1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _PGTABLE_NOPUD_H
3 #define _PGTABLE_NOPUD_H
4
5 #ifndef __ASSEMBLY__
6
7 #ifdef __ARCH_USE_5LEVEL_HACK
8 #include <asm-generic/pgtable-nop4d-hack.h>
9 #else
10 #include <asm-generic/pgtable-nop4d.h>
11
12 #define __PAGETABLE_PUD_FOLDED 1
13
14 /*
15 * Having the pud type consist of a p4d gets the size right, and allows
16 * us to conceptually access the p4d entry that this pud is folded into
17 * without casting.
18 */
19 typedef struct { p4d_t p4d; } pud_t;
20
21 #define PUD_SHIFT P4D_SHIFT
22 #define PTRS_PER_PUD 1
23 #define PUD_SIZE (1UL << PUD_SHIFT)
24 #define PUD_MASK (~(PUD_SIZE-1))
25
26 /*
27 * The "p4d_xxx()" functions here are trivial for a folded two-level
28 * setup: the pud is never bad, and a pud always exists (as it's folded
29 * into the p4d entry)
30 */
p4d_none(p4d_t p4d)31 static inline int p4d_none(p4d_t p4d) { return 0; }
p4d_bad(p4d_t p4d)32 static inline int p4d_bad(p4d_t p4d) { return 0; }
p4d_present(p4d_t p4d)33 static inline int p4d_present(p4d_t p4d) { return 1; }
p4d_clear(p4d_t * p4d)34 static inline void p4d_clear(p4d_t *p4d) { }
35 #define pud_ERROR(pud) (p4d_ERROR((pud).p4d))
36
37 #define p4d_populate(mm, p4d, pud) do { } while (0)
38 /*
39 * (puds are folded into p4ds so this doesn't get actually called,
40 * but the define is needed for a generic inline function.)
41 */
42 #define set_p4d(p4dptr, p4dval) set_pud((pud_t *)(p4dptr), (pud_t) { p4dval })
43
pud_offset(p4d_t * p4d,unsigned long address)44 static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
45 {
46 return (pud_t *)p4d;
47 }
48
49 #define pud_val(x) (p4d_val((x).p4d))
50 #define __pud(x) ((pud_t) { __p4d(x) })
51
52 #define p4d_page(p4d) (pud_page((pud_t){ p4d }))
53 #define p4d_page_vaddr(p4d) (pud_page_vaddr((pud_t){ p4d }))
54
55 /*
56 * allocating and freeing a pud is trivial: the 1-entry pud is
57 * inside the p4d, so has no extra memory associated with it.
58 */
59 #define pud_alloc_one(mm, address) NULL
60 #define pud_free(mm, x) do { } while (0)
61 #define __pud_free_tlb(tlb, x, a) do { } while (0)
62
63 #undef pud_addr_end
64 #define pud_addr_end(addr, end) (end)
65
66 #endif /* __ASSEMBLY__ */
67 #endif /* !__ARCH_USE_5LEVEL_HACK */
68 #endif /* _PGTABLE_NOPUD_H */
69