RDMA/ucma: Allow user space to specify AF_IB when joining multicast

Allow user space applications to join multicast groups using MGIDs
directly.  MGIDs may be passed using AF_IB addresses.  Since the
current multicast join command only supports addresses as large as
sockaddr_in6, define a new structure for joining addresses specified
using sockaddr_ib.

Since AF_IB allows the user to specify the qkey when resolving a
remote UD QP address, when joining the multicast group use the qkey
value, if one has been assigned.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

1 files changed, 11 insertions, 1 deletions

diff --git a/include/uapi/rdma/rdma_user_cm.h b/include/uapi/rdma/rdma_user_cm.h
index 6d03f9c16f1e..99b80abf360a 100644
--- a/include/uapi/rdma/rdma_user_cm.h
+++ b/include/uapi/rdma/rdma_user_cm.h
@@ -64,7 +64,8 @@ enum {
         RDMA_USER_CM_CMD_MIGRATE_ID,
         RDMA_USER_CM_CMD_QUERY,
         RDMA_USER_CM_CMD_BIND,
-        RDMA_USER_CM_CMD_RESOLVE_ADDR
+        RDMA_USER_CM_CMD_RESOLVE_ADDR,
+        RDMA_USER_CM_CMD_JOIN_MCAST
 };
 
 /*
@@ -242,6 +243,15 @@ struct rdma_ucm_join_ip_mcast {
         __u32 id;
 };
 
+struct rdma_ucm_join_mcast {
+        __u64 response;         /* rdma_ucma_create_id_resp */
+        __u64 uid;
+        __u32 id;
+        __u16 addr_size;
+        __u16 reserved;
+        struct sockaddr_storage addr;
+};
+
 struct rdma_ucm_get_event {
         __u64 response;
 };