[POWERPC] Move allocation of cell IOMMU pad page
There's no need to allocate the pad page unless we're going to actually
use it - so move the allocation to where we know we're going to use it.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/powerpc/platforms/cell/iommu.c b/arch/powerpc/platforms/cell/iommu.c
index 555d264..8e57e1a 100644
--- a/arch/powerpc/platforms/cell/iommu.c
+++ b/arch/powerpc/platforms/cell/iommu.c
@@ -344,12 +344,6 @@
iommu->ptab = page_address(page);
memset(iommu->ptab, 0, ptab_size);
- /* allocate a bogus page for the end of each mapping */
- page = alloc_pages_node(iommu->nid, GFP_KERNEL, 0);
- BUG_ON(!page);
- iommu->pad_page = page_address(page);
- clear_page(iommu->pad_page);
-
/* number of pages needed for a page table */
n_pte_pages = (pages_per_segment *
sizeof(unsigned long)) >> IOMMU_PAGE_SHIFT;
@@ -463,6 +457,7 @@
unsigned long pte_offset)
{
struct iommu_window *window;
+ struct page *page;
u32 ioid;
ioid = cell_iommu_get_ioid(np);
@@ -501,6 +496,11 @@
* This code also assumes that we have a window that starts at 0,
* which is the case on all spider based blades.
*/
+ page = alloc_pages_node(iommu->nid, GFP_KERNEL, 0);
+ BUG_ON(!page);
+ iommu->pad_page = page_address(page);
+ clear_page(iommu->pad_page);
+
__set_bit(0, window->table.it_map);
tce_build_cell(&window->table, window->table.it_offset, 1,
(unsigned long)iommu->pad_page, DMA_TO_DEVICE);