Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
MIME-Version: 1.0
References: <20201123031751.36811-1-daeho43@gmail.com> <20201123031751.36811-2-daeho43@gmail.com>
 <20201123184821.GB3694916@gmail.com> <CACOAw_xEe=3H60njSfwJSToFnVbOHabUd2Nt=uZJLvCfxFgM4Q@mail.gmail.com>
 <X7xF8+jko5d71CKq@sol.localdomain>
In-Reply-To: <X7xF8+jko5d71CKq@sol.localdomain>
From:   Daeho Jeong <daeho43@gmail.com>
Date:   Tue, 24 Nov 2020 10:03:33 +0900
Message-ID: <CACOAw_xZCC3u08=ZB_Ugk-LJs1wJL3ByJhuxwNK9zOYqU46Jzg@mail.gmail.com>
Subject: Re: [f2fs-dev] [PATCH 2/2] f2fs: add F2FS_IOC_DECOMPRESS_FILE and F2FS_IOC_COMPRESS_FILE
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     linux-kernel@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Daeho Jeong <daehojeong@google.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Precedence: bulk

2020=EB=85=84 11=EC=9B=94 24=EC=9D=BC (=ED=99=94) =EC=98=A4=EC=A0=84 8:29, =
Eric Biggers <ebiggers@kernel.org>=EB=8B=98=EC=9D=B4 =EC=9E=91=EC=84=B1:
>
> On Tue, Nov 24, 2020 at 08:02:21AM +0900, Daeho Jeong wrote:
> > Jaegeuk,
> >
> > My mistake~
> >
> > Eric,
> >
> > What I want is like do_page_cache_ra(), but I used
> > page_cache_ra_unbounded() directly, because we already checked that
> > read is within i_size.
> >
> > Or we could use do_page_cache_ra(), but it might do the same check in i=
t again.
> > What do you think?
>
> page_cache_ra_unbounded() is basically a quirk for how fs-verity is imple=
mented
> in ext4 and f2fs.  I don't think people would be happy if it's used in ot=
her
> cases, where it's not needed.  Checking against i_size multiple times is =
fine.
>

Got your point. Thanks.

> >
> > I could add some description about these in
> > Documentation/filesystems/f2fs.rst and I implemented tests internally.
>
> Documentation in f2fs.rst sounds good.  All the f2fs ioctls should be
> documented there.
>
> The tests should be runnable by any kernel developer; "internal" tests ar=
en't
> very useful.  Could you add tests to xfstests?
>

Yes, I'll add all the internal test cases to xfstests soon~

> - Eric