net/openvswitch/datapath.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * Copyright (c) 2007-2014 Nicira, Inc.
   4  */
   5
   6 #ifndef DATAPATH_H
   7 #define DATAPATH_H 1
   8
   9 #include <asm/page.h>
  10 #include <linux/kernel.h>
  11 #include <linux/mutex.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/skbuff.h>
  14 #include <linux/u64_stats_sync.h>
  15 #include <net/ip_tunnels.h>
  16
  17 #include "conntrack.h"
  18 #include "flow.h"
  19 #include "flow_table.h"
  20 #include "meter.h"
  21 #include "vport-internal_dev.h"
  22
  23 #define DP_MAX_PORTS                USHRT_MAX
  24 #define DP_VPORT_HASH_BUCKETS       1024
  25 #define DP_MASKS_REBALANCE_INTERVAL 4000
  26
  27 /**
  28  * struct dp_stats_percpu - per-cpu packet processing statistics for a given
  29  * datapath.
  30  * @n_hit: Number of received packets for which a matching flow was found in
  31  * the flow table.
  32  * @n_miss: Number of received packets that had no matching flow in the flow
  33  * table.  The sum of @n_hit and @n_miss is the number of packets that have
  34  * been received by the datapath.
  35  * @n_lost: Number of received packets that had no matching flow in the flow
  36  * table that could not be sent to userspace (normally due to an overflow in
  37  * one of the datapath's queues).
  38  * @n_mask_hit: Number of masks looked up for flow match.
  39  *   @n_mask_hit / (@n_hit + @n_missed)  will be the average masks looked
  40  *   up per packet.
  41  * @n_cache_hit: The number of received packets that had their mask found using
  42  * the mask cache.
  43  */
  44 struct dp_stats_percpu {
  45         u64 n_hit;
  46         u64 n_missed;
  47         u64 n_lost;
  48         u64 n_mask_hit;
  49         u64 n_cache_hit;
  50         struct u64_stats_sync syncp;
  51 };
  52
  53 /**
  54  * struct datapath - datapath for flow-based packet switching
  55  * @rcu: RCU callback head for deferred destruction.
  56  * @list_node: Element in global 'dps' list.
  57  * @table: flow table.
  58  * @ports: Hash table for ports.  %OVSP_LOCAL port always exists.  Protected by
  59  * ovs_mutex and RCU.
  60  * @stats_percpu: Per-CPU datapath statistics.
  61  * @net: Reference to net namespace.
  62  * @max_headroom: the maximum headroom of all vports in this datapath; it will
  63  * be used by all the internal vports in this dp.
  64  *
  65  * Context: See the comment on locking at the top of datapath.c for additional
  66  * locking information.
  67  */
  68 struct datapath {
  69         struct rcu_head rcu;
  70         struct list_head list_node;
  71
  72         /* Flow table. */
  73         struct flow_table table;
  74
  75         /* Switch ports. */
  76         struct hlist_head *ports;
  77
  78         /* Stats. */
  79         struct dp_stats_percpu __percpu *stats_percpu;
  80
  81         /* Network namespace ref. */
  82         possible_net_t net;
  83
  84         u32 user_features;
  85
  86         u32 max_headroom;
  87
  88         /* Switch meters. */
  89         struct dp_meter_table meter_tbl;
  90 };
  91
  92 /**
  93  * struct ovs_skb_cb - OVS data in skb CB
  94  * @input_vport: The original vport packet came in on. This value is cached
  95  * when a packet is received by OVS.
  96  * @mru: The maximum received fragement size; 0 if the packet is not
  97  * fragmented.
  98  * @acts_origlen: The netlink size of the flow actions applied to this skb.
  99  * @cutlen: The number of bytes from the packet end to be removed.
 100  */
 101 struct ovs_skb_cb {
 102         struct vport            *input_vport;
 103         u16                     mru;
 104         u16                     acts_origlen;
 105         u32                     cutlen;
 106 };
 107 #define OVS_CB(skb) ((struct ovs_skb_cb *)(skb)->cb)
 108
 109 /**
 110  * struct dp_upcall - metadata to include with a packet to send to userspace
 111  * @cmd: One of %OVS_PACKET_CMD_*.
 112  * @userdata: If nonnull, its variable-length value is passed to userspace as
 113  * %OVS_PACKET_ATTR_USERDATA.
 114  * @portid: Netlink portid to which packet should be sent.  If @portid is 0
 115  * then no packet is sent and the packet is accounted in the datapath's @n_lost
 116  * counter.
 117  * @egress_tun_info: If nonnull, becomes %OVS_PACKET_ATTR_EGRESS_TUN_KEY.
 118  * @mru: If not zero, Maximum received IP fragment size.
 119  */
 120 struct dp_upcall_info {
 121         struct ip_tunnel_info *egress_tun_info;
 122         const struct nlattr *userdata;
 123         const struct nlattr *actions;
 124         int actions_len;
 125         u32 portid;
 126         u8 cmd;
 127         u16 mru;
 128 };
 129
 130 /**
 131  * struct ovs_net - Per net-namespace data for ovs.
 132  * @dps: List of datapaths to enable dumping them all out.
 133  * Protected by genl_mutex.
 134  */
 135 struct ovs_net {
 136         struct list_head dps;
 137         struct work_struct dp_notify_work;
 138         struct delayed_work masks_rebalance;
 139 #if     IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
 140         struct ovs_ct_limit_info *ct_limit_info;
 141 #endif
 142
 143         /* Module reference for configuring conntrack. */
 144         bool xt_label;
 145 };
 146
 147 /**
 148  * enum ovs_pkt_hash_types - hash info to include with a packet
 149  * to send to userspace.
 150  * @OVS_PACKET_HASH_SW_BIT: indicates hash was computed in software stack.
 151  * @OVS_PACKET_HASH_L4_BIT: indicates hash is a canonical 4-tuple hash
 152  * over transport ports.
 153  */
 154 enum ovs_pkt_hash_types {
 155         OVS_PACKET_HASH_SW_BIT = (1ULL << 32),
 156         OVS_PACKET_HASH_L4_BIT = (1ULL << 33),
 157 };
 158
 159 extern unsigned int ovs_net_id;
 160 void ovs_lock(void);
 161 void ovs_unlock(void);
 162
 163 #ifdef CONFIG_LOCKDEP
 164 int lockdep_ovsl_is_held(void);
 165 #else
 166 #define lockdep_ovsl_is_held()  1
 167 #endif
 168
 169 #define ASSERT_OVSL()           WARN_ON(!lockdep_ovsl_is_held())
 170 #define ovsl_dereference(p)                                     \
 171         rcu_dereference_protected(p, lockdep_ovsl_is_held())
 172 #define rcu_dereference_ovsl(p)                                 \
 173         rcu_dereference_check(p, lockdep_ovsl_is_held())
 174
 175 static inline struct net *ovs_dp_get_net(const struct datapath *dp)
 176 {
 177         return read_pnet(&dp->net);
 178 }
 179
 180 static inline void ovs_dp_set_net(struct datapath *dp, struct net *net)
 181 {
 182         write_pnet(&dp->net, net);
 183 }
 184
 185 struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no);
 186
 187 static inline struct vport *ovs_vport_rcu(const struct datapath *dp, int port_no)
 188 {
 189         WARN_ON_ONCE(!rcu_read_lock_held());
 190         return ovs_lookup_vport(dp, port_no);
 191 }
 192
 193 static inline struct vport *ovs_vport_ovsl_rcu(const struct datapath *dp, int port_no)
 194 {
 195         WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
 196         return ovs_lookup_vport(dp, port_no);
 197 }
 198
 199 static inline struct vport *ovs_vport_ovsl(const struct datapath *dp, int port_no)
 200 {
 201         ASSERT_OVSL();
 202         return ovs_lookup_vport(dp, port_no);
 203 }
 204
 205 /* Must be called with rcu_read_lock. */
 206 static inline struct datapath *get_dp_rcu(struct net *net, int dp_ifindex)
 207 {
 208         struct net_device *dev = dev_get_by_index_rcu(net, dp_ifindex);
 209
 210         if (dev) {
 211                 struct vport *vport = ovs_internal_dev_get_vport(dev);
 212
 213                 if (vport)
 214                         return vport->dp;
 215         }
 216
 217         return NULL;
 218 }
 219
 220 /* The caller must hold either ovs_mutex or rcu_read_lock to keep the
 221  * returned dp pointer valid.
 222  */
 223 static inline struct datapath *get_dp(struct net *net, int dp_ifindex)
 224 {
 225         struct datapath *dp;
 226
 227         WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_ovsl_is_held());
 228         rcu_read_lock();
 229         dp = get_dp_rcu(net, dp_ifindex);
 230         rcu_read_unlock();
 231
 232         return dp;
 233 }
 234
 235 extern struct notifier_block ovs_dp_device_notifier;
 236 extern struct genl_family dp_vport_genl_family;
 237
 238 DECLARE_STATIC_KEY_FALSE(tc_recirc_sharing_support);
 239
 240 void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key);
 241 void ovs_dp_detach_port(struct vport *);
 242 int ovs_dp_upcall(struct datapath *, struct sk_buff *,
 243                   const struct sw_flow_key *, const struct dp_upcall_info *,
 244                   uint32_t cutlen);
 245
 246 const char *ovs_dp_name(const struct datapath *dp);
 247 struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, struct net *net,
 248                                          u32 portid, u32 seq, u8 cmd);
 249
 250 int ovs_execute_actions(struct datapath *dp, struct sk_buff *skb,
 251                         const struct sw_flow_actions *, struct sw_flow_key *);
 252
 253 void ovs_dp_notify_wq(struct work_struct *work);
 254
 255 int action_fifos_init(void);
 256 void action_fifos_exit(void);
 257
 258 /* 'KEY' must not have any bits set outside of the 'MASK' */
 259 #define OVS_MASKED(OLD, KEY, MASK) ((KEY) | ((OLD) & ~(MASK)))
 260 #define OVS_SET_MASKED(OLD, KEY, MASK) ((OLD) = OVS_MASKED(OLD, KEY, MASK))
 261
 262 #define OVS_NLERR(logging_allowed, fmt, ...)                    \
 263 do {                                                            \
 264         if (logging_allowed && net_ratelimit())                 \
 265                 pr_info("netlink: " fmt "\n", ##__VA_ARGS__);   \
 266 } while (0)
 267 #endif /* datapath.h */