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 #include <linux/smp_lock.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
  27 struct 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  */
  37 typedef 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  */
  52 struct 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        __constant_htonl(0)
  73 #define xdr_one         __constant_htonl(1)
  74 #define xdr_two         __constant_htonl(2)
  75
  76 #define rpc_success             __constant_htonl(RPC_SUCCESS)
  77 #define rpc_prog_unavail        __constant_htonl(RPC_PROG_UNAVAIL)
  78 #define rpc_prog_mismatch       __constant_htonl(RPC_PROG_MISMATCH)
  79 #define rpc_proc_unavail        __constant_htonl(RPC_PROC_UNAVAIL)
  80 #define rpc_garbage_args        __constant_htonl(RPC_GARBAGE_ARGS)
  81 #define rpc_system_err          __constant_htonl(RPC_SYSTEM_ERR)
  82 #define rpc_drop_reply          __constant_htonl(RPC_DROP_REPLY)
  83
  84 #define rpc_auth_ok             __constant_htonl(RPC_AUTH_OK)
  85 #define rpc_autherr_badcred     __constant_htonl(RPC_AUTH_BADCRED)
  86 #define rpc_autherr_rejectedcred __constant_htonl(RPC_AUTH_REJECTEDCRED)
  87 #define rpc_autherr_badverf     __constant_htonl(RPC_AUTH_BADVERF)
  88 #define rpc_autherr_rejectedverf __constant_htonl(RPC_AUTH_REJECTEDVERF)
  89 #define rpc_autherr_tooweak     __constant_htonl(RPC_AUTH_TOOWEAK)
  90 #define rpcsec_gsserr_credproblem       __constant_htonl(RPCSEC_GSS_CREDPROBLEM)
  91 #define rpcsec_gsserr_ctxproblem        __constant_htonl(RPCSEC_GSS_CTXPROBLEM)
  92 #define rpc_autherr_oldseqnum   __constant_htonl(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
 105 void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
 106                          unsigned int);
 107 void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 108                          struct page **, unsigned int, unsigned int);
 109
 110 static 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  */
 118 static inline __be32 *
 119 xdr_encode_hyper(__be32 *p, __u64 val)
 120 {
 121         *p++ = htonl(val >> 32);
 122         *p++ = htonl(val & 0xFFFFFFFF);
 123         return p;
 124 }
 125
 126 static inline __be32 *
 127 xdr_decode_hyper(__be32 *p, __u64 *valp)
 128 {
 129         *valp  = ((__u64) ntohl(*p++)) << 32;
 130         *valp |= ntohl(*p++);
 131         return p;
 132 }
 133
 134 /*
 135  * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
 136  */
 137 static inline int
 138 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
 139 {
 140         return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 141 }
 142
 143 /*
 144  * XDR buffer helper functions
 145  */
 146 extern void xdr_shift_buf(struct xdr_buf *, size_t);
 147 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 148 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 149 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
 150 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 151 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 152
 153 /*
 154  * Helper structure for copying from an sk_buff.
 155  */
 156 struct xdr_skb_reader {
 157         struct sk_buff  *skb;
 158         unsigned int    offset;
 159         size_t          count;
 160         __wsum          csum;
 161 };
 162
 163 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
 164
 165 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
 166 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 167 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 168                 struct xdr_skb_reader *, xdr_skb_read_actor);
 169
 170 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
 171 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
 172
 173 struct xdr_array2_desc;
 174 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 175 struct xdr_array2_desc {
 176         unsigned int elem_size;
 177         unsigned int array_len;
 178         unsigned int array_maxlen;
 179         xdr_xcode_elem_t xcode;
 180 };
 181
 182 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 183                              struct xdr_array2_desc *desc);
 184 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 185                              struct xdr_array2_desc *desc);
 186
 187 /*
 188  * Provide some simple tools for XDR buffer overflow-checking etc.
 189  */
 190 struct xdr_stream {
 191         __be32 *p;              /* start of available buffer */
 192         struct xdr_buf *buf;    /* XDR buffer to read/write */
 193
 194         __be32 *end;            /* end of available buffer space */
 195         struct kvec *iov;       /* pointer to the current kvec */
 196 };
 197
 198 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 199 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 200 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 201                 unsigned int base, unsigned int len);
 202 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 203 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 204 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 205 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 206 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 207
 208 #endif /* __KERNEL__ */
 209
 210 #endif /* _SUNRPC_XDR_H_ */