From 70a5afedd64c3f0d3b5feae6b40b30f3e8d13e4b Mon Sep 17 00:00:00 2001 From: Kevin Wolf Date: Mon, 20 Nov 2017 15:41:31 +0100 Subject: block: Error out on load_vm with active dirty bitmaps Loading a snapshot invalidates the bitmap. Just marking all blocks dirty is not a useful response in practice, instead the user needs to be aware that we switch to a completely different state. If they are okay with losing the dirty bitmap, they can just explicitly delete it. This effectively reverts commit 04dec3c3ae5. Signed-off-by: Kevin Wolf Reviewed-by: Eric Blake Reviewed-by: Denis V. Lunev Reviewed-by: Vladimir Sementsov-Ogievskiy Reviewed-by: John Snow --- block/snapshot.c | 15 +++------------ 1 file changed, 3 insertions(+), 12 deletions(-) diff --git a/block/snapshot.c b/block/snapshot.c index 8585599579..8cb70dbad5 100644 --- a/block/snapshot.c +++ b/block/snapshot.c @@ -182,25 +182,16 @@ int bdrv_snapshot_goto(BlockDriverState *bs, { BlockDriver *drv = bs->drv; int ret, open_ret; - int64_t len; if (!drv) { error_setg(errp, "Block driver is closed"); return -ENOMEDIUM; } - len = bdrv_getlength(bs); - if (len < 0) { - error_setg_errno(errp, -len, "Cannot get block device size"); - return len; + if (!QLIST_EMPTY(&bs->dirty_bitmaps)) { + error_setg(errp, "Device has active dirty bitmaps"); + return -EBUSY; } - /* We should set all bits in all enabled dirty bitmaps, because dirty - * bitmaps reflect active state of disk and snapshot switch operation - * actually dirties active state. - * TODO: It may make sense not to set all bits but analyze block status of - * current state and destination snapshot and do not set bits corresponding - * to both-zero or both-unallocated areas. */ - bdrv_set_dirty(bs, 0, len); if (drv->bdrv_snapshot_goto) { ret = drv->bdrv_snapshot_goto(bs, snapshot_id); -- cgit v1.2.3