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