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 static inline void set_page_count(struct page *page, int v) 20 { 21 atomic_set(&page->_count, v); 22 } 23 24 /* 25 * Turn a non-refcounted page (->_count == 0) into refcounted with 26 * a count of one. 27 */ 28 static inline void set_page_refcounted(struct page *page) 29 { 30 VM_BUG_ON(PageTail(page)); 31 VM_BUG_ON(atomic_read(&page->_count)); 32 set_page_count(page, 1); 33 } 34 35 static inline void __put_page(struct page *page) 36 { 37 atomic_dec(&page->_count); 38 } 39 40 extern unsigned long highest_memmap_pfn; 41 42 /* 43 * in mm/vmscan.c: 44 */ 45 extern int isolate_lru_page(struct page *page); 46 extern void putback_lru_page(struct page *page); 47 48 /* 49 * in mm/page_alloc.c 50 */ 51 extern void __free_pages_bootmem(struct page *page, unsigned int order); 52 extern void prep_compound_page(struct page *page, unsigned long order); 53 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 /* 78 * unevictable_migrate_page() called only from migrate_page_copy() to 79 * migrate unevictable flag to new page. 80 * Note that the old page has been isolated from the LRU lists at this 81 * point so we don't need to worry about LRU statistics. 82 */ 83 static inline void unevictable_migrate_page(struct page *new, struct page *old) 84 { 85 if (TestClearPageUnevictable(old)) 86 SetPageUnevictable(new); 87 } 88 89 #ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT 90 /* 91 * Called only in fault path via page_evictable() for a new page 92 * to determine if it's being mapped into a LOCKED vma. 93 * If so, mark page as mlocked. 94 */ 95 static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page) 96 { 97 VM_BUG_ON(PageLRU(page)); 98 99 if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) 100 return 0; 101 102 if (!TestSetPageMlocked(page)) { 103 inc_zone_page_state(page, NR_MLOCK); 104 count_vm_event(UNEVICTABLE_PGMLOCKED); 105 } 106 return 1; 107 } 108 109 /* 110 * must be called with vma's mmap_sem held for read, and page locked. 111 */ 112 extern void mlock_vma_page(struct page *page); 113 114 /* 115 * Clear the page's PageMlocked(). This can be useful in a situation where 116 * we want to unconditionally remove a page from the pagecache -- e.g., 117 * on truncation or freeing. 118 * 119 * It is legal to call this function for any page, mlocked or not. 120 * If called for a page that is still mapped by mlocked vmas, all we do 121 * is revert to lazy LRU behaviour -- semantics are not broken. 122 */ 123 extern void __clear_page_mlock(struct page *page); 124 static inline void clear_page_mlock(struct page *page) 125 { 126 if (unlikely(TestClearPageMlocked(page))) 127 __clear_page_mlock(page); 128 } 129 130 /* 131 * mlock_migrate_page - called only from migrate_page_copy() to 132 * migrate the Mlocked page flag; update statistics. 133 */ 134 static inline void mlock_migrate_page(struct page *newpage, struct page *page) 135 { 136 if (TestClearPageMlocked(page)) { 137 unsigned long flags; 138 139 local_irq_save(flags); 140 __dec_zone_page_state(page, NR_MLOCK); 141 SetPageMlocked(newpage); 142 __inc_zone_page_state(newpage, NR_MLOCK); 143 local_irq_restore(flags); 144 } 145 } 146 147 #else /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ 148 static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p) 149 { 150 return 0; 151 } 152 static inline void clear_page_mlock(struct page *page) { } 153 static inline void mlock_vma_page(struct page *page) { } 154 static inline void mlock_migrate_page(struct page *new, struct page *old) { } 155 156 #endif /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ 157 158 /* 159 * Return the mem_map entry representing the 'offset' subpage within 160 * the maximally aligned gigantic page 'base'. Handle any discontiguity 161 * in the mem_map at MAX_ORDER_NR_PAGES boundaries. 162 */ 163 static inline struct page *mem_map_offset(struct page *base, int offset) 164 { 165 if (unlikely(offset >= MAX_ORDER_NR_PAGES)) 166 return pfn_to_page(page_to_pfn(base) + offset); 167 return base + offset; 168 } 169 170 /* 171 * Iterator over all subpages withing the maximally aligned gigantic 172 * page 'base'. Handle any discontiguity in the mem_map. 173 */ 174 static inline struct page *mem_map_next(struct page *iter, 175 struct page *base, int offset) 176 { 177 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) { 178 unsigned long pfn = page_to_pfn(base) + offset; 179 if (!pfn_valid(pfn)) 180 return NULL; 181 return pfn_to_page(pfn); 182 } 183 return iter + 1; 184 } 185 186 /* 187 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node, 188 * so all functions starting at paging_init should be marked __init 189 * in those cases. SPARSEMEM, however, allows for memory hotplug, 190 * and alloc_bootmem_node is not used. 191 */ 192 #ifdef CONFIG_SPARSEMEM 193 #define __paginginit __meminit 194 #else 195 #define __paginginit __init 196 #endif 197 198 /* Memory initialisation debug and verification */ 199 enum mminit_level { 200 MMINIT_WARNING, 201 MMINIT_VERIFY, 202 MMINIT_TRACE 203 }; 204 205 #ifdef CONFIG_DEBUG_MEMORY_INIT 206 207 extern int mminit_loglevel; 208 209 #define mminit_dprintk(level, prefix, fmt, arg...) \ 210 do { \ 211 if (level < mminit_loglevel) { \ 212 printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \ 213 printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \ 214 } \ 215 } while (0) 216 217 extern void mminit_verify_pageflags_layout(void); 218 extern void mminit_verify_page_links(struct page *page, 219 enum zone_type zone, unsigned long nid, unsigned long pfn); 220 extern void mminit_verify_zonelist(void); 221 222 #else 223 224 static inline void mminit_dprintk(enum mminit_level level, 225 const char *prefix, const char *fmt, ...) 226 { 227 } 228 229 static inline void mminit_verify_pageflags_layout(void) 230 { 231 } 232 233 static inline void mminit_verify_page_links(struct page *page, 234 enum zone_type zone, unsigned long nid, unsigned long pfn) 235 { 236 } 237 238 static inline void mminit_verify_zonelist(void) 239 { 240 } 241 #endif /* CONFIG_DEBUG_MEMORY_INIT */ 242 243 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */ 244 #if defined(CONFIG_SPARSEMEM) 245 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn, 246 unsigned long *end_pfn); 247 #else 248 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn, 249 unsigned long *end_pfn) 250 { 251 } 252 #endif /* CONFIG_SPARSEMEM */ 253 254 int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 255 unsigned long start, int len, unsigned int foll_flags, 256 struct page **pages, struct vm_area_struct **vmas); 257 258 #define ZONE_RECLAIM_NOSCAN -2 259 #define ZONE_RECLAIM_FULL -1 260 #define ZONE_RECLAIM_SOME 0 261 #define ZONE_RECLAIM_SUCCESS 1 262 #endif 263