projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | #ifndef _LINUX_HIGHMEM_H |
| 2 | #define _LINUX_HIGHMEM_H | |
| 3 | ||
| 4 | #include <linux/config.h> | |
| 5 | #include <linux/fs.h> | |
| 6 | #include <linux/mm.h> | |
| 7 | ||
| 8 | #include <asm/cacheflush.h> | |
| 9 | ||
| 10 | #ifdef CONFIG_HIGHMEM | |
| 11 | ||
| 12 | #include <asm/highmem.h> | |
| 13 | ||
| 14 | /* declarations for linux/mm/highmem.c */ | |
| 15 | unsigned int nr_free_highpages(void); | |
| 16 | ||
| 17 | #else /* CONFIG_HIGHMEM */ | |
| 18 | ||
| 19 | static inline unsigned int nr_free_highpages(void) { return 0; } | |
| 20 | ||
| 21 | static inline void *kmap(struct page *page) | |
| 22 | { | |
| 23 | might_sleep(); | |
| 24 | return page_address(page); | |
| 25 | } | |
| 26 | ||
| 27 | #define kunmap(page) do { (void) (page); } while (0) | |
| 28 | ||
| 29 | #define kmap_atomic(page, idx) page_address(page) | |
| 30 | #define kunmap_atomic(addr, idx) do { } while (0) | |
| 60e64d46 | 31 | #define kmap_atomic_pfn(pfn, idx) page_address(pfn_to_page(pfn)) |
| 1da177e4 LT |
32 | #define kmap_atomic_to_page(ptr) virt_to_page(ptr) |
| 33 | ||
| 34 | #endif /* CONFIG_HIGHMEM */ | |
| 35 | ||
| 36 | /* when CONFIG_HIGHMEM is not set these will be plain clear/copy_page */ | |
| 37 | static inline void clear_user_highpage(struct page *page, unsigned long vaddr) | |
| 38 | { | |
| 39 | void *addr = kmap_atomic(page, KM_USER0); | |
| 40 | clear_user_page(addr, vaddr, page); | |
| 41 | kunmap_atomic(addr, KM_USER0); | |
| 42 | /* Make sure this page is cleared on other CPU's too before using it */ | |
| 43 | smp_wmb(); | |
| 44 | } | |
| 45 | ||
| 46 | #ifndef __HAVE_ARCH_ALLOC_ZEROED_USER_HIGHPAGE | |
| 47 | static inline struct page * | |
| 48 | alloc_zeroed_user_highpage(struct vm_area_struct *vma, unsigned long vaddr) | |
| 49 | { | |
| 50 | struct page *page = alloc_page_vma(GFP_HIGHUSER, vma, vaddr); | |
| 51 | ||
| 52 | if (page) | |
| 53 | clear_user_highpage(page, vaddr); | |
| 54 | ||
| 55 | return page; | |
| 56 | } | |
| 57 | #endif | |
| 58 | ||
| 59 | static inline void clear_highpage(struct page *page) | |
| 60 | { | |
| 61 | void *kaddr = kmap_atomic(page, KM_USER0); | |
| 62 | clear_page(kaddr); | |
| 63 | kunmap_atomic(kaddr, KM_USER0); | |
| 64 | } | |
| 65 | ||
| 66 | /* | |
| 67 | * Same but also flushes aliased cache contents to RAM. | |
| 68 | */ | |
| 69 | static inline void memclear_highpage_flush(struct page *page, unsigned int offset, unsigned int size) | |
| 70 | { | |
| 71 | void *kaddr; | |
| 72 | ||
| 73 | BUG_ON(offset + size > PAGE_SIZE); | |
| 74 | ||
| 75 | kaddr = kmap_atomic(page, KM_USER0); | |
| 76 | memset((char *)kaddr + offset, 0, size); | |
| 77 | flush_dcache_page(page); | |
| 78 | kunmap_atomic(kaddr, KM_USER0); | |
| 79 | } | |
| 80 | ||
| 81 | static inline void copy_user_highpage(struct page *to, struct page *from, unsigned long vaddr) | |
| 82 | { | |
| 83 | char *vfrom, *vto; | |
| 84 | ||
| 85 | vfrom = kmap_atomic(from, KM_USER0); | |
| 86 | vto = kmap_atomic(to, KM_USER1); | |
| 87 | copy_user_page(vto, vfrom, vaddr, to); | |
| 88 | kunmap_atomic(vfrom, KM_USER0); | |
| 89 | kunmap_atomic(vto, KM_USER1); | |
| 90 | /* Make sure this page is cleared on other CPU's too before using it */ | |
| 91 | smp_wmb(); | |
| 92 | } | |
| 93 | ||
| 94 | static inline void copy_highpage(struct page *to, struct page *from) | |
| 95 | { | |
| 96 | char *vfrom, *vto; | |
| 97 | ||
| 98 | vfrom = kmap_atomic(from, KM_USER0); | |
| 99 | vto = kmap_atomic(to, KM_USER1); | |
| 100 | copy_page(vto, vfrom); | |
| 101 | kunmap_atomic(vfrom, KM_USER0); | |
| 102 | kunmap_atomic(vto, KM_USER1); | |
| 103 | } | |
| 104 | ||
| 105 | #endif /* _LINUX_HIGHMEM_H */ |