Line data Source code
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 : /* The typedef is in types.h but we want the documentation here */
12 : #if 0
13 : /**
14 : * typedef gfp_t - Memory allocation flags.
15 : *
16 : * GFP flags are commonly used throughout Linux to indicate how memory
17 : * should be allocated. The GFP acronym stands for get_free_pages(),
18 : * the underlying memory allocation function. Not every GFP flag is
19 : * supported by every function which may allocate memory. Most users
20 : * will want to use a plain ``GFP_KERNEL``.
21 : */
22 : typedef unsigned int __bitwise gfp_t;
23 : #endif
24 :
25 : struct vm_area_struct;
26 :
27 : /*
28 : * In case of changes, please don't forget to update
29 : * include/trace/events/mmflags.h and tools/perf/builtin-kmem.c
30 : */
31 :
32 : /* Plain integer GFP bitmasks. Do not use this directly. */
33 : #define ___GFP_DMA 0x01u
34 : #define ___GFP_HIGHMEM 0x02u
35 : #define ___GFP_DMA32 0x04u
36 : #define ___GFP_MOVABLE 0x08u
37 : #define ___GFP_RECLAIMABLE 0x10u
38 : #define ___GFP_HIGH 0x20u
39 : #define ___GFP_IO 0x40u
40 : #define ___GFP_FS 0x80u
41 : #define ___GFP_ZERO 0x100u
42 : #define ___GFP_ATOMIC 0x200u
43 : #define ___GFP_DIRECT_RECLAIM 0x400u
44 : #define ___GFP_KSWAPD_RECLAIM 0x800u
45 : #define ___GFP_WRITE 0x1000u
46 : #define ___GFP_NOWARN 0x2000u
47 : #define ___GFP_RETRY_MAYFAIL 0x4000u
48 : #define ___GFP_NOFAIL 0x8000u
49 : #define ___GFP_NORETRY 0x10000u
50 : #define ___GFP_MEMALLOC 0x20000u
51 : #define ___GFP_COMP 0x40000u
52 : #define ___GFP_NOMEMALLOC 0x80000u
53 : #define ___GFP_HARDWALL 0x100000u
54 : #define ___GFP_THISNODE 0x200000u
55 : #define ___GFP_ACCOUNT 0x400000u
56 : #ifdef CONFIG_LOCKDEP
57 : #define ___GFP_NOLOCKDEP 0x800000u
58 : #else
59 : #define ___GFP_NOLOCKDEP 0
60 : #endif
61 : /* If the above are modified, __GFP_BITS_SHIFT may need updating */
62 :
63 : /*
64 : * Physical address zone modifiers (see linux/mmzone.h - low four bits)
65 : *
66 : * Do not put any conditional on these. If necessary modify the definitions
67 : * without the underscores and use them consistently. The definitions here may
68 : * be used in bit comparisons.
69 : */
70 : #define __GFP_DMA ((__force gfp_t)___GFP_DMA)
71 : #define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
72 : #define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
73 : #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
74 : #define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
75 :
76 : /**
77 : * DOC: Page mobility and placement hints
78 : *
79 : * Page mobility and placement hints
80 : * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
81 : *
82 : * These flags provide hints about how mobile the page is. Pages with similar
83 : * mobility are placed within the same pageblocks to minimise problems due
84 : * to external fragmentation.
85 : *
86 : * %__GFP_MOVABLE (also a zone modifier) indicates that the page can be
87 : * moved by page migration during memory compaction or can be reclaimed.
88 : *
89 : * %__GFP_RECLAIMABLE is used for slab allocations that specify
90 : * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
91 : *
92 : * %__GFP_WRITE indicates the caller intends to dirty the page. Where possible,
93 : * these pages will be spread between local zones to avoid all the dirty
94 : * pages being in one zone (fair zone allocation policy).
95 : *
96 : * %__GFP_HARDWALL enforces the cpuset memory allocation policy.
97 : *
98 : * %__GFP_THISNODE forces the allocation to be satisfied from the requested
99 : * node with no fallbacks or placement policy enforcements.
100 : *
101 : * %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
102 : */
103 : #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
104 : #define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
105 : #define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
106 : #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
107 : #define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT)
108 :
109 : /**
110 : * DOC: Watermark modifiers
111 : *
112 : * Watermark modifiers -- controls access to emergency reserves
113 : * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
114 : *
115 : * %__GFP_HIGH indicates that the caller is high-priority and that granting
116 : * the request is necessary before the system can make forward progress.
117 : * For example, creating an IO context to clean pages.
118 : *
119 : * %__GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
120 : * high priority. Users are typically interrupt handlers. This may be
121 : * used in conjunction with %__GFP_HIGH
122 : *
123 : * %__GFP_MEMALLOC allows access to all memory. This should only be used when
124 : * the caller guarantees the allocation will allow more memory to be freed
125 : * very shortly e.g. process exiting or swapping. Users either should
126 : * be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
127 : * Users of this flag have to be extremely careful to not deplete the reserve
128 : * completely and implement a throttling mechanism which controls the
129 : * consumption of the reserve based on the amount of freed memory.
130 : * Usage of a pre-allocated pool (e.g. mempool) should be always considered
131 : * before using this flag.
132 : *
133 : * %__GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
134 : * This takes precedence over the %__GFP_MEMALLOC flag if both are set.
135 : */
136 : #define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
137 : #define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
138 : #define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
139 : #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
140 :
141 : /**
142 : * DOC: Reclaim modifiers
143 : *
144 : * Reclaim modifiers
145 : * ~~~~~~~~~~~~~~~~~
146 : * Please note that all the following flags are only applicable to sleepable
147 : * allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them).
148 : *
149 : * %__GFP_IO can start physical IO.
150 : *
151 : * %__GFP_FS can call down to the low-level FS. Clearing the flag avoids the
152 : * allocator recursing into the filesystem which might already be holding
153 : * locks.
154 : *
155 : * %__GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
156 : * This flag can be cleared to avoid unnecessary delays when a fallback
157 : * option is available.
158 : *
159 : * %__GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
160 : * the low watermark is reached and have it reclaim pages until the high
161 : * watermark is reached. A caller may wish to clear this flag when fallback
162 : * options are available and the reclaim is likely to disrupt the system. The
163 : * canonical example is THP allocation where a fallback is cheap but
164 : * reclaim/compaction may cause indirect stalls.
165 : *
166 : * %__GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
167 : *
168 : * The default allocator behavior depends on the request size. We have a concept
169 : * of so called costly allocations (with order > %PAGE_ALLOC_COSTLY_ORDER).
170 : * !costly allocations are too essential to fail so they are implicitly
171 : * non-failing by default (with some exceptions like OOM victims might fail so
172 : * the caller still has to check for failures) while costly requests try to be
173 : * not disruptive and back off even without invoking the OOM killer.
174 : * The following three modifiers might be used to override some of these
175 : * implicit rules
176 : *
177 : * %__GFP_NORETRY: The VM implementation will try only very lightweight
178 : * memory direct reclaim to get some memory under memory pressure (thus
179 : * it can sleep). It will avoid disruptive actions like OOM killer. The
180 : * caller must handle the failure which is quite likely to happen under
181 : * heavy memory pressure. The flag is suitable when failure can easily be
182 : * handled at small cost, such as reduced throughput
183 : *
184 : * %__GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim
185 : * procedures that have previously failed if there is some indication
186 : * that progress has been made else where. It can wait for other
187 : * tasks to attempt high level approaches to freeing memory such as
188 : * compaction (which removes fragmentation) and page-out.
189 : * There is still a definite limit to the number of retries, but it is
190 : * a larger limit than with %__GFP_NORETRY.
191 : * Allocations with this flag may fail, but only when there is
192 : * genuinely little unused memory. While these allocations do not
193 : * directly trigger the OOM killer, their failure indicates that
194 : * the system is likely to need to use the OOM killer soon. The
195 : * caller must handle failure, but can reasonably do so by failing
196 : * a higher-level request, or completing it only in a much less
197 : * efficient manner.
198 : * If the allocation does fail, and the caller is in a position to
199 : * free some non-essential memory, doing so could benefit the system
200 : * as a whole.
201 : *
202 : * %__GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
203 : * cannot handle allocation failures. The allocation could block
204 : * indefinitely but will never return with failure. Testing for
205 : * failure is pointless.
206 : * New users should be evaluated carefully (and the flag should be
207 : * used only when there is no reasonable failure policy) but it is
208 : * definitely preferable to use the flag rather than opencode endless
209 : * loop around allocator.
210 : * Using this flag for costly allocations is _highly_ discouraged.
211 : */
212 : #define __GFP_IO ((__force gfp_t)___GFP_IO)
213 : #define __GFP_FS ((__force gfp_t)___GFP_FS)
214 : #define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
215 : #define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
216 : #define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
217 : #define __GFP_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL)
218 : #define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
219 : #define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
220 :
221 : /**
222 : * DOC: Action modifiers
223 : *
224 : * Action modifiers
225 : * ~~~~~~~~~~~~~~~~
226 : *
227 : * %__GFP_NOWARN suppresses allocation failure reports.
228 : *
229 : * %__GFP_COMP address compound page metadata.
230 : *
231 : * %__GFP_ZERO returns a zeroed page on success.
232 : */
233 : #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
234 : #define __GFP_COMP ((__force gfp_t)___GFP_COMP)
235 : #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
236 :
237 : /* Disable lockdep for GFP context tracking */
238 : #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
239 :
240 : /* Room for N __GFP_FOO bits */
241 : #define __GFP_BITS_SHIFT (23 + IS_ENABLED(CONFIG_LOCKDEP))
242 : #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
243 :
244 : /**
245 : * DOC: Useful GFP flag combinations
246 : *
247 : * Useful GFP flag combinations
248 : * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
249 : *
250 : * Useful GFP flag combinations that are commonly used. It is recommended
251 : * that subsystems start with one of these combinations and then set/clear
252 : * %__GFP_FOO flags as necessary.
253 : *
254 : * %GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
255 : * watermark is applied to allow access to "atomic reserves".
256 : * The current implementation doesn't support NMI and few other strict
257 : * non-preemptive contexts (e.g. raw_spin_lock). The same applies to %GFP_NOWAIT.
258 : *
259 : * %GFP_KERNEL is typical for kernel-internal allocations. The caller requires
260 : * %ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
261 : *
262 : * %GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is
263 : * accounted to kmemcg.
264 : *
265 : * %GFP_NOWAIT is for kernel allocations that should not stall for direct
266 : * reclaim, start physical IO or use any filesystem callback.
267 : *
268 : * %GFP_NOIO will use direct reclaim to discard clean pages or slab pages
269 : * that do not require the starting of any physical IO.
270 : * Please try to avoid using this flag directly and instead use
271 : * memalloc_noio_{save,restore} to mark the whole scope which cannot
272 : * perform any IO with a short explanation why. All allocation requests
273 : * will inherit GFP_NOIO implicitly.
274 : *
275 : * %GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
276 : * Please try to avoid using this flag directly and instead use
277 : * memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't
278 : * recurse into the FS layer with a short explanation why. All allocation
279 : * requests will inherit GFP_NOFS implicitly.
280 : *
281 : * %GFP_USER is for userspace allocations that also need to be directly
282 : * accessibly by the kernel or hardware. It is typically used by hardware
283 : * for buffers that are mapped to userspace (e.g. graphics) that hardware
284 : * still must DMA to. cpuset limits are enforced for these allocations.
285 : *
286 : * %GFP_DMA exists for historical reasons and should be avoided where possible.
287 : * The flags indicates that the caller requires that the lowest zone be
288 : * used (%ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
289 : * it would require careful auditing as some users really require it and
290 : * others use the flag to avoid lowmem reserves in %ZONE_DMA and treat the
291 : * lowest zone as a type of emergency reserve.
292 : *
293 : * %GFP_DMA32 is similar to %GFP_DMA except that the caller requires a 32-bit
294 : * address.
295 : *
296 : * %GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
297 : * do not need to be directly accessible by the kernel but that cannot
298 : * move once in use. An example may be a hardware allocation that maps
299 : * data directly into userspace but has no addressing limitations.
300 : *
301 : * %GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
302 : * need direct access to but can use kmap() when access is required. They
303 : * are expected to be movable via page reclaim or page migration. Typically,
304 : * pages on the LRU would also be allocated with %GFP_HIGHUSER_MOVABLE.
305 : *
306 : * %GFP_TRANSHUGE and %GFP_TRANSHUGE_LIGHT are used for THP allocations. They
307 : * are compound allocations that will generally fail quickly if memory is not
308 : * available and will not wake kswapd/kcompactd on failure. The _LIGHT
309 : * version does not attempt reclaim/compaction at all and is by default used
310 : * in page fault path, while the non-light is used by khugepaged.
311 : */
312 : #define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
313 : #define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
314 : #define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT)
315 : #define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
316 : #define GFP_NOIO (__GFP_RECLAIM)
317 : #define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
318 : #define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
319 : #define GFP_DMA __GFP_DMA
320 : #define GFP_DMA32 __GFP_DMA32
321 : #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
322 : #define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE)
323 : #define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
324 : __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
325 : #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
326 :
327 : /* Convert GFP flags to their corresponding migrate type */
328 : #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
329 : #define GFP_MOVABLE_SHIFT 3
330 :
331 193142 : static inline int gfp_migratetype(const gfp_t gfp_flags)
332 : {
333 193142 : VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
334 193142 : BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
335 193142 : BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
336 :
337 193142 : if (unlikely(page_group_by_mobility_disabled))
338 : return MIGRATE_UNMOVABLE;
339 :
340 : /* Group based on mobility */
341 193142 : return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
342 : }
343 : #undef GFP_MOVABLE_MASK
344 : #undef GFP_MOVABLE_SHIFT
345 :
346 3111872 : static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
347 : {
348 3111872 : return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
349 : }
350 :
351 : /**
352 : * gfpflags_normal_context - is gfp_flags a normal sleepable context?
353 : * @gfp_flags: gfp_flags to test
354 : *
355 : * Test whether @gfp_flags indicates that the allocation is from the
356 : * %current context and allowed to sleep.
357 : *
358 : * An allocation being allowed to block doesn't mean it owns the %current
359 : * context. When direct reclaim path tries to allocate memory, the
360 : * allocation context is nested inside whatever %current was doing at the
361 : * time of the original allocation. The nested allocation may be allowed
362 : * to block but modifying anything %current owns can corrupt the outer
363 : * context's expectations.
364 : *
365 : * %true result from this function indicates that the allocation context
366 : * can sleep and use anything that's associated with %current.
367 : */
368 411 : static inline bool gfpflags_normal_context(const gfp_t gfp_flags)
369 : {
370 411 : return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) ==
371 : __GFP_DIRECT_RECLAIM;
372 : }
373 :
374 : #ifdef CONFIG_HIGHMEM
375 : #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
376 : #else
377 : #define OPT_ZONE_HIGHMEM ZONE_NORMAL
378 : #endif
379 :
380 : #ifdef CONFIG_ZONE_DMA
381 : #define OPT_ZONE_DMA ZONE_DMA
382 : #else
383 : #define OPT_ZONE_DMA ZONE_NORMAL
384 : #endif
385 :
386 : #ifdef CONFIG_ZONE_DMA32
387 : #define OPT_ZONE_DMA32 ZONE_DMA32
388 : #else
389 : #define OPT_ZONE_DMA32 ZONE_NORMAL
390 : #endif
391 :
392 : /*
393 : * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
394 : * zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT
395 : * bits long and there are 16 of them to cover all possible combinations of
396 : * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
397 : *
398 : * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
399 : * But GFP_MOVABLE is not only a zone specifier but also an allocation
400 : * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
401 : * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
402 : *
403 : * bit result
404 : * =================
405 : * 0x0 => NORMAL
406 : * 0x1 => DMA or NORMAL
407 : * 0x2 => HIGHMEM or NORMAL
408 : * 0x3 => BAD (DMA+HIGHMEM)
409 : * 0x4 => DMA32 or NORMAL
410 : * 0x5 => BAD (DMA+DMA32)
411 : * 0x6 => BAD (HIGHMEM+DMA32)
412 : * 0x7 => BAD (HIGHMEM+DMA32+DMA)
413 : * 0x8 => NORMAL (MOVABLE+0)
414 : * 0x9 => DMA or NORMAL (MOVABLE+DMA)
415 : * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
416 : * 0xb => BAD (MOVABLE+HIGHMEM+DMA)
417 : * 0xc => DMA32 or NORMAL (MOVABLE+DMA32)
418 : * 0xd => BAD (MOVABLE+DMA32+DMA)
419 : * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
420 : * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
421 : *
422 : * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
423 : */
424 :
425 : #if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
426 : /* ZONE_DEVICE is not a valid GFP zone specifier */
427 : #define GFP_ZONES_SHIFT 2
428 : #else
429 : #define GFP_ZONES_SHIFT ZONES_SHIFT
430 : #endif
431 :
432 : #if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
433 : #error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
434 : #endif
435 :
436 : #define GFP_ZONE_TABLE ( \
437 : (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \
438 : | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \
439 : | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \
440 : | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \
441 : | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \
442 : | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \
443 : | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
444 : | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\
445 : )
446 :
447 : /*
448 : * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
449 : * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
450 : * entry starting with bit 0. Bit is set if the combination is not
451 : * allowed.
452 : */
453 : #define GFP_ZONE_BAD ( \
454 : 1 << (___GFP_DMA | ___GFP_HIGHMEM) \
455 : | 1 << (___GFP_DMA | ___GFP_DMA32) \
456 : | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
457 : | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
458 : | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
459 : | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
460 : | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
461 : | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
462 : )
463 :
464 221275 : static inline enum zone_type gfp_zone(gfp_t flags)
465 : {
466 221275 : enum zone_type z;
467 221275 : int bit = (__force int) (flags & GFP_ZONEMASK);
468 :
469 221275 : z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) &
470 : ((1 << GFP_ZONES_SHIFT) - 1);
471 221268 : VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
472 28139 : return z;
473 : }
474 :
475 : /*
476 : * There is only one page-allocator function, and two main namespaces to
477 : * it. The alloc_page*() variants return 'struct page *' and as such
478 : * can allocate highmem pages, the *get*page*() variants return
479 : * virtual kernel addresses to the allocated page(s).
480 : */
481 :
482 220478 : static inline int gfp_zonelist(gfp_t flags)
483 : {
484 : #ifdef CONFIG_NUMA
485 220478 : if (unlikely(flags & __GFP_THISNODE))
486 19 : return ZONELIST_NOFALLBACK;
487 : #endif
488 : return ZONELIST_FALLBACK;
489 : }
490 :
491 : /*
492 : * We get the zone list from the current node and the gfp_mask.
493 : * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
494 : * There are two zonelists per node, one for all zones with memory and
495 : * one containing just zones from the node the zonelist belongs to.
496 : *
497 : * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
498 : * optimized to &contig_page_data at compile-time.
499 : */
500 220478 : static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
501 : {
502 220497 : return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
503 : }
504 :
505 : #ifndef HAVE_ARCH_FREE_PAGE
506 : static inline void arch_free_page(struct page *page, int order) { }
507 : #endif
508 : #ifndef HAVE_ARCH_ALLOC_PAGE
509 193031 : static inline void arch_alloc_page(struct page *page, int order) { }
510 : #endif
511 : #ifndef HAVE_ARCH_MAKE_PAGE_ACCESSIBLE
512 1284 : static inline int arch_make_page_accessible(struct page *page)
513 : {
514 1284 : return 0;
515 : }
516 : #endif
517 :
518 : struct page *
519 : __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid,
520 : nodemask_t *nodemask);
521 :
522 : static inline struct page *
523 4884 : __alloc_pages(gfp_t gfp_mask, unsigned int order, int preferred_nid)
524 : {
525 4867 : return __alloc_pages_nodemask(gfp_mask, order, preferred_nid, NULL);
526 : }
527 :
528 : /*
529 : * Allocate pages, preferring the node given as nid. The node must be valid and
530 : * online. For more general interface, see alloc_pages_node().
531 : */
532 : static inline struct page *
533 1164 : __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
534 : {
535 1164 : VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
536 1202 : VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid));
537 :
538 1164 : return __alloc_pages(gfp_mask, order, nid);
539 : }
540 :
541 : /*
542 : * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
543 : * prefer the current CPU's closest node. Otherwise node must be valid and
544 : * online.
545 : */
546 1109 : static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
547 : unsigned int order)
548 : {
549 1109 : if (nid == NUMA_NO_NODE)
550 884 : nid = numa_mem_id();
551 :
552 1109 : return __alloc_pages_node(nid, gfp_mask, order);
553 : }
554 :
555 : #ifdef CONFIG_NUMA
556 : extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
557 :
558 : static inline struct page *
559 117220 : alloc_pages(gfp_t gfp_mask, unsigned int order)
560 : {
561 117220 : return alloc_pages_current(gfp_mask, order);
562 : }
563 : extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
564 : struct vm_area_struct *vma, unsigned long addr,
565 : int node, bool hugepage);
566 : #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
567 : alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
568 : #else
569 : static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order)
570 : {
571 : return alloc_pages_node(numa_node_id(), gfp_mask, order);
572 : }
573 : #define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
574 : alloc_pages(gfp_mask, order)
575 : #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
576 : alloc_pages(gfp_mask, order)
577 : #endif
578 : #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
579 : #define alloc_page_vma(gfp_mask, vma, addr) \
580 : alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false)
581 :
582 : extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
583 : extern unsigned long get_zeroed_page(gfp_t gfp_mask);
584 :
585 : void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
586 : void free_pages_exact(void *virt, size_t size);
587 : void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
588 :
589 : #define __get_free_page(gfp_mask) \
590 : __get_free_pages((gfp_mask), 0)
591 :
592 : #define __get_dma_pages(gfp_mask, order) \
593 : __get_free_pages((gfp_mask) | GFP_DMA, (order))
594 :
595 : extern void __free_pages(struct page *page, unsigned int order);
596 : extern void free_pages(unsigned long addr, unsigned int order);
597 :
598 : struct page_frag_cache;
599 : extern void __page_frag_cache_drain(struct page *page, unsigned int count);
600 : extern void *page_frag_alloc_align(struct page_frag_cache *nc,
601 : unsigned int fragsz, gfp_t gfp_mask,
602 : unsigned int align_mask);
603 :
604 0 : static inline void *page_frag_alloc(struct page_frag_cache *nc,
605 : unsigned int fragsz, gfp_t gfp_mask)
606 : {
607 0 : return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u);
608 : }
609 :
610 : extern void page_frag_free(void *addr);
611 :
612 : #define __free_page(page) __free_pages((page), 0)
613 : #define free_page(addr) free_pages((addr), 0)
614 :
615 : void page_alloc_init(void);
616 : void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
617 : void drain_all_pages(struct zone *zone);
618 : void drain_local_pages(struct zone *zone);
619 :
620 : void page_alloc_init_late(void);
621 :
622 : /*
623 : * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
624 : * GFP flags are used before interrupts are enabled. Once interrupts are
625 : * enabled, it is set to __GFP_BITS_MASK while the system is running. During
626 : * hibernation, it is used by PM to avoid I/O during memory allocation while
627 : * devices are suspended.
628 : */
629 : extern gfp_t gfp_allowed_mask;
630 :
631 : /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
632 : bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
633 :
634 : extern void pm_restrict_gfp_mask(void);
635 : extern void pm_restore_gfp_mask(void);
636 :
637 : extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma);
638 :
639 : #ifdef CONFIG_PM_SLEEP
640 : extern bool pm_suspended_storage(void);
641 : #else
642 0 : static inline bool pm_suspended_storage(void)
643 : {
644 0 : return false;
645 : }
646 : #endif /* CONFIG_PM_SLEEP */
647 :
648 : #ifdef CONFIG_CONTIG_ALLOC
649 : /* The below functions must be run on a range from a single zone. */
650 : extern int alloc_contig_range(unsigned long start, unsigned long end,
651 : unsigned migratetype, gfp_t gfp_mask);
652 : extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
653 : int nid, nodemask_t *nodemask);
654 : #endif
655 : void free_contig_range(unsigned long pfn, unsigned int nr_pages);
656 :
657 : #ifdef CONFIG_CMA
658 : /* CMA stuff */
659 : extern void init_cma_reserved_pageblock(struct page *page);
660 : #endif
661 :
662 : #endif /* __LINUX_GFP_H */
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