Add a 64-byte interface "tag" for vhost and tap interfaces

This patch should dispose of spurious objections around interface tag
requirements, currently in use as excuses not to support the vpp ML2
plugin.

Add "u8 tag[64];" to the sw_interface_details message sent by vpp to
control-plane clients. Add u8 tag[64] to the create_vhost_user_if and
tap_connect APIs.

Added debug CLI to set/show/clear the interface tag on any vnet sw
interface. Added the sw_interface_tag_add_del API to set/clear
tags on any vnet sw interface.

There can be no expectation of "tag atomicity" with respect to
physical hardware. Vpp discovers devices before establishing a
control-plane connection.

This patch upload verifies using the csit oper-161128 branch

Change-Id: If8520119e7a586c5ccf0fdda82484ac205622855
Signed-off-by: Dave Barach <dave@barachs.net>

1 files changed, 70 insertions, 4 deletions

diff --git a/vpp/vpp-api/api.c b/vpp/vpp-api/api.c
index 2c0256cc..b5253726 100644
--- a/vpp/vpp-api/api.c
+++ b/vpp/vpp-api/api.c
@@ -255,8 +255,8 @@ _(COP_INTERFACE_ENABLE_DISABLE, cop_interface_enable_disable)		\
 _(COP_WHITELIST_ENABLE_DISABLE, cop_whitelist_enable_disable)		\
 _(GET_NODE_GRAPH, get_node_graph)                                       \
 _(SW_INTERFACE_CLEAR_STATS, sw_interface_clear_stats)                   \
-_(IOAM_ENABLE, ioam_enable)                                 \
-_(IOAM_DISABLE, ioam_disable)                                 \
+_(IOAM_ENABLE, ioam_enable)                                             \
+_(IOAM_DISABLE, ioam_disable)                                           \
 _(LISP_ADD_DEL_LOCATOR_SET, lisp_add_del_locator_set)                   \
 _(LISP_ADD_DEL_LOCATOR, lisp_add_del_locator)                           \
 _(LISP_ADD_DEL_LOCAL_EID, lisp_add_del_local_eid)                       \
@@ -332,7 +332,8 @@ _(IP_FIB_DUMP, ip_fib_dump)                                             \
 _(IP_FIB_DETAILS, ip_fib_details)                                       \
 _(IP6_FIB_DUMP, ip6_fib_dump)                                           \
 _(IP6_FIB_DETAILS, ip6_fib_details)                                     \
-_(FEATURE_ENABLE_DISABLE, feature_enable_disable)
+_(FEATURE_ENABLE_DISABLE, feature_enable_disable)			\
+_(SW_INTERFACE_TAG_ADD_DEL, sw_interface_tag_add_del)
 
 #define QUOTE_(x) #x
 #define QUOTE(x) QUOTE_(x)
@@ -1997,8 +1998,10 @@ vl_api_tap_connect_t_handler (vl_api_tap_connect_t * mp, vlib_main_t * vm)
 {
   int rv;
   vl_api_tap_connect_reply_t *rmp;
+  vnet_main_t *vnm = vnet_get_main ();
   unix_shared_memory_queue_t *q;
   u32 sw_if_index = (u32) ~ 0;
+  u8 *tag;
 
   rv = vnet_tap_connect_renumber (vm, mp->tap_name,
 				  mp->use_random_mac ? 0 : mp->mac_address,
@@ -2009,6 +2012,14 @@ vl_api_tap_connect_t_handler (vl_api_tap_connect_t * mp, vlib_main_t * vm)
   if (!q)
     return;
 
+  /* Add tag if supplied */
+  if (rv == 0 && mp->tag[0])
+    {
+      mp->tag[ARRAY_LEN (mp->tag) - 1] = 0;
+      tag = format (0, "%s%c", mp->tag, 0);
+      vnet_set_sw_interface_tag (vnm, tag, sw_if_index);
+    }
+
   rmp = vl_msg_api_alloc (sizeof (*rmp));
   rmp->_vl_msg_id = ntohs (VL_API_TAP_CONNECT_REPLY);
   rmp->context = mp->context;
@@ -2054,6 +2065,11 @@ vl_api_tap_delete_t_handler (vl_api_tap_delete_t * mp, vlib_main_t * vm)
   u32 sw_if_index = ntohl (mp->sw_if_index);
 
   rv = vnet_tap_delete (vm, sw_if_index);
+  if (!rv)
+    {
+      vnet_main_t *vnm = vnet_get_main ();
+      vnet_clear_sw_interface_tag (vnm, sw_if_index);
+    }
 
   q = vl_api_client_index_to_input_queue (mp->client_index);
   if (!q)
@@ -2684,7 +2700,9 @@ send_sw_interface_details (vpe_api_main_t * am,
 			   u8 * interface_name, u32 context)
 {
   vl_api_sw_interface_details_t *mp;
+  vnet_main_t *vnm = vnet_get_main ();
   vnet_hw_interface_t *hi;
+  u8 *tag;
 
   hi = vnet_get_sup_hw_interface (am->vnet_main, swif->sw_if_index);
 
@@ -2752,6 +2770,10 @@ send_sw_interface_details (vpe_api_main_t * am,
 	}
     }
 
+  tag = vnet_get_sw_interface_tag (vnm, swif->sw_if_index);
+  if (tag)
+    strncpy ((char *) mp->tag, (char *) tag, ARRAY_LEN (mp->tag) - 1);
+
   vl_msg_api_send_shmem (q, (u8 *) & mp);
 }
 
@@ -4020,7 +4042,6 @@ vl_api_create_vhost_user_if_t_handler (vl_api_create_vhost_user_if_t * mp)
   int rv = 0;
   vl_api_create_vhost_user_if_reply_t *rmp;
   u32 sw_if_index = (u32) ~ 0;
-
   vnet_main_t *vnm = vnet_get_main ();
   vlib_main_t *vm = vlib_get_main ();
 
@@ -4029,6 +4050,19 @@ vl_api_create_vhost_user_if_t_handler (vl_api_create_vhost_user_if_t * mp)
 			     mp->renumber, ntohl (mp->custom_dev_instance),
 			     (mp->use_custom_mac) ? mp->mac_address : NULL);
 
+  /* Remember an interface tag for the new interface */
+  if (rv == 0)
+    {
+      /* If a tag was supplied... */
+      if (mp->tag[0])
+	{
+	  /* Make sure it's a proper C-string */
+	  mp->tag[ARRAY_LEN (mp->tag) - 1] = 0;
+	  u8 *tag = format (0, "%s%c", mp->tag, 0);
+	  vnet_set_sw_interface_tag (vnm, tag, sw_if_index);
+	}
+    }
+
   /* *INDENT-OFF* */
   REPLY_MACRO2(VL_API_CREATE_VHOST_USER_IF_REPLY,
   ({
@@ -4074,6 +4108,7 @@ vl_api_delete_vhost_user_if_t_handler (vl_api_delete_vhost_user_if_t * mp)
       if (!q)
 	return;
 
+      vnet_clear_sw_interface_tag (vnm, sw_if_index);
       send_sw_interface_flags_deleted (vam, q, sw_if_index);
     }
 }
@@ -9113,6 +9148,37 @@ vl_api_feature_enable_disable_t_handler (vl_api_feature_enable_disable_t * mp)
   REPLY_MACRO (VL_API_FEATURE_ENABLE_DISABLE_REPLY);
 }
 
+static void vl_api_sw_interface_tag_add_del_t_handler
+  (vl_api_sw_interface_tag_add_del_t * mp)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  vl_api_sw_interface_tag_add_del_reply_t *rmp;
+  int rv = 0;
+  u8 *tag;
+  u32 sw_if_index = ntohl (mp->sw_if_index);
+
+  VALIDATE_SW_IF_INDEX (mp);
+
+  if (mp->is_add)
+    {
+      if (mp->tag[0] == 0)
+	{
+	  rv = VNET_API_ERROR_INVALID_VALUE;
+	  goto out;
+	}
+
+      mp->tag[ARRAY_LEN (mp->tag) - 1] = 0;
+      tag = format (0, "%s%c", mp->tag, 0);
+      vnet_set_sw_interface_tag (vnm, tag, sw_if_index);
+    }
+  else
+    vnet_clear_sw_interface_tag (vnm, sw_if_index);
+
+  BAD_SW_IF_INDEX_LABEL;
+out:
+  REPLY_MACRO (VL_API_SW_INTERFACE_TAG_ADD_DEL_REPLY);
+}
+
 #define BOUNCE_HANDLER(nn)                                              \
 static void vl_api_##nn##_t_handler (                                   \
     vl_api_##nn##_t *mp)                                                \