1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _PGTABLE_NOP4D_H |
3 | #define _PGTABLE_NOP4D_H |
4 | |
5 | #ifndef __ASSEMBLY__ |
6 | |
7 | #define __PAGETABLE_P4D_FOLDED 1 |
8 | |
9 | typedef struct { pgd_t pgd; } p4d_t; |
10 | |
11 | #define P4D_SHIFT PGDIR_SHIFT |
12 | #define PTRS_PER_P4D 1 |
13 | #define P4D_SIZE (1UL << P4D_SHIFT) |
14 | #define P4D_MASK (~(P4D_SIZE-1)) |
15 | |
16 | /* |
17 | * The "pgd_xxx()" functions here are trivial for a folded two-level |
18 | * setup: the p4d is never bad, and a p4d always exists (as it's folded |
19 | * into the pgd entry) |
20 | */ |
21 | static inline int pgd_none(pgd_t pgd) { return 0; } |
22 | static inline int pgd_bad(pgd_t pgd) { return 0; } |
23 | static inline int pgd_present(pgd_t pgd) { return 1; } |
24 | static inline void pgd_clear(pgd_t *pgd) { } |
25 | #define p4d_ERROR(p4d) (pgd_ERROR((p4d).pgd)) |
26 | |
27 | #define pgd_populate(mm, pgd, p4d) do { } while (0) |
28 | #define pgd_populate_safe(mm, pgd, p4d) do { } while (0) |
29 | /* |
30 | * (p4ds are folded into pgds so this doesn't get actually called, |
31 | * but the define is needed for a generic inline function.) |
32 | */ |
33 | #define set_pgd(pgdptr, pgdval) set_p4d((p4d_t *)(pgdptr), (p4d_t) { pgdval }) |
34 | |
35 | static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address) |
36 | { |
37 | return (p4d_t *)pgd; |
38 | } |
39 | |
40 | #define p4d_val(x) (pgd_val((x).pgd)) |
41 | #define __p4d(x) ((p4d_t) { __pgd(x) }) |
42 | |
43 | #define pgd_page(pgd) (p4d_page((p4d_t){ pgd })) |
44 | #define pgd_page_vaddr(pgd) ((unsigned long)(p4d_pgtable((p4d_t){ pgd }))) |
45 | |
46 | /* |
47 | * allocating and freeing a p4d is trivial: the 1-entry p4d is |
48 | * inside the pgd, so has no extra memory associated with it. |
49 | */ |
50 | #define p4d_alloc_one(mm, address) NULL |
51 | #define p4d_free(mm, x) do { } while (0) |
52 | #define p4d_free_tlb(tlb, x, a) do { } while (0) |
53 | |
54 | #undef p4d_addr_end |
55 | #define p4d_addr_end(addr, end) (end) |
56 | |
57 | #endif /* __ASSEMBLY__ */ |
58 | #endif /* _PGTABLE_NOP4D_H */ |
59 | |