Linux kernel mirror (for testing)
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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 in GFP_ZONEMASK (see linux/mmzone.h - low three bits) */
14#define __GFP_DMA ((__force gfp_t)0x01u)
15#define __GFP_HIGHMEM ((__force gfp_t)0x02u)
16#ifdef CONFIG_DMA_IS_DMA32
17#define __GFP_DMA32 ((__force gfp_t)0x01) /* ZONE_DMA is ZONE_DMA32 */
18#elif BITS_PER_LONG < 64
19#define __GFP_DMA32 ((__force gfp_t)0x00) /* ZONE_NORMAL is ZONE_DMA32 */
20#else
21#define __GFP_DMA32 ((__force gfp_t)0x04) /* Has own ZONE_DMA32 */
22#endif
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#define __GFP_WAIT ((__force gfp_t)0x10u) /* Can wait and reschedule? */
36#define __GFP_HIGH ((__force gfp_t)0x20u) /* Should access emergency pools? */
37#define __GFP_IO ((__force gfp_t)0x40u) /* Can start physical IO? */
38#define __GFP_FS ((__force gfp_t)0x80u) /* Can call down to low-level FS? */
39#define __GFP_COLD ((__force gfp_t)0x100u) /* Cache-cold page required */
40#define __GFP_NOWARN ((__force gfp_t)0x200u) /* Suppress page allocation failure warning */
41#define __GFP_REPEAT ((__force gfp_t)0x400u) /* Retry the allocation. Might fail */
42#define __GFP_NOFAIL ((__force gfp_t)0x800u) /* Retry for ever. Cannot fail */
43#define __GFP_NORETRY ((__force gfp_t)0x1000u)/* Do not retry. Might fail */
44#define __GFP_NO_GROW ((__force gfp_t)0x2000u)/* Slab internal usage */
45#define __GFP_COMP ((__force gfp_t)0x4000u)/* Add compound page metadata */
46#define __GFP_ZERO ((__force gfp_t)0x8000u)/* Return zeroed page on success */
47#define __GFP_NOMEMALLOC ((__force gfp_t)0x10000u) /* Don't use emergency reserves */
48#define __GFP_HARDWALL ((__force gfp_t)0x20000u) /* Enforce hardwall cpuset memory allocs */
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)
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/* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
71 platforms, used as appropriate on others */
72
73#define GFP_DMA __GFP_DMA
74
75/* 4GB DMA on some platforms */
76#define GFP_DMA32 __GFP_DMA32
77
78
79static inline int gfp_zone(gfp_t gfp)
80{
81 int zone = GFP_ZONEMASK & (__force int) gfp;
82 BUG_ON(zone >= GFP_ZONETYPES);
83 return zone;
84}
85
86/*
87 * There is only one page-allocator function, and two main namespaces to
88 * it. The alloc_page*() variants return 'struct page *' and as such
89 * can allocate highmem pages, the *get*page*() variants return
90 * virtual kernel addresses to the allocated page(s).
91 */
92
93/*
94 * We get the zone list from the current node and the gfp_mask.
95 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
96 *
97 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
98 * optimized to &contig_page_data at compile-time.
99 */
100
101#ifndef HAVE_ARCH_FREE_PAGE
102static inline void arch_free_page(struct page *page, int order) { }
103#endif
104
105extern struct page *
106FASTCALL(__alloc_pages(gfp_t, unsigned int, struct zonelist *));
107
108static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
109 unsigned int order)
110{
111 if (unlikely(order >= MAX_ORDER))
112 return NULL;
113
114 /* Unknown node is current node */
115 if (nid < 0)
116 nid = numa_node_id();
117
118 return __alloc_pages(gfp_mask, order,
119 NODE_DATA(nid)->node_zonelists + gfp_zone(gfp_mask));
120}
121
122#ifdef CONFIG_NUMA
123extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
124
125static inline struct page *
126alloc_pages(gfp_t gfp_mask, unsigned int order)
127{
128 if (unlikely(order >= MAX_ORDER))
129 return NULL;
130
131 return alloc_pages_current(gfp_mask, order);
132}
133extern struct page *alloc_page_vma(gfp_t gfp_mask,
134 struct vm_area_struct *vma, unsigned long addr);
135#else
136#define alloc_pages(gfp_mask, order) \
137 alloc_pages_node(numa_node_id(), gfp_mask, order)
138#define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0)
139#endif
140#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
141
142extern unsigned long FASTCALL(__get_free_pages(gfp_t gfp_mask, unsigned int order));
143extern unsigned long FASTCALL(get_zeroed_page(gfp_t gfp_mask));
144
145#define __get_free_page(gfp_mask) \
146 __get_free_pages((gfp_mask),0)
147
148#define __get_dma_pages(gfp_mask, order) \
149 __get_free_pages((gfp_mask) | GFP_DMA,(order))
150
151extern void FASTCALL(__free_pages(struct page *page, unsigned int order));
152extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));
153extern void FASTCALL(free_hot_page(struct page *page));
154extern void FASTCALL(free_cold_page(struct page *page));
155
156#define __free_page(page) __free_pages((page), 0)
157#define free_page(addr) free_pages((addr),0)
158
159void page_alloc_init(void);
160#ifdef CONFIG_NUMA
161void drain_node_pages(int node);
162#else
163static inline void drain_node_pages(int node) { };
164#endif
165
166#endif /* __LINUX_GFP_H */