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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 48E8BC6FA82 for ; Fri, 23 Sep 2022 15:40:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ZiGSfOuqjgKOkE0d4Nz0aG6n0kWFrbNrtEAma4LspFw=; b=S61+eOBEqwMbsrhGqYwWNfmWZ2 a1gQWmjLm804doFHXNv4GmiyxyKNLtfBsPezD2BxBdKYIIxxK5khFumfmfoaRk8I8e6Iy01IdYFZi 9eKqqZB35e7HOvuoj6hm1TUowwWaE0lEa7Ap7AprpjehnKrb0g5IbZym26wXZ+E/Tk8H+CRq9f0Gt PM0As63hFC1gsoJ6zFxrTAfNURoxYa9Gwb038QodcIdwbYkylccTgGmro7WQIowuVjGdMpSfzYBqh COFMBXT0NTT4UAHNGMEQccIj5sQlTMeUKBqUJP9ZTvebb0VfpBYpgATDjB0D0ikymVeVEtXqoZypu kOb91dLQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1obknI-004qYx-Nk; Fri, 23 Sep 2022 15:40:48 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1obknF-004qVs-PT for linux-nvme@lists.infradead.org; Fri, 23 Sep 2022 15:40:47 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 4425467373; Fri, 23 Sep 2022 17:40:42 +0200 (CEST) Date: Fri, 23 Sep 2022 17:40:41 +0200 From: Christoph Hellwig To: Kanchan Joshi Cc: axboe@kernel.dk, hch@lst.de, kbusch@kernel.org, io-uring@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, gost.dev@samsung.com Subject: Re: [PATCH for-next v8 5/5] nvme: wire up fixed buffer support for nvme passthrough Message-ID: <20220923154041.GD21275@lst.de> References: <20220923092854.5116-1-joshi.k@samsung.com> <20220923092854.5116-6-joshi.k@samsung.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220923092854.5116-6-joshi.k@samsung.com> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220923_084045_983979_6AF2476E X-CRM114-Status: GOOD ( 12.57 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Fri, Sep 23, 2022 at 02:58:54PM +0530, Kanchan Joshi wrote: > if (!vec) > + if (!fixedbufs) > + ret = blk_rq_map_user(q, req, NULL, > + nvme_to_user_ptr(ubuffer), bufflen, > + GFP_KERNEL); > + else { > + struct iov_iter iter; > + > + ret = io_uring_cmd_import_fixed(ubuffer, bufflen, > + rq_data_dir(req), &iter, ioucmd); > + if (ret < 0) > + goto out; > + ret = blk_rq_map_user_bvec(req, &iter); > + } Given that the fixedufs case doesn't handle the vec case we can do with some untangling and a single level of indentation here. Even with that a WARN_ON_ONCE() for that impossible case would be good to have, though.