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Date: Tue, 27 Jan 2026 06:42:35 +0100
From: Christoph Hellwig <hch@lst.de>
To: Chuck Lever <cel@kernel.org>
Cc: Leon Romanovsky <leon@kernel.org>, Christoph Hellwig <hch@lst.de>,
	Jason Gunthorpe <jgg@nvidia.com>, linux-rdma@vger.kernel.org,
	linux-nfs@vger.kernel.org, Chuck Lever <chuck.lever@oracle.com>
Subject: Re: [PATCH v4 3/5] RDMA/core: add MR support for bvec-based RDMA
 operations
Message-ID: <20260127054235.GB24998@lst.de>
References: <20260126181414.105062-1-cel@kernel.org> <20260126181414.105062-4-cel@kernel.org>
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> +		struct {
> +			struct rdma_rw_reg_ctx {
> +				struct ib_sge		sge;
> +				struct ib_rdma_wr	wr;
> +				struct ib_reg_wr	reg_wr;
> +				struct ib_send_wr	inv_wr;
> +				struct ib_mr		*mr;
> +			}			*ctx;
> +			struct sg_table		sgt;
> +		} reg;

I still don't understand why the sgt is not in
struct rdma_rw_reg_ctx.  Right now that is allocate a little bit
later than the sgt initialization and freed a tiny bit to early,
but that seems to be easy to fix.

Doing so would reduce the memory usage for the common non-registration
path, and significantly reduce the churn in the patch.