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Date: Thu, 28 Nov 2024 04:24:04 +0100
From: Christoph Hellwig <hch@lst.de>
To: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Bart Van Assche <bvanassche@acm.org>,
	Nitesh Shetty <nj.shetty@samsung.com>,
	Javier Gonzalez <javier.gonz@samsung.com>,
	Matthew Wilcox <willy@infradead.org>,
	Keith Busch <kbusch@kernel.org>, Christoph Hellwig <hch@lst.de>,
	Keith Busch <kbusch@meta.com>,
	"linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
	"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
	"linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
	"io-uring@vger.kernel.org" <io-uring@vger.kernel.org>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	"joshi.k@samsung.com" <joshi.k@samsung.com>
Subject: Re: [PATCHv10 0/9] write hints with nvme fdp, scsi streams
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On Wed, Nov 27, 2024 at 03:14:09PM -0500, Martin K. Petersen wrote:
> How do you copy a block range without offload? You perform a READ to
> read the data into memory. And once the READ completes, you do a WRITE
> of the data to the new location.

Yes.  I.e. this is code that makes this pattern very clearm and for
which I'd love to be able to use copy offload when available:

http://git.infradead.org/?p=users/hch/xfs.git;a=blob;f=fs/xfs/xfs_zone_gc.c;h=ed8aa08b3c18d50afe79326e697d83e09542a9b6;hb=refs/heads/xfs-zoned#l820