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Date: Tue, 30 Jan 2024 09:04:00 +0100
From: Christoph Hellwig <hch@lst.de>
To: Matthew Wilcox <willy@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>,
	Chandan Babu R <chandan.babu@oracle.com>,
	"Darrick J. Wong" <djwong@kernel.org>,
	Hugh Dickins <hughd@google.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-xfs@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH 07/20] shmem: document how to "persist" data when using
 shmem_*file_setup
Message-ID: <20240130080400.GA22621@lst.de>
References: <20240129143502.189370-1-hch@lst.de> <20240129143502.189370-8-hch@lst.de> <ZbiR1Jj0gwxAPVSA@casper.infradead.org>
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On Tue, Jan 30, 2024 at 06:06:12AM +0000, Matthew Wilcox wrote:
> On Mon, Jan 29, 2024 at 03:34:49PM +0100, Christoph Hellwig wrote:
> > Add a blurb that simply dirtying the folio will persist data for in-kernel
> > shmem files.  This is what most of the callers already do.
> > 
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > Reviewed-by: Darrick J. Wong <djwong@kernel.org>
> 
> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
> 
> I noticed today that drivers/gpu/drm/i915/gem/i915_gem_shmem.c is
> going to a lot of effort to call write_begin and write_end.  I'll
> take that out as part of the shmem conversion to buffered_write_ops.

I was planning to look into that, but I'll happily leave it to.
It also calls into ->writepage in a somewhat gross way.