1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_POWERPC_KUP_H_
3#define _ASM_POWERPC_KUP_H_
4
5#define KUAP_READ	1
6#define KUAP_WRITE	2
7#define KUAP_READ_WRITE	(KUAP_READ | KUAP_WRITE)
8/*
9 * For prevent_user_access() only.
10 * Use the current saved situation instead of the to/from/size params.
11 * Used on book3s/32
12 */
13#define KUAP_CURRENT_READ	4
14#define KUAP_CURRENT_WRITE	8
15#define KUAP_CURRENT		(KUAP_CURRENT_READ | KUAP_CURRENT_WRITE)
16
17#ifdef CONFIG_PPC_BOOK3S_64
18#include <asm/book3s/64/kup-radix.h>
19#endif
20#ifdef CONFIG_PPC_8xx
21#include <asm/nohash/32/kup-8xx.h>
22#endif
23#ifdef CONFIG_PPC_BOOK3S_32
24#include <asm/book3s/32/kup.h>
25#endif
26
27#ifdef __ASSEMBLY__
28#ifndef CONFIG_PPC_KUAP
29.macro kuap_save_and_lock	sp, thread, gpr1, gpr2, gpr3
30.endm
31
32.macro kuap_restore	sp, current, gpr1, gpr2, gpr3
33.endm
34
35.macro kuap_check	current, gpr
36.endm
37
38.macro kuap_check_amr	gpr1, gpr2
39.endm
40
41#endif
42
43#else /* !__ASSEMBLY__ */
44
45#include <linux/pgtable.h>
46
47void setup_kup(void);
48
49#ifdef CONFIG_PPC_KUEP
50void setup_kuep(bool disabled);
51#else
52static inline void setup_kuep(bool disabled) { }
53#endif /* CONFIG_PPC_KUEP */
54
55#ifdef CONFIG_PPC_KUAP
56void setup_kuap(bool disabled);
57#else
58static inline void setup_kuap(bool disabled) { }
59
60static inline bool
61bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
62{
63	return false;
64}
65
66static inline void kuap_check_amr(void) { }
67
68/*
69 * book3s/64/kup-radix.h defines these functions for the !KUAP case to flush
70 * the L1D cache after user accesses. Only include the empty stubs for other
71 * platforms.
72 */
73#ifndef CONFIG_PPC_BOOK3S_64
74static inline void allow_user_access(void __user *to, const void __user *from,
75				     unsigned long size, unsigned long dir) { }
76static inline void prevent_user_access(void __user *to, const void __user *from,
77				       unsigned long size, unsigned long dir) { }
78static inline unsigned long prevent_user_access_return(void) { return 0UL; }
79static inline void restore_user_access(unsigned long flags) { }
80#endif /* CONFIG_PPC_BOOK3S_64 */
81#endif /* CONFIG_PPC_KUAP */
82
83static inline void allow_read_from_user(const void __user *from, unsigned long size)
84{
85	allow_user_access(NULL, from, size, KUAP_READ);
86}
87
88static inline void allow_write_to_user(void __user *to, unsigned long size)
89{
90	allow_user_access(to, NULL, size, KUAP_WRITE);
91}
92
93static inline void allow_read_write_user(void __user *to, const void __user *from,
94					 unsigned long size)
95{
96	allow_user_access(to, from, size, KUAP_READ_WRITE);
97}
98
99static inline void prevent_read_from_user(const void __user *from, unsigned long size)
100{
101	prevent_user_access(NULL, from, size, KUAP_READ);
102}
103
104static inline void prevent_write_to_user(void __user *to, unsigned long size)
105{
106	prevent_user_access(to, NULL, size, KUAP_WRITE);
107}
108
109static inline void prevent_read_write_user(void __user *to, const void __user *from,
110					   unsigned long size)
111{
112	prevent_user_access(to, from, size, KUAP_READ_WRITE);
113}
114
115static inline void prevent_current_access_user(void)
116{
117	prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT);
118}
119
120static inline void prevent_current_read_from_user(void)
121{
122	prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT_READ);
123}
124
125static inline void prevent_current_write_to_user(void)
126{
127	prevent_user_access(NULL, NULL, ~0UL, KUAP_CURRENT_WRITE);
128}
129
130#endif /* !__ASSEMBLY__ */
131
132#endif /* _ASM_POWERPC_KUAP_H_ */
133