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author | 2015-08-04 12:17:53 -0700 | |
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committer | 2015-08-04 15:44:42 -0700 | |
commit | 9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch) | |
tree | 1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/net/core/flow_dissector.c | |
parent | 98260f3884f4a202f9ca5eabed40b1354c489b29 (diff) |
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base.
It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:
commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date: Sat Jul 25 12:13:34 2015 +0200
Prepare v4.1.3-rt3
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.
Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/net/core/flow_dissector.c')
-rw-r--r-- | kernel/net/core/flow_dissector.c | 490 |
1 files changed, 490 insertions, 0 deletions
diff --git a/kernel/net/core/flow_dissector.c b/kernel/net/core/flow_dissector.c new file mode 100644 index 000000000..2c35c02a9 --- /dev/null +++ b/kernel/net/core/flow_dissector.c @@ -0,0 +1,490 @@ +#include <linux/skbuff.h> +#include <linux/export.h> +#include <linux/ip.h> +#include <linux/ipv6.h> +#include <linux/if_vlan.h> +#include <net/ip.h> +#include <net/ipv6.h> +#include <linux/igmp.h> +#include <linux/icmp.h> +#include <linux/sctp.h> +#include <linux/dccp.h> +#include <linux/if_tunnel.h> +#include <linux/if_pppox.h> +#include <linux/ppp_defs.h> +#include <net/flow_keys.h> +#include <scsi/fc/fc_fcoe.h> + +/* copy saddr & daddr, possibly using 64bit load/store + * Equivalent to : flow->src = iph->saddr; + * flow->dst = iph->daddr; + */ +static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *iph) +{ + BUILD_BUG_ON(offsetof(typeof(*flow), dst) != + offsetof(typeof(*flow), src) + sizeof(flow->src)); + memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst)); +} + +/** + * __skb_flow_get_ports - extract the upper layer ports and return them + * @skb: sk_buff to extract the ports from + * @thoff: transport header offset + * @ip_proto: protocol for which to get port offset + * @data: raw buffer pointer to the packet, if NULL use skb->data + * @hlen: packet header length, if @data is NULL use skb_headlen(skb) + * + * The function will try to retrieve the ports at offset thoff + poff where poff + * is the protocol port offset returned from proto_ports_offset + */ +__be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto, + void *data, int hlen) +{ + int poff = proto_ports_offset(ip_proto); + + if (!data) { + data = skb->data; + hlen = skb_headlen(skb); + } + + if (poff >= 0) { + __be32 *ports, _ports; + + ports = __skb_header_pointer(skb, thoff + poff, + sizeof(_ports), data, hlen, &_ports); + if (ports) + return *ports; + } + + return 0; +} +EXPORT_SYMBOL(__skb_flow_get_ports); + +/** + * __skb_flow_dissect - extract the flow_keys struct and return it + * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified + * @data: raw buffer pointer to the packet, if NULL use skb->data + * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol + * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb) + * @hlen: packet header length, if @data is NULL use skb_headlen(skb) + * + * The function will try to retrieve the struct flow_keys from either the skbuff + * or a raw buffer specified by the rest parameters + */ +bool __skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow, + void *data, __be16 proto, int nhoff, int hlen) +{ + u8 ip_proto; + + if (!data) { + data = skb->data; + proto = skb->protocol; + nhoff = skb_network_offset(skb); + hlen = skb_headlen(skb); + } + + memset(flow, 0, sizeof(*flow)); + +again: + switch (proto) { + case htons(ETH_P_IP): { + const struct iphdr *iph; + struct iphdr _iph; +ip: + iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph); + if (!iph || iph->ihl < 5) + return false; + nhoff += iph->ihl * 4; + + ip_proto = iph->protocol; + if (ip_is_fragment(iph)) + ip_proto = 0; + + /* skip the address processing if skb is NULL. The assumption + * here is that if there is no skb we are not looking for flow + * info but lengths and protocols. + */ + if (!skb) + break; + + iph_to_flow_copy_addrs(flow, iph); + break; + } + case htons(ETH_P_IPV6): { + const struct ipv6hdr *iph; + struct ipv6hdr _iph; + __be32 flow_label; + +ipv6: + iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph); + if (!iph) + return false; + + ip_proto = iph->nexthdr; + nhoff += sizeof(struct ipv6hdr); + + /* see comment above in IPv4 section */ + if (!skb) + break; + + flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr); + flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr); + + flow_label = ip6_flowlabel(iph); + if (flow_label) { + /* Awesome, IPv6 packet has a flow label so we can + * use that to represent the ports without any + * further dissection. + */ + flow->n_proto = proto; + flow->ip_proto = ip_proto; + flow->ports = flow_label; + flow->thoff = (u16)nhoff; + + return true; + } + + break; + } + case htons(ETH_P_8021AD): + case htons(ETH_P_8021Q): { + const struct vlan_hdr *vlan; + struct vlan_hdr _vlan; + + vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan), data, hlen, &_vlan); + if (!vlan) + return false; + + proto = vlan->h_vlan_encapsulated_proto; + nhoff += sizeof(*vlan); + goto again; + } + case htons(ETH_P_PPP_SES): { + struct { + struct pppoe_hdr hdr; + __be16 proto; + } *hdr, _hdr; + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); + if (!hdr) + return false; + proto = hdr->proto; + nhoff += PPPOE_SES_HLEN; + switch (proto) { + case htons(PPP_IP): + goto ip; + case htons(PPP_IPV6): + goto ipv6; + default: + return false; + } + } + case htons(ETH_P_TIPC): { + struct { + __be32 pre[3]; + __be32 srcnode; + } *hdr, _hdr; + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); + if (!hdr) + return false; + flow->src = hdr->srcnode; + flow->dst = 0; + flow->n_proto = proto; + flow->thoff = (u16)nhoff; + return true; + } + case htons(ETH_P_FCOE): + flow->thoff = (u16)(nhoff + FCOE_HEADER_LEN); + /* fall through */ + default: + return false; + } + + switch (ip_proto) { + case IPPROTO_GRE: { + struct gre_hdr { + __be16 flags; + __be16 proto; + } *hdr, _hdr; + + hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); + if (!hdr) + return false; + /* + * Only look inside GRE if version zero and no + * routing + */ + if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) { + proto = hdr->proto; + nhoff += 4; + if (hdr->flags & GRE_CSUM) + nhoff += 4; + if (hdr->flags & GRE_KEY) + nhoff += 4; + if (hdr->flags & GRE_SEQ) + nhoff += 4; + if (proto == htons(ETH_P_TEB)) { + const struct ethhdr *eth; + struct ethhdr _eth; + + eth = __skb_header_pointer(skb, nhoff, + sizeof(_eth), + data, hlen, &_eth); + if (!eth) + return false; + proto = eth->h_proto; + nhoff += sizeof(*eth); + } + goto again; + } + break; + } + case IPPROTO_IPIP: + proto = htons(ETH_P_IP); + goto ip; + case IPPROTO_IPV6: + proto = htons(ETH_P_IPV6); + goto ipv6; + default: + break; + } + + flow->n_proto = proto; + flow->ip_proto = ip_proto; + flow->thoff = (u16) nhoff; + + /* unless skb is set we don't need to record port info */ + if (skb) + flow->ports = __skb_flow_get_ports(skb, nhoff, ip_proto, + data, hlen); + + return true; +} +EXPORT_SYMBOL(__skb_flow_dissect); + +static u32 hashrnd __read_mostly; +static __always_inline void __flow_hash_secret_init(void) +{ + net_get_random_once(&hashrnd, sizeof(hashrnd)); +} + +static __always_inline u32 __flow_hash_3words(u32 a, u32 b, u32 c) +{ + __flow_hash_secret_init(); + return jhash_3words(a, b, c, hashrnd); +} + +static inline u32 __flow_hash_from_keys(struct flow_keys *keys) +{ + u32 hash; + + /* get a consistent hash (same value on both flow directions) */ + if (((__force u32)keys->dst < (__force u32)keys->src) || + (((__force u32)keys->dst == (__force u32)keys->src) && + ((__force u16)keys->port16[1] < (__force u16)keys->port16[0]))) { + swap(keys->dst, keys->src); + swap(keys->port16[0], keys->port16[1]); + } + + hash = __flow_hash_3words((__force u32)keys->dst, + (__force u32)keys->src, + (__force u32)keys->ports); + if (!hash) + hash = 1; + + return hash; +} + +u32 flow_hash_from_keys(struct flow_keys *keys) +{ + return __flow_hash_from_keys(keys); +} +EXPORT_SYMBOL(flow_hash_from_keys); + +/* + * __skb_get_hash: calculate a flow hash based on src/dst addresses + * and src/dst port numbers. Sets hash in skb to non-zero hash value + * on success, zero indicates no valid hash. Also, sets l4_hash in skb + * if hash is a canonical 4-tuple hash over transport ports. + */ +void __skb_get_hash(struct sk_buff *skb) +{ + struct flow_keys keys; + + if (!skb_flow_dissect(skb, &keys)) + return; + + if (keys.ports) + skb->l4_hash = 1; + + skb->sw_hash = 1; + + skb->hash = __flow_hash_from_keys(&keys); +} +EXPORT_SYMBOL(__skb_get_hash); + +/* + * Returns a Tx hash based on the given packet descriptor a Tx queues' number + * to be used as a distribution range. + */ +u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb, + unsigned int num_tx_queues) +{ + u32 hash; + u16 qoffset = 0; + u16 qcount = num_tx_queues; + + if (skb_rx_queue_recorded(skb)) { + hash = skb_get_rx_queue(skb); + while (unlikely(hash >= num_tx_queues)) + hash -= num_tx_queues; + return hash; + } + + if (dev->num_tc) { + u8 tc = netdev_get_prio_tc_map(dev, skb->priority); + qoffset = dev->tc_to_txq[tc].offset; + qcount = dev->tc_to_txq[tc].count; + } + + return (u16) reciprocal_scale(skb_get_hash(skb), qcount) + qoffset; +} +EXPORT_SYMBOL(__skb_tx_hash); + +u32 __skb_get_poff(const struct sk_buff *skb, void *data, + const struct flow_keys *keys, int hlen) +{ + u32 poff = keys->thoff; + + switch (keys->ip_proto) { + case IPPROTO_TCP: { + /* access doff as u8 to avoid unaligned access */ + const u8 *doff; + u8 _doff; + + doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff), + data, hlen, &_doff); + if (!doff) + return poff; + + poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2); + break; + } + case IPPROTO_UDP: + case IPPROTO_UDPLITE: + poff += sizeof(struct udphdr); + break; + /* For the rest, we do not really care about header + * extensions at this point for now. + */ + case IPPROTO_ICMP: + poff += sizeof(struct icmphdr); + break; + case IPPROTO_ICMPV6: + poff += sizeof(struct icmp6hdr); + break; + case IPPROTO_IGMP: + poff += sizeof(struct igmphdr); + break; + case IPPROTO_DCCP: + poff += sizeof(struct dccp_hdr); + break; + case IPPROTO_SCTP: + poff += sizeof(struct sctphdr); + break; + } + + return poff; +} + +/* skb_get_poff() returns the offset to the payload as far as it could + * be dissected. The main user is currently BPF, so that we can dynamically + * truncate packets without needing to push actual payload to the user + * space and can analyze headers only, instead. + */ +u32 skb_get_poff(const struct sk_buff *skb) +{ + struct flow_keys keys; + + if (!skb_flow_dissect(skb, &keys)) + return 0; + + return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb)); +} + +static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb) +{ +#ifdef CONFIG_XPS + struct xps_dev_maps *dev_maps; + struct xps_map *map; + int queue_index = -1; + + rcu_read_lock(); + dev_maps = rcu_dereference(dev->xps_maps); + if (dev_maps) { + map = rcu_dereference( + dev_maps->cpu_map[skb->sender_cpu - 1]); + if (map) { + if (map->len == 1) + queue_index = map->queues[0]; + else + queue_index = map->queues[reciprocal_scale(skb_get_hash(skb), + map->len)]; + if (unlikely(queue_index >= dev->real_num_tx_queues)) + queue_index = -1; + } + } + rcu_read_unlock(); + + return queue_index; +#else + return -1; +#endif +} + +static u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb) +{ + struct sock *sk = skb->sk; + int queue_index = sk_tx_queue_get(sk); + + if (queue_index < 0 || skb->ooo_okay || + queue_index >= dev->real_num_tx_queues) { + int new_index = get_xps_queue(dev, skb); + if (new_index < 0) + new_index = skb_tx_hash(dev, skb); + + if (queue_index != new_index && sk && + rcu_access_pointer(sk->sk_dst_cache)) + sk_tx_queue_set(sk, new_index); + + queue_index = new_index; + } + + return queue_index; +} + +struct netdev_queue *netdev_pick_tx(struct net_device *dev, + struct sk_buff *skb, + void *accel_priv) +{ + int queue_index = 0; + +#ifdef CONFIG_XPS + if (skb->sender_cpu == 0) + skb->sender_cpu = raw_smp_processor_id() + 1; +#endif + + if (dev->real_num_tx_queues != 1) { + const struct net_device_ops *ops = dev->netdev_ops; + if (ops->ndo_select_queue) + queue_index = ops->ndo_select_queue(dev, skb, accel_priv, + __netdev_pick_tx); + else + queue_index = __netdev_pick_tx(dev, skb); + + if (!accel_priv) + queue_index = netdev_cap_txqueue(dev, queue_index); + } + + skb_set_queue_mapping(skb, queue_index); + return netdev_get_tx_queue(dev, queue_index); +} |