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Date: Tue, 24 Sep 2024 07:36:44 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Anuj Gupta <anuj20.g@samsung.com>, Christoph Hellwig <hch@lst.de>,
	Kanchan Joshi <joshi.k@samsung.com>, linux-block@vger.kernel.org,
	linux-scsi@vger.kernel.org, linux-nvme@lists.infradead.org
Subject: Re: fine-grained PI control
Message-ID: <20240924053644.GA10569@lst.de>
References: <20240705083205.2111277-1-hch@lst.de> <yq1ttgz5l6d.fsf@ca-mkp.ca.oracle.com> <CGME20240918064651epcas5p418d61389752da25e5fc50e6a50a111b8@epcas5p4.samsung.com> <20240918063910.hqntgm5jy2jisys2@green245> <yq1bk0dhlko.fsf@ca-mkp.ca.oracle.com>
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On Mon, Sep 23, 2024 at 09:59:10PM -0400, Martin K. Petersen wrote:
> Originally we had code in Linux allowing filesystems to attach
> additional metadata to bios which would then be stored in the app tag
> space. This was intended for backpointers but never really took off.
> However, if we move the burden of PI generation to filesystems as
> Christoph suggested, then we can revisit using the app tag space.

Just to make clear I want file systems to be able to opt into
generating PI, not get rid of the auto generation.  That is actually
kinda possible already, I just want to make it nicer.