net: ptp: do not reimplement PTP/BPF classifier

There are currently pch_gbe, cpts, and ixp4xx_eth drivers that open-code
and reimplement a BPF classifier for the PTP protocol. Since all of them
effectively do the very same thing and load the very same PTP/BPF filter,
we can just consolidate that code by introducing ptp_classify_raw() in
the time-stamping core framework which can be used in drivers.

As drivers get initialized after bootstrapping the core networking
subsystem, they can make use of ptp_insns wrapped through
ptp_classify_raw(), which allows to simplify and remove PTP classifier
setup code in drivers.

Joint work with Alexei Starovoitov.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Cc: Richard Cochran <richard.cochran@omicron.at>
Cc: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 7 insertions, 1 deletions

diff --git a/net/core/timestamping.c b/net/core/timestamping.c
index e43d56acf803..9ff26b3cc021 100644
--- a/net/core/timestamping.c
+++ b/net/core/timestamping.c
@@ -25,11 +25,17 @@
 
 static struct sk_filter *ptp_insns __read_mostly;
 
+unsigned int ptp_classify_raw(const struct sk_buff *skb)
+{
+        return SK_RUN_FILTER(ptp_insns, skb);
+}
+EXPORT_SYMBOL_GPL(ptp_classify_raw);
+
 static unsigned int classify(const struct sk_buff *skb)
 {
         if (likely(skb->dev && skb->dev->phydev &&
                    skb->dev->phydev->drv))
-                return SK_RUN_FILTER(ptp_insns, skb);
+                return ptp_classify_raw(skb);
         else
                 return PTP_CLASS_NONE;
 }