1 Commits

Author	SHA1	Message	Date
Tatyana Nikolova	30dc5e63d6	RDMA/core: Add support for iWARP Port Mapper user space service ... This patch adds iWARP Port Mapper (IWPM) Version 2 support. The iWARP Port Mapper implementation is based on the port mapper specification section in the Sockets Direct Protocol paper - http://www.rdmaconsortium.org/home/draft-pinkerton-iwarp-sdp-v1.0.pdf Existing iWARP RDMA providers use the same IP address as the native TCP/IP stack when creating RDMA connections. They need a mechanism to claim the TCP ports used for RDMA connections to prevent TCP port collisions when other host applications use TCP ports. The iWARP Port Mapper provides a standard mechanism to accomplish this. Without this service it is possible for RDMA application to bind/listen on the same port which is already being used by native TCP host application. If that happens the incoming TCP connection data can be passed to the RDMA stack with error. The iWARP Port Mapper solution doesn't contain any changes to the existing network stack in the kernel space. All the changes are contained with the infiniband tree and also in user space. The iWARP Port Mapper service is implemented as a user space daemon process. Source for the IWPM service is located at http://git.openfabrics.org/git?p=~tnikolova/libiwpm-1.0.0/.git;a=summary The iWARP driver (port mapper client) sends to the IWPM service the local IP address and TCP port it has received from the RDMA application, when starting a connection. The IWPM service performs a socket bind from user space to get an available TCP port, called a mapped port, and communicates it back to the client. In that sense, the IWPM service is used to map the TCP port, which the RDMA application uses to any port available from the host TCP port space. The mapped ports are used in iWARP RDMA connections to avoid collisions with native TCP stack which is aware that these ports are taken. When an RDMA connection using a mapped port is terminated, the client notifies the IWPM service, which then releases the TCP port. The message exchange between the IWPM service and the iWARP drivers (between user space and kernel space) is implemented using netlink sockets. 1) Netlink interface functions are added: ibnl_unicast() and ibnl_mulitcast() for sending netlink messages to user space 2) The signature of the existing ibnl_put_msg() is changed to be more generic 3) Two netlink clients are added: RDMA_NL_NES, RDMA_NL_C4IW corresponding to the two iWarp drivers - nes and cxgb4 which use the IWPM service 4) Enums are added to enumerate the attributes in the netlink messages, which are exchanged between the user space IWPM service and the iWARP drivers Signed-off-by: Tatyana Nikolova <tatyana.e.nikolova@intel.com> Signed-off-by: Steve Wise <swise@opengridcomputing.com> Reviewed-by: PJ Waskiewicz <pj.waskiewicz@solidfire.com> [ Fold in range checking fixes and nlh_next removal as suggested by Dan Carpenter and Steve Wise. Fix sparse endianness in hash. - Roland ] Signed-off-by: Roland Dreier <roland@purestorage.com>	2014-06-10 10:11:45 -07:00