diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/frv/mm/pgalloc.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/frv/mm/pgalloc.c')
-rw-r--r-- | arch/frv/mm/pgalloc.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/arch/frv/mm/pgalloc.c b/arch/frv/mm/pgalloc.c new file mode 100644 index 000000000000..4eaec0f3525b --- /dev/null +++ b/arch/frv/mm/pgalloc.c | |||
@@ -0,0 +1,159 @@ | |||
1 | /* pgalloc.c: page directory & page table allocation | ||
2 | * | ||
3 | * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. | ||
4 | * Written by David Howells (dhowells@redhat.com) | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or | ||
7 | * modify it under the terms of the GNU General Public License | ||
8 | * as published by the Free Software Foundation; either version | ||
9 | * 2 of the License, or (at your option) any later version. | ||
10 | */ | ||
11 | |||
12 | #include <linux/sched.h> | ||
13 | #include <linux/slab.h> | ||
14 | #include <linux/mm.h> | ||
15 | #include <linux/highmem.h> | ||
16 | #include <asm/pgalloc.h> | ||
17 | #include <asm/page.h> | ||
18 | #include <asm/cacheflush.h> | ||
19 | |||
20 | pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((aligned(PAGE_SIZE))); | ||
21 | kmem_cache_t *pgd_cache; | ||
22 | |||
23 | pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) | ||
24 | { | ||
25 | pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT); | ||
26 | if (pte) | ||
27 | clear_page(pte); | ||
28 | return pte; | ||
29 | } | ||
30 | |||
31 | struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address) | ||
32 | { | ||
33 | struct page *page; | ||
34 | |||
35 | #ifdef CONFIG_HIGHPTE | ||
36 | page = alloc_pages(GFP_KERNEL|__GFP_HIGHMEM|__GFP_REPEAT, 0); | ||
37 | #else | ||
38 | page = alloc_pages(GFP_KERNEL|__GFP_REPEAT, 0); | ||
39 | #endif | ||
40 | if (page) | ||
41 | clear_highpage(page); | ||
42 | flush_dcache_page(page); | ||
43 | return page; | ||
44 | } | ||
45 | |||
46 | void __set_pmd(pmd_t *pmdptr, unsigned long pmd) | ||
47 | { | ||
48 | unsigned long *__ste_p = pmdptr->ste; | ||
49 | int loop; | ||
50 | |||
51 | if (!pmd) { | ||
52 | memset(__ste_p, 0, PME_SIZE); | ||
53 | } | ||
54 | else { | ||
55 | BUG_ON(pmd & (0x3f00 | xAMPRx_SS | 0xe)); | ||
56 | |||
57 | for (loop = PME_SIZE; loop > 0; loop -= 4) { | ||
58 | *__ste_p++ = pmd; | ||
59 | pmd += __frv_PT_SIZE; | ||
60 | } | ||
61 | } | ||
62 | |||
63 | frv_dcache_writeback((unsigned long) pmdptr, (unsigned long) (pmdptr + 1)); | ||
64 | } | ||
65 | |||
66 | /* | ||
67 | * List of all pgd's needed for non-PAE so it can invalidate entries | ||
68 | * in both cached and uncached pgd's; not needed for PAE since the | ||
69 | * kernel pmd is shared. If PAE were not to share the pmd a similar | ||
70 | * tactic would be needed. This is essentially codepath-based locking | ||
71 | * against pageattr.c; it is the unique case in which a valid change | ||
72 | * of kernel pagetables can't be lazily synchronized by vmalloc faults. | ||
73 | * vmalloc faults work because attached pagetables are never freed. | ||
74 | * If the locking proves to be non-performant, a ticketing scheme with | ||
75 | * checks at dup_mmap(), exec(), and other mmlist addition points | ||
76 | * could be used. The locking scheme was chosen on the basis of | ||
77 | * manfred's recommendations and having no core impact whatsoever. | ||
78 | * -- wli | ||
79 | */ | ||
80 | DEFINE_SPINLOCK(pgd_lock); | ||
81 | struct page *pgd_list; | ||
82 | |||
83 | static inline void pgd_list_add(pgd_t *pgd) | ||
84 | { | ||
85 | struct page *page = virt_to_page(pgd); | ||
86 | page->index = (unsigned long) pgd_list; | ||
87 | if (pgd_list) | ||
88 | pgd_list->private = (unsigned long) &page->index; | ||
89 | pgd_list = page; | ||
90 | page->private = (unsigned long) &pgd_list; | ||
91 | } | ||
92 | |||
93 | static inline void pgd_list_del(pgd_t *pgd) | ||
94 | { | ||
95 | struct page *next, **pprev, *page = virt_to_page(pgd); | ||
96 | next = (struct page *) page->index; | ||
97 | pprev = (struct page **) page->private; | ||
98 | *pprev = next; | ||
99 | if (next) | ||
100 | next->private = (unsigned long) pprev; | ||
101 | } | ||
102 | |||
103 | void pgd_ctor(void *pgd, kmem_cache_t *cache, unsigned long unused) | ||
104 | { | ||
105 | unsigned long flags; | ||
106 | |||
107 | if (PTRS_PER_PMD == 1) | ||
108 | spin_lock_irqsave(&pgd_lock, flags); | ||
109 | |||
110 | memcpy((pgd_t *) pgd + USER_PGDS_IN_LAST_PML4, | ||
111 | swapper_pg_dir + USER_PGDS_IN_LAST_PML4, | ||
112 | (PTRS_PER_PGD - USER_PGDS_IN_LAST_PML4) * sizeof(pgd_t)); | ||
113 | |||
114 | if (PTRS_PER_PMD > 1) | ||
115 | return; | ||
116 | |||
117 | pgd_list_add(pgd); | ||
118 | spin_unlock_irqrestore(&pgd_lock, flags); | ||
119 | memset(pgd, 0, USER_PGDS_IN_LAST_PML4 * sizeof(pgd_t)); | ||
120 | } | ||
121 | |||
122 | /* never called when PTRS_PER_PMD > 1 */ | ||
123 | void pgd_dtor(void *pgd, kmem_cache_t *cache, unsigned long unused) | ||
124 | { | ||
125 | unsigned long flags; /* can be called from interrupt context */ | ||
126 | |||
127 | spin_lock_irqsave(&pgd_lock, flags); | ||
128 | pgd_list_del(pgd); | ||
129 | spin_unlock_irqrestore(&pgd_lock, flags); | ||
130 | } | ||
131 | |||
132 | pgd_t *pgd_alloc(struct mm_struct *mm) | ||
133 | { | ||
134 | pgd_t *pgd; | ||
135 | |||
136 | pgd = kmem_cache_alloc(pgd_cache, GFP_KERNEL); | ||
137 | if (!pgd) | ||
138 | return pgd; | ||
139 | |||
140 | return pgd; | ||
141 | } | ||
142 | |||
143 | void pgd_free(pgd_t *pgd) | ||
144 | { | ||
145 | /* in the non-PAE case, clear_page_tables() clears user pgd entries */ | ||
146 | kmem_cache_free(pgd_cache, pgd); | ||
147 | } | ||
148 | |||
149 | void __init pgtable_cache_init(void) | ||
150 | { | ||
151 | pgd_cache = kmem_cache_create("pgd", | ||
152 | PTRS_PER_PGD * sizeof(pgd_t), | ||
153 | PTRS_PER_PGD * sizeof(pgd_t), | ||
154 | 0, | ||
155 | pgd_ctor, | ||
156 | pgd_dtor); | ||
157 | if (!pgd_cache) | ||
158 | panic("pgtable_cache_init(): Cannot create pgd cache"); | ||
159 | } | ||