// SPDX-License-Identifier: GPL-2.0-only

/*

* Copyright (c) 2007-2014 Nicira, Inc.

*/

#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/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/gso.h>

#include <net/net_namespace.h>

#include <net/netns/generic.h>

#include <net/pkt_cls.h>

#include "datapath.h"

#include "drop.h"

#include "flow.h"

#include "flow_table.h"

#include "flow_netlink.h"

#include "meter.h"

#include "openvswitch_trace.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);

static void ovs_dp_masks_rebalance(struct work_struct *work);

static int ovs_dp_set_upcall_portids(struct datapath *, const struct nlattr *);

/* 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(rcu_dereference_raw(dp->upcall_portids));

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,

lockdep_ovsl_is_held()) {

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;

}

static void ovs_vport_update_upcall_stats(struct sk_buff *skb,

const struct dp_upcall_info *upcall_info,

bool upcall_result)

{

struct vport *p = OVS_CB(skb)->input_vport;

struct vport_upcall_stats_percpu *stats;

if (upcall_info->cmd != OVS_PACKET_CMD_MISS &&

upcall_info->cmd != OVS_PACKET_CMD_ACTION)

return;

stats = this_cpu_ptr(p->upcall_stats);

u64_stats_update_begin(&stats->syncp);

if (upcall_result)

u64_stats_inc(&stats->n_success);

else

u64_stats_inc(&stats->n_fail);

u64_stats_update_end(&stats->syncp);

}

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)

{

struct ovs_pcpu_storage *ovs_pcpu = this_cpu_ptr(ovs_pcpu_storage);

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;

bool ovs_pcpu_locked = false;

u64 *stats_counter;

u32 n_mask_hit;

u32 n_cache_hit;

int error;

stats = this_cpu_ptr(dp->stats_percpu);

/* Look up flow. */

flow = ovs_flow_tbl_lookup_stats(&dp->table, key, skb_get_hash(skb),

&n_mask_hit, &n_cache_hit);

if (unlikely(!flow)) {

struct dp_upcall_info upcall;

memset(&upcall, 0, sizeof(upcall));

upcall.cmd = OVS_PACKET_CMD_MISS;

if (OVS_CB(skb)->upcall_pid)

upcall.portid = OVS_CB(skb)->upcall_pid;

else if (dp->user_features & OVS_DP_F_DISPATCH_UPCALL_PER_CPU)

upcall.portid =

ovs_dp_get_upcall_portid(dp, smp_processor_id());

else

upcall.portid = ovs_vport_find_upcall_portid(p, skb);

upcall.mru = OVS_CB(skb)->mru;

error = ovs_dp_upcall(dp, skb, key, &upcall, 0);

switch (error) {

case 0:

case -EAGAIN:

case -ERESTARTSYS:

case -EINTR:

consume_skb(skb);

break;

default:

kfree_skb(skb);

break;

}

stats_counter = &stats->n_missed;

goto out;

}

ovs_flow_stats_update(flow, key->tp.flags, skb);

sf_acts = rcu_dereference(flow->sf_acts);

/* This path can be invoked recursively: Use the current task to

* identify recursive invocation - the lock must be acquired only once.

* Even with disabled bottom halves this can be preempted on PREEMPT_RT.

* Limit the locking to RT to avoid assigning `owner' if it can be

* avoided.

*/

if (IS_ENABLED(CONFIG_PREEMPT_RT) && ovs_pcpu->owner != current) {

local_lock_nested_bh(&ovs_pcpu_storage->bh_lock);

ovs_pcpu->owner = current;

ovs_pcpu_locked = true;

}

error = ovs_execute_actions(dp, skb, sf_acts, key);

if (unlikely(error))

net_dbg_ratelimited("ovs: action execution error on datapath %s: %d\n",

ovs_dp_name(dp), error);

if (ovs_pcpu_locked) {

ovs_pcpu->owner = NULL;

local_unlock_nested_bh(&ovs_pcpu_storage->bh_lock);

}

stats_counter = &stats->n_hit;

out:

/* Update datapath statistics. */

u64_stats_update_begin(&stats->syncp);

(*stats_counter)++;

stats->n_mask_hit += n_mask_hit;

stats->n_cache_hit += n_cache_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 (trace_ovs_dp_upcall_enabled())

trace_ovs_dp_upcall(dp, skb, key, upcall_info);

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);

ovs_vport_update_upcall_stats(skb, upcall_info, !err);

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_GSO_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_list_walk_safe(segs, skb, nskb) {

if (gso_type & SKB_GSO_UDP && skb != segs)

key = &later_key;

err = queue_userspace_packet(dp, skb, key, upcall_info, cutlen);

if (err)

break;

}

/* Free all of the segments. */

skb_list_walk_safe(segs, skb, nskb) {

if (err)

kfree_skb(skb);

else

consume_skb(skb);

}

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 */

+ nla_total_size(sizeof(u64)); /* OVS_PACKET_ATTR_HASH */

/* 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;

u64 hash;

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);

if (!upcall) {

err = -EINVAL;

goto out;

}

upcall->dp_ifindex = dp_ifindex;

err = ovs_nla_put_key(key, key, OVS_PACKET_ATTR_KEY, false, user_skb);

if (err)

goto out;

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_noflag(user_skb,

OVS_PACKET_ATTR_EGRESS_TUN_KEY);

if (!nla) {

err = -EMSGSIZE;

goto out;

}

err = ovs_nla_put_tunnel_info(user_skb,

upcall_info->egress_tun_info);

if (err)

goto out;

nla_nest_end(user_skb, nla);

}

if (upcall_info->actions_len) {

nla = nla_nest_start_noflag(user_skb, OVS_PACKET_ATTR_ACTIONS);

if (!nla) {

err = -EMSGSIZE;

goto out;

}

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 &&

nla_put_u16(user_skb, OVS_PACKET_ATTR_MRU, upcall_info->mru)) {

err = -ENOBUFS;

goto out;

}

/* Add OVS_PACKET_ATTR_LEN when packet is truncated */

if (cutlen > 0 &&

nla_put_u32(user_skb, OVS_PACKET_ATTR_LEN, skb->len)) {

err = -ENOBUFS;

goto out;

}

/* Add OVS_PACKET_ATTR_HASH */

hash = skb_get_hash_raw(skb);

if (skb->sw_hash)

hash |= OVS_PACKET_HASH_SW_BIT;

if (skb->l4_hash)

hash |= OVS_PACKET_HASH_L4_BIT;

if (nla_put(user_skb, OVS_PACKET_ATTR_HASH, sizeof (u64), &hash)) {

err = -ENOBUFS;

goto out;

}

/* 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);

consume_skb(user_skb);

consume_skb(nskb);

return err;

}

static int ovs_packet_cmd_execute(struct sk_buff *skb, struct genl_info *info)

{

struct ovs_header *ovs_header = genl_info_userhdr(info);

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;

u64 hash;

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;

if (a[OVS_PACKET_ATTR_HASH]) {

hash = nla_get_u64(a[OVS_PACKET_ATTR_HASH]);

__skb_set_hash(packet, hash & 0xFFFFFFFFULL,

!!(hash & OVS_PACKET_HASH_SW_BIT),

!!(hash & OVS_PACKET_HASH_L4_BIT));

}

OVS_CB(packet)->upcall_pid =

nla_get_u32_default(a[OVS_PACKET_ATTR_UPCALL_PID], 0);

/* 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();

local_lock_nested_bh(&ovs_pcpu_storage->bh_lock);

if (IS_ENABLED(CONFIG_PREEMPT_RT))

this_cpu_write(ovs_pcpu_storage->owner, current);

err = ovs_execute_actions(dp, packet, sf_acts, &flow->key);

if (IS_ENABLED(CONFIG_PREEMPT_RT))

this_cpu_write(ovs_pcpu_storage->owner, NULL);

local_unlock_nested_bh(&ovs_pcpu_storage->bh_lock);

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 },

[OVS_PACKET_ATTR_HASH] = { .type = NLA_U64 },

[OVS_PACKET_ATTR_UPCALL_PID] = { .type = NLA_U32 },

};

static const struct genl_small_ops dp_packet_genl_ops[] = {

{ .cmd = OVS_PACKET_CMD_EXECUTE,

.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,

.flags = GENL_UNS_ADMIN_PERM, /* Requires CAP_NET_ADMIN privilege. */

.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,

.policy = packet_policy,

.netnsok = true,

.parallel_ops = true,

.small_ops = dp_packet_genl_ops,

.n_small_ops = ARRAY_SIZE(dp_packet_genl_ops),

.resv_start_op = OVS_PACKET_CMD_EXECUTE + 1,

.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(&percpu_stats->syncp);

local_stats = *percpu_stats;

} while (u64_stats_fetch_retry(&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;

mega_stats->n_cache_hit += local_stats.n_cache_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, or unmasked flow key as fallback

* see ovs_nla_put_identifier()

*/

if (sfid && ovs_identifier_is_ufid(sfid))

len += nla_total_size(sfid->ufid_len);

else

len += nla_total_size(ovs_key_attr_size());

/* 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_noflag(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);

if (WARN_ON_ONCE(retval < 0)) {

kfree_skb(skb);

skb = ERR_PTR(retval);

}

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 = genl_info_userhdr(info);

struct sw_flow *flow = NULL, *new_flow;