1 #ifndef _LINUX_HIGHMEM_H
2 #define _LINUX_HIGHMEM_H
5 #include <linux/kernel.h>
7 #include <linux/uaccess.h>
8 #include <linux/hardirq.h>
10 #include <asm/cacheflush.h>
12 #ifndef ARCH_HAS_FLUSH_ANON_PAGE
13 static inline void flush_anon_page(struct vm_area_struct *vma, struct page *page, unsigned long vmaddr)
18 #ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
19 static inline void flush_kernel_dcache_page(struct page *page)
22 static inline void flush_kernel_vmap_range(void *vaddr, int size)
25 static inline void invalidate_kernel_vmap_range(void *vaddr, int size)
30 #include <asm/kmap_types.h>
33 #include <asm/highmem.h>
35 /* declarations for linux/mm/highmem.c */
36 unsigned int nr_free_highpages(void);
37 extern unsigned long totalhigh_pages;
39 void kmap_flush_unused(void);
41 #else /* CONFIG_HIGHMEM */
43 static inline unsigned int nr_free_highpages(void) { return 0; }
45 #define totalhigh_pages 0UL
48 static inline void *kmap(struct page *page)
51 return page_address(page);
54 static inline void kunmap(struct page *page)
58 static inline void *kmap_atomic(struct page *page)
61 return page_address(page);
63 #define kmap_atomic_prot(page, prot) kmap_atomic(page)
65 static inline void __kunmap_atomic(void *addr)
70 #define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
71 #define kmap_atomic_to_page(ptr) virt_to_page(ptr)
73 #define kmap_flush_unused() do {} while(0)
76 #endif /* CONFIG_HIGHMEM */
78 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
80 DECLARE_PER_CPU(int, __kmap_atomic_idx);
82 static inline int kmap_atomic_idx_push(void)
84 int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1;
86 #ifdef CONFIG_DEBUG_HIGHMEM
87 WARN_ON_ONCE(in_irq() && !irqs_disabled());
88 BUG_ON(idx > KM_TYPE_NR);
93 static inline int kmap_atomic_idx(void)
95 return __this_cpu_read(__kmap_atomic_idx) - 1;
98 static inline void kmap_atomic_idx_pop(void)
100 #ifdef CONFIG_DEBUG_HIGHMEM
101 int idx = __this_cpu_dec_return(__kmap_atomic_idx);
105 __this_cpu_dec(__kmap_atomic_idx);
113 * kmap_atomic() and kunmap_atomic() with two arguments are deprecated.
114 * We only keep them for backward compatibility, any usage of them
118 #define PASTE(a, b) a ## b
119 #define PASTE2(a, b) PASTE(a, b)
121 #define NARG_(_2, _1, n, ...) n
122 #define NARG(...) NARG_(__VA_ARGS__, 2, 1, :)
124 static inline void __deprecated *kmap_atomic_deprecated(struct page *page,
127 return kmap_atomic(page);
130 #define kmap_atomic1(...) kmap_atomic(__VA_ARGS__)
131 #define kmap_atomic2(...) kmap_atomic_deprecated(__VA_ARGS__)
132 #define kmap_atomic(...) PASTE2(kmap_atomic, NARG(__VA_ARGS__)(__VA_ARGS__))
134 static inline void __deprecated __kunmap_atomic_deprecated(void *addr,
137 __kunmap_atomic(addr);
141 * Prevent people trying to call kunmap_atomic() as if it were kunmap()
142 * kunmap_atomic() should get the return value of kmap_atomic, not the page.
144 #define kunmap_atomic_deprecated(addr, km) \
146 BUILD_BUG_ON(__same_type((addr), struct page *)); \
147 __kunmap_atomic_deprecated(addr, km); \
150 #define kunmap_atomic_withcheck(addr) \
152 BUILD_BUG_ON(__same_type((addr), struct page *)); \
153 __kunmap_atomic(addr); \
156 #define kunmap_atomic1(...) kunmap_atomic_withcheck(__VA_ARGS__)
157 #define kunmap_atomic2(...) kunmap_atomic_deprecated(__VA_ARGS__)
158 #define kunmap_atomic(...) PASTE2(kunmap_atomic, NARG(__VA_ARGS__)(__VA_ARGS__))
159 /**** End of C pre-processor tricks for deprecated macros ****/
161 /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
162 #ifndef clear_user_highpage
163 static inline void clear_user_highpage(struct page *page, unsigned long vaddr)
165 void *addr = kmap_atomic(page);
166 clear_user_page(addr, vaddr, page);
171 #ifndef __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
173 * __alloc_zeroed_user_highpage - Allocate a zeroed HIGHMEM page for a VMA with caller-specified movable GFP flags
174 * @movableflags: The GFP flags related to the pages future ability to move like __GFP_MOVABLE
175 * @vma: The VMA the page is to be allocated for
176 * @vaddr: The virtual address the page will be inserted into
178 * This function will allocate a page for a VMA but the caller is expected
179 * to specify via movableflags whether the page will be movable in the
182 * An architecture may override this function by defining
183 * __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE and providing their own
186 static inline struct page *
187 __alloc_zeroed_user_highpage(gfp_t movableflags,
188 struct vm_area_struct *vma,
191 struct page *page = alloc_page_vma(GFP_HIGHUSER | movableflags,
195 clear_user_highpage(page, vaddr);
202 * alloc_zeroed_user_highpage_movable - Allocate a zeroed HIGHMEM page for a VMA that the caller knows can move
203 * @vma: The VMA the page is to be allocated for
204 * @vaddr: The virtual address the page will be inserted into
206 * This function will allocate a page for a VMA that the caller knows will
207 * be able to migrate in the future using move_pages() or reclaimed
209 static inline struct page *
210 alloc_zeroed_user_highpage_movable(struct vm_area_struct *vma,
213 return __alloc_zeroed_user_highpage(__GFP_MOVABLE, vma, vaddr);
216 static inline void clear_highpage(struct page *page)
218 void *kaddr = kmap_atomic(page);
220 kunmap_atomic(kaddr);
223 static inline void zero_user_segments(struct page *page,
224 unsigned start1, unsigned end1,
225 unsigned start2, unsigned end2)
227 void *kaddr = kmap_atomic(page);
229 BUG_ON(end1 > PAGE_SIZE || end2 > PAGE_SIZE);
232 memset(kaddr + start1, 0, end1 - start1);
235 memset(kaddr + start2, 0, end2 - start2);
237 kunmap_atomic(kaddr);
238 flush_dcache_page(page);
241 static inline void zero_user_segment(struct page *page,
242 unsigned start, unsigned end)
244 zero_user_segments(page, start, end, 0, 0);
247 static inline void zero_user(struct page *page,
248 unsigned start, unsigned size)
250 zero_user_segments(page, start, start + size, 0, 0);
253 static inline void __deprecated memclear_highpage_flush(struct page *page,
254 unsigned int offset, unsigned int size)
256 zero_user(page, offset, size);
259 #ifndef __HAVE_ARCH_COPY_USER_HIGHPAGE
261 static inline void copy_user_highpage(struct page *to, struct page *from,
262 unsigned long vaddr, struct vm_area_struct *vma)
266 vfrom = kmap_atomic(from);
267 vto = kmap_atomic(to);
268 copy_user_page(vto, vfrom, vaddr, to);
270 kunmap_atomic(vfrom);
275 static inline void copy_highpage(struct page *to, struct page *from)
279 vfrom = kmap_atomic(from);
280 vto = kmap_atomic(to);
281 copy_page(vto, vfrom);
283 kunmap_atomic(vfrom);
286 #endif /* _LINUX_HIGHMEM_H */