i386: prepare shared kernel/process.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 0 insertions, 951 deletions

diff --git a/arch/i386/kernel/process.c b/arch/i386/kernel/process.c
deleted file mode 100644
index 84664710b784..000000000000
--- a/arch/i386/kernel/process.c
+++ /dev/null
@@ -1,951 +0,0 @@
-/*
- *  linux/arch/i386/kernel/process.c
- *
- *  Copyright (C) 1995  Linus Torvalds
- *
- *  Pentium III FXSR, SSE support
- *	Gareth Hughes <gareth@valinux.com>, May 2000
- */
-
-/*
- * This file handles the architecture-dependent parts of process handling..
- */
-
-#include <stdarg.h>
-
-#include <linux/cpu.h>
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/fs.h>
-#include <linux/kernel.h>
-#include <linux/mm.h>
-#include <linux/elfcore.h>
-#include <linux/smp.h>
-#include <linux/stddef.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-#include <linux/user.h>
-#include <linux/a.out.h>
-#include <linux/interrupt.h>
-#include <linux/utsname.h>
-#include <linux/delay.h>
-#include <linux/reboot.h>
-#include <linux/init.h>
-#include <linux/mc146818rtc.h>
-#include <linux/module.h>
-#include <linux/kallsyms.h>
-#include <linux/ptrace.h>
-#include <linux/random.h>
-#include <linux/personality.h>
-#include <linux/tick.h>
-#include <linux/percpu.h>
-
-#include <asm/uaccess.h>
-#include <asm/pgtable.h>
-#include <asm/system.h>
-#include <asm/io.h>
-#include <asm/ldt.h>
-#include <asm/processor.h>
-#include <asm/i387.h>
-#include <asm/desc.h>
-#include <asm/vm86.h>
-#ifdef CONFIG_MATH_EMULATION
-#include <asm/math_emu.h>
-#endif
-
-#include <linux/err.h>
-
-#include <asm/tlbflush.h>
-#include <asm/cpu.h>
-
-asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
-
-static int hlt_counter;
-
-unsigned long boot_option_idle_override = 0;
-EXPORT_SYMBOL(boot_option_idle_override);
-
-DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task;
-EXPORT_PER_CPU_SYMBOL(current_task);
-
-DEFINE_PER_CPU(int, cpu_number);
-EXPORT_PER_CPU_SYMBOL(cpu_number);
-
-/*
- * Return saved PC of a blocked thread.
- */
-unsigned long thread_saved_pc(struct task_struct *tsk)
-{
-	return ((unsigned long *)tsk->thread.esp)[3];
-}
-
-/*
- * Powermanagement idle function, if any..
- */
-void (*pm_idle)(void);
-EXPORT_SYMBOL(pm_idle);
-static DEFINE_PER_CPU(unsigned int, cpu_idle_state);
-
-void disable_hlt(void)
-{
-	hlt_counter++;
-}
-
-EXPORT_SYMBOL(disable_hlt);
-
-void enable_hlt(void)
-{
-	hlt_counter--;
-}
-
-EXPORT_SYMBOL(enable_hlt);
-
-/*
- * We use this if we don't have any better
- * idle routine..
- */
-void default_idle(void)
-{
-	if (!hlt_counter && boot_cpu_data.hlt_works_ok) {
-		current_thread_info()->status &= ~TS_POLLING;
-		/*
-		 * TS_POLLING-cleared state must be visible before we
-		 * test NEED_RESCHED:
-		 */
-		smp_mb();
-
-		local_irq_disable();
-		if (!need_resched())
-			safe_halt();	/* enables interrupts racelessly */
-		else
-			local_irq_enable();
-		current_thread_info()->status |= TS_POLLING;
-	} else {
-		/* loop is done by the caller */
-		cpu_relax();
-	}
-}
-#ifdef CONFIG_APM_MODULE
-EXPORT_SYMBOL(default_idle);
-#endif
-
-/*
- * On SMP it's slightly faster (but much more power-consuming!)
- * to poll the ->work.need_resched flag instead of waiting for the
- * cross-CPU IPI to arrive. Use this option with caution.
- */
-static void poll_idle (void)
-{
-	cpu_relax();
-}
-
-#ifdef CONFIG_HOTPLUG_CPU
-#include <asm/nmi.h>
-/* We don't actually take CPU down, just spin without interrupts. */
-static inline void play_dead(void)
-{
-	/* This must be done before dead CPU ack */
-	cpu_exit_clear();
-	wbinvd();
-	mb();
-	/* Ack it */
-	__get_cpu_var(cpu_state) = CPU_DEAD;
-
-	/*
-	 * With physical CPU hotplug, we should halt the cpu
-	 */
-	local_irq_disable();
-	while (1)
-		halt();
-}
-#else
-static inline void play_dead(void)
-{
-	BUG();
-}
-#endif /* CONFIG_HOTPLUG_CPU */
-
-/*
- * The idle thread. There's no useful work to be
- * done, so just try to conserve power and have a
- * low exit latency (ie sit in a loop waiting for
- * somebody to say that they'd like to reschedule)
- */
-void cpu_idle(void)
-{
-	int cpu = smp_processor_id();
-
-	current_thread_info()->status |= TS_POLLING;
-
-	/* endless idle loop with no priority at all */
-	while (1) {
-		tick_nohz_stop_sched_tick();
-		while (!need_resched()) {
-			void (*idle)(void);
-
-			if (__get_cpu_var(cpu_idle_state))
-				__get_cpu_var(cpu_idle_state) = 0;
-
-			check_pgt_cache();
-			rmb();
-			idle = pm_idle;
-
-			if (!idle)
-				idle = default_idle;
-
-			if (cpu_is_offline(cpu))
-				play_dead();
-
-			__get_cpu_var(irq_stat).idle_timestamp = jiffies;
-			idle();
-		}
-		tick_nohz_restart_sched_tick();
-		preempt_enable_no_resched();
-		schedule();
-		preempt_disable();
-	}
-}
-
-void cpu_idle_wait(void)
-{
-	unsigned int cpu, this_cpu = get_cpu();
-	cpumask_t map, tmp = current->cpus_allowed;
-
-	set_cpus_allowed(current, cpumask_of_cpu(this_cpu));
-	put_cpu();
-
-	cpus_clear(map);
-	for_each_online_cpu(cpu) {
-		per_cpu(cpu_idle_state, cpu) = 1;
-		cpu_set(cpu, map);
-	}
-
-	__get_cpu_var(cpu_idle_state) = 0;
-
-	wmb();
-	do {
-		ssleep(1);
-		for_each_online_cpu(cpu) {
-			if (cpu_isset(cpu, map) && !per_cpu(cpu_idle_state, cpu))
-				cpu_clear(cpu, map);
-		}
-		cpus_and(map, map, cpu_online_map);
-	} while (!cpus_empty(map));
-
-	set_cpus_allowed(current, tmp);
-}
-EXPORT_SYMBOL_GPL(cpu_idle_wait);
-
-/*
- * This uses new MONITOR/MWAIT instructions on P4 processors with PNI,
- * which can obviate IPI to trigger checking of need_resched.
- * We execute MONITOR against need_resched and enter optimized wait state
- * through MWAIT. Whenever someone changes need_resched, we would be woken
- * up from MWAIT (without an IPI).
- *
- * New with Core Duo processors, MWAIT can take some hints based on CPU
- * capability.
- */
-void mwait_idle_with_hints(unsigned long eax, unsigned long ecx)
-{
-	if (!need_resched()) {
-		__monitor((void *)&current_thread_info()->flags, 0, 0);
-		smp_mb();
-		if (!need_resched())
-			__mwait(eax, ecx);
-	}
-}
-
-/* Default MONITOR/MWAIT with no hints, used for default C1 state */
-static void mwait_idle(void)
-{
-	local_irq_enable();
-	mwait_idle_with_hints(0, 0);
-}
-
-void __devinit select_idle_routine(const struct cpuinfo_x86 *c)
-{
-	if (cpu_has(c, X86_FEATURE_MWAIT)) {
-		printk("monitor/mwait feature present.\n");
-		/*
-		 * Skip, if setup has overridden idle.
-		 * One CPU supports mwait => All CPUs supports mwait
-		 */
-		if (!pm_idle) {
-			printk("using mwait in idle threads.\n");
-			pm_idle = mwait_idle;
-		}
-	}
-}
-
-static int __init idle_setup(char *str)
-{
-	if (!strcmp(str, "poll")) {
-		printk("using polling idle threads.\n");
-		pm_idle = poll_idle;
-#ifdef CONFIG_X86_SMP
-		if (smp_num_siblings > 1)
-			printk("WARNING: polling idle and HT enabled, performance may degrade.\n");
-#endif
-	} else if (!strcmp(str, "mwait"))
-		force_mwait = 1;
-	else
-		return -1;
-
-	boot_option_idle_override = 1;
-	return 0;
-}
-early_param("idle", idle_setup);
-
-void show_regs(struct pt_regs * regs)
-{
-	unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;
-	unsigned long d0, d1, d2, d3, d6, d7;
-
-	printk("\n");
-	printk("Pid: %d, comm: %20s\n", current->pid, current->comm);
-	printk("EIP: %04x:[<%08lx>] CPU: %d\n",0xffff & regs->xcs,regs->eip, smp_processor_id());
-	print_symbol("EIP is at %s\n", regs->eip);
-
-	if (user_mode_vm(regs))
-		printk(" ESP: %04x:%08lx",0xffff & regs->xss,regs->esp);
-	printk(" EFLAGS: %08lx    %s  (%s %.*s)\n",
-	       regs->eflags, print_tainted(), init_utsname()->release,
-	       (int)strcspn(init_utsname()->version, " "),
-	       init_utsname()->version);
-	printk("EAX: %08lx EBX: %08lx ECX: %08lx EDX: %08lx\n",
-		regs->eax,regs->ebx,regs->ecx,regs->edx);
-	printk("ESI: %08lx EDI: %08lx EBP: %08lx",
-		regs->esi, regs->edi, regs->ebp);
-	printk(" DS: %04x ES: %04x FS: %04x\n",
-	       0xffff & regs->xds,0xffff & regs->xes, 0xffff & regs->xfs);
-
-	cr0 = read_cr0();
-	cr2 = read_cr2();
-	cr3 = read_cr3();
-	cr4 = read_cr4_safe();
-	printk("CR0: %08lx CR2: %08lx CR3: %08lx CR4: %08lx\n", cr0, cr2, cr3, cr4);
-
-	get_debugreg(d0, 0);
-	get_debugreg(d1, 1);
-	get_debugreg(d2, 2);
-	get_debugreg(d3, 3);
-	printk("DR0: %08lx DR1: %08lx DR2: %08lx DR3: %08lx\n",
-			d0, d1, d2, d3);
-	get_debugreg(d6, 6);
-	get_debugreg(d7, 7);
-	printk("DR6: %08lx DR7: %08lx\n", d6, d7);
-
-	show_trace(NULL, regs, &regs->esp);
-}
-
-/*
- * This gets run with %ebx containing the
- * function to call, and %edx containing
- * the "args".
- */
-extern void kernel_thread_helper(void);
-
-/*
- * Create a kernel thread
- */
-int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
-{
-	struct pt_regs regs;
-
-	memset(&regs, 0, sizeof(regs));
-
-	regs.ebx = (unsigned long) fn;
-	regs.edx = (unsigned long) arg;
-
-	regs.xds = __USER_DS;
-	regs.xes = __USER_DS;
-	regs.xfs = __KERNEL_PERCPU;
-	regs.orig_eax = -1;
-	regs.eip = (unsigned long) kernel_thread_helper;
-	regs.xcs = __KERNEL_CS | get_kernel_rpl();
-	regs.eflags = X86_EFLAGS_IF | X86_EFLAGS_SF | X86_EFLAGS_PF | 0x2;
-
-	/* Ok, create the new process.. */
-	return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, &regs, 0, NULL, NULL);
-}
-EXPORT_SYMBOL(kernel_thread);
-
-/*
- * Free current thread data structures etc..
- */
-void exit_thread(void)
-{
-	/* The process may have allocated an io port bitmap... nuke it. */
-	if (unlikely(test_thread_flag(TIF_IO_BITMAP))) {
-		struct task_struct *tsk = current;
-		struct thread_struct *t = &tsk->thread;
-		int cpu = get_cpu();
-		struct tss_struct *tss = &per_cpu(init_tss, cpu);
-
-		kfree(t->io_bitmap_ptr);
-		t->io_bitmap_ptr = NULL;
-		clear_thread_flag(TIF_IO_BITMAP);
-		/*
-		 * Careful, clear this in the TSS too:
-		 */
-		memset(tss->io_bitmap, 0xff, tss->io_bitmap_max);
-		t->io_bitmap_max = 0;
-		tss->io_bitmap_owner = NULL;
-		tss->io_bitmap_max = 0;
-		tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET;
-		put_cpu();
-	}
-}
-
-void flush_thread(void)
-{
-	struct task_struct *tsk = current;
-
-	memset(tsk->thread.debugreg, 0, sizeof(unsigned long)*8);
-	memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array));	
-	clear_tsk_thread_flag(tsk, TIF_DEBUG);
-	/*
-	 * Forget coprocessor state..
-	 */
-	clear_fpu(tsk);
-	clear_used_math();
-}
-
-void release_thread(struct task_struct *dead_task)
-{
-	BUG_ON(dead_task->mm);
-	release_vm86_irqs(dead_task);
-}
-
-/*
- * This gets called before we allocate a new thread and copy
- * the current task into it.
- */
-void prepare_to_copy(struct task_struct *tsk)
-{
-	unlazy_fpu(tsk);
-}
-
-int copy_thread(int nr, unsigned long clone_flags, unsigned long esp,
-	unsigned long unused,
-	struct task_struct * p, struct pt_regs * regs)
-{
-	struct pt_regs * childregs;
-	struct task_struct *tsk;
-	int err;
-
-	childregs = task_pt_regs(p);
-	*childregs = *regs;
-	childregs->eax = 0;
-	childregs->esp = esp;
-
-	p->thread.esp = (unsigned long) childregs;
-	p->thread.esp0 = (unsigned long) (childregs+1);
-
-	p->thread.eip = (unsigned long) ret_from_fork;
-
-	savesegment(gs,p->thread.gs);
-
-	tsk = current;
-	if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) {
-		p->thread.io_bitmap_ptr = kmemdup(tsk->thread.io_bitmap_ptr,
-						IO_BITMAP_BYTES, GFP_KERNEL);
-		if (!p->thread.io_bitmap_ptr) {
-			p->thread.io_bitmap_max = 0;
-			return -ENOMEM;
-		}
-		set_tsk_thread_flag(p, TIF_IO_BITMAP);
-	}
-
-	/*
-	 * Set a new TLS for the child thread?
-	 */
-	if (clone_flags & CLONE_SETTLS) {
-		struct desc_struct *desc;
-		struct user_desc info;
-		int idx;
-
-		err = -EFAULT;
-		if (copy_from_user(&info, (void __user *)childregs->esi, sizeof(info)))
-			goto out;
-		err = -EINVAL;
-		if (LDT_empty(&info))
-			goto out;
-
-		idx = info.entry_number;
-		if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
-			goto out;
-
-		desc = p->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
-		desc->a = LDT_entry_a(&info);
-		desc->b = LDT_entry_b(&info);
-	}
-
-	err = 0;
- out:
-	if (err && p->thread.io_bitmap_ptr) {
-		kfree(p->thread.io_bitmap_ptr);
-		p->thread.io_bitmap_max = 0;
-	}
-	return err;
-}
-
-/*
- * fill in the user structure for a core dump..
- */
-void dump_thread(struct pt_regs * regs, struct user * dump)
-{
-	int i;
-
-/* changed the size calculations - should hopefully work better. lbt */
-	dump->magic = CMAGIC;
-	dump->start_code = 0;
-	dump->start_stack = regs->esp & ~(PAGE_SIZE - 1);
-	dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT;
-	dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT;
-	dump->u_dsize -= dump->u_tsize;
-	dump->u_ssize = 0;
-	for (i = 0; i < 8; i++)
-		dump->u_debugreg[i] = current->thread.debugreg[i];  
-
-	if (dump->start_stack < TASK_SIZE)
-		dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT;
-
-	dump->regs.ebx = regs->ebx;
-	dump->regs.ecx = regs->ecx;
-	dump->regs.edx = regs->edx;
-	dump->regs.esi = regs->esi;
-	dump->regs.edi = regs->edi;
-	dump->regs.ebp = regs->ebp;
-	dump->regs.eax = regs->eax;
-	dump->regs.ds = regs->xds;
-	dump->regs.es = regs->xes;
-	dump->regs.fs = regs->xfs;
-	savesegment(gs,dump->regs.gs);
-	dump->regs.orig_eax = regs->orig_eax;
-	dump->regs.eip = regs->eip;
-	dump->regs.cs = regs->xcs;
-	dump->regs.eflags = regs->eflags;
-	dump->regs.esp = regs->esp;
-	dump->regs.ss = regs->xss;
-
-	dump->u_fpvalid = dump_fpu (regs, &dump->i387);
-}
-EXPORT_SYMBOL(dump_thread);
-
-/* 
- * Capture the user space registers if the task is not running (in user space)
- */
-int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs)
-{
-	struct pt_regs ptregs = *task_pt_regs(tsk);
-	ptregs.xcs &= 0xffff;
-	ptregs.xds &= 0xffff;
-	ptregs.xes &= 0xffff;
-	ptregs.xss &= 0xffff;
-
-	elf_core_copy_regs(regs, &ptregs);
-
-	return 1;
-}
-
-#ifdef CONFIG_SECCOMP
-void hard_disable_TSC(void)
-{
-	write_cr4(read_cr4() | X86_CR4_TSD);
-}
-void disable_TSC(void)
-{
-	preempt_disable();
-	if (!test_and_set_thread_flag(TIF_NOTSC))
-		/*
-		 * Must flip the CPU state synchronously with
-		 * TIF_NOTSC in the current running context.
-		 */
-		hard_disable_TSC();
-	preempt_enable();
-}
-void hard_enable_TSC(void)
-{
-	write_cr4(read_cr4() & ~X86_CR4_TSD);
-}
-#endif /* CONFIG_SECCOMP */
-
-static noinline void
-__switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p,
-		 struct tss_struct *tss)
-{
-	struct thread_struct *next;
-
-	next = &next_p->thread;
-
-	if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
-		set_debugreg(next->debugreg[0], 0);
-		set_debugreg(next->debugreg[1], 1);
-		set_debugreg(next->debugreg[2], 2);
-		set_debugreg(next->debugreg[3], 3);
-		/* no 4 and 5 */
-		set_debugreg(next->debugreg[6], 6);
-		set_debugreg(next->debugreg[7], 7);
-	}
-
-#ifdef CONFIG_SECCOMP
-	if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^
-	    test_tsk_thread_flag(next_p, TIF_NOTSC)) {
-		/* prev and next are different */
-		if (test_tsk_thread_flag(next_p, TIF_NOTSC))
-			hard_disable_TSC();
-		else
-			hard_enable_TSC();
-	}
-#endif
-
-	if (!test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) {
-		/*
-		 * Disable the bitmap via an invalid offset. We still cache
-		 * the previous bitmap owner and the IO bitmap contents:
-		 */
-		tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET;
-		return;
-	}
-
-	if (likely(next == tss->io_bitmap_owner)) {
-		/*
-		 * Previous owner of the bitmap (hence the bitmap content)
-		 * matches the next task, we dont have to do anything but
-		 * to set a valid offset in the TSS:
-		 */
-		tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET;
-		return;
-	}
-	/*
-	 * Lazy TSS's I/O bitmap copy. We set an invalid offset here
-	 * and we let the task to get a GPF in case an I/O instruction
-	 * is performed.  The handler of the GPF will verify that the
-	 * faulting task has a valid I/O bitmap and, it true, does the
-	 * real copy and restart the instruction.  This will save us
-	 * redundant copies when the currently switched task does not
-	 * perform any I/O during its timeslice.
-	 */
-	tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;
-}
-
-/*
- *	switch_to(x,yn) should switch tasks from x to y.
- *
- * We fsave/fwait so that an exception goes off at the right time
- * (as a call from the fsave or fwait in effect) rather than to
- * the wrong process. Lazy FP saving no longer makes any sense
- * with modern CPU's, and this simplifies a lot of things (SMP
- * and UP become the same).
- *
- * NOTE! We used to use the x86 hardware context switching. The
- * reason for not using it any more becomes apparent when you
- * try to recover gracefully from saved state that is no longer
- * valid (stale segment register values in particular). With the
- * hardware task-switch, there is no way to fix up bad state in
- * a reasonable manner.
- *
- * The fact that Intel documents the hardware task-switching to
- * be slow is a fairly red herring - this code is not noticeably
- * faster. However, there _is_ some room for improvement here,
- * so the performance issues may eventually be a valid point.
- * More important, however, is the fact that this allows us much
- * more flexibility.
- *
- * The return value (in %eax) will be the "prev" task after
- * the task-switch, and shows up in ret_from_fork in entry.S,
- * for example.
- */
-struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct task_struct *next_p)
-{
-	struct thread_struct *prev = &prev_p->thread,
-				 *next = &next_p->thread;
-	int cpu = smp_processor_id();
-	struct tss_struct *tss = &per_cpu(init_tss, cpu);
-
-	/* never put a printk in __switch_to... printk() calls wake_up*() indirectly */
-
-	__unlazy_fpu(prev_p);
-
-
-	/* we're going to use this soon, after a few expensive things */
-	if (next_p->fpu_counter > 5)
-		prefetch(&next->i387.fxsave);
-
-	/*
-	 * Reload esp0.
-	 */
-	load_esp0(tss, next);
-
-	/*
-	 * Save away %gs. No need to save %fs, as it was saved on the
-	 * stack on entry.  No need to save %es and %ds, as those are
-	 * always kernel segments while inside the kernel.  Doing this
-	 * before setting the new TLS descriptors avoids the situation
-	 * where we temporarily have non-reloadable segments in %fs
-	 * and %gs.  This could be an issue if the NMI handler ever
-	 * used %fs or %gs (it does not today), or if the kernel is
-	 * running inside of a hypervisor layer.
-	 */
-	savesegment(gs, prev->gs);
-
-	/*
-	 * Load the per-thread Thread-Local Storage descriptor.
-	 */
-	load_TLS(next, cpu);
-
-	/*
-	 * Restore IOPL if needed.  In normal use, the flags restore
-	 * in the switch assembly will handle this.  But if the kernel
-	 * is running virtualized at a non-zero CPL, the popf will
-	 * not restore flags, so it must be done in a separate step.
-	 */
-	if (get_kernel_rpl() && unlikely(prev->iopl != next->iopl))
-		set_iopl_mask(next->iopl);
-
-	/*
-	 * Now maybe handle debug registers and/or IO bitmaps
-	 */
-	if (unlikely(task_thread_info(prev_p)->flags & _TIF_WORK_CTXSW_PREV ||
-		     task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT))
-		__switch_to_xtra(prev_p, next_p, tss);
-
-	/*
-	 * Leave lazy mode, flushing any hypercalls made here.
-	 * This must be done before restoring TLS segments so
-	 * the GDT and LDT are properly updated, and must be
-	 * done before math_state_restore, so the TS bit is up
-	 * to date.
-	 */
-	arch_leave_lazy_cpu_mode();
-
-	/* If the task has used fpu the last 5 timeslices, just do a full
-	 * restore of the math state immediately to avoid the trap; the
-	 * chances of needing FPU soon are obviously high now
-	 */
-	if (next_p->fpu_counter > 5)
-		math_state_restore();
-
-	/*
-	 * Restore %gs if needed (which is common)
-	 */
-	if (prev->gs | next->gs)
-		loadsegment(gs, next->gs);
-
-	x86_write_percpu(current_task, next_p);
-
-	return prev_p;
-}
-
-asmlinkage int sys_fork(struct pt_regs regs)
-{
-	return do_fork(SIGCHLD, regs.esp, &regs, 0, NULL, NULL);
-}
-
-asmlinkage int sys_clone(struct pt_regs regs)
-{
-	unsigned long clone_flags;
-	unsigned long newsp;
-	int __user *parent_tidptr, *child_tidptr;
-
-	clone_flags = regs.ebx;
-	newsp = regs.ecx;
-	parent_tidptr = (int __user *)regs.edx;
-	child_tidptr = (int __user *)regs.edi;
-	if (!newsp)
-		newsp = regs.esp;
-	return do_fork(clone_flags, newsp, &regs, 0, parent_tidptr, child_tidptr);
-}
-
-/*
- * This is trivial, and on the face of it looks like it
- * could equally well be done in user mode.
- *
- * Not so, for quite unobvious reasons - register pressure.
- * In user mode vfork() cannot have a stack frame, and if
- * done by calling the "clone()" system call directly, you
- * do not have enough call-clobbered registers to hold all
- * the information you need.
- */
-asmlinkage int sys_vfork(struct pt_regs regs)
-{
-	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.esp, &regs, 0, NULL, NULL);
-}
-
-/*
- * sys_execve() executes a new program.
- */
-asmlinkage int sys_execve(struct pt_regs regs)
-{
-	int error;
-	char * filename;
-
-	filename = getname((char __user *) regs.ebx);
-	error = PTR_ERR(filename);
-	if (IS_ERR(filename))
-		goto out;
-	error = do_execve(filename,
-			(char __user * __user *) regs.ecx,
-			(char __user * __user *) regs.edx,
-			&regs);
-	if (error == 0) {
-		task_lock(current);
-		current->ptrace &= ~PT_DTRACE;
-		task_unlock(current);
-		/* Make sure we don't return using sysenter.. */
-		set_thread_flag(TIF_IRET);
-	}
-	putname(filename);
-out:
-	return error;
-}
-
-#define top_esp                (THREAD_SIZE - sizeof(unsigned long))
-#define top_ebp                (THREAD_SIZE - 2*sizeof(unsigned long))
-
-unsigned long get_wchan(struct task_struct *p)
-{
-	unsigned long ebp, esp, eip;
-	unsigned long stack_page;
-	int count = 0;
-	if (!p || p == current || p->state == TASK_RUNNING)
-		return 0;
-	stack_page = (unsigned long)task_stack_page(p);
-	esp = p->thread.esp;
-	if (!stack_page || esp < stack_page || esp > top_esp+stack_page)
-		return 0;
-	/* include/asm-i386/system.h:switch_to() pushes ebp last. */
-	ebp = *(unsigned long *) esp;
-	do {
-		if (ebp < stack_page || ebp > top_ebp+stack_page)
-			return 0;
-		eip = *(unsigned long *) (ebp+4);
-		if (!in_sched_functions(eip))
-			return eip;
-		ebp = *(unsigned long *) ebp;
-	} while (count++ < 16);
-	return 0;
-}
-
-/*
- * sys_alloc_thread_area: get a yet unused TLS descriptor index.
- */
-static int get_free_idx(void)
-{
-	struct thread_struct *t = &current->thread;
-	int idx;
-
-	for (idx = 0; idx < GDT_ENTRY_TLS_ENTRIES; idx++)
-		if (desc_empty(t->tls_array + idx))
-			return idx + GDT_ENTRY_TLS_MIN;
-	return -ESRCH;
-}
-
-/*
- * Set a given TLS descriptor:
- */
-asmlinkage int sys_set_thread_area(struct user_desc __user *u_info)
-{
-	struct thread_struct *t = &current->thread;
-	struct user_desc info;
-	struct desc_struct *desc;
-	int cpu, idx;
-
-	if (copy_from_user(&info, u_info, sizeof(info)))
-		return -EFAULT;
-	idx = info.entry_number;
-
-	/*
-	 * index -1 means the kernel should try to find and
-	 * allocate an empty descriptor:
-	 */
-	if (idx == -1) {
-		idx = get_free_idx();
-		if (idx < 0)
-			return idx;
-		if (put_user(idx, &u_info->entry_number))
-			return -EFAULT;
-	}
-
-	if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
-		return -EINVAL;
-
-	desc = t->tls_array + idx - GDT_ENTRY_TLS_MIN;
-
-	/*
-	 * We must not get preempted while modifying the TLS.
-	 */
-	cpu = get_cpu();
-
-	if (LDT_empty(&info)) {
-		desc->a = 0;
-		desc->b = 0;
-	} else {
-		desc->a = LDT_entry_a(&info);
-		desc->b = LDT_entry_b(&info);
-	}
-	load_TLS(t, cpu);
-
-	put_cpu();
-
-	return 0;
-}
-
-/*
- * Get the current Thread-Local Storage area:
- */
-
-#define GET_BASE(desc) ( \
-	(((desc)->a >> 16) & 0x0000ffff) | \
-	(((desc)->b << 16) & 0x00ff0000) | \
-	( (desc)->b        & 0xff000000)   )
-
-#define GET_LIMIT(desc) ( \
-	((desc)->a & 0x0ffff) | \
-	 ((desc)->b & 0xf0000) )
-	
-#define GET_32BIT(desc)		(((desc)->b >> 22) & 1)
-#define GET_CONTENTS(desc)	(((desc)->b >> 10) & 3)
-#define GET_WRITABLE(desc)	(((desc)->b >>  9) & 1)
-#define GET_LIMIT_PAGES(desc)	(((desc)->b >> 23) & 1)
-#define GET_PRESENT(desc)	(((desc)->b >> 15) & 1)
-#define GET_USEABLE(desc)	(((desc)->b >> 20) & 1)
-
-asmlinkage int sys_get_thread_area(struct user_desc __user *u_info)
-{
-	struct user_desc info;
-	struct desc_struct *desc;
-	int idx;
-
-	if (get_user(idx, &u_info->entry_number))
-		return -EFAULT;
-	if (idx < GDT_ENTRY_TLS_MIN || idx > GDT_ENTRY_TLS_MAX)
-		return -EINVAL;
-
-	memset(&info, 0, sizeof(info));
-
-	desc = current->thread.tls_array + idx - GDT_ENTRY_TLS_MIN;
-
-	info.entry_number = idx;
-	info.base_addr = GET_BASE(desc);
-	info.limit = GET_LIMIT(desc);
-	info.seg_32bit = GET_32BIT(desc);
-	info.contents = GET_CONTENTS(desc);
-	info.read_exec_only = !GET_WRITABLE(desc);
-	info.limit_in_pages = GET_LIMIT_PAGES(desc);
-	info.seg_not_present = !GET_PRESENT(desc);
-	info.useable = GET_USEABLE(desc);
-
-	if (copy_to_user(u_info, &info, sizeof(info)))
-		return -EFAULT;
-	return 0;
-}
-
-unsigned long arch_align_stack(unsigned long sp)
-{
-	if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
-		sp -= get_random_int() % 8192;
-	return sp & ~0xf;
-}