include/exec/user/thunk.h

   1 /*
   2  *  Generic thunking code to convert data between host and target CPU
   3  *
   4  *  Copyright (c) 2003 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #ifndef THUNK_H
  20 #define THUNK_H
  21
  22 #include "cpu.h"
  23
  24 /* types enums definitions */
  25
  26 typedef enum argtype {
  27     TYPE_NULL,
  28     TYPE_CHAR,
  29     TYPE_SHORT,
  30     TYPE_INT,
  31     TYPE_LONG,
  32     TYPE_ULONG,
  33     TYPE_PTRVOID, /* pointer on unknown data */
  34     TYPE_LONGLONG,
  35     TYPE_ULONGLONG,
  36     TYPE_PTR,
  37     TYPE_ARRAY,
  38     TYPE_STRUCT,
  39     TYPE_OLDDEVT,
  40 } argtype;
  41
  42 #define MK_PTR(type) TYPE_PTR, type
  43 #define MK_ARRAY(type, size) TYPE_ARRAY, size, type
  44 #define MK_STRUCT(id) TYPE_STRUCT, id
  45
  46 #define THUNK_TARGET 0
  47 #define THUNK_HOST   1
  48
  49 typedef struct {
  50     /* standard struct handling */
  51     const argtype *field_types;
  52     int nb_fields;
  53     int *field_offsets[2];
  54     /* special handling */
  55     void (*convert[2])(void *dst, const void *src);
  56     int size[2];
  57     int align[2];
  58     const char *name;
  59 } StructEntry;
  60
  61 /* Translation table for bitmasks... */
  62 typedef struct bitmask_transtbl {
  63         unsigned int    x86_mask;
  64         unsigned int    x86_bits;
  65         unsigned int    alpha_mask;
  66         unsigned int    alpha_bits;
  67 } bitmask_transtbl;
  68
  69 void thunk_register_struct(int id, const char *name, const argtype *types);
  70 void thunk_register_struct_direct(int id, const char *name,
  71                                   const StructEntry *se1);
  72 const argtype *thunk_convert(void *dst, const void *src,
  73                              const argtype *type_ptr, int to_host);
  74 #ifndef NO_THUNK_TYPE_SIZE
  75
  76 extern StructEntry *struct_entries;
  77
  78 int thunk_type_size_array(const argtype *type_ptr, int is_host);
  79 int thunk_type_align_array(const argtype *type_ptr, int is_host);
  80
  81 static inline int thunk_type_size(const argtype *type_ptr, int is_host)
  82 {
  83     int type, size;
  84     const StructEntry *se;
  85
  86     type = *type_ptr;
  87     switch(type) {
  88     case TYPE_CHAR:
  89         return 1;
  90     case TYPE_SHORT:
  91         return 2;
  92     case TYPE_INT:
  93         return 4;
  94     case TYPE_LONGLONG:
  95     case TYPE_ULONGLONG:
  96         return 8;
  97     case TYPE_LONG:
  98     case TYPE_ULONG:
  99     case TYPE_PTRVOID:
 100     case TYPE_PTR:
 101         if (is_host) {
 102             return sizeof(void *);
 103         } else {
 104             return TARGET_ABI_BITS / 8;
 105         }
 106         break;
 107     case TYPE_OLDDEVT:
 108         if (is_host) {
 109 #if defined(HOST_X86_64)
 110             return 8;
 111 #elif defined(HOST_ALPHA) || defined(HOST_IA64) || defined(HOST_MIPS) || \
 112       defined(HOST_PARISC) || defined(HOST_SPARC64)
 113             return 4;
 114 #elif defined(HOST_PPC)
 115             return sizeof(void *);
 116 #else
 117             return 2;
 118 #endif
 119         } else {
 120 #if defined(TARGET_X86_64)
 121             return 8;
 122 #elif defined(TARGET_ALPHA) || defined(TARGET_IA64) || defined(TARGET_MIPS) || \
 123       defined(TARGET_PARISC) || defined(TARGET_SPARC64)
 124             return 4;
 125 #elif defined(TARGET_PPC)
 126             return TARGET_ABI_BITS / 8;
 127 #else
 128             return 2;
 129 #endif
 130         }
 131         break;
 132     case TYPE_ARRAY:
 133         size = type_ptr[1];
 134         return size * thunk_type_size_array(type_ptr + 2, is_host);
 135     case TYPE_STRUCT:
 136         se = struct_entries + type_ptr[1];
 137         return se->size[is_host];
 138     default:
 139         return -1;
 140     }
 141 }
 142
 143 static inline int thunk_type_align(const argtype *type_ptr, int is_host)
 144 {
 145     int type;
 146     const StructEntry *se;
 147
 148     type = *type_ptr;
 149     switch(type) {
 150     case TYPE_CHAR:
 151         return 1;
 152     case TYPE_SHORT:
 153         return 2;
 154     case TYPE_INT:
 155         return 4;
 156     case TYPE_LONGLONG:
 157     case TYPE_ULONGLONG:
 158         return 8;
 159     case TYPE_LONG:
 160     case TYPE_ULONG:
 161     case TYPE_PTRVOID:
 162     case TYPE_PTR:
 163         if (is_host) {
 164             return sizeof(void *);
 165         } else {
 166             return TARGET_ABI_BITS / 8;
 167         }
 168         break;
 169     case TYPE_OLDDEVT:
 170         return thunk_type_size(type_ptr, is_host);
 171     case TYPE_ARRAY:
 172         return thunk_type_align_array(type_ptr + 2, is_host);
 173     case TYPE_STRUCT:
 174         se = struct_entries + type_ptr[1];
 175         return se->align[is_host];
 176     default:
 177         return -1;
 178     }
 179 }
 180
 181 #endif /* NO_THUNK_TYPE_SIZE */
 182
 183 unsigned int target_to_host_bitmask(unsigned int x86_mask,
 184                                     const bitmask_transtbl * trans_tbl);
 185 unsigned int host_to_target_bitmask(unsigned int alpha_mask,
 186                                     const bitmask_transtbl * trans_tbl);
 187
 188 void thunk_init(unsigned int max_structs);
 189
 190 #endif