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Date:   Thu, 26 Mar 2020 07:45:56 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     "Martin K. Petersen" <martin.petersen@oracle.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
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Subject: Re: [PATCH v7 0/6] block: Introduce REQ_ALLOCATE flag for
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On Thu, Mar 26, 2020 at 10:34:42AM -0400, Martin K. Petersen wrote:
> I just worry about the proliferation of identical merging and splitting
> code throughout the block stack as we add additional single-range, no
> payload operations (Verify, etc.). I prefer to enforce the semantics in
> the LLD and not in the plumbing. But I won't object to a separate
> REQ_OP_ALLOCATE if you find the resulting code duplication acceptable.

I find it acceptable for now.  And I think we should find some way
(e.g. by being table driven) to share code between differnet opcodes.