xen: add "capabilities" file

The xenfs capabilities file allows usermode to determine what
capabilities the domain has.  The only one at present is "control_d"
in a privileged domain.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
This commit is contained in:
Jeremy Fitzhardinge 2009-02-06 18:46:47 -08:00 committed by Jeremy Fitzhardinge
parent 6d02c42698
commit 818fd20673

View file

@ -20,10 +20,27 @@
MODULE_DESCRIPTION("Xen filesystem");
MODULE_LICENSE("GPL");
static ssize_t capabilities_read(struct file *file, char __user *buf,
size_t size, loff_t *off)
{
char *tmp = "";
if (xen_initial_domain())
tmp = "control_d\n";
return simple_read_from_buffer(buf, size, off, tmp, strlen(tmp));
}
static const struct file_operations capabilities_file_ops = {
.read = capabilities_read,
};
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},
[1] = {},
{ "xenbus", &xenbus_file_ops, S_IRUSR|S_IWUSR },
{ "capabilities", &capabilities_file_ops, S_IRUGO },
{""},
};