1 /* internal.h: mm/ internal definitions 2 * 3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. 4 * Written by David Howells (dhowells@redhat.com) 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 #ifndef __MM_INTERNAL_H 12 #define __MM_INTERNAL_H 13 14 #include <linux/mm.h> 15 16 void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma, 17 unsigned long floor, unsigned long ceiling); 18 19 extern void prep_compound_page(struct page *page, unsigned long order); 20 extern void prep_compound_gigantic_page(struct page *page, unsigned long order); 21 22 static inline void set_page_count(struct page *page, int v) 23 { 24 atomic_set(&page->_count, v); 25 } 26 27 /* 28 * Turn a non-refcounted page (->_count == 0) into refcounted with 29 * a count of one. 30 */ 31 static inline void set_page_refcounted(struct page *page) 32 { 33 VM_BUG_ON(PageTail(page)); 34 VM_BUG_ON(atomic_read(&page->_count)); 35 set_page_count(page, 1); 36 } 37 38 static inline void __put_page(struct page *page) 39 { 40 atomic_dec(&page->_count); 41 } 42 43 /* 44 * in mm/vmscan.c: 45 */ 46 extern int isolate_lru_page(struct page *page); 47 extern void putback_lru_page(struct page *page); 48 49 /* 50 * in mm/page_alloc.c 51 */ 52 extern unsigned long highest_memmap_pfn; 53 extern void __free_pages_bootmem(struct page *page, unsigned int order); 54 55 /* 56 * function for dealing with page's order in buddy system. 57 * zone->lock is already acquired when we use these. 58 * So, we don't need atomic page->flags operations here. 59 */ 60 static inline unsigned long page_order(struct page *page) 61 { 62 VM_BUG_ON(!PageBuddy(page)); 63 return page_private(page); 64 } 65 66 #ifdef CONFIG_HAVE_MLOCK 67 extern long mlock_vma_pages_range(struct vm_area_struct *vma, 68 unsigned long start, unsigned long end); 69 extern void munlock_vma_pages_range(struct vm_area_struct *vma, 70 unsigned long start, unsigned long end); 71 static inline void munlock_vma_pages_all(struct vm_area_struct *vma) 72 { 73 munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end); 74 } 75 #endif 76 77 #ifdef CONFIG_UNEVICTABLE_LRU 78 /* 79 * unevictable_migrate_page() called only from migrate_page_copy() to 80 * migrate unevictable flag to new page. 81 * Note that the old page has been isolated from the LRU lists at this 82 * point so we don't need to worry about LRU statistics. 83 */ 84 static inline void unevictable_migrate_page(struct page *new, struct page *old) 85 { 86 if (TestClearPageUnevictable(old)) 87 SetPageUnevictable(new); 88 } 89 #else 90 static inline void unevictable_migrate_page(struct page *new, struct page *old) 91 { 92 } 93 #endif 94 95 #ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT 96 /* 97 * Called only in fault path via page_evictable() for a new page 98 * to determine if it's being mapped into a LOCKED vma. 99 * If so, mark page as mlocked. 100 */ 101 static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page) 102 { 103 VM_BUG_ON(PageLRU(page)); 104 105 if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) 106 return 0; 107 108 if (!TestSetPageMlocked(page)) { 109 inc_zone_page_state(page, NR_MLOCK); 110 count_vm_event(UNEVICTABLE_PGMLOCKED); 111 } 112 return 1; 113 } 114 115 /* 116 * must be called with vma's mmap_sem held for read, and page locked. 117 */ 118 extern void mlock_vma_page(struct page *page); 119 120 /* 121 * Clear the page's PageMlocked(). This can be useful in a situation where 122 * we want to unconditionally remove a page from the pagecache -- e.g., 123 * on truncation or freeing. 124 * 125 * It is legal to call this function for any page, mlocked or not. 126 * If called for a page that is still mapped by mlocked vmas, all we do 127 * is revert to lazy LRU behaviour -- semantics are not broken. 128 */ 129 extern void __clear_page_mlock(struct page *page); 130 static inline void clear_page_mlock(struct page *page) 131 { 132 if (unlikely(TestClearPageMlocked(page))) 133 __clear_page_mlock(page); 134 } 135 136 /* 137 * mlock_migrate_page - called only from migrate_page_copy() to 138 * migrate the Mlocked page flag; update statistics. 139 */ 140 static inline void mlock_migrate_page(struct page *newpage, struct page *page) 141 { 142 if (TestClearPageMlocked(page)) { 143 unsigned long flags; 144 145 local_irq_save(flags); 146 __dec_zone_page_state(page, NR_MLOCK); 147 SetPageMlocked(newpage); 148 __inc_zone_page_state(newpage, NR_MLOCK); 149 local_irq_restore(flags); 150 } 151 } 152 153 /* 154 * free_page_mlock() -- clean up attempts to free and mlocked() page. 155 * Page should not be on lru, so no need to fix that up. 156 * free_pages_check() will verify... 157 */ 158 static inline void free_page_mlock(struct page *page) 159 { 160 if (unlikely(TestClearPageMlocked(page))) { 161 unsigned long flags; 162 163 local_irq_save(flags); 164 __dec_zone_page_state(page, NR_MLOCK); 165 __count_vm_event(UNEVICTABLE_MLOCKFREED); 166 local_irq_restore(flags); 167 } 168 } 169 170 #else /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ 171 static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p) 172 { 173 return 0; 174 } 175 static inline void clear_page_mlock(struct page *page) { } 176 static inline void mlock_vma_page(struct page *page) { } 177 static inline void mlock_migrate_page(struct page *new, struct page *old) { } 178 static inline void free_page_mlock(struct page *page) { } 179 180 #endif /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ 181 182 /* 183 * Return the mem_map entry representing the 'offset' subpage within 184 * the maximally aligned gigantic page 'base'. Handle any discontiguity 185 * in the mem_map at MAX_ORDER_NR_PAGES boundaries. 186 */ 187 static inline struct page *mem_map_offset(struct page *base, int offset) 188 { 189 if (unlikely(offset >= MAX_ORDER_NR_PAGES)) 190 return pfn_to_page(page_to_pfn(base) + offset); 191 return base + offset; 192 } 193 194 /* 195 * Iterator over all subpages withing the maximally aligned gigantic 196 * page 'base'. Handle any discontiguity in the mem_map. 197 */ 198 static inline struct page *mem_map_next(struct page *iter, 199 struct page *base, int offset) 200 { 201 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) { 202 unsigned long pfn = page_to_pfn(base) + offset; 203 if (!pfn_valid(pfn)) 204 return NULL; 205 return pfn_to_page(pfn); 206 } 207 return iter + 1; 208 } 209 210 /* 211 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node, 212 * so all functions starting at paging_init should be marked __init 213 * in those cases. SPARSEMEM, however, allows for memory hotplug, 214 * and alloc_bootmem_node is not used. 215 */ 216 #ifdef CONFIG_SPARSEMEM 217 #define __paginginit __meminit 218 #else 219 #define __paginginit __init 220 #endif 221 222 /* Memory initialisation debug and verification */ 223 enum mminit_level { 224 MMINIT_WARNING, 225 MMINIT_VERIFY, 226 MMINIT_TRACE 227 }; 228 229 #ifdef CONFIG_DEBUG_MEMORY_INIT 230 231 extern int mminit_loglevel; 232 233 #define mminit_dprintk(level, prefix, fmt, arg...) \ 234 do { \ 235 if (level < mminit_loglevel) { \ 236 printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \ 237 printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \ 238 } \ 239 } while (0) 240 241 extern void mminit_verify_pageflags_layout(void); 242 extern void mminit_verify_page_links(struct page *page, 243 enum zone_type zone, unsigned long nid, unsigned long pfn); 244 extern void mminit_verify_zonelist(void); 245 246 #else 247 248 static inline void mminit_dprintk(enum mminit_level level, 249 const char *prefix, const char *fmt, ...) 250 { 251 } 252 253 static inline void mminit_verify_pageflags_layout(void) 254 { 255 } 256 257 static inline void mminit_verify_page_links(struct page *page, 258 enum zone_type zone, unsigned long nid, unsigned long pfn) 259 { 260 } 261 262 static inline void mminit_verify_zonelist(void) 263 { 264 } 265 #endif /* CONFIG_DEBUG_MEMORY_INIT */ 266 267 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */ 268 #if defined(CONFIG_SPARSEMEM) 269 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn, 270 unsigned long *end_pfn); 271 #else 272 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn, 273 unsigned long *end_pfn) 274 { 275 } 276 #endif /* CONFIG_SPARSEMEM */ 277 278 #define GUP_FLAGS_WRITE 0x1 279 #define GUP_FLAGS_FORCE 0x2 280 #define GUP_FLAGS_IGNORE_VMA_PERMISSIONS 0x4 281 #define GUP_FLAGS_IGNORE_SIGKILL 0x8 282 283 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 284 unsigned long start, int len, int flags, 285 struct page **pages, struct vm_area_struct **vmas); 286 287 #endif 288