ofproto/ofproto-dpif.h

   1 /* Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
   2  *
   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 #ifndef OFPROTO_DPIF_H
  16 #define OFPROTO_DPIF_H 1
  17
  18 #include <stdint.h>
  19
  20 #include "fail-open.h"
  21 #include "hmapx.h"
  22 #include "odp-util.h"
  23 #include "ofp-util.h"
  24 #include "ovs-thread.h"
  25 #include "ofproto-provider.h"
  26 #include "timer.h"
  27 #include "util.h"
  28 #include "ovs-thread.h"
  29
  30 /* Priority for internal rules created to handle recirculation */
  31 #define RECIRC_RULE_PRIORITY 20
  32
  33 union user_action_cookie;
  34 struct dpif_flow_stats;
  35 struct ofproto;
  36 struct ofproto_dpif;
  37 struct ofproto_packet_in;
  38 struct ofport_dpif;
  39 struct dpif_backer;
  40 struct OVS_LOCKABLE rule_dpif;
  41 struct OVS_LOCKABLE group_dpif;
  42
  43 /* Ofproto-dpif -- DPIF based ofproto implementation.
  44  *
  45  * Ofproto-dpif provides an ofproto implementation for those platforms which
  46  * implement the netdev and dpif interface defined in netdev.h and dpif.h.  The
  47  * most important of which is the Linux Kernel Module (dpif-linux), but
  48  * alternatives are supported such as a userspace only implementation
  49  * (dpif-netdev), and a dummy implementation used for unit testing.
  50  *
  51  * Ofproto-dpif is divided into three major chunks.
  52  *
  53  * - ofproto-dpif.c
  54  *   The main ofproto-dpif module is responsible for implementing the
  55  *   provider interface, installing and removing datapath flows, maintaining
  56  *   packet statistics, running protocols (BFD, LACP, STP, etc), and
  57  *   configuring relevant submodules.
  58  *
  59  * - ofproto-dpif-upcall.c
  60  *   Ofproto-dpif-upcall is responsible for retrieving upcalls from the kernel,
  61  *   processing miss upcalls, and handing more complex ones up to the main
  62  *   ofproto-dpif module.  Miss upcall processing boils down to figuring out
  63  *   what each packet's actions are, executing them (i.e. asking the kernel to
  64  *   forward it), and handing it up to ofproto-dpif to decided whether or not
  65  *   to install a kernel flow.
  66  *
  67  * - ofproto-dpif-xlate.c
  68  *   Ofproto-dpif-xlate is responsible for translating OpenFlow actions into
  69  *   datapath actions. */
  70
  71 size_t ofproto_dpif_get_max_mpls_depth(const struct ofproto_dpif *);
  72 bool ofproto_dpif_get_enable_recirc(const struct ofproto_dpif *);
  73
  74 struct rule_dpif *rule_dpif_lookup(struct ofproto_dpif *, struct flow *,
  75                                    struct flow_wildcards *, bool take_ref,
  76                                    const struct dpif_flow_stats *,
  77                                    uint8_t *table_id);
  78
  79 struct rule_dpif *rule_dpif_lookup_from_table(struct ofproto_dpif *,
  80                                               struct flow *,
  81                                               struct flow_wildcards *,
  82                                               bool take_ref,
  83                                               const struct dpif_flow_stats *,
  84                                               uint8_t *table_id,
  85                                               ofp_port_t in_port,
  86                                               bool may_packet_in,
  87                                               bool honor_table_miss);
  88
  89 static inline void rule_dpif_ref(struct rule_dpif *);
  90 static inline void rule_dpif_unref(struct rule_dpif *);
  91
  92 void rule_dpif_credit_stats(struct rule_dpif *rule ,
  93                             const struct dpif_flow_stats *);
  94
  95 static inline bool rule_dpif_is_fail_open(const struct rule_dpif *);
  96 static inline bool rule_dpif_is_table_miss(const struct rule_dpif *);
  97 static inline bool rule_dpif_is_internal(const struct rule_dpif *);
  98
  99 uint8_t rule_dpif_get_table(const struct rule_dpif *);
 100
 101 bool table_is_internal(uint8_t table_id);
 102
 103 const struct rule_actions *rule_dpif_get_actions(const struct rule_dpif *);
 104 uint32_t rule_dpif_get_recirc_id(struct rule_dpif *);
 105 void rule_set_recirc_id(struct rule *, uint32_t id);
 106
 107 ovs_be64 rule_dpif_get_flow_cookie(const struct rule_dpif *rule);
 108
 109 void rule_dpif_reduce_timeouts(struct rule_dpif *rule, uint16_t idle_timeout,
 110                                uint16_t hard_timeout);
 111
 112 void choose_miss_rule(enum ofputil_port_config,
 113                       struct rule_dpif *miss_rule,
 114                       struct rule_dpif *no_packet_in_rule,
 115                       struct rule_dpif **rule, bool take_ref);
 116
 117 void group_dpif_credit_stats(struct group_dpif *,
 118                              struct ofputil_bucket *,
 119                              const struct dpif_flow_stats *);
 120 bool group_dpif_lookup(struct ofproto_dpif *ofproto, uint32_t group_id,
 121                        struct group_dpif **group);
 122
 123 void group_dpif_get_buckets(const struct group_dpif *group,
 124                             const struct list **buckets);
 125 enum ofp11_group_type group_dpif_get_type(const struct group_dpif *group);
 126
 127 bool ofproto_has_vlan_splinters(const struct ofproto_dpif *);
 128 ofp_port_t vsp_realdev_to_vlandev(const struct ofproto_dpif *,
 129                                   ofp_port_t realdev_ofp_port,
 130                                   ovs_be16 vlan_tci);
 131 bool vsp_adjust_flow(const struct ofproto_dpif *, struct flow *,
 132                      struct ofpbuf *packet);
 133
 134 int ofproto_dpif_execute_actions(struct ofproto_dpif *, const struct flow *,
 135                                  struct rule_dpif *, const struct ofpact *,
 136                                  size_t ofpacts_len, struct ofpbuf *);
 137 void ofproto_dpif_send_packet_in(struct ofproto_dpif *,
 138                                  struct ofproto_packet_in *);
 139 bool ofproto_dpif_wants_packet_in_on_miss(struct ofproto_dpif *);
 140 int ofproto_dpif_send_packet(const struct ofport_dpif *, struct ofpbuf *);
 141 void ofproto_dpif_flow_mod(struct ofproto_dpif *, struct ofputil_flow_mod *);
 142 struct rule_dpif *ofproto_dpif_refresh_rule(struct rule_dpif *);
 143
 144 struct ofport_dpif *odp_port_to_ofport(const struct dpif_backer *, odp_port_t);
 145
 146 /*
 147  * Recirculation
 148  * =============
 149  *
 150  * Recirculation is a technique to allow a frame to re-enter the packet
 151  * processing path for one or multiple times to achieve more flexible packet
 152  * processing in the data path. MPLS handling and selecting bond slave port
 153  * of a bond ports.
 154  *
 155  * Data path and user space interface
 156  * -----------------------------------
 157  *
 158  * Two new fields, recirc_id and dp_hash, are added to the current flow data
 159  * structure. They are both of type uint32_t. In addition, a new action,
 160  * RECIRC, are added.
 161  *
 162  * The value recirc_id is used to distinguish a packet from multiple
 163  * iterations of recirculation. A packet initially received is considered of
 164  * having recirc_id of 0. Recirc_id is managed by the user space, opaque to
 165  * the data path.
 166  *
 167  * On the other hand, dp_hash can only be computed by the data path, opaque to
 168  * the user space. In fact, user space may not able to recompute the hash
 169  * value. The dp_hash value should be wildcarded when for a newly received
 170  * packet. RECIRC action specifies whether the hash is computed. If computed,
 171  * how many fields to be included in the hash computation. The computed hash
 172  * value is stored into the dp_hash field prior to recirculation.
 173  *
 174  * The RECIRC action computes and set the dp_hash field, set the recirc_id
 175  * field and then reprocess the packet as if it was received on the same input
 176  * port. RECIRC action works like a function call; actions listed behind the
 177  * RECIRC action will be executed after its execution.  RECIRC action can be
 178  * nested, data path implementation limits the number of recirculation executed
 179  * to prevent unreasonable nesting depth or infinite loop.
 180  *
 181  * Both flow fields and the RECIRC action are exposed as open flow fields via
 182  * Nicira extensions.
 183  *
 184  * Post recirculation flow
 185  * ------------------------
 186  *
 187  * At the open flow level, post recirculation rules are always hidden from the
 188  * controller.  They are installed in table 254 which is set up as a hidden
 189  * table during boot time. Those rules are managed by the local user space
 190  * program only.
 191  *
 192  * To speed up the classifier look up process, recirc_id is always reflected
 193  * into the metadata field, since recirc_id is required to be exactly matched.
 194  *
 195  * Classifier look up always starts with table 254. A post recirculation flow
 196  * lookup should find its hidden rule within this table. On the other hand, A
 197  * newly received packet should miss all post recirculation rules because its
 198  * recirc_id is zero, then hit a pre-installed lower priority rule to redirect
 199  * classifier to look up starting from table 0:
 200  *
 201  *       * , actions=resubmit(,0)
 202  *
 203  * Post recirculation data path flows are managed like other data path flows.
 204  * They are created on demand. Miss handling, stats collection and revalidation
 205  * work the same way as regular flows.
 206  */
 207
 208 uint32_t ofproto_dpif_alloc_recirc_id(struct ofproto_dpif *ofproto);
 209 void ofproto_dpif_free_recirc_id(struct ofproto_dpif *ofproto, uint32_t recirc_id);
 210 int ofproto_dpif_add_internal_flow(struct ofproto_dpif *,
 211                                    const struct match *, int priority,
 212                                    uint16_t idle_timeout,
 213                                    const struct ofpbuf *ofpacts,
 214                                    struct rule **rulep);
 215 int ofproto_dpif_delete_internal_flow(struct ofproto_dpif *, struct match *,
 216                                       int priority);
 217
 218 /* Number of implemented OpenFlow tables. */
 219 enum { N_TABLES = 255 };
 220 enum { TBL_INTERNAL = N_TABLES - 1 };    /* Used for internal hidden rules. */
 221 BUILD_ASSERT_DECL(N_TABLES >= 2 && N_TABLES <= 255);
 222
 223 \f
 224 /* struct rule_dpif has struct rule as it's first member. */
 225 #define RULE_CAST(RULE) ((struct rule *)RULE)
 226 #define GROUP_CAST(GROUP) ((struct ofgroup *)GROUP)
 227
 228 static inline struct group_dpif* group_dpif_ref(struct group_dpif *group)
 229 {
 230     if (group) {
 231         ofproto_group_ref(GROUP_CAST(group));
 232     }
 233     return group;
 234 }
 235
 236 static inline void group_dpif_unref(struct group_dpif *group)
 237 {
 238     if (group) {
 239         ofproto_group_unref(GROUP_CAST(group));
 240     }
 241 }
 242
 243 static inline void rule_dpif_ref(struct rule_dpif *rule)
 244 {
 245     if (rule) {
 246         ofproto_rule_ref(RULE_CAST(rule));
 247     }
 248 }
 249
 250 static inline bool rule_dpif_try_ref(struct rule_dpif *rule)
 251 {
 252     if (rule) {
 253         return ofproto_rule_try_ref(RULE_CAST(rule));
 254     }
 255     return false;
 256 }
 257
 258
 259 static inline void rule_dpif_unref(struct rule_dpif *rule)
 260 {
 261     if (rule) {
 262         ofproto_rule_unref(RULE_CAST(rule));
 263     }
 264 }
 265
 266 static inline bool rule_dpif_is_fail_open(const struct rule_dpif *rule)
 267 {
 268     return is_fail_open_rule(RULE_CAST(rule));
 269 }
 270
 271 static inline bool rule_dpif_is_table_miss(const struct rule_dpif *rule)
 272 {
 273     return rule_is_table_miss(RULE_CAST(rule));
 274 }
 275
 276 /* Returns true if 'rule' is an internal rule, false otherwise. */
 277 static inline bool rule_dpif_is_internal(const struct rule_dpif *rule)
 278 {
 279     return RULE_CAST(rule)->table_id == TBL_INTERNAL;
 280 }
 281
 282 #undef RULE_CAST
 283
 284 #endif /* ofproto-dpif.h */