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
|
/* Intel 386 native support for System V systems (pre-SVR4).
Copyright (C) 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,
2000, 2002, 2007 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 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., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */
#include "defs.h"
#ifdef HAVE_PTRACE_H
#include <ptrace.h>
#else
#ifdef HAVE_SYS_PTRACE_H
#include <sys/ptrace.h>
#endif
#endif
#include "frame.h"
#include "inferior.h"
#include "language.h"
#include "gdbcore.h"
#include <sys/param.h>
#include <sys/dir.h>
#include <signal.h>
#include <sys/user.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#ifdef TARGET_HAS_HARDWARE_WATCHPOINTS
#include <sys/debugreg.h>
#endif
#include <sys/file.h>
#include "gdb_stat.h"
#ifdef HAVE_SYS_REG_H
#include <sys/reg.h>
#endif
#include "floatformat.h"
#include "target.h"
#include "i386-tdep.h"
/* Mapping between the general-purpose registers in `struct user'
format and GDB's register array layout. */
static int regmap[] =
{
EAX, ECX, EDX, EBX,
UESP, EBP, ESI, EDI,
EIP, EFL, CS, SS,
DS, ES, FS, GS,
};
/* Support for the user struct. */
/* Return the address of register REGNUM. BLOCKEND is the value of
u.u_ar0, and points to the place where GS is stored. */
CORE_ADDR
register_u_addr (CORE_ADDR blockend, int regnum)
{
struct user u;
CORE_ADDR fpstate;
if (i386_fp_regnum_p (regnum))
{
#ifdef KSTKSZ /* SCO, and others? */
blockend += 4 * (SS + 1) - KSTKSZ;
fpstate = blockend + ((char *) &u.u_fps.u_fpstate - (char *) &u);
return (fpstate + 0x1c + 10 * (regnum - FP0_REGNUM));
#else
fpstate = blockend + ((char *) &u.i387.st_space - (char *) &u);
return (fpstate + 10 * (regnum - FP0_REGNUM));
#endif
}
return (blockend + 4 * regmap[regnum]);
}
/* Return the size of the user struct. */
int
kernel_u_size (void)
{
return (sizeof (struct user));
}
#ifdef TARGET_HAS_HARDWARE_WATCHPOINTS
#if !defined (offsetof)
#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
#endif
/* Record the value of the debug control register. */
static int debug_control_mirror;
/* Record which address associates with which register. */
static CORE_ADDR address_lookup[DR_LASTADDR - DR_FIRSTADDR + 1];
static int i386_insert_aligned_watchpoint (int, CORE_ADDR, CORE_ADDR, int,
int);
static int i386_insert_nonaligned_watchpoint (int, CORE_ADDR, CORE_ADDR, int,
int);
/* Insert a watchpoint. */
int
i386_insert_watchpoint (int pid, CORE_ADDR addr, int len, int rw)
{
return i386_insert_aligned_watchpoint (pid, addr, addr, len, rw);
}
static int
i386_insert_aligned_watchpoint (int pid, CORE_ADDR waddr, CORE_ADDR addr,
int len, int rw)
{
int i;
int read_write_bits, len_bits;
int free_debug_register;
int register_number;
/* Look for a free debug register. */
for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
{
if (address_lookup[i - DR_FIRSTADDR] == 0)
break;
}
/* No more debug registers! */
if (i > DR_LASTADDR)
return -1;
read_write_bits = (rw & 1) ? DR_RW_READ : DR_RW_WRITE;
if (len == 1)
len_bits = DR_LEN_1;
else if (len == 2)
{
if (addr % 2)
return i386_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw);
len_bits = DR_LEN_2;
}
else if (len == 4)
{
if (addr % 4)
return i386_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw);
len_bits = DR_LEN_4;
}
else
return i386_insert_nonaligned_watchpoint (pid, waddr, addr, len, rw);
free_debug_register = i;
register_number = free_debug_register - DR_FIRSTADDR;
debug_control_mirror |=
((read_write_bits | len_bits)
<< (DR_CONTROL_SHIFT + DR_CONTROL_SIZE * register_number));
debug_control_mirror |=
(1 << (DR_LOCAL_ENABLE_SHIFT + DR_ENABLE_SIZE * register_number));
debug_control_mirror |= DR_LOCAL_SLOWDOWN;
debug_control_mirror &= ~DR_CONTROL_RESERVED;
ptrace (6, pid, offsetof (struct user, u_debugreg[DR_CONTROL]),
debug_control_mirror);
ptrace (6, pid, offsetof (struct user, u_debugreg[free_debug_register]),
addr);
/* Record where we came from. */
address_lookup[register_number] = addr;
return 0;
}
static int
i386_insert_nonaligned_watchpoint (int pid, CORE_ADDR waddr, CORE_ADDR addr,
int len, int rw)
{
int align;
int size;
int rv;
static int size_try_array[4][4] =
{
{ 1, 1, 1, 1 }, /* trying size one */
{ 2, 1, 2, 1 }, /* trying size two */
{ 2, 1, 2, 1 }, /* trying size three */
{ 4, 1, 2, 1 } /* trying size four */
};
rv = 0;
while (len > 0)
{
align = addr % 4;
/* Four is the maximum length for 386. */
size = size_try_array[len > 4 ? 3 : len - 1][align];
rv = i386_insert_aligned_watchpoint (pid, waddr, addr, size, rw);
if (rv)
{
i386_remove_watchpoint (pid, waddr, size);
return rv;
}
addr += size;
len -= size;
}
return rv;
}
/* Remove a watchpoint. */
int
i386_remove_watchpoint (int pid, CORE_ADDR addr, int len)
{
int i;
int register_number;
for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
{
register_number = i - DR_FIRSTADDR;
if (address_lookup[register_number] == addr)
{
debug_control_mirror &=
~(1 << (DR_LOCAL_ENABLE_SHIFT + DR_ENABLE_SIZE * register_number));
address_lookup[register_number] = 0;
}
}
ptrace (6, pid, offsetof (struct user, u_debugreg[DR_CONTROL]),
debug_control_mirror);
ptrace (6, pid, offsetof (struct user, u_debugreg[DR_STATUS]), 0);
return 0;
}
/* Check if stopped by a watchpoint. */
CORE_ADDR
i386_stopped_by_watchpoint (int pid)
{
int i;
int status;
status = ptrace (3, pid, offsetof (struct user, u_debugreg[DR_STATUS]), 0);
ptrace (6, pid, offsetof (struct user, u_debugreg[DR_STATUS]), 0);
for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
{
if (status & (1 << (i - DR_FIRSTADDR)))
return address_lookup[i - DR_FIRSTADDR];
}
return 0;
}
#endif /* TARGET_HAS_HARDWARE_WATCHPOINTS */
|
