4 #include <linux/mmdebug.h>
5 #include <linux/mmzone.h>
6 #include <linux/stddef.h>
7 #include <linux/linkage.h>
8 #include <linux/topology.h>
10 struct vm_area_struct;
12 /* Plain integer GFP bitmasks. Do not use this directly. */
13 #define ___GFP_DMA 0x01u
14 #define ___GFP_HIGHMEM 0x02u
15 #define ___GFP_DMA32 0x04u
16 #define ___GFP_MOVABLE 0x08u
17 #define ___GFP_RECLAIMABLE 0x10u
18 #define ___GFP_HIGH 0x20u
19 #define ___GFP_IO 0x40u
20 #define ___GFP_FS 0x80u
21 #define ___GFP_COLD 0x100u
22 #define ___GFP_NOWARN 0x200u
23 #define ___GFP_REPEAT 0x400u
24 #define ___GFP_NOFAIL 0x800u
25 #define ___GFP_NORETRY 0x1000u
26 #define ___GFP_MEMALLOC 0x2000u
27 #define ___GFP_COMP 0x4000u
28 #define ___GFP_ZERO 0x8000u
29 #define ___GFP_NOMEMALLOC 0x10000u
30 #define ___GFP_HARDWALL 0x20000u
31 #define ___GFP_THISNODE 0x40000u
32 #define ___GFP_ATOMIC 0x80000u
33 #define ___GFP_NOACCOUNT 0x100000u
34 #define ___GFP_NOTRACK 0x200000u
35 #define ___GFP_DIRECT_RECLAIM 0x400000u
36 #define ___GFP_OTHER_NODE 0x800000u
37 #define ___GFP_WRITE 0x1000000u
38 #define ___GFP_KSWAPD_RECLAIM 0x2000000u
39 /* If the above are modified, __GFP_BITS_SHIFT may need updating */
42 * Physical address zone modifiers (see linux/mmzone.h - low four bits)
44 * Do not put any conditional on these. If necessary modify the definitions
45 * without the underscores and use them consistently. The definitions here may
46 * be used in bit comparisons.
48 #define __GFP_DMA ((__force gfp_t)___GFP_DMA)
49 #define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
50 #define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
51 #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* Page is movable */
52 #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
53 #define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
56 * Page mobility and placement hints
58 * These flags provide hints about how mobile the page is. Pages with similar
59 * mobility are placed within the same pageblocks to minimise problems due
60 * to external fragmentation.
62 * __GFP_MOVABLE (also a zone modifier) indicates that the page can be
63 * moved by page migration during memory compaction or can be reclaimed.
65 * __GFP_RECLAIMABLE is used for slab allocations that specify
66 * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
68 * __GFP_WRITE indicates the caller intends to dirty the page. Where possible,
69 * these pages will be spread between local zones to avoid all the dirty
70 * pages being in one zone (fair zone allocation policy).
72 * __GFP_HARDWALL enforces the cpuset memory allocation policy.
74 * __GFP_THISNODE forces the allocation to be satisified from the requested
75 * node with no fallbacks or placement policy enforcements.
77 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
78 #define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
79 #define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
80 #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
83 * Watermark modifiers -- controls access to emergency reserves
85 * __GFP_HIGH indicates that the caller is high-priority and that granting
86 * the request is necessary before the system can make forward progress.
87 * For example, creating an IO context to clean pages.
89 * __GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
90 * high priority. Users are typically interrupt handlers. This may be
91 * used in conjunction with __GFP_HIGH
93 * __GFP_MEMALLOC allows access to all memory. This should only be used when
94 * the caller guarantees the allocation will allow more memory to be freed
95 * very shortly e.g. process exiting or swapping. Users either should
96 * be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
98 * __GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
99 * This takes precedence over the __GFP_MEMALLOC flag if both are set.
101 * __GFP_NOACCOUNT ignores the accounting for kmemcg limit enforcement.
103 #define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
104 #define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
105 #define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
106 #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
107 #define __GFP_NOACCOUNT ((__force gfp_t)___GFP_NOACCOUNT)
112 * __GFP_IO can start physical IO.
114 * __GFP_FS can call down to the low-level FS. Clearing the flag avoids the
115 * allocator recursing into the filesystem which might already be holding
118 * __GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
119 * This flag can be cleared to avoid unnecessary delays when a fallback
120 * option is available.
122 * __GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
123 * the low watermark is reached and have it reclaim pages until the high
124 * watermark is reached. A caller may wish to clear this flag when fallback
125 * options are available and the reclaim is likely to disrupt the system. The
126 * canonical example is THP allocation where a fallback is cheap but
127 * reclaim/compaction may cause indirect stalls.
129 * __GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
131 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
132 * _might_ fail. This depends upon the particular VM implementation.
134 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
135 * cannot handle allocation failures. New users should be evaluated carefully
136 * (and the flag should be used only when there is no reasonable failure
137 * policy) but it is definitely preferable to use the flag rather than
138 * opencode endless loop around allocator.
140 * __GFP_NORETRY: The VM implementation must not retry indefinitely and will
141 * return NULL when direct reclaim and memory compaction have failed to allow
142 * the allocation to succeed. The OOM killer is not called with the current
145 #define __GFP_IO ((__force gfp_t)___GFP_IO)
146 #define __GFP_FS ((__force gfp_t)___GFP_FS)
147 #define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
148 #define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
149 #define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
150 #define __GFP_REPEAT ((__force gfp_t)___GFP_REPEAT)
151 #define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
152 #define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
157 * __GFP_COLD indicates that the caller does not expect to be used in the near
158 * future. Where possible, a cache-cold page will be returned.
160 * __GFP_NOWARN suppresses allocation failure reports.
162 * __GFP_COMP address compound page metadata.
164 * __GFP_ZERO returns a zeroed page on success.
166 * __GFP_NOTRACK avoids tracking with kmemcheck.
168 * __GFP_NOTRACK_FALSE_POSITIVE is an alias of __GFP_NOTRACK. It's a means of
169 * distinguishing in the source between false positives and allocations that
170 * cannot be supported (e.g. page tables).
172 * __GFP_OTHER_NODE is for allocations that are on a remote node but that
173 * should not be accounted for as a remote allocation in vmstat. A
174 * typical user would be khugepaged collapsing a huge page on a remote
177 #define __GFP_COLD ((__force gfp_t)___GFP_COLD)
178 #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
179 #define __GFP_COMP ((__force gfp_t)___GFP_COMP)
180 #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
181 #define __GFP_NOTRACK ((__force gfp_t)___GFP_NOTRACK)
182 #define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK)
183 #define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE)
185 /* Room for N __GFP_FOO bits */
186 #define __GFP_BITS_SHIFT 26
187 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
190 * Useful GFP flag combinations that are commonly used. It is recommended
191 * that subsystems start with one of these combinations and then set/clear
192 * __GFP_FOO flags as necessary.
194 * GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
195 * watermark is applied to allow access to "atomic reserves"
197 * GFP_KERNEL is typical for kernel-internal allocations. The caller requires
198 * ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
200 * GFP_NOWAIT is for kernel allocations that should not stall for direct
201 * reclaim, start physical IO or use any filesystem callback.
203 * GFP_NOIO will use direct reclaim to discard clean pages or slab pages
204 * that do not require the starting of any physical IO.
206 * GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
208 * GFP_USER is for userspace allocations that also need to be directly
209 * accessibly by the kernel or hardware. It is typically used by hardware
210 * for buffers that are mapped to userspace (e.g. graphics) that hardware
211 * still must DMA to. cpuset limits are enforced for these allocations.
213 * GFP_DMA exists for historical reasons and should be avoided where possible.
214 * The flags indicates that the caller requires that the lowest zone be
215 * used (ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
216 * it would require careful auditing as some users really require it and
217 * others use the flag to avoid lowmem reserves in ZONE_DMA and treat the
218 * lowest zone as a type of emergency reserve.
220 * GFP_DMA32 is similar to GFP_DMA except that the caller requires a 32-bit
223 * GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
224 * do not need to be directly accessible by the kernel but that cannot
225 * move once in use. An example may be a hardware allocation that maps
226 * data directly into userspace but has no addressing limitations.
228 * GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
229 * need direct access to but can use kmap() when access is required. They
230 * are expected to be movable via page reclaim or page migration. Typically,
231 * pages on the LRU would also be allocated with GFP_HIGHUSER_MOVABLE.
233 * GFP_TRANSHUGE is used for THP allocations. They are compound allocations
234 * that will fail quickly if memory is not available and will not wake
237 #define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
238 #define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
239 #define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
240 #define GFP_NOIO (__GFP_RECLAIM)
241 #define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
242 #define GFP_TEMPORARY (__GFP_RECLAIM | __GFP_IO | __GFP_FS | \
244 #define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
245 #define GFP_DMA __GFP_DMA
246 #define GFP_DMA32 __GFP_DMA32
247 #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
248 #define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE)
249 #define GFP_TRANSHUGE ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
250 __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN) & \
251 ~__GFP_KSWAPD_RECLAIM)
253 /* Convert GFP flags to their corresponding migrate type */
254 #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
255 #define GFP_MOVABLE_SHIFT 3
257 static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
259 VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
260 BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
261 BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
263 if (unlikely(page_group_by_mobility_disabled))
264 return MIGRATE_UNMOVABLE;
266 /* Group based on mobility */
267 return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
269 #undef GFP_MOVABLE_MASK
270 #undef GFP_MOVABLE_SHIFT
272 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
274 return (bool __force)(gfp_flags & __GFP_DIRECT_RECLAIM);
278 * gfpflags_normal_context - is gfp_flags a normal sleepable context?
279 * @gfp_flags: gfp_flags to test
281 * Test whether @gfp_flags indicates that the allocation is from the
282 * %current context and allowed to sleep.
284 * An allocation being allowed to block doesn't mean it owns the %current
285 * context. When direct reclaim path tries to allocate memory, the
286 * allocation context is nested inside whatever %current was doing at the
287 * time of the original allocation. The nested allocation may be allowed
288 * to block but modifying anything %current owns can corrupt the outer
289 * context's expectations.
291 * %true result from this function indicates that the allocation context
292 * can sleep and use anything that's associated with %current.
294 static inline bool gfpflags_normal_context(const gfp_t gfp_flags)
296 return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) ==
297 __GFP_DIRECT_RECLAIM;
300 #ifdef CONFIG_HIGHMEM
301 #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
303 #define OPT_ZONE_HIGHMEM ZONE_NORMAL
306 #ifdef CONFIG_ZONE_DMA
307 #define OPT_ZONE_DMA ZONE_DMA
309 #define OPT_ZONE_DMA ZONE_NORMAL
312 #ifdef CONFIG_ZONE_DMA32
313 #define OPT_ZONE_DMA32 ZONE_DMA32
315 #define OPT_ZONE_DMA32 ZONE_NORMAL
319 * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
320 * zone to use given the lowest 4 bits of gfp_t. Entries are ZONE_SHIFT long
321 * and there are 16 of them to cover all possible combinations of
322 * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
324 * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
325 * But GFP_MOVABLE is not only a zone specifier but also an allocation
326 * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
327 * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
332 * 0x1 => DMA or NORMAL
333 * 0x2 => HIGHMEM or NORMAL
334 * 0x3 => BAD (DMA+HIGHMEM)
335 * 0x4 => DMA32 or DMA or NORMAL
336 * 0x5 => BAD (DMA+DMA32)
337 * 0x6 => BAD (HIGHMEM+DMA32)
338 * 0x7 => BAD (HIGHMEM+DMA32+DMA)
339 * 0x8 => NORMAL (MOVABLE+0)
340 * 0x9 => DMA or NORMAL (MOVABLE+DMA)
341 * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
342 * 0xb => BAD (MOVABLE+HIGHMEM+DMA)
343 * 0xc => DMA32 (MOVABLE+DMA32)
344 * 0xd => BAD (MOVABLE+DMA32+DMA)
345 * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
346 * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
348 * ZONES_SHIFT must be <= 2 on 32 bit platforms.
351 #if 16 * ZONES_SHIFT > BITS_PER_LONG
352 #error ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
355 #define GFP_ZONE_TABLE ( \
356 (ZONE_NORMAL << 0 * ZONES_SHIFT) \
357 | (OPT_ZONE_DMA << ___GFP_DMA * ZONES_SHIFT) \
358 | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * ZONES_SHIFT) \
359 | (OPT_ZONE_DMA32 << ___GFP_DMA32 * ZONES_SHIFT) \
360 | (ZONE_NORMAL << ___GFP_MOVABLE * ZONES_SHIFT) \
361 | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * ZONES_SHIFT) \
362 | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * ZONES_SHIFT) \
363 | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * ZONES_SHIFT) \
367 * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
368 * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
369 * entry starting with bit 0. Bit is set if the combination is not
372 #define GFP_ZONE_BAD ( \
373 1 << (___GFP_DMA | ___GFP_HIGHMEM) \
374 | 1 << (___GFP_DMA | ___GFP_DMA32) \
375 | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
376 | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
377 | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
378 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
379 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
380 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
383 static inline enum zone_type gfp_zone(gfp_t flags)
386 int bit = (__force int) (flags & GFP_ZONEMASK);
388 z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
389 ((1 << ZONES_SHIFT) - 1);
390 VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
395 * There is only one page-allocator function, and two main namespaces to
396 * it. The alloc_page*() variants return 'struct page *' and as such
397 * can allocate highmem pages, the *get*page*() variants return
398 * virtual kernel addresses to the allocated page(s).
401 static inline int gfp_zonelist(gfp_t flags)
403 if (IS_ENABLED(CONFIG_NUMA) && unlikely(flags & __GFP_THISNODE))
410 * We get the zone list from the current node and the gfp_mask.
411 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
412 * There are two zonelists per node, one for all zones with memory and
413 * one containing just zones from the node the zonelist belongs to.
415 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
416 * optimized to &contig_page_data at compile-time.
418 static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
420 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
423 #ifndef HAVE_ARCH_FREE_PAGE
424 static inline void arch_free_page(struct page *page, int order) { }
426 #ifndef HAVE_ARCH_ALLOC_PAGE
427 static inline void arch_alloc_page(struct page *page, int order) { }
431 __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
432 struct zonelist *zonelist, nodemask_t *nodemask);
434 static inline struct page *
435 __alloc_pages(gfp_t gfp_mask, unsigned int order,
436 struct zonelist *zonelist)
438 return __alloc_pages_nodemask(gfp_mask, order, zonelist, NULL);
442 * Allocate pages, preferring the node given as nid. The node must be valid and
443 * online. For more general interface, see alloc_pages_node().
445 static inline struct page *
446 __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
448 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
449 VM_WARN_ON(!node_online(nid));
451 return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
455 * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
456 * prefer the current CPU's closest node. Otherwise node must be valid and
459 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
462 if (nid == NUMA_NO_NODE)
465 return __alloc_pages_node(nid, gfp_mask, order);
469 extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
471 static inline struct page *
472 alloc_pages(gfp_t gfp_mask, unsigned int order)
474 return alloc_pages_current(gfp_mask, order);
476 extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
477 struct vm_area_struct *vma, unsigned long addr,
478 int node, bool hugepage);
479 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
480 alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
482 #define alloc_pages(gfp_mask, order) \
483 alloc_pages_node(numa_node_id(), gfp_mask, order)
484 #define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
485 alloc_pages(gfp_mask, order)
486 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
487 alloc_pages(gfp_mask, order)
489 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
490 #define alloc_page_vma(gfp_mask, vma, addr) \
491 alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false)
492 #define alloc_page_vma_node(gfp_mask, vma, addr, node) \
493 alloc_pages_vma(gfp_mask, 0, vma, addr, node, false)
495 extern struct page *alloc_kmem_pages(gfp_t gfp_mask, unsigned int order);
496 extern struct page *alloc_kmem_pages_node(int nid, gfp_t gfp_mask,
499 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
500 extern unsigned long get_zeroed_page(gfp_t gfp_mask);
502 void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
503 void free_pages_exact(void *virt, size_t size);
504 void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
506 #define __get_free_page(gfp_mask) \
507 __get_free_pages((gfp_mask), 0)
509 #define __get_dma_pages(gfp_mask, order) \
510 __get_free_pages((gfp_mask) | GFP_DMA, (order))
512 extern void __free_pages(struct page *page, unsigned int order);
513 extern void free_pages(unsigned long addr, unsigned int order);
514 extern void free_hot_cold_page(struct page *page, bool cold);
515 extern void free_hot_cold_page_list(struct list_head *list, bool cold);
517 struct page_frag_cache;
518 extern void *__alloc_page_frag(struct page_frag_cache *nc,
519 unsigned int fragsz, gfp_t gfp_mask);
520 extern void __free_page_frag(void *addr);
522 extern void __free_kmem_pages(struct page *page, unsigned int order);
523 extern void free_kmem_pages(unsigned long addr, unsigned int order);
525 #define __free_page(page) __free_pages((page), 0)
526 #define free_page(addr) free_pages((addr), 0)
528 void page_alloc_init(void);
529 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
530 void drain_all_pages(struct zone *zone);
531 void drain_local_pages(struct zone *zone);
533 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
534 void page_alloc_init_late(void);
536 static inline void page_alloc_init_late(void)
542 * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
543 * GFP flags are used before interrupts are enabled. Once interrupts are
544 * enabled, it is set to __GFP_BITS_MASK while the system is running. During
545 * hibernation, it is used by PM to avoid I/O during memory allocation while
546 * devices are suspended.
548 extern gfp_t gfp_allowed_mask;
550 /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
551 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
553 extern void pm_restrict_gfp_mask(void);
554 extern void pm_restore_gfp_mask(void);
556 #ifdef CONFIG_PM_SLEEP
557 extern bool pm_suspended_storage(void);
559 static inline bool pm_suspended_storage(void)
563 #endif /* CONFIG_PM_SLEEP */
567 /* The below functions must be run on a range from a single zone. */
568 extern int alloc_contig_range(unsigned long start, unsigned long end,
569 unsigned migratetype);
570 extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
573 extern void init_cma_reserved_pageblock(struct page *page);
577 #endif /* __LINUX_GFP_H */