CTL_MS_SECTOR_BUFFER_t *ctl_ms_read_lock_sector(CTL_MS_VOLUME_t *vol, CTL_MS_LBA_t sector);
ctl_ms_read_lock_sector reads sector sector from volume vol into the sector cache if not already present. Sectors will be flushed to the media as necessary in order to make space in the cache for the requested sector. ctl_ms_read_lock_sector will return zero if there is an error reading the sector from the volume or if there was an error flushing a sector in order to make room for this one.