1 /*
2  *  include/asm-s390/pgalloc.h
3  *
4  *  S390 version
5  *    Copyright (C) 1999,2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
6  *    Author(s): Hartmut Penner (hp@de.ibm.com)
7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
8  *
9  *  Derived from "include/asm-i386/pgalloc.h"
10  *    Copyright (C) 1994  Linus Torvalds
11  */
12 
13 #ifndef _S390_PGALLOC_H
14 #define _S390_PGALLOC_H
15 
16 #include <linux/threads.h>
17 #include <linux/gfp.h>
18 #include <linux/mm.h>
19 
20 #define check_pgt_cache()	do {} while (0)
21 
22 unsigned long *crst_table_alloc(struct mm_struct *, int);
23 void crst_table_free(struct mm_struct *, unsigned long *);
24 void crst_table_free_rcu(struct mm_struct *, unsigned long *);
25 
26 unsigned long *page_table_alloc(struct mm_struct *);
27 void page_table_free(struct mm_struct *, unsigned long *);
28 void page_table_free_rcu(struct mm_struct *, unsigned long *);
29 void disable_noexec(struct mm_struct *, struct task_struct *);
30 
clear_table(unsigned long * s,unsigned long val,size_t n)31 static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
32 {
33 	typedef struct { char _[n]; } addrtype;
34 
35 	*s = val;
36 	n = (n / 256) - 1;
37 	asm volatile(
38 #ifdef CONFIG_64BIT
39 		"	mvc	8(248,%0),0(%0)\n"
40 #else
41 		"	mvc	4(252,%0),0(%0)\n"
42 #endif
43 		"0:	mvc	256(256,%0),0(%0)\n"
44 		"	la	%0,256(%0)\n"
45 		"	brct	%1,0b\n"
46 		: "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
47 		: "m" (*(addrtype *) s));
48 }
49 
crst_table_init(unsigned long * crst,unsigned long entry)50 static inline void crst_table_init(unsigned long *crst, unsigned long entry)
51 {
52 	clear_table(crst, entry, sizeof(unsigned long)*2048);
53 	crst = get_shadow_table(crst);
54 	if (crst)
55 		clear_table(crst, entry, sizeof(unsigned long)*2048);
56 }
57 
58 #ifndef __s390x__
59 
pgd_entry_type(struct mm_struct * mm)60 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
61 {
62 	return _SEGMENT_ENTRY_EMPTY;
63 }
64 
65 #define pud_alloc_one(mm,address)		({ BUG(); ((pud_t *)2); })
66 #define pud_free(mm, x)				do { } while (0)
67 
68 #define pmd_alloc_one(mm,address)		({ BUG(); ((pmd_t *)2); })
69 #define pmd_free(mm, x)				do { } while (0)
70 
71 #define pgd_populate(mm, pgd, pud)		BUG()
72 #define pgd_populate_kernel(mm, pgd, pud)	BUG()
73 
74 #define pud_populate(mm, pud, pmd)		BUG()
75 #define pud_populate_kernel(mm, pud, pmd)	BUG()
76 
77 #else /* __s390x__ */
78 
pgd_entry_type(struct mm_struct * mm)79 static inline unsigned long pgd_entry_type(struct mm_struct *mm)
80 {
81 	if (mm->context.asce_limit <= (1UL << 31))
82 		return _SEGMENT_ENTRY_EMPTY;
83 	if (mm->context.asce_limit <= (1UL << 42))
84 		return _REGION3_ENTRY_EMPTY;
85 	return _REGION2_ENTRY_EMPTY;
86 }
87 
88 int crst_table_upgrade(struct mm_struct *, unsigned long limit);
89 void crst_table_downgrade(struct mm_struct *, unsigned long limit);
90 
pud_alloc_one(struct mm_struct * mm,unsigned long address)91 static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
92 {
93 	unsigned long *table = crst_table_alloc(mm, mm->context.noexec);
94 	if (table)
95 		crst_table_init(table, _REGION3_ENTRY_EMPTY);
96 	return (pud_t *) table;
97 }
98 #define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
99 
pmd_alloc_one(struct mm_struct * mm,unsigned long vmaddr)100 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
101 {
102 	unsigned long *table = crst_table_alloc(mm, mm->context.noexec);
103 	if (table)
104 		crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
105 	return (pmd_t *) table;
106 }
107 #define pmd_free(mm, pmd) crst_table_free(mm, (unsigned long *) pmd)
108 
pgd_populate_kernel(struct mm_struct * mm,pgd_t * pgd,pud_t * pud)109 static inline void pgd_populate_kernel(struct mm_struct *mm,
110 				       pgd_t *pgd, pud_t *pud)
111 {
112 	pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
113 }
114 
pgd_populate(struct mm_struct * mm,pgd_t * pgd,pud_t * pud)115 static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
116 {
117 	pgd_populate_kernel(mm, pgd, pud);
118 	if (mm->context.noexec) {
119 		pgd = get_shadow_table(pgd);
120 		pud = get_shadow_table(pud);
121 		pgd_populate_kernel(mm, pgd, pud);
122 	}
123 }
124 
pud_populate_kernel(struct mm_struct * mm,pud_t * pud,pmd_t * pmd)125 static inline void pud_populate_kernel(struct mm_struct *mm,
126 				       pud_t *pud, pmd_t *pmd)
127 {
128 	pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
129 }
130 
pud_populate(struct mm_struct * mm,pud_t * pud,pmd_t * pmd)131 static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
132 {
133 	pud_populate_kernel(mm, pud, pmd);
134 	if (mm->context.noexec) {
135 		pud = get_shadow_table(pud);
136 		pmd = get_shadow_table(pmd);
137 		pud_populate_kernel(mm, pud, pmd);
138 	}
139 }
140 
141 #endif /* __s390x__ */
142 
pgd_alloc(struct mm_struct * mm)143 static inline pgd_t *pgd_alloc(struct mm_struct *mm)
144 {
145 	spin_lock_init(&mm->context.list_lock);
146 	INIT_LIST_HEAD(&mm->context.crst_list);
147 	INIT_LIST_HEAD(&mm->context.pgtable_list);
148 	return (pgd_t *)
149 		crst_table_alloc(mm, user_mode == SECONDARY_SPACE_MODE);
150 }
151 #define pgd_free(mm, pgd) crst_table_free(mm, (unsigned long *) pgd)
152 
pmd_populate_kernel(struct mm_struct * mm,pmd_t * pmd,pte_t * pte)153 static inline void pmd_populate_kernel(struct mm_struct *mm,
154 				       pmd_t *pmd, pte_t *pte)
155 {
156 	pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
157 }
158 
pmd_populate(struct mm_struct * mm,pmd_t * pmd,pgtable_t pte)159 static inline void pmd_populate(struct mm_struct *mm,
160 				pmd_t *pmd, pgtable_t pte)
161 {
162 	pmd_populate_kernel(mm, pmd, pte);
163 	if (mm->context.noexec) {
164 		pmd = get_shadow_table(pmd);
165 		pmd_populate_kernel(mm, pmd, pte + PTRS_PER_PTE);
166 	}
167 }
168 
169 #define pmd_pgtable(pmd) \
170 	(pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
171 
172 /*
173  * page table entry allocation/free routines.
174  */
175 #define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
176 #define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
177 
178 #define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
179 #define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
180 
181 extern void rcu_table_freelist_finish(void);
182 
183 #endif /* _S390_PGALLOC_H */
184