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 */
32 extern 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
43 extern unsigned long *zero_cache; /* head linked list of pre-zero'd pages */
44 extern atomic_t zero_sz; /* # currently pre-zero'd pages */
45 extern atomic_t zeropage_hits; /* # zero'd pages request that we've done */
46 extern atomic_t zeropage_calls; /* # zero'd pages request that've been made */
47 extern 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 */
59 extern unsigned long get_zero_page_fast(void);
60
61 extern void __bad_pte(pmd_t *pmd);
62
get_pgd_slow(void)63 extern 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
get_pgd_fast(void)73 extern 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
free_pgd_fast(pgd_t * pgd)87 extern 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
free_pgd_slow(pgd_t * pgd)94 extern 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
111 extern pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long addr);
112
pte_alloc_one(struct mm_struct * mm,unsigned long address)113 static inline struct page *pte_alloc_one(struct mm_struct *mm,
114 unsigned long address)
115 {
116 struct page *ptepage;
117
118 #ifdef CONFIG_HIGHPTE
119 int flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_REPEAT;
120 #else
121 int flags = GFP_KERNEL | __GFP_REPEAT;
122 #endif
123
124 ptepage = alloc_pages(flags, 0);
125 if (ptepage)
126 clear_highpage(ptepage);
127 return ptepage;
128 }
129
pte_alloc_one_fast(struct mm_struct * mm,unsigned long address)130 static inline pte_t *pte_alloc_one_fast(struct mm_struct *mm,
131 unsigned long address)
132 {
133 unsigned long *ret;
134
135 ret = pte_quicklist;
136 if (ret != NULL) {
137 pte_quicklist = (unsigned long *)(*ret);
138 ret[0] = 0;
139 pgtable_cache_size--;
140 }
141 return (pte_t *)ret;
142 }
143
pte_free_fast(pte_t * pte)144 extern inline void pte_free_fast(pte_t *pte)
145 {
146 *(unsigned long **)pte = pte_quicklist;
147 pte_quicklist = (unsigned long *) pte;
148 pgtable_cache_size++;
149 }
150
pte_free_kernel(struct mm_struct * mm,pte_t * pte)151 extern inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
152 {
153 free_page((unsigned long)pte);
154 }
155
pte_free_slow(struct page * ptepage)156 extern inline void pte_free_slow(struct page *ptepage)
157 {
158 __free_page(ptepage);
159 }
160
pte_free(struct mm_struct * mm,struct page * ptepage)161 extern inline void pte_free(struct mm_struct *mm, struct page *ptepage)
162 {
163 __free_page(ptepage);
164 }
165
166 #define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, (pte))
167
168 #define pmd_populate(mm, pmd, pte) \
169 (pmd_val(*(pmd)) = (unsigned long)page_address(pte))
170
171 #define pmd_populate_kernel(mm, pmd, pte) \
172 (pmd_val(*(pmd)) = (unsigned long) (pte))
173
174 /*
175 * We don't have any real pmd's, and this code never triggers because
176 * the pgd will always be present..
177 */
178 #define pmd_alloc_one(mm, address) ({ BUG(); ((pmd_t *)2); })
179 #define pmd_free(mm, x) do { } while (0)
180 #define __pmd_free_tlb(tlb, x, addr) pmd_free((tlb)->mm, x)
181 #define pgd_populate(mm, pmd, pte) BUG()
182
183 extern int do_check_pgt_cache(int, int);
184
185 #endif /* CONFIG_MMU */
186
187 #define check_pgt_cache() do { } while (0)
188
189 #endif /* _ASM_MICROBLAZE_PGALLOC_H */
190