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#include <linux/config.h>
8
9struct vm_area_struct;
10
11/*
12 * GFP bitmasks..
13 */
14/* Zone modifiers in GFP_ZONEMASK (see linux/mmzone.h - low two bits) */
15#define __GFP_DMA 0x01u
16#define __GFP_HIGHMEM 0x02u
17
18/*
19 * Action modifiers - doesn't change the zoning
20 *
21 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
22 * _might_ fail. This depends upon the particular VM implementation.
23 *
24 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
25 * cannot handle allocation failures.
26 *
27 * __GFP_NORETRY: The VM implementation must not retry indefinitely.
28 */
29#define __GFP_WAIT 0x10u /* Can wait and reschedule? */
30#define __GFP_HIGH 0x20u /* Should access emergency pools? */
31#define __GFP_IO 0x40u /* Can start physical IO? */
32#define __GFP_FS 0x80u /* Can call down to low-level FS? */
33#define __GFP_COLD 0x100u /* Cache-cold page required */
34#define __GFP_NOWARN 0x200u /* Suppress page allocation failure warning */
35#define __GFP_REPEAT 0x400u /* Retry the allocation. Might fail */
36#define __GFP_NOFAIL 0x800u /* Retry for ever. Cannot fail */
37#define __GFP_NORETRY 0x1000u /* Do not retry. Might fail */
38#define __GFP_NO_GROW 0x2000u /* Slab internal usage */
39#define __GFP_COMP 0x4000u /* Add compound page metadata */
40#define __GFP_ZERO 0x8000u /* Return zeroed page on success */
41#define __GFP_NOMEMALLOC 0x10000u /* Don't use emergency reserves */
42#define __GFP_NORECLAIM 0x20000u /* No realy zone reclaim during allocation */
43
44#define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */
45#define __GFP_BITS_MASK ((1 << __GFP_BITS_SHIFT) - 1)
46
47/* if you forget to add the bitmask here kernel will crash, period */
48#define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \
49 __GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \
50 __GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP| \
51 __GFP_NOMEMALLOC|__GFP_NORECLAIM)
52
53#define GFP_ATOMIC (__GFP_HIGH)
54#define GFP_NOIO (__GFP_WAIT)
55#define GFP_NOFS (__GFP_WAIT | __GFP_IO)
56#define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS)
57#define GFP_USER (__GFP_WAIT | __GFP_IO | __GFP_FS)
58#define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HIGHMEM)
59
60/* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
61 platforms, used as appropriate on others */
62
63#define GFP_DMA __GFP_DMA
64
65
66/*
67 * There is only one page-allocator function, and two main namespaces to
68 * it. The alloc_page*() variants return 'struct page *' and as such
69 * can allocate highmem pages, the *get*page*() variants return
70 * virtual kernel addresses to the allocated page(s).
71 */
72
73/*
74 * We get the zone list from the current node and the gfp_mask.
75 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
76 *
77 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
78 * optimized to &contig_page_data at compile-time.
79 */
80
81#ifndef HAVE_ARCH_FREE_PAGE
82static inline void arch_free_page(struct page *page, int order) { }
83#endif
84
85extern struct page *
86FASTCALL(__alloc_pages(unsigned int, unsigned int, struct zonelist *));
87
88static inline struct page *alloc_pages_node(int nid, unsigned int __nocast gfp_mask,
89 unsigned int order)
90{
91 if (unlikely(order >= MAX_ORDER))
92 return NULL;
93
94 return __alloc_pages(gfp_mask, order,
95 NODE_DATA(nid)->node_zonelists + (gfp_mask & GFP_ZONEMASK));
96}
97
98#ifdef CONFIG_NUMA
99extern struct page *alloc_pages_current(unsigned int __nocast gfp_mask, unsigned order);
100
101static inline struct page *
102alloc_pages(unsigned int __nocast gfp_mask, unsigned int order)
103{
104 if (unlikely(order >= MAX_ORDER))
105 return NULL;
106
107 return alloc_pages_current(gfp_mask, order);
108}
109extern struct page *alloc_page_vma(unsigned __nocast gfp_mask,
110 struct vm_area_struct *vma, unsigned long addr);
111#else
112#define alloc_pages(gfp_mask, order) \
113 alloc_pages_node(numa_node_id(), gfp_mask, order)
114#define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0)
115#endif
116#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
117
118extern unsigned long FASTCALL(__get_free_pages(unsigned int __nocast gfp_mask, unsigned int order));
119extern unsigned long FASTCALL(get_zeroed_page(unsigned int __nocast gfp_mask));
120
121#define __get_free_page(gfp_mask) \
122 __get_free_pages((gfp_mask),0)
123
124#define __get_dma_pages(gfp_mask, order) \
125 __get_free_pages((gfp_mask) | GFP_DMA,(order))
126
127extern void FASTCALL(__free_pages(struct page *page, unsigned int order));
128extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));
129extern void FASTCALL(free_hot_page(struct page *page));
130extern void FASTCALL(free_cold_page(struct page *page));
131
132#define __free_page(page) __free_pages((page), 0)
133#define free_page(addr) free_pages((addr),0)
134
135void page_alloc_init(void);
136#ifdef CONFIG_NUMA
137void drain_remote_pages(void);
138#else
139static inline void drain_remote_pages(void) { };
140#endif
141
142#endif /* __LINUX_GFP_H */