]>
git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - include/linux/highmem.h
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_HIGHMEM_H
3 #define _LINUX_HIGHMEM_H
6 #include <linux/kernel.h>
9 #include <linux/uaccess.h>
10 #include <linux/hardirq.h>
12 #include <asm/cacheflush.h>
14 #ifndef ARCH_HAS_FLUSH_ANON_PAGE
15 static inline void flush_anon_page(struct vm_area_struct
*vma
, struct page
*page
, unsigned long vmaddr
)
20 #ifndef ARCH_HAS_FLUSH_KERNEL_DCACHE_PAGE
21 static inline void flush_kernel_dcache_page(struct page
*page
)
24 static inline void flush_kernel_vmap_range(void *vaddr
, int size
)
27 static inline void invalidate_kernel_vmap_range(void *vaddr
, int size
)
32 #include <asm/kmap_types.h>
35 #include <asm/highmem.h>
37 /* declarations for linux/mm/highmem.c */
38 unsigned int nr_free_highpages(void);
39 extern unsigned long totalhigh_pages
;
41 void kmap_flush_unused(void);
43 struct page
*kmap_to_page(void *addr
);
45 #else /* CONFIG_HIGHMEM */
47 static inline unsigned int nr_free_highpages(void) { return 0; }
49 static inline struct page
*kmap_to_page(void *addr
)
51 return virt_to_page(addr
);
54 #define totalhigh_pages 0UL
57 static inline void *kmap(struct page
*page
)
60 return page_address(page
);
63 static inline void kunmap(struct page
*page
)
67 static inline void *kmap_atomic(struct page
*page
)
71 return page_address(page
);
73 #define kmap_atomic_prot(page, prot) kmap_atomic(page)
75 static inline void __kunmap_atomic(void *addr
)
81 #define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
83 #define kmap_flush_unused() do {} while(0)
86 #endif /* CONFIG_HIGHMEM */
88 #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32)
90 DECLARE_PER_CPU(int, __kmap_atomic_idx
);
92 static inline int kmap_atomic_idx_push(void)
94 int idx
= __this_cpu_inc_return(__kmap_atomic_idx
) - 1;
96 #ifdef CONFIG_DEBUG_HIGHMEM
97 WARN_ON_ONCE(in_irq() && !irqs_disabled());
98 BUG_ON(idx
>= KM_TYPE_NR
);
103 static inline int kmap_atomic_idx(void)
105 return __this_cpu_read(__kmap_atomic_idx
) - 1;
108 static inline void kmap_atomic_idx_pop(void)
110 #ifdef CONFIG_DEBUG_HIGHMEM
111 int idx
= __this_cpu_dec_return(__kmap_atomic_idx
);
115 __this_cpu_dec(__kmap_atomic_idx
);
122 * Prevent people trying to call kunmap_atomic() as if it were kunmap()
123 * kunmap_atomic() should get the return value of kmap_atomic, not the page.
125 #define kunmap_atomic(addr) \
127 BUILD_BUG_ON(__same_type((addr), struct page *)); \
128 __kunmap_atomic(addr); \
132 /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */
133 #ifndef clear_user_highpage
134 static inline void clear_user_highpage(struct page
*page
, unsigned long vaddr
)
136 void *addr
= kmap_atomic(page
);
137 clear_user_page(addr
, vaddr
, page
);
142 #ifndef __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE
144 * __alloc_zeroed_user_highpage - Allocate a zeroed HIGHMEM page for a VMA with caller-specified movable GFP flags
145 * @movableflags: The GFP flags related to the pages future ability to move like __GFP_MOVABLE
146 * @vma: The VMA the page is to be allocated for
147 * @vaddr: The virtual address the page will be inserted into
149 * This function will allocate a page for a VMA but the caller is expected
150 * to specify via movableflags whether the page will be movable in the
153 * An architecture may override this function by defining
154 * __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE and providing their own
157 static inline struct page
*
158 __alloc_zeroed_user_highpage(gfp_t movableflags
,
159 struct vm_area_struct
*vma
,
162 struct page
*page
= alloc_page_vma(GFP_HIGHUSER
| movableflags
,
166 clear_user_highpage(page
, vaddr
);
173 * alloc_zeroed_user_highpage_movable - Allocate a zeroed HIGHMEM page for a VMA that the caller knows can move
174 * @vma: The VMA the page is to be allocated for
175 * @vaddr: The virtual address the page will be inserted into
177 * This function will allocate a page for a VMA that the caller knows will
178 * be able to migrate in the future using move_pages() or reclaimed
180 static inline struct page
*
181 alloc_zeroed_user_highpage_movable(struct vm_area_struct
*vma
,
184 return __alloc_zeroed_user_highpage(__GFP_MOVABLE
, vma
, vaddr
);
187 static inline void clear_highpage(struct page
*page
)
189 void *kaddr
= kmap_atomic(page
);
191 kunmap_atomic(kaddr
);
194 static inline void zero_user_segments(struct page
*page
,
195 unsigned start1
, unsigned end1
,
196 unsigned start2
, unsigned end2
)
198 void *kaddr
= kmap_atomic(page
);
200 BUG_ON(end1
> PAGE_SIZE
|| end2
> PAGE_SIZE
);
203 memset(kaddr
+ start1
, 0, end1
- start1
);
206 memset(kaddr
+ start2
, 0, end2
- start2
);
208 kunmap_atomic(kaddr
);
209 flush_dcache_page(page
);
212 static inline void zero_user_segment(struct page
*page
,
213 unsigned start
, unsigned end
)
215 zero_user_segments(page
, start
, end
, 0, 0);
218 static inline void zero_user(struct page
*page
,
219 unsigned start
, unsigned size
)
221 zero_user_segments(page
, start
, start
+ size
, 0, 0);
224 #ifndef __HAVE_ARCH_COPY_USER_HIGHPAGE
226 static inline void copy_user_highpage(struct page
*to
, struct page
*from
,
227 unsigned long vaddr
, struct vm_area_struct
*vma
)
231 vfrom
= kmap_atomic(from
);
232 vto
= kmap_atomic(to
);
233 copy_user_page(vto
, vfrom
, vaddr
, to
);
235 kunmap_atomic(vfrom
);
240 #ifndef __HAVE_ARCH_COPY_HIGHPAGE
242 static inline void copy_highpage(struct page
*to
, struct page
*from
)
246 vfrom
= kmap_atomic(from
);
247 vto
= kmap_atomic(to
);
248 copy_page(vto
, vfrom
);
250 kunmap_atomic(vfrom
);
255 #endif /* _LINUX_HIGHMEM_H */