alistair23-linux/drivers/xen/xenfs/xenstored.c
Ian Campbell 655d406a7c xen: add /proc/xen/xsd_{kva,port} to xenfs
These are used by the userspace xenstore daemon, which runs in dom0.
Xenstored is what's behind the xenfs "xenbus" filesystem.

[ Impact: provide mapping and port to usermode for xenstore ]

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
2010-10-20 16:22:26 -07:00

69 lines
1.5 KiB
C

#include <linux/slab.h>
#include <linux/types.h>
#include <linux/mm.h>
#include <linux/fs.h>
#include <xen/page.h>
#include "xenfs.h"
#include "../xenbus/xenbus_comms.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,
};