Re: [PATCH for-next 2/3] RDMA/erdma: Refactor the storage structure of MTT entries

[Leon Romanovsky <leon@kernel.org>]

On Thu, Aug 17, 2023 at 06:21:50PM +0800, Cheng Xu wrote:
> Currently our MTT only support inline mtt entries (0 level MTT) and
> indirect MTT entries (1 level mtt), which will limit the maximum length
> of MRs. In order to implement a multi-level MTT, we refactor the
> structure of MTT first.
> 
> Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
> ---
>  drivers/infiniband/hw/erdma/erdma_hw.h    |   4 +-
>  drivers/infiniband/hw/erdma/erdma_qp.c    |   2 +-
>  drivers/infiniband/hw/erdma/erdma_verbs.c | 214 +++++++++++++---------
>  drivers/infiniband/hw/erdma/erdma_verbs.h |  26 ++-
>  4 files changed, 152 insertions(+), 94 deletions(-)

<...>

> +/* Hierarchical storage structure for MTT entries */
> +struct erdma_mtt {
> +	u64 *buf;
> +	size_t size;
> +
> +	bool continuous;
> +	union {
> +		dma_addr_t buf_dma;
> +		struct {
> +			struct scatterlist *sglist;
> +			u32 nsg;
> +			u32 level;
> +		};
> +	};
> +
> +	struct erdma_mtt *low_level;

This variable is used in third patch only, but please don't resubmit yet.

Thanks