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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_POWERPC_KUP_H_
#define _ASM_POWERPC_KUP_H_
#define KUAP_READ 1
#define KUAP_WRITE 2
#define KUAP_READ_WRITE (KUAP_READ | KUAP_WRITE)
#ifndef __ASSEMBLY__
#include <linux/types.h>
static __always_inline bool kuap_is_disabled(void);
#endif
#ifdef CONFIG_PPC_BOOK3S_64
#include <asm/book3s/64/kup.h>
#endif
#ifdef CONFIG_PPC_8xx
#include <asm/nohash/32/kup-8xx.h>
#endif
#ifdef CONFIG_BOOKE_OR_40x
#include <asm/nohash/kup-booke.h>
#endif
#ifdef CONFIG_PPC_BOOK3S_32
#include <asm/book3s/32/kup.h>
#endif
#ifdef __ASSEMBLY__
#ifndef CONFIG_PPC_KUAP
.macro kuap_check_amr gpr1, gpr2
.endm
#endif
#else /* !__ASSEMBLY__ */
extern bool disable_kuep;
extern bool disable_kuap;
#include <linux/pgtable.h>
void setup_kup(void);
void setup_kuep(bool disabled);
#ifdef CONFIG_PPC_KUAP
void setup_kuap(bool disabled);
static __always_inline bool kuap_is_disabled(void)
{
return !mmu_has_feature(MMU_FTR_KUAP);
}
#else
static inline void setup_kuap(bool disabled) { }
static __always_inline bool kuap_is_disabled(void) { return true; }
static __always_inline bool
__bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
{
return false;
}
static __always_inline void kuap_user_restore(struct pt_regs *regs) { }
static __always_inline void __kuap_kernel_restore(struct pt_regs *regs, unsigned long amr) { }
/*
* book3s/64/kup-radix.h defines these functions for the !KUAP case to flush
* the L1D cache after user accesses. Only include the empty stubs for other
* platforms.
*/
#ifndef CONFIG_PPC_BOOK3S_64
static __always_inline void allow_user_access(void __user *to, const void __user *from,
unsigned long size, unsigned long dir) { }
static __always_inline void prevent_user_access(unsigned long dir) { }
static __always_inline unsigned long prevent_user_access_return(void) { return 0UL; }
static __always_inline void restore_user_access(unsigned long flags) { }
#endif /* CONFIG_PPC_BOOK3S_64 */
#endif /* CONFIG_PPC_KUAP */
static __always_inline bool
bad_kuap_fault(struct pt_regs *regs, unsigned long address, bool is_write)
{
if (kuap_is_disabled())
return false;
return __bad_kuap_fault(regs, address, is_write);
}
static __always_inline void kuap_lock(void)
{
#ifdef __kuap_lock
if (kuap_is_disabled())
return;
__kuap_lock();
#endif
}
static __always_inline void kuap_save_and_lock(struct pt_regs *regs)
{
#ifdef __kuap_save_and_lock
if (kuap_is_disabled())
return;
__kuap_save_and_lock(regs);
#endif
}
static __always_inline void kuap_kernel_restore(struct pt_regs *regs, unsigned long amr)
{
if (kuap_is_disabled())
return;
__kuap_kernel_restore(regs, amr);
}
static __always_inline unsigned long kuap_get_and_assert_locked(void)
{
#ifdef __kuap_get_and_assert_locked
if (!kuap_is_disabled())
return __kuap_get_and_assert_locked();
#endif
return 0;
}
static __always_inline void kuap_assert_locked(void)
{
if (IS_ENABLED(CONFIG_PPC_KUAP_DEBUG))
kuap_get_and_assert_locked();
}
static __always_inline void allow_read_from_user(const void __user *from, unsigned long size)
{
barrier_nospec();
allow_user_access(NULL, from, size, KUAP_READ);
}
static __always_inline void allow_write_to_user(void __user *to, unsigned long size)
{
allow_user_access(to, NULL, size, KUAP_WRITE);
}
static __always_inline void allow_read_write_user(void __user *to, const void __user *from,
unsigned long size)
{
barrier_nospec();
allow_user_access(to, from, size, KUAP_READ_WRITE);
}
static __always_inline void prevent_read_from_user(const void __user *from, unsigned long size)
{
prevent_user_access(KUAP_READ);
}
static __always_inline void prevent_write_to_user(void __user *to, unsigned long size)
{
prevent_user_access(KUAP_WRITE);
}
static __always_inline void prevent_read_write_user(void __user *to, const void __user *from,
unsigned long size)
{
prevent_user_access(KUAP_READ_WRITE);
}
static __always_inline void prevent_current_access_user(void)
{
prevent_user_access(KUAP_READ_WRITE);
}
static __always_inline void prevent_current_read_from_user(void)
{
prevent_user_access(KUAP_READ);
}
static __always_inline void prevent_current_write_to_user(void)
{
prevent_user_access(KUAP_WRITE);
}
#endif /* !__ASSEMBLY__ */
#endif /* _ASM_POWERPC_KUAP_H_ */
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