/home/lenb/linux-2.6 branch 'acpi-2.6.12'
[linux-2.6] / arch / um / kernel / skas / clone.c
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
13 /* This is in a separate file because it needs to be compiled with any
14  * extraneous gcc flags (-pg, -fprofile-arcs, -ftest-coverage) disabled
15  */
16 void __attribute__ ((__section__ (".__syscall_stub")))
17 stub_clone_handler(void)
18 {
19         long err;
20         struct stub_data *from = (struct stub_data *) UML_CONFIG_STUB_DATA;
21
22         err = stub_syscall2(__NR_clone, CLONE_PARENT | CLONE_FILES | SIGCHLD,
23                             UML_CONFIG_STUB_DATA + PAGE_SIZE / 2 -
24                             sizeof(void *));
25         if(err != 0)
26                 goto out;
27
28         err = stub_syscall4(__NR_ptrace, PTRACE_TRACEME, 0, 0, 0);
29         if(err)
30                 goto out;
31
32         err = stub_syscall3(__NR_setitimer, ITIMER_VIRTUAL,
33                             (long) &from->timer, 0);
34         if(err)
35                 goto out;
36
37         err = stub_syscall6(STUB_MMAP_NR, UML_CONFIG_STUB_DATA, PAGE_SIZE,
38                             PROT_READ | PROT_WRITE, MAP_FIXED | MAP_SHARED,
39                             from->fd, from->offset);
40  out:
41         /* save current result. Parent: pid; child: retcode of mmap */
42         from->err = err;
43         trap_myself();
44 }