Merge branch 'use-tc_cls_can_offload_and_chain0-throughout-the-drivers'

Jakub Kicinski says:

====================
use tc_cls_can_offload_and_chain0() throughout the drivers

This set makes all drivers use a new tc_cls_can_offload_and_chain0()
helper which will set extack in case TC hw offload flag is disabled.

I chose to keep the new helper which also looks at the chain but
renamed it more appropriately.  The rationale being that most drivers
don't accept chains other than 0 and since we have to pass extack
to the helper we can as well pass the entire struct tc_cls_common_offload
and perform the most common checks.

This code makes the assumption that type_data in the callback can
be interpreted as struct tc_cls_common_offload, i.e. the real offload
structure has common part as the first member.  This allows us to
make the check once for all classifier types if driver supports
more than one.

v1:
 - drop the type validation in nfp and netdevsim.
v2:
 - reorder checks in patch 1;
 - split other changes from patch 1;
 - add the i40e patch in;
 - add one more test case - for chain 0 extack.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 14 insertions, 0 deletions

diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h
index fa2f6fb14093..87406252f0a3 100644
--- a/include/net/pkt_cls.h
+++ b/include/net/pkt_cls.h
@@ -656,6 +656,20 @@ static inline bool tc_can_offload_extack(const struct net_device *dev,
 	return can;
 }
 
+static inline bool
+tc_cls_can_offload_and_chain0(const struct net_device *dev,
+			      struct tc_cls_common_offload *common)
+{
+	if (!tc_can_offload_extack(dev, common->extack))
+		return false;
+	if (common->chain_index) {
+		NL_SET_ERR_MSG(common->extack,
+			       "Driver supports only offload of chain 0");
+		return false;
+	}
+	return true;
+}
+
 static inline bool tc_skip_hw(u32 flags)
 {
 	return (flags & TCA_CLS_FLAGS_SKIP_HW) ? true : false;