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 X-Spam-Level: X-Spam-Status: No, score=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 722B3C352BE for ; Thu, 16 Apr 2020 12:13:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 545BB20774 for ; Thu, 16 Apr 2020 12:13:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="uPEh7nQY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2635068AbgDPMNk (ORCPT ); Thu, 16 Apr 2020 08:13:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44192 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2635002AbgDPMNi (ORCPT ); Thu, 16 Apr 2020 08:13:38 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2CAB8C061A0C; Thu, 16 Apr 2020 05:13:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=hp6+eCj2O2nxWa/wGv8G7WCsIo0VMT1PsA9CYyFBw9A=; b=uPEh7nQY1JKkhF8C0Y4y2Gmad+ 0Lh9YxbB3n3bpZKSCTfe6apdDsHEJQ8+1fnAfMJYOQ7Ql+RYgwCiCPEay95+4hAhiUPJevlzeX1fJ juawpIUiGFu5mfa45bPWKqLkW/n9s5rroA3MynnjLIq7Qat6n1jaBQx75J3NNZelUA4YrqkUuGVcz H4Y2Zaeu42mCsHRkgGXpP+lVm6OKcx1KkTmiiHaNW3oV6yz92qPAmnFt+DrohrYDUCVX35t3XPvgO I1F0/d5RJPxCiBLE4f1cc1WmYObAzPqAFWgla4SAq3SvBWHFY87AaCOmi+Lt3b0XoTejUhCJEzA40 t2381FKw==; Received: from hch by bombadil.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jP3Oe-0002ua-05; Thu, 16 Apr 2020 12:13:32 +0000 Date: Thu, 16 Apr 2020 05:13:31 -0700 From: Christoph Hellwig To: Jean-Philippe Brucker Cc: Christoph Hellwig , iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, joro@8bytes.org, catalin.marinas@arm.com, will@kernel.org, robin.murphy@arm.com, kevin.tian@intel.com, baolu.lu@linux.intel.com, Jonathan.Cameron@huawei.com, jacob.jun.pan@linux.intel.com, christian.koenig@amd.com, zhangfei.gao@linaro.org, jgg@ziepe.ca, xuzaibo@huawei.com Subject: Re: [PATCH v5 02/25] iommu/sva: Manage process address spaces Message-ID: <20200416121331.GA18661@infradead.org> References: <20200414170252.714402-1-jean-philippe@linaro.org> <20200414170252.714402-3-jean-philippe@linaro.org> <20200416072852.GA32000@infradead.org> <20200416085402.GB1286150@myrica> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200416085402.GB1286150@myrica> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Thu, Apr 16, 2020 at 10:54:02AM +0200, Jean-Philippe Brucker wrote: > On Thu, Apr 16, 2020 at 12:28:52AM -0700, Christoph Hellwig wrote: > > > + rcu_read_lock(); > > > + hlist_for_each_entry_rcu(bond, &io_mm->devices, mm_node) > > > + io_mm->ops->invalidate(bond->sva.dev, io_mm->pasid, io_mm->ctx, > > > + start, end - start); > > > + rcu_read_unlock(); > > > +} > > > > What is the reason that the devices don't register their own notifiers? > > This kinds of multiplexing is always rather messy, and you do it for > > all the methods. > > This sends TLB and ATC invalidations through the IOMMU, it doesn't go > through device drivers I don't think we mean the same thing, probably because of my rather imprecise use of the word device. What I mean is that the mmu_notifier should not be embedded into the io_mm structure (whch btw, seems to have a way to generic name, just like all other io_* prefixed names), but instead into the iommu_bond structure. That avoid the whole multiplexing layer.