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[209.132.180.67]) by mx.google.com with ESMTP id v77si3225656pfa.108.2018.03.14.21.32.10; Wed, 14 Mar 2018 21:32:36 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@intel-com.20150623.gappssmtp.com header.s=20150623 header.b=U4N1paGL; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751405AbeCOEap (ORCPT + 99 others); Thu, 15 Mar 2018 00:30:45 -0400 Received: from mail-oi0-f52.google.com ([209.85.218.52]:44274 "EHLO mail-oi0-f52.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750731AbeCOEam (ORCPT ); Thu, 15 Mar 2018 00:30:42 -0400 Received: by mail-oi0-f52.google.com with SMTP id b8so4616081oib.11 for ; Wed, 14 Mar 2018 21:30:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel-com.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=cZDUlayCXD97e+2yzOXMaxAD3RIUNnnvnDgClDNBZI8=; b=U4N1paGL9WC+5BJ87bjtlKocXrSWXckEON5WCmUciPquTJPa/nPov2cyiNHkQhyuqq WRUn/7/s35wtjFijRw1JSYxNdx5wMZY/zGpwkEJm5H4KyqwyIh/qGSL+ZL/Jg9T0MKqO UVKF6uJWyyuMlQYh2oanUThCFgVO4DiujcvoKRQWfvjsiyEnTY/qUYSnDLbbD7vqhXPG NWvd64c7zHT3PNSpXdz8lMq/vkyJ/JrjvcrcYoc3HQqB9Q8icAe2pE3SKpqJHGsU4HQn gVqNOzzP0lkE+ViK+LGEcpyiAUF4abgYDw7K2RDB4Z8Gtg9CRwPlgQwsiQHGjPTz/1vi 2Ecg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=cZDUlayCXD97e+2yzOXMaxAD3RIUNnnvnDgClDNBZI8=; b=UmtiJ5DCPl8KvlHHPgUTXpuPnEOO1dUaTg2CkCnn3//cjVd5c9WJWUEe8YBQTU8aPq 7fcwkSbTLmxSPZO7e9ljrzKvhMXaHfq/aw3Swm361VQyUQo88g1eCNMlfNLfkJcUIXjs bw6dYCCq7pT9O7UzRJNugcXxXllkIV320f8eFixXZbGPmeJCZKeFjiFToggVbYzgTyu8 xQKBP3OWENePfjPqkb7vKlAlfCYaRA+2YoICCywsPuxt5ECy1xv5RAWQDm+DX12b1xWg 39m6e3R/WfvPhxYT2J7Xq5xh+MEU5iScu7jRASFmWzIRI0gGswSzDDMk1zBV2RTWX5Pe HeZg== X-Gm-Message-State: AElRT7FNwrcmh1HoNIUFPtAbUkwKMC2QSRXbnQVfQHIHOU0MxPhF5fCZ GX5o2EJ57s/N/n4nXpiwT6rNeSWEjIBPZstaADWcbg== X-Received: by 10.202.27.1 with SMTP id b1mr4518034oib.110.1521088242302; Wed, 14 Mar 2018 21:30:42 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:a9d:5189:0:0:0:0:0 with HTTP; Wed, 14 Mar 2018 21:30:41 -0700 (PDT) In-Reply-To: References: <3ea80992-a0fc-08f2-d93d-ae0ec4e3f4ce@codeaurora.org> <4eb6850c-df1b-fd44-3ee0-d43a50270b53@deltatee.com> <757fca36-dee4-e070-669e-f2788bd78e41@codeaurora.org> <4f761f55-4e9a-dccb-d12f-c59d2cd689db@deltatee.com> <20180313230850.GA45763@bhelgaas-glaptop.roam.corp.google.com> <8de5d3dd-a78f-02d5-0eea-4365364143b6@deltatee.com> <20180314025639.GA50067@bhelgaas-glaptop.roam.corp.google.com> <112493af-ccd0-455b-6600-b50764f7ab7e@deltatee.com> <20180314185159.GD179719@bhelgaas-glaptop.roam.corp.google.com> From: Dan Williams Date: Wed, 14 Mar 2018 21:30:41 -0700 Message-ID: Subject: Re: [PATCH v3 01/11] PCI/P2PDMA: Support peer-to-peer memory To: Stephen Bates Cc: Logan Gunthorpe , Bjorn Helgaas , Sinan Kaya , "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" , Christoph Hellwig , Jens Axboe , Keith Busch , Sagi Grimberg , Bjorn Helgaas , Jason Gunthorpe , Max Gurtovoy , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Benjamin Herrenschmidt , Alex Williamson Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Mar 14, 2018 at 12:34 PM, Stephen Bates wrote: >> P2P over PCI/PCI-X is quite common in devices like raid controllers. > > Hi Dan > > Do you mean between PCIe devices below the RAID controller? Isn't it pretty novel to be able to support PCIe EPs below a RAID controller (as opposed to SCSI based devices)? I'm thinking of the classic I/O offload card where there's an NTB to an internal PCI bus that has a storage controller and raid offload engines.