From mboxrd@z Thu Jan 1 00:00:00 1970 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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 8AAB4C3276F for ; Thu, 2 Jan 2020 22:43:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 68C5921835 for ; Thu, 2 Jan 2020 22:43:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730585AbgABWed (ORCPT ); Thu, 2 Jan 2020 17:34:33 -0500 Received: from mail-pg1-f195.google.com ([209.85.215.195]:45014 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730576AbgABWed (ORCPT ); Thu, 2 Jan 2020 17:34:33 -0500 Received: by mail-pg1-f195.google.com with SMTP id x7so22545627pgl.11; Thu, 02 Jan 2020 14:34:32 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=8mVvbAyQUW31vtCB7au92EGbYazy736+WkClVlaU2E0=; b=SkH84y9Kc6c1gxSiWpFkpNWuml4KFD3mC5SIXA3wzffzsTg2dx8fDVQaKwq/3ZsOJx Eba9sKAf7WjT+mphyWQKUEAgbp4Zq9AKkQVwchQjMbKxcWMWkt917ChcfsVR2fmTDA2s XdQgARIQf/n7mJ/YuBcIH6sSjzFriRkUJRP6HOvi4B2vCB/SobZ1nirgj0VT3HebEmsD dxc84USgLDybXj9HFwZi5yC/DK/6qJSVRsV0QK+tyTTkudsCj61mJoyueE8TPjTo08Wl FGHGYKq8l1hGJ65eoPeuxUXDafUFdVUpeaA+dT/xthqwpIf9RJlPsqOJ6JEcl9Xt61hX dVkw== X-Gm-Message-State: APjAAAUjXallXNuEeM3bDq3fiWWWSeZFqkstORZ62jMPtcNOHVdxzPVS l9VmjUegUIwe4hxIyD1buEM= X-Google-Smtp-Source: APXvYqzRXAPVdCIewiz9WFuQlrMZDrTyt9R+nWJ8bKFMmTlpu+xdIZnMCAjsyFlXH3I3x8W7+auR1g== X-Received: by 2002:a63:2bcd:: with SMTP id r196mr90058338pgr.65.1578004472447; Thu, 02 Jan 2020 14:34:32 -0800 (PST) Received: from desktop-bart.svl.corp.google.com ([2620:15c:2cd:202:4308:52a3:24b6:2c60]) by smtp.gmail.com with ESMTPSA id n1sm65339662pfd.47.2020.01.02.14.34.30 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 02 Jan 2020 14:34:31 -0800 (PST) Subject: Re: [PATCH v6 15/25] rnbd: private headers with rnbd protocol structs and helpers To: Jack Wang , linux-block@vger.kernel.org, linux-rdma@vger.kernel.org Cc: axboe@kernel.dk, hch@infradead.org, sagi@grimberg.me, leon@kernel.org, dledford@redhat.com, danil.kipnis@cloud.ionos.com, jinpu.wang@cloud.ionos.com, rpenyaev@suse.de References: <20191230102942.18395-1-jinpuwang@gmail.com> <20191230102942.18395-16-jinpuwang@gmail.com> From: Bart Van Assche Message-ID: Date: Thu, 2 Jan 2020 14:34:30 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.2 MIME-Version: 1.0 In-Reply-To: <20191230102942.18395-16-jinpuwang@gmail.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 12/30/19 2:29 AM, Jack Wang wrote: > + * @device_id: device_id on server side to identify the device Is this a number that only has a meaning inside the RTRS software? Is the role of this number perhaps similar to an NVMe namespace or SCSI LUN? If so, please mention this. Additionally, does this number start from zero or from one? > + * @max_segments: max segments hardware support in one transfer Which "hardware" does this comment refer to? The RDMA adapter or the block device in the server? In the latter case, what if the block device has been implemented in software? What kind of transfer does this comment refer to? A DMA transfer? If so, please mention this. > +struct rnbd_msg_open_rsp { > + struct rnbd_msg_hdr hdr; > + __le32 device_id; > + __le64 nsectors; > + __le32 max_hw_sectors; > + __le32 max_write_same_sectors; > + __le32 max_discard_sectors; > + __le32 discard_granularity; > + __le32 discard_alignment; > + __le16 physical_block_size; > + __le16 logical_block_size; > + __le16 max_segments; > + __le16 secure_discard; > + u8 rotational; > + u8 reserved[11]; > +}; Thanks, Bart.