kernel-fxtec-pro1x/drivers/xen/xenfs/super.c
Alex Zeffertt 1107ba885e xen: add xenfs to allow usermode <-> Xen interaction
The xenfs filesystem exports various interfaces to usermode.  Initially
this exports a file to allow usermode to interact with xenbus/xenstore.

Traditionally this appeared in /proc/xen.  Rather than extending procfs,
this patch adds a backward-compat mountpoint on /proc/xen, and provides
a xenfs filesystem which can be mounted there.

Signed-off-by: Alex Zeffertt <alex.zeffertt@eu.citrix.com>
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-08 08:30:59 -08:00

64 lines
1.5 KiB
C

/*
* xenfs.c - a filesystem for passing info between the a domain and
* the hypervisor.
*
* 2008-10-07 Alex Zeffertt Replaced /proc/xen/xenbus with xenfs filesystem
* and /proc/xen compatibility mount point.
* Turned xenfs into a loadable module.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/magic.h>
#include "xenfs.h"
#include <asm/xen/hypervisor.h>
MODULE_DESCRIPTION("Xen filesystem");
MODULE_LICENSE("GPL");
static int xenfs_fill_super(struct super_block *sb, void *data, int silent)
{
static struct tree_descr xenfs_files[] = {
[2] = {"xenbus", &xenbus_file_ops, S_IRUSR|S_IWUSR},
{""},
};
return simple_fill_super(sb, XENFS_SUPER_MAGIC, xenfs_files);
}
static int xenfs_get_sb(struct file_system_type *fs_type,
int flags, const char *dev_name,
void *data, struct vfsmount *mnt)
{
return get_sb_single(fs_type, flags, data, xenfs_fill_super, mnt);
}
static struct file_system_type xenfs_type = {
.owner = THIS_MODULE,
.name = "xenfs",
.get_sb = xenfs_get_sb,
.kill_sb = kill_litter_super,
};
static int __init xenfs_init(void)
{
if (xen_pv_domain())
return register_filesystem(&xenfs_type);
printk(KERN_INFO "XENFS: not registering filesystem on non-xen platform\n");
return 0;
}
static void __exit xenfs_exit(void)
{
if (xen_pv_domain())
unregister_filesystem(&xenfs_type);
}
module_init(xenfs_init);
module_exit(xenfs_exit);