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 MAX_PTRS_PER_P4D 1 13 #define PTRS_PER_P4D 1 14 #define P4D_SIZE (1UL << P4D_SHIFT) 15 #define P4D_MASK (~(P4D_SIZE-1)) 16 17 /* 18 * The "pgd_xxx()" functions here are trivial for a folded two-level 19 * setup: the p4d is never bad, and a p4d always exists (as it's folded 20 * into the pgd entry) 21 */ 22 static inline int pgd_none(pgd_t pgd) { return 0; } 23 static inline int pgd_bad(pgd_t pgd) { return 0; } 24 static inline int pgd_present(pgd_t pgd) { return 1; } 25 static inline void pgd_clear(pgd_t *pgd) { } 26 #define p4d_ERROR(p4d) (pgd_ERROR((p4d).pgd)) 27 28 #define pgd_populate(mm, pgd, p4d) do { } while (0) 29 #define pgd_populate_safe(mm, pgd, p4d) do { } while (0) 30 /* 31 * (p4ds are folded into pgds so this doesn't get actually called, 32 * but the define is needed for a generic inline function.) 33 */ 34 #define set_pgd(pgdptr, pgdval) set_p4d((p4d_t *)(pgdptr), (p4d_t) { pgdval }) 35 36 static inline p4d_t *p4d_offset(pgd_t *pgd, unsigned long address) 37 { 38 return (p4d_t *)pgd; 39 } 40 41 #define p4d_val(x) (pgd_val((x).pgd)) 42 #define __p4d(x) ((p4d_t) { __pgd(x) }) 43 44 #define pgd_page(pgd) (p4d_page((p4d_t){ pgd })) 45 #define pgd_page_vaddr(pgd) (p4d_page_vaddr((p4d_t){ pgd })) 46 47 /* 48 * allocating and freeing a p4d is trivial: the 1-entry p4d is 49 * inside the pgd, so has no extra memory associated with it. 50 */ 51 #define p4d_alloc_one(mm, address) NULL 52 #define p4d_free(mm, x) do { } while (0) 53 #define __p4d_free_tlb(tlb, x, a) do { } while (0) 54 55 #undef p4d_addr_end 56 #define p4d_addr_end(addr, end) (end) 57 58 #endif /* __ASSEMBLY__ */ 59 #endif /* _PGTABLE_NOP4D_H */ 60