const __u8 *src_buf, const int seg_sz,
const zft_position *pos, const zft_volinfo *volume);
static int zftc_seek(unsigned int new_block_pos,
const __u8 *src_buf, const int seg_sz,
const zft_position *pos, const zft_volinfo *volume);
static int zftc_seek(unsigned int new_block_pos,