From 81f382f9e0b25ef56b1c0283c900b86b91a5e4c7 Mon Sep 17 00:00:00 2001 From: Jonathan Brassow Date: Tue, 22 May 2012 13:55:30 +1000 Subject: DM RAID: Record and handle missing devices Missing dm-raid devices should be recorded in the superblock When specifying the devices that compose a DM RAID array, it is possible to denote failed or missing devices with '-'s. When this occurs, we must record this in the superblock. We do this by checking if the array position's data device is missing and then forcing MD to record the superblock by setting 'MD_CHANGE_DEVS' in 'raid_resume'. If we do not cause the superblock to be rewritten by the resume function, it is possible for a stale superblock to be written by an out-going in-active table (during 'raid_dtr'). Signed-off-by: Jonathan Brassow Signed-off-by: NeilBrown --- drivers/md/dm-raid.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'drivers') diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c index ea2d90c78f78..f1797c4f09c4 100644 --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -614,16 +614,18 @@ static int read_disk_sb(struct md_rdev *rdev, int size) static void super_sync(struct mddev *mddev, struct md_rdev *rdev) { - struct md_rdev *r; + int i; uint64_t failed_devices; struct dm_raid_superblock *sb; + struct raid_set *rs = container_of(mddev, struct raid_set, md); sb = page_address(rdev->sb_page); failed_devices = le64_to_cpu(sb->failed_devices); - rdev_for_each(r, mddev) - if ((r->raid_disk >= 0) && test_bit(Faulty, &r->flags)) - failed_devices |= (1ULL << r->raid_disk); + for (i = 0; i < mddev->raid_disks; i++) + if (!rs->dev[i].data_dev || + test_bit(Faulty, &(rs->dev[i].rdev.flags))) + failed_devices |= (1ULL << i); memset(sb, 0, sizeof(*sb)); @@ -1249,6 +1251,7 @@ static void raid_resume(struct dm_target *ti) { struct raid_set *rs = ti->private; + set_bit(MD_CHANGE_DEVS, &rs->md.flags); if (!rs->bitmap_loaded) { bitmap_load(&rs->md); rs->bitmap_loaded = 1; -- cgit v1.2.2