From: Jussi Maki joamaki@gmail.com
In preparation for adding XDP support to the bonding driver refactor the packet hashing functions to be able to work with any linear data buffer without an skb.
Signed-off-by: Jussi Maki joamaki@gmail.com Signed-off-by: Daniel Borkmann daniel@iogearbox.net Cc: Jay Vosburgh j.vosburgh@gmail.com Cc: Veaceslav Falico vfalico@gmail.com Cc: Andy Gospodarek andy@greyhouse.net Link: https://lore.kernel.org/bpf/20210731055738.16820-2-joamaki@gmail.com
Conflicts: drivers/net/bonding/bond_main.c
Signed-off-by: Zhengchao Shao shaozhengchao@huawei.com --- drivers/net/bonding/bond_main.c | 136 +++++++++++++++++++------------- 1 file changed, 81 insertions(+), 55 deletions(-)
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 16100672149e..ed88282ddff4 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -3601,66 +3601,84 @@ static struct notifier_block bond_netdev_notifier = { };
/*---------------------------- Hashing Policies -----------------------------*/ +/* Helper to access data in a packet, with or without a backing skb. + * If skb is given the data is linearized if necessary via pskb_may_pull. + */ +static inline void *bond_pull_data(struct sk_buff *skb, + void *data, int hlen, int n) +{ + if (likely(n <= hlen)) + return data; + else if (skb && likely(pskb_may_pull(skb, n))) + return skb->head; + + return NULL; +}
/* L2 hash helper */ -static inline u32 bond_eth_hash(struct sk_buff *skb) +static inline u32 bond_eth_hash(struct sk_buff *skb, void *data, int mhoff, int hlen) { - struct ethhdr *ep, hdr_tmp; + struct ethhdr *ep;
- ep = skb_header_pointer(skb, 0, sizeof(hdr_tmp), &hdr_tmp); - if (ep) - return ep->h_dest[5] ^ ep->h_source[5] ^ ep->h_proto; - return 0; + data = bond_pull_data(skb, data, hlen, mhoff + sizeof(struct ethhdr)); + if (!data) + return 0; + + ep = (struct ethhdr *)(data + mhoff); + return ep->h_dest[5] ^ ep->h_source[5] ^ ep->h_proto; }
-static bool bond_flow_ip(struct sk_buff *skb, struct flow_keys *fk, - int *noff, int *proto, bool l34) +static bool bond_flow_ip(struct sk_buff *skb, struct flow_keys *fk, void *data, + int hlen, __be16 l2_proto, int *nhoff, int *ip_proto, bool l34) { const struct ipv6hdr *iph6; const struct iphdr *iph;
- if (skb->protocol == htons(ETH_P_IP)) { - if (unlikely(!pskb_may_pull(skb, *noff + sizeof(*iph)))) + if (l2_proto == htons(ETH_P_IP)) { + data = bond_pull_data(skb, data, hlen, *nhoff + sizeof(*iph)); + if (!data) return false; - iph = (const struct iphdr *)(skb->data + *noff); + + iph = (const struct iphdr *)(data + *nhoff); iph_to_flow_copy_v4addrs(fk, iph); - *noff += iph->ihl << 2; + *nhoff += iph->ihl << 2; if (!ip_is_fragment(iph)) - *proto = iph->protocol; - } else if (skb->protocol == htons(ETH_P_IPV6)) { - if (unlikely(!pskb_may_pull(skb, *noff + sizeof(*iph6)))) + *ip_proto = iph->protocol; + } else if (l2_proto == htons(ETH_P_IPV6)) { + data = bond_pull_data(skb, data, hlen, *nhoff + sizeof(*iph6)); + if (!data) return false; - iph6 = (const struct ipv6hdr *)(skb->data + *noff); + + iph6 = (const struct ipv6hdr *)(data + *nhoff); iph_to_flow_copy_v6addrs(fk, iph6); - *noff += sizeof(*iph6); - *proto = iph6->nexthdr; + *nhoff += sizeof(*iph6); + *ip_proto = iph6->nexthdr; } else { return false; }
- if (l34 && *proto >= 0) - fk->ports.ports = skb_flow_get_ports(skb, *noff, *proto); + if (l34 && *ip_proto >= 0) + fk->ports.ports = __skb_flow_get_ports(skb, *nhoff, *ip_proto, data, hlen);
return true; }
/* Extract the appropriate headers based on bond's xmit policy */ -static bool bond_flow_dissect(struct bonding *bond, struct sk_buff *skb, - struct flow_keys *fk) +static bool bond_flow_dissect(struct bonding *bond, struct sk_buff *skb, void *data, + __be16 l2_proto, int nhoff, int hlen, struct flow_keys *fk) { bool l34 = bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34; - int noff, proto = -1; + int ip_proto = -1;
if (bond->params.xmit_policy > BOND_XMIT_POLICY_LAYER23) { memset(fk, 0, sizeof(*fk)); return __skb_flow_dissect(NULL, skb, &flow_keys_bonding, - fk, NULL, 0, 0, 0, 0); + fk, data, l2_proto, nhoff, hlen, 0); }
fk->ports.ports = 0; memset(&fk->icmp, 0, sizeof(fk->icmp)); - noff = skb_network_offset(skb); - if (!bond_flow_ip(skb, fk, &noff, &proto, l34)) + if (!bond_flow_ip(skb, fk, data, hlen, l2_proto, &nhoff, &ip_proto, l34)) return false;
/* ICMP error packets contains at least 8 bytes of the header @@ -3668,51 +3686,41 @@ static bool bond_flow_dissect(struct bonding *bond, struct sk_buff *skb, * to correlate ICMP error packets within the same flow which * generated the error. */ - if (proto == IPPROTO_ICMP || proto == IPPROTO_ICMPV6) { - skb_flow_get_icmp_tci(skb, &fk->icmp, skb->data, - skb_transport_offset(skb), - skb_headlen(skb)); - if (proto == IPPROTO_ICMP) { + if (ip_proto == IPPROTO_ICMP || ip_proto == IPPROTO_ICMPV6) { + skb_flow_get_icmp_tci(skb, &fk->icmp, data, nhoff, hlen); + if (ip_proto == IPPROTO_ICMP) { if (!icmp_is_err(fk->icmp.type)) return true;
- noff += sizeof(struct icmphdr); - } else if (proto == IPPROTO_ICMPV6) { + nhoff += sizeof(struct icmphdr); + } else if (ip_proto == IPPROTO_ICMPV6) { if (!icmpv6_is_err(fk->icmp.type)) return true;
- noff += sizeof(struct icmp6hdr); + nhoff += sizeof(struct icmp6hdr); } - return bond_flow_ip(skb, fk, &noff, &proto, l34); + return bond_flow_ip(skb, fk, data, hlen, l2_proto, &nhoff, &ip_proto, l34); }
return true; } - -/** - * bond_xmit_hash - generate a hash value based on the xmit policy - * @bond: bonding device - * @skb: buffer to use for headers - * - * This function will extract the necessary headers from the skb buffer and use - * them to generate a hash based on the xmit_policy set in the bonding device +/* Generate hash based on xmit policy. If @skb is given it is used to linearize + * the data as required, but this function can be used without it if the data is + * known to be linear (e.g. with xdp_buff). */ -u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb) +static u32 __bond_xmit_hash(struct bonding *bond, struct sk_buff *skb, void *data, + __be16 l2_proto, int mhoff, int nhoff, int hlen) { struct flow_keys flow; u32 hash;
- if (bond->params.xmit_policy == BOND_XMIT_POLICY_ENCAP34 && - skb->l4_hash) - return skb->hash; - if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER2 || - !bond_flow_dissect(bond, skb, &flow)) - return bond_eth_hash(skb); + !bond_flow_dissect(bond, skb, data, l2_proto, nhoff, hlen, &flow)) + return bond_eth_hash(skb, data, mhoff, hlen);
if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER23 || bond->params.xmit_policy == BOND_XMIT_POLICY_ENCAP23) { - hash = bond_eth_hash(skb); + hash = bond_eth_hash(skb, data, mhoff, hlen); } else { if (flow.icmp.id) memcpy(&hash, &flow.icmp, sizeof(hash)); @@ -3727,6 +3735,25 @@ u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb) return hash >> 1; }
+/** + * bond_xmit_hash - generate a hash value based on the xmit policy + * @bond: bonding device + * @skb: buffer to use for headers + * + * This function will extract the necessary headers from the skb buffer and use + * them to generate a hash based on the xmit_policy set in the bonding device + */ +u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb) +{ + if (bond->params.xmit_policy == BOND_XMIT_POLICY_ENCAP34 && + skb->l4_hash) + return skb->hash; + + return __bond_xmit_hash(bond, skb, skb->head, skb->protocol, + skb->mac_header, skb->network_header, + skb_headlen(skb)); +} + /*-------------------------- Device entry points ----------------------------*/
void bond_work_init_all(struct bonding *bond) @@ -4373,8 +4400,7 @@ static netdev_tx_t bond_xmit_roundrobin(struct sk_buff *skb, return bond_tx_drop(bond_dev, skb); }
-static struct slave *bond_xmit_activebackup_slave_get(struct bonding *bond, - struct sk_buff *skb) +static struct slave *bond_xmit_activebackup_slave_get(struct bonding *bond) { return rcu_dereference(bond->curr_active_slave); } @@ -4388,7 +4414,7 @@ static netdev_tx_t bond_xmit_activebackup(struct sk_buff *skb, struct bonding *bond = netdev_priv(bond_dev); struct slave *slave;
- slave = bond_xmit_activebackup_slave_get(bond, skb); + slave = bond_xmit_activebackup_slave_get(bond); if (slave) return bond_dev_queue_xmit(bond, skb, slave->dev);
@@ -4700,7 +4726,7 @@ static struct net_device *bond_xmit_get_slave(struct net_device *master_dev, slave = bond_xmit_roundrobin_slave_get(bond, skb); break; case BOND_MODE_ACTIVEBACKUP: - slave = bond_xmit_activebackup_slave_get(bond, skb); + slave = bond_xmit_activebackup_slave_get(bond); break; case BOND_MODE_8023AD: case BOND_MODE_XOR: