1:16 p.m.
On 04/14/2015 12:59 PM, Michal Privoznik wrote:
This is practically a wrapper over
"This is a simple wrapper around"
virNetDevBandwidthManipulateFilter() that will update the desired
filter on an interface (usually a network bridge) with a new MAC
address. Although, the MAC address in question usually refers to
some other interface - the one that the filter is constructed
for. Yeah, hard to parse. Thing is, our NATed network has a
Again with the extra unnecessary verbiage :-)
bridge where some part of QoS takes place. And vNICs from guests
are plugged into the bridge. However, if a guest decides to
change the MAC of its vNIC, corresponding qemu process emits an
s/corresponding/the corresponding/
event to which we respond somehow.
"... an event which we can use to update the QoS configuration based on
the new MAC address."
However, our QoS hierarchy is
currently not notified, therefore it falls apart.
"falls apart" is a bit lacking on the details :-)
This function
(when called from the correct place)
(when called in response to the aforementioned event)
will update our QoS
hierarchy and duck tape it together again.
Technically, it's "duct" tape (although there is one company that
capitalizes on the mispronunciation by calling theirs "Duck(tm) Tape".
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
src/libvirt_private.syms | 1 +
src/util/virnetdevbandwidth.c | 38 ++++++++++++++++++++++++++++++++++++++
src/util/virnetdevbandwidth.h | 6 ++++++
3 files changed, 45 insertions(+)
diff --git a/src/libvirt_private.syms b/src/libvirt_private.syms
index 7166283..547a919 100644
--- a/src/libvirt_private.syms
+++ b/src/libvirt_private.syms
@@ -1753,6 +1753,7 @@ virNetDevBandwidthFree;
virNetDevBandwidthPlug;
virNetDevBandwidthSet;
virNetDevBandwidthUnplug;
+virNetDevBandwidthUpdateFilter;
virNetDevBandwidthUpdateRate;
diff --git a/src/util/virnetdevbandwidth.c b/src/util/virnetdevbandwidth.c
index c57c8c0..0c49b41 100644
--- a/src/util/virnetdevbandwidth.c
+++ b/src/util/virnetdevbandwidth.c
@@ -680,3 +680,41 @@ virNetDevBandwidthUpdateRate(const char *ifname,
VIR_FREE(ceil);
return ret;
}
+
+/**
+ * virNetDevBandwidthUpdateFilter:
+ * @ifname: interface to operate on
+ * @ifmac_ptr: new MAC to update the filter with
+ * @id: filter ID
+ *
+ * Sometimes the host environment is so dynamic, that even
+ * guest's MAC addresses change on the fly. That's when we must
s/guest's/a guest's/
s/That's when/When that happens/
+ * update our QoS hierarchy so that guest's traffic is placed
s/guest's/the guest's/
+ * into correct QDiscs.
s/correct/the correct/
This function does exactly that. On the
+ * interface @ifname (usually a bridge) updates filter with
+ * unique identifier @id so that it reflects fact, that new
+ * address corresponding to the filter has changed to @ifmac_ptr.
This function updates the filter for the interface @ifname with the
unique identifier @id so that it uses the new MAC address of the guest
interface @ifmac_ptr.
+ *
+ * Returns: 0 on success,
+ * -1 on failure (with error reported).
+ */
+int
+virNetDevBandwidthUpdateFilter(const char *ifname,
+ const virMacAddr *ifmac_ptr,
+ unsigned int id)
+{
+ int ret = -1;
+ char *class_id = NULL;
+
+ if (virAsprintf(&class_id, "1:%x", id) < 0)
+ goto cleanup;
+
+ if (virNetDevBandwidthManipulateFilter(ifname, ifmac_ptr, id,
+ class_id, true, true) < 0)
+ goto cleanup;
+
+ ret = 0;
+ cleanup:
+ VIR_FREE(class_id);
+ return ret;
+}
diff --git a/src/util/virnetdevbandwidth.h b/src/util/virnetdevbandwidth.h
index efcf95a..9b1d2a6 100644
--- a/src/util/virnetdevbandwidth.h
+++ b/src/util/virnetdevbandwidth.h
@@ -73,4 +73,10 @@ int virNetDevBandwidthUpdateRate(const char *ifname,
unsigned long long new_rate)
ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2)
ATTRIBUTE_RETURN_CHECK;
+
+int virNetDevBandwidthUpdateFilter(const char *ifname,
+ const virMacAddr *ifmac_ptr,
+ unsigned int id)
+ ATTRIBUTE_NONNULL(1) ATTRIBUTE_NONNULL(2)
+ ATTRIBUTE_RETURN_CHECK;
#endif /* __VIR_NETDEV_BANDWIDTH_H__ */
ACK with the description cleaned up a bit.