text: /*
   * Copyright (c) 2007-2014 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
   */
  
  #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/if_arp.h>
  #include <linux/if_vlan.h>
  #include <linux/in.h>
  #include <linux/ip.h>
  #include <linux/jhash.h>
  #include <linux/delay.h>
  #include <linux/time.h>
  #include <linux/etherdevice.h>
  #include <linux/genetlink.h>
  #include <linux/kernel.h>
  #include <linux/kthread.h>
  #include <linux/mutex.h>
  #include <linux/percpu.h>
  #include <linux/rcupdate.h>
  #include <linux/tcp.h>
  #include <linux/udp.h>
  #include <linux/ethtool.h>
  #include <linux/wait.h>
  #include <asm/div64.h>
  #include <linux/highmem.h>
  #include <linux/netfilter_bridge.h>
  #include <linux/netfilter_ipv4.h>
  #include <linux/inetdevice.h>
  #include <linux/list.h>
  #include <linux/openvswitch.h>
  #include <linux/rculist.h>
  #include <linux/dmi.h>
  #include <net/genetlink.h>
  #include <net/net_namespace.h>
  #include <net/netns/generic.h>
  
  #include "datapath.h"
  #include "flow.h"
  #include "flow_table.h"
  #include "flow_netlink.h"
  #include "meter.h"
  #include "vport-internal_dev.h"
  #include "vport-netdev.h"
  
  unsigned int ovs_net_id __read_mostly;
  
  static struct genl_family dp_packet_genl_family;
  static struct genl_family dp_flow_genl_family;
  static struct genl_family dp_datapath_genl_family;
  
  static const struct nla_policy flow_policy[];
  
  static const struct genl_multicast_group ovs_dp_flow_multicast_group = {
  	.name = OVS_FLOW_MCGROUP,
  };
  
  static const struct genl_multicast_group ovs_dp_datapath_multicast_group = {
  	.name = OVS_DATAPATH_MCGROUP,
  };
  
  static const struct genl_multicast_group ovs_dp_vport_multicast_group = {
  	.name = OVS_VPORT_MCGROUP,
  };
  
  /* Check if need to build a reply message.
   * OVS userspace sets the NLM_F_ECHO flag if it needs the reply. */
  static bool ovs_must_notify(struct genl_family *family, struct genl_info *info,
  			    unsigned int group)
  {
  	return info->nlhdr->nlmsg_flags & NLM_F_ECHO ||
  	       genl_has_listeners(family, genl_info_net(info), group);
  }
  
  static void ovs_notify(struct genl_family *family,
  		       struct sk_buff *skb, struct genl_info *info)
  {
  	genl_notify(family, skb, info, 0, GFP_KERNEL);
  }
  
  /**
   * DOC: Locking:
   *
   * All writes e.g. Writes to device state (add/remove datapath, port, set
   * operations on vports, etc.), Writes to other state (flow table
   * modifications, set miscellaneous datapath parameters, etc.) are protected
   * by ovs_lock.
   *
   * Reads are protected by RCU.
   *
   * There are a few special cases (mostly stats) that have their own
   * synchronization but they nest under all of above and don't interact with
   * each other.
   *
   * The RTNL lock nests inside ovs_mutex.
   */
  
  static DEFINE_MUTEX(ovs_mutex);
  
  void ovs_lock(void)
  {
  	mutex_lock(&ovs_mutex);
  }
  
  void ovs_unlock(void)
  {
  	mutex_unlock(&ovs_mutex);
  }
  
  #ifdef CONFIG_LOCKDEP
  int lockdep_ovsl_is_held(void)
  {
  	if (debug_locks)
  		return lockdep_is_held(&ovs_mutex);
  	else
  		return 1;
  }
  #endif
  
  static struct vport *new_vport(const struct vport_parms *);
  static int queue_gso_packets(struct datapath *dp, struct sk_buff *,
  			     const struct sw_flow_key *,
  			     const struct dp_upcall_info *,
  			     uint32_t cutlen);
  static int queue_userspace_packet(struct datapath *dp, struct sk_buff *,
  				  const struct sw_flow_key *,
  				  const struct dp_upcall_info *,
  				  uint32_t cutlen);
  
  /* Must be called with rcu_read_lock or ovs_mutex. */
  const char *ovs_dp_name(const struct datapath *dp)
  {
  	struct vport *vport = ovs_vport_ovsl_rcu(dp, OVSP_LOCAL);
  	return ovs_vport_name(vport);
  }
  
  static int get_dpifindex(const struct datapath *dp)
  {
  	struct vport *local;
  	int ifindex;
  
  	rcu_read_lock();
  
  	local = ovs_vport_rcu(dp, OVSP_LOCAL);
  	if (local)
  		ifindex = local->dev->ifindex;
  	else
  		ifindex = 0;
  
  	rcu_read_unlock();
  
  	return ifindex;
  }
  
  static void destroy_dp_rcu(struct rcu_head *rcu)
  {
  	struct datapath *dp = container_of(rcu, struct datapath, rcu);
  
  	ovs_flow_tbl_destroy(&dp->table);
  	free_percpu(dp->stats_percpu);
  	kfree(dp->ports);
  	ovs_meters_exit(dp);
  	kfree(dp);
  }
  
  static struct hlist_head *vport_hash_bucket(const struct datapath *dp,
  					    u16 port_no)
  {
  	return &dp->ports[port_no & (DP_VPORT_HASH_BUCKETS - 1)];
  }
  
  /* Called with ovs_mutex or RCU read lock. */
  struct vport *ovs_lookup_vport(const struct datapath *dp, u16 port_no)
  {
  	struct vport *vport;
  	struct hlist_head *head;
  
  	head = vport_hash_bucket(dp, port_no);
  	hlist_for_each_entry_rcu(vport, head, dp_hash_node) {
  		if (vport->port_no == port_no)
  			return vport;
  	}
  	return NULL;
  }
  
  /* Called with ovs_mutex. */
  static struct vport *new_vport(const struct vport_parms *parms)
  {
  	struct vport *vport;
  
  	vport = ovs_vport_add(parms);
  	if (!IS_ERR(vport)) {
  		struct datapath *dp = parms->dp;
  		struct hlist_head *head = vport_hash_bucket(dp, vport->port_no);
  
  		hlist_add_head_rcu(&vport->dp_hash_node, head);
  	}
  	return vport;
  }
  
  void ovs_dp_detach_port(struct vport *p)
  {
  	ASSERT_OVSL();
  
  	/* First drop references to device. */
  	hlist_del_rcu(&p->dp_hash_node);
  
  	/* Then destroy it. */
  	ovs_vport_del(p);
  }
  
  /* Must be called with rcu_read_lock. */
  void ovs_dp_process_packet(struct sk_buff *skb, struct sw_flow_key *key)
  {
  	const struct vport *p = OVS_CB(skb)->input_vport;
  	struct datapath *dp = p->dp;
  	struct sw_flow *flow;
  	struct sw_flow_actions *sf_acts;
  	struct dp_stats_percpu *stats;
  	u64 *stats_counter;
  	u32 n_mask_hit;
  
  	stats = this_cpu_ptr(dp->stats_percpu);
  
  	/* Look up flow. */
  	flow = ovs_flow_tbl_lookup_stats(&dp->table, key, &n_mask_hit);
  	if (unlikely(!flow)) {
  		struct dp_upcall_info upcall;
  		int error;
  
  		memset(&upcall, 0, sizeof(upcall));
  		upcall.cmd = OVS_PACKET_CMD_MISS;
  		upcall.portid = ovs_vport_find_upcall_portid(p, skb);
  		upcall.mru = OVS_CB(skb)->mru;
  		error = ovs_dp_upcall(dp, skb, key, &upcall, 0);
  		if (unlikely(error))
  			kfree_skb(skb);
  		else
  			consume_skb(skb);
  		stats_counter = &stats->n_missed;
  		goto out;
  	}
  
  	ovs_flow_stats_update(flow, key->tp.flags, skb);
  	sf_acts = rcu_dereference(flow->sf_acts);
  	ovs_execute_actions(dp, skb, sf_acts, key);
  
  	stats_counter = &stats->n_hit;
  
  out:
  	/* Update datapath statistics. */
  	u64_stats_update_begin(&stats->syncp);
  	(*stats_counter)++;
  	stats->n_mask_hit += n_mask_hit;
  	u64_stats_update_end(&stats->syncp);
  }
  
  int ovs_dp_upcall(struct datapath *dp, struct sk_buff *skb,
  		  const struct sw_flow_key *key,
  		  const struct dp_upcall_info *upcall_info,
  		  uint32_t cutlen)
  {
  	struct dp_stats_percpu *stats;
  	int err;
  
  	if (upcall_info->portid == 0) {
  		err = -ENOTCONN;
  		goto err;
  	}
  
  	if (!skb_is_gso(skb))
  		err = queue_userspace_packet(dp, skb, key, upcall_info, cutlen);
  	else
  		err = queue_gso_packets(dp, skb, key, upcall_info, cutlen);
  	if (err)
  		goto err;
  
  	return 0;
  
  err:
  	stats = this_cpu_ptr(dp->stats_percpu);
  
  	u64_stats_update_begin(&stats->syncp);
  	stats->n_lost++;
  	u64_stats_update_end(&stats->syncp);
  
  	return err;
  }
  
  static int queue_gso_packets(struct datapath *dp, struct sk_buff *skb,
  			     const struct sw_flow_key *key,
  			     const struct dp_upcall_info *upcall_info,
  				 uint32_t cutlen)
  {
  	unsigned int gso_type = skb_shinfo(skb)->gso_type;
  	struct sw_flow_key later_key;
  	struct sk_buff *segs, *nskb;
  	int err;
  
  	BUILD_BUG_ON(sizeof(*OVS_CB(skb)) > SKB_SGO_CB_OFFSET);
  	segs = __skb_gso_segment(skb, NETIF_F_SG, false);
  	if (IS_ERR(segs))
  		return PTR_ERR(segs);
  	if (segs == NULL)
  		return -EINVAL;
  
  	if (gso_type & SKB_GSO_UDP) {
  		/* The initial flow key extracted by ovs_flow_key_extract()
  		 * in this case is for a first fragment, so we need to
  		 * properly mark later fragments.
  		 */
  		later_key = *key;
  		later_key.ip.frag = OVS_FRAG_TYPE_LATER;
  	}
  
  	/* Queue all of the segments. */
  	skb = segs;
  	do {
  		if (gso_type & SKB_GSO_UDP && skb != segs)
  			key = &later_key;
  
  		err = queue_userspace_packet(dp, skb, key, upcall_info, cutlen);
  		if (err)
  			break;
  
  	} while ((skb = skb->next));
  
  	/* Free all of the segments. */
  	skb = segs;
  	do {
  		nskb = skb->next;
  		if (err)
  			kfree_skb(skb);
  		else
  			consume_skb(skb);
  	} while ((skb = nskb));
  	return err;
  }
  
  static size_t upcall_msg_size(const struct dp_upcall_info *upcall_info,
  			      unsigned int hdrlen, int actions_attrlen)
  {
  	size_t size = NLMSG_ALIGN(sizeof(struct ovs_header))
  		+ nla_total_size(hdrlen) /* OVS_PACKET_ATTR_PACKET */
  		+ nla_total_size(ovs_key_attr_size()) /* OVS_PACKET_ATTR_KEY */
  		+ nla_total_size(sizeof(unsigned int)); /* OVS_PACKET_ATTR_LEN */
  
  	/* OVS_PACKET_ATTR_USERDATA */
  	if (upcall_info->userdata)
  		size += NLA_ALIGN(upcall_info->userdata->nla_len);
  
  	/* OVS_PACKET_ATTR_EGRESS_TUN_KEY */
  	if (upcall_info->egress_tun_info)
  		size += nla_total_size(ovs_tun_key_attr_size());
  
  	/* OVS_PACKET_ATTR_ACTIONS */
  	if (upcall_info->actions_len)
  		size += nla_total_size(actions_attrlen);
  
  	/* OVS_PACKET_ATTR_MRU */
  	if (upcall_info->mru)
  		size += nla_total_size(sizeof(upcall_info->mru));
  
  	return size;
  }
  
  static void pad_packet(struct datapath *dp, struct sk_buff *skb)
  {
  	if (!(dp->user_features & OVS_DP_F_UNALIGNED)) {
  		size_t plen = NLA_ALIGN(skb->len) - skb->len;
  
  		if (plen > 0)
  			skb_put_zero(skb, plen);
  	}
  }
  
  static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
  				  const struct sw_flow_key *key,
  				  const struct dp_upcall_info *upcall_info,
  				  uint32_t cutlen)
  {
  	struct ovs_header *upcall;
  	struct sk_buff *nskb = NULL;
  	struct sk_buff *user_skb = NULL; /* to be queued to userspace */
  	struct nlattr *nla;
  	size_t len;
  	unsigned int hlen;
  	int err, dp_ifindex;
  
  	dp_ifindex = get_dpifindex(dp);
  	if (!dp_ifindex)
  		return -ENODEV;
  
  	if (skb_vlan_tag_present(skb)) {
  		nskb = skb_clone(skb, GFP_ATOMIC);
  		if (!nskb)
  			return -ENOMEM;
  
  		nskb = __vlan_hwaccel_push_inside(nskb);
  		if (!nskb)
  			return -ENOMEM;
  
  		skb = nskb;
  	}
  
  	if (nla_attr_size(skb->len) > USHRT_MAX) {
  		err = -EFBIG;
  		goto out;
  	}
  
  	/* Complete checksum if needed */
  	if (skb->ip_summed == CHECKSUM_PARTIAL &&
  	    (err = skb_csum_hwoffload_help(skb, 0)))
  		goto out;
  
  	/* Older versions of OVS user space enforce alignment of the last
  	 * Netlink attribute to NLA_ALIGNTO which would require extensive
  	 * padding logic. Only perform zerocopy if padding is not required.
  	 */
  	if (dp->user_features & OVS_DP_F_UNALIGNED)
  		hlen = skb_zerocopy_headlen(skb);
  	else
  		hlen = skb->len;
  
  	len = upcall_msg_size(upcall_info, hlen - cutlen,
  			      OVS_CB(skb)->acts_origlen);
  	user_skb = genlmsg_new(len, GFP_ATOMIC);
  	if (!user_skb) {
  		err = -ENOMEM;
  		goto out;
  	}
  
  	upcall = genlmsg_put(user_skb, 0, 0, &dp_packet_genl_family,
  			     0, upcall_info->cmd);
  	upcall->dp_ifindex = dp_ifindex;
  
  	err = ovs_nla_put_key(key, key, OVS_PACKET_ATTR_KEY, false, user_skb);
  	BUG_ON(err);
  
  	if (upcall_info->userdata)
  		__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
  			  nla_len(upcall_info->userdata),
  			  nla_data(upcall_info->userdata));
  
  	if (upcall_info->egress_tun_info) {
  		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_EGRESS_TUN_KEY);
  		err = ovs_nla_put_tunnel_info(user_skb,
  					      upcall_info->egress_tun_info);
  		BUG_ON(err);
  		nla_nest_end(user_skb, nla);
  	}
  
  	if (upcall_info->actions_len) {
  		nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_ACTIONS);
  		err = ovs_nla_put_actions(upcall_info->actions,
  					  upcall_info->actions_len,
  					  user_skb);
  		if (!err)
  			nla_nest_end(user_skb, nla);
  		else
  			nla_nest_cancel(user_skb, nla);
  	}
  
  	/* Add OVS_PACKET_ATTR_MRU */
  	if (upcall_info->mru) {
  		if (nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU,
  				upcall_info->mru)) {
  			err = -ENOBUFS;
  			goto out;
  		}
  		pad_packet(dp, user_skb);
  	}
  
  	/* Add OVS_PACKET_ATTR_LEN when packet is truncated */
  	if (cutlen > 0) {
  		if (nla_put_u32(user_skb, OVS_PACKET_ATTR_LEN,
  				skb->len)) {
  			err = -ENOBUFS;
  			goto out;
  		}
  		pad_packet(dp, user_skb);
  	}
  
  	/* Only reserve room for attribute header, packet data is added
  	 * in skb_zerocopy() */
  	if (!(nla = nla_reserve(user_skb, OVS_PACKET_ATTR_PACKET, 0))) {
  		err = -ENOBUFS;
  		goto out;
  	}
  	nla->nla_len = nla_attr_size(skb->len - cutlen);
  
  	err = skb_zerocopy(user_skb, skb, skb->len - cutlen, hlen);
  	if (err)
  		goto out;
  
  	/* Pad OVS_PACKET_ATTR_PACKET if linear copy was performed */
  	pad_packet(dp, user_skb);
  
  	((struct nlmsghdr *) user_skb->data)->nlmsg_len = user_skb->len;
  
  	err = genlmsg_unicast(ovs_dp_get_net(dp), user_skb, upcall_info->portid);
  	user_skb = NULL;
  out:
  	if (err)
  		skb_tx_error(skb);
  	kfree_skb(user_skb);
  	kfree_skb(nskb);
  	return err;
  }
  
  static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)
  {
  	struct ovs_header *ovs_header = info->userhdr;
  	struct net *net = sock_net(skb->sk);
  	struct nlattr **a = info->attrs;
  	struct sw_flow_actions *acts;
  	struct sk_buff *packet;
  	struct sw_flow *flow;
  	struct sw_flow_actions *sf_acts;
  	struct datapath *dp;
  	struct vport *input_vport;
  	u16 mru = 0;
  	int len;
  	int err;
  	bool log = !a[OVS_PACKET_ATTR_PROBE];
  
  	err = -EINVAL;
  	if (!a[OVS_PACKET_ATTR_PACKET] || !a[OVS_PACKET_ATTR_KEY] ||
  	    !a[OVS_PACKET_ATTR_ACTIONS])
  		goto err;
  
  	len = nla_len(a[OVS_PACKET_ATTR_PACKET]);
  	packet = __dev_alloc_skb(NET_IP_ALIGN + len, GFP_KERNEL);
  	err = -ENOMEM;
  	if (!packet)
  		goto err;
  	skb_reserve(packet, NET_IP_ALIGN);
  
  	nla_memcpy(__skb_put(packet, len), a[OVS_PACKET_ATTR_PACKET], len);
  
  	/* Set packet's mru */
  	if (a[OVS_PACKET_ATTR_MRU]) {
  		mru = nla_get_u16(a[OVS_PACKET_ATTR_MRU]);
  		packet->ignore_df = 1;
  	}
  	OVS_CB(packet)->mru = mru;
  
  	/* Build an sw_flow for sending this packet. */
  	flow = ovs_flow_alloc();
  	err = PTR_ERR(flow);
  	if (IS_ERR(flow))
  		goto err_kfree_skb;
  
  	err = ovs_flow_key_extract_userspace(net, a[OVS_PACKET_ATTR_KEY],
  					     packet, &flow->key, log);
  	if (err)
  		goto err_flow_free;
  
  	err = ovs_nla_copy_actions(net, a[OVS_PACKET_ATTR_ACTIONS],
  				   &flow->key, &acts, log);
  	if (err)
  		goto err_flow_free;
  
  	rcu_assign_pointer(flow->sf_acts, acts);
  	packet->priority = flow->key.phy.priority;
  	packet->mark = flow->key.phy.skb_mark;
  
  	rcu_read_lock();
  	dp = get_dp_rcu(net, ovs_header->dp_ifindex);
  	err = -ENODEV;
  	if (!dp)
  		goto err_unlock;
  
  	input_vport = ovs_vport_rcu(dp, flow->key.phy.in_port);
  	if (!input_vport)
  		input_vport = ovs_vport_rcu(dp, OVSP_LOCAL);
  
  	if (!input_vport)
  		goto err_unlock;
  
  	packet->dev = input_vport->dev;
  	OVS_CB(packet)->input_vport = input_vport;
  	sf_acts = rcu_dereference(flow->sf_acts);
  
  	local_bh_disable();
  	err = ovs_execute_actions(dp, packet, sf_acts, &flow->key);
  	local_bh_enable();
  	rcu_read_unlock();
  
  	ovs_flow_free(flow, false);
  	return err;
  
  err_unlock:
  	rcu_read_unlock();
  err_flow_free:
  	ovs_flow_free(flow, false);
  err_kfree_skb:
  	kfree_skb(packet);
  err:
  	return err;
  }
  
  static const struct nla_policy packet_policy[OVS_PACKET_ATTR_MAX + 1] = {
  	[OVS_PACKET_ATTR_PACKET] = { .len = ETH_HLEN },
  	[OVS_PACKET_ATTR_KEY] = { .type = NLA_NESTED },
  	[OVS_PACKET_ATTR_ACTIONS] = { .type = NLA_NESTED },
  	[OVS_PACKET_ATTR_PROBE] = { .type = NLA_FLAG },
  	[OVS_PACKET_ATTR_MRU] = { .type = NLA_U16 },
  };
  
  static const struct genl_ops dp_packet_genl_ops[] = {
  	{ .cmd = OVS_PACKET_CMD_EXECUTE,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = packet_policy,
  	  .doit = ovs_packet_cmd_execute
  	}
  };
  
  static struct genl_family dp_packet_genl_family __ro_after_init = {
  	.hdrsize = sizeof(struct ovs_header),
  	.name = OVS_PACKET_FAMILY,
  	.version = OVS_PACKET_VERSION,
  	.maxattr = OVS_PACKET_ATTR_MAX,
  	.netnsok = true,
  	.parallel_ops = true,
  	.ops = dp_packet_genl_ops,
  	.n_ops = ARRAY_SIZE(dp_packet_genl_ops),
  	.module = THIS_MODULE,
  };
  
  static void get_dp_stats(const struct datapath *dp, struct ovs_dp_stats *stats,
  			 struct ovs_dp_megaflow_stats *mega_stats)
  {
  	int i;
  
  	memset(mega_stats, 0, sizeof(*mega_stats));
  
  	stats->n_flows = ovs_flow_tbl_count(&dp->table);
  	mega_stats->n_masks = ovs_flow_tbl_num_masks(&dp->table);
  
  	stats->n_hit = stats->n_missed = stats->n_lost = 0;
  
  	for_each_possible_cpu(i) {
  		const struct dp_stats_percpu *percpu_stats;
  		struct dp_stats_percpu local_stats;
  		unsigned int start;
  
  		percpu_stats = per_cpu_ptr(dp->stats_percpu, i);
  
  		do {
  			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
  			local_stats = *percpu_stats;
  		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
  
  		stats->n_hit += local_stats.n_hit;
  		stats->n_missed += local_stats.n_missed;
  		stats->n_lost += local_stats.n_lost;
  		mega_stats->n_mask_hit += local_stats.n_mask_hit;
  	}
  }
  
  static bool should_fill_key(const struct sw_flow_id *sfid, uint32_t ufid_flags)
  {
  	return ovs_identifier_is_ufid(sfid) &&
  	       !(ufid_flags & OVS_UFID_F_OMIT_KEY);
  }
  
  static bool should_fill_mask(uint32_t ufid_flags)
  {
  	return !(ufid_flags & OVS_UFID_F_OMIT_MASK);
  }
  
  static bool should_fill_actions(uint32_t ufid_flags)
  {
  	return !(ufid_flags & OVS_UFID_F_OMIT_ACTIONS);
  }
  
  static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts,
  				    const struct sw_flow_id *sfid,
  				    uint32_t ufid_flags)
  {
  	size_t len = NLMSG_ALIGN(sizeof(struct ovs_header));
  
  	/* OVS_FLOW_ATTR_UFID */
  	if (sfid && ovs_identifier_is_ufid(sfid))
  		len += nla_total_size(sfid->ufid_len);
  
  	/* OVS_FLOW_ATTR_KEY */
  	if (!sfid || should_fill_key(sfid, ufid_flags))
  		len += nla_total_size(ovs_key_attr_size());
  
  	/* OVS_FLOW_ATTR_MASK */
  	if (should_fill_mask(ufid_flags))
  		len += nla_total_size(ovs_key_attr_size());
  
  	/* OVS_FLOW_ATTR_ACTIONS */
  	if (should_fill_actions(ufid_flags))
  		len += nla_total_size(acts->orig_len);
  
  	return len
  		+ nla_total_size_64bit(sizeof(struct ovs_flow_stats)) /* OVS_FLOW_ATTR_STATS */
  		+ nla_total_size(1) /* OVS_FLOW_ATTR_TCP_FLAGS */
  		+ nla_total_size_64bit(8); /* OVS_FLOW_ATTR_USED */
  }
  
  /* Called with ovs_mutex or RCU read lock. */
  static int ovs_flow_cmd_fill_stats(const struct sw_flow *flow,
  				   struct sk_buff *skb)
  {
  	struct ovs_flow_stats stats;
  	__be16 tcp_flags;
  	unsigned long used;
  
  	ovs_flow_stats_get(flow, &stats, &used, &tcp_flags);
  
  	if (used &&
  	    nla_put_u64_64bit(skb, OVS_FLOW_ATTR_USED, ovs_flow_used_time(used),
  			      OVS_FLOW_ATTR_PAD))
  		return -EMSGSIZE;
  
  	if (stats.n_packets &&
  	    nla_put_64bit(skb, OVS_FLOW_ATTR_STATS,
  			  sizeof(struct ovs_flow_stats), &stats,
  			  OVS_FLOW_ATTR_PAD))
  		return -EMSGSIZE;
  
  	if ((u8)ntohs(tcp_flags) &&
  	     nla_put_u8(skb, OVS_FLOW_ATTR_TCP_FLAGS, (u8)ntohs(tcp_flags)))
  		return -EMSGSIZE;
  
  	return 0;
  }
  
  /* Called with ovs_mutex or RCU read lock. */
  static int ovs_flow_cmd_fill_actions(const struct sw_flow *flow,
  				     struct sk_buff *skb, int skb_orig_len)
  {
  	struct nlattr *start;
  	int err;
  
  	/* If OVS_FLOW_ATTR_ACTIONS doesn't fit, skip dumping the actions if
  	 * this is the first flow to be dumped into 'skb'.  This is unusual for
  	 * Netlink but individual action lists can be longer than
  	 * NLMSG_GOODSIZE and thus entirely undumpable if we didn't do this.
  	 * The userspace caller can always fetch the actions separately if it
  	 * really wants them.  (Most userspace callers in fact don't care.)
  	 *
  	 * This can only fail for dump operations because the skb is always
  	 * properly sized for single flows.
  	 */
  	start = nla_nest_start(skb, OVS_FLOW_ATTR_ACTIONS);
  	if (start) {
  		const struct sw_flow_actions *sf_acts;
  
  		sf_acts = rcu_dereference_ovsl(flow->sf_acts);
  		err = ovs_nla_put_actions(sf_acts->actions,
  					  sf_acts->actions_len, skb);
  
  		if (!err)
  			nla_nest_end(skb, start);
  		else {
  			if (skb_orig_len)
  				return err;
  
  			nla_nest_cancel(skb, start);
  		}
  	} else if (skb_orig_len) {
  		return -EMSGSIZE;
  	}
  
  	return 0;
  }
  
  /* Called with ovs_mutex or RCU read lock. */
  static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
  				  struct sk_buff *skb, u32 portid,
  				  u32 seq, u32 flags, u8 cmd, u32 ufid_flags)
  {
  	const int skb_orig_len = skb->len;
  	struct ovs_header *ovs_header;
  	int err;
  
  	ovs_header = genlmsg_put(skb, portid, seq, &dp_flow_genl_family,
  				 flags, cmd);
  	if (!ovs_header)
  		return -EMSGSIZE;
  
  	ovs_header->dp_ifindex = dp_ifindex;
  
  	err = ovs_nla_put_identifier(flow, skb);
  	if (err)
  		goto error;
  
  	if (should_fill_key(&flow->id, ufid_flags)) {
  		err = ovs_nla_put_masked_key(flow, skb);
  		if (err)
  			goto error;
  	}
  
  	if (should_fill_mask(ufid_flags)) {
  		err = ovs_nla_put_mask(flow, skb);
  		if (err)
  			goto error;
  	}
  
  	err = ovs_flow_cmd_fill_stats(flow, skb);
  	if (err)
  		goto error;
  
  	if (should_fill_actions(ufid_flags)) {
  		err = ovs_flow_cmd_fill_actions(flow, skb, skb_orig_len);
  		if (err)
  			goto error;
  	}
  
  	genlmsg_end(skb, ovs_header);
  	return 0;
  
  error:
  	genlmsg_cancel(skb, ovs_header);
  	return err;
  }
  
  /* May not be called with RCU read lock. */
  static struct sk_buff *ovs_flow_cmd_alloc_info(const struct sw_flow_actions *acts,
  					       const struct sw_flow_id *sfid,
  					       struct genl_info *info,
  					       bool always,
  					       uint32_t ufid_flags)
  {
  	struct sk_buff *skb;
  	size_t len;
  
  	if (!always && !ovs_must_notify(&dp_flow_genl_family, info, 0))
  		return NULL;
  
  	len = ovs_flow_cmd_msg_size(acts, sfid, ufid_flags);
  	skb = genlmsg_new(len, GFP_KERNEL);
  	if (!skb)
  		return ERR_PTR(-ENOMEM);
  
  	return skb;
  }
  
  /* Called with ovs_mutex. */
  static struct sk_buff *ovs_flow_cmd_build_info(const struct sw_flow *flow,
  					       int dp_ifindex,
  					       struct genl_info *info, u8 cmd,
  					       bool always, u32 ufid_flags)
  {
  	struct sk_buff *skb;
  	int retval;
  
  	skb = ovs_flow_cmd_alloc_info(ovsl_dereference(flow->sf_acts),
  				      &flow->id, info, always, ufid_flags);
  	if (IS_ERR_OR_NULL(skb))
  		return skb;
  
  	retval = ovs_flow_cmd_fill_info(flow, dp_ifindex, skb,
  					info->snd_portid, info->snd_seq, 0,
  					cmd, ufid_flags);
  	BUG_ON(retval < 0);
  	return skb;
  }
  
  static int ovs_flow_cmd_new(struct sk_buff *skb, struct genl_info *info)
  {
  	struct net *net = sock_net(skb->sk);
  	struct nlattr **a = info->attrs;
  	struct ovs_header *ovs_header = info->userhdr;
  	struct sw_flow *flow = NULL, *new_flow;
  	struct sw_flow_mask mask;
  	struct sk_buff *reply;
  	struct datapath *dp;
  	struct sw_flow_actions *acts;
  	struct sw_flow_match match;
  	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
  	int error;
  	bool log = !a[OVS_FLOW_ATTR_PROBE];
  
  	/* Must have key and actions. */
  	error = -EINVAL;
  	if (!a[OVS_FLOW_ATTR_KEY]) {
  		OVS_NLERR(log, "Flow key attr not present in new flow.");
  		goto error;
  	}
  	if (!a[OVS_FLOW_ATTR_ACTIONS]) {
  		OVS_NLERR(log, "Flow actions attr not present in new flow.");
  		goto error;
  	}
  
  	/* Most of the time we need to allocate a new flow, do it before
  	 * locking.
  	 */
  	new_flow = ovs_flow_alloc();
  	if (IS_ERR(new_flow)) {
  		error = PTR_ERR(new_flow);
  		goto error;
  	}
  
  	/* Extract key. */
  	ovs_match_init(&match, &new_flow->key, false, &mask);
  	error = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
  				  a[OVS_FLOW_ATTR_MASK], log);
  	if (error)
  		goto err_kfree_flow;
  
  	/* Extract flow identifier. */
  	error = ovs_nla_get_identifier(&new_flow->id, a[OVS_FLOW_ATTR_UFID],
  				       &new_flow->key, log);
  	if (error)
  		goto err_kfree_flow;
  
  	/* unmasked key is needed to match when ufid is not used. */
  	if (ovs_identifier_is_key(&new_flow->id))
  		match.key = new_flow->id.unmasked_key;
  
  	ovs_flow_mask_key(&new_flow->key, &new_flow->key, true, &mask);
  
  	/* Validate actions. */
  	error = ovs_nla_copy_actions(net, a[OVS_FLOW_ATTR_ACTIONS],
  				     &new_flow->key, &acts, log);
  	if (error) {
  		OVS_NLERR(log, "Flow actions may not be safe on all matching packets.");
  		goto err_kfree_flow;
  	}
  
  	reply = ovs_flow_cmd_alloc_info(acts, &new_flow->id, info, false,
  					ufid_flags);
  	if (IS_ERR(reply)) {
  		error = PTR_ERR(reply);
  		goto err_kfree_acts;
  	}
  
  	ovs_lock();
  	dp = get_dp(net, ovs_header->dp_ifindex);
  	if (unlikely(!dp)) {
  		error = -ENODEV;
  		goto err_unlock_ovs;
  	}
  
  	/* Check if this is a duplicate flow */
  	if (ovs_identifier_is_ufid(&new_flow->id))
  		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &new_flow->id);
  	if (!flow)
  		flow = ovs_flow_tbl_lookup(&dp->table, &new_flow->key);
  	if (likely(!flow)) {
  		rcu_assign_pointer(new_flow->sf_acts, acts);
  
  		/* Put flow in bucket. */
  		error = ovs_flow_tbl_insert(&dp->table, new_flow, &mask);
  		if (unlikely(error)) {
  			acts = NULL;
  			goto err_unlock_ovs;
  		}
  
  		if (unlikely(reply)) {
  			error = ovs_flow_cmd_fill_info(new_flow,
  						       ovs_header->dp_ifindex,
  						       reply, info->snd_portid,
  						       info->snd_seq, 0,
  						       OVS_FLOW_CMD_NEW,
  						       ufid_flags);
  			BUG_ON(error < 0);
  		}
  		ovs_unlock();
  	} else {
  		struct sw_flow_actions *old_acts;
  
  		/* Bail out if we're not allowed to modify an existing flow.
  		 * We accept NLM_F_CREATE in place of the intended NLM_F_EXCL
  		 * because Generic Netlink treats the latter as a dump
  		 * request.  We also accept NLM_F_EXCL in case that bug ever
  		 * gets fixed.
  		 */
  		if (unlikely(info->nlhdr->nlmsg_flags & (NLM_F_CREATE
  							 | NLM_F_EXCL))) {
  			error = -EEXIST;
  			goto err_unlock_ovs;
  		}
  		/* The flow identifier has to be the same for flow updates.
  		 * Look for any overlapping flow.
  		 */
  		if (unlikely(!ovs_flow_cmp(flow, &match))) {
  			if (ovs_identifier_is_key(&flow->id))
  				flow = ovs_flow_tbl_lookup_exact(&dp->table,
  								 &match);
  			else /* UFID matches but key is different */
  				flow = NULL;
  			if (!flow) {
  				error = -ENOENT;
  				goto err_unlock_ovs;
  			}
  		}
  		/* Update actions. */
  		old_acts = ovsl_dereference(flow->sf_acts);
  		rcu_assign_pointer(flow->sf_acts, acts);
  
  		if (unlikely(reply)) {
  			error = ovs_flow_cmd_fill_info(flow,
  						       ovs_header->dp_ifindex,
  						       reply, info->snd_portid,
  						       info->snd_seq, 0,
  						       OVS_FLOW_CMD_NEW,
  						       ufid_flags);
  			BUG_ON(error < 0);
  		}
  		ovs_unlock();
  
  		ovs_nla_free_flow_actions_rcu(old_acts);
  		ovs_flow_free(new_flow, false);
  	}
  
  	if (reply)
  		ovs_notify(&dp_flow_genl_family, reply, info);
  	return 0;
  
  err_unlock_ovs:
  	ovs_unlock();
  	kfree_skb(reply);
  err_kfree_acts:
  	ovs_nla_free_flow_actions(acts);
  err_kfree_flow:
  	ovs_flow_free(new_flow, false);
  error:
  	return error;
  }
  
  /* Factor out action copy to avoid "Wframe-larger-than=1024" warning. */
  static struct sw_flow_actions *get_flow_actions(struct net *net,
  						const struct nlattr *a,
  						const struct sw_flow_key *key,
  						const struct sw_flow_mask *mask,
  						bool log)
  {
  	struct sw_flow_actions *acts;
  	struct sw_flow_key masked_key;
  	int error;
  
  	ovs_flow_mask_key(&masked_key, key, true, mask);
  	error = ovs_nla_copy_actions(net, a, &masked_key, &acts, log);
  	if (error) {
  		OVS_NLERR(log,
  			  "Actions may not be safe on all matching packets");
  		return ERR_PTR(error);
  	}
  
  	return acts;
  }
  
  /* Factor out match-init and action-copy to avoid
   * "Wframe-larger-than=1024" warning. Because mask is only
   * used to get actions, we new a function to save some
   * stack space.
   *
   * If there are not key and action attrs, we return 0
   * directly. In the case, the caller will also not use the
   * match as before. If there is action attr, we try to get
   * actions and save them to *acts. Before returning from
   * the function, we reset the match->mask pointer. Because
   * we should not to return match object with dangling reference
   * to mask.
   * */
  static int ovs_nla_init_match_and_action(struct net *net,
  					 struct sw_flow_match *match,
  					 struct sw_flow_key *key,
  					 struct nlattr **a,
  					 struct sw_flow_actions **acts,
  					 bool log)
  {
  	struct sw_flow_mask mask;
  	int error = 0;
  
  	if (a[OVS_FLOW_ATTR_KEY]) {
  		ovs_match_init(match, key, true, &mask);
  		error = ovs_nla_get_match(net, match, a[OVS_FLOW_ATTR_KEY],
  					  a[OVS_FLOW_ATTR_MASK], log);
  		if (error)
  			goto error;
  	}
  
  	if (a[OVS_FLOW_ATTR_ACTIONS]) {
  		if (!a[OVS_FLOW_ATTR_KEY]) {
  			OVS_NLERR(log,
  				  "Flow key attribute not present in set flow.");
  			error = -EINVAL;
  			goto error;
  		}
  
  		*acts = get_flow_actions(net, a[OVS_FLOW_ATTR_ACTIONS], key,
  					 &mask, log);
  		if (IS_ERR(*acts)) {
  			error = PTR_ERR(*acts);
  			goto error;
  		}
  	}
  
  	/* On success, error is 0. */
  error:
  	match->mask = NULL;
  	return error;
  }
  
  static int ovs_flow_cmd_set(struct sk_buff *skb, struct genl_info *info)
  {
  	struct net *net = sock_net(skb->sk);
  	struct nlattr **a = info->attrs;
  	struct ovs_header *ovs_header = info->userhdr;
  	struct sw_flow_key key;
  	struct sw_flow *flow;
  	struct sk_buff *reply = NULL;
  	struct datapath *dp;
  	struct sw_flow_actions *old_acts = NULL, *acts = NULL;
  	struct sw_flow_match match;
  	struct sw_flow_id sfid;
  	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
  	int error = 0;
  	bool log = !a[OVS_FLOW_ATTR_PROBE];
  	bool ufid_present;
  
  	ufid_present = ovs_nla_get_ufid(&sfid, a[OVS_FLOW_ATTR_UFID], log);
  	if (!a[OVS_FLOW_ATTR_KEY] && !ufid_present) {
  		OVS_NLERR(log,
  			  "Flow set message rejected, Key attribute missing.");
  		return -EINVAL;
  	}
  
  	error = ovs_nla_init_match_and_action(net, &match, &key, a,
  					      &acts, log);
  	if (error)
  		goto error;
  
  	if (acts) {
  		/* Can allocate before locking if have acts. */
  		reply = ovs_flow_cmd_alloc_info(acts, &sfid, info, false,
  						ufid_flags);
  		if (IS_ERR(reply)) {
  			error = PTR_ERR(reply);
  			goto err_kfree_acts;
  		}
  	}
  
  	ovs_lock();
  	dp = get_dp(net, ovs_header->dp_ifindex);
  	if (unlikely(!dp)) {
  		error = -ENODEV;
  		goto err_unlock_ovs;
  	}
  	/* Check that the flow exists. */
  	if (ufid_present)
  		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &sfid);
  	else
  		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
  	if (unlikely(!flow)) {
  		error = -ENOENT;
  		goto err_unlock_ovs;
  	}
  
  	/* Update actions, if present. */
  	if (likely(acts)) {
  		old_acts = ovsl_dereference(flow->sf_acts);
  		rcu_assign_pointer(flow->sf_acts, acts);
  
  		if (unlikely(reply)) {
  			error = ovs_flow_cmd_fill_info(flow,
  						       ovs_header->dp_ifindex,
  						       reply, info->snd_portid,
  						       info->snd_seq, 0,
  						       OVS_FLOW_CMD_SET,
  						       ufid_flags);
  			BUG_ON(error < 0);
  		}
  	} else {
  		/* Could not alloc without acts before locking. */
  		reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex,
  						info, OVS_FLOW_CMD_SET, false,
  						ufid_flags);
  
  		if (IS_ERR(reply)) {
  			error = PTR_ERR(reply);
  			goto err_unlock_ovs;
  		}
  	}
  
  	/* Clear stats. */
  	if (a[OVS_FLOW_ATTR_CLEAR])
  		ovs_flow_stats_clear(flow);
  	ovs_unlock();
  
  	if (reply)
  		ovs_notify(&dp_flow_genl_family, reply, info);
  	if (old_acts)
  		ovs_nla_free_flow_actions_rcu(old_acts);
  
  	return 0;
  
  err_unlock_ovs:
  	ovs_unlock();
  	kfree_skb(reply);
  err_kfree_acts:
  	ovs_nla_free_flow_actions(acts);
  error:
  	return error;
  }
  
  static int ovs_flow_cmd_get(struct sk_buff *skb, struct genl_info *info)
  {
  	struct nlattr **a = info->attrs;
  	struct ovs_header *ovs_header = info->userhdr;
  	struct net *net = sock_net(skb->sk);
  	struct sw_flow_key key;
  	struct sk_buff *reply;
  	struct sw_flow *flow;
  	struct datapath *dp;
  	struct sw_flow_match match;
  	struct sw_flow_id ufid;
  	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
  	int err = 0;
  	bool log = !a[OVS_FLOW_ATTR_PROBE];
  	bool ufid_present;
  
  	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
  	if (a[OVS_FLOW_ATTR_KEY]) {
  		ovs_match_init(&match, &key, true, NULL);
  		err = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY], NULL,
  					log);
  	} else if (!ufid_present) {
  		OVS_NLERR(log,
  			  "Flow get message rejected, Key attribute missing.");
  		err = -EINVAL;
  	}
  	if (err)
  		return err;
  
  	ovs_lock();
  	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
  	if (!dp) {
  		err = -ENODEV;
  		goto unlock;
  	}
  
  	if (ufid_present)
  		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
  	else
  		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
  	if (!flow) {
  		err = -ENOENT;
  		goto unlock;
  	}
  
  	reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex, info,
  					OVS_FLOW_CMD_GET, true, ufid_flags);
  	if (IS_ERR(reply)) {
  		err = PTR_ERR(reply);
  		goto unlock;
  	}
  
  	ovs_unlock();
  	return genlmsg_reply(reply, info);
  unlock:
  	ovs_unlock();
  	return err;
  }
  
  static int ovs_flow_cmd_del(struct sk_buff *skb, struct genl_info *info)
  {
  	struct nlattr **a = info->attrs;
  	struct ovs_header *ovs_header = info->userhdr;
  	struct net *net = sock_net(skb->sk);
  	struct sw_flow_key key;
  	struct sk_buff *reply;
  	struct sw_flow *flow = NULL;
  	struct datapath *dp;
  	struct sw_flow_match match;
  	struct sw_flow_id ufid;
  	u32 ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
  	int err;
  	bool log = !a[OVS_FLOW_ATTR_PROBE];
  	bool ufid_present;
  
  	ufid_present = ovs_nla_get_ufid(&ufid, a[OVS_FLOW_ATTR_UFID], log);
  	if (a[OVS_FLOW_ATTR_KEY]) {
  		ovs_match_init(&match, &key, true, NULL);
  		err = ovs_nla_get_match(net, &match, a[OVS_FLOW_ATTR_KEY],
  					NULL, log);
  		if (unlikely(err))
  			return err;
  	}
  
  	ovs_lock();
  	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
  	if (unlikely(!dp)) {
  		err = -ENODEV;
  		goto unlock;
  	}
  
  	if (unlikely(!a[OVS_FLOW_ATTR_KEY] && !ufid_present)) {
  		err = ovs_flow_tbl_flush(&dp->table);
  		goto unlock;
  	}
  
  	if (ufid_present)
  		flow = ovs_flow_tbl_lookup_ufid(&dp->table, &ufid);
  	else
  		flow = ovs_flow_tbl_lookup_exact(&dp->table, &match);
  	if (unlikely(!flow)) {
  		err = -ENOENT;
  		goto unlock;
  	}
  
  	ovs_flow_tbl_remove(&dp->table, flow);
  	ovs_unlock();
  
  	reply = ovs_flow_cmd_alloc_info((const struct sw_flow_actions __force *) flow->sf_acts,
  					&flow->id, info, false, ufid_flags);
  	if (likely(reply)) {
  		if (likely(!IS_ERR(reply))) {
  			rcu_read_lock();	/*To keep RCU checker happy. */
  			err = ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex,
  						     reply, info->snd_portid,
  						     info->snd_seq, 0,
  						     OVS_FLOW_CMD_DEL,
  						     ufid_flags);
  			rcu_read_unlock();
  			BUG_ON(err < 0);
  
  			ovs_notify(&dp_flow_genl_family, reply, info);
  		} else {
  			netlink_set_err(sock_net(skb->sk)->genl_sock, 0, 0, PTR_ERR(reply));
  		}
  	}
  
  	ovs_flow_free(flow, true);
  	return 0;
  unlock:
  	ovs_unlock();
  	return err;
  }
  
  static int ovs_flow_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
  {
  	struct nlattr *a[__OVS_FLOW_ATTR_MAX];
  	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
  	struct table_instance *ti;
  	struct datapath *dp;
  	u32 ufid_flags;
  	int err;
  
  	err = genlmsg_parse(cb->nlh, &dp_flow_genl_family, a,
  			    OVS_FLOW_ATTR_MAX, flow_policy, NULL);
  	if (err)
  		return err;
  	ufid_flags = ovs_nla_get_ufid_flags(a[OVS_FLOW_ATTR_UFID_FLAGS]);
  
  	rcu_read_lock();
  	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
  	if (!dp) {
  		rcu_read_unlock();
  		return -ENODEV;
  	}
  
  	ti = rcu_dereference(dp->table.ti);
  	for (;;) {
  		struct sw_flow *flow;
  		u32 bucket, obj;
  
  		bucket = cb->args[0];
  		obj = cb->args[1];
  		flow = ovs_flow_tbl_dump_next(ti, &bucket, &obj);
  		if (!flow)
  			break;
  
  		if (ovs_flow_cmd_fill_info(flow, ovs_header->dp_ifindex, skb,
  					   NETLINK_CB(cb->skb).portid,
  					   cb->nlh->nlmsg_seq, NLM_F_MULTI,
  					   OVS_FLOW_CMD_GET, ufid_flags) < 0)
  			break;
  
  		cb->args[0] = bucket;
  		cb->args[1] = obj;
  	}
  	rcu_read_unlock();
  	return skb->len;
  }
  
  static const struct nla_policy flow_policy[OVS_FLOW_ATTR_MAX + 1] = {
  	[OVS_FLOW_ATTR_KEY] = { .type = NLA_NESTED },
  	[OVS_FLOW_ATTR_MASK] = { .type = NLA_NESTED },
  	[OVS_FLOW_ATTR_ACTIONS] = { .type = NLA_NESTED },
  	[OVS_FLOW_ATTR_CLEAR] = { .type = NLA_FLAG },
  	[OVS_FLOW_ATTR_PROBE] = { .type = NLA_FLAG },
  	[OVS_FLOW_ATTR_UFID] = { .type = NLA_UNSPEC, .len = 1 },
  	[OVS_FLOW_ATTR_UFID_FLAGS] = { .type = NLA_U32 },
  };
  
  static const struct genl_ops dp_flow_genl_ops[] = {
  	{ .cmd = OVS_FLOW_CMD_NEW,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = flow_policy,
  	  .doit = ovs_flow_cmd_new
  	},
  	{ .cmd = OVS_FLOW_CMD_DEL,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = flow_policy,
  	  .doit = ovs_flow_cmd_del
  	},
  	{ .cmd = OVS_FLOW_CMD_GET,
  	  .flags = 0,		    /* OK for unprivileged users. */
  	  .policy = flow_policy,
  	  .doit = ovs_flow_cmd_get,
  	  .dumpit = ovs_flow_cmd_dump
  	},
  	{ .cmd = OVS_FLOW_CMD_SET,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = flow_policy,
  	  .doit = ovs_flow_cmd_set,
  	},
  };
  
  static struct genl_family dp_flow_genl_family __ro_after_init = {
  	.hdrsize = sizeof(struct ovs_header),
  	.name = OVS_FLOW_FAMILY,
  	.version = OVS_FLOW_VERSION,
  	.maxattr = OVS_FLOW_ATTR_MAX,
  	.netnsok = true,
  	.parallel_ops = true,
  	.ops = dp_flow_genl_ops,
  	.n_ops = ARRAY_SIZE(dp_flow_genl_ops),
  	.mcgrps = &ovs_dp_flow_multicast_group,
  	.n_mcgrps = 1,
  	.module = THIS_MODULE,
  };
  
  static size_t ovs_dp_cmd_msg_size(void)
  {
  	size_t msgsize = NLMSG_ALIGN(sizeof(struct ovs_header));
  
  	msgsize += nla_total_size(IFNAMSIZ);
  	msgsize += nla_total_size_64bit(sizeof(struct ovs_dp_stats));
  	msgsize += nla_total_size_64bit(sizeof(struct ovs_dp_megaflow_stats));
  	msgsize += nla_total_size(sizeof(u32)); /* OVS_DP_ATTR_USER_FEATURES */
  
  	return msgsize;
  }
  
  /* Called with ovs_mutex. */
  static int ovs_dp_cmd_fill_info(struct datapath *dp, struct sk_buff *skb,
  				u32 portid, u32 seq, u32 flags, u8 cmd)
  {
  	struct ovs_header *ovs_header;
  	struct ovs_dp_stats dp_stats;
  	struct ovs_dp_megaflow_stats dp_megaflow_stats;
  	int err;
  
  	ovs_header = genlmsg_put(skb, portid, seq, &dp_datapath_genl_family,
  				   flags, cmd);
  	if (!ovs_header)
  		goto error;
  
  	ovs_header->dp_ifindex = get_dpifindex(dp);
  
  	err = nla_put_string(skb, OVS_DP_ATTR_NAME, ovs_dp_name(dp));
  	if (err)
  		goto nla_put_failure;
  
  	get_dp_stats(dp, &dp_stats, &dp_megaflow_stats);
  	if (nla_put_64bit(skb, OVS_DP_ATTR_STATS, sizeof(struct ovs_dp_stats),
  			  &dp_stats, OVS_DP_ATTR_PAD))
  		goto nla_put_failure;
  
  	if (nla_put_64bit(skb, OVS_DP_ATTR_MEGAFLOW_STATS,
  			  sizeof(struct ovs_dp_megaflow_stats),
  			  &dp_megaflow_stats, OVS_DP_ATTR_PAD))
  		goto nla_put_failure;
  
  	if (nla_put_u32(skb, OVS_DP_ATTR_USER_FEATURES, dp->user_features))
  		goto nla_put_failure;
  
  	genlmsg_end(skb, ovs_header);
  	return 0;
  
  nla_put_failure:
  	genlmsg_cancel(skb, ovs_header);
  error:
  	return -EMSGSIZE;
  }
  
  static struct sk_buff *ovs_dp_cmd_alloc_info(void)
  {
  	return genlmsg_new(ovs_dp_cmd_msg_size(), GFP_KERNEL);
  }
  
  /* Called with rcu_read_lock or ovs_mutex. */
  static struct datapath *lookup_datapath(struct net *net,
  					const struct ovs_header *ovs_header,
  					struct nlattr *a[OVS_DP_ATTR_MAX + 1])
  {
  	struct datapath *dp;
  
  	if (!a[OVS_DP_ATTR_NAME])
  		dp = get_dp(net, ovs_header->dp_ifindex);
  	else {
  		struct vport *vport;
  
  		vport = ovs_vport_locate(net, nla_data(a[OVS_DP_ATTR_NAME]));
  		dp = vport && vport->port_no == OVSP_LOCAL ? vport->dp : NULL;
  	}
  	return dp ? dp : ERR_PTR(-ENODEV);
  }
  
  static void ovs_dp_reset_user_features(struct sk_buff *skb, struct genl_info *info)
  {
  	struct datapath *dp;
  
  	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
  	if (IS_ERR(dp))
  		return;
  
  	WARN(dp->user_features, "Dropping previously announced user features\n");
  	dp->user_features = 0;
  }
  
  static void ovs_dp_change(struct datapath *dp, struct nlattr *a[])
  {
  	if (a[OVS_DP_ATTR_USER_FEATURES])
  		dp->user_features = nla_get_u32(a[OVS_DP_ATTR_USER_FEATURES]);
  }
  
  static int ovs_dp_cmd_new(struct sk_buff *skb, struct genl_info *info)
  {
  	struct nlattr **a = info->attrs;
  	struct vport_parms parms;
  	struct sk_buff *reply;
  	struct datapath *dp;
  	struct vport *vport;
  	struct ovs_net *ovs_net;
  	int err, i;
  
  	err = -EINVAL;
  	if (!a[OVS_DP_ATTR_NAME] || !a[OVS_DP_ATTR_UPCALL_PID])
  		goto err;
  
  	reply = ovs_dp_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	err = -ENOMEM;
  	dp = kzalloc(sizeof(*dp), GFP_KERNEL);
  	if (dp == NULL)
  		goto err_free_reply;
  
  	ovs_dp_set_net(dp, sock_net(skb->sk));
  
  	/* Allocate table. */
  	err = ovs_flow_tbl_init(&dp->table);
  	if (err)
  		goto err_free_dp;
  
  	dp->stats_percpu = netdev_alloc_pcpu_stats(struct dp_stats_percpu);
  	if (!dp->stats_percpu) {
  		err = -ENOMEM;
  		goto err_destroy_table;
  	}
  
  	dp->ports = kmalloc_array(DP_VPORT_HASH_BUCKETS,
  				  sizeof(struct hlist_head),
  				  GFP_KERNEL);
  	if (!dp->ports) {
  		err = -ENOMEM;
  		goto err_destroy_percpu;
  	}
  
  	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
  		INIT_HLIST_HEAD(&dp->ports[i]);
  
  	err = ovs_meters_init(dp);
  	if (err)
  		goto err_destroy_ports_array;
  
  	/* Set up our datapath device. */
  	parms.name = nla_data(a[OVS_DP_ATTR_NAME]);
  	parms.type = OVS_VPORT_TYPE_INTERNAL;
  	parms.options = NULL;
  	parms.dp = dp;
  	parms.port_no = OVSP_LOCAL;
  	parms.upcall_portids = a[OVS_DP_ATTR_UPCALL_PID];
  
  	ovs_dp_change(dp, a);
  
  	/* So far only local changes have been made, now need the lock. */
  	ovs_lock();
  
  	vport = new_vport(&parms);
  	if (IS_ERR(vport)) {
  		err = PTR_ERR(vport);
  		if (err == -EBUSY)
  			err = -EEXIST;
  
  		if (err == -EEXIST) {
  			/* An outdated user space instance that does not understand
  			 * the concept of user_features has attempted to create a new
  			 * datapath and is likely to reuse it. Drop all user features.
  			 */
  			if (info->genlhdr->version < OVS_DP_VER_FEATURES)
  				ovs_dp_reset_user_features(skb, info);
  		}
  
  		goto err_destroy_meters;
  	}
  
  	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
  				   info->snd_seq, 0, OVS_DP_CMD_NEW);
  	BUG_ON(err < 0);
  
  	ovs_net = net_generic(ovs_dp_get_net(dp), ovs_net_id);
  	list_add_tail_rcu(&dp->list_node, &ovs_net->dps);
  
  	ovs_unlock();
  
  	ovs_notify(&dp_datapath_genl_family, reply, info);
  	return 0;
  
  err_destroy_meters:
  	ovs_unlock();
  	ovs_meters_exit(dp);
  err_destroy_ports_array:
  	kfree(dp->ports);
  err_destroy_percpu:
  	free_percpu(dp->stats_percpu);
  err_destroy_table:
  	ovs_flow_tbl_destroy(&dp->table);
  err_free_dp:
  	kfree(dp);
  err_free_reply:
  	kfree_skb(reply);
  err:
  	return err;
  }
  
  /* Called with ovs_mutex. */
  static void __dp_destroy(struct datapath *dp)
  {
  	int i;
  
  	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
  		struct vport *vport;
  		struct hlist_node *n;
  
  		hlist_for_each_entry_safe(vport, n, &dp->ports[i], dp_hash_node)
  			if (vport->port_no != OVSP_LOCAL)
  				ovs_dp_detach_port(vport);
  	}
  
  	list_del_rcu(&dp->list_node);
  
  	/* OVSP_LOCAL is datapath internal port. We need to make sure that
  	 * all ports in datapath are destroyed first before freeing datapath.
  	 */
  	ovs_dp_detach_port(ovs_vport_ovsl(dp, OVSP_LOCAL));
  
  	/* RCU destroy the flow table */
  	call_rcu(&dp->rcu, destroy_dp_rcu);
  }
  
  static int ovs_dp_cmd_del(struct sk_buff *skb, struct genl_info *info)
  {
  	struct sk_buff *reply;
  	struct datapath *dp;
  	int err;
  
  	reply = ovs_dp_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	ovs_lock();
  	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
  	err = PTR_ERR(dp);
  	if (IS_ERR(dp))
  		goto err_unlock_free;
  
  	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
  				   info->snd_seq, 0, OVS_DP_CMD_DEL);
  	BUG_ON(err < 0);
  
  	__dp_destroy(dp);
  	ovs_unlock();
  
  	ovs_notify(&dp_datapath_genl_family, reply, info);
  
  	return 0;
  
  err_unlock_free:
  	ovs_unlock();
  	kfree_skb(reply);
  	return err;
  }
  
  static int ovs_dp_cmd_set(struct sk_buff *skb, struct genl_info *info)
  {
  	struct sk_buff *reply;
  	struct datapath *dp;
  	int err;
  
  	reply = ovs_dp_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	ovs_lock();
  	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
  	err = PTR_ERR(dp);
  	if (IS_ERR(dp))
  		goto err_unlock_free;
  
  	ovs_dp_change(dp, info->attrs);
  
  	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
  				   info->snd_seq, 0, OVS_DP_CMD_SET);
  	BUG_ON(err < 0);
  
  	ovs_unlock();
  	ovs_notify(&dp_datapath_genl_family, reply, info);
  
  	return 0;
  
  err_unlock_free:
  	ovs_unlock();
  	kfree_skb(reply);
  	return err;
  }
  
  static int ovs_dp_cmd_get(struct sk_buff *skb, struct genl_info *info)
  {
  	struct sk_buff *reply;
  	struct datapath *dp;
  	int err;
  
  	reply = ovs_dp_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	ovs_lock();
  	dp = lookup_datapath(sock_net(skb->sk), info->userhdr, info->attrs);
  	if (IS_ERR(dp)) {
  		err = PTR_ERR(dp);
  		goto err_unlock_free;
  	}
  	err = ovs_dp_cmd_fill_info(dp, reply, info->snd_portid,
  				   info->snd_seq, 0, OVS_DP_CMD_GET);
  	BUG_ON(err < 0);
  	ovs_unlock();
  
  	return genlmsg_reply(reply, info);
  
  err_unlock_free:
  	ovs_unlock();
  	kfree_skb(reply);
  	return err;
  }
  
  static int ovs_dp_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
  {
  	struct ovs_net *ovs_net = net_generic(sock_net(skb->sk), ovs_net_id);
  	struct datapath *dp;
  	int skip = cb->args[0];
  	int i = 0;
  
  	ovs_lock();
  	list_for_each_entry(dp, &ovs_net->dps, list_node) {
  		if (i >= skip &&
  		    ovs_dp_cmd_fill_info(dp, skb, NETLINK_CB(cb->skb).portid,
  					 cb->nlh->nlmsg_seq, NLM_F_MULTI,
  					 OVS_DP_CMD_GET) < 0)
  			break;
  		i++;
  	}
  	ovs_unlock();
  
  	cb->args[0] = i;
  
  	return skb->len;
  }
  
  static const struct nla_policy datapath_policy[OVS_DP_ATTR_MAX + 1] = {
  	[OVS_DP_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
  	[OVS_DP_ATTR_UPCALL_PID] = { .type = NLA_U32 },
  	[OVS_DP_ATTR_USER_FEATURES] = { .type = NLA_U32 },
  };
  
  static const struct genl_ops dp_datapath_genl_ops[] = {
  	{ .cmd = OVS_DP_CMD_NEW,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = datapath_policy,
  	  .doit = ovs_dp_cmd_new
  	},
  	{ .cmd = OVS_DP_CMD_DEL,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = datapath_policy,
  	  .doit = ovs_dp_cmd_del
  	},
  	{ .cmd = OVS_DP_CMD_GET,
  	  .flags = 0,		    /* OK for unprivileged users. */
  	  .policy = datapath_policy,
  	  .doit = ovs_dp_cmd_get,
  	  .dumpit = ovs_dp_cmd_dump
  	},
  	{ .cmd = OVS_DP_CMD_SET,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = datapath_policy,
  	  .doit = ovs_dp_cmd_set,
  	},
  };
  
  static struct genl_family dp_datapath_genl_family __ro_after_init = {
  	.hdrsize = sizeof(struct ovs_header),
  	.name = OVS_DATAPATH_FAMILY,
  	.version = OVS_DATAPATH_VERSION,
  	.maxattr = OVS_DP_ATTR_MAX,
  	.netnsok = true,
  	.parallel_ops = true,
  	.ops = dp_datapath_genl_ops,
  	.n_ops = ARRAY_SIZE(dp_datapath_genl_ops),
  	.mcgrps = &ovs_dp_datapath_multicast_group,
  	.n_mcgrps = 1,
  	.module = THIS_MODULE,
  };
  
  /* Called with ovs_mutex or RCU read lock. */
  static int ovs_vport_cmd_fill_info(struct vport *vport, struct sk_buff *skb,
  				   struct net *net, u32 portid, u32 seq,
  				   u32 flags, u8 cmd)
  {
  	struct ovs_header *ovs_header;
  	struct ovs_vport_stats vport_stats;
  	int err;
  
  	ovs_header = genlmsg_put(skb, portid, seq, &dp_vport_genl_family,
  				 flags, cmd);
  	if (!ovs_header)
  		return -EMSGSIZE;
  
  	ovs_header->dp_ifindex = get_dpifindex(vport->dp);
  
  	if (nla_put_u32(skb, OVS_VPORT_ATTR_PORT_NO, vport->port_no) ||
  	    nla_put_u32(skb, OVS_VPORT_ATTR_TYPE, vport->ops->type) ||
  	    nla_put_string(skb, OVS_VPORT_ATTR_NAME,
  			   ovs_vport_name(vport)) ||
  	    nla_put_u32(skb, OVS_VPORT_ATTR_IFINDEX, vport->dev->ifindex))
  		goto nla_put_failure;
  
  	if (!net_eq(net, dev_net(vport->dev))) {
  		int id = peernet2id_alloc(net, dev_net(vport->dev));
  
  		if (nla_put_s32(skb, OVS_VPORT_ATTR_NETNSID, id))
  			goto nla_put_failure;
  	}
  
  	ovs_vport_get_stats(vport, &vport_stats);
  	if (nla_put_64bit(skb, OVS_VPORT_ATTR_STATS,
  			  sizeof(struct ovs_vport_stats), &vport_stats,
  			  OVS_VPORT_ATTR_PAD))
  		goto nla_put_failure;
  
  	if (ovs_vport_get_upcall_portids(vport, skb))
  		goto nla_put_failure;
  
  	err = ovs_vport_get_options(vport, skb);
  	if (err == -EMSGSIZE)
  		goto error;
  
  	genlmsg_end(skb, ovs_header);
  	return 0;
  
  nla_put_failure:
  	err = -EMSGSIZE;
  error:
  	genlmsg_cancel(skb, ovs_header);
  	return err;
  }
  
  static struct sk_buff *ovs_vport_cmd_alloc_info(void)
  {
  	return nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
  }
  
  /* Called with ovs_mutex, only via ovs_dp_notify_wq(). */
  struct sk_buff *ovs_vport_cmd_build_info(struct vport *vport, struct net *net,
  					 u32 portid, u32 seq, u8 cmd)
  {
  	struct sk_buff *skb;
  	int retval;
  
  	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
  	if (!skb)
  		return ERR_PTR(-ENOMEM);
  
  	retval = ovs_vport_cmd_fill_info(vport, skb, net, portid, seq, 0, cmd);
  	BUG_ON(retval < 0);
  
  	return skb;
  }
  
  /* Called with ovs_mutex or RCU read lock. */
  static struct vport *lookup_vport(struct net *net,
  				  const struct ovs_header *ovs_header,
  				  struct nlattr *a[OVS_VPORT_ATTR_MAX + 1])
  {
  	struct datapath *dp;
  	struct vport *vport;
  
  	if (a[OVS_VPORT_ATTR_IFINDEX])
  		return ERR_PTR(-EOPNOTSUPP);
  	if (a[OVS_VPORT_ATTR_NAME]) {
  		vport = ovs_vport_locate(net, nla_data(a[OVS_VPORT_ATTR_NAME]));
  		if (!vport)
  			return ERR_PTR(-ENODEV);
  		if (ovs_header->dp_ifindex &&
  		    ovs_header->dp_ifindex != get_dpifindex(vport->dp))
  			return ERR_PTR(-ENODEV);
  		return vport;
  	} else if (a[OVS_VPORT_ATTR_PORT_NO]) {
  		u32 port_no = nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]);
  
  		if (port_no >= DP_MAX_PORTS)
  			return ERR_PTR(-EFBIG);
  
  		dp = get_dp(net, ovs_header->dp_ifindex);
  		if (!dp)
  			return ERR_PTR(-ENODEV);
  
  		vport = ovs_vport_ovsl_rcu(dp, port_no);
  		if (!vport)
  			return ERR_PTR(-ENODEV);
  		return vport;
  	} else
  		return ERR_PTR(-EINVAL);
  
  }
  
  /* Called with ovs_mutex */
  static void update_headroom(struct datapath *dp)
  {
  	unsigned dev_headroom, max_headroom = 0;
  	struct net_device *dev;
  	struct vport *vport;
  	int i;
  
  	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
  		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
  			dev = vport->dev;
  			dev_headroom = netdev_get_fwd_headroom(dev);
  			if (dev_headroom > max_headroom)
  				max_headroom = dev_headroom;
  		}
  	}
  
  	dp->max_headroom = max_headroom;
  	for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++)
  		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node)
  			netdev_set_rx_headroom(vport->dev, max_headroom);
  }
  
  static int ovs_vport_cmd_new(struct sk_buff *skb, struct genl_info *info)
  {
  	struct nlattr **a = info->attrs;
  	struct ovs_header *ovs_header = info->userhdr;
  	struct vport_parms parms;
  	struct sk_buff *reply;
  	struct vport *vport;
  	struct datapath *dp;
  	u32 port_no;
  	int err;
  
  	if (!a[OVS_VPORT_ATTR_NAME] || !a[OVS_VPORT_ATTR_TYPE] ||
  	    !a[OVS_VPORT_ATTR_UPCALL_PID])
  		return -EINVAL;
  	if (a[OVS_VPORT_ATTR_IFINDEX])
  		return -EOPNOTSUPP;
  
  	port_no = a[OVS_VPORT_ATTR_PORT_NO]
  		? nla_get_u32(a[OVS_VPORT_ATTR_PORT_NO]) : 0;
  	if (port_no >= DP_MAX_PORTS)
  		return -EFBIG;
  
  	reply = ovs_vport_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	ovs_lock();
  restart:
  	dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
  	err = -ENODEV;
  	if (!dp)
  		goto exit_unlock_free;
  
  	if (port_no) {
  		vport = ovs_vport_ovsl(dp, port_no);
  		err = -EBUSY;
  		if (vport)
  			goto exit_unlock_free;
  	} else {
  		for (port_no = 1; ; port_no++) {
  			if (port_no >= DP_MAX_PORTS) {
  				err = -EFBIG;
  				goto exit_unlock_free;
  			}
  			vport = ovs_vport_ovsl(dp, port_no);
  			if (!vport)
  				break;
  		}
  	}
  
  	parms.name = nla_data(a[OVS_VPORT_ATTR_NAME]);
  	parms.type = nla_get_u32(a[OVS_VPORT_ATTR_TYPE]);
  	parms.options = a[OVS_VPORT_ATTR_OPTIONS];
  	parms.dp = dp;
  	parms.port_no = port_no;
  	parms.upcall_portids = a[OVS_VPORT_ATTR_UPCALL_PID];
  
  	vport = new_vport(&parms);
  	err = PTR_ERR(vport);
  	if (IS_ERR(vport)) {
  		if (err == -EAGAIN)
  			goto restart;
  		goto exit_unlock_free;
  	}
  
  	err = ovs_vport_cmd_fill_info(vport, reply, genl_info_net(info),
  				      info->snd_portid, info->snd_seq, 0,
  				      OVS_VPORT_CMD_NEW);
  
  	if (netdev_get_fwd_headroom(vport->dev) > dp->max_headroom)
  		update_headroom(dp);
  	else
  		netdev_set_rx_headroom(vport->dev, dp->max_headroom);
  
  	BUG_ON(err < 0);
  	ovs_unlock();
  
  	ovs_notify(&dp_vport_genl_family, reply, info);
  	return 0;
  
  exit_unlock_free:
  	ovs_unlock();
  	kfree_skb(reply);
  	return err;
  }
  
  static int ovs_vport_cmd_set(struct sk_buff *skb, struct genl_info *info)
  {
  	struct nlattr **a = info->attrs;
  	struct sk_buff *reply;
  	struct vport *vport;
  	int err;
  
  	reply = ovs_vport_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	ovs_lock();
  	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
  	err = PTR_ERR(vport);
  	if (IS_ERR(vport))
  		goto exit_unlock_free;
  
  	if (a[OVS_VPORT_ATTR_TYPE] &&
  	    nla_get_u32(a[OVS_VPORT_ATTR_TYPE]) != vport->ops->type) {
  		err = -EINVAL;
  		goto exit_unlock_free;
  	}
  
  	if (a[OVS_VPORT_ATTR_OPTIONS]) {
  		err = ovs_vport_set_options(vport, a[OVS_VPORT_ATTR_OPTIONS]);
  		if (err)
  			goto exit_unlock_free;
  	}
  
  
  	if (a[OVS_VPORT_ATTR_UPCALL_PID]) {
  		struct nlattr *ids = a[OVS_VPORT_ATTR_UPCALL_PID];
  
  		err = ovs_vport_set_upcall_portids(vport, ids);
  		if (err)
  			goto exit_unlock_free;
  	}
  
  	err = ovs_vport_cmd_fill_info(vport, reply, genl_info_net(info),
  				      info->snd_portid, info->snd_seq, 0,
  				      OVS_VPORT_CMD_SET);
  	BUG_ON(err < 0);
  
  	ovs_unlock();
  	ovs_notify(&dp_vport_genl_family, reply, info);
  	return 0;
  
  exit_unlock_free:
  	ovs_unlock();
  	kfree_skb(reply);
  	return err;
  }
  
  static int ovs_vport_cmd_del(struct sk_buff *skb, struct genl_info *info)
  {
  	bool must_update_headroom = false;
  	struct nlattr **a = info->attrs;
  	struct sk_buff *reply;
  	struct datapath *dp;
  	struct vport *vport;
  	int err;
  
  	reply = ovs_vport_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	ovs_lock();
  	vport = lookup_vport(sock_net(skb->sk), info->userhdr, a);
  	err = PTR_ERR(vport);
  	if (IS_ERR(vport))
  		goto exit_unlock_free;
  
  	if (vport->port_no == OVSP_LOCAL) {
  		err = -EINVAL;
  		goto exit_unlock_free;
  	}
  
  	err = ovs_vport_cmd_fill_info(vport, reply, genl_info_net(info),
  				      info->snd_portid, info->snd_seq, 0,
  				      OVS_VPORT_CMD_DEL);
  	BUG_ON(err < 0);
  
  	/* the vport deletion may trigger dp headroom update */
  	dp = vport->dp;
  	if (netdev_get_fwd_headroom(vport->dev) == dp->max_headroom)
  		must_update_headroom = true;
  	netdev_reset_rx_headroom(vport->dev);
  	ovs_dp_detach_port(vport);
  
  	if (must_update_headroom)
  		update_headroom(dp);
  	ovs_unlock();
  
  	ovs_notify(&dp_vport_genl_family, reply, info);
  	return 0;
  
  exit_unlock_free:
  	ovs_unlock();
  	kfree_skb(reply);
  	return err;
  }
  
  static int ovs_vport_cmd_get(struct sk_buff *skb, struct genl_info *info)
  {
  	struct nlattr **a = info->attrs;
  	struct ovs_header *ovs_header = info->userhdr;
  	struct sk_buff *reply;
  	struct vport *vport;
  	int err;
  
  	reply = ovs_vport_cmd_alloc_info();
  	if (!reply)
  		return -ENOMEM;
  
  	rcu_read_lock();
  	vport = lookup_vport(sock_net(skb->sk), ovs_header, a);
  	err = PTR_ERR(vport);
  	if (IS_ERR(vport))
  		goto exit_unlock_free;
  	err = ovs_vport_cmd_fill_info(vport, reply, genl_info_net(info),
  				      info->snd_portid, info->snd_seq, 0,
  				      OVS_VPORT_CMD_GET);
  	BUG_ON(err < 0);
  	rcu_read_unlock();
  
  	return genlmsg_reply(reply, info);
  
  exit_unlock_free:
  	rcu_read_unlock();
  	kfree_skb(reply);
  	return err;
  }
  
  static int ovs_vport_cmd_dump(struct sk_buff *skb, struct netlink_callback *cb)
  {
  	struct ovs_header *ovs_header = genlmsg_data(nlmsg_data(cb->nlh));
  	struct datapath *dp;
  	int bucket = cb->args[0], skip = cb->args[1];
  	int i, j = 0;
  
  	rcu_read_lock();
  	dp = get_dp_rcu(sock_net(skb->sk), ovs_header->dp_ifindex);
  	if (!dp) {
  		rcu_read_unlock();
  		return -ENODEV;
  	}
  	for (i = bucket; i < DP_VPORT_HASH_BUCKETS; i++) {
  		struct vport *vport;
  
  		j = 0;
  		hlist_for_each_entry_rcu(vport, &dp->ports[i], dp_hash_node) {
  			if (j >= skip &&
  			    ovs_vport_cmd_fill_info(vport, skb,
  						    sock_net(skb->sk),
  						    NETLINK_CB(cb->skb).portid,
  						    cb->nlh->nlmsg_seq,
  						    NLM_F_MULTI,
  						    OVS_VPORT_CMD_GET) < 0)
  				goto out;
  
  			j++;
  		}
  		skip = 0;
  	}
  out:
  	rcu_read_unlock();
  
  	cb->args[0] = i;
  	cb->args[1] = j;
  
  	return skb->len;
  }
  
  static const struct nla_policy vport_policy[OVS_VPORT_ATTR_MAX + 1] = {
  	[OVS_VPORT_ATTR_NAME] = { .type = NLA_NUL_STRING, .len = IFNAMSIZ - 1 },
  	[OVS_VPORT_ATTR_STATS] = { .len = sizeof(struct ovs_vport_stats) },
  	[OVS_VPORT_ATTR_PORT_NO] = { .type = NLA_U32 },
  	[OVS_VPORT_ATTR_TYPE] = { .type = NLA_U32 },
  	[OVS_VPORT_ATTR_UPCALL_PID] = { .type = NLA_U32 },
  	[OVS_VPORT_ATTR_OPTIONS] = { .type = NLA_NESTED },
  	[OVS_VPORT_ATTR_IFINDEX] = { .type = NLA_U32 },
  	[OVS_VPORT_ATTR_NETNSID] = { .type = NLA_S32 },
  };
  
  static const struct genl_ops dp_vport_genl_ops[] = {
  	{ .cmd = OVS_VPORT_CMD_NEW,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = vport_policy,
  	  .doit = ovs_vport_cmd_new
  	},
  	{ .cmd = OVS_VPORT_CMD_DEL,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = vport_policy,
  	  .doit = ovs_vport_cmd_del
  	},
  	{ .cmd = OVS_VPORT_CMD_GET,
  	  .flags = 0,		    /* OK for unprivileged users. */
  	  .policy = vport_policy,
  	  .doit = ovs_vport_cmd_get,
  	  .dumpit = ovs_vport_cmd_dump
  	},
  	{ .cmd = OVS_VPORT_CMD_SET,
  	  .flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */
  	  .policy = vport_policy,
  	  .doit = ovs_vport_cmd_set,
  	},
  };
  
  struct genl_family dp_vport_genl_family __ro_after_init = {
  	.hdrsize = sizeof(struct ovs_header),
  	.name = OVS_VPORT_FAMILY,
  	.version = OVS_VPORT_VERSION,
  	.maxattr = OVS_VPORT_ATTR_MAX,
  	.netnsok = true,
  	.parallel_ops = true,
  	.ops = dp_vport_genl_ops,
  	.n_ops = ARRAY_SIZE(dp_vport_genl_ops),
  	.mcgrps = &ovs_dp_vport_multicast_group,
  	.n_mcgrps = 1,
  	.module = THIS_MODULE,
  };
  
  static struct genl_family * const dp_genl_families[] = {
  	&dp_datapath_genl_family,
  	&dp_vport_genl_family,
  	&dp_flow_genl_family,
  	&dp_packet_genl_family,
  	&dp_meter_genl_family,
  #if	IS_ENABLED(CONFIG_NETFILTER_CONNCOUNT)
  	&dp_ct_limit_genl_family,
  #endif
  };
  
  static void dp_unregister_genl(int n_families)
  {
  	int i;
  
  	for (i = 0; i < n_families; i++)
  		genl_unregister_family(dp_genl_families[i]);
  }
  
  static int __init dp_register_genl(void)
  {
  	int err;
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(dp_genl_families); i++) {
  
  		err = genl_register_family(dp_genl_families[i]);
  		if (err)
  			goto error;
  	}
  
  	return 0;
  
  error:
  	dp_unregister_genl(i);
  	return err;
  }
  
  static int __net_init ovs_init_net(struct net *net)
  {
  	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
  
  	INIT_LIST_HEAD(&ovs_net->dps);
  	INIT_WORK(&ovs_net->dp_notify_work, ovs_dp_notify_wq);
  	return ovs_ct_init(net);
  }
  
  static void __net_exit list_vports_from_net(struct net *net, struct net *dnet,
  					    struct list_head *head)
  {
  	struct ovs_net *ovs_net = net_generic(net, ovs_net_id);
  	struct datapath *dp;
  
  	list_for_each_entry(dp, &ovs_net->dps, list_node) {
  		int i;
  
  		for (i = 0; i < DP_VPORT_HASH_BUCKETS; i++) {
  			struct vport *vport;
  
  			hlist_for_each_entry(vport, &dp->ports[i], dp_hash_node) {
  				if (vport->ops->type != OVS_VPORT_TYPE_INTERNAL)
  					continue;
  
  				if (dev_net(vport->dev) == dnet)
  					list_add(&vport->detach_list, head);
  			}
  		}
  	}
  }
  
  static void __net_exit ovs_exit_net(struct net *dnet)
  {
  	struct datapath *dp, *dp_next;
  	struct ovs_net *ovs_net = net_generic(dnet, ovs_net_id);
  	struct vport *vport, *vport_next;
  	struct net *net;
  	LIST_HEAD(head);
  
  	ovs_ct_exit(dnet);
  	ovs_lock();
  	list_for_each_entry_safe(dp, dp_next, &ovs_net->dps, list_node)
  		__dp_destroy(dp);
  
  	down_read(&net_rwsem);
  	for_each_net(net)
  		list_vports_from_net(net, dnet, &head);
  	up_read(&net_rwsem);
  
  	/* Detach all vports from given namespace. */
  	list_for_each_entry_safe(vport, vport_next, &head, detach_list) {
  		list_del(&vport->detach_list);
  		ovs_dp_detach_port(vport);
  	}
  
  	ovs_unlock();
  
  	cancel_work_sync(&ovs_net->dp_notify_work);
  }
  
  static struct pernet_operations ovs_net_ops = {
  	.init = ovs_init_net,
  	.exit = ovs_exit_net,
  	.id   = &ovs_net_id,
  	.size = sizeof(struct ovs_net),
  };
  
  static int __init dp_init(void)
  {
  	int err;
  
  	BUILD_BUG_ON(sizeof(struct ovs_skb_cb) > FIELD_SIZEOF(struct sk_buff, cb));
  
  	pr_info("Open vSwitch switching datapath\n");
  
  	err = action_fifos_init();
  	if (err)
  		goto error;
  
  	err = ovs_internal_dev_rtnl_link_register();
  	if (err)
  		goto error_action_fifos_exit;
  
  	err = ovs_flow_init();
  	if (err)
  		goto error_unreg_rtnl_link;
  
  	err = ovs_vport_init();
  	if (err)
  		goto error_flow_exit;
  
  	err = register_pernet_device(&ovs_net_ops);
  	if (err)
  		goto error_vport_exit;
  
  	err = register_netdevice_notifier(&ovs_dp_device_notifier);
  	if (err)
  		goto error_netns_exit;
  
  	err = ovs_netdev_init();
  	if (err)
  		goto error_unreg_notifier;
  
  	err = dp_register_genl();
  	if (err < 0)
  		goto error_unreg_netdev;
  
  	return 0;
  
  error_unreg_netdev:
  	ovs_netdev_exit();
  error_unreg_notifier:
  	unregister_netdevice_notifier(&ovs_dp_device_notifier);
  error_netns_exit:
  	unregister_pernet_device(&ovs_net_ops);
  error_vport_exit:
  	ovs_vport_exit();
  error_flow_exit:
  	ovs_flow_exit();
  error_unreg_rtnl_link:
  	ovs_internal_dev_rtnl_link_unregister();
  error_action_fifos_exit:
  	action_fifos_exit();
  error:
  	return err;
  }
  
  static void dp_cleanup(void)
  {
  	dp_unregister_genl(ARRAY_SIZE(dp_genl_families));
  	ovs_netdev_exit();
  	unregister_netdevice_notifier(&ovs_dp_device_notifier);
  	unregister_pernet_device(&ovs_net_ops);
  	rcu_barrier();
  	ovs_vport_exit();
  	ovs_flow_exit();
  	ovs_internal_dev_rtnl_link_unregister();
  	action_fifos_exit();
  }
  
  module_init(dp_init);
  module_exit(dp_cleanup);
  
  MODULE_DESCRIPTION("Open vSwitch switching datapath");
  MODULE_LICENSE("GPL");
  MODULE_ALIAS_GENL_FAMILY(OVS_DATAPATH_FAMILY);
  MODULE_ALIAS_GENL_FAMILY(OVS_VPORT_FAMILY);
  MODULE_ALIAS_GENL_FAMILY(OVS_FLOW_FAMILY);
  MODULE_ALIAS_GENL_FAMILY(OVS_PACKET_FAMILY);
  MODULE_ALIAS_GENL_FAMILY(OVS_METER_FAMILY);
  MODULE_ALIAS_GENL_FAMILY(OVS_CT_LIMIT_FAMILY);
  