LXR linux/arch/um/kernel/skas/process.c

   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
  13int 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
  32extern void start_kernel(void);
  33
  34static 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        init_cpu_online(get_cpu_mask(0));
  45#endif
  46        start_kernel();
  47        return 0;
  48}
  49
  50extern int userspace_pid[];
  51
  52extern char cpu0_irqstack[];
  53
  54int __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
  75unsigned long current_stub_stack(void)
  76{
  77        if (current->mm == NULL)
  78                return 0;
  79
  80        return current->mm->context.id.stack;
  81}
  82