IB/uverbs: Add support for flow tag

The struct ib_uverbs_flow_spec_action_tag associates a tag_id with the
flow defined by any number of other flow_spec entries which can reference
L2, L3, and L4 packet contents.

Use of ib_uverbs_flow_spec_action_tag allows the consumer to identify
the set of rules which where matched by
the packet by examining the tag_id in the CQE.

Signed-off-by: Moses Reuben <mosesr@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/uverbs.h

@@ -228,6 +228,7 @@ struct ib_uverbs_flow_spec {
 		struct ib_uverbs_flow_spec_ipv4    ipv4;
 		struct ib_uverbs_flow_spec_tcp_udp tcp_udp;
 		struct ib_uverbs_flow_spec_ipv6    ipv6;
+		struct ib_uverbs_flow_spec_action_tag	flow_tag;
 	};
 };
 

drivers/infiniband/core/uverbs_cmd.c

@@ -3143,6 +3143,25 @@ ssize_t ib_uverbs_detach_mcast(struct ib_uverbs_file *file,
 	return ret ? ret : in_len;
 }
 
+static int kern_spec_to_ib_spec_action(struct ib_uverbs_flow_spec *kern_spec,
+				       union ib_flow_spec *ib_spec)
+{
+	ib_spec->type = kern_spec->type;
+	switch (ib_spec->type) {
+	case IB_FLOW_SPEC_ACTION_TAG:
+		if (kern_spec->flow_tag.size !=
+		    sizeof(struct ib_uverbs_flow_spec_action_tag))
+			return -EINVAL;
+
+		ib_spec->flow_tag.size = sizeof(struct ib_flow_spec_action_tag);
+		ib_spec->flow_tag.tag_id = kern_spec->flow_tag.tag_id;
+		break;
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
 static size_t kern_spec_filter_sz(struct ib_uverbs_flow_spec_hdr *spec)
 {
 	/* Returns user space filter size, includes padding */
@@ -3167,8 +3186,8 @@ static ssize_t spec_filter_size(void *kern_spec_filter, u16 kern_filter_size,
 	return kern_filter_size;
 }
 
-static int kern_spec_to_ib_spec(struct ib_uverbs_flow_spec *kern_spec,
-				union ib_flow_spec *ib_spec)
+static int kern_spec_to_ib_spec_filter(struct ib_uverbs_flow_spec *kern_spec,
+				       union ib_flow_spec *ib_spec)
 {
 	ssize_t actual_filter_sz;
 	ssize_t kern_filter_sz;
@@ -3263,6 +3282,18 @@ static int kern_spec_to_ib_spec(struct ib_uverbs_flow_spec *kern_spec,
 	return 0;
 }
 
+static int kern_spec_to_ib_spec(struct ib_uverbs_flow_spec *kern_spec,
+				union ib_flow_spec *ib_spec)
+{
+	if (kern_spec->reserved)
+		return -EINVAL;
+
+	if (kern_spec->type >= IB_FLOW_SPEC_ACTION_TAG)
+		return kern_spec_to_ib_spec_action(kern_spec, ib_spec);
+	else
+		return kern_spec_to_ib_spec_filter(kern_spec, ib_spec);
+}
+
 int ib_uverbs_ex_create_wq(struct ib_uverbs_file *file,
 			   struct ib_device *ib_dev,
 			   struct ib_udata *ucore,

include/uapi/rdma/ib_user_verbs.h

@@ -929,6 +929,19 @@ struct ib_uverbs_flow_spec_ipv6 {
 	struct ib_uverbs_flow_ipv6_filter mask;
 };
 
+struct ib_uverbs_flow_spec_action_tag {
+	union {
+		struct ib_uverbs_flow_spec_hdr hdr;
+		struct {
+			__u32 type;
+			__u16 size;
+			__u16 reserved;
+		};
+	};
+	__u32			      tag_id;
+	__u32			      reserved1;
+};
+
 struct ib_uverbs_flow_tunnel_filter {
 	__be32 tunnel_id;
 };