net/sfc: fix outer match in MAE backend

The current code doesn't use match on invalid outer rule ID
in action rules of non-encap. flows. This is wrong and must
be fixed. Do that and explain correct behaviour in the code.

Fixes: dadff137931c ("net/sfc: support encap flow items in transfer rules")
Cc: stable@dpdk.org
Signed-off-by: Ivan Malov <ivan.malov@oktetlabs.ru>
Reviewed-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Reviewed-by: Andy Moreton <amoreton@xilinx.com>

diff --git a/drivers/net/sfc/sfc_mae.c b/drivers/net/sfc/sfc_mae.c
index 2ea2d63..61e795d 100644 (file)
--- a/drivers/net/sfc/sfc_mae.c
+++ b/drivers/net/sfc/sfc_mae.c
@@ -1928,12 +1928,12 @@ sfc_mae_rule_process_outer(struct sfc_adapter *sa,
                           struct sfc_mae_outer_rule **rulep,
                           struct rte_flow_error *error)
 {
-       struct sfc_mae_outer_rule *rule;
+       efx_mae_rule_id_t invalid_rule_id = { .id = EFX_MAE_RSRC_ID_INVALID };
        int rc;
 
        if (ctx->encap_type == EFX_TUNNEL_PROTOCOL_NONE) {
                *rulep = NULL;
-               return 0;
+               goto no_or_id;
        }
 
        SFC_ASSERT(ctx->match_spec_outer != NULL);
@@ -1961,21 +1961,27 @@ sfc_mae_rule_process_outer(struct sfc_adapter *sa,
        /* The spec has now been tracked by the outer rule entry. */
        ctx->match_spec_outer = NULL;
 
+no_or_id:
        /*
-        * Depending on whether we reuse an existing outer rule or create a
-        * new one (see above), outer rule ID is either a valid value or
-        * EFX_MAE_RSRC_ID_INVALID. Set it in the action rule match
-        * specification (and the full mask, too) in order to have correct
-        * class comparisons of the new rule with existing ones.
-        * Also, action rule match specification will be validated shortly,
-        * and having the full mask set for outer rule ID indicates that we
-        * will use this field, and support for this field has to be checked.
+        * In MAE, lookup sequence comprises outer parse, outer rule lookup,
+        * inner parse (when some outer rule is hit) and action rule lookup.
+        * If the currently processed flow does not come with an outer rule,
+        * its action rule must be available only for packets which miss in
+        * outer rule table. Set OR_ID match field to 0xffffffff/0xffffffff
+        * in the action rule specification; this ensures correct behaviour.
+        *
+        * If, on the other hand, this flow does have an outer rule, its ID
+        * may be unknown at the moment (not yet allocated), but OR_ID mask
+        * has to be set to 0xffffffff anyway for correct class comparisons.
+        * When the outer rule has been allocated, this match field will be
+        * overridden by sfc_mae_outer_rule_enable() to use the right value.
         */
-       rule = *rulep;
        rc = efx_mae_match_spec_outer_rule_id_set(ctx->match_spec_action,
-                                                 &rule->fw_rsrc.rule_id);
+                                                 &invalid_rule_id);
        if (rc != 0) {
-               sfc_mae_outer_rule_del(sa, *rulep);
+               if (*rulep != NULL)
+                       sfc_mae_outer_rule_del(sa, *rulep);
+
                *rulep = NULL;
 
                return rte_flow_error_set(error, rc,