gdb/memattr.c

   1 /* Memory attributes support, for GDB.
   2
   3    Copyright (C) 2001-2023 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #include "defs.h"
  21 #include "command.h"
  22 #include "gdbcmd.h"
  23 #include "memattr.h"
  24 #include "target.h"
  25 #include "target-dcache.h"
  26 #include "value.h"
  27 #include "language.h"
  28 #include "breakpoint.h"
  29 #include "cli/cli-utils.h"
  30 #include <algorithm>
  31 #include "gdbarch.h"
  32 #include "inferior.h"
  33
  34 static std::vector<mem_region> user_mem_region_list, target_mem_region_list;
  35 static std::vector<mem_region> *mem_region_list = &target_mem_region_list;
  36 static int mem_number = 0;
  37
  38 /* If this flag is set, the memory region list should be automatically
  39    updated from the target.  If it is clear, the list is user-controlled
  40    and should be left alone.  */
  41
  42 static bool
  43 mem_use_target ()
  44 {
  45   return mem_region_list == &target_mem_region_list;
  46 }
  47
  48 /* If this flag is set, we have tried to fetch the target memory regions
  49    since the last time it was invalidated.  If that list is still
  50    empty, then the target can't supply memory regions.  */
  51 static bool target_mem_regions_valid;
  52
  53 /* If this flag is set, gdb will assume that memory ranges not
  54    specified by the memory map have type MEM_NONE, and will
  55    emit errors on all accesses to that memory.  */
  56 static bool inaccessible_by_default = true;
  57
  58 static void
  59 show_inaccessible_by_default (struct ui_file *file, int from_tty,
  60                               struct cmd_list_element *c,
  61                               const char *value)
  62 {
  63   if (inaccessible_by_default)
  64     gdb_printf (file, _("Unknown memory addresses will "
  65                         "be treated as inaccessible.\n"));
  66   else
  67     gdb_printf (file, _("Unknown memory addresses "
  68                         "will be treated as RAM.\n"));
  69 }
  70
  71 /* This function should be called before any command which would
  72    modify the memory region list.  It will handle switching from
  73    a target-provided list to a local list, if necessary.  */
  74
  75 static void
  76 require_user_regions (int from_tty)
  77 {
  78   /* If we're already using a user-provided list, nothing to do.  */
  79   if (!mem_use_target ())
  80     return;
  81
  82   /* Switch to a user-provided list (possibly a copy of the current
  83      one).  */
  84   mem_region_list = &user_mem_region_list;
  85
  86   /* If we don't have a target-provided region list yet, then
  87      no need to warn.  */
  88   if (target_mem_region_list.empty ())
  89     return;
  90
  91   /* Otherwise, let the user know how to get back.  */
  92   if (from_tty)
  93     warning (_("Switching to manual control of memory regions; use "
  94                "\"mem auto\" to fetch regions from the target again."));
  95
  96   /* And create a new list (copy of the target-supplied regions) for the user
  97      to modify.  */
  98   user_mem_region_list = target_mem_region_list;
  99 }
 100
 101 /* This function should be called before any command which would
 102    read the memory region list, other than those which call
 103    require_user_regions.  It will handle fetching the
 104    target-provided list, if necessary.  */
 105
 106 static void
 107 require_target_regions (void)
 108 {
 109   if (mem_use_target () && !target_mem_regions_valid)
 110     {
 111       target_mem_regions_valid = true;
 112       target_mem_region_list = target_memory_map ();
 113     }
 114 }
 115
 116 /* Create a new user-defined memory region.  */
 117
 118 static void
 119 create_user_mem_region (CORE_ADDR lo, CORE_ADDR hi,
 120                         const mem_attrib &attrib)
 121 {
 122   /* lo == hi is a useless empty region.  */
 123   if (lo >= hi && hi != 0)
 124     {
 125       gdb_printf (_("invalid memory region: low >= high\n"));
 126       return;
 127     }
 128
 129   mem_region newobj (lo, hi, attrib);
 130
 131   auto it = std::lower_bound (user_mem_region_list.begin (),
 132                               user_mem_region_list.end (),
 133                               newobj);
 134   int ix = std::distance (user_mem_region_list.begin (), it);
 135
 136   /* Check for an overlapping memory region.  We only need to check
 137      in the vincinity - at most one before and one after the
 138      insertion point.  */
 139   for (int i = ix - 1; i < ix + 1; i++)
 140     {
 141       if (i < 0)
 142         continue;
 143       if (i >= user_mem_region_list.size ())
 144         continue;
 145
 146       mem_region &n = user_mem_region_list[i];
 147
 148       if ((lo >= n.lo && (lo < n.hi || n.hi == 0))
 149           || (hi > n.lo && (hi <= n.hi || n.hi == 0))
 150           || (lo <= n.lo && ((hi >= n.hi && n.hi != 0) || hi == 0)))
 151         {
 152           gdb_printf (_("overlapping memory region\n"));
 153           return;
 154         }
 155     }
 156
 157   newobj.number = ++mem_number;
 158   user_mem_region_list.insert (it, newobj);
 159 }
 160
 161 /* Look up the memory region corresponding to ADDR.  */
 162
 163 struct mem_region *
 164 lookup_mem_region (CORE_ADDR addr)
 165 {
 166   static struct mem_region region (0, 0);
 167   CORE_ADDR lo;
 168   CORE_ADDR hi;
 169
 170   require_target_regions ();
 171
 172   /* First we initialize LO and HI so that they describe the entire
 173      memory space.  As we process the memory region chain, they are
 174      redefined to describe the minimal region containing ADDR.  LO
 175      and HI are used in the case where no memory region is defined
 176      that contains ADDR.  If a memory region is disabled, it is
 177      treated as if it does not exist.  The initial values for LO
 178      and HI represent the bottom and top of memory.  */
 179
 180   lo = 0;
 181   hi = 0;
 182
 183   /* Either find memory range containing ADDR, or set LO and HI
 184      to the nearest boundaries of an existing memory range.
 185
 186      If we ever want to support a huge list of memory regions, this
 187      check should be replaced with a binary search (probably using
 188      VEC_lower_bound).  */
 189   for (mem_region &m : *mem_region_list)
 190     {
 191       if (m.enabled_p == 1)
 192         {
 193           /* If the address is in the memory region, return that
 194              memory range.  */
 195           if (addr >= m.lo && (addr < m.hi || m.hi == 0))
 196             return &m;
 197
 198           /* This (correctly) won't match if m->hi == 0, representing
 199              the top of the address space, because CORE_ADDR is unsigned;
 200              no value of LO is less than zero.  */
 201           if (addr >= m.hi && lo < m.hi)
 202             lo = m.hi;
 203
 204           /* This will never set HI to zero; if we're here and ADDR
 205              is at or below M, and the region starts at zero, then ADDR
 206              would have been in the region.  */
 207           if (addr <= m.lo && (hi == 0 || hi > m.lo))
 208             hi = m.lo;
 209         }
 210     }
 211
 212   /* Because no region was found, we must cons up one based on what
 213      was learned above.  */
 214   region.lo = lo;
 215   region.hi = hi;
 216
 217   /* When no memory map is defined at all, we always return
 218      'default_mem_attrib', so that we do not make all memory
 219      inaccessible for targets that don't provide a memory map.  */
 220   if (inaccessible_by_default && !mem_region_list->empty ())
 221     region.attrib = mem_attrib::unknown ();
 222   else
 223     region.attrib = mem_attrib ();
 224
 225   return &region;
 226 }
 227
 228 /* Invalidate any memory regions fetched from the target.  */
 229
 230 void
 231 invalidate_target_mem_regions (void)
 232 {
 233   if (!target_mem_regions_valid)
 234     return;
 235
 236   target_mem_regions_valid = false;
 237   target_mem_region_list.clear ();
 238 }
 239
 240 /* Clear user-defined memory region list.  */
 241
 242 static void
 243 user_mem_clear (void)
 244 {
 245   user_mem_region_list.clear ();
 246 }
 247 \f
 248
 249 static void
 250 mem_command (const char *args, int from_tty)
 251 {
 252   CORE_ADDR lo, hi;
 253
 254   if (!args)
 255     error_no_arg (_("No mem"));
 256
 257   /* For "mem auto", switch back to using a target provided list.  */
 258   if (strcmp (args, "auto") == 0)
 259     {
 260       if (mem_use_target ())
 261         return;
 262
 263       user_mem_clear ();
 264       mem_region_list = &target_mem_region_list;
 265
 266       return;
 267     }
 268
 269   require_user_regions (from_tty);
 270
 271   std::string tok = extract_arg (&args);
 272   if (tok == "")
 273     error (_("no lo address"));
 274   lo = parse_and_eval_address (tok.c_str ());
 275
 276   tok = extract_arg (&args);
 277   if (tok == "")
 278     error (_("no hi address"));
 279   hi = parse_and_eval_address (tok.c_str ());
 280
 281   mem_attrib attrib;
 282   while ((tok = extract_arg (&args)) != "")
 283     {
 284       if (tok == "rw")
 285         attrib.mode = MEM_RW;
 286       else if (tok == "ro")
 287         attrib.mode = MEM_RO;
 288       else if (tok == "wo")
 289         attrib.mode = MEM_WO;
 290
 291       else if (tok == "8")
 292         attrib.width = MEM_WIDTH_8;
 293       else if (tok == "16")
 294         {
 295           if ((lo % 2 != 0) || (hi % 2 != 0))
 296             error (_("region bounds not 16 bit aligned"));
 297           attrib.width = MEM_WIDTH_16;
 298         }
 299       else if (tok == "32")
 300         {
 301           if ((lo % 4 != 0) || (hi % 4 != 0))
 302             error (_("region bounds not 32 bit aligned"));
 303           attrib.width = MEM_WIDTH_32;
 304         }
 305       else if (tok == "64")
 306         {
 307           if ((lo % 8 != 0) || (hi % 8 != 0))
 308             error (_("region bounds not 64 bit aligned"));
 309           attrib.width = MEM_WIDTH_64;
 310         }
 311
 312 #if 0
 313       else if (tok == "hwbreak")
 314         attrib.hwbreak = 1;
 315       else if (tok == "swbreak")
 316         attrib.hwbreak = 0;
 317 #endif
 318
 319       else if (tok == "cache")
 320         attrib.cache = 1;
 321       else if (tok == "nocache")
 322         attrib.cache = 0;
 323
 324 #if 0
 325       else if (tok == "verify")
 326         attrib.verify = 1;
 327       else if (tok == "noverify")
 328         attrib.verify = 0;
 329 #endif
 330
 331       else
 332         error (_("unknown attribute: %s"), tok.c_str ());
 333     }
 334
 335   create_user_mem_region (lo, hi, attrib);
 336 }
 337 \f
 338
 339 static void
 340 info_mem_command (const char *args, int from_tty)
 341 {
 342   if (mem_use_target ())
 343     gdb_printf (_("Using memory regions provided by the target.\n"));
 344   else
 345     gdb_printf (_("Using user-defined memory regions.\n"));
 346
 347   require_target_regions ();
 348
 349   if (mem_region_list->empty ())
 350     {
 351       gdb_printf (_("There are no memory regions defined.\n"));
 352       return;
 353     }
 354
 355   gdb_printf ("Num ");
 356   gdb_printf ("Enb ");
 357   gdb_printf ("Low Addr   ");
 358   if (gdbarch_addr_bit (current_inferior ()->arch ()) > 32)
 359     gdb_printf ("        ");
 360   gdb_printf ("High Addr  ");
 361   if (gdbarch_addr_bit (current_inferior ()->arch ()) > 32)
 362     gdb_printf ("        ");
 363   gdb_printf ("Attrs ");
 364   gdb_printf ("\n");
 365
 366   for (const mem_region &m : *mem_region_list)
 367     {
 368       const char *tmp;
 369
 370       gdb_printf ("%-3d %-3c\t",
 371                   m.number,
 372                   m.enabled_p ? 'y' : 'n');
 373       if (gdbarch_addr_bit (current_inferior ()->arch ()) <= 32)
 374         tmp = hex_string_custom (m.lo, 8);
 375       else
 376         tmp = hex_string_custom (m.lo, 16);
 377
 378       gdb_printf ("%s ", tmp);
 379
 380       if (gdbarch_addr_bit (current_inferior ()->arch ()) <= 32)
 381         {
 382           if (m.hi == 0)
 383             tmp = "0x100000000";
 384           else
 385             tmp = hex_string_custom (m.hi, 8);
 386         }
 387       else
 388         {
 389           if (m.hi == 0)
 390             tmp = "0x10000000000000000";
 391           else
 392             tmp = hex_string_custom (m.hi, 16);
 393         }
 394
 395       gdb_printf ("%s ", tmp);
 396
 397       /* Print a token for each attribute.
 398
 399        * FIXME: Should we output a comma after each token?  It may
 400        * make it easier for users to read, but we'd lose the ability
 401        * to cut-and-paste the list of attributes when defining a new
 402        * region.  Perhaps that is not important.
 403        *
 404        * FIXME: If more attributes are added to GDB, the output may
 405        * become cluttered and difficult for users to read.  At that
 406        * time, we may want to consider printing tokens only if they
 407        * are different from the default attribute.  */
 408
 409       switch (m.attrib.mode)
 410         {
 411         case MEM_RW:
 412           gdb_printf ("rw ");
 413           break;
 414         case MEM_RO:
 415           gdb_printf ("ro ");
 416           break;
 417         case MEM_WO:
 418           gdb_printf ("wo ");
 419           break;
 420         case MEM_FLASH:
 421           gdb_printf ("flash blocksize 0x%x ", m.attrib.blocksize);
 422           break;
 423         }
 424
 425       switch (m.attrib.width)
 426         {
 427         case MEM_WIDTH_8:
 428           gdb_printf ("8 ");
 429           break;
 430         case MEM_WIDTH_16:
 431           gdb_printf ("16 ");
 432           break;
 433         case MEM_WIDTH_32:
 434           gdb_printf ("32 ");
 435           break;
 436         case MEM_WIDTH_64:
 437           gdb_printf ("64 ");
 438           break;
 439         case MEM_WIDTH_UNSPECIFIED:
 440           break;
 441         }
 442
 443 #if 0
 444       if (attrib->hwbreak)
 445         gdb_printf ("hwbreak");
 446       else
 447         gdb_printf ("swbreak");
 448 #endif
 449
 450       if (m.attrib.cache)
 451         gdb_printf ("cache ");
 452       else
 453         gdb_printf ("nocache ");
 454
 455 #if 0
 456       if (attrib->verify)
 457         gdb_printf ("verify ");
 458       else
 459         gdb_printf ("noverify ");
 460 #endif
 461
 462       gdb_printf ("\n");
 463     }
 464 }
 465 \f
 466
 467 /* Enable the memory region number NUM.  */
 468
 469 static void
 470 mem_enable (int num)
 471 {
 472   for (mem_region &m : *mem_region_list)
 473     if (m.number == num)
 474       {
 475         m.enabled_p = 1;
 476         return;
 477       }
 478   gdb_printf (_("No memory region number %d.\n"), num);
 479 }
 480
 481 static void
 482 enable_mem_command (const char *args, int from_tty)
 483 {
 484   require_user_regions (from_tty);
 485
 486   target_dcache_invalidate ();
 487
 488   if (args == NULL || *args == '\0')
 489     { /* Enable all mem regions.  */
 490       for (mem_region &m : *mem_region_list)
 491         m.enabled_p = 1;
 492     }
 493   else
 494     {
 495       number_or_range_parser parser (args);
 496       while (!parser.finished ())
 497         {
 498           int num = parser.get_number ();
 499           mem_enable (num);
 500         }
 501     }
 502 }
 503 \f
 504
 505 /* Disable the memory region number NUM.  */
 506
 507 static void
 508 mem_disable (int num)
 509 {
 510   for (mem_region &m : *mem_region_list)
 511     if (m.number == num)
 512       {
 513         m.enabled_p = 0;
 514         return;
 515       }
 516   gdb_printf (_("No memory region number %d.\n"), num);
 517 }
 518
 519 static void
 520 disable_mem_command (const char *args, int from_tty)
 521 {
 522   require_user_regions (from_tty);
 523
 524   target_dcache_invalidate ();
 525
 526   if (args == NULL || *args == '\0')
 527     {
 528       for (mem_region &m : *mem_region_list)
 529         m.enabled_p = false;
 530     }
 531   else
 532     {
 533       number_or_range_parser parser (args);
 534       while (!parser.finished ())
 535         {
 536           int num = parser.get_number ();
 537           mem_disable (num);
 538         }
 539     }
 540 }
 541
 542 /* Delete the memory region number NUM.  */
 543
 544 static void
 545 mem_delete (int num)
 546 {
 547   if (!mem_region_list)
 548     {
 549       gdb_printf (_("No memory region number %d.\n"), num);
 550       return;
 551     }
 552
 553   auto it = std::remove_if (mem_region_list->begin (), mem_region_list->end (),
 554                             [num] (const mem_region &m)
 555     {
 556       return m.number == num;
 557     });
 558
 559   if (it != mem_region_list->end ())
 560     mem_region_list->erase (it);
 561   else
 562     gdb_printf (_("No memory region number %d.\n"), num);
 563 }
 564
 565 static void
 566 delete_mem_command (const char *args, int from_tty)
 567 {
 568   require_user_regions (from_tty);
 569
 570   target_dcache_invalidate ();
 571
 572   if (args == NULL || *args == '\0')
 573     {
 574       if (query (_("Delete all memory regions? ")))
 575         user_mem_clear ();
 576       dont_repeat ();
 577       return;
 578     }
 579
 580   number_or_range_parser parser (args);
 581   while (!parser.finished ())
 582     {
 583       int num = parser.get_number ();
 584       mem_delete (num);
 585     }
 586
 587   dont_repeat ();
 588 }
 589
 590 static struct cmd_list_element *mem_set_cmdlist;
 591 static struct cmd_list_element *mem_show_cmdlist;
 592
 593 void _initialize_mem ();
 594 void
 595 _initialize_mem ()
 596 {
 597   add_com ("mem", class_vars, mem_command, _("\
 598 Define attributes for memory region or reset memory region handling to "
 599 "target-based.\n\
 600 Usage: mem auto\n\
 601        mem LOW HIGH [MODE WIDTH CACHE],\n\
 602 where MODE  may be rw (read/write), ro (read-only) or wo (write-only),\n\
 603       WIDTH may be 8, 16, 32, or 64, and\n\
 604       CACHE may be cache or nocache"));
 605
 606   add_cmd ("mem", class_vars, enable_mem_command, _("\
 607 Enable memory region.\n\
 608 Arguments are the IDs of the memory regions to enable.\n\
 609 Usage: enable mem [ID]...\n\
 610 Do \"info mem\" to see current list of IDs."), &enablelist);
 611
 612   add_cmd ("mem", class_vars, disable_mem_command, _("\
 613 Disable memory region.\n\
 614 Arguments are the IDs of the memory regions to disable.\n\
 615 Usage: disable mem [ID]...\n\
 616 Do \"info mem\" to see current list of IDs."), &disablelist);
 617
 618   add_cmd ("mem", class_vars, delete_mem_command, _("\
 619 Delete memory region.\n\
 620 Arguments are the IDs of the memory regions to delete.\n\
 621 Usage: delete mem [ID]...\n\
 622 Do \"info mem\" to see current list of IDs."), &deletelist);
 623
 624   add_info ("mem", info_mem_command,
 625             _("Memory region attributes."));
 626
 627   add_setshow_prefix_cmd ("mem", class_vars,
 628                           _("Memory regions settings."),
 629                           _("Memory regions settings."),
 630                           &mem_set_cmdlist, &mem_show_cmdlist,
 631                           &setlist, &showlist);
 632
 633   add_setshow_boolean_cmd ("inaccessible-by-default", no_class,
 634                                   &inaccessible_by_default, _("\
 635 Set handling of unknown memory regions."), _("\
 636 Show handling of unknown memory regions."), _("\
 637 If on, and some memory map is defined, debugger will emit errors on\n\
 638 accesses to memory not defined in the memory map. If off, accesses to all\n\
 639 memory addresses will be allowed."),
 640                                 NULL,
 641                                 show_inaccessible_by_default,
 642                                 &mem_set_cmdlist,
 643                                 &mem_show_cmdlist);
 644 }