dpdk: remove rte_mbuf modifications at many places in the code

It is sole responsibility of dpdk tx function to fill/update
rte_mbuf prior to sending packet do PMD.

Change-Id: I8ca1dba3e7bef41034d36e3525831849f7ac4ac0
Signed-off-by: Damjan Marion <damarion@cisco.com>

15 files changed, 7 insertions, 239 deletions

diff --git a/vnet/vnet/buffer.h b/vnet/vnet/buffer.h
index d3ad8644..2ae4f1cc 100644
--- a/vnet/vnet/buffer.h
+++ b/vnet/vnet/buffer.h
@@ -67,6 +67,9 @@
 #define LOG2_BUFFER_HANDOFF_NEXT_VALID LOG2_VLIB_BUFFER_FLAG_USER(6)
 #define BUFFER_HANDOFF_NEXT_VALID (1 << LOG2_BUFFER_HANDOFF_NEXT_VALID)
 
+#define LOG2_VNET_BUFFER_RTE_MBUF_IS_VALID LOG2_VLIB_BUFFER_FLAG_USER(7)
+#define VNET_BUFFER_RTE_MBUF_IS_VALID (1 << LOG2_VNET_BUFFER_RTE_MBUF_IS_VALID)
+
 #define foreach_buffer_opaque_union_subtype     \
 _(ethernet)                                     \
 _(ip)                                           \
diff --git a/vnet/vnet/devices/af_packet/node.c b/vnet/vnet/devices/af_packet/node.c
index 083c5581..72004320 100644
--- a/vnet/vnet/devices/af_packet/node.c
+++ b/vnet/vnet/devices/af_packet/node.c
@@ -104,17 +104,6 @@ buffer_add_to_chain (vlib_main_t * vm, u32 bi, u32 first_bi, u32 prev_bi)
 
   /* update current buffer */
   b->next_buffer = 0;
-
-#if DPDK > 0
-  struct rte_mbuf *mbuf = rte_mbuf_from_vlib_buffer (b);
-  struct rte_mbuf *first_mbuf = rte_mbuf_from_vlib_buffer (first_b);
-  struct rte_mbuf *prev_mbuf = rte_mbuf_from_vlib_buffer (prev_b);
-  first_mbuf->nb_segs++;
-  prev_mbuf->next = mbuf;
-  mbuf->data_len = b->current_length;
-  mbuf->data_off = RTE_PKTMBUF_HEADROOM + b->current_data;
-  mbuf->next = 0;
-#endif
 }
 
 always_inline uword
@@ -194,11 +183,6 @@ af_packet_device_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 
 	      if (offset == 0)
 		{
-#if DPDK > 0
-		  struct rte_mbuf *mb = rte_mbuf_from_vlib_buffer (b0);
-		  rte_pktmbuf_data_len (mb) = b0->current_length;
-		  rte_pktmbuf_pkt_len (mb) = b0->current_length;
-#endif
 		  b0->total_length_not_including_first_buffer = 0;
 		  b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
 		  vnet_buffer (b0)->sw_if_index[VLIB_RX] = apif->sw_if_index;
diff --git a/vnet/vnet/devices/netmap/node.c b/vnet/vnet/devices/netmap/node.c
index b96bada5..19895e47 100644
--- a/vnet/vnet/devices/netmap/node.c
+++ b/vnet/vnet/devices/netmap/node.c
@@ -83,17 +83,6 @@ buffer_add_to_chain (vlib_main_t * vm, u32 bi, u32 first_bi, u32 prev_bi)
 
   /* update current buffer */
   b->next_buffer = 0;
-
-#if DPDK > 0
-  struct rte_mbuf *mbuf = rte_mbuf_from_vlib_buffer (b);
-  struct rte_mbuf *first_mbuf = rte_mbuf_from_vlib_buffer (first_b);
-  struct rte_mbuf *prev_mbuf = rte_mbuf_from_vlib_buffer (prev_b);
-  first_mbuf->nb_segs++;
-  prev_mbuf->next = mbuf;
-  mbuf->data_len = b->current_length;
-  mbuf->data_off = RTE_PKTMBUF_HEADROOM + b->current_data;
-  mbuf->next = 0;
-#endif
 }
 
 always_inline uword
@@ -195,11 +184,6 @@ netmap_device_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
 
 		  if (offset == 0)
 		    {
-#if DPDK > 0
-		      struct rte_mbuf *mb = rte_mbuf_from_vlib_buffer (b0);
-		      rte_pktmbuf_data_len (mb) = b0->current_length;
-		      rte_pktmbuf_pkt_len (mb) = b0->current_length;
-#endif
 		      b0->total_length_not_including_first_buffer = 0;
 		      b0->flags = VLIB_BUFFER_TOTAL_LENGTH_VALID;
 		      vnet_buffer (b0)->sw_if_index[VLIB_RX] =
diff --git a/vnet/vnet/devices/ssvm/node.c b/vnet/vnet/devices/ssvm/node.c
index 5ecccd37..3a695b1d 100644
--- a/vnet/vnet/devices/ssvm/node.c
+++ b/vnet/vnet/devices/ssvm/node.c
@@ -77,11 +77,7 @@ ssvm_eth_device_input (ssvm_eth_main_t * em,
   int rx_queue_index;
   u32 n_to_alloc = VLIB_FRAME_SIZE * 2;
   u32 n_allocated, n_present_in_cache;
-#if DPDK > 0
   u32 next_index = VNET_DEVICE_INPUT_NEXT_ETHERNET_INPUT;
-#else
-  u32 next_index = 0;
-#endif
   vlib_buffer_free_list_t *fl;
   u32 n_left_to_next, *to_next;
   u32 next0;
diff --git a/vnet/vnet/devices/ssvm/ssvm_eth.h b/vnet/vnet/devices/ssvm/ssvm_eth.h
index f4156e3a..ac611f4e 100644
--- a/vnet/vnet/devices/ssvm/ssvm_eth.h
+++ b/vnet/vnet/devices/ssvm/ssvm_eth.h
@@ -25,6 +25,7 @@
 #include <vppinfra/elog.h>
 #include <vlib/vlib.h>
 #include <vnet/ethernet/ethernet.h>
+#include <vnet/devices/devices.h>
 #include <vnet/ip/ip.h>
 #include <vnet/pg/pg.h>
 #include <vlibmemory/unix_shared_memory_queue.h>
diff --git a/vnet/vnet/devices/virtio/vhost-user.h b/vnet/vnet/devices/virtio/vhost-user.h
index 0495991d..4ce08309 100644
--- a/vnet/vnet/devices/virtio/vhost-user.h
+++ b/vnet/vnet/devices/virtio/vhost-user.h
@@ -32,10 +32,6 @@
 #define VHOST_VRING_F_LOG 0
 
 #define VHOST_USER_F_PROTOCOL_FEATURES  30
-#if DPDK == 0
-#define RTE_VERSION_NUM(a,b,c,d) 1
-#define RTE_VERSION 0
-#endif
 #define VHOST_USER_PROTOCOL_FEATURES   ((1ULL << VHOST_USER_PROTOCOL_F_MQ) |	\
 					(1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD))
 
diff --git a/vnet/vnet/ip/ip.h b/vnet/vnet/ip/ip.h
index c9a82930..f50662b2 100644
--- a/vnet/vnet/ip/ip.h
+++ b/vnet/vnet/ip/ip.h
@@ -63,11 +63,6 @@
 #include <vnet/ip/ip6_packet.h>
 #include <vnet/ip/ip6_error.h>
 #include <vnet/ip/icmp6.h>
-
-#if DPDK > 0
-#include <vnet/devices/dpdk/dpdk.h>
-#endif
-
 #include <vnet/classify/vnet_classify.h>
 
 /* Per protocol info. */
@@ -155,35 +150,6 @@ ip_incremental_checksum_buffer (vlib_main_t * vm, vlib_buffer_t * first_buffer,
 				u32 first_buffer_offset,
 				u32 n_bytes_to_checksum,
 				ip_csum_t sum)
-#if DPDK > 0
-{
-  u32 n_bytes_left = n_bytes_to_checksum;
-  struct rte_mbuf * mb = rte_mbuf_from_vlib_buffer(first_buffer);
-  u8 nb_segs = mb->nb_segs;
-  ASSERT(mb->data_len >= first_buffer_offset);
-  void * h;
-  u32 n;
-  
-  n = clib_min (n_bytes_left, mb->data_len);
-  h = vlib_buffer_get_current (first_buffer) + first_buffer_offset;
-  while (n_bytes_left)
-    {
-      sum = ip_incremental_checksum (sum, h, n);
-      n_bytes_left -= n;
-      nb_segs--;
-      mb = mb->next;
-      if ((nb_segs == 0) || (mb == 0))
-	break;
-
-      n = clib_min (n_bytes_left, mb->data_len);
-      h = rte_ctrlmbuf_data(mb);
-    }
- 
-  ASSERT(n_bytes_left == 0);
-  ASSERT(nb_segs == 0);
-  return sum;
-}
-#else
 {
   vlib_buffer_t * b = first_buffer;
   u32 n_bytes_left = n_bytes_to_checksum;
@@ -210,7 +176,6 @@ ip_incremental_checksum_buffer (vlib_main_t * vm, vlib_buffer_t * first_buffer,
 
   return sum;
 }
-#endif /* DPDK */
 
 void ip_del_all_interface_addresses (vlib_main_t *vm, u32 sw_if_index);
 
diff --git a/vnet/vnet/ip/ip6_forward.c b/vnet/vnet/ip/ip6_forward.c
index 14dd9dfb..f3cd640a 100644
--- a/vnet/vnet/ip/ip6_forward.c
+++ b/vnet/vnet/ip/ip6_forward.c
@@ -1177,35 +1177,6 @@ u16 ip6_tcp_udp_icmp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0, ip6
    }
 
   n_bytes_left = n_this_buffer = payload_length_host_byte_order;
-#if DPDK > 0
-  if (p0 && n_this_buffer + headers_size  > p0->current_length)
-  {
-    struct rte_mbuf *mb = rte_mbuf_from_vlib_buffer(p0);
-    u8 nb_segs = mb->nb_segs;
-
-    n_this_buffer = (p0->current_length > headers_size ?
-		     p0->current_length - headers_size : 0);
-    while (n_bytes_left)
-      {
-	sum0 = ip_incremental_checksum (sum0, data_this_buffer, n_this_buffer);
-	n_bytes_left -= n_this_buffer;
-
-	mb = mb->next;
-	nb_segs--;
-	if ((nb_segs == 0) || (mb == 0))
-	  break;
-
-	data_this_buffer = rte_ctrlmbuf_data(mb);
-	n_this_buffer = mb->data_len;
-      }
-    if (n_bytes_left || nb_segs)
-      {
-	*bogus_lengthp = 1;
-	return 0xfefe;
-      }
-  }
-  else sum0 = ip_incremental_checksum (sum0, data_this_buffer, n_this_buffer);
-#else
   if (p0 && n_this_buffer + headers_size  > p0->current_length)
     n_this_buffer = p0->current_length > headers_size  ? p0->current_length - headers_size  : 0;
   while (1)
@@ -1224,7 +1195,6 @@ u16 ip6_tcp_udp_icmp_compute_checksum (vlib_main_t * vm, vlib_buffer_t * p0, ip6
       data_this_buffer = vlib_buffer_get_current (p0);
       n_this_buffer = p0->current_length;
     }
-#endif /* DPDK */
 
   sum16 = ~ ip_csum_fold (sum0);
 
diff --git a/vnet/vnet/ip/ip6_neighbor.c b/vnet/vnet/ip/ip6_neighbor.c
index af852a2b..cc176306 100644
--- a/vnet/vnet/ip/ip6_neighbor.c
+++ b/vnet/vnet/ip/ip6_neighbor.c
@@ -23,10 +23,6 @@
 #include <vnet/fib/fib_table.h>
 #include <vnet/fib/ip6_fib.h>
 
-#if DPDK==1
-#include <vnet/devices/dpdk/dpdk.h>
-#endif
-
 /**
  * @file
  * @brief IPv6 Neighbor Adjacency and Neighbor Discovery.
@@ -317,7 +313,6 @@ typedef struct {
   ip6_address_t addr;
 } ip6_neighbor_set_unset_rpc_args_t;
 
-#if DPDK > 0
 static void ip6_neighbor_set_unset_rpc_callback 
 ( ip6_neighbor_set_unset_rpc_args_t * a);
 
@@ -340,7 +335,6 @@ static void set_unset_ip6_neighbor_rpc
   vl_api_rpc_call_main_thread (ip6_neighbor_set_unset_rpc_callback,
                                (u8 *) &args, sizeof (args));
 }
-#endif
 
 static void
 ip6_nbr_probe (ip_adjacency_t *adj)
@@ -538,14 +532,12 @@ vnet_set_ip6_ethernet_neighbor (vlib_main_t * vm,
   u32 next_index;
   pending_resolution_t * pr, * mc;
 
-#if DPDK > 0
   if (os_get_cpu_number())
     {
       set_unset_ip6_neighbor_rpc (vm, sw_if_index, a, link_layer_address,
                                   1 /* set new neighbor */, is_static);
       return 0;
     }
-#endif
 
   k.sw_if_index = sw_if_index;
   k.ip6_address = a[0];
@@ -687,14 +679,12 @@ vnet_unset_ip6_ethernet_neighbor (vlib_main_t * vm,
   uword * p;
   int rv = 0;
 
-#if DPDK > 0
   if (os_get_cpu_number())
     {
       set_unset_ip6_neighbor_rpc (vm, sw_if_index, a, link_layer_address,
                                   0 /* unset */, 0);
       return 0;
     }
-#endif
 
   k.sw_if_index = sw_if_index;
   k.ip6_address = a[0];
@@ -722,7 +712,6 @@ vnet_unset_ip6_ethernet_neighbor (vlib_main_t * vm,
   return rv;
 }
 
-#if DPDK > 0
 static void ip6_neighbor_set_unset_rpc_callback 
 ( ip6_neighbor_set_unset_rpc_args_t * a)
 {
@@ -734,7 +723,6 @@ static void ip6_neighbor_set_unset_rpc_callback
     vnet_unset_ip6_ethernet_neighbor (vm, a->sw_if_index, &a->addr, 
                                       a->link_layer_address, 6);
 }
-#endif
 
 static int
 ip6_neighbor_sort (void *a1, void *a2)
diff --git a/vnet/vnet/ipsec/esp.h b/vnet/vnet/ipsec/esp.h
index 505d34ad..b9feacbb 100644
--- a/vnet/vnet/ipsec/esp.h
+++ b/vnet/vnet/ipsec/esp.h
@@ -12,9 +12,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-#if DPDK==1
-#include <vnet/devices/dpdk/dpdk.h>
-#endif
 
 #include <openssl/hmac.h>
 #include <openssl/rand.h>
diff --git a/vnet/vnet/ipsec/ipsec.h b/vnet/vnet/ipsec/ipsec.h
index dbbb928f..d33df383 100644
--- a/vnet/vnet/ipsec/ipsec.h
+++ b/vnet/vnet/ipsec/ipsec.h
@@ -12,10 +12,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-#if DPDK==1
-#include <vnet/devices/dpdk/dpdk.h>
-#endif
-
 #define IPSEC_FLAG_IPSEC_GRE_TUNNEL (1 << 0)
 
 #define foreach_ipsec_policy_action \
@@ -280,12 +276,6 @@ int ipsec_set_interface_key (vnet_main_t * vnm, u32 hw_if_index,
 always_inline void
 ipsec_alloc_empty_buffers (vlib_main_t * vm, ipsec_main_t * im)
 {
-#if DPDK==1
-  dpdk_main_t *dm = &dpdk_main;
-  u32 free_list_index = dm->vlib_buffer_free_list_index;
-#else
-  u32 free_list_index = VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX;
-#endif
   u32 cpu_index = os_get_cpu_number ();
   uword l = vec_len (im->empty_buffers[cpu_index]);
   uword n_alloc = 0;
@@ -297,11 +287,8 @@ ipsec_alloc_empty_buffers (vlib_main_t * vm, ipsec_main_t * im)
 	  vec_alloc (im->empty_buffers[cpu_index], 2 * VLIB_FRAME_SIZE);
 	}
 
-      n_alloc = vlib_buffer_alloc_from_free_list (vm,
-						  im->empty_buffers[cpu_index]
-						  + l,
-						  2 * VLIB_FRAME_SIZE - l,
-						  free_list_index);
+      n_alloc = vlib_buffer_alloc (vm, im->empty_buffers[cpu_index] + l,
+				   2 * VLIB_FRAME_SIZE - l);
 
       _vec_len (im->empty_buffers[cpu_index]) = l + n_alloc;
     }
diff --git a/vnet/vnet/l2/l2_output.c b/vnet/vnet/l2/l2_output.c
index f8ebe146..22ce663b 100644
--- a/vnet/vnet/l2/l2_output.c
+++ b/vnet/vnet/l2/l2_output.c
@@ -614,7 +614,6 @@ typedef struct
   u32 sw_if_index;
 } output_node_mapping_rpc_args_t;
 
-#if DPDK > 0
 static void output_node_rpc_callback (output_node_mapping_rpc_args_t * a);
 
 static void
@@ -629,7 +628,6 @@ output_node_mapping_send_rpc (u32 node_index, u32 sw_if_index)
   vl_api_rpc_call_main_thread (output_node_rpc_callback,
 			       (u8 *) & args, sizeof (args));
 }
-#endif
 
 
 /** Create a mapping in the next node mapping table for the given sw_if_index. */
@@ -645,7 +643,6 @@ l2output_create_output_node_mapping (vlib_main_t * vlib_main, vnet_main_t * vnet
 
   hw0 = vnet_get_sup_hw_interface (vnet_main, sw_if_index);
 
-#if DPDK > 0
   uword cpu_number;
 
   cpu_number = os_get_cpu_number ();
@@ -663,7 +660,6 @@ l2output_create_output_node_mapping (vlib_main_t * vlib_main, vnet_main_t * vnet
       output_node_mapping_send_rpc (node_index, sw_if_index);
       return L2OUTPUT_NEXT_DROP;
     }
-#endif
 
   /* dynamically create graph node arc  */
   next = vlib_node_add_next (vlib_main, node_index, hw0->output_node_index);
@@ -679,7 +675,6 @@ l2output_create_output_node_mapping (vlib_main_t * vlib_main, vnet_main_t * vnet
   return next;
 }
 
-#if DPDK > 0
 void
 output_node_rpc_callback (output_node_mapping_rpc_args_t * a)
 {
@@ -691,7 +686,6 @@ output_node_rpc_callback (output_node_mapping_rpc_args_t * a)
     (vm, vnm, a->node_index, mp->next_nodes.output_node_index_vec,
      a->sw_if_index);
 }
-#endif
 
 /* Get a pointer to the config for the given interface */
 l2_output_config_t *
diff --git a/vnet/vnet/pg/input.c b/vnet/vnet/pg/input.c
index 54687d51..77b56f52 100644
--- a/vnet/vnet/pg/input.c
+++ b/vnet/vnet/pg/input.c
@@ -43,39 +43,6 @@
 #include <vnet/feature/feature.h>
 #include <vnet/devices/devices.h>
 
-#if DPDK==1
-#include <vnet/devices/dpdk/dpdk.h>
-#endif
-
-static inline void
-pg_set_mbuf_metadata (pg_main_t * pg, u32 * buffers, u32 n_alloc)
-{
-#if DPDK == 1
-  vlib_main_t *vm = vlib_get_main ();
-  vlib_buffer_t *b;
-  struct rte_mbuf *mb;
-  i16 delta;
-  u16 new_data_len;
-  u16 new_pkt_len;
-
-  int i;
-
-  for (i = 0; i < n_alloc; i++)
-    {
-      b = vlib_get_buffer (vm, buffers[i]);
-      mb = rte_mbuf_from_vlib_buffer (b);
-
-      delta = vlib_buffer_length_in_chain (vm, b) - (i16) mb->pkt_len;
-      new_data_len = (u16) ((i16) mb->data_len + delta);
-      new_pkt_len = (u16) ((i16) mb->pkt_len + delta);
-
-      mb->data_len = new_data_len;
-      mb->pkt_len = new_pkt_len;
-      mb->data_off = (u16) ((RTE_PKTMBUF_HEADROOM) + b->current_data);
-    }
-#endif
-}
-
 static int
 validate_buffer_data2 (vlib_buffer_t * b, pg_stream_t * s,
 		       u32 data_offset, u32 n_bytes)
@@ -930,7 +897,6 @@ pg_generate_set_lengths (pg_main_t * pg,
 				     si->sw_if_index, n_buffers, length_sum);
   }
 
-  pg_set_mbuf_metadata (pg, buffers, n_buffers);
 }
 
 static void
@@ -1398,24 +1364,6 @@ pg_stream_fill (pg_main_t * pg, pg_stream_t * s, u32 n_buffers)
       last_start = start;
 
       /* Verify that pkts in the fifo are properly allocated */
-#if DPDK == 1
-      if (CLIB_DEBUG > 0)
-	{
-	  u32 *bi0;
-	  vlib_main_t *vm = vlib_get_main ();
-	  /* *INDENT-OFF* */
-          clib_fifo_foreach (bi0, bi->buffer_fifo,
-          ({
-            vlib_buffer_t * b;
-            struct rte_mbuf *mb;
-
-            b = vlib_get_buffer(vm, bi0[0]);
-            mb = rte_mbuf_from_vlib_buffer(b);
-            ASSERT(rte_mbuf_refcnt_read(mb) == 1);
-          }));
-	  /* *INDENT-ON* */
-	}
-#endif
     }
 
   return n_in_fifo + n_added;
diff --git a/vnet/vnet/unix/tapcli.c b/vnet/vnet/unix/tapcli.c
index d23e6fea..db634f71 100644
--- a/vnet/vnet/unix/tapcli.c
+++ b/vnet/vnet/unix/tapcli.c
@@ -39,10 +39,6 @@
 
 #include <vnet/ethernet/ethernet.h>
 
-#if DPDK == 1
-#include <vnet/devices/dpdk/dpdk.h>
-#endif
-
 #include <vnet/feature/feature.h>
 #include <vnet/devices/devices.h>
 #include <vnet/unix/tapcli.h>
@@ -343,9 +339,6 @@ static uword tapcli_rx_iface(vlib_main_t * vm,
         (n_bytes_in_packet > buffer_size) ? n_bytes_in_packet - buffer_size : 0;
     b_first->flags |= VLIB_BUFFER_TOTAL_LENGTH_VALID;
 
-    /* Ensure mbufs are updated */
-    vlib_buffer_chain_validate(vm, b_first);
-
     VLIB_BUFFER_TRACE_TRAJECTORY_INIT(b_first);
 
     vnet_buffer (b_first)->sw_if_index[VLIB_RX] = ti->sw_if_index;
diff --git a/vnet/vnet/unix/tuntap.c b/vnet/vnet/unix/tuntap.c
index dbb6f309..4a5dd676 100644
--- a/vnet/vnet/unix/tuntap.c
+++ b/vnet/vnet/unix/tuntap.c
@@ -50,10 +50,6 @@
 #include <vnet/devices/devices.h>
 #include <vnet/feature/feature.h>
 
-#if DPDK == 1
-#include <vnet/devices/dpdk/dpdk.h>
-#endif
-
 static vnet_device_class_t tuntap_dev_class;
 static vnet_hw_interface_class_t tuntap_interface_class;
 
@@ -233,13 +229,6 @@ tuntap_rx (vlib_main_t * vm,
   vlib_buffer_t * b;
   u32 bi;
   const uword buffer_size = VLIB_BUFFER_DATA_SIZE;
-#if DPDK == 0
-  u32 free_list_index = VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX;
-#else
-  dpdk_main_t * dm = &dpdk_main;
-  u32 free_list_index = dm->vlib_buffer_free_list_index;
-  struct rte_mbuf *first_mb = NULL, *prev_mb = NULL;
-#endif
 
   /** Make sure we have some RX buffers. */
   {
@@ -251,9 +240,7 @@ tuntap_rx (vlib_main_t * vm,
 	if (! tm->rx_buffers)
 	  vec_alloc (tm->rx_buffers, VLIB_FRAME_SIZE);
 
-	n_alloc = vlib_buffer_alloc_from_free_list 
-            (vm, tm->rx_buffers + n_left, VLIB_FRAME_SIZE - n_left, 
-             free_list_index);
+	n_alloc = vlib_buffer_alloc (vm, tm->rx_buffers + n_left, VLIB_FRAME_SIZE - n_left);
 	_vec_len (tm->rx_buffers) = n_left + n_alloc;
       }
   }
@@ -289,46 +276,21 @@ tuntap_rx (vlib_main_t * vm,
 
     while (1)
       {
-#if DPDK == 1
-        struct rte_mbuf * mb;
-#endif
 	b = vlib_get_buffer (vm, tm->rx_buffers[i_rx]);
-#if DPDK == 1
-	mb = rte_mbuf_from_vlib_buffer(b);
-
-        if (first_mb == NULL)
-            first_mb = mb;
-
-        if (prev_mb != NULL)
-          {
-            prev_mb->next = mb;
-            first_mb->nb_segs++;
-          }
-#endif
 	b->flags = 0;
 	b->current_data = 0;
 	b->current_length = n_bytes_left < buffer_size ? n_bytes_left : buffer_size;
 
 	n_bytes_left -= buffer_size;
-#if DPDK == 1
-        rte_pktmbuf_data_len (mb) = b->current_length;
-        mb->data_off = RTE_PKTMBUF_HEADROOM + b->current_data;
-#endif
 
 	if (n_bytes_left <= 0)
           {
-#if DPDK == 1
-            rte_pktmbuf_pkt_len (first_mb) = n_bytes_in_packet;
-#endif
             break;
           }
 
 	i_rx--;
 	b->flags |= VLIB_BUFFER_NEXT_PRESENT;
 	b->next_buffer = tm->rx_buffers[i_rx];
-#if DPDK == 1
-        prev_mb = mb;
-#endif
       }
 
     /** Interface counters for tuntap interface. */