Adjacency layout change and move to vnet/adj

Change-Id: I03195a86c69f84a301051c6b3ab64456bbf28645
Signed-off-by: Neale Ranns <nranns@cisco.com>

1 files changed, 350 insertions, 0 deletions

diff --git a/src/vnet/adj/rewrite.h b/src/vnet/adj/rewrite.h
new file mode 100644
index 00000000000..1dea72f5ed8
--- /dev/null
+++ b/src/vnet/adj/rewrite.h
@@ -0,0 +1,350 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+/*
+ * rewrite.h: packet rewrite
+ *
+ * Copyright (c) 2008 Eliot Dresselhaus
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef included_vnet_rewrite_h
+#define included_vnet_rewrite_h
+
+#include <vlib/vlib.h>
+#include <vnet/l3_types.h>
+
+/* Consider using vector types for speed? */
+typedef uword vnet_rewrite_data_t;
+
+/**
+ * Flags associated with the rewrite/adjacency
+ */
+typedef enum vnet_rewrite_flags_t_
+{
+  /**
+   * This adjacency/interface has output features configured
+   */
+  VNET_REWRITE_HAS_FEATURES = (1 << 0),
+} __attribute__ ((packed)) vnet_rewrite_flags_t;
+
+/* *INDENT-OFF* */
+typedef CLIB_PACKED (struct {
+  /* Interface to mark re-written packets with. */
+  u32 sw_if_index;
+
+  /* Next node to feed after packet rewrite is done. */
+  u16 next_index;
+
+  /* Number of bytes in rewrite data. */
+  u16 data_bytes;
+
+  /* Max packet size layer 3 (MTU) for output interface.
+     Used for MTU check after packet rewrite. */
+  u16 max_l3_packet_bytes;
+
+  /* Data-plane flags on the adjacency/rewrite */
+  vnet_rewrite_flags_t flags;
+
+  /* When dynamically writing a multicast destination L2 addresss
+   * this is the offset from the IP address at which to write in the
+   * IP->MAC address translation.
+   */
+  u8 dst_mcast_offset;
+
+  /* The mask to apply to the lower 4 bytes of the IP address before ORing
+   * into the destinaiton MAC address */
+  u32 dst_mcast_mask;
+
+  /* Rewrite string starting at end and going backwards. */
+  u8 data[0];
+}) vnet_rewrite_header_t;
+/* *INDENT-ON* */
+
+/**
+ * At 16 bytes of rewrite herader we have enought space left for a IPv6
+ * (40 bytes) + LISP-GPE (8 bytes) in the cache line
+ */
+STATIC_ASSERT (sizeof (vnet_rewrite_header_t) <= 16,
+	       "Rewrite header too big");
+
+/*
+  Helper macro for declaring rewrite string w/ given max-size.
+
+  Typical usage:
+    typedef struct {
+      //
+      int a, b;
+
+      // Total adjacency is 64 bytes.
+      vnet_rewrite_declare(64 - 2*sizeof(int)) rw;
+    } my_adjacency_t;
+*/
+#define vnet_declare_rewrite(total_bytes)				\
+struct {								\
+  vnet_rewrite_header_t rewrite_header;  			        \
+									\
+  u8 rewrite_data[(total_bytes) - sizeof (vnet_rewrite_header_t)];	\
+}
+
+always_inline void
+vnet_rewrite_clear_data_internal (vnet_rewrite_header_t * rw, int max_size)
+{
+  /* Sanity check values carefully for this memset operation */
+  ASSERT ((max_size > 0) && (max_size < VLIB_BUFFER_PRE_DATA_SIZE));
+
+  rw->data_bytes = 0;
+  memset (rw->data, 0xfe, max_size);
+}
+
+always_inline void
+vnet_rewrite_set_data_internal (vnet_rewrite_header_t * rw,
+				int max_size, void *data, int data_bytes)
+{
+  /* Sanity check values carefully for this memset operation */
+  ASSERT ((max_size > 0) && (max_size < VLIB_BUFFER_PRE_DATA_SIZE));
+  ASSERT ((data_bytes >= 0) && (data_bytes < max_size));
+
+  rw->data_bytes = data_bytes;
+  clib_memcpy (rw->data + max_size - data_bytes, data, data_bytes);
+  memset (rw->data, 0xfe, max_size - data_bytes);
+}
+
+#define vnet_rewrite_set_data(rw,data,data_bytes)		\
+  vnet_rewrite_set_data_internal (&((rw).rewrite_header),	\
+				  sizeof ((rw).rewrite_data),	\
+				  (data),			\
+				  (data_bytes))
+
+always_inline void *
+vnet_rewrite_get_data_internal (vnet_rewrite_header_t * rw, int max_size)
+{
+  ASSERT (rw->data_bytes <= max_size);
+  return rw->data + max_size - rw->data_bytes;
+}
+
+#define vnet_rewrite_get_data(rw) \
+  vnet_rewrite_get_data_internal (&((rw).rewrite_header), sizeof ((rw).rewrite_data))
+
+always_inline void
+vnet_rewrite_copy_one (vnet_rewrite_data_t * p0, vnet_rewrite_data_t * rw0,
+		       int i)
+{
+  p0[-i] = rw0[-i];
+}
+
+void vnet_rewrite_copy_slow_path (vnet_rewrite_data_t * p0,
+				  vnet_rewrite_data_t * rw0,
+				  word n_left, uword most_likely_size);
+
+/* *INDENT-OFF* */
+typedef CLIB_PACKED (struct {
+  u64 a;
+  u32 b;
+  u16 c;
+}) eh_copy_t;
+/* *INDENT-ON* */
+
+always_inline void
+_vnet_rewrite_one_header (vnet_rewrite_header_t * h0,
+			  void *packet0, int max_size, int most_likely_size)
+{
+  vnet_rewrite_data_t *p0 = packet0;
+  vnet_rewrite_data_t *rw0 = (vnet_rewrite_data_t *) (h0->data + max_size);
+  word n_left0;
+
+  /* 0xfefe => poisoned adjacency => crash */
+  ASSERT (h0->data_bytes != 0xfefe);
+
+  if (PREDICT_TRUE (h0->data_bytes == sizeof (eh_copy_t)))
+    {
+      eh_copy_t *s, *d;
+      s = (eh_copy_t *) (h0->data + max_size - sizeof (eh_copy_t));
+      d = (eh_copy_t *) (((u8 *) packet0) - sizeof (eh_copy_t));
+      clib_memcpy (d, s, sizeof (eh_copy_t));
+      return;
+    }
+
+
+#define _(i)								\
+  do {									\
+    if (most_likely_size > ((i)-1)*sizeof (vnet_rewrite_data_t))	\
+      vnet_rewrite_copy_one (p0, rw0, (i));				\
+  } while (0)
+
+  _(4);
+  _(3);
+  _(2);
+  _(1);
+
+#undef _
+
+  n_left0 = (int)
+    (((int) h0->data_bytes - most_likely_size) + (sizeof (rw0[0]) - 1))
+    / (int) sizeof (rw0[0]);
+  if (PREDICT_FALSE (n_left0 > 0))
+    vnet_rewrite_copy_slow_path (p0, rw0, n_left0, most_likely_size);
+}
+
+always_inline void
+_vnet_rewrite_two_headers (vnet_rewrite_header_t * h0,
+			   vnet_rewrite_header_t * h1,
+			   void *packet0,
+			   void *packet1, int max_size, int most_likely_size)
+{
+  vnet_rewrite_data_t *p0 = packet0;
+  vnet_rewrite_data_t *p1 = packet1;
+  vnet_rewrite_data_t *rw0 = (vnet_rewrite_data_t *) (h0->data + max_size);
+  vnet_rewrite_data_t *rw1 = (vnet_rewrite_data_t *) (h1->data + max_size);
+  word n_left0, n_left1;
+  int slow_path;
+
+  /* 0xfefe => poisoned adjacency => crash */
+  ASSERT (h0->data_bytes != 0xfefe);
+  ASSERT (h1->data_bytes != 0xfefe);
+
+  /* Arithmetic calculation: bytes0 == bytes1 == 14 */
+  slow_path = h0->data_bytes ^ h1->data_bytes;
+  slow_path += h0->data_bytes ^ sizeof (eh_copy_t);
+
+  if (PREDICT_TRUE (slow_path == 0))
+    {
+      eh_copy_t *s0, *d0, *s1, *d1;
+      s0 = (eh_copy_t *) (h0->data + max_size - sizeof (eh_copy_t));
+      d0 = (eh_copy_t *) (((u8 *) packet0) - sizeof (eh_copy_t));
+      clib_memcpy (d0, s0, sizeof (eh_copy_t));
+      s1 = (eh_copy_t *) (h1->data + max_size - sizeof (eh_copy_t));
+      d1 = (eh_copy_t *) (((u8 *) packet1) - sizeof (eh_copy_t));
+      clib_memcpy (d1, s1, sizeof (eh_copy_t));
+      return;
+    }
+
+#define _(i)								\
+  do {									\
+    if (most_likely_size > ((i)-1)*sizeof (vnet_rewrite_data_t))	\
+      {									\
+	vnet_rewrite_copy_one (p0, rw0, (i));				\
+	vnet_rewrite_copy_one (p1, rw1, (i));				\
+      }									\
+  } while (0)
+
+  _(4);
+  _(3);
+  _(2);
+  _(1);
+
+#undef _
+
+  n_left0 = (int)
+    (((int) h0->data_bytes - most_likely_size) + (sizeof (rw0[0]) - 1))
+    / (int) sizeof (rw0[0]);
+  n_left1 = (int)
+    (((int) h1->data_bytes - most_likely_size) + (sizeof (rw1[0]) - 1))
+    / (int) sizeof (rw1[0]);
+
+  if (PREDICT_FALSE (n_left0 > 0 || n_left1 > 0))
+    {
+      vnet_rewrite_copy_slow_path (p0, rw0, n_left0, most_likely_size);
+      vnet_rewrite_copy_slow_path (p1, rw1, n_left1, most_likely_size);
+    }
+}
+
+#define vnet_rewrite_one_header(rw0,p0,most_likely_size)	\
+  _vnet_rewrite_one_header (&((rw0).rewrite_header), (p0),	\
+			    sizeof ((rw0).rewrite_data),	\
+			    (most_likely_size))
+
+#define vnet_rewrite_two_headers(rw0,rw1,p0,p1,most_likely_size)	\
+  _vnet_rewrite_two_headers (&((rw0).rewrite_header), &((rw1).rewrite_header), \
+			     (p0), (p1),				\
+			     sizeof ((rw0).rewrite_data),		\
+			     (most_likely_size))
+
+always_inline void
+_vnet_fixup_one_header (vnet_rewrite_header_t * h0,
+			u8 * addr, u32 addr_len, u8 * packet0)
+{
+  if (PREDICT_TRUE (h0->dst_mcast_mask))
+    {
+      /* location to write to in the packet */
+      u8 *p0 = packet0 - h0->dst_mcast_offset;
+      u32 *p1 = (u32 *) p0;
+      /* location to copy from in the L3 dest address */
+      u32 *a0 = (u32 *) (addr + addr_len - sizeof (h0->dst_mcast_mask));
+
+      *p1 |= (*a0 & h0->dst_mcast_mask);
+    }
+}
+
+#define vnet_fixup_one_header(rw0,addr,p0)              \
+  _vnet_fixup_one_header (&((rw0).rewrite_header),                      \
+                          (u8*)(addr), sizeof((*addr)),                 \
+                          (u8*)(p0))
+
+#define VNET_REWRITE_FOR_SW_INTERFACE_ADDRESS_BROADCAST ((void *) 0)
+/** Deprecated */
+void vnet_rewrite_for_sw_interface (struct vnet_main_t *vnm,
+				    vnet_link_t packet_type,
+				    u32 sw_if_index,
+				    u32 node_index,
+				    void *dst_address,
+				    vnet_rewrite_header_t * rw,
+				    u32 max_rewrite_bytes);
+
+u32 vnet_tx_node_index_for_sw_interface (struct vnet_main_t *vnm,
+					 u32 sw_if_index);
+
+void vnet_rewrite_init (struct vnet_main_t *vnm,
+			u32 sw_if_index,
+			u32 this_node,
+			u32 next_node, vnet_rewrite_header_t * rw);
+
+u8 *vnet_build_rewrite_for_sw_interface (struct vnet_main_t *vnm,
+					 u32 sw_if_index,
+					 vnet_link_t packet_type,
+					 const void *dst_address);
+void vnet_update_adjacency_for_sw_interface (struct vnet_main_t *vnm,
+					     u32 sw_if_index, u32 ai);
+
+format_function_t format_vnet_rewrite;
+
+serialize_function_t serialize_vnet_rewrite, unserialize_vnet_rewrite;
+
+#endif /* included_vnet_rewrite_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */