Policer was not dumping or updating timestamps

Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

On devices that support TC U32 offloads, this flag enables a filter to be
added only to HW. skip-sw and skip-hw are mutually exclusive flags. By
default without any flags, the filter is added to both HW and SW, but no
error checks are done in case of failure to add to HW. With skip-sw,
failure to add to HW is treated as an error.

Here is a sample script that adds 2 filters, one with skip-sw and the other
with skip-hw flag.

   # add ingress qdisc
   tc qdisc add dev p4p1 ingress

   # enable hw tc offload.
   ethtool -K p4p1 hw-tc-offload on

   # add u32 filter with skip-sw flag.
   tc filter add dev p4p1 parent ffff: protocol ip prio 99 \
      handle 800:0:1 u32 ht 800: flowid 800:1 \
      skip-sw \
      match ip src 192.168.1.0/24 \
      action drop

   # add u32 filter with skip-hw flag.
   tc filter add dev p4p1 parent ffff: protocol ip prio 99 \
      handle 800:0:2 u32 ht 800: flowid 800:2 \
      skip-hw \
      match ip src 192.168.2.0/24 \
      action drop

Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch is based on a patch made by John Fastabend.
It adds support for offloading cls_flower.
when NETIF_F_HW_TC is on:
  flags = 0       => Rule will be processed twice - by hardware, and if
                     still relevant, by software.
  flags = SKIP_HW => Rull will be processed by software only

If hardware fail/not capabale to apply the rule, operation will NOT
fail. Filter will be processed by SW only.

Acked-by: Jiri Pirko <jiri@mellanox.com>
Suggested-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Amir Vadai <amir@vadai.me>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the initial implementation the only way to stop a rule from being
inserted into the hardware table was via the device feature flag.
However this doesn't work well when working on an end host system
where packets are expect to hit both the hardware and software
datapaths.

For example we can imagine a rule that will match an IP address and
increment a field. If we install this rule in both hardware and
software we may increment the field twice. To date we have only
added support for the drop action so we have been able to ignore
these cases. But as we extend the action support we will hit this
example plus more such cases. Arguably these are not even corner
cases in many working systems these cases will be common.

To avoid forcing the driver to always abort (i.e. the above example)
this patch adds a flag to add a rule in software only. A careful
user can use this flag to build software and hardware datapaths
that work together. One example we have found particularly useful
is to use hardware resources to set the skb->mark on the skb when
the match may be expensive to run in software but a mark lookup
in a hash table is cheap. The idea here is hardware can do in one
lookup what the u32 classifier may need to traverse multiple lists
and hash tables to compute. The flag is only passed down on inserts.
On deletion to avoid stale references in hardware we always try
to remove a rule if it exists.

The flags field is part of the classifier specific options. Although
it is tempting to lift this into the generic structure doing this
proves difficult do to how the tc netlink attributes are implemented
along with how the dump/change routines are called. There is also
precedence for putting seemingly generic pieces in the specific
classifier options such as TCA_U32_POLICE, TCA_U32_ACT, etc. So
although not ideal I've left FLAGS in the u32 options as well as it
simplifies the code greatly and user space has already learned how
to manage these bits ala 'tc' tool.

Another thing if trying to update a rule we require the flags to
be unchanged. This is to force user space, software u32 and
the hardware u32 to keep in sync. Thanks to Simon Horman for
catching this case.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Existing bpf_clone_redirect() helper clones skb before redirecting
it to RX or TX of destination netdev.
Introduce bpf_redirect() helper that does that without cloning.

Benchmarked with two hosts using 10G ixgbe NICs.
One host is doing line rate pktgen.
Another host is configured as:
$ tc qdisc add dev $dev ingress
$ tc filter add dev $dev root pref 10 u32 match u32 0 0 flowid 1:2 \
   action bpf run object-file tcbpf1_kern.o section clone_redirect_xmit drop
so it receives the packet on $dev and immediately xmits it on $dev + 1
The section 'clone_redirect_xmit' in tcbpf1_kern.o file has the program
that does bpf_clone_redirect() and performance is 2.0 Mpps

$ tc filter add dev $dev root pref 10 u32 match u32 0 0 flowid 1:2 \
   action bpf run object-file tcbpf1_kern.o section redirect_xmit drop
which is using bpf_redirect() - 2.4 Mpps

and using cls_bpf with integrated actions as:
$ tc filter add dev $dev root pref 10 \
  bpf run object-file tcbpf1_kern.o section redirect_xmit integ_act classid 1
performance is 2.5 Mpps

To summarize:
u32+act_bpf using clone_redirect - 2.0 Mpps
u32+act_bpf using redirect - 2.4 Mpps
cls_bpf using redirect - 2.5 Mpps

For comparison linux bridge in this setup is doing 2.1 Mpps
and ixgbe rx + drop in ip_rcv - 7.8 Mpps

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Often cls_bpf classifier is used with single action drop attached.
Optimize this use case and let cls_bpf return both classid and action.
For backwards compatibility reasons enable this feature under
TCA_BPF_FLAG_ACT_DIRECT flag.

Then more interesting programs like the following are easier to write:
int cls_bpf_prog(struct __sk_buff *skb)
{
  /* classify arp, ip, ipv6 into different traffic classes
   * and drop all other packets
   */
  switch (skb->protocol) {
  case htons(ETH_P_ARP):
    skb->tc_classid = 1;
    break;
  case htons(ETH_P_IP):
    skb->tc_classid = 2;
    break;
  case htons(ETH_P_IPV6):
    skb->tc_classid = 3;
    break;
  default:
    return TC_ACT_SHOT;
  }

  return TC_ACT_OK;
}

Joint work with Daniel Borkmann.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Jamal points out that this header also contains kernel internal magic that
cannot be used from userspace for anything meaningful.

Lets remove what the kernel doesn't use anymore and wrap remainder with
__KERNEL__.

Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

This patch introduces a flow-based filter. So far, the very essential
packet fields are supported.

This patch is only the first step. There is a lot of potential performance
improvements possible to implement. Also a lot of features are missing
now. They will be addressed in follow-up patches.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>