aboutsummaryrefslogtreecommitdiff
path: root/gdb/x86-bsd-nat.c
blob: dff2a004a548c0581187709bb3f8d04c4741f9ca (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
/* Native-dependent code for X86 BSD's.

   Copyright (C) 2003-2018 Free Software Foundation, Inc.

   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 3 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, see <http://www.gnu.org/licenses/>.  */

#include "defs.h"
#include "inferior.h"
#include "gdbthread.h"

/* We include <signal.h> to make sure `struct fxsave64' is defined on
   NetBSD, since NetBSD's <machine/reg.h> needs it.  */
#include <signal.h>
#include <sys/types.h>
#include <sys/ptrace.h>
#include <machine/reg.h>

#include "x86-nat.h"
#include "x86-bsd-nat.h"
#include "inf-ptrace.h"


#ifdef PT_GETXSTATE_INFO
size_t x86bsd_xsave_len;
#endif

/* Support for debug registers.  */

#ifdef HAVE_PT_GETDBREGS
static void (*super_mourn_inferior) (struct target_ops *ops);

/* Implement the "to_mourn_inferior" target_ops method.  */

static void
x86bsd_mourn_inferior (struct target_ops *ops)
{
  x86_cleanup_dregs ();
  super_mourn_inferior (ops);
}

/* Helper macro to access debug register X.  FreeBSD/amd64 and modern
   versions of FreeBSD/i386 provide this macro in system headers.  Define
   a local version for systems that do not provide it.  */
#ifndef DBREG_DRX
#ifdef __NetBSD__
#define DBREG_DRX(d, x) ((d)->dr[x])
#else
#define DBREG_DRX(d, x) ((&d->dr0)[x])
#endif
#endif

static unsigned long
x86bsd_dr_get (ptid_t ptid, int regnum)
{
  struct dbreg dbregs;

  if (ptrace (PT_GETDBREGS, get_ptrace_pid (inferior_ptid),
	      (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
    perror_with_name (_("Couldn't read debug registers"));

  return DBREG_DRX ((&dbregs), regnum);
}

static void
x86bsd_dr_set (int regnum, unsigned long value)
{
  struct thread_info *thread;
  struct dbreg dbregs;

  if (ptrace (PT_GETDBREGS, get_ptrace_pid (inferior_ptid),
              (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
    perror_with_name (_("Couldn't get debug registers"));

  /* For some mysterious reason, some of the reserved bits in the
     debug control register get set.  Mask these off, otherwise the
     ptrace call below will fail.  */
  DBREG_DRX ((&dbregs), 7) &= ~(0xffffffff0000fc00);

  DBREG_DRX ((&dbregs), regnum) = value;

  ALL_NON_EXITED_THREADS (thread)
    if (thread->inf == current_inferior ())
      {
	if (ptrace (PT_SETDBREGS, get_ptrace_pid (thread->ptid),
		    (PTRACE_TYPE_ARG3) &dbregs, 0) == -1)
	  perror_with_name (_("Couldn't write debug registers"));
      }
}

static void
x86bsd_dr_set_control (unsigned long control)
{
  x86bsd_dr_set (7, control);
}

static void
x86bsd_dr_set_addr (int regnum, CORE_ADDR addr)
{
  gdb_assert (regnum >= 0 && regnum <= 4);

  x86bsd_dr_set (regnum, addr);
}

static CORE_ADDR
x86bsd_dr_get_addr (int regnum)
{
  return x86bsd_dr_get (inferior_ptid, regnum);
}

static unsigned long
x86bsd_dr_get_status (void)
{
  return x86bsd_dr_get (inferior_ptid, 6);
}

static unsigned long
x86bsd_dr_get_control (void)
{
  return x86bsd_dr_get (inferior_ptid, 7);
}

#endif /* PT_GETDBREGS */

/* Create a prototype *BSD/x86 target.  The client can override it
   with local methods.  */

struct target_ops *
x86bsd_target (void)
{
  struct target_ops *t;

  t = inf_ptrace_target ();

#ifdef HAVE_PT_GETDBREGS
  x86_use_watchpoints (t);

  x86_dr_low.set_control = x86bsd_dr_set_control;
  x86_dr_low.set_addr = x86bsd_dr_set_addr;
  x86_dr_low.get_addr = x86bsd_dr_get_addr;
  x86_dr_low.get_status = x86bsd_dr_get_status;
  x86_dr_low.get_control = x86bsd_dr_get_control;
  x86_set_debug_register_length (sizeof (void *));
  super_mourn_inferior = t->to_mourn_inferior;
  t->to_mourn_inferior = x86bsd_mourn_inferior;
#endif /* HAVE_PT_GETDBREGS */

  return t;
}