gdb/gdbserver/linux-s390-low.c

   1 /* GNU/Linux S/390 specific low level interface, for the remote server
   2    for GDB.
   3    Copyright (C) 2001-2014 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 /* This file is used for both 31-bit and 64-bit S/390 systems.  */
  21
  22 #include "server.h"
  23 #include "linux-low.h"
  24 #include "elf/common.h"
  25
  26 #include <asm/ptrace.h>
  27 #include <sys/ptrace.h>
  28 #include <sys/uio.h>
  29 #include <elf.h>
  30
  31 #ifndef HWCAP_S390_HIGH_GPRS
  32 #define HWCAP_S390_HIGH_GPRS 512
  33 #endif
  34
  35 #ifndef HWCAP_S390_TE
  36 #define HWCAP_S390_TE 1024
  37 #endif
  38
  39 #ifndef PTRACE_GETREGSET
  40 #define PTRACE_GETREGSET 0x4204
  41 #endif
  42
  43 #ifndef PTRACE_SETREGSET
  44 #define PTRACE_SETREGSET 0x4205
  45 #endif
  46
  47 /* Defined in auto-generated file s390-linux32.c.  */
  48 void init_registers_s390_linux32 (void);
  49 extern const struct target_desc *tdesc_s390_linux32;
  50
  51 /* Defined in auto-generated file s390-linux32v1.c.  */
  52 void init_registers_s390_linux32v1 (void);
  53 extern const struct target_desc *tdesc_s390_linux32v1;
  54
  55 /* Defined in auto-generated file s390-linux32v2.c.  */
  56 void init_registers_s390_linux32v2 (void);
  57 extern const struct target_desc *tdesc_s390_linux32v2;
  58
  59 /* Defined in auto-generated file s390-linux64.c.  */
  60 void init_registers_s390_linux64 (void);
  61 extern const struct target_desc *tdesc_s390_linux64;
  62
  63 /* Defined in auto-generated file s390-linux64v1.c.  */
  64 void init_registers_s390_linux64v1 (void);
  65 extern const struct target_desc *tdesc_s390_linux64v1;
  66
  67 /* Defined in auto-generated file s390-linux64v2.c.  */
  68 void init_registers_s390_linux64v2 (void);
  69 extern const struct target_desc *tdesc_s390_linux64v2;
  70
  71 /* Defined in auto-generated file s390-te-linux64.c.  */
  72 void init_registers_s390_te_linux64 (void);
  73 extern const struct target_desc *tdesc_s390_te_linux64;
  74
  75 /* Defined in auto-generated file s390x-linux64.c.  */
  76 void init_registers_s390x_linux64 (void);
  77 extern const struct target_desc *tdesc_s390x_linux64;
  78
  79 /* Defined in auto-generated file s390x-linux64v1.c.  */
  80 void init_registers_s390x_linux64v1 (void);
  81 extern const struct target_desc *tdesc_s390x_linux64v1;
  82
  83 /* Defined in auto-generated file s390x-linux64v2.c.  */
  84 void init_registers_s390x_linux64v2 (void);
  85 extern const struct target_desc *tdesc_s390x_linux64v2;
  86
  87 /* Defined in auto-generated file s390x-te-linux64.c.  */
  88 void init_registers_s390x_te_linux64 (void);
  89 extern const struct target_desc *tdesc_s390x_te_linux64;
  90
  91 #define s390_num_regs 52
  92
  93 static int s390_regmap[] = {
  94   PT_PSWMASK, PT_PSWADDR,
  95
  96   PT_GPR0, PT_GPR1, PT_GPR2, PT_GPR3,
  97   PT_GPR4, PT_GPR5, PT_GPR6, PT_GPR7,
  98   PT_GPR8, PT_GPR9, PT_GPR10, PT_GPR11,
  99   PT_GPR12, PT_GPR13, PT_GPR14, PT_GPR15,
 100
 101   PT_ACR0, PT_ACR1, PT_ACR2, PT_ACR3,
 102   PT_ACR4, PT_ACR5, PT_ACR6, PT_ACR7,
 103   PT_ACR8, PT_ACR9, PT_ACR10, PT_ACR11,
 104   PT_ACR12, PT_ACR13, PT_ACR14, PT_ACR15,
 105
 106   PT_FPC,
 107
 108 #ifndef __s390x__
 109   PT_FPR0_HI, PT_FPR1_HI, PT_FPR2_HI, PT_FPR3_HI,
 110   PT_FPR4_HI, PT_FPR5_HI, PT_FPR6_HI, PT_FPR7_HI,
 111   PT_FPR8_HI, PT_FPR9_HI, PT_FPR10_HI, PT_FPR11_HI,
 112   PT_FPR12_HI, PT_FPR13_HI, PT_FPR14_HI, PT_FPR15_HI,
 113 #else
 114   PT_FPR0, PT_FPR1, PT_FPR2, PT_FPR3,
 115   PT_FPR4, PT_FPR5, PT_FPR6, PT_FPR7,
 116   PT_FPR8, PT_FPR9, PT_FPR10, PT_FPR11,
 117   PT_FPR12, PT_FPR13, PT_FPR14, PT_FPR15,
 118 #endif
 119
 120   PT_ORIGGPR2,
 121 };
 122
 123 #ifdef __s390x__
 124 #define s390_num_regs_3264 68
 125
 126 static int s390_regmap_3264[] = {
 127   PT_PSWMASK, PT_PSWADDR,
 128
 129   PT_GPR0, PT_GPR0, PT_GPR1, PT_GPR1,
 130   PT_GPR2, PT_GPR2, PT_GPR3, PT_GPR3,
 131   PT_GPR4, PT_GPR4, PT_GPR5, PT_GPR5,
 132   PT_GPR6, PT_GPR6, PT_GPR7, PT_GPR7,
 133   PT_GPR8, PT_GPR8, PT_GPR9, PT_GPR9,
 134   PT_GPR10, PT_GPR10, PT_GPR11, PT_GPR11,
 135   PT_GPR12, PT_GPR12, PT_GPR13, PT_GPR13,
 136   PT_GPR14, PT_GPR14, PT_GPR15, PT_GPR15,
 137
 138   PT_ACR0, PT_ACR1, PT_ACR2, PT_ACR3,
 139   PT_ACR4, PT_ACR5, PT_ACR6, PT_ACR7,
 140   PT_ACR8, PT_ACR9, PT_ACR10, PT_ACR11,
 141   PT_ACR12, PT_ACR13, PT_ACR14, PT_ACR15,
 142
 143   PT_FPC,
 144
 145   PT_FPR0, PT_FPR1, PT_FPR2, PT_FPR3,
 146   PT_FPR4, PT_FPR5, PT_FPR6, PT_FPR7,
 147   PT_FPR8, PT_FPR9, PT_FPR10, PT_FPR11,
 148   PT_FPR12, PT_FPR13, PT_FPR14, PT_FPR15,
 149
 150   PT_ORIGGPR2,
 151 };
 152 #endif
 153
 154
 155 static int
 156 s390_cannot_fetch_register (int regno)
 157 {
 158   return 0;
 159 }
 160
 161 static int
 162 s390_cannot_store_register (int regno)
 163 {
 164   return 0;
 165 }
 166
 167 static void
 168 s390_collect_ptrace_register (struct regcache *regcache, int regno, char *buf)
 169 {
 170   int size = register_size (regcache->tdesc, regno);
 171   if (size < sizeof (long))
 172     {
 173       const struct regs_info *regs_info = (*the_low_target.regs_info) ();
 174       struct usrregs_info *usr = regs_info->usrregs;
 175       int regaddr = usr->regmap[regno];
 176
 177       memset (buf, 0, sizeof (long));
 178
 179       if ((regno ^ 1) < usr->num_regs
 180           && usr->regmap[regno ^ 1] == regaddr)
 181         {
 182           collect_register (regcache, regno & ~1, buf);
 183           collect_register (regcache, (regno & ~1) + 1,
 184                             buf + sizeof (long) - size);
 185         }
 186       else if (regaddr == PT_PSWMASK)
 187         {
 188           /* Convert 4-byte PSW mask to 8 bytes by clearing bit 12 and copying
 189              the basic addressing mode bit from the PSW address.  */
 190           char *addr = alloca (register_size (regcache->tdesc, regno ^ 1));
 191           collect_register (regcache, regno, buf);
 192           collect_register (regcache, regno ^ 1, addr);
 193           buf[1] &= ~0x8;
 194           buf[size] |= (addr[0] & 0x80);
 195         }
 196       else if (regaddr == PT_PSWADDR)
 197         {
 198           /* Convert 4-byte PSW address to 8 bytes by clearing the addressing
 199              mode bit (which gets copied to the PSW mask instead).  */
 200           collect_register (regcache, regno, buf + sizeof (long) - size);
 201           buf[sizeof (long) - size] &= ~0x80;
 202         }
 203       else if ((regaddr >= PT_GPR0 && regaddr <= PT_GPR15)
 204                || regaddr == PT_ORIGGPR2)
 205         collect_register (regcache, regno, buf + sizeof (long) - size);
 206       else
 207         collect_register (regcache, regno, buf);
 208     }
 209   else
 210     collect_register (regcache, regno, buf);
 211 }
 212
 213 static void
 214 s390_supply_ptrace_register (struct regcache *regcache,
 215                              int regno, const char *buf)
 216 {
 217   int size = register_size (regcache->tdesc, regno);
 218   if (size < sizeof (long))
 219     {
 220       const struct regs_info *regs_info = (*the_low_target.regs_info) ();
 221       struct usrregs_info *usr = regs_info->usrregs;
 222       int regaddr = usr->regmap[regno];
 223
 224       if ((regno ^ 1) < usr->num_regs
 225           && usr->regmap[regno ^ 1] == regaddr)
 226         {
 227           supply_register (regcache, regno & ~1, buf);
 228           supply_register (regcache, (regno & ~1) + 1,
 229                            buf + sizeof (long) - size);
 230         }
 231       else if (regaddr == PT_PSWMASK)
 232         {
 233           /* Convert 8-byte PSW mask to 4 bytes by setting bit 12 and copying
 234              the basic addressing mode into the PSW address.  */
 235           char *mask = alloca (size);
 236           char *addr = alloca (register_size (regcache->tdesc, regno ^ 1));
 237           memcpy (mask, buf, size);
 238           mask[1] |= 0x8;
 239           supply_register (regcache, regno, mask);
 240
 241           collect_register (regcache, regno ^ 1, addr);
 242           addr[0] &= ~0x80;
 243           addr[0] |= (buf[size] & 0x80);
 244           supply_register (regcache, regno ^ 1, addr);
 245         }
 246       else if (regaddr == PT_PSWADDR)
 247         {
 248           /* Convert 8-byte PSW address to 4 bytes by truncating, but
 249              keeping the addressing mode bit (which was set from the mask).  */
 250           char *addr = alloca (size);
 251           char amode;
 252           collect_register (regcache, regno, addr);
 253           amode = addr[0] & 0x80;
 254           memcpy (addr, buf + sizeof (long) - size, size);
 255           addr[0] &= ~0x80;
 256           addr[0] |= amode;
 257           supply_register (regcache, regno, addr);
 258         }
 259       else if ((regaddr >= PT_GPR0 && regaddr <= PT_GPR15)
 260                || regaddr == PT_ORIGGPR2)
 261         supply_register (regcache, regno, buf + sizeof (long) - size);
 262       else
 263         supply_register (regcache, regno, buf);
 264     }
 265   else
 266     supply_register (regcache, regno, buf);
 267 }
 268
 269 /* Provide only a fill function for the general register set.  ps_lgetregs
 270    will use this for NPTL support.  */
 271
 272 static void
 273 s390_fill_gregset (struct regcache *regcache, void *buf)
 274 {
 275   int i;
 276   const struct regs_info *regs_info = (*the_low_target.regs_info) ();
 277   struct usrregs_info *usr = regs_info->usrregs;
 278
 279   for (i = 0; i < usr->num_regs; i++)
 280     {
 281       if (usr->regmap[i] < PT_PSWMASK
 282           || usr->regmap[i] > PT_ACR15)
 283         continue;
 284
 285       s390_collect_ptrace_register (regcache, i,
 286                                     (char *) buf + usr->regmap[i]);
 287     }
 288 }
 289
 290 /* Fill and store functions for extended register sets.  */
 291
 292 static void
 293 s390_fill_last_break (struct regcache *regcache, void *buf)
 294 {
 295   /* Last break address is read-only.  */
 296 }
 297
 298 static void
 299 s390_store_last_break (struct regcache *regcache, const void *buf)
 300 {
 301   const char *p;
 302
 303   p = (const char *) buf + 8 - register_size (regcache->tdesc, 0);
 304   supply_register_by_name (regcache, "last_break", p);
 305 }
 306
 307 static void
 308 s390_fill_system_call (struct regcache *regcache, void *buf)
 309 {
 310   collect_register_by_name (regcache, "system_call", buf);
 311 }
 312
 313 static void
 314 s390_store_system_call (struct regcache *regcache, const void *buf)
 315 {
 316   supply_register_by_name (regcache, "system_call", buf);
 317 }
 318
 319 static struct regset_info s390_regsets[] = {
 320   { 0, 0, 0, 0, GENERAL_REGS, s390_fill_gregset, NULL },
 321   /* Last break address is read-only; do not attempt PTRACE_SETREGSET.  */
 322   { PTRACE_GETREGSET, PTRACE_GETREGSET, NT_S390_LAST_BREAK, 0,
 323     EXTENDED_REGS, s390_fill_last_break, s390_store_last_break },
 324   { PTRACE_GETREGSET, PTRACE_SETREGSET, NT_S390_SYSTEM_CALL, 0,
 325     EXTENDED_REGS, s390_fill_system_call, s390_store_system_call },
 326   { 0, 0, 0, -1, -1, NULL, NULL }
 327 };
 328
 329
 330 static const unsigned char s390_breakpoint[] = { 0, 1 };
 331 #define s390_breakpoint_len 2
 332
 333 static CORE_ADDR
 334 s390_get_pc (struct regcache *regcache)
 335 {
 336   if (register_size (regcache->tdesc, 0) == 4)
 337     {
 338       unsigned int pswa;
 339       collect_register_by_name (regcache, "pswa", &pswa);
 340       return pswa & 0x7fffffff;
 341     }
 342   else
 343     {
 344       unsigned long pc;
 345       collect_register_by_name (regcache, "pswa", &pc);
 346       return pc;
 347     }
 348 }
 349
 350 static void
 351 s390_set_pc (struct regcache *regcache, CORE_ADDR newpc)
 352 {
 353   if (register_size (regcache->tdesc, 0) == 4)
 354     {
 355       unsigned int pswa;
 356       collect_register_by_name (regcache, "pswa", &pswa);
 357       pswa = (pswa & 0x80000000) | (newpc & 0x7fffffff);
 358       supply_register_by_name (regcache, "pswa", &pswa);
 359     }
 360   else
 361     {
 362       unsigned long pc = newpc;
 363       supply_register_by_name (regcache, "pswa", &pc);
 364     }
 365 }
 366
 367 #ifdef __s390x__
 368 static unsigned long
 369 s390_get_hwcap (const struct target_desc *tdesc)
 370 {
 371   int wordsize = register_size (tdesc, 0);
 372   unsigned char *data = alloca (2 * wordsize);
 373   int offset = 0;
 374
 375   while ((*the_target->read_auxv) (offset, data, 2 * wordsize) == 2 * wordsize)
 376     {
 377       if (wordsize == 4)
 378         {
 379           unsigned int *data_p = (unsigned int *)data;
 380           if (data_p[0] == AT_HWCAP)
 381             return data_p[1];
 382         }
 383       else
 384         {
 385           unsigned long *data_p = (unsigned long *)data;
 386           if (data_p[0] == AT_HWCAP)
 387             return data_p[1];
 388         }
 389
 390       offset += 2 * wordsize;
 391     }
 392
 393   return 0;
 394 }
 395 #endif
 396
 397 static int
 398 s390_check_regset (int pid, int regset, int regsize)
 399 {
 400   gdb_byte *buf = alloca (regsize);
 401   struct iovec iov;
 402
 403   iov.iov_base = buf;
 404   iov.iov_len = regsize;
 405
 406   if (ptrace (PTRACE_GETREGSET, pid, (long) regset, (long) &iov) >= 0
 407       || errno == ENODATA)
 408     return 1;
 409   return 0;
 410 }
 411
 412 #ifdef __s390x__
 413 /* For a 31-bit inferior, whether the kernel supports using the full
 414    64-bit GPRs.  */
 415 static int have_hwcap_s390_high_gprs = 0;
 416 #endif
 417
 418 static void
 419 s390_arch_setup (void)
 420 {
 421   const struct target_desc *tdesc;
 422   struct regset_info *regset;
 423
 424   /* Check whether the kernel supports extra register sets.  */
 425   int pid = pid_of (current_inferior);
 426   int have_regset_last_break
 427     = s390_check_regset (pid, NT_S390_LAST_BREAK, 8);
 428   int have_regset_system_call
 429     = s390_check_regset (pid, NT_S390_SYSTEM_CALL, 4);
 430   int have_regset_tdb = s390_check_regset (pid, NT_S390_TDB, 256);
 431
 432   /* Assume 31-bit inferior process.  */
 433   if (have_regset_system_call)
 434     tdesc = tdesc_s390_linux32v2;
 435   else if (have_regset_last_break)
 436     tdesc = tdesc_s390_linux32v1;
 437   else
 438     tdesc = tdesc_s390_linux32;
 439
 440   /* On a 64-bit host, check the low bit of the (31-bit) PSWM
 441      -- if this is one, we actually have a 64-bit inferior.  */
 442 #ifdef __s390x__
 443   {
 444     unsigned int pswm;
 445     struct regcache *regcache = new_register_cache (tdesc);
 446
 447     fetch_inferior_registers (regcache, find_regno (tdesc, "pswm"));
 448     collect_register_by_name (regcache, "pswm", &pswm);
 449     free_register_cache (regcache);
 450
 451     if (pswm & 1)
 452       {
 453         if (have_regset_tdb)
 454           have_regset_tdb =
 455             (s390_get_hwcap (tdesc_s390x_linux64v2) & HWCAP_S390_TE) != 0;
 456
 457         if (have_regset_tdb)
 458           tdesc = tdesc_s390x_te_linux64;
 459         else if (have_regset_system_call)
 460           tdesc = tdesc_s390x_linux64v2;
 461         else if (have_regset_last_break)
 462           tdesc = tdesc_s390x_linux64v1;
 463         else
 464           tdesc = tdesc_s390x_linux64;
 465       }
 466
 467     /* For a 31-bit inferior, check whether the kernel supports
 468        using the full 64-bit GPRs.  */
 469     else if (s390_get_hwcap (tdesc) & HWCAP_S390_HIGH_GPRS)
 470       {
 471         have_hwcap_s390_high_gprs = 1;
 472         if (have_regset_tdb)
 473           have_regset_tdb = (s390_get_hwcap (tdesc) & HWCAP_S390_TE) != 0;
 474
 475         if (have_regset_tdb)
 476           tdesc = tdesc_s390_te_linux64;
 477         else if (have_regset_system_call)
 478           tdesc = tdesc_s390_linux64v2;
 479         else if (have_regset_last_break)
 480           tdesc = tdesc_s390_linux64v1;
 481         else
 482           tdesc = tdesc_s390_linux64;
 483       }
 484   }
 485 #endif
 486
 487   /* Update target_regsets according to available register sets.  */
 488   for (regset = s390_regsets; regset->fill_function != NULL; regset++)
 489     if (regset->get_request == PTRACE_GETREGSET)
 490       switch (regset->nt_type)
 491         {
 492         case NT_S390_LAST_BREAK:
 493           regset->size = have_regset_last_break? 8 : 0;
 494           break;
 495         case NT_S390_SYSTEM_CALL:
 496           regset->size = have_regset_system_call? 4 : 0;
 497           break;
 498         case NT_S390_TDB:
 499           regset->size = have_regset_tdb ? 256 : 0;
 500         default:
 501           break;
 502         }
 503
 504   current_process ()->tdesc = tdesc;
 505 }
 506
 507
 508 static int
 509 s390_breakpoint_at (CORE_ADDR pc)
 510 {
 511   unsigned char c[s390_breakpoint_len];
 512   read_inferior_memory (pc, c, s390_breakpoint_len);
 513   return memcmp (c, s390_breakpoint, s390_breakpoint_len) == 0;
 514 }
 515
 516 static struct usrregs_info s390_usrregs_info =
 517   {
 518     s390_num_regs,
 519     s390_regmap,
 520   };
 521
 522 static struct regsets_info s390_regsets_info =
 523   {
 524     s390_regsets, /* regsets */
 525     0, /* num_regsets */
 526     NULL, /* disabled_regsets */
 527   };
 528
 529 static struct regs_info regs_info =
 530   {
 531     NULL, /* regset_bitmap */
 532     &s390_usrregs_info,
 533     &s390_regsets_info
 534   };
 535
 536 #ifdef __s390x__
 537 static struct usrregs_info s390_usrregs_info_3264 =
 538   {
 539     s390_num_regs_3264,
 540     s390_regmap_3264
 541   };
 542
 543 static struct regsets_info s390_regsets_info_3264 =
 544   {
 545     s390_regsets, /* regsets */
 546     0, /* num_regsets */
 547     NULL, /* disabled_regsets */
 548   };
 549
 550 static struct regs_info regs_info_3264 =
 551   {
 552     NULL, /* regset_bitmap */
 553     &s390_usrregs_info_3264,
 554     &s390_regsets_info_3264
 555   };
 556 #endif
 557
 558 static const struct regs_info *
 559 s390_regs_info (void)
 560 {
 561 #ifdef __s390x__
 562   if (have_hwcap_s390_high_gprs)
 563     {
 564       const struct target_desc *tdesc = current_process ()->tdesc;
 565
 566       if (register_size (tdesc, 0) == 4)
 567         return &regs_info_3264;
 568     }
 569 #endif
 570   return &regs_info;
 571 }
 572
 573 struct linux_target_ops the_low_target = {
 574   s390_arch_setup,
 575   s390_regs_info,
 576   s390_cannot_fetch_register,
 577   s390_cannot_store_register,
 578   NULL, /* fetch_register */
 579   s390_get_pc,
 580   s390_set_pc,
 581   s390_breakpoint,
 582   s390_breakpoint_len,
 583   NULL,
 584   s390_breakpoint_len,
 585   s390_breakpoint_at,
 586   NULL,  /* supports_z_point_type */
 587   NULL,
 588   NULL,
 589   NULL,
 590   NULL,
 591   s390_collect_ptrace_register,
 592   s390_supply_ptrace_register,
 593 };
 594
 595 void
 596 initialize_low_arch (void)
 597 {
 598   /* Initialize the Linux target descriptions.  */
 599
 600   init_registers_s390_linux32 ();
 601   init_registers_s390_linux32v1 ();
 602   init_registers_s390_linux32v2 ();
 603   init_registers_s390_linux64 ();
 604   init_registers_s390_linux64v1 ();
 605   init_registers_s390_linux64v2 ();
 606   init_registers_s390_te_linux64 ();
 607   init_registers_s390x_linux64 ();
 608   init_registers_s390x_linux64v1 ();
 609   init_registers_s390x_linux64v2 ();
 610   init_registers_s390x_te_linux64 ();
 611
 612   initialize_regsets_info (&s390_regsets_info);
 613 #ifdef __s390x__
 614   initialize_regsets_info (&s390_regsets_info_3264);
 615 #endif
 616 }