From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43787) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eRfcN-0003E8-Br for qemu-devel@nongnu.org; Wed, 20 Dec 2017 09:45:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eRfcM-0006Oa-H9 for qemu-devel@nongnu.org; Wed, 20 Dec 2017 09:45:11 -0500 Received: from mx1.redhat.com ([209.132.183.28]:44338) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1eRfcM-0006MU-Ai for qemu-devel@nongnu.org; Wed, 20 Dec 2017 09:45:10 -0500 References: <20171217125457.3429-1-marcel@redhat.com> <20171217125457.3429-4-marcel@redhat.com> <20171219194739-mutt-send-email-mst@kernel.org> From: Marcel Apfelbaum Message-ID: <283b99aa-7036-6cfd-17f8-b82fe65982db@redhat.com> Date: Wed, 20 Dec 2017 16:45:06 +0200 MIME-Version: 1.0 In-Reply-To: <20171219194739-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH V2 3/5] docs: add pvrdma device documentation List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: qemu-devel@nongnu.org, ehabkost@redhat.com, imammedo@redhat.com, yuval.shaia@oracle.com, pbonzini@redhat.com On 19/12/2017 19:47, Michael S. Tsirkin wrote: > On Sun, Dec 17, 2017 at 02:54:55PM +0200, Marcel Apfelbaum wrote: >> Signed-off-by: Marcel Apfelbaum >> Signed-off-by: Yuval Shaia >> --- >> docs/pvrdma.txt | 145 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 145 insertions(+) >> create mode 100644 docs/pvrdma.txt >> >> diff --git a/docs/pvrdma.txt b/docs/pvrdma.txt >> new file mode 100644 >> index 0000000000..74c5cf2495 >> --- /dev/null >> +++ b/docs/pvrdma.txt >> @@ -0,0 +1,145 @@ >> +Paravirtualized RDMA Device (PVRDMA) >> +==================================== >> + [...] >> + >> +4. Implementation details >> +========================= >> +The device acts like a proxy between the Guest Driver and the host >> +ibdevice interface. >> +On configuration path: >> + - For every hardware resource request (PD/QP/CQ/...) the pvrdma will request >> + a resource from the backend interface, maintaining a 1-1 mapping >> + between the guest and host. >> +On data path: >> + - Every post_send/receive received from the guest will be converted into >> + a post_send/receive for the backend. The buffers data will not be touched >> + or copied resulting in near bare-metal performance for large enough buffers. >> + - Completions from the backend interface will result in completions for >> + the pvrdma device. > Hi Michael, > > Where's the host/guest interface documented? > It is the VMware PVRDMA spec, I am not sure is publicly available, we kind of reverse-engineered it. We will add some info from the linked presentation on the PCI BARs and how are they used. Thanks, Marcel >> + >> + [...]