>I am still not sure to follow you. My basic thought was that unmapped >multicast addresses are MGIDs specified by the application such that >rdma-cm doesn't treat them as IPv6 multicast address and no mapping is >applied on them.
This is basically correct, but the MGIDs must be of the format 0xFF1-scope-A01B. The kernel keys off this in the address to determine if the mapping should be made. >1. "if SA receives a request to create a multicast group with the MGID >undefined" >2. "the MGID that it creates shall be of the following format" > >so there are two parts here, 1st request the SA to create a new group, >assign it an MGID (what about joining this node/port to the group), 2nd, >getting back the MGID created by the SA. Looking on the rdma-cm kernel >code, I don't see where/how it specifies to the SA that the MGID is >undefined? shouldn't it not set the MGID bit in the component mask in >this case? next, I don't see where the MGID created by the SA is given >From 15.2.5.17.2: "MGID undefined" means either the MGID bit in the component mask is not set, or if the MGID bit in the component mask is set, the MGID component of MCMemberRecord:MGID is 0. If the join request is for an address of 0, then the MGID will be 0 in the SA join request. The SA will assign an MGID starting with 0xFF1-scope-A01B. When the join request completes, the MCMemberRecord information is given to the user as part of the multicast join event in the form of address handle attributes. (See cma_ib_mc_handler.) What's missing is Jason's patch to fix the IPv6 mapping, and a way to extend the rdma_cm to support the full range of unmapped addresses. I just haven't been able to get to either of these yet. - Sean -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
