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
|
/* Copyright (C) 2011-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
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. If not, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include <asm/errno.h>
#include <arch/spr_def.h>
#include <arch/abi.h>
#include "ucontext_i.h"
/* PL to return to via iret in setcontext */
#define RETURN_PL 0
/* int setcontext (const ucontext_t *ucp) */
.text
ENTRY (__setcontext)
FEEDBACK_ENTER(__setcontext)
/* See if this is a true signal context (flags == 0).
If so, restore by invoking rt_sigreturn(). */
#if UC_FLAGS_OFFSET != 0
# error "Add offset to r0 prior to load."
#endif
LD_PTR r10, r0
{
BEQZ r10, .Lsigreturn
addi r10, r10, -1 /* Confirm that it has value "1". */
}
BNEZ r10, .Lbadcontext
/* Save lr and r0 briefly on the stack and set the signal mask:
rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG / 8). */
{
ST sp, lr
ADDI_PTR r11, sp, -(2 * REGSIZE)
move r10, sp
}
ADDI_PTR sp, sp, -(3 * REGSIZE)
cfi_def_cfa_offset (3 * REGSIZE)
cfi_offset (lr, 0)
{
ST r11, r10
ADDI_PTR r10, sp, (2 * REGSIZE)
}
{
ST r10, r0
ADDLI_PTR r1, r0, UC_SIGMASK_OFFSET
}
cfi_offset (r0, -REGSIZE)
{
movei r3, _NSIG / 8
movei r2, 0
}
{
movei r0, SIG_SETMASK
moveli TREG_SYSCALL_NR_NAME, __NR_rt_sigprocmask
}
swint1
ADDI_PTR r11, sp, 2 * REGSIZE /* Restore uc_context to r11. */
{
LD r11, r11
ADDI_PTR sp, sp, 3 * REGSIZE
}
cfi_def_cfa_offset (0)
LD lr, sp
{
ADDI_PTR r10, r11, UC_REG(0)
BNEZ r1, .Lsyscall_error
}
/* Restore the argument registers; note they will be random
unless makecontext() has been called. */
{ LD r0, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r1, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r2, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r3, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r4, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r5, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r6, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r7, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r8, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r9, r10; ADDLI_PTR r10, r10, UC_REG(30) - UC_REG(9) }
/* Restore the callee-saved GPRs. */
{ LD r30, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r31, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r32, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r33, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r34, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r35, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r36, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r37, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r38, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r39, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r40, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r41, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r42, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r43, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r44, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r45, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r46, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r47, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r48, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r49, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r50, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r51, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r52, r10; ADDI_PTR r10, r10, REGSIZE * 2 }
/* Skip tp since it must not change for a given thread. */
{ LD sp, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD lr, r10; ADDI_PTR r10, r10, REGSIZE }
{ LD r11, r10; ADDI_PTR r10, r10, REGSIZE }
/* Construct an iret context; we set ICS so we can validly load
EX_CONTEXT for iret without being interrupted halfway through. */
{
LD r12, r10
movei r13, 1
}
{
mtspr INTERRUPT_CRITICAL_SECTION, r13
shli r12, r12, SPR_EX_CONTEXT_0_1__ICS_SHIFT
}
{
mtspr EX_CONTEXT_0_0, r11
ori r12, r12, RETURN_PL
}
mtspr EX_CONTEXT_0_1, r12
iret
jrp lr /* keep the backtracer happy */
.Lsigreturn:
/* This is a context obtained from a signal handler.
Perform a full restore by pushing the context
passed onto a simulated signal frame on the stack
and call the signal return syscall as if a signal
handler exited normally. */
{
ADDLI_PTR sp, sp, -(C_ABI_SAVE_AREA_SIZE + SI_MAX_SIZE + UC_SIZE)
ADDLI_PTR r1, sp, -UC_SIZE
}
cfi_def_cfa_offset (C_ABI_SAVE_AREA_SIZE + SI_MAX_SIZE + UC_SIZE)
moveli r2, UC_SIZE / REGSIZE
0: {
LD r10, r0
ADDI_PTR r0, r0, REGSIZE
}
{
ST r1, r10
ADDI_PTR r1, r1, REGSIZE
addi r2, r2, -1
}
BNEZ r2, 0b
moveli TREG_SYSCALL_NR_NAME, __NR_rt_sigreturn
swint1
/* Restore the stack and fall through to the error
path. Successful rt_sigreturn never returns to
its calling place. */
ADDLI_PTR sp, sp, (C_ABI_SAVE_AREA_SIZE + SI_MAX_SIZE + UC_SIZE)
cfi_def_cfa_offset (0)
.Lsyscall_error:
j SYSCALL_ERROR_NAME
.Lbadcontext:
{
movei r1, EINVAL
j SYSCALL_ERROR_NAME
}
END (__setcontext)
.hidden __setcontext
weak_alias (__setcontext, setcontext)
ENTRY (__startcontext)
FEEDBACK_ENTER(__startcontext)
BEQZ r30, 1f
{
move r0, r30
jal __setcontext
}
1: {
movei r0, 0
j HIDDEN_JUMPTARGET(exit)
}
END (__startcontext)
.hidden __startcontext
|
GitWeb