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
|
/* Special definitions for ix86 machine using segment register based
thread descriptor.
Copyright (C) 1998, 2000, 2001, 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#ifndef __ASSEMBLER__
#include <stddef.h> /* For offsetof. */
#include <stdlib.h> /* For abort(). */
/* We don't want to include the kernel header. So duplicate the
information. */
/* Structure passed on `modify_ldt' call. */
struct modify_ldt_ldt_s
{
unsigned int entry_number;
unsigned long int base_addr;
unsigned int limit;
unsigned int seg_32bit:1;
unsigned int contents:2;
unsigned int read_exec_only:1;
unsigned int limit_in_pages:1;
unsigned int seg_not_present:1;
unsigned int useable:1;
unsigned int empty:25;
};
/* System call to set LDT entry. */
extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t);
/* Return the thread descriptor for the current thread.
The contained asm must *not* be marked volatile since otherwise
assignments like
pthread_descr self = thread_self();
do not get optimized away. */
#define THREAD_SELF \
({ \
register pthread_descr __self; \
__asm__ ("movl %%gs:%c1,%0" : "=r" (__self) \
: "i" (offsetof (struct _pthread_descr_struct, \
p_header.data.self))); \
__self; \
})
/* Initialize the thread-unique value. Two possible ways to do it. */
#define DO_MODIFY_LDT(descr, nr) \
({ \
struct modify_ldt_ldt_s ldt_entry = \
{ nr, (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \
1, 0, 0, 1, 0, 1, 0 }; \
if (__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) \
abort (); \
asm ("movw %w0, %%gs" : : "q" (nr * 8 + 7)); \
})
#ifdef __PIC__
# define USETLS_EBX_ARG "r"
# define USETLS_LOAD_EBX "xchgl %1, %%ebx\n\t"
#else
# define USETLS_EBX_ARG "b"
# define USETLS_LOAD_EBX
#endif
/* When using the new set_thread_area call, we don't need to change %gs
because we inherited the value set up in the main thread by TLS setup.
We need to extract that value and set up the same segment in this
thread. */
#if USE_TLS
# define DO_SET_THREAD_AREA_REUSE(nr) 1
#else
/* Without TLS, we do the initialization of the main thread, where NR == 0. */
# define DO_SET_THREAD_AREA_REUSE(nr) (!__builtin_constant_p (nr) || (nr))
#endif
#define DO_SET_THREAD_AREA(descr, nr) \
({ \
int __gs; \
if (DO_SET_THREAD_AREA_REUSE (nr)) \
{ \
asm ("movw %%gs, %w0" : "=q" (__gs)); \
struct modify_ldt_ldt_s ldt_entry = \
{ (__gs & 0xffff) >> 3, \
(unsigned long int) (descr), 0xfffff /* 4GB in pages */, \
1, 0, 0, 1, 0, 1, 0 }; \
\
int __result; \
__asm (USETLS_LOAD_EBX \
"movl %2, %%eax\n\t" \
"int $0x80\n\t" \
USETLS_LOAD_EBX \
: "=&a" (__result) \
: USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area)); \
if (__result == 0) \
asm ("movw %w0, %%gs" :: "q" (__gs)); \
else \
__gs = -1; \
} \
else \
{ \
struct modify_ldt_ldt_s ldt_entry = \
{ -1, \
(unsigned long int) (descr), 0xfffff /* 4GB in pages */, \
1, 0, 0, 1, 0, 1, 0 }; \
int __result; \
__asm (USETLS_LOAD_EBX \
"movl %2, %%eax\n\t" \
"int $0x80\n\t" \
USETLS_LOAD_EBX \
: "=&a" (__result) \
: USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area)); \
if (__result == 0) \
{ \
__gs = (ldt_entry.entry_number << 3) + 3; \
asm ("movw %w0, %%gs" : : "q" (__gs)); \
} \
else \
__gs = -1; \
} \
__gs; \
})
#if defined __ASSUME_SET_THREAD_AREA_SYSCALL
# define INIT_THREAD_SELF(descr, nr) DO_SET_THREAD_AREA (descr, nr)
#elif defined __NR_set_thread_area
# define INIT_THREAD_SELF(descr, nr) \
({ \
if (__builtin_expect (__have_no_set_thread_area, 0) \
|| (DO_SET_THREAD_AREA (descr, DO_SET_THREAD_AREA_REUSE (nr)) == -1 \
&& (__have_no_set_thread_area = 1))) \
DO_MODIFY_LDT (descr, nr); \
})
/* Defined in pspinlock.c. */
extern int __have_no_set_thread_area;
#else
# define INIT_THREAD_SELF(descr, nr) DO_MODIFY_LDT (descr, nr)
#endif
/* Free resources associated with thread descriptor. */
#ifdef __ASSUME_SET_THREAD_AREA_SYSCALL
#define FREE_THREAD(descr, nr) do { } while (0)
#elif defined __NR_set_thread_area
#define FREE_THREAD(descr, nr) \
{ \
int __gs; \
__asm__ __volatile__ ("movw %%gs, %w0" : "=q" (__gs)); \
if (__builtin_expect (__gs & 4, 0)) \
{ \
struct modify_ldt_ldt_s ldt_entry = \
{ nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 }; \
__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)); \
} \
}
#else
#define FREE_THREAD(descr, nr) \
{ \
struct modify_ldt_ldt_s ldt_entry = \
{ nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 }; \
__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)); \
}
#endif
/* Read member of the thread descriptor directly. */
#define THREAD_GETMEM(descr, member) \
({ \
__typeof__ (descr->member) __value; \
if (sizeof (__value) == 1) \
__asm__ __volatile__ ("movb %%gs:%P2,%b0" \
: "=q" (__value) \
: "0" (0), \
"i" (offsetof (struct _pthread_descr_struct, \
member))); \
else if (sizeof (__value) == 4) \
__asm__ __volatile__ ("movl %%gs:%P1,%0" \
: "=r" (__value) \
: "i" (offsetof (struct _pthread_descr_struct, \
member))); \
else \
{ \
if (sizeof (__value) != 8) \
/* There should not be any value with a size other than 1, 4 or 8. */\
abort (); \
\
__asm__ __volatile__ ("movl %%gs:%P1,%%eax\n\t" \
"movl %%gs:%P2,%%edx" \
: "=A" (__value) \
: "i" (offsetof (struct _pthread_descr_struct, \
member)), \
"i" (offsetof (struct _pthread_descr_struct, \
member) + 4)); \
} \
__value; \
})
/* Same as THREAD_GETMEM, but the member offset can be non-constant. */
#define THREAD_GETMEM_NC(descr, member) \
({ \
__typeof__ (descr->member) __value; \
if (sizeof (__value) == 1) \
__asm__ __volatile__ ("movb %%gs:(%2),%b0" \
: "=q" (__value) \
: "0" (0), \
"r" (offsetof (struct _pthread_descr_struct, \
member))); \
else if (sizeof (__value) == 4) \
__asm__ __volatile__ ("movl %%gs:(%1),%0" \
: "=r" (__value) \
: "r" (offsetof (struct _pthread_descr_struct, \
member))); \
else \
{ \
if (sizeof (__value) != 8) \
/* There should not be any value with a size other than 1, 4 or 8. */\
abort (); \
\
__asm__ __volatile__ ("movl %%gs:(%1),%%eax\n\t" \
"movl %%gs:4(%1),%%edx" \
: "=&A" (__value) \
: "r" (offsetof (struct _pthread_descr_struct, \
member))); \
} \
__value; \
})
/* Same as THREAD_SETMEM, but the member offset can be non-constant. */
#define THREAD_SETMEM(descr, member, value) \
({ \
__typeof__ (descr->member) __value = (value); \
if (sizeof (__value) == 1) \
__asm__ __volatile__ ("movb %0,%%gs:%P1" : \
: "q" (__value), \
"i" (offsetof (struct _pthread_descr_struct, \
member))); \
else if (sizeof (__value) == 4) \
__asm__ __volatile__ ("movl %0,%%gs:%P1" : \
: "r" (__value), \
"i" (offsetof (struct _pthread_descr_struct, \
member))); \
else \
{ \
if (sizeof (__value) != 8) \
/* There should not be any value with a size other than 1, 4 or 8. */\
abort (); \
\
__asm__ __volatile__ ("movl %%eax,%%gs:%P1\n\n" \
"movl %%edx,%%gs:%P2" : \
: "A" (__value), \
"i" (offsetof (struct _pthread_descr_struct, \
member)), \
"i" (offsetof (struct _pthread_descr_struct, \
member) + 4)); \
} \
})
/* Set member of the thread descriptor directly. */
#define THREAD_SETMEM_NC(descr, member, value) \
({ \
__typeof__ (descr->member) __value = (value); \
if (sizeof (__value) == 1) \
__asm__ __volatile__ ("movb %0,%%gs:(%1)" : \
: "q" (__value), \
"r" (offsetof (struct _pthread_descr_struct, \
member))); \
else if (sizeof (__value) == 4) \
__asm__ __volatile__ ("movl %0,%%gs:(%1)" : \
: "r" (__value), \
"r" (offsetof (struct _pthread_descr_struct, \
member))); \
else \
{ \
if (sizeof (__value) != 8) \
/* There should not be any value with a size other than 1, 4 or 8. */\
abort (); \
\
__asm__ __volatile__ ("movl %%eax,%%gs:(%1)\n\t" \
"movl %%edx,%%gs:4(%1)" : \
: "A" (__value), \
"r" (offsetof (struct _pthread_descr_struct, \
member))); \
} \
})
#endif
#if __ASSUME_LDT_WORKS > 0
/* We want the OS to assign stack addresses. */
#define FLOATING_STACKS 1
/* Maximum size of the stack if the rlimit is unlimited. */
#define ARCH_STACK_MAX_SIZE 8*1024*1024
#endif
|
