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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C3D9CC433F5 for ; Sun, 13 Mar 2022 21:53:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233679AbiCMVyu (ORCPT ); Sun, 13 Mar 2022 17:54:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34098 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231156AbiCMVyt (ORCPT ); Sun, 13 Mar 2022 17:54:49 -0400 Received: from mail-ej1-f49.google.com (mail-ej1-f49.google.com [209.85.218.49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4DA5B15A10; Sun, 13 Mar 2022 14:53:41 -0700 (PDT) Received: by mail-ej1-f49.google.com with SMTP id r13so30080277ejd.5; Sun, 13 Mar 2022 14:53:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=GhvMlaLXIBl69d2e2I1DBwNJZfAkADFlzhCg7cXuE7k=; b=xT+6CZydUyXijY4NFZ9DRytUZo0z1IGpqYev9Pj8Fi+PcOMVpkbby4+2KjOR84qqXS 8n2AmNX5Du8M7s+P3JTgHHRuGF0/08St/iVyuie22ERNKpxa6eYfGRrs/Qsa/m2ZT3nI nW3zxLtEA1rUybxfYqB3yCZ6P6DyjrRTOYprg4o9Oo6Krcy6otqMigWBGwACenLJHyJh z8noWqHXuB7yIbiw9KHAXNrPTCEEsQpVvV8BQtz3QxzT58FJqRdjG9QNCN3ovIywpkv1 twMkkgEKK4p/jkyUcSJwoFJSynsLxQs6wK6eIA4pvHVHyfc/P808I3JT0a1UQ+yBZbfp Bk0w== X-Gm-Message-State: AOAM530cr8efXgywVbiCno2XJjfCV7ew/yJgBC/v8baTkpD6fQ3IL0js kAqPtCtgUh1XRyuR6UdMSCg= X-Google-Smtp-Source: ABdhPJxed+q6AT46dUxx+14XZWsrYC4Q4t/biXHM77QpXqFMCGdDrmRX1buo2MOHsW3KyPhpW3Z1qQ== X-Received: by 2002:a17:906:2695:b0:6cf:e1b4:118b with SMTP id t21-20020a170906269500b006cfe1b4118bmr16156282ejc.348.1647208419888; Sun, 13 Mar 2022 14:53:39 -0700 (PDT) Received: from [10.100.102.14] (46-117-116-119.bb.netvision.net.il. [46.117.116.119]) by smtp.gmail.com with ESMTPSA id q16-20020a170906145000b006bdaf981589sm5997845ejc.81.2022.03.13.14.53.37 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 13 Mar 2022 14:53:39 -0700 (PDT) Message-ID: <7a123895-1102-4b36-2d6e-1e00e978d03d@grimberg.me> Date: Sun, 13 Mar 2022 23:53:37 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH 05/17] nvme: wire-up support for async-passthru on char-device. Content-Language: en-US To: Kanchan Joshi , axboe@kernel.dk, hch@lst.de, kbusch@kernel.org, asml.silence@gmail.com Cc: io-uring@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, sbates@raithlin.com, logang@deltatee.com, pankydev8@gmail.com, javier@javigon.com, mcgrof@kernel.org, a.manzanares@samsung.com, joshiiitr@gmail.com, anuj20.g@samsung.com References: <20220308152105.309618-1-joshi.k@samsung.com> <20220308152105.309618-6-joshi.k@samsung.com> From: Sagi Grimberg In-Reply-To: <20220308152105.309618-6-joshi.k@samsung.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org > +int nvme_ns_head_chr_async_cmd(struct io_uring_cmd *ioucmd) > +{ > + struct cdev *cdev = file_inode(ioucmd->file)->i_cdev; > + struct nvme_ns_head *head = container_of(cdev, struct nvme_ns_head, cdev); > + int srcu_idx = srcu_read_lock(&head->srcu); > + struct nvme_ns *ns = nvme_find_path(head); > + int ret = -EWOULDBLOCK; > + > + if (ns) > + ret = nvme_ns_async_ioctl(ns, ioucmd); > + srcu_read_unlock(&head->srcu, srcu_idx); > + return ret; > +} No one cares that this has no multipathing capabilities what-so-ever? despite being issued on the mpath device node? I know we are not doing multipathing for userspace today, but this feels like an alternative I/O interface for nvme, seems a bit cripled with zero multipathing capabilities...