Date:   Wed, 15 Mar 2023 16:08:46 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     Hannes Reinecke <hare@suse.de>
Cc:     Pankaj Raghav <p.raghav@samsung.com>, hubcap@omnibond.com,
        senozhatsky@chromium.org, martin@omnibond.com, minchan@kernel.org,
        viro@zeniv.linux.org.uk, brauner@kernel.org, axboe@kernel.dk,
        akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
        linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-mm@kvack.org, gost.dev@samsung.com, mcgrof@kernel.org,
        devel@lists.orangefs.org
Subject: Re: [RFC PATCH 2/3] mpage: use bio_for_each_folio_all in
 mpage_end_io()
Message-ID: <ZBHtjrk52/TTPU/F@casper.infradead.org>
References: <20230315123233.121593-1-p.raghav@samsung.com>
 <CGME20230315123235eucas1p1bd62cb2aab435727880769f2e57624fd@eucas1p1.samsung.com>
 <20230315123233.121593-3-p.raghav@samsung.com>
 <64a5e85e-4018-ed7d-29d4-db12af290899@suse.de>
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On Wed, Mar 15, 2023 at 03:52:15PM +0100, Hannes Reinecke wrote:
> On 3/15/23 13:32, Pankaj Raghav wrote:
> > Use bio_for_each_folio_all to iterate through folios in a bio so that
> > the folios can be directly passed to the folio_endio() function.
> > +	bio_for_each_folio_all(fi, bio)
> > +		folio_endio(fi.folio, bio_op(bio),
> > +			    blk_status_to_errno(bio->bi_status));
> >   	bio_put(bio);
> >   }
> 
> Ah. Here it is.
> 
> I would suggest merge these two patches.

The right way to have handled this patch series was:

1. Introduce a new folio_endio() [but see Christoph's mail on why we
shouldn't do that]
2-n convert callers to use folios directly
n+1 remove page_endio() entirely.

Note that patch n+1 might not be part of this patch series; sometimes
it takes a while to convert all callers to use folios.

I very much dislike the way this was done by pushing the page_folio()
call into each of the callers because it makes the entire series hard to
review.