Re: [PATCH rdma-next] RDMA: Allow ib_client's to fail when add() is called

[Jason Gunthorpe <jgg@ziepe.ca>]

On Tue, Apr 21, 2020 at 08:24:40PM +0300, Leon Romanovsky wrote:
> From: Jason Gunthorpe <jgg@mellanox.com>
> 
> When a client is added it isn't allowed to fail, but all the client's have
> various failure paths within their add routines.
> 
> This creates the very fringe condition where the client was added, failed
> during add and didn't set the client_data. The core code will then still
> call other client_data centric ops like remove(), rename(), get_nl_info(),
> and get_net_dev_by_params() with NULL client_data - which is confusing and
> unexpected.
> 
> If the add() callback fails, then do not call any more client ops for the
> device, even remove.
> 
> Remove all the now redundant checks for NULL client_data in ops callbacks.
> 
> Update all the add() callbacks to return error codes
> appropriately. EOPNOTSUPP is used for cases where the ULP does not support
> the ib_device - eg because it only works with IB.
> 
> Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
> Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
> Acked-by: Ursula Braun <ubraun@linux.ibm.com>
> ---
>  drivers/infiniband/core/cm.c                  | 24 ++++++++++--------
>  drivers/infiniband/core/cma.c                 | 23 +++++++++--------
>  drivers/infiniband/core/device.c              | 16 ++++++++++--
>  drivers/infiniband/core/mad.c                 | 17 ++++++++++---
>  drivers/infiniband/core/multicast.c           | 12 ++++-----
>  drivers/infiniband/core/sa_query.c            | 22 ++++++++--------
>  drivers/infiniband/core/user_mad.c            | 22 ++++++++--------
>  drivers/infiniband/core/uverbs_main.c         | 24 +++++++++---------
>  drivers/infiniband/ulp/ipoib/ipoib_main.c     | 15 ++++-------
>  .../infiniband/ulp/opa_vnic/opa_vnic_vema.c   | 12 ++++-----
>  drivers/infiniband/ulp/srp/ib_srp.c           | 21 ++++++++--------
>  drivers/infiniband/ulp/srpt/ib_srpt.c         | 25 ++++++++-----------
>  include/rdma/ib_verbs.h                       |  2 +-
>  net/rds/ib.c                                  | 21 ++++++++++------
>  net/smc/smc_ib.c                              | 10 +++-----
>  15 files changed, 142 insertions(+), 124 deletions(-)

Applied to for-next

Jason