SR_META_OFFSET
off += SR_META_OFFSET;
off += SR_META_OFFSET;
off += SR_META_OFFSET;
off += SR_META_OFFSET;
error = strategy(&ofdev, F_READ, SR_META_OFFSET,
{ SR_META_OFFSET, SR_META_SIZE * DEV_BSIZE,
SR_META_OFFSET, flags);
#define SR_DATA_OFFSET (SR_META_OFFSET + SR_HEADER_SIZE)
#define SR_BOOT_OFFSET (SR_META_OFFSET + SR_META_SIZE)