From patchwork Sun Feb 7 16:09:32 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12073153 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=-16.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 D3F21C433E0 for ; Sun, 7 Feb 2021 16:10:24 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 9412264DF2 for ; Sun, 7 Feb 2021 16:10:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9412264DF2 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.82434.152289 (Exim 4.92) (envelope-from ) id 1l8mdd-00057y-5r; Sun, 07 Feb 2021 16:10:17 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 82434.152289; Sun, 07 Feb 2021 16:10:17 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1l8mdd-00057q-1w; Sun, 07 Feb 2021 16:10:17 +0000 Received: by outflank-mailman (input) for mailman id 82434; Sun, 07 Feb 2021 16:10:15 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1l8mdb-00042X-Iy for xen-devel@lists.xenproject.org; Sun, 07 Feb 2021 16:10:15 +0000 Received: from casper.infradead.org (unknown [2001:8b0:10b:1236::1]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id f3c0691c-47f9-4d9f-939d-c11edf2a73f0; Sun, 07 Feb 2021 16:09:52 +0000 (UTC) Received: from [2001:4bb8:184:7d04:4590:5583:6cb7:77c7] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1l8md9-004tnJ-Fd; Sun, 07 Feb 2021 16:09:48 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: f3c0691c-47f9-4d9f-939d-c11edf2a73f0 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; 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=9exQlU2bM+z89vz4InpfIN+OgEoSYW+vKDhpQvUzWEc=; b=fmNr0UgbkUNuM/6xYoYIl1Rrvu NjXGGNO7rb6ADI6vT40u/zONLvuSngV72/jHsqgPSgPdAN+wEUDyiIdoRTVpEZmLqJSlRXchWUKGA eluKXm1mFdJJn++1DfZvR2YO+X0JUshTE3gzwf6gjtlHNPTzbVGePGmIGFxgBXOxNKJfI1KkyC2Pb nMwmcXMNzuG2JOFRxdZzeeKNS4HQwVd/0Q/gujMYFOHIZXrOk3w8PuAmWcqmAE1DUqnlU6d7QuM6s o+Kwv+YAPHNTcLEXNvfSe7Cnz+d04XyeVlR7knzJwEz+D3x/VVO20+JVl3mfPkAXYtMUG2hKTNqpL Zvtma1Pw==; From: Christoph Hellwig To: Konrad Rzeszutek Wilk Cc: Michael Ellerman , Dongli Zhang , Claire Chang , xen-devel@lists.xenproject.org, linuxppc-dev@lists.ozlabs.org, iommu@lists.linux-foundation.org Subject: [PATCH 6/8] swiotlb: lift the double initialization protection from xen-swiotlb Date: Sun, 7 Feb 2021 17:09:32 +0100 Message-Id: <20210207160934.2955931-7-hch@lst.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210207160934.2955931-1-hch@lst.de> References: <20210207160934.2955931-1-hch@lst.de> MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Lift the double initialization protection from xen-swiotlb to the core code to avoid exposing too many swiotlb internals. Also upgrade the check to a warning as it should not happen. Signed-off-by: Christoph Hellwig --- drivers/xen/swiotlb-xen.c | 7 ------- kernel/dma/swiotlb.c | 8 ++++++++ 2 files changed, 8 insertions(+), 7 deletions(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 6e0f2c5ecd1a2f..e6c8556e879ee6 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -172,12 +172,6 @@ int __ref xen_swiotlb_init(int verbose, bool early) bytes = nslabs << IO_TLB_SHIFT; order = get_order(bytes); - /* - * IO TLB memory already allocated. Just use it. - */ - if (io_tlb_start != 0) - goto end; - /* * Get IO TLB memory from any location. */ @@ -232,7 +226,6 @@ int __ref xen_swiotlb_init(int verbose, bool early) } else rc = swiotlb_late_init_with_tbl(start, nslabs); -end: if (!rc) swiotlb_set_max_segment(PAGE_SIZE); diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index adcc3c87e10078..a3737961ae5769 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -224,6 +224,10 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) unsigned long i, bytes; size_t alloc_size; + /* protect against double initialization */ + if (WARN_ON_ONCE(io_tlb_start)) + return -ENOMEM; + bytes = nslabs << IO_TLB_SHIFT; io_tlb_nslabs = nslabs; @@ -355,6 +359,10 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) { unsigned long i, bytes; + /* protect against double initialization */ + if (WARN_ON_ONCE(io_tlb_start)) + return -ENOMEM; + bytes = nslabs << IO_TLB_SHIFT; io_tlb_nslabs = nslabs;