linux/net/openvswitch/flow.h
Jarno Rajahalme 1139e241ec openvswitch: Compact sw_flow_key.
Minimize padding in sw_flow_key and move 'tp' top the main struct.
These changes simplify code when accessing the transport port numbers
and the tcp flags, and makes the sw_flow_key 8 bytes smaller on 64-bit
systems (128->120 bytes).  These changes also make the keys for IPv4
packets to fit in one cache line.

There is a valid concern for safety of packing the struct
ovs_key_ipv4_tunnel, as it would be possible to take the address of
the tun_id member as a __be64 * which could result in unaligned access
in some systems. However:

- sw_flow_key itself is 64-bit aligned, so the tun_id within is
  always
  64-bit aligned.
- We never make arrays of ovs_key_ipv4_tunnel (which would force
  every
  second tun_key to be misaligned).
- We never take the address of the tun_id in to a __be64 *.
- Whereever we use struct ovs_key_ipv4_tunnel outside the
  sw_flow_key,
  it is in stack (on tunnel input functions), where compiler has full
  control of the alignment.

Signed-off-by: Jarno Rajahalme <jrajahalme@nicira.com>
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
2014-05-22 16:27:34 -07:00

192 lines
5.7 KiB
C

/*
* Copyright (c) 2007-2013 Nicira, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*/
#ifndef FLOW_H
#define FLOW_H 1
#include <linux/cache.h>
#include <linux/kernel.h>
#include <linux/netlink.h>
#include <linux/openvswitch.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#include <linux/rcupdate.h>
#include <linux/if_ether.h>
#include <linux/in6.h>
#include <linux/jiffies.h>
#include <linux/time.h>
#include <linux/flex_array.h>
#include <net/inet_ecn.h>
struct sk_buff;
/* Used to memset ovs_key_ipv4_tunnel padding. */
#define OVS_TUNNEL_KEY_SIZE \
(offsetof(struct ovs_key_ipv4_tunnel, ipv4_ttl) + \
FIELD_SIZEOF(struct ovs_key_ipv4_tunnel, ipv4_ttl))
struct ovs_key_ipv4_tunnel {
__be64 tun_id;
__be32 ipv4_src;
__be32 ipv4_dst;
__be16 tun_flags;
u8 ipv4_tos;
u8 ipv4_ttl;
} __packed __aligned(4); /* Minimize padding. */
static inline void ovs_flow_tun_key_init(struct ovs_key_ipv4_tunnel *tun_key,
const struct iphdr *iph, __be64 tun_id,
__be16 tun_flags)
{
tun_key->tun_id = tun_id;
tun_key->ipv4_src = iph->saddr;
tun_key->ipv4_dst = iph->daddr;
tun_key->ipv4_tos = iph->tos;
tun_key->ipv4_ttl = iph->ttl;
tun_key->tun_flags = tun_flags;
/* clear struct padding. */
memset((unsigned char *) tun_key + OVS_TUNNEL_KEY_SIZE, 0,
sizeof(*tun_key) - OVS_TUNNEL_KEY_SIZE);
}
struct sw_flow_key {
struct ovs_key_ipv4_tunnel tun_key; /* Encapsulating tunnel key. */
struct {
u32 priority; /* Packet QoS priority. */
u32 skb_mark; /* SKB mark. */
u16 in_port; /* Input switch port (or DP_MAX_PORTS). */
} __packed phy; /* Safe when right after 'tun_key'. */
struct {
u8 src[ETH_ALEN]; /* Ethernet source address. */
u8 dst[ETH_ALEN]; /* Ethernet destination address. */
__be16 tci; /* 0 if no VLAN, VLAN_TAG_PRESENT set otherwise. */
__be16 type; /* Ethernet frame type. */
} eth;
struct {
u8 proto; /* IP protocol or lower 8 bits of ARP opcode. */
u8 tos; /* IP ToS. */
u8 ttl; /* IP TTL/hop limit. */
u8 frag; /* One of OVS_FRAG_TYPE_*. */
} ip;
struct {
__be16 src; /* TCP/UDP/SCTP source port. */
__be16 dst; /* TCP/UDP/SCTP destination port. */
__be16 flags; /* TCP flags. */
} tp;
union {
struct {
struct {
__be32 src; /* IP source address. */
__be32 dst; /* IP destination address. */
} addr;
struct {
u8 sha[ETH_ALEN]; /* ARP source hardware address. */
u8 tha[ETH_ALEN]; /* ARP target hardware address. */
} arp;
} ipv4;
struct {
struct {
struct in6_addr src; /* IPv6 source address. */
struct in6_addr dst; /* IPv6 destination address. */
} addr;
__be32 label; /* IPv6 flow label. */
struct {
struct in6_addr target; /* ND target address. */
u8 sll[ETH_ALEN]; /* ND source link layer address. */
u8 tll[ETH_ALEN]; /* ND target link layer address. */
} nd;
} ipv6;
};
} __aligned(BITS_PER_LONG/8); /* Ensure that we can do comparisons as longs. */
struct sw_flow_key_range {
unsigned short int start;
unsigned short int end;
};
struct sw_flow_mask {
int ref_count;
struct rcu_head rcu;
struct list_head list;
struct sw_flow_key_range range;
struct sw_flow_key key;
};
struct sw_flow_match {
struct sw_flow_key *key;
struct sw_flow_key_range range;
struct sw_flow_mask *mask;
};
struct sw_flow_actions {
struct rcu_head rcu;
u32 actions_len;
struct nlattr actions[];
};
struct flow_stats {
u64 packet_count; /* Number of packets matched. */
u64 byte_count; /* Number of bytes matched. */
unsigned long used; /* Last used time (in jiffies). */
spinlock_t lock; /* Lock for atomic stats update. */
__be16 tcp_flags; /* Union of seen TCP flags. */
};
struct sw_flow {
struct rcu_head rcu;
struct hlist_node hash_node[2];
u32 hash;
int stats_last_writer; /* NUMA-node id of the last writer on
* 'stats[0]'.
*/
struct sw_flow_key key;
struct sw_flow_key unmasked_key;
struct sw_flow_mask *mask;
struct sw_flow_actions __rcu *sf_acts;
struct flow_stats __rcu *stats[]; /* One for each NUMA node. First one
* is allocated at flow creation time,
* the rest are allocated on demand
* while holding the 'stats[0].lock'.
*/
};
struct arp_eth_header {
__be16 ar_hrd; /* format of hardware address */
__be16 ar_pro; /* format of protocol address */
unsigned char ar_hln; /* length of hardware address */
unsigned char ar_pln; /* length of protocol address */
__be16 ar_op; /* ARP opcode (command) */
/* Ethernet+IPv4 specific members. */
unsigned char ar_sha[ETH_ALEN]; /* sender hardware address */
unsigned char ar_sip[4]; /* sender IP address */
unsigned char ar_tha[ETH_ALEN]; /* target hardware address */
unsigned char ar_tip[4]; /* target IP address */
} __packed;
void ovs_flow_stats_update(struct sw_flow *flow, struct sk_buff *skb);
void ovs_flow_stats_get(struct sw_flow *flow, struct ovs_flow_stats *stats,
unsigned long *used, __be16 *tcp_flags);
void ovs_flow_stats_clear(struct sw_flow *flow);
u64 ovs_flow_used_time(unsigned long flow_jiffies);
int ovs_flow_extract(struct sk_buff *, u16 in_port, struct sw_flow_key *);
#endif /* flow.h */