block: Use backing format driver during image creation

The backing format should be honored during image creation.  For some
reason we currently use the image format to open the backing file.  This
fails when the backing file has a different format than the image being
created.  Keep the image and backing format drivers completely separate.

Also print the backing filename if there is an error opening the backing
file instead of the image filename.

Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Acked-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2011-01-24 09:32:20 +00:00 committed by Kevin Wolf
parent 850ec1133b
commit 96df67d1c3

View file

@ -2778,6 +2778,7 @@ int bdrv_img_create(const char *filename, const char *fmt,
QEMUOptionParameter *backing_fmt, *backing_file;
BlockDriverState *bs = NULL;
BlockDriver *drv, *proto_drv;
BlockDriver *backing_drv = NULL;
int ret = 0;
/* Find driver and parse its options */
@ -2846,7 +2847,8 @@ int bdrv_img_create(const char *filename, const char *fmt,
backing_fmt = get_option_parameter(param, BLOCK_OPT_BACKING_FMT);
if (backing_fmt && backing_fmt->value.s) {
if (!bdrv_find_format(backing_fmt->value.s)) {
backing_drv = bdrv_find_format(backing_fmt->value.s);
if (!backing_drv) {
error_report("Unknown backing file format '%s'",
backing_fmt->value.s);
ret = -EINVAL;
@ -2863,9 +2865,9 @@ int bdrv_img_create(const char *filename, const char *fmt,
bs = bdrv_new("");
ret = bdrv_open(bs, backing_file->value.s, flags, drv);
ret = bdrv_open(bs, backing_file->value.s, flags, backing_drv);
if (ret < 0) {
error_report("Could not open '%s'", filename);
error_report("Could not open '%s'", backing_file->value.s);
goto out;
}
bdrv_get_geometry(bs, &size);