1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * OpenRISC Linux 4 * 5 * Linux architectural port borrowing liberally from similar works of 6 * others. All original copyrights apply as per the original source 7 * declaration. 8 * 9 * OpenRISC implementation: 10 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com> 11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> 12 * et al. 13 */ 14 15 #ifndef __ASM_OPENRISC_PGALLOC_H 16 #define __ASM_OPENRISC_PGALLOC_H 17 18 #include <asm/page.h> 19 #include <linux/threads.h> 20 #include <linux/mm.h> 21 #include <linux/memblock.h> 22 23 extern int mem_init_done; 24 25 #define pmd_populate_kernel(mm, pmd, pte) \ 26 set_pmd(pmd, __pmd(_KERNPG_TABLE + __pa(pte))) 27 28 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, 29 struct page *pte) 30 { 31 set_pmd(pmd, __pmd(_KERNPG_TABLE + 32 ((unsigned long)page_to_pfn(pte) << 33 (unsigned long) PAGE_SHIFT))); 34 } 35 36 /* 37 * Allocate and free page tables. 38 */ 39 static inline pgd_t *pgd_alloc(struct mm_struct *mm) 40 { 41 pgd_t *ret = (pgd_t *)__get_free_page(GFP_KERNEL); 42 43 if (ret) { 44 memset(ret, 0, USER_PTRS_PER_PGD * sizeof(pgd_t)); 45 memcpy(ret + USER_PTRS_PER_PGD, 46 swapper_pg_dir + USER_PTRS_PER_PGD, 47 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t)); 48 49 } 50 return ret; 51 } 52 53 #if 0 54 /* FIXME: This seems to be the preferred style, but we are using 55 * current_pgd (from mm->pgd) to load kernel pages so we need it 56 * initialized. This needs to be looked into. 57 */ 58 extern inline pgd_t *pgd_alloc(struct mm_struct *mm) 59 { 60 return (pgd_t *)get_zeroed_page(GFP_KERNEL); 61 } 62 #endif 63 64 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd) 65 { 66 free_page((unsigned long)pgd); 67 } 68 69 extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm); 70 71 static inline struct page *pte_alloc_one(struct mm_struct *mm) 72 { 73 struct page *pte; 74 pte = alloc_pages(GFP_KERNEL, 0); 75 if (!pte) 76 return NULL; 77 clear_page(page_address(pte)); 78 if (!pgtable_page_ctor(pte)) { 79 __free_page(pte); 80 return NULL; 81 } 82 return pte; 83 } 84 85 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte) 86 { 87 free_page((unsigned long)pte); 88 } 89 90 static inline void pte_free(struct mm_struct *mm, struct page *pte) 91 { 92 pgtable_page_dtor(pte); 93 __free_page(pte); 94 } 95 96 #define __pte_free_tlb(tlb, pte, addr) \ 97 do { \ 98 pgtable_page_dtor(pte); \ 99 tlb_remove_page((tlb), (pte)); \ 100 } while (0) 101 102 #define pmd_pgtable(pmd) pmd_page(pmd) 103 104 #define check_pgt_cache() do { } while (0) 105 106 #endif 107