diff options
| -rw-r--r-- | block/qcow2-bitmap.c | 49 | ||||
| -rw-r--r-- | block/qcow2.c | 2 | ||||
| -rw-r--r-- | block/qcow2.h | 3 |
3 files changed, 37 insertions, 17 deletions
diff --git a/block/qcow2-bitmap.c b/block/qcow2-bitmap.c index ebc1afccd3..f7dfb40256 100644 --- a/block/qcow2-bitmap.c +++ b/block/qcow2-bitmap.c @@ -1440,7 +1440,32 @@ out: return ret; } -void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp) +/* + * qcow2_store_persistent_dirty_bitmaps + * + * Stores persistent BdrvDirtyBitmap objects. + * + * @release_stored: if true, release BdrvDirtyBitmap's after storing to the + * image. This is used in two cases, both via qcow2_inactivate: + * 1. bdrv_close: It's correct to remove bitmaps on close. + * 2. migration: If bitmaps are migrated through migration channel via + * 'dirty-bitmaps' migration capability they are not handled by this code. + * Otherwise, it's OK to drop BdrvDirtyBitmap's and reload them on + * invalidation. + * + * Anyway, it's correct to remove BdrvDirtyBitmap's on inactivation, as + * inactivation means that we lose control on disk, and therefore on bitmaps, + * we should sync them and do not touch more. + * + * Contrariwise, we don't want to release any bitmaps on just reopen-to-ro, + * when we need to store them, as image is still under our control, and it's + * good to keep all the bitmaps in read-only mode. Moreover, keeping them + * read-only is correct because this is what would happen if we opened the node + * readonly to begin with, and whether we opened directly or reopened to that + * state shouldn't matter for the state we get afterward. + */ +void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, + bool release_stored, Error **errp) { BdrvDirtyBitmap *bitmap; BDRVQcow2State *s = bs->opaque; @@ -1551,20 +1576,14 @@ void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp) g_free(tb); } - QSIMPLEQ_FOREACH(bm, bm_list, entry) { - /* For safety, we remove bitmap after storing. - * We may be here in two cases: - * 1. bdrv_close. It's ok to drop bitmap. - * 2. inactivation. It means migration without 'dirty-bitmaps' - * capability, so bitmaps are not marked with - * BdrvDirtyBitmap.migration flags. It's not bad to drop them too, - * and reload on invalidation. - */ - if (bm->dirty_bitmap == NULL) { - continue; - } + if (release_stored) { + QSIMPLEQ_FOREACH(bm, bm_list, entry) { + if (bm->dirty_bitmap == NULL) { + continue; + } - bdrv_release_dirty_bitmap(bm->dirty_bitmap); + bdrv_release_dirty_bitmap(bm->dirty_bitmap); + } } success: @@ -1592,7 +1611,7 @@ int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp) BdrvDirtyBitmap *bitmap; Error *local_err = NULL; - qcow2_store_persistent_dirty_bitmaps(bs, &local_err); + qcow2_store_persistent_dirty_bitmaps(bs, false, &local_err); if (local_err != NULL) { error_propagate(errp, local_err); return -EINVAL; diff --git a/block/qcow2.c b/block/qcow2.c index 7062eccaee..53a025703e 100644 --- a/block/qcow2.c +++ b/block/qcow2.c @@ -2503,7 +2503,7 @@ static int qcow2_inactivate(BlockDriverState *bs) int ret, result = 0; Error *local_err = NULL; - qcow2_store_persistent_dirty_bitmaps(bs, &local_err); + qcow2_store_persistent_dirty_bitmaps(bs, true, &local_err); if (local_err != NULL) { result = -EINVAL; error_reportf_err(local_err, "Lost persistent bitmaps during " diff --git a/block/qcow2.h b/block/qcow2.h index 23a9898a54..5cccd87162 100644 --- a/block/qcow2.h +++ b/block/qcow2.h @@ -742,7 +742,8 @@ Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs, Error **errp); int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp); int qcow2_truncate_bitmaps_check(BlockDriverState *bs, Error **errp); -void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp); +void qcow2_store_persistent_dirty_bitmaps(BlockDriverState *bs, + bool release_stored, Error **errp); int qcow2_reopen_bitmaps_ro(BlockDriverState *bs, Error **errp); bool qcow2_co_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name, |