From patchwork Thu Jul 28 12:39:15 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ziyang Zhang X-Patchwork-Id: 12931240 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 54265C19F29 for ; Thu, 28 Jul 2022 12:39:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238111AbiG1Mjp (ORCPT ); Thu, 28 Jul 2022 08:39:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236413AbiG1Mjn (ORCPT ); Thu, 28 Jul 2022 08:39:43 -0400 Received: from out30-44.freemail.mail.aliyun.com (out30-44.freemail.mail.aliyun.com [115.124.30.44]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 51CAF6BD64 for ; Thu, 28 Jul 2022 05:39:42 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R451e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046050;MF=ziyangzhang@linux.alibaba.com;NM=1;PH=DS;RN=5;SR=0;TI=SMTPD_---0VKfiKRc_1659011979; Received: from localhost.localdomain(mailfrom:ZiyangZhang@linux.alibaba.com fp:SMTPD_---0VKfiKRc_1659011979) by smtp.aliyun-inc.com; Thu, 28 Jul 2022 20:39:39 +0800 From: ZiyangZhang To: axboe@kernel.dk, ming.lei@redhat.com Cc: ZiyangZhang@linux.alibaba.com, linux-block@vger.kernel.org, xiaoguang.wang@linux.alibaba.com Subject: [PATCH V4 1/2] ublk_cmd.h: add one new ublk command: UBLK_IO_NEED_GET_DATA Date: Thu, 28 Jul 2022 20:39:15 +0800 Message-Id: X-Mailer: git-send-email 2.34.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Add one new ublk command: UBLK_IO_NEED_GET_DATA. It is prepared for a new feature designed for a user application who wants to allocate IO buffer and set IO buffer address only after it receives an IO request from ublksrv. Reviewed-by: Ming Lei Signed-off-by: ZiyangZhang --- include/uapi/linux/ublk_cmd.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h index ca33092354ab..51a1ef9051ab 100644 --- a/include/uapi/linux/ublk_cmd.h +++ b/include/uapi/linux/ublk_cmd.h @@ -28,12 +28,21 @@ * this IO request, request's handling result is committed to ublk * driver, meantime FETCH_REQ is piggyback, and FETCH_REQ has to be * handled before completing io request. + * + * NEED_GET_DATA: only used for write requests to set io addr and copy data + * When NEED_GET_DATA is set, ublksrv has to issue UBLK_IO_NEED_GET_DATA + * command after ublk driver returns UBLK_IO_RES_NEED_GET_DATA. + * + * It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag + * while starting a ublk device. */ #define UBLK_IO_FETCH_REQ 0x20 #define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21 +#define UBLK_IO_NEED_GET_DATA 0x22 /* only ABORT means that no re-fetch */ #define UBLK_IO_RES_OK 0 +#define UBLK_IO_RES_NEED_GET_DATA 1 #define UBLK_IO_RES_ABORT (-ENODEV) #define UBLKSRV_CMD_BUF_OFFSET 0 @@ -54,6 +63,15 @@ */ #define UBLK_F_URING_CMD_COMP_IN_TASK (1ULL << 1) +/* + * User should issue io cmd again for write requests to + * set io buffer address and copy data from bio vectors + * to the userspace io buffer. + * + * In this mode, task_work is not used. + */ +#define UBLK_F_NEED_GET_DATA (1UL << 2) + /* device state */ #define UBLK_S_DEV_DEAD 0 #define UBLK_S_DEV_LIVE 1