diff options
Diffstat (limited to 'block.c')
| -rw-r--r-- | block.c | 78 |
1 files changed, 54 insertions, 24 deletions
diff --git a/block.c b/block.c index ca11078cd2..acd35cb0cb 100644 --- a/block.c +++ b/block.c @@ -92,7 +92,7 @@ static void bdrv_remove_filter_or_cow_child(BlockDriverState *bs, static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, - Transaction *set_backings_tran, Error **errp); + Transaction *change_child_tran, Error **errp); static void bdrv_reopen_commit(BDRVReopenState *reopen_state); static void bdrv_reopen_abort(BDRVReopenState *reopen_state); @@ -4148,6 +4148,10 @@ int bdrv_reopen_multiple(BlockReopenQueue *bs_queue, Error **errp) refresh_list = bdrv_topological_dfs(refresh_list, found, state->old_backing_bs); } + if (state->old_file_bs) { + refresh_list = bdrv_topological_dfs(refresh_list, found, + state->old_file_bs); + } } /* @@ -4240,64 +4244,81 @@ int bdrv_reopen_set_read_only(BlockDriverState *bs, bool read_only, * * Return 0 on success, otherwise return < 0 and set @errp. */ -static int bdrv_reopen_parse_backing(BDRVReopenState *reopen_state, - Transaction *set_backings_tran, - Error **errp) +static int bdrv_reopen_parse_file_or_backing(BDRVReopenState *reopen_state, + bool is_backing, Transaction *tran, + Error **errp) { BlockDriverState *bs = reopen_state->bs; - BlockDriverState *new_backing_bs; + BlockDriverState *new_child_bs; + BlockDriverState *old_child_bs = is_backing ? child_bs(bs->backing) : + child_bs(bs->file); + const char *child_name = is_backing ? "backing" : "file"; QObject *value; const char *str; - value = qdict_get(reopen_state->options, "backing"); + value = qdict_get(reopen_state->options, child_name); if (value == NULL) { return 0; } switch (qobject_type(value)) { case QTYPE_QNULL: - new_backing_bs = NULL; + assert(is_backing); /* The 'file' option does not allow a null value */ + new_child_bs = NULL; break; case QTYPE_QSTRING: str = qstring_get_str(qobject_to(QString, value)); - new_backing_bs = bdrv_lookup_bs(NULL, str, errp); - if (new_backing_bs == NULL) { + new_child_bs = bdrv_lookup_bs(NULL, str, errp); + if (new_child_bs == NULL) { return -EINVAL; - } else if (bdrv_recurse_has_child(new_backing_bs, bs)) { - error_setg(errp, "Making '%s' a backing file of '%s' " - "would create a cycle", str, bs->node_name); + } else if (bdrv_recurse_has_child(new_child_bs, bs)) { + error_setg(errp, "Making '%s' a %s child of '%s' would create a " + "cycle", str, child_name, bs->node_name); return -EINVAL; } break; default: - /* 'backing' does not allow any other data type */ + /* + * The options QDict has been flattened, so 'backing' and 'file' + * do not allow any other data type here. + */ g_assert_not_reached(); } - if (bs->backing) { - if (bdrv_skip_implicit_filters(bs->backing->bs) == new_backing_bs) { + if (old_child_bs == new_child_bs) { + return 0; + } + + if (old_child_bs) { + if (bdrv_skip_implicit_filters(old_child_bs) == new_child_bs) { return 0; } - if (bs->backing->bs->implicit) { - error_setg(errp, "Cannot change backing link if '%s' has " - "an implicit backing file", bs->node_name); + if (old_child_bs->implicit) { + error_setg(errp, "Cannot replace implicit %s child of %s", + child_name, bs->node_name); return -EPERM; } } - if (bs->drv->is_filter && !bs->backing) { + if (bs->drv->is_filter && !old_child_bs) { /* * Filters always have a file or a backing child, so we are trying to * change wrong child */ error_setg(errp, "'%s' is a %s filter node that does not support a " - "backing child", bs->node_name, bs->drv->format_name); + "%s child", bs->node_name, bs->drv->format_name, child_name); return -EINVAL; } - reopen_state->old_backing_bs = bs->backing ? bs->backing->bs : NULL; - return bdrv_set_backing_noperm(bs, new_backing_bs, set_backings_tran, errp); + if (is_backing) { + reopen_state->old_backing_bs = old_child_bs; + } else { + reopen_state->old_file_bs = old_child_bs; + } + + return bdrv_set_file_or_backing_noperm(bs, new_child_bs, is_backing, + tran, errp); } /* @@ -4319,7 +4340,7 @@ static int bdrv_reopen_parse_backing(BDRVReopenState *reopen_state, */ static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, BlockReopenQueue *queue, - Transaction *set_backings_tran, Error **errp) + Transaction *change_child_tran, Error **errp) { int ret = -1; int old_flags; @@ -4439,12 +4460,21 @@ static int bdrv_reopen_prepare(BDRVReopenState *reopen_state, * either a reference to an existing node (using its node name) * or NULL to simply detach the current backing file. */ - ret = bdrv_reopen_parse_backing(reopen_state, set_backings_tran, errp); + ret = bdrv_reopen_parse_file_or_backing(reopen_state, true, + change_child_tran, errp); if (ret < 0) { goto error; } qdict_del(reopen_state->options, "backing"); + /* Allow changing the 'file' option. In this case NULL is not allowed */ + ret = bdrv_reopen_parse_file_or_backing(reopen_state, false, + change_child_tran, errp); + if (ret < 0) { + goto error; + } + qdict_del(reopen_state->options, "file"); + /* 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) */ |