m32r: fix pte_to_pgoff(), pgoff_to_pte() and __swp_type() macros

This patch is required to handle file-mapped or swapped-out pages
correctly.

- Fix pte_to_pgoff() and pgoff_to_pte() macros not to include
_PAGE_PROTNONE bit of PTE.
Mask value for { ACCESSED, N, (R, W, X), L, G } is not 0xef but 0x7f.
- Fix __swp_type() macro for MAX_SWAPFILES_SHIFT(=5), which is defined
in include/linux/swap.h.

* M32R TLB format

[0] [1:19] [20:23] [24:31]
+-----------------------+----+-------------+
| VPN |0000| ASID |
+-----------------------+----+-------------+
+-+---------------------+----+-+---+-+-+-+-+
|0 PPN |0000|N|AC |L|G|V| |
+-+---------------------+----+-+---+-+-+-+-+
|| RWX | |
* software bits in PTE || | +-- _PAGE_FILE | _PAGE_DIRTY
|| +---- _PAGE_PRESENT
|+---------------- _PAGE_ACCESSED
+----------------- _PAGE_PROTNONE

Signed-off-by: Hitoshi Yamamoto <[e-mail]>
Signed-off-by: Hirokazu Takata <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/asm-m32r/pgtable-2level.h

···
 #define pfn_pmd(pfn, prot)	__pmd(((pfn) << PAGE_SHIFT) | pgprot_val(prot))
 
 #define PTE_FILE_MAX_BITS	29
-#define pte_to_pgoff(pte)	(((pte_val(pte) >> 2) & 0xef) | (((pte_val(pte) >> 10)) << 7))
-#define pgoff_to_pte(off)	((pte_t) { (((off) & 0xef) << 2) | (((off) >> 7) << 10) | _PAGE_FILE })
+#define pte_to_pgoff(pte)	(((pte_val(pte) >> 2) & 0x7f) | (((pte_val(pte) >> 10)) << 7))
+#define pgoff_to_pte(off)	((pte_t) { (((off) & 0x7f) << 2) | (((off) >> 7) << 10) | _PAGE_FILE })
 
 #endif /* __KERNEL__ */
 #endif /* _ASM_M32R_PGTABLE_2LEVEL_H */

include/asm-m32r/pgtable.h

···
 #define pte_unmap_nested(pte)	do { } while (0)
 
 /* Encode and de-code a swap entry */
-#define __swp_type(x)			(((x).val >> 2) & 0x3f)
+#define __swp_type(x)			(((x).val >> 2) & 0x1f)
 #define __swp_offset(x)			((x).val >> 10)
 #define __swp_entry(type, offset)	\
 	((swp_entry_t) { ((type) << 2) | ((offset) << 10) })