1*4882a593Smuzhiyun /* SPDX-License-Identifier: GPL-2.0 */
2*4882a593Smuzhiyun #ifndef _ASM_POWERPC_KUP_8XX_H_
3*4882a593Smuzhiyun #define _ASM_POWERPC_KUP_8XX_H_
4*4882a593Smuzhiyun
5*4882a593Smuzhiyun #include <asm/bug.h>
6*4882a593Smuzhiyun #include <asm/mmu.h>
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #ifdef CONFIG_PPC_KUAP
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun #ifdef __ASSEMBLY__
11*4882a593Smuzhiyun
12*4882a593Smuzhiyun .macro kuap_save_and_lock sp, thread, gpr1, gpr2, gpr3
13*4882a593Smuzhiyun lis \gpr2, MD_APG_KUAP@h /* only APG0 and APG1 are used */
14*4882a593Smuzhiyun mfspr \gpr1, SPRN_MD_AP
15*4882a593Smuzhiyun mtspr SPRN_MD_AP, \gpr2
16*4882a593Smuzhiyun stw \gpr1, STACK_REGS_KUAP(\sp)
17*4882a593Smuzhiyun .endm
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun .macro kuap_restore sp, current, gpr1, gpr2, gpr3
20*4882a593Smuzhiyun lwz \gpr1, STACK_REGS_KUAP(\sp)
21*4882a593Smuzhiyun mtspr SPRN_MD_AP, \gpr1
22*4882a593Smuzhiyun .endm
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun .macro kuap_check current, gpr
25*4882a593Smuzhiyun #ifdef CONFIG_PPC_KUAP_DEBUG
26*4882a593Smuzhiyun mfspr \gpr, SPRN_MD_AP
27*4882a593Smuzhiyun rlwinm \gpr, \gpr, 16, 0xffff
28*4882a593Smuzhiyun 999: twnei \gpr, MD_APG_KUAP@h
29*4882a593Smuzhiyun EMIT_BUG_ENTRY 999b, __FILE__, __LINE__, (BUGFLAG_WARNING | BUGFLAG_ONCE)
30*4882a593Smuzhiyun #endif
31*4882a593Smuzhiyun .endm
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun #else /* !__ASSEMBLY__ */
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun #include <asm/reg.h>
36*4882a593Smuzhiyun
allow_user_access(void __user * to,const void __user * from,unsigned long size,unsigned long dir)37*4882a593Smuzhiyun static inline void allow_user_access(void __user *to, const void __user *from,
38*4882a593Smuzhiyun unsigned long size, unsigned long dir)
39*4882a593Smuzhiyun {
40*4882a593Smuzhiyun mtspr(SPRN_MD_AP, MD_APG_INIT);
41*4882a593Smuzhiyun }
42*4882a593Smuzhiyun
prevent_user_access(void __user * to,const void __user * from,unsigned long size,unsigned long dir)43*4882a593Smuzhiyun static inline void prevent_user_access(void __user *to, const void __user *from,
44*4882a593Smuzhiyun unsigned long size, unsigned long dir)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun mtspr(SPRN_MD_AP, MD_APG_KUAP);
47*4882a593Smuzhiyun }
48*4882a593Smuzhiyun
prevent_user_access_return(void)49*4882a593Smuzhiyun static inline unsigned long prevent_user_access_return(void)
50*4882a593Smuzhiyun {
51*4882a593Smuzhiyun unsigned long flags = mfspr(SPRN_MD_AP);
52*4882a593Smuzhiyun
53*4882a593Smuzhiyun mtspr(SPRN_MD_AP, MD_APG_KUAP);
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun return flags;
56*4882a593Smuzhiyun }
57*4882a593Smuzhiyun
restore_user_access(unsigned long flags)58*4882a593Smuzhiyun static inline void restore_user_access(unsigned long flags)
59*4882a593Smuzhiyun {
60*4882a593Smuzhiyun mtspr(SPRN_MD_AP, flags);
61*4882a593Smuzhiyun }
62*4882a593Smuzhiyun
63*4882a593Smuzhiyun static inline bool
bad_kuap_fault(struct pt_regs * regs,unsigned long address,bool is_write)64*4882a593Smuzhiyun bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
65*4882a593Smuzhiyun {
66*4882a593Smuzhiyun return WARN(!((regs->kuap ^ MD_APG_KUAP) & 0xff000000),
67*4882a593Smuzhiyun "Bug: fault blocked by AP register !");
68*4882a593Smuzhiyun }
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun #endif /* !__ASSEMBLY__ */
71*4882a593Smuzhiyun
72*4882a593Smuzhiyun #endif /* CONFIG_PPC_KUAP */
73*4882a593Smuzhiyun
74*4882a593Smuzhiyun #endif /* _ASM_POWERPC_KUP_8XX_H_ */
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