md: fix problems with RAID6 calculations for DDF.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 25c3c29..d4ce51b 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -158,11 +158,14 @@
{
int slot;
+ if (sh->ddf_layout)
+ slot = (*count)++;
if (idx == sh->pd_idx)
return syndrome_disks;
if (idx == sh->qd_idx)
return syndrome_disks + 1;
- slot = (*count)++;
+ if (!sh->ddf_layout)
+ slot = (*count)++;
return slot;
}
@@ -727,9 +730,8 @@
srcs[slot] = sh->dev[i].page;
i = raid6_next_disk(i, disks);
} while (i != d0_idx);
- BUG_ON(count != syndrome_disks);
- return count;
+ return syndrome_disks;
}
static struct dma_async_tx_descriptor *
@@ -828,7 +830,6 @@
failb = slot;
i = raid6_next_disk(i, disks);
} while (i != d0_idx);
- BUG_ON(count != syndrome_disks);
BUG_ON(faila == failb);
if (failb < faila)
@@ -845,7 +846,7 @@
init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
ops_complete_compute, sh,
to_addr_conv(sh, percpu));
- return async_gen_syndrome(blocks, 0, count+2,
+ return async_gen_syndrome(blocks, 0, syndrome_disks+2,
STRIPE_SIZE, &submit);
} else {
struct page *dest;
@@ -1935,10 +1936,15 @@
case ALGORITHM_PARITY_N:
break;
case ALGORITHM_ROTATING_N_CONTINUE:
+ /* Like left_symmetric, but P is before Q */
if (sh->pd_idx == 0)
i--; /* P D D D Q */
- else if (i > sh->pd_idx)
- i -= 2; /* D D Q P D */
+ else {
+ /* D D Q P D */
+ if (i < sh->pd_idx)
+ i += raid_disks;
+ i -= (sh->pd_idx + 1);
+ }
break;
case ALGORITHM_LEFT_ASYMMETRIC_6:
case ALGORITHM_RIGHT_ASYMMETRIC_6: