xref: /linux/arch/s390/include/asm/pgalloc.h (revision d198b34f3855eee2571dda03eea75a09c7c31480)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  S390 version
4  *    Copyright IBM Corp. 1999, 2000
5  *    Author(s): Hartmut Penner (hp@de.ibm.com)
6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
7  *
8  *  Derived from "include/asm-i386/pgalloc.h"
9  *    Copyright (C) 1994  Linus Torvalds
10  */
11 
12 #ifndef _S390_PGALLOC_H
13 #define _S390_PGALLOC_H
14 
15 #include <linux/threads.h>
16 #include <linux/string.h>
17 #include <linux/gfp.h>
18 #include <linux/mm.h>
19 
20 #define CRST_ALLOC_ORDER 2
21 
22 unsigned long *crst_table_alloc(struct mm_struct *);
23 void crst_table_free(struct mm_struct *, unsigned long *);
24 
25 unsigned long *page_table_alloc(struct mm_struct *);
26 struct page *page_table_alloc_pgste(struct mm_struct *mm);
27 void page_table_free(struct mm_struct *, unsigned long *);
28 void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
29 void page_table_free_pgste(struct page *page);
30 extern int page_table_allocate_pgste;
31 
32 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
33 {
34 	memset64((u64 *)crst, entry, _CRST_ENTRIES);
35 }
36 
37 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
38 {
39 	if (mm_pmd_folded(mm))
40 		return _SEGMENT_ENTRY_EMPTY;
41 	if (mm_pud_folded(mm))
42 		return _REGION3_ENTRY_EMPTY;
43 	if (mm_p4d_folded(mm))
44 		return _REGION2_ENTRY_EMPTY;
45 	return _REGION1_ENTRY_EMPTY;
46 }
47 
48 int crst_table_upgrade(struct mm_struct *mm, unsigned long limit);
49 void crst_table_downgrade(struct mm_struct *);
50 
51 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long address)
52 {
53 	unsigned long *table = crst_table_alloc(mm);
54 
55 	if (table)
56 		crst_table_init(table, _REGION2_ENTRY_EMPTY);
57 	return (p4d_t *) table;
58 }
59 
60 static inline void p4d_free(struct mm_struct *mm, p4d_t *p4d)
61 {
62 	if (!mm_p4d_folded(mm))
63 		crst_table_free(mm, (unsigned long *) p4d);
64 }
65 
66 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
67 {
68 	unsigned long *table = crst_table_alloc(mm);
69 	if (table)
70 		crst_table_init(table, _REGION3_ENTRY_EMPTY);
71 	return (pud_t *) table;
72 }
73 
74 static inline void pud_free(struct mm_struct *mm, pud_t *pud)
75 {
76 	if (!mm_pud_folded(mm))
77 		crst_table_free(mm, (unsigned long *) pud);
78 }
79 
80 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
81 {
82 	unsigned long *table = crst_table_alloc(mm);
83 
84 	if (!table)
85 		return NULL;
86 	crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
87 	if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
88 		crst_table_free(mm, table);
89 		return NULL;
90 	}
91 	return (pmd_t *) table;
92 }
93 
94 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
95 {
96 	if (mm_pmd_folded(mm))
97 		return;
98 	pgtable_pmd_page_dtor(virt_to_page(pmd));
99 	crst_table_free(mm, (unsigned long *) pmd);
100 }
101 
102 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
103 {
104 	pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d);
105 }
106 
107 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
108 {
109 	p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud);
110 }
111 
112 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
113 {
114 	pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
115 }
116 
117 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
118 {
119 	unsigned long *table = crst_table_alloc(mm);
120 
121 	if (!table)
122 		return NULL;
123 	if (mm->context.asce_limit == _REGION3_SIZE) {
124 		/* Forking a compat process with 2 page table levels */
125 		if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
126 			crst_table_free(mm, table);
127 			return NULL;
128 		}
129 	}
130 	return (pgd_t *) table;
131 }
132 
133 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
134 {
135 	if (mm->context.asce_limit == _REGION3_SIZE)
136 		pgtable_pmd_page_dtor(virt_to_page(pgd));
137 	crst_table_free(mm, (unsigned long *) pgd);
138 }
139 
140 static inline void pmd_populate(struct mm_struct *mm,
141 				pmd_t *pmd, pgtable_t pte)
142 {
143 	pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
144 }
145 
146 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
147 
148 #define pmd_pgtable(pmd) \
149 	(pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
150 
151 /*
152  * page table entry allocation/free routines.
153  */
154 #define pte_alloc_one_kernel(mm) ((pte_t *)page_table_alloc(mm))
155 #define pte_alloc_one(mm) ((pte_t *)page_table_alloc(mm))
156 
157 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
158 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
159 
160 extern void rcu_table_freelist_finish(void);
161 
162 void vmem_map_init(void);
163 void *vmem_crst_alloc(unsigned long val);
164 pte_t *vmem_pte_alloc(void);
165 
166 unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages);
167 void base_asce_free(unsigned long asce);
168 
169 #endif /* _S390_PGALLOC_H */
170