From patchwork Mon Mar 1 07:44:31 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 12108885 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 4401EC433DB for ; Mon, 1 Mar 2021 07:46:28 +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 0BF6564DE7 for ; Mon, 1 Mar 2021 07:46:28 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0BF6564DE7 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.91277.172479 (Exim 4.92) (envelope-from ) id 1lGdG0-0003Fl-6y; Mon, 01 Mar 2021 07:46:20 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 91277.172479; Mon, 01 Mar 2021 07:46:20 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lGdG0-0003Fd-2K; Mon, 01 Mar 2021 07:46:20 +0000 Received: by outflank-mailman (input) for mailman id 91277; Mon, 01 Mar 2021 07:46:18 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lGdFy-00036y-E0 for xen-devel@lists.xenproject.org; Mon, 01 Mar 2021 07:46:18 +0000 Received: from casper.infradead.org (unknown [2001:8b0:10b:1236::1]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 3f8fe213-b4ce-4d70-a9c9-b55cac12f660; Mon, 01 Mar 2021 07:46:15 +0000 (UTC) Received: from [2001:4bb8:19b:e4b7:cdf9:733f:4874:8eb4] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.94 #2 (Red Hat Linux)) id 1lGdFm-00FRDp-Lh; Mon, 01 Mar 2021 07:46:08 +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: 3f8fe213-b4ce-4d70-a9c9-b55cac12f660 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=JFey0nQH0q27BLg8sKUeuXSyZDiQiQFLOD6BixvKeyU=; b=NOzDrThXk5sQLHtG3a7GXeBGS9 H2XGITYrLulEacH0a8AvtD4GcR3a2s77sP1xJjnehH3ArsbGm+hD5Yg+R4px9hPi+g+Hqawj5XasA USCZkvxqssnycydmnC4rU9Kn3Dp7ojnB+xcinZ1+dr2f3ywKfxV6zOcD7Kwh/7lBlruP/9QUg21lZ FZB2z4KkS3r112xjPrzwRHn0SffHvc9LiSxaQmlgIEzvoxWUQ9A+bGnTQDUWoUtbAOlVvg3mcywgr 5zo9Ej6FKEwbLIhTjZHYLebzvkQLYCHjA/PtqDXKiu7RlyNYJviJ7iXcpJ36kfbd/1Ijq+NNQpDOs QO9Tuoyw==; 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 09/14] swiotlb: lift the double initialization protection from xen-swiotlb Date: Mon, 1 Mar 2021 08:44:31 +0100 Message-Id: <20210301074436.919889-10-hch@lst.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210301074436.919889-1-hch@lst.de> References: <20210301074436.919889-1-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 1a31ddf7139799..060eeb056486f5 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 388d9be35b5795..ebe7c123e27e52 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -229,6 +229,10 @@ 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; @@ -367,6 +371,10 @@ 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;