54 lines
1.1 KiB
C
54 lines
1.1 KiB
C
/* 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 */
|