cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

xenstored.c (1555B)

      1// SPDX-License-Identifier: GPL-2.0
      2#include <linux/slab.h>
      3#include <linux/types.h>
      4#include <linux/mm.h>
      5#include <linux/fs.h>
      6
      7#include <xen/page.h>
      8#include <xen/xenbus.h>
      9
     10#include "xenfs.h"
     11
     12static ssize_t xsd_read(struct file *file, char __user *buf,
     13			    size_t size, loff_t *off)
     14{
     15	const char *str = (const char *)file->private_data;
     16	return simple_read_from_buffer(buf, size, off, str, strlen(str));
     17}
     18
     19static int xsd_release(struct inode *inode, struct file *file)
     20{
     21	kfree(file->private_data);
     22	return 0;
     23}
     24
     25static int xsd_kva_open(struct inode *inode, struct file *file)
     26{
     27	file->private_data = (void *)kasprintf(GFP_KERNEL, "0x%p",
     28					       xen_store_interface);
     29	if (!file->private_data)
     30		return -ENOMEM;
     31	return 0;
     32}
     33
     34static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma)
     35{
     36	size_t size = vma->vm_end - vma->vm_start;
     37
     38	if ((size > PAGE_SIZE) || (vma->vm_pgoff != 0))
     39		return -EINVAL;
     40
     41	if (remap_pfn_range(vma, vma->vm_start,
     42			    virt_to_pfn(xen_store_interface),
     43			    size, vma->vm_page_prot))
     44		return -EAGAIN;
     45
     46	return 0;
     47}
     48
     49const struct file_operations xsd_kva_file_ops = {
     50	.open = xsd_kva_open,
     51	.mmap = xsd_kva_mmap,
     52	.read = xsd_read,
     53	.release = xsd_release,
     54};
     55
     56static int xsd_port_open(struct inode *inode, struct file *file)
     57{
     58	file->private_data = (void *)kasprintf(GFP_KERNEL, "%d",
     59					       xen_store_evtchn);
     60	if (!file->private_data)
     61		return -ENOMEM;
     62	return 0;
     63}
     64
     65const struct file_operations xsd_port_file_ops = {
     66	.open = xsd_port_open,
     67	.read = xsd_read,
     68	.release = xsd_release,
     69};