s390/mm: remove change bit override support

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

arch/s390/include/asm/pgtable.h

@@ -216,7 +216,6 @@ extern unsigned long MODULES_END;
  */
 
 /* Hardware bits in the page table entry */
-#define _PAGE_CO	0x100		/* HW Change-bit override */
 #define _PAGE_PROTECT	0x200		/* HW read-only bit  */
 #define _PAGE_INVALID	0x400		/* HW invalid bit    */
 #define _PAGE_LARGE	0x800		/* Bit to mark a large pte */
@@ -233,8 +232,8 @@ extern unsigned long MODULES_END;
 #define __HAVE_ARCH_PTE_SPECIAL
 
 /* Set of bits not changed in pte_modify */
-#define _PAGE_CHG_MASK		(PAGE_MASK | _PAGE_SPECIAL | _PAGE_CO | \
-				 _PAGE_DIRTY | _PAGE_YOUNG)
+#define _PAGE_CHG_MASK		(PAGE_MASK | _PAGE_SPECIAL | _PAGE_DIRTY | \
+				 _PAGE_YOUNG)
 
 /*
  * handle_pte_fault uses pte_present, pte_none and pte_file to find out the
@@ -353,7 +352,6 @@ extern unsigned long MODULES_END;
 
 #define _REGION3_ENTRY_LARGE	0x400	/* RTTE-format control, large page  */
 #define _REGION3_ENTRY_RO	0x200	/* page protection bit		    */
-#define _REGION3_ENTRY_CO	0x100	/* change-recording override	    */
 
 /* Bits in the segment table entry */
 #define _SEGMENT_ENTRY_BITS	0xfffffffffffffe33UL
@@ -370,7 +368,6 @@ extern unsigned long MODULES_END;
 #define _SEGMENT_ENTRY_YOUNG	0x1000	/* SW segment young bit */
 #define _SEGMENT_ENTRY_SPLIT	0x0800	/* THP splitting bit */
 #define _SEGMENT_ENTRY_LARGE	0x0400	/* STE-format control, large page */
-#define _SEGMENT_ENTRY_CO	0x0100	/* change-recording override   */
 #define _SEGMENT_ENTRY_READ	0x0002	/* SW segment read bit */
 #define _SEGMENT_ENTRY_WRITE	0x0001	/* SW segment write bit */
 
@@ -887,8 +884,6 @@ static inline void set_pte_at(struct mm_struct *mm, unsigned long addr,
 		pgste = pgste_set_pte(ptep, pgste, entry);
 		pgste_set_unlock(ptep, pgste);
 	} else {
-		if (!(pte_val(entry) & _PAGE_INVALID) && MACHINE_HAS_EDAT1)
-			pte_val(entry) |= _PAGE_CO;
 		*ptep = entry;
 	}
 }

arch/s390/mm/dump_pagetables.c

@@ -54,7 +54,6 @@ static void print_prot(struct seq_file *m, unsigned int pr, int level)
 		return;
 	}
 	seq_printf(m, "%s", pr & _PAGE_PROTECT ? "RO " : "RW ");
-	seq_printf(m, "%s", pr & _PAGE_CO ? "CO " : "   ");
 	seq_putc(m, '\n');
 }
 
@@ -129,7 +128,7 @@ static void walk_pte_level(struct seq_file *m, struct pg_state *st,
 }
 
 #ifdef CONFIG_64BIT
-#define _PMD_PROT_MASK (_SEGMENT_ENTRY_PROTECT | _SEGMENT_ENTRY_CO)
+#define _PMD_PROT_MASK _SEGMENT_ENTRY_PROTECT
 #else
 #define _PMD_PROT_MASK 0
 #endif
@@ -157,7 +156,7 @@ static void walk_pmd_level(struct seq_file *m, struct pg_state *st,
 }
 
 #ifdef CONFIG_64BIT
-#define _PUD_PROT_MASK (_REGION3_ENTRY_RO | _REGION3_ENTRY_CO)
+#define _PUD_PROT_MASK _REGION3_ENTRY_RO
 #else
 #define _PUD_PROT_MASK 0
 #endif

arch/s390/mm/hugetlbpage.c

@@ -88,7 +88,7 @@ void set_huge_pte_at(struct mm_struct *mm, unsigned long addr,
 		pmd_val(pmd) &= ~_SEGMENT_ENTRY_ORIGIN;
 		pmd_val(pmd) |= pte_page(pte)[1].index;
 	} else
-		pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE | _SEGMENT_ENTRY_CO;
+		pmd_val(pmd) |= _SEGMENT_ENTRY_LARGE;
 	*(pmd_t *) ptep = pmd;
 }
 

arch/s390/mm/vmem.c

@@ -236,8 +236,7 @@ int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
 				if (!new_page)
 					goto out;
 				pmd_val(*pm_dir) = __pa(new_page) |
-					_SEGMENT_ENTRY | _SEGMENT_ENTRY_LARGE |
-					_SEGMENT_ENTRY_CO;
+					_SEGMENT_ENTRY | _SEGMENT_ENTRY_LARGE;
 				address = (address + PMD_SIZE) & PMD_MASK;
 				continue;
 			}