diff options
Diffstat (limited to 'net/ipv4/udp_offload.c')
| -rw-r--r-- | net/ipv4/udp_offload.c | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 79c62bdcd3c5..88b4023ecfcf 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -14,6 +14,17 @@ #include <net/udp.h> #include <net/protocol.h> +static DEFINE_SPINLOCK(udp_offload_lock); +static struct udp_offload_priv __rcu *udp_offload_base __read_mostly; + +#define udp_deref_protected(X) rcu_dereference_protected(X, lockdep_is_held(&udp_offload_lock)) + +struct udp_offload_priv { + struct udp_offload *offload; + struct rcu_head rcu; + struct udp_offload_priv __rcu *next; +}; + static int udp4_ufo_send_check(struct sk_buff *skb) { if (!pskb_may_pull(skb, sizeof(struct udphdr))) @@ -89,10 +100,143 @@ out: return segs; } +int udp_add_offload(struct udp_offload *uo) +{ + struct udp_offload_priv *new_offload = kzalloc(sizeof(*new_offload), GFP_ATOMIC); + + if (!new_offload) + return -ENOMEM; + + new_offload->offload = uo; + + spin_lock(&udp_offload_lock); + new_offload->next = udp_offload_base; + rcu_assign_pointer(udp_offload_base, new_offload); + spin_unlock(&udp_offload_lock); + + return 0; +} +EXPORT_SYMBOL(udp_add_offload); + +static void udp_offload_free_routine(struct rcu_head *head) +{ + struct udp_offload_priv *ou_priv = container_of(head, struct udp_offload_priv, rcu); + kfree(ou_priv); +} + +void udp_del_offload(struct udp_offload *uo) +{ + struct udp_offload_priv __rcu **head = &udp_offload_base; + struct udp_offload_priv *uo_priv; + + spin_lock(&udp_offload_lock); + + uo_priv = udp_deref_protected(*head); + for (; uo_priv != NULL; + uo_priv = udp_deref_protected(*head)) { + if (uo_priv->offload == uo) { + rcu_assign_pointer(*head, + udp_deref_protected(uo_priv->next)); + goto unlock; + } + head = &uo_priv->next; + } + pr_warn("udp_del_offload: didn't find offload for port %d\n", ntohs(uo->port)); +unlock: + spin_unlock(&udp_offload_lock); + if (uo_priv != NULL) + call_rcu(&uo_priv->rcu, udp_offload_free_routine); +} +EXPORT_SYMBOL(udp_del_offload); + +static struct sk_buff **udp_gro_receive(struct sk_buff **head, struct sk_buff *skb) +{ + struct udp_offload_priv *uo_priv; + struct sk_buff *p, **pp = NULL; + struct udphdr *uh, *uh2; + unsigned int hlen, off; + int flush = 1; + + if (NAPI_GRO_CB(skb)->udp_mark || + (!skb->encapsulation && skb->ip_summed != CHECKSUM_COMPLETE)) + goto out; + + /* mark that this skb passed once through the udp gro layer */ + NAPI_GRO_CB(skb)->udp_mark = 1; + + off = skb_gro_offset(skb); + hlen = off + sizeof(*uh); + uh = skb_gro_header_fast(skb, off); + if (skb_gro_header_hard(skb, hlen)) { + uh = skb_gro_header_slow(skb, hlen, off); + if (unlikely(!uh)) + goto out; + } + + rcu_read_lock(); + uo_priv = rcu_dereference(udp_offload_base); + for (; uo_priv != NULL; uo_priv = rcu_dereference(uo_priv->next)) { + if (uo_priv->offload->port == uh->dest && + uo_priv->offload->callbacks.gro_receive) + goto unflush; + } + goto out_unlock; + +unflush: + flush = 0; + + for (p = *head; p; p = p->next) { + if (!NAPI_GRO_CB(p)->same_flow) + continue; + + uh2 = (struct udphdr *)(p->data + off); + if ((*(u32 *)&uh->source != *(u32 *)&uh2->source)) { + NAPI_GRO_CB(p)->same_flow = 0; + continue; + } + } + + skb_gro_pull(skb, sizeof(struct udphdr)); /* pull encapsulating udp header */ + pp = uo_priv->offload->callbacks.gro_receive(head, skb); + +out_unlock: + rcu_read_unlock(); +out: + NAPI_GRO_CB(skb)->flush |= flush; + return pp; +} + +static int udp_gro_complete(struct sk_buff *skb, int nhoff) +{ + struct udp_offload_priv *uo_priv; + __be16 newlen = htons(skb->len - nhoff); + struct udphdr *uh = (struct udphdr *)(skb->data + nhoff); + int err = -ENOSYS; + + uh->len = newlen; + + rcu_read_lock(); + + uo_priv = rcu_dereference(udp_offload_base); + for (; uo_priv != NULL; uo_priv = rcu_dereference(uo_priv->next)) { + if (uo_priv->offload->port == uh->dest && + uo_priv->offload->callbacks.gro_complete) + break; + } + + if (uo_priv != NULL) + err = uo_priv->offload->callbacks.gro_complete(skb, nhoff + sizeof(struct udphdr)); + + rcu_read_unlock(); + return err; +} + static const struct net_offload udpv4_offload = { .callbacks = { .gso_send_check = udp4_ufo_send_check, .gso_segment = udp4_ufo_fragment, + .gro_receive = udp_gro_receive, + .gro_complete = udp_gro_complete, }, }; |