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 union user_action_cookie;
  31 struct dpif_flow_stats;
  32 struct ofproto;
  33 struct ofproto_dpif;
  34 struct ofproto_packet_in;
  35 struct ofport_dpif;
  36 struct dpif_backer;
  37 struct OVS_LOCKABLE rule_dpif;
  38 struct OVS_LOCKABLE group_dpif;
  39
  40 enum rule_dpif_lookup_verdict {
  41     RULE_DPIF_LOOKUP_VERDICT_MATCH,         /* A match occurred. */
  42     RULE_DPIF_LOOKUP_VERDICT_CONTROLLER,    /* A miss occurred and the packet
  43                                              * should be passed to
  44                                              * the controller. */
  45     RULE_DPIF_LOOKUP_VERDICT_DROP,          /* A miss occurred and the packet
  46                                              * should be dropped. */
  47     RULE_DPIF_LOOKUP_VERDICT_DEFAULT,       /* A miss occurred and the packet
  48                                              * should handled by the default
  49                                              * miss behaviour.
  50                                              * For pre-OF1.3 it should be
  51                                              * forwarded to the controller.
  52                                              * For OF1.3+ it should be
  53                                              * dropped. */
  54 };
  55
  56 /* For lock annotation below only. */
  57 extern struct ovs_rwlock xlate_rwlock;
  58
  59 /* Ofproto-dpif -- DPIF based ofproto implementation.
  60  *
  61  * Ofproto-dpif provides an ofproto implementation for those platforms which
  62  * implement the netdev and dpif interface defined in netdev.h and dpif.h.  The
  63  * most important of which is the Linux Kernel Module (dpif-linux), but
  64  * alternatives are supported such as a userspace only implementation
  65  * (dpif-netdev), and a dummy implementation used for unit testing.
  66  *
  67  * Ofproto-dpif is divided into three major chunks.
  68  *
  69  * - ofproto-dpif.c
  70  *   The main ofproto-dpif module is responsible for implementing the
  71  *   provider interface, installing and removing datapath flows, maintaining
  72  *   packet statistics, running protocols (BFD, LACP, STP, etc), and
  73  *   configuring relevant submodules.
  74  *
  75  * - ofproto-dpif-upcall.c
  76  *   Ofproto-dpif-upcall is responsible for retrieving upcalls from the kernel,
  77  *   processing miss upcalls, and handing more complex ones up to the main
  78  *   ofproto-dpif module.  Miss upcall processing boils down to figuring out
  79  *   what each packet's actions are, executing them (i.e. asking the kernel to
  80  *   forward it), and handing it up to ofproto-dpif to decided whether or not
  81  *   to install a kernel flow.
  82  *
  83  * - ofproto-dpif-xlate.c
  84  *   Ofproto-dpif-xlate is responsible for translating translating OpenFlow
  85  *   actions into datapath actions. */
  86
  87 size_t ofproto_dpif_get_max_mpls_depth(const struct ofproto_dpif *);
  88 bool ofproto_dpif_get_enable_recirc(const struct ofproto_dpif *);
  89
  90 uint8_t rule_dpif_lookup(struct ofproto_dpif *, struct flow *,
  91                          struct flow_wildcards *, struct rule_dpif **rule,
  92                          bool take_ref);
  93
  94 enum rule_dpif_lookup_verdict rule_dpif_lookup_from_table(struct ofproto_dpif *,
  95                                                           const struct flow *,
  96                                                           struct flow_wildcards *,
  97                                                           bool force_controller_on_miss,
  98                                                           uint8_t *table_id,
  99                                                           struct rule_dpif **rule,
 100                                                           bool take_ref);
 101
 102 static inline void rule_dpif_ref(struct rule_dpif *);
 103 static inline void rule_dpif_unref(struct rule_dpif *);
 104
 105 void rule_dpif_credit_stats(struct rule_dpif *rule ,
 106                             const struct dpif_flow_stats *);
 107
 108 static inline bool rule_dpif_is_fail_open(const struct rule_dpif *);
 109 static inline bool rule_dpif_is_table_miss(const struct rule_dpif *);
 110 static inline bool rule_dpif_is_internal(const struct rule_dpif *);
 111
 112 uint8_t rule_dpif_get_table(const struct rule_dpif *);
 113
 114 bool table_is_internal(uint8_t table_id);
 115
 116 const struct rule_actions *rule_dpif_get_actions(const struct rule_dpif *);
 117
 118 ovs_be64 rule_dpif_get_flow_cookie(const struct rule_dpif *rule);
 119
 120 void rule_dpif_reduce_timeouts(struct rule_dpif *rule, uint16_t idle_timeout,
 121                                uint16_t hard_timeout);
 122
 123 void choose_miss_rule(enum ofputil_port_config,
 124                       struct rule_dpif *miss_rule,
 125                       struct rule_dpif *no_packet_in_rule,
 126                       struct rule_dpif **rule, bool take_ref);
 127
 128 bool group_dpif_lookup(struct ofproto_dpif *ofproto, uint32_t group_id,
 129                        struct group_dpif **group);
 130
 131 void group_dpif_release(struct group_dpif *group);
 132
 133 void group_dpif_get_buckets(const struct group_dpif *group,
 134                             const struct list **buckets);
 135 enum ofp11_group_type group_dpif_get_type(const struct group_dpif *group);
 136
 137 bool ofproto_has_vlan_splinters(const struct ofproto_dpif *);
 138 ofp_port_t vsp_realdev_to_vlandev(const struct ofproto_dpif *,
 139                                   ofp_port_t realdev_ofp_port,
 140                                   ovs_be16 vlan_tci);
 141 bool vsp_adjust_flow(const struct ofproto_dpif *, struct flow *);
 142
 143 int ofproto_dpif_execute_actions(struct ofproto_dpif *, const struct flow *,
 144                                  struct rule_dpif *, const struct ofpact *,
 145                                  size_t ofpacts_len, struct ofpbuf *)
 146     OVS_EXCLUDED(xlate_rwlock);
 147 void ofproto_dpif_send_packet_in(struct ofproto_dpif *,
 148                                  struct ofproto_packet_in *);
 149 bool ofproto_dpif_wants_packet_in_on_miss(struct ofproto_dpif *);
 150 int ofproto_dpif_send_packet(const struct ofport_dpif *, struct ofpbuf *);
 151 void ofproto_dpif_flow_mod(struct ofproto_dpif *, struct ofputil_flow_mod *);
 152 struct rule_dpif *ofproto_dpif_refresh_rule(struct rule_dpif *);
 153
 154 struct ofport_dpif *odp_port_to_ofport(const struct dpif_backer *, odp_port_t);
 155
 156 /*
 157  * Recirculation
 158  * =============
 159  *
 160  * Recirculation is a technique to allow a frame to re-enter the packet
 161  * processing path for one or multiple times to achieve more flexible packet
 162  * processing in the data path. MPLS handling and selecting bond slave port
 163  * of a bond ports.
 164  *
 165  * Data path and user space interface
 166  * -----------------------------------
 167  *
 168  * Two new fields, recirc_id and dp_hash, are added to the current flow data
 169  * structure. They are both of type uint32_t. In addition, a new action,
 170  * RECIRC, are added.
 171  *
 172  * The value recirc_id is used to distinguish a packet from multiple
 173  * iterations of recirculation. A packet initially received is considered of
 174  * having recirc_id of 0. Recirc_id is managed by the user space, opaque to
 175  * the data path.
 176  *
 177  * On the other hand, dp_hash can only be computed by the data path, opaque to
 178  * the user space. In fact, user space may not able to recompute the hash
 179  * value. The dp_hash value should be wildcarded when for a newly received
 180  * packet. RECIRC action specifies whether the hash is computed. If computed,
 181  * how many fields to be included in the hash computation. The computed hash
 182  * value is stored into the dp_hash field prior to recirculation.
 183  *
 184  * The RECIRC action computes and set the dp_hash field, set the recirc_id
 185  * field and then reprocess the packet as if it was received on the same input
 186  * port. RECIRC action works like a function call; actions listed behind the
 187  * RECIRC action will be executed after its execution.  RECIRC action can be
 188  * nested, data path implementation limits the number of recirculation executed
 189  * to prevent unreasonable nesting depth or infinite loop.
 190  *
 191  * Both flow fields and the RECIRC action are exposed as open flow fields via
 192  * Nicira extensions.
 193  *
 194  * Post recirculation flow
 195  * ------------------------
 196  *
 197  * At the open flow level, post recirculation rules are always hidden from the
 198  * controller.  They are installed in table 254 which is set up as a hidden
 199  * table during boot time. Those rules are managed by the local user space
 200  * program only.
 201  *
 202  * To speed up the classifier look up process, recirc_id is always reflected
 203  * into the metadata field, since recirc_id is required to be exactly matched.
 204  *
 205  * Classifier look up always starts with table 254. A post recirculation flow
 206  * lookup should find its hidden rule within this table. On the other hand, A
 207  * newly received packet should miss all post recirculation rules because its
 208  * recirc_id is zero, then hit a pre-installed lower priority rule to redirect
 209  * classifier to look up starting from table 0:
 210  *
 211  *       * , actions=resubmit(,0)
 212  *
 213  * Post recirculation data path flows are managed like other data path flows.
 214  * They are created on demand. Miss handling, stats collection and revalidation
 215  * work the same way as regular flows.
 216  */
 217
 218 uint32_t ofproto_dpif_alloc_recirc_id(struct ofproto_dpif *ofproto);
 219 void ofproto_dpif_free_recirc_id(struct ofproto_dpif *ofproto, uint32_t recirc_id);
 220 int ofproto_dpif_add_internal_flow(struct ofproto_dpif *,
 221                                    struct match *, int priority,
 222                                    const struct ofpbuf *ofpacts,
 223                                    struct rule **rulep);
 224 int ofproto_dpif_delete_internal_flow(struct ofproto_dpif *, struct match *,
 225                                       int priority);
 226
 227 /* Number of implemented OpenFlow tables. */
 228 enum { N_TABLES = 255 };
 229 enum { TBL_INTERNAL = N_TABLES - 1 };    /* Used for internal hidden rules. */
 230 BUILD_ASSERT_DECL(N_TABLES >= 2 && N_TABLES <= 255);
 231
 232 \f
 233 /* struct rule_dpif has struct rule as it's first member. */
 234 #define RULE_CAST(RULE) ((struct rule *)RULE)
 235
 236 static inline void rule_dpif_ref(struct rule_dpif *rule)
 237 {
 238     if (rule) {
 239         ofproto_rule_ref(RULE_CAST(rule));
 240     }
 241 }
 242
 243 static inline void rule_dpif_unref(struct rule_dpif *rule)
 244 {
 245     if (rule) {
 246         ofproto_rule_unref(RULE_CAST(rule));
 247     }
 248 }
 249
 250 static inline bool rule_dpif_is_fail_open(const struct rule_dpif *rule)
 251 {
 252     return is_fail_open_rule(RULE_CAST(rule));
 253 }
 254
 255 static inline bool rule_dpif_is_table_miss(const struct rule_dpif *rule)
 256 {
 257     return rule_is_table_miss(RULE_CAST(rule));
 258 }
 259
 260 /* Returns true if 'rule' is an internal rule, false otherwise. */
 261 static inline bool rule_dpif_is_internal(const struct rule_dpif *rule)
 262 {
 263     return RULE_CAST(rule)->table_id == TBL_INTERNAL;
 264 }
 265
 266 #undef RULE_CAST
 267
 268 #endif /* ofproto-dpif.h */