From fb695c74aa43c9bdc67b3079cddec1cc8e1b913e Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Fri, 1 Feb 2019 20:29:29 +0100 Subject: [PATCH] block: Do not copy exact_filename from format file If a format BDS's file BDS is in turn a format BDS, we cannot simply use the same filename, because when opening a BDS tree based on a filename alone, qemu will create only one format node on top of one protocol node (disregarding a potential backing file). Signed-off-by: Max Reitz Reviewed-by: Alberto Garcia Message-id: 20190201192935.18394-26-mreitz@redhat.com Signed-off-by: Max Reitz --- block.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/block.c b/block.c index 23869623ea..9d9929e1a2 100644 --- a/block.c +++ b/block.c @@ -5731,9 +5731,21 @@ void bdrv_refresh_filename(BlockDriverState *bs) bs->exact_filename[0] = '\0'; - /* If no specific options have been given for this BDS, the filename of - * the underlying file should suffice for this one as well */ - if (bs->file->bs->exact_filename[0] && !generate_json_filename) { + /* + * We can use the underlying file's filename if: + * - it has a filename, + * - the file is a protocol BDS, and + * - opening that file (as this BDS's format) will automatically create + * the BDS tree we have right now, that is: + * - the user did not significantly change this BDS's behavior with + * some explicit (strong) options + * - no non-file child of this BDS has been overridden by the user + * Both of these conditions are represented by generate_json_filename. + */ + if (bs->file->bs->exact_filename[0] && + bs->file->bs->drv->bdrv_file_open && + !generate_json_filename) + { strcpy(bs->exact_filename, bs->file->bs->exact_filename); } }