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Linux kernel mirror (for testing)
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kernel
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linux
1#ifndef _PGTABLE_NOP4D_H
2#define _PGTABLE_NOP4D_H
3
4#ifndef __ASSEMBLY__
5
6#define __PAGETABLE_P4D_FOLDED
7
8typedef struct { pgd_t pgd; } p4d_t;
9
10#define P4D_SHIFT PGDIR_SHIFT
11#define PTRS_PER_P4D 1
12#define P4D_SIZE (1UL << P4D_SHIFT)
13#define P4D_MASK (~(P4D_SIZE-1))
14
15/*
16 * The "pgd_xxx()" functions here are trivial for a folded two-level
17 * setup: the p4d is never bad, and a p4d always exists (as it's folded
18 * into the pgd entry)
19 */
20static inline int pgd_none(pgd_t pgd) { return 0; }
21static inline int pgd_bad(pgd_t pgd) { return 0; }
22static inline int pgd_present(pgd_t pgd) { return 1; }
23static inline void pgd_clear(pgd_t *pgd) { }
24#define p4d_ERROR(p4d) (pgd_ERROR((p4d).pgd))
25
26#define pgd_populate(mm, pgd, p4d) do { } while (0)
27/*
28 * (p4ds are folded into pgds so this doesn't get actually called,
29 * but the define is needed for a generic inline function.)
30 */
31#define set_pgd(pgdptr, pgdval) set_p4d((p4d_t *)(pgdptr), (p4d_t) { pgdval })
32
33static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address)
34{
35 return (p4d_t *)pgd;
36}
37
38#define p4d_val(x) (pgd_val((x).pgd))
39#define __p4d(x) ((p4d_t) { __pgd(x) })
40
41#define pgd_page(pgd) (p4d_page((p4d_t){ pgd }))
42#define pgd_page_vaddr(pgd) (p4d_page_vaddr((p4d_t){ pgd }))
43
44/*
45 * allocating and freeing a p4d is trivial: the 1-entry p4d is
46 * inside the pgd, so has no extra memory associated with it.
47 */
48#define p4d_alloc_one(mm, address) NULL
49#define p4d_free(mm, x) do { } while (0)
50#define __p4d_free_tlb(tlb, x, a) do { } while (0)
51
52#undef p4d_addr_end
53#define p4d_addr_end(addr, end) (end)
54
55#endif /* __ASSEMBLY__ */
56#endif /* _PGTABLE_NOP4D_H */