From d0e4d560c2433d29d11219567958b12bfe596d22 Mon Sep 17 00:00:00 2001 From: Stefano Stabellini Date: Thu, 6 Jul 2017 10:59:29 -0700 Subject: xen/pvcalls: connect to a frontend Introduce a per-frontend data structure named pvcalls_fedata. It contains pointers to the command ring, its event channel, a list of active sockets and a tree of passive sockets (passing sockets need to be looked up from the id on listen, accept and poll commands, while active sockets only on release). It also has an unbound workqueue to schedule the work of parsing and executing commands on the command ring. socket_lock protects the two lists. In pvcalls_back_global, keep a list of connected frontends. [ boris: fixed whitespaces/long lines ] Signed-off-by: Stefano Stabellini Reviewed-by: Boris Ostrovsky Reviewed-by: Juergen Gross CC: boris.ostrovsky@oracle.com CC: jgross@suse.com Signed-off-by: Boris Ostrovsky --- drivers/xen/pvcalls-back.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 82 insertions(+) (limited to 'drivers/xen') 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) -- cgit v1.2.3