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 #ifndef _ASM_TILE_PGALLOC_H
16 #define _ASM_TILE_PGALLOC_H
17
18 #include <linux/threads.h>
19 #include <linux/mm.h>
20 #include <linux/mmzone.h>
21 #include <asm/fixmap.h>
22 #include <asm/page.h>
23 #include <hv/hypervisor.h>
24
25 /* Bits for the size of the second-level page table. */
26 #define L2_KERNEL_PGTABLE_SHIFT _HV_LOG2_L2_SIZE(HPAGE_SHIFT, PAGE_SHIFT)
27
28 /* How big is a kernel L2 page table? */
29 #define L2_KERNEL_PGTABLE_SIZE (1UL << L2_KERNEL_PGTABLE_SHIFT)
30
31 /* We currently allocate user L2 page tables by page (unlike kernel L2s). */
32 #if L2_KERNEL_PGTABLE_SHIFT < PAGE_SHIFT
33 #define L2_USER_PGTABLE_SHIFT PAGE_SHIFT
34 #else
35 #define L2_USER_PGTABLE_SHIFT L2_KERNEL_PGTABLE_SHIFT
36 #endif
37
38 /* How many pages do we need, as an "order", for a user L2 page table? */
39 #define L2_USER_PGTABLE_ORDER (L2_USER_PGTABLE_SHIFT - PAGE_SHIFT)
40
set_pmd(pmd_t * pmdp,pmd_t pmd)41 static inline void set_pmd(pmd_t *pmdp, pmd_t pmd)
42 {
43 #ifdef CONFIG_64BIT
44 set_pte(pmdp, pmd);
45 #else
46 set_pte(&pmdp->pud.pgd, pmd.pud.pgd);
47 #endif
48 }
49
pmd_populate_kernel(struct mm_struct * mm,pmd_t * pmd,pte_t * ptep)50 static inline void pmd_populate_kernel(struct mm_struct *mm,
51 pmd_t *pmd, pte_t *ptep)
52 {
53 set_pmd(pmd, ptfn_pmd(HV_CPA_TO_PTFN(__pa(ptep)),
54 __pgprot(_PAGE_PRESENT)));
55 }
56
pmd_populate(struct mm_struct * mm,pmd_t * pmd,pgtable_t page)57 static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
58 pgtable_t page)
59 {
60 set_pmd(pmd, ptfn_pmd(HV_CPA_TO_PTFN(PFN_PHYS(page_to_pfn(page))),
61 __pgprot(_PAGE_PRESENT)));
62 }
63
64 /*
65 * Allocate and free page tables.
66 */
67
68 extern pgd_t *pgd_alloc(struct mm_struct *mm);
69 extern void pgd_free(struct mm_struct *mm, pgd_t *pgd);
70
71 extern pgtable_t pgtable_alloc_one(struct mm_struct *mm, unsigned long address,
72 int order);
73 extern void pgtable_free(struct mm_struct *mm, struct page *pte, int order);
74
pte_alloc_one(struct mm_struct * mm,unsigned long address)75 static inline pgtable_t pte_alloc_one(struct mm_struct *mm,
76 unsigned long address)
77 {
78 return pgtable_alloc_one(mm, address, L2_USER_PGTABLE_ORDER);
79 }
80
pte_free(struct mm_struct * mm,struct page * pte)81 static inline void pte_free(struct mm_struct *mm, struct page *pte)
82 {
83 pgtable_free(mm, pte, L2_USER_PGTABLE_ORDER);
84 }
85
86 #define pmd_pgtable(pmd) pmd_page(pmd)
87
88 static inline pte_t *
pte_alloc_one_kernel(struct mm_struct * mm,unsigned long address)89 pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
90 {
91 return pfn_to_kaddr(page_to_pfn(pte_alloc_one(mm, address)));
92 }
93
pte_free_kernel(struct mm_struct * mm,pte_t * pte)94 static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
95 {
96 BUG_ON((unsigned long)pte & (PAGE_SIZE-1));
97 pte_free(mm, virt_to_page(pte));
98 }
99
100 extern void __pgtable_free_tlb(struct mmu_gather *tlb, struct page *pte,
101 unsigned long address, int order);
__pte_free_tlb(struct mmu_gather * tlb,struct page * pte,unsigned long address)102 static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte,
103 unsigned long address)
104 {
105 __pgtable_free_tlb(tlb, pte, address, L2_USER_PGTABLE_ORDER);
106 }
107
108 #define check_pgt_cache() do { } while (0)
109
110 /*
111 * Get the small-page pte_t lowmem entry for a given pfn.
112 * This may or may not be in use, depending on whether the initial
113 * huge-page entry for the page has already been shattered.
114 */
115 pte_t *get_prealloc_pte(unsigned long pfn);
116
117 /* During init, we can shatter kernel huge pages if needed. */
118 void shatter_pmd(pmd_t *pmd);
119
120 /* After init, a more complex technique is required. */
121 void shatter_huge_page(unsigned long addr);
122
123 #ifdef __tilegx__
124
125 #define pud_populate(mm, pud, pmd) \
126 pmd_populate_kernel((mm), (pmd_t *)(pud), (pte_t *)(pmd))
127
128 /* Bits for the size of the L1 (intermediate) page table. */
129 #define L1_KERNEL_PGTABLE_SHIFT _HV_LOG2_L1_SIZE(HPAGE_SHIFT)
130
131 /* How big is a kernel L2 page table? */
132 #define L1_KERNEL_PGTABLE_SIZE (1UL << L1_KERNEL_PGTABLE_SHIFT)
133
134 /* We currently allocate L1 page tables by page. */
135 #if L1_KERNEL_PGTABLE_SHIFT < PAGE_SHIFT
136 #define L1_USER_PGTABLE_SHIFT PAGE_SHIFT
137 #else
138 #define L1_USER_PGTABLE_SHIFT L1_KERNEL_PGTABLE_SHIFT
139 #endif
140
141 /* How many pages do we need, as an "order", for an L1 page table? */
142 #define L1_USER_PGTABLE_ORDER (L1_USER_PGTABLE_SHIFT - PAGE_SHIFT)
143
pmd_alloc_one(struct mm_struct * mm,unsigned long address)144 static inline pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
145 {
146 struct page *p = pgtable_alloc_one(mm, address, L1_USER_PGTABLE_ORDER);
147 return (pmd_t *)page_to_virt(p);
148 }
149
pmd_free(struct mm_struct * mm,pmd_t * pmdp)150 static inline void pmd_free(struct mm_struct *mm, pmd_t *pmdp)
151 {
152 pgtable_free(mm, virt_to_page(pmdp), L1_USER_PGTABLE_ORDER);
153 }
154
__pmd_free_tlb(struct mmu_gather * tlb,pmd_t * pmdp,unsigned long address)155 static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmdp,
156 unsigned long address)
157 {
158 __pgtable_free_tlb(tlb, virt_to_page(pmdp), address,
159 L1_USER_PGTABLE_ORDER);
160 }
161
162 #endif /* __tilegx__ */
163
164 #endif /* _ASM_TILE_PGALLOC_H */
165