static int output_userspace(struct datapath *dp, struct sk_buff *skb,
const struct nlattr *attr)
{
struct dp_upcall_info upcall;
const struct nlattr *a;
int rem;
upcall.cmd = OVS_PACKET_CMD_ACTION;
upcall.key = &OVS_CB(skb)->flow->key;
upcall.userdata = NULL;
upcall.pid = 0;
for (a = nla_data(attr), rem = nla_len(attr); rem > 0;
a = nla_next(a, &rem)) {
switch (nla_type(a)) {
case OVS_USERSPACE_ATTR_USERDATA:
upcall.userdata = a;
break;
case OVS_USERSPACE_ATTR_PID:
upcall.pid = nla_get_u32(a);
break;
}
}
return ovs_dp_upcall(dp, skb, &upcall);
}
/* called from BPF program, therefore rcu_read_lock is held
* bpf_check() verified that 'buf' pointer to BPF's stack
* and it has 'len' bytes for us to read
*/
void bpf_channel_push_struct(struct bpf_context *pctx, u32 struct_id,
const void *buf, u32 len)
{
struct bpf_dp_context *ctx = container_of(pctx, struct bpf_dp_context,
context);
struct dp_upcall_info upcall;
struct plum *plum;
struct nlattr *nla;
if (unlikely(!ctx->skb))
return;
plum = rcu_dereference(ctx->dp->plums[pctx->plum_id]);
if (unlikely(!plum))
return;
/* allocate temp nlattr to pass it into ovs_dp_upcall */
nla = kzalloc(nla_total_size(4 + len), GFP_ATOMIC);
if (unlikely(!nla))
return;
nla->nla_type = OVS_PACKET_ATTR_USERDATA;
nla->nla_len = nla_attr_size(4 + len);
memcpy(nla_data(nla), &struct_id, 4);
memcpy(nla_data(nla) + 4, buf, len);
upcall.cmd = OVS_PACKET_CMD_ACTION;
upcall.key = NULL;
upcall.userdata = nla;
upcall.portid = plum->upcall_pid;
ovs_dp_upcall(ctx->dp, NULL, &upcall);
kfree(nla);
}
/* Must be called with rcu_read_lock. */
void ovs_dp_process_received_packet(struct vport *p, struct sk_buff *skb)
{
struct datapath *dp = p->dp;
struct sw_flow *flow;
struct dp_stats_percpu *stats;
u64 *stats_counter;
int error;
stats = per_cpu_ptr(dp->stats_percpu, smp_processor_id());
if (!OVS_CB(skb)->flow) {
struct sw_flow_key key;
int key_len;
/* Extract flow from 'skb' into 'key'. */
error = ovs_flow_extract(skb, p->port_no, &key, &key_len);
if (unlikely(error)) {
kfree_skb(skb);
return;
}
/* Look up flow. */
flow = ovs_flow_tbl_lookup(rcu_dereference(dp->table),
&key, key_len);
if (unlikely(!flow)) {
struct dp_upcall_info upcall;
upcall.cmd = OVS_PACKET_CMD_MISS;
upcall.key = &key;
upcall.userdata = NULL;
upcall.pid = p->upcall_pid;
ovs_dp_upcall(dp, skb, &upcall);
consume_skb(skb);
stats_counter = &stats->n_missed;
goto out;
}
OVS_CB(skb)->flow = flow;
}
stats_counter = &stats->n_hit;
ovs_flow_used(OVS_CB(skb)->flow, skb);
ovs_execute_actions(dp, skb);
out:
/* Update datapath statistics. */
u64_stats_update_begin(&stats->sync);
(*stats_counter)++;
u64_stats_update_end(&stats->sync);
}
/* called from BPF program, therefore rcu_read_lock is held */
void bpf_channel_push_packet(struct bpf_context *pctx)
{
struct bpf_dp_context *ctx = container_of(pctx, struct bpf_dp_context,
context);
struct dp_upcall_info upcall;
struct sk_buff *nskb;
struct plum *plum;
if (unlikely(!ctx->skb))
return;
plum = rcu_dereference(ctx->dp->plums[pctx->plum_id]);
if (unlikely(!plum))
return;
/* queue_gso_packets() inside ovs_dp_upcall() changes skb,
* so copy it here, since BPF program might still be using it
*/
nskb = skb_clone(ctx->skb, GFP_ATOMIC);
if (unlikely(!nskb))
return;
upcall.cmd = OVS_PACKET_CMD_ACTION;
upcall.key = NULL;
upcall.userdata = NULL;
upcall.portid = plum->upcall_pid;
/* don't exit earlier even if upcall_pid is invalid,
* since we want 'lost' count to be incremented
*/
/* disable softirq to make sure that genlmsg_unicast()->gfp_any() picks
* GFP_ATOMIC flag
* note that bpf_channel_push_struct() doesn't need to do it,
* since skb==NULL
*/
local_bh_disable();
ovs_dp_upcall(ctx->dp, nskb, &upcall);
local_bh_enable();
consume_skb(nskb);
}