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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _PGTABLE_NOP4D_H3#define _PGTABLE_NOP4D_H4 5#ifndef __ASSEMBLY__6 7#define __PAGETABLE_P4D_FOLDED 18 9typedef struct { pgd_t pgd; } p4d_t;10 11#define P4D_SHIFT PGDIR_SHIFT12#define PTRS_PER_P4D 113#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-level18 * setup: the p4d is never bad, and a p4d always exists (as it's folded19 * into the pgd entry)20 */21static inline int pgd_none(pgd_t pgd) { return 0; }22static inline int pgd_bad(pgd_t pgd) { return 0; }23static inline int pgd_present(pgd_t pgd) { return 1; }24static 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 35static 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 is48 * inside the pgd, so has no extra memory associated with it.49 */50#define p4d_alloc_one(mm, address) NULL51#define p4d_free(mm, x) do { } while (0)52#define p4d_free_tlb(tlb, x, a) do { } while (0)53 54#undef p4d_addr_end55#define p4d_addr_end(addr, end) (end)56 57#endif /* __ASSEMBLY__ */58#endif /* _PGTABLE_NOP4D_H */59