dmapool: Validate parameters to dma_pool_create
Check that 'align' is a power of two, like the API specifies.
Align 'size' to 'align' correctly -- the current code has an off-by-one.
The ALIGN macro in kernel.h doesn't.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Acked-by: David S. Miller <davem@davemloft.net>
diff --git a/mm/dmapool.c b/mm/dmapool.c
index b5ff9ce..744d541 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -106,16 +106,17 @@
{
struct dma_pool *retval;
- if (align == 0)
+ if (align == 0) {
align = 1;
+ } else if (align & (align - 1)) {
+ return NULL;
+ }
+
if (size == 0)
return NULL;
- else if (size < align)
- size = align;
- else if ((size % align) != 0) {
- size += align + 1;
- size &= ~(align - 1);
- }
+
+ if ((size % align) != 0)
+ size = ALIGN(size, align);
if (allocation == 0) {
if (PAGE_SIZE < size)