From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Thu, 27 Sep 2018 11:10:13 -0600 From: Keith Busch To: Logan Gunthorpe Cc: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-nvme@lists.infradead.org, linux-rdma@vger.kernel.org, linux-nvdimm@lists.01.org, linux-block@vger.kernel.org, Jens Axboe , Christian =?iso-8859-1?Q?K=F6nig?= , Benjamin Herrenschmidt , Alex Williamson , =?iso-8859-1?B?Suly9G1l?= Glisse , Jason Gunthorpe , Bjorn Helgaas , Max Gurtovoy , Christoph Hellwig Subject: Re: [PATCH v8 09/13] nvme-pci: Use PCI p2pmem subsystem to manage the CMB Message-ID: <20180927171013.GC19589@localhost.localdomain> References: <20180927165420.5290-1-logang@deltatee.com> <20180927165420.5290-10-logang@deltatee.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20180927165420.5290-10-logang@deltatee.com> List-ID: On Thu, Sep 27, 2018 at 10:54:16AM -0600, Logan Gunthorpe wrote: > Register the CMB buffer as p2pmem and use the appropriate allocation > functions to create and destroy the IO submission queues. > > If the CMB supports WDS and RDS, publish it for use as P2P memory > by other devices. > > Kernels without CONFIG_PCI_P2PDMA will also no longer support NVMe CMB. > However, seeing the main use-cases for the CMB is P2P operations, > this seems like a reasonable dependency. > > We drop the __iomem safety on the buffer seeing that, by convention, it's > safe to directly access memory mapped by memremap()/devm_memremap_pages(). > Architectures where this is not safe will not be supported by memremap() > and therefore will not be support PCI P2P and have no support for CMB. > > Signed-off-by: Logan Gunthorpe Looks good to me. Reviewed-by: Keith Busch