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=-8.7 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 C92BDC04AB3 for ; Thu, 9 May 2019 07:20:50 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 97AEA217D9 for ; Thu, 9 May 2019 07:20:50 +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="FnXQrJHU" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 97AEA217D9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 5B5BDB4B; Thu, 9 May 2019 07:20:50 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 7FA63AF7 for ; Thu, 9 May 2019 07:20:48 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id ED90A1FB for ; Thu, 9 May 2019 07:20:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=dHPcM7BToWSY7XBTx45AtDbkmyX1K9o4jR86GMXyrWY=; b=FnXQrJHUhhe9vAR/2fLP8tRF7 Di7W3Iao30bbViXAWg8zQHkmSzSqDScbjfSyWwxECcCw/QIyiZ2VwyWxI6oote2HhxVGV6JvvYGHU DGHbILgpPHBNfr2K93OqJaInQAN63uEd4XSP1zlTyFkiwB4uqrFM/7rScwHdU3Eva4syMG5fYyrqH YwWI505e5A2W8UK8K/bl1DjHrWEBB/iyj4cNQosK59L20lc/p7jMnJud1Rebq7sDjeCcBrAjRhn8C 6XGYuw28SADvfL7wQGN6ZiJktLnkjTXVCP09fYqwPkmFTS0hkcyLJ/57wajLhB3n/YBcWBpyBxkdP VCLWV4aXg==; Received: from 089144210233.atnat0019.highway.a1.net ([89.144.210.233] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.90_1 #2 (Red Hat Linux)) id 1hOdME-00067H-Jh; Thu, 09 May 2019 07:20:47 +0000 From: Christoph Hellwig To: Russell King Subject: [PATCH] ARM: dma-mapping: don't use the atomic pool for DMA_ATTR_NO_KERNEL_MAPPING Date: Thu, 9 May 2019 09:20:06 +0200 Message-Id: <20190509072006.727-1-hch@lst.de> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 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 Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org DMA allocations with the DMA_ATTR_NO_KERNEL_MAPPING do not return a kernel virtual address for use in driver, but are expected to be used entirely for userspace mappings and/or device private memory. Because of that we don't need to remap them as uncached, and thus don't need the atomic pool for non-blocking allocations. Note that using the DMA allocator with DMA_ATTR_NO_KERNEL_MAPPING from non-blocking context on a non-coherent device is actually broken without this patch as well, as we feed the address passes to dma_free_attrs directly to the genpool allocator, but for DMA_ATTR_NO_KERNEL_MAPPING allocations it actually contains the address of the first page pointer. Signed-off-by: Christoph Hellwig --- arch/arm/mm/dma-mapping.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index d029fa31624b..f74d824f8fc1 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -706,6 +706,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp, pgprot_t prot, bool is_coherent, unsigned long attrs, const void *caller) { + bool want_vaddr = !(attrs & DMA_ATTR_NO_KERNEL_MAPPING); u64 mask = get_coherent_dma_mask(dev); struct page *page = NULL; void *addr; @@ -717,7 +718,7 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, .gfp = gfp, .prot = prot, .caller = caller, - .want_vaddr = ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0), + .want_vaddr = want_vaddr, .coherent_flag = is_coherent ? COHERENT : NORMAL, }; @@ -755,14 +756,14 @@ static void *__dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, allowblock = gfpflags_allow_blocking(gfp); cma = allowblock ? dev_get_cma_area(dev) : false; - if (cma) + if (!allowblock && !is_coherent && want_vaddr) + buf->allocator = &pool_allocator; + else if (cma) buf->allocator = &cma_allocator; else if (is_coherent) buf->allocator = &simple_allocator; - else if (allowblock) - buf->allocator = &remap_allocator; else - buf->allocator = &pool_allocator; + buf->allocator = &remap_allocator; addr = buf->allocator->alloc(&args, &page); -- 2.20.1 _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu