Re: [PATCH 05/10] virDomainBlockResize: Introduce VIR_DOMAIN_BLOCK_RESIZE_CAPACITY

Allow users to easily resize 'raw' images on block devices to the full capacity of the block device. Obviously this won't work on file-backed storage (filling the remaining capacity is most likely wrong) or for formats with metadata due to the overhead. Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; --- docs/manpages/virsh.rst | 6 +++++- include/libvirt/libvirt-domain.h | 1 + src/libvirt-domain.c | 5 +++++ tools/virsh-domain.c | 10 +++++++++- 4 files changed, 20 insertions(+), 2 deletions(-) diff --git a/docs/manpages/virsh.rst b/docs/manpages/virsh.rst index 3e7a4c6c22..ed1027e133 100644 --- a/docs/manpages/virsh.rst +++ b/docs/manpages/virsh.rst @@ -1421,7 +1421,7 @@ blockresize :: - blockresize domain path size + blockresize domain path ([size] | [--capacity]) Resize a block device of domain while the domain is running, *path* specifies the absolute path of the block device; it corresponds @@ -1429,6 +1429,10 @@ to a unique target name (<target dev='name'/>) or source file (<source file='name'/>) for one of the disk devices attached to *domain* (see also ``domblklist`` for listing these names). +For image formats without metadata (raw) stored inside fixed-size storage (e.g. +block devices) the --capacity flag can be used to resize the device to the +full size of the backing device. + *size* is a scaled integer (see ``NOTES`` above) which defaults to KiB (blocks of 1024 bytes) if there is no suffix. You must use a suffix of "B" to get bytes (note that for historical reasons, this differs from diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h index a1902546bb..30cce85b29 100644 --- a/include/libvirt/libvirt-domain.h +++ b/include/libvirt/libvirt-domain.h @@ -2172,6 +2172,7 @@ int virDomainBlockPeek (virDomainPtr dom, */ typedef enum { VIR_DOMAIN_BLOCK_RESIZE_BYTES = 1 << 0, /* size in bytes instead of KiB (Since: 0.9.11) */ + VIR_DOMAIN_BLOCK_RESIZE_CAPACITY = 1 << 1, /* resize to full the capacity of the source (Since: 10.0.0) */ } virDomainBlockResizeFlags; int virDomainBlockResize (virDomainPtr dom, diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c index 77a9682ecb..94e5672ed8 100644 --- a/src/libvirt-domain.c +++ b/src/libvirt-domain.c @@ -6388,6 +6388,11 @@ virDomainBlockPeek(virDomainPtr dom, * size. Depending on the file format, the hypervisor may round up * to the next alignment boundary. * + * If @flag contains VIR_DOMAIN_BLOCK_RESIZE_CAPACITY (since 10.0.0) the + * hypervisor will resize the guest block device to fully fill the source, + * ignoring @size. This is possible only for image formats with no metadata + * ('raw') and for source devices with limited capacity such as block devices. + *