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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 autolearn=unavailable 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 B0F5CC2D0E5 for ; Mon, 30 Mar 2020 17:45:14 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8114D2073B for ; Mon, 30 Mar 2020 17:45:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8114D2073B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 5DC3D87C25; Mon, 30 Mar 2020 17:45:14 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id m1Pd+vmwOQFI; Mon, 30 Mar 2020 17:45:13 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id B87F087838; Mon, 30 Mar 2020 17:45:13 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id A0022C1AE8; Mon, 30 Mar 2020 17:45:13 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id A2136C07FF for ; Mon, 30 Mar 2020 17:45:12 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 90E6D87928 for ; Mon, 30 Mar 2020 17:45:12 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id nXSFBNjqv9Fj for ; Mon, 30 Mar 2020 17:45:12 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by whitealder.osuosl.org (Postfix) with ESMTPS id EA8C387838 for ; Mon, 30 Mar 2020 17:45:11 +0000 (UTC) IronPort-SDR: aON/s4W+ZyZb74Gs13sHfIXoR+bgZNBxVJXBvuEDfu8Cn93vb2Hl2B3FHhct3ZU9RZpj48g+up lx+4PEsFj97A== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Mar 2020 10:45:11 -0700 IronPort-SDR: hFmrBJo7Lw54DVGU1sjW1hTTNaRCgzAIqFjN2qN/JhxkRSfx9I9NRSzPJByrrcvg0NjHEQp+ca EQYXm41zyQ2g== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,325,1580803200"; d="scan'208";a="422004388" Received: from jacob-builder.jf.intel.com (HELO jacob-builder) ([10.7.199.155]) by orsmga005.jf.intel.com with ESMTP; 30 Mar 2020 10:45:10 -0700 Date: Mon, 30 Mar 2020 10:50:57 -0700 From: Jacob Pan To: Lu Baolu Subject: Re: [PATCH V10 03/11] iommu/vt-d: Add a helper function to skip agaw Message-ID: <20200330105057.222c5928@jacob-builder> In-Reply-To: References: <1584746861-76386-1-git-send-email-jacob.jun.pan@linux.intel.com> <1584746861-76386-4-git-send-email-jacob.jun.pan@linux.intel.com> Organization: OTC X-Mailer: Claws Mail 3.13.2 (GTK+ 2.24.30; x86_64-pc-linux-gnu) MIME-Version: 1.0 Cc: "Tian, Kevin" , "Raj, Ashok" , Jean-Philippe Brucker , "iommu@lists.linux-foundation.org" , LKML , Alex Williamson , David Woodhouse , Jonathan Cameron X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" On Sun, 29 Mar 2020 15:20:55 +0800 Lu Baolu wrote: > On 2020/3/27 19:53, Tian, Kevin wrote: > >> From: Jacob Pan > >> Sent: Saturday, March 21, 2020 7:28 AM > >> > >> Signed-off-by: Jacob Pan > > > > could you elaborate in which scenario this helper function is > > required? > > I added below commit message: > > An Intel iommu domain uses 5-level page table by default. If the > iommu that the domain tries to attach supports less page levels, > the top level page tables should be skipped. Add a helper to do > this so that it could be used in other places. > Thanks Baolu, I will also add this to my v11, it might save you some time :) > Best regards, > baolu > > > > >> --- > >> drivers/iommu/intel-pasid.c | 22 ++++++++++++++++++++++ > >> 1 file changed, 22 insertions(+) > >> > >> diff --git a/drivers/iommu/intel-pasid.c > >> b/drivers/iommu/intel-pasid.c index 22b30f10b396..191508c7c03e > >> 100644 --- a/drivers/iommu/intel-pasid.c > >> +++ b/drivers/iommu/intel-pasid.c > >> @@ -500,6 +500,28 @@ int intel_pasid_setup_first_level(struct > >> intel_iommu *iommu, > >> } > >> > >> /* > >> + * Skip top levels of page tables for iommu which has less agaw > >> + * than default. Unnecessary for PT mode. > >> + */ > >> +static inline int iommu_skip_agaw(struct dmar_domain *domain, > >> + struct intel_iommu *iommu, > >> + struct dma_pte **pgd) > >> +{ > >> + int agaw; > >> + > >> + for (agaw = domain->agaw; agaw > iommu->agaw; agaw--) { > >> + *pgd = phys_to_virt(dma_pte_addr(*pgd)); > >> + if (!dma_pte_present(*pgd)) { > >> + return -EINVAL; > >> + } > >> + } > >> + pr_debug_ratelimited("%s: pgd: %llx, agaw %d d_agaw %d\n", > >> __func__, (u64)*pgd, > >> + iommu->agaw, domain->agaw); > >> + > >> + return agaw; > >> +} > >> + > >> +/* > >> * Set up the scalable mode pasid entry for second only > >> translation type. */ > >> int intel_pasid_setup_second_level(struct intel_iommu *iommu, > >> -- > >> 2.7.4 > > [Jacob Pan] _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu