From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6AEE61DF246; Thu, 17 Apr 2025 18:37:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744915073; cv=none; b=SODm0nC7TP2XZFrEcwdxNS5lEe5eO58XwjE8gWQj3XW2JR6ZecvAA+JJZLaYZT98Ir2Dt2bHEFrCub9YpmwEiozpfrueHmMs83OJ6ruD2UWs4/e/xRd7p+haL+nadGp4LytSth90ZfrPeSkTFOm4YvdTRl1ME4UsE94jrPmXzFI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744915073; c=relaxed/simple; bh=9qDmeIVQf7rOqxZp5e+oqHlEpSJIUsy8XJEy0zhVon4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ZQrnbTiaa3C8Gdlu7yoYDopMJdqF6PGWCkZpTQn8R8+I7nxKQXJVHiKWLp9zJfiUUSFVesJ47VGEZ7JNI/iNQTFkFv6uJ+D6fGJbO9T8k2FZv/FTd8DggQ/Fv5UaBc1WvbXzAvSmxvhZ9OB1k6H/YKUk/5il2CaqOZE5Pk5Q/7Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=cPNIcvR7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="cPNIcvR7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D9A93C4CEE4; Thu, 17 Apr 2025 18:37:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1744915073; bh=9qDmeIVQf7rOqxZp5e+oqHlEpSJIUsy8XJEy0zhVon4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cPNIcvR7WINNlKLSj9IzSdDjegZORqP2gqw3EPQCe11aYy1IAE6e2T3NXlqABvxPC 7+IcZLOKWNpDJneYhpCyKv6XsuHTaqtg/jEWtD4IzPegNSd9TMnV5tyNO/goFf4AD/ U2jAm9gqehWKBw7x7rrlC5ziWQoeDOyiembZZueE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Uday Shankar , Ming Lei , Jens Axboe , Sasha Levin Subject: [PATCH 6.12 010/393] ublk: refactor recovery configuration flag helpers Date: Thu, 17 Apr 2025 19:46:59 +0200 Message-ID: <20250417175107.992794917@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250417175107.546547190@linuxfoundation.org> References: <20250417175107.546547190@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Uday Shankar [ Upstream commit 3b939b8f715e014adcc48f7827fe9417252f0833 ] ublk currently supports the following behaviors on ublk server exit: A: outstanding I/Os get errors, subsequently issued I/Os get errors B: outstanding I/Os get errors, subsequently issued I/Os queue C: outstanding I/Os get reissued, subsequently issued I/Os queue and the following behaviors for recovery of preexisting block devices by a future incarnation of the ublk server: 1: ublk devices stopped on ublk server exit (no recovery possible) 2: ublk devices are recoverable using start/end_recovery commands The userspace interface allows selection of combinations of these behaviors using flags specified at device creation time, namely: default behavior: A + 1 UBLK_F_USER_RECOVERY: B + 2 UBLK_F_USER_RECOVERY|UBLK_F_USER_RECOVERY_REISSUE: C + 2 We can't easily change the userspace interface to allow independent selection of one of {A, B, C} and one of {1, 2}, but we can refactor the internal helpers which test for the flags. Replace the existing helpers with the following set: ublk_nosrv_should_reissue_outstanding: tests for behavior C ublk_nosrv_[dev_]should_queue_io: tests for behavior B ublk_nosrv_should_stop_dev: tests for behavior 1 Signed-off-by: Uday Shankar Reviewed-by: Ming Lei Link: https://lore.kernel.org/r/20241007182419.3263186-3-ushankar@purestorage.com Signed-off-by: Jens Axboe Stable-dep-of: 6ee6bd5d4fce ("ublk: fix handling recovery & reissue in ublk_abort_queue()") Signed-off-by: Sasha Levin --- drivers/block/ublk_drv.c | 62 +++++++++++++++++++++++++++------------- 1 file changed, 42 insertions(+), 20 deletions(-) diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 79b7bd8bfd458..dd328d40c7de5 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -681,22 +681,44 @@ static int ublk_max_cmd_buf_size(void) return __ublk_queue_cmd_buf_size(UBLK_MAX_QUEUE_DEPTH); } -static inline bool ublk_queue_can_use_recovery_reissue( - struct ublk_queue *ubq) +/* + * Should I/O outstanding to the ublk server when it exits be reissued? + * If not, outstanding I/O will get errors. + */ +static inline bool ublk_nosrv_should_reissue_outstanding(struct ublk_device *ub) { - return (ubq->flags & UBLK_F_USER_RECOVERY) && - (ubq->flags & UBLK_F_USER_RECOVERY_REISSUE); + return (ub->dev_info.flags & UBLK_F_USER_RECOVERY) && + (ub->dev_info.flags & UBLK_F_USER_RECOVERY_REISSUE); } -static inline bool ublk_queue_can_use_recovery( - struct ublk_queue *ubq) +/* + * Should I/O issued while there is no ublk server queue? If not, I/O + * issued while there is no ublk server will get errors. + */ +static inline bool ublk_nosrv_dev_should_queue_io(struct ublk_device *ub) +{ + return ub->dev_info.flags & UBLK_F_USER_RECOVERY; +} + +/* + * Same as ublk_nosrv_dev_should_queue_io, but uses a queue-local copy + * of the device flags for smaller cache footprint - better for fast + * paths. + */ +static inline bool ublk_nosrv_should_queue_io(struct ublk_queue *ubq) { return ubq->flags & UBLK_F_USER_RECOVERY; } -static inline bool ublk_can_use_recovery(struct ublk_device *ub) +/* + * Should ublk devices be stopped (i.e. no recovery possible) when the + * ublk server exits? If not, devices can be used again by a future + * incarnation of a ublk server via the start_recovery/end_recovery + * commands. + */ +static inline bool ublk_nosrv_should_stop_dev(struct ublk_device *ub) { - return ub->dev_info.flags & UBLK_F_USER_RECOVERY; + return !(ub->dev_info.flags & UBLK_F_USER_RECOVERY); } static void ublk_free_disk(struct gendisk *disk) @@ -1072,7 +1094,7 @@ static void __ublk_fail_req(struct ublk_queue *ubq, struct ublk_io *io, { WARN_ON_ONCE(io->flags & UBLK_IO_FLAG_ACTIVE); - if (ublk_queue_can_use_recovery_reissue(ubq)) + if (ublk_nosrv_should_reissue_outstanding(ubq->dev)) blk_mq_requeue_request(req, false); else ublk_put_req_ref(ubq, req); @@ -1100,7 +1122,7 @@ static inline void __ublk_abort_rq(struct ublk_queue *ubq, struct request *rq) { /* We cannot process this rq so just requeue it. */ - if (ublk_queue_can_use_recovery(ubq)) + if (ublk_nosrv_dev_should_queue_io(ubq->dev)) blk_mq_requeue_request(rq, false); else blk_mq_end_request(rq, BLK_STS_IOERR); @@ -1245,10 +1267,10 @@ static enum blk_eh_timer_return ublk_timeout(struct request *rq) struct ublk_device *ub = ubq->dev; if (ublk_abort_requests(ub, ubq)) { - if (ublk_can_use_recovery(ub)) - schedule_work(&ub->quiesce_work); - else + if (ublk_nosrv_should_stop_dev(ub)) schedule_work(&ub->stop_work); + else + schedule_work(&ub->quiesce_work); } return BLK_EH_DONE; } @@ -1277,7 +1299,7 @@ static blk_status_t ublk_queue_rq(struct blk_mq_hw_ctx *hctx, * Note: force_abort is guaranteed to be seen because it is set * before request queue is unqiuesced. */ - if (ublk_queue_can_use_recovery(ubq) && unlikely(ubq->force_abort)) + if (ublk_nosrv_should_queue_io(ubq) && unlikely(ubq->force_abort)) return BLK_STS_IOERR; if (unlikely(ubq->canceling)) { @@ -1517,10 +1539,10 @@ static void ublk_uring_cmd_cancel_fn(struct io_uring_cmd *cmd, ublk_cancel_cmd(ubq, io, issue_flags); if (need_schedule) { - if (ublk_can_use_recovery(ub)) - schedule_work(&ub->quiesce_work); - else + if (ublk_nosrv_should_stop_dev(ub)) schedule_work(&ub->stop_work); + else + schedule_work(&ub->quiesce_work); } } @@ -1640,7 +1662,7 @@ static void ublk_stop_dev(struct ublk_device *ub) mutex_lock(&ub->mutex); if (ub->dev_info.state == UBLK_S_DEV_DEAD) goto unlock; - if (ublk_can_use_recovery(ub)) { + if (ublk_nosrv_dev_should_queue_io(ub)) { if (ub->dev_info.state == UBLK_S_DEV_LIVE) __ublk_quiesce_dev(ub); ublk_unquiesce_dev(ub); @@ -2738,7 +2760,7 @@ static int ublk_ctrl_start_recovery(struct ublk_device *ub, int i; mutex_lock(&ub->mutex); - if (!ublk_can_use_recovery(ub)) + if (ublk_nosrv_should_stop_dev(ub)) goto out_unlock; if (!ub->nr_queues_ready) goto out_unlock; @@ -2791,7 +2813,7 @@ static int ublk_ctrl_end_recovery(struct ublk_device *ub, __func__, ub->dev_info.nr_hw_queues, header->dev_id); mutex_lock(&ub->mutex); - if (!ublk_can_use_recovery(ub)) + if (ublk_nosrv_should_stop_dev(ub)) goto out_unlock; if (ub->dev_info.state != UBLK_S_DEV_QUIESCED) { -- 2.39.5