1#ifndef _LINUX_HIGHMEM_H
2#define _LINUX_HIGHMEM_H
3
4#include <linux/fs.h>
5#include <linux/kernel.h>
6#include <linux/mm.h>
7#include <linux/uaccess.h>
8#include <linux/hardirq.h>
9
10#include <asm/cacheflush.h>
11
12#ifndef ARCH_HAS_FLUSH_ANON_PAGE
13static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
14{
15}
16#endif
17
18#ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
19static inline void flush_kernel_dcache_page(struct page *page)
20{
21}
22static inline void flush_kernel_vmap_range(void *vaddr, int size)
23{
24}
25static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
26{
27}
28#endif
29
30#include <asm/kmap_types.h>
31
32#ifdef CONFIG_HIGHMEM
33#include <asm/highmem.h>
34
35
36unsigned int nr_free_highpages(void);
37extern unsigned long totalhigh_pages;
38
39void kmap_flush_unused(void);
40
41#else
42
43static inline unsigned int nr_free_highpages(void) { return 0; }
44
45#define totalhigh_pages 0UL
46
47#ifndef ARCH_HAS_KMAP
48static inline void *kmap(struct page *page)
49{
50 might_sleep();
51 return page_address(page);
52}
53
54static inline void kunmap(struct page *page)
55{
56}
57
58static inline void *__kmap_atomic(struct page *page)
59{
60 pagefault_disable();
61 return page_address(page);
62}
63#define kmap_atomic_prot(page, prot) __kmap_atomic(page)
64
65static inline void __kunmap_atomic(void *addr)
66{
67 pagefault_enable();
68}
69
70#define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
71#define kmap_atomic_to_page(ptr) virt_to_page(ptr)
72
73#define kmap_flush_unused() do {} while(0)
74#endif
75
76#endif
77
78#if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
79
80DECLARE_PER_CPU(int, __kmap_atomic_idx);
81
82static inline int kmap_atomic_idx_push(void)
83{
84 int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
85
86#ifdef CONFIG_DEBUG_HIGHMEM
87 WARN_ON_ONCE(in_irq() && !irqs_disabled());
88 BUG_ON(idx > KM_TYPE_NR);
89#endif
90 return idx;
91}
92
93static inline int kmap_atomic_idx(void)
94{
95 return __this_cpu_read(__kmap_atomic_idx) - 1;
96}
97
98static inline void kmap_atomic_idx_pop(void)
99{
100#ifdef CONFIG_DEBUG_HIGHMEM
101 int idx = __this_cpu_dec_return(__kmap_atomic_idx);
102
103 BUG_ON(idx < 0);
104#else
105 __this_cpu_dec(__kmap_atomic_idx);
106#endif
107}
108
109#endif
110
111
112
113
114#define kmap_atomic(page, args...) __kmap_atomic(page)
115
116
117
118
119
120#define kunmap_atomic(addr, args...) \
121do { \
122 BUILD_BUG_ON(__same_type((addr), struct page *)); \
123 __kunmap_atomic(addr); \
124} while (0)
125
126
127#ifndef clear_user_highpage
128static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
129{
130 void *addr = kmap_atomic(page, KM_USER0);
131 clear_user_page(addr, vaddr, page);
132 kunmap_atomic(addr, KM_USER0);
133}
134#endif
135
136#ifndef __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151static inline struct page *
152__alloc_zeroed_user_highpage(gfp_t movableflags,
153 struct vm_area_struct *vma,
154 unsigned long vaddr)
155{
156 struct page *page = alloc_page_vma(GFP_HIGHUSER | movableflags,
157 vma, vaddr);
158
159 if (page)
160 clear_user_highpage(page, vaddr);
161
162 return page;
163}
164#endif
165
166
167
168
169
170
171
172
173
174static inline struct page *
175alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma,
176 unsigned long vaddr)
177{
178 return __alloc_zeroed_user_highpage(__GFP_MOVABLE, vma, vaddr);
179}
180
181static inline void clear_highpage(struct page *page)
182{
183 void *kaddr = kmap_atomic(page, KM_USER0);
184 clear_page(kaddr);
185 kunmap_atomic(kaddr, KM_USER0);
186}
187
188static inline void zero_user_segments(struct page *page,
189 unsigned start1, unsigned end1,
190 unsigned start2, unsigned end2)
191{
192 void *kaddr = kmap_atomic(page, KM_USER0);
193
194 BUG_ON(end1 > PAGE_SIZE || end2 > PAGE_SIZE);
195
196 if (end1 > start1)
197 memset(kaddr + start1, 0, end1 - start1);
198
199 if (end2 > start2)
200 memset(kaddr + start2, 0, end2 - start2);
201
202 kunmap_atomic(kaddr, KM_USER0);
203 flush_dcache_page(page);
204}
205
206static inline void zero_user_segment(struct page *page,
207 unsigned start, unsigned end)
208{
209 zero_user_segments(page, start, end, 0, 0);
210}
211
212static inline void zero_user(struct page *page,
213 unsigned start, unsigned size)
214{
215 zero_user_segments(page, start, start + size, 0, 0);
216}
217
218static inline void __deprecated memclear_highpage_flush(struct page *page,
219 unsigned int offset, unsigned int size)
220{
221 zero_user(page, offset, size);
222}
223
224#ifndef __HAVE_ARCH_COPY_USER_HIGHPAGE
225
226static inline void copy_user_highpage(struct page *to, struct page *from,
227 unsigned long vaddr, struct vm_area_struct *vma)
228{
229 char *vfrom, *vto;
230
231 vfrom = kmap_atomic(from, KM_USER0);
232 vto = kmap_atomic(to, KM_USER1);
233 copy_user_page(vto, vfrom, vaddr, to);
234 kunmap_atomic(vto, KM_USER1);
235 kunmap_atomic(vfrom, KM_USER0);
236}
237
238#endif
239
240static inline void copy_highpage(struct page *to, struct page *from)
241{
242 char *vfrom, *vto;
243
244 vfrom = kmap_atomic(from, KM_USER0);
245 vto = kmap_atomic(to, KM_USER1);
246 copy_page(vto, vfrom);
247 kunmap_atomic(vto, KM_USER1);
248 kunmap_atomic(vfrom, KM_USER0);
249}
250
251#endif
252