LXR linux/include/linux/sunrpc/xdr.h

   1/*
   2 * include/linux/sunrpc/xdr.h
   3 *
   4 * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
   5 */
   6
   7#ifndef _SUNRPC_XDR_H_
   8#define _SUNRPC_XDR_H_
   9
  10#ifdef __KERNEL__
  11
  12#include <linux/uio.h>
  13#include <asm/byteorder.h>
  14#include <linux/scatterlist.h>
  15
  16/*
  17 * Buffer adjustment
  18 */
  19#define XDR_QUADLEN(l)          (((l) + 3) >> 2)
  20
  21/*
  22 * Generic opaque `network object.' At the kernel level, this type
  23 * is used only by lockd.
  24 */
  25#define XDR_MAX_NETOBJ          1024
  26struct xdr_netobj {
  27        unsigned int            len;
  28        u8 *                    data;
  29};
  30
  31/*
  32 * This is the generic XDR function. rqstp is either a rpc_rqst (client
  33 * side) or svc_rqst pointer (server side).
  34 * Encode functions always assume there's enough room in the buffer.
  35 */
  36typedef int     (*kxdrproc_t)(void *rqstp, __be32 *data, void *obj);
  37
  38/*
  39 * Basic structure for transmission/reception of a client XDR message.
  40 * Features a header (for a linear buffer containing RPC headers
  41 * and the data payload for short messages), and then an array of
  42 * pages.
  43 * The tail iovec allows you to append data after the page array. Its
  44 * main interest is for appending padding to the pages in order to
  45 * satisfy the int_32-alignment requirements in RFC1832.
  46 *
  47 * For the future, we might want to string several of these together
  48 * in a list if anybody wants to make use of NFSv4 COMPOUND
  49 * operations and/or has a need for scatter/gather involving pages.
  50 */
  51struct xdr_buf {
  52        struct kvec     head[1],        /* RPC header + non-page data */
  53                        tail[1];        /* Appended after page data */
  54
  55        struct page **  pages;          /* Array of contiguous pages */
  56        unsigned int    page_base,      /* Start of page data */
  57                        page_len,       /* Length of page data */
  58                        flags;          /* Flags for data disposition */
  59#define XDRBUF_READ             0x01            /* target of file read */
  60#define XDRBUF_WRITE            0x02            /* source of file write */
  61
  62        unsigned int    buflen,         /* Total length of storage buffer */
  63                        len;            /* Length of XDR encoded message */
  64
  65};
  66
  67/*
  68 * pre-xdr'ed macros.
  69 */
  70
  71#define xdr_zero        cpu_to_be32(0)
  72#define xdr_one         cpu_to_be32(1)
  73#define xdr_two         cpu_to_be32(2)
  74
  75#define rpc_success             cpu_to_be32(RPC_SUCCESS)
  76#define rpc_prog_unavail        cpu_to_be32(RPC_PROG_UNAVAIL)
  77#define rpc_prog_mismatch       cpu_to_be32(RPC_PROG_MISMATCH)
  78#define rpc_proc_unavail        cpu_to_be32(RPC_PROC_UNAVAIL)
  79#define rpc_garbage_args        cpu_to_be32(RPC_GARBAGE_ARGS)
  80#define rpc_system_err          cpu_to_be32(RPC_SYSTEM_ERR)
  81#define rpc_drop_reply          cpu_to_be32(RPC_DROP_REPLY)
  82
  83#define rpc_auth_ok             cpu_to_be32(RPC_AUTH_OK)
  84#define rpc_autherr_badcred     cpu_to_be32(RPC_AUTH_BADCRED)
  85#define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
  86#define rpc_autherr_badverf     cpu_to_be32(RPC_AUTH_BADVERF)
  87#define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
  88#define rpc_autherr_tooweak     cpu_to_be32(RPC_AUTH_TOOWEAK)
  89#define rpcsec_gsserr_credproblem       cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
  90#define rpcsec_gsserr_ctxproblem        cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
  91#define rpc_autherr_oldseqnum   cpu_to_be32(101)
  92
  93/*
  94 * Miscellaneous XDR helper functions
  95 */
  96__be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
  97__be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
  98__be32 *xdr_encode_string(__be32 *p, const char *s);
  99__be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
 100                        unsigned int maxlen);
 101__be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
 102__be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
 103
 104void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
 105                         unsigned int);
 106void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 107                         struct page **, unsigned int, unsigned int);
 108
 109static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
 110{
 111        return xdr_encode_opaque(p, s, len);
 112}
 113
 114/*
 115 * Decode 64bit quantities (NFSv3 support)
 116 */
 117static inline __be32 *
 118xdr_encode_hyper(__be32 *p, __u64 val)
 119{
 120        *p++ = htonl(val >> 32);
 121        *p++ = htonl(val & 0xFFFFFFFF);
 122        return p;
 123}
 124
 125static inline __be32 *
 126xdr_decode_hyper(__be32 *p, __u64 *valp)
 127{
 128        *valp  = ((__u64) ntohl(*p++)) << 32;
 129        *valp |= ntohl(*p++);
 130        return p;
 131}
 132
 133/*
 134 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
 135 */
 136static inline int
 137xdr_adjust_iovec(struct kvec *iov, __be32 *p)
 138{
 139        return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 140}
 141
 142/*
 143 * XDR buffer helper functions
 144 */
 145extern void xdr_shift_buf(struct xdr_buf *, size_t);
 146extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 147extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 148extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
 149extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 150extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 151
 152/*
 153 * Helper structure for copying from an sk_buff.
 154 */
 155struct xdr_skb_reader {
 156        struct sk_buff  *skb;
 157        unsigned int    offset;
 158        size_t          count;
 159        __wsum          csum;
 160};
 161
 162typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
 163
 164size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
 165extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 166extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 167                struct xdr_skb_reader *, xdr_skb_read_actor);
 168
 169extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
 170extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
 171
 172struct xdr_array2_desc;
 173typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 174struct xdr_array2_desc {
 175        unsigned int elem_size;
 176        unsigned int array_len;
 177        unsigned int array_maxlen;
 178        xdr_xcode_elem_t xcode;
 179};
 180
 181extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 182                             struct xdr_array2_desc *desc);
 183extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 184                             struct xdr_array2_desc *desc);
 185
 186/*
 187 * Provide some simple tools for XDR buffer overflow-checking etc.
 188 */
 189struct xdr_stream {
 190        __be32 *p;              /* start of available buffer */
 191        struct xdr_buf *buf;    /* XDR buffer to read/write */
 192
 193        __be32 *end;            /* end of available buffer space */
 194        struct kvec *iov;       /* pointer to the current kvec */
 195};
 196
 197extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 198extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 199extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 200                unsigned int base, unsigned int len);
 201extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 202extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 203extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 204extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 205extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 206
 207#endif /* __KERNEL__ */
 208
 209#endif /* _SUNRPC_XDR_H_ */
 210