diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 21 |
1 files changed, 21 insertions, 0 deletions
@@ -332,6 +332,7 @@ BlockDriverState *bdrv_new(const char *device_name) notifier_with_return_list_init(&bs->before_write_notifiers); qemu_co_queue_init(&bs->throttled_reqs[0]); qemu_co_queue_init(&bs->throttled_reqs[1]); + bs->refcnt = 1; return bs; } @@ -1566,6 +1567,9 @@ static void bdrv_move_feature_fields(BlockDriverState *bs_dest, /* dirty bitmap */ bs_dest->dirty_bitmap = bs_src->dirty_bitmap; + /* reference count */ + bs_dest->refcnt = bs_src->refcnt; + /* job */ bs_dest->in_use = bs_src->in_use; bs_dest->job = bs_src->job; @@ -4297,6 +4301,23 @@ int64_t bdrv_get_dirty_count(BlockDriverState *bs) } } +/* Get a reference to bs */ +void bdrv_ref(BlockDriverState *bs) +{ + bs->refcnt++; +} + +/* Release a previously grabbed reference to bs. + * If after releasing, reference count is zero, the BlockDriverState is + * deleted. */ +void bdrv_unref(BlockDriverState *bs) +{ + assert(bs->refcnt > 0); + if (--bs->refcnt == 0) { + bdrv_delete(bs); + } +} + void bdrv_set_in_use(BlockDriverState *bs, int in_use) { assert(bs->in_use != in_use); |