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