| /* |
| * 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/elf.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); |
| } |
