src/runtime/coreparse.c

   1 /*
   2  * A saved SBCL system is a .core file; the code here helps us accept
   3  * such a file as input.
   4  */
   5
   6 /*
   7  * This software is part of the SBCL system. See the README file for
   8  * more information.
   9  *
  10  * This software is derived from the CMU CL system, which was
  11  * written at Carnegie Mellon University and released into the
  12  * public domain. The software is in the public domain and is
  13  * provided with absolutely no warranty. See the COPYING and CREDITS
  14  * files for more information.
  15  */
  16
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <sys/file.h>
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <fcntl.h>
  24 #include <unistd.h>
  25
  26 #include "sbcl.h"
  27
  28 #ifndef LISP_FEATURE_WIN32
  29 #ifdef LISP_FEATURE_LINUX
  30 /* For madvise */
  31 # define _BSD_SOURCE
  32 #endif
  33 #include <sys/mman.h>
  34 #endif
  35
  36 #include "os.h"
  37 #include "runtime.h"
  38 #include "globals.h"
  39 #include "core.h"
  40 #include "arch.h"
  41 #include "interr.h"
  42 #include "thread.h"
  43
  44 #include "validate.h"
  45 #include "gc-internal.h"
  46 #include "runtime-options.h"
  47
  48 #include <errno.h>
  49
  50 #ifdef LISP_FEATURE_SB_CORE_COMPRESSION
  51 # include <zlib.h>
  52 #endif
  53
  54 unsigned char build_id[] =
  55 #include "../../output/build-id.tmp"
  56 ;
  57
  58 int
  59 open_binary(char *filename, int mode)
  60 {
  61 #ifdef LISP_FEATURE_WIN32
  62     mode |= O_BINARY;
  63 #endif
  64
  65     return open(filename, mode);
  66 }
  67
  68
  69 static struct runtime_options *
  70 read_runtime_options(int fd)
  71 {
  72     os_vm_size_t optarray[RUNTIME_OPTIONS_WORDS];
  73     struct runtime_options *options = NULL;
  74
  75     if (read(fd, optarray, RUNTIME_OPTIONS_WORDS * sizeof(os_vm_size_t)) !=
  76         RUNTIME_OPTIONS_WORDS * sizeof(size_t)) {
  77         return NULL;
  78     }
  79
  80     if ((RUNTIME_OPTIONS_MAGIC != optarray[0]) || (0 == optarray[1])) {
  81         return NULL;
  82     }
  83
  84     options = successful_malloc(sizeof(struct runtime_options));
  85
  86     options->dynamic_space_size = optarray[2];
  87     options->thread_control_stack_size = optarray[3];
  88
  89     return options;
  90 }
  91
  92 void
  93 maybe_initialize_runtime_options(int fd)
  94 {
  95     struct runtime_options *new_runtime_options;
  96     off_t end_offset = sizeof(lispobj) +
  97         sizeof(os_vm_offset_t) +
  98         (RUNTIME_OPTIONS_WORDS * sizeof(size_t));
  99
 100     lseek(fd, -end_offset, SEEK_END);
 101
 102     if ((new_runtime_options = read_runtime_options(fd))) {
 103         runtime_options = new_runtime_options;
 104     }
 105 }
 106
 107 /* Search 'filename' for an embedded core.  An SBCL core has, at the
 108  * end of the file, a trailer containing optional saved runtime
 109  * options, the start of the core (an os_vm_offset_t), and a final
 110  * signature word (the lispobj CORE_MAGIC).  If this trailer is found
 111  * at the end of the file, the start of the core can be determined
 112  * from the core size.
 113  *
 114  * If an embedded core is present, this returns the offset into the
 115  * file to load the core from, or -1 if no core is present. */
 116 os_vm_offset_t
 117 search_for_embedded_core(char *filename)
 118 {
 119     lispobj header;
 120     os_vm_offset_t lispobj_size = sizeof(lispobj);
 121     os_vm_offset_t trailer_size = lispobj_size + sizeof(os_vm_offset_t);
 122     os_vm_offset_t core_start, pos;
 123     int fd = -1;
 124
 125     if ((fd = open_binary(filename, O_RDONLY)) < 0)
 126         goto lose;
 127
 128     if (read(fd, &header, (size_t)lispobj_size) < lispobj_size)
 129         goto lose;
 130     if (header == CORE_MAGIC) {
 131         /* This file is a real core, not an embedded core.  Return 0 to
 132          * indicate where the core starts, and do not look for runtime
 133          * options in this case. */
 134         return 0;
 135     }
 136
 137     if (lseek(fd, -lispobj_size, SEEK_END) < 0)
 138         goto lose;
 139     if (read(fd, &header, (size_t)lispobj_size) < lispobj_size)
 140         goto lose;
 141
 142     if (header == CORE_MAGIC) {
 143         if (lseek(fd, -trailer_size, SEEK_END) < 0)
 144             goto lose;
 145         if (read(fd, &core_start, sizeof(os_vm_offset_t)) < 0)
 146             goto lose;
 147
 148         if (lseek(fd, core_start, SEEK_SET) < 0)
 149             goto lose;
 150         pos = lseek(fd, 0, SEEK_CUR);
 151
 152         if (read(fd, &header, (size_t)lispobj_size) < lispobj_size)
 153             goto lose;
 154
 155         if (header != CORE_MAGIC)
 156             goto lose;
 157
 158         maybe_initialize_runtime_options(fd);
 159
 160         close(fd);
 161         return pos;
 162     }
 163
 164 lose:
 165     if (fd != -1)
 166         close(fd);
 167
 168     return -1;
 169 }
 170
 171 /* If more platforms doesn't support overlapping mmap rename this
 172  * def to something like ifdef nommapoverlap */
 173 /* currently hpux only */
 174 #ifdef LISP_FEATURE_HPUX
 175 os_vm_address_t copy_core_bytes(int fd, os_vm_offset_t offset,
 176                                 os_vm_address_t addr, int len)
 177 {
 178   unsigned char buf[4096];
 179   int c,x;
 180   int old_fd = lseek(fd, 0, SEEK_CUR);
 181
 182   if(len & (4096-1)){
 183     fprintf(stderr, "cant copy a slice of core because slice-length is not of page size(4096)\n");
 184     exit(-1);
 185   }
 186   if(old_fd < 0){
 187     fprintf(stderr, "cant perform lseek() on corefile\n");
 188   }
 189   lseek(fd, offset, SEEK_SET);
 190   if(fd < 0){
 191     fprintf(stderr, "cant perform lseek(%u,%lu,SEEK_SET) on corefile\n", fd, offset);
 192   }
 193   for(x = 0; x < len; x += 4096){
 194     c = read(fd, buf, 4096);
 195     if(c != 4096){
 196       fprintf(stderr, "cant read memory area from corefile at position %lu, got %d\n", offset + x, c);
 197       exit(-1);
 198     }
 199     memcpy(addr+x, buf, 4096);
 200   }
 201   os_flush_icache(addr, len);
 202   return addr;
 203 }
 204 #endif
 205
 206 #ifdef LISP_FEATURE_SB_CORE_COMPRESSION
 207 # define ZLIB_BUFFER_SIZE (1u<<16)
 208 os_vm_address_t inflate_core_bytes(int fd, os_vm_offset_t offset,
 209                                    os_vm_address_t addr, int len)
 210 {
 211     z_stream stream;
 212     unsigned char buf[ZLIB_BUFFER_SIZE];
 213     int ret;
 214
 215     if (-1 == lseek(fd, offset, SEEK_SET)) {
 216         lose("Unable to lseek() on corefile\n");
 217     }
 218
 219     stream.zalloc = NULL;
 220     stream.zfree = NULL;
 221     stream.opaque = NULL;
 222     stream.avail_in = 0;
 223     stream.next_in = buf;
 224
 225     ret = inflateInit(&stream);
 226     if (ret != Z_OK)
 227         lose("zlib error %i\n", ret);
 228
 229     stream.next_out  = (void*)addr;
 230     stream.avail_out = len;
 231     do {
 232         ssize_t count = read(fd, buf, sizeof(buf));
 233         if (count < 0)
 234             lose("unable to read core file (errno = %i)\n", errno);
 235         stream.next_in = buf;
 236         stream.avail_in = count;
 237         if (count == 0) break;
 238         ret = inflate(&stream, Z_NO_FLUSH);
 239         switch (ret) {
 240         case Z_STREAM_END:
 241             break;
 242         case Z_OK:
 243             if (stream.avail_out == 0)
 244                 lose("Runaway gzipped core directory... aborting\n");
 245             if (stream.avail_in > 0)
 246                 lose("zlib inflate returned without fully"
 247                      "using up input buffer... aborting\n");
 248             break;
 249         default:
 250             lose("zlib inflate error: %i\n", ret);
 251             break;
 252         }
 253     } while (ret != Z_STREAM_END);
 254
 255     if (stream.avail_out > 0) {
 256         if (stream.avail_out >= os_vm_page_size)
 257             fprintf(stderr, "Warning: gzipped core directory significantly"
 258                     "shorter than expected (%lu bytes)", (unsigned long)stream.avail_out);
 259         /* Is this needed? */
 260         memset(stream.next_out, 0, stream.avail_out);
 261     }
 262
 263     inflateEnd(&stream);
 264     return addr;
 265 }
 266 # undef ZLIB_BUFFER_SIZE
 267 #endif
 268
 269 int merge_core_pages = -1;
 270
 271 static void
 272 process_directory(int fd, lispobj *ptr, int count, os_vm_offset_t file_offset)
 273 {
 274     struct ndir_entry *entry;
 275     int compressed;
 276
 277     FSHOW((stderr, "/process_directory(..), count=%d\n", count));
 278
 279     for (entry = (struct ndir_entry *) ptr; --count>= 0; ++entry) {
 280         compressed = 0;
 281         long id = entry->identifier;
 282         if (id <= (MAX_CORE_SPACE_ID | DEFLATED_CORE_SPACE_ID_FLAG)) {
 283             if (id & DEFLATED_CORE_SPACE_ID_FLAG)
 284                 compressed = 1;
 285             id &= ~(DEFLATED_CORE_SPACE_ID_FLAG);
 286         }
 287         long offset = os_vm_page_size * (1 + entry->data_page);
 288         os_vm_address_t addr =
 289             (os_vm_address_t) (os_vm_page_size * entry->address);
 290         lispobj *free_pointer = (lispobj *) addr + entry->nwords;
 291         unsigned long len = os_vm_page_size * entry->page_count;
 292         if (len != 0) {
 293             os_vm_address_t real_addr;
 294             FSHOW((stderr, "/mapping %ld(0x%lx) bytes at 0x%lx\n",
 295                    (long)len, (long)len, (unsigned long)addr));
 296             if (compressed) {
 297 #ifdef LISP_FEATURE_SB_CORE_COMPRESSION
 298                 real_addr = inflate_core_bytes(fd, offset + file_offset, addr, len);
 299 #else
 300                 lose("This runtime was not built with zlib-compressed core support... aborting\n");
 301 #endif
 302             } else {
 303 #ifdef LISP_FEATURE_HPUX
 304                 real_addr = copy_core_bytes(fd, offset + file_offset, addr, len);
 305 #else
 306                 real_addr = os_map(fd, offset + file_offset, addr, len);
 307 #endif
 308             }
 309             if (real_addr != addr) {
 310                 lose("file mapped in wrong place! "
 311                      "(0x%08x != 0x%08lx)\n",
 312                      real_addr,
 313                      addr);
 314             }
 315         }
 316
 317 #ifdef MADV_MERGEABLE
 318         if ((merge_core_pages == 1)
 319             || ((merge_core_pages == -1) && compressed)) {
 320                 madvise(addr, len, MADV_MERGEABLE);
 321         }
 322 #endif
 323
 324         FSHOW((stderr, "/space id = %ld, free pointer = 0x%lx\n",
 325                id, (unsigned long)free_pointer));
 326
 327         switch (id) {
 328         case DYNAMIC_CORE_SPACE_ID:
 329             if (len > dynamic_space_size) {
 330                 fprintf(stderr,
 331                         "dynamic space too small for core: %ldKiB required, %ldKiB available.\n",
 332                         len >> 10,
 333                         (long)dynamic_space_size >> 10);
 334                 exit(1);
 335             }
 336 #ifdef LISP_FEATURE_GENCGC
 337             if (addr != (os_vm_address_t)DYNAMIC_SPACE_START) {
 338                 fprintf(stderr, "in core: 0x%lx; in runtime: 0x%lx \n",
 339                         (long)addr, (long)DYNAMIC_SPACE_START);
 340                 lose("core/runtime address mismatch: DYNAMIC_SPACE_START\n");
 341             }
 342 #else
 343             if ((addr != (os_vm_address_t)DYNAMIC_0_SPACE_START) &&
 344                 (addr != (os_vm_address_t)DYNAMIC_1_SPACE_START)) {
 345                 fprintf(stderr, "in core: 0x%lx; in runtime: 0x%lx or 0x%lx\n",
 346                         (long)addr,
 347                         (long)DYNAMIC_0_SPACE_START,
 348                         (long)DYNAMIC_1_SPACE_START);
 349                 lose("warning: core/runtime address mismatch: DYNAMIC_SPACE_START\n");
 350             }
 351 #endif
 352 #if defined(ALLOCATION_POINTER)
 353             SetSymbolValue(ALLOCATION_POINTER, (lispobj)free_pointer,0);
 354 #else
 355             dynamic_space_free_pointer = free_pointer;
 356 #endif
 357             /* For stop-and-copy GC, this will be whatever the GC was
 358              * using at the time. With GENCGC, this will always be
 359              * space 0. (We checked above that for GENCGC,
 360              * addr==DYNAMIC_SPACE_START.) */
 361             current_dynamic_space = (lispobj *)addr;
 362             break;
 363         case STATIC_CORE_SPACE_ID:
 364             if (addr != (os_vm_address_t)STATIC_SPACE_START) {
 365                 fprintf(stderr, "in core: 0x%lx - in runtime: 0x%lx\n",
 366                         (long)addr, (long)STATIC_SPACE_START);
 367                 lose("core/runtime address mismatch: STATIC_SPACE_START\n");
 368             }
 369             break;
 370         case READ_ONLY_CORE_SPACE_ID:
 371             if (addr != (os_vm_address_t)READ_ONLY_SPACE_START) {
 372                 fprintf(stderr, "in core: 0x%lx - in runtime: 0x%lx\n",
 373                         (long)addr, (long)READ_ONLY_SPACE_START);
 374                 lose("core/runtime address mismatch: READ_ONLY_SPACE_START\n");
 375             }
 376             break;
 377         default:
 378             lose("unknown space ID %ld addr 0x%lx\n", id, (long)addr);
 379         }
 380     }
 381 }
 382
 383 lispobj
 384 load_core_file(char *file, os_vm_offset_t file_offset)
 385 {
 386     void *header;
 387     word_t val, *ptr;
 388     os_vm_size_t len, remaining_len;
 389     int fd = open_binary(file, O_RDONLY);
 390     ssize_t count;
 391     lispobj initial_function = NIL;
 392
 393     FSHOW((stderr, "/entering load_core_file(%s)\n", file));
 394     if (fd < 0) {
 395         fprintf(stderr, "could not open file \"%s\"\n", file);
 396         perror("open");
 397         exit(1);
 398     }
 399
 400     lseek(fd, file_offset, SEEK_SET);
 401     header = calloc(os_vm_page_size, 1);
 402
 403     count = read(fd, header, os_vm_page_size);
 404     if (count < os_vm_page_size) {
 405         lose("premature end of core file\n");
 406     }
 407     SHOW("successfully read first page of core");
 408
 409     ptr = header;
 410     val = *ptr++;
 411
 412     if (val != CORE_MAGIC) {
 413         lose("invalid magic number in core: 0x%lx should have been 0x%x.\n",
 414              val,
 415              CORE_MAGIC);
 416     }
 417     SHOW("found CORE_MAGIC");
 418
 419     while (val != END_CORE_ENTRY_TYPE_CODE) {
 420         val = *ptr++;
 421         len = *ptr++;
 422         remaining_len = len - 2; /* (-2 to cancel the two ++ operations) */
 423         FSHOW((stderr, "/val=0x%"WORD_FMTX", remaining_len=0x%"WORD_FMTX"\n",
 424                val, remaining_len));
 425
 426         switch (val) {
 427
 428         case END_CORE_ENTRY_TYPE_CODE:
 429             SHOW("END_CORE_ENTRY_TYPE_CODE case");
 430             break;
 431
 432         case VERSION_CORE_ENTRY_TYPE_CODE:
 433             SHOW("VERSION_CORE_ENTRY_TYPE_CODE case");
 434             if (*ptr != SBCL_CORE_VERSION_INTEGER) {
 435                 lose("core file version (%d) != runtime library version (%d)\n",
 436                      *ptr,
 437                      SBCL_CORE_VERSION_INTEGER);
 438             }
 439             break;
 440
 441         case BUILD_ID_CORE_ENTRY_TYPE_CODE:
 442             SHOW("BUILD_ID_CORE_ENTRY_TYPE_CODE case");
 443             {
 444                 os_vm_size_t i;
 445
 446                 FSHOW((stderr, "build_id[]=\"%s\"\n", build_id));
 447                 FSHOW((stderr, "remaining_len = %d\n", remaining_len));
 448                 if (remaining_len != strlen((const char *)build_id))
 449                     goto losing_build_id;
 450                 for (i = 0; i < remaining_len; ++i) {
 451                     FSHOW((stderr, "ptr[%d] = char = %d, expected=%d\n",
 452                            i, ptr[i], build_id[i]));
 453                     if (ptr[i] != build_id[i])
 454                         goto losing_build_id;
 455                 }
 456                 break;
 457             losing_build_id:
 458                 /* .core files are not binary-compatible between
 459                  * builds because we can't easily detect whether the
 460                  * sources were patched between the time the
 461                  * dumping-the-.core runtime was built and the time
 462                  * that the loading-the-.core runtime was built.
 463                  *
 464                  * (We could easily detect whether version.lisp-expr
 465                  * was changed, but people experimenting with patches
 466                  * don't necessarily update version.lisp-expr.) */
 467
 468                 lose("can't load .core for different runtime, sorry\n");
 469             }
 470
 471         case NEW_DIRECTORY_CORE_ENTRY_TYPE_CODE:
 472             SHOW("NEW_DIRECTORY_CORE_ENTRY_TYPE_CODE case");
 473             process_directory(fd,
 474                               ptr,
 475 #ifndef LISP_FEATURE_ALPHA
 476                               remaining_len / (sizeof(struct ndir_entry) /
 477                                                sizeof(long)),
 478 #else
 479                               remaining_len / (sizeof(struct ndir_entry) /
 480                                                sizeof(u32)),
 481 #endif
 482                               file_offset);
 483             break;
 484
 485         case INITIAL_FUN_CORE_ENTRY_TYPE_CODE:
 486             SHOW("INITIAL_FUN_CORE_ENTRY_TYPE_CODE case");
 487             initial_function = (lispobj)*ptr;
 488             break;
 489
 490 #ifdef LISP_FEATURE_GENCGC
 491         case PAGE_TABLE_CORE_ENTRY_TYPE_CODE:
 492         {
 493             os_vm_size_t size = *ptr;
 494             os_vm_size_t fdoffset = (*(ptr+1) + 1) * (os_vm_page_size);
 495             page_index_t offset = 0;
 496             ssize_t bytes_read;
 497             word_t data[4096];
 498             word_t word;
 499             lseek(fd, fdoffset + file_offset, SEEK_SET);
 500             while ((bytes_read = read(fd, data, (size < 4096 ? size : 4096 )))
 501                     > 0)
 502             {
 503                 int i = 0;
 504                 size -= bytes_read;
 505                 while (bytes_read) {
 506                     bytes_read -= sizeof(word_t);
 507                     /* Ignore all zeroes. The size of the page table
 508                      * core entry was rounded up to os_vm_page_size
 509                      * during the save, and might now have more
 510                      * elements than the page table.
 511                      *
 512                      * The low bits of each word are allocation flags.
 513                      */
 514                     if ((word=data[i])) {
 515                         page_table[offset].region_start_offset = word & ~0x03;
 516                         page_table[offset].allocated = word & 0x03;
 517                     }
 518                     i++;
 519                     offset++;
 520                 }
 521             }
 522
 523             gencgc_partial_pickup = 1;
 524             break;
 525         }
 526 #endif
 527         default:
 528             lose("unknown core file entry: 0x%"WORD_FMTX"\n", val);
 529         }
 530
 531         ptr += remaining_len;
 532         FSHOW((stderr, "/new ptr=0x%"WORD_FTMX"\n", ptr));
 533     }
 534     SHOW("about to free(header)");
 535     free(header);
 536     SHOW("returning from load_core_file(..)");
 537     return initial_function;
 538 }
 539