diff options
| author | NeilBrown <neilb@suse.de> | 2008-02-06 01:39:52 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2008-02-06 10:41:18 -0800 |
| commit | c620727779f7cc8ea96efb71f0651a26349e59c1 (patch) | |
| tree | 777abdad9c9ef10cb4df5c0efc736e6c64851ed8 /drivers/md/raid5.c | |
| parent | c303da6d713b87b7b3f999f5acce8ecc76ff1adb (diff) | |
md: allow a maximum extent to be set for resyncing
This allows userspace to control resync/reshape progress and synchronise it
with other activities, such as shared access in a SAN, or backing up critical
sections during a tricky reshape.
Writing a number of sectors (which must be a multiple of the chunk size if
such is meaningful) causes a resync to pause when it gets to that point.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/md/raid5.c')
| -rw-r--r-- | drivers/md/raid5.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 388a974d63ef..e946de6f46bc 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3698,6 +3698,25 @@ static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped release_stripe(sh); first_sector += STRIPE_SECTORS; } + /* If this takes us to the resync_max point where we have to pause, + * then we need to write out the superblock. + */ + sector_nr += conf->chunk_size>>9; + if (sector_nr >= mddev->resync_max) { + /* Cannot proceed until we've updated the superblock... */ + wait_event(conf->wait_for_overlap, + atomic_read(&conf->reshape_stripes) == 0); + mddev->reshape_position = conf->expand_progress; + set_bit(MD_CHANGE_DEVS, &mddev->flags); + md_wakeup_thread(mddev->thread); + wait_event(mddev->sb_wait, + !test_bit(MD_CHANGE_DEVS, &mddev->flags) + || kthread_should_stop()); + spin_lock_irq(&conf->device_lock); + conf->expand_lo = mddev->reshape_position; + spin_unlock_irq(&conf->device_lock); + wake_up(&conf->wait_for_overlap); + } return conf->chunk_size>>9; } @@ -3734,6 +3753,12 @@ static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *ski if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) return reshape_request(mddev, sector_nr, skipped); + /* No need to check resync_max as we never do more than one + * stripe, and as resync_max will always be on a chunk boundary, + * if the check in md_do_sync didn't fire, there is no chance + * of overstepping resync_max here + */ + /* if there is too many failed drives and we are trying * to resync, then assert that we are finished, because there is * nothing we can do. |