linux/arch/x86/include/asm/pgtable-invert.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_PGTABLE_INVERT_H
#define _ASM_PGTABLE_INVERT_H …

#ifndef __ASSEMBLY__

/*
 * A clear pte value is special, and doesn't get inverted.
 *
 * Note that even users that only pass a pgprot_t (rather
 * than a full pte) won't trigger the special zero case,
 * because even PAGE_NONE has _PAGE_PROTNONE | _PAGE_ACCESSED
 * set. So the all zero case really is limited to just the
 * cleared page table entry case.
 */
static inline bool __pte_needs_invert(u64 val)
{ … }

/* Get a mask to xor with the page table entry to get the correct pfn. */
static inline u64 protnone_mask(u64 val)
{ … }

static inline u64 flip_protnone_guard(u64 oldval, u64 val, u64 mask)
{ … }

#endif /* __ASSEMBLY__ */

#endif