vxlan:encap - use vnet rewrite

moving the rewrite into the tunnel struct

Change-Id: Iec74b48e13456d32957e826cffb5ea35a8ebd1a0
Signed-off-by: Eyal Bari <ebari@cisco.com>

3 files changed, 50 insertions, 53 deletions

diff --git a/src/vnet/vxlan/encap.c b/src/vnet/vxlan/encap.c
index f9871d533ff..c34b0e67221 100644
--- a/src/vnet/vxlan/encap.c
+++ b/src/vnet/vxlan/encap.c
@@ -20,6 +20,7 @@
 #include <vnet/ethernet/ethernet.h>
 #include <vnet/vxlan/vxlan.h>
 #include <vnet/qos/qos_types.h>
+#include <vnet/adj/rewrite.h>
 
 /* Statistics (not all errors) */
 #define foreach_vxlan_encap_error    \
@@ -87,8 +88,9 @@ vxlan_encap_inline (vlib_main_t * vm,
   STATIC_ASSERT_SIZEOF(ip6_vxlan_header_t, 56);
   STATIC_ASSERT_SIZEOF(ip4_vxlan_header_t, 36);
 
-  word const underlay_hdr_len = is_ip4 ?
+  u8 const underlay_hdr_len = is_ip4 ?
     sizeof(ip4_vxlan_header_t) : sizeof(ip6_vxlan_header_t);
+  u8 const rw_hdr_offset = sizeof t0->rewrite_data - underlay_hdr_len;
   u16 const l3_len = is_ip4 ? sizeof(ip4_header_t) : sizeof(ip6_header_t);
   u32 const csum_flags = is_ip4 ?
     VNET_BUFFER_F_OFFLOAD_IP_CKSUM | VNET_BUFFER_F_IS_IP4 |
@@ -118,21 +120,18 @@ vxlan_encap_inline (vlib_main_t * vm,
 	    CLIB_PREFETCH (p3->data, 2*CLIB_CACHE_LINE_BYTES, LOAD);
 	  }
 
-	  u32 bi0 = from[0];
-	  u32 bi1 = from[1];
+	  u32 bi0 = to_next[0] = from[0];
+	  u32 bi1 = to_next[1] = from[1];
+	  from += 2;
+	  to_next += 2;
+	  n_left_to_next -= 2;
+	  n_left_from -= 2;
 
 	  vlib_buffer_t * b0 = vlib_get_buffer (vm, bi0);
 	  vlib_buffer_t * b1 = vlib_get_buffer (vm, bi1);
           u32 flow_hash0 = vnet_l2_compute_flow_hash (b0);
           u32 flow_hash1 = vnet_l2_compute_flow_hash (b1);
 
-	  to_next[0] = bi0;
-	  to_next[1] = bi1;
-	  from += 2;
-	  to_next += 2;
-	  n_left_to_next -= 2;
-	  n_left_from -= 2;
-
 	  /* Get next node index and adj index from tunnel next_dpo */
 	  if (sw_if_index0 != vnet_buffer(b0)->sw_if_index[VLIB_TX])
 	    {
@@ -170,8 +169,8 @@ vxlan_encap_inline (vlib_main_t * vm,
           vnet_buffer(b0)->ip.adj_index[VLIB_TX] = dpoi_idx0;
           vnet_buffer(b1)->ip.adj_index[VLIB_TX] = dpoi_idx1;
 
-          ASSERT(vec_len(t0->rewrite) == underlay_hdr_len);
-          ASSERT(vec_len(t1->rewrite) == underlay_hdr_len);
+          ASSERT(t0->rewrite_header.data_bytes == underlay_hdr_len);
+          ASSERT(t1->rewrite_header.data_bytes == underlay_hdr_len);
 
           vlib_buffer_advance (b0, -underlay_hdr_len);
           vlib_buffer_advance (b1, -underlay_hdr_len);
@@ -181,6 +180,15 @@ vxlan_encap_inline (vlib_main_t * vm,
           u16 payload_l0 = clib_host_to_net_u16 (len0 - l3_len);
           u16 payload_l1 = clib_host_to_net_u16 (len1 - l3_len);
 
+          void * underlay0 = vlib_buffer_get_current(b0);
+          void * underlay1 = vlib_buffer_get_current(b1);
+
+	  /* vnet_rewrite_two_header writes only in (uword) 8 bytes chunks
+           * and discards the first 4 bytes of the (36 bytes ip4 underlay)  rewrite
+           * use memcpy as a workaround */
+          clib_memcpy(underlay0, t0->rewrite_header.data + rw_hdr_offset, underlay_hdr_len);
+          clib_memcpy(underlay1, t1->rewrite_header.data + rw_hdr_offset, underlay_hdr_len);
+
           ip4_header_t * ip4_0, * ip4_1;
 	  qos_bits_t ip4_0_tos = 0, ip4_1_tos = 0;
           ip6_header_t * ip6_0, * ip6_1;
@@ -188,12 +196,8 @@ vxlan_encap_inline (vlib_main_t * vm,
           u8 * l3_0, * l3_1;
 	  if (is_ip4)
 	    {
-              ip4_vxlan_header_t * hdr0 = vlib_buffer_get_current(b0);
-              ip4_vxlan_header_t * rewrite0 = (void *)t0->rewrite;
-              ip4_vxlan_header_t * hdr1 = vlib_buffer_get_current(b1);
-              ip4_vxlan_header_t * rewrite1 = (void *)t1->rewrite;
-              *hdr0 = *rewrite0;
-              *hdr1 = *rewrite1;
+              ip4_vxlan_header_t * hdr0 = underlay0;
+              ip4_vxlan_header_t * hdr1 = underlay1;
 
 	      /* Fix the IP4 checksum and length */
 	      ip4_0 = &hdr0->ip4;
@@ -219,12 +223,8 @@ vxlan_encap_inline (vlib_main_t * vm,
 	    }
 	  else /* ipv6 */
 	    {
-              ip6_vxlan_header_t * hdr0 = vlib_buffer_get_current(b0);
-              ip6_vxlan_header_t * rewrite0 = (void *) t0->rewrite;
-              ip6_vxlan_header_t * hdr1 = vlib_buffer_get_current(b0);
-              ip6_vxlan_header_t * rewrite1 = (void *) t1->rewrite;
-              *hdr0 = *rewrite0;
-              *hdr1 = *rewrite1;
+              ip6_vxlan_header_t * hdr0 = underlay0;
+              ip6_vxlan_header_t * hdr1 = underlay1;
 
 	      /* Fix IP6 payload length */
               ip6_0 = &hdr0->ip6;
@@ -321,16 +321,15 @@ vxlan_encap_inline (vlib_main_t * vm,
 
       while (n_left_from > 0 && n_left_to_next > 0)
 	{
-	  u32 bi0 = from[0];
-	  vlib_buffer_t * b0 = vlib_get_buffer (vm, bi0);
-          u32 flow_hash0 = vnet_l2_compute_flow_hash(b0);
-
-	  to_next[0] = bi0;
+	  u32 bi0 = to_next[0] = from[0];
 	  from += 1;
 	  to_next += 1;
 	  n_left_from -= 1;
 	  n_left_to_next -= 1;
 
+	  vlib_buffer_t * b0 = vlib_get_buffer (vm, bi0);
+          u32 flow_hash0 = vnet_l2_compute_flow_hash(b0);
+
 	  /* Get next node index and adj index from tunnel next_dpo */
 	  if (sw_if_index0 != vnet_buffer(b0)->sw_if_index[VLIB_TX])
 	    {
@@ -344,8 +343,15 @@ vxlan_encap_inline (vlib_main_t * vm,
 	    }
 	  vnet_buffer(b0)->ip.adj_index[VLIB_TX] = dpoi_idx0;
 
-          ASSERT(vec_len(t0->rewrite) == underlay_hdr_len);
+          ASSERT(t0->rewrite_header.data_bytes == underlay_hdr_len);
+
           vlib_buffer_advance (b0, -underlay_hdr_len);
+          void * underlay0 = vlib_buffer_get_current(b0);
+
+	  /* vnet_rewrite_one_header writes only in (uword) 8 bytes chunks
+           * and discards the first 4 bytes of the (36 bytes ip4 underlay)  rewrite
+           * use memcpy as a workaround */
+          clib_memcpy(underlay0, t0->rewrite_header.data + rw_hdr_offset, underlay_hdr_len);
 
  	  u32 len0 = vlib_buffer_length_in_chain (vm, b0);
           u16 payload_l0 = clib_host_to_net_u16 (len0 - l3_len);
@@ -357,9 +363,7 @@ vxlan_encap_inline (vlib_main_t * vm,
           u8 * l3_0;
 	  if (is_ip4)
 	    {
-              ip4_vxlan_header_t * rewrite = (void *)t0->rewrite;
-              ip4_vxlan_header_t * hdr = vlib_buffer_get_current(b0);
-              *hdr = *rewrite;
+              ip4_vxlan_header_t * hdr = underlay0;
 
 	      /* Fix the IP4 checksum and length */
               ip4_0 = &hdr->ip4;
@@ -376,9 +380,7 @@ vxlan_encap_inline (vlib_main_t * vm,
 	    }
 	  else /* ip6 path */
 	    {
-              ip6_vxlan_header_t * hdr = vlib_buffer_get_current(b0);
-              ip6_vxlan_header_t * rewrite = (void *) t0->rewrite;
-              *hdr = *rewrite;
+              ip6_vxlan_header_t * hdr = underlay0;
 
 	      /* Fix IP6 payload length */
               ip6_0 = &hdr->ip6;
diff --git a/src/vnet/vxlan/vxlan.c b/src/vnet/vxlan/vxlan.c
index 3d9a3edd7dc..ed5406c8fc0 100644
--- a/src/vnet/vxlan/vxlan.c
+++ b/src/vnet/vxlan/vxlan.c
@@ -18,6 +18,7 @@
 #include <vnet/fib/fib_table.h>
 #include <vnet/mfib/mfib_table.h>
 #include <vnet/adj/adj_mcast.h>
+#include <vnet/adj/rewrite.h>
 #include <vnet/interface.h>
 #include <vlib/vlib.h>
 
@@ -218,21 +219,18 @@ static void
 vxlan_rewrite (vxlan_tunnel_t * t, bool is_ip6)
 {
   union {
-    ip4_vxlan_header_t * h4;
-    ip6_vxlan_header_t * h6;
-    u8 *rw;
-  } r = { .rw = 0 };
-  int len = is_ip6 ? sizeof *r.h6 : sizeof *r.h4;
-
-  vec_validate_aligned (r.rw, len-1, CLIB_CACHE_LINE_BYTES);
+    ip4_vxlan_header_t h4;
+    ip6_vxlan_header_t h6;
+  } h = {0};
+  int len = is_ip6 ? sizeof h.h6 : sizeof h.h4;
 
   udp_header_t * udp;
   vxlan_header_t * vxlan;
   /* Fixed portion of the (outer) ip header */
   if (!is_ip6) 
     {
-      ip4_header_t * ip = &r.h4->ip4;
-      udp = &r.h4->udp, vxlan = &r.h4->vxlan;
+      ip4_header_t * ip = &h.h4.ip4;
+      udp = &h.h4.udp, vxlan = &h.h4.vxlan;
       ip->ip_version_and_header_length = 0x45;
       ip->ttl = 254;
       ip->protocol = IP_PROTOCOL_UDP;
@@ -245,8 +243,8 @@ vxlan_rewrite (vxlan_tunnel_t * t, bool is_ip6)
     }
   else
     {
-      ip6_header_t * ip = &r.h6->ip6;
-      udp = &r.h6->udp, vxlan = &r.h6->vxlan;
+      ip6_header_t * ip = &h.h6.ip6;
+      udp = &h.h6.udp, vxlan = &h.h6.vxlan;
       ip->ip_version_traffic_class_and_flow_label = clib_host_to_net_u32(6 << 28);
       ip->hop_limit = 255;
       ip->protocol = IP_PROTOCOL_UDP;
@@ -261,8 +259,7 @@ vxlan_rewrite (vxlan_tunnel_t * t, bool is_ip6)
 
   /* VXLAN header */
   vnet_set_vni_and_flags(vxlan, t->vni);
-
-  t->rewrite = r.rw;
+  vnet_rewrite_set_data (*t, &h, len);
 }
 
 static bool
@@ -573,7 +570,6 @@ int vnet_vxlan_add_del_tunnel
       hash_unset (vxm->instance_used, t->user_instance);
 
       fib_node_deinit(&t->node);
-      vec_free (t->rewrite);
       pool_put (vxm->tunnels, t);
     }
 
diff --git a/src/vnet/vxlan/vxlan.h b/src/vnet/vxlan/vxlan.h
index e8bb272d759..8fb031d4af5 100644
--- a/src/vnet/vxlan/vxlan.h
+++ b/src/vnet/vxlan/vxlan.h
@@ -66,9 +66,6 @@ typedef CLIB_PACKED(struct {
 }) vxlan6_tunnel_key_t;
 
 typedef struct {
-  /* Rewrite string. $$$$ embed vnet_rewrite header */
-  u8 * rewrite;
-
   /* FIB DPO for IP forwarding of VXLAN encap packet */
   dpo_id_t next_dpo;  
 
@@ -114,6 +111,8 @@ typedef struct {
 
   u32 dev_instance;	/* Real device instance in tunnel vector */
   u32 user_instance;	/* Instance name being shown to user */
+
+  vnet_declare_rewrite (VLIB_BUFFER_PRE_DATA_SIZE);
 } vxlan_tunnel_t;
 
 #define foreach_vxlan_input_next        \