xref: /openbmc/linux/arch/s390/include/asm/pgalloc.h (revision 83a530e1)
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->context.asce_limit <= _REGION3_SIZE)
40 		return _SEGMENT_ENTRY_EMPTY;
41 	if (mm->context.asce_limit <= _REGION2_SIZE)
42 		return _REGION3_ENTRY_EMPTY;
43 	if (mm->context.asce_limit <= _REGION1_SIZE)
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 #define p4d_free(mm, p4d) crst_table_free(mm, (unsigned long *) p4d)
60 
61 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
62 {
63 	unsigned long *table = crst_table_alloc(mm);
64 	if (table)
65 		crst_table_init(table, _REGION3_ENTRY_EMPTY);
66 	return (pud_t *) table;
67 }
68 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
69 
70 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
71 {
72 	unsigned long *table = crst_table_alloc(mm);
73 
74 	if (!table)
75 		return NULL;
76 	crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
77 	if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
78 		crst_table_free(mm, table);
79 		return NULL;
80 	}
81 	return (pmd_t *) table;
82 }
83 
84 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
85 {
86 	pgtable_pmd_page_dtor(virt_to_page(pmd));
87 	crst_table_free(mm, (unsigned long *) pmd);
88 }
89 
90 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
91 {
92 	pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d);
93 }
94 
95 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
96 {
97 	p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud);
98 }
99 
100 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
101 {
102 	pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
103 }
104 
105 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
106 {
107 	unsigned long *table = crst_table_alloc(mm);
108 
109 	if (!table)
110 		return NULL;
111 	if (mm->context.asce_limit == _REGION3_SIZE) {
112 		/* Forking a compat process with 2 page table levels */
113 		if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
114 			crst_table_free(mm, table);
115 			return NULL;
116 		}
117 	}
118 	return (pgd_t *) table;
119 }
120 
121 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
122 {
123 	if (mm->context.asce_limit == _REGION3_SIZE)
124 		pgtable_pmd_page_dtor(virt_to_page(pgd));
125 	crst_table_free(mm, (unsigned long *) pgd);
126 }
127 
128 static inline void pmd_populate(struct mm_struct *mm,
129 				pmd_t *pmd, pgtable_t pte)
130 {
131 	pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
132 }
133 
134 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
135 
136 #define pmd_pgtable(pmd) \
137 	(pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
138 
139 /*
140  * page table entry allocation/free routines.
141  */
142 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
143 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
144 
145 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
146 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
147 
148 extern void rcu_table_freelist_finish(void);
149 
150 void vmem_map_init(void);
151 void *vmem_crst_alloc(unsigned long val);
152 pte_t *vmem_pte_alloc(void);
153 
154 unsigned long base_asce_alloc(unsigned long addr, unsigned long num_pages);
155 void base_asce_free(unsigned long asce);
156 
157 #endif /* _S390_PGALLOC_H */
158