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8#include <linux/kernel.h>
9#include <linux/mm.h>
10#include <linux/swap.h>
11#include <linux/pagemap.h>
12
13#include <asm/pgalloc.h>
14#include <asm/pgtable.h>
15#include <asm/page.h>
16#include <asm/tlbflush.h>
17
18
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21
22
23
24static inline void io_remap_pte_range(struct mm_struct *mm, pte_t * pte,
25 unsigned long address,
26 unsigned long size,
27 unsigned long offset, pgprot_t prot,
28 int space)
29{
30 unsigned long end;
31
32
33 offset &= ~0x1UL;
34 address &= ~PMD_MASK;
35 end = address + size;
36 if (end > PMD_SIZE)
37 end = PMD_SIZE;
38 do {
39 pte_t entry;
40 unsigned long curend = address + PAGE_SIZE;
41
42 entry = mk_pte_io(offset, prot, space, PAGE_SIZE);
43 if (!(address & 0xffff)) {
44 if (PAGE_SIZE < (4 * 1024 * 1024) &&
45 !(address & 0x3fffff) &&
46 !(offset & 0x3ffffe) &&
47 end >= address + 0x400000) {
48 entry = mk_pte_io(offset, prot, space,
49 4 * 1024 * 1024);
50 curend = address + 0x400000;
51 offset += 0x400000;
52 } else if (PAGE_SIZE < (512 * 1024) &&
53 !(address & 0x7ffff) &&
54 !(offset & 0x7fffe) &&
55 end >= address + 0x80000) {
56 entry = mk_pte_io(offset, prot, space,
57 512 * 1024 * 1024);
58 curend = address + 0x80000;
59 offset += 0x80000;
60 } else if (PAGE_SIZE < (64 * 1024) &&
61 !(offset & 0xfffe) &&
62 end >= address + 0x10000) {
63 entry = mk_pte_io(offset, prot, space,
64 64 * 1024);
65 curend = address + 0x10000;
66 offset += 0x10000;
67 } else
68 offset += PAGE_SIZE;
69 } else
70 offset += PAGE_SIZE;
71
72 if (pte_write(entry))
73 entry = pte_mkdirty(entry);
74 do {
75 BUG_ON(!pte_none(*pte));
76 set_pte_at(mm, address, pte, entry);
77 address += PAGE_SIZE;
78 pte_val(entry) += PAGE_SIZE;
79 pte++;
80 } while (address < curend);
81 } while (address < end);
82}
83
84static inline int io_remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned long address, unsigned long size,
85 unsigned long offset, pgprot_t prot, int space)
86{
87 unsigned long end;
88
89 address &= ~PGDIR_MASK;
90 end = address + size;
91 if (end > PGDIR_SIZE)
92 end = PGDIR_SIZE;
93 offset -= address;
94 do {
95 pte_t *pte = pte_alloc_map(mm, NULL, pmd, address);
96 if (!pte)
97 return -ENOMEM;
98 io_remap_pte_range(mm, pte, address, end - address, address + offset, prot, space);
99 pte_unmap(pte);
100 address = (address + PMD_SIZE) & PMD_MASK;
101 pmd++;
102 } while (address < end);
103 return 0;
104}
105
106static inline int io_remap_pud_range(struct mm_struct *mm, pud_t * pud, unsigned long address, unsigned long size,
107 unsigned long offset, pgprot_t prot, int space)
108{
109 unsigned long end;
110
111 address &= ~PUD_MASK;
112 end = address + size;
113 if (end > PUD_SIZE)
114 end = PUD_SIZE;
115 offset -= address;
116 do {
117 pmd_t *pmd = pmd_alloc(mm, pud, address);
118 if (!pud)
119 return -ENOMEM;
120 io_remap_pmd_range(mm, pmd, address, end - address, address + offset, prot, space);
121 address = (address + PUD_SIZE) & PUD_MASK;
122 pud++;
123 } while (address < end);
124 return 0;
125}
126
127int io_remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
128 unsigned long pfn, unsigned long size, pgprot_t prot)
129{
130 int error = 0;
131 pgd_t * dir;
132 unsigned long beg = from;
133 unsigned long end = from + size;
134 struct mm_struct *mm = vma->vm_mm;
135 int space = GET_IOSPACE(pfn);
136 unsigned long offset = GET_PFN(pfn) << PAGE_SHIFT;
137 unsigned long phys_base;
138
139 phys_base = offset | (((unsigned long) space) << 32UL);
140
141
142 vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP;
143 vma->vm_pgoff = phys_base >> PAGE_SHIFT;
144
145 offset -= from;
146 dir = pgd_offset(mm, from);
147 flush_cache_range(vma, beg, end);
148
149 while (from < end) {
150 pud_t *pud = pud_alloc(mm, dir, from);
151 error = -ENOMEM;
152 if (!pud)
153 break;
154 error = io_remap_pud_range(mm, pud, from, end - from, offset + from, prot, space);
155 if (error)
156 break;
157 from = (from + PGDIR_SIZE) & PGDIR_MASK;
158 dir++;
159 }
160
161 flush_tlb_range(vma, beg, end);
162 return error;
163}
164EXPORT_SYMBOL(io_remap_pfn_range);
165
