diff options
Diffstat (limited to '')
-rw-r--r-- | arch/powerpc/include/asm/nohash/32/kup-8xx.h | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/nohash/32/kup-8xx.h b/arch/powerpc/include/asm/nohash/32/kup-8xx.h new file mode 100644 index 0000000000..46bc5925e5 --- /dev/null +++ b/arch/powerpc/include/asm/nohash/32/kup-8xx.h @@ -0,0 +1,89 @@ +/* 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 + +#ifndef __ASSEMBLY__ + +#include <asm/reg.h> + +static __always_inline void __kuap_save_and_lock(struct pt_regs *regs) +{ + regs->kuap = mfspr(SPRN_MD_AP); + mtspr(SPRN_MD_AP, MD_APG_KUAP); +} +#define __kuap_save_and_lock __kuap_save_and_lock + +static __always_inline void kuap_user_restore(struct pt_regs *regs) +{ +} + +static __always_inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long kuap) +{ + mtspr(SPRN_MD_AP, regs->kuap); +} + +#ifdef CONFIG_PPC_KUAP_DEBUG +static __always_inline unsigned long __kuap_get_and_assert_locked(void) +{ + WARN_ON_ONCE(mfspr(SPRN_MD_AP) >> 16 != MD_APG_KUAP >> 16); + + return 0; +} +#define __kuap_get_and_assert_locked __kuap_get_and_assert_locked +#endif + +static __always_inline void uaccess_begin_8xx(unsigned long val) +{ + asm(ASM_MMU_FTR_IFSET("mtspr %0, %1", "", %2) : : + "i"(SPRN_MD_AP), "r"(val), "i"(MMU_FTR_KUAP) : "memory"); +} + +static __always_inline void uaccess_end_8xx(void) +{ + asm(ASM_MMU_FTR_IFSET("mtspr %0, %1", "", %2) : : + "i"(SPRN_MD_AP), "r"(MD_APG_KUAP), "i"(MMU_FTR_KUAP) : "memory"); +} + +static __always_inline void allow_user_access(void __user *to, const void __user *from, + unsigned long size, unsigned long dir) +{ + uaccess_begin_8xx(MD_APG_INIT); +} + +static __always_inline void prevent_user_access(unsigned long dir) +{ + uaccess_end_8xx(); +} + +static __always_inline unsigned long prevent_user_access_return(void) +{ + unsigned long flags; + + flags = mfspr(SPRN_MD_AP); + + uaccess_end_8xx(); + + return flags; +} + +static __always_inline void restore_user_access(unsigned long flags) +{ + uaccess_begin_8xx(flags); +} + +static __always_inline bool +__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write) +{ + return !((regs->kuap ^ MD_APG_KUAP) & 0xff000000); +} + +#endif /* !__ASSEMBLY__ */ + +#endif /* CONFIG_PPC_KUAP */ + +#endif /* _ASM_POWERPC_KUP_8XX_H_ */ |