[RFC PATCH v2 0/2] RDMA/rxe: Add RDMA Atomic Write operation

[Xiao Yang <yangx.jy@fujitsu.com>]

The IB SPEC v1.5[1][2] defined new RDMA operations (Atomic Write and Flush).
This patchset makes SoftRoCE support new RDMA Atomic Write on RC service.

I add ibv_wr_rdma_atomic_write() and a rdma_atomic_write example on my
rdma-core repository[3].  You can verify the patchset by building and
running the rdma_atomic_write example.
server:
$ ./rdma_atomic_write_server -s [server_address] -p [port_number]
client:
$ ./rdma_atomic_write_client -s [server_address] -p [port_number]

[1]: https://www.infinibandta.org/ibta-specification/ # login required
[2]: https://www.infinibandta.org/wp-content/uploads/2021/08/IBTA-Overview-of-IBTA-Volume-1-Release-1.5-and-MPE-2021-08-17-Secure.pptx
[3]: https://github.com/yangx-jy/rdma-core/tree/new_api

BTW: This patchset also needs the following fix.
https://www.spinics.net/lists/linux-rdma/msg107838.html

V1->V2:
1) Set IB_OPCODE_RDMA_ATOMIC_WRITE to 0x1D
2) Add rdma.atomic_wr in struct rxe_send_wr and use it to pass the atomic write value
3) Use smp_store_release() to ensure that all prior operations have completed

Xiao Yang (2):
  RDMA/rxe: Rename send_atomic_ack() and atomic member of struct
    resp_res
  RDMA/rxe: Support RDMA Atomic Write operation

 drivers/infiniband/sw/rxe/rxe_comp.c   |  4 ++
 drivers/infiniband/sw/rxe/rxe_opcode.c | 18 +++++++++
 drivers/infiniband/sw/rxe/rxe_opcode.h |  3 ++
 drivers/infiniband/sw/rxe/rxe_qp.c     |  5 ++-
 drivers/infiniband/sw/rxe/rxe_req.c    | 11 +++++-
 drivers/infiniband/sw/rxe/rxe_resp.c   | 53 +++++++++++++++++++-------
 drivers/infiniband/sw/rxe/rxe_verbs.h  |  2 +-
 include/rdma/ib_pack.h                 |  2 +
 include/rdma/ib_verbs.h                |  2 +
 include/uapi/rdma/ib_user_verbs.h      |  2 +
 include/uapi/rdma/rdma_user_rxe.h      |  1 +
 11 files changed, 85 insertions(+), 18 deletions(-)

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2.23.0