md/raid5: allow for more than 2^31 chunks.
With many large drives and small chunk sizes it is possible
to create a RAID5 with more than 2^31 chunks. Make sure this
works.
Reported-by: Brett King <king.br@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@kernel.org
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index e3e9a36..20e4840 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1650,8 +1650,8 @@
int previous, int *dd_idx,
struct stripe_head *sh)
{
- long stripe;
- unsigned long chunk_number;
+ sector_t stripe;
+ sector_t chunk_number;
unsigned int chunk_offset;
int pd_idx, qd_idx;
int ddf_layout = 0;
@@ -1671,17 +1671,12 @@
*/
chunk_offset = sector_div(r_sector, sectors_per_chunk);
chunk_number = r_sector;
- BUG_ON(r_sector != chunk_number);
/*
* Compute the stripe number
*/
- stripe = chunk_number / data_disks;
-
- /*
- * Compute the data disk and parity disk indexes inside the stripe
- */
- *dd_idx = chunk_number % data_disks;
+ stripe = chunk_number;
+ *dd_idx = sector_div(stripe, data_disks);
/*
* Select the parity disk based on the user selected algorithm.
@@ -1870,14 +1865,14 @@
: conf->algorithm;
sector_t stripe;
int chunk_offset;
- int chunk_number, dummy1, dd_idx = i;
+ sector_t chunk_number;
+ int dummy1, dd_idx = i;
sector_t r_sector;
struct stripe_head sh2;
chunk_offset = sector_div(new_sector, sectors_per_chunk);
stripe = new_sector;
- BUG_ON(new_sector != stripe);
if (i == sh->pd_idx)
return 0;
@@ -1970,7 +1965,7 @@
}
chunk_number = stripe * data_disks + i;
- r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset;
+ r_sector = chunk_number * sectors_per_chunk + chunk_offset;
check = raid5_compute_sector(conf, r_sector,
previous, &dummy1, &sh2);