gdb/gdbserver/linux-x86-64-low.c

   1 /* GNU/Linux/x86-64 specific low level interface, for the remote server
   2    for GDB.
   3    Copyright (C) 2002, 2004, 2005, 2006, 2007, 2008, 2009
   4    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 "server.h"
  22 #include "linux-low.h"
  23 #include "i387-fp.h"
  24
  25 #include "gdb_proc_service.h"
  26
  27 /* Defined in auto-generated file reg-x86-64-linux.c.  */
  28 void init_registers_x86_64_linux (void);
  29
  30 #include <sys/reg.h>
  31 #include <sys/procfs.h>
  32 #include <sys/ptrace.h>
  33
  34 /* This definition comes from prctl.h, but some kernels may not have it.  */
  35 #ifndef PTRACE_ARCH_PRCTL
  36 #define PTRACE_ARCH_PRCTL      30
  37 #endif
  38
  39 /* The following definitions come from prctl.h, but may be absent
  40    for certain configurations.  */
  41 #ifndef ARCH_GET_FS
  42 #define ARCH_SET_GS 0x1001
  43 #define ARCH_SET_FS 0x1002
  44 #define ARCH_GET_FS 0x1003
  45 #define ARCH_GET_GS 0x1004
  46 #endif
  47
  48 static int x86_64_regmap[] = {
  49   RAX * 8, RBX * 8, RCX * 8, RDX * 8,
  50   RSI * 8, RDI * 8, RBP * 8, RSP * 8,
  51   R8 * 8, R9 * 8, R10 * 8, R11 * 8,
  52   R12 * 8, R13 * 8, R14 * 8, R15 * 8,
  53   RIP * 8, EFLAGS * 8, CS * 8, SS * 8,
  54   DS * 8, ES * 8, FS * 8, GS * 8,
  55   -1, -1, -1, -1, -1, -1, -1, -1,
  56   -1, -1, -1, -1, -1, -1, -1, -1,
  57   -1, -1, -1, -1, -1, -1, -1, -1,
  58   -1, -1, -1, -1, -1, -1, -1, -1, -1,
  59   ORIG_RAX * 8
  60 };
  61
  62 #define X86_64_NUM_GREGS (sizeof(x86_64_regmap)/sizeof(int))
  63
  64 /* Called by libthread_db.  */
  65
  66 ps_err_e
  67 ps_get_thread_area (const struct ps_prochandle *ph,
  68                     lwpid_t lwpid, int idx, void **base)
  69 {
  70   switch (idx)
  71     {
  72     case FS:
  73       if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_FS) == 0)
  74         return PS_OK;
  75       break;
  76     case GS:
  77       if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_GS) == 0)
  78         return PS_OK;
  79       break;
  80     default:
  81       return PS_BADADDR;
  82     }
  83   return PS_ERR;
  84 }
  85
  86 static void
  87 x86_64_fill_gregset (void *buf)
  88 {
  89   int i;
  90
  91   for (i = 0; i < X86_64_NUM_GREGS; i++)
  92     if (x86_64_regmap[i] != -1)
  93       collect_register (i, ((char *) buf) + x86_64_regmap[i]);
  94 }
  95
  96 static void
  97 x86_64_store_gregset (const void *buf)
  98 {
  99   int i;
 100
 101   for (i = 0; i < X86_64_NUM_GREGS; i++)
 102     if (x86_64_regmap[i] != -1)
 103       supply_register (i, ((char *) buf) + x86_64_regmap[i]);
 104 }
 105
 106 static void
 107 x86_64_fill_fpregset (void *buf)
 108 {
 109   i387_cache_to_fxsave (buf);
 110 }
 111
 112 static void
 113 x86_64_store_fpregset (const void *buf)
 114 {
 115   i387_fxsave_to_cache (buf);
 116 }
 117
 118 struct regset_info target_regsets[] = {
 119   { PTRACE_GETREGS, PTRACE_SETREGS, sizeof (elf_gregset_t),
 120     GENERAL_REGS,
 121     x86_64_fill_gregset, x86_64_store_gregset },
 122   { PTRACE_GETFPREGS, PTRACE_SETFPREGS, sizeof (elf_fpregset_t),
 123     FP_REGS,
 124     x86_64_fill_fpregset, x86_64_store_fpregset },
 125   { 0, 0, -1, -1, NULL, NULL }
 126 };
 127
 128 static const unsigned char x86_64_breakpoint[] = { 0xCC };
 129 #define x86_64_breakpoint_len 1
 130
 131 extern int debug_threads;
 132
 133 static CORE_ADDR
 134 x86_64_get_pc ()
 135 {
 136   unsigned long pc;
 137
 138   collect_register_by_name ("rip", &pc);
 139
 140   if (debug_threads)
 141     fprintf (stderr, "stop pc (before any decrement) is %08lx\n", pc);
 142   return pc;
 143 }
 144
 145 static void
 146 x86_64_set_pc (CORE_ADDR newpc)
 147 {
 148   if (debug_threads)
 149     fprintf (stderr, "set pc to %08lx\n", (long) newpc);
 150   supply_register_by_name ("rip", &newpc);
 151 }
 152
 153 static int
 154 x86_64_breakpoint_at (CORE_ADDR pc)
 155 {
 156   unsigned char c;
 157
 158   read_inferior_memory (pc, &c, 1);
 159   if (c == 0xCC)
 160     return 1;
 161
 162   return 0;
 163 }
 164
 165 struct linux_target_ops the_low_target = {
 166   init_registers_x86_64_linux,
 167   -1,
 168   NULL,
 169   NULL,
 170   NULL,
 171   x86_64_get_pc,
 172   x86_64_set_pc,
 173   x86_64_breakpoint,
 174   x86_64_breakpoint_len,
 175   NULL,
 176   1,
 177   x86_64_breakpoint_at,
 178   NULL,
 179   NULL,
 180   NULL,
 181   NULL,
 182   NULL,
 183   NULL,
 184 };