IB/uverbs: Add support to extend flow steering specifications

Flow steering specifications structures were implemented as in an
extensible way that allows one to add new filters and new fields
to existing filters.
These specifications have never been extended, therefore the
kernel flow specifications size and the user flow specifications size
were must to be equal.

In downstream patch, the IPv4 flow specifications type is extended to
support TOS and TTL fields.

To support an extension we change the flow specifications size
condition test to be as following:

* If the user flow specifications is bigger than the kernel
specifications, we verify that all the bits which not in the kernel
specifications are zeros and the flow is added only with the kernel
specifications fields.

* Otherwise, we add flow rule only with the user specifications fields.

User space filters must be aligned with 32bits.

Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 10 insertions, 0 deletions

diff --git a/include/rdma/ib_verbs.h b/include/rdma/ib_verbs.h
index d74c76bf76d3..4570d8844f63 100644
--- a/include/rdma/ib_verbs.h
+++ b/include/rdma/ib_verbs.h
@@ -1623,6 +1623,8 @@ struct ib_flow_eth_filter {
         u8      src_mac[6];
         __be16  ether_type;
         __be16  vlan_tag;
+        /* Must be last */
+        u8      real_sz[0];
 };
 
 struct ib_flow_spec_eth {
@@ -1635,6 +1637,8 @@ struct ib_flow_spec_eth {
 struct ib_flow_ib_filter {
         __be16 dlid;
         __u8   sl;
+        /* Must be last */
+        u8      real_sz[0];
 };
 
 struct ib_flow_spec_ib {
@@ -1647,6 +1651,8 @@ struct ib_flow_spec_ib {
 struct ib_flow_ipv4_filter {
         __be32  src_ip;
         __be32  dst_ip;
+        /* Must be last */
+        u8      real_sz[0];
 };
 
 struct ib_flow_spec_ipv4 {
@@ -1659,6 +1665,8 @@ struct ib_flow_spec_ipv4 {
 struct ib_flow_ipv6_filter {
         u8      src_ip[16];
         u8      dst_ip[16];
+        /* Must be last */
+        u8      real_sz[0];
 };
 
 struct ib_flow_spec_ipv6 {
@@ -1671,6 +1679,8 @@ struct ib_flow_spec_ipv6 {
 struct ib_flow_tcp_udp_filter {
         __be16  dst_port;
         __be16  src_port;
+        /* Must be last */
+        u8      real_sz[0];
 };
 
 struct ib_flow_spec_tcp_udp {