net/enic: ignore VLAN inner type when it is zero

When a VLAN pattern is present, the flow handler always copies its
inner_type to the match buffer regardless of its value (i.e. HW
matches inner_type against packet's inner ethertype). When inner_type
spec and mask are both 0, adding it to the match buffer is usually
harmless but breaks the following pattern used in some applications
like OVS-DPDK.

flow create 0 ingress ... pattern eth ... type is 0x0800 /
vlan tci spec 0x2 tci mask 0xefff / ipv4 / end actions count /
of_pop_vlan / ...

The VLAN pattern's inner_type is 0. And the outer eth pattern's type
actually specifies the inner ethertype. The outer ethertype (0x0800)
is first copied to the match buffer. Then, the driver copies
inner_type (0) to the match buffer, which overwrites the existing
0x0800 with 0 and breaks the app usage above.

Simply ignore inner_type when it is 0, which is the correct
behavior. As a byproduct, the driver can support the usage like the
above.

Fixes: ea7768b5bba8 ("net/enic: add flow implementation based on Flow Manager API")
Cc: stable@dpdk.org
Signed-off-by: Hyong Youb Kim <hyonkim@cisco.com>
Reviewed-by: John Daley <johndale@cisco.com>

diff --git a/drivers/net/enic/enic_fm_flow.c b/drivers/net/enic/enic_fm_flow.c
index ee671e1..94e39a9 100644 (file)
--- a/drivers/net/enic/enic_fm_flow.c
+++ b/drivers/net/enic/enic_fm_flow.c
@@ -392,8 +392,11 @@ enic_fm_copy_item_vlan(struct copy_item_args *arg)
        eth_mask = (void *)&fm_mask->l2.eth;
        eth_val = (void *)&fm_data->l2.eth;
 
-       /* Outer TPID cannot be matched */
-       if (eth_mask->ether_type)
+       /*
+        * Outer TPID cannot be matched. If inner_type is 0, use what is
+        * in the eth header.
+        */
+       if (eth_mask->ether_type && mask->inner_type)
                return -ENOTSUP;
 
        /*
@@ -401,8 +404,10 @@ enic_fm_copy_item_vlan(struct copy_item_args *arg)
         * L2, regardless of vlan stripping settings. So, the inner type
         * from vlan becomes the ether type of the eth header.
         */
-       eth_mask->ether_type = mask->inner_type;
-       eth_val->ether_type = spec->inner_type;
+       if (mask->inner_type) {
+               eth_mask->ether_type = mask->inner_type;
+               eth_val->ether_type = spec->inner_type;
+       }
        fm_data->fk_header_select |= FKH_ETHER | FKH_QTAG;
        fm_mask->fk_header_select |= FKH_ETHER | FKH_QTAG;
        fm_data->fk_vlan = rte_be_to_cpu_16(spec->tci);