Volume close should not close underlying device until all
I/O targeting this volume are deallocated. To achieve this
a reference counter is added to volume. Counter value
matches number of I/O objects associated with volume. Counter
is freezed when volume is closed, blocking allocation of new
I/O objects.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>
There is a risk that without uuid.data pointer denitialization it will
be freed during original volume deinit, zeroing uuid.data pointer
prevents that.
Signed-off-by: Michal Rakowski <michal.rakowski@intel.com>
This pointer is used to provide optional volume specific data
from the user down to bottom volume open callback. volume_params
is provided to OCF in ocf_mngt_cache_device_config.volume_params.
Signed-off-by: Adam Rutkowski <adam.j.rutkowski@intel.com>