From patchwork Wed Aug 31 15:51:33 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ziyang Zhang X-Patchwork-Id: 12960989 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 8C52FECAAD4 for ; Wed, 31 Aug 2022 15:54:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231377AbiHaPyX (ORCPT ); Wed, 31 Aug 2022 11:54:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37868 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232135AbiHaPyL (ORCPT ); Wed, 31 Aug 2022 11:54:11 -0400 Received: from out30-56.freemail.mail.aliyun.com (out30-56.freemail.mail.aliyun.com [115.124.30.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 57C24BCC24; Wed, 31 Aug 2022 08:54:05 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R361e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046056;MF=ziyangzhang@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0VNrdoBn_1661961229; Received: from localhost.localdomain(mailfrom:ZiyangZhang@linux.alibaba.com fp:SMTPD_---0VNrdoBn_1661961229) by smtp.aliyun-inc.com; Wed, 31 Aug 2022 23:54:02 +0800 From: ZiyangZhang To: ming.lei@redhat.com, axboe@kernel.dk Cc: xiaoguang.wang@linux.alibaba.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, joseph.qi@linux.alibaba.com, ZiyangZhang Subject: [RFC PATCH V2 3/6] ublk_drv: define macros for recovery feature and check them Date: Wed, 31 Aug 2022 23:51:33 +0800 Message-Id: <20220831155136.23434-4-ZiyangZhang@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20220831155136.23434-1-ZiyangZhang@linux.alibaba.com> References: <20220831155136.23434-1-ZiyangZhang@linux.alibaba.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org Define some macros for recovery feature. Especially define a new state: UBLK_S_DEV_RECOVERING which implies the ublk_device is recovering. UBLK_F_USER_RECOVERY implies that: (1) ublk_drv enables recovery feature. It won't let monitor_work to automatically abort rqs and release the device. Instead, it waits for user's START_USER_RECOVERY ctrl-cmd. (2) In monitor_work after a crash, ublk_drv ends(aborts) rqs issued to userspace(ublksrv) before crash. (3) In task work and ublk_queue_rq() after a crash, ublk_drv requeues rqs dispatched after crash. UBLK_F_USER_RECOVERY_REISSUE implies that: (1) everything UBLK_F_USER_RECOVERY implies except (2) ublk_drv requeues rqs issued to userspace(ublksrv) before crash. UBLK_F_USER_RECOVERY_REISSUE is designed for backends which: (1) tolerate double-writes because we may issue the same rq twice. (2) cannot let frontend users get I/O error, such as a RDONLY system. Signed-off-by: ZiyangZhang --- drivers/block/ublk_drv.c | 31 ++++++++++++++++++++++++++++++- include/uapi/linux/ublk_cmd.h | 7 +++++++ 2 files changed, 37 insertions(+), 1 deletion(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 0c6db0978ed0..0c3d32e8d686 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -49,7 +49,9 @@ /* All UBLK_F_* have to be included into UBLK_F_ALL */ #define UBLK_F_ALL (UBLK_F_SUPPORT_ZERO_COPY \ | UBLK_F_URING_CMD_COMP_IN_TASK \ - | UBLK_F_NEED_GET_DATA) + | UBLK_F_NEED_GET_DATA \ + | UBLK_F_USER_RECOVERY \ + | UBLK_F_USER_RECOVERY_REISSUE) /* All UBLK_PARAM_TYPE_* should be included here */ #define UBLK_PARAM_TYPE_ALL (UBLK_PARAM_TYPE_BASIC | UBLK_PARAM_TYPE_DISCARD) @@ -323,6 +325,33 @@ static inline int ublk_queue_cmd_buf_size(struct ublk_device *ub, int q_id) PAGE_SIZE); } +/* + * TODO: UBLK_F_USER_RECOVERY should be a flag for device, not for queue, + * since "some queues are aborted while others are recoverd" is really weird. + */ +static inline bool ublk_can_use_recovery(struct ublk_device *ub) +{ + struct ublk_queue *ubq = ublk_get_queue(ub, 0); + + if (ubq->flags & UBLK_F_USER_RECOVERY) + return true; + return false; +} + +/* + * TODO: UBLK_F_USER_RECOVERY_REISSUE should be a flag for device, not for queue, + * since "some queues are aborted while others are recoverd" is really weird. + */ +static inline bool ublk_can_use_recovery_reissue(struct ublk_device *ub) +{ + struct ublk_queue *ubq = ublk_get_queue(ub, 0); + + if ((ubq->flags & UBLK_F_USER_RECOVERY) && + (ubq->flags & UBLK_F_USER_RECOVERY_REISSUE)) + return true; + return false; +} + static void ublk_free_disk(struct gendisk *disk) { struct ublk_device *ub = disk->private_data; diff --git a/include/uapi/linux/ublk_cmd.h b/include/uapi/linux/ublk_cmd.h index 677edaab2b66..7f7e6f44cec5 100644 --- a/include/uapi/linux/ublk_cmd.h +++ b/include/uapi/linux/ublk_cmd.h @@ -17,6 +17,8 @@ #define UBLK_CMD_STOP_DEV 0x07 #define UBLK_CMD_SET_PARAMS 0x08 #define UBLK_CMD_GET_PARAMS 0x09 +#define UBLK_CMD_START_USER_RECOVERY 0x10 +#define UBLK_CMD_END_USER_RECOVERY 0x11 /* * IO commands, issued by ublk server, and handled by ublk driver. @@ -74,9 +76,14 @@ */ #define UBLK_F_NEED_GET_DATA (1UL << 2) +#define UBLK_F_USER_RECOVERY (1UL << 3) + +#define UBLK_F_USER_RECOVERY_REISSUE (1UL << 4) + /* device state */ #define UBLK_S_DEV_DEAD 0 #define UBLK_S_DEV_LIVE 1 +#define UBLK_S_DEV_RECOVERING 2 /* shipped via sqe->cmd of io_uring command */ struct ublksrv_ctrl_cmd {