From:   "Fabio M. De Francesco" <fmdefrancesco@gmail.com>
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Christoph Hellwig <hch@infradead.org>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        Ira Weiny <ira.weiny@intel.com>
Subject: Re: [PATCH v3 4/4] fs/sysv: Replace kmap() with kmap_local_page()
Date:   Mon, 23 Jan 2023 18:03:07 +0100
Message-ID: <8172994.T7Z3S40VBb@suse>
In-Reply-To: <Y8oWsiNWSXlDNn5i@ZenIV>
References: <20230119153232.29750-1-fmdefrancesco@gmail.com>
 <20230119153232.29750-5-fmdefrancesco@gmail.com> <Y8oWsiNWSXlDNn5i@ZenIV>
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On Thu, Jan 19, 2023 at 04:32:32PM +0100, Fabio M. De Francesco wrote:
> @@ -228,6 +239,12 @@ int sysv_delete_entry(struct sysv_dir_entry *de, str=
uct=20
page *page)
> {
> struct inode *inode =3D page->mapping->host;
> loff_t pos =3D page_offset(page) + offset_in_page(de);
> +       /*
> +        * The "de" dentry points somewhere in the same page whose we nee=
d=20
the
> +        * address of; therefore, we can simply get the base address "kad=
dr"=20
by
> +        * masking the previous with PAGE_MASK.
> +        */
> +       char *kaddr =3D (char *)((unsigned long)de & PAGE_MASK);

er...  ITYM "therefore we can pass de to dir_put_page() and get rid of that=
=20
kaddr
thing"...

Anyway, with that change the series rebased and applied on top of Christoph=
's=20
sysv
patch.

On venerd=EC 20 gennaio 2023 05:21:06 CET Al Viro wrote:
> On Thu, Jan 19, 2023 at 04:32:32PM +0100, Fabio M. De Francesco wrote:
> > -inline void dir_put_page(struct page *page)
> > +inline void dir_put_page(struct page *page, void *page_addr)
> >=20
> >  {
> >=20
> > -	kunmap(page);
> > +	kunmap_local(page_addr);
>=20
> ... and that needed to be fixed - at some point "round down to beginning =
of
> page" got lost in rebasing...

Sorry for this late reply.
Unfortunately, at the moment, I have too little free time for kernel=20
development.

@Al...

I merged the two messages from you because they are related to changes to t=
he=20
same patch. I would like to know if I am interpreting both correctly or not.

=46rom your posts it sounds like you're saying you made the necessary chang=
es=20
and then applied this series on top of Christoph's latest patch to fs/sysv,=
 so=20
don't expect me to push a new version.

Did I understand correctly or am I missing something?
Anyway, if my interpretation is correct, thank you very much.

Can you please confirm that I understood correctly or not?

Thank you,

=46abio