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From:   Vishal Moola <vishal.moola@gmail.com>
Date:   Wed, 21 Dec 2022 09:17:30 -0800
Message-ID: <CAOzc2pzoyBg=jgYNNfsmum9tKFOAy65zVsEyDE3vKoiti7FZDA@mail.gmail.com>
Subject: Re: [RFC PATCH] f2fs: Convert f2fs_write_cache_pages() to use filemap_get_folios_tag()
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Chao Yu <chao@kernel.org>, linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, linux-mm@kvack.org,
        fengnanchang@gmail.com, linux-fsdevel@vger.kernel.org
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On Thu, Dec 15, 2022 at 10:45 AM Matthew Wilcox <willy@infradead.org> wrote:
>
> On Thu, Dec 15, 2022 at 09:48:41AM +0800, Chao Yu wrote:
> > On 2022/12/13 3:13, Vishal Moola (Oracle) wrote:
> > > +add_more:
> > > +                   pages[nr_pages] = folio_page(folio,idx);
> > > +                   folio_ref_inc(folio);
> >
> > It looks if CONFIG_LRU_GEN is not set, folio_ref_inc() does nothing. For those
> > folios recorded in pages array, we need to call folio_get() here to add one more
> > reference on each of them?
>
> static inline void folio_get(struct folio *folio)
> {
>         VM_BUG_ON_FOLIO(folio_ref_zero_or_close_to_overflow(folio), folio);
>         folio_ref_inc(folio);
> }
>
> That said, folio_ref_inct() is very much MM-internal and filesystems
> should be using folio_get(), so please make that modification in the
> next revision, Vishal.

Ok, I'll go through and fix all of those in the next version.