1#include <sched.h>
2#include <signal.h>
3#include <sys/mman.h>
4#include <sys/time.h>
5#include <asm/unistd.h>
6#include <asm/page.h>
7#include "ptrace_user.h"
8#include "skas.h"
9#include "stub-data.h"
10#include "uml-config.h"
11#include "sysdep/stub.h"
12#include "kern_constants.h"
13
14/* This is in a separate file because it needs to be compiled with any
15 * extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled
16 *
17 * Use UM_KERN_PAGE_SIZE instead of PAGE_SIZE because that calls getpagesize
18 * on some systems.
19 */
20
21void __attribute__ ((__section__ (".__syscall_stub")))
22stub_clone_handler(void)
23{
24	struct stub_data *data = (struct stub_data *) UML_CONFIG_STUB_DATA;
25	long err;
26
27	err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
28			    UML_CONFIG_STUB_DATA + UM_KERN_PAGE_SIZE / 2 -
29			    sizeof(void *));
30	if(err != 0)
31		goto out;
32
33	err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0);
34	if(err)
35		goto out;
36
37	err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL,
38			    (long) &data->timer, 0);
39	if(err)
40		goto out;
41
42	remap_stack(data->fd, data->offset);
43	goto done;
44
45 out:
46	/* save current result.
47	 * Parent: pid;
48	 * child: retcode of mmap already saved and it jumps around this
49	 * assignment
50	 */
51	data->err = err;
52 done:
53	trap_myself();
54}
55