From patchwork Fri Jun 14 14:44:26 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 1116044 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.infradead.org (client-ip=2607:7c80:54:e::133; helo=bombadil.infradead.org; envelope-from=linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="qeQIGSLL"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 45QNgp21nYz9sBp for ; Sat, 15 Jun 2019 00:45:26 +1000 (AEST) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=jR2pwHVsRstFXMaco11E+qxH37lkgztyixNJmbbYapE=; b=qeQIGSLLuQ4SOG EKyyWNN/8mFarrPRaG1io7IiOykWGcuT2CeqK1ZXnWn0+uErPOdeEzQ1UxROlZRzXSg2d5kHy4WqZ WmmRu2P/9YlXPS7ZhFFDtZLDbca5FcIz06BUNIBNZtLtk613Ty23Oq1WbgicLq/nRavFKvVBPt6f3 JcfRNbBIOv9FotVYjXVrtSGomYTh7xQfKDaWbArtXaPftJYeu8wraDmhfALcbsIpM/R/f7pjnjhtu bt6Vk4VDKRFUa7utJDT6M2rbGqrrofSFIfMXc8PjZwgOXbnNBIo3HN+5SHShTtZUWbSfdbhGoZRUv Jtq+NzNxnIgAueTEEs1g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hbnSE-0007bU-AG; Fri, 14 Jun 2019 14:45:22 +0000 Received: from 213-225-9-13.nat.highway.a1.net ([213.225.9.13] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92 #3 (Red Hat Linux)) id 1hbnRb-0005pn-PS; Fri, 14 Jun 2019 14:44:44 +0000 From: Christoph Hellwig To: Vineet Gupta Subject: [PATCH 2/7] arc: remove the partial DMA_ATTR_NON_CONSISTENT support Date: Fri, 14 Jun 2019 16:44:26 +0200 Message-Id: <20190614144431.21760-3-hch@lst.de> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190614144431.21760-1-hch@lst.de> References: <20190614144431.21760-1-hch@lst.de> MIME-Version: 1.0 X-BeenThere: linux-snps-arc@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on Synopsys ARC Processors List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jonas Bonn , linux-xtensa@linux-xtensa.org, Vladimir Murzin , linux-parisc@vger.kernel.org, Helge Deller , linux-kernel@vger.kernel.org, Stefan Kristiansson , iommu@lists.linux-foundation.org, openrisc@lists.librecores.org, Stafford Horne , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org The arc DMA code supports DMA_ATTR_NON_CONSISTENT allocations, but does not provide a cache_sync operation. This means any user of it will never be able to actually transfer cache ownership and thus cause coherency bugs. Signed-off-by: Christoph Hellwig --- arch/arc/mm/dma.c | 21 ++++++--------------- 1 file changed, 6 insertions(+), 15 deletions(-) diff --git a/arch/arc/mm/dma.c b/arch/arc/mm/dma.c index 1525ac00fd02..9832928f896d 100644 --- a/arch/arc/mm/dma.c +++ b/arch/arc/mm/dma.c @@ -24,7 +24,6 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, struct page *page; phys_addr_t paddr; void *kvaddr; - bool need_coh = !(attrs & DMA_ATTR_NON_CONSISTENT); /* * __GFP_HIGHMEM flag is cleared by upper layer functions @@ -46,14 +45,10 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, * A coherent buffer needs MMU mapping to enforce non-cachability. * kvaddr is kernel Virtual address (0x7000_0000 based). */ - if (need_coh) { - kvaddr = ioremap_nocache(paddr, size); - if (kvaddr == NULL) { - __free_pages(page, order); - return NULL; - } - } else { - kvaddr = (void *)(u32)paddr; + kvaddr = ioremap_nocache(paddr, size); + if (kvaddr == NULL) { + __free_pages(page, order); + return NULL; } /* @@ -66,9 +61,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, * Currently flush_cache_vmap nukes the L1 cache completely which * will be optimized as a separate commit */ - if (need_coh) - dma_cache_wback_inv(paddr, size); - + dma_cache_wback_inv(paddr, size); return kvaddr; } @@ -78,9 +71,7 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr, phys_addr_t paddr = dma_handle; struct page *page = virt_to_page(paddr); - if (!(attrs & DMA_ATTR_NON_CONSISTENT)) - iounmap((void __force __iomem *)vaddr); - + iounmap((void __force __iomem *)vaddr); __free_pages(page, get_order(size)); }