2 * Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
9 #include <linux/slab.h>
10 #include <linux/sched.h>
13 #include <linux/init.h>
15 unsigned int __read_mostly vdso_enabled = 1;
16 unsigned long um_vdso_addr;
18 extern unsigned long task_size;
19 extern char vdso_start[], vdso_end[];
21 static struct page **vdsop;
23 static int __init init_vdso(void)
27 BUG_ON(vdso_end - vdso_start > PAGE_SIZE);
29 um_vdso_addr = task_size - PAGE_SIZE;
31 vdsop = kmalloc(GFP_KERNEL, sizeof(struct page *));
35 um_vdso = alloc_page(GFP_KERNEL);
42 copy_page(page_address(um_vdso), vdso_start);
48 printk(KERN_ERR "Cannot allocate vdso\n");
53 subsys_initcall(init_vdso);
55 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
58 struct mm_struct *mm = current->mm;
63 down_write(&mm->mmap_sem);
65 err = install_special_mapping(mm, um_vdso_addr, PAGE_SIZE,
67 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC|
71 up_write(&mm->mmap_sem);