1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
|
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* vineetg: June 2011
* -"/proc/meminfo | grep PageTables" kept on increasing
* Recently added pgtable dtor was not getting called.
*
* vineetg: May 2011
* -Variable pg-sz means that Page Tables could be variable sized themselves
* So calculate it based on addr traversal split [pgd-bits:pte-bits:xxx]
* -Page Table size capped to max 1 to save memory - hence verified.
* -Since these deal with constants, gcc compile-time optimizes them.
*
* vineetg: Nov 2010
* -Added pgtable ctor/dtor used for pgtable mem accounting
*
* vineetg: April 2010
* -Switched pgtable_t from being struct page * to unsigned long
* =Needed so that Page Table allocator (pte_alloc_one) is not forced to
* deal with struct page. That way in future we can make it allocate
* multiple PG Tbls in one Page Frame
* =sweet side effect is avoiding calls to ugly page_address( ) from the
* pg-tlb allocator sub-sys (pte_alloc_one, ptr_free, pmd_populate)
*
* Amit Bhor, Sameer Dhavale: Codito Technologies 2004
*/
#ifndef _ASM_ARC_PGALLOC_H
#define _ASM_ARC_PGALLOC_H
#include <linux/mm.h>
#include <linux/log2.h>
static inline void
pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
{
pmd_set(pmd, pte);
}
static inline void
pmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t ptep)
{
pmd_set(pmd, (pte_t *) ptep);
}
static inline int __get_order_pgd(void)
{
return get_order(PTRS_PER_PGD * sizeof(pgd_t));
}
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
int num, num2;
pgd_t *ret = (pgd_t *) __get_free_pages(GFP_KERNEL, __get_order_pgd());
if (ret) {
num = USER_PTRS_PER_PGD + USER_KERNEL_GUTTER / PGDIR_SIZE;
memzero(ret, num * sizeof(pgd_t));
num2 = VMALLOC_SIZE / PGDIR_SIZE;
memcpy(ret + num, swapper_pg_dir + num, num2 * sizeof(pgd_t));
memzero(ret + num + num2,
(PTRS_PER_PGD - num - num2) * sizeof(pgd_t));
}
return ret;
}
static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
free_pages((unsigned long)pgd, __get_order_pgd());
}
/*
* With software-only page-tables, addr-split for traversal is tweakable and
* that directly governs how big tables would be at each level.
* Further, the MMU page size is configurable.
* Thus we need to programatically assert the size constraint
* All of this is const math, allowing gcc to do constant folding/propagation.
*/
static inline int __get_order_pte(void)
{
return get_order(PTRS_PER_PTE * sizeof(pte_t));
}
static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
{
pte_t *pte;
pte = (pte_t *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
__get_order_pte());
return pte;
}
static inline pgtable_t
pte_alloc_one(struct mm_struct *mm)
{
pgtable_t pte_pg;
struct page *page;
pte_pg = (pgtable_t)__get_free_pages(GFP_KERNEL, __get_order_pte());
if (!pte_pg)
return 0;
memzero((void *)pte_pg, PTRS_PER_PTE * sizeof(pte_t));
page = virt_to_page(pte_pg);
if (!pgtable_pte_page_ctor(page)) {
__free_page(page);
return 0;
}
return pte_pg;
}
static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
{
free_pages((unsigned long)pte, __get_order_pte()); /* takes phy addr */
}
static inline void pte_free(struct mm_struct *mm, pgtable_t ptep)
{
pgtable_pte_page_dtor(virt_to_page(ptep));
free_pages((unsigned long)ptep, __get_order_pte());
}
#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte)
#endif /* _ASM_ARC_PGALLOC_H */
|
