[PATCH] IB/mthca: allocate correct number of doorbell pages

Doorbell record pages are allocated in HCA page size chunks (always 4096
bytes), so we need to divide by 4096 and not PAGE_SIZE when figuring out how
many pages we'll need space for.
Signed-off-by: Roland Dreier <roland@topspin.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/infiniband/hw/mthca/mthca_memfree.c

@@ -446,7 +446,7 @@ int mthca_init_db_tab(struct mthca_dev *dev)
 
 	init_MUTEX(&dev->db_tab->mutex);
 
-	dev->db_tab->npages     = dev->uar_table.uarc_size / PAGE_SIZE;
+	dev->db_tab->npages     = dev->uar_table.uarc_size / 4096;
 	dev->db_tab->max_group1 = 0;
 	dev->db_tab->min_group2 = dev->db_tab->npages - 1;