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 <asm/unaligned.h>
  15#include <linux/scatterlist.h>
  16
  17/*
  18 * Buffer adjustment
  19 */
  20#define XDR_QUADLEN(l)          (((l) + 3) >> 2)
  21
  22/*
  23 * Generic opaque `network object.' At the kernel level, this type
  24 * is used only by lockd.
  25 */
  26#define XDR_MAX_NETOBJ          1024
  27struct xdr_netobj {
  28        unsigned int            len;
  29        u8 *                    data;
  30};
  31
  32/*
  33 * This is the generic XDR function. rqstp is either a rpc_rqst (client
  34 * side) or svc_rqst pointer (server side).
  35 * Encode functions always assume there's enough room in the buffer.
  36 */
  37typedef int     (*kxdrproc_t)(void *rqstp, __be32 *data, void *obj);
  38
  39/*
  40 * Basic structure for transmission/reception of a client XDR message.
  41 * Features a header (for a linear buffer containing RPC headers
  42 * and the data payload for short messages), and then an array of
  43 * pages.
  44 * The tail iovec allows you to append data after the page array. Its
  45 * main interest is for appending padding to the pages in order to
  46 * satisfy the int_32-alignment requirements in RFC1832.
  47 *
  48 * For the future, we might want to string several of these together
  49 * in a list if anybody wants to make use of NFSv4 COMPOUND
  50 * operations and/or has a need for scatter/gather involving pages.
  51 */
  52struct xdr_buf {
  53        struct kvec     head[1],        /* RPC header + non-page data */
  54                        tail[1];        /* Appended after page data */
  55
  56        struct page **  pages;          /* Array of contiguous pages */
  57        unsigned int    page_base,      /* Start of page data */
  58                        page_len,       /* Length of page data */
  59                        flags;          /* Flags for data disposition */
  60#define XDRBUF_READ             0x01            /* target of file read */
  61#define XDRBUF_WRITE            0x02            /* source of file write */
  62
  63        unsigned int    buflen,         /* Total length of storage buffer */
  64                        len;            /* Length of XDR encoded message */
  65
  66};
  67
  68/*
  69 * pre-xdr'ed macros.
  70 */
  71
  72#define xdr_zero        cpu_to_be32(0)
  73#define xdr_one         cpu_to_be32(1)
  74#define xdr_two         cpu_to_be32(2)
  75
  76#define rpc_success             cpu_to_be32(RPC_SUCCESS)
  77#define rpc_prog_unavail        cpu_to_be32(RPC_PROG_UNAVAIL)
  78#define rpc_prog_mismatch       cpu_to_be32(RPC_PROG_MISMATCH)
  79#define rpc_proc_unavail        cpu_to_be32(RPC_PROC_UNAVAIL)
  80#define rpc_garbage_args        cpu_to_be32(RPC_GARBAGE_ARGS)
  81#define rpc_system_err          cpu_to_be32(RPC_SYSTEM_ERR)
  82#define rpc_drop_reply          cpu_to_be32(RPC_DROP_REPLY)
  83
  84#define rpc_auth_ok             cpu_to_be32(RPC_AUTH_OK)
  85#define rpc_autherr_badcred     cpu_to_be32(RPC_AUTH_BADCRED)
  86#define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
  87#define rpc_autherr_badverf     cpu_to_be32(RPC_AUTH_BADVERF)
  88#define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
  89#define rpc_autherr_tooweak     cpu_to_be32(RPC_AUTH_TOOWEAK)
  90#define rpcsec_gsserr_credproblem       cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
  91#define rpcsec_gsserr_ctxproblem        cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
  92#define rpc_autherr_oldseqnum   cpu_to_be32(101)
  93
  94/*
  95 * Miscellaneous XDR helper functions
  96 */
  97__be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
  98__be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
  99__be32 *xdr_encode_string(__be32 *p, const char *s);
 100__be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
 101                        unsigned int maxlen);
 102__be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
 103__be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
 104
 105void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
 106                         unsigned int);
 107void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 108                         struct page **, unsigned int, unsigned int);
 109
 110static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
 111{
 112        return xdr_encode_opaque(p, s, len);
 113}
 114
 115/*
 116 * Decode 64bit quantities (NFSv3 support)
 117 */
 118static inline __be32 *
 119xdr_encode_hyper(__be32 *p, __u64 val)
 120{
 121        put_unaligned_be64(val, p);
 122        return p + 2;
 123}
 124
 125static inline __be32 *
 126xdr_decode_hyper(__be32 *p, __u64 *valp)
 127{
 128        *valp = get_unaligned_be64(p);
 129        return p + 2;
 130}
 131
 132/*
 133 * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
 134 */
 135static inline int
 136xdr_adjust_iovec(struct kvec *iov, __be32 *p)
 137{
 138        return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 139}
 140
 141/*
 142 * XDR buffer helper functions
 143 */
 144extern void xdr_shift_buf(struct xdr_buf *, size_t);
 145extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 146extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 147extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
 148extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 149extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 150
 151/*
 152 * Helper structure for copying from an sk_buff.
 153 */
 154struct xdr_skb_reader {
 155        struct sk_buff  *skb;
 156        unsigned int    offset;
 157        size_t          count;
 158        __wsum          csum;
 159};
 160
 161typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
 162
 163size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
 164extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 165extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 166                struct xdr_skb_reader *, xdr_skb_read_actor);
 167
 168extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
 169extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
 170
 171struct xdr_array2_desc;
 172typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 173struct xdr_array2_desc {
 174        unsigned int elem_size;
 175        unsigned int array_len;
 176        unsigned int array_maxlen;
 177        xdr_xcode_elem_t xcode;
 178};
 179
 180extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 181                             struct xdr_array2_desc *desc);
 182extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 183                             struct xdr_array2_desc *desc);
 184
 185/*
 186 * Provide some simple tools for XDR buffer overflow-checking etc.
 187 */
 188struct xdr_stream {
 189        __be32 *p;              /* start of available buffer */
 190        struct xdr_buf *buf;    /* XDR buffer to read/write */
 191
 192        __be32 *end;            /* end of available buffer space */
 193        struct kvec *iov;       /* pointer to the current kvec */
 194};
 195
 196extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 197extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 198extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 199                unsigned int base, unsigned int len);
 200extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 201extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 202extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 203extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 204extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 205
 206#endif /* __KERNEL__ */
 207
 208#endif /* _SUNRPC_XDR_H_ */
 209