summaryrefslogtreecommitdiffstats
path: root/arch/um/os-Linux/tt.c
blob: 5461a065bbb924104dbb395538a6675cbfd9f4e1 (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
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
/*
 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
 * Licensed under the GPL
 */

#include <stdio.h>
#include <unistd.h>
#include <signal.h>
#include <sched.h>
#include <errno.h>
#include <stdarg.h>
#include <stdlib.h>
#include <setjmp.h>
#include <sys/time.h>
#include <sys/ptrace.h>
#include <linux/ptrace.h>
#include <sys/wait.h>
#include <sys/mman.h>
#include <asm/ptrace.h>
#include <asm/unistd.h>
#include <asm/page.h>
#include "user_util.h"
#include "kern_util.h"
#include "user.h"
#include "signal_kern.h"
#include "sysdep/ptrace.h"
#include "sysdep/sigcontext.h"
#include "irq_user.h"
#include "ptrace_user.h"
#include "init.h"
#include "os.h"
#include "uml-config.h"
#include "choose-mode.h"
#include "mode.h"
#include "tempfile.h"

int protect_memory(unsigned long addr, unsigned long len, int r, int w, int x,
		   int must_succeed)
{
	int err;

	err = os_protect_memory((void *) addr, len, r, w, x);
	if(err < 0){
                if(must_succeed)
			panic("protect failed, err = %d", -err);
		else return(err);
	}
	return(0);
}

void kill_child_dead(int pid)
{
	kill(pid, SIGKILL);
	kill(pid, SIGCONT);
	do {
		int n;
		CATCH_EINTR(n = waitpid(pid, NULL, 0));
		if (n > 0)
			kill(pid, SIGCONT);
		else
			break;
	} while(1);
}

void stop(void)
{
	while(1) sleep(1000000);
}

int wait_for_stop(int pid, int sig, int cont_type, void *relay)
{
	sigset_t *relay_signals = relay;
	int status, ret;

	while(1){
		CATCH_EINTR(ret = waitpid(pid, &status, WUNTRACED));
		if((ret < 0) ||
		   !WIFSTOPPED(status) || (WSTOPSIG(status) != sig)){
			if(ret < 0){
				printk("wait failed, errno = %d\n",
				       errno);
			}
			else if(WIFEXITED(status))
				printk("process %d exited with status %d\n",
				       pid, WEXITSTATUS(status));
			else if(WIFSIGNALED(status))
				printk("process %d exited with signal %d\n",
				       pid, WTERMSIG(status));
			else if((WSTOPSIG(status) == SIGVTALRM) ||
				(WSTOPSIG(status) == SIGALRM) ||
				(WSTOPSIG(status) == SIGIO) ||
				(WSTOPSIG(status) == SIGPROF) ||
				(WSTOPSIG(status) == SIGCHLD) ||
				(WSTOPSIG(status) == SIGWINCH) ||
				(WSTOPSIG(status) == SIGINT)){
				ptrace(cont_type, pid, 0, WSTOPSIG(status));
				continue;
			}
			else if((relay_signals != NULL) &&
				sigismember(relay_signals, WSTOPSIG(status))){
				ptrace(cont_type, pid, 0, WSTOPSIG(status));
				continue;
			}
			else printk("process %d stopped with signal %d\n",
				    pid, WSTOPSIG(status));
			panic("wait_for_stop failed to wait for %d to stop "
			      "with %d\n", pid, sig);
		}
		return(status);
	}
}

void forward_ipi(int fd, int pid)
{
	int err;

	err = os_set_owner(fd, pid);
	if(err < 0)
		printk("forward_ipi: set_owner failed, fd = %d, me = %d, "
		       "target = %d, err = %d\n", fd, os_getpid(), pid, -err);
}

/*
 *-------------------------
 * only for tt mode (will be deleted in future...)
 *-------------------------
 */

struct tramp {
	int (*tramp)(void *);
	void *tramp_data;
	unsigned long temp_stack;
	int flags;
	int pid;
};

/* See above for why sigkill is here */

int sigkill = SIGKILL;

int outer_tramp(void *arg)
{
	struct tramp *t;
	int sig = sigkill;

	t = arg;
	t->pid = clone(t->tramp, (void *) t->temp_stack + page_size()/2,
		       t->flags, t->tramp_data);
	if(t->pid > 0) wait_for_stop(t->pid, SIGSTOP, PTRACE_CONT, NULL);
	kill(os_getpid(), sig);
	_exit(0);
}

int start_fork_tramp(void *thread_arg, unsigned long temp_stack,
		     int clone_flags, int (*tramp)(void *))
{
	struct tramp arg;
	unsigned long sp;
	int new_pid, status, err;

	/* The trampoline will run on the temporary stack */
	sp = stack_sp(temp_stack);

	clone_flags |= CLONE_FILES | SIGCHLD;

	arg.tramp = tramp;
	arg.tramp_data = thread_arg;
	arg.temp_stack = temp_stack;
	arg.flags = clone_flags;

	/* Start the process and wait for it to kill itself */
	new_pid = clone(outer_tramp, (void *) sp, clone_flags, &arg);
	if(new_pid < 0)
		return(new_pid);

	CATCH_EINTR(err = waitpid(new_pid, &status, 0));
	if(err < 0)
		panic("Waiting for outer trampoline failed - errno = %d",
		      errno);

	if(!WIFSIGNALED(status) || (WTERMSIG(status) != SIGKILL))
		panic("outer trampoline didn't exit with SIGKILL, "
		      "status = %d", status);

	return(arg.pid);
}

void forward_pending_sigio(int target)
{
	sigset_t sigs;

	if(sigpending(&sigs))
		panic("forward_pending_sigio : sigpending failed");
	if(sigismember(&sigs, SIGIO))
		kill(target, SIGIO);
}

OpenPOWER on IntegriCloud