1/*
2 *  linux/include/asm-arm/pgalloc.h
3 *
4 *  Copyright (C) 2000-2001 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10#ifndef _ASMARM_PGALLOC_H
11#define _ASMARM_PGALLOC_H
12
13#include <asm/domain.h>
14#include <asm/pgtable-hwdef.h>
15#include <asm/processor.h>
16#include <asm/cacheflush.h>
17#include <asm/tlbflush.h>
18
19#define check_pgt_cache()		do { } while (0)
20
21#ifdef CONFIG_MMU
22
23#define _PAGE_USER_TABLE	(PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_USER))
24#define _PAGE_KERNEL_TABLE	(PMD_TYPE_TABLE | PMD_BIT4 | PMD_DOMAIN(DOMAIN_KERNEL))
25
26/*
27 * Since we have only two-level page tables, these are trivial
28 */
29#define pmd_alloc_one(mm,addr)		({ BUG(); ((pmd_t *)2); })
30#define pmd_free(pmd)			do { } while (0)
31#define pgd_populate(mm,pmd,pte)	BUG()
32
33extern pgd_t *get_pgd_slow(struct mm_struct *mm);
34extern void free_pgd_slow(pgd_t *pgd);
35
36#define pgd_alloc(mm)			get_pgd_slow(mm)
37#define pgd_free(pgd)			free_pgd_slow(pgd)
38
39/*
40 * Allocate one PTE table.
41 *
42 * This actually allocates two hardware PTE tables, but we wrap this up
43 * into one table thus:
44 *
45 *  +------------+
46 *  |  h/w pt 0  |
47 *  +------------+
48 *  |  h/w pt 1  |
49 *  +------------+
50 *  | Linux pt 0 |
51 *  +------------+
52 *  | Linux pt 1 |
53 *  +------------+
54 */
55static inline pte_t *
56pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr)
57{
58	pte_t *pte;
59
60	pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
61	if (pte) {
62		clean_dcache_area(pte, sizeof(pte_t) * PTRS_PER_PTE);
63		pte += PTRS_PER_PTE;
64	}
65
66	return pte;
67}
68
69static inline struct page *
70pte_alloc_one(struct mm_struct *mm, unsigned long addr)
71{
72	struct page *pte;
73
74	pte = alloc_pages(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO, 0);
75	if (pte) {
76		void *page = page_address(pte);
77		clean_dcache_area(page, sizeof(pte_t) * PTRS_PER_PTE);
78	}
79
80	return pte;
81}
82
83/*
84 * Free one PTE table.
85 */
86static inline void pte_free_kernel(pte_t *pte)
87{
88	if (pte) {
89		pte -= PTRS_PER_PTE;
90		free_page((unsigned long)pte);
91	}
92}
93
94static inline void pte_free(struct page *pte)
95{
96	__free_page(pte);
97}
98
99static inline void __pmd_populate(pmd_t *pmdp, unsigned long pmdval)
100{
101	pmdp[0] = __pmd(pmdval);
102	pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
103	flush_pmd_entry(pmdp);
104}
105
106/*
107 * Populate the pmdp entry with a pointer to the pte.  This pmd is part
108 * of the mm address space.
109 *
110 * Ensure that we always set both PMD entries.
111 */
112static inline void
113pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmdp, pte_t *ptep)
114{
115	unsigned long pte_ptr = (unsigned long)ptep;
116
117	/*
118	 * The pmd must be loaded with the physical
119	 * address of the PTE table
120	 */
121	pte_ptr -= PTRS_PER_PTE * sizeof(void *);
122	__pmd_populate(pmdp, __pa(pte_ptr) | _PAGE_KERNEL_TABLE);
123}
124
125static inline void
126pmd_populate(struct mm_struct *mm, pmd_t *pmdp, struct page *ptep)
127{
128	__pmd_populate(pmdp, page_to_pfn(ptep) << PAGE_SHIFT | _PAGE_USER_TABLE);
129}
130
131#endif /* CONFIG_MMU */
132
133#endif
134