Linux kernel mirror (for testing)
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linux
1/*
2 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
3 * Copyright (C) 2008-2009 PetaLogix
4 * Copyright (C) 2006 Atmark Techno, Inc.
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11#ifndef _ASM_MICROBLAZE_PGALLOC_H
12#define _ASM_MICROBLAZE_PGALLOC_H
13
14#ifdef CONFIG_MMU
15
16#include <linux/kernel.h> /* For min/max macros */
17#include <linux/highmem.h>
18#include <asm/setup.h>
19#include <asm/io.h>
20#include <asm/page.h>
21#include <asm/cache.h>
22#include <asm/pgtable.h>
23
24#define PGDIR_ORDER 0
25
26/*
27 * This is handled very differently on MicroBlaze since out page tables
28 * are all 0's and I want to be able to use these zero'd pages elsewhere
29 * as well - it gives us quite a speedup.
30 * -- Cort
31 */
32extern struct pgtable_cache_struct {
33 unsigned long *pgd_cache;
34 unsigned long *pte_cache;
35 unsigned long pgtable_cache_sz;
36} quicklists;
37
38#define pgd_quicklist (quicklists.pgd_cache)
39#define pmd_quicklist ((unsigned long *)0)
40#define pte_quicklist (quicklists.pte_cache)
41#define pgtable_cache_size (quicklists.pgtable_cache_sz)
42
43extern unsigned long *zero_cache; /* head linked list of pre-zero'd pages */
44extern atomic_t zero_sz; /* # currently pre-zero'd pages */
45extern atomic_t zeropage_hits; /* # zero'd pages request that we've done */
46extern atomic_t zeropage_calls; /* # zero'd pages request that've been made */
47extern atomic_t zerototal; /* # pages zero'd over time */
48
49#define zero_quicklist (zero_cache)
50#define zero_cache_sz (zero_sz)
51#define zero_cache_calls (zeropage_calls)
52#define zero_cache_hits (zeropage_hits)
53#define zero_cache_total (zerototal)
54
55/*
56 * return a pre-zero'd page from the list,
57 * return NULL if none available -- Cort
58 */
59extern unsigned long get_zero_page_fast(void);
60
61extern void __bad_pte(pmd_t *pmd);
62
63static inline pgd_t *get_pgd_slow(void)
64{
65 pgd_t *ret;
66
67 ret = (pgd_t *)__get_free_pages(GFP_KERNEL, PGDIR_ORDER);
68 if (ret != NULL)
69 clear_page(ret);
70 return ret;
71}
72
73static inline pgd_t *get_pgd_fast(void)
74{
75 unsigned long *ret;
76
77 ret = pgd_quicklist;
78 if (ret != NULL) {
79 pgd_quicklist = (unsigned long *)(*ret);
80 ret[0] = 0;
81 pgtable_cache_size--;
82 } else
83 ret = (unsigned long *)get_pgd_slow();
84 return (pgd_t *)ret;
85}
86
87static inline void free_pgd_fast(pgd_t *pgd)
88{
89 *(unsigned long **)pgd = pgd_quicklist;
90 pgd_quicklist = (unsigned long *) pgd;
91 pgtable_cache_size++;
92}
93
94static inline void free_pgd_slow(pgd_t *pgd)
95{
96 free_page((unsigned long)pgd);
97}
98
99#define pgd_free(mm, pgd) free_pgd_fast(pgd)
100#define pgd_alloc(mm) get_pgd_fast()
101
102#define pmd_pgtable(pmd) pmd_page(pmd)
103
104/*
105 * We don't have any real pmd's, and this code never triggers because
106 * the pgd will always be present..
107 */
108#define pmd_alloc_one_fast(mm, address) ({ BUG(); ((pmd_t *)1); })
109#define pmd_alloc_one(mm, address) ({ BUG(); ((pmd_t *)2); })
110
111extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm);
112
113static inline struct page *pte_alloc_one(struct mm_struct *mm)
114{
115 struct page *ptepage;
116
117#ifdef CONFIG_HIGHPTE
118 int flags = GFP_KERNEL | __GFP_HIGHMEM;
119#else
120 int flags = GFP_KERNEL;
121#endif
122
123 ptepage = alloc_pages(flags, 0);
124 if (!ptepage)
125 return NULL;
126 clear_highpage(ptepage);
127 if (!pgtable_page_ctor(ptepage)) {
128 __free_page(ptepage);
129 return NULL;
130 }
131 return ptepage;
132}
133
134static inline void pte_free_fast(pte_t *pte)
135{
136 *(unsigned long **)pte = pte_quicklist;
137 pte_quicklist = (unsigned long *) pte;
138 pgtable_cache_size++;
139}
140
141static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
142{
143 free_page((unsigned long)pte);
144}
145
146static inline void pte_free_slow(struct page *ptepage)
147{
148 __free_page(ptepage);
149}
150
151static inline void pte_free(struct mm_struct *mm, struct page *ptepage)
152{
153 pgtable_page_dtor(ptepage);
154 __free_page(ptepage);
155}
156
157#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, (pte))
158
159#define pmd_populate(mm, pmd, pte) \
160 (pmd_val(*(pmd)) = (unsigned long)page_address(pte))
161
162#define pmd_populate_kernel(mm, pmd, pte) \
163 (pmd_val(*(pmd)) = (unsigned long) (pte))
164
165/*
166 * We don't have any real pmd's, and this code never triggers because
167 * the pgd will always be present..
168 */
169#define pmd_alloc_one(mm, address) ({ BUG(); ((pmd_t *)2); })
170#define pmd_free(mm, x) do { } while (0)
171#define __pmd_free_tlb(tlb, x, addr) pmd_free((tlb)->mm, x)
172#define pgd_populate(mm, pmd, pte) BUG()
173
174extern int do_check_pgt_cache(int, int);
175
176#endif /* CONFIG_MMU */
177
178#define check_pgt_cache() do { } while (0)
179
180#endif /* _ASM_MICROBLAZE_PGALLOC_H */