| Message ID | 1302706307-16627-1-git-send-email-stefanha@linux.vnet.ibm.com |
|---|---|
| State | New |
| Headers | show |
Am 13.04.2011 16:51, schrieb Stefan Hajnoczi: > From: Anthony Liguori <aliguori@us.ibm.com> > > QEMU can drop a backing file so that an image file no longer depends on > the backing file, but this feature has not been exposed in qemu-img. > This is useful in an image streaming usecase or when an image file has > been fully allocated and no reads can hit the backing file anymore. > > Since the dropping the backing file can make the image unusable, only > allow this when the unsafe flag has been set. I think it would also make sense to allow it in safe mode, it would have the same effect as rebasing onto an empty new backing file. Might take more than a one-liner, though. In case you need a workaround for older qemu-img versions, -b "" works, too (at least for qcow2). > Signed-off-by: Anthony Liguori <aliguori@us.ibm.com> > Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com> > --- > qemu-img.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) > > diff --git a/qemu-img.c b/qemu-img.c > index d9c2c12..ed5ba91 100644 > --- a/qemu-img.c > +++ b/qemu-img.c > @@ -1240,7 +1240,7 @@ static int img_rebase(int argc, char **argv) > } > } > > - if ((optind >= argc) || !out_baseimg) { > + if ((optind >= argc) || (!unsafe && !out_baseimg)) { > help(); > } > filename = argv[optind++]; Thanks, applied to the block branch. Kevin
diff --git a/qemu-img.c b/qemu-img.c index d9c2c12..ed5ba91 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -1240,7 +1240,7 @@ static int img_rebase(int argc, char **argv) } } - if ((optind >= argc) || !out_baseimg) { + if ((optind >= argc) || (!unsafe && !out_baseimg)) { help(); } filename = argv[optind++];