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 X-Spam-Level: X-Spam-Status: No, score=-13.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EC0E8C4363D for ; Mon, 5 Oct 2020 09:43:09 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 869152080C for ; Mon, 5 Oct 2020 09:43:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="frdXMB5w" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 869152080C Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:MIME-Version:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:References:In-Reply-To:Message-Id:Date:Subject:To: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=uyUOt2/ZjtHIPI0GEU4DgU2XQQexxLeoVpsaA9B7RSs=; b=frdXMB5wn6Y2yPrT9s0svWV/IY pbgy7Xx/kAHbnouQHd/EOYNJ7IQNVWrAVQZ3PuWouBWqKxBXrrQN1Kwg1M1UiLXlNIH73ctsUzTEZ 6lcIil7C9XYiVcqWcgSxirptY2+ahY1wVDmNVIZY/vj0AkTdMvlrRc2X7O26S7MHUCk/hrAc5RIRd 8bGTAmrYVd+zP9IqCdbfXVr2CzANLa4jEPCgD5ZnRxjyI29gpmsmw4qgoqTCUx2DRJJ9EHC01FeRX Iyk+IZYlbDQqJDrbss0NzKRTNNDE/UQP91nJIyFugaT2AJjA4rXOKNJ00sPF+2xUxenRaOhLKUFPM ZF2KX7MA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1kPN1O-0004DF-Mx; Mon, 05 Oct 2020 09:43:06 +0000 Received: from mx2.suse.de ([195.135.220.15]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1kPN1I-0004B9-MC for linux-nvme@lists.infradead.org; Mon, 05 Oct 2020 09:43:03 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 4E423AB54; Mon, 5 Oct 2020 09:42:58 +0000 (UTC) From: Hannes Reinecke To: Christoph Hellwig Subject: [PATCH 1/3] nvme-mpath: delete disk after last connection Date: Mon, 5 Oct 2020 11:42:54 +0200 Message-Id: <20201005094256.49358-2-hare@suse.de> X-Mailer: git-send-email 2.16.4 In-Reply-To: <20201005094256.49358-1-hare@suse.de> References: <20201005094256.49358-1-hare@suse.de> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201005_054300_976573_C9DC4269 X-CRM114-Status: GOOD ( 20.61 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Keith Busch , linux-nvme@lists.infradead.org, Sagi Grimberg , Keith Busch MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org From: Keith Busch The multipath code currently deletes the disk only after all references to it are dropped rather than when the last path to that disk is lost. This has been reported to cause problems with some usage, like MD RAID. Delete the disk when the last path is gone. This is the same behavior we currently have with non-multipathed nvme devices. The following is just a simple example that demonstrates what is currently observed using a simple nvme loop back (loop setup file not shown): # nvmetcli restore loop.json [ 31.156452] nvmet: adding nsid 1 to subsystem testnqn1 [ 31.159140] nvmet: adding nsid 1 to subsystem testnqn2 # nvme connect -t loop -n testnqn1 -q hostnqn [ 36.866302] nvmet: creating controller 1 for subsystem testnqn1 for NQN hostnqn. [ 36.872926] nvme nvme3: new ctrl: "testnqn1" # nvme connect -t loop -n testnqn1 -q hostnqn [ 38.227186] nvmet: creating controller 2 for subsystem testnqn1 for NQN hostnqn. [ 38.234450] nvme nvme4: new ctrl: "testnqn1" # nvme connect -t loop -n testnqn2 -q hostnqn [ 43.902761] nvmet: creating controller 3 for subsystem testnqn2 for NQN hostnqn. [ 43.907401] nvme nvme5: new ctrl: "testnqn2" # nvme connect -t loop -n testnqn2 -q hostnqn [ 44.627689] nvmet: creating controller 4 for subsystem testnqn2 for NQN hostnqn. [ 44.641773] nvme nvme6: new ctrl: "testnqn2" # mdadm --create /dev/md0 --level=mirror --raid-devices=2 /dev/nvme3n1 /dev/nvme5n1 [ 53.497038] md/raid1:md0: active with 2 out of 2 mirrors [ 53.501717] md0: detected capacity change from 0 to 66060288 # cat /proc/mdstat Personalities : [raid1] md0 : active raid1 nvme5n1[1] nvme3n1[0] 64512 blocks super 1.2 [2/2] [UU] Now delete all paths to one of the namespaces: # echo 1 > /sys/class/nvme/nvme3/delete_controller # echo 1 > /sys/class/nvme/nvme4/delete_controller We have no path, but mdstat says: # cat /proc/mdstat Personalities : [raid1] md0 : active (auto-read-only) raid1 nvme5n1[1] 64512 blocks super 1.2 [2/1] [_U] And this is reported to cause a problem. With the proposed patch, the following messages appear: [ 227.516807] md/raid1:md0: Disk failure on nvme3n1, disabling device. [ 227.516807] md/raid1:md0: Operation continuing on 1 devices. And mdstat shows only the viable members: # cat /proc/mdstat Personalities : [raid1] md0 : active (auto-read-only) raid1 nvme5n1[1] 64512 blocks super 1.2 [2/1] [_U] Reported-by: Hannes Reinecke Signed-off-by: Keith Busch --- drivers/nvme/host/core.c | 3 ++- drivers/nvme/host/multipath.c | 1 - drivers/nvme/host/nvme.h | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index 385b10317873..af950d58c562 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -474,7 +474,8 @@ static void nvme_free_ns_head(struct kref *ref) struct nvme_ns_head *head = container_of(ref, struct nvme_ns_head, ref); - nvme_mpath_remove_disk(head); + if (head->disk) + put_disk(head->disk); ida_simple_remove(&head->subsys->ns_ida, head->instance); cleanup_srcu_struct(&head->srcu); nvme_put_subsystem(head->subsys); diff --git a/drivers/nvme/host/multipath.c b/drivers/nvme/host/multipath.c index 74896be40c17..55045291b4de 100644 --- a/drivers/nvme/host/multipath.c +++ b/drivers/nvme/host/multipath.c @@ -697,7 +697,6 @@ void nvme_mpath_remove_disk(struct nvme_ns_head *head) */ head->disk->queue = NULL; } - put_disk(head->disk); } int nvme_mpath_init(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id) diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h index 566776100126..b6180bb3361d 100644 --- a/drivers/nvme/host/nvme.h +++ b/drivers/nvme/host/nvme.h @@ -670,7 +670,7 @@ static inline void nvme_mpath_check_last_path(struct nvme_ns *ns) struct nvme_ns_head *head = ns->head; if (head->disk && list_empty(&head->list)) - kblockd_schedule_work(&head->requeue_work); + nvme_mpath_remove_disk(head); } static inline void nvme_trace_bio_complete(struct request *req, -- 2.16.4 _______________________________________________ Linux-nvme mailing list Linux-nvme@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-nvme