From dbecebddfa4932d1c83915bcb9b5ba5984eb91be Mon Sep 17 00:00:00 2001 From: Fam Zheng Date: Sun, 22 Sep 2013 20:05:06 +0800 Subject: block: fix backing file overriding Providing backing.file.filename doesn't override backing file as expected: $ x86_64-softmmu/qemu-system-x86_64 -drive \ file=/tmp/child.qcow2,backing.file.filename=/tmp/fake.qcow2 qemu-system-x86_64: -drive \ file=/tmp/child.qcow2,backing.file.filename=/tmp/fake.qcow2: could not open disk image /tmp/child.qcow2: Can't specify 'file' and 'filename' options at the same time With $ qemu-img info /tmp/child.qcow2 image: /tmp/child.qcow2 file format: qcow2 virtual size: 1.0G (1073741824 bytes) disk size: 196K cluster_size: 65536 backing file: /tmp/fake.qcow2 This fixes it by calling bdrv_get_full_backing_filename only if backing.file.filename is not provided. Also save the backing file name to bs->backing_file so the information is correct with HMP "info block". Signed-off-by: Fam Zheng Signed-off-by: Kevin Wolf --- block.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/block.c b/block.c index ea4956d6c7..b383b721d2 100644 --- a/block.c +++ b/block.c @@ -978,11 +978,12 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) } else if (bs->backing_file[0] == '\0' && qdict_size(options) == 0) { QDECREF(options); return 0; + } else { + bdrv_get_full_backing_filename(bs, backing_filename, + sizeof(backing_filename)); } bs->backing_hd = bdrv_new(""); - bdrv_get_full_backing_filename(bs, backing_filename, - sizeof(backing_filename)); if (bs->backing_format[0] != '\0') { back_drv = bdrv_find_format(bs->backing_format); @@ -994,6 +995,8 @@ int bdrv_open_backing_file(BlockDriverState *bs, QDict *options, Error **errp) ret = bdrv_open(bs->backing_hd, *backing_filename ? backing_filename : NULL, options, back_flags, back_drv, &local_err); + pstrcpy(bs->backing_file, sizeof(bs->backing_file), + bs->backing_hd->file->filename); if (ret < 0) { bdrv_unref(bs->backing_hd); bs->backing_hd = NULL; -- cgit v1.2.3