generic: make PFN_PHYS explicitly return phys_addr_t

PFN_PHYS, as its name suggests, turns a pfn into a physical address.
However, it is a macro which just operates on its argument without
modifying its type. pfns are typed unsigned long, but an unsigned
long may not be long enough to hold a physical address (32-bit systems
with more than 32 bits of physcial address).

Make sure we cast to phys_addr_t to return a complete result.

Signed-off-by: Jeremy Fitzhardinge <[e-mail]>
Signed-off-by: Ingo Molnar <[e-mail]>

arch/m32r/mm/discontig.c

···
 				initrd_start, INITRD_SIZE);
 		} else {
 			printk("initrd extends beyond end of memory "
-				"(0x%08lx > 0x%08lx)\ndisabling initrd\n",
+				"(0x%08lx > 0x%08llx)\ndisabling initrd\n",
 				INITRD_START + INITRD_SIZE,
-				PFN_PHYS(max_low_pfn));
+			        (unsigned long long)PFN_PHYS(max_low_pfn));
 
 			initrd_start = 0;
 		}

include/asm-x86/xen/page.h

···
 static inline xmaddr_t phys_to_machine(xpaddr_t phys)
 {
 	unsigned offset = phys.paddr & ~PAGE_MASK;
-	return XMADDR(PFN_PHYS((u64)pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset);
+	return XMADDR(PFN_PHYS(pfn_to_mfn(PFN_DOWN(phys.paddr))) | offset);
 }
 
 static inline xpaddr_t machine_to_phys(xmaddr_t machine)
 {
 	unsigned offset = machine.maddr & ~PAGE_MASK;
-	return XPADDR(PFN_PHYS((u64)mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
+	return XPADDR(PFN_PHYS(mfn_to_pfn(PFN_DOWN(machine.maddr))) | offset);
 }
 
 /*

include/linux/pfn.h

···
 #ifndef _LINUX_PFN_H_
 #define _LINUX_PFN_H_
 
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+#endif
+
 #define PFN_ALIGN(x)	(((unsigned long)(x) + (PAGE_SIZE - 1)) & PAGE_MASK)
 #define PFN_UP(x)	(((x) + PAGE_SIZE-1) >> PAGE_SHIFT)
 #define PFN_DOWN(x)	((x) >> PAGE_SHIFT)
-#define PFN_PHYS(x)	((x) << PAGE_SHIFT)
+#define PFN_PHYS(x)	((phys_addr_t)(x) << PAGE_SHIFT)
 
 #endif