diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c index 72d2fce27a34..48b71236192d 100644 --- a/drivers/xen/pvcalls-back.c +++ b/drivers/xen/pvcalls-back.c @@ -33,9 +33,91 @@ struct pvcalls_back_global { struct semaphore frontends_lock; } pvcalls_back_global; +/* + * Per-frontend data structure. It contains pointers to the command + * ring, its event channel, a list of active sockets and a tree of + * passive sockets. + */ +struct pvcalls_fedata { + struct list_head list; + struct xenbus_device *dev; + struct xen_pvcalls_sring *sring; + struct xen_pvcalls_back_ring ring; + int irq; + struct list_head socket_mappings; + struct radix_tree_root socketpass_mappings; + struct semaphore socket_lock; +}; + +static irqreturn_t pvcalls_back_event(int irq, void *dev_id) +{ + return IRQ_HANDLED; +} + static int backend_connect(struct xenbus_device *dev) { + int err, evtchn; + grant_ref_t ring_ref; + struct pvcalls_fedata *fedata = NULL; + + fedata = kzalloc(sizeof(struct pvcalls_fedata), GFP_KERNEL); + if (!fedata) + return -ENOMEM; + + fedata->irq = -1; + err = xenbus_scanf(XBT_NIL, dev->otherend, "port", "%u", + &evtchn); + if (err != 1) { + err = -EINVAL; + xenbus_dev_fatal(dev, err, "reading %s/event-channel", + dev->otherend); + goto error; + } + + err = xenbus_scanf(XBT_NIL, dev->otherend, "ring-ref", "%u", &ring_ref); + if (err != 1) { + err = -EINVAL; + xenbus_dev_fatal(dev, err, "reading %s/ring-ref", + dev->otherend); + goto error; + } + + err = bind_interdomain_evtchn_to_irq(dev->otherend_id, evtchn); + if (err < 0) + goto error; + fedata->irq = err; + + err = request_threaded_irq(fedata->irq, NULL, pvcalls_back_event, + IRQF_ONESHOT, "pvcalls-back", dev); + if (err < 0) + goto error; + + err = xenbus_map_ring_valloc(dev, &ring_ref, 1, + (void **)&fedata->sring); + if (err < 0) + goto error; + + BACK_RING_INIT(&fedata->ring, fedata->sring, XEN_PAGE_SIZE * 1); + fedata->dev = dev; + + INIT_LIST_HEAD(&fedata->socket_mappings); + INIT_RADIX_TREE(&fedata->socketpass_mappings, GFP_KERNEL); + sema_init(&fedata->socket_lock, 1); + dev_set_drvdata(&dev->dev, fedata); + + down(&pvcalls_back_global.frontends_lock); + list_add_tail(&fedata->list, &pvcalls_back_global.frontends); + up(&pvcalls_back_global.frontends_lock); + return 0; + + error: + if (fedata->irq >= 0) + unbind_from_irqhandler(fedata->irq, dev); + if (fedata->sring != NULL) + xenbus_unmap_ring_vfree(dev, fedata->sring); + kfree(fedata); + return err; } static int backend_disconnect(struct xenbus_device *dev)