Revert to [HICN-638] Check if systemd is running before enabling hicn-light service

Signed-off-by: Mauro Sardara <msardara@cisco.com>
Change-Id: I1810d96e001a4e6e097e1efa331b682af750925d

1 files changed, 214 insertions, 0 deletions

diff --git a/hicn-plugin/src/data_fwd.h b/hicn-plugin/src/data_fwd.h
new file mode 100644
index 000000000..d95f564c3
--- /dev/null
+++ b/hicn-plugin/src/data_fwd.h
@@ -0,0 +1,214 @@
+/*
+ * Copyright (c) 2017-2020 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.
+ */
+
+#ifndef __HICN_DATA_FWD_H__
+#define __HICN_DATA_FWD_H__
+
+#include <vlib/buffer.h>
+
+#include "pcs.h"
+
+/**
+ * @file data_fwd.h
+ *
+ * This is the node encoutered by data packets after the hicn-data-pcslookup.
+ * This node has two goals: 1) clone/copy the vlib buffer as many time as the number
+ * of faces stored in the pit entry, 2) store a clone/copy of the vlib buffer in the CS.
+ * Unless there are memory issue (no more vlib buffer available to perform cloning/copy),
+ * a single vlib buffer received might results in several vlib buffer sent to the next
+ * vlib node (hicn4-iface-output or hicn6-iface-output).
+ *
+ * It must be noted that cloning is possible only if the lentgh of the data pointed by
+ * the vlib buffer is at least 256 bytes. This is due to an imposition in the vpp source
+ * code. In all the other cases the vlib buffer is copied. Cloning is performed by advancing
+ * the vlib buffer of 256 bytes and a new vlib buffer is created and chained in from of the received
+ * buffer. Additionally, the 256 bytes removed (advanced) from the received vlib buffer are
+ * copied in the head vlib buffer. In case of multiple cloning for the same vlib buffer, this
+ * mechanism allows us to have a different hICN header for each clone (+ the same additional bytes
+ * due to the vpp restriction on cloning).
+ */
+
+
+/* Trace context struct */
+typedef struct
+{
+  u32 next_index;
+  u32 sw_if_index;
+  u8 pkt_type;
+  u8 packet_data[64];
+} hicn_data_fwd_trace_t;
+
+typedef enum
+{
+  HICN_DATA_FWD_NEXT_V4_LOOKUP,
+  HICN_DATA_FWD_NEXT_V6_LOOKUP,
+  HICN_DATA_FWD_NEXT_IFACE4_OUT,
+  HICN_DATA_FWD_NEXT_IFACE6_OUT,
+  HICN_DATA_FWD_NEXT_ERROR_DROP,
+  HICN_DATA_FWD_N_NEXT,
+} hicn_data_fwd_next_t;
+
+/**
+ * @brief Create a maximum of 256 clones of buffer and store them
+ *   in the supplied array. Unlike the original function in the vlib
+ *   library, we don't prevent cloning if n_buffer==1 and if
+ *   s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2.
+ *
+ * @param vm - (vlib_main_t *) vlib main data structure pointer
+ * @param src_buffer - (u32) source buffer index
+ * @param buffers - (u32 * ) buffer index array
+ * @param n_buffers - (u16) number of buffer clones requested (<=256)
+ * @param head_end_offset - (u16) offset relative to current position
+ *          where packet head ends
+ * @return - (u16) number of buffers actually cloned, may be
+ *   less than the number requested or zero
+ */
+always_inline u16
+vlib_buffer_clone_256_2 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
+			 u16 n_buffers, u16 head_end_offset)
+{
+  u16 i;
+  vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
+
+  ASSERT (n_buffers);
+  ASSERT (n_buffers <= 256);
+
+  if (s->current_length <= head_end_offset + CLIB_CACHE_LINE_BYTES * 2)
+    {
+      for (i = 0; i < n_buffers; i++)
+	{
+	  vlib_buffer_t *d;
+	  d = vlib_buffer_copy (vm, s);
+	  if (d == 0)
+	    return i;
+	  buffers[i] = vlib_get_buffer_index (vm, d);
+	}
+      return n_buffers;
+    }
+  n_buffers = vlib_buffer_alloc_from_pool (vm, buffers, n_buffers,
+					   s->buffer_pool_index);
+
+  for (i = 0; i < n_buffers; i++)
+    {
+      vlib_buffer_t *d = vlib_get_buffer (vm, buffers[i]);
+      d->current_data = s->current_data;
+      d->current_length = head_end_offset;
+      d->trace_handle = s->trace_handle;
+
+      d->total_length_not_including_first_buffer = s->current_length -
+	head_end_offset;
+      if (PREDICT_FALSE (s->flags & VLIB_BUFFER_NEXT_PRESENT))
+	{
+	  d->total_length_not_including_first_buffer +=
+	    s->total_length_not_including_first_buffer;
+	}
+      d->flags = s->flags | VLIB_BUFFER_NEXT_PRESENT;
+      d->flags &= ~VLIB_BUFFER_EXT_HDR_VALID;
+      d->trace_handle = s->trace_handle;
+      clib_memcpy_fast (d->opaque, s->opaque, sizeof (s->opaque));
+      clib_memcpy_fast (d->opaque2, s->opaque2, sizeof (s->opaque2));
+      clib_memcpy_fast (vlib_buffer_get_current (d),
+			vlib_buffer_get_current (s), head_end_offset);
+      d->next_buffer = src_buffer;
+    }
+  vlib_buffer_advance (s, head_end_offset);
+  s->ref_count = n_buffers;
+  while (s->flags & VLIB_BUFFER_NEXT_PRESENT)
+    {
+      s = vlib_get_buffer (vm, s->next_buffer);
+      s->ref_count = n_buffers;
+    }
+
+  return n_buffers;
+}
+
+/**
+ * @brief Create multiple clones of buffer and store them
+ *  in the supplied array. Unlike the function in the vlib library,
+ *   we allow src_buffer to have ref_count != 0.
+ *
+ * @param vm - (vlib_main_t *) vlib main data structure pointer
+ * @param src_buffer - (u32) source buffer index
+ * @param buffers - (u32 * ) buffer index array
+ * @param n_buffers - (u16) number of buffer clones requested (<=256)
+ * @param head_end_offset - (u16) offset relative to current position
+ *   where packet head ends
+ * @return - (u16) number of buffers actually cloned, may be
+ *   less than the number requested or zero
+ */
+always_inline u16
+vlib_buffer_clone2 (vlib_main_t * vm, u32 src_buffer, u32 * buffers,
+		    u16 n_buffers, u16 head_end_offset)
+{
+  vlib_buffer_t *s = vlib_get_buffer (vm, src_buffer);
+
+  /*
+   * total_length_not_including_first_buffer is not initialized to 0
+   * when a buffer is used.
+   */
+  if (PREDICT_TRUE (s->next_buffer == 0))
+    s->total_length_not_including_first_buffer = 0;
+
+  u16 n_cloned = 0;
+  u8 n_clone_src = 255 - s->ref_count;
+
+  /*
+   * We need to copy src for all the clones that cannot be chained in
+   * the src_buffer
+   */
+  /* MAX(ref_count) = 256 */
+  if (n_buffers > n_clone_src)
+    {
+      vlib_buffer_t *copy;
+      /* Ok to call the original vlib_buffer_copy. */
+      copy = vlib_buffer_copy (vm, s);
+      n_cloned += vlib_buffer_clone (vm,
+				     vlib_get_buffer_index (vm, copy),
+				     buffers,
+				     n_buffers - n_clone_src,
+				     head_end_offset);
+      n_buffers -= n_cloned;
+    }
+  /*
+   * vlib_buffer_clone_256 check if ref_count is 0. We force it to be
+   * 0 before calling the function and we retore it to the right value
+   * after the function has been called
+   */
+  u8 tmp_ref_count = s->ref_count;
+
+  s->ref_count = 1;
+  /*
+   * The regular vlib_buffer_clone_256 does copy if we need to clone
+   * only one packet. While this is not a problem per se, it adds
+   * complexity to the code, especially because we need to add 1 to
+   * ref_count when the packet is cloned.
+   */
+  n_cloned += vlib_buffer_clone_256_2 (vm,
+				       src_buffer,
+				       (buffers + n_cloned),
+				       n_buffers, head_end_offset);
+
+  s->ref_count += (tmp_ref_count - 1);
+
+  return n_cloned;
+}
+
+#endif /* //__HICN_DATA_FWD_H__ */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables: eval: (c-set-style "gnu") End:
+ */