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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
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linux
1#ifndef _X86_64_PGALLOC_H
2#define _X86_64_PGALLOC_H
3
4#include <asm/fixmap.h>
5#include <asm/pda.h>
6#include <linux/threads.h>
7#include <linux/mm.h>
8
9#define pmd_populate_kernel(mm, pmd, pte) \
10 set_pmd(pmd, __pmd(_PAGE_TABLE | __pa(pte)))
11#define pud_populate(mm, pud, pmd) \
12 set_pud(pud, __pud(_PAGE_TABLE | __pa(pmd)))
13#define pgd_populate(mm, pgd, pud) \
14 set_pgd(pgd, __pgd(_PAGE_TABLE | __pa(pud)))
15
16static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, struct page *pte)
17{
18 set_pmd(pmd, __pmd(_PAGE_TABLE | (page_to_pfn(pte) << PAGE_SHIFT)));
19}
20
21static inline pmd_t *get_pmd(void)
22{
23 return (pmd_t *)get_zeroed_page(GFP_KERNEL);
24}
25
26static inline void pmd_free(pmd_t *pmd)
27{
28 BUG_ON((unsigned long)pmd & (PAGE_SIZE-1));
29 free_page((unsigned long)pmd);
30}
31
32static inline pmd_t *pmd_alloc_one (struct mm_struct *mm, unsigned long addr)
33{
34 return (pmd_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
35}
36
37static inline pud_t *pud_alloc_one(struct mm_struct *mm, unsigned long addr)
38{
39 return (pud_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
40}
41
42static inline void pud_free (pud_t *pud)
43{
44 BUG_ON((unsigned long)pud & (PAGE_SIZE-1));
45 free_page((unsigned long)pud);
46}
47
48static inline void pgd_list_add(pgd_t *pgd)
49{
50 struct page *page = virt_to_page(pgd);
51
52 spin_lock(&pgd_lock);
53 page->index = (pgoff_t)pgd_list;
54 if (pgd_list)
55 pgd_list->private = (unsigned long)&page->index;
56 pgd_list = page;
57 page->private = (unsigned long)&pgd_list;
58 spin_unlock(&pgd_lock);
59}
60
61static inline void pgd_list_del(pgd_t *pgd)
62{
63 struct page *next, **pprev, *page = virt_to_page(pgd);
64
65 spin_lock(&pgd_lock);
66 next = (struct page *)page->index;
67 pprev = (struct page **)page->private;
68 *pprev = next;
69 if (next)
70 next->private = (unsigned long)pprev;
71 spin_unlock(&pgd_lock);
72}
73
74static inline pgd_t *pgd_alloc(struct mm_struct *mm)
75{
76 unsigned boundary;
77 pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT);
78 if (!pgd)
79 return NULL;
80 pgd_list_add(pgd);
81 /*
82 * Copy kernel pointers in from init.
83 * Could keep a freelist or slab cache of those because the kernel
84 * part never changes.
85 */
86 boundary = pgd_index(__PAGE_OFFSET);
87 memset(pgd, 0, boundary * sizeof(pgd_t));
88 memcpy(pgd + boundary,
89 init_level4_pgt + boundary,
90 (PTRS_PER_PGD - boundary) * sizeof(pgd_t));
91 return pgd;
92}
93
94static inline void pgd_free(pgd_t *pgd)
95{
96 BUG_ON((unsigned long)pgd & (PAGE_SIZE-1));
97 pgd_list_del(pgd);
98 free_page((unsigned long)pgd);
99}
100
101static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
102{
103 return (pte_t *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
104}
105
106static inline struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
107{
108 void *p = (void *)get_zeroed_page(GFP_KERNEL|__GFP_REPEAT);
109 if (!p)
110 return NULL;
111 return virt_to_page(p);
112}
113
114/* Should really implement gc for free page table pages. This could be
115 done with a reference count in struct page. */
116
117static inline void pte_free_kernel(pte_t *pte)
118{
119 BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
120 free_page((unsigned long)pte);
121}
122
123static inline void pte_free(struct page *pte)
124{
125 __free_page(pte);
126}
127
128#define __pte_free_tlb(tlb,pte) tlb_remove_page((tlb),(pte))
129
130#define __pmd_free_tlb(tlb,x) tlb_remove_page((tlb),virt_to_page(x))
131#define __pud_free_tlb(tlb,x) tlb_remove_page((tlb),virt_to_page(x))
132
133#endif /* _X86_64_PGALLOC_H */