55 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			55 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * Copyright (C) 2011 Richard Weinberger <richrd@nod.at> | ||
|  |  * | ||
|  |  * This program is free software; you can redistribute it and/or modify | ||
|  |  * it under the terms of the GNU General Public License version 2 as | ||
|  |  * published by the Free Software Foundation. | ||
|  |  */ | ||
|  | 
 | ||
|  | #include <linux/mm.h>
 | ||
|  | #include <asm/page.h>
 | ||
|  | #include <asm/mman.h>
 | ||
|  | 
 | ||
|  | static struct vm_area_struct gate_vma; | ||
|  | 
 | ||
|  | static int __init gate_vma_init(void) | ||
|  | { | ||
|  | 	if (!FIXADDR_USER_START) | ||
|  | 		return 0; | ||
|  | 
 | ||
|  | 	gate_vma.vm_mm = NULL; | ||
|  | 	gate_vma.vm_start = FIXADDR_USER_START; | ||
|  | 	gate_vma.vm_end = FIXADDR_USER_END; | ||
|  | 	gate_vma.vm_flags = VM_READ | VM_MAYREAD | VM_EXEC | VM_MAYEXEC; | ||
|  | 	gate_vma.vm_page_prot = __P101; | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | } | ||
|  | __initcall(gate_vma_init); | ||
|  | 
 | ||
|  | struct vm_area_struct *get_gate_vma(struct mm_struct *mm) | ||
|  | { | ||
|  | 	return FIXADDR_USER_START ? &gate_vma : NULL; | ||
|  | } | ||
|  | 
 | ||
|  | int in_gate_area_no_mm(unsigned long addr) | ||
|  | { | ||
|  | 	if (!FIXADDR_USER_START) | ||
|  | 		return 0; | ||
|  | 
 | ||
|  | 	if ((addr >= FIXADDR_USER_START) && (addr < FIXADDR_USER_END)) | ||
|  | 		return 1; | ||
|  | 
 | ||
|  | 	return 0; | ||
|  | } | ||
|  | 
 | ||
|  | int in_gate_area(struct mm_struct *mm, unsigned long addr) | ||
|  | { | ||
|  | 	struct vm_area_struct *vma = get_gate_vma(mm); | ||
|  | 
 | ||
|  | 	if (!vma) | ||
|  | 		return 0; | ||
|  | 
 | ||
|  | 	return (addr >= vma->vm_start) && (addr < vma->vm_end); | ||
|  | } |