| /* SPDX-License-Identifier: GPL-2.0 */ |
| #ifndef _ASM_POWERPC_KUP_8XX_H_ |
| #define _ASM_POWERPC_KUP_8XX_H_ |
| |
| #include <asm/bug.h> |
| #include <asm/mmu.h> |
| |
| #ifdef CONFIG_PPC_KUAP |
| |
| #ifdef __ASSEMBLY__ |
| |
| .macro kuap_save_and_lock sp, thread, gpr1, gpr2, gpr3 |
| lis \gpr2, MD_APG_KUAP@h /* only APG0 and APG1 are used */ |
| mfspr \gpr1, SPRN_MD_AP |
| mtspr SPRN_MD_AP, \gpr2 |
| stw \gpr1, STACK_REGS_KUAP(\sp) |
| .endm |
| |
| .macro kuap_restore sp, current, gpr1, gpr2, gpr3 |
| lwz \gpr1, STACK_REGS_KUAP(\sp) |
| mtspr SPRN_MD_AP, \gpr1 |
| .endm |
| |
| .macro kuap_check current, gpr |
| #ifdef CONFIG_PPC_KUAP_DEBUG |
| mfspr \gpr, SPRN_MD_AP |
| rlwinm \gpr, \gpr, 16, 0xffff |
| 999: twnei \gpr, MD_APG_KUAP@h |
| EMIT_BUG_ENTRY 999b, __FILE__, __LINE__, (BUGFLAG_WARNING | BUGFLAG_ONCE) |
| #endif |
| .endm |
| |
| #else /* !__ASSEMBLY__ */ |
| |
| #include <asm/reg.h> |
| |
| static inline void allow_user_access(void __user *to, const void __user *from, |
| unsigned long size, unsigned long dir) |
| { |
| mtspr(SPRN_MD_AP, MD_APG_INIT); |
| } |
| |
| static inline void prevent_user_access(void __user *to, const void __user *from, |
| unsigned long size, unsigned long dir) |
| { |
| mtspr(SPRN_MD_AP, MD_APG_KUAP); |
| } |
| |
| static inline unsigned long prevent_user_access_return(void) |
| { |
| unsigned long flags = mfspr(SPRN_MD_AP); |
| |
| mtspr(SPRN_MD_AP, MD_APG_KUAP); |
| |
| return flags; |
| } |
| |
| static inline void restore_user_access(unsigned long flags) |
| { |
| mtspr(SPRN_MD_AP, flags); |
| } |
| |
| static inline bool |
| bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) |
| { |
| return WARN(!((regs->kuap ^ MD_APG_KUAP) & 0xf0000000), |
| "Bug: fault blocked by AP register !"); |
| } |
| |
| #endif /* !__ASSEMBLY__ */ |
| |
| #endif /* CONFIG_PPC_KUAP */ |
| |
| #endif /* _ASM_POWERPC_KUP_8XX_H_ */ |
