buffers: make buffer data size configurable from startup config

Example:

buffers {
	default data-size 1536
}

Change-Id: I5b4436850ca18025c9fdcfc7ed648c2c2732d660
Signed-off-by: Damjan Marion <damarion@cisco.com>
diff --git a/src/vnet/devices/af_packet/node.c b/src/vnet/devices/af_packet/node.c
index 243a38a..2fa7708 100644
--- a/src/vnet/devices/af_packet/node.c
+++ b/src/vnet/devices/af_packet/node.c
@@ -192,7 +192,7 @@
   u8 *block_start = apif->rx_ring + block * block_size;
   uword n_trace = vlib_get_trace_count (vm, node);
   u32 thread_index = vm->thread_index;
-  u32 n_buffer_bytes = VLIB_BUFFER_DATA_SIZE;
+  u32 n_buffer_bytes = vlib_bufer_get_default_size (vm);
   u32 min_bufs = apif->rx_req->tp_frame_size / n_buffer_bytes;
 
   if (apif->per_interface_next_index != ~0)
diff --git a/src/vnet/devices/netmap/node.c b/src/vnet/devices/netmap/node.c
index 577d4a3..122d8c3 100644
--- a/src/vnet/devices/netmap/node.c
+++ b/src/vnet/devices/netmap/node.c
@@ -99,7 +99,7 @@
   struct netmap_ring *ring;
   int cur_ring;
   u32 thread_index = vm->thread_index;
-  u32 n_buffer_bytes = VLIB_BUFFER_DATA_SIZE;
+  u32 n_buffer_bytes = vlib_bufer_get_default_size (vm);
 
   if (nif->per_interface_next_index != ~0)
     next_index = nif->per_interface_next_index;
diff --git a/src/vnet/devices/virtio/node.c b/src/vnet/devices/virtio/node.c
index 78d071a..fc369e5 100644
--- a/src/vnet/devices/virtio/node.c
+++ b/src/vnet/devices/virtio/node.c
@@ -120,7 +120,7 @@
 	((vif->type == VIRTIO_IF_TYPE_PCI) ? vlib_buffer_get_current_pa (vm,
 									 b) :
 	 pointer_to_uword (vlib_buffer_get_current (b)));
-      d->len = VLIB_BUFFER_DATA_SIZE + hdr_sz;
+      d->len = vlib_bufer_get_default_size (vm) + hdr_sz;
       d->flags = VRING_DESC_F_WRITE;
       vring->avail->ring[avail & mask] = next;
       avail++;
diff --git a/src/vnet/devices/virtio/vhost_user_input.c b/src/vnet/devices/virtio/vhost_user_input.c
index 812f9d3..465ec44 100644
--- a/src/vnet/devices/virtio/vhost_user_input.c
+++ b/src/vnet/devices/virtio/vhost_user_input.c
@@ -501,7 +501,7 @@
 
 	  /* Get more output if necessary. Or end of packet. */
 	  if (PREDICT_FALSE
-	      (b_current->current_length == VLIB_BUFFER_DATA_SIZE))
+	      (b_current->current_length == vlib_bufer_get_default_size (vm)))
 	    {
 	      if (PREDICT_FALSE (cpu->rx_buffers_len == 0))
 		{
@@ -534,7 +534,8 @@
 	  vhost_copy_t *cpy = &cpu->copy[copy_len];
 	  copy_len++;
 	  u32 desc_data_l = desc_table[desc_current].len - desc_data_offset;
-	  cpy->len = VLIB_BUFFER_DATA_SIZE - b_current->current_length;
+	  cpy->len =
+	    vlib_bufer_get_default_size (vm) - b_current->current_length;
 	  cpy->len = (cpy->len > desc_data_l) ? desc_data_l : cpy->len;
 	  cpy->dst = (uword) (vlib_buffer_get_current (b_current) +
 			      b_current->current_length);
diff --git a/src/vnet/dhcp/dhcp6_proxy_node.c b/src/vnet/dhcp/dhcp6_proxy_node.c
index 92e011b..e4464e0 100644
--- a/src/vnet/dhcp/dhcp6_proxy_node.c
+++ b/src/vnet/dhcp/dhcp6_proxy_node.c
@@ -316,7 +316,7 @@
 	link_address_set:
 
 	  if ((b0->current_length + sizeof (*id1) + sizeof (*vss1) +
-	       sizeof (*cmac)) > VLIB_BUFFER_DATA_SIZE)
+	       sizeof (*cmac)) > vlib_bufer_get_default_size (vm))
 	    {
 	      error0 = DHCPV6_PROXY_ERROR_PKT_TOO_BIG;
 	      next0 = DHCPV6_PROXY_TO_SERVER_INPUT_NEXT_DROP;
diff --git a/src/vnet/ip/ip_frag.c b/src/vnet/ip/ip_frag.c
index de29776..6ecaa3c 100644
--- a/src/vnet/ip/ip_frag.c
+++ b/src/vnet/ip/ip_frag.c
@@ -106,7 +106,8 @@
 
   rem = clib_net_to_host_u16 (ip4->length) - sizeof (ip4_header_t);
   max =
-    (clib_min (mtu, VLIB_BUFFER_DATA_SIZE) - sizeof (ip4_header_t)) & ~0x7;
+    (clib_min (mtu, vlib_bufer_get_default_size (vm)) -
+     sizeof (ip4_header_t)) & ~0x7;
 
   if (rem >
       (vlib_buffer_length_in_chain (vm, from_b) - sizeof (ip4_header_t)))
diff --git a/src/vnet/ip/ping.c b/src/vnet/ip/ping.c
index 890285f..90314b5 100755
--- a/src/vnet/ip/ping.c
+++ b/src/vnet/ip/ping.c
@@ -388,7 +388,7 @@
   int l34_len =
     l4_header_offset + sizeof (icmp46_header_t) +
     offsetof (icmp46_echo_request_t, data);
-  int max_data_len = VLIB_BUFFER_DATA_SIZE - l34_len;
+  int max_data_len = vlib_bufer_get_default_size (vm) - l34_len;
 
   int first_buf_data_len = data_len < max_data_len ? data_len : max_data_len;
 
@@ -403,7 +403,8 @@
     {
       int this_buf_data_len =
 	remaining_data_len <
-	VLIB_BUFFER_DATA_SIZE ? remaining_data_len : VLIB_BUFFER_DATA_SIZE;
+	vlib_bufer_get_default_size (vm) ? remaining_data_len :
+	vlib_bufer_get_default_size (vm);
       int n_alloc = vlib_buffer_alloc (vm, &b0->next_buffer, 1);
       if (n_alloc < 1)
 	{
diff --git a/src/vnet/ip/punt.c b/src/vnet/ip/punt.c
index 65e62c0..8331a87 100644
--- a/src/vnet/ip/punt.c
+++ b/src/vnet/ip/punt.c
@@ -497,7 +497,7 @@
 static uword
 punt_socket_rx_fd (vlib_main_t * vm, vlib_node_runtime_t * node, u32 fd)
 {
-  const uword buffer_size = VLIB_BUFFER_DATA_SIZE;
+  const uword buffer_size = vlib_bufer_get_default_size (vm);
   u32 n_trace = vlib_get_trace_count (vm, node);
   u32 next = node->cached_next_index;
   u32 n_left_to_next, next_index;
diff --git a/src/vnet/ipfix-export/flow_report.c b/src/vnet/ipfix-export/flow_report.c
index da91a7c..9d0834b 100644
--- a/src/vnet/ipfix-export/flow_report.c
+++ b/src/vnet/ipfix-export/flow_report.c
@@ -121,7 +121,7 @@
   /* Initialize the buffer */
   VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b0);
 
-  ASSERT (vec_len (fr->rewrite) < VLIB_BUFFER_DATA_SIZE);
+  ASSERT (vec_len (fr->rewrite) < vlib_bufer_get_default_size (vm));
 
   clib_memcpy_fast (b0->data, fr->rewrite, vec_len (fr->rewrite));
   b0->current_data = 0;
diff --git a/src/vnet/pg/cli.c b/src/vnet/pg/cli.c
index bca0551..4053887 100644
--- a/src/vnet/pg/cli.c
+++ b/src/vnet/pg/cli.c
@@ -341,7 +341,7 @@
   s.sw_if_index[VLIB_RX] = s.sw_if_index[VLIB_TX] = ~0;
   s.node_index = ~0;
   s.max_packet_bytes = s.min_packet_bytes = 64;
-  s.buffer_bytes = VLIB_BUFFER_DATA_SIZE;
+  s.buffer_bytes = vlib_bufer_get_default_size (vm);
   s.if_id = 0;
   pcap_file_name = 0;
   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
diff --git a/src/vnet/pg/input.c b/src/vnet/pg/input.c
index 6088b91..6ef813f 100644
--- a/src/vnet/pg/input.c
+++ b/src/vnet/pg/input.c
@@ -1199,6 +1199,7 @@
   u32 *buffers;
   vlib_main_t *vm = vlib_get_main ();
   vnet_main_t *vnm = vnet_get_main ();
+  u32 buf_sz = vlib_bufer_get_default_size (vm);
   vnet_interface_main_t *im = &vnm->interface_main;
   vnet_sw_interface_t *si;
 
@@ -1216,8 +1217,7 @@
       u8 *d0;
 
       d0 = vec_elt (s->replay_packet_templates, i);
-      buffer_alloc_request += (vec_len (d0) + (VLIB_BUFFER_DATA_SIZE - 1))
-	/ VLIB_BUFFER_DATA_SIZE;
+      buffer_alloc_request += (vec_len (d0) + (buf_sz - 1)) / buf_sz;
 
       i = ((i + 1) == l) ? 0 : i + 1;
       n_left--;
@@ -1261,7 +1261,7 @@
       /* Copy the data */
       while (bytes_to_copy)
 	{
-	  bytes_this_chunk = clib_min (bytes_to_copy, VLIB_BUFFER_DATA_SIZE);
+	  bytes_this_chunk = clib_min (bytes_to_copy, buf_sz);
 	  ASSERT (current_buffer_index < vec_len (buffers));
 	  b = vlib_get_buffer (vm, buffers[current_buffer_index]);
 	  clib_memcpy_fast (b->data, d0 + data_offset, bytes_this_chunk);
diff --git a/src/vnet/pg/stream.c b/src/vnet/pg/stream.c
index c91caca..ba24912 100644
--- a/src/vnet/pg/stream.c
+++ b/src/vnet/pg/stream.c
@@ -437,7 +437,7 @@
   {
     int n;
 
-    s->buffer_bytes = VLIB_BUFFER_DATA_SIZE;
+    s->buffer_bytes = vlib_bufer_get_default_size (vm);
     n = s->max_packet_bytes / s->buffer_bytes;
     n += (s->max_packet_bytes % s->buffer_bytes) != 0;
 
diff --git a/src/vnet/sctp/sctp.c b/src/vnet/sctp/sctp.c
index d0e28c5..21cc78b 100644
--- a/src/vnet/sctp/sctp.c
+++ b/src/vnet/sctp/sctp.c
@@ -892,7 +892,7 @@
   vec_validate (tm->ip_lookup_tx_frames[0], num_threads - 1);
   vec_validate (tm->ip_lookup_tx_frames[1], num_threads - 1);
 
-  tm->bytes_per_buffer = VLIB_BUFFER_DATA_SIZE;
+  tm->bytes_per_buffer = vlib_bufer_get_default_size (vm);
 
   vec_validate (tm->time_now, num_threads - 1);
   return error;
diff --git a/src/vnet/session/session_node.c b/src/vnet/session/session_node.c
index 286bd7b..09adc59 100644
--- a/src/vnet/session/session_node.c
+++ b/src/vnet/session/session_node.c
@@ -605,7 +605,7 @@
       ctx->max_len_to_snd = max_segs * ctx->snd_mss;
     }
 
-  n_bytes_per_buf = VLIB_BUFFER_DATA_SIZE;
+  n_bytes_per_buf = vlib_bufer_get_default_size (vm);
   ASSERT (n_bytes_per_buf > TRANSPORT_MAX_HDRS_LEN);
   n_bytes_per_seg = TRANSPORT_MAX_HDRS_LEN + ctx->snd_mss;
   ctx->n_bufs_per_seg = ceil ((f64) n_bytes_per_seg / n_bytes_per_buf);
diff --git a/src/vnet/tcp/tcp.c b/src/vnet/tcp/tcp.c
index 5fdeec6..ee5f275 100644
--- a/src/vnet/tcp/tcp.c
+++ b/src/vnet/tcp/tcp.c
@@ -1476,7 +1476,7 @@
   tcp_initialize_timer_wheels (tm);
   tcp_initialize_iss_seed (tm);
 
-  tm->bytes_per_buffer = VLIB_BUFFER_DATA_SIZE;
+  tm->bytes_per_buffer = vlib_bufer_get_default_size (vm);
 
   return error;
 }
diff --git a/src/vnet/unix/tuntap.c b/src/vnet/unix/tuntap.c
index e002a24..ce7b260 100644
--- a/src/vnet/unix/tuntap.c
+++ b/src/vnet/unix/tuntap.c
@@ -243,7 +243,7 @@
   tuntap_main_t *tm = &tuntap_main;
   vlib_buffer_t *b;
   u32 bi;
-  const uword buffer_size = VLIB_BUFFER_DATA_SIZE;
+  const uword buffer_size = vlib_bufer_get_default_size (vm);
   u16 thread_index = vm->thread_index;
 
   /** Make sure we have some RX buffers. */
@@ -490,7 +490,7 @@
   u8 *name;
   int flags = IFF_TUN | IFF_NO_PI;
   int is_enabled = 0, is_ether = 0, have_normal_interface = 0;
-  const uword buffer_size = VLIB_BUFFER_DATA_SIZE;
+  const uword buffer_size = vlib_bufer_get_default_size (vm);
 
   while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
     {