Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
4 */
5
6#include <stdio.h>
7#include <unistd.h>
8#include <signal.h>
9#include <sched.h>
10#include <errno.h>
11#include <stdarg.h>
12#include <stdlib.h>
13#include <setjmp.h>
14#include <sys/time.h>
15#include <sys/ptrace.h>
16#include <linux/ptrace.h>
17#include <sys/wait.h>
18#include <sys/mman.h>
19#include <asm/ptrace.h>
20#include <asm/unistd.h>
21#include <asm/page.h>
22#include "user_util.h"
23#include "kern_util.h"
24#include "user.h"
25#include "signal_kern.h"
26#include "signal_user.h"
27#include "sysdep/ptrace.h"
28#include "sysdep/sigcontext.h"
29#include "irq_user.h"
30#include "ptrace_user.h"
31#include "time_user.h"
32#include "init.h"
33#include "os.h"
34#include "uml-config.h"
35#include "choose-mode.h"
36#include "mode.h"
37#include "tempfile.h"
38
39int protect_memory(unsigned long addr, unsigned long len, int r, int w, int x,
40 int must_succeed)
41{
42 int err;
43
44 err = os_protect_memory((void *) addr, len, r, w, x);
45 if(err < 0){
46 if(must_succeed)
47 panic("protect failed, err = %d", -err);
48 else return(err);
49 }
50 return(0);
51}
52
53/*
54 *-------------------------
55 * only for tt mode (will be deleted in future...)
56 *-------------------------
57 */
58
59struct tramp {
60 int (*tramp)(void *);
61 void *tramp_data;
62 unsigned long temp_stack;
63 int flags;
64 int pid;
65};
66
67/* See above for why sigkill is here */
68
69int sigkill = SIGKILL;
70
71int outer_tramp(void *arg)
72{
73 struct tramp *t;
74 int sig = sigkill;
75
76 t = arg;
77 t->pid = clone(t->tramp, (void *) t->temp_stack + page_size()/2,
78 t->flags, t->tramp_data);
79 if(t->pid > 0) wait_for_stop(t->pid, SIGSTOP, PTRACE_CONT, NULL);
80 kill(os_getpid(), sig);
81 _exit(0);
82}
83
84int start_fork_tramp(void *thread_arg, unsigned long temp_stack,
85 int clone_flags, int (*tramp)(void *))
86{
87 struct tramp arg;
88 unsigned long sp;
89 int new_pid, status, err;
90
91 /* The trampoline will run on the temporary stack */
92 sp = stack_sp(temp_stack);
93
94 clone_flags |= CLONE_FILES | SIGCHLD;
95
96 arg.tramp = tramp;
97 arg.tramp_data = thread_arg;
98 arg.temp_stack = temp_stack;
99 arg.flags = clone_flags;
100
101 /* Start the process and wait for it to kill itself */
102 new_pid = clone(outer_tramp, (void *) sp, clone_flags, &arg);
103 if(new_pid < 0)
104 return(new_pid);
105
106 CATCH_EINTR(err = waitpid(new_pid, &status, 0));
107 if(err < 0)
108 panic("Waiting for outer trampoline failed - errno = %d",
109 errno);
110
111 if(!WIFSIGNALED(status) || (WTERMSIG(status) != SIGKILL))
112 panic("outer trampoline didn't exit with SIGKILL, "
113 "status = %d", status);
114
115 return(arg.pid);
116}
117
118void forward_pending_sigio(int target)
119{
120 sigset_t sigs;
121
122 if(sigpending(&sigs))
123 panic("forward_pending_sigio : sigpending failed");
124 if(sigismember(&sigs, SIGIO))
125 kill(target, SIGIO);
126}
127