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-rw-r--r--kernel/arch/s390/mm/pageattr.c170
1 files changed, 170 insertions, 0 deletions
diff --git a/kernel/arch/s390/mm/pageattr.c b/kernel/arch/s390/mm/pageattr.c
new file mode 100644
index 000000000..749c98407
--- /dev/null
+++ b/kernel/arch/s390/mm/pageattr.c
@@ -0,0 +1,170 @@
+/*
+ * 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/facility.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
+
+static void ipte_range(pte_t *pte, unsigned long address, int nr)
+{
+ int i;
+
+ if (test_facility(13)) {
+ __ptep_ipte_range(address, nr - 1, pte);
+ return;
+ }
+ for (i = 0; i < nr; i++) {
+ __ptep_ipte(address, pte);
+ address += PAGE_SIZE;
+ pte++;
+ }
+}
+
+void __kernel_map_pages(struct page *page, int numpages, int enable)
+{
+ unsigned long address;
+ int nr, i, j;
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ for (i = 0; i < numpages;) {
+ 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);
+ nr = (unsigned long)pte >> ilog2(sizeof(long));
+ nr = PTRS_PER_PTE - (nr & (PTRS_PER_PTE - 1));
+ nr = min(numpages - i, nr);
+ if (enable) {
+ for (j = 0; j < nr; j++) {
+ pte_val(*pte) = __pa(address);
+ address += PAGE_SIZE;
+ pte++;
+ }
+ } else {
+ ipte_range(pte, address, nr);
+ }
+ i += nr;
+ }
+}
+
+#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 */