xref: /openbmc/linux/arch/powerpc/include/asm/kasan.h (revision 55b37d9c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __ASM_KASAN_H
3 #define __ASM_KASAN_H
4 
5 #if defined(CONFIG_KASAN) && !defined(CONFIG_CC_HAS_KASAN_MEMINTRINSIC_PREFIX)
6 #define _GLOBAL_KASAN(fn)	_GLOBAL(__##fn)
7 #define _GLOBAL_TOC_KASAN(fn)	_GLOBAL_TOC(__##fn)
8 #define EXPORT_SYMBOL_KASAN(fn)	EXPORT_SYMBOL(__##fn)
9 #else
10 #define _GLOBAL_KASAN(fn)	_GLOBAL(fn)
11 #define _GLOBAL_TOC_KASAN(fn)	_GLOBAL_TOC(fn)
12 #define EXPORT_SYMBOL_KASAN(fn)
13 #endif
14 
15 #ifndef __ASSEMBLY__
16 
17 #include <asm/page.h>
18 #include <linux/sizes.h>
19 
20 #define KASAN_SHADOW_SCALE_SHIFT	3
21 
22 #if defined(CONFIG_MODULES) && defined(CONFIG_PPC32)
23 #define KASAN_KERN_START	ALIGN_DOWN(PAGE_OFFSET - SZ_256M, SZ_256M)
24 #else
25 #define KASAN_KERN_START	PAGE_OFFSET
26 #endif
27 
28 #define KASAN_SHADOW_START	(KASAN_SHADOW_OFFSET + \
29 				 (KASAN_KERN_START >> KASAN_SHADOW_SCALE_SHIFT))
30 
31 #define KASAN_SHADOW_OFFSET	ASM_CONST(CONFIG_KASAN_SHADOW_OFFSET)
32 
33 #ifdef CONFIG_PPC32
34 #define KASAN_SHADOW_END	(-(-KASAN_SHADOW_START >> KASAN_SHADOW_SCALE_SHIFT))
35 #elif defined(CONFIG_PPC_BOOK3S_64)
36 /*
37  * The shadow ends before the highest accessible address
38  * because we don't need a shadow for the shadow. Instead:
39  * c00e000000000000 << 3 + a80e000000000000 = c00fc00000000000
40  */
41 #define KASAN_SHADOW_END 0xc00fc00000000000UL
42 
43 #else
44 
45 /*
46  * The shadow ends before the highest accessible address
47  * because we don't need a shadow for the shadow.
48  * But it doesn't hurt to have a shadow for the shadow,
49  * keep shadow end aligned eases things.
50  */
51 #define KASAN_SHADOW_END 0xc000200000000000UL
52 
53 #endif
54 
55 #ifdef CONFIG_KASAN
56 #ifdef CONFIG_PPC_BOOK3S_64
57 DECLARE_STATIC_KEY_FALSE(powerpc_kasan_enabled_key);
58 
59 static __always_inline bool kasan_arch_is_ready(void)
60 {
61 	if (static_branch_likely(&powerpc_kasan_enabled_key))
62 		return true;
63 	return false;
64 }
65 
66 #define kasan_arch_is_ready kasan_arch_is_ready
67 #endif
68 
69 void kasan_early_init(void);
70 void kasan_mmu_init(void);
71 void kasan_init(void);
72 void kasan_late_init(void);
73 #else
74 static inline void kasan_init(void) { }
75 static inline void kasan_mmu_init(void) { }
76 static inline void kasan_late_init(void) { }
77 #endif
78 
79 void kasan_update_early_region(unsigned long k_start, unsigned long k_end, pte_t pte);
80 int kasan_init_shadow_page_tables(unsigned long k_start, unsigned long k_end);
81 int kasan_init_region(void *start, size_t size);
82 
83 #endif /* __ASSEMBLY */
84 #endif
85