/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef _LINUX_SECRETMEM_H
#define _LINUX_SECRETMEM_H

#ifdef CONFIG_SECRETMEM

extern const struct address_space_operations secretmem_aops;

static inline bool folio_is_secretmem(struct folio *folio)
{
    struct address_space *mapping;

    /*
     * Using folio_mapping() is quite slow because of the actual call
     * instruction.
     * We know that secretmem pages are not compound, so we can
     * save a couple of cycles here.
     */
    if (folio_test_large(folio))
        return false;

    mapping = (struct address_space *)
        ((unsigned long)folio->mapping & ~PAGE_MAPPING_FLAGS);

    if (!mapping || mapping != folio->mapping)
        return false;

    return mapping->a_ops == &secretmem_aops;
}

bool vma_is_secretmem(struct vm_area_struct *vma);
bool secretmem_active(void);

#else

static inline bool vma_is_secretmem(struct vm_area_struct *vma)
{
    return false;
}

static inline bool folio_is_secretmem(struct folio *folio)
{
    return false;
}

static inline bool secretmem_active(void)
{
    return false;
}

#endif /* CONFIG_SECRETMEM */

#endif /* _LINUX_SECRETMEM_H */