linux/arch/x86/um/vdso/vma.c
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  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

  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 #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00

73 lines
1.3 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2011 Richard Weinberger <richrd@nod.at>
*/
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <asm/page.h>
#include <asm/elf.h>
#include <linux/init.h>
static unsigned int __read_mostly vdso_enabled = 1;
unsigned long um_vdso_addr;
extern unsigned long task_size;
extern char vdso_start[], vdso_end[];
static struct page **vdsop;
static int __init init_vdso(void)
{
struct page *um_vdso;
BUG_ON(vdso_end - vdso_start > PAGE_SIZE);
um_vdso_addr = task_size - PAGE_SIZE;
vdsop = kmalloc(sizeof(struct page *), GFP_KERNEL);
if (!vdsop)
goto oom;
um_vdso = alloc_page(GFP_KERNEL);
if (!um_vdso) {
kfree(vdsop);
goto oom;
}
copy_page(page_address(um_vdso), vdso_start);
*vdsop = um_vdso;
return 0;
oom:
printk(KERN_ERR "Cannot allocate vdso\n");
vdso_enabled = 0;
return -ENOMEM;
}
subsys_initcall(init_vdso);
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
int err;
struct mm_struct *mm = current->mm;
if (!vdso_enabled)
return 0;
if (down_write_killable(&mm->mmap_sem))
return -EINTR;
err = install_special_mapping(mm, um_vdso_addr, PAGE_SIZE,
VM_READ|VM_EXEC|
VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
vdsop);
up_write(&mm->mmap_sem);
return err;
}