vnet/vnet/l2/feat_bitmap.c

   1 /*
   2  * feat_bitmap.c: bitmap for managing feature invocation
   3  *
   4  * Copyright (c) 2013 Cisco and/or its affiliates.
   5  * Licensed under the Apache License, Version 2.0 (the "License");
   6  * you may not use this file except in compliance with the License.
   7  * You may obtain a copy of the License at:
   8  *
   9  *     http://www.apache.org/licenses/LICENSE-2.0
  10  *
  11  * Unless required by applicable law or agreed to in writing, software
  12  * distributed under the License is distributed on an "AS IS" BASIS,
  13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14  * See the License for the specific language governing permissions and
  15  * limitations under the License.
  16  */
  17
  18 #include <vlib/vlib.h>
  19 #include <vnet/vnet.h>
  20 #include <vnet/pg/pg.h>
  21 #include <vnet/ethernet/ethernet.h>
  22 #include <vnet/ethernet/packet.h>
  23 #include <vlib/cli.h>
  24 #include <vnet/l2/l2_input.h>
  25 #include <vnet/l2/feat_bitmap.h>
  26
  27 #include <vppinfra/error.h>
  28 #include <vppinfra/hash.h>
  29 #include <vppinfra/cache.h>
  30
  31
  32 /*
  33  * Drop node for feature bitmaps
  34  * For features that just do a drop, or are not yet implemented.
  35  * Initial feature dispatch nodes don't need to set b0->error
  36  * in case of a possible drop because that will be done here.
  37  *The next node is always error-drop.
  38  */
  39
  40 static vlib_node_registration_t feat_bitmap_drop_node;
  41
  42 #define foreach_feat_bitmap_drop_error          \
  43 _(NO_FWD,     "L2 feature forwarding disabled") \
  44 _(NYI,        "L2 feature not implemented")
  45
  46 typedef enum
  47 {
  48 #define _(sym,str) FEAT_BITMAP_DROP_ERROR_##sym,
  49   foreach_feat_bitmap_drop_error
  50 #undef _
  51     FEAT_BITMAP_DROP_N_ERROR,
  52 } feat_bitmap_drop_error_t;
  53
  54 static char *feat_bitmap_drop_error_strings[] = {
  55 #define _(sym,string) string,
  56   foreach_feat_bitmap_drop_error
  57 #undef _
  58 };
  59
  60 typedef enum
  61 {
  62   FEAT_BITMAP_DROP_NEXT_DROP,
  63   FEAT_BITMAP_DROP_N_NEXT,
  64 } feat_bitmap_drop_next_t;
  65
  66 typedef struct
  67 {
  68   u32 feature_bitmap;
  69 } feat_bitmap_drop_trace_t;
  70
  71 /* packet trace format function */
  72 static u8 *
  73 format_feat_bitmap_drop_trace (u8 * s, va_list * args)
  74 {
  75   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  76   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  77   feat_bitmap_drop_trace_t *t = va_arg (*args, feat_bitmap_drop_trace_t *);
  78
  79   s =
  80     format (s, "feat_bitmap_drop: feature bitmap 0x%08x", t->feature_bitmap);
  81   return s;
  82 }
  83
  84 static uword
  85 feat_bitmap_drop_node_fn (vlib_main_t * vm,
  86                           vlib_node_runtime_t * node, vlib_frame_t * frame)
  87 {
  88   u32 n_left_from, *from, *to_next;
  89   feat_bitmap_drop_next_t next_index;
  90
  91   from = vlib_frame_vector_args (frame);
  92   n_left_from = frame->n_vectors;       /* number of packets to process */
  93   next_index = node->cached_next_index;
  94
  95   while (n_left_from > 0)
  96     {
  97       u32 n_left_to_next;
  98
  99       /* get space to enqueue frame to graph node "next_index" */
 100       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 101
 102       while (n_left_from > 0 && n_left_to_next > 0)
 103         {
 104           u32 bi0;
 105           vlib_buffer_t *b0;
 106           u32 next0;
 107
 108           /* speculatively enqueue b0 to the current next frame */
 109           bi0 = from[0];
 110           to_next[0] = bi0;
 111           from += 1;
 112           to_next += 1;
 113           n_left_from -= 1;
 114           n_left_to_next -= 1;
 115
 116           b0 = vlib_get_buffer (vm, bi0);
 117
 118           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 119                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 120             {
 121               feat_bitmap_drop_trace_t *t =
 122                 vlib_add_trace (vm, node, b0, sizeof (*t));
 123               t->feature_bitmap = vnet_buffer (b0)->l2.feature_bitmap;
 124             }
 125
 126           if (vnet_buffer (b0)->l2.feature_bitmap == 1)
 127             {
 128               /*
 129                * If we are executing the last feature, this is the
 130                * No forwarding catch-all
 131                */
 132               b0->error = node->errors[FEAT_BITMAP_DROP_ERROR_NO_FWD];
 133             }
 134           else
 135             {
 136               b0->error = node->errors[FEAT_BITMAP_DROP_ERROR_NYI];
 137             }
 138           next0 = FEAT_BITMAP_DROP_NEXT_DROP;
 139
 140           /* verify speculative enqueue, maybe switch current next frame */
 141           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 142                                            to_next, n_left_to_next,
 143                                            bi0, next0);
 144         }
 145
 146       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 147     }
 148   return frame->n_vectors;
 149 }
 150
 151 clib_error_t *
 152 feat_bitmap_drop_init (vlib_main_t * vm)
 153 {
 154   return 0;
 155 }
 156
 157 VLIB_INIT_FUNCTION (feat_bitmap_drop_init);
 158
 159 /* *INDENT-OFF* */
 160 VLIB_REGISTER_NODE (feat_bitmap_drop_node,static) = {
 161   .function = feat_bitmap_drop_node_fn,
 162   .name = "feature-bitmap-drop",
 163   .vector_size = sizeof (u32),
 164   .format_trace = format_feat_bitmap_drop_trace,
 165   .type = VLIB_NODE_TYPE_INTERNAL,
 166
 167   .n_errors = ARRAY_LEN(feat_bitmap_drop_error_strings),
 168   .error_strings = feat_bitmap_drop_error_strings,
 169
 170   .n_next_nodes = FEAT_BITMAP_DROP_N_NEXT,
 171
 172   /* edit / add dispositions here */
 173   .next_nodes = {
 174     [FEAT_BITMAP_DROP_NEXT_DROP]  = "error-drop",
 175   },
 176 };
 177 /* *INDENT-ON* */
 178
 179 /*
 180  * fd.io coding-style-patch-verification: ON
 181  *
 182  * Local Variables:
 183  * eval: (c-set-style "gnu")
 184  * End:
 185  */