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  * We're still requiring the BKL in the xdr code until it's been
  41  * more carefully audited, at which point this wrapper will become
  42  * unnecessary.
  43  */
  44 static inline int rpc_call_xdrproc(kxdrproc_t xdrproc, void *rqstp, __be32 *data, void *obj)
  45 {
  46         int ret;
  47
  48         lock_kernel();
  49         ret = xdrproc(rqstp, data, obj);
  50         unlock_kernel();
  51         return ret;
  52 }
  53
  54 /*
  55  * Basic structure for transmission/reception of a client XDR message.
  56  * Features a header (for a linear buffer containing RPC headers
  57  * and the data payload for short messages), and then an array of
  58  * pages.
  59  * The tail iovec allows you to append data after the page array. Its
  60  * main interest is for appending padding to the pages in order to
  61  * satisfy the int_32-alignment requirements in RFC1832.
  62  *
  63  * For the future, we might want to string several of these together
  64  * in a list if anybody wants to make use of NFSv4 COMPOUND
  65  * operations and/or has a need for scatter/gather involving pages.
  66  */
  67 struct xdr_buf {
  68         struct kvec     head[1],        /* RPC header + non-page data */
  69                         tail[1];        /* Appended after page data */
  70
  71         struct page **  pages;          /* Array of contiguous pages */
  72         unsigned int    page_base,      /* Start of page data */
  73                         page_len;       /* Length of page data */
  74
  75         unsigned int    buflen,         /* Total length of storage buffer */
  76                         len;            /* Length of XDR encoded message */
  77
  78 };
  79
  80 /*
  81  * pre-xdr'ed macros.
  82  */
  83
  84 #define xdr_zero        __constant_htonl(0)
  85 #define xdr_one         __constant_htonl(1)
  86 #define xdr_two         __constant_htonl(2)
  87
  88 #define rpc_success             __constant_htonl(RPC_SUCCESS)
  89 #define rpc_prog_unavail        __constant_htonl(RPC_PROG_UNAVAIL)
  90 #define rpc_prog_mismatch       __constant_htonl(RPC_PROG_MISMATCH)
  91 #define rpc_proc_unavail        __constant_htonl(RPC_PROC_UNAVAIL)
  92 #define rpc_garbage_args        __constant_htonl(RPC_GARBAGE_ARGS)
  93 #define rpc_system_err          __constant_htonl(RPC_SYSTEM_ERR)
  94 #define rpc_drop_reply          __constant_htonl(RPC_DROP_REPLY)
  95
  96 #define rpc_auth_ok             __constant_htonl(RPC_AUTH_OK)
  97 #define rpc_autherr_badcred     __constant_htonl(RPC_AUTH_BADCRED)
  98 #define rpc_autherr_rejectedcred __constant_htonl(RPC_AUTH_REJECTEDCRED)
  99 #define rpc_autherr_badverf     __constant_htonl(RPC_AUTH_BADVERF)
 100 #define rpc_autherr_rejectedverf __constant_htonl(RPC_AUTH_REJECTEDVERF)
 101 #define rpc_autherr_tooweak     __constant_htonl(RPC_AUTH_TOOWEAK)
 102 #define rpcsec_gsserr_credproblem       __constant_htonl(RPCSEC_GSS_CREDPROBLEM)
 103 #define rpcsec_gsserr_ctxproblem        __constant_htonl(RPCSEC_GSS_CTXPROBLEM)
 104 #define rpc_autherr_oldseqnum   __constant_htonl(101)
 105
 106 /*
 107  * Miscellaneous XDR helper functions
 108  */
 109 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
 110 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
 111 __be32 *xdr_encode_string(__be32 *p, const char *s);
 112 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, int *lenp, int maxlen);
 113 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
 114 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);
 115
 116 void    xdr_encode_pages(struct xdr_buf *, struct page **, unsigned int,
 117                          unsigned int);
 118 void    xdr_inline_pages(struct xdr_buf *, unsigned int,
 119                          struct page **, unsigned int, unsigned int);
 120
 121 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
 122 {
 123         return xdr_encode_opaque(p, s, len);
 124 }
 125
 126 /*
 127  * Decode 64bit quantities (NFSv3 support)
 128  */
 129 static inline __be32 *
 130 xdr_encode_hyper(__be32 *p, __u64 val)
 131 {
 132         *p++ = htonl(val >> 32);
 133         *p++ = htonl(val & 0xFFFFFFFF);
 134         return p;
 135 }
 136
 137 static inline __be32 *
 138 xdr_decode_hyper(__be32 *p, __u64 *valp)
 139 {
 140         *valp  = ((__u64) ntohl(*p++)) << 32;
 141         *valp |= ntohl(*p++);
 142         return p;
 143 }
 144
 145 /*
 146  * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
 147  */
 148 static inline int
 149 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
 150 {
 151         return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 152 }
 153
 154 /*
 155  * XDR buffer helper functions
 156  */
 157 extern void xdr_shift_buf(struct xdr_buf *, size_t);
 158 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 159 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 160 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
 161 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 162 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 163
 164 /*
 165  * Helper structure for copying from an sk_buff.
 166  */
 167 struct xdr_skb_reader {
 168         struct sk_buff  *skb;
 169         unsigned int    offset;
 170         size_t          count;
 171         __wsum          csum;
 172 };
 173
 174 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);
 175
 176 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
 177 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 178 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 179                 struct xdr_skb_reader *, xdr_skb_read_actor);
 180
 181 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
 182 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);
 183
 184 struct xdr_array2_desc;
 185 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 186 struct xdr_array2_desc {
 187         unsigned int elem_size;
 188         unsigned int array_len;
 189         unsigned int array_maxlen;
 190         xdr_xcode_elem_t xcode;
 191 };
 192
 193 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 194                              struct xdr_array2_desc *desc);
 195 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 196                              struct xdr_array2_desc *desc);
 197
 198 /*
 199  * Provide some simple tools for XDR buffer overflow-checking etc.
 200  */
 201 struct xdr_stream {
 202         __be32 *p;              /* start of available buffer */
 203         struct xdr_buf *buf;    /* XDR buffer to read/write */
 204
 205         __be32 *end;            /* end of available buffer space */
 206         struct kvec *iov;       /* pointer to the current kvec */
 207 };
 208
 209 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 210 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 211 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 212                 unsigned int base, unsigned int len);
 213 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 214 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 215 extern void xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 216 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 217 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);
 218
 219 #endif /* __KERNEL__ */
 220
 221 #endif /* _SUNRPC_XDR_H_ */