From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B7346C43334 for ; Mon, 11 Jul 2022 16:10:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=m9eGH1um61iqPlc2V9KzP/qZP/532lTrpCrYtTbYveU=; b=Ifehdio77mKHZa qrXSAursb/x7MfZ/unDNj7704phAt5hmdtqmWHWY4wbe6FJ8qJlZJ2WaSn3MSRnLu1lElLlLw2adI 8O5EzOJ2gBiTyf05E1a8wbrI4gVBpI9zCA0jW/fwOSqExA6GO5wjDbyP+IUt7YAHyrEB8Nn4bnlOl hwnvWXdYsfQNfWXWc4X6bd9yCDQYSODNrLt79rRlFMJfS0r+ov8uUi4KT/s5HH1IQXqF/g7dqwEa2 rIztiH5PIz/OpTlRn47XyWzoml1Lp63711oUdSd3d/sg/0atvwNL23CixFAT5to8W9657MK9Fj6gg JhI4tJWKGT54FC61ldvg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1oAvz3-0038Wh-Uq; Mon, 11 Jul 2022 16:10:06 +0000 Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1oAvyt-0038S1-Fb; Mon, 11 Jul 2022 16:09:55 +0000 Date: Mon, 11 Jul 2022 09:09:55 -0700 From: Christoph Hellwig To: Li Chen Cc: Christoph Hellwig , Catalin Marinas , Will Deacon , Rob Herring , Frank Rowand , Andrew Morton , linux-arm-kernel , linux-kernel , devicetree , linux-mm Subject: Re: [PATCH 0/4] add struct page and Direct I/O support to reserved memory Message-ID: References: <20220711122459.13773-1-me@linux.beauty> <181ee01d384.b809bd01412268.496620746959082770@linux.beauty> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <181ee01d384.b809bd01412268.496620746959082770@linux.beauty> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Tue, Jul 12, 2022 at 12:05:06AM +0800, Li Chen wrote: > My use case has been stated in the cover letter, but our driver is not ready for upstream yet. Which means we can't review the use case. I'd suggest you come back when you submit your driver. > With DMA allocator, we can access buffer in kernel space, not userspace, however, this patch Take a look at dma_mmap_* on how to map DMA coherent allocations to usersapce. This is of course easily possible. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel