kernel/drivers/xen/xenfs/xenstored.c
2024-07-22 17:22:30 +08:00

70 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <xen/page.h>
#include <xen/xenbus.h>
#include "xenfs.h"
static ssize_t xsd_read(struct file *file, char __user *buf,
size_t size, loff_t *off)
{
const char *str = (const char *)file->private_data;
return simple_read_from_buffer(buf, size, off, str, strlen(str));
}
static int xsd_release(struct inode *inode, struct file *file)
{
kfree(file->private_data);
return 0;
}
static int xsd_kva_open(struct inode *inode, struct file *file)
{
file->private_data = (void *)kasprintf(GFP_KERNEL, "0x%p",
xen_store_interface);
if (!file->private_data)
return -ENOMEM;
return 0;
}
static int xsd_kva_mmap(struct file *file, struct vm_area_struct *vma)
{
size_t size = vma->vm_end - vma->vm_start;
if ((size > PAGE_SIZE) || (vma->vm_pgoff != 0))
return -EINVAL;
if (remap_pfn_range(vma, vma->vm_start,
virt_to_pfn(xen_store_interface),
size, vma->vm_page_prot))
return -EAGAIN;
return 0;
}
const struct file_operations xsd_kva_file_ops = {
.open = xsd_kva_open,
.mmap = xsd_kva_mmap,
.read = xsd_read,
.release = xsd_release,
};
static int xsd_port_open(struct inode *inode, struct file *file)
{
file->private_data = (void *)kasprintf(GFP_KERNEL, "%d",
xen_store_evtchn);
if (!file->private_data)
return -ENOMEM;
return 0;
}
const struct file_operations xsd_port_file_ops = {
.open = xsd_port_open,
.read = xsd_read,
.release = xsd_release,
};