mn10300: drop _PAGE_FILE and pte_file()-related helpers

We've replaced remap_file_pages(2) implementation with emulation.  Nobody
creates non-linear mapping anymore.

This patch also increases the number of bits availble for swap offset.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/mn10300/include/asm/pgtable.h

@@ -134,7 +134,6 @@ extern pte_t kernel_vmalloc_ptes[(VMALLOC_END - VMALLOC_START) / PAGE_SIZE];
 #define _PAGE_NX		0			/* no-execute bit */
 
 /* If _PAGE_VALID is clear, we use these: */
-#define _PAGE_FILE		xPTEL2_C	/* set:pagecache unset:swap */
 #define _PAGE_PROTNONE		0x000		/* If not present */
 
 #define __PAGE_PROT_UWAUX	0x010
@@ -241,11 +240,6 @@ static inline int pte_young(pte_t pte)	{ return pte_val(pte) & _PAGE_ACCESSED; }
 static inline int pte_write(pte_t pte)	{ return pte_val(pte) & __PAGE_PROT_WRITE; }
 static inline int pte_special(pte_t pte){ return 0; }
 
-/*
- * The following only works if pte_present() is not true.
- */
-static inline int pte_file(pte_t pte)	{ return pte_val(pte) & _PAGE_FILE; }
-
 static inline pte_t pte_rdprotect(pte_t pte)
 {
 	pte_val(pte) &= ~(__PAGE_PROT_USER|__PAGE_PROT_UWAUX); return pte;
@@ -338,16 +332,11 @@ static inline int pte_exec_kernel(pte_t pte)
 	return 1;
 }
 
-#define PTE_FILE_MAX_BITS	30
-
-#define pte_to_pgoff(pte)	(pte_val(pte) >> 2)
-#define pgoff_to_pte(off)	__pte((off) << 2 | _PAGE_FILE)
-
 /* Encode and de-code a swap entry */
-#define __swp_type(x)			(((x).val >> 2) & 0x3f)
-#define __swp_offset(x)			((x).val >> 8)
+#define __swp_type(x)			(((x).val >> 1) & 0x3f)
+#define __swp_offset(x)			((x).val >> 7)
 #define __swp_entry(type, offset) \
-	((swp_entry_t) { ((type) << 2) | ((offset) << 8) })
+	((swp_entry_t) { ((type) << 1) | ((offset) << 7) })
 #define __pte_to_swp_entry(pte)		((swp_entry_t) { pte_val(pte) })
 #define __swp_entry_to_pte(x)		__pte((x).val)