1 #ifndef _LINUX_HIGHMEM_H
2 #define _LINUX_HIGHMEM_H
5 #include <linux/kernel.h>
8 #include <linux/uaccess.h>
9 #include <linux/hardirq.h>
11 #include <asm/cacheflush.h>
13 #ifndef ARCH_HAS_FLUSH_ANON_PAGE
14 static inline void flush_anon_page(struct vm_area_struct
*vma
, struct page
*page
, unsigned long vmaddr
)
19 #ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
20 static inline void flush_kernel_dcache_page(struct page
*page
)
23 static inline void flush_kernel_vmap_range(void *vaddr
, int size
)
26 static inline void invalidate_kernel_vmap_range(void *vaddr
, int size
)
31 #include <asm/kmap_types.h>
34 #include <asm/highmem.h>
36 /* declarations for linux/mm/highmem.c */
37 unsigned int nr_free_highpages(void);
38 extern unsigned long totalhigh_pages
;
40 void kmap_flush_unused(void);
42 #else /* CONFIG_HIGHMEM */
44 static inline unsigned int nr_free_highpages(void) { return 0; }
46 #define totalhigh_pages 0UL
49 static inline void *kmap(struct page
*page
)
52 return page_address(page
);
55 static inline void kunmap(struct page
*page
)
59 static inline void *kmap_atomic(struct page
*page
)
62 return page_address(page
);
64 #define kmap_atomic_prot(page, prot) kmap_atomic(page)
66 static inline void __kunmap_atomic(void *addr
)
71 #define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
72 #define kmap_atomic_to_page(ptr) virt_to_page(ptr)
74 #define kmap_flush_unused() do {} while(0)
77 #endif /* CONFIG_HIGHMEM */
79 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
81 DECLARE_PER_CPU(int, __kmap_atomic_idx
);
83 static inline int kmap_atomic_idx_push(void)
85 int idx
= __this_cpu_inc_return(__kmap_atomic_idx
) - 1;
87 #ifdef CONFIG_DEBUG_HIGHMEM
88 WARN_ON_ONCE(in_irq() && !irqs_disabled());
89 BUG_ON(idx
> KM_TYPE_NR
);
94 static inline int kmap_atomic_idx(void)
96 return __this_cpu_read(__kmap_atomic_idx
) - 1;
99 static inline void kmap_atomic_idx_pop(void)
101 #ifdef CONFIG_DEBUG_HIGHMEM
102 int idx
= __this_cpu_dec_return(__kmap_atomic_idx
);
106 __this_cpu_dec(__kmap_atomic_idx
);
114 * kmap_atomic() and kunmap_atomic() with two arguments are deprecated.
115 * We only keep them for backward compatibility, any usage of them
119 #define PASTE(a, b) a ## b
120 #define PASTE2(a, b) PASTE(a, b)
122 #define NARG_(_2, _1, n, ...) n
123 #define NARG(...) NARG_(__VA_ARGS__, 2, 1, :)
125 static inline void __deprecated
*kmap_atomic_deprecated(struct page
*page
,
128 return kmap_atomic(page
);
131 #define kmap_atomic1(...) kmap_atomic(__VA_ARGS__)
132 #define kmap_atomic2(...) kmap_atomic_deprecated(__VA_ARGS__)
133 #define kmap_atomic(...) PASTE2(kmap_atomic, NARG(__VA_ARGS__)(__VA_ARGS__))
135 static inline void __deprecated
__kunmap_atomic_deprecated(void *addr
,
138 __kunmap_atomic(addr
);
142 * Prevent people trying to call kunmap_atomic() as if it were kunmap()
143 * kunmap_atomic() should get the return value of kmap_atomic, not the page.
145 #define kunmap_atomic_deprecated(addr, km) \
147 BUILD_BUG_ON(__same_type((addr), struct page *)); \
148 __kunmap_atomic_deprecated(addr, km); \
151 #define kunmap_atomic_withcheck(addr) \
153 BUILD_BUG_ON(__same_type((addr), struct page *)); \
154 __kunmap_atomic(addr); \
157 #define kunmap_atomic1(...) kunmap_atomic_withcheck(__VA_ARGS__)
158 #define kunmap_atomic2(...) kunmap_atomic_deprecated(__VA_ARGS__)
159 #define kunmap_atomic(...) PASTE2(kunmap_atomic, NARG(__VA_ARGS__)(__VA_ARGS__))
160 /**** End of C pre-processor tricks for deprecated macros ****/
162 /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
163 #ifndef clear_user_highpage
164 static inline void clear_user_highpage(struct page
*page
, unsigned long vaddr
)
166 void *addr
= kmap_atomic(page
);
167 clear_user_page(addr
, vaddr
, page
);
172 #ifndef __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
174 * __alloc_zeroed_user_highpage - Allocate a zeroed HIGHMEM page for a VMA with caller-specified movable GFP flags
175 * @movableflags: The GFP flags related to the pages future ability to move like __GFP_MOVABLE
176 * @vma: The VMA the page is to be allocated for
177 * @vaddr: The virtual address the page will be inserted into
179 * This function will allocate a page for a VMA but the caller is expected
180 * to specify via movableflags whether the page will be movable in the
183 * An architecture may override this function by defining
184 * __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE and providing their own
187 static inline struct page
*
188 __alloc_zeroed_user_highpage(gfp_t movableflags
,
189 struct vm_area_struct
*vma
,
192 struct page
*page
= alloc_page_vma(GFP_HIGHUSER
| movableflags
,
196 clear_user_highpage(page
, vaddr
);
203 * alloc_zeroed_user_highpage_movable - Allocate a zeroed HIGHMEM page for a VMA that the caller knows can move
204 * @vma: The VMA the page is to be allocated for
205 * @vaddr: The virtual address the page will be inserted into
207 * This function will allocate a page for a VMA that the caller knows will
208 * be able to migrate in the future using move_pages() or reclaimed
210 static inline struct page
*
211 alloc_zeroed_user_highpage_movable(struct vm_area_struct
*vma
,
214 return __alloc_zeroed_user_highpage(__GFP_MOVABLE
, vma
, vaddr
);
217 static inline void clear_highpage(struct page
*page
)
219 void *kaddr
= kmap_atomic(page
);
221 kunmap_atomic(kaddr
);
224 static inline void zero_user_segments(struct page
*page
,
225 unsigned start1
, unsigned end1
,
226 unsigned start2
, unsigned end2
)
228 void *kaddr
= kmap_atomic(page
);
230 BUG_ON(end1
> PAGE_SIZE
|| end2
> PAGE_SIZE
);
233 memset(kaddr
+ start1
, 0, end1
- start1
);
236 memset(kaddr
+ start2
, 0, end2
- start2
);
238 kunmap_atomic(kaddr
);
239 flush_dcache_page(page
);
242 static inline void zero_user_segment(struct page
*page
,
243 unsigned start
, unsigned end
)
245 zero_user_segments(page
, start
, end
, 0, 0);
248 static inline void zero_user(struct page
*page
,
249 unsigned start
, unsigned size
)
251 zero_user_segments(page
, start
, start
+ size
, 0, 0);
254 static inline void __deprecated
memclear_highpage_flush(struct page
*page
,
255 unsigned int offset
, unsigned int size
)
257 zero_user(page
, offset
, size
);
260 #ifndef __HAVE_ARCH_COPY_USER_HIGHPAGE
262 static inline void copy_user_highpage(struct page
*to
, struct page
*from
,
263 unsigned long vaddr
, struct vm_area_struct
*vma
)
267 vfrom
= kmap_atomic(from
);
268 vto
= kmap_atomic(to
);
269 copy_user_page(vto
, vfrom
, vaddr
, to
);
271 kunmap_atomic(vfrom
);
276 static inline void copy_highpage(struct page
*to
, struct page
*from
)
280 vfrom
= kmap_atomic(from
);
281 vto
= kmap_atomic(to
);
282 copy_page(vto
, vfrom
);
284 kunmap_atomic(vfrom
);
287 #endif /* _LINUX_HIGHMEM_H */