From 31a59e3425d32743738e043c1df1668e0f22bbab Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 30 Apr 2008 00:52:30 -0700 Subject: [PATCH] md: fix 'safemode' handling for external metadata. 'safemode' relates to marking an array as 'clean' if there has been no write traffic for a while (a couple of seconds), to reduce the chance of the array being found dirty on reboot. ->safemode is set to '1' when there have been no write for a while, and it gets set to '0' when the superblock is updates with the 'clean' flag set. This requires a few fixes for 'external' metadata: - When an array is set to 'clean' via sysfs, 'safemode' must be cleared. - when we write to an array that has 'safemode' set (there must have been some delay in updating the metadata), we need to clear safemode. - Don't try to update external metadata in md_check_recovery for safemode transitions - it won't work. Also, don't try to support "immediate safe mode" (safemode==2) for external metadata, it cannot really work (the safemode timeout can be set very low if this is really needed). Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/md/md.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/drivers/md/md.c b/drivers/md/md.c index 7a44c81ae3cd..ff9fef389608 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -2615,6 +2615,8 @@ array_state_store(mddev_t *mddev, const char *buf, size_t len) if (atomic_read(&mddev->writes_pending) == 0) { if (mddev->in_sync == 0) { mddev->in_sync = 1; + if (mddev->safemode == 1) + mddev->safemode = 0; if (mddev->persistent) set_bit(MD_CHANGE_CLEAN, &mddev->flags); @@ -5392,6 +5394,8 @@ void md_write_start(mddev_t *mddev, struct bio *bi) md_wakeup_thread(mddev->sync_thread); } atomic_inc(&mddev->writes_pending); + if (mddev->safemode == 1) + mddev->safemode = 0; if (mddev->in_sync) { spin_lock_irq(&mddev->write_lock); if (mddev->in_sync) { @@ -5816,7 +5820,7 @@ void md_check_recovery(mddev_t *mddev) return; if (signal_pending(current)) { - if (mddev->pers->sync_request) { + if (mddev->pers->sync_request && !mddev->external) { printk(KERN_INFO "md: %s in immediate safe mode\n", mdname(mddev)); mddev->safemode = 2; @@ -5828,7 +5832,7 @@ void md_check_recovery(mddev_t *mddev) (mddev->flags && !mddev->external) || test_bit(MD_RECOVERY_NEEDED, &mddev->recovery) || test_bit(MD_RECOVERY_DONE, &mddev->recovery) || - (mddev->safemode == 1) || + (mddev->external == 0 && mddev->safemode == 1) || (mddev->safemode == 2 && ! atomic_read(&mddev->writes_pending) && !mddev->in_sync && mddev->recovery_cp == MaxSector) )) @@ -5837,16 +5841,20 @@ void md_check_recovery(mddev_t *mddev) if (mddev_trylock(mddev)) { int spares = 0; - spin_lock_irq(&mddev->write_lock); - if (mddev->safemode && !atomic_read(&mddev->writes_pending) && - !mddev->in_sync && mddev->recovery_cp == MaxSector) { - mddev->in_sync = 1; - if (mddev->persistent) - set_bit(MD_CHANGE_CLEAN, &mddev->flags); + if (!mddev->external) { + spin_lock_irq(&mddev->write_lock); + if (mddev->safemode && + !atomic_read(&mddev->writes_pending) && + !mddev->in_sync && + mddev->recovery_cp == MaxSector) { + mddev->in_sync = 1; + if (mddev->persistent) + set_bit(MD_CHANGE_CLEAN, &mddev->flags); + } + if (mddev->safemode == 1) + mddev->safemode = 0; + spin_unlock_irq(&mddev->write_lock); } - if (mddev->safemode == 1) - mddev->safemode = 0; - spin_unlock_irq(&mddev->write_lock); if (mddev->flags) md_update_sb(mddev, 0); -- 2.20.1