Add support for API client to receive L2 MAC events

Added APIs want_l2_macs_events and l2_macs_event to allow an API
client to receive notification events from VPP for MAC learned
or aged in L2FIB. Only one API client is allowed for L2 MAC events.

The want_l2_macs_events API allow caller to specify MAC learn
limit, event scan delay and max number of MACs that can be included
in a event message. These parameters should be choosen properly as
to not have too many MAC events sent by VPP and overwhelm the API
share memory. They can all be left as 0's so VPP will setup reasonable
defaults which are: 1000 learn limit, 100 msec scan delay and 100
MACs per event message.

If want_l2_macs_events is never called, VPP learning and aging
should behave as before except that MAC entries provisioned by API
or CLI will not be aged, even if it is not set as static_mac. These
non static MACs, however, can be overwritten by MAC learning on a
MAC move as a leared MAC. Only learned MACs are subject to aging.

Change-Id: Ia3757a80cf8adb2811a089d2eafbd6439461285c
Signed-off-by: John Lo <loj@cisco.com>

1 files changed, 59 insertions, 6 deletions

diff --git a/src/vnet/l2/l2.api b/src/vnet/l2/l2.api
index bb3990c6fa4..e508bfb529c 100644
--- a/src/vnet/l2/l2.api
+++ b/src/vnet/l2/l2.api
@@ -133,12 +133,64 @@ autoreply define l2fib_add_del
   u8 bvi_mac;
 };
 
-/** \brief Set L2 flags request !!! TODO - need more info, feature bits in l2_input.h
+/** \brief Register to recive L2 MAC events for leanred and aged MAC
+    Will also change MAC learn limit to L2LEARN_INFORM_LIMIT
+    @param client_index - opaque cookie to identify the sender
+    @param context - sender context, to match reply w/ request
+    @param learn_limit - MAC learn limit, 0 => default to 1000
+    @param scan_delay - event scan delay in 10 msec unit, 0 => default to 100 msec
+    @param max_macs_in_event - in units of 10 mac entries, 0 => default to 100 entries
+    @param enable_disable - 1 => register for MAC events, 0 => cancel registration
+    @param pid - sender's pid
+*/
+autoreply define want_l2_macs_events
+{
+  u32 client_index;
+  u32 context;
+  u32 learn_limit;
+  u8  scan_delay;
+  u8  max_macs_in_event;
+  u8  enable_disable;
+  u32 pid;
+};
+
+/** \brief Entry for learned or aged MAC in L2 MAC Events
+    @param sw_if_index - sw_if_index in the domain
+    @param mac_addr - mac_address
+    @is_del - 0 => newly learned MAC, 1 => aged out MAC
+*/
+typeonly define mac_entry
+{
+  u32 sw_if_index;
+  u8  mac_addr[6];
+  u8  is_del;
+  u8  spare;
+};
+
+/** \brief L2 MAC event for a list of learned or aged MACs
+    @param client_index - opaque cookie to identify the sender
+    @param pid - client pid registered to receive notification
+    @param n_macs - number of learned/aged MAC enntries
+    @param mac - array of learned/aged MAC entries
+*/
+define l2_macs_event
+{
+  u32 client_index;
+  u32 pid;
+  u32 n_macs;
+  vl_api_mac_entry_t mac[n_macs];
+};
+
+/** \brief Set interface L2 flags (such as L2_LEARN, L2_FWD, 
+    L2_FLOOD, L2_UU_FLOOD, or L2_ARP_TERM bits). This can be used
+    to disable one or more of the features represented by the
+    flag bits on an interface to override what is set as default
+    for all interfaces in the bridge domain
     @param client_index - opaque cookie to identify the sender
     @param context - sender context, to match reply w/ request
     @param sw_if_index - interface 
     @param is_set - if non-zero, set the bits, else clear them
-    @param feature_bitmap - non-zero bits to set or clear
+    @param feature_bitmap - non-zero bits (as above) to set or clear
 */
 define l2_flags
 {
@@ -149,9 +201,10 @@ define l2_flags
   u32 feature_bitmap;
 };
 
-/** \brief Set L2 bits response
+/** \brief Set interface L2 flags response
     @param context - sender context, to match reply w/ request
     @param retval - return code for the set l2 bits request
+    @param resulting_feature_bitmap - the internal l2 feature bitmap after the request is implemented
 */
 define l2_flags_reply
 {
@@ -250,12 +303,12 @@ manual_print manual_endian define bridge_domain_details
 };
 
 /** \brief Set bridge flags (such as L2_LEARN, L2_FWD, L2_FLOOD, 
-    L2_UU_FLOOD, or L2_ARP_TERM) request
+    L2_UU_FLOOD, or L2_ARP_TERM bits) request
     @param client_index - opaque cookie to identify the sender
     @param context - sender context, to match reply w/ request
     @param bd_id - the bridge domain to set the flags for
     @param is_set - if non-zero, set the flags, else clear them
-    @param feature_bitmap - bits that are non-zero to set or clear
+    @param feature_bitmap - bits (as above) that are non-zero to set or clear
 */
 define bridge_flags
 {
@@ -269,7 +322,7 @@ define bridge_flags
 /** \brief Set bridge flags response
     @param context - sender context, to match reply w/ request
     @param retval - return code for the set bridge flags request
-    @param resulting_feature_bitmap - the feature bitmap value after the request is implemented
+    @param resulting_feature_bitmap - the internal L2 feature bitmap after the request is implemented
 */
 define bridge_flags_reply
 {