s390/mm: cleanup phys_to_pfn() and friends

Make page, frame, virtual and physical address conversion macros
more expressive by avoiding redundant definitions and defining
new macros using existing ones.
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>

arch/s390/include/asm/page.h

@@ -161,20 +161,20 @@ static inline int devmem_is_allowed(unsigned long pfn)
 #define __pa(x)			((unsigned long)(x))
 #define __va(x)			((void *)(unsigned long)(x))
 
-#define virt_to_pfn(kaddr)	(__pa(kaddr) >> PAGE_SHIFT)
-#define pfn_to_virt(pfn)	__va((pfn) << PAGE_SHIFT)
+#define phys_to_pfn(phys)	((phys) >> PAGE_SHIFT)
+#define pfn_to_phys(pfn)	((pfn) << PAGE_SHIFT)
+
+#define phys_to_page(phys)	pfn_to_page(phys_to_pfn(phys))
+#define page_to_phys(page)	pfn_to_phys(page_to_pfn(page))
+
+#define pfn_to_virt(pfn)	__va(pfn_to_phys(pfn))
+#define virt_to_pfn(kaddr)	(phys_to_pfn(__pa(kaddr)))
 #define pfn_to_kaddr(pfn)	pfn_to_virt(pfn)
 
 #define virt_to_page(kaddr)	pfn_to_page(virt_to_pfn(kaddr))
 #define page_to_virt(page)	pfn_to_virt(page_to_pfn(page))
 
-#define phys_to_pfn(kaddr)	((kaddr) >> PAGE_SHIFT)
-#define pfn_to_phys(pfn)	((pfn) << PAGE_SHIFT)
-
-#define phys_to_page(kaddr)	pfn_to_page(phys_to_pfn(kaddr))
-#define page_to_phys(page)	(page_to_pfn(page) << PAGE_SHIFT)
-
-#define virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
+#define virt_addr_valid(kaddr)	pfn_valid(virt_to_pfn(kaddr))
 
 #define VM_DATA_DEFAULT_FLAGS	(VM_READ | VM_WRITE | \
 				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)