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 : #define ___GFP_ZEROTAGS 0x800000u
57 : #ifdef CONFIG_KASAN_HW_TAGS
58 : #define ___GFP_SKIP_ZERO 0x1000000u
59 : #define ___GFP_SKIP_KASAN_UNPOISON 0x2000000u
60 : #define ___GFP_SKIP_KASAN_POISON 0x4000000u
61 : #else
62 : #define ___GFP_SKIP_ZERO 0
63 : #define ___GFP_SKIP_KASAN_UNPOISON 0
64 : #define ___GFP_SKIP_KASAN_POISON 0
65 : #endif
66 : #ifdef CONFIG_LOCKDEP
67 : #define ___GFP_NOLOCKDEP 0x8000000u
68 : #else
69 : #define ___GFP_NOLOCKDEP 0
70 : #endif
71 : /* If the above are modified, __GFP_BITS_SHIFT may need updating */
72 :
73 : /*
74 : * Physical address zone modifiers (see linux/mmzone.h - low four bits)
75 : *
76 : * Do not put any conditional on these. If necessary modify the definitions
77 : * without the underscores and use them consistently. The definitions here may
78 : * be used in bit comparisons.
79 : */
80 : #define __GFP_DMA ((__force gfp_t)___GFP_DMA)
81 : #define __GFP_HIGHMEM ((__force gfp_t)___GFP_HIGHMEM)
82 : #define __GFP_DMA32 ((__force gfp_t)___GFP_DMA32)
83 : #define __GFP_MOVABLE ((__force gfp_t)___GFP_MOVABLE) /* ZONE_MOVABLE allowed */
84 : #define GFP_ZONEMASK (__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
85 :
86 : /**
87 : * DOC: Page mobility and placement hints
88 : *
89 : * Page mobility and placement hints
90 : * ---------------------------------
91 : *
92 : * These flags provide hints about how mobile the page is. Pages with similar
93 : * mobility are placed within the same pageblocks to minimise problems due
94 : * to external fragmentation.
95 : *
96 : * %__GFP_MOVABLE (also a zone modifier) indicates that the page can be
97 : * moved by page migration during memory compaction or can be reclaimed.
98 : *
99 : * %__GFP_RECLAIMABLE is used for slab allocations that specify
100 : * SLAB_RECLAIM_ACCOUNT and whose pages can be freed via shrinkers.
101 : *
102 : * %__GFP_WRITE indicates the caller intends to dirty the page. Where possible,
103 : * these pages will be spread between local zones to avoid all the dirty
104 : * pages being in one zone (fair zone allocation policy).
105 : *
106 : * %__GFP_HARDWALL enforces the cpuset memory allocation policy.
107 : *
108 : * %__GFP_THISNODE forces the allocation to be satisfied from the requested
109 : * node with no fallbacks or placement policy enforcements.
110 : *
111 : * %__GFP_ACCOUNT causes the allocation to be accounted to kmemcg.
112 : */
113 : #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE)
114 : #define __GFP_WRITE ((__force gfp_t)___GFP_WRITE)
115 : #define __GFP_HARDWALL ((__force gfp_t)___GFP_HARDWALL)
116 : #define __GFP_THISNODE ((__force gfp_t)___GFP_THISNODE)
117 : #define __GFP_ACCOUNT ((__force gfp_t)___GFP_ACCOUNT)
118 :
119 : /**
120 : * DOC: Watermark modifiers
121 : *
122 : * Watermark modifiers -- controls access to emergency reserves
123 : * ------------------------------------------------------------
124 : *
125 : * %__GFP_HIGH indicates that the caller is high-priority and that granting
126 : * the request is necessary before the system can make forward progress.
127 : * For example, creating an IO context to clean pages.
128 : *
129 : * %__GFP_ATOMIC indicates that the caller cannot reclaim or sleep and is
130 : * high priority. Users are typically interrupt handlers. This may be
131 : * used in conjunction with %__GFP_HIGH
132 : *
133 : * %__GFP_MEMALLOC allows access to all memory. This should only be used when
134 : * the caller guarantees the allocation will allow more memory to be freed
135 : * very shortly e.g. process exiting or swapping. Users either should
136 : * be the MM or co-ordinating closely with the VM (e.g. swap over NFS).
137 : * Users of this flag have to be extremely careful to not deplete the reserve
138 : * completely and implement a throttling mechanism which controls the
139 : * consumption of the reserve based on the amount of freed memory.
140 : * Usage of a pre-allocated pool (e.g. mempool) should be always considered
141 : * before using this flag.
142 : *
143 : * %__GFP_NOMEMALLOC is used to explicitly forbid access to emergency reserves.
144 : * This takes precedence over the %__GFP_MEMALLOC flag if both are set.
145 : */
146 : #define __GFP_ATOMIC ((__force gfp_t)___GFP_ATOMIC)
147 : #define __GFP_HIGH ((__force gfp_t)___GFP_HIGH)
148 : #define __GFP_MEMALLOC ((__force gfp_t)___GFP_MEMALLOC)
149 : #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC)
150 :
151 : /**
152 : * DOC: Reclaim modifiers
153 : *
154 : * Reclaim modifiers
155 : * -----------------
156 : * Please note that all the following flags are only applicable to sleepable
157 : * allocations (e.g. %GFP_NOWAIT and %GFP_ATOMIC will ignore them).
158 : *
159 : * %__GFP_IO can start physical IO.
160 : *
161 : * %__GFP_FS can call down to the low-level FS. Clearing the flag avoids the
162 : * allocator recursing into the filesystem which might already be holding
163 : * locks.
164 : *
165 : * %__GFP_DIRECT_RECLAIM indicates that the caller may enter direct reclaim.
166 : * This flag can be cleared to avoid unnecessary delays when a fallback
167 : * option is available.
168 : *
169 : * %__GFP_KSWAPD_RECLAIM indicates that the caller wants to wake kswapd when
170 : * the low watermark is reached and have it reclaim pages until the high
171 : * watermark is reached. A caller may wish to clear this flag when fallback
172 : * options are available and the reclaim is likely to disrupt the system. The
173 : * canonical example is THP allocation where a fallback is cheap but
174 : * reclaim/compaction may cause indirect stalls.
175 : *
176 : * %__GFP_RECLAIM is shorthand to allow/forbid both direct and kswapd reclaim.
177 : *
178 : * The default allocator behavior depends on the request size. We have a concept
179 : * of so called costly allocations (with order > %PAGE_ALLOC_COSTLY_ORDER).
180 : * !costly allocations are too essential to fail so they are implicitly
181 : * non-failing by default (with some exceptions like OOM victims might fail so
182 : * the caller still has to check for failures) while costly requests try to be
183 : * not disruptive and back off even without invoking the OOM killer.
184 : * The following three modifiers might be used to override some of these
185 : * implicit rules
186 : *
187 : * %__GFP_NORETRY: The VM implementation will try only very lightweight
188 : * memory direct reclaim to get some memory under memory pressure (thus
189 : * it can sleep). It will avoid disruptive actions like OOM killer. The
190 : * caller must handle the failure which is quite likely to happen under
191 : * heavy memory pressure. The flag is suitable when failure can easily be
192 : * handled at small cost, such as reduced throughput
193 : *
194 : * %__GFP_RETRY_MAYFAIL: The VM implementation will retry memory reclaim
195 : * procedures that have previously failed if there is some indication
196 : * that progress has been made else where. It can wait for other
197 : * tasks to attempt high level approaches to freeing memory such as
198 : * compaction (which removes fragmentation) and page-out.
199 : * There is still a definite limit to the number of retries, but it is
200 : * a larger limit than with %__GFP_NORETRY.
201 : * Allocations with this flag may fail, but only when there is
202 : * genuinely little unused memory. While these allocations do not
203 : * directly trigger the OOM killer, their failure indicates that
204 : * the system is likely to need to use the OOM killer soon. The
205 : * caller must handle failure, but can reasonably do so by failing
206 : * a higher-level request, or completing it only in a much less
207 : * efficient manner.
208 : * If the allocation does fail, and the caller is in a position to
209 : * free some non-essential memory, doing so could benefit the system
210 : * as a whole.
211 : *
212 : * %__GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
213 : * cannot handle allocation failures. The allocation could block
214 : * indefinitely but will never return with failure. Testing for
215 : * failure is pointless.
216 : * New users should be evaluated carefully (and the flag should be
217 : * used only when there is no reasonable failure policy) but it is
218 : * definitely preferable to use the flag rather than opencode endless
219 : * loop around allocator.
220 : * Using this flag for costly allocations is _highly_ discouraged.
221 : */
222 : #define __GFP_IO ((__force gfp_t)___GFP_IO)
223 : #define __GFP_FS ((__force gfp_t)___GFP_FS)
224 : #define __GFP_DIRECT_RECLAIM ((__force gfp_t)___GFP_DIRECT_RECLAIM) /* Caller can reclaim */
225 : #define __GFP_KSWAPD_RECLAIM ((__force gfp_t)___GFP_KSWAPD_RECLAIM) /* kswapd can wake */
226 : #define __GFP_RECLAIM ((__force gfp_t)(___GFP_DIRECT_RECLAIM|___GFP_KSWAPD_RECLAIM))
227 : #define __GFP_RETRY_MAYFAIL ((__force gfp_t)___GFP_RETRY_MAYFAIL)
228 : #define __GFP_NOFAIL ((__force gfp_t)___GFP_NOFAIL)
229 : #define __GFP_NORETRY ((__force gfp_t)___GFP_NORETRY)
230 :
231 : /**
232 : * DOC: Action modifiers
233 : *
234 : * Action modifiers
235 : * ----------------
236 : *
237 : * %__GFP_NOWARN suppresses allocation failure reports.
238 : *
239 : * %__GFP_COMP address compound page metadata.
240 : *
241 : * %__GFP_ZERO returns a zeroed page on success.
242 : *
243 : * %__GFP_ZEROTAGS zeroes memory tags at allocation time if the memory itself
244 : * is being zeroed (either via __GFP_ZERO or via init_on_alloc, provided that
245 : * __GFP_SKIP_ZERO is not set). This flag is intended for optimization: setting
246 : * memory tags at the same time as zeroing memory has minimal additional
247 : * performace impact.
248 : *
249 : * %__GFP_SKIP_KASAN_UNPOISON makes KASAN skip unpoisoning on page allocation.
250 : * Only effective in HW_TAGS mode.
251 : *
252 : * %__GFP_SKIP_KASAN_POISON makes KASAN skip poisoning on page deallocation.
253 : * Typically, used for userspace pages. Only effective in HW_TAGS mode.
254 : */
255 : #define __GFP_NOWARN ((__force gfp_t)___GFP_NOWARN)
256 : #define __GFP_COMP ((__force gfp_t)___GFP_COMP)
257 : #define __GFP_ZERO ((__force gfp_t)___GFP_ZERO)
258 : #define __GFP_ZEROTAGS ((__force gfp_t)___GFP_ZEROTAGS)
259 : #define __GFP_SKIP_ZERO ((__force gfp_t)___GFP_SKIP_ZERO)
260 : #define __GFP_SKIP_KASAN_UNPOISON ((__force gfp_t)___GFP_SKIP_KASAN_UNPOISON)
261 : #define __GFP_SKIP_KASAN_POISON ((__force gfp_t)___GFP_SKIP_KASAN_POISON)
262 :
263 : /* Disable lockdep for GFP context tracking */
264 : #define __GFP_NOLOCKDEP ((__force gfp_t)___GFP_NOLOCKDEP)
265 :
266 : /* Room for N __GFP_FOO bits */
267 : #define __GFP_BITS_SHIFT (27 + IS_ENABLED(CONFIG_LOCKDEP))
268 : #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
269 :
270 : /**
271 : * DOC: Useful GFP flag combinations
272 : *
273 : * Useful GFP flag combinations
274 : * ----------------------------
275 : *
276 : * Useful GFP flag combinations that are commonly used. It is recommended
277 : * that subsystems start with one of these combinations and then set/clear
278 : * %__GFP_FOO flags as necessary.
279 : *
280 : * %GFP_ATOMIC users can not sleep and need the allocation to succeed. A lower
281 : * watermark is applied to allow access to "atomic reserves".
282 : * The current implementation doesn't support NMI and few other strict
283 : * non-preemptive contexts (e.g. raw_spin_lock). The same applies to %GFP_NOWAIT.
284 : *
285 : * %GFP_KERNEL is typical for kernel-internal allocations. The caller requires
286 : * %ZONE_NORMAL or a lower zone for direct access but can direct reclaim.
287 : *
288 : * %GFP_KERNEL_ACCOUNT is the same as GFP_KERNEL, except the allocation is
289 : * accounted to kmemcg.
290 : *
291 : * %GFP_NOWAIT is for kernel allocations that should not stall for direct
292 : * reclaim, start physical IO or use any filesystem callback.
293 : *
294 : * %GFP_NOIO will use direct reclaim to discard clean pages or slab pages
295 : * that do not require the starting of any physical IO.
296 : * Please try to avoid using this flag directly and instead use
297 : * memalloc_noio_{save,restore} to mark the whole scope which cannot
298 : * perform any IO with a short explanation why. All allocation requests
299 : * will inherit GFP_NOIO implicitly.
300 : *
301 : * %GFP_NOFS will use direct reclaim but will not use any filesystem interfaces.
302 : * Please try to avoid using this flag directly and instead use
303 : * memalloc_nofs_{save,restore} to mark the whole scope which cannot/shouldn't
304 : * recurse into the FS layer with a short explanation why. All allocation
305 : * requests will inherit GFP_NOFS implicitly.
306 : *
307 : * %GFP_USER is for userspace allocations that also need to be directly
308 : * accessibly by the kernel or hardware. It is typically used by hardware
309 : * for buffers that are mapped to userspace (e.g. graphics) that hardware
310 : * still must DMA to. cpuset limits are enforced for these allocations.
311 : *
312 : * %GFP_DMA exists for historical reasons and should be avoided where possible.
313 : * The flags indicates that the caller requires that the lowest zone be
314 : * used (%ZONE_DMA or 16M on x86-64). Ideally, this would be removed but
315 : * it would require careful auditing as some users really require it and
316 : * others use the flag to avoid lowmem reserves in %ZONE_DMA and treat the
317 : * lowest zone as a type of emergency reserve.
318 : *
319 : * %GFP_DMA32 is similar to %GFP_DMA except that the caller requires a 32-bit
320 : * address. Note that kmalloc(..., GFP_DMA32) does not return DMA32 memory
321 : * because the DMA32 kmalloc cache array is not implemented.
322 : * (Reason: there is no such user in kernel).
323 : *
324 : * %GFP_HIGHUSER is for userspace allocations that may be mapped to userspace,
325 : * do not need to be directly accessible by the kernel but that cannot
326 : * move once in use. An example may be a hardware allocation that maps
327 : * data directly into userspace but has no addressing limitations.
328 : *
329 : * %GFP_HIGHUSER_MOVABLE is for userspace allocations that the kernel does not
330 : * need direct access to but can use kmap() when access is required. They
331 : * are expected to be movable via page reclaim or page migration. Typically,
332 : * pages on the LRU would also be allocated with %GFP_HIGHUSER_MOVABLE.
333 : *
334 : * %GFP_TRANSHUGE and %GFP_TRANSHUGE_LIGHT are used for THP allocations. They
335 : * are compound allocations that will generally fail quickly if memory is not
336 : * available and will not wake kswapd/kcompactd on failure. The _LIGHT
337 : * version does not attempt reclaim/compaction at all and is by default used
338 : * in page fault path, while the non-light is used by khugepaged.
339 : */
340 : #define GFP_ATOMIC (__GFP_HIGH|__GFP_ATOMIC|__GFP_KSWAPD_RECLAIM)
341 : #define GFP_KERNEL (__GFP_RECLAIM | __GFP_IO | __GFP_FS)
342 : #define GFP_KERNEL_ACCOUNT (GFP_KERNEL | __GFP_ACCOUNT)
343 : #define GFP_NOWAIT (__GFP_KSWAPD_RECLAIM)
344 : #define GFP_NOIO (__GFP_RECLAIM)
345 : #define GFP_NOFS (__GFP_RECLAIM | __GFP_IO)
346 : #define GFP_USER (__GFP_RECLAIM | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
347 : #define GFP_DMA __GFP_DMA
348 : #define GFP_DMA32 __GFP_DMA32
349 : #define GFP_HIGHUSER (GFP_USER | __GFP_HIGHMEM)
350 : #define GFP_HIGHUSER_MOVABLE (GFP_HIGHUSER | __GFP_MOVABLE | \
351 : __GFP_SKIP_KASAN_POISON)
352 : #define GFP_TRANSHUGE_LIGHT ((GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
353 : __GFP_NOMEMALLOC | __GFP_NOWARN) & ~__GFP_RECLAIM)
354 : #define GFP_TRANSHUGE (GFP_TRANSHUGE_LIGHT | __GFP_DIRECT_RECLAIM)
355 :
356 : /* Convert GFP flags to their corresponding migrate type */
357 : #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
358 : #define GFP_MOVABLE_SHIFT 3
359 :
360 : static inline int gfp_migratetype(const gfp_t gfp_flags)
361 : {
362 : VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
363 : BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
364 : BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
365 :
366 483 : if (unlikely(page_group_by_mobility_disabled))
367 : return MIGRATE_UNMOVABLE;
368 :
369 : /* Group based on mobility */
370 483 : return (gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
371 : }
372 : #undef GFP_MOVABLE_MASK
373 : #undef GFP_MOVABLE_SHIFT
374 :
375 : static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
376 : {
377 328 : return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
378 : }
379 :
380 : /**
381 : * gfpflags_normal_context - is gfp_flags a normal sleepable context?
382 : * @gfp_flags: gfp_flags to test
383 : *
384 : * Test whether @gfp_flags indicates that the allocation is from the
385 : * %current context and allowed to sleep.
386 : *
387 : * An allocation being allowed to block doesn't mean it owns the %current
388 : * context. When direct reclaim path tries to allocate memory, the
389 : * allocation context is nested inside whatever %current was doing at the
390 : * time of the original allocation. The nested allocation may be allowed
391 : * to block but modifying anything %current owns can corrupt the outer
392 : * context's expectations.
393 : *
394 : * %true result from this function indicates that the allocation context
395 : * can sleep and use anything that's associated with %current.
396 : */
397 : static inline bool gfpflags_normal_context(const gfp_t gfp_flags)
398 : {
399 : return (gfp_flags & (__GFP_DIRECT_RECLAIM | __GFP_MEMALLOC)) ==
400 : __GFP_DIRECT_RECLAIM;
401 : }
402 :
403 : #ifdef CONFIG_HIGHMEM
404 : #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
405 : #else
406 : #define OPT_ZONE_HIGHMEM ZONE_NORMAL
407 : #endif
408 :
409 : #ifdef CONFIG_ZONE_DMA
410 : #define OPT_ZONE_DMA ZONE_DMA
411 : #else
412 : #define OPT_ZONE_DMA ZONE_NORMAL
413 : #endif
414 :
415 : #ifdef CONFIG_ZONE_DMA32
416 : #define OPT_ZONE_DMA32 ZONE_DMA32
417 : #else
418 : #define OPT_ZONE_DMA32 ZONE_NORMAL
419 : #endif
420 :
421 : /*
422 : * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
423 : * zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT
424 : * bits long and there are 16 of them to cover all possible combinations of
425 : * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
426 : *
427 : * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
428 : * But GFP_MOVABLE is not only a zone specifier but also an allocation
429 : * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
430 : * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
431 : *
432 : * bit result
433 : * =================
434 : * 0x0 => NORMAL
435 : * 0x1 => DMA or NORMAL
436 : * 0x2 => HIGHMEM or NORMAL
437 : * 0x3 => BAD (DMA+HIGHMEM)
438 : * 0x4 => DMA32 or NORMAL
439 : * 0x5 => BAD (DMA+DMA32)
440 : * 0x6 => BAD (HIGHMEM+DMA32)
441 : * 0x7 => BAD (HIGHMEM+DMA32+DMA)
442 : * 0x8 => NORMAL (MOVABLE+0)
443 : * 0x9 => DMA or NORMAL (MOVABLE+DMA)
444 : * 0xa => MOVABLE (Movable is valid only if HIGHMEM is set too)
445 : * 0xb => BAD (MOVABLE+HIGHMEM+DMA)
446 : * 0xc => DMA32 or NORMAL (MOVABLE+DMA32)
447 : * 0xd => BAD (MOVABLE+DMA32+DMA)
448 : * 0xe => BAD (MOVABLE+DMA32+HIGHMEM)
449 : * 0xf => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
450 : *
451 : * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
452 : */
453 :
454 : #if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
455 : /* ZONE_DEVICE is not a valid GFP zone specifier */
456 : #define GFP_ZONES_SHIFT 2
457 : #else
458 : #define GFP_ZONES_SHIFT ZONES_SHIFT
459 : #endif
460 :
461 : #if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
462 : #error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
463 : #endif
464 :
465 : #define GFP_ZONE_TABLE ( \
466 : (ZONE_NORMAL << 0 * GFP_ZONES_SHIFT) \
467 : | (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT) \
468 : | (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT) \
469 : | (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT) \
470 : | (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT) \
471 : | (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT) \
472 : | (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
473 : | (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\
474 : )
475 :
476 : /*
477 : * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
478 : * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
479 : * entry starting with bit 0. Bit is set if the combination is not
480 : * allowed.
481 : */
482 : #define GFP_ZONE_BAD ( \
483 : 1 << (___GFP_DMA | ___GFP_HIGHMEM) \
484 : | 1 << (___GFP_DMA | ___GFP_DMA32) \
485 : | 1 << (___GFP_DMA32 | ___GFP_HIGHMEM) \
486 : | 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM) \
487 : | 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA) \
488 : | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA) \
489 : | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM) \
490 : | 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM) \
491 : )
492 :
493 : static inline enum zone_type gfp_zone(gfp_t flags)
494 : {
495 : enum zone_type z;
496 486 : int bit = (__force int) (flags & GFP_ZONEMASK);
497 :
498 486 : z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) &
499 : ((1 << GFP_ZONES_SHIFT) - 1);
500 : VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
501 : return z;
502 : }
503 :
504 : /*
505 : * There is only one page-allocator function, and two main namespaces to
506 : * it. The alloc_page*() variants return 'struct page *' and as such
507 : * can allocate highmem pages, the *get*page*() variants return
508 : * virtual kernel addresses to the allocated page(s).
509 : */
510 :
511 : static inline int gfp_zonelist(gfp_t flags)
512 : {
513 : #ifdef CONFIG_NUMA
514 : if (unlikely(flags & __GFP_THISNODE))
515 : return ZONELIST_NOFALLBACK;
516 : #endif
517 : return ZONELIST_FALLBACK;
518 : }
519 :
520 : /*
521 : * We get the zone list from the current node and the gfp_mask.
522 : * This zone list contains a maximum of MAX_NUMNODES*MAX_NR_ZONES zones.
523 : * There are two zonelists per node, one for all zones with memory and
524 : * one containing just zones from the node the zonelist belongs to.
525 : *
526 : * For the case of non-NUMA systems the NODE_DATA() gets optimized to
527 : * &contig_page_data at compile-time.
528 : */
529 : static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
530 : {
531 486 : return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
532 : }
533 :
534 : #ifndef HAVE_ARCH_FREE_PAGE
535 : static inline void arch_free_page(struct page *page, int order) { }
536 : #endif
537 : #ifndef HAVE_ARCH_ALLOC_PAGE
538 : static inline void arch_alloc_page(struct page *page, int order) { }
539 : #endif
540 :
541 : struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid,
542 : nodemask_t *nodemask);
543 : struct folio *__folio_alloc(gfp_t gfp, unsigned int order, int preferred_nid,
544 : nodemask_t *nodemask);
545 :
546 : unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid,
547 : nodemask_t *nodemask, int nr_pages,
548 : struct list_head *page_list,
549 : struct page **page_array);
550 :
551 : unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp,
552 : unsigned long nr_pages,
553 : struct page **page_array);
554 :
555 : /* Bulk allocate order-0 pages */
556 : static inline unsigned long
557 : alloc_pages_bulk_list(gfp_t gfp, unsigned long nr_pages, struct list_head *list)
558 : {
559 : return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, list, NULL);
560 : }
561 :
562 : static inline unsigned long
563 : alloc_pages_bulk_array(gfp_t gfp, unsigned long nr_pages, struct page **page_array)
564 : {
565 : return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, NULL, page_array);
566 : }
567 :
568 : static inline unsigned long
569 : alloc_pages_bulk_array_node(gfp_t gfp, int nid, unsigned long nr_pages, struct page **page_array)
570 : {
571 15 : if (nid == NUMA_NO_NODE)
572 15 : nid = numa_mem_id();
573 :
574 15 : return __alloc_pages_bulk(gfp, nid, NULL, nr_pages, NULL, page_array);
575 : }
576 :
577 : /*
578 : * Allocate pages, preferring the node given as nid. The node must be valid and
579 : * online. For more general interface, see alloc_pages_node().
580 : */
581 : static inline struct page *
582 : __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
583 : {
584 : VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
585 : VM_WARN_ON((gfp_mask & __GFP_THISNODE) && !node_online(nid));
586 :
587 468 : return __alloc_pages(gfp_mask, order, nid, NULL);
588 : }
589 :
590 : static inline
591 : struct folio *__folio_alloc_node(gfp_t gfp, unsigned int order, int nid)
592 : {
593 : VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
594 : VM_WARN_ON((gfp & __GFP_THISNODE) && !node_online(nid));
595 :
596 0 : return __folio_alloc(gfp, order, nid, NULL);
597 : }
598 :
599 : /*
600 : * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
601 : * prefer the current CPU's closest node. Otherwise node must be valid and
602 : * online.
603 : */
604 : static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
605 : unsigned int order)
606 : {
607 0 : if (nid == NUMA_NO_NODE)
608 0 : nid = numa_mem_id();
609 :
610 467 : return __alloc_pages_node(nid, gfp_mask, order);
611 : }
612 :
613 : #ifdef CONFIG_NUMA
614 : struct page *alloc_pages(gfp_t gfp, unsigned int order);
615 : struct folio *folio_alloc(gfp_t gfp, unsigned order);
616 : struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
617 : struct vm_area_struct *vma, unsigned long addr,
618 : bool hugepage);
619 : struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
620 : unsigned long addr, bool hugepage);
621 : #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
622 : alloc_pages_vma(gfp_mask, order, vma, addr, true)
623 : #else
624 : static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order)
625 : {
626 934 : return alloc_pages_node(numa_node_id(), gfp_mask, order);
627 : }
628 : static inline struct folio *folio_alloc(gfp_t gfp, unsigned int order)
629 : {
630 0 : return __folio_alloc_node(gfp, order, numa_node_id());
631 : }
632 : #define alloc_pages_vma(gfp_mask, order, vma, addr, hugepage) \
633 : alloc_pages(gfp_mask, order)
634 : #define vma_alloc_folio(gfp, order, vma, addr, hugepage) \
635 : folio_alloc(gfp, order)
636 : #define alloc_hugepage_vma(gfp_mask, vma, addr, order) \
637 : alloc_pages(gfp_mask, order)
638 : #endif
639 : #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
640 : #define alloc_page_vma(gfp_mask, vma, addr) \
641 : alloc_pages_vma(gfp_mask, 0, vma, addr, false)
642 :
643 : extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
644 : extern unsigned long get_zeroed_page(gfp_t gfp_mask);
645 :
646 : void *alloc_pages_exact(size_t size, gfp_t gfp_mask) __alloc_size(1);
647 : void free_pages_exact(void *virt, size_t size);
648 : __meminit void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask) __alloc_size(2);
649 :
650 : #define __get_free_page(gfp_mask) \
651 : __get_free_pages((gfp_mask), 0)
652 :
653 : #define __get_dma_pages(gfp_mask, order) \
654 : __get_free_pages((gfp_mask) | GFP_DMA, (order))
655 :
656 : extern void __free_pages(struct page *page, unsigned int order);
657 : extern void free_pages(unsigned long addr, unsigned int order);
658 :
659 : struct page_frag_cache;
660 : extern void __page_frag_cache_drain(struct page *page, unsigned int count);
661 : extern void *page_frag_alloc_align(struct page_frag_cache *nc,
662 : unsigned int fragsz, gfp_t gfp_mask,
663 : unsigned int align_mask);
664 :
665 : static inline void *page_frag_alloc(struct page_frag_cache *nc,
666 : unsigned int fragsz, gfp_t gfp_mask)
667 : {
668 : return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u);
669 : }
670 :
671 : extern void page_frag_free(void *addr);
672 :
673 : #define __free_page(page) __free_pages((page), 0)
674 : #define free_page(addr) free_pages((addr), 0)
675 :
676 : void page_alloc_init(void);
677 : void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
678 : void drain_all_pages(struct zone *zone);
679 : void drain_local_pages(struct zone *zone);
680 :
681 : void page_alloc_init_late(void);
682 :
683 : /*
684 : * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
685 : * GFP flags are used before interrupts are enabled. Once interrupts are
686 : * enabled, it is set to __GFP_BITS_MASK while the system is running. During
687 : * hibernation, it is used by PM to avoid I/O during memory allocation while
688 : * devices are suspended.
689 : */
690 : extern gfp_t gfp_allowed_mask;
691 :
692 : /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
693 : bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
694 :
695 : extern void pm_restrict_gfp_mask(void);
696 : extern void pm_restore_gfp_mask(void);
697 :
698 : extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma);
699 :
700 : #ifdef CONFIG_PM_SLEEP
701 : extern bool pm_suspended_storage(void);
702 : #else
703 : static inline bool pm_suspended_storage(void)
704 : {
705 : return false;
706 : }
707 : #endif /* CONFIG_PM_SLEEP */
708 :
709 : #ifdef CONFIG_CONTIG_ALLOC
710 : /* The below functions must be run on a range from a single zone. */
711 : extern int alloc_contig_range(unsigned long start, unsigned long end,
712 : unsigned migratetype, gfp_t gfp_mask);
713 : extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
714 : int nid, nodemask_t *nodemask);
715 : #endif
716 : void free_contig_range(unsigned long pfn, unsigned long nr_pages);
717 :
718 : #ifdef CONFIG_CMA
719 : /* CMA stuff */
720 : extern void init_cma_reserved_pageblock(struct page *page);
721 : #endif
722 :
723 : #endif /* __LINUX_GFP_H */
|
