lib/odp-util.h

   1 /*
   2  * Copyright (c) 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef ODP_UTIL_H
  18 #define ODP_UTIL_H 1
  19
  20 #include <stdbool.h>
  21 #include <stddef.h>
  22 #include <stdint.h>
  23 #include <string.h>
  24 #include <linux/openvswitch.h>
  25 #include "hash.h"
  26 #include "openflow/openflow.h"
  27 #include "util.h"
  28
  29 struct ds;
  30 struct flow;
  31 struct flow_tnl;
  32 struct nlattr;
  33 struct ofpbuf;
  34 struct simap;
  35
  36 #define OVSP_NONE UINT32_MAX
  37
  38 void format_odp_actions(struct ds *, const struct nlattr *odp_actions,
  39                         size_t actions_len);
  40 int odp_actions_from_string(const char *, const struct simap *port_names,
  41                             struct ofpbuf *odp_actions);
  42
  43 /* The maximum number of bytes that odp_flow_key_from_flow() appends to a
  44  * buffer.  This is the upper bound on the length of a nlattr-formatted flow
  45  * key that ovs-vswitchd fully understands.
  46  *
  47  * OVS doesn't insist that ovs-vswitchd and the datapath have exactly the same
  48  * idea of a flow, so therefore this value isn't necessarily an upper bound on
  49  * the length of a flow key that the datapath can pass to ovs-vswitchd.
  50  *
  51  * The longest nlattr-formatted flow key appended by odp_flow_key_from_flow()
  52  * would be:
  53  *
  54  *                                     struct  pad  nl hdr  total
  55  *                                     ------  ---  ------  -----
  56  *  OVS_KEY_ATTR_PRIORITY                4    --     4      8
  57  *  OVS_KEY_ATTR_TUNNEL                  0    --     4      4
  58  *  - OVS_TUNNEL_KEY_ATTR_ID             8    --     4     12
  59  *  - OVS_TUNNEL_KEY_ATTR_IPV4_SRC       4    --     4      8
  60  *  - OVS_TUNNEL_KEY_ATTR_IPV4_DST       4    --     4      8
  61  *  - OVS_TUNNEL_KEY_ATTR_TOS            1    3      4      8
  62  *  - OVS_TUNNEL_KEY_ATTR_TTL            1    3      4      8
  63  *  - OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT  0    --     4      4
  64  *  - OVS_TUNNEL_KEY_ATTR_CSUM           0    --     4      4
  65  *  OVS_KEY_ATTR_IN_PORT                 4    --     4      8
  66  *  OVS_KEY_ATTR_SKB_MARK                4    --     4      8
  67  *  OVS_KEY_ATTR_ETHERNET               12    --     4     16
  68  *  OVS_KEY_ATTR_ETHERTYPE               2     2     4      8  (outer VLAN ethertype)
  69  *  OVS_KEY_ATTR_8021Q                   4    --     4      8
  70  *  OVS_KEY_ATTR_ENCAP                   0    --     4      4  (VLAN encapsulation)
  71  *  OVS_KEY_ATTR_ETHERTYPE               2     2     4      8  (inner VLAN ethertype)
  72  *  OVS_KEY_ATTR_IPV6                   40    --     4     44
  73  *  OVS_KEY_ATTR_ICMPV6                  2     2     4      8
  74  *  OVS_KEY_ATTR_ND                     28    --     4     32
  75  *  ----------------------------------------------------------
  76  *  total                                                 208
  77  *
  78  * We include some slack space in case the calculation isn't quite right or we
  79  * add another field and forget to adjust this value.
  80  */
  81 #define ODPUTIL_FLOW_KEY_BYTES 256
  82
  83 /* A buffer with sufficient size and alignment to hold an nlattr-formatted flow
  84  * key.  An array of "struct nlattr" might not, in theory, be sufficiently
  85  * aligned because it only contains 16-bit types. */
  86 struct odputil_keybuf {
  87     uint32_t keybuf[DIV_ROUND_UP(ODPUTIL_FLOW_KEY_BYTES, 4)];
  88 };
  89
  90 void odp_flow_key_format(const struct nlattr *, size_t, struct ds *);
  91 int odp_flow_key_from_string(const char *s, const struct simap *port_names,
  92                              struct ofpbuf *);
  93
  94 void odp_flow_key_from_flow(struct ofpbuf *, const struct flow *,
  95                             uint32_t odp_in_port);
  96
  97 uint32_t odp_flow_key_hash(const struct nlattr *, size_t);
  98
  99 /* How well a kernel-provided flow key (a sequence of OVS_KEY_ATTR_*
 100  * attributes) matches OVS userspace expectations.
 101  *
 102  * These values are arranged so that greater values are "more important" than
 103  * lesser ones.  In particular, a single flow key can fit the descriptions for
 104  * both ODP_FIT_TOO_LITTLE and ODP_FIT_TOO_MUCH.  Such a key is treated as
 105  * ODP_FIT_TOO_LITTLE. */
 106 enum odp_key_fitness {
 107     ODP_FIT_PERFECT,            /* The key had exactly the fields we expect. */
 108     ODP_FIT_TOO_MUCH,           /* The key had fields we don't understand. */
 109     ODP_FIT_TOO_LITTLE,         /* The key lacked fields we expected to see. */
 110     ODP_FIT_ERROR,              /* The key was invalid. */
 111 };
 112 enum odp_key_fitness odp_flow_key_to_flow(const struct nlattr *, size_t,
 113                                           struct flow *);
 114 const char *odp_key_fitness_to_string(enum odp_key_fitness);
 115
 116 void commit_odp_tunnel_action(const struct flow *, struct flow *base,
 117                               struct ofpbuf *odp_actions);
 118 void commit_odp_actions(const struct flow *, struct flow *base,
 119                         struct ofpbuf *odp_actions);
 120 \f
 121 /* ofproto-dpif interface.
 122  *
 123  * The following types and functions are logically part of ofproto-dpif.
 124  * ofproto-dpif puts values of these types into the flows that it installs in
 125  * the kernel datapath, though, so ovs-dpctl needs to interpret them so that
 126  * it can print flows in a more human-readable manner. */
 127
 128 enum user_action_cookie_type {
 129     USER_ACTION_COOKIE_UNSPEC,
 130     USER_ACTION_COOKIE_SFLOW,        /* Packet for per-bridge sFlow sampling. */
 131     USER_ACTION_COOKIE_SLOW_PATH,    /* Userspace must process this flow. */
 132     USER_ACTION_COOKIE_FLOW_SAMPLE,  /* Packet for per-flow sampling. */
 133     USER_ACTION_COOKIE_IPFIX,        /* Packet for per-bridge IPFIX sampling. */
 134 };
 135
 136 /* user_action_cookie is passed as argument to OVS_ACTION_ATTR_USERSPACE.
 137  * Since it is passed to kernel as u64, its size has to be 8 bytes. */
 138 union user_action_cookie {
 139     uint16_t type;              /* enum user_action_cookie_type. */
 140
 141     struct {
 142         uint16_t type;          /* USER_ACTION_COOKIE_SFLOW. */
 143         ovs_be16 vlan_tci;      /* Destination VLAN TCI. */
 144         uint32_t output;        /* SFL_FLOW_SAMPLE_TYPE 'output' value. */
 145     } sflow;
 146
 147     struct {
 148         uint16_t type;          /* USER_ACTION_COOKIE_SLOW_PATH. */
 149         uint16_t unused;
 150         uint32_t reason;        /* enum slow_path_reason. */
 151     } slow_path;
 152
 153     struct {
 154         uint16_t type;          /* USER_ACTION_COOKIE_FLOW_SAMPLE. */
 155         uint16_t probability;   /* Sampling probability. */
 156         uint32_t collector_set_id; /* ID of IPFIX collector set. */
 157         uint32_t obs_domain_id; /* Observation Domain ID. */
 158         uint32_t obs_point_id;  /* Observation Point ID. */
 159     } flow_sample;
 160
 161     struct {
 162         uint16_t type;          /* USER_ACTION_COOKIE_IPFIX. */
 163     } ipfix;
 164 };
 165 BUILD_ASSERT_DECL(sizeof(union user_action_cookie) == 16);
 166
 167 size_t odp_put_userspace_action(uint32_t pid,
 168                                 const void *userdata, size_t userdata_size,
 169                                 struct ofpbuf *odp_actions);
 170 void odp_put_tunnel_action(const struct flow_tnl *tunnel,
 171                            struct ofpbuf *odp_actions);
 172 void odp_put_skb_mark_action(const uint32_t skb_mark,
 173                              struct ofpbuf *odp_actions);
 174
 175 /* Reasons why a subfacet might not be fast-pathable. */
 176 enum slow_path_reason {
 177     /* These reasons are mutually exclusive. */
 178     SLOW_CFM = 1 << 0,          /* CFM packets need per-packet processing. */
 179     SLOW_LACP = 1 << 1,         /* LACP packets need per-packet processing. */
 180     SLOW_STP = 1 << 2,          /* STP packets need per-packet processing. */
 181     SLOW_IN_BAND = 1 << 3,      /* In-band control needs every packet. */
 182
 183     /* Mutually exclusive with SLOW_CFM, SLOW_LACP, SLOW_STP.
 184      * Could possibly appear with SLOW_IN_BAND. */
 185     SLOW_CONTROLLER = 1 << 4,   /* Packets must go to OpenFlow controller. */
 186
 187     /* This can appear on its own, or, theoretically at least, along with any
 188      * other combination of reasons. */
 189     SLOW_MATCH = 1 << 5,        /* Datapath can't match specifically enough. */
 190 };
 191
 192 #endif /* odp-util.h */