lkml.org 
[lkml]   [2017]   [Jul]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v6 05/18] xen/pvcalls: connect to a frontend
From
Date
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 <stefano@aporeto.com>
> Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
> 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

\
 
 \ /
  Last update: 2017-07-04 08:59    [W:0.177 / U:2.832 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site