[libvirt] [PATCH v2 0/2] FS backend VolCreateXMLFrom implementation.

The following 2 patches implement virStorageVolCreateXMLFrom for the storage driver and the FS storage backend. Changes from v1: - Mark origvol as building in driver implementation - Make sure driver is locked when relocking pool object - Simplify sparse file detection with memcmp - Allocate read buffer on the heap. Thanks, Cole Cole Robinson (2): Storage driver implementation for CreateXMLFrom VolumeCreateXMLFrom FS storage backend implementation. src/storage_backend.h | 2 + src/storage_backend_fs.c | 247 +++++++++++++++++++++++++++++++++++++++------- src/storage_driver.c | 159 +++++++++++++++++++++++++++++- 3 files changed, 369 insertions(+), 39 deletions(-)