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Date: Wed, 23 Oct 2024 05:45:13 -0700
From: Christoph Hellwig <hch@infradead.org>
To: Keith Busch <kbusch@kernel.org>
Cc: Tokunori Ikegami <ikegami.t@gmail.com>, linux-nvme@lists.infradead.org,
	Max Gurtovoy <mgurtovoy@nvidia.com>,
	Israel Rukshin <israelr@nvidia.com>
Subject: Re: [PATCH v3] nvme: fix nvme_ns_has_pi() to check PI size if
 metadata size or below
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References: <20241022181132.19871-1-ikegami.t@gmail.com>
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Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org

On Tue, Oct 22, 2024 at 01:20:44PM -0600, Keith Busch wrote:
> On Wed, Oct 23, 2024 at 03:10:54AM +0900, Tokunori Ikegami wrote:
> > The PI is the first bytes or last bytes of the metadata.
> > So its size is not equal to the metadata size only but below also.
> 
> This is still wrong because the only users of this function are with
> respect to PRACT. If anything, you could change the name from "has_pi"
> to "supports_pract", or something like that.

It's also use in the NVME_NS_METADATA_SUPPORTED for fabrics.
Where fabrics really means RDMA with the Mellanox PI offload.  I don't
really know if that supports PI smaller than the metadata size offhand.