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 enum rule_dpif_lookup_verdict {
  44     RULE_DPIF_LOOKUP_VERDICT_MATCH,         /* A match occurred. */
  45     RULE_DPIF_LOOKUP_VERDICT_CONTROLLER,    /* A miss occurred and the packet
  46                                              * should be passed to
  47                                              * the controller. */
  48     RULE_DPIF_LOOKUP_VERDICT_DROP,          /* A miss occurred and the packet
  49                                              * should be dropped. */
  50     RULE_DPIF_LOOKUP_VERDICT_DEFAULT,       /* A miss occurred and the packet
  51                                              * should handled by the default
  52                                              * miss behaviour.
  53                                              * For pre-OF1.3 it should be
  54                                              * forwarded to the controller.
  55                                              * For OF1.3+ it should be
  56                                              * dropped. */
  57 };
  58
  59
  60 /* Ofproto-dpif -- DPIF based ofproto implementation.
  61  *
  62  * Ofproto-dpif provides an ofproto implementation for those platforms which
  63  * implement the netdev and dpif interface defined in netdev.h and dpif.h.  The
  64  * most important of which is the Linux Kernel Module (dpif-linux), but
  65  * alternatives are supported such as a userspace only implementation
  66  * (dpif-netdev), and a dummy implementation used for unit testing.
  67  *
  68  * Ofproto-dpif is divided into three major chunks.
  69  *
  70  * - ofproto-dpif.c
  71  *   The main ofproto-dpif module is responsible for implementing the
  72  *   provider interface, installing and removing datapath flows, maintaining
  73  *   packet statistics, running protocols (BFD, LACP, STP, etc), and
  74  *   configuring relevant submodules.
  75  *
  76  * - ofproto-dpif-upcall.c
  77  *   Ofproto-dpif-upcall is responsible for retrieving upcalls from the kernel,
  78  *   processing miss upcalls, and handing more complex ones up to the main
  79  *   ofproto-dpif module.  Miss upcall processing boils down to figuring out
  80  *   what each packet's actions are, executing them (i.e. asking the kernel to
  81  *   forward it), and handing it up to ofproto-dpif to decided whether or not
  82  *   to install a kernel flow.
  83  *
  84  * - ofproto-dpif-xlate.c
  85  *   Ofproto-dpif-xlate is responsible for translating OpenFlow actions into
  86  *   datapath actions. */
  87
  88 size_t ofproto_dpif_get_max_mpls_depth(const struct ofproto_dpif *);
  89 bool ofproto_dpif_get_enable_recirc(const struct ofproto_dpif *);
  90
  91 uint8_t rule_dpif_lookup(struct ofproto_dpif *, struct flow *,
  92                          struct flow_wildcards *, struct rule_dpif **rule,
  93                          bool take_ref, const struct dpif_flow_stats *);
  94
  95 enum rule_dpif_lookup_verdict rule_dpif_lookup_from_table(struct ofproto_dpif *,
  96                                                           const struct flow *,
  97                                                           struct flow_wildcards *,
  98                                                           bool force_controller_on_miss,
  99                                                           uint8_t *table_id,
 100                                                           struct rule_dpif **rule,
 101                                                           bool take_ref,
 102                                                           const struct dpif_flow_stats *);
 103
 104 static inline void rule_dpif_ref(struct rule_dpif *);
 105 static inline void rule_dpif_unref(struct rule_dpif *);
 106
 107 void rule_dpif_credit_stats(struct rule_dpif *rule ,
 108                             const struct dpif_flow_stats *);
 109
 110 static inline bool rule_dpif_is_fail_open(const struct rule_dpif *);
 111 static inline bool rule_dpif_is_table_miss(const struct rule_dpif *);
 112 static inline bool rule_dpif_is_internal(const struct rule_dpif *);
 113
 114 uint8_t rule_dpif_get_table(const struct rule_dpif *);
 115
 116 bool table_is_internal(uint8_t table_id);
 117
 118 const struct rule_actions *rule_dpif_get_actions(const struct rule_dpif *);
 119 uint32_t rule_dpif_get_recirc_id(struct rule_dpif *);
 120 void rule_set_recirc_id(struct rule *, uint32_t id);
 121
 122 ovs_be64 rule_dpif_get_flow_cookie(const struct rule_dpif *rule);
 123
 124 void rule_dpif_reduce_timeouts(struct rule_dpif *rule, uint16_t idle_timeout,
 125                                uint16_t hard_timeout);
 126
 127 void choose_miss_rule(enum ofputil_port_config,
 128                       struct rule_dpif *miss_rule,
 129                       struct rule_dpif *no_packet_in_rule,
 130                       struct rule_dpif **rule, bool take_ref);
 131
 132 void group_dpif_credit_stats(struct group_dpif *,
 133                              struct ofputil_bucket *,
 134                              const struct dpif_flow_stats *);
 135 bool group_dpif_lookup(struct ofproto_dpif *ofproto, uint32_t group_id,
 136                        struct group_dpif **group);
 137
 138 void group_dpif_get_buckets(const struct group_dpif *group,
 139                             const struct list **buckets);
 140 enum ofp11_group_type group_dpif_get_type(const struct group_dpif *group);
 141
 142 bool ofproto_has_vlan_splinters(const struct ofproto_dpif *);
 143 ofp_port_t vsp_realdev_to_vlandev(const struct ofproto_dpif *,
 144                                   ofp_port_t realdev_ofp_port,
 145                                   ovs_be16 vlan_tci);
 146 bool vsp_adjust_flow(const struct ofproto_dpif *, struct flow *,
 147                      struct ofpbuf *packet);
 148
 149 int ofproto_dpif_execute_actions(struct ofproto_dpif *, const struct flow *,
 150                                  struct rule_dpif *, const struct ofpact *,
 151                                  size_t ofpacts_len, struct ofpbuf *);
 152 void ofproto_dpif_send_packet_in(struct ofproto_dpif *,
 153                                  struct ofproto_packet_in *);
 154 bool ofproto_dpif_wants_packet_in_on_miss(struct ofproto_dpif *);
 155 int ofproto_dpif_send_packet(const struct ofport_dpif *, struct ofpbuf *);
 156 void ofproto_dpif_flow_mod(struct ofproto_dpif *, struct ofputil_flow_mod *);
 157 struct rule_dpif *ofproto_dpif_refresh_rule(struct rule_dpif *);
 158
 159 struct ofport_dpif *odp_port_to_ofport(const struct dpif_backer *, odp_port_t);
 160
 161 /*
 162  * Recirculation
 163  * =============
 164  *
 165  * Recirculation is a technique to allow a frame to re-enter the packet
 166  * processing path for one or multiple times to achieve more flexible packet
 167  * processing in the data path. MPLS handling and selecting bond slave port
 168  * of a bond ports.
 169  *
 170  * Data path and user space interface
 171  * -----------------------------------
 172  *
 173  * Two new fields, recirc_id and dp_hash, are added to the current flow data
 174  * structure. They are both of type uint32_t. In addition, a new action,
 175  * RECIRC, are added.
 176  *
 177  * The value recirc_id is used to distinguish a packet from multiple
 178  * iterations of recirculation. A packet initially received is considered of
 179  * having recirc_id of 0. Recirc_id is managed by the user space, opaque to
 180  * the data path.
 181  *
 182  * On the other hand, dp_hash can only be computed by the data path, opaque to
 183  * the user space. In fact, user space may not able to recompute the hash
 184  * value. The dp_hash value should be wildcarded when for a newly received
 185  * packet. RECIRC action specifies whether the hash is computed. If computed,
 186  * how many fields to be included in the hash computation. The computed hash
 187  * value is stored into the dp_hash field prior to recirculation.
 188  *
 189  * The RECIRC action computes and set the dp_hash field, set the recirc_id
 190  * field and then reprocess the packet as if it was received on the same input
 191  * port. RECIRC action works like a function call; actions listed behind the
 192  * RECIRC action will be executed after its execution.  RECIRC action can be
 193  * nested, data path implementation limits the number of recirculation executed
 194  * to prevent unreasonable nesting depth or infinite loop.
 195  *
 196  * Both flow fields and the RECIRC action are exposed as open flow fields via
 197  * Nicira extensions.
 198  *
 199  * Post recirculation flow
 200  * ------------------------
 201  *
 202  * At the open flow level, post recirculation rules are always hidden from the
 203  * controller.  They are installed in table 254 which is set up as a hidden
 204  * table during boot time. Those rules are managed by the local user space
 205  * program only.
 206  *
 207  * To speed up the classifier look up process, recirc_id is always reflected
 208  * into the metadata field, since recirc_id is required to be exactly matched.
 209  *
 210  * Classifier look up always starts with table 254. A post recirculation flow
 211  * lookup should find its hidden rule within this table. On the other hand, A
 212  * newly received packet should miss all post recirculation rules because its
 213  * recirc_id is zero, then hit a pre-installed lower priority rule to redirect
 214  * classifier to look up starting from table 0:
 215  *
 216  *       * , actions=resubmit(,0)
 217  *
 218  * Post recirculation data path flows are managed like other data path flows.
 219  * They are created on demand. Miss handling, stats collection and revalidation
 220  * work the same way as regular flows.
 221  */
 222
 223 uint32_t ofproto_dpif_alloc_recirc_id(struct ofproto_dpif *ofproto);
 224 void ofproto_dpif_free_recirc_id(struct ofproto_dpif *ofproto, uint32_t recirc_id);
 225 int ofproto_dpif_add_internal_flow(struct ofproto_dpif *,
 226                                    const struct match *, int priority,
 227                                    uint16_t idle_timeout,
 228                                    const struct ofpbuf *ofpacts,
 229                                    struct rule **rulep);
 230 int ofproto_dpif_delete_internal_flow(struct ofproto_dpif *, struct match *,
 231                                       int priority);
 232
 233 /* Number of implemented OpenFlow tables. */
 234 enum { N_TABLES = 255 };
 235 enum { TBL_INTERNAL = N_TABLES - 1 };    /* Used for internal hidden rules. */
 236 BUILD_ASSERT_DECL(N_TABLES >= 2 && N_TABLES <= 255);
 237
 238 \f
 239 /* struct rule_dpif has struct rule as it's first member. */
 240 #define RULE_CAST(RULE) ((struct rule *)RULE)
 241 #define GROUP_CAST(GROUP) ((struct ofgroup *)GROUP)
 242
 243 static inline struct group_dpif* group_dpif_ref(struct group_dpif *group)
 244 {
 245     if (group) {
 246         ofproto_group_ref(GROUP_CAST(group));
 247     }
 248     return group;
 249 }
 250
 251 static inline void group_dpif_unref(struct group_dpif *group)
 252 {
 253     if (group) {
 254         ofproto_group_unref(GROUP_CAST(group));
 255     }
 256 }
 257
 258 static inline void rule_dpif_ref(struct rule_dpif *rule)
 259 {
 260     if (rule) {
 261         ofproto_rule_ref(RULE_CAST(rule));
 262     }
 263 }
 264
 265 static inline bool rule_dpif_try_ref(struct rule_dpif *rule)
 266 {
 267     if (rule) {
 268         return ofproto_rule_try_ref(RULE_CAST(rule));
 269     }
 270     return false;
 271 }
 272
 273
 274 static inline void rule_dpif_unref(struct rule_dpif *rule)
 275 {
 276     if (rule) {
 277         ofproto_rule_unref(RULE_CAST(rule));
 278     }
 279 }
 280
 281 static inline bool rule_dpif_is_fail_open(const struct rule_dpif *rule)
 282 {
 283     return is_fail_open_rule(RULE_CAST(rule));
 284 }
 285
 286 static inline bool rule_dpif_is_table_miss(const struct rule_dpif *rule)
 287 {
 288     return rule_is_table_miss(RULE_CAST(rule));
 289 }
 290
 291 /* Returns true if 'rule' is an internal rule, false otherwise. */
 292 static inline bool rule_dpif_is_internal(const struct rule_dpif *rule)
 293 {
 294     return RULE_CAST(rule)->table_id == TBL_INTERNAL;
 295 }
 296
 297 #undef RULE_CAST
 298
 299 #endif /* ofproto-dpif.h */