Date: September. 2017
KernelVersion: 4.14
Contact: Stephen Hemminger <sthemmin@microsoft.com>
-Description: Channel signaling latency
+Description: Channel signaling latency. This file is available only for
+ performance critical channels (storage, network, etc.) that use
+ the monitor page mechanism.
Users: Debugging tools
What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/out_mask
Date: September. 2017
KernelVersion: 4.14
Contact: Stephen Hemminger <sthemmin@microsoft.com>
-Description: Channel interrupt pending state
+Description: Channel interrupt pending state. This file is available only for
+ performance critical channels (storage, network, etc.) that use
+ the monitor page mechanism.
Users: Debugging tools
What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/read_avail
Date: January. 2018
KernelVersion: 4.16
Contact: Stephen Hemminger <sthemmin@microsoft.com>
-Description: Monitor bit associated with channel
+Description: Monitor bit associated with channel. This file is available only
+ for performance critical channels (storage, network, etc.) that
+ use the monitor page mechanism.
Users: Debugging tools and userspace drivers
What: /sys/bus/vmbus/devices/<UUID>/channels/<N>/ring
&dev_attr_driver_override.attr,
NULL,
};
-ATTRIBUTE_GROUPS(vmbus_dev);
+
+/*
+ * Device-level attribute_group callback function. Returns the permission for
+ * each attribute, and returns 0 if an attribute is not visible.
+ */
+static umode_t vmbus_dev_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr, int idx)
+{
+ struct device *dev = kobj_to_dev(kobj);
+ const struct hv_device *hv_dev = device_to_hv_device(dev);
+
+ /* Hide the monitor attributes if the monitor mechanism is not used. */
+ if (!hv_dev->channel->offermsg.monitor_allocated &&
+ (attr == &dev_attr_monitor_id.attr ||
+ attr == &dev_attr_server_monitor_pending.attr ||
+ attr == &dev_attr_client_monitor_pending.attr ||
+ attr == &dev_attr_server_monitor_latency.attr ||
+ attr == &dev_attr_client_monitor_latency.attr ||
+ attr == &dev_attr_server_monitor_conn_id.attr ||
+ attr == &dev_attr_client_monitor_conn_id.attr))
+ return 0;
+
+ return attr->mode;
+}
+
+static const struct attribute_group vmbus_dev_group = {
+ .attrs = vmbus_dev_attrs,
+ .is_visible = vmbus_dev_attr_is_visible
+};
+__ATTRIBUTE_GROUPS(vmbus_dev);
/*
* vmbus_uevent - add uevent for our device
NULL
};
+/*
+ * Channel-level attribute_group callback function. Returns the permission for
+ * each attribute, and returns 0 if an attribute is not visible.
+ */
+static umode_t vmbus_chan_attr_is_visible(struct kobject *kobj,
+ struct attribute *attr, int idx)
+{
+ const struct vmbus_channel *channel =
+ container_of(kobj, struct vmbus_channel, kobj);
+
+ /* Hide the monitor attributes if the monitor mechanism is not used. */
+ if (!channel->offermsg.monitor_allocated &&
+ (attr == &chan_attr_pending.attr ||
+ attr == &chan_attr_latency.attr ||
+ attr == &chan_attr_monitor_id.attr))
+ return 0;
+
+ return attr->mode;
+}
+
+static struct attribute_group vmbus_chan_group = {
+ .attrs = vmbus_chan_attrs,
+ .is_visible = vmbus_chan_attr_is_visible
+};
+
static struct kobj_type vmbus_chan_ktype = {
.sysfs_ops = &vmbus_chan_sysfs_ops,
.release = vmbus_chan_release,
- .default_attrs = vmbus_chan_attrs,
};
/*
*/
int vmbus_add_channel_kobj(struct hv_device *dev, struct vmbus_channel *channel)
{
+ const struct device *device = &dev->device;
struct kobject *kobj = &channel->kobj;
u32 relid = channel->offermsg.child_relid;
int ret;
if (ret)
return ret;
+ ret = sysfs_create_group(kobj, &vmbus_chan_group);
+
+ if (ret) {
+ /*
+ * The calling functions' error handling paths will cleanup the
+ * empty channel directory.
+ */
+ dev_err(device, "Unable to set up channel sysfs files\n");
+ return ret;
+ }
+
kobject_uevent(kobj, KOBJ_ADD);
return 0;
}
+/*
+ * vmbus_remove_channel_attr_group - remove the channel's attribute group
+ */
+void vmbus_remove_channel_attr_group(struct vmbus_channel *channel)
+{
+ sysfs_remove_group(&channel->kobj, &vmbus_chan_group);
+}
+
/*
* vmbus_device_create - Creates and registers a new child device
* on the vmbus.