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/* 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) & 0xff000000),
"Bug: fault blocked by AP register !");
}
#endif /* !__ASSEMBLY__ */
#endif /* CONFIG_PPC_KUAP */
#endif /* _ASM_POWERPC_KUP_8XX_H_ */
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