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Message-ID: <0ac0c93919e40d0c610419fa12e852e889d490e6.camel@perches.com>
Subject: Re: [PATCH v2 5/5] Input: evdev - Switch to bitmap_zalloc()
From:   Joe Perches <joe@perches.com>
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Yury Norov <ynorov@caviumnetworks.com>, agk@redhat.com,
        Mike Snitzer <snitzer@redhat.com>, dm-devel@redhat.com,
        shli@kernel.org, linux-raid@vger.kernel.org,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        linux-input <linux-input@vger.kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Mika Westerberg <mika.westerberg@linux.intel.com>
Date:   Mon, 18 Jun 2018 13:40:20 -0700
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On Mon, 2018-06-18 at 22:56 +0300, Andy Shevchenko wrote:
> On Mon, Jun 18, 2018 at 6:49 PM, Joe Perches <joe@perches.com> wrote:
> > Perhaps bitmap_dup_user [or some better name] could or should
> > be one of the helpers.
> 
> Can you help with estimation how many existing users need this kind of
> functionality? One of them evdev, which has an open coded variant.

My estimation via cocci script below is 1 existing user,
so it's almost certainly not worthwhile.

$ cat copy_from_user.cocci 
@@
unsigned long *p;
expression e1, e2;
@@

*	copy_from_user(p, e1, e2)