[S390] DEBUG_PAGEALLOC support for s390.

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

1 files changed, 27 insertions, 0 deletions

diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index b234bb4..983ec6e 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -167,6 +167,33 @@ void __init mem_init(void)
 	       PFN_ALIGN((unsigned long)&_eshared) - 1);
 }
 
+#ifdef CONFIG_DEBUG_PAGEALLOC
+void kernel_map_pages(struct page *page, int numpages, int enable)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	unsigned long address;
+	int i;
+
+	for (i = 0; i < numpages; i++) {
+		address = page_to_phys(page + i);
+		pgd = pgd_offset_k(address);
+		pud = pud_offset(pgd, address);
+		pmd = pmd_offset(pud, address);
+		pte = pte_offset_kernel(pmd, address);
+		if (!enable) {
+			ptep_invalidate(address, pte);
+			continue;
+		}
+		*pte = mk_pte_phys(address, __pgprot(_PAGE_TYPE_RW));
+		/* Flush cpu write queue. */
+		mb();
+	}
+}
+#endif
+
 void free_initmem(void)
 {
         unsigned long addr;