From: Matthew Wilcox <matthew@wil.cx>
Date: Mon, 3 Dec 2007 17:10:24 +0000 (-0500)
Subject: dmapool: Validate parameters to dma_pool_create
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=399154be2dcb6a58dbde9682162c38113cf3e40b;p=linux-beck.git

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 b5ff9ce8765b..744d541df866 100644
--- a/mm/dmapool.c
+++ b/mm/dmapool.c
@@ -106,17 +106,18 @@ struct dma_pool *dma_pool_create(const char *name, struct device *dev,
 {
 	struct dma_pool *retval;
 
-	if (align == 0)
+	if (align == 0) {
 		align = 1;
-	if (size == 0)
+	} else if (align & (align - 1)) {
 		return NULL;
-	else if (size < align)
-		size = align;
-	else if ((size % align) != 0) {
-		size += align + 1;
-		size &= ~(align - 1);
 	}
 
+	if (size == 0)
+		return NULL;
+
+	if ((size % align) != 0)
+		size = ALIGN(size, align);
+
 	if (allocation == 0) {
 		if (PAGE_SIZE < size)
 			allocation = size;