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/*
* 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 "mode.h"
#include "registers.h"
void switch_to_skas(void *prev, void *next)
{
struct task_struct *from, *to;
from = prev;
to = next;
/* XXX need to check runqueues[cpu].idle */
if(current->pid == 0)
switch_timers(0);
switch_threads(&from->thread.mode.skas.switch_buf,
&to->thread.mode.skas.switch_buf);
arch_switch_to_skas(current->thread.prev_sched, current);
if(current->pid == 0)
switch_timers(1);
}
extern void schedule_tail(struct task_struct *prev);
/* This is called magically, by its address being stuffed in a jmp_buf
* and being longjmp-d to.
*/
void new_thread_handler(void)
{
int (*fn)(void *), n;
void *arg;
if(current->thread.prev_sched != NULL)
schedule_tail(current->thread.prev_sched);
current->thread.prev_sched = NULL;
fn = current->thread.request.u.thread.proc;
arg = current->thread.request.u.thread.arg;
/* The return value is 1 if the kernel thread execs a process,
* 0 if it just exits
*/
n = run_kernel_thread(fn, arg, ¤t->thread.exec_buf);
if(n == 1){
/* Handle any immediate reschedules or signals */
interrupt_end();
userspace(¤t->thread.regs.regs);
}
else do_exit(0);
}
void release_thread_skas(struct task_struct *task)
{
}
/* Called magically, see new_thread_handler above */
void fork_handler(void)
{
force_flush_all();
if(current->thread.prev_sched == NULL)
panic("blech");
schedule_tail(current->thread.prev_sched);
/* XXX: if interrupt_end() calls schedule, this call to
* arch_switch_to_skas isn't needed. We could want to apply this to
* improve performance. -bb */
arch_switch_to_skas(current->thread.prev_sched, current);
current->thread.prev_sched = NULL;
/* Handle any immediate reschedules or signals */
interrupt_end();
userspace(¤t->thread.regs.regs);
}
int copy_thread_skas(int nr, unsigned long clone_flags, unsigned long sp,
unsigned long stack_top, struct task_struct * p,
struct pt_regs *regs)
{
void (*handler)(void);
if(current->thread.forking){
memcpy(&p->thread.regs.regs.skas, ®s->regs.skas,
sizeof(p->thread.regs.regs.skas));
REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.skas.regs, 0);
if(sp != 0) REGS_SP(p->thread.regs.regs.skas.regs) = sp;
handler = fork_handler;
arch_copy_thread(¤t->thread.arch, &p->thread.arch);
}
else {
init_thread_registers(&p->thread.regs.regs);
p->thread.request.u.thread = current->thread.request.u.thread;
handler = new_thread_handler;
}
new_thread(task_stack_page(p), &p->thread.mode.skas.switch_buf,
handler);
return(0);
}
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);
}
void init_idle_skas(void)
{
cpu_tasks[current_thread->cpu].pid = os_getpid();
default_idle();
}
extern void start_kernel(void);
static int 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 start_uml_skas(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.mode.skas.switch_buf));
}
int external_pid_skas(struct task_struct *task)
{
/* FIXME: Need to look up userspace_pid by cpu */
return(userspace_pid[0]);
}
int thread_pid_skas(struct task_struct *task)
{
/* FIXME: Need to look up userspace_pid by cpu */
return(userspace_pid[0]);
}
void kill_off_processes_skas(void)
{
if(proc_mm)
/*
* FIXME: need to loop over userspace_pids in
* kill_off_processes_skas
*/
os_kill_ptraced_process(userspace_pid[0], 1);
else {
struct task_struct *p;
int pid, me;
me = os_getpid();
for_each_process(p){
if(p->mm == NULL)
continue;
pid = p->mm->context.skas.id.u.pid;
os_kill_ptraced_process(pid, 1);
}
}
}
unsigned long current_stub_stack(void)
{
if(current->mm == NULL)
return(0);
return(current->mm->context.skas.id.stack);
}
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