i386: prepare shared kernel/ldt.c

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

1 files changed, 0 insertions, 250 deletions

diff --git a/arch/i386/kernel/ldt.c b/arch/i386/kernel/ldt.c
deleted file mode 100644
index e0b2d17f4f10..000000000000
--- a/arch/i386/kernel/ldt.c
+++ /dev/null
@@ -1,250 +0,0 @@
-/*
- * linux/arch/i386/kernel/ldt.c
- *
- * Copyright (C) 1992 Krishna Balasubramanian and Linus Torvalds
- * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com>
- */
-
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/string.h>
-#include <linux/mm.h>
-#include <linux/smp.h>
-#include <linux/vmalloc.h>
-#include <linux/slab.h>
-
-#include <asm/uaccess.h>
-#include <asm/system.h>
-#include <asm/ldt.h>
-#include <asm/desc.h>
-#include <asm/mmu_context.h>
-
-#ifdef CONFIG_SMP /* avoids "defined but not used" warnig */
-static void flush_ldt(void *null)
-{
-	if (current->active_mm)
-		load_LDT(&current->active_mm->context);
-}
-#endif
-
-static int alloc_ldt(mm_context_t *pc, int mincount, int reload)
-{
-	void *oldldt;
-	void *newldt;
-	int oldsize;
-
-	if (mincount <= pc->size)
-		return 0;
-	oldsize = pc->size;
-	mincount = (mincount+511)&(~511);
-	if (mincount*LDT_ENTRY_SIZE > PAGE_SIZE)
-		newldt = vmalloc(mincount*LDT_ENTRY_SIZE);
-	else
-		newldt = kmalloc(mincount*LDT_ENTRY_SIZE, GFP_KERNEL);
-
-	if (!newldt)
-		return -ENOMEM;
-
-	if (oldsize)
-		memcpy(newldt, pc->ldt, oldsize*LDT_ENTRY_SIZE);
-	oldldt = pc->ldt;
-	memset(newldt+oldsize*LDT_ENTRY_SIZE, 0, (mincount-oldsize)*LDT_ENTRY_SIZE);
-	pc->ldt = newldt;
-	wmb();
-	pc->size = mincount;
-	wmb();
-
-	if (reload) {
-#ifdef CONFIG_SMP
-		cpumask_t mask;
-		preempt_disable();
-		load_LDT(pc);
-		mask = cpumask_of_cpu(smp_processor_id());
-		if (!cpus_equal(current->mm->cpu_vm_mask, mask))
-			smp_call_function(flush_ldt, NULL, 1, 1);
-		preempt_enable();
-#else
-		load_LDT(pc);
-#endif
-	}
-	if (oldsize) {
-		if (oldsize*LDT_ENTRY_SIZE > PAGE_SIZE)
-			vfree(oldldt);
-		else
-			kfree(oldldt);
-	}
-	return 0;
-}
-
-static inline int copy_ldt(mm_context_t *new, mm_context_t *old)
-{
-	int err = alloc_ldt(new, old->size, 0);
-	if (err < 0)
-		return err;
-	memcpy(new->ldt, old->ldt, old->size*LDT_ENTRY_SIZE);
-	return 0;
-}
-
-/*
- * we do not have to muck with descriptors here, that is
- * done in switch_mm() as needed.
- */
-int init_new_context(struct task_struct *tsk, struct mm_struct *mm)
-{
-	struct mm_struct * old_mm;
-	int retval = 0;
-
-	init_MUTEX(&mm->context.sem);
-	mm->context.size = 0;
-	old_mm = current->mm;
-	if (old_mm && old_mm->context.size > 0) {
-		down(&old_mm->context.sem);
-		retval = copy_ldt(&mm->context, &old_mm->context);
-		up(&old_mm->context.sem);
-	}
-	return retval;
-}
-
-/*
- * No need to lock the MM as we are the last user
- */
-void destroy_context(struct mm_struct *mm)
-{
-	if (mm->context.size) {
-		if (mm == current->active_mm)
-			clear_LDT();
-		if (mm->context.size*LDT_ENTRY_SIZE > PAGE_SIZE)
-			vfree(mm->context.ldt);
-		else
-			kfree(mm->context.ldt);
-		mm->context.size = 0;
-	}
-}
-
-static int read_ldt(void __user * ptr, unsigned long bytecount)
-{
-	int err;
-	unsigned long size;
-	struct mm_struct * mm = current->mm;
-
-	if (!mm->context.size)
-		return 0;
-	if (bytecount > LDT_ENTRY_SIZE*LDT_ENTRIES)
-		bytecount = LDT_ENTRY_SIZE*LDT_ENTRIES;
-
-	down(&mm->context.sem);
-	size = mm->context.size*LDT_ENTRY_SIZE;
-	if (size > bytecount)
-		size = bytecount;
-
-	err = 0;
-	if (copy_to_user(ptr, mm->context.ldt, size))
-		err = -EFAULT;
-	up(&mm->context.sem);
-	if (err < 0)
-		goto error_return;
-	if (size != bytecount) {
-		/* zero-fill the rest */
-		if (clear_user(ptr+size, bytecount-size) != 0) {
-			err = -EFAULT;
-			goto error_return;
-		}
-	}
-	return bytecount;
-error_return:
-	return err;
-}
-
-static int read_default_ldt(void __user * ptr, unsigned long bytecount)
-{
-	int err;
-	unsigned long size;
-
-	err = 0;
-	size = 5*sizeof(struct desc_struct);
-	if (size > bytecount)
-		size = bytecount;
-
-	err = size;
-	if (clear_user(ptr, size))
-		err = -EFAULT;
-
-	return err;
-}
-
-static int write_ldt(void __user * ptr, unsigned long bytecount, int oldmode)
-{
-	struct mm_struct * mm = current->mm;
-	__u32 entry_1, entry_2;
-	int error;
-	struct user_desc ldt_info;
-
-	error = -EINVAL;
-	if (bytecount != sizeof(ldt_info))
-		goto out;
-	error = -EFAULT; 	
-	if (copy_from_user(&ldt_info, ptr, sizeof(ldt_info)))
-		goto out;
-
-	error = -EINVAL;
-	if (ldt_info.entry_number >= LDT_ENTRIES)
-		goto out;
-	if (ldt_info.contents == 3) {
-		if (oldmode)
-			goto out;
-		if (ldt_info.seg_not_present == 0)
-			goto out;
-	}
-
-	down(&mm->context.sem);
-	if (ldt_info.entry_number >= mm->context.size) {
-		error = alloc_ldt(&current->mm->context, ldt_info.entry_number+1, 1);
-		if (error < 0)
-			goto out_unlock;
-	}
-
-   	/* Allow LDTs to be cleared by the user. */
-   	if (ldt_info.base_addr == 0 && ldt_info.limit == 0) {
-		if (oldmode || LDT_empty(&ldt_info)) {
-			entry_1 = 0;
-			entry_2 = 0;
-			goto install;
-		}
-	}
-
-	entry_1 = LDT_entry_a(&ldt_info);
-	entry_2 = LDT_entry_b(&ldt_info);
-	if (oldmode)
-		entry_2 &= ~(1 << 20);
-
-	/* Install the new entry ...  */
-install:
-	write_ldt_entry(mm->context.ldt, ldt_info.entry_number, entry_1, entry_2);
-	error = 0;
-
-out_unlock:
-	up(&mm->context.sem);
-out:
-	return error;
-}
-
-asmlinkage int sys_modify_ldt(int func, void __user *ptr, unsigned long bytecount)
-{
-	int ret = -ENOSYS;
-
-	switch (func) {
-	case 0:
-		ret = read_ldt(ptr, bytecount);
-		break;
-	case 1:
-		ret = write_ldt(ptr, bytecount, 1);
-		break;
-	case 2:
-		ret = read_default_ldt(ptr, bytecount);
-		break;
-	case 0x11:
-		ret = write_ldt(ptr, bytecount, 0);
-		break;
-	}
-	return ret;
-}