summaryrefslogtreecommitdiffstats
path: root/arch/s390/include/asm/kasan.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/s390/include/asm/kasan.h')
-rw-r--r--arch/s390/include/asm/kasan.h37
1 files changed, 30 insertions, 7 deletions
diff --git a/arch/s390/include/asm/kasan.h b/arch/s390/include/asm/kasan.h
index e9bf486de136..76f351bd6645 100644
--- a/arch/s390/include/asm/kasan.h
+++ b/arch/s390/include/asm/kasan.h
@@ -2,28 +2,51 @@
#ifndef __ASM_KASAN_H
#define __ASM_KASAN_H
+#include <asm/pgtable.h>
+
#ifdef CONFIG_KASAN
#define KASAN_SHADOW_SCALE_SHIFT 3
-#ifdef CONFIG_KASAN_S390_4_LEVEL_PAGING
#define KASAN_SHADOW_SIZE \
(_AC(1, UL) << (_REGION1_SHIFT - KASAN_SHADOW_SCALE_SHIFT))
-#else
-#define KASAN_SHADOW_SIZE \
- (_AC(1, UL) << (_REGION2_SHIFT - KASAN_SHADOW_SCALE_SHIFT))
-#endif
#define KASAN_SHADOW_OFFSET _AC(CONFIG_KASAN_SHADOW_OFFSET, UL)
#define KASAN_SHADOW_START KASAN_SHADOW_OFFSET
#define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE)
extern void kasan_early_init(void);
-extern void kasan_copy_shadow(pgd_t *dst);
+extern void kasan_copy_shadow_mapping(void);
extern void kasan_free_early_identity(void);
extern unsigned long kasan_vmax;
+
+/*
+ * Estimate kasan memory requirements, which it will reserve
+ * at the very end of available physical memory. To estimate
+ * that, we take into account that kasan would require
+ * 1/8 of available physical memory (for shadow memory) +
+ * creating page tables for the whole memory + shadow memory
+ * region (1 + 1/8). To keep page tables estimates simple take
+ * the double of combined ptes size.
+ *
+ * physmem parameter has to be already adjusted if not entire physical memory
+ * would be used (e.g. due to effect of "mem=" option).
+ */
+static inline unsigned long kasan_estimate_memory_needs(unsigned long physmem)
+{
+ unsigned long kasan_needs;
+ unsigned long pages;
+ /* for shadow memory */
+ kasan_needs = round_up(physmem / 8, PAGE_SIZE);
+ /* for paging structures */
+ pages = DIV_ROUND_UP(physmem + kasan_needs, PAGE_SIZE);
+ kasan_needs += DIV_ROUND_UP(pages, _PAGE_ENTRIES) * _PAGE_TABLE_SIZE * 2;
+
+ return kasan_needs;
+}
#else
static inline void kasan_early_init(void) { }
-static inline void kasan_copy_shadow(pgd_t *dst) { }
+static inline void kasan_copy_shadow_mapping(void) { }
static inline void kasan_free_early_identity(void) { }
+static inline unsigned long kasan_estimate_memory_needs(unsigned long physmem) { return 0; }
#endif
#endif