From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752341AbdGDG7N (ORCPT ); Tue, 4 Jul 2017 02:59:13 -0400 Received: from mx2.suse.de ([195.135.220.15]:45587 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752169AbdGDG7M (ORCPT ); Tue, 4 Jul 2017 02:59:12 -0400 Subject: Re: [PATCH v6 05/18] xen/pvcalls: connect to a frontend To: Stefano Stabellini , xen-devel@lists.xen.org Cc: linux-kernel@vger.kernel.org, boris.ostrovsky@oracle.com, Stefano Stabellini References: <1499116119-15638-1-git-send-email-sstabellini@kernel.org> <1499116119-15638-5-git-send-email-sstabellini@kernel.org> From: Juergen Gross Message-ID: <9cd1f1d2-c37c-aabd-84c0-718da54ca7fd@suse.com> Date: Tue, 4 Jul 2017 08:59:09 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <1499116119-15638-5-git-send-email-sstabellini@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: de-DE Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/07/17 23:08, Stefano Stabellini wrote: > 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. > > Signed-off-by: Stefano Stabellini > Reviewed-by: Boris Ostrovsky > CC: boris.ostrovsky@oracle.com > CC: jgross@suse.com > --- > drivers/xen/pvcalls-back.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 92 insertions(+) > > diff --git a/drivers/xen/pvcalls-back.c b/drivers/xen/pvcalls-back.c > index 7bce750..e4c2e46 100644 > --- a/drivers/xen/pvcalls-back.c > +++ b/drivers/xen/pvcalls-back.c > @@ -33,9 +33,101 @@ 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; > + struct workqueue_struct *wq; > + struct work_struct register_work; > +}; > + > +static void pvcalls_back_work(struct work_struct *work) > +{ > +} > + > +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; > + > + 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_irqhandler(dev->otherend_id, evtchn, > + pvcalls_back_event, 0, > + "pvcalls-backend", dev); > + if (err < 0) > + goto error; > + fedata->irq = err; > + > + fedata->wq = alloc_workqueue("pvcalls_back_wq", WQ_UNBOUND, 1); > + if (!fedata->wq) { > + err = -ENOMEM; > + 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_WORK(&fedata->register_work, pvcalls_back_work); > + 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); > + queue_work(fedata->wq, &fedata->register_work); > + > return 0; > + > + error: > + if (fedata->sring != NULL) > + xenbus_unmap_ring_vfree(dev, fedata->sring); > + if (fedata->wq) > + destroy_workqueue(fedata->wq); > + unbind_from_irqhandler(fedata->irq, dev); fedata->irq might have not been set and can be zero here. irq 0 is a valid irq, I think. Juergen