1 /*
2 * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6 #include "linux/init.h"
7 #include "linux/sched.h"
8 #include "as-layout.h"
9 #include "kern.h"
10 #include "os.h"
11 #include "skas.h"
12
new_mm(unsigned long stack)13 int new_mm(unsigned long stack)
14 {
15 int fd, err;
16
17 fd = os_open_file("/proc/mm", of_cloexec(of_write(OPENFLAGS())), 0);
18 if (fd < 0)
19 return fd;
20
21 if (skas_needs_stub) {
22 err = map_stub_pages(fd, STUB_CODE, STUB_DATA, stack);
23 if (err) {
24 os_close_file(fd);
25 return err;
26 }
27 }
28
29 return fd;
30 }
31
32 extern void start_kernel(void);
33
start_kernel_proc(void * unused)34 static int __init start_kernel_proc(void *unused)
35 {
36 int pid;
37
38 block_signals();
39 pid = os_getpid();
40
41 cpu_tasks[0].pid = pid;
42 cpu_tasks[0].task = current;
43 #ifdef CONFIG_SMP
44 cpu_online_map = cpumask_of_cpu(0);
45 #endif
46 start_kernel();
47 return 0;
48 }
49
50 extern int userspace_pid[];
51
52 extern char cpu0_irqstack[];
53
start_uml(void)54 int __init start_uml(void)
55 {
56 stack_protections((unsigned long) &cpu0_irqstack);
57 set_sigstack(cpu0_irqstack, THREAD_SIZE);
58 if (proc_mm) {
59 userspace_pid[0] = start_userspace(0);
60 if (userspace_pid[0] < 0) {
61 printf("start_uml - start_userspace returned %d\n",
62 userspace_pid[0]);
63 exit(1);
64 }
65 }
66
67 init_new_thread_signals();
68
69 init_task.thread.request.u.thread.proc = start_kernel_proc;
70 init_task.thread.request.u.thread.arg = NULL;
71 return start_idle_thread(task_stack_page(&init_task),
72 &init_task.thread.switch_buf);
73 }
74
current_stub_stack(void)75 unsigned long current_stub_stack(void)
76 {
77 if (current->mm == NULL)
78 return 0;
79
80 return current->mm->context.id.stack;
81 }
82