Add native NETMAP driver

This is first drop of native NETMAP driver.
It is mainly tested with NETMAP pipes but also
support for native interfaces should work.

New CLI:
create netmap [<intf name>|valeXXX:YYY] [hw-addr <mac>] [pipe]
[master|slave]

Following example creates NETMAP pipe where VPP acts as master:

 create netmap name vale00:vpp1 pipe master

then NETMAP pkt-gen tool can be used to send traffic:

 pkt-gen -i vale00:vpp1}0  -f tx

Change-Id: Ie0ddaa5facc75285b78467420e8a9f9c8dfc39e5
Signed-off-by: Damjan Marion <damarion@cisco.com>

1 files changed, 284 insertions, 0 deletions

diff --git a/vnet/vnet/devices/netmap/node.c b/vnet/vnet/devices/netmap/node.c
new file mode 100644
index 00000000000..f866a282cfb
--- /dev/null
+++ b/vnet/vnet/devices/netmap/node.c
@@ -0,0 +1,284 @@
+/*
+ *------------------------------------------------------------------
+ * Copyright (c) 2016 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.
+ *------------------------------------------------------------------
+ */
+
+#include <vlib/vlib.h>
+#include <vlib/unix/unix.h>
+#include <vnet/ethernet/ethernet.h>
+
+#include <vnet/devices/netmap/netmap.h>
+
+#define foreach_netmap_input_error
+
+typedef enum {
+#define _(f,s) NETMAP_INPUT_ERROR_##f,
+  foreach_netmap_input_error
+#undef _
+  NETMAP_INPUT_N_ERROR,
+} netmap_input_error_t;
+
+static char * netmap_input_error_strings[] = {
+#define _(n,s) s,
+    foreach_netmap_input_error
+#undef _
+};
+
+enum {
+  NETMAP_INPUT_NEXT_DROP,
+  NETMAP_INPUT_NEXT_ETHERNET_INPUT,
+  NETMAP_INPUT_N_NEXT,
+};
+
+typedef struct {
+  u32 next_index;
+  u32 hw_if_index;
+  struct netmap_slot slot;
+} netmap_input_trace_t;
+
+static u8 * format_netmap_input_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  netmap_input_trace_t * t = va_arg (*args, netmap_input_trace_t *);
+  uword indent = format_get_indent (s);
+
+  s = format (s, "netmap: hw_if_index %d next-index %d",
+	      t->hw_if_index, t->next_index);
+  s = format (s, "\n%Uslot: flags 0x%x len %u buf_idx %u",
+	      format_white_space, indent + 2,
+	      t->slot.flags, t->slot.len, t->slot.buf_idx);
+  return s;
+}
+
+always_inline void
+buffer_add_to_chain(vlib_main_t *vm, u32 bi, u32 first_bi, u32 prev_bi)
+{
+  vlib_buffer_t * b = vlib_get_buffer (vm, bi);
+  vlib_buffer_t * first_b = vlib_get_buffer (vm, first_bi);
+  vlib_buffer_t * prev_b = vlib_get_buffer (vm, prev_bi);
+
+  /* update first buffer */
+  first_b->total_length_not_including_first_buffer +=  b->current_length;
+
+  /* update previous buffer */
+  prev_b->next_buffer = bi;
+  prev_b->flags |= VLIB_BUFFER_NEXT_PRESENT;
+
+  /* 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
+netmap_device_input_fn  (vlib_main_t * vm, vlib_node_runtime_t * node,
+			    vlib_frame_t * frame, u32 device_idx)
+{
+  u32 next_index = NETMAP_INPUT_NEXT_ETHERNET_INPUT;
+  uword n_trace = vlib_get_trace_count (vm, node);
+  netmap_main_t * nm = &netmap_main;
+  netmap_if_t * nif = pool_elt_at_index(nm->interfaces, device_idx);
+  u32 n_rx_packets = 0;
+  u32 n_rx_bytes = 0;
+  u32 * to_next = 0;
+  u32 n_free_bufs;
+  struct netmap_ring * ring;
+  int cur_ring;
+  u32 n_buffer_bytes = vlib_buffer_free_list_buffer_size (vm,
+    VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX);
+
+  if (nif->per_interface_next_index != ~0)
+      next_index = nif->per_interface_next_index;
+
+  n_free_bufs = vec_len (nm->rx_buffers);
+  if (PREDICT_FALSE(n_free_bufs < VLIB_FRAME_SIZE))
+    {
+      vec_validate(nm->rx_buffers, VLIB_FRAME_SIZE + n_free_bufs - 1);
+      n_free_bufs += vlib_buffer_alloc(vm, &nm->rx_buffers[n_free_bufs], VLIB_FRAME_SIZE);
+      _vec_len (nm->rx_buffers) = n_free_bufs;
+    }
+
+  cur_ring = nif->first_rx_ring;
+  while (cur_ring <= nif->last_rx_ring && n_free_bufs)
+    {
+      int r = 0;
+      u32 cur_slot_index;
+      ring = NETMAP_RXRING(nif->nifp, cur_ring);
+      r = nm_ring_space(ring);
+
+      if (!r)
+	{
+	  cur_ring++;
+	  continue;
+	}
+
+      if (r > n_free_bufs)
+	r = n_free_bufs;
+
+      cur_slot_index = ring->cur;
+      while (r)
+	{
+          u32 n_left_to_next;
+          u32 next0 = next_index;
+          vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+	  while (r && n_left_to_next)
+	    {
+	      vlib_buffer_t * b0, * first_b0 = 0;
+	      u32 offset = 0;
+	      u32 bi0 = 0, first_bi0 = 0, prev_bi0;
+	      u32 next_slot_index = (cur_slot_index + 1) % ring->num_slots;
+	      u32 next2_slot_index = (cur_slot_index + 2) % ring->num_slots;
+	      struct netmap_slot * slot = &ring->slot[cur_slot_index];
+	      u32 data_len = slot->len;
+
+	      /* prefetch 2 slots in advance */
+	      CLIB_PREFETCH (&ring->slot[next2_slot_index], CLIB_CACHE_LINE_BYTES, LOAD);
+	      /* prefetch start of next packet */
+	      CLIB_PREFETCH (NETMAP_BUF(ring, ring->slot[next_slot_index].buf_idx),
+			     CLIB_CACHE_LINE_BYTES, LOAD);
+
+	      while (data_len && n_free_bufs)
+		{
+		  /* grab free buffer */
+		  u32 last_empty_buffer = vec_len (nm->rx_buffers) - 1;
+		  prev_bi0 = bi0;
+		  bi0 = nm->rx_buffers[last_empty_buffer];
+		  b0 = vlib_get_buffer (vm, bi0);
+		  _vec_len (nm->rx_buffers) = last_empty_buffer;
+		  n_free_bufs--;
+
+		  /* copy data */
+		  u32 bytes_to_copy = data_len > n_buffer_bytes ? n_buffer_bytes : data_len;
+		  b0->current_data = 0;
+		  clib_memcpy (vlib_buffer_get_current (b0),
+			  (u8 *) NETMAP_BUF(ring, slot->buf_idx) + offset,
+			  bytes_to_copy);
+
+		  /* fill buffer header */
+		  b0->clone_count = 0;
+		  b0->current_length = bytes_to_copy;
+
+		  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] = nif->sw_if_index;
+		      vnet_buffer(b0)->sw_if_index[VLIB_TX] = (u32)~0;
+		      first_bi0 = bi0;
+		      first_b0 = vlib_get_buffer(vm, first_bi0);
+		    }
+		  else
+		    buffer_add_to_chain(vm, bi0, first_bi0, prev_bi0);
+
+		  offset += bytes_to_copy;
+		  data_len -= bytes_to_copy;
+		}
+
+	      /* trace */
+	      VLIB_BUFFER_TRACE_TRAJECTORY_INIT(first_b0);
+	      if (PREDICT_FALSE(n_trace > 0))
+	        {
+	          netmap_input_trace_t *tr;
+	          vlib_trace_buffer (vm, node, next0, first_b0, /* follow_chain */ 0);
+	          vlib_set_trace_count (vm, node, --n_trace);
+	          tr = vlib_add_trace (vm, node, first_b0, sizeof (*tr));
+	          tr->next_index = next0;
+		  tr->hw_if_index = nif->hw_if_index;
+		  memcpy (&tr->slot, slot, sizeof (struct netmap_slot));
+	        }
+	      /* enque and take next packet */
+	      vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+					       n_left_to_next, first_bi0, next0);
+
+	      /* next packet */
+	      n_rx_packets++;
+	      n_rx_bytes += slot->len;
+	      to_next[0] = first_bi0;
+	      to_next += 1;
+	      n_left_to_next--;
+	      cur_slot_index = next_slot_index;
+
+	      r--;
+	    }
+          vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+	}
+       ring->head = ring->cur = cur_slot_index;
+       cur_ring++;
+    }
+
+  if (n_rx_packets)
+    ioctl(nif->fd, NIOCTXSYNC, NULL);
+
+  vlib_increment_combined_counter
+    (vnet_get_main()->interface_main.combined_sw_if_counters
+     + VNET_INTERFACE_COUNTER_RX,
+     os_get_cpu_number(),
+     nif->hw_if_index,
+     n_rx_packets, n_rx_bytes);
+
+  return n_rx_packets;
+}
+
+static uword
+netmap_input_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+		    vlib_frame_t * frame)
+{
+  int i;
+  u32 n_rx_packets = 0;
+
+  netmap_main_t * nm = &netmap_main;
+
+  clib_bitmap_foreach (i, nm->pending_input_bitmap,
+    ({
+      clib_bitmap_set (nm->pending_input_bitmap, i, 0);
+      n_rx_packets += netmap_device_input_fn(vm, node, frame, i);
+    }));
+
+  return n_rx_packets;
+}
+
+
+VLIB_REGISTER_NODE (netmap_input_node) = {
+  .function = netmap_input_fn,
+  .name = "netmap-input",
+  .format_trace = format_netmap_input_trace,
+  .type = VLIB_NODE_TYPE_INPUT,
+  .state = VLIB_NODE_STATE_INTERRUPT,
+  .n_errors = NETMAP_INPUT_N_ERROR,
+  .error_strings = netmap_input_error_strings,
+
+  .n_next_nodes = NETMAP_INPUT_N_NEXT,
+  .next_nodes = {
+    [NETMAP_INPUT_NEXT_DROP] = "error-drop",
+    [NETMAP_INPUT_NEXT_ETHERNET_INPUT] = "ethernet-input",
+  },
+};
+