ovs-rcu: Comment fixes.

[ovs.git] / lib / flow.h

/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Nicira, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
#ifndef FLOW_H
#define FLOW_H 1

#include <sys/types.h>
#include <netinet/in.h>
#include <stdbool.h>
#include <stdint.h>
#include <string.h>
#include "byte-order.h"
#include "openflow/nicira-ext.h"
#include "openflow/openflow.h"
#include "packets.h"
#include "hash.h"
#include "util.h"

struct dpif_flow_stats;
struct ds;
struct flow_wildcards;
struct minimask;
struct dp_packet;
struct pkt_metadata;
struct match;

/* This sequence number should be incremented whenever anything involving flows
 * or the wildcarding of flows changes.  This will cause build assertion
 * failures in places which likely need to be updated. */
#define FLOW_WC_SEQ 31

/* Number of Open vSwitch extension 32-bit registers. */
#define FLOW_N_REGS 8
BUILD_ASSERT_DECL(FLOW_N_REGS <= NXM_NX_MAX_REGS);
BUILD_ASSERT_DECL(FLOW_N_REGS % 2 == 0); /* Even. */

/* Number of OpenFlow 1.5+ 64-bit registers.
 *
 * Each of these overlays a pair of Open vSwitch 32-bit registers, so there
 * are half as many of them.*/
#define FLOW_N_XREGS (FLOW_N_REGS / 2)

/* Used for struct flow's dl_type member for frames that have no Ethernet
 * type, that is, pure 802.2 frames. */
#define FLOW_DL_TYPE_NONE 0x5ff

/* Fragment bits, used for IPv4 and IPv6, always zero for non-IP flows. */
#define FLOW_NW_FRAG_ANY   (1 << 0) /* Set for any IP frag. */
#define FLOW_NW_FRAG_LATER (1 << 1) /* Set for IP frag with nonzero offset. */
#define FLOW_NW_FRAG_MASK  (FLOW_NW_FRAG_ANY | FLOW_NW_FRAG_LATER)

BUILD_ASSERT_DECL(FLOW_NW_FRAG_ANY == NX_IP_FRAG_ANY);
BUILD_ASSERT_DECL(FLOW_NW_FRAG_LATER == NX_IP_FRAG_LATER);

#define FLOW_TNL_F_DONT_FRAGMENT (1 << 0)
#define FLOW_TNL_F_CSUM (1 << 1)
#define FLOW_TNL_F_KEY (1 << 2)
#define FLOW_TNL_F_OAM (1 << 3)

#define FLOW_TNL_F_MASK ((1 << 4) - 1)

const char *flow_tun_flag_to_string(uint32_t flags);

/* Maximum number of supported MPLS labels. */
#define FLOW_MAX_MPLS_LABELS 3

/*
 * A flow in the network.
 *
 * Must be initialized to all zeros to make any compiler-induced padding
 * zeroed.  Helps also in keeping unused fields (such as mutually exclusive
 * IPv4 and IPv6 addresses) zeroed out.
 *
 * The meaning of 'in_port' is context-dependent.  In most cases, it is a
 * 16-bit OpenFlow 1.0 port number.  In the software datapath interface (dpif)
 * layer and its implementations (e.g. dpif-netlink, dpif-netdev), it is
 * instead a 32-bit datapath port number.
 *
 * The fields are organized in four segments to facilitate staged lookup, where
 * lower layer fields are first used to determine if the later fields need to
 * be looked at.  This enables better wildcarding for datapath flows.
 *
 * NOTE: Order of the fields is significant, any change in the order must be
 * reflected in miniflow_extract()!
 */
struct flow {
    /* Metadata */
    struct flow_tnl tunnel;     /* Encapsulating tunnel parameters. */
    ovs_be64 metadata;          /* OpenFlow Metadata. */
    uint32_t regs[FLOW_N_REGS]; /* Registers. */
    uint32_t skb_priority;      /* Packet priority for QoS. */
    uint32_t pkt_mark;          /* Packet mark. */
    uint32_t dp_hash;           /* Datapath computed hash value. The exact
                                 * computation is opaque to the user space. */
    union flow_in_port in_port; /* Input port.*/
    uint32_t recirc_id;         /* Must be exact match. */
    uint32_t conj_id;           /* Conjunction ID. */
    ofp_port_t actset_output;   /* Output port in action set. */
    uint8_t pad1[6];            /* Pad to 64 bits. */

    /* L2, Order the same as in the Ethernet header! (64-bit aligned) */
    uint8_t dl_dst[ETH_ADDR_LEN]; /* Ethernet destination address. */
    uint8_t dl_src[ETH_ADDR_LEN]; /* Ethernet source address. */
    ovs_be16 dl_type;           /* Ethernet frame type. */
    ovs_be16 vlan_tci;          /* If 802.1Q, TCI | VLAN_CFI; otherwise 0. */
    ovs_be32 mpls_lse[ROUND_UP(FLOW_MAX_MPLS_LABELS, 2)]; /* MPLS label stack
                                                             (with padding). */
    /* L3 (64-bit aligned) */
    ovs_be32 nw_src;            /* IPv4 source address. */
    ovs_be32 nw_dst;            /* IPv4 destination address. */
    struct in6_addr ipv6_src;   /* IPv6 source address. */
    struct in6_addr ipv6_dst;   /* IPv6 destination address. */
    ovs_be32 ipv6_label;        /* IPv6 flow label. */
    uint8_t nw_frag;            /* FLOW_FRAG_* flags. */
    uint8_t nw_tos;             /* IP ToS (including DSCP and ECN). */
    uint8_t nw_ttl;             /* IP TTL/Hop Limit. */
    uint8_t nw_proto;           /* IP protocol or low 8 bits of ARP opcode. */
    struct in6_addr nd_target;  /* IPv6 neighbor discovery (ND) target. */
    uint8_t arp_sha[ETH_ADDR_LEN]; /* ARP/ND source hardware address. */
    uint8_t arp_tha[ETH_ADDR_LEN]; /* ARP/ND target hardware address. */
    ovs_be16 tcp_flags;         /* TCP flags. With L3 to avoid matching L4. */
    ovs_be16 pad2;              /* Pad to 64 bits. */

    /* L4 (64-bit aligned) */
    ovs_be16 tp_src;            /* TCP/UDP/SCTP source port. */
    ovs_be16 tp_dst;            /* TCP/UDP/SCTP destination port. */
    ovs_be32 igmp_group_ip4;    /* IGMP group IPv4 address.
                                 * Keep last for BUILD_ASSERT_DECL below. */
};
BUILD_ASSERT_DECL(sizeof(struct flow) % sizeof(uint64_t) == 0);

#define FLOW_U64S (sizeof(struct flow) / sizeof(uint64_t))

/* Some flow fields are mutually exclusive or only appear within the flow
 * pipeline.  IPv6 headers are bigger than IPv4 and MPLS, and IPv6 ND packets
 * are bigger than TCP,UDP and IGMP packets. */
#define FLOW_MAX_PACKET_U64S (FLOW_U64S                                   \
    /* Unused in datapath */  - FLOW_U64_SIZE(regs)                       \
                              - FLOW_U64_SIZE(metadata)                   \
    /* L2.5/3 */              - FLOW_U64_SIZE(nw_src)  /* incl. nw_dst */ \
                              - FLOW_U64_SIZE(mpls_lse)                   \
    /* L4 */                  - FLOW_U64_SIZE(tp_src)                     \
                             )

/* Remember to update FLOW_WC_SEQ when changing 'struct flow'. */
BUILD_ASSERT_DECL(offsetof(struct flow, igmp_group_ip4) + sizeof(uint32_t)
                  == sizeof(struct flow_tnl) + 192
                  && FLOW_WC_SEQ == 31);

/* Incremental points at which flow classification may be performed in
 * segments.
 * This is located here since this is dependent on the structure of the
 * struct flow defined above:
 * Each offset must be on a distinct, successive U64 boundary strictly
 * within the struct flow. */
enum {
    FLOW_SEGMENT_1_ENDS_AT = offsetof(struct flow, dl_dst),
    FLOW_SEGMENT_2_ENDS_AT = offsetof(struct flow, nw_src),
    FLOW_SEGMENT_3_ENDS_AT = offsetof(struct flow, tp_src),
};
BUILD_ASSERT_DECL(FLOW_SEGMENT_1_ENDS_AT % sizeof(uint64_t) == 0);
BUILD_ASSERT_DECL(FLOW_SEGMENT_2_ENDS_AT % sizeof(uint64_t) == 0);
BUILD_ASSERT_DECL(FLOW_SEGMENT_3_ENDS_AT % sizeof(uint64_t) == 0);
BUILD_ASSERT_DECL(                     0 < FLOW_SEGMENT_1_ENDS_AT);
BUILD_ASSERT_DECL(FLOW_SEGMENT_1_ENDS_AT < FLOW_SEGMENT_2_ENDS_AT);
BUILD_ASSERT_DECL(FLOW_SEGMENT_2_ENDS_AT < FLOW_SEGMENT_3_ENDS_AT);
BUILD_ASSERT_DECL(FLOW_SEGMENT_3_ENDS_AT < sizeof(struct flow));

extern const uint8_t flow_segment_u64s[];

void flow_extract(struct dp_packet *, struct flow *);

void flow_zero_wildcards(struct flow *, const struct flow_wildcards *);
void flow_unwildcard_tp_ports(const struct flow *, struct flow_wildcards *);
void flow_get_metadata(const struct flow *, struct match *flow_metadata);

char *flow_to_string(const struct flow *);
void format_flags(struct ds *ds, const char *(*bit_to_string)(uint32_t),
                  uint32_t flags, char del);
void format_flags_masked(struct ds *ds, const char *name,
                         const char *(*bit_to_string)(uint32_t),
                         uint32_t flags, uint32_t mask);

void flow_format(struct ds *, const struct flow *);
void flow_print(FILE *, const struct flow *);
static inline int flow_compare_3way(const struct flow *, const struct flow *);
static inline bool flow_equal(const struct flow *, const struct flow *);
static inline size_t flow_hash(const struct flow *, uint32_t basis);

void flow_set_dl_vlan(struct flow *, ovs_be16 vid);
void flow_set_vlan_vid(struct flow *, ovs_be16 vid);
void flow_set_vlan_pcp(struct flow *, uint8_t pcp);

int flow_count_mpls_labels(const struct flow *, struct flow_wildcards *);
int flow_count_common_mpls_labels(const struct flow *a, int an,
                                  const struct flow *b, int bn,
                                  struct flow_wildcards *wc);
void flow_push_mpls(struct flow *, int n, ovs_be16 mpls_eth_type,
                    struct flow_wildcards *);
bool flow_pop_mpls(struct flow *, int n, ovs_be16 eth_type,
                   struct flow_wildcards *);
void flow_set_mpls_label(struct flow *, int idx, ovs_be32 label);
void flow_set_mpls_ttl(struct flow *, int idx, uint8_t ttl);
void flow_set_mpls_tc(struct flow *, int idx, uint8_t tc);
void flow_set_mpls_bos(struct flow *, int idx, uint8_t stack);
void flow_set_mpls_lse(struct flow *, int idx, ovs_be32 lse);

void flow_compose(struct dp_packet *, const struct flow *);

static inline uint64_t
flow_get_xreg(const struct flow *flow, int idx)
{
    return ((uint64_t) flow->regs[idx * 2] << 32) | flow->regs[idx * 2 + 1];
}

static inline void
flow_set_xreg(struct flow *flow, int idx, uint64_t value)
{
    flow->regs[idx * 2] = value >> 32;
    flow->regs[idx * 2 + 1] = value;
}

static inline int
flow_compare_3way(const struct flow *a, const struct flow *b)
{
    return memcmp(a, b, sizeof *a);
}

static inline bool
flow_equal(const struct flow *a, const struct flow *b)
{
    return !flow_compare_3way(a, b);
}

static inline size_t
flow_hash(const struct flow *flow, uint32_t basis)
{
    return hash_words64((const uint64_t *)flow,
                        sizeof *flow / sizeof(uint64_t), basis);
}

static inline uint16_t
ofp_to_u16(ofp_port_t ofp_port)
{
    return (OVS_FORCE uint16_t) ofp_port;
}

static inline uint32_t
odp_to_u32(odp_port_t odp_port)
{
    return (OVS_FORCE uint32_t) odp_port;
}

static inline uint32_t
ofp11_to_u32(ofp11_port_t ofp11_port)
{
    return (OVS_FORCE uint32_t) ofp11_port;
}

static inline ofp_port_t
u16_to_ofp(uint16_t port)
{
    return OFP_PORT_C(port);
}

static inline odp_port_t
u32_to_odp(uint32_t port)
{
    return ODP_PORT_C(port);
}

static inline ofp11_port_t
u32_to_ofp11(uint32_t port)
{
    return OFP11_PORT_C(port);
}

static inline uint32_t
hash_ofp_port(ofp_port_t ofp_port)
{
    return hash_int(ofp_to_u16(ofp_port), 0);
}

static inline uint32_t
hash_odp_port(odp_port_t odp_port)
{
    return hash_int(odp_to_u32(odp_port), 0);
}
\f
/* Wildcards for a flow.
 *
 * A 1-bit in each bit in 'masks' indicates that the corresponding bit of
 * the flow is significant (must match).  A 0-bit indicates that the
 * corresponding bit of the flow is wildcarded (need not match). */
struct flow_wildcards {
    struct flow masks;
};

#define WC_MASK_FIELD(WC, FIELD) \
    memset(&(WC)->masks.FIELD, 0xff, sizeof (WC)->masks.FIELD)
#define WC_UNMASK_FIELD(WC, FIELD) \
    memset(&(WC)->masks.FIELD, 0, sizeof (WC)->masks.FIELD)

void flow_wildcards_init_catchall(struct flow_wildcards *);

void flow_wildcards_init_for_packet(struct flow_wildcards *,
                                    const struct flow *);
uint64_t flow_wc_map(const struct flow *);

void flow_wildcards_clear_non_packet_fields(struct flow_wildcards *);

bool flow_wildcards_is_catchall(const struct flow_wildcards *);

void flow_wildcards_set_reg_mask(struct flow_wildcards *,
                                 int idx, uint32_t mask);
void flow_wildcards_set_xreg_mask(struct flow_wildcards *,
                                  int idx, uint64_t mask);

void flow_wildcards_and(struct flow_wildcards *dst,
                        const struct flow_wildcards *src1,
                        const struct flow_wildcards *src2);
void flow_wildcards_or(struct flow_wildcards *dst,
                       const struct flow_wildcards *src1,
                       const struct flow_wildcards *src2);
bool flow_wildcards_has_extra(const struct flow_wildcards *,
                              const struct flow_wildcards *);
uint32_t flow_wildcards_hash(const struct flow_wildcards *, uint32_t basis);
bool flow_wildcards_equal(const struct flow_wildcards *,
                          const struct flow_wildcards *);
uint32_t flow_hash_5tuple(const struct flow *flow, uint32_t basis);
uint32_t flow_hash_symmetric_l4(const struct flow *flow, uint32_t basis);

/* Initialize a flow with random fields that matter for nx_hash_fields. */
void flow_random_hash_fields(struct flow *);
void flow_mask_hash_fields(const struct flow *, struct flow_wildcards *,
                           enum nx_hash_fields);
uint32_t flow_hash_fields(const struct flow *, enum nx_hash_fields,
                          uint16_t basis);
const char *flow_hash_fields_to_str(enum nx_hash_fields);
bool flow_hash_fields_valid(enum nx_hash_fields);

uint32_t flow_hash_in_wildcards(const struct flow *,
                                const struct flow_wildcards *,
                                uint32_t basis);

bool flow_equal_except(const struct flow *a, const struct flow *b,
                       const struct flow_wildcards *);
\f
/* Compressed flow. */

/* Number of 64-bit words present in struct miniflow. */
#define MINI_N_INLINE 4

/* Maximum number of 64-bit words supported. */
BUILD_ASSERT_DECL(FLOW_U64S <= 63);

/* A sparse representation of a "struct flow".
 *
 * A "struct flow" is fairly large and tends to be mostly zeros.  Sparse
 * representation has two advantages.  First, it saves memory.  Second, it
 * saves time when the goal is to iterate over only the nonzero parts of the
 * struct.
 *
 * The 'map' member holds one bit for each uint64_t in a "struct flow".  Each
 * 0-bit indicates that the corresponding uint64_t is zero, each 1-bit that it
 * *may* be nonzero (see below how this applies to minimasks).
 *
 * The 'values_inline' boolean member indicates that the values are at
 * 'inline_values'.  If 'values_inline' is zero, then the values are
 * offline at 'offline_values'.  In either case, values is an array that has
 * one element for each 1-bit in 'map'.  The least-numbered 1-bit is in
 * the first element of the values array, the next 1-bit is in the next array
 * element, and so on.
 *
 * MINI_N_INLINE is the default number of inline words.  When a miniflow is
 * dynamically allocated the actual amount of inline storage may be different.
 * In that case 'inline_values' contains storage at least for the number
 * of words indicated by 'map' (one uint64_t for each 1-bit in the map).
 *
 * Elements in values array are allowed to be zero.  This is useful for "struct
 * minimatch", for which ensuring that the miniflow and minimask members have
 * same 'map' allows optimization.  This allowance applies only to a miniflow
 * that is not a mask.  That is, a minimask may NOT have zero elements in
 * its 'values'.
 */
struct miniflow {
    uint64_t map:63;
    uint64_t values_inline:1;
    union {
        uint64_t *offline_values;
        uint64_t inline_values[MINI_N_INLINE]; /* Minimum inline size. */
    };
};
BUILD_ASSERT_DECL(sizeof(struct miniflow)
                  == sizeof(uint64_t) + MINI_N_INLINE * sizeof(uint64_t));

#define MINIFLOW_VALUES_SIZE(COUNT) ((COUNT) * sizeof(uint64_t))

static inline uint64_t *miniflow_values(struct miniflow *mf)
{
    return OVS_LIKELY(mf->values_inline)
        ? mf->inline_values : mf->offline_values;
}

static inline const uint64_t *miniflow_get_values(const struct miniflow *mf)
{
    return OVS_LIKELY(mf->values_inline)
        ? mf->inline_values : mf->offline_values;
}

/* This is useful for initializing a miniflow for a miniflow_extract() call. */
static inline void miniflow_initialize(struct miniflow *mf,
                                       uint64_t buf[FLOW_U64S])
{
    mf->map = 0;
    mf->values_inline = (buf == (uint64_t *)(mf + 1));
    if (!mf->values_inline) {
        mf->offline_values = buf;
    }
}

struct pkt_metadata;

/* The 'dst->values' must be initialized with a buffer with space for
 * FLOW_U64S.  'dst->map' is ignored on input and set on output to
 * indicate which fields were extracted. */
void miniflow_extract(struct dp_packet *packet, struct miniflow *dst);
void miniflow_init(struct miniflow *, const struct flow *);
void miniflow_init_with_minimask(struct miniflow *, const struct flow *,
                                 const struct minimask *);
void miniflow_clone(struct miniflow *, const struct miniflow *);
void miniflow_clone_inline(struct miniflow *, const struct miniflow *,
                           size_t n_values);
void miniflow_move(struct miniflow *dst, struct miniflow *);
void miniflow_destroy(struct miniflow *);

void miniflow_expand(const struct miniflow *, struct flow *);

static inline uint64_t flow_u64_value(const struct flow *flow, size_t index)
{
    return ((uint64_t *)(flow))[index];
}

static inline uint64_t *flow_u64_lvalue(struct flow *flow, size_t index)
{
    return &((uint64_t *)(flow))[index];
}

static inline bool
flow_get_next_in_map(const struct flow *flow, uint64_t map, uint64_t *value)
{
    if (map) {
        *value = flow_u64_value(flow, raw_ctz(map));
        return true;
    }
    return false;
}

/* Iterate through all flow u64 values specified by 'MAP'. */
#define FLOW_FOR_EACH_IN_MAP(VALUE, FLOW, MAP)         \
    for (uint64_t map__ = (MAP);                       \
         flow_get_next_in_map(FLOW, map__, &(VALUE));  \
         map__ = zero_rightmost_1bit(map__))

/* Iterate through all struct flow u64 indices specified by 'MAP'. */
#define MAP_FOR_EACH_INDEX(U64IDX, MAP)                 \
    for (uint64_t map__ = (MAP);                        \
         map__ && ((U64IDX) = raw_ctz(map__), true);    \
         map__ = zero_rightmost_1bit(map__))

#define FLOW_U64_SIZE(FIELD)                                            \
    DIV_ROUND_UP(sizeof(((struct flow *)0)->FIELD), sizeof(uint64_t))

#define MINIFLOW_MAP(FIELD)                       \
    (((UINT64_C(1) << FLOW_U64_SIZE(FIELD)) - 1)  \
     << (offsetof(struct flow, FIELD) / sizeof(uint64_t)))

struct mf_for_each_in_map_aux {
    const uint64_t *values;
    uint64_t fmap;
    uint64_t map;
};

static inline bool
mf_get_next_in_map(struct mf_for_each_in_map_aux *aux, uint64_t *value)
{
    if (aux->map) {
        uint64_t rm1bit = rightmost_1bit(aux->map);
        aux->map -= rm1bit;

        if (aux->fmap & rm1bit) {
            /* Advance 'aux->values' to point to the value for 'rm1bit'. */
            uint64_t trash = aux->fmap & (rm1bit - 1);
            if (trash) {
                aux->fmap -= trash;
                aux->values += count_1bits(trash);
            }

            /* Retrieve the value for 'rm1bit' then advance past it. */
            aux->fmap -= rm1bit;
            *value = *aux->values++;
        } else {
            *value = 0;
        }
        return true;
    } else {
        return false;
    }
}

/* Iterate through all miniflow u64 values specified by 'MAP'. */
#define MINIFLOW_FOR_EACH_IN_MAP(VALUE, FLOW, MAP)                      \
    for (struct mf_for_each_in_map_aux aux__                            \
             = { miniflow_get_values(FLOW), (FLOW)->map, MAP };         \
         mf_get_next_in_map(&aux__, &(VALUE));                          \
        )

/* This can be used when it is known that 'u64_idx' is set in 'map'. */
static inline uint64_t
miniflow_values_get__(const uint64_t *values, uint64_t map, int u64_idx)
{
    return values[count_1bits(map & ((UINT64_C(1) << u64_idx) - 1))];
}

/* This can be used when it is known that 'u64_idx' is set in
 * the map of 'mf'. */
static inline uint64_t
miniflow_get__(const struct miniflow *mf, int u64_idx)
{
    return miniflow_values_get__(miniflow_get_values(mf), mf->map, u64_idx);
}

/* Get the value of 'FIELD' of an up to 8 byte wide integer type 'TYPE' of
 * a miniflow. */
#define MINIFLOW_GET_TYPE(MF, TYPE, OFS)                                \
    (((MF)->map & (UINT64_C(1) << (OFS) / sizeof(uint64_t)))            \
     ? ((OVS_FORCE const TYPE *)                                        \
        (miniflow_get_values(MF)                                        \
         + count_1bits((MF)->map &                                      \
                       ((UINT64_C(1) << (OFS) / sizeof(uint64_t)) - 1)))) \
     [(OFS) % sizeof(uint64_t) / sizeof(TYPE)]                          \
     : 0)                                                               \

#define MINIFLOW_GET_U8(FLOW, FIELD)                                \
    MINIFLOW_GET_TYPE(FLOW, uint8_t, offsetof(struct flow, FIELD))
#define MINIFLOW_GET_U16(FLOW, FIELD)                               \
    MINIFLOW_GET_TYPE(FLOW, uint16_t, offsetof(struct flow, FIELD))
#define MINIFLOW_GET_BE16(FLOW, FIELD)                              \
    MINIFLOW_GET_TYPE(FLOW, ovs_be16, offsetof(struct flow, FIELD))
#define MINIFLOW_GET_U32(FLOW, FIELD)                               \
    MINIFLOW_GET_TYPE(FLOW, uint32_t, offsetof(struct flow, FIELD))
#define MINIFLOW_GET_BE32(FLOW, FIELD)                              \
    MINIFLOW_GET_TYPE(FLOW, ovs_be32, offsetof(struct flow, FIELD))
#define MINIFLOW_GET_U64(FLOW, FIELD)                               \
    MINIFLOW_GET_TYPE(FLOW, uint64_t, offsetof(struct flow, FIELD))
#define MINIFLOW_GET_BE64(FLOW, FIELD)                              \
    MINIFLOW_GET_TYPE(FLOW, ovs_be64, offsetof(struct flow, FIELD))

static inline uint64_t miniflow_get(const struct miniflow *,
                                    unsigned int u64_ofs);
static inline uint32_t miniflow_get_u32(const struct miniflow *,
                                        unsigned int u32_ofs);
static inline ovs_be32 miniflow_get_be32(const struct miniflow *,
                                         unsigned int be32_ofs);
static inline uint16_t miniflow_get_vid(const struct miniflow *);
static inline uint16_t miniflow_get_tcp_flags(const struct miniflow *);
static inline ovs_be64 miniflow_get_metadata(const struct miniflow *);

bool miniflow_equal(const struct miniflow *a, const struct miniflow *b);
bool miniflow_equal_in_minimask(const struct miniflow *a,
                                const struct miniflow *b,
                                const struct minimask *);
bool miniflow_equal_flow_in_minimask(const struct miniflow *a,
                                     const struct flow *b,
                                     const struct minimask *);
uint32_t miniflow_hash_5tuple(const struct miniflow *flow, uint32_t basis);

\f
/* Compressed flow wildcards. */

/* A sparse representation of a "struct flow_wildcards".
 *
 * See the large comment on struct miniflow for details.
 *
 * Note: While miniflow can have zero data for a 1-bit in the map,
 * a minimask may not!  We rely on this in the implementation. */
struct minimask {
    struct miniflow masks;
};

void minimask_init(struct minimask *, const struct flow_wildcards *);
void minimask_clone(struct minimask *, const struct minimask *);
void minimask_move(struct minimask *dst, struct minimask *src);
void minimask_combine(struct minimask *dst,
                      const struct minimask *a, const struct minimask *b,
                      uint64_t storage[FLOW_U64S]);
void minimask_destroy(struct minimask *);

void minimask_expand(const struct minimask *, struct flow_wildcards *);

static inline uint32_t minimask_get_u32(const struct minimask *,
                                        unsigned int u32_ofs);
static inline ovs_be32 minimask_get_be32(const struct minimask *,
                                         unsigned int be32_ofs);
static inline uint16_t minimask_get_vid_mask(const struct minimask *);
static inline ovs_be64 minimask_get_metadata_mask(const struct minimask *);

bool minimask_equal(const struct minimask *a, const struct minimask *b);
bool minimask_has_extra(const struct minimask *, const struct minimask *);

\f
/* Returns true if 'mask' matches every packet, false if 'mask' fixes any bits
 * or fields. */
static inline bool
minimask_is_catchall(const struct minimask *mask)
{
    /* For every 1-bit in mask's map, the corresponding value is non-zero,
     * so the only way the mask can not fix any bits or fields is for the
     * map the be zero. */
    return mask->masks.map == 0;
}

/* Returns the uint64_t that would be at byte offset '8 * u64_ofs' if 'flow'
 * were expanded into a "struct flow". */
static inline uint64_t miniflow_get(const struct miniflow *flow,
                                    unsigned int u64_ofs)
{
    return flow->map & (UINT64_C(1) << u64_ofs)
        ? miniflow_get__(flow, u64_ofs) : 0;
}

static inline uint32_t miniflow_get_u32(const struct miniflow *flow,
                                        unsigned int u32_ofs)
{
    uint64_t value = miniflow_get(flow, u32_ofs / 2);

#if WORDS_BIGENDIAN
    return (u32_ofs & 1) ? value : value >> 32;
#else
    return (u32_ofs & 1) ? value >> 32 : value;
#endif
}

static inline ovs_be32 miniflow_get_be32(const struct miniflow *flow,
                                         unsigned int be32_ofs)
{
    return (OVS_FORCE ovs_be32)miniflow_get_u32(flow, be32_ofs);
}

/* Returns the VID within the vlan_tci member of the "struct flow" represented
 * by 'flow'. */
static inline uint16_t
miniflow_get_vid(const struct miniflow *flow)
{
    ovs_be16 tci = MINIFLOW_GET_BE16(flow, vlan_tci);
    return vlan_tci_to_vid(tci);
}

/* Returns the uint32_t that would be at byte offset '4 * u32_ofs' if 'mask'
 * were expanded into a "struct flow_wildcards". */
static inline uint32_t
minimask_get_u32(const struct minimask *mask, unsigned int u32_ofs)
{
    return miniflow_get_u32(&mask->masks, u32_ofs);
}

static inline ovs_be32
minimask_get_be32(const struct minimask *mask, unsigned int be32_ofs)
{
    return (OVS_FORCE ovs_be32)minimask_get_u32(mask, be32_ofs);
}

/* Returns the VID mask within the vlan_tci member of the "struct
 * flow_wildcards" represented by 'mask'. */
static inline uint16_t
minimask_get_vid_mask(const struct minimask *mask)
{
    return miniflow_get_vid(&mask->masks);
}

/* Returns the value of the "tcp_flags" field in 'flow'. */
static inline uint16_t
miniflow_get_tcp_flags(const struct miniflow *flow)
{
    return ntohs(MINIFLOW_GET_BE16(flow, tcp_flags));
}

/* Returns the value of the OpenFlow 1.1+ "metadata" field in 'flow'. */
static inline ovs_be64
miniflow_get_metadata(const struct miniflow *flow)
{
    return MINIFLOW_GET_BE64(flow, metadata);
}

/* Returns the mask for the OpenFlow 1.1+ "metadata" field in 'mask'.
 *
 * The return value is all-1-bits if 'mask' matches on the whole value of the
 * metadata field, all-0-bits if 'mask' entirely wildcards the metadata field,
 * or some other value if the metadata field is partially matched, partially
 * wildcarded. */
static inline ovs_be64
minimask_get_metadata_mask(const struct minimask *mask)
{
    return MINIFLOW_GET_BE64(&mask->masks, metadata);
}

/* Perform a bitwise OR of miniflow 'src' flow data with the equivalent
 * fields in 'dst', storing the result in 'dst'. */
static inline void
flow_union_with_miniflow(struct flow *dst, const struct miniflow *src)
{
    uint64_t *dst_u64 = (uint64_t *) dst;
    const uint64_t *p = miniflow_get_values(src);
    int idx;

    MAP_FOR_EACH_INDEX(idx, src->map) {
        dst_u64[idx] |= *p++;
    }
}

static inline void
pkt_metadata_from_flow(struct pkt_metadata *md, const struct flow *flow)
{
    md->recirc_id = flow->recirc_id;
    md->dp_hash = flow->dp_hash;
    md->tunnel = flow->tunnel;
    md->skb_priority = flow->skb_priority;
    md->pkt_mark = flow->pkt_mark;
    md->in_port = flow->in_port;
}

static inline bool is_ip_any(const struct flow *flow)
{
    return dl_type_is_ip_any(flow->dl_type);
}

static inline bool is_icmpv4(const struct flow *flow)
{
    return (flow->dl_type == htons(ETH_TYPE_IP)
            && flow->nw_proto == IPPROTO_ICMP);
}

static inline bool is_icmpv6(const struct flow *flow)
{
    return (flow->dl_type == htons(ETH_TYPE_IPV6)
            && flow->nw_proto == IPPROTO_ICMPV6);
}

static inline bool is_stp(const struct flow *flow)
{
    return (eth_addr_equals(flow->dl_dst, eth_addr_stp)
            && flow->dl_type == htons(FLOW_DL_TYPE_NONE));
}

#endif /* flow.h */