1 files changed, 146 insertions, 0 deletions
diff --git a/arch/s390/mm/pageattr.c b/arch/s390/mm/pageattr.c
new file mode 100644
index 00000000000..8400f494623
--- /dev/null
+++ b/arch/s390/mm/pageattr.c
@@ -0,0 +1,146 @@
+/*
+ * Copyright IBM Corp. 2011
+ * Author(s): Jan Glauber <jang@linux.vnet.ibm.com>
+ */
+#include <linux/hugetlb.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <asm/cacheflush.h>
+#include <asm/pgtable.h>
+#include <asm/page.h>
+
+#if PAGE_DEFAULT_KEY
+static inline unsigned long sske_frame(unsigned long addr, unsigned char skey)
+{
+	asm volatile(".insn rrf,0xb22b0000,%[skey],%[addr],9,0"
+		     : [addr] "+a" (addr) : [skey] "d" (skey));
+	return addr;
+}
+
+void __storage_key_init_range(unsigned long start, unsigned long end)
+{
+	unsigned long boundary, size;
+
+	while (start < end) {
+		if (MACHINE_HAS_EDAT1) {
+			/* set storage keys for a 1MB frame */
+			size = 1UL << 20;
+			boundary = (start + size) & ~(size - 1);
+			if (boundary <= end) {
+				do {
+					start = sske_frame(start, PAGE_DEFAULT_KEY);
+				} while (start < boundary);
+				continue;
+			}
+		}
+		page_set_storage_key(start, PAGE_DEFAULT_KEY, 0);
+		start += PAGE_SIZE;
+	}
+}
+#endif
+
+static pte_t *walk_page_table(unsigned long addr)
+{
+	pgd_t *pgdp;
+	pud_t *pudp;
+	pmd_t *pmdp;
+	pte_t *ptep;
+
+	pgdp = pgd_offset_k(addr);
+	if (pgd_none(*pgdp))
+		return NULL;
+	pudp = pud_offset(pgdp, addr);
+	if (pud_none(*pudp) || pud_large(*pudp))
+		return NULL;
+	pmdp = pmd_offset(pudp, addr);
+	if (pmd_none(*pmdp) || pmd_large(*pmdp))
+		return NULL;
+	ptep = pte_offset_kernel(pmdp, addr);
+	if (pte_none(*ptep))
+		return NULL;
+	return ptep;
+}
+
+static void change_page_attr(unsigned long addr, int numpages,
+			     pte_t (*set) (pte_t))
+{
+	pte_t *ptep, pte;
+	int i;
+
+	for (i = 0; i < numpages; i++) {
+		ptep = walk_page_table(addr);
+		if (WARN_ON_ONCE(!ptep))
+			break;
+		pte = *ptep;
+		pte = set(pte);
+		__ptep_ipte(addr, ptep);
+		*ptep = pte;
+		addr += PAGE_SIZE;
+	}
+}
+
+int set_memory_ro(unsigned long addr, int numpages)
+{
+	change_page_attr(addr, numpages, pte_wrprotect);
+	return 0;
+}
+
+int set_memory_rw(unsigned long addr, int numpages)
+{
+	change_page_attr(addr, numpages, pte_mkwrite);
+	return 0;
+}
+
+/* not possible */
+int set_memory_nx(unsigned long addr, int numpages)
+{
+	return 0;
+}
+
+int set_memory_x(unsigned long addr, int numpages)
+{
+	return 0;
+}
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+void kernel_map_pages(struct page *page, int numpages, int enable)
+{
+	unsigned long address;
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	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_ipte(address, pte);
+			pte_val(*pte) = _PAGE_INVALID;
+			continue;
+		}
+		pte_val(*pte) = __pa(address);
+	}
+}
+
+#ifdef CONFIG_HIBERNATION
+bool kernel_page_present(struct page *page)
+{
+	unsigned long addr;
+	int cc;
+
+	addr = page_to_phys(page);
+	asm volatile(
+		"	lra	%1,0(%1)\n"
+		"	ipm	%0\n"
+		"	srl	%0,28"
+		: "=d" (cc), "+a" (addr) : : "cc");
+	return cc == 0;
+}
+#endif /* CONFIG_HIBERNATION */
+
+#endif /* CONFIG_DEBUG_PAGEALLOC */