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>
14 #include <linux/init.h>
16 static unsigned int __read_mostly vdso_enabled = 1;
17 unsigned long um_vdso_addr;
19 extern unsigned long task_size;
20 extern char vdso_start[], vdso_end[];
22 static struct page **vdsop;
24 static int __init init_vdso(void)
28 BUG_ON(vdso_end - vdso_start > PAGE_SIZE);
30 um_vdso_addr = task_size - PAGE_SIZE;
32 vdsop = kmalloc(sizeof(struct page *), GFP_KERNEL);
36 um_vdso = alloc_page(GFP_KERNEL);
43 copy_page(page_address(um_vdso), vdso_start);
49 printk(KERN_ERR "Cannot allocate vdso\n");
54 subsys_initcall(init_vdso);
56 int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
59 struct mm_struct *mm = current->mm;
64 down_write(&mm->mmap_sem);
66 err = install_special_mapping(mm, um_vdso_addr, PAGE_SIZE,
68 VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
71 up_write(&mm->mmap_sem);