datapath: Rename last_action() as nla_is_last() and move to netlink.h

The original motivation for this change was to allow the helper to be used
in files other than actions.c as part of work on an odp select group
action.

It was as pointed out by Thomas Graf that this helper would be best off
living in netlink.h. Furthermore, I think that the generic nature of this
helper means it is best off in netlink.h regardless of if it is used more
than one .c file or not. Thus, I would like it considered independent of
the work on an odp select group action.

Cc: Thomas Graf <tgraf@suug.ch>
Cc: Pravin Shelar <pshelar@nicira.com>
Cc: Andy Zhou <azhou@nicira.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Acked-by: Thomas Graf <tgraf@noironetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/net/netlink.h b/include/net/netlink.h
index 7b903e1bdbbb..64158353ecb2 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -1185,4 +1185,14 @@ static inline int nla_validate_nested(const struct nlattr *start, int maxtype,
 #define nla_for_each_nested(pos, nla, rem) \
 	nla_for_each_attr(pos, nla_data(nla), nla_len(nla), rem)
 
+/**
+ * nla_is_last - Test if attribute is last in stream
+ * @nla: attribute to test
+ * @rem: bytes remaining in stream
+ */
+static inline bool nla_is_last(const struct nlattr *nla, int rem)
+{
+	return nla->nla_len == rem;
+}
+
 #endif