datapath/flow.h

   1 /*
   2  * Copyright (c) 2007-2011 Nicira, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301, USA
  17  */
  18
  19 #ifndef FLOW_H
  20 #define FLOW_H 1
  21
  22 #include <linux/kernel.h>
  23 #include <linux/netlink.h>
  24 #include <linux/openvswitch.h>
  25 #include <linux/spinlock.h>
  26 #include <linux/types.h>
  27 #include <linux/rcupdate.h>
  28 #include <linux/if_ether.h>
  29 #include <linux/in6.h>
  30 #include <linux/jiffies.h>
  31 #include <linux/time.h>
  32 #include <linux/flex_array.h>
  33 #include <net/inet_ecn.h>
  34
  35 struct sk_buff;
  36
  37 struct sw_flow_actions {
  38         struct rcu_head rcu;
  39         u32 actions_len;
  40         struct nlattr actions[];
  41 };
  42
  43 struct sw_flow_key {
  44         struct {
  45                 __be64  tun_id;         /* Encapsulating tunnel ID. */
  46                 u32     priority;       /* Packet QoS priority. */
  47                 u16     in_port;        /* Input switch port (or DP_MAX_PORTS). */
  48         } phy;
  49         struct {
  50                 u8     src[ETH_ALEN];   /* Ethernet source address. */
  51                 u8     dst[ETH_ALEN];   /* Ethernet destination address. */
  52                 __be16 tci;             /* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
  53                 __be16 type;            /* Ethernet frame type. */
  54         } eth;
  55         struct {
  56                 u8     proto;           /* IP protocol or lower 8 bits of ARP opcode. */
  57                 u8     tos;             /* IP ToS. */
  58                 u8     ttl;             /* IP TTL/hop limit. */
  59                 u8     frag;            /* One of OVS_FRAG_TYPE_*. */
  60         } ip;
  61         union {
  62                 struct {
  63                         struct {
  64                                 __be32 src;     /* IP source address. */
  65                                 __be32 dst;     /* IP destination address. */
  66                         } addr;
  67                         union {
  68                                 struct {
  69                                         __be16 src;             /* TCP/UDP source port. */
  70                                         __be16 dst;             /* TCP/UDP destination port. */
  71                                 } tp;
  72                                 struct {
  73                                         u8 sha[ETH_ALEN];       /* ARP source hardware address. */
  74                                         u8 tha[ETH_ALEN];       /* ARP target hardware address. */
  75                                 } arp;
  76                         };
  77                 } ipv4;
  78                 struct {
  79                         struct {
  80                                 struct in6_addr src;    /* IPv6 source address. */
  81                                 struct in6_addr dst;    /* IPv6 destination address. */
  82                         } addr;
  83                         __be32 label;                   /* IPv6 flow label. */
  84                         struct {
  85                                 __be16 src;             /* TCP/UDP source port. */
  86                                 __be16 dst;             /* TCP/UDP destination port. */
  87                         } tp;
  88                         struct {
  89                                 struct in6_addr target; /* ND target address. */
  90                                 u8 sll[ETH_ALEN];       /* ND source link layer address. */
  91                                 u8 tll[ETH_ALEN];       /* ND target link layer address. */
  92                         } nd;
  93                 } ipv6;
  94         };
  95 };
  96
  97 struct sw_flow {
  98         struct rcu_head rcu;
  99         struct hlist_node hash_node[2];
 100         u32 hash;
 101
 102         struct sw_flow_key key;
 103         struct sw_flow_actions __rcu *sf_acts;
 104
 105         atomic_t refcnt;
 106         bool dead;
 107
 108         spinlock_t lock;        /* Lock for values below. */
 109         unsigned long used;     /* Last used time (in jiffies). */
 110         u64 packet_count;       /* Number of packets matched. */
 111         u64 byte_count;         /* Number of bytes matched. */
 112         u8 tcp_flags;           /* Union of seen TCP flags. */
 113 };
 114
 115 struct arp_eth_header {
 116         __be16      ar_hrd;     /* format of hardware address   */
 117         __be16      ar_pro;     /* format of protocol address   */
 118         unsigned char   ar_hln; /* length of hardware address   */
 119         unsigned char   ar_pln; /* length of protocol address   */
 120         __be16      ar_op;      /* ARP opcode (command)     */
 121
 122         /* Ethernet+IPv4 specific members. */
 123         unsigned char       ar_sha[ETH_ALEN];   /* sender hardware address  */
 124         unsigned char       ar_sip[4];          /* sender IP address        */
 125         unsigned char       ar_tha[ETH_ALEN];   /* target hardware address  */
 126         unsigned char       ar_tip[4];          /* target IP address        */
 127 } __packed;
 128
 129 int ovs_flow_init(void);
 130 void ovs_flow_exit(void);
 131
 132 struct sw_flow *ovs_flow_alloc(void);
 133 void ovs_flow_deferred_free(struct sw_flow *);
 134
 135 struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *);
 136 void ovs_flow_deferred_free_acts(struct sw_flow_actions *);
 137
 138 void ovs_flow_hold(struct sw_flow *);
 139 void ovs_flow_put(struct sw_flow *);
 140
 141 int ovs_flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *,
 142                      int *key_lenp);
 143 void ovs_flow_used(struct sw_flow *, struct sk_buff *);
 144 u64 ovs_flow_used_time(unsigned long flow_jiffies);
 145
 146 /* Upper bound on the length of a nlattr-formatted flow key.  The longest
 147  * nlattr-formatted flow key would be:
 148  *
 149  *                         struct  pad  nl hdr  total
 150  *                         ------  ---  ------  -----
 151  *  OVS_KEY_ATTR_PRIORITY      4    --     4      8
 152  *  OVS_KEY_ATTR_TUN_ID        8    --     4     12
 153  *  OVS_KEY_ATTR_IN_PORT       4    --     4      8
 154  *  OVS_KEY_ATTR_ETHERNET     12    --     4     16
 155  *  OVS_KEY_ATTR_8021Q         4    --     4      8
 156  *  OVS_KEY_ATTR_ETHERTYPE     2     2     4      8
 157  *  OVS_KEY_ATTR_IPV6         40    --     4     44
 158  *  OVS_KEY_ATTR_ICMPV6        2     2     4      8
 159  *  OVS_KEY_ATTR_ND           28    --     4     32
 160  *  -------------------------------------------------
 161  *  total                                       144
 162  */
 163 #define FLOW_BUFSIZE 144
 164
 165 int ovs_flow_to_nlattrs(const struct sw_flow_key *, struct sk_buff *);
 166 int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
 167                       const struct nlattr *);
 168 int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port, __be64 *tun_id,
 169                                    const struct nlattr *);
 170
 171 #define MAX_ACTIONS_BUFSIZE     (16 * 1024)
 172 #define TBL_MIN_BUCKETS         1024
 173
 174 struct flow_table {
 175         struct flex_array *buckets;
 176         unsigned int count, n_buckets;
 177         struct rcu_head rcu;
 178         int node_ver;
 179         u32 hash_seed;
 180         bool keep_flows;
 181 };
 182
 183 static inline int ovs_flow_tbl_count(struct flow_table *table)
 184 {
 185         return table->count;
 186 }
 187
 188 static inline int ovs_flow_tbl_need_to_expand(struct flow_table *table)
 189 {
 190         return (table->count > table->n_buckets);
 191 }
 192
 193 struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
 194                                     struct sw_flow_key *key, int len);
 195 void ovs_flow_tbl_destroy(struct flow_table *table);
 196 void ovs_flow_tbl_deferred_destroy(struct flow_table *table);
 197 struct flow_table *ovs_flow_tbl_alloc(int new_size);
 198 struct flow_table *ovs_flow_tbl_expand(struct flow_table *table);
 199 struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table);
 200 void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow);
 201 void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow);
 202 u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len);
 203
 204 struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *idx);
 205 extern const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1];
 206
 207 #endif /* flow.h */