cli: introduce snapshot_policy parameter for disk device

This allows to configure snapshot behavior for each disk.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1430642

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>

man/virt-install.pod

@@ -722,6 +722,12 @@ WD-WMAP9A966149
 It defines what to do with the disk if the source file is not accessible.  See
 possible values in L<http://www.libvirt.org/formatdomain.html#elementsDisks>
 
+=item B<snapshot_policy>
+
+Defines default behavior of the disk during disk snapshots.  See possible
+values in L<http://www.libvirt.org/formatdomain.html#elementsDisks>,
+"snapshot" attribute of the <disk> element.
+
 =back
 
 See the examples section for some uses. This option deprecates -f/--file,

tests/clitest.py

@@ -626,6 +626,7 @@ c.add_valid("--disk /dev/zero")  # Referencing a local unmanaged /dev node
 c.add_valid("--disk pool=default,size=.00001")  # Building 'default' pool
 c.add_valid("--disk %(AUTOMANAGEIMG)s,size=.1")  # autocreate the pool
 c.add_valid("--disk %(NEWIMG1)s,sparse=true,size=100000000 --check disk_size=off")  # Don't warn about fully allocated file exceeding disk space
+c.add_valid("--disk %(EXISTIMG1)s,snapshot_policy=no")  # Disable snasphot for disk
 c.add_invalid("--file %(NEWIMG1)s --file-size 100000 --nonsparse")  # Nonexisting file, size too big
 c.add_invalid("--file %(NEWIMG1)s --file-size 100000")  # Huge file, sparse, but no prompting
 c.add_invalid("--file %(NEWIMG1)s")  # Nonexisting file, no size

virtinst/cli.py

@@ -2069,6 +2069,7 @@ ParserDisk.add_arg("source_host_transport", "source_host_transport")
 
 ParserDisk.add_arg("path", "path")
 ParserDisk.add_arg("device", "device")
+ParserDisk.add_arg("snapshot_policy", "snapshot_policy")
 ParserDisk.add_arg("bus", "bus")
 ParserDisk.add_arg("removable", "removable", is_onoff=True)
 ParserDisk.add_arg("driver_cache", "cache")

virtinst/devicedisk.py

@@ -468,7 +468,7 @@ class VirtualDisk(VirtualDevice):
 
 
     _XML_PROP_ORDER = [
-        "type", "device",
+        "type", "device", "snapshot_policy",
         "driver_name", "driver_type",
         "driver_cache", "driver_discard", "driver_detect_zeroes",
         "driver_io", "error_policy",
@@ -727,6 +727,7 @@ class VirtualDisk(VirtualDevice):
 
     device = XMLProperty("./@device",
                          default_cb=lambda s: s.DEVICE_DISK)
+    snapshot_policy = XMLProperty("./@snapshot")
     driver_name = XMLProperty("./driver/@name",
                               default_cb=_get_default_driver_name)
     driver_type = XMLProperty("./driver/@type",