1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _LINUX_HIGHMEM_INTERNAL_H 3 #define _LINUX_HIGHMEM_INTERNAL_H 4 5 /* 6 * Outside of CONFIG_HIGHMEM to support X86 32bit iomap_atomic() cruft. 7 */ 8 #ifdef CONFIG_KMAP_LOCAL 9 void *__kmap_local_pfn_prot(unsigned long pfn, pgprot_t prot); 10 void *__kmap_local_page_prot(struct page *page, pgprot_t prot); 11 void kunmap_local_indexed(void *vaddr); 12 void kmap_local_fork(struct task_struct *tsk); 13 void __kmap_local_sched_out(void); 14 void __kmap_local_sched_in(void); 15 static inline void kmap_assert_nomap(void) 16 { 17 DEBUG_LOCKS_WARN_ON(current->kmap_ctrl.idx); 18 } 19 #else 20 static inline void kmap_local_fork(struct task_struct *tsk) { } 21 static inline void kmap_assert_nomap(void) { } 22 #endif 23 24 #ifdef CONFIG_HIGHMEM 25 #include <asm/highmem.h> 26 27 #ifndef ARCH_HAS_KMAP_FLUSH_TLB 28 static inline void kmap_flush_tlb(unsigned long addr) { } 29 #endif 30 31 #ifndef kmap_prot 32 #define kmap_prot PAGE_KERNEL 33 #endif 34 35 void *kmap_high(struct page *page); 36 void kunmap_high(struct page *page); 37 void __kmap_flush_unused(void); 38 struct page *__kmap_to_page(void *addr); 39 40 static inline void *kmap(struct page *page) 41 { 42 void *addr; 43 44 might_sleep(); 45 if (!PageHighMem(page)) 46 addr = page_address(page); 47 else 48 addr = kmap_high(page); 49 kmap_flush_tlb((unsigned long)addr); 50 return addr; 51 } 52 53 static inline void kunmap(struct page *page) 54 { 55 might_sleep(); 56 if (!PageHighMem(page)) 57 return; 58 kunmap_high(page); 59 } 60 61 static inline struct page *kmap_to_page(void *addr) 62 { 63 return __kmap_to_page(addr); 64 } 65 66 static inline void kmap_flush_unused(void) 67 { 68 __kmap_flush_unused(); 69 } 70 71 static inline void *kmap_local_page(struct page *page) 72 { 73 return __kmap_local_page_prot(page, kmap_prot); 74 } 75 76 static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot) 77 { 78 return __kmap_local_page_prot(page, prot); 79 } 80 81 static inline void *kmap_local_pfn(unsigned long pfn) 82 { 83 return __kmap_local_pfn_prot(pfn, kmap_prot); 84 } 85 86 static inline void __kunmap_local(void *vaddr) 87 { 88 kunmap_local_indexed(vaddr); 89 } 90 91 static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot) 92 { 93 preempt_disable(); 94 pagefault_disable(); 95 return __kmap_local_page_prot(page, prot); 96 } 97 98 static inline void *kmap_atomic(struct page *page) 99 { 100 return kmap_atomic_prot(page, kmap_prot); 101 } 102 103 static inline void *kmap_atomic_pfn(unsigned long pfn) 104 { 105 preempt_disable(); 106 pagefault_disable(); 107 return __kmap_local_pfn_prot(pfn, kmap_prot); 108 } 109 110 static inline void __kunmap_atomic(void *addr) 111 { 112 kunmap_local_indexed(addr); 113 pagefault_enable(); 114 preempt_enable(); 115 } 116 117 unsigned int __nr_free_highpages(void); 118 extern atomic_long_t _totalhigh_pages; 119 120 static inline unsigned int nr_free_highpages(void) 121 { 122 return __nr_free_highpages(); 123 } 124 125 static inline unsigned long totalhigh_pages(void) 126 { 127 return (unsigned long)atomic_long_read(&_totalhigh_pages); 128 } 129 130 static inline void totalhigh_pages_add(long count) 131 { 132 atomic_long_add(count, &_totalhigh_pages); 133 } 134 135 #else /* CONFIG_HIGHMEM */ 136 137 static inline struct page *kmap_to_page(void *addr) 138 { 139 return virt_to_page(addr); 140 } 141 142 static inline void *kmap(struct page *page) 143 { 144 might_sleep(); 145 return page_address(page); 146 } 147 148 static inline void kunmap_high(struct page *page) { } 149 static inline void kmap_flush_unused(void) { } 150 151 static inline void kunmap(struct page *page) 152 { 153 #ifdef ARCH_HAS_FLUSH_ON_KUNMAP 154 kunmap_flush_on_unmap(page_address(page)); 155 #endif 156 } 157 158 static inline void *kmap_local_page(struct page *page) 159 { 160 return page_address(page); 161 } 162 163 static inline void *kmap_local_page_prot(struct page *page, pgprot_t prot) 164 { 165 return kmap_local_page(page); 166 } 167 168 static inline void *kmap_local_pfn(unsigned long pfn) 169 { 170 return kmap_local_page(pfn_to_page(pfn)); 171 } 172 173 static inline void __kunmap_local(void *addr) 174 { 175 #ifdef ARCH_HAS_FLUSH_ON_KUNMAP 176 kunmap_flush_on_unmap(addr); 177 #endif 178 } 179 180 static inline void *kmap_atomic(struct page *page) 181 { 182 preempt_disable(); 183 pagefault_disable(); 184 return page_address(page); 185 } 186 187 static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot) 188 { 189 return kmap_atomic(page); 190 } 191 192 static inline void *kmap_atomic_pfn(unsigned long pfn) 193 { 194 return kmap_atomic(pfn_to_page(pfn)); 195 } 196 197 static inline void __kunmap_atomic(void *addr) 198 { 199 #ifdef ARCH_HAS_FLUSH_ON_KUNMAP 200 kunmap_flush_on_unmap(addr); 201 #endif 202 pagefault_enable(); 203 preempt_enable(); 204 } 205 206 static inline unsigned int nr_free_highpages(void) { return 0; } 207 static inline unsigned long totalhigh_pages(void) { return 0UL; } 208 209 #endif /* CONFIG_HIGHMEM */ 210 211 /* 212 * Prevent people trying to call kunmap_atomic() as if it were kunmap() 213 * kunmap_atomic() should get the return value of kmap_atomic, not the page. 214 */ 215 #define kunmap_atomic(__addr) \ 216 do { \ 217 BUILD_BUG_ON(__same_type((__addr), struct page *)); \ 218 __kunmap_atomic(__addr); \ 219 } while (0) 220 221 #define kunmap_local(__addr) \ 222 do { \ 223 BUILD_BUG_ON(__same_type((__addr), struct page *)); \ 224 __kunmap_local(__addr); \ 225 } while (0) 226 227 #endif 228