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: <1591611829-23071-1-git-send-email-agordeev@linux.ibm.com> <CAHp75VcFdrvNMj0TL8ZHxShqqGDM31Hy8vitmn9HOPjZ6f9uYw@mail.gmail.com>
In-Reply-To: <CAHp75VcFdrvNMj0TL8ZHxShqqGDM31Hy8vitmn9HOPjZ6f9uYw@mail.gmail.com>
From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Mon, 8 Jun 2020 15:08:22 +0300
Message-ID: <CAHp75Ve98sbs9do=vD7fk+iWWgTPfQ=8HT1Nh4ehBtdtp7joKQ@mail.gmail.com>
Subject: Re: [PATCH RESEND2] lib: fix bitmap_parse() on 64-bit big endian archs
To:     Alexander Gordeev <agordeev@linux.ibm.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-s390@vger.kernel.org, Stable <stable@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Yury Norov <yury.norov@gmail.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Amritha Nambiar <amritha.nambiar@intel.com>,
        Arnaldo Carvalho de Melo <acme@redhat.com>,
        Chris Wilson <chris@chris-wilson.co.uk>,
        Kees Cook <keescook@chromium.org>,
        Matthew Wilcox <willy@infradead.org>,
        Miklos Szeredi <mszeredi@redhat.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Steffen Klassert <steffen.klassert@secunet.com>,
        "Tobin C . Harding" <tobin@kernel.org>,
        Vineet Gupta <vineet.gupta1@synopsys.com>,
        Will Deacon <will.deacon@arm.com>,
        Willem de Bruijn <willemb@google.com>
Content-Type: text/plain; charset="UTF-8"
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Jun 8, 2020 at 3:03 PM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> On Mon, Jun 8, 2020 at 1:26 PM Alexander Gordeev <agordeev@linux.ibm.com> wrote:

...

> Can't we simple do
>
>         int chunk_index = 0;
>         ...
>         do {
> #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN)
>                end = bitmap_get_x32_reverse(start, end,
> bitmap[chunk_index ^ 1]);
> #else
>                end = bitmap_get_x32_reverse(start, end, bitmap[chunk_index]);
> #endif
>         ...
>         } while (++chunk_index);
>
> ?

And moreover, we simple can replace bitmap by maskp here, and drop it
from definition block.

-- 
With Best Regards,
Andy Shevchenko