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
11 struct 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_ZERO 0x100u
28 #define ___GFP_ATOMIC 0x200u
29 #define ___GFP_DIRECT_RECLAIM 0x400u
30 #define ___GFP_KSWAPD_RECLAIM 0x800u
31 #define ___GFP_WRITE 0x1000u
32 #define ___GFP_NOWARN 0x2000u
33 #define ___GFP_RETRY_MAYFAIL 0x4000u
34 #define ___GFP_NOFAIL 0x8000u
35 #define ___GFP_NORETRY 0x10000u
36 #define ___GFP_MEMALLOC 0x20000u
37 #define ___GFP_COMP 0x40000u
38 #define ___GFP_NOMEMALLOC 0x80000u
39 #define ___GFP_HARDWALL 0x100000u
40 #define ___GFP_THISNODE 0x200000u
41 #define ___GFP_ACCOUNT 0x400000u
42 #define ___GFP_ZEROTAGS 0x800000u
43 #define ___GFP_SKIP_KASAN_POISON 0x1000000u
44 #ifdef CONFIG_CMA
45 #define ___GFP_CMA 0x2000000u
46 #else
47 #define ___GFP_CMA 0
48 #endif
49 #ifdef CONFIG_LOCKDEP
50 #ifdef CONFIG_CMA
51 #define ___GFP_NOLOCKDEP 0x4000000u
52 #else
53 #define ___GFP_NOLOCKDEP 0x2000000u
54 #endif
55 #else
56 #define ___GFP_NOLOCKDEP 0
57 #endif
58
59 /* If the above are modified, __GFP_BITS_SHIFT may need updating */
60
61 /*
62 * Physical address zone modifiers (see linux/mmzone.h - low four bits)
63 *
64 * Do not put any conditional on these. If necessary modify the definitions
65 * without the underscores and use them consistently. The definitions here may
66 * be used in bit comparisons.
67 */
68 #define __GFP_DMA ((__force gfp_t)___GFP_DMA)
69 #define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
70 #define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
71 #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
72 #define __GFP_CMA ((__force gfp_t)___GFP_CMA)
73 #define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
74
75 /**
76 * DOC: Page mobility and placement hints
77 *
78 * Page mobility and placement hints
79 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
80 *
81 * These flags provide hints about how mobile the page is. Pages with similar
82 * mobility are placed within the same pageblocks to minimise problems due
83 * to external fragmentation.
84 *
85 * %__GFP_MOVABLE (also a zone modifier) indicates that the page can be
86 * moved by page migration during memory compaction or can be reclaimed.
87 *
88 * %__GFP_RECLAIMABLE is used for slab allocations that specify
89 * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
90 *
91 * %__GFP_WRITE indicates the caller intends to dirty the page. Where possible,
92 * these pages will be spread between local zones to avoid all the dirty
93 * pages being in one zone (fair zone allocation policy).
94 *
95 * %__GFP_HARDWALL enforces the cpuset memory allocation policy.
96 *
97 * %__GFP_THISNODE forces the allocation to be satisfied from the requested
98 * node with no fallbacks or placement policy enforcements.
99 *
100 * %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
101 */
102 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
103 #define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
104 #define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
105 #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
106 #define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT)
107
108 /**
109 * DOC: Watermark modifiers
110 *
111 * Watermark modifiers -- controls access to emergency reserves
112 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
113 *
114 * %__GFP_HIGH indicates that the caller is high-priority and that granting
115 * the request is necessary before the system can make forward progress.
116 * For example, creating an IO context to clean pages.
117 *
118 * %__GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
119 * high priority. Users are typically interrupt handlers. This may be
120 * used in conjunction with %__GFP_HIGH
121 *
122 * %__GFP_MEMALLOC allows access to all memory. This should only be used when
123 * the caller guarantees the allocation will allow more memory to be freed
124 * very shortly e.g. process exiting or swapping. Users either should
125 * be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
126 * Users of this flag have to be extremely careful to not deplete the reserve
127 * completely and implement a throttling mechanism which controls the
128 * consumption of the reserve based on the amount of freed memory.
129 * Usage of a pre-allocated pool (e.g. mempool) should be always considered
130 * before using this flag.
131 *
132 * %__GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
133 * This takes precedence over the %__GFP_MEMALLOC flag if both are set.
134 */
135 #define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
136 #define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
137 #define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
138 #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
139
140 /**
141 * DOC: Reclaim modifiers
142 *
143 * Reclaim modifiers
144 * ~~~~~~~~~~~~~~~~~
145 * Please note that all the following flags are only applicable to sleepable
146 * allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them).
147 *
148 * %__GFP_IO can start physical IO.
149 *
150 * %__GFP_FS can call down to the low-level FS. Clearing the flag avoids the
151 * allocator recursing into the filesystem which might already be holding
152 * locks.
153 *
154 * %__GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
155 * This flag can be cleared to avoid unnecessary delays when a fallback
156 * option is available.
157 *
158 * %__GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
159 * the low watermark is reached and have it reclaim pages until the high
160 * watermark is reached. A caller may wish to clear this flag when fallback
161 * options are available and the reclaim is likely to disrupt the system. The
162 * canonical example is THP allocation where a fallback is cheap but
163 * reclaim/compaction may cause indirect stalls.
164 *
165 * %__GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
166 *
167 * The default allocator behavior depends on the request size. We have a concept
168 * of so called costly allocations (with order > %PAGE_ALLOC_COSTLY_ORDER).
169 * !costly allocations are too essential to fail so they are implicitly
170 * non-failing by default (with some exceptions like OOM victims might fail so
171 * the caller still has to check for failures) while costly requests try to be
172 * not disruptive and back off even without invoking the OOM killer.
173 * The following three modifiers might be used to override some of these
174 * implicit rules
175 *
176 * %__GFP_NORETRY: The VM implementation will try only very lightweight
177 * memory direct reclaim to get some memory under memory pressure (thus
178 * it can sleep). It will avoid disruptive actions like OOM killer. The
179 * caller must handle the failure which is quite likely to happen under
180 * heavy memory pressure. The flag is suitable when failure can easily be
181 * handled at small cost, such as reduced throughput
182 *
183 * %__GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim
184 * procedures that have previously failed if there is some indication
185 * that progress has been made else where. It can wait for other
186 * tasks to attempt high level approaches to freeing memory such as
187 * compaction (which removes fragmentation) and page-out.
188 * There is still a definite limit to the number of retries, but it is
189 * a larger limit than with %__GFP_NORETRY.
190 * Allocations with this flag may fail, but only when there is
191 * genuinely little unused memory. While these allocations do not
192 * directly trigger the OOM killer, their failure indicates that
193 * the system is likely to need to use the OOM killer soon. The
194 * caller must handle failure, but can reasonably do so by failing
195 * a higher-level request, or completing it only in a much less
196 * efficient manner.
197 * If the allocation does fail, and the caller is in a position to
198 * free some non-essential memory, doing so could benefit the system
199 * as a whole.
200 *
201 * %__GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
202 * cannot handle allocation failures. The allocation could block
203 * indefinitely but will never return with failure. Testing for
204 * failure is pointless.
205 * New users should be evaluated carefully (and the flag should be
206 * used only when there is no reasonable failure policy) but it is
207 * definitely preferable to use the flag rather than opencode endless
208 * loop around allocator.
209 * Using this flag for costly allocations is _highly_ discouraged.
210 */
211 #define __GFP_IO ((__force gfp_t)___GFP_IO)
212 #define __GFP_FS ((__force gfp_t)___GFP_FS)
213 #define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
214 #define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
215 #define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
216 #define __GFP_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL)
217 #define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
218 #define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
219
220 /**
221 * DOC: Action modifiers
222 *
223 * Action modifiers
224 * ~~~~~~~~~~~~~~~~
225 *
226 * %__GFP_NOWARN suppresses allocation failure reports.
227 *
228 * %__GFP_COMP address compound page metadata.
229 *
230 * %__GFP_ZERO returns a zeroed page on success.
231 *
232 * %__GFP_ZEROTAGS returns a page with zeroed memory tags on success, if
233 * __GFP_ZERO is set.
234 *
235 * %__GFP_SKIP_KASAN_POISON returns a page which does not need to be poisoned
236 * on deallocation. Typically used for userspace pages. Currently only has an
237 * effect in HW tags mode.
238 */
239 #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
240 #define __GFP_COMP ((__force gfp_t)___GFP_COMP)
241 #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
242 #define __GFP_ZEROTAGS ((__force gfp_t)___GFP_ZEROTAGS)
243 #define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON)
244
245 /* Disable lockdep for GFP context tracking */
246 #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
247
248 /* Room for N __GFP_FOO bits */
249 #ifdef CONFIG_CMA
250 #define __GFP_BITS_SHIFT (26 + IS_ENABLED(CONFIG_LOCKDEP))
251 #else
252 #define __GFP_BITS_SHIFT (25 + IS_ENABLED(CONFIG_LOCKDEP))
253 #endif
254 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
255
256 /**
257 * DOC: Useful GFP flag combinations
258 *
259 * Useful GFP flag combinations
260 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
261 *
262 * Useful GFP flag combinations that are commonly used. It is recommended
263 * that subsystems start with one of these combinations and then set/clear
264 * %__GFP_FOO flags as necessary.
265 *
266 * %GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
267 * watermark is applied to allow access to "atomic reserves".
268 * The current implementation doesn't support NMI and few other strict
269 * non-preemptive contexts (e.g. raw_spin_lock). The same applies to %GFP_NOWAIT.
270 *
271 * %GFP_KERNEL is typical for kernel-internal allocations. The caller requires
272 * %ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
273 *
274 * %GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is
275 * accounted to kmemcg.
276 *
277 * %GFP_NOWAIT is for kernel allocations that should not stall for direct
278 * reclaim, start physical IO or use any filesystem callback.
279 *
280 * %GFP_NOIO will use direct reclaim to discard clean pages or slab pages
281 * that do not require the starting of any physical IO.
282 * Please try to avoid using this flag directly and instead use
283 * memalloc_noio_{save,restore} to mark the whole scope which cannot
284 * perform any IO with a short explanation why. All allocation requests
285 * will inherit GFP_NOIO implicitly.
286 *
287 * %GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
288 * Please try to avoid using this flag directly and instead use
289 * memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't
290 * recurse into the FS layer with a short explanation why. All allocation
291 * requests will inherit GFP_NOFS implicitly.
292 *
293 * %GFP_USER is for userspace allocations that also need to be directly
294 * accessibly by the kernel or hardware. It is typically used by hardware
295 * for buffers that are mapped to userspace (e.g. graphics) that hardware
296 * still must DMA to. cpuset limits are enforced for these allocations.
297 *
298 * %GFP_DMA exists for historical reasons and should be avoided where possible.
299 * The flags indicates that the caller requires that the lowest zone be
300 * used (%ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
301 * it would require careful auditing as some users really require it and
302 * others use the flag to avoid lowmem reserves in %ZONE_DMA and treat the
303 * lowest zone as a type of emergency reserve.
304 *
305 * %GFP_DMA32 is similar to %GFP_DMA except that the caller requires a 32-bit
306 * address.
307 *
308 * %GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
309 * do not need to be directly accessible by the kernel but that cannot
310 * move once in use. An example may be a hardware allocation that maps
311 * data directly into userspace but has no addressing limitations.
312 *
313 * %GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
314 * need direct access to but can use kmap() when access is required. They
315 * are expected to be movable via page reclaim or page migration. Typically,
316 * pages on the LRU would also be allocated with %GFP_HIGHUSER_MOVABLE.
317 *
318 * %GFP_TRANSHUGE and %GFP_TRANSHUGE_LIGHT are used for THP allocations. They
319 * are compound allocations that will generally fail quickly if memory is not
320 * available and will not wake kswapd/kcompactd on failure. The _LIGHT
321 * version does not attempt reclaim/compaction at all and is by default used
322 * in page fault path, while the non-light is used by khugepaged.
323 */
324 #define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
325 #define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
326 #define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT)
327 #define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
328 #define GFP_NOIO (__GFP_RECLAIM)
329 #define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
330 #define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
331 #define GFP_DMA __GFP_DMA
332 #define GFP_DMA32 __GFP_DMA32
333 #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
334 #define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE | \
335 __GFP_SKIP_KASAN_POISON)
336 #define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
337 __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
338 #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
339
340 /* Convert GFP flags to their corresponding migrate type */
341 #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
342 #define GFP_MOVABLE_SHIFT 3
343
gfp_migratetype(const gfp_t gfp_flags)344 static inline int gfp_migratetype(const gfp_t gfp_flags)
345 {
346 VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
347 BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
348 BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
349
350 if (unlikely(page_group_by_mobility_disabled))
351 return MIGRATE_UNMOVABLE;
352
353 /* Group based on mobility */
354 return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
355 }
356 #undef GFP_MOVABLE_MASK
357 #undef GFP_MOVABLE_SHIFT
358
gfpflags_allow_blocking(const gfp_t gfp_flags)359 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
360 {
361 return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
362 }
363
364 /**
365 * gfpflags_normal_context - is gfp_flags a normal sleepable context?
366 * @gfp_flags: gfp_flags to test
367 *
368 * Test whether @gfp_flags indicates that the allocation is from the
369 * %current context and allowed to sleep.
370 *
371 * An allocation being allowed to block doesn't mean it owns the %current
372 * context. When direct reclaim path tries to allocate memory, the
373 * allocation context is nested inside whatever %current was doing at the
374 * time of the original allocation. The nested allocation may be allowed
375 * to block but modifying anything %current owns can corrupt the outer
376 * context's expectations.
377 *
378 * %true result from this function indicates that the allocation context
379 * can sleep and use anything that's associated with %current.
380 */
gfpflags_normal_context(const gfp_t gfp_flags)381 static inline bool gfpflags_normal_context(const gfp_t gfp_flags)
382 {
383 return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) ==
384 __GFP_DIRECT_RECLAIM;
385 }
386
387 #ifdef CONFIG_HIGHMEM
388 #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
389 #else
390 #define OPT_ZONE_HIGHMEM ZONE_NORMAL
391 #endif
392
393 #ifdef CONFIG_ZONE_DMA
394 #define OPT_ZONE_DMA ZONE_DMA
395 #else
396 #define OPT_ZONE_DMA ZONE_NORMAL
397 #endif
398
399 #ifdef CONFIG_ZONE_DMA32
400 #define OPT_ZONE_DMA32 ZONE_DMA32
401 #else
402 #define OPT_ZONE_DMA32 ZONE_NORMAL
403 #endif
404
405 /*
406 * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
407 * zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT
408 * bits long and there are 16 of them to cover all possible combinations of
409 * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
410 *
411 * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
412 * But GFP_MOVABLE is not only a zone specifier but also an allocation
413 * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
414 * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
415 *
416 * bit result
417 * =================
418 * 0x0 => NORMAL
419 * 0x1 => DMA or NORMAL
420 * 0x2 => HIGHMEM or NORMAL
421 * 0x3 => BAD (DMA+HIGHMEM)
422 * 0x4 => DMA32 or NORMAL
423 * 0x5 => BAD (DMA+DMA32)
424 * 0x6 => BAD (HIGHMEM+DMA32)
425 * 0x7 => BAD (HIGHMEM+DMA32+DMA)
426 * 0x8 => NORMAL (MOVABLE+0)
427 * 0x9 => DMA or NORMAL (MOVABLE+DMA)
428 * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
429 * 0xb => BAD (MOVABLE+HIGHMEM+DMA)
430 * 0xc => DMA32 or NORMAL (MOVABLE+DMA32)
431 * 0xd => BAD (MOVABLE+DMA32+DMA)
432 * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
433 * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
434 *
435 * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
436 */
437
438 #if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
439 /* ZONE_DEVICE is not a valid GFP zone specifier */
440 #define GFP_ZONES_SHIFT 2
441 #else
442 #define GFP_ZONES_SHIFT ZONES_SHIFT
443 #endif
444
445 #if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
446 #error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
447 #endif
448
449 #define GFP_ZONE_TABLE ( \
450 (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \
451 | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \
452 | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \
453 | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \
454 | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \
455 | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \
456 | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
457 | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\
458 )
459
460 /*
461 * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
462 * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
463 * entry starting with bit 0. Bit is set if the combination is not
464 * allowed.
465 */
466 #define GFP_ZONE_BAD ( \
467 1 << (___GFP_DMA | ___GFP_HIGHMEM) \
468 | 1 << (___GFP_DMA | ___GFP_DMA32) \
469 | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
470 | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
471 | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
472 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
473 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
474 | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
475 )
476
477 enum zone_type gfp_zone(gfp_t flags);
478
479 /*
480 * There is only one page-allocator function, and two main namespaces to
481 * it. The alloc_page*() variants return 'struct page *' and as such
482 * can allocate highmem pages, the *get*page*() variants return
483 * virtual kernel addresses to the allocated page(s).
484 */
485
gfp_zonelist(gfp_t flags)486 static inline int gfp_zonelist(gfp_t flags)
487 {
488 #ifdef CONFIG_NUMA
489 if (unlikely(flags & __GFP_THISNODE))
490 return ZONELIST_NOFALLBACK;
491 #endif
492 return ZONELIST_FALLBACK;
493 }
494
495 /*
496 * We get the zone list from the current node and the gfp_mask.
497 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
498 * There are two zonelists per node, one for all zones with memory and
499 * one containing just zones from the node the zonelist belongs to.
500 *
501 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
502 * optimized to &contig_page_data at compile-time.
503 */
node_zonelist(int nid,gfp_t flags)504 static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
505 {
506 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
507 }
508
509 #ifndef HAVE_ARCH_FREE_PAGE
arch_free_page(struct page * page,int order)510 static inline void arch_free_page(struct page *page, int order) { }
511 #endif
512 #ifndef HAVE_ARCH_ALLOC_PAGE
arch_alloc_page(struct page * page,int order)513 static inline void arch_alloc_page(struct page *page, int order) { }
514 #endif
515 #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE
arch_make_page_accessible(struct page * page)516 static inline int arch_make_page_accessible(struct page *page)
517 {
518 return 0;
519 }
520 #endif
521
522 struct page *
523 __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid,
524 nodemask_t *nodemask);
525
526 static inline struct page *
__alloc_pages(gfp_t gfp_mask,unsigned int order,int preferred_nid)527 __alloc_pages(gfp_t gfp_mask, unsigned int order, int preferred_nid)
528 {
529 return __alloc_pages_nodemask(gfp_mask, order, preferred_nid, NULL);
530 }
531
532 /*
533 * Allocate pages, preferring the node given as nid. The node must be valid and
534 * online. For more general interface, see alloc_pages_node().
535 */
536 static inline struct page *
__alloc_pages_node(int nid,gfp_t gfp_mask,unsigned int order)537 __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
538 {
539 VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
540 VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid));
541
542 return __alloc_pages(gfp_mask, order, nid);
543 }
544
545 /*
546 * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
547 * prefer the current CPU's closest node. Otherwise node must be valid and
548 * online.
549 */
alloc_pages_node(int nid,gfp_t gfp_mask,unsigned int order)550 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
551 unsigned int order)
552 {
553 if (nid == NUMA_NO_NODE)
554 nid = numa_mem_id();
555
556 return __alloc_pages_node(nid, gfp_mask, order);
557 }
558
559 #ifdef CONFIG_NUMA
560 extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
561
562 static inline struct page *
alloc_pages(gfp_t gfp_mask,unsigned int order)563 alloc_pages(gfp_t gfp_mask, unsigned int order)
564 {
565 return alloc_pages_current(gfp_mask, order);
566 }
567 extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
568 struct vm_area_struct *vma, unsigned long addr,
569 int node, bool hugepage);
570 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
571 alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
572 #else
alloc_pages(gfp_t gfp_mask,unsigned int order)573 static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order)
574 {
575 return alloc_pages_node(numa_node_id(), gfp_mask, order);
576 }
577 #define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
578 alloc_pages(gfp_mask, order)
579 #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
580 alloc_pages(gfp_mask, order)
581 #endif
582 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
583 #define alloc_page_vma(gfp_mask, vma, addr) \
584 alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false)
585
586 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
587 extern unsigned long get_zeroed_page(gfp_t gfp_mask);
588
589 void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
590 void free_pages_exact(void *virt, size_t size);
591 void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
592
593 #define __get_free_page(gfp_mask) \
594 __get_free_pages((gfp_mask), 0)
595
596 #define __get_dma_pages(gfp_mask, order) \
597 __get_free_pages((gfp_mask) | GFP_DMA, (order))
598
599 extern void __free_pages(struct page *page, unsigned int order);
600 extern void free_pages(unsigned long addr, unsigned int order);
601 extern void free_unref_page(struct page *page);
602 extern void free_unref_page_list(struct list_head *list);
603
604 struct page_frag_cache;
605 extern void __page_frag_cache_drain(struct page *page, unsigned int count);
606 extern void *page_frag_alloc(struct page_frag_cache *nc,
607 unsigned int fragsz, gfp_t gfp_mask);
608 extern void page_frag_free(void *addr);
609
610 #define __free_page(page) __free_pages((page), 0)
611 #define free_page(addr) free_pages((addr), 0)
612
613 void page_alloc_init(void);
614 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
615 void drain_all_pages(struct zone *zone);
616 void drain_local_pages(struct zone *zone);
617
618 void page_alloc_init_late(void);
619
620 /*
621 * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
622 * GFP flags are used before interrupts are enabled. Once interrupts are
623 * enabled, it is set to __GFP_BITS_MASK while the system is running. During
624 * hibernation, it is used by PM to avoid I/O during memory allocation while
625 * devices are suspended.
626 */
627 extern gfp_t gfp_allowed_mask;
628
629 /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
630 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
631
632 extern void pm_restrict_gfp_mask(void);
633 extern void pm_restore_gfp_mask(void);
634
635 #ifdef CONFIG_PM_SLEEP
636 extern bool pm_suspended_storage(void);
637 #else
pm_suspended_storage(void)638 static inline bool pm_suspended_storage(void)
639 {
640 return false;
641 }
642 #endif /* CONFIG_PM_SLEEP */
643
644 #ifdef CONFIG_CONTIG_ALLOC
645 extern unsigned long pfn_max_align_up(unsigned long pfn);
646
647 #define ACR_ERR_ISOLATE (1 << 0)
648 #define ACR_ERR_MIGRATE (1 << 1)
649 #define ACR_ERR_TEST (1 << 2)
650
651 struct acr_info {
652 unsigned long nr_mapped;
653 unsigned long nr_migrated;
654 unsigned long nr_reclaimed;
655 unsigned int err;
656 unsigned long failed_pfn;
657 };
658
659 /* The below functions must be run on a range from a single zone. */
660 extern int alloc_contig_range(unsigned long start, unsigned long end,
661 unsigned migratetype, gfp_t gfp_mask,
662 struct acr_info *info);
663 extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
664 int nid, nodemask_t *nodemask);
665 #endif
666 void free_contig_range(unsigned long pfn, unsigned int nr_pages);
667
668 #ifdef CONFIG_CMA
669 /* CMA stuff */
670 extern void init_cma_reserved_pageblock(struct page *page);
671 #endif
672
673 #endif /* __LINUX_GFP_H */
674