xref: /linux/include/linux/gfp.h (revision a13d7201d7deedcbb6ac6efa94a1a7d34d3d79ec)
1 #ifndef __LINUX_GFP_H
2 #define __LINUX_GFP_H
3 
4 #include <linux/mmdebug.h>
5 #include <linux/mmzone.h>
6 #include <linux/stddef.h>
7 #include <linux/linkage.h>
8 #include <linux/topology.h>
9 
10 struct vm_area_struct;
11 
12 /* Plain integer GFP bitmasks. Do not use this directly. */
13 #define ___GFP_DMA		0x01u
14 #define ___GFP_HIGHMEM		0x02u
15 #define ___GFP_DMA32		0x04u
16 #define ___GFP_MOVABLE		0x08u
17 #define ___GFP_WAIT		0x10u
18 #define ___GFP_HIGH		0x20u
19 #define ___GFP_IO		0x40u
20 #define ___GFP_FS		0x80u
21 #define ___GFP_COLD		0x100u
22 #define ___GFP_NOWARN		0x200u
23 #define ___GFP_REPEAT		0x400u
24 #define ___GFP_NOFAIL		0x800u
25 #define ___GFP_NORETRY		0x1000u
26 #define ___GFP_MEMALLOC		0x2000u
27 #define ___GFP_COMP		0x4000u
28 #define ___GFP_ZERO		0x8000u
29 #define ___GFP_NOMEMALLOC	0x10000u
30 #define ___GFP_HARDWALL		0x20000u
31 #define ___GFP_THISNODE		0x40000u
32 #define ___GFP_RECLAIMABLE	0x80000u
33 #define ___GFP_NOACCOUNT	0x100000u
34 #define ___GFP_NOTRACK		0x200000u
35 #define ___GFP_NO_KSWAPD	0x400000u
36 #define ___GFP_OTHER_NODE	0x800000u
37 #define ___GFP_WRITE		0x1000000u
38 /* If the above are modified, __GFP_BITS_SHIFT may need updating */
39 
40 /*
41  * GFP bitmasks..
42  *
43  * Zone modifiers (see linux/mmzone.h - low three bits)
44  *
45  * Do not put any conditional on these. If necessary modify the definitions
46  * without the underscores and use them consistently. The definitions here may
47  * be used in bit comparisons.
48  */
49 #define __GFP_DMA	((__force gfp_t)___GFP_DMA)
50 #define __GFP_HIGHMEM	((__force gfp_t)___GFP_HIGHMEM)
51 #define __GFP_DMA32	((__force gfp_t)___GFP_DMA32)
52 #define __GFP_MOVABLE	((__force gfp_t)___GFP_MOVABLE)  /* Page is movable */
53 #define GFP_ZONEMASK	(__GFP_DMA|__GFP_HIGHMEM|__GFP_DMA32|__GFP_MOVABLE)
54 /*
55  * Action modifiers - doesn't change the zoning
56  *
57  * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
58  * _might_ fail.  This depends upon the particular VM implementation.
59  *
60  * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
61  * cannot handle allocation failures. New users should be evaluated carefully
62  * (and the flag should be used only when there is no reasonable failure policy)
63  * but it is definitely preferable to use the flag rather than opencode endless
64  * loop around allocator.
65  *
66  * __GFP_NORETRY: The VM implementation must not retry indefinitely.
67  *
68  * __GFP_MOVABLE: Flag that this page will be movable by the page migration
69  * mechanism or reclaimed
70  */
71 #define __GFP_WAIT	((__force gfp_t)___GFP_WAIT)	/* Can wait and reschedule? */
72 #define __GFP_HIGH	((__force gfp_t)___GFP_HIGH)	/* Should access emergency pools? */
73 #define __GFP_IO	((__force gfp_t)___GFP_IO)	/* Can start physical IO? */
74 #define __GFP_FS	((__force gfp_t)___GFP_FS)	/* Can call down to low-level FS? */
75 #define __GFP_COLD	((__force gfp_t)___GFP_COLD)	/* Cache-cold page required */
76 #define __GFP_NOWARN	((__force gfp_t)___GFP_NOWARN)	/* Suppress page allocation failure warning */
77 #define __GFP_REPEAT	((__force gfp_t)___GFP_REPEAT)	/* See above */
78 #define __GFP_NOFAIL	((__force gfp_t)___GFP_NOFAIL)	/* See above */
79 #define __GFP_NORETRY	((__force gfp_t)___GFP_NORETRY) /* See above */
80 #define __GFP_MEMALLOC	((__force gfp_t)___GFP_MEMALLOC)/* Allow access to emergency reserves */
81 #define __GFP_COMP	((__force gfp_t)___GFP_COMP)	/* Add compound page metadata */
82 #define __GFP_ZERO	((__force gfp_t)___GFP_ZERO)	/* Return zeroed page on success */
83 #define __GFP_NOMEMALLOC ((__force gfp_t)___GFP_NOMEMALLOC) /* Don't use emergency reserves.
84 							 * This takes precedence over the
85 							 * __GFP_MEMALLOC flag if both are
86 							 * set
87 							 */
88 #define __GFP_HARDWALL   ((__force gfp_t)___GFP_HARDWALL) /* Enforce hardwall cpuset memory allocs */
89 #define __GFP_THISNODE	((__force gfp_t)___GFP_THISNODE)/* No fallback, no policies */
90 #define __GFP_RECLAIMABLE ((__force gfp_t)___GFP_RECLAIMABLE) /* Page is reclaimable */
91 #define __GFP_NOACCOUNT	((__force gfp_t)___GFP_NOACCOUNT) /* Don't account to kmemcg */
92 #define __GFP_NOTRACK	((__force gfp_t)___GFP_NOTRACK)  /* Don't track with kmemcheck */
93 
94 #define __GFP_NO_KSWAPD	((__force gfp_t)___GFP_NO_KSWAPD)
95 #define __GFP_OTHER_NODE ((__force gfp_t)___GFP_OTHER_NODE) /* On behalf of other node */
96 #define __GFP_WRITE	((__force gfp_t)___GFP_WRITE)	/* Allocator intends to dirty page */
97 
98 /*
99  * This may seem redundant, but it's a way of annotating false positives vs.
100  * allocations that simply cannot be supported (e.g. page tables).
101  */
102 #define __GFP_NOTRACK_FALSE_POSITIVE (__GFP_NOTRACK)
103 
104 #define __GFP_BITS_SHIFT 25	/* Room for N __GFP_FOO bits */
105 #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
106 
107 /* This equals 0, but use constants in case they ever change */
108 #define GFP_NOWAIT	(GFP_ATOMIC & ~__GFP_HIGH)
109 /* GFP_ATOMIC means both !wait (__GFP_WAIT not set) and use emergency pool */
110 #define GFP_ATOMIC	(__GFP_HIGH)
111 #define GFP_NOIO	(__GFP_WAIT)
112 #define GFP_NOFS	(__GFP_WAIT | __GFP_IO)
113 #define GFP_KERNEL	(__GFP_WAIT | __GFP_IO | __GFP_FS)
114 #define GFP_TEMPORARY	(__GFP_WAIT | __GFP_IO | __GFP_FS | \
115 			 __GFP_RECLAIMABLE)
116 #define GFP_USER	(__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
117 #define GFP_HIGHUSER	(GFP_USER | __GFP_HIGHMEM)
118 #define GFP_HIGHUSER_MOVABLE	(GFP_HIGHUSER | __GFP_MOVABLE)
119 #define GFP_IOFS	(__GFP_IO | __GFP_FS)
120 #define GFP_TRANSHUGE	(GFP_HIGHUSER_MOVABLE | __GFP_COMP | \
121 			 __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | \
122 			 __GFP_NO_KSWAPD)
123 
124 /* This mask makes up all the page movable related flags */
125 #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
126 
127 /* Control page allocator reclaim behavior */
128 #define GFP_RECLAIM_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS|\
129 			__GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\
130 			__GFP_NORETRY|__GFP_MEMALLOC|__GFP_NOMEMALLOC)
131 
132 /* Control slab gfp mask during early boot */
133 #define GFP_BOOT_MASK (__GFP_BITS_MASK & ~(__GFP_WAIT|__GFP_IO|__GFP_FS))
134 
135 /* Control allocation constraints */
136 #define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
137 
138 /* Do not use these with a slab allocator */
139 #define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
140 
141 /* Flag - indicates that the buffer will be suitable for DMA.  Ignored on some
142    platforms, used as appropriate on others */
143 
144 #define GFP_DMA		__GFP_DMA
145 
146 /* 4GB DMA on some platforms */
147 #define GFP_DMA32	__GFP_DMA32
148 
149 /* Convert GFP flags to their corresponding migrate type */
150 static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
151 {
152 	WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
153 
154 	if (unlikely(page_group_by_mobility_disabled))
155 		return MIGRATE_UNMOVABLE;
156 
157 	/* Group based on mobility */
158 	return (((gfp_flags & __GFP_MOVABLE) != 0) << 1) |
159 		((gfp_flags & __GFP_RECLAIMABLE) != 0);
160 }
161 
162 #ifdef CONFIG_HIGHMEM
163 #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
164 #else
165 #define OPT_ZONE_HIGHMEM ZONE_NORMAL
166 #endif
167 
168 #ifdef CONFIG_ZONE_DMA
169 #define OPT_ZONE_DMA ZONE_DMA
170 #else
171 #define OPT_ZONE_DMA ZONE_NORMAL
172 #endif
173 
174 #ifdef CONFIG_ZONE_DMA32
175 #define OPT_ZONE_DMA32 ZONE_DMA32
176 #else
177 #define OPT_ZONE_DMA32 ZONE_NORMAL
178 #endif
179 
180 /*
181  * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
182  * zone to use given the lowest 4 bits of gfp_t. Entries are ZONE_SHIFT long
183  * and there are 16 of them to cover all possible combinations of
184  * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
185  *
186  * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
187  * But GFP_MOVABLE is not only a zone specifier but also an allocation
188  * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
189  * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
190  *
191  *       bit       result
192  *       =================
193  *       0x0    => NORMAL
194  *       0x1    => DMA or NORMAL
195  *       0x2    => HIGHMEM or NORMAL
196  *       0x3    => BAD (DMA+HIGHMEM)
197  *       0x4    => DMA32 or DMA or NORMAL
198  *       0x5    => BAD (DMA+DMA32)
199  *       0x6    => BAD (HIGHMEM+DMA32)
200  *       0x7    => BAD (HIGHMEM+DMA32+DMA)
201  *       0x8    => NORMAL (MOVABLE+0)
202  *       0x9    => DMA or NORMAL (MOVABLE+DMA)
203  *       0xa    => MOVABLE (Movable is valid only if HIGHMEM is set too)
204  *       0xb    => BAD (MOVABLE+HIGHMEM+DMA)
205  *       0xc    => DMA32 (MOVABLE+DMA32)
206  *       0xd    => BAD (MOVABLE+DMA32+DMA)
207  *       0xe    => BAD (MOVABLE+DMA32+HIGHMEM)
208  *       0xf    => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
209  *
210  * ZONES_SHIFT must be <= 2 on 32 bit platforms.
211  */
212 
213 #if 16 * ZONES_SHIFT > BITS_PER_LONG
214 #error ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
215 #endif
216 
217 #define GFP_ZONE_TABLE ( \
218 	(ZONE_NORMAL << 0 * ZONES_SHIFT)				      \
219 	| (OPT_ZONE_DMA << ___GFP_DMA * ZONES_SHIFT)			      \
220 	| (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * ZONES_SHIFT)		      \
221 	| (OPT_ZONE_DMA32 << ___GFP_DMA32 * ZONES_SHIFT)		      \
222 	| (ZONE_NORMAL << ___GFP_MOVABLE * ZONES_SHIFT)			      \
223 	| (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * ZONES_SHIFT)	      \
224 	| (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * ZONES_SHIFT)   \
225 	| (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * ZONES_SHIFT)   \
226 )
227 
228 /*
229  * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
230  * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
231  * entry starting with bit 0. Bit is set if the combination is not
232  * allowed.
233  */
234 #define GFP_ZONE_BAD ( \
235 	1 << (___GFP_DMA | ___GFP_HIGHMEM)				      \
236 	| 1 << (___GFP_DMA | ___GFP_DMA32)				      \
237 	| 1 << (___GFP_DMA32 | ___GFP_HIGHMEM)				      \
238 	| 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM)		      \
239 	| 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA)		      \
240 	| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA)		      \
241 	| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM)		      \
242 	| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM)  \
243 )
244 
245 static inline enum zone_type gfp_zone(gfp_t flags)
246 {
247 	enum zone_type z;
248 	int bit = (__force int) (flags & GFP_ZONEMASK);
249 
250 	z = (GFP_ZONE_TABLE >> (bit * ZONES_SHIFT)) &
251 					 ((1 << ZONES_SHIFT) - 1);
252 	VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
253 	return z;
254 }
255 
256 /*
257  * There is only one page-allocator function, and two main namespaces to
258  * it. The alloc_page*() variants return 'struct page *' and as such
259  * can allocate highmem pages, the *get*page*() variants return
260  * virtual kernel addresses to the allocated page(s).
261  */
262 
263 static inline int gfp_zonelist(gfp_t flags)
264 {
265 	if (IS_ENABLED(CONFIG_NUMA) && unlikely(flags & __GFP_THISNODE))
266 		return 1;
267 
268 	return 0;
269 }
270 
271 /*
272  * We get the zone list from the current node and the gfp_mask.
273  * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
274  * There are two zonelists per node, one for all zones with memory and
275  * one containing just zones from the node the zonelist belongs to.
276  *
277  * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
278  * optimized to &contig_page_data at compile-time.
279  */
280 static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
281 {
282 	return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
283 }
284 
285 #ifndef HAVE_ARCH_FREE_PAGE
286 static inline void arch_free_page(struct page *page, int order) { }
287 #endif
288 #ifndef HAVE_ARCH_ALLOC_PAGE
289 static inline void arch_alloc_page(struct page *page, int order) { }
290 #endif
291 
292 struct page *
293 __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
294 		       struct zonelist *zonelist, nodemask_t *nodemask);
295 
296 static inline struct page *
297 __alloc_pages(gfp_t gfp_mask, unsigned int order,
298 		struct zonelist *zonelist)
299 {
300 	return __alloc_pages_nodemask(gfp_mask, order, zonelist, NULL);
301 }
302 
303 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
304 						unsigned int order)
305 {
306 	/* Unknown node is current node */
307 	if (nid < 0)
308 		nid = numa_node_id();
309 
310 	return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
311 }
312 
313 static inline struct page *alloc_pages_exact_node(int nid, gfp_t gfp_mask,
314 						unsigned int order)
315 {
316 	VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES || !node_online(nid));
317 
318 	return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
319 }
320 
321 #ifdef CONFIG_NUMA
322 extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
323 
324 static inline struct page *
325 alloc_pages(gfp_t gfp_mask, unsigned int order)
326 {
327 	return alloc_pages_current(gfp_mask, order);
328 }
329 extern struct page *alloc_pages_vma(gfp_t gfp_mask, int order,
330 			struct vm_area_struct *vma, unsigned long addr,
331 			int node, bool hugepage);
332 #define alloc_hugepage_vma(gfp_mask, vma, addr, order)	\
333 	alloc_pages_vma(gfp_mask, order, vma, addr, numa_node_id(), true)
334 #else
335 #define alloc_pages(gfp_mask, order) \
336 		alloc_pages_node(numa_node_id(), gfp_mask, order)
337 #define alloc_pages_vma(gfp_mask, order, vma, addr, node, false)\
338 	alloc_pages(gfp_mask, order)
339 #define alloc_hugepage_vma(gfp_mask, vma, addr, order)	\
340 	alloc_pages(gfp_mask, order)
341 #endif
342 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
343 #define alloc_page_vma(gfp_mask, vma, addr)			\
344 	alloc_pages_vma(gfp_mask, 0, vma, addr, numa_node_id(), false)
345 #define alloc_page_vma_node(gfp_mask, vma, addr, node)		\
346 	alloc_pages_vma(gfp_mask, 0, vma, addr, node, false)
347 
348 extern struct page *alloc_kmem_pages(gfp_t gfp_mask, unsigned int order);
349 extern struct page *alloc_kmem_pages_node(int nid, gfp_t gfp_mask,
350 					  unsigned int order);
351 
352 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
353 extern unsigned long get_zeroed_page(gfp_t gfp_mask);
354 
355 void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
356 void free_pages_exact(void *virt, size_t size);
357 /* This is different from alloc_pages_exact_node !!! */
358 void * __meminit alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask);
359 
360 #define __get_free_page(gfp_mask) \
361 		__get_free_pages((gfp_mask), 0)
362 
363 #define __get_dma_pages(gfp_mask, order) \
364 		__get_free_pages((gfp_mask) | GFP_DMA, (order))
365 
366 extern void __free_pages(struct page *page, unsigned int order);
367 extern void free_pages(unsigned long addr, unsigned int order);
368 extern void free_hot_cold_page(struct page *page, bool cold);
369 extern void free_hot_cold_page_list(struct list_head *list, bool cold);
370 
371 struct page_frag_cache;
372 extern void *__alloc_page_frag(struct page_frag_cache *nc,
373 			       unsigned int fragsz, gfp_t gfp_mask);
374 extern void __free_page_frag(void *addr);
375 
376 extern void __free_kmem_pages(struct page *page, unsigned int order);
377 extern void free_kmem_pages(unsigned long addr, unsigned int order);
378 
379 #define __free_page(page) __free_pages((page), 0)
380 #define free_page(addr) free_pages((addr), 0)
381 
382 void page_alloc_init(void);
383 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
384 void drain_all_pages(struct zone *zone);
385 void drain_local_pages(struct zone *zone);
386 
387 #ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
388 void page_alloc_init_late(void);
389 #else
390 static inline void page_alloc_init_late(void)
391 {
392 }
393 #endif
394 
395 /*
396  * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
397  * GFP flags are used before interrupts are enabled. Once interrupts are
398  * enabled, it is set to __GFP_BITS_MASK while the system is running. During
399  * hibernation, it is used by PM to avoid I/O during memory allocation while
400  * devices are suspended.
401  */
402 extern gfp_t gfp_allowed_mask;
403 
404 /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
405 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
406 
407 extern void pm_restrict_gfp_mask(void);
408 extern void pm_restore_gfp_mask(void);
409 
410 #ifdef CONFIG_PM_SLEEP
411 extern bool pm_suspended_storage(void);
412 #else
413 static inline bool pm_suspended_storage(void)
414 {
415 	return false;
416 }
417 #endif /* CONFIG_PM_SLEEP */
418 
419 #ifdef CONFIG_CMA
420 
421 /* The below functions must be run on a range from a single zone. */
422 extern int alloc_contig_range(unsigned long start, unsigned long end,
423 			      unsigned migratetype);
424 extern void free_contig_range(unsigned long pfn, unsigned nr_pages);
425 
426 /* CMA stuff */
427 extern void init_cma_reserved_pageblock(struct page *page);
428 
429 #endif
430 
431 #endif /* __LINUX_GFP_H */
432