lcp_adj.c

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/*
 * Copyright (c) 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.
 */

#include <vnet/adj/adj_delegate.h>
#include <linux-cp/lcp_adj.h>

#include <vppinfra/bihash_32_8.h>
#include <vppinfra/bihash_template.c>

static adj_delegate_type_t adj_type;
static lcp_adj_key_t *adj_keys;

/**
 * The table of adjacencies indexed by the rewrite string
 */
BVT (clib_bihash) lcp_adj_tbl;

static_always_inline void
lcp_adj_mk_key_adj (const ip_adjacency_t *adj, lcp_adj_key_t *key)
{
  lcp_adj_mk_key (adj->rewrite_header.data, adj->rewrite_header.data_bytes,
                  adj->rewrite_header.sw_if_index, key);
}

static u8 *
lcp_adj_delegate_format (const adj_delegate_t *aed, u8 *s)
{
  return (format (s, "lcp"));
}

static void
lcp_adj_delegate_adj_deleted (adj_delegate_t *aed)
{
  ip_adjacency_t *adj;
  lcp_adj_kv_t kv;

  adj = adj_get (aed->ad_adj_index);

  lcp_adj_mk_key_adj (adj, &kv.k);

  BV (clib_bihash_add_del) (&lcp_adj_tbl, &kv.kv, 0);

  if (aed->ad_index != INDEX_INVALID)
    pool_put_index (adj_keys, aed->ad_index);
}

/* when an adj is modified:
 *
 * An existing hash entry may need to be deleted. This may occur when:
 * * The newly modified adj does not have IP_LOOKUP_NEXT_REWRITE as next idx
 * * The rewrite (== major component of hash key) changed
 *
 * A new hash entry may need to be added. This may occur when:
 * * The newly modified adj has IP_LOOKUP_NEXT_REWRITE as next idx
 * * The rewrite changed or there was no existing hash entry
 */
static void
lcp_adj_delegate_adj_modified (adj_delegate_t *aed)
{
  ip_adjacency_t *adj;
  lcp_adj_kv_t kv;
  lcp_adj_key_t *adj_key = NULL;
  u8 save_adj, key_changed;

  key_changed = 0;

  adj = adj_get (aed->ad_adj_index);
  save_adj = (IP_LOOKUP_NEXT_REWRITE == adj->lookup_next_index);

  if (aed->ad_index != INDEX_INVALID)
    adj_key = pool_elt_at_index (adj_keys, aed->ad_index);

  /* return if there was no stored adj and we will not add one */
  if (!adj_key && !save_adj)
    return;

  /* build kv if a new entry should be stored */
  if (save_adj)
    {
      lcp_adj_mk_key_adj (adj, &kv.k);
      kv.v = aed->ad_adj_index;
      if (adj_key)
        key_changed = (clib_memcmp (adj_key, &kv.k, sizeof (*adj_key)) != 0);
    }

  /* delete old entry if needed */
  if (adj_key && ((save_adj && key_changed) || (!save_adj)))
    {
      lcp_adj_kv_t old_kv;

      clib_memcpy_fast (&old_kv.k, adj_key, sizeof (*adj_key));
      old_kv.v = 0;

      BV (clib_bihash_add_del) (&lcp_adj_tbl, &old_kv.kv, 0);

      if (!save_adj)
        {
          pool_put (adj_keys, adj_key);
          aed->ad_index = INDEX_INVALID;
        }
    }

  /* add new entry if needed */
  if (save_adj)
    {
      BV (clib_bihash_add_del) (&lcp_adj_tbl, &kv.kv, 1);

      if (!adj_key)
        {
          pool_get (adj_keys, adj_key);
          aed->ad_index = adj_key - adj_keys;
        }
      clib_memcpy_fast (adj_key, &kv.k, sizeof (*adj_key));
    }
}

static void
lcp_adj_delegate_adj_created (adj_index_t ai)
{
  ip_adjacency_t *adj;
  lcp_adj_kv_t kv;
  index_t lai = INDEX_INVALID;
  lcp_adj_key_t *adj_key;

  adj = adj_get (ai);

  if (IP_LOOKUP_NEXT_REWRITE == adj->lookup_next_index)
    {
      lcp_adj_mk_key_adj (adj, &kv.k);
      pool_get (adj_keys, adj_key);
      clib_memcpy_fast (adj_key, &kv.k, sizeof (*adj_key));
      kv.v = ai;

      BV (clib_bihash_add_del) (&lcp_adj_tbl, &kv.kv, 1);
      lai = adj_key - adj_keys;
    }

  adj_delegate_add (adj, adj_type, lai);
}

u8 *
format_lcp_adj_kvp (u8 *s, va_list *args)
{
  BVT (clib_bihash_kv) *kv = va_arg (*args, BVT (clib_bihash_kv) *);
  CLIB_UNUSED (int verbose) = va_arg (*args, int);
  lcp_adj_kv_t *akv = (lcp_adj_kv_t *) kv;

  s = format (s, "  %U:%U\n    %U", format_vnet_sw_if_index_name,
              vnet_get_main (), akv->k.sw_if_index, format_hex_bytes,
              akv->k.rewrite, 18, format_adj_nbr, akv->v, 4);

  return (s);
}

static clib_error_t *
lcp_adj_show_cmd (vlib_main_t *vm, unformat_input_t *input,
                  vlib_cli_command_t *cmd)
{
  u8 verbose = 0;

  if (unformat (input, "verbose"))
    verbose = 1;

  vlib_cli_output (vm, "Linux-CP Adjs:\n%U", BV (format_bihash), &lcp_adj_tbl,
                   verbose);

  return 0;
}

VLIB_CLI_COMMAND (lcp_itf_pair_show_cmd_node, static) = {
  .path = "show lcp adj",
  .function = lcp_adj_show_cmd,
  .short_help = "show lcp adj",
  .is_mp_safe = 1,
};

const adj_delegate_vft_t lcp_adj_vft = {
  .adv_format = lcp_adj_delegate_format,
  .adv_adj_deleted = lcp_adj_delegate_adj_deleted,
  .adv_adj_modified = lcp_adj_delegate_adj_modified,
  .adv_adj_created = lcp_adj_delegate_adj_created,
};

static clib_error_t *
lcp_adj_init (vlib_main_t *vm)
{
  adj_type = adj_delegate_register_new_type (&lcp_adj_vft);

  BV (clib_bihash_init) (&lcp_adj_tbl, "linux-cp ADJ table", 1024, 1 << 24);
  BV (clib_bihash_set_kvp_format_fn) (&lcp_adj_tbl, format_lcp_adj_kvp);

  return (NULL);
}

VLIB_INIT_FUNCTION (lcp_adj_init);

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */