datapath: Get packet metadata from userspace in odp_packet_cmd_execute().

Until now, the tun_id and in_port have been lost when a packet is sent from
the kernel to userspace and then back to the kernel.  I didn't think that
this was a problem, but recent behavior made me look closer and see that
it makes a difference if sFlow is turned on or if an
ODP_ATTR_ACTION_CONTROLLER action is present.  We could possibly kluge
around those, but for future-proofing it seems better to pass the packet
metadata from userspace to the kernel.  That is what this commit does.

This commit introduces a user-kernel protocol break.  We could avoid that,
if it is desirable, by making ODP_PACKET_ATTR_KEY optional for
ODP_PACKET_CMD_EXECUTE commands.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jesse Gross <jesse@nicira.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/dpif.h b/lib/dpif.h
index 8452349b..60e3cb48 100644
--- a/lib/dpif.h
+++ b/lib/dpif.h
@@ -148,8 +148,10 @@ bool dpif_flow_dump_next(struct dpif_flow_dump *,
                          const struct dpif_flow_stats **);
 int dpif_flow_dump_done(struct dpif_flow_dump *);
 
-int dpif_execute(struct dpif *, const struct nlattr *actions,
-                 size_t actions_len, const struct ofpbuf *);
+int dpif_execute(struct dpif *,
+                 const struct nlattr *key, size_t key_len,
+                 const struct nlattr *actions, size_t actions_len,
+                 const struct ofpbuf *);
 
 enum dpif_upcall_type {
     DPIF_UC_MISS,               /* Miss in flow table. */