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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 "time_user.h"
#include "signal_user.h"
#include "skas.h"
#include "os.h"
#include "user_util.h"
#include "tlb.h"
#include "kern.h"
#include "mode.h"
#include "proc_mm.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);
to->thread.prev_sched = from;
set_current(to);
switch_threads(&from->thread.mode.skas.switch_buf,
to->thread.mode.skas.switch_buf);
if(current->pid == 0)
switch_timers(1);
return(current->thread.prev_sched);
}
extern void schedule_tail(struct task_struct *prev);
void new_thread_handler(int sig)
{
int (*fn)(void *), n;
void *arg;
fn = current->thread.request.u.thread.proc;
arg = current->thread.request.u.thread.arg;
change_sig(SIGUSR1, 1);
thread_wait(¤t->thread.mode.skas.switch_buf,
current->thread.mode.skas.fork_buf);
if(current->thread.prev_sched != NULL)
schedule_tail(current->thread.prev_sched);
current->thread.prev_sched = NULL;
/* 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)
userspace(¤t->thread.regs.regs);
else do_exit(0);
}
void new_thread_proc(void *stack, void (*handler)(int sig))
{
init_new_thread_stack(stack, handler);
os_usr1_process(os_getpid());
}
void release_thread_skas(struct task_struct *task)
{
}
void exit_thread_skas(void)
{
}
void fork_handler(int sig)
{
change_sig(SIGUSR1, 1);
thread_wait(¤t->thread.mode.skas.switch_buf,
current->thread.mode.skas.fork_buf);
force_flush_all();
if(current->thread.prev_sched == NULL)
panic("blech");
schedule_tail(current->thread.prev_sched);
current->thread.prev_sched = NULL;
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)(int);
if(current->thread.forking){
memcpy(&p->thread.regs.regs.skas,
¤t->thread.regs.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;
}
else {
init_thread_registers(&p->thread.regs.regs);
p->thread.request.u.thread = current->thread.request.u.thread;
handler = new_thread_handler;
}
new_thread(p->thread_info, &p->thread.mode.skas.switch_buf,
&p->thread.mode.skas.fork_buf, handler);
return(0);
}
int new_mm(int from)
{
struct proc_mm_op copy;
int n, fd;
fd = os_open_file("/proc/mm", of_cloexec(of_write(OPENFLAGS())), 0);
if(fd < 0)
return(fd);
if(from != -1){
copy = ((struct proc_mm_op) { .op = MM_COPY_SEGMENTS,
.u =
{ .copy_segments = from } } );
n = os_write_file(fd, ©, sizeof(copy));
if(n != sizeof(copy))
printk("new_mm : /proc/mm copy_segments failed, "
"err = %d\n", -n);
}
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);
}
int start_uml_skas(void)
{
start_userspace(0);
init_new_thread_signals(1);
uml_idle_timer();
init_task.thread.request.u.thread.proc = start_kernel_proc;
init_task.thread.request.u.thread.arg = NULL;
return(start_idle_thread(init_task.thread_info,
&init_task.thread.mode.skas.switch_buf,
&init_task.thread.mode.skas.fork_buf));
}
int external_pid_skas(struct task_struct *task)
{
#warning Need to look up userspace_pid by cpu
return(userspace_pid[0]);
}
int thread_pid_skas(struct task_struct *task)
{
#warning Need to look up userspace_pid by cpu
return(userspace_pid[0]);
}
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/
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