From 92140480ed59a006b245efd33a195fde62d1845f Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Mon, 6 Jul 2015 12:28:45 +1000 Subject: md/raid5: consider updating reshape_position at start of reshape. md/raid5 only updates ->reshape_position (which is stored in metadata and is authoritative) occasionally, but particularly when getting closed to ->resync_max as it must be correct when ->resync_max is reached. When mdadm tries to stop an array which is reshaping it will: - freeze the reshape, - set resync_max to where the reshape has reached. - unfreeze the reshape. When this happens, the reshape is aborted and then restarted. The restart doesn't check that resync_max is close, and so doesn't update ->reshape_position like it should. This results in the reshape stopping, but ->reshape_position being incorrect. So on that first call to reshape_request, make sure ->reshape_position is updated if needed. Signed-off-by: NeilBrown --- drivers/md/raid5.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index f757023fc458..256b05d1117b 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -5347,6 +5347,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk sector_t stripe_addr; int reshape_sectors; struct list_head stripes; + sector_t retn; if (sector_nr == 0) { /* If restarting in the middle, skip the initial sectors */ @@ -5362,7 +5363,8 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk mddev->curr_resync_completed = sector_nr; sysfs_notify(&mddev->kobj, NULL, "sync_completed"); *skipped = 1; - return sector_nr; + retn = sector_nr; + goto finish; } } @@ -5535,6 +5537,8 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk * then we need to write out the superblock. */ sector_nr += reshape_sectors; + retn = reshape_sectors; +finish: if ((sector_nr - mddev->curr_resync_completed) * 2 >= mddev->resync_max - mddev->curr_resync_completed) { /* Cannot proceed until we've updated the superblock... */ @@ -5560,7 +5564,7 @@ static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *sk sysfs_notify(&mddev->kobj, NULL, "sync_completed"); } ret: - return reshape_sectors; + return retn; } static inline sector_t sync_request(struct mddev *mddev, sector_t sector_nr, int *skipped) -- cgit v1.2.3