[S390] protect _PAGE_SPECIAL bit against mprotect

[pandora-kernel.git] / include / asm-s390 / pgtable.h

diff --git a/include/asm-s390/pgtable.h b/include/asm-s390/pgtable.h
index 76e8a79..bd0ea19 100644 (file)
--- a/include/asm-s390/pgtable.h
+++ b/include/asm-s390/pgtable.h
@@ -129,7 +129,7 @@ extern char empty_zero_page[PAGE_SIZE];
 #define VMEM_MAX_PAGES ((VMEM_MAP_END - VMALLOC_END) / sizeof(struct page))
 #define VMEM_MAX_PFN   min(VMALLOC_START >> PAGE_SHIFT, VMEM_MAX_PAGES)
 #define VMEM_MAX_PHYS  ((VMEM_MAX_PFN << PAGE_SHIFT) & ~((16 << 20) - 1))
-#define VMEM_MAP       ((struct page *) VMALLOC_END)
+#define vmemmap                ((struct page *) VMALLOC_END)
 
 /*
  * A 31 bit pagetable entry of S390 has following format:
@@ -220,6 +220,11 @@ extern char empty_zero_page[PAGE_SIZE];
 /* Software bits in the page table entry */
 #define _PAGE_SWT      0x001           /* SW pte type bit t */
 #define _PAGE_SWX      0x002           /* SW pte type bit x */
+#define _PAGE_SPECIAL  0x004           /* SW associated with special page */
+#define __HAVE_ARCH_PTE_SPECIAL
+
+/* Set of bits not changed in pte_modify */
+#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_SPECIAL)
 
 /* Six different types of pages. */
 #define _PAGE_TYPE_EMPTY       0x400
@@ -231,6 +236,15 @@ extern char empty_zero_page[PAGE_SIZE];
 #define _PAGE_TYPE_EX_RO       0x202
 #define _PAGE_TYPE_EX_RW       0x002
 
+/*
+ * Only four types for huge pages, using the invalid bit and protection bit
+ * of a segment table entry.
+ */
+#define _HPAGE_TYPE_EMPTY      0x020   /* _SEGMENT_ENTRY_INV */
+#define _HPAGE_TYPE_NONE       0x220
+#define _HPAGE_TYPE_RO         0x200   /* _SEGMENT_ENTRY_RO  */
+#define _HPAGE_TYPE_RW         0x000
+
 /*
  * PTE type bits are rather complicated. handle_pte_fault uses pte_present,
  * pte_none and pte_file to find out the pte type WITHOUT holding the page
@@ -323,6 +337,9 @@ extern char empty_zero_page[PAGE_SIZE];
 #define _SEGMENT_ENTRY         (0)
 #define _SEGMENT_ENTRY_EMPTY   (_SEGMENT_ENTRY_INV)
 
+#define _SEGMENT_ENTRY_LARGE   0x400   /* STE-format control, large page   */
+#define _SEGMENT_ENTRY_CO      0x100   /* change-recording override   */
+
 #endif /* __s390x__ */
 
 /*
@@ -520,7 +537,7 @@ static inline int pte_file(pte_t pte)
 
 static inline int pte_special(pte_t pte)
 {
-       return 0;
+       return (pte_val(pte) & _PAGE_SPECIAL);
 }
 
 #define __HAVE_ARCH_PTE_SAME
@@ -667,7 +684,7 @@ static inline void pte_clear(struct mm_struct *mm, unsigned long addr, pte_t *pt
  */
 static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
 {
-       pte_val(pte) &= PAGE_MASK;
+       pte_val(pte) &= _PAGE_CHG_MASK;
        pte_val(pte) |= pgprot_val(newprot);
        return pte;
 }
@@ -722,6 +739,7 @@ static inline pte_t pte_mkyoung(pte_t pte)
 
 static inline pte_t pte_mkspecial(pte_t pte)
 {
+       pte_val(pte) |= _PAGE_SPECIAL;
        return pte;
 }
 
@@ -1060,8 +1078,8 @@ static inline pte_t mk_swap_pte(unsigned long type, unsigned long offset)
 
 #define kern_addr_valid(addr)   (1)
 
-extern int add_shared_memory(unsigned long start, unsigned long size);
-extern int remove_shared_memory(unsigned long start, unsigned long size);
+extern int vmem_add_mapping(unsigned long start, unsigned long size);
+extern int vmem_remove_mapping(unsigned long start, unsigned long size);
 extern int s390_enable_sie(void);
 
 /*
@@ -1069,9 +1087,6 @@ extern int s390_enable_sie(void);
  */
 #define pgtable_cache_init()   do { } while (0)
 
-#define __HAVE_ARCH_MEMMAP_INIT
-extern void memmap_init(unsigned long, int, unsigned long, unsigned long);
-
 #include <asm-generic/pgtable.h>
 
 #endif /* _S390_PAGE_H */