diff options
| -rw-r--r-- | block/block-backend.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/block/block-backend.c b/block/block-backend.c index 12ef80ea17..23e727199b 100644 --- a/block/block-backend.c +++ b/block/block-backend.c @@ -822,16 +822,22 @@ BlockBackend *blk_by_public(BlockBackendPublic *public) void blk_remove_bs(BlockBackend *blk) { ThrottleGroupMember *tgm = &blk->public.throttle_group_member; - BlockDriverState *bs; BdrvChild *root; notifier_list_notify(&blk->remove_bs_notifiers, blk); if (tgm->throttle_state) { - bs = blk_bs(blk); + BlockDriverState *bs = blk_bs(blk); + + /* + * Take a ref in case blk_bs() changes across bdrv_drained_begin(), for + * example, if a temporary filter node is removed by a blockjob. + */ + bdrv_ref(bs); bdrv_drained_begin(bs); throttle_group_detach_aio_context(tgm); throttle_group_attach_aio_context(tgm, qemu_get_aio_context()); bdrv_drained_end(bs); + bdrv_unref(bs); } blk_update_root_state(blk); @@ -1705,6 +1711,7 @@ void blk_drain(BlockBackend *blk) BlockDriverState *bs = blk_bs(blk); if (bs) { + bdrv_ref(bs); bdrv_drained_begin(bs); } @@ -1714,6 +1721,7 @@ void blk_drain(BlockBackend *blk) if (bs) { bdrv_drained_end(bs); + bdrv_unref(bs); } } @@ -2044,10 +2052,13 @@ static int blk_do_set_aio_context(BlockBackend *blk, AioContext *new_context, int ret; if (bs) { + bdrv_ref(bs); + if (update_root_node) { ret = bdrv_child_try_set_aio_context(bs, new_context, blk->root, errp); if (ret < 0) { + bdrv_unref(bs); return ret; } } @@ -2057,6 +2068,8 @@ static int blk_do_set_aio_context(BlockBackend *blk, AioContext *new_context, throttle_group_attach_aio_context(tgm, new_context); bdrv_drained_end(bs); } + + bdrv_unref(bs); } blk->ctx = new_context; @@ -2326,11 +2339,13 @@ void blk_io_limits_disable(BlockBackend *blk) ThrottleGroupMember *tgm = &blk->public.throttle_group_member; assert(tgm->throttle_state); if (bs) { + bdrv_ref(bs); bdrv_drained_begin(bs); } throttle_group_unregister_tgm(tgm); if (bs) { bdrv_drained_end(bs); + bdrv_unref(bs); } } |