Re: [PATCH 2/3] ceph: Uninline the data on a file opened for writing

[Matthew Wilcox <willy@xxxxxxxxxxxxx>]

On Mon, Jan 17, 2022 at 04:59:35PM +0000, David Howells wrote:
> Matthew Wilcox <willy@xxxxxxxxxxxxx> wrote:
> 
> > > +	if (folio_test_uptodate(folio))
> > > +		goto out_put_folio;
> > 
> > Er ... if (!folio_test_uptodate(folio)), perhaps?  And is it even
> > worth testing if read_mapping_folio() returned success?  I feel like
> > we should take ->readpage()'s word for it that success means the
> > folio is now uptodate.
> 
> Actually, no, I shouldn't need to do this since it comes out with the page
> lock still held.

No.  The page is unlocked upon IO completion.  After calling ->readpage,
                folio_wait_locked(folio);