diff options
| -rw-r--r-- | block.c | 52 | ||||
| -rw-r--r-- | include/block/block.h | 1 |
2 files changed, 46 insertions, 7 deletions
diff --git a/block.c b/block.c index 3cd281dbcc..9698f2ad44 100644 --- a/block.c +++ b/block.c @@ -3107,9 +3107,21 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, bs_entry->state.perm = UINT64_MAX; bs_entry->state.shared_perm = 0; + /* + * If keep_old_opts is false then it means that unspecified + * options must be reset to their original value. We don't allow + * resetting 'backing' but we need to know if the option is + * missing in order to decide if we have to return an error. + */ + if (!keep_old_opts) { + bs_entry->state.backing_missing = + !qdict_haskey(options, "backing") && + !qdict_haskey(options, "backing.driver"); + } + QLIST_FOREACH(child, &bs->children, next) { - QDict *new_child_options; - char *child_key_dot; + QDict *new_child_options = NULL; + bool child_keep_old = keep_old_opts; /* reopen can only change the options of block devices that were * implicitly created and inherited options. For other (referenced) @@ -3118,13 +3130,32 @@ static BlockReopenQueue *bdrv_reopen_queue_child(BlockReopenQueue *bs_queue, continue; } - child_key_dot = g_strdup_printf("%s.", child->name); - qdict_extract_subqdict(explicit_options, NULL, child_key_dot); - qdict_extract_subqdict(options, &new_child_options, child_key_dot); - g_free(child_key_dot); + /* Check if the options contain a child reference */ + if (qdict_haskey(options, child->name)) { + const char *childref = qdict_get_try_str(options, child->name); + /* + * The current child must not be reopened if the child + * reference is null or points to a different node. + */ + if (g_strcmp0(childref, child->bs->node_name)) { + continue; + } + /* + * If the child reference points to the current child then + * reopen it with its existing set of options (note that + * it can still inherit new options from the parent). + */ + child_keep_old = true; + } else { + /* Extract child options ("child-name.*") */ + char *child_key_dot = g_strdup_printf("%s.", child->name); + qdict_extract_subqdict(explicit_options, NULL, child_key_dot); + qdict_extract_subqdict(options, &new_child_options, child_key_dot); + g_free(child_key_dot); + } bdrv_reopen_queue_child(bs_queue, child->bs, new_child_options, - child->role, options, flags, keep_old_opts); + child->role, options, flags, child_keep_old); } return bs_queue; @@ -3403,6 +3434,13 @@ int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, drv_prepared = true; + if (drv->supports_backing && reopen_state->backing_missing) { + error_setg(errp, "backing is missing for '%s'", + reopen_state->bs->node_name); + ret = -EINVAL; + goto error; + } + /* Options that are not handled are only okay if they are unchanged * compared to the old state. It is expected that some options are only * used for the initial open, but not reopen (e.g. filename) */ diff --git a/include/block/block.h b/include/block/block.h index 4b5ffffa1a..fcc61a3a19 100644 --- a/include/block/block.h +++ b/include/block/block.h @@ -187,6 +187,7 @@ typedef struct BDRVReopenState { BlockDriverState *bs; int flags; BlockdevDetectZeroesOptions detect_zeroes; + bool backing_missing; uint64_t perm, shared_perm; QDict *options; QDict *explicit_options; |