diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/xen/xenbus/xenbus_probe_frontend.c | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/drivers/xen/xenbus/xenbus_probe_frontend.c b/drivers/xen/xenbus/xenbus_probe_frontend.c index 3159a37d966d..a7e25073de19 100644 --- a/drivers/xen/xenbus/xenbus_probe_frontend.c +++ b/drivers/xen/xenbus/xenbus_probe_frontend.c @@ -29,6 +29,8 @@ #include "xenbus_probe.h" +static struct workqueue_struct *xenbus_frontend_wq; + /* device/<type>/<id> => <type>-<id> */ static int frontend_bus_id(char bus_id[XEN_BUS_ID_SIZE], const char *nodename) { @@ -89,9 +91,40 @@ static void backend_changed(struct xenbus_watch *watch, xenbus_otherend_changed(watch, vec, len, 1); } +static void xenbus_frontend_delayed_resume(struct work_struct *w) +{ + struct xenbus_device *xdev = container_of(w, struct xenbus_device, work); + + xenbus_dev_resume(&xdev->dev); +} + +static int xenbus_frontend_dev_resume(struct device *dev) +{ + /* + * If xenstored is running in this domain, we cannot access the backend + * state at the moment, so we need to defer xenbus_dev_resume + */ + if (xen_store_domain_type == XS_LOCAL) { + struct xenbus_device *xdev = to_xenbus_device(dev); + + if (!xenbus_frontend_wq) { + pr_err("%s: no workqueue to process delayed resume\n", + xdev->nodename); + return -EFAULT; + } + + INIT_WORK(&xdev->work, xenbus_frontend_delayed_resume); + queue_work(xenbus_frontend_wq, &xdev->work); + + return 0; + } + + return xenbus_dev_resume(dev); +} + static const struct dev_pm_ops xenbus_pm_ops = { .suspend = xenbus_dev_suspend, - .resume = xenbus_dev_resume, + .resume = xenbus_frontend_dev_resume, .freeze = xenbus_dev_suspend, .thaw = xenbus_dev_cancel, .restore = xenbus_dev_resume, @@ -440,6 +473,8 @@ static int __init xenbus_probe_frontend_init(void) register_xenstore_notifier(&xenstore_notifier); + xenbus_frontend_wq = create_workqueue("xenbus_frontend"); + return 0; } subsys_initcall(xenbus_probe_frontend_init); |