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;
Date:   Sat, 8 May 2021 22:46:23 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Linus Torvalds <torvalds@linux-foundation.org>
Cc:     Jia He <justin.he@arm.com>, Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Jonathan Corbet <corbet@lwn.net>,
        Al Viro <viro@ftp.linux.org.uk>,
        Heiko Carstens <hca@linux.ibm.com>,
        Vasily Gorbik <gor@linux.ibm.com>,
        Christian Borntraeger <borntraeger@de.ibm.com>,
        "Eric W . Biederman" <ebiederm@xmission.com>,
        "Darrick J. Wong" <darrick.wong@oracle.com>,
        "Peter Zijlstra (Intel)" <peterz@infradead.org>,
        Ira Weiny <ira.weiny@intel.com>,
        Eric Biggers <ebiggers@google.com>,
        "Ahmed S. Darwish" <a.darwish@linutronix.de>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-s390 <linux-s390@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH RFC 1/3] fs: introduce helper d_path_fast()
Message-ID: <YJcUvwo2pn0JEs27@zeniv-ca.linux.org.uk>
References: <20210508122530.1971-1-justin.he@arm.com>
 <20210508122530.1971-2-justin.he@arm.com>
 <CAHk-=wgSFUUWJKW1DXa67A0DXVzQ+OATwnC3FCwhqfTJZsvj1A@mail.gmail.com>
 <YJbivrA4Awp4FXo8@zeniv-ca.linux.org.uk>
 <CAHk-=whZhNXiOGgw8mXG+PTpGvxnRG1v5_GjtjHpoYXd2Fn_Ow@mail.gmail.com>
 <YJb9KFBO7MwJeDHz@zeniv-ca.linux.org.uk>
 <CAHk-=wjgXvy9EoE1_8KpxE9P3J_a-NF7xRKaUzi9MPSCmYnq+Q@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAHk-=wjgXvy9EoE1_8KpxE9P3J_a-NF7xRKaUzi9MPSCmYnq+Q@mail.gmail.com>
Sender: Al Viro <viro@ftp.linux.org.uk>
Precedence: bulk

On Sat, May 08, 2021 at 03:17:44PM -0700, Linus Torvalds wrote:
> On Sat, May 8, 2021 at 2:06 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
> >
> > On Sat, May 08, 2021 at 01:39:45PM -0700, Linus Torvalds wrote:
> >
> > > +static inline int prepend_entries(struct prepend_buffer *b, const struct path *path, const struct path *root, struct mount *mnt)
> >
> > If anything, s/path/dentry/, since vfsmnt here will be equal to &mnt->mnt all along.
> 
> Too subtle for me.
> 
> And is it? Because mnt is from
> 
>      mnt = real_mount(path->mnt);
> 
> earlier, while vfsmount is plain "path->mnt".

static inline struct mount *real_mount(struct vfsmount *mnt)
{
        return container_of(mnt, struct mount, mnt);
}