1 /* internal.h: mm/ internal definitions
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
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.
11 #ifndef __MM_INTERNAL_H
12 #define __MM_INTERNAL_H
16 #include <linux/pagemap.h>
17 #include <linux/tracepoint-defs.h>
20 * The set of flags that only affect watermark checking and reclaim
21 * behaviour. This is used by the MM to obey the caller constraints
22 * about IO, FS and watermark checking while ignoring placement
23 * hints such as HIGHMEM usage.
25 #define GFP_RECLAIM_MASK (__GFP_RECLAIM|__GFP_HIGH|__GFP_IO|__GFP_FS|\
26 __GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\
27 __GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC|\
30 /* The GFP flags allowed during early boot */
31 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_RECLAIM|__GFP_IO|__GFP_FS))
33 /* Control allocation cpuset and node placement constraints */
34 #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
36 /* Do not use these with a slab allocator */
37 #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
39 int do_swap_page(struct fault_env
*fe
, pte_t orig_pte
);
41 void free_pgtables(struct mmu_gather
*tlb
, struct vm_area_struct
*start_vma
,
42 unsigned long floor
, unsigned long ceiling
);
44 void unmap_page_range(struct mmu_gather
*tlb
,
45 struct vm_area_struct
*vma
,
46 unsigned long addr
, unsigned long end
,
47 struct zap_details
*details
);
49 extern int __do_page_cache_readahead(struct address_space
*mapping
,
50 struct file
*filp
, pgoff_t offset
, unsigned long nr_to_read
,
51 unsigned long lookahead_size
);
54 * Submit IO for the read-ahead request in file_ra_state.
56 static inline unsigned long ra_submit(struct file_ra_state
*ra
,
57 struct address_space
*mapping
, struct file
*filp
)
59 return __do_page_cache_readahead(mapping
, filp
,
60 ra
->start
, ra
->size
, ra
->async_size
);
64 * Turn a non-refcounted page (->_refcount == 0) into refcounted with
67 static inline void set_page_refcounted(struct page
*page
)
69 VM_BUG_ON_PAGE(PageTail(page
), page
);
70 VM_BUG_ON_PAGE(page_ref_count(page
), page
);
71 set_page_count(page
, 1);
74 extern unsigned long highest_memmap_pfn
;
79 extern int isolate_lru_page(struct page
*page
);
80 extern void putback_lru_page(struct page
*page
);
81 extern bool pgdat_reclaimable(struct pglist_data
*pgdat
);
86 extern pmd_t
*mm_find_pmd(struct mm_struct
*mm
, unsigned long address
);
93 * Structure for holding the mostly immutable allocation parameters passed
94 * between functions involved in allocations, including the alloc_pages*
95 * family of functions.
97 * nodemask, migratetype and high_zoneidx are initialized only once in
98 * __alloc_pages_nodemask() and then never change.
100 * zonelist, preferred_zone and classzone_idx are set first in
101 * __alloc_pages_nodemask() for the fast path, and might be later changed
102 * in __alloc_pages_slowpath(). All other functions pass the whole strucure
103 * by a const pointer.
105 struct alloc_context
{
106 struct zonelist
*zonelist
;
107 nodemask_t
*nodemask
;
108 struct zoneref
*preferred_zoneref
;
110 enum zone_type high_zoneidx
;
111 bool spread_dirty_pages
;
114 #define ac_classzone_idx(ac) zonelist_zone_idx(ac->preferred_zoneref)
117 * Locate the struct page for both the matching buddy in our
118 * pair (buddy1) and the combined O(n+1) page they form (page).
120 * 1) Any buddy B1 will have an order O twin B2 which satisfies
121 * the following equation:
123 * For example, if the starting buddy (buddy2) is #8 its order
125 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10
127 * 2) Any buddy B will have an order O+1 parent P which
128 * satisfies the following equation:
131 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER
133 static inline unsigned long
134 __find_buddy_index(unsigned long page_idx
, unsigned int order
)
136 return page_idx
^ (1 << order
);
139 extern struct page
*__pageblock_pfn_to_page(unsigned long start_pfn
,
140 unsigned long end_pfn
, struct zone
*zone
);
142 static inline struct page
*pageblock_pfn_to_page(unsigned long start_pfn
,
143 unsigned long end_pfn
, struct zone
*zone
)
145 if (zone
->contiguous
)
146 return pfn_to_page(start_pfn
);
148 return __pageblock_pfn_to_page(start_pfn
, end_pfn
, zone
);
151 extern int __isolate_free_page(struct page
*page
, unsigned int order
);
152 extern void __free_pages_bootmem(struct page
*page
, unsigned long pfn
,
154 extern void prep_compound_page(struct page
*page
, unsigned int order
);
155 extern void post_alloc_hook(struct page
*page
, unsigned int order
,
157 extern int user_min_free_kbytes
;
159 #if defined CONFIG_COMPACTION || defined CONFIG_CMA
165 * compact_control is used to track pages being migrated and the free pages
166 * they are being migrated to during memory compaction. The free_pfn starts
167 * at the end of a zone and migrate_pfn begins at the start. Movable pages
168 * are moved to the end of a zone during a compaction run and the run
169 * completes when free_pfn <= migrate_pfn
171 struct compact_control
{
172 struct list_head freepages
; /* List of free pages to migrate to */
173 struct list_head migratepages
; /* List of pages being migrated */
174 unsigned long nr_freepages
; /* Number of isolated free pages */
175 unsigned long nr_migratepages
; /* Number of pages to migrate */
176 unsigned long free_pfn
; /* isolate_freepages search base */
177 unsigned long migrate_pfn
; /* isolate_migratepages search base */
178 unsigned long last_migrated_pfn
;/* Not yet flushed page being freed */
179 enum migrate_mode mode
; /* Async or sync migration mode */
180 bool ignore_skip_hint
; /* Scan blocks even if marked skip */
181 bool direct_compaction
; /* False from kcompactd or /proc/... */
182 bool whole_zone
; /* Whole zone has been scanned */
183 int order
; /* order a direct compactor needs */
184 const gfp_t gfp_mask
; /* gfp mask of a direct compactor */
185 const unsigned int alloc_flags
; /* alloc flags of a direct compactor */
186 const int classzone_idx
; /* zone index of a direct compactor */
188 bool contended
; /* Signal lock or sched contention */
192 isolate_freepages_range(struct compact_control
*cc
,
193 unsigned long start_pfn
, unsigned long end_pfn
);
195 isolate_migratepages_range(struct compact_control
*cc
,
196 unsigned long low_pfn
, unsigned long end_pfn
);
197 int find_suitable_fallback(struct free_area
*area
, unsigned int order
,
198 int migratetype
, bool only_stealable
, bool *can_steal
);
203 * This function returns the order of a free page in the buddy system. In
204 * general, page_zone(page)->lock must be held by the caller to prevent the
205 * page from being allocated in parallel and returning garbage as the order.
206 * If a caller does not hold page_zone(page)->lock, it must guarantee that the
207 * page cannot be allocated or merged in parallel. Alternatively, it must
208 * handle invalid values gracefully, and use page_order_unsafe() below.
210 static inline unsigned int page_order(struct page
*page
)
212 /* PageBuddy() must be checked by the caller */
213 return page_private(page
);
217 * Like page_order(), but for callers who cannot afford to hold the zone lock.
218 * PageBuddy() should be checked first by the caller to minimize race window,
219 * and invalid values must be handled gracefully.
221 * READ_ONCE is used so that if the caller assigns the result into a local
222 * variable and e.g. tests it for valid range before using, the compiler cannot
223 * decide to remove the variable and inline the page_private(page) multiple
224 * times, potentially observing different values in the tests and the actual
227 #define page_order_unsafe(page) READ_ONCE(page_private(page))
229 static inline bool is_cow_mapping(vm_flags_t flags
)
231 return (flags
& (VM_SHARED
| VM_MAYWRITE
)) == VM_MAYWRITE
;
235 * These three helpers classifies VMAs for virtual memory accounting.
239 * Executable code area - executable, not writable, not stack
241 static inline bool is_exec_mapping(vm_flags_t flags
)
243 return (flags
& (VM_EXEC
| VM_WRITE
| VM_STACK
)) == VM_EXEC
;
247 * Stack area - atomatically grows in one direction
249 * VM_GROWSUP / VM_GROWSDOWN VMAs are always private anonymous:
250 * do_mmap() forbids all other combinations.
252 static inline bool is_stack_mapping(vm_flags_t flags
)
254 return (flags
& VM_STACK
) == VM_STACK
;
258 * Data area - private, writable, not stack
260 static inline bool is_data_mapping(vm_flags_t flags
)
262 return (flags
& (VM_WRITE
| VM_SHARED
| VM_STACK
)) == VM_WRITE
;
266 void __vma_link_list(struct mm_struct
*mm
, struct vm_area_struct
*vma
,
267 struct vm_area_struct
*prev
, struct rb_node
*rb_parent
);
270 extern long populate_vma_page_range(struct vm_area_struct
*vma
,
271 unsigned long start
, unsigned long end
, int *nonblocking
);
272 extern void munlock_vma_pages_range(struct vm_area_struct
*vma
,
273 unsigned long start
, unsigned long end
);
274 static inline void munlock_vma_pages_all(struct vm_area_struct
*vma
)
276 munlock_vma_pages_range(vma
, vma
->vm_start
, vma
->vm_end
);
280 * must be called with vma's mmap_sem held for read or write, and page locked.
282 extern void mlock_vma_page(struct page
*page
);
283 extern unsigned int munlock_vma_page(struct page
*page
);
286 * Clear the page's PageMlocked(). This can be useful in a situation where
287 * we want to unconditionally remove a page from the pagecache -- e.g.,
288 * on truncation or freeing.
290 * It is legal to call this function for any page, mlocked or not.
291 * If called for a page that is still mapped by mlocked vmas, all we do
292 * is revert to lazy LRU behaviour -- semantics are not broken.
294 extern void clear_page_mlock(struct page
*page
);
297 * mlock_migrate_page - called only from migrate_misplaced_transhuge_page()
298 * (because that does not go through the full procedure of migration ptes):
299 * to migrate the Mlocked page flag; update statistics.
301 static inline void mlock_migrate_page(struct page
*newpage
, struct page
*page
)
303 if (TestClearPageMlocked(page
)) {
304 int nr_pages
= hpage_nr_pages(page
);
306 /* Holding pmd lock, no change in irq context: __mod is safe */
307 __mod_zone_page_state(page_zone(page
), NR_MLOCK
, -nr_pages
);
308 SetPageMlocked(newpage
);
309 __mod_zone_page_state(page_zone(newpage
), NR_MLOCK
, nr_pages
);
313 extern pmd_t
maybe_pmd_mkwrite(pmd_t pmd
, struct vm_area_struct
*vma
);
316 * At what user virtual address is page expected in @vma?
318 static inline unsigned long
319 __vma_address(struct page
*page
, struct vm_area_struct
*vma
)
321 pgoff_t pgoff
= page_to_pgoff(page
);
322 return vma
->vm_start
+ ((pgoff
- vma
->vm_pgoff
) << PAGE_SHIFT
);
325 static inline unsigned long
326 vma_address(struct page
*page
, struct vm_area_struct
*vma
)
328 unsigned long address
= __vma_address(page
, vma
);
330 /* page should be within @vma mapping range */
331 VM_BUG_ON_VMA(address
< vma
->vm_start
|| address
>= vma
->vm_end
, vma
);
336 #else /* !CONFIG_MMU */
337 static inline void clear_page_mlock(struct page
*page
) { }
338 static inline void mlock_vma_page(struct page
*page
) { }
339 static inline void mlock_migrate_page(struct page
*new, struct page
*old
) { }
341 #endif /* !CONFIG_MMU */
344 * Return the mem_map entry representing the 'offset' subpage within
345 * the maximally aligned gigantic page 'base'. Handle any discontiguity
346 * in the mem_map at MAX_ORDER_NR_PAGES boundaries.
348 static inline struct page
*mem_map_offset(struct page
*base
, int offset
)
350 if (unlikely(offset
>= MAX_ORDER_NR_PAGES
))
351 return nth_page(base
, offset
);
352 return base
+ offset
;
356 * Iterator over all subpages within the maximally aligned gigantic
357 * page 'base'. Handle any discontiguity in the mem_map.
359 static inline struct page
*mem_map_next(struct page
*iter
,
360 struct page
*base
, int offset
)
362 if (unlikely((offset
& (MAX_ORDER_NR_PAGES
- 1)) == 0)) {
363 unsigned long pfn
= page_to_pfn(base
) + offset
;
366 return pfn_to_page(pfn
);
372 * FLATMEM and DISCONTIGMEM configurations use alloc_bootmem_node,
373 * so all functions starting at paging_init should be marked __init
374 * in those cases. SPARSEMEM, however, allows for memory hotplug,
375 * and alloc_bootmem_node is not used.
377 #ifdef CONFIG_SPARSEMEM
378 #define __paginginit __meminit
380 #define __paginginit __init
383 /* Memory initialisation debug and verification */
390 #ifdef CONFIG_DEBUG_MEMORY_INIT
392 extern int mminit_loglevel
;
394 #define mminit_dprintk(level, prefix, fmt, arg...) \
396 if (level < mminit_loglevel) { \
397 if (level <= MMINIT_WARNING) \
398 pr_warn("mminit::" prefix " " fmt, ##arg); \
400 printk(KERN_DEBUG "mminit::" prefix " " fmt, ##arg); \
404 extern void mminit_verify_pageflags_layout(void);
405 extern void mminit_verify_zonelist(void);
408 static inline void mminit_dprintk(enum mminit_level level
,
409 const char *prefix
, const char *fmt
, ...)
413 static inline void mminit_verify_pageflags_layout(void)
417 static inline void mminit_verify_zonelist(void)
420 #endif /* CONFIG_DEBUG_MEMORY_INIT */
422 /* mminit_validate_memmodel_limits is independent of CONFIG_DEBUG_MEMORY_INIT */
423 #if defined(CONFIG_SPARSEMEM)
424 extern void mminit_validate_memmodel_limits(unsigned long *start_pfn
,
425 unsigned long *end_pfn
);
427 static inline void mminit_validate_memmodel_limits(unsigned long *start_pfn
,
428 unsigned long *end_pfn
)
431 #endif /* CONFIG_SPARSEMEM */
433 #define NODE_RECLAIM_NOSCAN -2
434 #define NODE_RECLAIM_FULL -1
435 #define NODE_RECLAIM_SOME 0
436 #define NODE_RECLAIM_SUCCESS 1
438 extern int hwpoison_filter(struct page
*p
);
440 extern u32 hwpoison_filter_dev_major
;
441 extern u32 hwpoison_filter_dev_minor
;
442 extern u64 hwpoison_filter_flags_mask
;
443 extern u64 hwpoison_filter_flags_value
;
444 extern u64 hwpoison_filter_memcg
;
445 extern u32 hwpoison_filter_enable
;
447 extern unsigned long __must_check
vm_mmap_pgoff(struct file
*, unsigned long,
448 unsigned long, unsigned long,
449 unsigned long, unsigned long);
451 extern void set_pageblock_order(void);
452 unsigned long reclaim_clean_pages_from_list(struct zone
*zone
,
453 struct list_head
*page_list
);
454 /* The ALLOC_WMARK bits are used as an index to zone->watermark */
455 #define ALLOC_WMARK_MIN WMARK_MIN
456 #define ALLOC_WMARK_LOW WMARK_LOW
457 #define ALLOC_WMARK_HIGH WMARK_HIGH
458 #define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
460 /* Mask to get the watermark bits */
461 #define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
463 #define ALLOC_HARDER 0x10 /* try to alloc harder */
464 #define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
465 #define ALLOC_CPUSET 0x40 /* check for correct cpuset */
466 #define ALLOC_CMA 0x80 /* allow allocations from CMA areas */
469 struct tlbflush_unmap_batch
;
471 #ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
472 void try_to_unmap_flush(void);
473 void try_to_unmap_flush_dirty(void);
475 static inline void try_to_unmap_flush(void)
478 static inline void try_to_unmap_flush_dirty(void)
482 #endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
484 extern const struct trace_print_flags pageflag_names
[];
485 extern const struct trace_print_flags vmaflag_names
[];
486 extern const struct trace_print_flags gfpflag_names
[];
488 #endif /* __MM_INTERNAL_H */