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