Neale Ranns | 1f50bf8 | 2019-07-16 15:28:52 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (c) 2019 Cisco and/or its affiliates. |
| 3 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 4 | * you may not use this file except in compliance with the License. |
| 5 | * You may obtain a copy of the License at: |
| 6 | * |
| 7 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 8 | * |
| 9 | * Unless required by applicable law or agreed to in writing, software |
| 10 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 11 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 12 | * See the License for the specific language governing permissions and |
| 13 | * limitations under the License. |
| 14 | */ |
| 15 | |
| 16 | #include <vnet/fib/fib_entry_track.h> |
| 17 | #include <vnet/fib/fib_table.h> |
| 18 | #include <vnet/fib/fib_entry_delegate.h> |
| 19 | #include <vnet/fib/fib_walk.h> |
| 20 | |
| 21 | static fib_entry_delegate_t * |
| 22 | fib_entry_track_delegate_add (u32 fib_index, |
| 23 | const fib_prefix_t *prefix) |
| 24 | { |
| 25 | fib_entry_delegate_t *fed; |
| 26 | fib_node_index_t fei; |
| 27 | |
| 28 | fei = fib_table_entry_special_add(fib_index, |
| 29 | prefix, |
| 30 | FIB_SOURCE_RR, |
| 31 | FIB_ENTRY_FLAG_NONE); |
| 32 | |
| 33 | fed = fib_entry_delegate_find_or_add(fib_entry_get(fei), |
| 34 | FIB_ENTRY_DELEGATE_TRACK); |
| 35 | |
| 36 | fib_node_init(&fed->fd_track.fedt_node, |
| 37 | FIB_NODE_TYPE_ENTRY_TRACK); |
| 38 | |
| 39 | fed->fd_entry_index = fei; |
| 40 | fed->fd_track.fedt_sibling = |
| 41 | fib_entry_child_add(fei, |
| 42 | FIB_NODE_TYPE_ENTRY_TRACK, |
| 43 | fib_entry_delegate_get_index(fed)); |
| 44 | |
| 45 | return (fed); |
| 46 | } |
| 47 | |
| 48 | fib_node_index_t |
| 49 | fib_entry_track (u32 fib_index, |
| 50 | const fib_prefix_t *prefix, |
| 51 | fib_node_type_t child_type, |
| 52 | index_t child_index, |
| 53 | u32 *sibling) |
| 54 | { |
| 55 | fib_entry_delegate_t *fed; |
| 56 | fib_node_index_t fei; |
| 57 | |
| 58 | fei = fib_table_lookup_exact_match(fib_index, prefix); |
| 59 | |
| 60 | if (INDEX_INVALID == fei || |
| 61 | NULL == (fed = fib_entry_delegate_find(fib_entry_get(fei), |
| 62 | FIB_ENTRY_DELEGATE_TRACK))) |
| 63 | { |
| 64 | fed = fib_entry_track_delegate_add(fib_index, prefix); |
| 65 | } |
| 66 | |
| 67 | /* |
| 68 | * add this child to the entry's delegate |
| 69 | */ |
| 70 | *sibling = fib_node_child_add(FIB_NODE_TYPE_ENTRY_TRACK, |
| 71 | fib_entry_delegate_get_index(fed), |
| 72 | child_type, |
| 73 | child_index); |
| 74 | |
| 75 | return (fed->fd_entry_index); |
| 76 | } |
| 77 | |
| 78 | void |
| 79 | fib_entry_untrack (fib_node_index_t fei, |
| 80 | u32 sibling) |
| 81 | { |
| 82 | fib_entry_delegate_t *fed; |
| 83 | |
| 84 | fed = fib_entry_delegate_find(fib_entry_get(fei), |
| 85 | FIB_ENTRY_DELEGATE_TRACK); |
| 86 | |
| 87 | if (NULL != fed) |
| 88 | { |
| 89 | fib_node_child_remove(FIB_NODE_TYPE_ENTRY_TRACK, |
| 90 | fib_entry_delegate_get_index(fed), |
| 91 | sibling); |
| 92 | /* if this is the last child the delegate will be removed. */ |
| 93 | } |
| 94 | /* else untracked */ |
| 95 | } |
| 96 | |
| 97 | static fib_node_t * |
| 98 | fib_entry_track_get_node (fib_node_index_t index) |
| 99 | { |
| 100 | fib_entry_delegate_t *fed; |
| 101 | |
| 102 | fed = fib_entry_delegate_get(index); |
| 103 | return (&fed->fd_track.fedt_node); |
| 104 | } |
| 105 | |
| 106 | static fib_entry_delegate_t* |
| 107 | fib_entry_delegate_from_fib_node (fib_node_t *node) |
| 108 | { |
| 109 | ASSERT(FIB_NODE_TYPE_ENTRY_TRACK == node->fn_type); |
| 110 | return ((fib_entry_delegate_t *) (((char *) node) - |
| 111 | STRUCT_OFFSET_OF (fib_entry_delegate_t, |
| 112 | fd_track.fedt_node))); |
| 113 | } |
| 114 | |
| 115 | static void |
| 116 | fib_entry_track_last_lock_gone (fib_node_t *node) |
| 117 | { |
| 118 | fib_entry_delegate_t *fed; |
| 119 | fib_node_index_t fei; |
| 120 | u32 sibling; |
| 121 | |
| 122 | fed = fib_entry_delegate_from_fib_node(node); |
| 123 | fei = fed->fd_entry_index; |
| 124 | sibling = fed->fd_track.fedt_sibling; |
| 125 | |
| 126 | /* |
| 127 | * the tracker has no more children so it can be removed, |
| 128 | * and the FIB entry unsourced. |
| 129 | * remove the delegate first, then unlock the fib entry, |
| 130 | * since the delegate may be holding the last lock |
| 131 | */ |
| 132 | fib_entry_delegate_remove(fib_entry_get(fei), |
| 133 | FIB_ENTRY_DELEGATE_TRACK); |
| 134 | /* having removed the deletegate the fed object is now toast */ |
| 135 | fib_entry_child_remove(fei, sibling); |
| 136 | |
| 137 | fib_table_entry_delete_index(fei, FIB_SOURCE_RR); |
| 138 | } |
| 139 | |
| 140 | static fib_node_back_walk_rc_t |
| 141 | fib_entry_track_back_walk_notify (fib_node_t *node, |
| 142 | fib_node_back_walk_ctx_t *ctx) |
| 143 | { |
| 144 | fib_entry_delegate_t *fed; |
| 145 | |
| 146 | fed = fib_entry_delegate_from_fib_node(node); |
| 147 | |
| 148 | /* |
| 149 | * propagate the walk to the delgate's children |
| 150 | */ |
| 151 | |
| 152 | fib_walk_sync(FIB_NODE_TYPE_ENTRY_TRACK, |
| 153 | fib_entry_delegate_get_index(fed), |
| 154 | ctx); |
| 155 | |
| 156 | return (FIB_NODE_BACK_WALK_CONTINUE); |
| 157 | } |
| 158 | |
| 159 | static void |
| 160 | fib_entry_track_show_memory (void) |
| 161 | { |
| 162 | } |
| 163 | |
| 164 | /* |
| 165 | * The FIB entry tracker's graph node virtual function table |
| 166 | */ |
| 167 | static const fib_node_vft_t fib_entry_track_vft = { |
| 168 | .fnv_get = fib_entry_track_get_node, |
| 169 | .fnv_last_lock = fib_entry_track_last_lock_gone, |
| 170 | .fnv_back_walk = fib_entry_track_back_walk_notify, |
| 171 | .fnv_mem_show = fib_entry_track_show_memory, |
| 172 | }; |
| 173 | |
| 174 | void |
| 175 | fib_entry_track_module_init (void) |
| 176 | { |
| 177 | fib_node_register_type(FIB_NODE_TYPE_ENTRY_TRACK, &fib_entry_track_vft); |
| 178 | } |