diff options
author | NeilBrown <neilb@suse.de> | 2011-05-11 15:52:21 +1000 |
---|---|---|
committer | NeilBrown <neilb@suse.de> | 2011-05-11 15:52:21 +1000 |
commit | b098636cf04c89db4036fedc778da0acc666ad1a (patch) | |
tree | 11a970bdc482b4e5cb2211eefb9a71ae34355bd3 /drivers/md | |
parent | ab9d47e990c12c11cc95ed1247a3782234a7e33a (diff) |
md: allow resync_start to be set while an array is active.
The sysfs attribute 'resync_start' (known internally as recovery_cp),
records where a resync is up to. A value of 0 means the array is
not known to be in-sync at all. A value of MaxSector means the array
is believed to be fully in-sync.
When the size of member devices of an array (RAID1,RAID4/5/6) is
increased, the array can be increased to match. This process sets
resync_start to the old end-of-device offset so that the new part of
the array gets resynced.
However with RAID1 (and RAID6) a resync is not technically necessary
and may be undesirable. So it would be good if the implied resync
after the array is resized could be avoided.
So: change 'resync_start' so the value can be changed while the array
is active, and as a precaution only allow it to be changed while
resync/recovery is 'frozen'. Changing it once resync has started is
not going to be useful anyway.
This allows the array to be resized without a resync by:
write 'frozen' to 'sync_action'
write new size to 'component_size' (this will set resync_start)
write 'none' to 'resync_start'
write 'idle' to 'sync_action'.
Also slightly improve some tests on recovery_cp when resizing
raid1/raid5. Now that an arbitrary value could be set we should be
more careful in our tests.
Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'drivers/md')
-rw-r--r-- | drivers/md/md.c | 2 | ||||
-rw-r--r-- | drivers/md/raid1.c | 2 | ||||
-rw-r--r-- | drivers/md/raid5.c | 3 |
3 files changed, 4 insertions, 3 deletions
diff --git a/drivers/md/md.c b/drivers/md/md.c index 5469ae35ee1..aa640a85bb2 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3324,7 +3324,7 @@ resync_start_store(mddev_t *mddev, const char *buf, size_t len) char *e; unsigned long long n = simple_strtoull(buf, &e, 10); - if (mddev->pers) + if (mddev->pers && !test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) return -EBUSY; if (cmd_match(buf, "none")) n = MaxSector; diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 779abbd2bb1..5d096096f95 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -2061,7 +2061,7 @@ static int raid1_resize(mddev_t *mddev, sector_t sectors) set_capacity(mddev->gendisk, mddev->array_sectors); revalidate_disk(mddev->gendisk); if (sectors > mddev->dev_sectors && - mddev->recovery_cp == MaxSector) { + mddev->recovery_cp > mddev->dev_sectors) { mddev->recovery_cp = mddev->dev_sectors; set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); } diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 51af7f3bfe5..34dd54539f7 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5389,7 +5389,8 @@ static int raid5_resize(mddev_t *mddev, sector_t sectors) return -EINVAL; set_capacity(mddev->gendisk, mddev->array_sectors); revalidate_disk(mddev->gendisk); - if (sectors > mddev->dev_sectors && mddev->recovery_cp == MaxSector) { + if (sectors > mddev->dev_sectors && + mddev->recovery_cp > mddev->dev_sectors) { mddev->recovery_cp = mddev->dev_sectors; set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); } |