Re: [PATCH for-next v6 0/6] Replace AV by AH in UD sends

[Jason Gunthorpe <jgg@nvidia.com>]

On Thu, Oct 07, 2021 at 03:40:46PM -0500, Bob Pearson wrote:
> Currently the rdma_rxe driver and its user space provider exchange
> addressing information for UD sends by having the provider compute an
> address vector (AV) and send it with each WQE. This is not the way
> that the RDMA verbs API was intended to operate.
> 
> This series of patches modifies the way UD send WQEs work by exchanging
> an index identifying the AH replacing the 88 byte AV by a 4 byte AH
> index. In order to not break compatibility with the existing API the
> rdma_rxe driver will recognise when an older version of the provider
> is not sending an index (i.e. it is 0) and will use the AV instead.
> 
> This series of patches is rebased to
>     commit: 286dba65a4a65a6d5de011767061f6ffa6e10389 (for-next)
> 
> v6:
>   Rebase to 5.15.0-rc4
>   Reduced the max number of AH objects from 1M to 32K.
> 
> v5:
>   Rebase to 5.15.0-rc2+
> 
> v4:
>   Rebase to 5.15.0-rc1+
> 
> v3:
>   Split up commits into smaller steps.
> 
> v2:
>   Rearranged AV in rxe_send_wqe to be in the ud struct but padded to the
>   same offset as the original preserving ABI compatibility.
> 
> Bob Pearson (6):
>   RDMA/rxe: Move AV from rxe_send_wqe to rxe_send_wr
>   RDMA/rxe: Change AH objects to indexed
>   RDMA/rxe: Create AH index and return to user space
>   RDMA/rxe: Replace ah->pd by ah->ibah.pd
>   RDMA/rxe: Lookup kernel AH from ah index in UD WQEs
>   RDMA/rxe: Convert kernel UD post send to use ah_num

Applied to for-next, thanks

Jason