datapath/flow.h

   1 /*
   2  * Copyright (c) 2009, 2010, 2011 Nicira Networks.
   3  * Distributed under the terms of the GNU GPL version 2.
   4  *
   5  * Significant portions of this file may be copied from parts of the Linux
   6  * kernel, by Linus Torvalds and others.
   7  */
   8
   9 #ifndef FLOW_H
  10 #define FLOW_H 1
  11
  12 #include <linux/kernel.h>
  13 #include <linux/netlink.h>
  14 #include <linux/spinlock.h>
  15 #include <linux/types.h>
  16 #include <linux/rcupdate.h>
  17 #include <linux/if_ether.h>
  18 #include <linux/in6.h>
  19 #include <linux/jiffies.h>
  20 #include <linux/time.h>
  21 #include <linux/flex_array.h>
  22 #include "openvswitch/datapath-protocol.h"
  23
  24 struct sk_buff;
  25
  26 struct sw_flow_actions {
  27         struct rcu_head rcu;
  28         u32 actions_len;
  29         struct nlattr actions[];
  30 };
  31
  32 struct sw_flow_key {
  33         struct {
  34                 __be64 tun_id;          /* Encapsulating tunnel ID. */
  35                 u16    in_port;         /* Input switch port (or USHRT_MAX). */
  36                 u8     src[ETH_ALEN];   /* Ethernet source address. */
  37                 u8     dst[ETH_ALEN];   /* Ethernet destination address. */
  38                 __be16 tci;             /* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
  39                 __be16 type;            /* Ethernet frame type. */
  40         } eth;
  41         struct {
  42                 u8     proto;           /* IP protocol or lower 8 bits of ARP opcode. */
  43                 u8     tos;             /* IP ToS (DSCP field, 6 bits). */
  44         } ip;
  45         union {
  46                 struct {
  47                         struct {
  48                                 __be32 src;     /* IP source address. */
  49                                 __be32 dst;     /* IP destination address. */
  50                         } addr;
  51                         union {
  52                                 struct {
  53                                         __be16 src;             /* TCP/UDP source port. */
  54                                         __be16 dst;             /* TCP/UDP destination port. */
  55                                 } tp;
  56                                 struct {
  57                                         u8 sha[ETH_ALEN];       /* ARP source hardware address. */
  58                                         u8 tha[ETH_ALEN];       /* ARP target hardware address. */
  59                                 } arp;
  60                         };
  61                 } ipv4;
  62                 struct {
  63                         struct {
  64                                 struct in6_addr src;    /* IPv6 source address. */
  65                                 struct in6_addr dst;    /* IPv6 destination address. */
  66                         } addr;
  67                         struct {
  68                                 __be16 src;             /* TCP/UDP source port. */
  69                                 __be16 dst;             /* TCP/UDP destination port. */
  70                         } tp;
  71                         struct {
  72                                 struct in6_addr target; /* ND target address. */
  73                                 u8 sll[ETH_ALEN];       /* ND source link layer address. */
  74                                 u8 tll[ETH_ALEN];       /* ND target link layer address. */
  75                         } nd;
  76                 } ipv6;
  77         };
  78 };
  79
  80 struct sw_flow {
  81         struct rcu_head rcu;
  82         struct hlist_node  hash_node;
  83         u32 hash;
  84
  85         struct sw_flow_key key;
  86         struct sw_flow_actions __rcu *sf_acts;
  87
  88         atomic_t refcnt;
  89         bool dead;
  90
  91         spinlock_t lock;        /* Lock for values below. */
  92         unsigned long used;     /* Last used time (in jiffies). */
  93         u64 packet_count;       /* Number of packets matched. */
  94         u64 byte_count;         /* Number of bytes matched. */
  95         u8 tcp_flags;           /* Union of seen TCP flags. */
  96 };
  97
  98 struct arp_eth_header
  99 {
 100         __be16      ar_hrd;     /* format of hardware address   */
 101         __be16      ar_pro;     /* format of protocol address   */
 102         unsigned char   ar_hln; /* length of hardware address   */
 103         unsigned char   ar_pln; /* length of protocol address   */
 104         __be16      ar_op;      /* ARP opcode (command)     */
 105
 106         /* Ethernet+IPv4 specific members. */
 107         unsigned char       ar_sha[ETH_ALEN];   /* sender hardware address  */
 108         unsigned char       ar_sip[4];          /* sender IP address        */
 109         unsigned char       ar_tha[ETH_ALEN];   /* target hardware address  */
 110         unsigned char       ar_tip[4];          /* target IP address        */
 111 } __packed;
 112
 113 int flow_init(void);
 114 void flow_exit(void);
 115
 116 struct sw_flow *flow_alloc(void);
 117 void flow_deferred_free(struct sw_flow *);
 118
 119 struct sw_flow_actions *flow_actions_alloc(const struct nlattr *);
 120 void flow_deferred_free_acts(struct sw_flow_actions *);
 121
 122 void flow_hold(struct sw_flow *);
 123 void flow_put(struct sw_flow *);
 124
 125 int flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *,
 126                  int *key_lenp, bool *is_frag);
 127 void flow_used(struct sw_flow *, struct sk_buff *);
 128 u64 flow_used_time(unsigned long flow_jiffies);
 129
 130 /* Upper bound on the length of a nlattr-formatted flow key.  The longest
 131  * nlattr-formatted flow key would be:
 132  *
 133  *                         struct  pad  nl hdr  total
 134  *                         ------  ---  ------  -----
 135  *  OVS_KEY_ATTR_TUN_ID        8    --     4     12
 136  *  OVS_KEY_ATTR_IN_PORT       4    --     4      8
 137  *  OVS_KEY_ATTR_ETHERNET     12    --     4     16
 138  *  OVS_KEY_ATTR_8021Q         4    --     4      8
 139  *  OVS_KEY_ATTR_ETHERTYPE     2     2     4      8
 140  *  OVS_KEY_ATTR_IPV6         34     2     4     40
 141  *  OVS_KEY_ATTR_ICMPV6        2     2     4      8
 142  *  OVS_KEY_ATTR_ND           28    --     4     32
 143  *  -------------------------------------------------
 144  *  total                                       132
 145  */
 146 #define FLOW_BUFSIZE 132
 147
 148 int flow_to_nlattrs(const struct sw_flow_key *, struct sk_buff *);
 149 int flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
 150                       const struct nlattr *);
 151 int flow_metadata_from_nlattrs(u16 *in_port, __be64 *tun_id,
 152                                const struct nlattr *);
 153
 154 #define TBL_MIN_BUCKETS         1024
 155
 156 struct flow_table {
 157         struct flex_array *buckets;
 158         unsigned int count, n_buckets;
 159         struct rcu_head rcu;
 160 };
 161
 162 static inline int flow_tbl_count(struct flow_table *table)
 163 {
 164         return table->count;
 165 }
 166
 167 static inline int flow_tbl_need_to_expand(struct flow_table *table)
 168 {
 169         return (table->count > table->n_buckets);
 170 }
 171
 172 struct sw_flow *flow_tbl_lookup(struct flow_table *table,
 173                                 struct sw_flow_key *key,    int len);
 174 void flow_tbl_destroy(struct flow_table *table);
 175 void flow_tbl_deferred_destroy(struct flow_table *table);
 176 struct flow_table *flow_tbl_alloc(int new_size);
 177 struct flow_table *flow_tbl_expand(struct flow_table *table);
 178 void flow_tbl_insert(struct flow_table *table, struct sw_flow *flow);
 179 void flow_tbl_remove(struct flow_table *table, struct sw_flow *flow);
 180 u32 flow_hash(const struct sw_flow_key *key, int key_len);
 181
 182 struct sw_flow *flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *idx);
 183
 184 #endif /* flow.h */