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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Sat, 22 Feb 2020 18:14:45 -0800
Message-ID: <CAHk-=whzmY4RdkqtitWVB=OJvHG-8_VLZrU1oXBX8b+5qJKBag@mail.gmail.com>
Subject: Re: [RFC][PATCH v2 14/34] new step_into() flag: WALK_NOFOLLOW
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Sat, Feb 22, 2020 at 5:20 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
>         if (likely(!d_is_symlink(path->dentry)) ||
> -          !(flags & WALK_FOLLOW || nd->flags & LOOKUP_FOLLOW)) {
> +          !(flags & WALK_FOLLOW || nd->flags & LOOKUP_FOLLOW) ||
> +          flags & WALK_NOFOLLOW) {

Humor me, and don't mix bitwise ops with logical boolean ops without
parentheses, ok?

And yes, the old code did it too, so it's not a new thing.

But as it gets even more complex, let's just generally strive for doing

   (a & b) || (c & d)

instead of

   a & b || c & d

to make it easier to mentally see the grouping.

               Linus