1 #ifndef __LINUX_GFP_H
2 #define __LINUX_GFP_H
3
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>
9
10 struct vm_area_struct;
11
12 /*
13 * In case of changes, please don't forget to update
14 * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
15 */
16
17 /* Plain integer GFP bitmasks. Do not use this directly. */
18 #define ___GFP_DMA 0x01u
19 #define ___GFP_HIGHMEM 0x02u
20 #define ___GFP_DMA32 0x04u
21 #define ___GFP_MOVABLE 0x08u
22 #define ___GFP_RECLAIMABLE 0x10u
23 #define ___GFP_HIGH 0x20u
24 #define ___GFP_IO 0x40u
25 #define ___GFP_FS 0x80u
26 #define ___GFP_COLD 0x100u
27 #define ___GFP_NOWARN 0x200u
28 #define ___GFP_REPEAT 0x400u
29 #define ___GFP_NOFAIL 0x800u
30 #define ___GFP_NORETRY 0x1000u
31 #define ___GFP_MEMALLOC 0x2000u
32 #define ___GFP_COMP 0x4000u
33 #define ___GFP_ZERO 0x8000u
34 #define ___GFP_NOMEMALLOC 0x10000u
35 #define ___GFP_HARDWALL 0x20000u
36 #define ___GFP_THISNODE 0x40000u
37 #define ___GFP_ATOMIC 0x80000u
38 #define ___GFP_ACCOUNT 0x100000u
39 #define ___GFP_NOTRACK 0x200000u
40 #define ___GFP_DIRECT_RECLAIM 0x400000u
41 #define ___GFP_OTHER_NODE 0x800000u
42 #define ___GFP_WRITE 0x1000000u
43 #define ___GFP_KSWAPD_RECLAIM 0x2000000u
44 /* If the above are modified, __GFP_BITS_SHIFT may need updating */
45
46 /*
47 * Physical address zone modifiers (see linux/mmzone.h - low four bits)
48 *
49 * Do not put any conditional on these. If necessary modify the definitions
50 * without the underscores and use them consistently. The definitions here may
51 * be used in bit comparisons.
52 */
53 #define __GFP_DMA ((__force gfp_t)___GFP_DMA)
54 #define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
55 #define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
56 #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
57 #define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
58
59 /*
60 * Page mobility and placement hints
61 *
62 * These flags provide hints about how mobile the page is. Pages with similar
63 * mobility are placed within the same pageblocks to minimise problems due
64 * to external fragmentation.
65 *
66 * __GFP_MOVABLE (also a zone modifier) indicates that the page can be
67 * moved by page migration during memory compaction or can be reclaimed.
68 *
69 * __GFP_RECLAIMABLE is used for slab allocations that specify
70 * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
71 *
72 * __GFP_WRITE indicates the caller intends to dirty the page. Where possible,
73 * these pages will be spread between local zones to avoid all the dirty
74 * pages being in one zone (fair zone allocation policy).
75 *
76 * __GFP_HARDWALL enforces the cpuset memory allocation policy.
77 *
78 * __GFP_THISNODE forces the allocation to be satisified from the requested
79 * node with no fallbacks or placement policy enforcements.
80 *
81 * __GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
82 */
83 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
84 #define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
85 #define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
86 #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
87 #define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT)
88
89 /*
90 * Watermark modifiers -- controls access to emergency reserves
91 *
92 * __GFP_HIGH indicates that the caller is high-priority and that granting
93 * the request is necessary before the system can make forward progress.
94 * For example, creating an IO context to clean pages.
95 *
96 * __GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
97 * high priority. Users are typically interrupt handlers. This may be
98 * used in conjunction with __GFP_HIGH
99 *
100 * __GFP_MEMALLOC allows access to all memory. This should only be used when
101 * the caller guarantees the allocation will allow more memory to be freed
102 * very shortly e.g. process exiting or swapping. Users either should
103 * be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
104 *
105 * __GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
106 * This takes precedence over the __GFP_MEMALLOC flag if both are set.
107 */
108 #define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
109 #define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
110 #define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
111 #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
112
113 /*
114 * Reclaim modifiers
115 *
116 * __GFP_IO can start physical IO.
117 *
118 * __GFP_FS can call down to the low-level FS. Clearing the flag avoids the
119 * allocator recursing into the filesystem which might already be holding
120 * locks.
121 *
122 * __GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
123 * This flag can be cleared to avoid unnecessary delays when a fallback
124 * option is available.
125 *
126 * __GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
127 * the low watermark is reached and have it reclaim pages until the high
128 * watermark is reached. A caller may wish to clear this flag when fallback
129 * options are available and the reclaim is likely to disrupt the system. The
130 * canonical example is THP allocation where a fallback is cheap but
131 * reclaim/compaction may cause indirect stalls.
132 *
133 * __GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
134 *
135 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
136 * _might_ fail. This depends upon the particular VM implementation.
137 *
138 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
139 * cannot handle allocation failures. New users should be evaluated carefully
140 * (and the flag should be used only when there is no reasonable failure
141 * policy) but it is definitely preferable to use the flag rather than
142 * opencode endless loop around allocator.
143 *
144 * __GFP_NORETRY: The VM implementation must not retry indefinitely and will
145 * return NULL when direct reclaim and memory compaction have failed to allow
146 * the allocation to succeed. The OOM killer is not called with the current
147 * implementation.
148 */
149 #define __GFP_IO ((__force gfp_t)___GFP_IO)
150 #define __GFP_FS ((__force gfp_t)___GFP_FS)
151 #define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
152 #define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
153 #define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
154 #define __GFP_REPEAT ((__force gfp_t)___GFP_REPEAT)
155 #define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
156 #define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
157
158 /*
159 * Action modifiers
160 *
161 * __GFP_COLD indicates that the caller does not expect to be used in the near
162 * future. Where possible, a cache-cold page will be returned.
163 *
164 * __GFP_NOWARN suppresses allocation failure reports.
165 *
166 * __GFP_COMP address compound page metadata.
167 *
168 * __GFP_ZERO returns a zeroed page on success.
169 *
170 * __GFP_NOTRACK avoids tracking with kmemcheck.
171 *
172 * __GFP_NOTRACK_FALSE_POSITIVE is an alias of __GFP_NOTRACK. It's a means of
173 * distinguishing in the source between false positives and allocations that
174 * cannot be supported (e.g. page tables).
175 *
176 * __GFP_OTHER_NODE is for allocations that are on a remote node but that
177 * should not be accounted for as a remote allocation in vmstat. A
178 * typical user would be khugepaged collapsing a huge page on a remote
179 * node.
180 */
181 #define __GFP_COLD ((__force gfp_t)___GFP_COLD)
182 #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
183 #define __GFP_COMP ((__force gfp_t)___GFP_COMP)
184 #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
185 #define __GFP_NOTRACK ((__force gfp_t)___GFP_NOTRACK)
186 #define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK)
187 #define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE)
188
189 /* Room for N __GFP_FOO bits */
190 #define __GFP_BITS_SHIFT 26
191 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
192
193 /*
194 * Useful GFP flag combinations that are commonly used. It is recommended
195 * that subsystems start with one of these combinations and then set/clear
196 * __GFP_FOO flags as necessary.
197 *
198 * GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
199 * watermark is applied to allow access to "atomic reserves"
200 *
201 * GFP_KERNEL is typical for kernel-internal allocations. The caller requires
202 * ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
203 *
204 * GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is
205 * accounted to kmemcg.
206 *
207 * GFP_NOWAIT is for kernel allocations that should not stall for direct
208 * reclaim, start physical IO or use any filesystem callback.
209 *
210 * GFP_NOIO will use direct reclaim to discard clean pages or slab pages
211 * that do not require the starting of any physical IO.
212 *
213 * GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
214 *
215 * GFP_USER is for userspace allocations that also need to be directly
216 * accessibly by the kernel or hardware. It is typically used by hardware
217 * for buffers that are mapped to userspace (e.g. graphics) that hardware
218 * still must DMA to. cpuset limits are enforced for these allocations.
219 *
220 * GFP_DMA exists for historical reasons and should be avoided where possible.
221 * The flags indicates that the caller requires that the lowest zone be
222 * used (ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
223 * it would require careful auditing as some users really require it and
224 * others use the flag to avoid lowmem reserves in ZONE_DMA and treat the
225 * lowest zone as a type of emergency reserve.
226 *
227 * GFP_DMA32 is similar to GFP_DMA except that the caller requires a 32-bit
228 * address.
229 *
230 * GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
231 * do not need to be directly accessible by the kernel but that cannot
232 * move once in use. An example may be a hardware allocation that maps
233 * data directly into userspace but has no addressing limitations.
234 *
235 * GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
236 * need direct access to but can use kmap() when access is required. They
237 * are expected to be movable via page reclaim or page migration. Typically,
238 * pages on the LRU would also be allocated with GFP_HIGHUSER_MOVABLE.
239 *
240 * GFP_TRANSHUGE and GFP_TRANSHUGE_LIGHT are used for THP allocations. They are
241 * compound allocations that will generally fail quickly if memory is not
242 * available and will not wake kswapd/kcompactd on failure. The _LIGHT
243 * version does not attempt reclaim/compaction at all and is by default used
244 * in page fault path, while the non-light is used by khugepaged.
245 */
246 #define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
247 #define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
248 #define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT)
249 #define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
250 #define GFP_NOIO (__GFP_RECLAIM)
251 #define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
252 #define GFP_TEMPORARY (__GFP_RECLAIM | __GFP_IO | __GFP_FS | \
253 __GFP_RECLAIMABLE)
254 #define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
255 #define GFP_DMA __GFP_DMA
256 #define GFP_DMA32 __GFP_DMA32
257 #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
258 #define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE)
259 #define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
260 __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
261 #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
262
263 /* Convert GFP flags to their corresponding migrate type */
264 #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
265 #define GFP_MOVABLE_SHIFT 3
266
gfpflags_to_migratetype(const gfp_t gfp_flags)267 static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
268 {
269 VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
270 BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
271 BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
272
273 if (unlikely(page_group_by_mobility_disabled))
274 return MIGRATE_UNMOVABLE;
275
276 /* Group based on mobility */
277 return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
278 }
279 #undef GFP_MOVABLE_MASK
280 #undef GFP_MOVABLE_SHIFT
281
gfpflags_allow_blocking(const gfp_t gfp_flags)282 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
283 {
284 return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
285 }
286
287 #ifdef CONFIG_HIGHMEM
288 #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
289 #else
290 #define OPT_ZONE_HIGHMEM ZONE_NORMAL
291 #endif
292
293 #ifdef CONFIG_ZONE_DMA
294 #define OPT_ZONE_DMA ZONE_DMA
295 #else
296 #define OPT_ZONE_DMA ZONE_NORMAL
297 #endif
298
299 #ifdef CONFIG_ZONE_DMA32
300 #define OPT_ZONE_DMA32 ZONE_DMA32
301 #else
302 #define OPT_ZONE_DMA32 ZONE_NORMAL
303 #endif
304
305 /*
306 * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
307 * zone to use given the lowest 4 bits of gfp_t. Entries are ZONE_SHIFT long
308 * and there are 16 of them to cover all possible combinations of
309 * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
310 *
311 * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
312 * But GFP_MOVABLE is not only a zone specifier but also an allocation
313 * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
314 * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
315 *
316 * bit result
317 * =================
318 * 0x0 => NORMAL
319 * 0x1 => DMA or NORMAL
320 * 0x2 => HIGHMEM or NORMAL
321 * 0x3 => BAD (DMA+HIGHMEM)
322 * 0x4 => DMA32 or DMA or NORMAL
323 * 0x5 => BAD (DMA+DMA32)
324 * 0x6 => BAD (HIGHMEM+DMA32)
325 * 0x7 => BAD (HIGHMEM+DMA32+DMA)
326 * 0x8 => NORMAL (MOVABLE+0)
327 * 0x9 => DMA or NORMAL (MOVABLE+DMA)
328 * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
329 * 0xb => BAD (MOVABLE+HIGHMEM+DMA)
330 * 0xc => DMA32 (MOVABLE+DMA32)
331 * 0xd => BAD (MOVABLE+DMA32+DMA)
332 * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
333 * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
334 *
335 * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
336 */
337
338 #if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
339 /* ZONE_DEVICE is not a valid GFP zone specifier */
340 #define GFP_ZONES_SHIFT 2
341 #else
342 #define GFP_ZONES_SHIFT ZONES_SHIFT
343 #endif
344
345 #if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
346 #error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
347 #endif
348
349 #define GFP_ZONE_TABLE ( \
350 (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \
351 | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \
352 | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \
353 | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \
354 | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \
355 | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \
356 | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
357 | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\
358 )
359
360 /*
361 * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
362 * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
363 * entry starting with bit 0. Bit is set if the combination is not
364 * allowed.
365 */
366 #define GFP_ZONE_BAD ( \
367 1 << (___GFP_DMA | ___GFP_HIGHMEM) \
368 | 1 << (___GFP_DMA | ___GFP_DMA32) \
369 | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
370 | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
371 | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
372 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
373 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
374 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
375 )
376
gfp_zone(gfp_t flags)377 static inline enum zone_type gfp_zone(gfp_t flags)
378 {
379 enum zone_type z;
380 int bit = (__force int) (flags & GFP_ZONEMASK);
381
382 z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) &
383 ((1 << GFP_ZONES_SHIFT) - 1);
384 VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
385 return z;
386 }
387
388 /*
389 * There is only one page-allocator function, and two main namespaces to
390 * it. The alloc_page*() variants return 'struct page *' and as such
391 * can allocate highmem pages, the *get*page*() variants return
392 * virtual kernel addresses to the allocated page(s).
393 */
394
gfp_zonelist(gfp_t flags)395 static inline int gfp_zonelist(gfp_t flags)
396 {
397 #ifdef CONFIG_NUMA
398 if (unlikely(flags & __GFP_THISNODE))
399 return ZONELIST_NOFALLBACK;
400 #endif
401 return ZONELIST_FALLBACK;
402 }
403
404 /*
405 * We get the zone list from the current node and the gfp_mask.
406 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
407 * There are two zonelists per node, one for all zones with memory and
408 * one containing just zones from the node the zonelist belongs to.
409 *
410 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
411 * optimized to &contig_page_data at compile-time.
412 */
node_zonelist(int nid,gfp_t flags)413 static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
414 {
415 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
416 }
417
418 #ifndef HAVE_ARCH_FREE_PAGE
arch_free_page(struct page * page,int order)419 static inline void arch_free_page(struct page *page, int order) { }
420 #endif
421 #ifndef HAVE_ARCH_ALLOC_PAGE
arch_alloc_page(struct page * page,int order)422 static inline void arch_alloc_page(struct page *page, int order) { }
423 #endif
424
425 struct page *
426 __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
427 struct zonelist *zonelist, nodemask_t *nodemask);
428
429 static inline struct page *
__alloc_pages(gfp_t gfp_mask,unsigned int order,struct zonelist * zonelist)430 __alloc_pages(gfp_t gfp_mask, unsigned int order,
431 struct zonelist *zonelist)
432 {
433 return __alloc_pages_nodemask(gfp_mask, order, zonelist, NULL);
434 }
435
436 /*
437 * Allocate pages, preferring the node given as nid. The node must be valid and
438 * online. For more general interface, see alloc_pages_node().
439 */
440 static inline struct page *
__alloc_pages_node(int nid,gfp_t gfp_mask,unsigned int order)441 __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
442 {
443 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
444 VM_WARN_ON(!node_online(nid));
445
446 return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
447 }
448
449 /*
450 * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
451 * prefer the current CPU's closest node. Otherwise node must be valid and
452 * online.
453 */
alloc_pages_node(int nid,gfp_t gfp_mask,unsigned int order)454 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
455 unsigned int order)
456 {
457 if (nid == NUMA_NO_NODE)
458 nid = numa_mem_id();
459
460 return __alloc_pages_node(nid, gfp_mask, order);
461 }
462
463 #ifdef CONFIG_NUMA
464 extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
465
466 static inline struct page *
alloc_pages(gfp_t gfp_mask,unsigned int order)467 alloc_pages(gfp_t gfp_mask, unsigned int order)
468 {
469 return alloc_pages_current(gfp_mask, order);
470 }
471 extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
472 struct vm_area_struct *vma, unsigned long addr,
473 int node, bool hugepage);
474 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
475 alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
476 #else
477 #define alloc_pages(gfp_mask, order) \
478 alloc_pages_node(numa_node_id(), gfp_mask, order)
479 #define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
480 alloc_pages(gfp_mask, order)
481 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
482 alloc_pages(gfp_mask, order)
483 #endif
484 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
485 #define alloc_page_vma(gfp_mask, vma, addr) \
486 alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false)
487 #define alloc_page_vma_node(gfp_mask, vma, addr, node) \
488 alloc_pages_vma(gfp_mask, 0, vma, addr, node, false)
489
490 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
491 extern unsigned long get_zeroed_page(gfp_t gfp_mask);
492
493 void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
494 void free_pages_exact(void *virt, size_t size);
495 void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
496
497 #define __get_free_page(gfp_mask) \
498 __get_free_pages((gfp_mask), 0)
499
500 #define __get_dma_pages(gfp_mask, order) \
501 __get_free_pages((gfp_mask) | GFP_DMA, (order))
502
503 extern void __free_pages(struct page *page, unsigned int order);
504 extern void free_pages(unsigned long addr, unsigned int order);
505 extern void free_hot_cold_page(struct page *page, bool cold);
506 extern void free_hot_cold_page_list(struct list_head *list, bool cold);
507
508 struct page_frag_cache;
509 extern void *__alloc_page_frag(struct page_frag_cache *nc,
510 unsigned int fragsz, gfp_t gfp_mask);
511 extern void __free_page_frag(void *addr);
512
513 #define __free_page(page) __free_pages((page), 0)
514 #define free_page(addr) free_pages((addr), 0)
515
516 void page_alloc_init(void);
517 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
518 void drain_all_pages(struct zone *zone);
519 void drain_local_pages(void *zone);
520
521 void page_alloc_init_late(void);
522
523 /*
524 * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
525 * GFP flags are used before interrupts are enabled. Once interrupts are
526 * enabled, it is set to __GFP_BITS_MASK while the system is running. During
527 * hibernation, it is used by PM to avoid I/O during memory allocation while
528 * devices are suspended.
529 */
530 extern gfp_t gfp_allowed_mask;
531
532 /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
533 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
534
535 extern void pm_restrict_gfp_mask(void);
536 extern void pm_restore_gfp_mask(void);
537
538 #ifdef CONFIG_PM_SLEEP
539 extern bool pm_suspended_storage(void);
540 #else
pm_suspended_storage(void)541 static inline bool pm_suspended_storage(void)
542 {
543 return false;
544 }
545 #endif /* CONFIG_PM_SLEEP */
546
547 #if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
548 /* The below functions must be run on a range from a single zone. */
549 extern int alloc_contig_range(unsigned long start, unsigned long end,
550 unsigned migratetype);
551 extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
552 #endif
553
554 #ifdef CONFIG_CMA
555 /* CMA stuff */
556 extern void init_cma_reserved_pageblock(struct page *page);
557 #endif
558
559 #endif /* __LINUX_GFP_H */
560