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 184C7C433FE for ; Wed, 22 Dec 2021 13:47:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236698AbhLVNrE (ORCPT ); Wed, 22 Dec 2021 08:47:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234159AbhLVNrD (ORCPT ); Wed, 22 Dec 2021 08:47:03 -0500 Received: from mail-wm1-x32d.google.com (mail-wm1-x32d.google.com [IPv6:2a00:1450:4864:20::32d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EE814C061574; Wed, 22 Dec 2021 05:47:02 -0800 (PST) Received: by mail-wm1-x32d.google.com with SMTP id i12so1626094wmq.4; Wed, 22 Dec 2021 05:47:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=wxvMlF+l51oDklf4EWdV5hXzMGWV02iTMeiu5UDuE14=; b=EqwnjVMY7HMk9vmwXPlECKQbKBxQ1TmHzuOg9dZYm38j3qn958X3+M1Lsm73knrJN8 gPqRxOj/t/X0hnbQrQzvxwDlOtOIzRn0NsHQF2cOMikt6I1aybrCWrJRNUc91wW/Ruer R0q17uz4oBfLyWR3W9I95XBcT0sHWigqYiMC+GPmCVawoSUXJdA7OxboIlEeR1eDkxkt AuXbjq8h3m4jsheXsDmFu5j5B0Hf1WGZl5L5R5e9xRQ4SFAWKgHTKw+eq29tyN+31iqK BjpSCDJoTc5rCPfgMtSAe9oOfiokMXuNKCCxINdNM1QAYxFepXoZogVo7koypWnJNx0D jykQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=wxvMlF+l51oDklf4EWdV5hXzMGWV02iTMeiu5UDuE14=; b=mZ7BbpdSngvs++yy0UM6bA0DxBeiSAod1SL6uqe7KZZxyd9NK7acggYj+rVHpi6l0M vt2o48vzPN4tm4jLEOq55mX+Syy3RHQKjJnCHS+isdTaUjOZhKvqqeVHf377z8E8kH1r uKwS1rrXEmQNNtX2IZayCj7ec8qCHJxvnpgGDNcaXaz5bm6tYpYuvtq2Oyf5mHTfsi2h MjxkWlH3tTbZdWiweYAvDKh87Mb4Bn8HsybjX43oCZgtd3varbFWpGVcbXXG0dRFop9T eafk1JFIC2+BexbqVD5ODlZaRJWDVy8udEkLL4us51hOihy8d2FSXPAl5Rxi53sqj6OH fjyA== X-Gm-Message-State: AOAM531PoJqjtM4kNmRQGo2HijbgauWqbmn2YzpZ4l+6v3QsA27DA4c2 i5P9n/H1utMxNgrkH/5UkOAPc0BgHSB6C31MqBg= X-Google-Smtp-Source: ABdhPJxkxIwRoqvckjEUCYcJLdJLYPj3QuiYAWIBmMn64kvOBURss2n9lxMGdsbdDXeake/d5KlX0U843vkNazgqp0c= X-Received: by 2002:a1c:f213:: with SMTP id s19mr1042698wmc.0.1640180821187; Wed, 22 Dec 2021 05:47:01 -0800 (PST) MIME-Version: 1.0 References: <2da62822fd56414d9893b89e160ed05c@kioxia.com> In-Reply-To: <2da62822fd56414d9893b89e160ed05c@kioxia.com> From: Kanchan Joshi Date: Wed, 22 Dec 2021 19:16:35 +0530 Message-ID: Subject: Re: [RFC 02/13] nvme: wire-up support for async-passthru on To: Clay Mayers Cc: "linux-nvme@lists.infradead.org" , "io-uring@vger.kernel.org" , "linux-block@vger.kernel.org" , "axboe@kernel.dk" , "hch@lst.de" , "kbusch@kernel.org" , "javier@javigon.com" , "anuj20.g@samsung.com" , "pankydev8@gmail.com" Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Wed, Dec 22, 2021 at 2:46 AM Clay Mayers wrote: > > Message-ID: <20211220141734.12206-3-joshi.k@samsung.com> > > On 12/20/21 19:47:23 +0530, Kanchan Joshi wrote: > > Introduce handlers for fops->async_cmd(), implementing async passthru on > > char device (including the multipath one). > > The handlers supports NVME_IOCTL_IO64_CMD. > > > I commented on these two issues below in more detail at > https://github.com/joshkan/nvme-uring-pt/issues That is on general/existing nvme ioctl (and not specific to this series). You might want to open up a discussion in the nvme mailing list. > > +static void nvme_setup_uring_cmd_data(struct request *rq, > > + struct io_uring_cmd *ioucmd, void *meta, > > + void __user *meta_buffer, u32 meta_len, bool write) { > > + struct nvme_uring_cmd *cmd = nvme_uring_cmd(ioucmd); > > + > > + /* to free bio on completion, as req->bio will be null at that time */ > > + cmd->bio = rq->bio; > > + /* meta update is required only for read requests */ > > + if (meta && !write) { > > + cmd->meta = meta; > > + cmd->meta_buffer = meta_buffer; > > + cmd->meta_len = meta_len; > > + } else { > > + cmd->meta = NULL; > I believe that not saving meta in cmd->meta will leak it when it's a write. Indeed. Will fix that up. > But nvme_pt_task_cb also needs to change to copy to user when > cmd->meta_buffer is set instead of cmd->meta. > > > + > > +int nvme_ns_chr_async_cmd(struct io_uring_cmd *ioucmd, > > + enum io_uring_cmd_flags flags) > > +{ > > + struct nvme_ns *ns = container_of(file_inode(ioucmd->file)->i_cdev, > > + struct nvme_ns, cdev); > > + > > + return nvme_ns_async_ioctl(ns, ioucmd); } > > + > The uring cmd flags are not being passed to nvme_ns_async_ioctl - what if > IO_URING_F_NONBLOCK Is set? When it is, I think the nvme_alloc_request() > call in nvme_submit_user_cmd() needs to pass in BLK_MQ_REQ_NOWAIT as > the flags parameter or move to another thread. Our proto-type does the former > requiring user mode to retry on -EWOULDBLOCK and -EBUSY. Right, this part is not handled. Need to get that sorted in the next version. Thanks. -- Joshi