1 files changed, 137 insertions, 89 deletions

diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index bfa52f206bb..0eae00b3e58 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -1,53 +1,30 @@
 /*
- * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
  * Copyright 2003 PathScale, Inc.
  * Licensed under the GPL
  */
 
-#include "linux/kernel.h"
-#include "linux/sched.h"
-#include "linux/interrupt.h"
-#include "linux/string.h"
+#include "linux/stddef.h"
+#include "linux/err.h"
+#include "linux/hardirq.h"
 #include "linux/mm.h"
-#include "linux/slab.h"
-#include "linux/utsname.h"
-#include "linux/fs.h"
-#include "linux/utime.h"
-#include "linux/smp_lock.h"
-#include "linux/module.h"
-#include "linux/init.h"
-#include "linux/capability.h"
-#include "linux/vmalloc.h"
-#include "linux/spinlock.h"
+#include "linux/personality.h"
 #include "linux/proc_fs.h"
 #include "linux/ptrace.h"
 #include "linux/random.h"
-#include "linux/personality.h"
-#include "asm/unistd.h"
-#include "asm/mman.h"
-#include "asm/segment.h"
-#include "asm/stat.h"
+#include "linux/sched.h"
+#include "linux/tick.h"
+#include "linux/threads.h"
 #include "asm/pgtable.h"
-#include "asm/processor.h"
-#include "asm/tlbflush.h"
 #include "asm/uaccess.h"
-#include "asm/user.h"
-#include "kern_util.h"
 #include "as-layout.h"
-#include "kern.h"
-#include "signal_kern.h"
-#include "init.h"
-#include "irq_user.h"
-#include "mem_user.h"
-#include "tlb.h"
-#include "frame_kern.h"
-#include "sigcontext.h"
+#include "kern_util.h"
 #include "os.h"
-#include "mode.h"
-#include "mode_kern.h"
-#include "choose-mode.h"
+#include "skas.h"
+#include "tlb.h"
 
-/* This is a per-cpu array.  A processor only modifies its entry and it only
+/*
+ * This is a per-cpu array.  A processor only modifies its entry and it only
  * cares about its entry, so it's OK if another processor is modifying its
  * entry.
  */
@@ -55,15 +32,16 @@ struct cpu_task cpu_tasks[NR_CPUS] = { [0 ... NR_CPUS - 1] = { -1, NULL } };
 
 static inline int external_pid(struct task_struct *task)
 {
-	return CHOOSE_MODE_PROC(external_pid_tt, external_pid_skas, task);
+	/* FIXME: Need to look up userspace_pid by cpu */
+	return userspace_pid[0];
 }
 
 int pid_to_processor_id(int pid)
 {
 	int i;
 
-	for(i = 0; i < ncpus; i++){
-		if(cpu_tasks[i].pid == pid)
+	for(i = 0; i < ncpus; i++) {
+		if (cpu_tasks[i].pid == pid)
 			return i;
 	}
 	return -1;
@@ -82,9 +60,9 @@ unsigned long alloc_stack(int order, int atomic)
 	if (atomic)
 		flags = GFP_ATOMIC;
 	page = __get_free_pages(flags, order);
-	if(page == 0)
+	if (page == 0)
 		return 0;
-	stack_protections(page);
+
 	return page;
 }
 
@@ -105,6 +83,8 @@ static inline void set_current(struct task_struct *task)
 		{ external_pid(task), task });
 }
 
+extern void arch_switch_to(struct task_struct *from, struct task_struct *to);
+
 void *_switch_to(void *prev, void *next, void *last)
 {
 	struct task_struct *from = prev;
@@ -114,9 +94,14 @@ void *_switch_to(void *prev, void *next, void *last)
 	set_current(to);
 
 	do {
-		current->thread.saved_task = NULL ;
-		CHOOSE_MODE_PROC(switch_to_tt, switch_to_skas, prev, next);
-		if(current->thread.saved_task)
+		current->thread.saved_task = NULL;
+
+		switch_threads(&from->thread.switch_buf,
+			       &to->thread.switch_buf);
+
+		arch_switch_to(current->thread.prev_sched, current);
+
+		if (current->thread.saved_task)
 			show_regs(&(current->thread.regs));
 		next= current->thread.saved_task;
 		prev= current;
@@ -128,20 +113,14 @@ void *_switch_to(void *prev, void *next, void *last)
 
 void interrupt_end(void)
 {
-	if(need_resched())
+	if (need_resched())
 		schedule();
-	if(test_tsk_thread_flag(current, TIF_SIGPENDING))
+	if (test_tsk_thread_flag(current, TIF_SIGPENDING))
 		do_signal();
 }
 
-void release_thread(struct task_struct *task)
-{
-	CHOOSE_MODE(release_thread_tt(task), release_thread_skas(task));
-}
-
 void exit_thread(void)
 {
-	unprotect_stack((unsigned long) current_thread);
 }
 
 void *get_current(void)
@@ -149,28 +128,99 @@ void *get_current(void)
 	return current;
 }
 
+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, &current->thread.exec_buf);
+	if (n == 1) {
+		/* Handle any immediate reschedules or signals */
+		interrupt_end();
+		userspace(&current->thread.regs.regs);
+	}
+	else do_exit(0);
+}
+
+/* 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 isn't needed. We could want to apply this to
+	 * improve performance. -bb
+	 */
+	arch_switch_to(current->thread.prev_sched, current);
+
+	current->thread.prev_sched = NULL;
+
+	/* Handle any immediate reschedules or signals */
+	interrupt_end();
+
+	userspace(&current->thread.regs.regs);
+}
+
 int copy_thread(int nr, unsigned long clone_flags, unsigned long sp,
 		unsigned long stack_top, struct task_struct * p,
 		struct pt_regs *regs)
 {
-	int ret;
+	void (*handler)(void);
+	int ret = 0;
 
 	p->thread = (struct thread_struct) INIT_THREAD;
-	ret = CHOOSE_MODE_PROC(copy_thread_tt, copy_thread_skas, nr,
-				clone_flags, sp, stack_top, p, regs);
 
-	if (ret || !current->thread.forking)
-		goto out;
+	if (current->thread.forking) {
+	  	memcpy(&p->thread.regs.regs, &regs->regs,
+		       sizeof(p->thread.regs.regs));
+		REGS_SET_SYSCALL_RETURN(p->thread.regs.regs.gp, 0);
+		if (sp != 0)
+			REGS_SP(p->thread.regs.regs.gp) = sp;
 
-	clear_flushed_tls(p);
+		handler = fork_handler;
 
-	/*
-	 * Set a new TLS for the child thread?
-	 */
-	if (clone_flags & CLONE_SETTLS)
-		ret = arch_copy_tls(p);
+		arch_copy_thread(&current->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.switch_buf, handler);
+
+	if (current->thread.forking) {
+		clear_flushed_tls(p);
+
+		/*
+		 * Set a new TLS for the child thread?
+		 */
+		if (clone_flags & CLONE_SETTLS)
+			ret = arch_copy_tls(p);
+	}
 
-out:
 	return ret;
 }
 
@@ -179,39 +229,35 @@ void initial_thread_cb(void (*proc)(void *), void *arg)
 	int save_kmalloc_ok = kmalloc_ok;
 
 	kmalloc_ok = 0;
-	CHOOSE_MODE_PROC(initial_thread_cb_tt, initial_thread_cb_skas, proc,
-			 arg);
+	initial_thread_cb_skas(proc, arg);
 	kmalloc_ok = save_kmalloc_ok;
 }
 
-#ifdef CONFIG_MODE_TT
-unsigned long stack_sp(unsigned long page)
-{
-	return page + PAGE_SIZE - sizeof(void *);
-}
-#endif
-
 void default_idle(void)
 {
-	CHOOSE_MODE(uml_idle_timer(), (void) 0);
+	unsigned long long nsecs;
 
-	while(1){
+	while(1) {
 		/* endless idle loop with no priority at all */
 
 		/*
 		 * although we are an idle CPU, we do not want to
 		 * get into the scheduler unnecessarily.
 		 */
-		if(need_resched())
+		if (need_resched())
 			schedule();
 
-		idle_sleep(10);
+		tick_nohz_stop_sched_tick();
+		nsecs = disable_timer();
+		idle_sleep(nsecs);
+		tick_nohz_restart_sched_tick();
 	}
 }
 
 void cpu_idle(void)
 {
-	CHOOSE_MODE(init_idle_tt(), init_idle_skas());
+	cpu_tasks[current_thread->cpu].pid = os_getpid();
+	default_idle();
 }
 
 void *um_virt_to_phys(struct task_struct *task, unsigned long addr,
@@ -223,26 +269,26 @@ void *um_virt_to_phys(struct task_struct *task, unsigned long addr,
 	pte_t *pte;
 	pte_t ptent;
 
-	if(task->mm == NULL)
+	if (task->mm == NULL)
 		return ERR_PTR(-EINVAL);
 	pgd = pgd_offset(task->mm, addr);
-	if(!pgd_present(*pgd))
+	if (!pgd_present(*pgd))
 		return ERR_PTR(-EINVAL);
 
 	pud = pud_offset(pgd, addr);
-	if(!pud_present(*pud))
+	if (!pud_present(*pud))
 		return ERR_PTR(-EINVAL);
 
 	pmd = pmd_offset(pud, addr);
-	if(!pmd_present(*pmd))
+	if (!pmd_present(*pmd))
 		return ERR_PTR(-EINVAL);
 
 	pte = pte_offset_kernel(pmd, addr);
 	ptent = *pte;
-	if(!pte_present(ptent))
+	if (!pte_present(ptent))
 		return ERR_PTR(-EINVAL);
 
-	if(pte_out != NULL)
+	if (pte_out != NULL)
 		*pte_out = ptent;
 	return (void *) (pte_val(ptent) & PAGE_MASK) + (addr & ~PAGE_MASK);
 }
@@ -315,7 +361,7 @@ int smp_sigio_handler(void)
 #ifdef CONFIG_SMP
 	int cpu = current_thread->cpu;
 	IPI_handler(cpu);
-	if(cpu != 0)
+	if (cpu != 0)
 		return 1;
 #endif
 	return 0;
@@ -343,7 +389,8 @@ int get_using_sysemu(void)
 
 static int proc_read_sysemu(char *buf, char **start, off_t offset, int size,int *eof, void *data)
 {
-	if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size) /*No overflow*/
+	if (snprintf(buf, size, "%d\n", get_using_sysemu()) < size)
+		/* No overflow */
 		*eof = 1;
 
 	return strlen(buf);
@@ -358,7 +405,8 @@ static int proc_write_sysemu(struct file *file,const char __user *buf, unsigned
 
 	if (tmp[0] >= '0' && tmp[0] <= '2')
 		set_using_sysemu(tmp[0] - '0');
-	return count; /*We use the first char, but pretend to write everything*/
+	/* We use the first char, but pretend to write everything */
+	return count;
 }
 
 int __init make_proc_sysemu(void)
@@ -388,10 +436,10 @@ int singlestepping(void * t)
 	struct task_struct *task = t ? t : current;
 
 	if ( ! (task->ptrace & PT_DTRACE) )
-		return(0);
+		return 0;
 
 	if (task->thread.singlestep_syscall)
-		return(1);
+		return 1;
 
 	return 2;
 }