Userspace tools might have the need to release space for Extent Space
Efficient (ESE) volumes when working with such a device.
Provide the necessarry interface for such a task by implementing a new
ioctl BIODASDRAS. The ioctl uses the format_data_t data structure for
data input:
typedef struct format_data_t {
unsigned int start_unit; /* from track */
unsigned int stop_unit; /* to track */
unsigned int blksize; /* sectorsize */
unsigned int intensity;
} format_data_t;
If the intensity is set to 0x40, start_unit and stop_unit are ignored
and space for the entire volume is released. Otherwise, if intensity is
set to 0, the respective range is released (if possible).
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>