Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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
8struct vm_area_struct;
9
10/*
11 * GFP bitmasks..
12 *
13 * Zone modifiers (see linux/mmzone.h - low three bits)
14 *
15 * Do not put any conditional on these. If necessary modify the definitions
16 * without the underscores and use the consistently. The definitions here may
17 * be used in bit comparisons.
18 */
19#define __GFP_DMA ((__force gfp_t)0x01u)
20#define __GFP_HIGHMEM ((__force gfp_t)0x02u)
21#define __GFP_DMA32 ((__force gfp_t)0x04u)
22
23/*
24 * Action modifiers - doesn't change the zoning
25 *
26 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
27 * _might_ fail. This depends upon the particular VM implementation.
28 *
29 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
30 * cannot handle allocation failures.
31 *
32 * __GFP_NORETRY: The VM implementation must not retry indefinitely.
33 *
34 * __GFP_MOVABLE: Flag that this page will be movable by the page migration
35 * mechanism or reclaimed
36 */
37#define __GFP_WAIT ((__force gfp_t)0x10u) /* Can wait and reschedule? */
38#define __GFP_HIGH ((__force gfp_t)0x20u) /* Should access emergency pools? */
39#define __GFP_IO ((__force gfp_t)0x40u) /* Can start physical IO? */
40#define __GFP_FS ((__force gfp_t)0x80u) /* Can call down to low-level FS? */
41#define __GFP_COLD ((__force gfp_t)0x100u) /* Cache-cold page required */
42#define __GFP_NOWARN ((__force gfp_t)0x200u) /* Suppress page allocation failure warning */
43#define __GFP_REPEAT ((__force gfp_t)0x400u) /* See above */
44#define __GFP_NOFAIL ((__force gfp_t)0x800u) /* See above */
45#define __GFP_NORETRY ((__force gfp_t)0x1000u)/* See above */
46#define __GFP_COMP ((__force gfp_t)0x4000u)/* Add compound page metadata */
47#define __GFP_ZERO ((__force gfp_t)0x8000u)/* Return zeroed page on success */
48#define __GFP_NOMEMALLOC ((__force gfp_t)0x10000u) /* Don't use emergency reserves */
49#define __GFP_HARDWALL ((__force gfp_t)0x20000u) /* Enforce hardwall cpuset memory allocs */
50#define __GFP_THISNODE ((__force gfp_t)0x40000u)/* No fallback, no policies */
51#define __GFP_RECLAIMABLE ((__force gfp_t)0x80000u) /* Page is reclaimable */
52#define __GFP_MOVABLE ((__force gfp_t)0x100000u) /* Page is movable */
53
54#define __GFP_BITS_SHIFT 21 /* Room for 21 __GFP_FOO bits */
55#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
56
57/* This equals 0, but use constants in case they ever change */
58#define GFP_NOWAIT (GFP_ATOMIC & ~__GFP_HIGH)
59/* GFP_ATOMIC means both !wait (__GFP_WAIT not set) and use emergency pool */
60#define GFP_ATOMIC (__GFP_HIGH)
61#define GFP_NOIO (__GFP_WAIT)
62#define GFP_NOFS (__GFP_WAIT | __GFP_IO)
63#define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS)
64#define GFP_TEMPORARY (__GFP_WAIT | __GFP_IO | __GFP_FS | \
65 __GFP_RECLAIMABLE)
66#define GFP_USER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
67#define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL | \
68 __GFP_HIGHMEM)
69#define GFP_HIGHUSER_MOVABLE (__GFP_WAIT | __GFP_IO | __GFP_FS | \
70 __GFP_HARDWALL | __GFP_HIGHMEM | \
71 __GFP_MOVABLE)
72
73#ifdef CONFIG_NUMA
74#define GFP_THISNODE (__GFP_THISNODE | __GFP_NOWARN | __GFP_NORETRY)
75#else
76#define GFP_THISNODE ((__force gfp_t)0)
77#endif
78
79/* This mask makes up all the page movable related flags */
80#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE)
81
82/* Control page allocator reclaim behavior */
83#define GFP_RECLAIM_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS|\
84 __GFP_NOWARN|__GFP_REPEAT|__GFP_NOFAIL|\
85 __GFP_NORETRY|__GFP_NOMEMALLOC)
86
87/* Control allocation constraints */
88#define GFP_CONSTRAINT_MASK (__GFP_HARDWALL|__GFP_THISNODE)
89
90/* Do not use these with a slab allocator */
91#define GFP_SLAB_BUG_MASK (__GFP_DMA32|__GFP_HIGHMEM|~__GFP_BITS_MASK)
92
93/* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
94 platforms, used as appropriate on others */
95
96#define GFP_DMA __GFP_DMA
97
98/* 4GB DMA on some platforms */
99#define GFP_DMA32 __GFP_DMA32
100
101/* Convert GFP flags to their corresponding migrate type */
102static inline int allocflags_to_migratetype(gfp_t gfp_flags)
103{
104 WARN_ON((gfp_flags & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK);
105
106 if (unlikely(page_group_by_mobility_disabled))
107 return MIGRATE_UNMOVABLE;
108
109 /* Group based on mobility */
110 return (((gfp_flags & __GFP_MOVABLE) != 0) << 1) |
111 ((gfp_flags & __GFP_RECLAIMABLE) != 0);
112}
113
114static inline enum zone_type gfp_zone(gfp_t flags)
115{
116#ifdef CONFIG_ZONE_DMA
117 if (flags & __GFP_DMA)
118 return ZONE_DMA;
119#endif
120#ifdef CONFIG_ZONE_DMA32
121 if (flags & __GFP_DMA32)
122 return ZONE_DMA32;
123#endif
124 if ((flags & (__GFP_HIGHMEM | __GFP_MOVABLE)) ==
125 (__GFP_HIGHMEM | __GFP_MOVABLE))
126 return ZONE_MOVABLE;
127#ifdef CONFIG_HIGHMEM
128 if (flags & __GFP_HIGHMEM)
129 return ZONE_HIGHMEM;
130#endif
131 return ZONE_NORMAL;
132}
133
134/*
135 * There is only one page-allocator function, and two main namespaces to
136 * it. The alloc_page*() variants return 'struct page *' and as such
137 * can allocate highmem pages, the *get*page*() variants return
138 * virtual kernel addresses to the allocated page(s).
139 */
140
141static inline int gfp_zonelist(gfp_t flags)
142{
143 if (NUMA_BUILD && unlikely(flags & __GFP_THISNODE))
144 return 1;
145
146 return 0;
147}
148
149/*
150 * We get the zone list from the current node and the gfp_mask.
151 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
152 * There are two zonelists per node, one for all zones with memory and
153 * one containing just zones from the node the zonelist belongs to.
154 *
155 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
156 * optimized to &contig_page_data at compile-time.
157 */
158static inline struct zonelist *node_zonelist(int nid, gfp_t flags)
159{
160 return NODE_DATA(nid)->node_zonelists + gfp_zonelist(flags);
161}
162
163#ifndef HAVE_ARCH_FREE_PAGE
164static inline void arch_free_page(struct page *page, int order) { }
165#endif
166#ifndef HAVE_ARCH_ALLOC_PAGE
167static inline void arch_alloc_page(struct page *page, int order) { }
168#endif
169
170struct page *
171__alloc_pages_internal(gfp_t gfp_mask, unsigned int order,
172 struct zonelist *zonelist, nodemask_t *nodemask);
173
174static inline struct page *
175__alloc_pages(gfp_t gfp_mask, unsigned int order,
176 struct zonelist *zonelist)
177{
178 return __alloc_pages_internal(gfp_mask, order, zonelist, NULL);
179}
180
181static inline struct page *
182__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
183 struct zonelist *zonelist, nodemask_t *nodemask)
184{
185 return __alloc_pages_internal(gfp_mask, order, zonelist, nodemask);
186}
187
188
189static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
190 unsigned int order)
191{
192 if (unlikely(order >= MAX_ORDER))
193 return NULL;
194
195 /* Unknown node is current node */
196 if (nid < 0)
197 nid = numa_node_id();
198
199 return __alloc_pages(gfp_mask, order, node_zonelist(nid, gfp_mask));
200}
201
202#ifdef CONFIG_NUMA
203extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
204
205static inline struct page *
206alloc_pages(gfp_t gfp_mask, unsigned int order)
207{
208 if (unlikely(order >= MAX_ORDER))
209 return NULL;
210
211 return alloc_pages_current(gfp_mask, order);
212}
213extern struct page *alloc_page_vma(gfp_t gfp_mask,
214 struct vm_area_struct *vma, unsigned long addr);
215#else
216#define alloc_pages(gfp_mask, order) \
217 alloc_pages_node(numa_node_id(), gfp_mask, order)
218#define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0)
219#endif
220#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
221
222extern unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order);
223extern unsigned long get_zeroed_page(gfp_t gfp_mask);
224
225void *alloc_pages_exact(size_t size, gfp_t gfp_mask);
226void free_pages_exact(void *virt, size_t size);
227
228#define __get_free_page(gfp_mask) \
229 __get_free_pages((gfp_mask),0)
230
231#define __get_dma_pages(gfp_mask, order) \
232 __get_free_pages((gfp_mask) | GFP_DMA,(order))
233
234extern void __free_pages(struct page *page, unsigned int order);
235extern void free_pages(unsigned long addr, unsigned int order);
236extern void free_hot_page(struct page *page);
237extern void free_cold_page(struct page *page);
238
239#define __free_page(page) __free_pages((page), 0)
240#define free_page(addr) free_pages((addr),0)
241
242void page_alloc_init(void);
243void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp);
244void drain_all_pages(void);
245void drain_local_pages(void *dummy);
246
247#endif /* __LINUX_GFP_H */