From mboxrd@z Thu Jan 1 00:00:00 1970 From: Song Liu Subject: [PATCH v2] md/r5cache: journal remove support Date: Wed, 15 Mar 2017 14:15:08 -0700 Message-ID: <20170315211508.4000145-1-songliubraving@fb.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org Cc: shli@fb.com, neilb@suse.com, kernel-team@fb.com, dan.j.williams@intel.com, hch@infradead.org, jes.sorensen@gmail.com, Song Liu List-Id: linux-raid.ids When journal device of an array fails, the array is forced into read-only mode. To make the array normal without adding another journal device, we need to remove journal _feature_ from the array. This patch allows remove journal _feature_ from an array, For journal remove to work, existing journal should be either missing or faulty. Two flags are added to GET_ARRAY_INFO for mdadm. 1. MD_SB_HAS_JOURNAL: meaning the array have journal feature; 2. MD_SB_JOURNAL_REMOVABLE: meaning the journal is faulty or missing When both flags are set, mdadm can clear MD_SB_HAS_JOURNAL to remove journal _feature_. Signed-off-by: Song Liu --- drivers/md/md.c | 44 ++++++++++++++++++++++++++++++++++++++++-- include/uapi/linux/raid/md_p.h | 11 ++++++++--- 2 files changed, 50 insertions(+), 5 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index ac3bd15..14bf4c3 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -5981,6 +5981,25 @@ static void autorun_devices(int part) } #endif /* !MODULE */ +/* + * the journal _feature_ is removable when: + * the array has journal support && + * (journal is missing || journal is faulty) + */ +static bool journal_removable(struct mddev *mddev) +{ + struct md_rdev *rdev; + + if (!test_bit(MD_HAS_JOURNAL, &mddev->flags)) + return false; + + rdev_for_each_rcu(rdev, mddev) + if (test_bit(Journal, &rdev->flags) && + !test_bit(Faulty, &rdev->flags)) + return false; + return true; +} + static int get_version(void __user *arg) { mdu_version_t ver; @@ -6041,6 +6060,10 @@ static int get_array_info(struct mddev *mddev, void __user *arg) info.state |= (1<flags)) + info.state |= (1<bitmap && mddev->bitmap_info.offset) state |= (1 << MD_SB_BITMAP_PRESENT); + if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) + state |= (1 << MD_SB_HAS_JOURNAL); + if (journal_removable(mddev)) + state |= (1 << MD_SB_JOURNAL_REMOVABLE); if (mddev->major_version != info->major_version || mddev->minor_version != info->minor_version || @@ -6730,8 +6757,11 @@ static int update_array_info(struct mddev *mddev, mdu_array_info_t *info) /* mddev->layout != info->layout || */ mddev->persistent != !info->not_persistent || mddev->chunk_sectors != info->chunk_size >> 9 || - /* ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT to change */ - ((state^info->state) & 0xfffffe00) + /* + * ignore bottom 8 bits of state, and allow SB_BITMAP_PRESENT + * and SB_HAS_JOURNAL to change + */ + ((state^info->state) & 0xfffffc00) ) return -EINVAL; /* Check there is only one change */ @@ -6743,6 +6773,8 @@ static int update_array_info(struct mddev *mddev, mdu_array_info_t *info) cnt++; if ((state ^ info->state) & (1<state) & (1< 1) @@ -6831,6 +6863,14 @@ static int update_array_info(struct mddev *mddev, mdu_array_info_t *info) mddev->bitmap_info.offset = 0; } } + if ((state ^ info->state) & (1<flags); + } + md_update_sb(mddev, 1); return rv; err: diff --git a/include/uapi/linux/raid/md_p.h b/include/uapi/linux/raid/md_p.h index d9a1ead..b1f2b63 100644 --- a/include/uapi/linux/raid/md_p.h +++ b/include/uapi/linux/raid/md_p.h @@ -1,15 +1,15 @@ /* md_p.h : physical layout of Linux RAID devices Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman - + This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. - + You should have received a copy of the GNU General Public License (for example /usr/src/linux/COPYING); if not, write to the Free - Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #ifndef _MD_P_H @@ -119,6 +119,11 @@ typedef struct mdp_device_descriptor_s { #define MD_SB_CLUSTERED 5 /* MD is clustered */ #define MD_SB_BITMAP_PRESENT 8 /* bitmap may be present nearby */ +#define MD_SB_HAS_JOURNAL 9 +#define MD_SB_JOURNAL_REMOVABLE 10 /* journal _feature_ can be removed, + * which means the journal is either + * missing or Faulty + */ /* * Notes: -- 2.9.3