thunk.c

   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 2.1 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 #include "qemu/osdep.h"
  20 #include "qemu/log.h"
  21
  22 #include "qemu.h"
  23 #include "exec/user/thunk.h"
  24
  25 //#define DEBUG
  26
  27 static unsigned int max_struct_entries;
  28 StructEntry *struct_entries;
  29
  30 static const argtype *thunk_type_next_ptr(const argtype *type_ptr);
  31
  32 static inline const argtype *thunk_type_next(const argtype *type_ptr)
  33 {
  34     int type;
  35
  36     type = *type_ptr++;
  37     switch(type) {
  38     case TYPE_CHAR:
  39     case TYPE_SHORT:
  40     case TYPE_INT:
  41     case TYPE_LONGLONG:
  42     case TYPE_ULONGLONG:
  43     case TYPE_LONG:
  44     case TYPE_ULONG:
  45     case TYPE_PTRVOID:
  46     case TYPE_OLDDEVT:
  47         return type_ptr;
  48     case TYPE_PTR:
  49         return thunk_type_next_ptr(type_ptr);
  50     case TYPE_ARRAY:
  51         return thunk_type_next_ptr(type_ptr + 1);
  52     case TYPE_STRUCT:
  53         return type_ptr + 1;
  54     default:
  55         return NULL;
  56     }
  57 }
  58
  59 static const argtype *thunk_type_next_ptr(const argtype *type_ptr)
  60 {
  61     return thunk_type_next(type_ptr);
  62 }
  63
  64 void thunk_register_struct(int id, const char *name, const argtype *types)
  65 {
  66     const argtype *type_ptr;
  67     StructEntry *se;
  68     int nb_fields, offset, max_align, align, size, i, j;
  69
  70     assert(id < max_struct_entries);
  71
  72     /* first we count the number of fields */
  73     type_ptr = types;
  74     nb_fields = 0;
  75     while (*type_ptr != TYPE_NULL) {
  76         type_ptr = thunk_type_next(type_ptr);
  77         nb_fields++;
  78     }
  79     assert(nb_fields > 0);
  80     se = struct_entries + id;
  81     se->field_types = types;
  82     se->nb_fields = nb_fields;
  83     se->name = name;
  84 #ifdef DEBUG
  85     printf("struct %s: id=%d nb_fields=%d\n",
  86            se->name, id, se->nb_fields);
  87 #endif
  88     /* now we can alloc the data */
  89
  90     for (i = 0; i < ARRAY_SIZE(se->field_offsets); i++) {
  91         offset = 0;
  92         max_align = 1;
  93         se->field_offsets[i] = g_new(int, nb_fields);
  94         type_ptr = se->field_types;
  95         for(j = 0;j < nb_fields; j++) {
  96             size = thunk_type_size(type_ptr, i);
  97             align = thunk_type_align(type_ptr, i);
  98             offset = (offset + align - 1) & ~(align - 1);
  99             se->field_offsets[i][j] = offset;
 100             offset += size;
 101             if (align > max_align)
 102                 max_align = align;
 103             type_ptr = thunk_type_next(type_ptr);
 104         }
 105         offset = (offset + max_align - 1) & ~(max_align - 1);
 106         se->size[i] = offset;
 107         se->align[i] = max_align;
 108 #ifdef DEBUG
 109         printf("%s: size=%d align=%d\n",
 110                i == THUNK_HOST ? "host" : "target", offset, max_align);
 111 #endif
 112     }
 113 }
 114
 115 void thunk_register_struct_direct(int id, const char *name,
 116                                   const StructEntry *se1)
 117 {
 118     StructEntry *se;
 119
 120     assert(id < max_struct_entries);
 121     se = struct_entries + id;
 122     *se = *se1;
 123     se->name = name;
 124 }
 125
 126
 127 /* now we can define the main conversion functions */
 128 const argtype *thunk_convert(void *dst, const void *src,
 129                              const argtype *type_ptr, int to_host)
 130 {
 131     int type;
 132
 133     type = *type_ptr++;
 134     switch(type) {
 135     case TYPE_CHAR:
 136         *(uint8_t *)dst = *(uint8_t *)src;
 137         break;
 138     case TYPE_SHORT:
 139         *(uint16_t *)dst = tswap16(*(uint16_t *)src);
 140         break;
 141     case TYPE_INT:
 142         *(uint32_t *)dst = tswap32(*(uint32_t *)src);
 143         break;
 144     case TYPE_LONGLONG:
 145     case TYPE_ULONGLONG:
 146         *(uint64_t *)dst = tswap64(*(uint64_t *)src);
 147         break;
 148 #if HOST_LONG_BITS == 32 && TARGET_ABI_BITS == 32
 149     case TYPE_LONG:
 150     case TYPE_ULONG:
 151     case TYPE_PTRVOID:
 152         *(uint32_t *)dst = tswap32(*(uint32_t *)src);
 153         break;
 154 #elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 32
 155     case TYPE_LONG:
 156     case TYPE_ULONG:
 157     case TYPE_PTRVOID:
 158         if (to_host) {
 159             if (type == TYPE_LONG) {
 160                 /* sign extension */
 161                 *(uint64_t *)dst = (int32_t)tswap32(*(uint32_t *)src);
 162             } else {
 163                 *(uint64_t *)dst = tswap32(*(uint32_t *)src);
 164             }
 165         } else {
 166             *(uint32_t *)dst = tswap32(*(uint64_t *)src & 0xffffffff);
 167         }
 168         break;
 169 #elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64
 170     case TYPE_LONG:
 171     case TYPE_ULONG:
 172     case TYPE_PTRVOID:
 173         *(uint64_t *)dst = tswap64(*(uint64_t *)src);
 174         break;
 175 #elif HOST_LONG_BITS == 32 && TARGET_ABI_BITS == 64
 176     case TYPE_LONG:
 177     case TYPE_ULONG:
 178     case TYPE_PTRVOID:
 179         if (to_host) {
 180             *(uint32_t *)dst = tswap64(*(uint64_t *)src);
 181         } else {
 182             if (type == TYPE_LONG) {
 183                 /* sign extension */
 184                 *(uint64_t *)dst = tswap64(*(int32_t *)src);
 185             } else {
 186                 *(uint64_t *)dst = tswap64(*(uint32_t *)src);
 187             }
 188         }
 189         break;
 190 #else
 191 #warning unsupported conversion
 192 #endif
 193     case TYPE_OLDDEVT:
 194     {
 195         uint64_t val = 0;
 196         switch (thunk_type_size(type_ptr - 1, !to_host)) {
 197         case 2:
 198             val = *(uint16_t *)src;
 199             break;
 200         case 4:
 201             val = *(uint32_t *)src;
 202             break;
 203         case 8:
 204             val = *(uint64_t *)src;
 205             break;
 206         }
 207         switch (thunk_type_size(type_ptr - 1, to_host)) {
 208         case 2:
 209             *(uint16_t *)dst = tswap16(val);
 210             break;
 211         case 4:
 212             *(uint32_t *)dst = tswap32(val);
 213             break;
 214         case 8:
 215             *(uint64_t *)dst = tswap64(val);
 216             break;
 217         }
 218         break;
 219     }
 220     case TYPE_ARRAY:
 221         {
 222             int array_length, i, dst_size, src_size;
 223             const uint8_t *s;
 224             uint8_t  *d;
 225
 226             array_length = *type_ptr++;
 227             dst_size = thunk_type_size(type_ptr, to_host);
 228             src_size = thunk_type_size(type_ptr, 1 - to_host);
 229             d = dst;
 230             s = src;
 231             for(i = 0;i < array_length; i++) {
 232                 thunk_convert(d, s, type_ptr, to_host);
 233                 d += dst_size;
 234                 s += src_size;
 235             }
 236             type_ptr = thunk_type_next(type_ptr);
 237         }
 238         break;
 239     case TYPE_STRUCT:
 240         {
 241             int i;
 242             const StructEntry *se;
 243             const uint8_t *s;
 244             uint8_t  *d;
 245             const argtype *field_types;
 246             const int *dst_offsets, *src_offsets;
 247
 248             assert(*type_ptr < max_struct_entries);
 249             se = struct_entries + *type_ptr++;
 250             if (se->convert[0] != NULL) {
 251                 /* specific conversion is needed */
 252                 (*se->convert[to_host])(dst, src);
 253             } else {
 254                 /* standard struct conversion */
 255                 field_types = se->field_types;
 256                 dst_offsets = se->field_offsets[to_host];
 257                 src_offsets = se->field_offsets[1 - to_host];
 258                 d = dst;
 259                 s = src;
 260                 for(i = 0;i < se->nb_fields; i++) {
 261                     field_types = thunk_convert(d + dst_offsets[i],
 262                                                 s + src_offsets[i],
 263                                                 field_types, to_host);
 264                 }
 265             }
 266         }
 267         break;
 268     default:
 269         fprintf(stderr, "Invalid type 0x%x\n", type);
 270         break;
 271     }
 272     return type_ptr;
 273 }
 274
 275 const argtype *thunk_print(void *arg, const argtype *type_ptr)
 276 {
 277     int type;
 278
 279     type = *type_ptr++;
 280
 281     switch (type) {
 282     case TYPE_CHAR:
 283         qemu_log("%c", *(uint8_t *)arg);
 284         break;
 285     case TYPE_SHORT:
 286         qemu_log("%" PRId16, tswap16(*(uint16_t *)arg));
 287         break;
 288     case TYPE_INT:
 289         qemu_log("%" PRId32, tswap32(*(uint32_t *)arg));
 290         break;
 291     case TYPE_LONGLONG:
 292         qemu_log("%" PRId64, tswap64(*(uint64_t *)arg));
 293         break;
 294     case TYPE_ULONGLONG:
 295         qemu_log("%" PRIu64, tswap64(*(uint64_t *)arg));
 296         break;
 297 #if HOST_LONG_BITS == 32 && TARGET_ABI_BITS == 32
 298     case TYPE_PTRVOID:
 299         qemu_log("0x%" PRIx32, tswap32(*(uint32_t *)arg));
 300         break;
 301     case TYPE_LONG:
 302         qemu_log("%" PRId32, tswap32(*(uint32_t *)arg));
 303         break;
 304     case TYPE_ULONG:
 305         qemu_log("%" PRIu32, tswap32(*(uint32_t *)arg));
 306         break;
 307 #elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 32
 308     case TYPE_PTRVOID:
 309         qemu_log("0x%" PRIx32, tswap32(*(uint64_t *)arg & 0xffffffff));
 310         break;
 311     case TYPE_LONG:
 312         qemu_log("%" PRId32, tswap32(*(uint64_t *)arg & 0xffffffff));
 313         break;
 314     case TYPE_ULONG:
 315         qemu_log("%" PRIu32, tswap32(*(uint64_t *)arg & 0xffffffff));
 316         break;
 317 #elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64
 318     case TYPE_PTRVOID:
 319         qemu_log("0x%" PRIx64, tswap64(*(uint64_t *)arg));
 320         break;
 321     case TYPE_LONG:
 322         qemu_log("%" PRId64, tswap64(*(uint64_t *)arg));
 323         break;
 324     case TYPE_ULONG:
 325         qemu_log("%" PRIu64, tswap64(*(uint64_t *)arg));
 326         break;
 327 #else
 328     case TYPE_PTRVOID:
 329         qemu_log("0x%" PRIx64, tswap64(*(uint64_t *)arg));
 330         break;
 331     case TYPE_LONG:
 332         qemu_log("%" PRId64, tswap64(*(uint64_t *)arg));
 333         break;
 334     case TYPE_ULONG:
 335         qemu_log("%" PRIu64, tswap64(*(uint64_t *)arg));
 336         break;
 337 #endif
 338     case TYPE_OLDDEVT:
 339     {
 340         uint64_t val = 0;
 341         switch (thunk_type_size(type_ptr - 1, 1)) {
 342         case 2:
 343             val = *(uint16_t *)arg;
 344             break;
 345         case 4:
 346             val = *(uint32_t *)arg;
 347             break;
 348         case 8:
 349             val = *(uint64_t *)arg;
 350             break;
 351         }
 352         switch (thunk_type_size(type_ptr - 1, 0)) {
 353         case 2:
 354             qemu_log("%" PRIu16, tswap16(val));
 355             break;
 356         case 4:
 357             qemu_log("%" PRIu32, tswap32(val));
 358             break;
 359         case 8:
 360             qemu_log("%" PRIu64, tswap64(val));
 361             break;
 362         }
 363     }
 364     break;
 365     case TYPE_ARRAY:
 366         {
 367             int i, array_length, arg_size;
 368             uint8_t *a;
 369             int is_string = 0;
 370
 371             array_length = *type_ptr++;
 372             arg_size = thunk_type_size(type_ptr, 0);
 373             a = arg;
 374
 375             if (*type_ptr == TYPE_CHAR) {
 376                 qemu_log("\"");
 377                 is_string = 1;
 378             } else {
 379                 qemu_log("[");
 380             }
 381
 382             for (i = 0; i < array_length; i++) {
 383                 if (i > 0 && !is_string) {
 384                     qemu_log(",");
 385                 }
 386                 thunk_print(a, type_ptr);
 387                 a += arg_size;
 388             }
 389
 390             if (is_string) {
 391                 qemu_log("\"");
 392             } else {
 393                 qemu_log("]");
 394             }
 395
 396             type_ptr = thunk_type_next(type_ptr);
 397         }
 398         break;
 399     case TYPE_STRUCT:
 400         {
 401             int i;
 402             const StructEntry *se;
 403             uint8_t  *a;
 404             const argtype *field_types;
 405             const int *arg_offsets;
 406
 407             se = struct_entries + *type_ptr++;
 408
 409             if (se->print != NULL) {
 410                 se->print(arg);
 411             } else {
 412                 a = arg;
 413
 414                 field_types = se->field_types;
 415                 arg_offsets = se->field_offsets[0];
 416
 417                 qemu_log("{");
 418                 for (i = 0; i < se->nb_fields; i++) {
 419                     if (i > 0) {
 420                         qemu_log(",");
 421                     }
 422                     field_types = thunk_print(a + arg_offsets[i], field_types);
 423                 }
 424                 qemu_log("}");
 425             }
 426         }
 427         break;
 428     default:
 429         g_assert_not_reached();
 430     }
 431     return type_ptr;
 432 }
 433
 434 /* from em86 */
 435
 436 /* Utility function: Table-driven functions to translate bitmasks
 437  * between host and target formats
 438  */
 439 unsigned int target_to_host_bitmask(unsigned int target_mask,
 440                                     const bitmask_transtbl * trans_tbl)
 441 {
 442     const bitmask_transtbl *btp;
 443     unsigned int host_mask = 0;
 444
 445     for (btp = trans_tbl; btp->target_mask && btp->host_mask; btp++) {
 446         if ((target_mask & btp->target_mask) == btp->target_bits) {
 447             host_mask |= btp->host_bits;
 448         }
 449     }
 450     return host_mask;
 451 }
 452
 453 unsigned int host_to_target_bitmask(unsigned int host_mask,
 454                                     const bitmask_transtbl * trans_tbl)
 455 {
 456     const bitmask_transtbl *btp;
 457     unsigned int target_mask = 0;
 458
 459     for (btp = trans_tbl; btp->target_mask && btp->host_mask; btp++) {
 460         if ((host_mask & btp->host_mask) == btp->host_bits) {
 461             target_mask |= btp->target_bits;
 462         }
 463     }
 464     return target_mask;
 465 }
 466
 467 int thunk_type_size_array(const argtype *type_ptr, int is_host)
 468 {
 469     return thunk_type_size(type_ptr, is_host);
 470 }
 471
 472 int thunk_type_align_array(const argtype *type_ptr, int is_host)
 473 {
 474     return thunk_type_align(type_ptr, is_host);
 475 }
 476
 477 void thunk_init(unsigned int max_structs)
 478 {
 479     max_struct_entries = max_structs;
 480     struct_entries = g_new0(StructEntry, max_structs);
 481 }