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#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 three bits) */
15#define __GFP_DMA ((__force gfp_t)0x01u)
16#define __GFP_HIGHMEM ((__force gfp_t)0x02u)
17#ifdef CONFIG_DMA_IS_DMA32
18#define __GFP_DMA32 ((__force gfp_t)0x01) /* ZONE_DMA is ZONE_DMA32 */
19#elif BITS_PER_LONG < 64
20#define __GFP_DMA32 ((__force gfp_t)0x00) /* ZONE_NORMAL is ZONE_DMA32 */
21#else
22#define __GFP_DMA32 ((__force gfp_t)0x04) /* Has own ZONE_DMA32 */
23#endif
24
25/*
26 * Action modifiers - doesn't change the zoning
27 *
28 * __GFP_REPEAT: Try hard to allocate the memory, but the allocation attempt
29 * _might_ fail. This depends upon the particular VM implementation.
30 *
31 * __GFP_NOFAIL: The VM implementation _must_ retry infinitely: the caller
32 * cannot handle allocation failures.
33 *
34 * __GFP_NORETRY: The VM implementation must not retry indefinitely.
35 */
36#define __GFP_WAIT ((__force gfp_t)0x10u) /* Can wait and reschedule? */
37#define __GFP_HIGH ((__force gfp_t)0x20u) /* Should access emergency pools? */
38#define __GFP_IO ((__force gfp_t)0x40u) /* Can start physical IO? */
39#define __GFP_FS ((__force gfp_t)0x80u) /* Can call down to low-level FS? */
40#define __GFP_COLD ((__force gfp_t)0x100u) /* Cache-cold page required */
41#define __GFP_NOWARN ((__force gfp_t)0x200u) /* Suppress page allocation failure warning */
42#define __GFP_REPEAT ((__force gfp_t)0x400u) /* Retry the allocation. Might fail */
43#define __GFP_NOFAIL ((__force gfp_t)0x800u) /* Retry for ever. Cannot fail */
44#define __GFP_NORETRY ((__force gfp_t)0x1000u)/* Do not retry. Might fail */
45#define __GFP_NO_GROW ((__force gfp_t)0x2000u)/* Slab internal usage */
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
51#define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */
52#define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1))
53
54/* if you forget to add the bitmask here kernel will crash, period */
55#define GFP_LEVEL_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS| \
56 __GFP_COLD|__GFP_NOWARN|__GFP_REPEAT| \
57 __GFP_NOFAIL|__GFP_NORETRY|__GFP_NO_GROW|__GFP_COMP| \
58 __GFP_NOMEMALLOC|__GFP_HARDWALL)
59
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_USER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL)
66#define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL | \
67 __GFP_HIGHMEM)
68
69/* Flag - indicates that the buffer will be suitable for DMA. Ignored on some
70 platforms, used as appropriate on others */
71
72#define GFP_DMA __GFP_DMA
73
74/* 4GB DMA on some platforms */
75#define GFP_DMA32 __GFP_DMA32
76
77
78static inline int gfp_zone(gfp_t gfp)
79{
80 int zone = GFP_ZONEMASK & (__force int) gfp;
81 BUG_ON(zone >= GFP_ZONETYPES);
82 return zone;
83}
84
85/*
86 * There is only one page-allocator function, and two main namespaces to
87 * it. The alloc_page*() variants return 'struct page *' and as such
88 * can allocate highmem pages, the *get*page*() variants return
89 * virtual kernel addresses to the allocated page(s).
90 */
91
92/*
93 * We get the zone list from the current node and the gfp_mask.
94 * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
95 *
96 * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
97 * optimized to &contig_page_data at compile-time.
98 */
99
100#ifndef HAVE_ARCH_FREE_PAGE
101static inline void arch_free_page(struct page *page, int order) { }
102#endif
103
104extern struct page *
105FASTCALL(__alloc_pages(gfp_t, unsigned int, struct zonelist *));
106
107static inline struct page *alloc_pages_node(int nid, gfp_t gfp_mask,
108 unsigned int order)
109{
110 if (unlikely(order >= MAX_ORDER))
111 return NULL;
112
113 /* Unknown node is current node */
114 if (nid < 0)
115 nid = numa_node_id();
116
117 return __alloc_pages(gfp_mask, order,
118 NODE_DATA(nid)->node_zonelists + gfp_zone(gfp_mask));
119}
120
121#ifdef CONFIG_NUMA
122extern struct page *alloc_pages_current(gfp_t gfp_mask, unsigned order);
123
124static inline struct page *
125alloc_pages(gfp_t gfp_mask, unsigned int order)
126{
127 if (unlikely(order >= MAX_ORDER))
128 return NULL;
129
130 return alloc_pages_current(gfp_mask, order);
131}
132extern struct page *alloc_page_vma(gfp_t gfp_mask,
133 struct vm_area_struct *vma, unsigned long addr);
134#else
135#define alloc_pages(gfp_mask, order) \
136 alloc_pages_node(numa_node_id(), gfp_mask, order)
137#define alloc_page_vma(gfp_mask, vma, addr) alloc_pages(gfp_mask, 0)
138#endif
139#define alloc_page(gfp_mask) alloc_pages(gfp_mask, 0)
140
141extern unsigned long FASTCALL(__get_free_pages(gfp_t gfp_mask, unsigned int order));
142extern unsigned long FASTCALL(get_zeroed_page(gfp_t gfp_mask));
143
144#define __get_free_page(gfp_mask) \
145 __get_free_pages((gfp_mask),0)
146
147#define __get_dma_pages(gfp_mask, order) \
148 __get_free_pages((gfp_mask) | GFP_DMA,(order))
149
150extern void FASTCALL(__free_pages(struct page *page, unsigned int order));
151extern void FASTCALL(free_pages(unsigned long addr, unsigned int order));
152extern void FASTCALL(free_hot_page(struct page *page));
153extern void FASTCALL(free_cold_page(struct page *page));
154
155#define __free_page(page) __free_pages((page), 0)
156#define free_page(addr) free_pages((addr),0)
157
158void page_alloc_init(void);
159#ifdef CONFIG_NUMA
160void drain_node_pages(int node);
161#else
162static inline void drain_node_pages(int node) { };
163#endif
164
165#endif /* __LINUX_GFP_H */