virtio: Fix vring_init/vring_size to take unsigned long

Using unsigned int resulted in silent truncation of the upper 32-bit
on x86_64 resulting in an OOPS since the ring was being initialized
wrong.

Please reconsider my previous patch to just use PAGE_ALIGN().  Open
coding this sort of stuff, no matter how simple it seems, is just
asking for this sort of trouble.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

include/linux/virtio_ring.h

@@ -89,7 +89,7 @@ struct vring {
  * };
  */
 static inline void vring_init(struct vring *vr, unsigned int num, void *p,
-			      unsigned int pagesize)
+			      unsigned long pagesize)
 {
 	vr->num = num;
 	vr->desc = p;
@@ -98,7 +98,7 @@ static inline void vring_init(struct vring *vr, unsigned int num, void *p,
 			    & ~(pagesize - 1));
 }
 
-static inline unsigned vring_size(unsigned int num, unsigned int pagesize)
+static inline unsigned vring_size(unsigned int num, unsigned long pagesize)
 {
 	return ((sizeof(struct vring_desc) * num + sizeof(__u16) * (2 + num)
 		 + pagesize - 1) & ~(pagesize - 1))