfh(xdr, args->osa_src_fh, &hdr);
        encode_offload_cancel(xdr, args, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode OFFLOAD_STATUS request
 */
static void nfs4_xdr_enc_offload_status(struct rpc_rqst *req,
                                        struct xdr_stream *xdr,
                                        const void *data)
{
        const struct nfs42_offload_status_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->osa_seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->osa_seq_args, &hdr);
        encode_putfh(xdr, args->osa_src_fh, &hdr);
        encode_offload_status(xdr, args, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode COPY_NOTIFY request
 */
static void nfs4_xdr_enc_copy_notify(struct rpc_rqst *req,
                                     struct xdr_stream *xdr,
                                     const void *data)
{
        const struct nfs42_copy_notify_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->cna_seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->cna_seq_args, &hdr);
        encode_putfh(xdr, args->cna_src_fh, &hdr);
        encode_copy_notify(xdr, args, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode DEALLOCATE request
 */
static void nfs4_xdr_enc_deallocate(struct rpc_rqst *req,
                                    struct xdr_stream *xdr,
                                    const void *data)
{
        const struct nfs42_falloc_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->falloc_fh, &hdr);
        encode_deallocate(xdr, args, &hdr);
        encode_getfattr(xdr, args->falloc_bitmask, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode ZERO_RANGE request
 */
static void nfs4_xdr_enc_zero_range(struct rpc_rqst *req,
                                    struct xdr_stream *xdr,
                                    const void *data)
{
        const struct nfs42_falloc_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->falloc_fh, &hdr);
        encode_deallocate(xdr, args, &hdr);
        encode_allocate(xdr, args, &hdr);
        encode_getfattr(xdr, args->falloc_bitmask, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode READ_PLUS request
 */
static void nfs4_xdr_enc_read_plus(struct rpc_rqst *req,
                                   struct xdr_stream *xdr,
                                   const void *data)
{
        const struct nfs_pgio_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->fh, &hdr);
        encode_read_plus(xdr, args, &hdr);

        rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->count,
                                hdr.replen - READ_PLUS_SEGMENT_SIZE_DIFF);
        encode_nops(&hdr);
}

/*
 * Encode SEEK request
 */
static void nfs4_xdr_enc_seek(struct rpc_rqst *req,
                              struct xdr_stream *xdr,
                              const void *data)
{
        const struct nfs42_seek_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->sa_fh, &hdr);
        encode_seek(xdr, args, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode LAYOUTSTATS request
 */
static void nfs4_xdr_enc_layoutstats(struct rpc_rqst *req,
                                     struct xdr_stream *xdr,
                                     const void *data)
{
        const struct nfs42_layoutstat_args *args = data;
        int i;

        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->fh, &hdr);
        WARN_ON(args->num_dev > PNFS_LAYOUTSTATS_MAXDEV);
        for (i = 0; i < args->num_dev; i++)
                encode_layoutstats(xdr, args, &args->devinfo[i], &hdr);
        encode_nops(&hdr);
}

/*
 * Encode CLONE request
 */
static void nfs4_xdr_enc_clone(struct rpc_rqst *req,
                               struct xdr_stream *xdr,
                               const void *data)
{
        const struct nfs42_clone_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->src_fh, &hdr);
        encode_savefh(xdr, &hdr);
        encode_putfh(xdr, args->dst_fh, &hdr);
        encode_clone(xdr, args, &hdr);
        encode_getfattr(xdr, args->dst_bitmask, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode LAYOUTERROR request
 */
static void nfs4_xdr_enc_layouterror(struct rpc_rqst *req,
                                     struct xdr_stream *xdr,
                                     const void *data)
{
        const struct nfs42_layouterror_args *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };
        int i;

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, NFS_FH(args->inode), &hdr);
        for (i = 0; i < args->num_errors; i++)
                encode_layouterror(xdr, &args->errors[i], &hdr);
        encode_nops(&hdr);
}

/*
 * Encode SETXATTR request
 */
static void nfs4_xdr_enc_setxattr(struct rpc_rqst *req, struct xdr_stream *xdr,
                                  const void *data)
{
        const struct nfs42_setxattrargs *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->fh, &hdr);
        encode_setxattr(xdr, args, &hdr);
        encode_getfattr(xdr, args->bitmask, &hdr);
        encode_nops(&hdr);
}

/*
 * Encode GETXATTR request
 */
static void nfs4_xdr_enc_getxattr(struct rpc_rqst *req, struct xdr_stream *xdr,
                                  const void *data)
{
        const struct nfs42_getxattrargs *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };
        uint32_t replen;

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->fh, &hdr);
        replen = hdr.replen + op_decode_hdr_maxsz + 1;
        encode_getxattr(xdr, args->xattr_name, &hdr);

        rpc_prepare_reply_pages(req, args->xattr_pages, 0, args->xattr_len,
                                replen);

        encode_nops(&hdr);
}

/*
 * Encode LISTXATTR request
 */
static void nfs4_xdr_enc_listxattrs(struct rpc_rqst *req,
                                    struct xdr_stream *xdr, const void *data)
{
        const struct nfs42_listxattrsargs *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };
        uint32_t replen;

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->fh, &hdr);
        replen = hdr.replen + op_decode_hdr_maxsz + 2 + 1;
        encode_listxattrs(xdr, args, &hdr);

        rpc_prepare_reply_pages(req, args->xattr_pages, 0, args->count, replen);

        encode_nops(&hdr);
}

/*
 * Encode REMOVEXATTR request
 */
static void nfs4_xdr_enc_removexattr(struct rpc_rqst *req,
                                     struct xdr_stream *xdr, const void *data)
{
        const struct nfs42_removexattrargs *args = data;
        struct compound_hdr hdr = {
                .minorversion = nfs4_xdr_minorversion(&args->seq_args),
        };

        encode_compound_hdr(xdr, req, &hdr);
        encode_sequence(xdr, &args->seq_args, &hdr);
        encode_putfh(xdr, args->fh, &hdr);
        encode_removexattr(xdr, args->xattr_name, &hdr);
        encode_nops(&hdr);
}

static int decode_allocate(struct xdr_stream *xdr, struct nfs42_falloc_res *res)
{
        return decode_op_hdr(xdr, OP_ALLOCATE);
}

static int decode_write_response(struct xdr_stream *xdr,
                                 struct nfs42_write_res *res)
{
        __be32 *p;
        int status, count;

        p = xdr_inline_decode(xdr, 4);
        if (unlikely(!p))
                return -EIO;
        count = be32_to_cpup(p);
        if (count > 1)
                return -EREMOTEIO;
        else if (count == 1) {
                status = decode_opaque_fixed(xdr, &res->stateid,
                                NFS4_STATEID_SIZE);
                if (unlikely(status))
                        return -EIO;
        }
        p = xdr_inline_decode(xdr, 8 + 4);
        if (unlikely(!p))
                return -EIO;
        p = xdr_decode_hyper(p, &res->count);
        res->verifier.committed = be32_to_cpup(p);
        return decode_verifier(xdr, &res->verifier.verifier);
}

static int decode_nl4_server(struct xdr_stream *xdr, struct nl4_server *ns)
{
        struct nfs42_netaddr *naddr;
        uint32_t dummy;
        char *dummy_str;
        __be32 *p;
        int status;

        /* nl_type */
        p = xdr_inline_decode(xdr, 4);
        if (unlikely(!p))
                return -EIO;
        ns->nl4_type = be32_to_cpup(p);
        switch (ns->nl4_type) {
        case NL4_NAME:
        case NL4_URL:
                status = decode_opaque_inline(xdr, &dummy, &dummy_str);
                if (unlikely(status))
                        return status;
                if (unlikely(dummy > NFS4_OPAQUE_LIMIT))
                        return -EIO;
                memcpy(&ns->u.nl4_str, dummy_str, dummy);
                ns->u.nl4_str_sz = dummy;
                break;
        case NL4_NETADDR:
                naddr = &ns->u.nl4_addr;

                /* netid string */
                status = decode_opaque_inline(xdr, &dummy, &dummy_str);
                if (unlikely(status))
                        return status;
                if (unlikely(dummy > RPCBIND_MAXNETIDLEN))
                        return -EIO;
                naddr->netid_len = dummy;
                memcpy(naddr->netid, dummy_str, naddr->netid_len);

                /* uaddr string */
                status = decode_opaque_inline(xdr, &dummy, &dummy_str);
                if (unlikely(status))
                        return status;
                if (unlikely(dummy > RPCBIND_MAXUADDRLEN))
                        return -EIO;
                naddr->addr_len = dummy;
                memcpy(naddr->addr, dummy_str, naddr->addr_len);
                break;
        default:
                WARN_ON_ONCE(1);
                return -EIO;
        }
        return 0;
}

static int decode_copy_requirements(struct xdr_stream *xdr,
                                    struct nfs42_copy_res *res) {
        __be32 *p;

        p = xdr_inline_decode(xdr, 4 + 4);
        if (unlikely(!p))
                return -EIO;

        res->consecutive = be32_to_cpup(p++);
        res->synchronous = be32_to_cpup(p++);
        return 0;
}

static int decode_copy(struct xdr_stream *xdr, struct nfs42_copy_res *res)
{
        int status;

        status = decode_op_hdr(xdr, OP_COPY);
        if (status == NFS4ERR_OFFLOAD_NO_REQS) {
                status = decode_copy_requirements(xdr, res);
                if (status)
                        return status;
                return NFS4ERR_OFFLOAD_NO_REQS;
        } else if (status)
                return status;

        status = decode_write_response(xdr, &res->write_res);
        if (status)
                return status;

        return decode_copy_requirements(xdr, res);
}

static int decode_offload_cancel(struct xdr_stream *xdr,
                                 struct nfs42_offload_status_res *res)
{
        return decode_op_hdr(xdr, OP_OFFLOAD_CANCEL);
}

static int decode_offload_status(struct xdr_stream *xdr,
                                 struct nfs42_offload_status_res *res)
{
        ssize_t result;
        int status;

        status = decode_op_hdr(xdr, OP_OFFLOAD_STATUS);
        if (status)
                return status;
        /* osr_count */
        if (xdr_stream_decode_u64(xdr, &res->osr_count) < 0)
                return -EIO;
        /* osr_complete<1> */
        result = xdr_stream_decode_uint32_array(xdr, &res->osr_complete, 1);
        if (result < 0)
                return -EIO;
        res->complete_count = result;
        return 0;
}

static int decode_copy_notify(struct xdr_stream *xdr,
                              struct nfs42_copy_notify_res *res)
{
        __be32 *p;
        int status, count;

        status = decode_op_hdr(xdr, OP_COPY_NOTIFY);
        if (status)
                return status;
        /* cnr_lease_time */
        p = xdr_inline_decode(xdr, 12);
        if (unlikely(!p))
                return -EIO;
        p = xdr_decode_hyper(p, &res->cnr_lease_time.seconds);
        res->cnr_lease_time.nseconds = be32_to_cpup(p);

        status = decode_opaque_fixed(xdr, &res->cnr_stateid, NFS4_STATEID_SIZE);
        if (unlikely(status))
                return -EIO;

        /* number of source addresses */
        p = xdr_inline_decode(xdr, 4);
        if (unlikely(!p))
                return -EIO;

        count = be32_to_cpup(p);
        if (count > 1)
                pr_warn("NFS: %s: nsvr %d > Supported. Use first servers\n",
                         __func__, count);

        status = decode_nl4_server(xdr, &res->cnr_src);
        if (unlikely(status))
                return -EIO;
        return 0;
}

static int decode_deallocate(struct xdr_stream *xdr, struct nfs42_falloc_res *res)
{
        return decode_op_hdr(xdr, OP_DEALLOCATE);
}

struct read_plus_segment {
        enum data_content4 type;
        uint64_t offset;
        union {
                struct {
                        uint64_t length;
                } hole;

                struct {
                        uint32_t length;
                        unsigned int from;
                } data;
        };
};

static inline uint64_t read_plus_segment_length(struct read_plus_segment *seg)
{
        return seg->type == NFS4_CONTENT_DATA ? seg->data.length : seg->hole.length;
}

static int decode_read_plus_segment(struct xdr_stream *xdr,
                                    struct read_plus_segment *seg)
{
        __be32 *p;

        p = xdr_inline_decode(xdr, 4);
        if (!p)
                return -EIO;
        seg->type = be32_to_cpup(p++);

        p = xdr_inline_decode(xdr, seg->type == NFS4_CONTENT_DATA ? 12 : 16);
        if (!p)
                return -EIO;
        p = xdr_decode_hyper(p, &seg->offset);

        if (seg->type == NFS4_CONTENT_DATA) {
                struct xdr_buf buf;
                uint32_t len = be32_to_cpup(p);

                seg->data.length = len;
                seg->data.from = xdr_stream_pos(xdr);

                if (!xdr_stream_subsegment(xdr, &buf, xdr_align_size(len)))
                        return -EIO;
        } else if (seg->type == NFS4_CONTENT_HOLE) {
                xdr_decode_hyper(p, &seg->hole.length);
        } else
                return -EINVAL;
        return 0;
}

static int process_read_plus_segment(struct xdr_stream *xdr,
                                     struct nfs_pgio_args *args,
                                     struct nfs_pgio_res *res,
                                     struct read_plus_segment *seg)
{
        unsigned long offset = seg->offset;
        unsigned long length = read_plus_segment_length(seg);
        unsigned int bufpos;

        if (offset + length < args->offset)
                return 0;
        else if (offset > args->offset + args->count) {
                res->eof = 0;
                return 0;
        } else if (offset < args->offset) {
                length -= (args->offset - offset);
                offset = args->offset;
        } else if (offset + length > args->offset + args->count) {
                length = (args->offset + args->count) - offset;
                res->eof = 0;
        }

        bufpos = xdr->buf->head[0].iov_len + (offset - args->offset);
        if (seg->type == NFS4_CONTENT_HOLE)
                return xdr_stream_zero(xdr, bufpos, length);
        else
                return xdr_stream_move_subsegment(xdr, seg->data.from, bufpos, length);
}

static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
{
        struct nfs_pgio_header *hdr =
                container_of(res, struct nfs_pgio_header, res);
        struct nfs_pgio_args *args = &hdr->args;
        uint32_t segments;
        struct read_plus_segment *segs;
        int status, i;
        __be32 *p;

        status = decode_op_hdr(xdr, OP_READ_PLUS);
        if (status)
                return status;

        p = xdr_inline_decode(xdr, 4 + 4);
        if (unlikely(!p))
                return -EIO;

        res->count = 0;
        res->eof = be32_to_cpup(p++);
        segments = be32_to_cpup(p++);
        if (segments == 0)
                return 0;

        segs = kmalloc_objs(*segs, segments);
        if (!segs)
                return -ENOMEM;

        for (i = 0; i < segments; i++) {
                status = decode_read_plus_segment(xdr, &segs[i]);
                if (status < 0)
                        goto out;
        }

        xdr_set_pagelen(xdr, xdr_align_size(args->count));
        for (i = segments; i > 0; i--)
                res->count += process_read_plus_segment(xdr, args, res, &segs[i-1]);
        status = 0;

out:
        kfree(segs);
        return status;
}

static int decode_seek(struct xdr_stream *xdr, struct nfs42_seek_res *res)
{
        int status;
        __be32 *p;

        status = decode_op_hdr(xdr, OP_SEEK);
        if (status)
                return status;

        p = xdr_inline_decode(xdr, 4 + 8);
        if (unlikely(!p))
                return -EIO;

        res->sr_eof = be32_to_cpup(p++);
        p = xdr_decode_hyper(p, &res->sr_offset);
        return 0;
}

static int decode_layoutstats(struct xdr_stream *xdr)
{
        return decode_op_hdr(xdr, OP_LAYOUTSTATS);
}

static int decode_clone(struct xdr_stream *xdr)
{
        return decode_op_hdr(xdr, OP_CLONE);
}

static int decode_layouterror(struct xdr_stream *xdr)
{
        return decode_op_hdr(xdr, OP_LAYOUTERROR);
}

static int decode_setxattr(struct xdr_stream *xdr,
                           struct nfs4_change_info *cinfo)
{
        int status;

        status = decode_op_hdr(xdr, OP_SETXATTR);
        if (status)
                goto out;
        status = decode_change_info(xdr, cinfo);
out:
        return status;
}

static int decode_getxattr(struct xdr_stream *xdr,
                           struct nfs42_getxattrres *res,
                           struct rpc_rqst *req)
{
        int status;
        __be32 *p;
        u32 len, rdlen;

        status = decode_op_hdr(xdr, OP_GETXATTR);
        if (status)
                return status;

        p = xdr_inline_decode(xdr, 4);
        if (unlikely(!p))
                return -EIO;

        len = be32_to_cpup(p);

        /*
         * Only check against the page length here. The actual
         * requested length may be smaller, but that is only
         * checked against after possibly caching a valid reply.
         */
        if (len > req->rq_rcv_buf.page_len)
                return -ERANGE;

        res->xattr_len = len;

        if (len > 0) {
                rdlen = xdr_read_pages(xdr, len);
                if (rdlen < len)
                        return -EIO;
        }

        return 0;
}

static int decode_removexattr(struct xdr_stream *xdr,
                           struct nfs4_change_info *cinfo)
{
        int status;

        status = decode_op_hdr(xdr, OP_REMOVEXATTR);
        if (status)
                goto out;

        status = decode_change_info(xdr, cinfo);
out:
        return status;
}

static int decode_listxattrs(struct xdr_stream *xdr,
                            struct nfs42_listxattrsres *res)
{
        int status;
        __be32 *p;
        u32 count, len, ulen;
        size_t left, copied;
        char *buf;

        status = decode_op_hdr(xdr, OP_LISTXATTRS);
        if (status) {
                /*
                 * Special case: for LISTXATTRS, NFS4ERR_TOOSMALL
                 * should be translated to ERANGE.
                 */
                if (status == -ETOOSMALL)
                        status = -ERANGE;
                /*
                 * Special case: for LISTXATTRS, NFS4ERR_NOXATTR
                 * should be translated to success with zero-length reply.
                 */
                if (status == -ENODATA) {
                        res->eof = true;
                        status = 0;
                }
                goto out;
        }

        p = xdr_inline_decode(xdr, 8);
        if (unlikely(!p))
                return -EIO;

        xdr_decode_hyper(p, &res->cookie);

        p = xdr_inline_decode(xdr, 4);
        if (unlikely(!p))
                return -EIO;

        left = res->xattr_len;
        buf = res->xattr_buf;

        count = be32_to_cpup(p);
        copied = 0;

        /*
         * We have asked for enough room to encode the maximum number
         * of possible attribute names, so everything should fit.
         *
         * But, don't rely on that assumption. Just decode entries
         * until they don't fit anymore, just in case the server did
         * something odd.
         */
        while (count--) {
                p = xdr_inline_decode(xdr, 4);
                if (unlikely(!p))
                        return -EIO;

                len = be32_to_cpup(p);
                if (len > (XATTR_NAME_MAX - XATTR_USER_PREFIX_LEN)) {
                        status = -ERANGE;
                        goto out;
                }

                p = xdr_inline_decode(xdr, len);
                if (unlikely(!p))
                        return -EIO;

                ulen = len + XATTR_USER_PREFIX_LEN + 1;
                if (buf) {
                        if (ulen > left) {
                                status = -ERANGE;
                                goto out;
                        }

                        memcpy(buf, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
                        memcpy(buf + XATTR_USER_PREFIX_LEN, p, len);

                        buf[ulen - 1] = 0;
                        buf += ulen;
                        left -= ulen;
                }
                copied += ulen;
        }

        p = xdr_inline_decode(xdr, 4);
        if (unlikely(!p))
                return -EIO;

        res->eof = be32_to_cpup(p);
        res->copied = copied;

out:
        if (status == -ERANGE && res->xattr_len == XATTR_LIST_MAX)
                status = -E2BIG;

        return status;
}

/*
 * Decode ALLOCATE request
 */
static int nfs4_xdr_dec_allocate(struct rpc_rqst *rqstp,
                                 struct xdr_stream *xdr,
                                 void *data)
{
        struct nfs42_falloc_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_allocate(xdr, res);
        if (status)
                goto out;
        decode_getfattr(xdr, res->falloc_fattr, res->falloc_server);
out:
        return status;
}

/*
 * Decode COPY response
 */
static int nfs4_xdr_dec_copy(struct rpc_rqst *rqstp,
                             struct xdr_stream *xdr,
                             void *data)
{
        struct nfs42_copy_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_savefh(xdr);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_copy(xdr, res);
        if (status)
                goto out;
        if (res->commit_res.verf)
                status = decode_commit(xdr, &res->commit_res);
out:
        return status;
}

/*
 * Decode OFFLOAD_CANCEL response
 */
static int nfs4_xdr_dec_offload_cancel(struct rpc_rqst *rqstp,
                                       struct xdr_stream *xdr,
                                       void *data)
{
        struct nfs42_offload_status_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->osr_seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_offload_cancel(xdr, res);

out:
        return status;
}

/*
 * Decode OFFLOAD_STATUS response
 */
static int nfs4_xdr_dec_offload_status(struct rpc_rqst *rqstp,
                                       struct xdr_stream *xdr,
                                       void *data)
{
        struct nfs42_offload_status_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->osr_seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_offload_status(xdr, res);

out:
        return status;
}

/*
 * Decode COPY_NOTIFY response
 */
static int nfs4_xdr_dec_copy_notify(struct rpc_rqst *rqstp,
                                    struct xdr_stream *xdr,
                                    void *data)
{
        struct nfs42_copy_notify_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->cnr_seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_copy_notify(xdr, res);

out:
        return status;
}

/*
 * Decode DEALLOCATE request
 */
static int nfs4_xdr_dec_deallocate(struct rpc_rqst *rqstp,
                                   struct xdr_stream *xdr,
                                   void *data)
{
        struct nfs42_falloc_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_deallocate(xdr, res);
        if (status)
                goto out;
        decode_getfattr(xdr, res->falloc_fattr, res->falloc_server);
out:
        return status;
}

/*
 * Decode ZERO_RANGE request
 */
static int nfs4_xdr_dec_zero_range(struct rpc_rqst *rqstp,
                                   struct xdr_stream *xdr,
                                   void *data)
{
        struct nfs42_falloc_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_deallocate(xdr, res);
        if (status)
                goto out;
        status = decode_allocate(xdr, res);
        if (status)
                goto out;
        decode_getfattr(xdr, res->falloc_fattr, res->falloc_server);
out:
        return status;
}

/*
 * Decode READ_PLUS request
 */
static int nfs4_xdr_dec_read_plus(struct rpc_rqst *rqstp,
                                  struct xdr_stream *xdr,
                                  void *data)
{
        struct nfs_pgio_res *res = data;
        struct compound_hdr hdr;
        int status;

        xdr_set_scratch_buffer(xdr, res->scratch, READ_PLUS_SCRATCH_SIZE);

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_read_plus(xdr, res);
        if (!status)
                status = res->count;
out:
        return status;
}

/*
 * Decode SEEK request
 */
static int nfs4_xdr_dec_seek(struct rpc_rqst *rqstp,
                             struct xdr_stream *xdr,
                             void *data)
{
        struct nfs42_seek_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_seek(xdr, res);
out:
        return status;
}

/*
 * Decode LAYOUTSTATS request
 */
static int nfs4_xdr_dec_layoutstats(struct rpc_rqst *rqstp,
                                    struct xdr_stream *xdr,
                                    void *data)
{
        struct nfs42_layoutstat_res *res = data;
        struct compound_hdr hdr;
        int status, i;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        WARN_ON(res->num_dev > PNFS_LAYOUTSTATS_MAXDEV);
        for (i = 0; i < res->num_dev; i++) {
                status = decode_layoutstats(xdr);
                if (status)
                        goto out;
        }
out:
        res->rpc_status = status;
        return status;
}

/*
 * Decode CLONE request
 */
static int nfs4_xdr_dec_clone(struct rpc_rqst *rqstp,
                              struct xdr_stream *xdr,
                              void *data)
{
        struct nfs42_clone_res *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_savefh(xdr);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_clone(xdr);
        if (status)
                goto out;
        decode_getfattr(xdr, res->dst_fattr, res->server);
out:
        res->rpc_status = status;
        return status;
}

/*
 * Decode LAYOUTERROR request
 */
static int nfs4_xdr_dec_layouterror(struct rpc_rqst *rqstp,
                                    struct xdr_stream *xdr,
                                    void *data)
{
        struct nfs42_layouterror_res *res = data;
        struct compound_hdr hdr;
        int status, i;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);

        for (i = 0; i < res->num_errors && status == 0; i++)
                status = decode_layouterror(xdr);
out:
        res->rpc_status = status;
        return status;
}

/*
 * Decode SETXATTR request
 */
static int nfs4_xdr_dec_setxattr(struct rpc_rqst *req, struct xdr_stream *xdr,
                                 void *data)
{
        struct nfs42_setxattrres *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, req);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_setxattr(xdr, &res->cinfo);
        if (status)
                goto out;
        status = decode_getfattr(xdr, res->fattr, res->server);
out:
        return status;
}

/*
 * Decode GETXATTR request
 */
static int nfs4_xdr_dec_getxattr(struct rpc_rqst *rqstp,
                                 struct xdr_stream *xdr, void *data)
{
        struct nfs42_getxattrres *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_getxattr(xdr, res, rqstp);
out:
        return status;
}

/*
 * Decode LISTXATTR request
 */
static int nfs4_xdr_dec_listxattrs(struct rpc_rqst *rqstp,
                                   struct xdr_stream *xdr, void *data)
{
        struct nfs42_listxattrsres *res = data;
        struct compound_hdr hdr;
        int status;

        xdr_set_scratch_folio(xdr, res->scratch);

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, rqstp);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;
        status = decode_listxattrs(xdr, res);
out:
        return status;
}

/*
 * Decode REMOVEXATTR request
 */
static int nfs4_xdr_dec_removexattr(struct rpc_rqst *req,
                                    struct xdr_stream *xdr, void *data)
{
        struct nfs42_removexattrres *res = data;
        struct compound_hdr hdr;
        int status;

        status = decode_compound_hdr(xdr, &hdr);
        if (status)
                goto out;
        status = decode_sequence(xdr, &res->seq_res, req);
        if (status)
                goto out;
        status = decode_putfh(xdr);
        if (status)
                goto out;

        status = decode_removexattr(xdr, &res->cinfo);
out:
        return status;
}
#endif /* __LINUX_FS_NFS_NFS4_2XDR_H */