Re: [PATCH v3 11/28] iomap: pass readpage operation to read path

[Andrey Albershteyn <aalbersh@redhat.com>]

On 2023-10-11 11:31:17, Darrick J. Wong wrote:
> On Fri, Oct 06, 2023 at 08:49:05PM +0200, Andrey Albershteyn wrote:
> > diff --git a/include/linux/iomap.h b/include/linux/iomap.h
> > index 96dd0acbba44..3565c449f3c9 100644
> > --- a/include/linux/iomap.h
> > +++ b/include/linux/iomap.h
> > @@ -262,8 +262,25 @@ int iomap_file_buffered_write_punch_delalloc(struct inode *inode,
> >  		struct iomap *iomap, loff_t pos, loff_t length, ssize_t written,
> >  		int (*punch)(struct inode *inode, loff_t pos, loff_t length));
> >  
> > -int iomap_read_folio(struct folio *folio, const struct iomap_ops *ops);
> > -void iomap_readahead(struct readahead_control *, const struct iomap_ops *ops);
> > +struct iomap_readpage_ops {
> > +	/*
> > +	 * Filesystems wishing to attach private information to a direct io bio
> > +	 * must provide a ->submit_io method that attaches the additional
> > +	 * information to the bio and changes the ->bi_end_io callback to a
> > +	 * custom function.  This function should, at a minimum, perform any
> > +	 * relevant post-processing of the bio and end with a call to
> > +	 * iomap_read_end_io.
> > +	 */
> > +	void (*submit_io)(const struct iomap_iter *iter, struct bio *bio,
> > +			loff_t file_offset);
> > +	struct bio_set *bio_set;
> 
> Needs a comment to mention that iomap will allocate bios from @bio_set
> if non-null; or its own internal bioset if null.

Sure.

> > +};
> 
> It's odd that this patch adds this ops structure but doesn't actually
> start using it until the next patch.

I wanted to separate iomap changes with xfs changes so it's easier
to go through, but I fine with merging these two.

-- 
- Andrey