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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9D858C0015E for ; Fri, 21 Jul 2023 19:22:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232174AbjGUTWq (ORCPT ); Fri, 21 Jul 2023 15:22:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44274 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232114AbjGUTWp (ORCPT ); Fri, 21 Jul 2023 15:22:45 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C3D14189 for ; Fri, 21 Jul 2023 12:22:44 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 4B4C361D2F for ; Fri, 21 Jul 2023 19:22:44 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 59DABC433C7; Fri, 21 Jul 2023 19:22:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1689967363; bh=Unv47NniIiIeazTAvZLeKaDyGWL5SwOunDtkZdWrpvI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UZhWH5h6cwNiVngRO9TG+ftB54muQJxQ9M4Itf0bwvJ4R/7Fue+aT7lAmqJ2cdWNf 7VDu5l3vc9p7Tbpr/FYjXPsOXJ3yCzGc/N90d2/eJMlpOAlcm4GkrSzGhyyIKiar+j /YtI8eJoBiuSGTy+ARCJ51Y1k+GzvPVSAYz6Duqs= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Peter Korsgaard , Mike Snitzer , Mark-PK Tsai Subject: [PATCH 6.1 136/223] dm init: add dm-mod.waitfor to wait for asynchronously probed block devices Date: Fri, 21 Jul 2023 18:06:29 +0200 Message-ID: <20230721160526.674339254@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230721160520.865493356@linuxfoundation.org> References: <20230721160520.865493356@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Peter Korsgaard commit 035641b01e72af4f6c6cf22a4bdb5d7dfc4e8e8e upstream. Just calling wait_for_device_probe() is not enough to ensure that asynchronously probed block devices are available (E.G. mmc, usb), so add a "dm-mod.waitfor=[,..,]" parameter to get dm-init to explicitly wait for specific block devices before initializing the tables with logic similar to the rootwait logic that was introduced with commit cc1ed7542c8c ("init: wait for asynchronously scanned block devices"). E.G. with dm-verity on mmc using: dm-mod.waitfor="PARTLABEL=hash-a,PARTLABEL=root-a" [ 0.671671] device-mapper: init: waiting for all devices to be available before creating mapped devices [ 0.671679] device-mapper: init: waiting for device PARTLABEL=hash-a ... [ 0.710695] mmc0: new HS200 MMC card at address 0001 [ 0.711158] mmcblk0: mmc0:0001 004GA0 3.69 GiB [ 0.715954] mmcblk0boot0: mmc0:0001 004GA0 partition 1 2.00 MiB [ 0.722085] mmcblk0boot1: mmc0:0001 004GA0 partition 2 2.00 MiB [ 0.728093] mmcblk0rpmb: mmc0:0001 004GA0 partition 3 512 KiB, chardev (249:0) [ 0.738274] mmcblk0: p1 p2 p3 p4 p5 p6 p7 [ 0.751282] device-mapper: init: waiting for device PARTLABEL=root-a ... [ 0.751306] device-mapper: init: all devices available [ 0.751683] device-mapper: verity: sha256 using implementation "sha256-generic" [ 0.759344] device-mapper: ioctl: dm-0 (vroot) is ready [ 0.766540] VFS: Mounted root (squashfs filesystem) readonly on device 254:0. Signed-off-by: Peter Korsgaard Signed-off-by: Mike Snitzer Cc: Mark-PK Tsai Signed-off-by: Greg Kroah-Hartman --- Documentation/admin-guide/device-mapper/dm-init.rst | 8 +++++++ drivers/md/dm-init.c | 22 +++++++++++++++++++- 2 files changed, 29 insertions(+), 1 deletion(-) --- a/Documentation/admin-guide/device-mapper/dm-init.rst +++ b/Documentation/admin-guide/device-mapper/dm-init.rst @@ -123,3 +123,11 @@ Other examples (per target): 0 1638400 verity 1 8:1 8:2 4096 4096 204800 1 sha256 fb1a5a0f00deb908d8b53cb270858975e76cf64105d412ce764225d53b8f3cfd 51934789604d1b92399c52e7cb149d1b3a1b74bbbcb103b2a0aaacbed5c08584 + +For setups using device-mapper on top of asynchronously probed block +devices (MMC, USB, ..), it may be necessary to tell dm-init to +explicitly wait for them to become available before setting up the +device-mapper tables. This can be done with the "dm-mod.waitfor=" +module parameter, which takes a list of devices to wait for:: + + dm-mod.waitfor=[,..,] --- a/drivers/md/dm-init.c +++ b/drivers/md/dm-init.c @@ -8,6 +8,7 @@ */ #include +#include #include #include #include @@ -18,12 +19,17 @@ #define DM_MAX_DEVICES 256 #define DM_MAX_TARGETS 256 #define DM_MAX_STR_SIZE 4096 +#define DM_MAX_WAITFOR 256 static char *create; +static char *waitfor[DM_MAX_WAITFOR]; + /* * Format: dm-mod.create=,,,,[,
+][;,,,,
[,
+]+] * Table format: + * Block devices to wait for to become available before setting up tables: + * dm-mod.waitfor=[,..,] * * See Documentation/admin-guide/device-mapper/dm-init.rst for dm-mod.create="..." format * details. @@ -266,7 +272,7 @@ static int __init dm_init_init(void) struct dm_device *dev; LIST_HEAD(devices); char *str; - int r; + int i, r; if (!create) return 0; @@ -286,6 +292,17 @@ static int __init dm_init_init(void) DMINFO("waiting for all devices to be available before creating mapped devices"); wait_for_device_probe(); + for (i = 0; i < ARRAY_SIZE(waitfor); i++) { + if (waitfor[i]) { + DMINFO("waiting for device %s ...", waitfor[i]); + while (!dm_get_dev_t(waitfor[i])) + msleep(5); + } + } + + if (waitfor[0]) + DMINFO("all devices available"); + list_for_each_entry(dev, &devices, list) { if (dm_early_create(&dev->dmi, dev->table, dev->target_args_array)) @@ -301,3 +318,6 @@ late_initcall(dm_init_init); module_param(create, charp, 0); MODULE_PARM_DESC(create, "Create a mapped device in early boot"); + +module_param_array(waitfor, charp, NULL, 0); +MODULE_PARM_DESC(waitfor, "Devices to wait for before setting up tables");