Merge branch 'upstream'
[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 #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
21 void __attribute__ ((__section__ (".__syscall_stub")))
22 stub_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 }