From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anshuman Khandual Subject: Re: [PATCH 11/12] swiotlb: move the SWIOTLB config symbol to lib/Kconfig Date: Tue, 17 Apr 2018 11:40:36 +0530 Message-ID: <1c4007b5-c0d4-7077-b2c1-767c6abbf79f@linux.vnet.ibm.com> References: <20180415145947.1248-1-hch@lst.de> <20180415145947.1248-12-hch@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20180415145947.1248-12-hch-jcswGhMUV9g@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: iommu-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Christoph Hellwig , Konrad Rzeszutek Wilk , iommu-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Cc: linux-mips-6z/3iImG2C8G8FEW9MqTrA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-pci-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ide-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, sparclinux-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: linux-ide@vger.kernel.org On 04/15/2018 08:29 PM, Christoph Hellwig wrote: > This way we have one central definition of it, and user can select it as > needed. Note that we also add a second ARCH_HAS_SWIOTLB symbol to > indicate the architecture supports swiotlb at all, so that we can still > make the usage optional for a few architectures that want this feature > to be user selectable. > > Signed-off-by: Christoph Hellwig snip > + > +config SWIOTLB > + bool "SWIOTLB support" > + default ARCH_HAS_SWIOTLB > + select DMA_DIRECT_OPS > + select NEED_DMA_MAP_STATE > + select NEED_SG_DMA_LENGTH > + ---help--- > + Support for IO bounce buffering for systems without an IOMMU. > + This allows us to DMA to the full physical address space on > + platforms where the size of a physical address is larger > + than the bus address. If unsure, say Y. > + > config CHECK_SIGNATURE > bool Pulling DMA_DIRECT_OPS config option by default when SWIOTLB is enabled makes sense. This option was also needed to be enabled separately even to use swiotlb_dma_ops.