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
  26 struct 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  */
  36 typedef 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  */
  51 struct 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
 104 void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
 105                          unsigned int);
 106 void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 107                          struct page **, unsigned int, unsigned int);
 108
 109 static 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  */
 117 static inline __be32 *
 118 xdr_encode_hyper(__be32 *p, __u64 val)
 119 {
 120         *p++ = htonl(val >> 32);
 121         *p++ = htonl(val & 0xFFFFFFFF);
 122         return p;
 123 }
 124
 125 static inline __be32 *
 126 xdr_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  */
 136 static inline int
 137 xdr_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  */
 145 extern void xdr_shift_buf(struct xdr_buf *, size_t);
 146 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 147 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 148 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
 149 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 150 extern 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  */
 155 struct xdr_skb_reader {
 156         struct sk_buff  *skb;
 157         unsigned int    offset;
 158         size_t          count;
 159         __wsum          csum;
 160 };
 161
 162 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
 163
 164 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
 165 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 166 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 167                 struct xdr_skb_reader *, xdr_skb_read_actor);
 168
 169 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
 170 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
 171
 172 struct xdr_array2_desc;
 173 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 174 struct 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
 181 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 182                              struct xdr_array2_desc *desc);
 183 extern 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  */
 189 struct 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
 197 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 198 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 199 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 200                 unsigned int base, unsigned int len);
 201 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 202 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 203 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 204 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 205 extern 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_ */