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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 08637C433EF for ; Mon, 13 Jun 2022 06:05:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233803AbiFMGFG (ORCPT ); Mon, 13 Jun 2022 02:05:06 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36494 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229638AbiFMGE4 (ORCPT ); Mon, 13 Jun 2022 02:04:56 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 08EBF1027 for ; Sun, 12 Jun 2022 23:04:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Transfer-Encoding :Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To:From:Date: Sender:Reply-To:Content-ID:Content-Description; bh=b1PoY1uKlcNqy2edTiTsVL/coyRDE9FCOo38ncps/ZM=; b=asqORLv9fFtRmH0mbdAsX62PEY 2oM2wjfo4NwjYVsp3GvIcXnsJO9DKRj8XCXW1E4suTxpr2g8LP73vdRMEKnbzqlgoyXVfnbMS54bD FBTwd3vKQ1myxZku0vIkaOTi9LwMJKMefz6tfktugd6A88h7XFJ8zVDM64ozYM6Q5rABwX6AKb2fa 8zxSLwNzq9CLLB7mjw/mVXMIKzM5UZnMYu4GyUGLrYpMbVB2c2wQRdURbri0g+CmKZJ4dWe95IH7X ApNaap56yK/FeNrP1odSM3lUI36xBVvmY3EYL/xIb/6e2D8T1L0tLE8e0+gIuJwvSLdsxahG1pSYz SAgdlhuA==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1o0dBu-001aZ9-At; Mon, 13 Jun 2022 06:04:46 +0000 Date: Sun, 12 Jun 2022 23:04:46 -0700 From: Christoph Hellwig To: Dongli Zhang Cc: Christoph Hellwig , iommu@lists.linux-foundation.org, xen-devel@lists.xenproject.org, x86@kernel.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux-foundation.org, linux-kernel@vger.kernel.org, m.szyprowski@samsung.com, jgross@suse.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, sstabellini@kernel.org, mpe@ellerman.id.au, konrad.wilk@oracle.com, mst@redhat.com, jasowang@redhat.com, joe.jin@oracle.com Subject: Re: [PATCH RFC v1 4/7] swiotlb: to implement io_tlb_high_mem Message-ID: References: <20220609005553.30954-1-dongli.zhang@oracle.com> <20220609005553.30954-5-dongli.zhang@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 10, 2022 at 02:56:08PM -0700, Dongli Zhang wrote: > Since this patch file has 200+ lines, would you please help clarify what does > 'this' indicate? This indicates that any choice of a different swiotlb pools needs to be hidden inside of Ń•wiotlb. The dma mapping API already provides swiotlb the addressability requirement for the device. Similarly we already have a SWIOTLB_ANY flag that switches to a 64-bit buffer by default, which we can change to, or replace with a flag that allocates an additional buffer that is not addressing limited.