aboutsummaryrefslogtreecommitdiff
path: root/gdb/amd64-linux-nat.c
blob: ab4725e1dd6055d7ac8becb25c86eeb2c5f41760 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
/* Native-dependent code for GNU/Linux x86-64.

   Copyright 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
   Contributed by Jiri Smid, SuSE Labs.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include "defs.h"
#include "inferior.h"
#include "gdbcore.h"
#include "regcache.h"
#include "linux-nat.h"

#include "gdb_assert.h"
#include "gdb_string.h"
#include <sys/ptrace.h>
#include <sys/debugreg.h>
#include <sys/syscall.h>
#include <sys/procfs.h>
#include <asm/prctl.h>
/* FIXME ezannoni-2003-07-09: we need <sys/reg.h> to be included after
   <asm/ptrace.h> because the latter redefines FS and GS for no apparent
   reason, and those definitions don't match the ones that libpthread_db
   uses, which come from <sys/reg.h>.  */
/* ezannoni-2003-07-09: I think this is fixed. The extraneous defs have
   been removed from ptrace.h in the kernel.  However, better safe than
   sorry.  */
#include <asm/ptrace.h>
#include <sys/reg.h>
#include "gdb_proc_service.h"

/* Prototypes for supply_gregset etc.  */
#include "gregset.h"

#include "amd64-tdep.h"
#include "i386-linux-tdep.h"
#include "amd64-nat.h"

/* Mapping between the general-purpose registers in GNU/Linux x86-64
   `struct user' format and GDB's register cache layout.  */

static int amd64_linux_gregset64_reg_offset[] =
{
  RAX * 8, RBX * 8,		/* %rax, %rbx */
  RCX * 8, RDX * 8,		/* %rcx, %rdx */
  RSI * 8, RDI * 8,		/* %rsi, %rdi */
  RBP * 8, RSP * 8,		/* %rbp, %rsp */
  R8 * 8, R9 * 8,		/* %r8 ... */
  R10 * 8, R11 * 8,
  R12 * 8, R13 * 8,
  R14 * 8, R15 * 8,		/* ... %r15 */
  RIP * 8, EFLAGS * 8,		/* %rip, %eflags */
  CS * 8, SS * 8,		/* %cs, %ss */
  DS * 8, ES * 8,		/* %ds, %es */
  FS * 8, GS * 8		/* %fs, %gs */
};


/* Mapping between the general-purpose registers in GNU/Linux x86-64
   `struct user' format and GDB's register cache layout for GNU/Linux
   i386.

   Note that most GNU/Linux x86-64 registers are 64-bit, while the
   GNU/Linux i386 registers are all 32-bit, but since we're
   little-endian we get away with that.  */

/* From <sys/reg.h> on GNU/Linux i386.  */
static int amd64_linux_gregset32_reg_offset[] =
{
  RAX * 8, RCX * 8,		/* %eax, %ecx */
  RDX * 8, RBX * 8,		/* %edx, %ebx */
  RSP * 8, RBP * 8,		/* %esp, %ebp */
  RSI * 8, RDI * 8,		/* %esi, %edi */
  RIP * 8, EFLAGS * 8,		/* %eip, %eflags */
  CS * 8, SS * 8,		/* %cs, %ss */
  DS * 8, ES * 8,		/* %ds, %es */
  FS * 8, GS * 8,		/* %fs, %gs */
  -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1,
  -1, -1, -1, -1, -1, -1, -1, -1, -1,
  ORIG_RAX * 8			/* "orig_eax" */
};


/* Transfering the general-purpose registers between GDB, inferiors
   and core files.  */

/* Fill GDB's register cache with the general-purpose register values
   in *GREGSETP.  */

void
supply_gregset (elf_gregset_t *gregsetp)
{
  amd64_supply_native_gregset (current_regcache, gregsetp, -1);
}

/* Fill register REGNUM (if it is a general-purpose register) in
   *GREGSETP with the value in GDB's register cache.  If REGNUM is -1,
   do this for all registers.  */

void
fill_gregset (elf_gregset_t *gregsetp, int regnum)
{
  amd64_collect_native_gregset (current_regcache, gregsetp, regnum);
}

/* Transfering floating-point registers between GDB, inferiors and cores.  */

/* Fill GDB's register cache with the floating-point and SSE register
   values in *FPREGSETP.  */

void
supply_fpregset (elf_fpregset_t *fpregsetp)
{
  amd64_supply_fxsave (current_regcache, -1, fpregsetp);
}

/* Fill register REGNUM (if it is a floating-point or SSE register) in
   *FPREGSETP with the value in GDB's register cache.  If REGNUM is
   -1, do this for all registers.  */

void
fill_fpregset (elf_fpregset_t *fpregsetp, int regnum)
{
  amd64_collect_fxsave (current_regcache, regnum, fpregsetp);
}


/* Transferring arbitrary registers between GDB and inferior.  */

/* Fetch register REGNUM from the child process.  If REGNUM is -1, do
   this for all registers (including the floating point and SSE
   registers).  */

void
fetch_inferior_registers (int regnum)
{
  int tid;

  /* GNU/Linux LWP ID's are process ID's.  */
  tid = TIDGET (inferior_ptid);
  if (tid == 0)
    tid = PIDGET (inferior_ptid); /* Not a threaded program.  */

  if (regnum == -1 || amd64_native_gregset_supplies_p (regnum))
    {
      elf_gregset_t regs;

      if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
	perror_with_name ("Couldn't get registers");

      amd64_supply_native_gregset (current_regcache, &regs, -1);
      if (regnum != -1)
	return;
    }

  if (regnum == -1 || !amd64_native_gregset_supplies_p (regnum))
    {
      elf_fpregset_t fpregs;

      if (ptrace (PTRACE_GETFPREGS, tid, 0, (long) &fpregs) < 0)
	perror_with_name ("Couldn't get floating point status");

      amd64_supply_fxsave (current_regcache, -1, &fpregs);
    }
}

/* Store register REGNUM back into the child process.  If REGNUM is
   -1, do this for all registers (including the floating-point and SSE
   registers).  */

void
store_inferior_registers (int regnum)
{
  int tid;

  /* GNU/Linux LWP ID's are process ID's.  */
  tid = TIDGET (inferior_ptid);
  if (tid == 0)
    tid = PIDGET (inferior_ptid); /* Not a threaded program.  */

  if (regnum == -1 || amd64_native_gregset_supplies_p (regnum))
    {
      elf_gregset_t regs;

      if (ptrace (PTRACE_GETREGS, tid, 0, (long) &regs) < 0)
	perror_with_name ("Couldn't get registers");

      amd64_collect_native_gregset (current_regcache, &regs, regnum);

      if (ptrace (PTRACE_SETREGS, tid, 0, (long) &regs) < 0)
	perror_with_name ("Couldn't write registers");

      if (regnum != -1)
	return;
    }

  if (regnum == -1 || !amd64_native_gregset_supplies_p (regnum))
    {
      elf_fpregset_t fpregs;

      if (ptrace (PTRACE_GETFPREGS, tid, 0, (long) &fpregs) < 0)
	perror_with_name ("Couldn't get floating point status");

      amd64_collect_fxsave (current_regcache, regnum, &fpregs);

      if (ptrace (PTRACE_SETFPREGS, tid, 0, (long) &fpregs) < 0)
	perror_with_name ("Couldn't write floating point status");

      return;
    }
}


static unsigned long
amd64_linux_dr_get (int regnum)
{
  int tid;
  unsigned long value;

  /* FIXME: kettenis/2001-01-29: It's not clear what we should do with
     multi-threaded processes here.  For now, pretend there is just
     one thread.  */
  tid = PIDGET (inferior_ptid);

  /* FIXME: kettenis/2001-03-27: Calling perror_with_name if the
     ptrace call fails breaks debugging remote targets.  The correct
     way to fix this is to add the hardware breakpoint and watchpoint
     stuff to the target vectore.  For now, just return zero if the
     ptrace call fails.  */
  errno = 0;
  value = ptrace (PT_READ_U, tid,
		  offsetof (struct user, u_debugreg[regnum]), 0);
  if (errno != 0)
#if 0
    perror_with_name ("Couldn't read debug register");
#else
    return 0;
#endif

  return value;
}

static void
amd64_linux_dr_set (int regnum, unsigned long value)
{
  int tid;

  /* FIXME: kettenis/2001-01-29: It's not clear what we should do with
     multi-threaded processes here.  For now, pretend there is just
     one thread.  */
  tid = PIDGET (inferior_ptid);

  errno = 0;
  ptrace (PT_WRITE_U, tid, offsetof (struct user, u_debugreg[regnum]), value);
  if (errno != 0)
    perror_with_name ("Couldn't write debug register");
}

void
amd64_linux_dr_set_control (unsigned long control)
{
  amd64_linux_dr_set (DR_CONTROL, control);
}

void
amd64_linux_dr_set_addr (int regnum, CORE_ADDR addr)
{
  gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);

  amd64_linux_dr_set (DR_FIRSTADDR + regnum, addr);
}

void
amd64_linux_dr_reset_addr (int regnum)
{
  gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);

  amd64_linux_dr_set (DR_FIRSTADDR + regnum, 0L);
}

unsigned long
amd64_linux_dr_get_status (void)
{
  return amd64_linux_dr_get (DR_STATUS);
}


/* This function is called by libthread_db as part of its handling of
   a request for a thread's local storage address.  */

ps_err_e
ps_get_thread_area (const struct ps_prochandle *ph,
                    lwpid_t lwpid, int idx, void **base)
{
  if (gdbarch_ptr_bit (current_gdbarch) == 32)
    {
      /* The full structure is found in <asm-i386/ldt.h>.  The second
	 integer is the LDT's base_address and that is used to locate
	 the thread's local storage.  See i386-linux-nat.c more
	 info.  */
      unsigned int desc[4];

      /* This code assumes that "int" is 32 bits and that
	 GET_THREAD_AREA returns no more than 4 int values.  */
      gdb_assert (sizeof (int) == 4);	
#ifndef PTRACE_GET_THREAD_AREA
#define PTRACE_GET_THREAD_AREA 25
#endif
      if  (ptrace (PTRACE_GET_THREAD_AREA, 
		   lwpid, (void *) (long) idx, (unsigned long) &desc) < 0)
	return PS_ERR;
      
      /* Extend the value to 64 bits.  Here it's assumed that a "long"
	 and a "void *" are the same.  */
      (*base) = (void *) (long) desc[1];
      return PS_OK;
    }
  else
    {
      /* This definition comes from prctl.h, but some kernels may not
         have it.  */
#ifndef PTRACE_ARCH_PRCTL
#define PTRACE_ARCH_PRCTL      30
#endif
      /* FIXME: ezannoni-2003-07-09 see comment above about include
	 file order.  We could be getting bogus values for these two.  */
      gdb_assert (FS < ELF_NGREG);
      gdb_assert (GS < ELF_NGREG);
      switch (idx)
	{
	case FS:
	  if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_FS) == 0)
	    return PS_OK;
	  break;
	case GS:
	  if (ptrace (PTRACE_ARCH_PRCTL, lwpid, base, ARCH_GET_GS) == 0)
	    return PS_OK;
	  break;
	default:                   /* Should not happen.  */
	  return PS_BADADDR;
	}
    }
  return PS_ERR;               /* ptrace failed.  */
}


void
child_post_startup_inferior (ptid_t ptid)
{
  i386_cleanup_dregs ();
  linux_child_post_startup_inferior (ptid);
}


/* Provide a prototype to silence -Wmissing-prototypes.  */
void _initialize_amd64_linux_nat (void);

void
_initialize_amd64_linux_nat (void)
{
  amd64_native_gregset32_reg_offset = amd64_linux_gregset32_reg_offset;
  amd64_native_gregset32_num_regs = I386_LINUX_NUM_REGS;
  amd64_native_gregset64_reg_offset = amd64_linux_gregset64_reg_offset;

  gdb_assert (ARRAY_SIZE (amd64_linux_gregset32_reg_offset)
	      == amd64_native_gregset32_num_regs);
  gdb_assert (ARRAY_SIZE (amd64_linux_gregset64_reg_offset)
	      == amd64_native_gregset64_num_regs);
}