s390/page table dumper: add support for change-recording override bit

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

@@ -340,6 +340,8 @@ extern unsigned long MODULES_END;
 #define _REGION3_ENTRY_EMPTY	(_REGION_ENTRY_TYPE_R3 | _REGION_ENTRY_INV)
 
 #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_ORIGIN	~0x7ffUL/* segment table origin		    */

arch/s390/mm/dump_pagetables.c

@@ -49,10 +49,13 @@ static void print_prot(struct seq_file *m, unsigned int pr, int level)
 		{ "ASCE", "PGD", "PUD", "PMD", "PTE" };
 
 	seq_printf(m, "%s ", level_name[level]);
-	if (pr & _PAGE_INVALID)
+	if (pr & _PAGE_INVALID) {
 		seq_printf(m, "I\n");
-	else
-		seq_printf(m, "%s\n", pr & _PAGE_RO ? "RO" : "RW");
+		return;
+	}
+	seq_printf(m, "%s", pr & _PAGE_RO ? "RO " : "RW ");
+	seq_printf(m, "%s", pr & _PAGE_CO ? "CO " : "   ");
+	seq_putc(m, '\n');
 }
 
 static void note_page(struct seq_file *m, struct pg_state *st,
@@ -125,6 +128,12 @@ static void walk_pte_level(struct seq_file *m, struct pg_state *st,
 	}
 }
 
+#ifdef CONFIG_64BIT
+#define _PMD_PROT_MASK (_SEGMENT_ENTRY_RO | _SEGMENT_ENTRY_CO)
+#else
+#define _PMD_PROT_MASK 0
+#endif
+
 static void walk_pmd_level(struct seq_file *m, struct pg_state *st,
 			   pud_t *pud, unsigned long addr)
 {
@@ -137,7 +146,7 @@ static void walk_pmd_level(struct seq_file *m, struct pg_state *st,
 		pmd = pmd_offset(pud, addr);
 		if (!pmd_none(*pmd)) {
 			if (pmd_large(*pmd)) {
-				prot = pmd_val(*pmd) & _SEGMENT_ENTRY_RO;
+				prot = pmd_val(*pmd) & _PMD_PROT_MASK;
 				note_page(m, st, prot, 3);
 			} else
 				walk_pte_level(m, st, pmd, addr);
@@ -147,6 +156,12 @@ 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)
+#else
+#define _PUD_PROT_MASK 0
+#endif
+
 static void walk_pud_level(struct seq_file *m, struct pg_state *st,
 			   pgd_t *pgd, unsigned long addr)
 {
@@ -159,7 +174,7 @@ static void walk_pud_level(struct seq_file *m, struct pg_state *st,
 		pud = pud_offset(pgd, addr);
 		if (!pud_none(*pud))
 			if (pud_large(*pud)) {
-				prot = pud_val(*pud) & _PAGE_RO;
+				prot = pud_val(*pud) & _PUD_PROT_MASK;
 				note_page(m, st, prot, 2);
 			} else
 				walk_pmd_level(m, st, pud, addr);