Function vdev_raidz_cksum_finish

freebsd/contrib/openzfs/module/zfs/vdev_raidz.c:210–295

}

static void
vdev_raidz_cksum_finish(zio_cksum_report_t *zcr, const abd_t *good_data)
{
	raidz_map_t *rm = zcr->zcr_cbdata;
	const size_t c = zcr->zcr_cbinfo;
	size_t x, offset;

	if (good_data == NULL) {
		zfs_ereport_finish_checksum(zcr, NULL, NULL, B_FALSE);
		return;
	}

	ASSERT3U(rm->rm_nrows, ==, 1);
	raidz_row_t *rr = rm->rm_row[0];

	const abd_t *good = NULL;
	const abd_t *bad = rr->rr_col[c].rc_abd;

	if (c < rr->rr_firstdatacol) {
		/*
		 * The first time through, calculate the parity blocks for
		 * the good data (this relies on the fact that the good
		 * data never changes for a given logical ZIO)
		 */
		if (rr->rr_col[0].rc_gdata == NULL) {
			abd_t *bad_parity[VDEV_RAIDZ_MAXPARITY];

			/*
			 * Set up the rr_col[]s to generate the parity for
			 * good_data, first saving the parity bufs and
			 * replacing them with buffers to hold the result.
			 */
			for (x = 0; x < rr->rr_firstdatacol; x++) {
				bad_parity[x] = rr->rr_col[x].rc_abd;
				rr->rr_col[x].rc_abd = rr->rr_col[x].rc_gdata =
				    abd_alloc_sametype(rr->rr_col[x].rc_abd,
				    rr->rr_col[x].rc_size);
			}

			/* fill in the data columns from good_data */
			offset = 0;
			for (; x < rr->rr_cols; x++) {
				abd_put(rr->rr_col[x].rc_abd);

				rr->rr_col[x].rc_abd =
				    abd_get_offset_size((abd_t *)good_data,
				    offset, rr->rr_col[x].rc_size);
				offset += rr->rr_col[x].rc_size;
			}

			/*
			 * Construct the parity from the good data.
			 */
			vdev_raidz_generate_parity_row(rm, rr);

			/* restore everything back to its original state */
			for (x = 0; x < rr->rr_firstdatacol; x++)
				rr->rr_col[x].rc_abd = bad_parity[x];