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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/*
2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation, version 2.
7 *
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
11 * NON INFRINGEMENT. See the GNU General Public License for
12 * more details.
13 *
14 */
15
16#ifndef _ASM_TILE_PGTABLE_32_H
17#define _ASM_TILE_PGTABLE_32_H
18
19/*
20 * The level-1 index is defined by the huge page size. A PGD is composed
21 * of PTRS_PER_PGD pgd_t's and is the top level of the page table.
22 */
23#define PGDIR_SHIFT HV_LOG2_PAGE_SIZE_LARGE
24#define PGDIR_SIZE HV_PAGE_SIZE_LARGE
25#define PGDIR_MASK (~(PGDIR_SIZE-1))
26#define PTRS_PER_PGD (1 << (32 - PGDIR_SHIFT))
27
28/*
29 * The level-2 index is defined by the difference between the huge
30 * page size and the normal page size. A PTE is composed of
31 * PTRS_PER_PTE pte_t's and is the bottom level of the page table.
32 * Note that the hypervisor docs use PTE for what we call pte_t, so
33 * this nomenclature is somewhat confusing.
34 */
35#define PTRS_PER_PTE (1 << (HV_LOG2_PAGE_SIZE_LARGE - HV_LOG2_PAGE_SIZE_SMALL))
36
37#ifndef __ASSEMBLY__
38
39/*
40 * Right now we initialize only a single pte table. It can be extended
41 * easily, subsequent pte tables have to be allocated in one physical
42 * chunk of RAM.
43 *
44 * HOWEVER, if we are using an allocation scheme with slop after the
45 * end of the page table (e.g. where our L2 page tables are 2KB but
46 * our pages are 64KB and we are allocating via the page allocator)
47 * we can't extend it easily.
48 */
49#define LAST_PKMAP PTRS_PER_PTE
50
51#define PKMAP_BASE ((FIXADDR_BOOT_START - PAGE_SIZE*LAST_PKMAP) & PGDIR_MASK)
52
53#ifdef CONFIG_HIGHMEM
54# define __VMAPPING_END (PKMAP_BASE & ~(HPAGE_SIZE-1))
55#else
56# define __VMAPPING_END (FIXADDR_START & ~(HPAGE_SIZE-1))
57#endif
58
59#ifdef CONFIG_HUGEVMAP
60#define HUGE_VMAP_END __VMAPPING_END
61#define HUGE_VMAP_BASE (HUGE_VMAP_END - CONFIG_NR_HUGE_VMAPS * HPAGE_SIZE)
62#define _VMALLOC_END HUGE_VMAP_BASE
63#else
64#define _VMALLOC_END __VMAPPING_END
65#endif
66
67/*
68 * Align the vmalloc area to an L2 page table, and leave a guard page
69 * at the beginning and end. The vmalloc code also puts in an internal
70 * guard page between each allocation.
71 */
72#define VMALLOC_END (_VMALLOC_END - PAGE_SIZE)
73extern unsigned long VMALLOC_RESERVE /* = CONFIG_VMALLOC_RESERVE */;
74#define _VMALLOC_START (_VMALLOC_END - VMALLOC_RESERVE)
75#define VMALLOC_START (_VMALLOC_START + PAGE_SIZE)
76
77/* This is the maximum possible amount of lowmem. */
78#define MAXMEM (_VMALLOC_START - PAGE_OFFSET)
79
80/* We have no pmd or pud since we are strictly a two-level page table */
81#include <asm-generic/pgtable-nopmd.h>
82
83/* We don't define any pgds for these addresses. */
84static inline int pgd_addr_invalid(unsigned long addr)
85{
86 return addr >= MEM_HV_INTRPT;
87}
88
89/*
90 * Provide versions of these routines that can be used safely when
91 * the hypervisor may be asynchronously modifying dirty/accessed bits.
92 * ptep_get_and_clear() matches the generic one but we provide it to
93 * be parallel with the 64-bit code.
94 */
95#define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
96#define __HAVE_ARCH_PTEP_SET_WRPROTECT
97#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
98
99extern int ptep_test_and_clear_young(struct vm_area_struct *,
100 unsigned long addr, pte_t *);
101extern void ptep_set_wrprotect(struct mm_struct *,
102 unsigned long addr, pte_t *);
103
104#define __HAVE_ARCH_PTEP_GET_AND_CLEAR
105static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
106 unsigned long addr, pte_t *ptep)
107{
108 pte_t pte = *ptep;
109 pte_clear(_mm, addr, ptep);
110 return pte;
111}
112
113/* Create a pmd from a PTFN. */
114static inline pmd_t ptfn_pmd(unsigned long ptfn, pgprot_t prot)
115{
116 return (pmd_t){ { hv_pte_set_ptfn(prot, ptfn) } };
117}
118
119/* Return the page-table frame number (ptfn) that a pmd_t points at. */
120#define pmd_ptfn(pmd) hv_pte_get_ptfn((pmd).pud.pgd)
121
122static inline void pmd_clear(pmd_t *pmdp)
123{
124 __pte_clear(&pmdp->pud.pgd);
125}
126
127#endif /* __ASSEMBLY__ */
128
129#endif /* _ASM_TILE_PGTABLE_32_H */