xref: /openbmc/linux/include/linux/gfp.h (revision 27cd25e3)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_GFP_H
3 #define __LINUX_GFP_H
4 
5 #include <linux/gfp_types.h>
6 
7 #include <linux/mmzone.h>
8 #include <linux/topology.h>
9 
10 struct vm_area_struct;
11 
12 /* Convert GFP flags to their corresponding migrate type */
13 #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
14 #define GFP_MOVABLE_SHIFT 3
15 
gfp_migratetype(const gfp_t gfp_flags)16 static inline int gfp_migratetype(const gfp_t gfp_flags)
17 {
18 	VM_WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
19 	BUILD_BUG_ON((1UL << GFP_MOVABLE_SHIFT) != ___GFP_MOVABLE);
20 	BUILD_BUG_ON((___GFP_MOVABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_MOVABLE);
21 	BUILD_BUG_ON((___GFP_RECLAIMABLE >> GFP_MOVABLE_SHIFT) != MIGRATE_RECLAIMABLE);
22 	BUILD_BUG_ON(((___GFP_MOVABLE | ___GFP_RECLAIMABLE) >>
23 		      GFP_MOVABLE_SHIFT) != MIGRATE_HIGHATOMIC);
24 
25 	if (unlikely(page_group_by_mobility_disabled))
26 		return MIGRATE_UNMOVABLE;
27 
28 	/* Group based on mobility */
29 	return (__force unsigned long)(gfp_flags & GFP_MOVABLE_MASK) >> GFP_MOVABLE_SHIFT;
30 }
31 #undef GFP_MOVABLE_MASK
32 #undef GFP_MOVABLE_SHIFT
33 
gfpflags_allow_blocking(const gfp_t gfp_flags)34 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
35 {
36 	return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
37 }
38 
39 #ifdef CONFIG_HIGHMEM
40 #define OPT_ZONE_HIGHMEM ZONE_HIGHMEM
41 #else
42 #define OPT_ZONE_HIGHMEM ZONE_NORMAL
43 #endif
44 
45 #ifdef CONFIG_ZONE_DMA
46 #define OPT_ZONE_DMA ZONE_DMA
47 #else
48 #define OPT_ZONE_DMA ZONE_NORMAL
49 #endif
50 
51 #ifdef CONFIG_ZONE_DMA32
52 #define OPT_ZONE_DMA32 ZONE_DMA32
53 #else
54 #define OPT_ZONE_DMA32 ZONE_NORMAL
55 #endif
56 
57 /*
58  * GFP_ZONE_TABLE is a word size bitstring that is used for looking up the
59  * zone to use given the lowest 4 bits of gfp_t. Entries are GFP_ZONES_SHIFT
60  * bits long and there are 16 of them to cover all possible combinations of
61  * __GFP_DMA, __GFP_DMA32, __GFP_MOVABLE and __GFP_HIGHMEM.
62  *
63  * The zone fallback order is MOVABLE=>HIGHMEM=>NORMAL=>DMA32=>DMA.
64  * But GFP_MOVABLE is not only a zone specifier but also an allocation
65  * policy. Therefore __GFP_MOVABLE plus another zone selector is valid.
66  * Only 1 bit of the lowest 3 bits (DMA,DMA32,HIGHMEM) can be set to "1".
67  *
68  *       bit       result
69  *       =================
70  *       0x0    => NORMAL
71  *       0x1    => DMA or NORMAL
72  *       0x2    => HIGHMEM or NORMAL
73  *       0x3    => BAD (DMA+HIGHMEM)
74  *       0x4    => DMA32 or NORMAL
75  *       0x5    => BAD (DMA+DMA32)
76  *       0x6    => BAD (HIGHMEM+DMA32)
77  *       0x7    => BAD (HIGHMEM+DMA32+DMA)
78  *       0x8    => NORMAL (MOVABLE+0)
79  *       0x9    => DMA or NORMAL (MOVABLE+DMA)
80  *       0xa    => MOVABLE (Movable is valid only if HIGHMEM is set too)
81  *       0xb    => BAD (MOVABLE+HIGHMEM+DMA)
82  *       0xc    => DMA32 or NORMAL (MOVABLE+DMA32)
83  *       0xd    => BAD (MOVABLE+DMA32+DMA)
84  *       0xe    => BAD (MOVABLE+DMA32+HIGHMEM)
85  *       0xf    => BAD (MOVABLE+DMA32+HIGHMEM+DMA)
86  *
87  * GFP_ZONES_SHIFT must be <= 2 on 32 bit platforms.
88  */
89 
90 #if defined(CONFIG_ZONE_DEVICE) && (MAX_NR_ZONES-1) <= 4
91 /* ZONE_DEVICE is not a valid GFP zone specifier */
92 #define GFP_ZONES_SHIFT 2
93 #else
94 #define GFP_ZONES_SHIFT ZONES_SHIFT
95 #endif
96 
97 #if 16 * GFP_ZONES_SHIFT > BITS_PER_LONG
98 #error GFP_ZONES_SHIFT too large to create GFP_ZONE_TABLE integer
99 #endif
100 
101 #define GFP_ZONE_TABLE ( \
102 	(ZONE_NORMAL << 0 * GFP_ZONES_SHIFT)				       \
103 	| (OPT_ZONE_DMA << ___GFP_DMA * GFP_ZONES_SHIFT)		       \
104 	| (OPT_ZONE_HIGHMEM << ___GFP_HIGHMEM * GFP_ZONES_SHIFT)	       \
105 	| (OPT_ZONE_DMA32 << ___GFP_DMA32 * GFP_ZONES_SHIFT)		       \
106 	| (ZONE_NORMAL << ___GFP_MOVABLE * GFP_ZONES_SHIFT)		       \
107 	| (OPT_ZONE_DMA << (___GFP_MOVABLE | ___GFP_DMA) * GFP_ZONES_SHIFT)    \
108 	| (ZONE_MOVABLE << (___GFP_MOVABLE | ___GFP_HIGHMEM) * GFP_ZONES_SHIFT)\
109 	| (OPT_ZONE_DMA32 << (___GFP_MOVABLE | ___GFP_DMA32) * GFP_ZONES_SHIFT)\
110 )
111 
112 /*
113  * GFP_ZONE_BAD is a bitmap for all combinations of __GFP_DMA, __GFP_DMA32
114  * __GFP_HIGHMEM and __GFP_MOVABLE that are not permitted. One flag per
115  * entry starting with bit 0. Bit is set if the combination is not
116  * allowed.
117  */
118 #define GFP_ZONE_BAD ( \
119 	1 << (___GFP_DMA | ___GFP_HIGHMEM)				      \
120 	| 1 << (___GFP_DMA | ___GFP_DMA32)				      \
121 	| 1 << (___GFP_DMA32 | ___GFP_HIGHMEM)				      \
122 	| 1 << (___GFP_DMA | ___GFP_DMA32 | ___GFP_HIGHMEM)		      \
123 	| 1 << (___GFP_MOVABLE | ___GFP_HIGHMEM | ___GFP_DMA)		      \
124 	| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA)		      \
125 	| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_HIGHMEM)		      \
126 	| 1 << (___GFP_MOVABLE | ___GFP_DMA32 | ___GFP_DMA | ___GFP_HIGHMEM)  \
127 )
128 
gfp_zone(gfp_t flags)129 static inline enum zone_type gfp_zone(gfp_t flags)
130 {
131 	enum zone_type z;
132 	int bit = (__force int) (flags & GFP_ZONEMASK);
133 
134 	z = (GFP_ZONE_TABLE >> (bit * GFP_ZONES_SHIFT)) &
135 					 ((1 << GFP_ZONES_SHIFT) - 1);
136 	VM_BUG_ON((GFP_ZONE_BAD >> bit) & 1);
137 	return z;
138 }
139 
140 /*
141  * There is only one page-allocator function, and two main namespaces to
142  * it. The alloc_page*() variants return 'struct page *' and as such
143  * can allocate highmem pages, the *get*page*() variants return
144  * virtual kernel addresses to the allocated page(s).
145  */
146 
gfp_zonelist(gfp_t flags)147 static inline int gfp_zonelist(gfp_t flags)
148 {
149 #ifdef CONFIG_NUMA
150 	if (unlikely(flags & __GFP_THISNODE))
151 		return ZONELIST_NOFALLBACK;
152 #endif
153 	return ZONELIST_FALLBACK;
154 }
155 
156 /*
157  * We get the zone list from the current node and the gfp_mask.
158  * This zone list contains a maximum of MAX_NUMNODES*MAX_NR_ZONES zones.
159  * There are two zonelists per node, one for all zones with memory and
160  * one containing just zones from the node the zonelist belongs to.
161  *
162  * For the case of non-NUMA systems the NODE_DATA() gets optimized to
163  * &contig_page_data at compile-time.
164  */
node_zonelist(int nid,gfp_t flags)165 static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
166 {
167 	return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
168 }
169 
170 #ifndef HAVE_ARCH_FREE_PAGE
arch_free_page(struct page * page,int order)171 static inline void arch_free_page(struct page *page, int order) { }
172 #endif
173 #ifndef HAVE_ARCH_ALLOC_PAGE
arch_alloc_page(struct page * page,int order)174 static inline void arch_alloc_page(struct page *page, int order) { }
175 #endif
176 
177 struct page *__alloc_pages(gfp_t gfp, unsigned int order, int preferred_nid,
178 		nodemask_t *nodemask);
179 struct folio *__folio_alloc(gfp_t gfp, unsigned int order, int preferred_nid,
180 		nodemask_t *nodemask);
181 
182 unsigned long __alloc_pages_bulk(gfp_t gfp, int preferred_nid,
183 				nodemask_t *nodemask, int nr_pages,
184 				struct list_head *page_list,
185 				struct page **page_array);
186 
187 unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp,
188 				unsigned long nr_pages,
189 				struct page **page_array);
190 
191 /* Bulk allocate order-0 pages */
192 static inline unsigned long
alloc_pages_bulk_list(gfp_t gfp,unsigned long nr_pages,struct list_head * list)193 alloc_pages_bulk_list(gfp_t gfp, unsigned long nr_pages, struct list_head *list)
194 {
195 	return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, list, NULL);
196 }
197 
198 static inline unsigned long
alloc_pages_bulk_array(gfp_t gfp,unsigned long nr_pages,struct page ** page_array)199 alloc_pages_bulk_array(gfp_t gfp, unsigned long nr_pages, struct page **page_array)
200 {
201 	return __alloc_pages_bulk(gfp, numa_mem_id(), NULL, nr_pages, NULL, page_array);
202 }
203 
204 static inline unsigned long
alloc_pages_bulk_array_node(gfp_t gfp,int nid,unsigned long nr_pages,struct page ** page_array)205 alloc_pages_bulk_array_node(gfp_t gfp, int nid, unsigned long nr_pages, struct page **page_array)
206 {
207 	if (nid == NUMA_NO_NODE)
208 		nid = numa_mem_id();
209 
210 	return __alloc_pages_bulk(gfp, nid, NULL, nr_pages, NULL, page_array);
211 }
212 
warn_if_node_offline(int this_node,gfp_t gfp_mask)213 static inline void warn_if_node_offline(int this_node, gfp_t gfp_mask)
214 {
215 	gfp_t warn_gfp = gfp_mask & (__GFP_THISNODE|__GFP_NOWARN);
216 
217 	if (warn_gfp != (__GFP_THISNODE|__GFP_NOWARN))
218 		return;
219 
220 	if (node_online(this_node))
221 		return;
222 
223 	pr_warn("%pGg allocation from offline node %d\n", &gfp_mask, this_node);
224 	dump_stack();
225 }
226 
227 /*
228  * Allocate pages, preferring the node given as nid. The node must be valid and
229  * online. For more general interface, see alloc_pages_node().
230  */
231 static inline struct page *
__alloc_pages_node(int nid,gfp_t gfp_mask,unsigned int order)232 __alloc_pages_node(int nid, gfp_t gfp_mask, unsigned int order)
233 {
234 	VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
235 	warn_if_node_offline(nid, gfp_mask);
236 
237 	return __alloc_pages(gfp_mask, order, nid, NULL);
238 }
239 
240 static inline
__folio_alloc_node(gfp_t gfp,unsigned int order,int nid)241 struct folio *__folio_alloc_node(gfp_t gfp, unsigned int order, int nid)
242 {
243 	VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES);
244 	warn_if_node_offline(nid, gfp);
245 
246 	return __folio_alloc(gfp, order, nid, NULL);
247 }
248 
249 /*
250  * Allocate pages, preferring the node given as nid. When nid == NUMA_NO_NODE,
251  * prefer the current CPU's closest node. Otherwise node must be valid and
252  * online.
253  */
alloc_pages_node(int nid,gfp_t gfp_mask,unsigned int order)254 static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
255 						unsigned int order)
256 {
257 	if (nid == NUMA_NO_NODE)
258 		nid = numa_mem_id();
259 
260 	return __alloc_pages_node(nid, gfp_mask, order);
261 }
262 
263 #ifdef CONFIG_NUMA
264 struct page *alloc_pages(gfp_t gfp, unsigned int order);
265 struct folio *folio_alloc(gfp_t gfp, unsigned order);
266 struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma,
267 		unsigned long addr, bool hugepage);
268 #else
alloc_pages(gfp_t gfp_mask,unsigned int order)269 static inline struct page *alloc_pages(gfp_t gfp_mask, unsigned int order)
270 {
271 	return alloc_pages_node(numa_node_id(), gfp_mask, order);
272 }
folio_alloc(gfp_t gfp,unsigned int order)273 static inline struct folio *folio_alloc(gfp_t gfp, unsigned int order)
274 {
275 	return __folio_alloc_node(gfp, order, numa_node_id());
276 }
277 #define vma_alloc_folio(gfp, order, vma, addr, hugepage)		\
278 	folio_alloc(gfp, order)
279 #endif
280 #define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
alloc_page_vma(gfp_t gfp,struct vm_area_struct * vma,unsigned long addr)281 static inline struct page *alloc_page_vma(gfp_t gfp,
282 		struct vm_area_struct *vma, unsigned long addr)
283 {
284 	struct folio *folio = vma_alloc_folio(gfp, 0, vma, addr, false);
285 
286 	return &folio->page;
287 }
288 
289 extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
290 extern unsigned long get_zeroed_page(gfp_t gfp_mask);
291 
292 void *alloc_pages_exact(size_t size, gfp_t gfp_mask) __alloc_size(1);
293 void free_pages_exact(void *virt, size_t size);
294 __meminit void *alloc_pages_exact_nid(int nid, size_t size, gfp_t gfp_mask) __alloc_size(2);
295 
296 #define __get_free_page(gfp_mask) \
297 		__get_free_pages((gfp_mask), 0)
298 
299 #define __get_dma_pages(gfp_mask, order) \
300 		__get_free_pages((gfp_mask) | GFP_DMA, (order))
301 
302 extern void __free_pages(struct page *page, unsigned int order);
303 extern void free_pages(unsigned long addr, unsigned int order);
304 
305 struct page_frag_cache;
306 extern void __page_frag_cache_drain(struct page *page, unsigned int count);
307 extern void *page_frag_alloc_align(struct page_frag_cache *nc,
308 				   unsigned int fragsz, gfp_t gfp_mask,
309 				   unsigned int align_mask);
310 
page_frag_alloc(struct page_frag_cache * nc,unsigned int fragsz,gfp_t gfp_mask)311 static inline void *page_frag_alloc(struct page_frag_cache *nc,
312 			     unsigned int fragsz, gfp_t gfp_mask)
313 {
314 	return page_frag_alloc_align(nc, fragsz, gfp_mask, ~0u);
315 }
316 
317 extern void page_frag_free(void *addr);
318 
319 #define __free_page(page) __free_pages((page), 0)
320 #define free_page(addr) free_pages((addr), 0)
321 
322 void page_alloc_init_cpuhp(void);
323 void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
324 void drain_all_pages(struct zone *zone);
325 void drain_local_pages(struct zone *zone);
326 
327 void page_alloc_init_late(void);
328 
329 /*
330  * gfp_allowed_mask is set to GFP_BOOT_MASK during early boot to restrict what
331  * GFP flags are used before interrupts are enabled. Once interrupts are
332  * enabled, it is set to __GFP_BITS_MASK while the system is running. During
333  * hibernation, it is used by PM to avoid I/O during memory allocation while
334  * devices are suspended.
335  */
336 extern gfp_t gfp_allowed_mask;
337 
338 /* Returns true if the gfp_mask allows use of ALLOC_NO_WATERMARK */
339 bool gfp_pfmemalloc_allowed(gfp_t gfp_mask);
340 
gfp_has_io_fs(gfp_t gfp)341 static inline bool gfp_has_io_fs(gfp_t gfp)
342 {
343 	return (gfp & (__GFP_IO | __GFP_FS)) == (__GFP_IO | __GFP_FS);
344 }
345 
346 /*
347  * Check if the gfp flags allow compaction - GFP_NOIO is a really
348  * tricky context because the migration might require IO.
349  */
gfp_compaction_allowed(gfp_t gfp_mask)350 static inline bool gfp_compaction_allowed(gfp_t gfp_mask)
351 {
352 	return IS_ENABLED(CONFIG_COMPACTION) && (gfp_mask & __GFP_IO);
353 }
354 
355 extern gfp_t vma_thp_gfp_mask(struct vm_area_struct *vma);
356 
357 #ifdef CONFIG_CONTIG_ALLOC
358 /* The below functions must be run on a range from a single zone. */
359 extern int alloc_contig_range(unsigned long start, unsigned long end,
360 			      unsigned migratetype, gfp_t gfp_mask);
361 extern struct page *alloc_contig_pages(unsigned long nr_pages, gfp_t gfp_mask,
362 				       int nid, nodemask_t *nodemask);
363 #endif
364 void free_contig_range(unsigned long pfn, unsigned long nr_pages);
365 
366 #endif /* __LINUX_GFP_H */
367