From patchwork Mon Jun 29 13:03:56 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 216929 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=-9.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, 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 69A10C433E0 for ; Mon, 29 Jun 2020 19:09:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4AAE1206E9 for ; Mon, 29 Jun 2020 19:09:05 +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="aJrw9aNz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730515AbgF2TIu (ORCPT ); Mon, 29 Jun 2020 15:08:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41716 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730507AbgF2TCm (ORCPT ); Mon, 29 Jun 2020 15:02:42 -0400 Received: from casper.infradead.org (unknown [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8FE5DC02A553; Mon, 29 Jun 2020 06:04:23 -0700 (PDT) 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=PsN3qRjrSOLsKgEY3b9oohxHLZWrJFcsvZsnix+thqM=; b=aJrw9aNzBqPIJz75MBYlfnCGSr ToiXcesL50+YEb9Ecs4HWaP59LlBbTh8rBnY1rZxyrNZzJl7uQufB9JBBjqGU4iZM1Pez3hKqdgBW +UopSMXHKslG7KrOMT9vokf0Q7L4gsUQ14apX0DqwBud4wWRakM9z4vfTtPoBqPcYah1ba9HLCDnh 85O4HVeR+n+y/ihCRcqxQvqex0BWz/+LxlZ3uJMnA8QZo4lX0UsTuL4NrLOziPv9MWa1wAMY2kQF4 9ZTsjYCnH5pgJdEw+FUCDMRXANsZufwUUpeEx+foby4/7Cl669c8FJ4DZ+71gaCzwF5MEBbmDxswR 8JRlJpWQ==; Received: from [2001:4bb8:184:76e3:c71:f334:376b:cf5f] (helo=localhost) by casper.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jptS7-0004XB-2A; Mon, 29 Jun 2020 13:04:03 +0000 From: Christoph Hellwig To: =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= Cc: Magnus Karlsson , Jonathan Lemon , iommu@lists.linux-foundation.org, netdev@vger.kernel.org, bpf@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/4] dma-mapping: add a new dma_need_sync API Date: Mon, 29 Jun 2020 15:03:56 +0200 Message-Id: <20200629130359.2690853-2-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200629130359.2690853-1-hch@lst.de> References: <20200629130359.2690853-1-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 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Add a new API to check if calls to dma_sync_single_for_{device,cpu} are required for a given DMA streaming mapping. Signed-off-by: Christoph Hellwig --- Documentation/core-api/dma-api.rst | 8 ++++++++ include/linux/dma-direct.h | 1 + include/linux/dma-mapping.h | 5 +++++ kernel/dma/direct.c | 6 ++++++ kernel/dma/mapping.c | 10 ++++++++++ 5 files changed, 30 insertions(+) diff --git a/Documentation/core-api/dma-api.rst b/Documentation/core-api/dma-api.rst index 2d8d2fed731720..f41620439ef349 100644 --- a/Documentation/core-api/dma-api.rst +++ b/Documentation/core-api/dma-api.rst @@ -204,6 +204,14 @@ Returns the maximum size of a mapping for the device. The size parameter of the mapping functions like dma_map_single(), dma_map_page() and others should not be larger than the returned value. +:: + + bool + dma_need_sync(struct device *dev, dma_addr_t dma_addr); + +Returns %true if dma_sync_single_for_{device,cpu} calls are required to +transfer memory ownership. Returns %false if those calls can be skipped. + :: unsigned long diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h index cdfa400f89b3d3..5184735a0fe8eb 100644 --- a/include/linux/dma-direct.h +++ b/include/linux/dma-direct.h @@ -85,4 +85,5 @@ int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, dma_addr_t dma_addr, size_t size, unsigned long attrs); int dma_direct_supported(struct device *dev, u64 mask); +bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr); #endif /* _LINUX_DMA_DIRECT_H */ diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 78f677cf45ab69..a33ed3954ed465 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -461,6 +461,7 @@ int dma_set_mask(struct device *dev, u64 mask); int dma_set_coherent_mask(struct device *dev, u64 mask); u64 dma_get_required_mask(struct device *dev); size_t dma_max_mapping_size(struct device *dev); +bool dma_need_sync(struct device *dev, dma_addr_t dma_addr); unsigned long dma_get_merge_boundary(struct device *dev); #else /* CONFIG_HAS_DMA */ static inline dma_addr_t dma_map_page_attrs(struct device *dev, @@ -571,6 +572,10 @@ static inline size_t dma_max_mapping_size(struct device *dev) { return 0; } +static inline bool dma_need_sync(struct device *dev, dma_addr_t dma_addr) +{ + return false; +} static inline unsigned long dma_get_merge_boundary(struct device *dev) { return 0; diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 93f578a8e613ba..95866b64758100 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -539,3 +539,9 @@ size_t dma_direct_max_mapping_size(struct device *dev) return swiotlb_max_mapping_size(dev); return SIZE_MAX; } + +bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr) +{ + return !dev_is_dma_coherent(dev) || + is_swiotlb_buffer(dma_to_phys(dev, dma_addr)); +} diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 98e3d873792ea4..a8c18c9a796fdc 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -397,6 +397,16 @@ size_t dma_max_mapping_size(struct device *dev) } EXPORT_SYMBOL_GPL(dma_max_mapping_size); +bool dma_need_sync(struct device *dev, dma_addr_t dma_addr) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (dma_is_direct(ops)) + return dma_direct_need_sync(dev, dma_addr); + return ops->sync_single_for_cpu || ops->sync_single_for_device; +} +EXPORT_SYMBOL_GPL(dma_need_sync); + unsigned long dma_get_merge_boundary(struct device *dev) { const struct dma_map_ops *ops = get_dma_ops(dev);