def validate(self):
if self.base_id not in self.chain:
raise se.VolumeIsNotInChain(self.sd_id, self.img_id, self.base_id)
if self.top_id not in self.chain:
raise se.VolumeIsNotInChain(self.sd_id, self.img_id, self.top_id)
# Validate that top volume is the parent of the base.
if self.top_vol.getParent() != self.base_id:
raise se.WrongParentVolume(self.base_id, self.top_id)
if self.base_vol.isShared():
raise se.SharedVolumeNonWritable(self.base_vol)
if self.top_vol.isShared():
raise se.SharedVolumeNonWritable(self.top_vol)
def prepare(self,
rw=True,
justme=False,
chainrw=False,
setrw=False,
force=False):
"""
Prepare volume for use by consumer.
If justme is false, the entire COW chain is prepared.
Note: setrw arg may be used only by SPM flows.
"""
self.log.info("Volume: preparing volume %s/%s", self.sdUUID,
self.volUUID)
if not force:
# Cannot prepare ILLEGAL volume
if not self.isLegal():
raise se.prepareIllegalVolumeError(self.volUUID)
if rw and self.isShared():
if chainrw:
rw = False # Shared cannot be set RW
else:
raise se.SharedVolumeNonWritable(self)
if (not chainrw and rw and self.isInternal() and setrw
and not self.recheckIfLeaf()):
raise se.InternalVolumeNonWritable(self)
self.llPrepare(rw=rw, setrw=setrw)
self.updateInvalidatedSize()
try:
if justme:
return True
pvol = self.getParentVolume()
if pvol:
pvol.prepare(rw=chainrw,
justme=False,
chainrw=chainrw,
setrw=setrw)
except Exception:
self.log.error("Unexpected error", exc_info=True)
self.teardown(self.sdUUID, self.volUUID)
raise
return True
