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Date: Tue, 23 Jun 2026 17:06:47 +0200
From: Christoph Hellwig <hch@lst.de>
To: Keith Busch <kbusch@meta.com>
Cc: linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
	dm-devel@lists.linux.dev, hch@lst.de, axboe@kernel.dk,
	brauner@kernel.org, djwong@kernel.org, viro@zeniv.linux.org.uk,
	Keith Busch <kbusch@kernel.org>
Subject: Re: [PATCHv2 5/6] zloop: set dma_alignment from the backing files
 for direct I/O
Message-ID: <20260623150647.GE13628@lst.de>
References: <20260622174241.2299563-1-kbusch@meta.com> <20260622174241.2299563-6-kbusch@meta.com>
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On Mon, Jun 22, 2026 at 10:42:40AM -0700, Keith Busch wrote:
>  {
>  	struct block_device *sb_bdev = zone->file->f_mapping->host->i_sb->s_bdev;
>  	struct kstat st;
> +	bool have_dioalign = !vfs_getattr(&zone->file->f_path, &st,
> +					  STATX_DIOALIGN, 0) &&
> +			     (st.result_mask & STATX_DIOALIGN);

This is getting a bit crazy for an assignment :)

Maybe refactor this along the lines of the loop.c code?

> +	/* Direct I/O hands the request's pages to the backing files unchanged. */

Overly long line.