From patchwork Tue Sep 13 04:17:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ziyang Zhang X-Patchwork-Id: 12974327 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 AE81FC6FA82 for ; Tue, 13 Sep 2022 04:19:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230049AbiIMETB (ORCPT ); Tue, 13 Sep 2022 00:19:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37510 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230050AbiIMESz (ORCPT ); Tue, 13 Sep 2022 00:18:55 -0400 Received: from out30-132.freemail.mail.aliyun.com (out30-132.freemail.mail.aliyun.com [115.124.30.132]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A691F4D150; Mon, 12 Sep 2022 21:18:52 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R921e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046051;MF=ziyangzhang@linux.alibaba.com;NM=1;PH=DS;RN=7;SR=0;TI=SMTPD_---0VPccyFG_1663042729; Received: from localhost.localdomain(mailfrom:ZiyangZhang@linux.alibaba.com fp:SMTPD_---0VPccyFG_1663042729) by smtp.aliyun-inc.com; Tue, 13 Sep 2022 12:18:50 +0800 From: ZiyangZhang To: ming.lei@redhat.com Cc: axboe@kernel.dk, xiaoguang.wang@linux.alibaba.com, linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, joseph.qi@linux.alibaba.com, ZiyangZhang Subject: [PATCH V3 3/7] ublk_drv: define macros for recovery feature and check them Date: Tue, 13 Sep 2022 12:17:03 +0800 Message-Id: <20220913041707.197334-4-ZiyangZhang@linux.alibaba.com> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20220913041707.197334-1-ZiyangZhang@linux.alibaba.com> References: <20220913041707.197334-1-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_QUIESCED which implies that ublk_device is quiesced and is ready for recovery. This state can be observed by userspace. 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. (2) With a dying ubq_daemon, ublk_drv ends(aborts) rqs issued to userspace(ublksrv) before crash. (3) With a dying ubq_daemon, in task work and ublk_queue_rq(), ublk_drv requeues rqs. UBLK_F_USER_RECOVERY_REISSUE implies that: (1) everything UBLK_F_USER_RECOVERY implies except (2) With a dying ubq_daemon, ublk_drv requeues rqs issued to userspace(ublksrv) before crash. UBLK_F_USER_RECOVERY_REISSUE is designed for backends which: (1) tolerates double-writes because ublk_drv may issue the same rq twice. (2) does not let frontend users get I/O error. such as read-only FS and VM backend. Signed-off-by: ZiyangZhang --- drivers/block/ublk_drv.c | 45 ++++++++++++++++++++++++++++++++++- include/uapi/linux/ublk_cmd.h | 7 ++++++ 2 files changed, 51 insertions(+), 1 deletion(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 0c6db0978ed0..23337bd7c105 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 +325,47 @@ static inline int ublk_queue_cmd_buf_size(struct ublk_device *ub, int q_id) PAGE_SIZE); } +static inline bool ublk_queue_can_use_recovery( + struct ublk_queue *ubq) +{ + if (ubq->flags & UBLK_F_USER_RECOVERY) + return true; + return false; +} + +static inline void ublk_disable_recovery(struct ublk_device *ub) +{ + int i; + + for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { + struct ublk_queue *ubq = ublk_get_queue(ub, i); + + ubq->flags &= ~UBLK_F_USER_RECOVERY; + } +} + +static inline bool ublk_can_use_recovery(struct ublk_device *ub) +{ + int i; + + for (i = 0; i < ub->dev_info.nr_hw_queues; i++) { + struct ublk_queue *ubq = ublk_get_queue(ub, i); + + if (!ublk_queue_can_use_recovery(ubq)) + return false; + } + return true; +} + +static inline bool ublk_queue_can_use_recovery_reissue( + struct ublk_queue *ubq) +{ + if (ublk_queue_can_use_recovery(ubq) && + (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..87204c39f1ee 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_QUIESCED 2 /* shipped via sqe->cmd of io_uring command */ struct ublksrv_ctrl_cmd {