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 #define ___GFP_CMA 0x4000000u
40 /* If the above are modified, __GFP_BITS_SHIFT may need updating */
43 * Physical address zone modifiers (see linux/mmzone.h - low four bits)
45 * Do not put any conditional on these. If necessary modify the definitions
46 * without the underscores and use them consistently. The definitions here may
47 * be used in bit comparisons.
49 #define __GFP_DMA ((__force gfp_t)___GFP_DMA)
50 #define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
51 #define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
52 #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* Page is movable */
53 #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
54 #define __GFP_CMA ((__force gfp_t)___GFP_CMA)
55 #define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE| \
58 * Page mobility and placement hints
60 * These flags provide hints about how mobile the page is. Pages with similar
61 * mobility are placed within the same pageblocks to minimise problems due
62 * to external fragmentation.
64 * __GFP_MOVABLE (also a zone modifier) indicates that the page can be
65 * moved by page migration during memory compaction or can be reclaimed.
67 * __GFP_RECLAIMABLE is used for slab allocations that specify
68 * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
70 * __GFP_WRITE indicates the caller intends to dirty the page. Where possible,
71 * these pages will be spread between local zones to avoid all the dirty
72 * pages being in one zone (fair zone allocation policy).
74 * __GFP_HARDWALL enforces the cpuset memory allocation policy.
76 * __GFP_THISNODE forces the allocation to be satisified from the requested
77 * node with no fallbacks or placement policy enforcements.
79 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
80 #define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
81 #define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
82 #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
85 * Watermark modifiers -- controls access to emergency reserves
87 * __GFP_HIGH indicates that the caller is high-priority and that granting
88 * the request is necessary before the system can make forward progress.
89 * For example, creating an IO context to clean pages.
91 * __GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
92 * high priority. Users are typically interrupt handlers. This may be
93 * used in conjunction with __GFP_HIGH
95 * __GFP_MEMALLOC allows access to all memory. This should only be used when
96 * the caller guarantees the allocation will allow more memory to be freed
97 * very shortly e.g. process exiting or swapping. Users either should
98 * be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
100 * __GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
101 * This takes precedence over the __GFP_MEMALLOC flag if both are set.
103 * __GFP_NOACCOUNT ignores the accounting for kmemcg limit enforcement.
105 #define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
106 #define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
107 #define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
108 #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
109 #define __GFP_NOACCOUNT ((__force gfp_t)___GFP_NOACCOUNT)
114 * __GFP_IO can start physical IO.
116 * __GFP_FS can call down to the low-level FS. Clearing the flag avoids the
117 * allocator recursing into the filesystem which might already be holding
120 * __GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
121 * This flag can be cleared to avoid unnecessary delays when a fallback
122 * option is available.
124 * __GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
125 * the low watermark is reached and have it reclaim pages until the high
126 * watermark is reached. A caller may wish to clear this flag when fallback
127 * options are available and the reclaim is likely to disrupt the system. The
128 * canonical example is THP allocation where a fallback is cheap but
129 * reclaim/compaction may cause indirect stalls.
131 * __GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
133 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
134 * _might_ fail. This depends upon the particular VM implementation.
136 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
137 * cannot handle allocation failures. New users should be evaluated carefully
138 * (and the flag should be used only when there is no reasonable failure
139 * policy) but it is definitely preferable to use the flag rather than
140 * opencode endless loop around allocator.
142 * __GFP_NORETRY: The VM implementation must not retry indefinitely and will
143 * return NULL when direct reclaim and memory compaction have failed to allow
144 * the allocation to succeed. The OOM killer is not called with the current
147 #define __GFP_IO ((__force gfp_t)___GFP_IO)
148 #define __GFP_FS ((__force gfp_t)___GFP_FS)
149 #define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
150 #define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
151 #define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
152 #define __GFP_REPEAT ((__force gfp_t)___GFP_REPEAT)
153 #define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
154 #define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
159 * __GFP_COLD indicates that the caller does not expect to be used in the near
160 * future. Where possible, a cache-cold page will be returned.
162 * __GFP_NOWARN suppresses allocation failure reports.
164 * __GFP_COMP address compound page metadata.
166 * __GFP_ZERO returns a zeroed page on success.
168 * __GFP_NOTRACK avoids tracking with kmemcheck.
170 * __GFP_NOTRACK_FALSE_POSITIVE is an alias of __GFP_NOTRACK. It's a means of
171 * distinguishing in the source between false positives and allocations that
172 * cannot be supported (e.g. page tables).
174 * __GFP_OTHER_NODE is for allocations that are on a remote node but that
175 * should not be accounted for as a remote allocation in vmstat. A
176 * typical user would be khugepaged collapsing a huge page on a remote
179 #define __GFP_COLD ((__force gfp_t)___GFP_COLD)
180 #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
181 #define __GFP_COMP ((__force gfp_t)___GFP_COMP)
182 #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
183 #define __GFP_NOTRACK ((__force gfp_t)___GFP_NOTRACK)
184 #define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK)
185 #define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE)
187 /* Room for N __GFP_FOO bits */
188 #define __GFP_BITS_SHIFT 27
189 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
192 * Useful GFP flag combinations that are commonly used. It is recommended
193 * that subsystems start with one of these combinations and then set/clear
194 * __GFP_FOO flags as necessary.
196 * GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
197 * watermark is applied to allow access to "atomic reserves"
199 * GFP_KERNEL is typical for kernel-internal allocations. The caller requires
200 * ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
202 * GFP_NOWAIT is for kernel allocations that should not stall for direct
203 * reclaim, start physical IO or use any filesystem callback.
205 * GFP_NOIO will use direct reclaim to discard clean pages or slab pages
206 * that do not require the starting of any physical IO.
208 * GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
210 * GFP_USER is for userspace allocations that also need to be directly
211 * accessibly by the kernel or hardware. It is typically used by hardware
212 * for buffers that are mapped to userspace (e.g. graphics) that hardware
213 * still must DMA to. cpuset limits are enforced for these allocations.
215 * GFP_DMA exists for historical reasons and should be avoided where possible.
216 * The flags indicates that the caller requires that the lowest zone be
217 * used (ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
218 * it would require careful auditing as some users really require it and
219 * others use the flag to avoid lowmem reserves in ZONE_DMA and treat the
220 * lowest zone as a type of emergency reserve.
222 * GFP_DMA32 is similar to GFP_DMA except that the caller requires a 32-bit
225 * GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
226 * do not need to be directly accessible by the kernel but that cannot
227 * move once in use. An example may be a hardware allocation that maps
228 * data directly into userspace but has no addressing limitations.
230 * GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
231 * need direct access to but can use kmap() when access is required. They
232 * are expected to be movable via page reclaim or page migration. Typically,
233 * pages on the LRU would also be allocated with GFP_HIGHUSER_MOVABLE.
235 * GFP_TRANSHUGE is used for THP allocations. They are compound allocations
236 * that will fail quickly if memory is not available and will not wake
239 #define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
240 #define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
241 #define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
242 #define GFP_NOIO (__GFP_RECLAIM)
243 #define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
244 #define GFP_TEMPORARY (__GFP_RECLAIM | __GFP_IO | __GFP_FS | \
246 #define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
247 #define GFP_DMA __GFP_DMA
248 #define GFP_DMA32 __GFP_DMA32
249 #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
250 #define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE)
251 #define GFP_TRANSHUGE ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
252 __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN) & \
253 ~__GFP_KSWAPD_RECLAIM)
255 /* Convert GFP flags to their corresponding migrate type */
256 #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
257 #define GFP_MOVABLE_SHIFT 3
259 static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
261 VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
262 BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
263 BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
265 if (unlikely(page_group_by_mobility_disabled))
266 return MIGRATE_UNMOVABLE;
268 /* Group based on mobility */
270 return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
272 return ((gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT) |
273 ((gfp_flags & __GFP_CMA) != 0);
276 #undef GFP_MOVABLE_MASK
277 #undef GFP_MOVABLE_SHIFT
279 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
281 return (bool __force)(gfp_flags & __GFP_DIRECT_RECLAIM);
285 * gfpflags_normal_context - is gfp_flags a normal sleepable context?
286 * @gfp_flags: gfp_flags to test
288 * Test whether @gfp_flags indicates that the allocation is from the
289 * %current context and allowed to sleep.
291 * An allocation being allowed to block doesn't mean it owns the %current
292 * context. When direct reclaim path tries to allocate memory, the
293 * allocation context is nested inside whatever %current was doing at the
294 * time of the original allocation. The nested allocation may be allowed
295 * to block but modifying anything %current owns can corrupt the outer
296 * context's expectations.
298 * %true result from this function indicates that the allocation context
299 * can sleep and use anything that's associated with %current.
301 static inline bool gfpflags_normal_context(const gfp_t gfp_flags)
303 return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) ==
304 __GFP_DIRECT_RECLAIM;
307 #ifdef CONFIG_HIGHMEM
308 #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
310 #define OPT_ZONE_HIGHMEM ZONE_NORMAL
313 #ifdef CONFIG_ZONE_DMA
314 #define OPT_ZONE_DMA ZONE_DMA
316 #define OPT_ZONE_DMA ZONE_NORMAL
319 #ifdef CONFIG_ZONE_DMA32
320 #define OPT_ZONE_DMA32 ZONE_DMA32
322 #define OPT_ZONE_DMA32 ZONE_NORMAL
326 * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
327 * zone to use given the lowest 4 bits of gfp_t. Entries are ZONE_SHIFT long
328 * and there are 16 of them to cover all possible combinations of
329 * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
331 * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
332 * But GFP_MOVABLE is not only a zone specifier but also an allocation
333 * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
334 * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
339 * 0x1 => DMA or NORMAL
340 * 0x2 => HIGHMEM or NORMAL
341 * 0x3 => BAD (DMA+HIGHMEM)
342 * 0x4 => DMA32 or DMA or NORMAL
343 * 0x5 => BAD (DMA+DMA32)
344 * 0x6 => BAD (HIGHMEM+DMA32)
345 * 0x7 => BAD (HIGHMEM+DMA32+DMA)
346 * 0x8 => NORMAL (MOVABLE+0)
347 * 0x9 => DMA or NORMAL (MOVABLE+DMA)
348 * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
349 * 0xb => BAD (MOVABLE+HIGHMEM+DMA)
350 * 0xc => DMA32 (MOVABLE+DMA32)
351 * 0xd => BAD (MOVABLE+DMA32+DMA)
352 * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
353 * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
355 * ZONES_SHIFT must be <= 2 on 32 bit platforms.
358 #if 16 * ZONES_SHIFT > BITS_PER_LONG
359 #error ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
362 #define GFP_ZONE_TABLE ( \
363 (ZONE_NORMAL << 0 * ZONES_SHIFT) \
364 | (OPT_ZONE_DMA << ___GFP_DMA * ZONES_SHIFT) \
365 | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * ZONES_SHIFT) \
366 | (OPT_ZONE_DMA32 << ___GFP_DMA32 * ZONES_SHIFT) \
367 | (ZONE_NORMAL << ___GFP_MOVABLE * ZONES_SHIFT) \
368 | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * ZONES_SHIFT) \
369 | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * ZONES_SHIFT) \
370 | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * ZONES_SHIFT) \
374 * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
375 * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
376 * entry starting with bit 0. Bit is set if the combination is not
379 #define GFP_ZONE_BAD ( \
380 1 << (___GFP_DMA | ___GFP_HIGHMEM) \
381 | 1 << (___GFP_DMA | ___GFP_DMA32) \
382 | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
383 | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
384 | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
385 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
386 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
387 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
390 static inline enum zone_type gfp_zone(gfp_t flags)
393 int bit = (__force int) (flags & GFP_ZONEMASK);
395 z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
396 ((1 << ZONES_SHIFT) - 1);
397 VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
402 * There is only one page-allocator function, and two main namespaces to
403 * it. The alloc_page*() variants return 'struct page *' and as such
404 * can allocate highmem pages, the *get*page*() variants return
405 * virtual kernel addresses to the allocated page(s).
408 static inline int gfp_zonelist(gfp_t flags)
410 if (IS_ENABLED(CONFIG_NUMA) && unlikely(flags & __GFP_THISNODE))
417 * We get the zone list from the current node and the gfp_mask.
418 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
419 * There are two zonelists per node, one for all zones with memory and
420 * one containing just zones from the node the zonelist belongs to.
422 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
423 * optimized to &contig_page_data at compile-time.
425 static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
427 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
430 #ifndef HAVE_ARCH_FREE_PAGE
431 static inline void arch_free_page(struct page *page, int order) { }
433 #ifndef HAVE_ARCH_ALLOC_PAGE
434 static inline void arch_alloc_page(struct page *page, int order) { }
438 __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
439 struct zonelist *zonelist, nodemask_t *nodemask);
441 static inline struct page *
442 __alloc_pages(gfp_t gfp_mask, unsigned int order,
443 struct zonelist *zonelist)
445 return __alloc_pages_nodemask(gfp_mask, order, zonelist, NULL);
449 * Allocate pages, preferring the node given as nid. The node must be valid and
450 * online. For more general interface, see alloc_pages_node().
452 static inline struct page *
453 __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
455 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
456 VM_WARN_ON(!node_online(nid));
458 return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
462 * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
463 * prefer the current CPU's closest node. Otherwise node must be valid and
466 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
469 if (nid == NUMA_NO_NODE)
472 return __alloc_pages_node(nid, gfp_mask, order);
476 extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
478 static inline struct page *
479 alloc_pages(gfp_t gfp_mask, unsigned int order)
481 return alloc_pages_current(gfp_mask, order);
483 extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
484 struct vm_area_struct *vma, unsigned long addr,
485 int node, bool hugepage);
486 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
487 alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
489 #define alloc_pages(gfp_mask, order) \
490 alloc_pages_node(numa_node_id(), gfp_mask, order)
491 #define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
492 alloc_pages(gfp_mask, order)
493 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
494 alloc_pages(gfp_mask, order)
496 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
497 #define alloc_page_vma(gfp_mask, vma, addr) \
498 alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false)
499 #define alloc_page_vma_node(gfp_mask, vma, addr, node) \
500 alloc_pages_vma(gfp_mask, 0, vma, addr, node, false)
502 extern struct page *alloc_kmem_pages(gfp_t gfp_mask, unsigned int order);
503 extern struct page *alloc_kmem_pages_node(int nid, gfp_t gfp_mask,
506 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
507 extern unsigned long get_zeroed_page(gfp_t gfp_mask);
509 void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
510 void free_pages_exact(void *virt, size_t size);
511 void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
513 #define __get_free_page(gfp_mask) \
514 __get_free_pages((gfp_mask), 0)
516 #define __get_dma_pages(gfp_mask, order) \
517 __get_free_pages((gfp_mask) | GFP_DMA, (order))
519 extern void __free_pages(struct page *page, unsigned int order);
520 extern void free_pages(unsigned long addr, unsigned int order);
521 extern void free_hot_cold_page(struct page *page, bool cold);
522 extern void free_hot_cold_page_list(struct list_head *list, bool cold);
524 struct page_frag_cache;
525 extern void *__alloc_page_frag(struct page_frag_cache *nc,
526 unsigned int fragsz, gfp_t gfp_mask);
527 extern void __free_page_frag(void *addr);
529 extern void __free_kmem_pages(struct page *page, unsigned int order);
530 extern void free_kmem_pages(unsigned long addr, unsigned int order);
532 #define __free_page(page) __free_pages((page), 0)
533 #define free_page(addr) free_pages((addr), 0)
535 void page_alloc_init(void);
536 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
537 void drain_all_pages(struct zone *zone);
538 void drain_local_pages(struct zone *zone);
540 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
541 void page_alloc_init_late(void);
543 static inline void page_alloc_init_late(void)
549 * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
550 * GFP flags are used before interrupts are enabled. Once interrupts are
551 * enabled, it is set to __GFP_BITS_MASK while the system is running. During
552 * hibernation, it is used by PM to avoid I/O during memory allocation while
553 * devices are suspended.
555 extern gfp_t gfp_allowed_mask;
557 /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
558 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
560 extern void pm_restrict_gfp_mask(void);
561 extern void pm_restore_gfp_mask(void);
563 #ifdef CONFIG_PM_SLEEP
564 extern bool pm_suspended_storage(void);
566 static inline bool pm_suspended_storage(void)
570 #endif /* CONFIG_PM_SLEEP */
574 /* The below functions must be run on a range from a single zone. */
575 extern int alloc_contig_range(unsigned long start, unsigned long end,
576 unsigned migratetype);
577 extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
580 extern void init_cma_reserved_pageblock(struct page *page);
584 #endif /* __LINUX_GFP_H */