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	id 82B8868AFE; Wed, 29 May 2024 07:21:14 +0200 (CEST)
Date: Wed, 29 May 2024 07:21:14 +0200
From: Christoph Hellwig <hch@lst.de>
To: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: Christoph Hellwig <hch@lst.de>, linux-fsdevel@vger.kernel.org,
	linux-ext4@vger.kernel.org
Subject: Re: [PATCH 1/7] fs: Introduce buffered_write_operations
Message-ID: <20240529052114.GB15312@lst.de>
References: <20240528164829.2105447-1-willy@infradead.org> <20240528164829.2105447-2-willy@infradead.org>
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On Tue, May 28, 2024 at 05:48:22PM +0100, Matthew Wilcox (Oracle) wrote:
> Start the process of moving write_begin and write_end out from the
> address_space_operations to their own struct.
> 
> The new write_begin returns the folio or an ERR_PTR instead of returning
> the folio by reference.  It also accepts len as a size_t and (as
> documented) the len may be larger than PAGE_SIZE.
> 
> Pass an optional buffered_write_operations pointer to various functions
> in filemap.c.  The old names are available as macros for now, except
> for generic_file_write_iter() which is used as a function pointer by
> many filesystems.  If using the new functions, the filesystem can have
> per-operation fsdata instead of per-page fsdata.

The model looks good, but buffered_write_operations sounds a little
too generic for a helper that hopefully won't have too many users in
the end.