Commit a505475b authored by Vladimir Sementsov-Ogievskiy's avatar Vladimir Sementsov-Ogievskiy Committed by Max Reitz
Browse files

block/qcow2-bitmap: fix bitmap migration 



Fix bitmap migration with dirty-bitmaps capability enabled and shared
storage. We should ignore IN_USE bitmaps in the image on target, when
migrating bitmaps through migration channel, see new comment below.

Fixes: 74da6b94
Signed-off-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191125125229.13531-2-vsementsov@virtuozzo.com
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
Signed-off-by: default avatarMax Reitz <mreitz@redhat.com>
parent 4ecc9842

block/qcow2-bitmap.c

+20 −1
Original line number Diff line number Diff line
@@ -988,7 +988,26 @@ bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp) 
    }



    QSIMPLEQ_FOREACH(bm, bm_list, entry) {

        BdrvDirtyBitmap *bitmap = load_bitmap(bs, bm, errp);

        BdrvDirtyBitmap *bitmap;



        if ((bm->flags & BME_FLAG_IN_USE) &&

            bdrv_find_dirty_bitmap(bs, bm->name))

        {

            /*

             * We already have corresponding BdrvDirtyBitmap, and bitmap in the

             * image is marked IN_USE. Firstly, this state is valid, no reason

             * to consider existing BdrvDirtyBitmap to be bad. Secondly it's

             * absolutely possible, when we do migration with shared storage

             * with dirty-bitmaps capability enabled: if the bitmap was loaded

             * from this storage before migration start, the storage will

             * of-course contain IN_USE outdated version of the bitmap, and we

             * should not load it on migration target, as we already have this

             * bitmap, being migrated.

             */

            continue;

        }



        bitmap = load_bitmap(bs, bm, errp);

        if (bitmap == NULL) {

            goto fail;

        }