From 47525e59e40ffb8cbc944c0055e9c4902cd3ee99 Mon Sep 17 00:00:00 2001 From: Jonathan Brassow Date: Tue, 22 May 2012 13:55:29 +1000 Subject: [PATCH] DM RAID: Set recovery flags on resume Properly initialize MD recovery flags when resuming device-mapper devices. When a device-mapper device is suspended, all I/O must stop. This is done by calling 'md_stop_writes' and 'mddev_suspend'. These calls in-turn manipulate the recovery flags - including setting 'MD_RECOVERY_FROZEN'. The DM device may have been suspended while recovery was not yet complete, so the process needs to pick-up where it left off. Since 'mddev_resume' does not unset 'MD_RECOVERY_FROZEN' and set 'MD_RECOVERY_NEEDED', we must do it ourselves. 'MD_RECOVERY_NEEDED' can safely be set in 'mddev_resume', but 'MD_RECOVERY_FROZEN' must be set outside of 'mddev_resume' due to how MD handles RAID reshaping. (e.g. It is possible for a user to delay reshaping a RAID5->RAID6 by purposefully setting 'MD_RECOVERY_FROZEN'. Clearing it in 'mddev_resume' would override the desired behavior.) Because 'mddev_resume' already unconditionally calls 'md_wakeup_thread(mddev->thread)' there is no need to make this call from 'raid_resume' since it calls 'mddev_resume'. Also clean up where level_store calls mddev_resume() - it current duplicates some of the funcitons of that call. - NB Signed-off-by: Jonathan Brassow Signed-off-by: NeilBrown --- drivers/md/dm-raid.c | 4 ++-- drivers/md/md.c | 5 ++--- 2 files changed, 4 insertions(+), 5 deletions(-) diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index 73a068da10d9..ea2d90c78f78 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -1252,9 +1252,9 @@ static void raid_resume(struct dm_target *ti) if (!rs->bitmap_loaded) { bitmap_load(&rs->md); rs->bitmap_loaded = 1; - } else - md_wakeup_thread(rs->md.thread); + } + clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); mddev_resume(&rs->md); } diff --git a/drivers/md/md.c b/drivers/md/md.c index 86adf4ac46cf..4c9836885d3e 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -402,6 +402,7 @@ void mddev_resume(struct mddev *mddev) wake_up(&mddev->sb_wait); mddev->pers->quiesce(mddev, 0); + set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); md_wakeup_thread(mddev->thread); md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */ } @@ -3673,10 +3674,8 @@ level_store(struct mddev *mddev, const char *buf, size_t len) del_timer_sync(&mddev->safemode_timer); } pers->run(mddev); - mddev_resume(mddev); set_bit(MD_CHANGE_DEVS, &mddev->flags); - set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); - md_wakeup_thread(mddev->thread); + mddev_resume(mddev); sysfs_notify(&mddev->kobj, NULL, "level"); md_new_event(mddev); return rv;