internal.h revision 8e4b9a60718970bbc02dfd3abd0b956ab65af231
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 16void free_pgtables(struct mmu_gather *tlb, struct vm_area_struct *start_vma, 17 unsigned long floor, unsigned long ceiling); 18 19static 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 */ 28static 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 35static inline void __put_page(struct page *page) 36{ 37 atomic_dec(&page->_count); 38} 39 40/* 41 * in mm/vmscan.c: 42 */ 43extern int isolate_lru_page(struct page *page); 44extern void putback_lru_page(struct page *page); 45 46/* 47 * in mm/page_alloc.c 48 */ 49extern unsigned long highest_memmap_pfn; 50extern void __free_pages_bootmem(struct page *page, unsigned int order); 51extern void prep_compound_page(struct page *page, unsigned long order); 52 53 54/* 55 * function for dealing with page's order in buddy system. 56 * zone->lock is already acquired when we use these. 57 * So, we don't need atomic page->flags operations here. 58 */ 59static inline unsigned long page_order(struct page *page) 60{ 61 VM_BUG_ON(!PageBuddy(page)); 62 return page_private(page); 63} 64 65#ifdef CONFIG_HAVE_MLOCK 66extern long mlock_vma_pages_range(struct vm_area_struct *vma, 67 unsigned long start, unsigned long end); 68extern void munlock_vma_pages_range(struct vm_area_struct *vma, 69 unsigned long start, unsigned long end); 70static inline void munlock_vma_pages_all(struct vm_area_struct *vma) 71{ 72 munlock_vma_pages_range(vma, vma->vm_start, vma->vm_end); 73} 74#endif 75 76/* 77 * unevictable_migrate_page() called only from migrate_page_copy() to 78 * migrate unevictable flag to new page. 79 * Note that the old page has been isolated from the LRU lists at this 80 * point so we don't need to worry about LRU statistics. 81 */ 82static inline void unevictable_migrate_page(struct page *new, struct page *old) 83{ 84 if (TestClearPageUnevictable(old)) 85 SetPageUnevictable(new); 86} 87 88#ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT 89/* 90 * Called only in fault path via page_evictable() for a new page 91 * to determine if it's being mapped into a LOCKED vma. 92 * If so, mark page as mlocked. 93 */ 94static inline int is_mlocked_vma(struct vm_area_struct *vma, struct page *page) 95{ 96 VM_BUG_ON(PageLRU(page)); 97 98 if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) 99 return 0; 100 101 if (!TestSetPageMlocked(page)) { 102 inc_zone_page_state(page, NR_MLOCK); 103 count_vm_event(UNEVICTABLE_PGMLOCKED); 104 } 105 return 1; 106} 107 108/* 109 * must be called with vma's mmap_sem held for read, and page locked. 110 */ 111extern void mlock_vma_page(struct page *page); 112 113/* 114 * Clear the page's PageMlocked(). This can be useful in a situation where 115 * we want to unconditionally remove a page from the pagecache -- e.g., 116 * on truncation or freeing. 117 * 118 * It is legal to call this function for any page, mlocked or not. 119 * If called for a page that is still mapped by mlocked vmas, all we do 120 * is revert to lazy LRU behaviour -- semantics are not broken. 121 */ 122extern void __clear_page_mlock(struct page *page); 123static inline void clear_page_mlock(struct page *page) 124{ 125 if (unlikely(TestClearPageMlocked(page))) 126 __clear_page_mlock(page); 127} 128 129/* 130 * mlock_migrate_page - called only from migrate_page_copy() to 131 * migrate the Mlocked page flag; update statistics. 132 */ 133static inline void mlock_migrate_page(struct page *newpage, struct page *page) 134{ 135 if (TestClearPageMlocked(page)) { 136 unsigned long flags; 137 138 local_irq_save(flags); 139 __dec_zone_page_state(page, NR_MLOCK); 140 SetPageMlocked(newpage); 141 __inc_zone_page_state(newpage, NR_MLOCK); 142 local_irq_restore(flags); 143 } 144} 145 146#else /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ 147static inline int is_mlocked_vma(struct vm_area_struct *v, struct page *p) 148{ 149 return 0; 150} 151static inline void clear_page_mlock(struct page *page) { } 152static inline void mlock_vma_page(struct page *page) { } 153static inline void mlock_migrate_page(struct page *new, struct page *old) { } 154 155#endif /* CONFIG_HAVE_MLOCKED_PAGE_BIT */ 156 157/* 158 * Return the mem_map entry representing the 'offset' subpage within 159 * the maximally aligned gigantic page 'base'. Handle any discontiguity 160 * in the mem_map at MAX_ORDER_NR_PAGES boundaries. 161 */ 162static inline struct page *mem_map_offset(struct page *base, int offset) 163{ 164 if (unlikely(offset >= MAX_ORDER_NR_PAGES)) 165 return pfn_to_page(page_to_pfn(base) + offset); 166 return base + offset; 167} 168 169/* 170 * Iterator over all subpages withing the maximally aligned gigantic 171 * page 'base'. Handle any discontiguity in the mem_map. 172 */ 173static inline struct page *mem_map_next(struct page *iter, 174 struct page *base, int offset) 175{ 176 if (unlikely((offset & (MAX_ORDER_NR_PAGES - 1)) == 0)) { 177 unsigned long pfn = page_to_pfn(base) + offset; 178 if (!pfn_valid(pfn)) 179 return NULL; 180 return pfn_to_page(pfn); 181 } 182 return iter + 1; 183} 184 185/* 186 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node, 187 * so all functions starting at paging_init should be marked __init 188 * in those cases. SPARSEMEM, however, allows for memory hotplug, 189 * and alloc_bootmem_node is not used. 190 */ 191#ifdef CONFIG_SPARSEMEM 192#define __paginginit __meminit 193#else 194#define __paginginit __init 195#endif 196 197/* Memory initialisation debug and verification */ 198enum mminit_level { 199 MMINIT_WARNING, 200 MMINIT_VERIFY, 201 MMINIT_TRACE 202}; 203 204#ifdef CONFIG_DEBUG_MEMORY_INIT 205 206extern int mminit_loglevel; 207 208#define mminit_dprintk(level, prefix, fmt, arg...) \ 209do { \ 210 if (level < mminit_loglevel) { \ 211 printk(level <= MMINIT_WARNING ? KERN_WARNING : KERN_DEBUG); \ 212 printk(KERN_CONT "mminit::" prefix " " fmt, ##arg); \ 213 } \ 214} while (0) 215 216extern void mminit_verify_pageflags_layout(void); 217extern void mminit_verify_page_links(struct page *page, 218 enum zone_type zone, unsigned long nid, unsigned long pfn); 219extern void mminit_verify_zonelist(void); 220 221#else 222 223static inline void mminit_dprintk(enum mminit_level level, 224 const char *prefix, const char *fmt, ...) 225{ 226} 227 228static inline void mminit_verify_pageflags_layout(void) 229{ 230} 231 232static inline void mminit_verify_page_links(struct page *page, 233 enum zone_type zone, unsigned long nid, unsigned long pfn) 234{ 235} 236 237static inline void mminit_verify_zonelist(void) 238{ 239} 240#endif /* CONFIG_DEBUG_MEMORY_INIT */ 241 242/* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */ 243#if defined(CONFIG_SPARSEMEM) 244extern void mminit_validate_memmodel_limits(unsigned long *start_pfn, 245 unsigned long *end_pfn); 246#else 247static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn, 248 unsigned long *end_pfn) 249{ 250} 251#endif /* CONFIG_SPARSEMEM */ 252 253#define GUP_FLAGS_WRITE 0x01 254#define GUP_FLAGS_FORCE 0x02 255#define GUP_FLAGS_DUMP 0x04 256 257int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, 258 unsigned long start, int len, int flags, 259 struct page **pages, struct vm_area_struct **vmas); 260 261#define ZONE_RECLAIM_NOSCAN -2 262#define ZONE_RECLAIM_FULL -1 263#define ZONE_RECLAIM_SOME 0 264#define ZONE_RECLAIM_SUCCESS 1 265#endif 266