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Date:   Wed, 28 Jun 2023 19:13:32 -0700
From:   Ira Weiny <ira.weiny@intel.com>
To:     "Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
        Matthew Wilcox <willy@infradead.org>
CC:     Sumitra Sharma <sumitraartsy@gmail.com>,
        Hans de Goede <hdegoede@redhat.com>,
        <linux-fsdevel@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        Ira Weiny <ira.weiny@intel.com>,
        "Deepak R Varma" <drv@mailo.com>
Subject: Re: [PATCH] fs/vboxsf: Replace kmap() with kmap_local_{page, folio}()
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Fabio M. De Francesco wrote:
> On gioved? 29 giugno 2023 00:23:54 CEST Fabio M. De Francesco wrote:
> 
> [...]
> 
> > 
> > Shouldn't we call folio_lock() to lock the folio to be able to unlock with
> > folio_unlock()?
> 
> Sorry, I wanted to write "If so, I can't find either a folio_lock() or a 
> page_lock() in this filesystem.".

Check the documentation for read_folio:

	... "The filesystem should unlock the folio once the read has
	completed, whether it was successful or not." ...

Ira