/* Called by xenbus when our backend node changes state */
static void
pcifront_backend_changed(struct xenbus_device *xdev,
XenbusState be_state)
{
struct pcifront_device *pdev = xdev->data;
switch (be_state) {
case XenbusStateClosing:
DPRINTF("backend closing (%s)\n", xdev->nodename);
pcifront_disconnect(pdev);
break;
case XenbusStateClosed:
DPRINTF("backend closed (%s)\n", xdev->nodename);
pcifront_disconnect(pdev);
break;
case XenbusStateConnected:
DPRINTF("backend connected (%s)\n", xdev->nodename);
pcifront_connect(pdev);
break;
default:
break;
}
}
static int __devinit pcifront_try_connect(struct pcifront_device *pdev)
{
int err = -EFAULT;
int i, num_roots, len;
char str[64];
unsigned int domain, bus;
spin_lock(&pdev->dev_lock);
/* Only connect once */
if (xenbus_read_driver_state(pdev->xdev->nodename) !=
XenbusStateInitialised)
goto out;
err = pcifront_connect(pdev);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error connecting PCI Frontend");
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
"root_num", "%d", &num_roots);
if (err == -ENOENT) {
xenbus_dev_error(pdev->xdev, err,
"No PCI Roots found, trying 0000:00");
err = pcifront_scan_root(pdev, 0, 0);
num_roots = 0;
} else if (err != 1) {
if (err == 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading number of PCI roots");
goto out;
}
for (i = 0; i < num_roots; i++) {
len = snprintf(str, sizeof(str), "root-%d", i);
if (unlikely(len >= (sizeof(str) - 1))) {
err = -ENOMEM;
goto out;
}
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
"%x:%x", &domain, &bus);
if (err != 2) {
if (err >= 0)
err = -EINVAL;
xenbus_dev_fatal(pdev->xdev, err,
"Error reading PCI root %d", i);
goto out;
}
err = pcifront_scan_root(pdev, domain, bus);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root %04x:%02x",
domain, bus);
goto out;
}
}
err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
if (err)
goto out;
out:
spin_unlock(&pdev->dev_lock);
return err;
}
