From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ee0-f52.google.com (mail-ee0-f52.google.com [74.125.83.52]) by kanga.kvack.org (Postfix) with ESMTP id 71E706B0037 for ; Mon, 12 May 2014 03:51:58 -0400 (EDT) Received: by mail-ee0-f52.google.com with SMTP id e53so4347522eek.11 for ; Mon, 12 May 2014 00:51:57 -0700 (PDT) Received: from mout.kundenserver.de (mout.kundenserver.de. [212.227.17.24]) by mx.google.com with ESMTPS id z48si9832157eey.293.2014.05.12.00.51.56 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 12 May 2014 00:51:57 -0700 (PDT) From: Arnd Bergmann Subject: Re: [RFC][PATCH 2/2] ARM: ioremap: Add IO mapping space reused support. Date: Mon, 12 May 2014 09:51:41 +0200 Message-ID: <5146762.jba3IJe7xt@wuerfel> In-Reply-To: <1399861195-21087-3-git-send-email-superlibj8301@gmail.com> References: <1399861195-21087-1-git-send-email-superlibj8301@gmail.com> <1399861195-21087-3-git-send-email-superlibj8301@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: owner-linux-mm@kvack.org List-ID: To: linux-arm-kernel@lists.infradead.org Cc: Richard Lee , linux@arm.linux.org.uk, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Richard Lee On Monday 12 May 2014 10:19:55 Richard Lee wrote: > For the IO mapping, for the same physical address space maybe > mapped more than one time, for example, in some SoCs: > 0x20000000 ~ 0x20001000: are global control IO physical map, > and this range space will be used by many drivers. > And then if each driver will do the same ioremap operation, we > will waste to much malloc virtual spaces. > > This patch add IO mapping space reused support. > > Signed-off-by: Richard Lee What happens if the first driver then unmaps the area? Arnd -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org