src/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/ethernet/ethernet.h>
  21 #include <vnet/ethernet/packet.h>
  22 #include <vlib/cli.h>
  23 #include <vnet/l2/l2_input.h>
  24 #include <vnet/l2/feat_bitmap.h>
  25
  26 #include <vppinfra/error.h>
  27 #include <vppinfra/hash.h>
  28 #include <vppinfra/cache.h>
  29
  30
  31 /*
  32  * Drop node for feature bitmaps
  33  * For features that just do a drop, or are not yet implemented.
  34  * Initial feature dispatch nodes don't need to set b0->error
  35  * in case of a possible drop because that will be done here.
  36  *The next node is always error-drop.
  37  */
  38
  39 static vlib_node_registration_t feat_bitmap_drop_node;
  40
  41 #define foreach_feat_bitmap_drop_error          \
  42 _(NO_FWD,     "L2 feature forwarding disabled") \
  43 _(NYI,        "L2 feature not implemented")
  44
  45 typedef enum
  46 {
  47 #define _(sym,str) FEAT_BITMAP_DROP_ERROR_##sym,
  48   foreach_feat_bitmap_drop_error
  49 #undef _
  50     FEAT_BITMAP_DROP_N_ERROR,
  51 } feat_bitmap_drop_error_t;
  52
  53 static char *feat_bitmap_drop_error_strings[] = {
  54 #define _(sym,string) string,
  55   foreach_feat_bitmap_drop_error
  56 #undef _
  57 };
  58
  59 typedef enum
  60 {
  61   FEAT_BITMAP_DROP_NEXT_DROP,
  62   FEAT_BITMAP_DROP_N_NEXT,
  63 } feat_bitmap_drop_next_t;
  64
  65 typedef struct
  66 {
  67   u32 feature_bitmap;
  68 } feat_bitmap_drop_trace_t;
  69
  70 /* packet trace format function */
  71 static u8 *
  72 format_feat_bitmap_drop_trace (u8 * s, va_list * args)
  73 {
  74   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
  75   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
  76   feat_bitmap_drop_trace_t *t = va_arg (*args, feat_bitmap_drop_trace_t *);
  77
  78   s =
  79     format (s, "feat_bitmap_drop: feature bitmap 0x%08x", t->feature_bitmap);
  80   return s;
  81 }
  82
  83 static uword
  84 feat_bitmap_drop_node_fn (vlib_main_t * vm,
  85                           vlib_node_runtime_t * node, vlib_frame_t * frame)
  86 {
  87   u32 n_left_from, *from, *to_next;
  88   feat_bitmap_drop_next_t next_index;
  89
  90   from = vlib_frame_vector_args (frame);
  91   n_left_from = frame->n_vectors;       /* number of packets to process */
  92   next_index = node->cached_next_index;
  93
  94   while (n_left_from > 0)
  95     {
  96       u32 n_left_to_next;
  97
  98       /* get space to enqueue frame to graph node "next_index" */
  99       vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
 100
 101       while (n_left_from > 0 && n_left_to_next > 0)
 102         {
 103           u32 bi0;
 104           vlib_buffer_t *b0;
 105           u32 next0;
 106
 107           /* speculatively enqueue b0 to the current next frame */
 108           bi0 = from[0];
 109           to_next[0] = bi0;
 110           from += 1;
 111           to_next += 1;
 112           n_left_from -= 1;
 113           n_left_to_next -= 1;
 114
 115           b0 = vlib_get_buffer (vm, bi0);
 116
 117           if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)
 118                              && (b0->flags & VLIB_BUFFER_IS_TRACED)))
 119             {
 120               feat_bitmap_drop_trace_t *t =
 121                 vlib_add_trace (vm, node, b0, sizeof (*t));
 122               t->feature_bitmap = vnet_buffer (b0)->l2.feature_bitmap;
 123             }
 124
 125           if (vnet_buffer (b0)->l2.feature_bitmap == 1)
 126             {
 127               /*
 128                * If we are executing the last feature, this is the
 129                * No forwarding catch-all
 130                */
 131               b0->error = node->errors[FEAT_BITMAP_DROP_ERROR_NO_FWD];
 132             }
 133           else
 134             {
 135               b0->error = node->errors[FEAT_BITMAP_DROP_ERROR_NYI];
 136             }
 137           next0 = FEAT_BITMAP_DROP_NEXT_DROP;
 138
 139           /* verify speculative enqueue, maybe switch current next frame */
 140           vlib_validate_buffer_enqueue_x1 (vm, node, next_index,
 141                                            to_next, n_left_to_next,
 142                                            bi0, next0);
 143         }
 144
 145       vlib_put_next_frame (vm, node, next_index, n_left_to_next);
 146     }
 147   return frame->n_vectors;
 148 }
 149
 150 clib_error_t *
 151 feat_bitmap_drop_init (vlib_main_t * vm)
 152 {
 153   return 0;
 154 }
 155
 156 VLIB_INIT_FUNCTION (feat_bitmap_drop_init);
 157
 158 /* *INDENT-OFF* */
 159 VLIB_REGISTER_NODE (feat_bitmap_drop_node,static) = {
 160   .function = feat_bitmap_drop_node_fn,
 161   .name = "feature-bitmap-drop",
 162   .vector_size = sizeof (u32),
 163   .format_trace = format_feat_bitmap_drop_trace,
 164   .type = VLIB_NODE_TYPE_INTERNAL,
 165
 166   .n_errors = ARRAY_LEN(feat_bitmap_drop_error_strings),
 167   .error_strings = feat_bitmap_drop_error_strings,
 168
 169   .n_next_nodes = FEAT_BITMAP_DROP_N_NEXT,
 170
 171   /* edit / add dispositions here */
 172   .next_nodes = {
 173     [FEAT_BITMAP_DROP_NEXT_DROP]  = "error-drop",
 174   },
 175 };
 176 /* *INDENT-ON* */
 177
 178 /*
 179  * fd.io coding-style-patch-verification: ON
 180  *
 181  * Local Variables:
 182  * eval: (c-set-style "gnu")
 183  * End:
 184  */