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Diffstat (limited to 'vnet/vnet/feature/registration.c')
| -rw-r--r-- | vnet/vnet/feature/registration.c | 301 |
1 files changed, 0 insertions, 301 deletions
diff --git a/vnet/vnet/feature/registration.c b/vnet/vnet/feature/registration.c deleted file mode 100644 index 1deeeef904c..00000000000 --- a/vnet/vnet/feature/registration.c +++ /dev/null @@ -1,301 +0,0 @@ -/* - * 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 <vnet/vnet.h> -#include <vnet/ip/ip.h> -#include <vnet/mpls/mpls.h> - -/** - * @file - * @brief Feature Subgraph Ordering. - - Dynamically compute feature subgraph ordering by performing a - topological sort across a set of "feature A before feature B" and - "feature C after feature B" constraints. - - Use the topological sort result to set up vnet_config_main_t's for - use at runtime. - - Feature subgraph arcs are simple enough. They start at specific - fixed nodes, and end at specific fixed nodes. In between, a - per-interface current feature configuration dictates which - additional nodes each packet visits. Each so-called feature node - can [of course] drop any specific packet. - - See ip4_forward.c, ip6_forward.c in this directory to see the - current rx-unicast, rx-multicast, and tx feature subgraph arc - definitions. - - Let's say that we wish to add a new feature to the ip4 unicast - feature subgraph arc, which needs to run before @c ip4-lookup. In - either base code or a plugin, - <CODE><PRE> - \#include <vnet/feature/feature.h> - </PRE></CODE> - - and add the new feature as shown: - - <CODE><PRE> - VNET_FEATURE_INIT (ip4_lookup, static) = - { - .arch_name = "ip4-unicast", - .node_name = "my-ip4-unicast-feature", - .runs_before = VLIB_FEATURES ("ip4-lookup") - }; - </PRE></CODE> - - Here's the standard coding pattern to enable / disable - @c my-ip4-unicast-feature on an interface: - - <CODE><PRE> - - sw_if_index = <interface-handle> - vnet_feature_enable_disable ("ip4-unicast", "my-ip4-unicast-feature", - sw_if_index, 1 ); - </PRE></CODE> - - Here's how to obtain the correct next node index in packet - processing code, aka in the implementation of @c my-ip4-unicast-feature: - - <CODE><PRE> - vnet_feature_next (sw_if_index0, &next0, b0); - - </PRE></CODE> - - Nodes are free to drop or otherwise redirect packets. Packets - which "pass" should be enqueued via the next0 arc computed by - vnet_feature_next. -*/ - - -static int -comma_split (u8 * s, u8 ** a, u8 ** b) -{ - *a = s; - - while (*s && *s != ',') - s++; - - if (*s == ',') - *s = 0; - else - return 1; - - *b = (u8 *) (s + 1); - return 0; -} - -/** - * @brief Initialize a feature graph arc - * @param vm vlib main structure pointer - * @param vcm vnet config main structure pointer - * @param feature_start_nodes names of start-nodes which use this - * feature graph arc - * @param num_feature_start_nodes number of start-nodes - * @param first_reg first element in - * [an __attribute__((constructor)) function built, or - * otherwise created] singly-linked list of feature registrations - * @param [out] in_feature_nodes returned vector of - * topologically-sorted feature node names, for use in - * show commands - * @returns 0 on success, otherwise an error message. Errors - * are fatal since they invariably involve mistyped node-names, or - * genuinely missing node-names - */ -clib_error_t * -vnet_feature_arc_init (vlib_main_t * vm, - vnet_config_main_t * vcm, - char **feature_start_nodes, - int num_feature_start_nodes, - vnet_feature_registration_t * first_reg, - char ***in_feature_nodes) -{ - uword *index_by_name; - uword *reg_by_index; - u8 **node_names = 0; - u8 *node_name; - char **these_constraints; - char *this_constraint_c; - u8 **constraints = 0; - u8 *constraint_tuple; - u8 *this_constraint; - u8 **orig, **closure; - uword *p; - int i, j, k; - u8 *a_name, *b_name; - int a_index, b_index; - int n_features; - u32 *result = 0; - vnet_feature_registration_t *this_reg = 0; - char **feature_nodes = 0; - hash_pair_t *hp; - u8 **keys_to_delete = 0; - - index_by_name = hash_create_string (0, sizeof (uword)); - reg_by_index = hash_create (0, sizeof (uword)); - - this_reg = first_reg; - - /* pass 1, collect feature node names, construct a before b pairs */ - while (this_reg) - { - node_name = format (0, "%s%c", this_reg->node_name, 0); - hash_set (reg_by_index, vec_len (node_names), (uword) this_reg); - - hash_set_mem (index_by_name, node_name, vec_len (node_names)); - - vec_add1 (node_names, node_name); - - these_constraints = this_reg->runs_before; - while (these_constraints && these_constraints[0]) - { - this_constraint_c = these_constraints[0]; - - constraint_tuple = format (0, "%s,%s%c", node_name, - this_constraint_c, 0); - vec_add1 (constraints, constraint_tuple); - these_constraints++; - } - - these_constraints = this_reg->runs_after; - while (these_constraints && these_constraints[0]) - { - this_constraint_c = these_constraints[0]; - - constraint_tuple = format (0, "%s,%s%c", - this_constraint_c, node_name, 0); - vec_add1 (constraints, constraint_tuple); - these_constraints++; - } - - this_reg = this_reg->next; - } - - n_features = vec_len (node_names); - orig = clib_ptclosure_alloc (n_features); - - for (i = 0; i < vec_len (constraints); i++) - { - this_constraint = constraints[i]; - - if (comma_split (this_constraint, &a_name, &b_name)) - return clib_error_return (0, "comma_split failed!"); - - p = hash_get_mem (index_by_name, a_name); - /* - * Note: the next two errors mean that something is - * b0rked. As in: if you code "A depends on B," and you forget - * to define a FEATURE_INIT macro for B, you lose. - * Nonexistent graph nodes are tolerated. - */ - if (p == 0) - return clib_error_return (0, "feature node '%s' not found", a_name); - a_index = p[0]; - - p = hash_get_mem (index_by_name, b_name); - if (p == 0) - return clib_error_return (0, "feature node '%s' not found", b_name); - b_index = p[0]; - - /* add a before b to the original set of constraints */ - orig[a_index][b_index] = 1; - vec_free (this_constraint); - } - - /* Compute the positive transitive closure of the original constraints */ - closure = clib_ptclosure (orig); - - /* Compute a partial order across feature nodes, if one exists. */ -again: - for (i = 0; i < n_features; i++) - { - for (j = 0; j < n_features; j++) - { - if (closure[i][j]) - goto item_constrained; - } - /* Item i can be output */ - vec_add1 (result, i); - { - for (k = 0; k < n_features; k++) - closure[k][i] = 0; - /* - * Add a "Magic" a before a constraint. - * This means we'll never output it again - */ - closure[i][i] = 1; - goto again; - } - item_constrained: - ; - } - - /* see if we got a partial order... */ - if (vec_len (result) != n_features) - return clib_error_return (0, "%d feature_init_cast no partial order!"); - - /* - * We win. - * Bind the index variables, and output the feature node name vector - * using the partial order we just computed. Result is in stack - * order, because the entry with the fewest constraints (e.g. none) - * is output first, etc. - */ - - for (i = n_features - 1; i >= 0; i--) - { - p = hash_get (reg_by_index, result[i]); - ASSERT (p != 0); - this_reg = (vnet_feature_registration_t *) p[0]; - if (this_reg->feature_index_ptr) - *this_reg->feature_index_ptr = n_features - (i + 1); - this_reg->feature_index = n_features - (i + 1); - vec_add1 (feature_nodes, this_reg->node_name); - } - - /* Set up the config infrastructure */ - vnet_config_init (vm, vcm, - feature_start_nodes, - num_feature_start_nodes, - feature_nodes, vec_len (feature_nodes)); - - /* Save a copy for show command */ - *in_feature_nodes = feature_nodes; - - /* Finally, clean up all the shit we allocated */ - /* *INDENT-OFF* */ - hash_foreach_pair (hp, index_by_name, - ({ - vec_add1 (keys_to_delete, (u8 *)hp->key); - })); - /* *INDENT-ON* */ - hash_free (index_by_name); - for (i = 0; i < vec_len (keys_to_delete); i++) - vec_free (keys_to_delete[i]); - vec_free (keys_to_delete); - hash_free (reg_by_index); - vec_free (result); - clib_ptclosure_free (orig); - clib_ptclosure_free (closure); - return 0; -} - -/* - * fd.io coding-style-patch-verification: ON - * - * Local Variables: - * eval: (c-set-style "gnu") - * End: - */ |