arch/um/kernel/skas/process.c

/*
 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
 * Licensed under the GPL
 */

#include "linux/sched.h"
#include "linux/slab.h"
#include "linux/ptrace.h"
#include "linux/proc_fs.h"
#include "linux/file.h"
#include "linux/errno.h"
#include "linux/init.h"
#include "asm/uaccess.h"
#include "asm/atomic.h"
#include "kern_util.h"
#include "as-layout.h"
#include "skas.h"
#include "os.h"
#include "tlb.h"
#include "kern.h"
#include "registers.h"

extern void schedule_tail(struct task_struct *prev);

int new_mm(unsigned long stack)
{
	int fd;

	fd = os_open_file("/proc/mm", of_cloexec(of_write(OPENFLAGS())), 0);
	if(fd < 0)
		return fd;

	if(skas_needs_stub)
		map_stub_pages(fd, CONFIG_STUB_CODE, CONFIG_STUB_DATA, stack);

	return fd;
}

extern void start_kernel(void);

static int __init start_kernel_proc(void *unused)
{
	int pid;

	block_signals();
	pid = os_getpid();

	cpu_tasks[0].pid = pid;
	cpu_tasks[0].task = current;
#ifdef CONFIG_SMP
	cpu_online_map = cpumask_of_cpu(0);
#endif
	start_kernel();
	return 0;
}

extern int userspace_pid[];

extern char cpu0_irqstack[];

int __init start_uml(void)
{
	stack_protections((unsigned long) &cpu0_irqstack);
	set_sigstack(cpu0_irqstack, THREAD_SIZE);
	if(proc_mm)
		userspace_pid[0] = start_userspace(0);

	init_new_thread_signals();

	init_task.thread.request.u.thread.proc = start_kernel_proc;
	init_task.thread.request.u.thread.arg = NULL;
	return start_idle_thread(task_stack_page(&init_task),
				 &init_task.thread.switch_buf);
}

unsigned long current_stub_stack(void)
{
	if(current->mm == NULL)
		return 0;

	return current->mm->context.skas.id.stack;
}