Commit | Line | Data |
---|---|---|
185aed75 PM |
1 | /* |
2 | * arch/sh/mm/mmap.c | |
3 | * | |
ee1acbfa | 4 | * Copyright (C) 2008 - 2009 Paul Mundt |
185aed75 PM |
5 | * |
6 | * This file is subject to the terms and conditions of the GNU General Public | |
7 | * License. See the file "COPYING" in the main directory of this archive | |
8 | * for more details. | |
9 | */ | |
10 | #include <linux/io.h> | |
11 | #include <linux/mm.h> | |
4a4a9be3 PM |
12 | #include <linux/mman.h> |
13 | #include <linux/module.h> | |
185aed75 | 14 | #include <asm/page.h> |
4a4a9be3 PM |
15 | #include <asm/processor.h> |
16 | ||
4a4a9be3 PM |
17 | unsigned long shm_align_mask = PAGE_SIZE - 1; /* Sane caches */ |
18 | EXPORT_SYMBOL(shm_align_mask); | |
19 | ||
dde5e3ff | 20 | #ifdef CONFIG_MMU |
4a4a9be3 PM |
21 | /* |
22 | * To avoid cache aliases, we map the shared page with same color. | |
23 | */ | |
ee1acbfa PM |
24 | static inline unsigned long COLOUR_ALIGN(unsigned long addr, |
25 | unsigned long pgoff) | |
26 | { | |
27 | unsigned long base = (addr + shm_align_mask) & ~shm_align_mask; | |
28 | unsigned long off = (pgoff << PAGE_SHIFT) & shm_align_mask; | |
29 | ||
30 | return base + off; | |
31 | } | |
32 | ||
4a4a9be3 PM |
33 | unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr, |
34 | unsigned long len, unsigned long pgoff, unsigned long flags) | |
35 | { | |
36 | struct mm_struct *mm = current->mm; | |
37 | struct vm_area_struct *vma; | |
4a4a9be3 | 38 | int do_colour_align; |
b4265f12 | 39 | struct vm_unmapped_area_info info; |
4a4a9be3 PM |
40 | |
41 | if (flags & MAP_FIXED) { | |
42 | /* We do not accept a shared mapping if it would violate | |
43 | * cache aliasing constraints. | |
44 | */ | |
e77414e0 AV |
45 | if ((flags & MAP_SHARED) && |
46 | ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask)) | |
4a4a9be3 PM |
47 | return -EINVAL; |
48 | return addr; | |
49 | } | |
50 | ||
51 | if (unlikely(len > TASK_SIZE)) | |
52 | return -ENOMEM; | |
53 | ||
54 | do_colour_align = 0; | |
55 | if (filp || (flags & MAP_SHARED)) | |
56 | do_colour_align = 1; | |
57 | ||
58 | if (addr) { | |
59 | if (do_colour_align) | |
60 | addr = COLOUR_ALIGN(addr, pgoff); | |
61 | else | |
62 | addr = PAGE_ALIGN(addr); | |
63 | ||
64 | vma = find_vma(mm, addr); | |
65 | if (TASK_SIZE - len >= addr && | |
66 | (!vma || addr + len <= vma->vm_start)) | |
67 | return addr; | |
68 | } | |
69 | ||
b4265f12 ML |
70 | info.flags = 0; |
71 | info.length = len; | |
72 | info.low_limit = TASK_UNMAPPED_BASE; | |
73 | info.high_limit = TASK_SIZE; | |
74 | info.align_mask = do_colour_align ? (PAGE_MASK & shm_align_mask) : 0; | |
75 | info.align_offset = pgoff << PAGE_SHIFT; | |
76 | return vm_unmapped_area(&info); | |
4a4a9be3 | 77 | } |
ee1acbfa PM |
78 | |
79 | unsigned long | |
80 | arch_get_unmapped_area_topdown(struct file *filp, const unsigned long addr0, | |
81 | const unsigned long len, const unsigned long pgoff, | |
82 | const unsigned long flags) | |
83 | { | |
84 | struct vm_area_struct *vma; | |
85 | struct mm_struct *mm = current->mm; | |
86 | unsigned long addr = addr0; | |
87 | int do_colour_align; | |
b4265f12 | 88 | struct vm_unmapped_area_info info; |
ee1acbfa PM |
89 | |
90 | if (flags & MAP_FIXED) { | |
91 | /* We do not accept a shared mapping if it would violate | |
92 | * cache aliasing constraints. | |
93 | */ | |
94 | if ((flags & MAP_SHARED) && | |
95 | ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask)) | |
96 | return -EINVAL; | |
97 | return addr; | |
98 | } | |
99 | ||
100 | if (unlikely(len > TASK_SIZE)) | |
101 | return -ENOMEM; | |
102 | ||
103 | do_colour_align = 0; | |
104 | if (filp || (flags & MAP_SHARED)) | |
105 | do_colour_align = 1; | |
106 | ||
107 | /* requesting a specific address */ | |
108 | if (addr) { | |
109 | if (do_colour_align) | |
110 | addr = COLOUR_ALIGN(addr, pgoff); | |
111 | else | |
112 | addr = PAGE_ALIGN(addr); | |
113 | ||
114 | vma = find_vma(mm, addr); | |
115 | if (TASK_SIZE - len >= addr && | |
116 | (!vma || addr + len <= vma->vm_start)) | |
117 | return addr; | |
118 | } | |
119 | ||
b4265f12 ML |
120 | info.flags = VM_UNMAPPED_AREA_TOPDOWN; |
121 | info.length = len; | |
122 | info.low_limit = PAGE_SIZE; | |
123 | info.high_limit = mm->mmap_base; | |
124 | info.align_mask = do_colour_align ? (PAGE_MASK & shm_align_mask) : 0; | |
125 | info.align_offset = pgoff << PAGE_SHIFT; | |
126 | addr = vm_unmapped_area(&info); | |
ee1acbfa | 127 | |
ee1acbfa PM |
128 | /* |
129 | * A failed mmap() very likely causes application failure, | |
130 | * so fall back to the bottom-up function here. This scenario | |
131 | * can happen with large stack limits and large mmap() | |
132 | * allocations. | |
133 | */ | |
b4265f12 ML |
134 | if (addr & ~PAGE_MASK) { |
135 | VM_BUG_ON(addr != -ENOMEM); | |
136 | info.flags = 0; | |
137 | info.low_limit = TASK_UNMAPPED_BASE; | |
138 | info.high_limit = TASK_SIZE; | |
139 | addr = vm_unmapped_area(&info); | |
140 | } | |
ee1acbfa PM |
141 | |
142 | return addr; | |
143 | } | |
4a4a9be3 | 144 | #endif /* CONFIG_MMU */ |
185aed75 PM |
145 | |
146 | /* | |
147 | * You really shouldn't be using read() or write() on /dev/mem. This | |
148 | * might go away in the future. | |
149 | */ | |
7e6735c3 | 150 | int valid_phys_addr_range(phys_addr_t addr, size_t count) |
185aed75 | 151 | { |
10840f03 | 152 | if (addr < __MEMORY_START) |
185aed75 PM |
153 | return 0; |
154 | if (addr + count > __pa(high_memory)) | |
155 | return 0; | |
156 | ||
157 | return 1; | |
158 | } | |
159 | ||
160 | int valid_mmap_phys_addr_range(unsigned long pfn, size_t size) | |
161 | { | |
162 | return 1; | |
163 | } |