From e691063a61f7f72a7d2882eb744b07a520cde23b Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Wed, 6 Feb 2008 01:39:51 -0800 Subject: md: support 'external' metadata for md arrays - Add a state flag 'external' to indicate that the metadata is managed externally (by user-space) so important changes need to be left of user-space to handle. Alternates are non-persistant ('none') where there is no stable metadata - after the array is stopped there is no record of it's status - and internal which can be version 0.90 or version 1.x These are selected by writing to the 'metadata' attribute. - move the updating of superblocks (sync_sbs) to after we have checked if there are any superblocks or not. - New array state 'write_pending'. This means that the metadata records the array as 'clean', but a write has been requested, so the metadata has to be updated to record a 'dirty' array before the write can continue. This change is reported to md by writing 'active' to the array_state attribute. - tidy up marking of sb_dirty: - don't set sb_dirty when resync finishes as md_check_recovery calls md_update_sb when the sync thread finishes anyway. - Don't set sb_dirty in multipath_run as the array might not be dirty. - don't mark superblock dirty when switching to 'clean' if there is no internal superblock (if external, userspace can choose to update the superblock whenever it chooses to). Signed-off-by: Neil Brown Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/raid/md_k.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/linux') diff --git a/include/linux/raid/md_k.h b/include/linux/raid/md_k.h index dcb729244f4..b579cc62830 100644 --- a/include/linux/raid/md_k.h +++ b/include/linux/raid/md_k.h @@ -130,6 +130,9 @@ struct mddev_s minor_version, patch_version; int persistent; + int external; /* metadata is + * managed externally */ + char metadata_type[17]; /* externally set*/ int chunk_size; time_t ctime, utime; int level, layout; -- cgit v1.2.3