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
18unsigned long *crst_table_alloc(struct mm_struct *);
19void crst_table_free(struct mm_struct *, unsigned long *);
20
21unsigned long *page_table_alloc(struct mm_struct *);
22void page_table_free(struct mm_struct *, unsigned long *);
23void page_table_free_rcu(struct mmu_gather *, unsigned long *, unsigned long);
24extern int page_table_allocate_pgste;
25
26int set_guest_storage_key(struct mm_struct *mm, unsigned long addr,
27			  unsigned long key, bool nq);
28unsigned long get_guest_storage_key(struct mm_struct *mm, unsigned long addr);
29
30static inline void clear_table(unsigned long *s, unsigned long val, size_t n)
31{
32	typedef struct { char _[n]; } addrtype;
33
34	*s = val;
35	n = (n / 256) - 1;
36	asm volatile(
37		"	mvc	8(248,%0),0(%0)\n"
38		"0:	mvc	256(256,%0),0(%0)\n"
39		"	la	%0,256(%0)\n"
40		"	brct	%1,0b\n"
41		: "+a" (s), "+d" (n), "=m" (*(addrtype *) s)
42		: "m" (*(addrtype *) s));
43}
44
45static inline void crst_table_init(unsigned long *crst, unsigned long entry)
46{
47	clear_table(crst, entry, sizeof(unsigned long)*2048);
48}
49
50static inline unsigned long pgd_entry_type(struct mm_struct *mm)
51{
52	if (mm->context.asce_limit <= (1UL << 31))
53		return _SEGMENT_ENTRY_EMPTY;
54	if (mm->context.asce_limit <= (1UL << 42))
55		return _REGION3_ENTRY_EMPTY;
56	return _REGION2_ENTRY_EMPTY;
57}
58
59int crst_table_upgrade(struct mm_struct *, unsigned long limit);
60void crst_table_downgrade(struct mm_struct *, unsigned long limit);
61
62static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long address)
63{
64	unsigned long *table = crst_table_alloc(mm);
65	if (table)
66		crst_table_init(table, _REGION3_ENTRY_EMPTY);
67	return (pud_t *) table;
68}
69#define pud_free(mm, pud) crst_table_free(mm, (unsigned long *) pud)
70
71static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long vmaddr)
72{
73	unsigned long *table = crst_table_alloc(mm);
74
75	if (!table)
76		return NULL;
77	crst_table_init(table, _SEGMENT_ENTRY_EMPTY);
78	if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
79		crst_table_free(mm, table);
80		return NULL;
81	}
82	return (pmd_t *) table;
83}
84
85static inline void pmd_free(struct mm_struct *mm, pmd_t *pmd)
86{
87	pgtable_pmd_page_dtor(virt_to_page(pmd));
88	crst_table_free(mm, (unsigned long *) pmd);
89}
90
91static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, pud_t *pud)
92{
93	pgd_val(*pgd) = _REGION2_ENTRY | __pa(pud);
94}
95
96static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
97{
98	pud_val(*pud) = _REGION3_ENTRY | __pa(pmd);
99}
100
101static inline pgd_t *pgd_alloc(struct mm_struct *mm)
102{
103	unsigned long *table = crst_table_alloc(mm);
104
105	if (!table)
106		return NULL;
107	if (mm->context.asce_limit == (1UL << 31)) {
108		/* Forking a compat process with 2 page table levels */
109		if (!pgtable_pmd_page_ctor(virt_to_page(table))) {
110			crst_table_free(mm, table);
111			return NULL;
112		}
113	}
114	return (pgd_t *) table;
115}
116
117static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
118{
119	if (mm->context.asce_limit == (1UL << 31))
120		pgtable_pmd_page_dtor(virt_to_page(pgd));
121	crst_table_free(mm, (unsigned long *) pgd);
122}
123
124static inline void pmd_populate(struct mm_struct *mm,
125				pmd_t *pmd, pgtable_t pte)
126{
127	pmd_val(*pmd) = _SEGMENT_ENTRY + __pa(pte);
128}
129
130#define pmd_populate_kernel(mm, pmd, pte) pmd_populate(mm, pmd, pte)
131
132#define pmd_pgtable(pmd) \
133	(pgtable_t)(pmd_val(pmd) & -sizeof(pte_t)*PTRS_PER_PTE)
134
135/*
136 * page table entry allocation/free routines.
137 */
138#define pte_alloc_one_kernel(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
139#define pte_alloc_one(mm, vmaddr) ((pte_t *) page_table_alloc(mm))
140
141#define pte_free_kernel(mm, pte) page_table_free(mm, (unsigned long *) pte)
142#define pte_free(mm, pte) page_table_free(mm, (unsigned long *) pte)
143
144extern void rcu_table_freelist_finish(void);
145
146#endif /* _S390_PGALLOC_H */
147