From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43184) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1fnsbg-00033y-80 for qemu-devel@nongnu.org; Thu, 09 Aug 2018 17:36:33 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1fnsbb-00009K-8z for qemu-devel@nongnu.org; Thu, 09 Aug 2018 17:36:32 -0400 From: Max Reitz Date: Thu, 9 Aug 2018 23:35:22 +0200 Message-Id: <20180809213528.14738-26-mreitz@redhat.com> In-Reply-To: <20180809213528.14738-1-mreitz@redhat.com> References: <20180809213528.14738-1-mreitz@redhat.com> Subject: [Qemu-devel] [PATCH for-3.1 v10 25/31] block: Do not copy exact_filename from format file List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: qemu-devel@nongnu.org, Max Reitz , Kevin Wolf , Eric Blake , Alberto Garcia 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 --- block.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/block.c b/block.c index 2d3e07b7a7..c4aec7ea65 100644 --- a/block.c +++ b/block.c @@ -5355,9 +5355,21 @@ 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); } } -- 2.17.1