BVI Interface

a new dedicated BVI interface as opposed to [re]using a loopback.

benefits:
 - removes ambiguity over the purpose of a loopback interface
 - TX node dedicated to BVI only functions.

Change-Id: I749d6b38440d450ac5b909a28053c75ec9df946a
Signed-off-by: Neale Ranns <nranns@cisco.com>

5 files changed, 505 insertions, 1 deletions

diff --git a/src/vnet/l2/l2.api b/src/vnet/l2/l2.api
index fc851e4203d..dc743763f70 100644
--- a/src/vnet/l2/l2.api
+++ b/src/vnet/l2/l2.api
@@ -553,6 +553,44 @@ autoreply define sw_interface_set_vpath
   u8 enable;
 };
 
+/** \brief Create BVI interface instance request
+    @param client_index - opaque cookie to identify the sender
+    @param context - sender context, to match reply w/ request
+    @param mac_address - mac addr to assign to the interface if none-zero
+    @param user_instance - requested instance, ~0 => dynamically allocate
+*/
+define bvi_create
+{
+  u32 client_index;
+  u32 context;
+  vl_api_mac_address_t mac;
+  u32 user_instance;
+};
+
+/** \brief Create BVI interface instance response
+    @param context - sender context, to match reply w/ request
+    @param sw_if_index - sw index of the interface that was created
+    @param retval - return code for the request
+*/
+define bvi_create_reply
+{
+  u32 context;
+  i32 retval;
+  u32 sw_if_index;
+};
+
+/** \brief Delete BVI interface request
+    @param client_index - opaque cookie to identify the sender
+    @param context - sender context, to match reply w/ request
+    @param sw_if_index - sw index of the interface that was created
+*/
+autoreply define bvi_delete
+{
+  u32 client_index;
+  u32 context;
+  u32 sw_if_index;
+};
+
 /*
  * Local Variables:
  * eval: (c-set-style "gnu")
diff --git a/src/vnet/l2/l2_api.c b/src/vnet/l2/l2_api.c
index 059f668d664..f60cd41bb39 100644
--- a/src/vnet/l2/l2_api.c
+++ b/src/vnet/l2/l2_api.c
@@ -27,6 +27,7 @@
 #include <vnet/l2/l2_vtr.h>
 #include <vnet/l2/l2_learn.h>
 #include <vnet/l2/l2_bd.h>
+#include <vnet/l2/l2_bvi.h>
 #include <vnet/ip/ip_types_api.h>
 #include <vnet/ethernet/ethernet_types_api.h>
 
@@ -74,7 +75,9 @@ _(BRIDGE_FLAGS, bridge_flags)                                   \
 _(L2_INTERFACE_VLAN_TAG_REWRITE, l2_interface_vlan_tag_rewrite) \
 _(L2_INTERFACE_PBB_TAG_REWRITE, l2_interface_pbb_tag_rewrite)   \
 _(BRIDGE_DOMAIN_SET_MAC_AGE, bridge_domain_set_mac_age)         \
-_(SW_INTERFACE_SET_VPATH, sw_interface_set_vpath)
+_(SW_INTERFACE_SET_VPATH, sw_interface_set_vpath)               \
+_(BVI_CREATE, bvi_create)                                       \
+_(BVI_DELETE, bvi_delete)
 
 static void
 send_l2_xconnect_details (vl_api_registration_t * reg, u32 context,
@@ -993,6 +996,37 @@ vl_api_sw_interface_set_vpath_t_handler (vl_api_sw_interface_set_vpath_t * mp)
   REPLY_MACRO (VL_API_SW_INTERFACE_SET_VPATH_REPLY);
 }
 
+static void
+vl_api_bvi_create_t_handler (vl_api_bvi_create_t * mp)
+{
+  vl_api_bvi_create_reply_t *rmp;
+  mac_address_t mac;
+  u32 sw_if_index;
+  int rv;
+
+  mac_address_decode (mp->mac, &mac);
+
+  rv = l2_bvi_create (ntohl (mp->user_instance), &mac, &sw_if_index);
+
+  /* *INDENT-OFF* */
+  REPLY_MACRO2(VL_API_BVI_CREATE_REPLY,
+  ({
+    rmp->sw_if_index = ntohl (sw_if_index);
+  }));
+  /* *INDENT-ON* */
+}
+
+static void
+vl_api_bvi_delete_t_handler (vl_api_bvi_delete_t * mp)
+{
+  vl_api_bvi_delete_reply_t *rmp;
+  int rv;
+
+  rv = l2_bvi_delete (ntohl (mp->sw_if_index));
+
+  REPLY_MACRO (VL_API_BVI_DELETE_REPLY);
+}
+
 /*
  * l2_api_hookup
  * Add vpe's API message handlers to the table.
diff --git a/src/vnet/l2/l2_bvi.c b/src/vnet/l2/l2_bvi.c
index f239743a9c4..87738fc7820 100644
--- a/src/vnet/l2/l2_bvi.c
+++ b/src/vnet/l2/l2_bvi.c
@@ -21,6 +21,8 @@
 #include <vnet/l2/l2_flood.h>
 #include <vnet/l2/l2_bvi.h>
 
+/* Allocated BVI instances */
+static uword *l2_bvi_instances;
 
 /* Call the L2 nodes that need the ethertype mapping */
 void
@@ -31,6 +33,315 @@ l2bvi_register_input_type (vlib_main_t * vm,
   l2flood_register_input_type (vm, type, node_index);
 }
 
+static u8 *
+format_bvi_name (u8 * s, va_list * args)
+{
+  u32 dev_instance = va_arg (*args, u32);
+  return format (s, "bvi%d", dev_instance);
+}
+
+static clib_error_t *
+bvi_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
+{
+  u32 hw_flags = (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP) ?
+    VNET_HW_INTERFACE_FLAG_LINK_UP : 0;
+  vnet_hw_interface_set_flags (vnm, hw_if_index, hw_flags);
+  return 0;
+}
+
+static clib_error_t *
+bvi_mac_change (vnet_hw_interface_t * hi,
+		const u8 * old_address, const u8 * mac_address)
+{
+  l2input_interface_mac_change (hi->sw_if_index, old_address, mac_address);
+
+  return (NULL);
+}
+
+/* *INDENT-OFF* */
+VNET_DEVICE_CLASS (bvi_device_class) = {
+  .name = "BVI",
+  .format_device_name = format_bvi_name,
+  .admin_up_down_function = bvi_admin_up_down,
+  .mac_addr_change_function = bvi_mac_change,
+};
+/* *INDENT-ON* */
+
+/*
+ * Maintain a bitmap of allocated bvi instance numbers.
+ */
+#define BVI_MAX_INSTANCE		(16 * 1024)
+
+static u32
+bvi_instance_alloc (u32 want)
+{
+  /*
+   * Check for dynamically allocaetd instance number.
+   */
+  if (~0 == want)
+    {
+      u32 bit;
+
+      bit = clib_bitmap_first_clear (l2_bvi_instances);
+      if (bit >= BVI_MAX_INSTANCE)
+	{
+	  return ~0;
+	}
+      l2_bvi_instances = clib_bitmap_set (l2_bvi_instances, bit, 1);
+      return bit;
+    }
+
+  /*
+   * In range?
+   */
+  if (want >= BVI_MAX_INSTANCE)
+    {
+      return ~0;
+    }
+
+  /*
+   * Already in use?
+   */
+  if (clib_bitmap_get (l2_bvi_instances, want))
+    {
+      return ~0;
+    }
+
+  /*
+   * Grant allocation request.
+   */
+  l2_bvi_instances = clib_bitmap_set (l2_bvi_instances, want, 1);
+
+  return want;
+}
+
+static int
+bvi_instance_free (u32 instance)
+{
+  if (instance >= BVI_MAX_INSTANCE)
+    {
+      return -1;
+    }
+
+  if (clib_bitmap_get (l2_bvi_instances, instance) == 0)
+    {
+      return -1;
+    }
+
+  l2_bvi_instances = clib_bitmap_set (l2_bvi_instances, instance, 0);
+  return 0;
+}
+
+int
+l2_bvi_create (u32 user_instance,
+	       const mac_address_t * mac_in, u32 * sw_if_indexp)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+  vlib_main_t *vm = vlib_get_main ();
+  u32 instance, hw_if_index, slot;
+  vnet_hw_interface_t *hw_if;
+  clib_error_t *error;
+  mac_address_t mac;
+
+  int rv = 0;
+
+  ASSERT (sw_if_indexp);
+
+  *sw_if_indexp = (u32) ~ 0;
+
+  /*
+   * Allocate a bvi instance.  Either select on dynamically
+   * or try to use the desired user_instance number.
+   */
+  instance = bvi_instance_alloc (user_instance);
+  if (instance == ~0)
+    {
+      return VNET_API_ERROR_INVALID_REGISTRATION;
+    }
+
+  /*
+   * Default MAC address (b0b0:0000:0000 + instance) is allocated
+   * if zero mac_address is configured. Otherwise, user-configurable MAC
+   * address is programmed on the bvi interface.
+   */
+  if (mac_address_is_zero (mac_in))
+    {
+      u8 bytes[] = {
+	[0] = 0xb0,
+	[1] = 0xb0,
+	[5] = instance,
+      };
+      mac_address_from_bytes (&mac, bytes);
+    }
+  else
+    {
+      mac_address_copy (&mac, mac_in);
+    }
+
+  error = ethernet_register_interface (vnm,
+				       bvi_device_class.index,
+				       instance, mac.bytes, &hw_if_index,
+				       /* flag change */ 0);
+
+  if (error)
+    {
+      rv = VNET_API_ERROR_INVALID_REGISTRATION;
+      clib_error_report (error);
+      return rv;
+    }
+
+  hw_if = vnet_get_hw_interface (vnm, hw_if_index);
+
+  slot = vlib_node_add_named_next_with_slot (vm, hw_if->tx_node_index,
+					     "l2-input", 0);
+  ASSERT (slot == 0);
+
+  {
+    vnet_sw_interface_t *si = vnet_get_hw_sw_interface (vnm, hw_if_index);
+    *sw_if_indexp = si->sw_if_index;
+
+    si->flood_class = VNET_FLOOD_CLASS_BVI;
+  }
+
+  return 0;
+}
+
+int
+l2_bvi_delete (u32 sw_if_index)
+{
+  vnet_main_t *vnm = vnet_get_main ();
+
+  if (pool_is_free_index (vnm->interface_main.sw_interfaces, sw_if_index))
+    return VNET_API_ERROR_INVALID_SW_IF_INDEX;
+
+  vnet_hw_interface_t *hw = vnet_get_sup_hw_interface (vnm, sw_if_index);
+  if (hw == 0 || hw->dev_class_index != bvi_device_class.index)
+    return VNET_API_ERROR_INVALID_SW_IF_INDEX;
+
+  if (bvi_instance_free (hw->dev_instance) < 0)
+    return VNET_API_ERROR_INVALID_SW_IF_INDEX;
+
+  ethernet_delete_interface (vnm, hw->hw_if_index);
+
+  return 0;
+}
+
+static clib_error_t *
+l2_bvi_create_cli (vlib_main_t * vm,
+		   unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  unformat_input_t _line_input, *line_input = &_line_input;
+  u32 instance, sw_if_index;
+  clib_error_t *error;
+  mac_address_t mac;
+  int rv;
+
+  error = NULL;
+  instance = sw_if_index = ~0;
+  mac_address_set_zero (&mac);
+
+  if (unformat_user (input, unformat_line_input, line_input))
+    {
+      while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+	{
+	  if (unformat (line_input, "mac %U", unformat_mac_address_t, &mac))
+	    ;
+	  else if (unformat (line_input, "instance %d", &instance))
+	    ;
+	  else
+	    {
+	      error = clib_error_return (0, "unknown input: %U",
+					 format_unformat_error, line_input);
+	      break;
+	    }
+	}
+
+      unformat_free (line_input);
+
+      if (error)
+	return error;
+    }
+
+  rv = l2_bvi_create (instance, &mac, &sw_if_index);
+
+  if (rv)
+    return clib_error_return (0, "BVI create failed");
+
+  vlib_cli_output (vm, "%U\n", format_vnet_sw_if_index_name, vnet_get_main (),
+		   sw_if_index);
+  return 0;
+}
+
+/*?
+ * Create a BVI interface. Optionally, a MAC Address can be
+ * provided. If not provided, 0b:0b::00:00:00:<instance> will be used.
+ *
+ * @cliexpar
+ * The following two command syntaxes are equivalent:
+ * @cliexcmd{bvi create [mac <mac-addr>] [instance <instance>]}
+ * Example of how to create a bvi interface:
+ * @cliexcmd{bvi create}
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_bvi_create_command, static) = {
+  .path = "bvi create",
+  .short_help = "bvi create [mac <mac-addr>] [instance <instance>]",
+  .function = l2_bvi_create_cli,
+};
+/* *INDENT-ON* */
+
+static clib_error_t *
+l2_bvi_delete_cli (vlib_main_t * vm,
+		   unformat_input_t * input, vlib_cli_command_t * cmd)
+{
+  vnet_main_t *vnm;
+  u32 sw_if_index;
+  int rv;
+
+  vnm = vnet_get_main ();
+  sw_if_index = ~0;
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat
+	  (input, "%U", unformat_vnet_sw_interface, vnm, &sw_if_index))
+	;
+      else
+	break;
+    }
+
+  if (~0 != sw_if_index)
+    {
+      rv = l2_bvi_delete (sw_if_index);
+
+      if (rv)
+	return clib_error_return (0, "BVI delete failed");
+    }
+  else
+    return clib_error_return (0, "no such interface: %U",
+			      format_unformat_error, input);
+
+  return 0;
+}
+
+/*?
+ * Delete a BVI interface.
+ *
+ * @cliexpar
+ * The following two command syntaxes are equivalent:
+ * @cliexcmd{bvi delete <interace>
+ * Example of how to create a bvi interface:
+ * @cliexcmd{bvi delete bvi0}
+?*/
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (l2_bvi_delete_command, static) = {
+  .path = "bvi delete",
+  .short_help = "bvi delete <interface>",
+  .function = l2_bvi_delete_cli,
+};
+/* *INDENT-ON* */
+
+
 /*
  * fd.io coding-style-patch-verification: ON
  *
diff --git a/src/vnet/l2/l2_bvi.h b/src/vnet/l2/l2_bvi.h
index 51c8dac23e4..d7d410b06ab 100644
--- a/src/vnet/l2/l2_bvi.h
+++ b/src/vnet/l2/l2_bvi.h
@@ -97,6 +97,11 @@ l2_to_bvi (vlib_main_t * vlib_main,
 void
 l2bvi_register_input_type (vlib_main_t * vm,
 			   ethernet_type_t type, u32 node_index);
+
+extern int l2_bvi_create (u32 instance, const mac_address_t * mac,
+			  u32 * sw_if_index);
+extern int l2_bvi_delete (u32 sw_if_index);
+
 #endif
 
 /*
diff --git a/src/vnet/l2/l2_bvi_node.c b/src/vnet/l2/l2_bvi_node.c
new file mode 100644
index 00000000000..dd7e1df46ce
--- /dev/null
+++ b/src/vnet/l2/l2_bvi_node.c
@@ -0,0 +1,116 @@
+/*
+ * l2_bvi.c : layer 2 Bridged Virtual Interface
+ *
+ * Copyright (c) 2013 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <vnet/l2/l2_bvi.h>
+
+/**
+ * send packets to l2-input.
+ */
+VNET_DEVICE_CLASS_TX_FN (bvi_device_class) (vlib_main_t * vm,
+					    vlib_node_runtime_t * node,
+					    vlib_frame_t * frame)
+{
+  u32 sw_if_indices[VLIB_FRAME_SIZE], *sw_if_index;
+  vlib_buffer_t *bufs[VLIB_FRAME_SIZE], **b;
+  u16 nexts[VLIB_FRAME_SIZE];
+  u32 n_left, *from;
+
+  n_left = frame->n_vectors;
+  from = vlib_frame_vector_args (frame);
+
+  vlib_get_buffers (vm, from, bufs, n_left);
+
+  b = bufs;
+  sw_if_index = sw_if_indices;
+
+  /* It's all going to l2-input */
+  clib_memset_u16 (nexts, 0, VLIB_FRAME_SIZE);
+
+  /*
+   * For each packet:
+   *  - fixup the L2 length of the packet
+   *  - set the RX interface (which the bridge will use) to the
+   *    TX interface (which routing has chosen)
+   *  - Set the TX interface to the special ID so the DP knows this is a BVI
+   * Don't counts packets and bytes, that's done in the bviX-output node
+   */
+  while (n_left >= 4)
+    {
+      /* Prefetch next iteration. */
+      if (PREDICT_TRUE (n_left >= 8))
+	{
+	  /* LOAD pre-fetch since meta and packet data is read */
+	  vlib_prefetch_buffer_header (b[4], LOAD);
+	  vlib_prefetch_buffer_header (b[5], LOAD);
+	  vlib_prefetch_buffer_header (b[6], LOAD);
+	  vlib_prefetch_buffer_header (b[7], LOAD);
+
+	  vlib_prefetch_buffer_data (b[4], LOAD);
+	  vlib_prefetch_buffer_data (b[5], LOAD);
+	  vlib_prefetch_buffer_data (b[6], LOAD);
+	  vlib_prefetch_buffer_data (b[7], LOAD);
+	}
+
+      vnet_update_l2_len (b[0]);
+      vnet_update_l2_len (b[1]);
+      vnet_update_l2_len (b[2]);
+      vnet_update_l2_len (b[3]);
+
+      sw_if_index[0] = vnet_buffer (b[0])->sw_if_index[VLIB_TX];
+      sw_if_index[1] = vnet_buffer (b[1])->sw_if_index[VLIB_TX];
+      sw_if_index[2] = vnet_buffer (b[2])->sw_if_index[VLIB_TX];
+      sw_if_index[3] = vnet_buffer (b[3])->sw_if_index[VLIB_TX];
+
+      vnet_buffer (b[0])->sw_if_index[VLIB_TX] = L2INPUT_BVI;
+      vnet_buffer (b[1])->sw_if_index[VLIB_TX] = L2INPUT_BVI;
+      vnet_buffer (b[2])->sw_if_index[VLIB_TX] = L2INPUT_BVI;
+      vnet_buffer (b[3])->sw_if_index[VLIB_TX] = L2INPUT_BVI;
+
+      vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index[0];
+      vnet_buffer (b[1])->sw_if_index[VLIB_RX] = sw_if_index[1];
+      vnet_buffer (b[2])->sw_if_index[VLIB_RX] = sw_if_index[2];
+      vnet_buffer (b[3])->sw_if_index[VLIB_RX] = sw_if_index[3];
+
+      b += 4;
+      n_left -= 4;
+      sw_if_index += 4;
+    }
+  while (n_left)
+    {
+      sw_if_index[0] = vnet_buffer (b[0])->sw_if_index[VLIB_TX];
+      vnet_buffer (b[0])->sw_if_index[VLIB_TX] = L2INPUT_BVI;
+      vnet_buffer (b[0])->sw_if_index[VLIB_RX] = sw_if_index[0];
+
+      vnet_update_l2_len (b[0]);
+
+      b += 1;
+      n_left -= 1;
+      sw_if_index += 1;
+    }
+
+  vlib_buffer_enqueue_to_next (vm, node, from, nexts, frame->n_vectors);
+
+  return frame->n_vectors;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */