[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>
---
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.
+ *
* The @disk parameter is either an unambiguous source name of the
* block device (the <source file='...'/> sub-element, such as
* "/path/to/image"), or (since 0.9.5) the device target shorthand
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index fa9d356e15..327553f6d7 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -2949,9 +2949,12 @@ static const vshCmdOptDef opts_blockresize[] = {
},
{.name = "size",
.type = VSH_OT_INT,
- .flags = VSH_OFLAG_REQ,
.help = N_("New size of the block device, as scaled integer (default
KiB)")
},
+ {.name = "capacity",
+ .type = VSH_OT_BOOL,
+ .help = N_("resize to capacity of source (block device)")
+ },
{.name = NULL}
};
@@ -2963,6 +2966,11 @@ cmdBlockresize(vshControl *ctl, const vshCmd *cmd)
unsigned long long size = 0;
unsigned int flags = 0;
+ VSH_ALTERNATIVE_OPTIONS("size", "capacity");
+
+ if (vshCommandOptBool(cmd, "capacity"))
+ flags |= VIR_DOMAIN_BLOCK_RESIZE_CAPACITY;
+
if (vshCommandOptStringReq(ctl, cmd, "path", (const char **) &path)
< 0)
return false;
--
2.43.0