NAME

       rxe - Software RDMA over Ethernet

SYNOPSIS

       modprobe rdma_rxe
       This is usually performed by a configuration utility (see rxe_cfg(8).)

DESCRIPTION

       The rdma_rxe kernel module provides a software implementation of the RoCEv2 protocol. The RoCEv2 protocol
       is an RDMA transport protocol that exists on top of  UDP/IPv4  or  UDP/IPv6.  The  InfiniBand  (IB)  Base
       Transport Header (BTH) is encapsulated in the UDP packet.

       Once  a  RXE  instance  has been created, communicating via RXE is the same as communicating via any OFED
       compatible Infiniband HCA, albeit in some cases with addressing implications.

       In particular, while the use of a GRH header is optional within IB subnets, it is  mandatory  with  RoCE.
       Verbs  applications  written  over  IB verbs should work seamlessly, but they require provisioning of GRH
       information when creating address vectors. The library and driver are modified  to  provide  for  mapping
       from GID to MAC addresses required by the hardware.

FILES

       /sys/class/infiniband/rxe[0,1,...]
              Directory that holds RDMA device information. The format is the same as other RDMA devices.

       /sys/module/rdma_rxe_net/parameters/add
              Write only file used by rxe_cfg(8) to add new RXE devices to existing Ethernet devices.

       /sys/module/rdma_rxe_net/parameters/remove
              Write only file used by rxe_cfg(8) to remove RXE devices.

       /sys/module/rdma_rxe_net/parameters/mtu
              Write only file used by rxe_cfg(8) to configure RoCE and Ethernet MTU values.

       /sys/module/rdma_rxe/parameters/max_ucontext
              Read/Write file that sets a limit on the number of UCs allowed per RXE device.

       /sys/module/rdma_rxe/parameters/max_qp
              Read/Write file that sets a limit on the number of QPs allowed per RXE device.

       /sys/module/rdma_rxe/parameters/max_qp_wr
              Read/Write file that sets a limit on the number of WRs per QP allowed per RXE device.

       /sys/module/rdma_rxe/parameters/max_mr
              Read/Write file that sets a limit on the number of MRs allowed per RXE device.

       /sys/module/rdma_rxe/parameters/max_fmr
              Read/Write file that sets a limit on the number of FMRs allowed per RXE device.

       /sys/module/rdma_rxe/parameters/max_cq
              Read/Write file that sets a limit on the number of CQs allowed per RXE device.

       /sys/module/rdma_rxe/parameters/max_log_cqe
              Read/Write  file  that sets a limit on the log base 2 of the number of CQEs per CQ allowed per RXE
              device.

       /sys/module/rdma_rxe/parameters/max_inline_data
              Read/Write file that sets a limit on the maximum amount of inline data  per  WR  allowed  per  RXE
              device.

              The  above  configuration  parameters  only  affect  a  new  RXE  instance  when it is created not
              afterwards.

       /sys/module/rdma_rxe/parameters/crc_disable
              Read/Write file that controls the disabling of ICRC computation. Set to a nonzero value for  TRUE.
              Zero for FALSE.

       /sys/module/rdma_rxe/parameters/fast_comp|req|resp|arb
              Read/Write file that enables calling kernel tasklets as subroutines to reduce latency.

       /sys/module/rdma_rxe/parameters/nsec_per_packet|kbyte
              Read/Write  file that controls static rate pacing for output packets. If set to nonzero values the
              minimum delay to the next packet is set to nsec_per_kbyte * sizeof(current packet  in  KBytes)  or
              nsec_per_packet which ever is less.

       /sys/module/rdma_rxe/parameters/max_packet_per_ack
              Read/Write  file  that controls the issuing of acks by the responder during a long message. If set
              additional acks will be generated every max_pkt_per_ack packets.

       /sys/module/rdma_rxe/parameters/max_skb_per_qp
              Read/Write file that controls the number of skbs (packets) that a requester can queue for  sending
              internally.

       /sys/module/rdma_rxe/parameters/max_req_comp_gap
              Read/Write  file  that  controls  the  maximum gap between the PSN of request packets send and ack
              packets received.

       /sys/module/rdma_rxe/parameters/default_mtu
              Read/Write file that controls the default mtu used for UD packets.

SEE ALSO

       rxe_cfg(8), verbs(7),

AUTHORS

       Written by John Groves, Frank Zago and Bob Pearson at System Fabric Works.