xref: /openbmc/linux/arch/s390/include/asm/pgalloc.h (revision 4da722ca)
1 /*
2  *  S390 version
3  *    Copyright IBM Corp. 1999, 2000
4  *    Author(s): Hartmut Penner (hp@de.ibm.com)
5  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
6  *
7  *  Derived from "include/asm-i386/pgalloc.h"
8  *    Copyright (C) 1994  Linus Torvalds
9  */
10 
11 #ifndef _S390_PGALLOC_H
12 #define _S390_PGALLOC_H
13 
14 #include <linux/threads.h>
15 #include <linux/gfp.h>
16 #include <linux/mm.h>
17 
18 unsigned long *crst_table_alloc(struct mm_struct *);
19 void crst_table_free(struct mm_struct *, unsigned long *);
20 
21 unsigned long *page_table_alloc(struct mm_struct *);
22 struct page *page_table_alloc_pgste(struct mm_struct *mm);
23 void page_table_free(struct mm_struct *, unsigned long *);
24 void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
25 void page_table_free_pgste(struct page *page);
26 extern int page_table_allocate_pgste;
27 
28 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
29 {
30 	struct addrtype { char _[256]; };
31 	int i;
32 
33 	for (i = 0; i < n; i += 256) {
34 		*s = val;
35 		asm volatile(
36 			"mvc	8(248,%[s]),0(%[s])\n"
37 			: "+m" (*(struct addrtype *) s)
38 			: [s] "a" (s));
39 		s += 256 / sizeof(long);
40 	}
41 }
42 
43 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
44 {
45 	clear_table(crst, entry, sizeof(unsigned long)*2048);
46 }
47 
48 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
49 {
50 	if (mm->context.asce_limit <= (1UL << 31))
51 		return _SEGMENT_ENTRY_EMPTY;
52 	if (mm->context.asce_limit <= (1UL << 42))
53 		return _REGION3_ENTRY_EMPTY;
54 	if (mm->context.asce_limit <= (1UL << 53))
55 		return _REGION2_ENTRY_EMPTY;
56 	return _REGION1_ENTRY_EMPTY;
57 }
58 
59 int crst_table_upgrade(struct mm_struct *mm, unsigned long limit);
60 void crst_table_downgrade(struct mm_struct *);
61 
62 static inline p4d_t *p4d_alloc_one(struct mm_struct *mm, unsigned long address)
63 {
64 	unsigned long *table = crst_table_alloc(mm);
65 
66 	if (table)
67 		crst_table_init(table, _REGION2_ENTRY_EMPTY);
68 	return (p4d_t *) table;
69 }
70 #define p4d_free(mm, p4d) crst_table_free(mm, (unsigned long *) p4d)
71 
72 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
73 {
74 	unsigned long *table = crst_table_alloc(mm);
75 	if (table)
76 		crst_table_init(table, _REGION3_ENTRY_EMPTY);
77 	return (pud_t *) table;
78 }
79 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
80 
81 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
82 {
83 	unsigned long *table = crst_table_alloc(mm);
84 
85 	if (!table)
86 		return NULL;
87 	crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
88 	if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
89 		crst_table_free(mm, table);
90 		return NULL;
91 	}
92 	return (pmd_t *) table;
93 }
94 
95 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
96 {
97 	pgtable_pmd_page_dtor(virt_to_page(pmd));
98 	crst_table_free(mm, (unsigned long *) pmd);
99 }
100 
101 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
102 {
103 	pgd_val(*pgd) = _REGION1_ENTRY | __pa(p4d);
104 }
105 
106 static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
107 {
108 	p4d_val(*p4d) = _REGION2_ENTRY | __pa(pud);
109 }
110 
111 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
112 {
113 	pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
114 }
115 
116 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
117 {
118 	unsigned long *table = crst_table_alloc(mm);
119 
120 	if (!table)
121 		return NULL;
122 	if (mm->context.asce_limit == (1UL << 31)) {
123 		/* Forking a compat process with 2 page table levels */
124 		if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
125 			crst_table_free(mm, table);
126 			return NULL;
127 		}
128 	}
129 	return (pgd_t *) table;
130 }
131 
132 static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
133 {
134 	if (mm->context.asce_limit == (1UL << 31))
135 		pgtable_pmd_page_dtor(virt_to_page(pgd));
136 	crst_table_free(mm, (unsigned long *) pgd);
137 }
138 
139 static inline void pmd_populate(struct mm_struct *mm,
140 				pmd_t *pmd, pgtable_t pte)
141 {
142 	pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
143 }
144 
145 #define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
146 
147 #define pmd_pgtable(pmd) \
148 	(pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
149 
150 /*
151  * page table entry allocation/free routines.
152  */
153 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
154 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
155 
156 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
157 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
158 
159 extern void rcu_table_freelist_finish(void);
160 
161 #endif /* _S390_PGALLOC_H */
162