IB/core: Support for CMA multicast join flags

Added UCMA and CMA support for multicast join flags. Flags are
passed using UCMA CM join command previously reserved fields.
Currently supporting two join flags indicating two different
multicast JoinStates:

1. Full Member:
   The initiator creates the Multicast group(MCG) if it wasn't
   previously created, can send Multicast messages to the group
   and receive messages from the MCG.

2. Send Only Full Member:
   The initiator creates the Multicast group(MCG) if it wasn't
   previously created, can send Multicast messages to the group
   but doesn't receive any messages from the MCG.

   IB: Send Only Full Member requires a query of ClassPortInfo
       to determine if SM/SA supports this option. If SM/SA
       doesn't support Send-Only there will be no join request
       sent and an error will be returned.

   ETH: When Send Only Full Member is requested no IGMP join
	will be sent.

Signed-off-by: Alex Vesker <valex@mellanox.com>
Reviewed by: Hal Rosenstock <hal@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/include/uapi/rdma/rdma_user_cm.h b/include/uapi/rdma/rdma_user_cm.h
index 3066718eb120..01923d463673 100644
--- a/include/uapi/rdma/rdma_user_cm.h
+++ b/include/uapi/rdma/rdma_user_cm.h
@@ -244,12 +244,19 @@ struct rdma_ucm_join_ip_mcast {
 	__u32 id;
 };
 
+/* Multicast join flags */
+enum {
+	RDMA_MC_JOIN_FLAG_FULLMEMBER,
+	RDMA_MC_JOIN_FLAG_SENDONLY_FULLMEMBER,
+	RDMA_MC_JOIN_FLAG_RESERVED,
+};
+
 struct rdma_ucm_join_mcast {
 	__u64 response;		/* rdma_ucma_create_id_resp */
 	__u64 uid;
 	__u32 id;
 	__u16 addr_size;
-	__u16 reserved;
+	__u16 join_flags;
 	struct sockaddr_storage addr;
 };