gdbserver/linux-s390-ipa.cc

   1 /* GNU/Linux S/390 specific low level interface, for the in-process
   2    agent library for GDB.
   3
   4    Copyright (C) 2016-2024 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 3 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  20
  21 #include <sys/mman.h>
  22 #include "tracepoint.h"
  23 #include "linux-s390-tdesc.h"
  24 #include <elf.h>
  25 #ifdef HAVE_GETAUXVAL
  26 #include <sys/auxv.h>
  27 #endif
  28
  29 #define FT_FPR(x) (0x000 + (x) * 0x10)
  30 #define FT_VR(x) (0x000 + (x) * 0x10)
  31 #define FT_VR_L(x) (0x008 + (x) * 0x10)
  32 #define FT_GPR(x) (0x200 + (x) * 8)
  33 #define FT_GPR_U(x) (0x200 + (x) * 8)
  34 #define FT_GPR_L(x) (0x204 + (x) * 8)
  35 #define FT_GPR(x) (0x200 + (x) * 8)
  36 #define FT_ACR(x) (0x280 + (x) * 4)
  37 #define FT_PSWM 0x2c0
  38 #define FT_PSWM_U 0x2c0
  39 #define FT_PSWA 0x2c8
  40 #define FT_PSWA_L 0x2cc
  41 #define FT_FPC 0x2d0
  42
  43 /* Mappings between registers collected by the jump pad and GDB's register
  44    array layout used by regcache.
  45
  46    See linux-s390-low.c (s390_install_fast_tracepoint_jump_pad) for more
  47    details.  */
  48
  49 #ifndef __s390x__
  50
  51 /* Used for s390-linux32, s390-linux32v1, s390-linux32v2.  */
  52
  53 static const int s390_linux32_ft_collect_regmap[] = {
  54   /* 32-bit PSWA and PSWM.  */
  55   FT_PSWM_U, FT_PSWA_L,
  56   /* 32-bit GPRs (mapped to lower halves of 64-bit slots).  */
  57   FT_GPR_L (0), FT_GPR_L (1), FT_GPR_L (2), FT_GPR_L (3),
  58   FT_GPR_L (4), FT_GPR_L (5), FT_GPR_L (6), FT_GPR_L (7),
  59   FT_GPR_L (8), FT_GPR_L (9), FT_GPR_L (10), FT_GPR_L (11),
  60   FT_GPR_L (12), FT_GPR_L (13), FT_GPR_L (14), FT_GPR_L (15),
  61   /* ACRs */
  62   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
  63   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
  64   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
  65   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
  66   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
  67   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
  68   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
  69   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
  70   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
  71   /* orig_r2, last_break, system_call */
  72   -1, -1, -1,
  73 };
  74
  75 /* Used for s390-linux64, s390-linux64v1, s390-linux64v2, s390-vx-linux64.  */
  76
  77 static const int s390_linux64_ft_collect_regmap[] = {
  78   /* 32-bit PSWA and PSWM.  */
  79   FT_PSWM_U, FT_PSWA_L,
  80   /* 32-bit halves of 64-bit GPRs.  */
  81   FT_GPR_U (0), FT_GPR_L (0),
  82   FT_GPR_U (1), FT_GPR_L (1),
  83   FT_GPR_U (2), FT_GPR_L (2),
  84   FT_GPR_U (3), FT_GPR_L (3),
  85   FT_GPR_U (4), FT_GPR_L (4),
  86   FT_GPR_U (5), FT_GPR_L (5),
  87   FT_GPR_U (6), FT_GPR_L (6),
  88   FT_GPR_U (7), FT_GPR_L (7),
  89   FT_GPR_U (8), FT_GPR_L (8),
  90   FT_GPR_U (9), FT_GPR_L (9),
  91   FT_GPR_U (10), FT_GPR_L (10),
  92   FT_GPR_U (11), FT_GPR_L (11),
  93   FT_GPR_U (12), FT_GPR_L (12),
  94   FT_GPR_U (13), FT_GPR_L (13),
  95   FT_GPR_U (14), FT_GPR_L (14),
  96   FT_GPR_U (15), FT_GPR_L (15),
  97   /* ACRs */
  98   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
  99   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
 100   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
 101   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
 102   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
 103   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
 104   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
 105   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
 106   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
 107   /* orig_r2, last_break, system_call */
 108   -1, -1, -1,
 109   /* Lower halves of 128-bit VRs. */
 110   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
 111   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
 112   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
 113   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
 114   /* And the next 16 VRs.  */
 115   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
 116   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
 117   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
 118   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
 119 };
 120
 121 /* Used for s390-te-linux64, s390-tevx-linux64, and s390-gs-linux64.  */
 122
 123 static const int s390_te_linux64_ft_collect_regmap[] = {
 124   /* 32-bit PSWA and PSWM.  */
 125   FT_PSWM_U, FT_PSWA_L,
 126   /* 32-bit halves of 64-bit GPRs.  */
 127   FT_GPR_U (0), FT_GPR_L (0),
 128   FT_GPR_U (1), FT_GPR_L (1),
 129   FT_GPR_U (2), FT_GPR_L (2),
 130   FT_GPR_U (3), FT_GPR_L (3),
 131   FT_GPR_U (4), FT_GPR_L (4),
 132   FT_GPR_U (5), FT_GPR_L (5),
 133   FT_GPR_U (6), FT_GPR_L (6),
 134   FT_GPR_U (7), FT_GPR_L (7),
 135   FT_GPR_U (8), FT_GPR_L (8),
 136   FT_GPR_U (9), FT_GPR_L (9),
 137   FT_GPR_U (10), FT_GPR_L (10),
 138   FT_GPR_U (11), FT_GPR_L (11),
 139   FT_GPR_U (12), FT_GPR_L (12),
 140   FT_GPR_U (13), FT_GPR_L (13),
 141   FT_GPR_U (14), FT_GPR_L (14),
 142   FT_GPR_U (15), FT_GPR_L (15),
 143   /* ACRs */
 144   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
 145   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
 146   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
 147   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
 148   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
 149   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
 150   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
 151   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
 152   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
 153   /* orig_r2, last_break, system_call */
 154   -1, -1, -1,
 155   /* TDB */
 156   -1, -1, -1, -1,
 157   -1, -1, -1, -1,
 158   -1, -1, -1, -1,
 159   -1, -1, -1, -1,
 160   -1, -1, -1, -1,
 161   /* Lower halves of 128-bit VRs. */
 162   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
 163   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
 164   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
 165   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
 166   /* And the next 16 VRs.  */
 167   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
 168   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
 169   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
 170   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
 171 };
 172
 173 #else /* __s390x__ */
 174
 175 /* Used for s390x-linux64, s390x-linux64v1, s390x-linux64v2, s390x-vx-linux64.  */
 176
 177 static const int s390x_ft_collect_regmap[] = {
 178   /* 64-bit PSWA and PSWM.  */
 179   FT_PSWM, FT_PSWA,
 180   /* 64-bit GPRs.  */
 181   FT_GPR (0), FT_GPR (1), FT_GPR (2), FT_GPR (3),
 182   FT_GPR (4), FT_GPR (5), FT_GPR (6), FT_GPR (7),
 183   FT_GPR (8), FT_GPR (9), FT_GPR (10), FT_GPR (11),
 184   FT_GPR (12), FT_GPR (13), FT_GPR (14), FT_GPR (15),
 185   /* ACRs */
 186   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
 187   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
 188   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
 189   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
 190   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
 191   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
 192   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
 193   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
 194   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
 195   /* orig_r2, last_break, system_call */
 196   -1, -1, -1,
 197   /* Lower halves of 128-bit VRs. */
 198   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
 199   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
 200   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
 201   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
 202   /* And the next 16 VRs.  */
 203   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
 204   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
 205   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
 206   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
 207 };
 208
 209 /* Used for s390x-te-linux64, s390x-tevx-linux64, and
 210    s390x-gs-linux64.  */
 211
 212 static const int s390x_te_ft_collect_regmap[] = {
 213   /* 64-bit PSWA and PSWM.  */
 214   FT_PSWM, FT_PSWA,
 215   /* 64-bit GPRs.  */
 216   FT_GPR (0), FT_GPR (1), FT_GPR (2), FT_GPR (3),
 217   FT_GPR (4), FT_GPR (5), FT_GPR (6), FT_GPR (7),
 218   FT_GPR (8), FT_GPR (9), FT_GPR (10), FT_GPR (11),
 219   FT_GPR (12), FT_GPR (13), FT_GPR (14), FT_GPR (15),
 220   /* ACRs */
 221   FT_ACR (0), FT_ACR (1), FT_ACR (2), FT_ACR (3),
 222   FT_ACR (4), FT_ACR (5), FT_ACR (6), FT_ACR (7),
 223   FT_ACR (8), FT_ACR (9), FT_ACR (10), FT_ACR (11),
 224   FT_ACR (12), FT_ACR (13), FT_ACR (14), FT_ACR (15),
 225   /* FPRs (mapped to upper halves of 128-bit VR slots).  */
 226   FT_FPR (0), FT_FPR (1), FT_FPR (2), FT_FPR (3),
 227   FT_FPR (4), FT_FPR (5), FT_FPR (6), FT_FPR (7),
 228   FT_FPR (8), FT_FPR (9), FT_FPR (10), FT_FPR (11),
 229   FT_FPR (12), FT_FPR (13), FT_FPR (14), FT_FPR (15),
 230   /* orig_r2, last_break, system_call */
 231   -1, -1, -1,
 232   /* TDB */
 233   -1, -1, -1, -1,
 234   -1, -1, -1, -1,
 235   -1, -1, -1, -1,
 236   -1, -1, -1, -1,
 237   -1, -1, -1, -1,
 238   /* Lower halves of 128-bit VRs. */
 239   FT_VR_L (0), FT_VR_L (1), FT_VR_L (2), FT_VR_L (3),
 240   FT_VR_L (4), FT_VR_L (5), FT_VR_L (6), FT_VR_L (7),
 241   FT_VR_L (8), FT_VR_L (9), FT_VR_L (10), FT_VR_L (11),
 242   FT_VR_L (12), FT_VR_L (13), FT_VR_L (14), FT_VR_L (15),
 243   /* And the next 16 VRs.  */
 244   FT_VR (16), FT_VR (17), FT_VR (18), FT_VR (19),
 245   FT_VR (20), FT_VR (21), FT_VR (22), FT_VR (23),
 246   FT_VR (24), FT_VR (25), FT_VR (26), FT_VR (27),
 247   FT_VR (28), FT_VR (29), FT_VR (30), FT_VR (31),
 248 };
 249
 250 #endif
 251
 252 /* Initialized by get_ipa_tdesc according to the tdesc in use.  */
 253
 254 static const int *s390_regmap;
 255 static int s390_regnum;
 256
 257 /* Fill in REGCACHE with registers saved by the jump pad in BUF.  */
 258
 259 void
 260 supply_fast_tracepoint_registers (struct regcache *regcache,
 261                                   const unsigned char *buf)
 262 {
 263   int i;
 264   for (i = 0; i < s390_regnum; i++)
 265     if (s390_regmap[i] != -1)
 266       supply_register (regcache, i, ((char *) buf) + s390_regmap[i]);
 267 }
 268
 269 ULONGEST
 270 get_raw_reg (const unsigned char *raw_regs, int regnum)
 271 {
 272   int offset;
 273   if (regnum >= s390_regnum)
 274     return 0;
 275   offset = s390_regmap[regnum];
 276   if (offset == -1)
 277     return 0;
 278
 279   /* The regnums are variable, better to figure out size by FT offset.  */
 280
 281   /* 64-bit ones.  */
 282   if (offset < FT_VR(16)
 283 #ifdef __s390x__
 284       || (offset >= FT_GPR(0) && offset < FT_ACR(0))
 285       || offset == FT_PSWM
 286       || offset == FT_PSWA
 287 #endif
 288      )
 289     return *(uint64_t *) (raw_regs + offset);
 290
 291   if (offset >= FT_ACR(0 && offset < FT_PSWM)
 292       || offset == FT_FPC
 293 #ifndef __s390x__
 294       || (offset >= FT_GPR(0) && offset < FT_ACR(0))
 295       || offset == FT_PSWM_U
 296       || offset == FT_PSWA_L
 297 #endif
 298      )
 299     return *(uint32_t *) (raw_regs + offset);
 300
 301   /* This leaves 128-bit VX.  No way to return them.  */
 302   return 0;
 303 }
 304
 305 /* Return target_desc to use for IPA, given the tdesc index passed by
 306    gdbserver.  For s390, it also sets s390_regmap and s390_regnum.  */
 307
 308 const struct target_desc *
 309 get_ipa_tdesc (int idx)
 310 {
 311 #define SET_REGMAP(regmap, skip_last) \
 312         do { \
 313           s390_regmap = regmap; \
 314           s390_regnum = (sizeof regmap / sizeof regmap[0]) - skip_last; \
 315         } while(0)
 316   switch (idx)
 317     {
 318 #ifdef __s390x__
 319     case S390_TDESC_64:
 320       /* Subtract number of VX regs.  */
 321       SET_REGMAP(s390x_ft_collect_regmap, 32);
 322       return tdesc_s390x_linux64;
 323     case S390_TDESC_64V1:
 324       SET_REGMAP(s390x_ft_collect_regmap, 32);
 325       return tdesc_s390x_linux64v1;
 326     case S390_TDESC_64V2:
 327       SET_REGMAP(s390x_ft_collect_regmap, 32);
 328       return tdesc_s390x_linux64v2;
 329     case S390_TDESC_TE:
 330       SET_REGMAP(s390x_te_ft_collect_regmap, 32);
 331       return tdesc_s390x_te_linux64;
 332     case S390_TDESC_VX:
 333       SET_REGMAP(s390x_ft_collect_regmap, 0);
 334       return tdesc_s390x_vx_linux64;
 335     case S390_TDESC_TEVX:
 336       SET_REGMAP(s390x_te_ft_collect_regmap, 0);
 337       return tdesc_s390x_tevx_linux64;
 338     case S390_TDESC_GS:
 339       SET_REGMAP(s390x_te_ft_collect_regmap, 0);
 340       return tdesc_s390x_gs_linux64;
 341 #else
 342     case S390_TDESC_32:
 343       SET_REGMAP(s390_linux32_ft_collect_regmap, 0);
 344       return tdesc_s390_linux32;
 345     case S390_TDESC_32V1:
 346       SET_REGMAP(s390_linux32_ft_collect_regmap, 0);
 347       return tdesc_s390_linux32v1;
 348     case S390_TDESC_32V2:
 349       SET_REGMAP(s390_linux32_ft_collect_regmap, 0);
 350       return tdesc_s390_linux32v2;
 351     case S390_TDESC_64:
 352       SET_REGMAP(s390_linux64_ft_collect_regmap, 32);
 353       return tdesc_s390_linux64;
 354     case S390_TDESC_64V1:
 355       SET_REGMAP(s390_linux64_ft_collect_regmap, 32);
 356       return tdesc_s390_linux64v1;
 357     case S390_TDESC_64V2:
 358       SET_REGMAP(s390_linux64_ft_collect_regmap, 32);
 359       return tdesc_s390_linux64v2;
 360     case S390_TDESC_TE:
 361       SET_REGMAP(s390_te_linux64_ft_collect_regmap, 32);
 362       return tdesc_s390_te_linux64;
 363     case S390_TDESC_VX:
 364       SET_REGMAP(s390_linux64_ft_collect_regmap, 0);
 365       return tdesc_s390_vx_linux64;
 366     case S390_TDESC_TEVX:
 367       SET_REGMAP(s390_te_linux64_ft_collect_regmap, 0);
 368       return tdesc_s390_tevx_linux64;
 369     case S390_TDESC_GS:
 370       SET_REGMAP(s390_te_linux64_ft_collect_regmap, 0);
 371       return tdesc_s390_gs_linux64;
 372 #endif
 373     default:
 374       internal_error ("unknown ipa tdesc index: %d", idx);
 375 #ifdef __s390x__
 376       return tdesc_s390x_linux64;
 377 #else
 378       return tdesc_s390_linux32;
 379 #endif
 380     }
 381 }
 382
 383 /* Allocate buffer for the jump pads.  On 31-bit, JG reaches everywhere,
 384    so just allocate normally.  On 64-bit, we have +/-4GiB of reach, and
 385    the executable is usually mapped at 0x80000000 - aim for somewhere
 386    below it.  */
 387
 388 void *
 389 alloc_jump_pad_buffer (size_t size)
 390 {
 391 #ifdef __s390x__
 392   uintptr_t addr;
 393   uintptr_t exec_base = getauxval (AT_PHDR);
 394   int pagesize;
 395   void *res;
 396
 397   if (exec_base == 0)
 398     exec_base = 0x80000000;
 399
 400   pagesize = sysconf (_SC_PAGE_SIZE);
 401   if (pagesize == -1)
 402     perror_with_name ("sysconf");
 403
 404   addr = exec_base - size;
 405
 406   /* size should already be page-aligned, but this can't hurt.  */
 407   addr &= ~(pagesize - 1);
 408
 409   /* Search for a free area.  If we hit 0, we're out of luck.  */
 410   for (; addr; addr -= pagesize)
 411     {
 412       /* No MAP_FIXED - we don't want to zap someone's mapping.  */
 413       res = mmap ((void *) addr, size,
 414                   PROT_READ | PROT_WRITE | PROT_EXEC,
 415                   MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 416
 417       /* If we got what we wanted, return.  */
 418       if ((uintptr_t) res == addr)
 419         return res;
 420
 421       /* If we got a mapping, but at a wrong address, undo it.  */
 422       if (res != MAP_FAILED)
 423         munmap (res, size);
 424     }
 425
 426   return NULL;
 427 #else
 428   void *res = mmap (NULL, size, PROT_READ | PROT_WRITE | PROT_EXEC,
 429                     MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
 430
 431   if (res == MAP_FAILED)
 432     return NULL;
 433
 434   return res;
 435 #endif
 436 }
 437
 438 void
 439 initialize_low_tracepoint (void)
 440 {
 441 #ifdef __s390x__
 442   init_registers_s390x_linux64 ();
 443   init_registers_s390x_linux64v1 ();
 444   init_registers_s390x_linux64v2 ();
 445   init_registers_s390x_te_linux64 ();
 446   init_registers_s390x_vx_linux64 ();
 447   init_registers_s390x_tevx_linux64 ();
 448   init_registers_s390x_gs_linux64 ();
 449 #else
 450   init_registers_s390_linux32 ();
 451   init_registers_s390_linux32v1 ();
 452   init_registers_s390_linux32v2 ();
 453   init_registers_s390_linux64 ();
 454   init_registers_s390_linux64v1 ();
 455   init_registers_s390_linux64v2 ();
 456   init_registers_s390_te_linux64 ();
 457   init_registers_s390_vx_linux64 ();
 458   init_registers_s390_tevx_linux64 ();
 459   init_registers_s390_gs_linux64 ();
 460 #endif
 461 }