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 #define SIZEOF_PGD (PTRS_PER_PGD * sizeof(pgd_t))
28
29 /*
30 * The level-2 index is defined by the difference between the huge
31 * page size and the normal page size. A PTE is composed of
32 * PTRS_PER_PTE pte_t's and is the bottom level of the page table.
33 * Note that the hypervisor docs use PTE for what we call pte_t, so
34 * this nomenclature is somewhat confusing.
35 */
36 #define PTRS_PER_PTE (1 << (HV_LOG2_PAGE_SIZE_LARGE - HV_LOG2_PAGE_SIZE_SMALL))
37 #define SIZEOF_PTE (PTRS_PER_PTE * sizeof(pte_t))
38
39 #ifndef __ASSEMBLY__
40
41 /*
42 * Right now we initialize only a single pte table. It can be extended
43 * easily, subsequent pte tables have to be allocated in one physical
44 * chunk of RAM.
45 *
46 * HOWEVER, if we are using an allocation scheme with slop after the
47 * end of the page table (e.g. where our L2 page tables are 2KB but
48 * our pages are 64KB and we are allocating via the page allocator)
49 * we can't extend it easily.
50 */
51 #define LAST_PKMAP PTRS_PER_PTE
52
53 #define PKMAP_BASE ((FIXADDR_BOOT_START - PAGE_SIZE*LAST_PKMAP) & PGDIR_MASK)
54
55 #ifdef CONFIG_HIGHMEM
56 # define __VMAPPING_END (PKMAP_BASE & ~(HPAGE_SIZE-1))
57 #else
58 # define __VMAPPING_END (FIXADDR_START & ~(HPAGE_SIZE-1))
59 #endif
60
61 #ifdef CONFIG_HUGEVMAP
62 #define HUGE_VMAP_END __VMAPPING_END
63 #define HUGE_VMAP_BASE (HUGE_VMAP_END - CONFIG_NR_HUGE_VMAPS * HPAGE_SIZE)
64 #define _VMALLOC_END HUGE_VMAP_BASE
65 #else
66 #define _VMALLOC_END __VMAPPING_END
67 #endif
68
69 /*
70 * Align the vmalloc area to an L2 page table, and leave a guard page
71 * at the beginning and end. The vmalloc code also puts in an internal
72 * guard page between each allocation.
73 */
74 #define VMALLOC_END (_VMALLOC_END - PAGE_SIZE)
75 extern unsigned long VMALLOC_RESERVE /* = CONFIG_VMALLOC_RESERVE */;
76 #define _VMALLOC_START (_VMALLOC_END - VMALLOC_RESERVE)
77 #define VMALLOC_START (_VMALLOC_START + PAGE_SIZE)
78
79 /* This is the maximum possible amount of lowmem. */
80 #define MAXMEM (_VMALLOC_START - PAGE_OFFSET)
81
82 /* We have no pmd or pud since we are strictly a two-level page table */
83 #include <asm-generic/pgtable-nopmd.h>
84
85 /* We don't define any pgds for these addresses. */
pgd_addr_invalid(unsigned long addr)86 static inline int pgd_addr_invalid(unsigned long addr)
87 {
88 return addr >= MEM_HV_INTRPT;
89 }
90
91 /*
92 * Provide versions of these routines that can be used safely when
93 * the hypervisor may be asynchronously modifying dirty/accessed bits.
94 * ptep_get_and_clear() matches the generic one but we provide it to
95 * be parallel with the 64-bit code.
96 */
97 #define __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG
98 #define __HAVE_ARCH_PTEP_SET_WRPROTECT
99
100 extern int ptep_test_and_clear_young(struct vm_area_struct *,
101 unsigned long addr, pte_t *);
102 extern void ptep_set_wrprotect(struct mm_struct *,
103 unsigned long addr, pte_t *);
104
105 #define __HAVE_ARCH_PTEP_GET_AND_CLEAR
ptep_get_and_clear(struct mm_struct * mm,unsigned long addr,pte_t * ptep)106 static inline pte_t ptep_get_and_clear(struct mm_struct *mm,
107 unsigned long addr, pte_t *ptep)
108 {
109 pte_t pte = *ptep;
110 pte_clear(_mm, addr, ptep);
111 return pte;
112 }
113
__set_pmd(pmd_t * pmdp,pmd_t pmdval)114 static inline void __set_pmd(pmd_t *pmdp, pmd_t pmdval)
115 {
116 set_pte(&pmdp->pud.pgd, pmdval.pud.pgd);
117 }
118
119 /* Create a pmd from a PTFN. */
ptfn_pmd(unsigned long ptfn,pgprot_t prot)120 static inline pmd_t ptfn_pmd(unsigned long ptfn, pgprot_t prot)
121 {
122 return (pmd_t){ { hv_pte_set_ptfn(prot, ptfn) } };
123 }
124
125 /* Return the page-table frame number (ptfn) that a pmd_t points at. */
126 #define pmd_ptfn(pmd) hv_pte_get_ptfn((pmd).pud.pgd)
127
pmd_clear(pmd_t * pmdp)128 static inline void pmd_clear(pmd_t *pmdp)
129 {
130 __pte_clear(&pmdp->pud.pgd);
131 }
132
133 #endif /* __ASSEMBLY__ */
134
135 #endif /* _ASM_TILE_PGTABLE_32_H */
136