1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_GFP_H
3#define __LINUX_GFP_H
4
5#include <linux/mmdebug.h>
6#include <linux/mmzone.h>
7#include <linux/stddef.h>
8#include <linux/linkage.h>
9#include <linux/topology.h>
10
11struct vm_area_struct;
12
13/*
14 * In case of changes, please don't forget to update
15 * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
16 */
17
18/* Plain integer GFP bitmasks. Do not use this directly. */
19#define ___GFP_DMA 0x01u
20#define ___GFP_HIGHMEM 0x02u
21#define ___GFP_DMA32 0x04u
22#define ___GFP_MOVABLE 0x08u
23#define ___GFP_RECLAIMABLE 0x10u
24#define ___GFP_HIGH 0x20u
25#define ___GFP_IO 0x40u
26#define ___GFP_FS 0x80u
27#define ___GFP_WRITE 0x100u
28#define ___GFP_NOWARN 0x200u
29#define ___GFP_RETRY_MAYFAIL 0x400u
30#define ___GFP_NOFAIL 0x800u
31#define ___GFP_NORETRY 0x1000u
32#define ___GFP_MEMALLOC 0x2000u
33#define ___GFP_COMP 0x4000u
34#define ___GFP_ZERO 0x8000u
35#define ___GFP_NOMEMALLOC 0x10000u
36#define ___GFP_HARDWALL 0x20000u
37#define ___GFP_THISNODE 0x40000u
38#define ___GFP_ATOMIC 0x80000u
39#define ___GFP_ACCOUNT 0x100000u
40#define ___GFP_DIRECT_RECLAIM 0x200000u
41#define ___GFP_KSWAPD_RECLAIM 0x400000u
42#ifdef CONFIG_LOCKDEP
43#define ___GFP_NOLOCKDEP 0x800000u
44#else
45#define ___GFP_NOLOCKDEP 0
46#endif
47/* If the above are modified, __GFP_BITS_SHIFT may need updating */
48
49/*
50 * Physical address zone modifiers (see linux/mmzone.h - low four bits)
51 *
52 * Do not put any conditional on these. If necessary modify the definitions
53 * without the underscores and use them consistently. The definitions here may
54 * be used in bit comparisons.
55 */
56#define __GFP_DMA ((__force gfp_t)___GFP_DMA)
57#define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
58#define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
59#define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
60#define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
61
62/*
63 * Page mobility and placement hints
64 *
65 * These flags provide hints about how mobile the page is. Pages with similar
66 * mobility are placed within the same pageblocks to minimise problems due
67 * to external fragmentation.
68 *
69 * __GFP_MOVABLE (also a zone modifier) indicates that the page can be
70 * moved by page migration during memory compaction or can be reclaimed.
71 *
72 * __GFP_RECLAIMABLE is used for slab allocations that specify
73 * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
74 *
75 * __GFP_WRITE indicates the caller intends to dirty the page. Where possible,
76 * these pages will be spread between local zones to avoid all the dirty
77 * pages being in one zone (fair zone allocation policy).
78 *
79 * __GFP_HARDWALL enforces the cpuset memory allocation policy.
80 *
81 * __GFP_THISNODE forces the allocation to be satisified from the requested
82 * node with no fallbacks or placement policy enforcements.
83 *
84 * __GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
85 */
86#define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
87#define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
88#define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
89#define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
90#define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT)
91
92/*
93 * Watermark modifiers -- controls access to emergency reserves
94 *
95 * __GFP_HIGH indicates that the caller is high-priority and that granting
96 * the request is necessary before the system can make forward progress.
97 * For example, creating an IO context to clean pages.
98 *
99 * __GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
100 * high priority. Users are typically interrupt handlers. This may be
101 * used in conjunction with __GFP_HIGH
102 *
103 * __GFP_MEMALLOC allows access to all memory. This should only be used when
104 * the caller guarantees the allocation will allow more memory to be freed
105 * very shortly e.g. process exiting or swapping. Users either should
106 * be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
107 *
108 * __GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
109 * This takes precedence over the __GFP_MEMALLOC flag if both are set.
110 */
111#define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
112#define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
113#define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
114#define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
115
116/*
117 * Reclaim modifiers
118 *
119 * __GFP_IO can start physical IO.
120 *
121 * __GFP_FS can call down to the low-level FS. Clearing the flag avoids the
122 * allocator recursing into the filesystem which might already be holding
123 * locks.
124 *
125 * __GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
126 * This flag can be cleared to avoid unnecessary delays when a fallback
127 * option is available.
128 *
129 * __GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
130 * the low watermark is reached and have it reclaim pages until the high
131 * watermark is reached. A caller may wish to clear this flag when fallback
132 * options are available and the reclaim is likely to disrupt the system. The
133 * canonical example is THP allocation where a fallback is cheap but
134 * reclaim/compaction may cause indirect stalls.
135 *
136 * __GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
137 *
138 * The default allocator behavior depends on the request size. We have a concept
139 * of so called costly allocations (with order > PAGE_ALLOC_COSTLY_ORDER).
140 * !costly allocations are too essential to fail so they are implicitly
141 * non-failing by default (with some exceptions like OOM victims might fail so
142 * the caller still has to check for failures) while costly requests try to be
143 * not disruptive and back off even without invoking the OOM killer.
144 * The following three modifiers might be used to override some of these
145 * implicit rules
146 *
147 * __GFP_NORETRY: The VM implementation will try only very lightweight
148 * memory direct reclaim to get some memory under memory pressure (thus
149 * it can sleep). It will avoid disruptive actions like OOM killer. The
150 * caller must handle the failure which is quite likely to happen under
151 * heavy memory pressure. The flag is suitable when failure can easily be
152 * handled at small cost, such as reduced throughput
153 *
154 * __GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim
155 * procedures that have previously failed if there is some indication
156 * that progress has been made else where. It can wait for other
157 * tasks to attempt high level approaches to freeing memory such as
158 * compaction (which removes fragmentation) and page-out.
159 * There is still a definite limit to the number of retries, but it is
160 * a larger limit than with __GFP_NORETRY.
161 * Allocations with this flag may fail, but only when there is
162 * genuinely little unused memory. While these allocations do not
163 * directly trigger the OOM killer, their failure indicates that
164 * the system is likely to need to use the OOM killer soon. The
165 * caller must handle failure, but can reasonably do so by failing
166 * a higher-level request, or completing it only in a much less
167 * efficient manner.
168 * If the allocation does fail, and the caller is in a position to
169 * free some non-essential memory, doing so could benefit the system
170 * as a whole.
171 *
172 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
173 * cannot handle allocation failures. The allocation could block
174 * indefinitely but will never return with failure. Testing for
175 * failure is pointless.
176 * New users should be evaluated carefully (and the flag should be
177 * used only when there is no reasonable failure policy) but it is
178 * definitely preferable to use the flag rather than opencode endless
179 * loop around allocator.
180 * Using this flag for costly allocations is _highly_ discouraged.
181 */
182#define __GFP_IO ((__force gfp_t)___GFP_IO)
183#define __GFP_FS ((__force gfp_t)___GFP_FS)
184#define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
185#define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
186#define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
187#define __GFP_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL)
188#define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
189#define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
190
191/*
192 * Action modifiers
193 *
194 * __GFP_NOWARN suppresses allocation failure reports.
195 *
196 * __GFP_COMP address compound page metadata.
197 *
198 * __GFP_ZERO returns a zeroed page on success.
199 */
200#define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
201#define __GFP_COMP ((__force gfp_t)___GFP_COMP)
202#define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
203
204/* Disable lockdep for GFP context tracking */
205#define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
206
207/* Room for N __GFP_FOO bits */
208#define __GFP_BITS_SHIFT (23 + IS_ENABLED(CONFIG_LOCKDEP))
209#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
210
211/*
212 * Useful GFP flag combinations that are commonly used. It is recommended
213 * that subsystems start with one of these combinations and then set/clear
214 * __GFP_FOO flags as necessary.
215 *
216 * GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
217 * watermark is applied to allow access to "atomic reserves"
218 *
219 * GFP_KERNEL is typical for kernel-internal allocations. The caller requires
220 * ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
221 *
222 * GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is
223 * accounted to kmemcg.
224 *
225 * GFP_NOWAIT is for kernel allocations that should not stall for direct
226 * reclaim, start physical IO or use any filesystem callback.
227 *
228 * GFP_NOIO will use direct reclaim to discard clean pages or slab pages
229 * that do not require the starting of any physical IO.
230 * Please try to avoid using this flag directly and instead use
231 * memalloc_noio_{save,restore} to mark the whole scope which cannot
232 * perform any IO with a short explanation why. All allocation requests
233 * will inherit GFP_NOIO implicitly.
234 *
235 * GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
236 * Please try to avoid using this flag directly and instead use
237 * memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't
238 * recurse into the FS layer with a short explanation why. All allocation
239 * requests will inherit GFP_NOFS implicitly.
240 *
241 * GFP_USER is for userspace allocations that also need to be directly
242 * accessibly by the kernel or hardware. It is typically used by hardware
243 * for buffers that are mapped to userspace (e.g. graphics) that hardware
244 * still must DMA to. cpuset limits are enforced for these allocations.
245 *
246 * GFP_DMA exists for historical reasons and should be avoided where possible.
247 * The flags indicates that the caller requires that the lowest zone be
248 * used (ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
249 * it would require careful auditing as some users really require it and
250 * others use the flag to avoid lowmem reserves in ZONE_DMA and treat the
251 * lowest zone as a type of emergency reserve.
252 *
253 * GFP_DMA32 is similar to GFP_DMA except that the caller requires a 32-bit
254 * address.
255 *
256 * GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
257 * do not need to be directly accessible by the kernel but that cannot
258 * move once in use. An example may be a hardware allocation that maps
259 * data directly into userspace but has no addressing limitations.
260 *
261 * GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
262 * need direct access to but can use kmap() when access is required. They
263 * are expected to be movable via page reclaim or page migration. Typically,
264 * pages on the LRU would also be allocated with GFP_HIGHUSER_MOVABLE.
265 *
266 * GFP_TRANSHUGE and GFP_TRANSHUGE_LIGHT are used for THP allocations. They are
267 * compound allocations that will generally fail quickly if memory is not
268 * available and will not wake kswapd/kcompactd on failure. The _LIGHT
269 * version does not attempt reclaim/compaction at all and is by default used
270 * in page fault path, while the non-light is used by khugepaged.
271 */
272#define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
273#define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
274#define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT)
275#define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
276#define GFP_NOIO (__GFP_RECLAIM)
277#define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
278#define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
279#define GFP_DMA __GFP_DMA
280#define GFP_DMA32 __GFP_DMA32
281#define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
282#define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE)
283#define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
284 __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
285#define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
286
287/* Convert GFP flags to their corresponding migrate type */
288#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
289#define GFP_MOVABLE_SHIFT 3
290
291static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
292{
293 VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
294 BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
295 BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
296
297 if (unlikely(page_group_by_mobility_disabled))
298 return MIGRATE_UNMOVABLE;
299
300 /* Group based on mobility */
301 return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
302}
303#undef GFP_MOVABLE_MASK
304#undef GFP_MOVABLE_SHIFT
305
306static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
307{
308 return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
309}
310
311#ifdef CONFIG_HIGHMEM
312#define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
313#else
314#define OPT_ZONE_HIGHMEM ZONE_NORMAL
315#endif
316
317#ifdef CONFIG_ZONE_DMA
318#define OPT_ZONE_DMA ZONE_DMA
319#else
320#define OPT_ZONE_DMA ZONE_NORMAL
321#endif
322
323#ifdef CONFIG_ZONE_DMA32
324#define OPT_ZONE_DMA32 ZONE_DMA32
325#else
326#define OPT_ZONE_DMA32 ZONE_NORMAL
327#endif
328
329/*
330 * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
331 * zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT
332 * bits long and there are 16 of them to cover all possible combinations of
333 * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
334 *
335 * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
336 * But GFP_MOVABLE is not only a zone specifier but also an allocation
337 * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
338 * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
339 *
340 * bit result
341 * =================
342 * 0x0 => NORMAL
343 * 0x1 => DMA or NORMAL
344 * 0x2 => HIGHMEM or NORMAL
345 * 0x3 => BAD (DMA+HIGHMEM)
346 * 0x4 => DMA32 or NORMAL
347 * 0x5 => BAD (DMA+DMA32)
348 * 0x6 => BAD (HIGHMEM+DMA32)
349 * 0x7 => BAD (HIGHMEM+DMA32+DMA)
350 * 0x8 => NORMAL (MOVABLE+0)
351 * 0x9 => DMA or NORMAL (MOVABLE+DMA)
352 * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
353 * 0xb => BAD (MOVABLE+HIGHMEM+DMA)
354 * 0xc => DMA32 or NORMAL (MOVABLE+DMA32)
355 * 0xd => BAD (MOVABLE+DMA32+DMA)
356 * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
357 * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
358 *
359 * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
360 */
361
362#if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
363/* ZONE_DEVICE is not a valid GFP zone specifier */
364#define GFP_ZONES_SHIFT 2
365#else
366#define GFP_ZONES_SHIFT ZONES_SHIFT
367#endif
368
369#if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
370#error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
371#endif
372
373#define GFP_ZONE_TABLE ( \
374 (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \
375 | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \
376 | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \
377 | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \
378 | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \
379 | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \
380 | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
381 | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\
382)
383
384/*
385 * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
386 * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
387 * entry starting with bit 0. Bit is set if the combination is not
388 * allowed.
389 */
390#define GFP_ZONE_BAD ( \
391 1 << (___GFP_DMA | ___GFP_HIGHMEM) \
392 | 1 << (___GFP_DMA | ___GFP_DMA32) \
393 | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
394 | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
395 | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
396 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
397 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
398 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
399)
400
401static inline enum zone_type gfp_zone(gfp_t flags)
402{
403 enum zone_type z;
404 int bit = (__force int) (flags & GFP_ZONEMASK);
405
406 z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) &
407 ((1 << GFP_ZONES_SHIFT) - 1);
408 VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
409 return z;
410}
411
412/*
413 * There is only one page-allocator function, and two main namespaces to
414 * it. The alloc_page*() variants return 'struct page *' and as such
415 * can allocate highmem pages, the *get*page*() variants return
416 * virtual kernel addresses to the allocated page(s).
417 */
418
419static inline int gfp_zonelist(gfp_t flags)
420{
421#ifdef CONFIG_NUMA
422 if (unlikely(flags & __GFP_THISNODE))
423 return ZONELIST_NOFALLBACK;
424#endif
425 return ZONELIST_FALLBACK;
426}
427
428/*
429 * We get the zone list from the current node and the gfp_mask.
430 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
431 * There are two zonelists per node, one for all zones with memory and
432 * one containing just zones from the node the zonelist belongs to.
433 *
434 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
435 * optimized to &contig_page_data at compile-time.
436 */
437static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
438{
439 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
440}
441
442#ifndef HAVE_ARCH_FREE_PAGE
443static inline void arch_free_page(struct page *page, int order) { }
444#endif
445#ifndef HAVE_ARCH_ALLOC_PAGE
446static inline void arch_alloc_page(struct page *page, int order) { }
447#endif
448
449struct page *
450__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid,
451 nodemask_t *nodemask);
452
453static inline struct page *
454__alloc_pages(gfp_t gfp_mask, unsigned int order, int preferred_nid)
455{
456 return __alloc_pages_nodemask(gfp_mask, order, preferred_nid, NULL);
457}
458
459/*
460 * Allocate pages, preferring the node given as nid. The node must be valid and
461 * online. For more general interface, see alloc_pages_node().
462 */
463static inline struct page *
464__alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
465{
466 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
467 VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid));
468
469 return __alloc_pages(gfp_mask, order, nid);
470}
471
472/*
473 * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
474 * prefer the current CPU's closest node. Otherwise node must be valid and
475 * online.
476 */
477static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
478 unsigned int order)
479{
480 if (nid == NUMA_NO_NODE)
481 nid = numa_mem_id();
482
483 return __alloc_pages_node(nid, gfp_mask, order);
484}
485
486#ifdef CONFIG_NUMA
487extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
488
489static inline struct page *
490alloc_pages(gfp_t gfp_mask, unsigned int order)
491{
492 return alloc_pages_current(gfp_mask, order);
493}
494extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
495 struct vm_area_struct *vma, unsigned long addr,
496 int node, bool hugepage);
497#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
498 alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
499#else
500#define alloc_pages(gfp_mask, order) \
501 alloc_pages_node(numa_node_id(), gfp_mask, order)
502#define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
503 alloc_pages(gfp_mask, order)
504#define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
505 alloc_pages(gfp_mask, order)
506#endif
507#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
508#define alloc_page_vma(gfp_mask, vma, addr) \
509 alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false)
510#define alloc_page_vma_node(gfp_mask, vma, addr, node) \
511 alloc_pages_vma(gfp_mask, 0, vma, addr, node, false)
512
513extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
514extern unsigned long get_zeroed_page(gfp_t gfp_mask);
515
516void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
517void free_pages_exact(void *virt, size_t size);
518void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
519
520#define __get_free_page(gfp_mask) \
521 __get_free_pages((gfp_mask), 0)
522
523#define __get_dma_pages(gfp_mask, order) \
524 __get_free_pages((gfp_mask) | GFP_DMA, (order))
525
526extern void __free_pages(struct page *page, unsigned int order);
527extern void free_pages(unsigned long addr, unsigned int order);
528extern void free_unref_page(struct page *page);
529extern void free_unref_page_list(struct list_head *list);
530
531struct page_frag_cache;
532extern void __page_frag_cache_drain(struct page *page, unsigned int count);
533extern void *page_frag_alloc(struct page_frag_cache *nc,
534 unsigned int fragsz, gfp_t gfp_mask);
535extern void page_frag_free(void *addr);
536
537#define __free_page(page) __free_pages((page), 0)
538#define free_page(addr) free_pages((addr), 0)
539
540void page_alloc_init(void);
541void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
542void drain_all_pages(struct zone *zone);
543void drain_local_pages(struct zone *zone);
544
545void page_alloc_init_late(void);
546
547/*
548 * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
549 * GFP flags are used before interrupts are enabled. Once interrupts are
550 * enabled, it is set to __GFP_BITS_MASK while the system is running. During
551 * hibernation, it is used by PM to avoid I/O during memory allocation while
552 * devices are suspended.
553 */
554extern gfp_t gfp_allowed_mask;
555
556/* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
557bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
558
559extern void pm_restrict_gfp_mask(void);
560extern void pm_restore_gfp_mask(void);
561
562#ifdef CONFIG_PM_SLEEP
563extern bool pm_suspended_storage(void);
564#else
565static inline bool pm_suspended_storage(void)
566{
567 return false;
568}
569#endif /* CONFIG_PM_SLEEP */
570
571#if (defined(CONFIG_MEMORY_ISOLATION) && defined(CONFIG_COMPACTION)) || defined(CONFIG_CMA)
572/* The below functions must be run on a range from a single zone. */
573extern int alloc_contig_range(unsigned long start, unsigned long end,
574 unsigned migratetype, gfp_t gfp_mask);
575extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
576#endif
577
578#ifdef CONFIG_CMA
579/* CMA stuff */
580extern void init_cma_reserved_pageblock(struct page *page);
581#endif
582
583#endif /* __LINUX_GFP_H */
584