1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_POWERPC_KUP_8XX_H_
3 #define _ASM_POWERPC_KUP_8XX_H_
4
5 #include <asm/bug.h>
6
7 #ifdef CONFIG_PPC_KUAP
8
9 #ifdef __ASSEMBLY__
10
11 .macro kuap_save_and_lock sp, thread, gpr1, gpr2, gpr3
12 lis \gpr2, MD_APG_KUAP@h /* only APG0 and APG1 are used */
13 mfspr \gpr1, SPRN_MD_AP
14 mtspr SPRN_MD_AP, \gpr2
15 stw \gpr1, STACK_REGS_KUAP(\sp)
16 .endm
17
18 .macro kuap_restore sp, current, gpr1, gpr2, gpr3
19 lwz \gpr1, STACK_REGS_KUAP(\sp)
20 mtspr SPRN_MD_AP, \gpr1
21 .endm
22
23 .macro kuap_check current, gpr
24 #ifdef CONFIG_PPC_KUAP_DEBUG
25 mfspr \gpr, SPRN_MD_AP
26 rlwinm \gpr, \gpr, 16, 0xffff
27 999: twnei \gpr, MD_APG_KUAP@h
28 EMIT_BUG_ENTRY 999b, __FILE__, __LINE__, (BUGFLAG_WARNING | BUGFLAG_ONCE)
29 #endif
30 .endm
31
32 #else /* !__ASSEMBLY__ */
33
34 #include <asm/reg.h>
35
allow_user_access(void __user * to,const void __user * from,unsigned long size)36 static inline void allow_user_access(void __user *to, const void __user *from,
37 unsigned long size)
38 {
39 mtspr(SPRN_MD_AP, MD_APG_INIT);
40 }
41
prevent_user_access(void __user * to,const void __user * from,unsigned long size)42 static inline void prevent_user_access(void __user *to, const void __user *from,
43 unsigned long size)
44 {
45 mtspr(SPRN_MD_AP, MD_APG_KUAP);
46 }
47
bad_kuap_fault(struct pt_regs * regs,bool is_write)48 static inline bool bad_kuap_fault(struct pt_regs *regs, bool is_write)
49 {
50 return WARN(!((regs->kuap ^ MD_APG_KUAP) & 0xf0000000),
51 "Bug: fault blocked by AP register !");
52 }
53
54 #endif /* !__ASSEMBLY__ */
55
56 #endif /* CONFIG_PPC_KUAP */
57
58 #endif /* _ASM_POWERPC_KUP_8XX_H_ */
59