[PATCH] md: support md/linear array with components greater than 2 terabytes.
linear currently uses division by the size of the smallest componenet device
to find which device a request goes to. If that smallest device is larger
than 2 terabytes, then the division will not work on some systems.
So we introduce a pre-shift, and take care not to make the hash table too
large, much like the code in raid0.
Also get rid of conf->nr_zones, which is not needed.
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/raid/linear.h b/include/linux/raid/linear.h
index e04c4fe..7eaf290 100644
--- a/include/linux/raid/linear.h
+++ b/include/linux/raid/linear.h
@@ -14,8 +14,8 @@
struct linear_private_data
{
dev_info_t **hash_table;
- dev_info_t *smallest;
- int nr_zones;
+ sector_t hash_spacing;
+ int preshift; /* shift before dividing by hash_spacing */
dev_info_t disks[0];
};