static int xenkbd_connect_backend(struct xenbus_device *dev,
struct xenkbd_info *info)
{
int ret, evtchn;
struct xenbus_transaction xbt;
ret = xenbus_alloc_evtchn(dev, &evtchn);
if (ret)
return ret;
ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
0, dev->devicetype, info);
if (ret < 0) {
xenbus_free_evtchn(dev, evtchn);
xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
return ret;
}
info->irq = ret;
again:
ret = xenbus_transaction_start(&xbt);
if (ret) {
xenbus_dev_fatal(dev, ret, "starting transaction");
return ret;
}
ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
virt_to_mfn(info->page));
if (ret)
goto error_xenbus;
ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
evtchn);
if (ret)
goto error_xenbus;
ret = xenbus_transaction_end(xbt, 0);
if (ret) {
if (ret == -EAGAIN)
goto again;
xenbus_dev_fatal(dev, ret, "completing transaction");
return ret;
}
xenbus_switch_state(dev, XenbusStateInitialised);
return 0;
error_xenbus:
xenbus_transaction_end(xbt, 1);
xenbus_dev_fatal(dev, ret, "writing xenstore");
return ret;
}
/* Release a reference to a pcifront device */
static void
put_pdev(struct pcifront_device *pdev)
{
if (--pdev->ref_cnt > 0)
return;
DPRINTF("freeing pdev @ 0x%p (ref_cnt=%d)\n", pdev, pdev->ref_cnt);
if (pdev->evtchn != INVALID_EVTCHN)
xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
if (pdev->gnt_ref != INVALID_GRANT_REF)
gnttab_end_foreign_access(pdev->gnt_ref, 0, (void *)pdev->sh_info);
pdev->xdev->data = NULL;
free(pdev, M_DEVBUF);
}
static void free_pdev(struct pcifront_device *pdev)
{
dev_dbg(&pdev->xdev->dev, "freeing pdev @ 0x%p\n", pdev);
pcifront_free_roots(pdev);
/*For PCIE_AER error handling job*/
flush_scheduled_work();
unbind_from_irqhandler(pdev->evtchn, pdev);
if (pdev->evtchn != INVALID_EVTCHN)
xenbus_free_evtchn(pdev->xdev, pdev->evtchn);
if (pdev->gnt_ref != INVALID_GRANT_REF)
gnttab_end_foreign_access(pdev->gnt_ref,
(unsigned long)pdev->sh_info);
dev_set_drvdata(&pdev->xdev->dev, NULL);
kfree(pdev);
}
static int xenkbd_connect_backend(struct xenbus_device *dev,
struct xenkbd_info *info)
{
int ret, evtchn;
struct xenbus_transaction xbt;
ret = gnttab_grant_foreign_access(dev->otherend_id,
virt_to_gfn(info->page), 0);
if (ret < 0)
return ret;
info->gref = ret;
ret = xenbus_alloc_evtchn(dev, &evtchn);
if (ret)
goto error_grant;
ret = bind_evtchn_to_irqhandler(evtchn, input_handler,
0, dev->devicetype, info);
if (ret < 0) {
xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
goto error_evtchan;
}
info->irq = ret;
again:
ret = xenbus_transaction_start(&xbt);
if (ret) {
xenbus_dev_fatal(dev, ret, "starting transaction");
goto error_irqh;
}
ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu",
virt_to_gfn(info->page));
if (ret)
goto error_xenbus;
ret = xenbus_printf(xbt, dev->nodename, "page-gref", "%u", info->gref);
if (ret)
goto error_xenbus;
ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u",
evtchn);
if (ret)
goto error_xenbus;
ret = xenbus_transaction_end(xbt, 0);
if (ret) {
if (ret == -EAGAIN)
goto again;
xenbus_dev_fatal(dev, ret, "completing transaction");
goto error_irqh;
}
xenbus_switch_state(dev, XenbusStateInitialised);
return 0;
error_xenbus:
xenbus_transaction_end(xbt, 1);
xenbus_dev_fatal(dev, ret, "writing xenstore");
error_irqh:
unbind_from_irqhandler(info->irq, info);
info->irq = -1;
error_evtchan:
xenbus_free_evtchn(dev, evtchn);
error_grant:
gnttab_end_foreign_access(info->gref, 0, 0UL);
info->gref = -1;
return ret;
}
/**
* Connect the OpenXT input device to the corresponding backend.
*
* @param dev The device to be connected.
* @param info The information structure that corresponds to the given device.
*
* @return int Zero on success, or an error code on failure.
*/
static int oxtkbd_connect_backend(struct xenbus_device *dev,
struct openxt_kbd_info *info)
{
int ret, evtchn;
struct xenbus_transaction xbt;
//To communicate with the backend, we'll share a single page of memory
//We'll start this process by granting out our "shared page".
ret = gnttab_grant_foreign_access(dev->otherend_id, virt_to_mfn(info->page), 0);
if (ret < 0)
return ret;
info->gref = ret;
//Next, we'll need to create an event channel we can use to signal that data
//has changed in our shared page.
ret = xenbus_alloc_evtchn(dev, &evtchn);
if (ret)
goto error_grant;
//Bind our input handler to our event channel-- ensuring we're recieve any
//"new data" notifications.
ret = bind_evtchn_to_irqhandler(evtchn, input_handler, 0, dev->devicetype, info);
if (ret < 0) {
xenbus_dev_fatal(dev, ret, "bind_evtchn_to_irqhandler");
goto error_evtchan;
}
info->irq = ret;
again:
//Now that we've set up our shared assets, we'll need to communicate them
//to the backend. First, we'll start a xenbus transaction, so we can dump
//all of our data into the XenStore simultaneously.
ret = xenbus_transaction_start(&xbt);
if (ret) {
xenbus_dev_fatal(dev, ret, "starting transaction");
goto error_irqh;
}
//Provide a direct reference to the page. This allows backends that want
//to use foreign mappings (i.e. legacy backends) to map in the shared page
//without touching grants.
ret = xenbus_printf(xbt, dev->nodename, "page-ref", "%lu", virt_to_mfn(info->page));
if (ret)
goto error_xenbus;
//And provide our grant reference. This is the preferred way of getting the
//shared page.
ret = xenbus_printf(xbt, dev->nodename, "page-gref", "%u", info->gref);
if (ret)
goto error_xenbus;
//Provide the number for our event channel, so the backend can signal
//new informatino to us.
ret = xenbus_printf(xbt, dev->nodename, "event-channel", "%u", evtchn);
if (ret)
goto error_xenbus;
//Attempt to apply all of our changes at once.
ret = xenbus_transaction_end(xbt, 0);
//If our transaction failed...
if (ret) {
//... it may have been because the XenStore was busy. If this is the case,
//repeat out transaction until we succeed, or hit an error.
if (ret == -EAGAIN)
goto again;
//Otherwise, we couldn't connect. Bail out!
xenbus_dev_fatal(dev, ret, "completing transaction");
goto error_irqh;
}
//Finally, switch our state to "intialized", hopefully cueing the backend
//to connect.
xenbus_switch_state(dev, XenbusStateInitialised);
return 0;
error_xenbus:
xenbus_transaction_end(xbt, 1);
xenbus_dev_fatal(dev, ret, "writing xenstore");
error_irqh:
unbind_from_irqhandler(info->irq, info);
info->irq = -1;
error_evtchan:
xenbus_free_evtchn(dev, evtchn);
error_grant:
gnttab_end_foreign_access(info->gref, 0, 0UL);
info->gref = -1;
return ret;
}
