C++ xenbus_dev_fatal函数代码示例

static void connect(struct backend_info *be)
{
	int err;
	struct xenbus_device *dev = be->dev;

	rtnl_lock();

	err = xen_net_read_mac(dev, be->netif->fe_dev_addr);
	if (err) {
		xenbus_dev_fatal(dev, err, "parsing %s/mac", dev->nodename);
		goto out;
	}

	xen_net_read_rate(dev, &be->netif->credit_bytes,
			  &be->netif->credit_usec);
	be->netif->remaining_credit = be->netif->credit_bytes;

	err = connect_rings(be);
	if (err)
		goto out;

	/* May not get a kick from the frontend, so start the tx_queue now. */
	if (!netbk_can_queue(be->netif->dev))
		netif_wake_queue(be->netif->dev);

out:
	rtnl_unlock();
}

static int tpmfront_probe(struct xenbus_device *dev,
		const struct xenbus_device_id *id)
{
	struct tpm_private *priv;
	int rv;

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv) {
		xenbus_dev_fatal(dev, -ENOMEM, "allocating priv structure");
		return -ENOMEM;
	}

	rv = setup_chip(&dev->dev, priv);
	if (rv) {
		kfree(priv);
		return rv;
	}

	rv = setup_ring(dev, priv);
	if (rv) {
		tpm_remove_hardware(&dev->dev);
		ring_free(priv);
		return rv;
	}

	tpm_get_timeouts(priv->chip);

	dev_set_drvdata(&dev->dev, priv->chip);

	return rv;
}

static void backend_changed(struct xenbus_device *dev,
		enum xenbus_state backend_state)
{
	int val;

	switch (backend_state) {
	case XenbusStateInitialised:
	case XenbusStateConnected:
		if (dev->state == XenbusStateConnected)
			break;

		if (xenbus_scanf(XBT_NIL, dev->otherend,
				"feature-protocol-v2", "%d", &val) < 0)
			val = 0;
		if (!val) {
			xenbus_dev_fatal(dev, -EINVAL,
					"vTPM protocol 2 required");
			return;
		}
		xenbus_switch_state(dev, XenbusStateConnected);
		break;

	case XenbusStateClosing:
	case XenbusStateClosed:
		device_unregister(&dev->dev);
		xenbus_frontend_closed(dev);
		break;
	default:
		break;
	}
}

/**
 * Handle the creation of the hotplug script environment.  We add the script
 * and vif variables to the environment, for the benefit of the vif-* hotplug
 * scripts.
 */
static int netback_uevent(struct xenbus_device *xdev, char **envp,
			  int num_envp, char *buffer, int buffer_size)
{
	struct backend_info *be = xdev->dev.driver_data;
	netif_t *netif = be->netif;
	int i = 0, length = 0;
	char *val;

	DPRINTK("netback_uevent");

	val = xenbus_read(XBT_NIL, xdev->nodename, "script", NULL);
	if (IS_ERR(val)) {
		int err = PTR_ERR(val);
		xenbus_dev_fatal(xdev, err, "reading script");
		return err;
	}
	else {
		add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
			       &length, "script=%s", val);
		kfree(val);
	}

	add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
		       "vif=%s", netif->dev->name);

	envp[i] = NULL;

	return 0;
}

/*
 * Callback received when the frontend's state changes.
 */
static void frontend_changed(struct xenbus_device *dev,
			     enum xenbus_state frontend_state)
{
	struct backend_info *be = dev_get_drvdata(&dev->dev);
	int err;

	DPRINTK("%s", xenbus_strstate(frontend_state));

	switch (frontend_state) {
	case XenbusStateInitialising:
		if (dev->state == XenbusStateClosed) {
			pr_info(DRV_PFX "%s: prepare for reconnect\n",
				dev->nodename);
			xenbus_switch_state(dev, XenbusStateInitWait);
		}
		break;

	case XenbusStateInitialised:
	case XenbusStateConnected:
		/*
		 * Ensure we connect even when two watches fire in
		 * close succession and we miss the intermediate value
		 * of frontend_state.
		 */
		if (dev->state == XenbusStateConnected)
			break;

		/*
		 * Enforce precondition before potential leak point.
		 * xen_blkif_disconnect() is idempotent.
		 */
		xen_blkif_disconnect(be->blkif);

		err = connect_ring(be);
		if (err)
			break;
		xen_update_blkif_status(be->blkif);
		break;

	case XenbusStateClosing:
		xenbus_switch_state(dev, XenbusStateClosing);
		break;

	case XenbusStateClosed:
		xen_blkif_disconnect(be->blkif);
		xenbus_switch_state(dev, XenbusStateClosed);
		if (xenbus_dev_is_online(dev))
			break;
		/* fall through if not online */
	case XenbusStateUnknown:
		/* implies xen_blkif_disconnect() via xen_blkbk_remove() */
		device_unregister(&dev->dev);
		break;

	default:
		xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
				 frontend_state);
		break;
	}
}

static int xen_pcibk_xenbus_probe(struct xenbus_device *dev,
				const struct xenbus_device_id *id)
{
	int err = 0;
	struct xen_pcibk_device *pdev = alloc_pdev(dev);

	if (pdev == NULL) {
		err = -ENOMEM;
		xenbus_dev_fatal(dev, err,
				 "Error allocating xen_pcibk_device struct");
		goto out;
	}

	/* wait for xend to configure us */
	err = xenbus_switch_state(dev, XenbusStateInitWait);
	if (err)
		goto out;

	/* watch the backend node for backend configuration information */
	err = xenbus_watch_path(dev, dev->nodename, &pdev->be_watch,
				xen_pcibk_be_watch);
	if (err)
		goto out;

	pdev->be_watching = 1;

	/* We need to force a call to our callback here in case
	 * xend already configured us!
	 */
	xen_pcibk_be_watch(&pdev->be_watch, NULL, 0);

out:
	return err;
}

static int connect_ring(struct backend_info *be)
{
	struct xenbus_device *dev = be->dev;
	unsigned long ring_ref;
	unsigned int evtchn;
	char protocol[64] = "";
	int err;

	DPRINTK("%s", dev->otherend);

	err = xenbus_gather(XBT_NIL, dev->otherend, "ring-ref", "%lu",
			    &ring_ref, "event-channel", "%u", &evtchn, NULL);
	if (err) {
		xenbus_dev_fatal(dev, err,
				 "reading %s/ring-ref and event-channel",
				 dev->otherend);
		return err;
	}

	be->blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE;
	err = xenbus_gather(XBT_NIL, dev->otherend, "protocol",
			    "%63s", protocol, NULL);
	if (err)
		strcpy(protocol, "unspecified, assuming native");
	else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_NATIVE))
		be->blkif->blk_protocol = BLKIF_PROTOCOL_NATIVE;
	else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_32))
		be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_32;
	else if (0 == strcmp(protocol, XEN_IO_PROTO_ABI_X86_64))
		be->blkif->blk_protocol = BLKIF_PROTOCOL_X86_64;
	else {
		xenbus_dev_fatal(dev, err, "unknown fe protocol %s", protocol);
		return -1;
	}
	pr_info(DRV_PFX "ring-ref %ld, event-channel %d, protocol %d (%s)\n",
		ring_ref, evtchn, be->blkif->blk_protocol, protocol);

	/* Map the shared frame, irq etc. */
	err = xen_blkif_map(be->blkif, ring_ref, evtchn);
	if (err) {
		xenbus_dev_fatal(dev, err, "mapping ring-ref %lu port %u",
				 ring_ref, evtchn);
		return err;
	}

	return 0;
}

/**
 * Entry point to this code when a new device is created.  Allocate the basic
 * structures and the ring buffer for communication with the backend, and
 * inform the backend of the appropriate details for those.  Switch to
 * Initialised state.
 */
static int ixpfront_probe(struct xenbus_device *dev,
			  const struct xenbus_device_id *id)
{
	int err, vdevice, i;
	struct ixpfront_info *info;

	/* FIXME: Use dynamic device id if this is not set. */
	err = xenbus_scanf(XBT_NIL, dev->nodename,
			   "virtual-device", "%i", &vdevice);
	if (err != 1) {
		/* go looking in the extended area instead */
		err = xenbus_scanf(XBT_NIL, dev->nodename, "virtual-device-ext",
				   "%i", &vdevice);
		if (err != 1) {
			xenbus_dev_fatal(dev, err, "reading virtual-device");
			return err;
		}
	}

	info = kzalloc(sizeof(*info), GFP_KERNEL);
	if (!info) {
		xenbus_dev_fatal(dev, -ENOMEM, "allocating info structure");
		return -ENOMEM;
	}

	info->xbdev = dev;
	info->vdevice = vdevice;
	info->connected = IXP_STATE_DISCONNECTED;

	for (i = 0; i < IXP_RING_SIZE; i++)
		info->shadow[i].req.id = i+1;
	info->shadow[IXP_RING_SIZE-1].req.id = 0x0fffffff;

	/* Front end dir is a number, which is used as the id. */
	info->handle = simple_strtoul(strrchr(dev->nodename, '/')+1, NULL, 0);
	dev_set_drvdata(&dev->dev, info);

	err = talk_to_ixpback(dev, info);
	if (err) {
		kfree(info);
		dev_set_drvdata(&dev->dev, NULL);
		return err;
	}

	return 0;
}

/**
 * Callback received when the frontend's state changes.
 */
static void frontend_changed(struct xenbus_device *dev,
			     enum xenbus_state frontend_state)
{
	struct backend_info *be = dev_get_drvdata(&dev->dev);

	pr_debug("frontend state %s", xenbus_strstate(frontend_state));

	be->frontend_state = frontend_state;

	switch (frontend_state) {
	case XenbusStateInitialising:
		if (dev->state == XenbusStateClosed) {
			printk(KERN_INFO "%s: %s: prepare for reconnect\n",
			       __func__, dev->nodename);
			xenbus_switch_state(dev, XenbusStateInitWait);
		}
		break;

	case XenbusStateInitialised:
		break;

	case XenbusStateConnected:
		if (dev->state == XenbusStateConnected)
			break;
		backend_create_xenvif(be);
		if (be->vif)
			connect(be);
#ifdef DNP_XEN  
                be->vif->assigned_dnpVF_ID = -1;
                be->vif->dnp_net_device = NULL;
                register_vif(be->vif);                
                //Below only need if I want to start with bridge
                //switch_vif_netif(be->vif->domid,1); 
#endif
		break;

	case XenbusStateClosing:
		if (be->vif)
			kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
		disconnect_backend(dev);
		xenbus_switch_state(dev, XenbusStateClosing);
		break;

	case XenbusStateClosed:
		xenbus_switch_state(dev, XenbusStateClosed);
		if (xenbus_dev_is_online(dev))
			break;
		/* fall through if not online */
	case XenbusStateUnknown:
		device_unregister(&dev->dev);
		break;

	default:
		xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
				 frontend_state);
		break;
	}
}

static int xenkbd_connect_backend(struct xenbus_device *dev,
				  struct xenkbd_info *info)
{
	int ret;
	struct xenbus_transaction xbt;

	ret = bind_listening_port_to_irqhandler(
		dev->otherend_id, input_handler, 0, "xenkbd", info);
	if (ret < 0) {
		xenbus_dev_fatal(dev, ret,
				 "bind_listening_port_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",
			    irq_to_evtchn_port(info->irq));
	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;
}

static int setup_ixpring(struct xenbus_device *dev,
			 struct ixpfront_info *info)
{
	struct ixp_sring *sring;
	int err;

	info->ring_ref = GRANT_INVALID_REF;

	sring = (struct ixp_sring *)__get_free_page(GFP_NOIO | __GFP_HIGH);
	if (!sring) {
		xenbus_dev_fatal(dev, -ENOMEM, "allocating shared ring");
		return -ENOMEM;
	}
	SHARED_RING_INIT(sring);
	FRONT_RING_INIT(&info->ring, sring, PAGE_SIZE);

	err = xenbus_grant_ring(dev, virt_to_mfn(info->ring.sring));
	if (err < 0) {
		free_page((unsigned long)sring);
		info->ring.sring = NULL;
		goto fail;
	}
	
  	info->ring_ref = err;

	err = xenbus_alloc_evtchn(dev, &info->evtchn);
	if (err)
		goto fail;

	err = bind_evtchn_to_irqhandler(info->evtchn,
					ixp_interrupt,
					IRQF_SAMPLE_RANDOM, "ixp", info);
	if (err <= 0) {
		xenbus_dev_fatal(dev, err,
				 "bind_evtchn_to_irqhandler failed");
		goto fail;
	}
	info->irq = err;

	return 0;
fail:
	ixp_free(info, 0);
	return err;
}

/*
 * Entry point to this code when a new device is created.  Allocate the basic
 * structures, and watch the store waiting for the hotplug scripts to tell us
 * the device's physical major and minor numbers.  Switch to InitWait.
 */
static int xen_blkbk_probe(struct xenbus_device *dev,
			   const struct xenbus_device_id *id)
{
	int err;
	struct backend_info *be = kzalloc(sizeof(struct backend_info),
					  GFP_KERNEL);
	if (!be) {
		xenbus_dev_fatal(dev, -ENOMEM,
				 "allocating backend structure");
		return -ENOMEM;
	}
	be->dev = dev;
	dev_set_drvdata(&dev->dev, be);

	be->blkif = xen_blkif_alloc(dev->otherend_id);
	if (IS_ERR(be->blkif)) {
		err = PTR_ERR(be->blkif);
		be->blkif = NULL;
		xenbus_dev_fatal(dev, err, "creating block interface");
		goto fail;
	}

	/* setup back pointer */
	be->blkif->be = be;

	err = xenbus_watch_pathfmt(dev, &be->backend_watch, backend_changed,
				   "%s/%s", dev->nodename, "physical-device");
	if (err)
		goto fail;

	err = xenbus_switch_state(dev, XenbusStateInitWait);
	if (err)
		goto fail;

	return 0;

fail:
	DPRINTK("failed");
	xen_blkbk_remove(dev);
	return err;
}

static int connect_ctrl_ring(struct backend_info *be)
{
	struct xenbus_device *dev = be->dev;
	struct xenvif *vif = be->vif;
	unsigned int val;
	grant_ref_t ring_ref;
	unsigned int evtchn;
	int err;

	err = xenbus_gather(XBT_NIL, dev->otherend,
			    "ctrl-ring-ref", "%u", &val, NULL);
	if (err)
		goto done; /* The frontend does not have a control ring */

	ring_ref = val;

	err = xenbus_gather(XBT_NIL, dev->otherend,
			    "event-channel-ctrl", "%u", &val, NULL);
	if (err) {
		xenbus_dev_fatal(dev, err,
				 "reading %s/event-channel-ctrl",
				 dev->otherend);
		goto fail;
	}

	evtchn = val;

	err = xenvif_connect_ctrl(vif, ring_ref, evtchn);
	if (err) {
		xenbus_dev_fatal(dev, err,
				 "mapping shared-frame %u port %u",
				 ring_ref, evtchn);
		goto fail;
	}

done:
	return 0;

fail:
	return err;
}

static void frontend_changed(struct xenbus_device *dev, enum xenbus_state frontend_state)
{
    struct backend_info *be = dev_get_drvdata(&dev->dev);
    
	printk("\nxen: dom0:otherend id, frontend state: %s", xenbus_strstate(frontend_state));
    be->frontend_state = frontend_state;
    
	switch(frontend_state){
        case XenbusStateInitialising:{
            if (dev->state == XenbusStateClosed) {
                printk("\nxen: dom0: %s prepare for reconnect", dev->nodename);
                xenbus_switch_state(dev, XenbusStateInitWait);
             }
	         printk("\nxen: dom0: state changed to XenbusStateInitialising");
             break;
        }

        case XenbusStateInitialised:
	        printk("\nxen: dom0: front state is XenbusStateInitiallised");
            if(be->chrif)
                connect(be);
			xen_chrif_thread(be->chrif);
            break;

        case XenbusStateConnected:
           // if (dev->state == XenbusStateConnected)
           //     break;
           //map page here
	        printk("\nxen: dom0: front state XenbusStateConnected");
            break;

        case XenbusStateClosing:
            xenbus_switch_state(dev, XenbusStateClosing);
	        printk("\nxen: dom0: state changed to XenbusStateClosing");
            break;

        case XenbusStateClosed:
            //xen_chrif_disconnect(be->chrif);
            xenbus_switch_state(dev, XenbusStateClosed);
	        printk("\nxen: dom0: state changed to XenbusStateClosed");
            if (xenbus_dev_is_online(dev))
                break;

        case XenbusStateUnknown:
            //device_unregister(&dev->dev);
	        printk("\nxen: dom0: state Unknown");
            break;

        default:
            xenbus_dev_fatal(dev, -EINVAL, "default saw state %d at frontend", frontend_state);
            break;
    }
}

/**
 * Callback received when the frontend's state changes.
 */
static void frontend_changed(struct xenbus_device *dev,
			     enum xenbus_state frontend_state)
{
	struct backend_info *be = dev->dev.driver_data;

	DPRINTK("%s", xenbus_strstate(frontend_state));

	be->frontend_state = frontend_state;

	switch (frontend_state) {
	case XenbusStateInitialising:
		if (dev->state == XenbusStateClosed) {
			printk("%s: %s: prepare for reconnect\n",
			       __FUNCTION__, dev->nodename);
			if (be->netif) {
				netif_disconnect(be->netif);
				be->netif = NULL;
			}
			xenbus_switch_state(dev, XenbusStateInitWait);
		}
		break;

	case XenbusStateInitialised:
		break;

	case XenbusStateConnected:
		backend_create_netif(be);
		if (be->netif)
			connect(be);
		break;

	case XenbusStateClosing:
		xenbus_switch_state(dev, XenbusStateClosing);
		break;

	case XenbusStateClosed:
		xenbus_switch_state(dev, XenbusStateClosed);
		if (xenbus_dev_is_online(dev))
			break;
		/* fall through if not online */
	case XenbusStateUnknown:
		if (be->netif != NULL)
			kobject_uevent(&dev->dev.kobj, KOBJ_OFFLINE);
		device_unregister(&dev->dev);
		break;

	default:
		xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend",
				 frontend_state);
		break;
	}
}