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
|
/*
* Copyright (C) 2004 PathScale, Inc
* Licensed under the GPL
*/
#include <signal.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <stdarg.h>
#include <string.h>
#include <sys/mman.h>
#include "user_util.h"
#include "user.h"
#include "signal_kern.h"
#include "sysdep/sigcontext.h"
#include "sysdep/signal.h"
#include "sigcontext.h"
#include "mode.h"
#include "os.h"
void sig_handler(ARCH_SIGHDLR_PARAM)
{
struct sigcontext *sc;
ARCH_GET_SIGCONTEXT(sc, sig);
CHOOSE_MODE_PROC(sig_handler_common_tt, sig_handler_common_skas,
sig, sc);
}
extern int timer_irq_inited;
void alarm_handler(ARCH_SIGHDLR_PARAM)
{
struct sigcontext *sc;
ARCH_GET_SIGCONTEXT(sc, sig);
if(!timer_irq_inited) return;
if(sig == SIGALRM)
switch_timers(0);
CHOOSE_MODE_PROC(sig_handler_common_tt, sig_handler_common_skas,
sig, sc);
if(sig == SIGALRM)
switch_timers(1);
}
extern void do_boot_timer_handler(struct sigcontext * sc);
void boot_timer_handler(ARCH_SIGHDLR_PARAM)
{
struct sigcontext *sc;
ARCH_GET_SIGCONTEXT(sc, sig);
do_boot_timer_handler(sc);
}
void set_sigstack(void *sig_stack, int size)
{
stack_t stack = ((stack_t) { .ss_flags = 0,
.ss_sp = (__ptr_t) sig_stack,
.ss_size = size - sizeof(void *) });
if(sigaltstack(&stack, NULL) != 0)
panic("enabling signal stack failed, errno = %d\n", errno);
}
void remove_sigstack(void)
{
stack_t stack = ((stack_t) { .ss_flags = SS_DISABLE,
.ss_sp = NULL,
.ss_size = 0 });
if(sigaltstack(&stack, NULL) != 0)
panic("disabling signal stack failed, errno = %d\n", errno);
}
void set_handler(int sig, void (*handler)(int), int flags, ...)
{
struct sigaction action;
va_list ap;
int mask;
va_start(ap, flags);
action.sa_handler = handler;
sigemptyset(&action.sa_mask);
while((mask = va_arg(ap, int)) != -1){
sigaddset(&action.sa_mask, mask);
}
va_end(ap);
action.sa_flags = flags;
action.sa_restorer = NULL;
if(sigaction(sig, &action, NULL) < 0)
panic("sigaction failed");
}
int change_sig(int signal, int on)
{
sigset_t sigset, old;
sigemptyset(&sigset);
sigaddset(&sigset, signal);
sigprocmask(on ? SIG_UNBLOCK : SIG_BLOCK, &sigset, &old);
return(!sigismember(&old, signal));
}
/* Both here and in set/get_signal we don't touch SIGPROF, because we must not
* disable profiling; it's safe because the profiling code does not interact
* with the kernel code at all.*/
static void change_signals(int type)
{
sigset_t mask;
sigemptyset(&mask);
sigaddset(&mask, SIGVTALRM);
sigaddset(&mask, SIGALRM);
sigaddset(&mask, SIGIO);
if(sigprocmask(type, &mask, NULL) < 0)
panic("Failed to change signal mask - errno = %d", errno);
}
void block_signals(void)
{
change_signals(SIG_BLOCK);
}
void unblock_signals(void)
{
change_signals(SIG_UNBLOCK);
}
/* These are the asynchronous signals. SIGVTALRM and SIGARLM are handled
* together under SIGVTALRM_BIT. SIGPROF is excluded because we want to
* be able to profile all of UML, not just the non-critical sections. If
* profiling is not thread-safe, then that is not my problem. We can disable
* profiling when SMP is enabled in that case.
*/
#define SIGIO_BIT 0
#define SIGVTALRM_BIT 1
static int enable_mask(sigset_t *mask)
{
int sigs;
sigs = sigismember(mask, SIGIO) ? 0 : 1 << SIGIO_BIT;
sigs |= sigismember(mask, SIGVTALRM) ? 0 : 1 << SIGVTALRM_BIT;
sigs |= sigismember(mask, SIGALRM) ? 0 : 1 << SIGVTALRM_BIT;
return(sigs);
}
int get_signals(void)
{
sigset_t mask;
if(sigprocmask(SIG_SETMASK, NULL, &mask) < 0)
panic("Failed to get signal mask");
return(enable_mask(&mask));
}
int set_signals(int enable)
{
sigset_t mask;
int ret;
sigemptyset(&mask);
if(enable & (1 << SIGIO_BIT))
sigaddset(&mask, SIGIO);
if(enable & (1 << SIGVTALRM_BIT)){
sigaddset(&mask, SIGVTALRM);
sigaddset(&mask, SIGALRM);
}
/* This is safe - sigprocmask is guaranteed to copy locally the
* value of new_set, do his work and then, at the end, write to
* old_set.
*/
if(sigprocmask(SIG_UNBLOCK, &mask, &mask) < 0)
panic("Failed to enable signals");
ret = enable_mask(&mask);
sigemptyset(&mask);
if((enable & (1 << SIGIO_BIT)) == 0)
sigaddset(&mask, SIGIO);
if((enable & (1 << SIGVTALRM_BIT)) == 0){
sigaddset(&mask, SIGVTALRM);
sigaddset(&mask, SIGALRM);
}
if(sigprocmask(SIG_BLOCK, &mask, NULL) < 0)
panic("Failed to block signals");
return(ret);
}
void os_usr1_signal(int on)
{
change_sig(SIGUSR1, on);
}
|
