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#define __GFP_WAIT ((__force gfp_t)0x10u) /* Can wait and reschedule? */
35#define __GFP_HIGH ((__force gfp_t)0x20u) /* Should access emergency pools? */
36#define __GFP_IO ((__force gfp_t)0x40u) /* Can start physical IO? */
37#define __GFP_FS ((__force gfp_t)0x80u) /* Can call down to low-level FS? */
38#define __GFP_COLD ((__force gfp_t)0x100u) /* Cache-cold page required */
39#define __GFP_NOWARN ((__force gfp_t)0x200u) /* Suppress page allocation failure warning */
40#define __GFP_REPEAT ((__force gfp_t)0x400u) /* Retry the allocation. Might fail */
41#define __GFP_NOFAIL ((__force gfp_t)0x800u) /* Retry for ever. Cannot fail */
42#define __GFP_NORETRY ((__force gfp_t)0x1000u)/* Do not retry. Might fail */
43#define __GFP_NO_GROW ((__force gfp_t)0x2000u)/* Slab internal usage */
44#define __GFP_COMP ((__force gfp_t)0x4000u)/* Add compound page metadata */
45#define __GFP_ZERO ((__force gfp_t)0x8000u)/* Return zeroed page on success */
46#define __GFP_NOMEMALLOC ((__force gfp_t)0x10000u) /* Don't use emergency reserves */
47#define __GFP_HARDWALL ((__force gfp_t)0x20000u) /* Enforce hardwall cpuset memory allocs */
48#define __GFP_THISNODE ((__force gfp_t)0x40000u)/* No fallback, no policies */
49
50#define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */
51#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
52
53/* if you forget to add the bitmask here kernel will crash, period */
54#define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \
55 __GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \
56 __GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP| \
57 __GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_THISNODE)
58
59/* This equals 0, but use constants in case they ever change */
60#define GFP_NOWAIT (GFP_ATOMIC & ~__GFP_HIGH)
61/* GFP_ATOMIC means both !wait (__GFP_WAIT not set) and use emergency pool */
62#define GFP_ATOMIC (__GFP_HIGH)
63#define GFP_NOIO (__GFP_WAIT)
64#define GFP_NOFS (__GFP_WAIT | __GFP_IO)
65#define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS)
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
70#ifdef CONFIG_NUMA
71#define GFP_THISNODE (__GFP_THISNODE | __GFP_NOWARN | __GFP_NORETRY)
72#else
73#define GFP_THISNODE ((__force gfp_t)0)
74#endif
75
76
77/* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
78 platforms, used as appropriate on others */
79
80#define GFP_DMA __GFP_DMA
81
82/* 4GB DMA on some platforms */
83#define GFP_DMA32 __GFP_DMA32
84
85
86static inline enum zone_type gfp_zone(gfp_t flags)
87{
88#ifdef CONFIG_ZONE_DMA
89 if (flags & __GFP_DMA)
90 return ZONE_DMA;
91#endif
92#ifdef CONFIG_ZONE_DMA32
93 if (flags & __GFP_DMA32)
94 return ZONE_DMA32;
95#endif
96#ifdef CONFIG_HIGHMEM
97 if (flags & __GFP_HIGHMEM)
98 return ZONE_HIGHMEM;
99#endif
100 return ZONE_NORMAL;
101}
102
103/*
104 * There is only one page-allocator function, and two main namespaces to
105 * it. The alloc_page*() variants return 'struct page *' and as such
106 * can allocate highmem pages, the *get*page*() variants return
107 * virtual kernel addresses to the allocated page(s).
108 */
109
110/*
111 * We get the zone list from the current node and the gfp_mask.
112 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
113 *
114 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
115 * optimized to &contig_page_data at compile-time.
116 */
117
118#ifndef HAVE_ARCH_FREE_PAGE
119static inline void arch_free_page(struct page *page, int order) { }
120#endif
121#ifndef HAVE_ARCH_ALLOC_PAGE
122static inline void arch_alloc_page(struct page *page, int order) { }
123#endif
124
125extern struct page *
126FASTCALL(__alloc_pages(gfp_t, unsigned int, struct zonelist *));
127
128static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
129 unsigned int order)
130{
131 if (unlikely(order >= MAX_ORDER))
132 return NULL;
133
134 /* Unknown node is current node */
135 if (nid < 0)
136 nid = numa_node_id();
137
138 return __alloc_pages(gfp_mask, order,
139 NODE_DATA(nid)->node_zonelists + gfp_zone(gfp_mask));
140}
141
142#ifdef CONFIG_NUMA
143extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
144
145static inline struct page *
146alloc_pages(gfp_t gfp_mask, unsigned int order)
147{
148 if (unlikely(order >= MAX_ORDER))
149 return NULL;
150
151 return alloc_pages_current(gfp_mask, order);
152}
153extern struct page *alloc_page_vma(gfp_t gfp_mask,
154 struct vm_area_struct *vma, unsigned long addr);
155#else
156#define alloc_pages(gfp_mask, order) \
157 alloc_pages_node(numa_node_id(), gfp_mask, order)
158#define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0)
159#endif
160#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
161
162extern unsigned long FASTCALL(__get_free_pages(gfp_t gfp_mask, unsigned int order));
163extern unsigned long FASTCALL(get_zeroed_page(gfp_t gfp_mask));
164
165#define __get_free_page(gfp_mask) \
166 __get_free_pages((gfp_mask),0)
167
168#define __get_dma_pages(gfp_mask, order) \
169 __get_free_pages((gfp_mask) | GFP_DMA,(order))
170
171extern void FASTCALL(__free_pages(struct page *page, unsigned int order));
172extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));
173extern void FASTCALL(free_hot_page(struct page *page));
174extern void FASTCALL(free_cold_page(struct page *page));
175
176#define __free_page(page) __free_pages((page), 0)
177#define free_page(addr) free_pages((addr),0)
178
179void page_alloc_init(void);
180#ifdef CONFIG_NUMA
181void drain_node_pages(int node);
182#else
183static inline void drain_node_pages(int node) { };
184#endif
185
186#endif /* __LINUX_GFP_H */