From patchwork Mon Apr 4 05:05:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12799873 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 8B754C4332F for ; Mon, 4 Apr 2022 05:06:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1377327AbiDDFIl (ORCPT ); Mon, 4 Apr 2022 01:08:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48064 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1377321AbiDDFId (ORCPT ); Mon, 4 Apr 2022 01:08:33 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E190B3614D; Sun, 3 Apr 2022 22:06:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=PXzvxDuJ7dtq4MEwSJLJWBZwmoZU9P9omOl6CdJuIoM=; b=J0ixhsO+YSmFk3veuPhfX4XbNN fnLuVNVyiMyuqHMjG9Nm2j1QpkedDteZ/bUxB/nstVQR1kzCVf1HfyhjPHMtYmFcYkI5XO+PU1PO8 vYnXgpo+osZWDdaHlagIdcKjUWiK3YcXno80RpIJtk3hBVg0z5HbCGdJRO885gGbDdwICtCuMfsc4 LXknn7SUV16b1hVCB4GHdvg/UQJBOvxOZtFjUgeqmW9MWS9YXRDw/YqxSnJzydpaFaMXqkG9L52sO t12p1tMKTEuj//lEDkvoIbVNRfFdfHubUQBxqnFTG6Pyn9uHx25It5RZIGXV/Wtps3V7DHTPl4SYn PpSm/Nkg==; Received: from 089144211060.atnat0020.highway.a1.net ([89.144.211.60] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1nbEv3-00D8uv-7w; Mon, 04 Apr 2022 05:06:26 +0000 From: Christoph Hellwig To: iommu@lists.linux-foundation.org Cc: x86@kernel.org, Anshuman Khandual , Tom Lendacky , Konrad Rzeszutek Wilk , Stefano Stabellini , Boris Ostrovsky , Juergen Gross , Joerg Roedel , David Woodhouse , Lu Baolu , Robin Murphy , linux-arm-kernel@lists.infradead.org, xen-devel@lists.xenproject.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux-hyperv@vger.kernel.org, tboot-devel@lists.sourceforge.net, linux-pci@vger.kernel.org, Stefano Stabellini Subject: [PATCH 05/15] arm/xen: don't check for xen_initial_domain() in xen_create_contiguous_region Date: Mon, 4 Apr 2022 07:05:49 +0200 Message-Id: <20220404050559.132378-6-hch@lst.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20220404050559.132378-1-hch@lst.de> References: <20220404050559.132378-1-hch@lst.de> MIME-Version: 1.0 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-mips@vger.kernel.org From: Stefano Stabellini It used to be that Linux enabled swiotlb-xen when running a dom0 on ARM. Since f5079a9a2a31 "xen/arm: introduce XENFEAT_direct_mapped and XENFEAT_not_direct_mapped", Linux detects whether to enable or disable swiotlb-xen based on the new feature flags: XENFEAT_direct_mapped and XENFEAT_not_direct_mapped. However, there is still a leftover xen_initial_domain() check in xen_create_contiguous_region. Remove the check as xen_create_contiguous_region is only called by swiotlb-xen during initialization. If xen_create_contiguous_region is called, we know Linux is running 1:1 mapped so there is no need for additional checks. Also update the in-code comment. Signed-off-by: Stefano Stabellini Signed-off-by: Christoph Hellwig --- arch/arm/xen/mm.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c index a7e54a087b802..28c2070602535 100644 --- a/arch/arm/xen/mm.c +++ b/arch/arm/xen/mm.c @@ -122,10 +122,7 @@ int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order, unsigned int address_bits, dma_addr_t *dma_handle) { - if (!xen_initial_domain()) - return -EINVAL; - - /* we assume that dom0 is mapped 1:1 for now */ + /* the domain is 1:1 mapped to use swiotlb-xen */ *dma_handle = pstart; return 0; }